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19 pages, 483 KiB  
Article
Night Sleep, Parental Bedtime Practices and Language Development in Low-Risk Preterm and Full-Term Late Talkers: A Longitudinal Study in the Third Year of Life
by Mariagrazia Zuccarini, Martina Riva, Arianna Aceti, Luigi Corvaglia, Anat Scher, Annalisa Guarini and Alessandra Sansavini
Children 2024, 11(11), 1393; https://doi.org/10.3390/children11111393 (registering DOI) - 16 Nov 2024
Abstract
Background: Studies on night sleep and parental bedtime practices and their associations with language development in populations at risk of language delay and neonatal conditions, such as late talkers and preterm children, are scarce. Objectives: Our objective was to longitudinally examine [...] Read more.
Background: Studies on night sleep and parental bedtime practices and their associations with language development in populations at risk of language delay and neonatal conditions, such as late talkers and preterm children, are scarce. Objectives: Our objective was to longitudinally examine the development of night sleep (total night sleep difficulties, settling, night waking, and co-sleeping), parental bedtime practices (total parental bedtime practices, active physical comforting, encouraging autonomy, and leaving to cry), and expressive language (word and sentence production), and their associations in low-risk preterm and full-term late talkers from 31 to 37 months of age. Methods: Parents of 38 late talkers, 19 low-risk preterm and 19 full-term children, completed the Italian versions of the Infant Sleep Questionnaire, the Parental Interactive Bedtime Behavior Scale, and the MacArthur-Bates Communicative Development Inventory Words and Sentences Long Form. Results: Late talkers’ night sleep difficulties, such as settling to sleep and night waking, decreased over time, with low-risk preterm late talkers experiencing more night waking and co-sleeping than full-term peers. Parents reported that instances of active physical comforting and leaving to cry also decreased, with parents of low-risk preterm late talkers reporting higher active physical comforting scores than parents of full-term peers. Improvements in parental practices of encouraging autonomy were significantly associated with increased sentence production from 31 to 37 months. Conclusions: Findings highlight the importance of monitoring night sleep in preterm and full-term late talkers. They also suggest that populations vulnerable to sleep and language delays may particularly benefit from targeted interventions promoting autonomy in their bedtime routines, which, in turn, could support their language development trajectories. Full article
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Figure 1

Figure 1
<p>Longitudinal trajectories of mean ISQ scores (total score, settling, night waking, and co-sleeping) in low-risk preterm and full-term late talkers at 31 and 37 months.</p>
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13 pages, 1356 KiB  
Article
Protective Effect of Marine Peptide from Netunea arthritica cumingii Against Gentamicin-Induced Hair Cell Damage in Zebrafish
by Hongbao Zheng, Ranran Zhu, Yun Zhang, Kechun Liu, Qing Xia, Peihai Li, Xiaoyue Sun, Chen Sun and Shanshan Zhang
Mar. Drugs 2024, 22(11), 519; https://doi.org/10.3390/md22110519 (registering DOI) - 16 Nov 2024
Abstract
Auditory hair cell damage induced by aminoglycoside antibiotics (AmAn) leads to hearing loss, which has a serious effect on people’s mental and physical health. This ototoxicity is thought to be related with the excessive accumulation of reactive oxygen species (ROS) in hair cells. [...] Read more.
Auditory hair cell damage induced by aminoglycoside antibiotics (AmAn) leads to hearing loss, which has a serious effect on people’s mental and physical health. This ototoxicity is thought to be related with the excessive accumulation of reactive oxygen species (ROS) in hair cells. However, therapeutic agents that protect hair cells are limited. Marine peptides have been shown to have excellent potential applications in disease prevention and treatment. Therefore, this study investigated the protective effects of an active peptide from Neptunea arthritica cumingii against AmAn-induced hair cell damage using the model of hair cell damage zebrafish. We identified the number, ultrastructure, and function of hair cells using fluorescence probes and scanning electron microscopy. The uptake of AmAn, ROS level, mitochondrial permeability transition pore, and apoptosis in hair cells were also tested by fluorescence labeling and TUNEL assay. The molecular mechanism for hair cell protection exerted by the peptide was detected by a real-time quantitative PCR assay. The results indicated that the peptide suppressed the uptake of AmAn but did not damage the function of hair cells mediating hearing. It also prevented ROS accumulation, decreased the occurrence of apoptosis, and rescued the abnormal opening and expressions of mitochondrial permeability transition pore and genes related to antioxidants. The peptide may be an effective therapeutic agent for AmAn-induced ototoxicity. In the future, we plan to use mammalian models to further investigate the otoprotective effect of the peptide. Full article
(This article belongs to the Special Issue Zebrafish Models in Marine Drug Discovery)
17 pages, 4011 KiB  
Article
High-Performance Ammonia QCM Sensor Based on SnO2 Quantum Dots/Ti3C2Tx MXene Composites at Room Temperature
by Chong Li, Ran Tao, Jinqiao Hou, Huanming Wang, Chen Fu and Jingting Luo
Nanomaterials 2024, 14(22), 1835; https://doi.org/10.3390/nano14221835 (registering DOI) - 16 Nov 2024
Abstract
Ammonia (NH3) gas is prevalent in industrial production as a health hazardous gas. Consequently, it is essential to develop a straightforward, reliable, and stable NH3 sensor capable of operating at room temperature. This paper presents an innovative approach to modifying [...] Read more.
Ammonia (NH3) gas is prevalent in industrial production as a health hazardous gas. Consequently, it is essential to develop a straightforward, reliable, and stable NH3 sensor capable of operating at room temperature. This paper presents an innovative approach to modifying SnO2 colloidal quantum dots (CQDs) on the surface of Ti3C2Tx MXene to form a heterojunction, which introduces a significant number of adsorption sites and enhances the response of the sensor. Zero-dimensional (0D) SnO2 quantum dots and two-dimensional (2D) Ti3C2Tx MXene were prepared by solvothermal and in situ etching methods, respectively. The impact of the mass ratio between two materials on the performance was assessed. The sensor based on 12 wt% Ti3C2Tx MXene/SnO2 composites demonstrates excellent performance in terms of sensitivity and response/recovery speed. Upon exposure to 50 ppm NH3, the frequency shift in the sensor is −1140 Hz, which is 5.6 times larger than that of pure Ti3C2Tx MXene and 2.8 times higher than that of SnO2 CQDs. The response/recovery time of the sensor for 10 ppm NH3 was 36/54 s, respectively. The sensor exhibited a theoretical detection limit of 73 ppb and good repeatability. Furthermore, a stable sensing performance can be maintained after 30 days. The enhanced sensor performance can be attributed to the abundant active sites provided by the accumulation/depletion layer in the Ti3C2Tx/SnO2 heterojunction, which facilitates the adsorption of oxygen molecules. This work promotes the gas sensing application of MXenes and provides a way to improve gas sensing performance. Full article
18 pages, 2525 KiB  
Article
Identifying Herbal Candidates and Active Ingredients Against Postmenopausal Osteoporosis Using Biased Random Walk on a Multiscale Network
by Boyun Jang, Youngsoo Kim, Jungbin Song, Young-Woo Kim and Won-Yung Lee
Int. J. Mol. Sci. 2024, 25(22), 12322; https://doi.org/10.3390/ijms252212322 (registering DOI) - 16 Nov 2024
Abstract
Postmenopausal osteoporosis is a major global health concern, particularly affecting aging women, and necessitates innovative treatment options. Herbal medicine, with its multi-compound, multi-target characteristics, offers a promising approach for complex diseases. In this study, we applied multiscale network and random walk-based analyses to [...] Read more.
Postmenopausal osteoporosis is a major global health concern, particularly affecting aging women, and necessitates innovative treatment options. Herbal medicine, with its multi-compound, multi-target characteristics, offers a promising approach for complex diseases. In this study, we applied multiscale network and random walk-based analyses to identify candidate herbs and their active ingredients for postmenopausal osteoporosis, focusing on their underlying mechanisms. A dataset of medicinal herbs, their active ingredients, and protein targets was compiled, and diffusion profiles were calculated to assess the propagation effects. Through correlation analysis, we prioritized herbs based on their relevance to osteoporosis, identifying the top candidates like Benincasae Semen, Glehniae Radix, Corydalis Tuber, and Houttuyniae Herba. Gene Set Enrichment Analysis (GSEA) revealed that the 49 core protein targets of these herbs were significantly associated with pathways related to inflammation, osteoclast differentiation, and estrogen metabolism. Notably, compounds such as falcarindiol from Glehniae Radix and tetrahydrocoptisine from Corydalis Tuber—previously unstudied for osteoporosis—were predicted to interact with inflammation-related proteins, including IL6, IL1B, and TNF, affecting key biological processes like apoptosis and cell proliferation. This study advances the understanding of herbal therapies for osteoporosis and offers a framework for discovering novel therapeutic agents. Full article
16 pages, 6572 KiB  
Article
Enhancing β-Galactosidase Performance for Galactooligosaccharides Preparation via Strategic Glucose Re-Tunneling
by Jihua Zhao, Dandan Niu, Jiaqi Liu, Zhuolin Jin, Nokuthula Peace Mchunu, Suren Singh and Zhengxiang Wang
Int. J. Mol. Sci. 2024, 25(22), 12316; https://doi.org/10.3390/ijms252212316 (registering DOI) - 16 Nov 2024
Abstract
Abstract: This study focuses on the characterization and re-engineering of glucose transport in β-galactosidase (BglD) to enhance its catalytic efficiency. Computational prediction methods were employed to identify key residues constituting access tunnels for lactose and glucose, revealing distinct pockets for both substrates. In [...] Read more.
Abstract: This study focuses on the characterization and re-engineering of glucose transport in β-galactosidase (BglD) to enhance its catalytic efficiency. Computational prediction methods were employed to identify key residues constituting access tunnels for lactose and glucose, revealing distinct pockets for both substrates. In silico simulated saturation mutagenesis of residues T215 and T473 led to the identification of eight mutant variants exhibiting potential enhancements in glucose transport. Site-directed mutagenesis at T215 and T473 resulted in mutants with consistently enhanced specific activities, turnover rates, and catalytic efficiencies. These mutants also demonstrated improved galactooligosaccharide (GOS) synthesis, yielding an 8.1–10.6% enhancement over wild-type BglD yield. Structural analysis revealed that the mutants exhibited transformed configurations and localizations of glucose conduits, facilitating expedited glucose release. This study’s findings suggest that the re-engineered mutants offer promising avenues for enhancing BglD’s catalytic efficiency and glucose translocation, thereby improving GOS synthesis. By-product (glucose) re-tunneling is a viable approach for enzyme tunnel engineering and holds significant promise for the molecular evolution of enzymes. Full article
18 pages, 11109 KiB  
Article
Effects of Sarcosine (N-methylglycine) on NMDA (N-methyl-D-aspartate) Receptor Hypofunction Induced by MK801: In Vivo Calcium Imaging in the CA1 Region of the Dorsal Hippocampus
by Yi-Tse Hsiao, Ching-Yuan Chang, Ting-Yen Lee, Wan-Ting Liao, Wen-Sung Lai and Fang-Chia Chang
Brain Sci. 2024, 14(11), 1150; https://doi.org/10.3390/brainsci14111150 (registering DOI) - 16 Nov 2024
Abstract
Background: Hypofunction of the glutamate system in the brain is one of the pathophysiological hypotheses for schizophrenia. Accumulating animal and clinical studies show that sarcosine (N-methylglycine), a glycine transporter-1 inhibitor, is effective in ameliorating the negative and cognitive symptoms of schizophrenia. The aims [...] Read more.
Background: Hypofunction of the glutamate system in the brain is one of the pathophysiological hypotheses for schizophrenia. Accumulating animal and clinical studies show that sarcosine (N-methylglycine), a glycine transporter-1 inhibitor, is effective in ameliorating the negative and cognitive symptoms of schizophrenia. The aims of the present study were to observe the effects of sarcosine on neuronal activity in the dorsal CA1 (dCA1) hippocampal neurons within an NMDA receptor hypofunction model induced by MK801. Methods: We applied in vivo calcium imaging to observe the dynamics of fluorescence from the dCA1 hippocampal neurons when the mice were exploring in an open field. Using this tool, we directly measured and compared neuronal properties between sarcosine-treated and untreated mice. At the same time, the physiological function of the neurons was also quantified by measuring their place fields. Results: Our data demonstrated that MK-801 (0.2 mg/kg) diminished the fluorescence intensity of dCA1 neurons that had been genetically modified with a calcium indicator. MK-801 also significantly increased the correlation coefficient between the fluorescence dynamics of pairs of cells, a feature that may be linked to the symptom of disorganization in human patients with schizophrenia. The spatial correlations of place fields in the mice were impaired by MK-801 as well. Injected sarcosine (500 mg or 1000 mg/kg) significantly alleviated the abovementioned abnormalities. Conclusions: Our data provide evidence to support the use of sarcosine to alleviate symptoms of schizophrenia, especially hippocampus-related functions. Full article
(This article belongs to the Special Issue Advanced Clinical Diagnosis, Evaluation, and Treatment of Psychosis)
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Figure 1

Figure 1
<p>Examples of fluorescence intensity of dorsal CA1 neurons from mouse #3 after administration of MK-801 and sarcosine. (<b>A</b>) Histology slice for the location of GRIN lens implantation. (<b>B</b>) Experimental schedule of a session. The animal was explored in an identical open field in trials A and B. The drugs were injected before trial B. (<b>C</b>) Stacked image that was background-subtracted and movement-corrected (MC) by MIN1PIPE [<a href="#B26-brainsci-14-01150" class="html-bibr">26</a>] of one recording session. The unit of the traces are normalized “processed calcium traces (PCT)”, which are normalized calcium signals after neural enhancement and denoising by MIN1PIPE (<b>D</b>) Examples of fluorescence traces. (<b>E</b>–<b>H</b>) Example of fluorescence intensities of the same animal under the treatment of PBS + PBS, MK-801 + PBS, MK-801 + sarcosine (SAR500, 500 mg/kg), and MK-801 + sarcosine (SAR1000, 1000 mg/kg). (<b>I</b>) Mean delta fluorescence intensities (trial B–A) of neurons of all animals (Mean ± SEM) (Each single cell was treated as a sample for bootstrapping before statistical analysis). **: vs. PBS + PBS; ##: vs MK-801 + PBS; %%: vs MK-801 + SAR500 indicates significant difference (<span class="html-italic">p</span> &lt; 0.01), as determined using the Bootstrap method followed by Tukey’s post hoc test for multiple comparisons.</p>
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<p>Fluorescence intensity ratio of trial B/trial A of grouped cell ensembles. (<b>A</b>–<b>C</b>) Cumulative distribution of the intensity ratio which is randomly sampled and averaged 20 intensity traces 1000 times in mice #1 to #3, respectively. The manipulations of PBS + PBS, MK-801 + PBS, MK-801 + SAR500, and MK-801 + SAR1000 are represented by black, gray, red, and blue lines. (<b>D</b>–<b>F</b>) Intensity ratio, which is randomly selected and averaged 30 intensity traces 1000 times. (<b>G</b>–<b>I</b>) Intensity ratio, which is randomly selected and averaged 50 intensity traces 1000 times.</p>
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<p>Examples of dorsal CA1 cell–cell correlation matrixes from mouse #3. (<b>A</b>–<b>D</b>) Cell–cell correlation matrixes after the administration of PBS + PBS, MK-801 + PBS, MK-801 + SAR500, and MK-801 + SAR1000, respectively. (<b>E</b>) Delta correlation coefficient (trial B–trial A) of pairwise neurons of all animals (Mean ± SEM) (Each single cell was treated as a sample for bootstrapping before statistical analysis). **: vs. PBS + PBS; ##: vs. MK-801 + PBS; %%: vs. MK-801 + SAR500 indicates significant difference (<span class="html-italic">p</span> &lt; 0.01), as determined using the Bootstrap method followed by Tukey’s post hoc test for multiple comparisons.</p>
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<p>Examples of maximum fluorescence intensity maps from a fluorescence-positive cell in dorsal CA1. (<b>A</b>) Maximum fluorescence intensity maps of an example dorsal CA1 fluorescence positive cell are depicted by colors, where warm colors represent strong fluorescence signals and white represents weak signals. The gray line represents the walking trajectory of the animal (mouse #1). (<b>B</b>) Spatial correlation between trial A and trial B in neurons from all animals (Mean ± SEM) (Each single cell was treated as a sample for bootstrapping before statistical analysis). **: vs. PBS + PBS; ##: vs. MK-801 + PBS; %%: vs. MK-801 + SAR500 indicates significant difference (<span class="html-italic">p</span> &lt; 0.01), as determined using the Bootstrap method followed by Tukey’s post hoc test for multiple comparisons.</p>
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12 pages, 4933 KiB  
Perspective
Urban Green Spaces and Healthy Living: A Landscape Architecture Perspective
by Alessio Russo
Urban Sci. 2024, 8(4), 213; https://doi.org/10.3390/urbansci8040213 (registering DOI) - 16 Nov 2024
Abstract
This paper examines the essential role of urban green spaces in fostering healthy living from a landscape architecture perspective. Health goes beyond the mere absence of disease to include physical, mental, and social wellbeing, all of which are greatly enhanced by accessible green [...] Read more.
This paper examines the essential role of urban green spaces in fostering healthy living from a landscape architecture perspective. Health goes beyond the mere absence of disease to include physical, mental, and social wellbeing, all of which are greatly enhanced by accessible green spaces. By synthesising existing literature, this paper shows that urban green spaces have strong positive associations with health outcomes, especially in urban settings where environmental stressors are pronounced. The paper stresses the importance of designing attractive and accessible green spaces that encourage physical activity, mental wellbeing, and social interaction, addressing public health issues such as obesity and mental health disorders. In addition to physical and mental health benefits, the paper explores the potential of local food production through edible green infrastructure, such as community gardens, which can significantly improve diet and nutrition. Additionally, the study discusses disparities in the access to quality green spaces, particularly between the Global North and South, and advocates for equitable design strategies that serve diverse populations. Integrating evidence-based approaches into landscape architecture, the paper argues for the establishment of urban green spaces as essential elements of public health infrastructure. Finally, the paper calls for future research and policy efforts to maximise the health benefits of urban green spaces and improve the quality of life in urban environments. Full article
14 pages, 768 KiB  
Article
Exploring Nonlinear Dynamics in Intertidal Water Waves: Insights from Fourth-Order Boussinesq Equations
by Hassan Almusawa, Musawa Yahya Almusawa, Adil Jhangeer and Zamir Hussain
Axioms 2024, 13(11), 793; https://doi.org/10.3390/axioms13110793 (registering DOI) - 16 Nov 2024
Abstract
The fourth-order nonlinear Boussinesq water wave equation, which describes the propagation of long waves in the intertidal zone, is investigated in this study. The exact wave patterns of the equation were computed using the tanh method. As stability decreased, soliton [...] Read more.
The fourth-order nonlinear Boussinesq water wave equation, which describes the propagation of long waves in the intertidal zone, is investigated in this study. The exact wave patterns of the equation were computed using the tanh method. As stability decreased, soliton wave structures were derived using similarity transformations. Numerical simulations supported these findings. The tanh method introduced a Galilean modification, leading to the discovery of several new exact solutions. Subsequently, the fourth-order nonlinear Boussinesq wave equation was transformed into a planar dynamical system using the travelling wave transformation. The quasi-periodic, cyclical, and nonlinear behaviors of the analyzed equation were particularly examined. Numerical simulations revealed that varying the physical parameters impacts the system’s nonlinear behavior. Graphs represent all possible examples of phase portraits in terms of these parameters. Furthermore, the study was proven to be highly beneficial for addressing issues such as shock waves and highly active travelling wave processes. Sensitivity analysis theory and the Lyapunov exponent were employed, offering a wide variety of linear periodic and first-frequency periodic characteristics. Sensitivity analysis and multistability analysis of the Boussinesq water wave equation were thoroughly investigated. Full article
16 pages, 1949 KiB  
Article
Peptide-Functionalized Gold Nanoparticles as Organocatalysts for Asymmetric Aldol Reactions
by Thabo Peme, Dean Brady, Ndivhuwo P. Shumbula, Khanani Machumele, Nosipho Moloto, Taryn Adams and Maya M. Makatini
Catalysts 2024, 14(11), 826; https://doi.org/10.3390/catal14110826 (registering DOI) - 16 Nov 2024
Abstract
The use of high catalyst loading is required for most of the organocatalyzed asymmetric aldol reactions in organic synthesis, and this often presents challenges during purification and difficulties in catalyst recovery from the reaction mixture. The immobilization of the catalyst onto gold nanoparticles [...] Read more.
The use of high catalyst loading is required for most of the organocatalyzed asymmetric aldol reactions in organic synthesis, and this often presents challenges during purification and difficulties in catalyst recovery from the reaction mixture. The immobilization of the catalyst onto gold nanoparticles (AuNPs) can change the structural conformations of the catalyst, thereby improving its catalytic activity and reusability. Herein we report on the synthesis of aldolase mimetic peptide coupled to gold nanoparticles (AuNPs) as efficient organocatalysts for asymmetric aldol reaction. AuNPs were synthesized using the Turkevich method. The conjugation of the peptide to AuNPs was characterized using surface plasmon resonance (SPR), Raman and X-ray photoelectron spectroscopy, and transmission electron microscopy (TEM) was used for particle size determination. The produced nanoparticles, whose sizes depended on the reduction method, were quasi-spherical with a relatively narrow size distribution. The peptide–AuNP conjugates were evaluated for aldol reaction catalytic activity between carbonyls p-nitrobenzaldehyde and cyclohexanone. The products were obtained with good yields (up to 85%) and enantioselectivity (up to 94%). The influence of organic solvents, pH and buffer solutions was also investigated. The results showed that the buffer solutions regulated the colloidal stability of AuNPs, resulting in a significant enhancement in the catalytic rate of the peptide–AuNP conjugate. Full article
(This article belongs to the Section Catalysis in Organic and Polymer Chemistry)
24 pages, 1826 KiB  
Review
Mineralocorticoid Receptor and Sleep Quality in Chronic Kidney Disease
by Juan de la Puente-Aldea, Oscar Lopez-Llanos, Daniel Horrillo, Hortensia Marcos-Sanchez, Sandra Sanz-Ballesteros, Raquel Franco, Frederic Jaisser, Laura Senovilla and Roberto Palacios-Ramirez
Int. J. Mol. Sci. 2024, 25(22), 12320; https://doi.org/10.3390/ijms252212320 (registering DOI) - 16 Nov 2024
Abstract
The classical function of the mineralocorticoid receptor (MR) is to maintain electrolytic homeostasis and control extracellular volume and blood pressure. The MR is expressed in the central nervous system (CNS) and is involved in the regulation of the hypothalamic–pituitary–adrenal (HPA) axis as well [...] Read more.
The classical function of the mineralocorticoid receptor (MR) is to maintain electrolytic homeostasis and control extracellular volume and blood pressure. The MR is expressed in the central nervous system (CNS) and is involved in the regulation of the hypothalamic–pituitary–adrenal (HPA) axis as well as sleep physiology, playing a role in the non-rapid eye movement (NREM) phase of sleep. Some patients with psychiatric disorders have very poor sleep quality, and a relationship between MR dysregulation and this disorder has been found in them. In addition, the MR is involved in the regulation of the renal peripheral clock. One of the most common comorbidities observed in patients with chronic kidney disease (CKD) is poor sleep quality. Patients with CKD experience sleep disturbances, including reduced sleep duration, sleep fragmentation, and insomnia. To date, no studies have specifically investigated the relationship between MR activation and CKD-associated sleep disturbances. However, in this review, we analyzed the environment that occurs in CKD and proposed two MR-related mechanisms that may be responsible for these sleep disturbances: the circadian clock disruption and the high levels of MR agonist observed in CKD. Full article
(This article belongs to the Special Issue Nuclear Receptors in Diseases)
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Graphical abstract

Graphical abstract
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<p>Hypothalamic–pituitary–adrenal (HPA) axis components and regulations. The delivery of corticotropin releasing hormone (CRH) by the hypothalamus to the pituitary gland induces the secretion of adrenocorticotropic hormone (ACTH). ACTH leads to the adrenal glands producing cortisol and aldosterone, which mediates negative feedback to the hypothalamus through the mineralocorticoid receptor (MR) and the glucocorticoid receptor (GR).</p>
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<p>Circadian clock pathway. CLOCK: Circadian locomotor output cycles kaput, BMAL1: brain and muscle aryl hydrocarbon receptor nuclear-like 1, E-box: enhancer box, CRY: cryptochrome, PER: period circadian protein homolog, ROR: retinoid-related orphan receptor, REV-ERBα: reverse erythroblastosis virus α, CK1δ/ε: Casein Kinase 1 isoforms δ/ε, RRE: ROR response element.</p>
Full article ">Figure 3
<p>Kidney function circadian coupling. Representation of the circadian time (black line) with the peak of Na+/K+ excretion, the peak of blood pressure, and the peak of adrenal hormone release. Adrenal hormones: cortisol and aldosterone.</p>
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<p>Potential mechanisms by which chronic kidney disease (CKD)-associated mineralocorticoid receptor (MR) dysregulation may lead to sleep disturbances. (<b>A</b>) The electrolytic imbalance observed in CKD through the overactivation of the MR could disrupt the circadian clock, which controls sleep and the hypothalamic-pituitary-adrenal (HPA) axis. Then, the altered HPA axis could dysregulate non-REM sleep phase (NREM) and rapid eye movement sleep phase (REM). (<b>B</b>) Hyperaldosteronemia and hypercortisolemia associated with CKD could lead to sleep disturbances in two ways. On one hand, through the HPA dysregulation and the consequent over occupancy of the glucocorticoid receptor (GR). On the other hand, increased levels of cortisol and aldosterone, as well as HPA axis dysregulation, lead to overactivation of the central GR and MR and entrance into the SWS phase.SWS: Slow-Wave Sleep.</p>
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19 pages, 709 KiB  
Article
Broad Neutralization Capacity of an Engineered Thermostable Three-Helix Angiotensin-Converting Enzyme 2 Polypeptide Targeting the Receptor-Binding Domain of SARS-CoV-2
by Davide Cavazzini, Elisabetta Levati, Saveria Germani, Bao Loc Ta, Lara Monica, Angelo Bolchi, Gaetano Donofrio, Valentina Garrapa, Simone Ottonello and Barbara Montanini
Int. J. Mol. Sci. 2024, 25(22), 12319; https://doi.org/10.3390/ijms252212319 (registering DOI) - 16 Nov 2024
Abstract
The mutational drift of SARS-CoV-2 and the appearance of multiple variants, including the latest Omicron variant and its sub-lineages, has significantly reduced (and in some cases abolished) the protective efficacy of Wuhan spike-antigen-based vaccines and therapeutic antibodies. One of the most functionally constrained [...] Read more.
The mutational drift of SARS-CoV-2 and the appearance of multiple variants, including the latest Omicron variant and its sub-lineages, has significantly reduced (and in some cases abolished) the protective efficacy of Wuhan spike-antigen-based vaccines and therapeutic antibodies. One of the most functionally constrained and thus largely invariable regions of the spike protein is the one involved in the interaction with the ACE2 receptor mediating the cellular entry of SARS-CoV-2. Engineered ACE2, both as a full-length protein or as an engineered polypeptide fragment, has been shown to be capable of preventing the host-cell binding of all viral variants and to be endowed with potent SARS-CoV-2 neutralization activity both in vitro and in vivo. Here, we report on the biochemical and antiviral properties of rationally designed ACE2 N-terminal, three-helix fragments that retain a native-like conformation. One of these fragments, designated as PRP8_3H and produced in recombinant form, bears structure-stabilizing and binding-affinity enhancing mutations in a-helix-I and in both a-helix I and II, respectively. While the native-like, unmodified three a-helices ACE2 fragment proved to be thermally unstable and without any detectable pseudovirion neutralization capacity, PRP8_3H was found to be highly thermostable and capable of binding to the SARS-CoV-2 spike receptor-binding domain with nanomolar affinity and to neutralize both Wuhan and Omicron spike-expressing pseudovirions at (sub)micromolar concentrations. PRP8_3H thus lends itself as a highly promising ACE2 decoy prototype suitable for a variety of formulations and prophylactic applications. Full article
(This article belongs to the Section Biochemistry)
21 pages, 4816 KiB  
Article
Roscovitine, a CDK Inhibitor, Reduced Neuronal Toxicity of mHTT by Targeting HTT Phosphorylation at S1181 and S1201 In Vitro
by Hongshuai Liu, Ainsley McCollum, Asvini Krishnaprakash, Yuxiao Ouyang, Tianze Shi, Tamara Ratovitski, Mali Jiang, Wenzhen Duan, Christopher A. Ross and Jing Jin
Int. J. Mol. Sci. 2024, 25(22), 12315; https://doi.org/10.3390/ijms252212315 (registering DOI) - 16 Nov 2024
Abstract
Huntington’s disease (HD) is an autosomal dominant neurodegenerative disease caused by a single mutation in the huntingtin gene (HTT). Normal HTT has a CAG trinucleotide repeat at its N-terminal within the range of 36. However, once the CAG repeats exceed 37, the mutant [...] Read more.
Huntington’s disease (HD) is an autosomal dominant neurodegenerative disease caused by a single mutation in the huntingtin gene (HTT). Normal HTT has a CAG trinucleotide repeat at its N-terminal within the range of 36. However, once the CAG repeats exceed 37, the mutant gene (mHTT) will encode mutant HTT protein (mHTT), which results in neurodegeneration in the brain, specifically in the striatum and other brain regions. Since the mutation was discovered, there have been many research efforts to understand the mechanism and develop therapeutic strategies to treat HD. HTT is a large protein with many post-translational modification sites (PTMs) and can be modified by phosphorylation, acetylation, methylation, sumoylation, etc. Some modifications reduced mHTT toxicity both in cell and animal models of HD. We aimed to find the known kinase inhibitors that can modulate the toxicity of mHTT. We performed an in vitro kinase assay using HTT peptides, which bear different PTM sites identified by us previously. A total of 368 kinases were screened. Among those kinases, cyclin-dependent kinases (CDKs) affected the serine phosphorylation on the peptides that contain S1181 and S1201 of HTT. We explored the effect of CDK1 and CDK5 on the phosphorylation of these PTMs of HTT and found that CDK5 modified these two serine sites, while CDK5 knockdown reduced the phosphorylation of S1181 and S1201. Modifying these two serine sites altered the neuronal toxicity induced by mHTT. Roscovitine, a CDK inhibitor, reduced the p-S1181 and p-S1201 and had a protective effect against mHTT toxicity. We further investigated the feasibility of the use of roscovitine in HD mice. We confirmed that roscovitine penetrated the mouse brain by IP injection and inhibited CDK5 activity in the brains of HD mice. It is promising to move this study to in vivo for pre-clinical HD treatment. Full article
(This article belongs to the Section Molecular Neurobiology)
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<p>Kinase assays identified upstream kinases modifying the serine of HTT peptides in vitro. In vitro kinase assay was used to screen the kinase targeting HTT peptide bearing serine 1181, serine 1201, and serine 2653 of HTT. (<b>A</b>) Kinases targeting the serine 1181 of the HTT peptide. (<b>B</b>) Kinases targeting the serine 1201 of the HTT peptide. (<b>C</b>) Kinases targeting the serine 2653 of the HTT peptide. CDK1 is highlighted by blue rectangles and CDK5/p25 by red rectangles. RBC, red blood cell substrate. Dotted lines indicate the 5% cut-off of enzyme activity used for the kinase screening.</p>
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<p>HTT peptides as potential as targets for CDKs. (<b>A</b>) The amino acid sequences surrounding serine of 1181, 1201, and 2653 of HTT from different species. S/T-P-x-K/R is a consensus site for both CDK1 and CDK5, which means that the amino acid of S or T followed by P-x-K/R could be phosphorylated by CDK1 and CDK5. (S = serine; T = threonine; P = proline; K = lysine; R = arginine; x is any amino acid). It is well conserved in vertebrates for S1181 and S1201 of the HTT sequence, but not S2653. (<b>B</b>) CDKs target serine 1181 of the HTT peptide. (<b>C</b>) CDKs target serine 1201 of HTT peptide. CDK1 is highlighted by blue rectangles and CDK5/p25 by red rectangles. RBC, red blood cell substrate. Dotted lines indicate the 1% cut-off of enzyme activity used for the kinase screening.</p>
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<p>The effect of knocking down CDK5 on the phosphorylation of S1181 and S1201 of mHTT. HEK293 cells were co-transfected with a plasmid expressing full-length mutant huntingtin with 82Q (FL-82Q) and siRNA targeting human CDK5 for 24 h. The expression level of CDK5, phosphorylated S1181-HTT (p-S1181), and phosphorylated S1201-HTT (p-S1201) were detected by western blot. (<b>A</b>) The representative western blot for CDK5. (<b>B</b>) The quantification of CDK5 expression. (<b>C</b>) The representative western blot for p-S1181-HTT. (<b>D</b>) The quantification of p-S1181-HTT expression. (<b>E</b>) The representative western blot for p-S1201-HTT. (<b>F</b>) The quantification of p-S1201-HTT expression. The experiment was repeated by at least two different analysts. Each experiment had <span class="html-italic">n</span> = 3. One representative experiment is presented. 2166 is the anti-HTT antibody (MAB2166, Millipore). RNAi = pooled siRNA targeting human CDK5. A two-tailed Student <span class="html-italic">t</span>-test was used. * <span class="html-italic">p</span> &lt; 0.05; ** <span class="html-italic">p</span> &lt; 0.01.</p>
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<p>The effect of CDK5 overexpression on S1181 of mHTT. HEK293 cells were co-transfected with HTT plasmid FL-82Q and a plasmid expressing human CDK5 for 24 h. The expression levels of CDK5, p-S1181, and p-S1201 were detected by western blot. (<b>A</b>) The representative western blot for CDK5, p-S1181, 2166, and MW1. (<b>B</b>) The quantification of CDK5 expression. (<b>C</b>,<b>D</b>) The quantification of p-S1181 expression. (<b>E</b>) The quantification of total huntingtin (MAB2166) expression. (<b>F</b>) The quantification of mutant huntingtin (MW1) expression. The experiment was repeated by at least two different analysts. Each experiment had n = 3. One representative experiment is presented. 2166 is the anti-HTT antibody (MAB2166). MW1 is the anti-HTT antibody that binds to mutant huntingtin (clone MW1). RNAi = siRNA targeting human CDK5. A two-tailed Student <span class="html-italic">t</span>-test was used. ** <span class="html-italic">p</span> &lt; 0.01; *** <span class="html-italic">p</span> &lt; 0.001.</p>
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<p>CDK5 level altered cell toxicity induced by mHTT. The effect of CDK5 overexpression or knocking down was evaluated in mouse striatal cells with different poly Q (SThdh <sup>Q7/Q7</sup> or SThdh <sup>Q111/Q111</sup>). Cells were transfected with either a plasmid expressing human CDK5 or pooled siRNA targeting mouse CDK5 for 24 h. Cell death was measured with CytoTox-Glo cytotoxicity assay kit (Promega). The experiment was repeated by at least two different analysts. Each experiment had n = 3. One representative experiment is presented. Two-way ANOVA with Tukey’s multiple comparation was used for analysis. * <span class="html-italic">p</span> &lt; 0.05; ** <span class="html-italic">p</span> &lt; 0.01; *** <span class="html-italic">p</span> &lt; 0.001.</p>
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<p>Phospho-null modification of S1181 and S1201 of mHTT altered the mHTT-induced cell toxicity. S1181 and S1201 in the plasmid of FL-82Q were artificially modified to alanine (A). (<b>A</b>) Modified plasmids were transiently transfected into HEK293 cells for 72 h, and cell toxicity was measured by caspase3/7 activity. (<b>B</b>) The modified plasmids were transient transfected in primary cortical neurons, and cell death was analyzed by nuclei condensation assay. The experiment was repeated by at least two different analysts. Each experiment had n = 3. One representative experiment is presented. One-way ANOVA with Dunnett’s multiple comparation was used for analysis. * <span class="html-italic">p</span> &lt; 0.05; ** <span class="html-italic">p</span> &lt; 0.01; *** <span class="html-italic">p</span> &lt; 0.001.</p>
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<p>Roscovitine protected cells from mHTT-induced toxicity. Roscovitine was used in different HD cell models to evaluate its effect on mHTT-induced toxicity. (<b>A</b>). The effect of roscovitine on mHTT-induced toxicity in SThdh cells expressing Q111 cells. SThdh <sup>Q111/Q111</sup> cells were treated with roscovitine for 24 h under serum withdrawal conditions, and cell toxicity was measured using a CytoTox kit. (<b>B</b>). The effect of roscovitine on mHTT-induced toxicity in primary cortical neuronal HD cell model. Primary cultured cortical neurons were transiently transfected with plasmids expressing either normal Q (23Q) or poly Q (82Q) for 4 h and then treated with or without roscovitine for 48 h. A nuclei condensation assay was used to evaluate cell death. The experiment was repeated by at least two different analysts. Each experiment had <span class="html-italic">n</span> = 3. One representative experiment is presented. W/O = serum withdrawal. One-way ANOVA with Dunnett’s multiple comparation was used for analysis. * <span class="html-italic">p</span> &lt; 0.05; ** <span class="html-italic">p</span> &lt; 0.01.</p>
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<p>Roscovitine reduced the phosphorylation of S1181 and S1201 of mHTT. Roscovitine reduced p-S1181-HTT and p-S1201-HTT in vitro by inhibiting CDK5 but not CDK1. (<b>A</b>) The representative western blot for p-S1181 in HEK293 cells transfected with a plasmid expressing FL-82Q and treated with or without roscovitine for 48 h. (<b>B</b>) The representative western blot for p-S1201 in HEK293 cells transfected with a plasmid expressing FL-82Q and treated with or without roscovitine for 48 h. (<b>C</b>) The representative western blot for CDK5 in HEK293 cells transfected with a plasmid expressing FL-82Q and treated with or without roscovitine for 48 h. (<b>D</b>) The representative western blot for CDK1 in HEK293 cells transfected with a plasmid expressing FL-82Q and treated with or without roscovitine for 48 h. (<b>E</b>) Quantification of p-S1181 in A. (<b>F</b>) Quantification of p-S1201 in B. (<b>G</b>) Quantification of CDK5 in C. (<b>H</b>) Quantification of CDK1 in D. The experiment was repeated by at least two different analysts. Each experiment had n = 3. One representative experiment is presented. Ros~ = Roscovitine. A two-tailed Student <span class="html-italic">t</span>-test was used. * <span class="html-italic">p</span> &lt; 0.05; ** <span class="html-italic">p</span> &lt; 0.01.</p>
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<p>Roscovitine penetrated the mouse brain and inhibited CDK5 activity in the zQ175 HD mouse brain. Variant doses of roscovitine were injected into 4-month-old mice through intraperitoneal injection (IP). Plasma and brain samples were collected at different time points after injection. The concentration of roscovitine was measured by LCMS/MS. (<b>A</b>) Brain concentration of roscovitine at different time points after acute IP injection with variant doses. Each group has 4–5 mice. (<b>B</b>) The CDK5 activity in the brain of mice injected with roscovitine for three weeks. Two doses of roscovitine were injected into 4-month-old zQ175HD mice by IP daily for three weeks. Twenty-four hours after the last injection, the mouse brain samples were collected, and the CDK5 activity was measured using a commercial kit from Promega. Animal number is indicated in the bar graph for each group. R-25 = 25 mg/kg of roscovitine. R-50 = 50 mg/kg of roscovitine. One-way ANOVA with Fish’s LSD was used for analysis. * <span class="html-italic">p</span> &lt; 0.05; ** <span class="html-italic">p</span> &lt; 0.01.</p>
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<p>Tolerability of mice injected with roscovitine by IP administration. (<b>A</b>) The body weight loss of zQ175 HD mice injected with roscovitine. (<b>B</b>) The stride length (by CatWalk) in zQ175 HD mice before and after being injected with roscovitine. Roscovitine was injected by IP daily for three weeks. Animal number for each group is indicated in the bar graphs. V = Vehicle, R = roscovitine. R-25 = 25 mg/kg of roscovitine. R-50 = 50 mg/kg of roscovitine. One-way ANOVA with Fish’s LSD was used for analysis.</p>
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<p>Molecular neurobiological measurement in the brain of zQ175 HD mice injected with roscovitine by IP. Brain samples were collected as previously described. The cortex was dissected, and lysates were made for western blot analysis. (<b>A</b>) The expression of a pan-neuronal marker, NeuN. (<b>B</b>) The expression of astrocyte marker GFAP. (<b>C</b>) The expression of microglial marker IBA1. (<b>D</b>) The expression of mHTT marker MW1. (<b>E</b>) The quantification of NeuN. (<b>F</b>) The quantification of GFAP. (<b>G</b>) The quantification of IBA1. (<b>H</b>) The quantification of MW1. Animal number is indicated in the bar graph for each group. Veh~ = Vehicle, R25 = 25 mg/kg of roscovitine. R50 = 50 mg/kg of roscovitine. One-way ANOVA with Fish’s LSD was used for analysis.</p>
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26 pages, 869 KiB  
Article
Integrating Morpho-Physiological, Biochemical, and Molecular Genotyping for Selection of Drought-Tolerant Pigeon Pea (Cajanus cajan L.) Genotypes at Seedling Stage
by Benjamin O. Ouma, Kenneth Mburu, Geoffrey K. Kirui, Edward K. Muge and Evans N. Nyaboga
Plants 2024, 13(22), 3228; https://doi.org/10.3390/plants13223228 (registering DOI) - 16 Nov 2024
Abstract
Pigeon pea (Cajanus cajan (L.) Millsp.), a potential legume as an economic source of protein, is commonly cultivated in tropical and subtropical regions of the world. It possesses medicinal properties and acts as a cash crop, benefiting low-income farmers economically. The identification [...] Read more.
Pigeon pea (Cajanus cajan (L.) Millsp.), a potential legume as an economic source of protein, is commonly cultivated in tropical and subtropical regions of the world. It possesses medicinal properties and acts as a cash crop, benefiting low-income farmers economically. The identification of pigeon peas exhibiting drought tolerance has become crucial in addressing water scarcity issues in the agriculture sector. In addition, exploring the genetic diversity among genotypes is important for conservation, management of genetic resources, and breeding programs. The aim of this study was to evaluate the morpho-physiological and biochemical responses of selected pigeon pea genotypes under pot-induced water stress conditions through different field capacities as well as the genetic diversity using start codon targeted (SCoT) markers. A significant variation was observed for the physiological traits studied. The accumulation of fresh weight (FW) and dry weight (DW) was significantly reduced in moderate and severe drought stress conditions. The lowest % DW decrease was found in LM (35.39%), KAT (39.43%), and SM (46.98%) than other genotypes at severe drought stress. Analyses of physiological responses including the photosynthetic efficiency (Phi2), the chlorophyll content (SPAD), and the relative water content (RWC) revealed positive and negative correlations with various parameters, reflecting the impact of drought stress on the chlorophyll content. The results revealed that biochemical traits including the total phenolic content, soluble sugars, proline, total protein, total amino acids, and free amino acids were variably and significantly increased under water stress. Antioxidant enzyme activity levels, specifically ascorbate peroxidase (APX) and catalase, varied among the genotypes and in response to severe water stress, offering further insights into adaptive responses. The eight genotypes analysed by use of 20 SCoT markers revealed 206 alleles and an average of 10.3 alleles per locus. Genetic similarity ranged from 0.336 to 0.676, clustering the pigeon pea genotypes into two major groups by the unweighted pair group method of arithmetic averages (UPGMA) cluster analysis. Principal coordinate analysis (PCoA) explained 43.11% of genetic variation and based on analysis of molecular variance, a high genetic variation (80%) within populations was observed, emphasizing the potential for genetic improvement. Among the eight genotypes studied, LM and KAT were drought tolerant and genetically diverse and therefore could be used as parents for developing drought tolerance in pigeon pea. Full article
(This article belongs to the Section Plant Response to Abiotic Stress and Climate Change)
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<p>Unweighted pair group method of arithmetic mean (UPGMA) dendrogram based on Jaccard’s coefficient pigeon pea genotypes using SCoT markers. Genotypes: P1, P2, P3, SM, MM, LM, KAT, and P9.</p>
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<p>Principal coordinate analysis (PCoA) of the eight pigeon pea genotypes collected from Genebank of Kenya (Kitui and Machakos Counties) as revealed by the 20 SCoT markers.</p>
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18 pages, 7121 KiB  
Article
Trajectory Preview Tracking Control for Self-Balancing Intelligent Motorcycle Utilizing Front-Wheel Steering
by Fei Lai, Hewang Hu and Chaoqun Huang
Appl. Syst. Innov. 2024, 7(6), 115; https://doi.org/10.3390/asi7060115 (registering DOI) - 16 Nov 2024
Abstract
Known for their compact size, mobility, and off-road capabilities, motorcycles are increasingly used for logistics, emergency rescue, and reconnaissance. However, due to their two-wheeled nature, motorcycles are susceptible to instability, heightening the risk of tipping during cornering. This study includes some research and [...] Read more.
Known for their compact size, mobility, and off-road capabilities, motorcycles are increasingly used for logistics, emergency rescue, and reconnaissance. However, due to their two-wheeled nature, motorcycles are susceptible to instability, heightening the risk of tipping during cornering. This study includes some research and exploration into the following aspects: (1) The design of a front-wheel steering self-balancing controller. It achieves self-balance during motion by adjusting the front-wheel steering angle through manipulation of handlebar torque. (2) Trajectory tracking control based on preview control theory. It establishes a proportional relationship between lateral deviation and lean angle, as determined by path preview. The desired lean angle then serves as input for the self-balancing controller. (3) A pre-braking controller for enhanced active safety. To prevent lateral slide on wet and slippery surfaces, the controller is designed considering the motorcycle’s maximum braking deceleration. These advancements were validated via a joint BikeSim and Matlab/Simulink simulation, which included scenarios such as double lane changes and 60 m-radius turns. The results demonstrate that the intelligent motorcycle equipped with the proposed control algorithm tracks trajectories and maintains stability effectively. Full article
16 pages, 1020 KiB  
Article
Differential Dynamics and Roles of FKBP51 Isoforms and Their Implications for Targeted Therapies
by Silvia Martinelli, Kathrin Hafner, Maik Koedel, Janine Knauer-Arloth, Nils C. Gassen and Elisabeth B. Binder
Int. J. Mol. Sci. 2024, 25(22), 12318; https://doi.org/10.3390/ijms252212318 (registering DOI) - 16 Nov 2024
Abstract
The expression of FKBP5, and its resulting protein FKBP51, is strongly induced by glucocorticoids. Numerous studies have explored their involvement in a plethora of cellular processes and diseases. There is, however, a lack of knowledge on the role of the different RNA [...] Read more.
The expression of FKBP5, and its resulting protein FKBP51, is strongly induced by glucocorticoids. Numerous studies have explored their involvement in a plethora of cellular processes and diseases. There is, however, a lack of knowledge on the role of the different RNA splicing variants and the two protein isoforms, one missing functional C-terminal motifs. In this study, we use in vitro models (HeLa and Jurkat cells) as well as peripheral blood cells of a human cohort (N = 26 male healthy controls) to show that the two expressed variants are both dynamically upregulated following dexamethasone, with significantly earlier increases (starting 1–2 h after stimulation) in the short isoform both in vitro and in vivo. Protein degradation assays in vitro showed a reduced half-life (4 h vs. 8 h) of the shorter isoform. Only the shorter isoform showed a subnuclear cellular localization. The two isoforms also differed in their effects on known downstream cellular pathways, including glucocorticoid receptor function, macroautophagy, immune activation, and DNA methylation regulation. The results shed light on the difference between the two variants and highlight the importance of differential analyses in future studies with implications for targeted drug design. Full article
(This article belongs to the Section Biochemistry)
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<p>FKBP5/51 transcription variants and isoforms: (<b>a</b>) Schematic view of the <span class="html-italic">FKBP5</span> locus on human chromosome 6 and the four splicing variants of the gene (adapted from <a href="http://gtexportal.org" target="_blank">gtexportal.org</a>). (<b>b</b>) Schematic view of FKBP51 isoform 1 and 2 protein structures and 3D structure models generated with the Swiss model repository server of the expasy portal (<a href="http://swissmodel.expasy.org" target="_blank">swissmodel.expasy.org</a> (accessed on 16 October 2024); [<a href="#B23-ijms-25-12318" class="html-bibr">23</a>]). Domains are indicated in black and experimentally validated domain-associated binding partners in blue. (<b>c</b>) Transcription variant-specific <span class="html-italic">FKBP5</span> expression throughout human tissues (adapted from <a href="http://gtexportal.org" target="_blank">gtexportal.org</a>; [<a href="#B13-ijms-25-12318" class="html-bibr">13</a>]). The data used for the analyses described in this figure were obtained from: <a href="http://www.gtexportal.org" target="_blank">www.gtexportal.org</a>, the GTEx Portal on 14 September 2023. The terms and conditions for the use of data and images can be found here: <a href="https://www.gtexportal.org/home/downloads/adult-gtex/overview" target="_blank">https://www.gtexportal.org/home/downloads/adult-gtex/overview</a>, accessed on 14 September 2023.</p>
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<p>Expression of FKBP5 splicing variants in HeLa cells: (<b>a</b>) RT-qPCR quantification of FKBP51 variants in unstimulated HeLa cells. (<b>b</b>) RT-qPCR quantification of FKBP51 variants, expressed as fold change in Dex-treated over vehicle-treated, normalized on the housekeeper YWHAZ of HeLa cells treated with 100 nM Dex or vehicle for 24 h. Two-way ANOVA with Geisser–Greenhouse correction (shown in the box) and Sidak’s multiple comparisons test (shown in the graph). Data shown as mean ± SEM. (<b>c</b>) Fold change in FKBP5 variants 1 and 4 over vehicle and normalized over YWHAZ at 0, 1, 3, 6, and 23 h after Dex stimulation. Mixed effects model with Geisser–Greenhouse correction (shown in the box) and Sidak’s multiple comparisons test (shown in the graph). Data shown as box-and-whisker plot (Tukey style). (<b>d</b>) Pulse-chase assay of FKBP51 isoform 1 and 2 of HeLa cells transfected with HaloTag<sup>®</sup>-tagged-isoform 1 or HaloTag<sup>®</sup>-tagged-isoform 2, pulsed with a fluorophore, and chased for 2, 4, 8, and 16 h. Dotted line indicates half-life of the protein. Quantifications were made from Western blots. * <span class="html-italic">p</span> &lt; 0.05. Two-way ANOVA (shown in the box) and Sidak’s multiple comparisons test (shown in the graph). Data shown as mean ± SEM. For all statistics * <span class="html-italic">p</span> &lt; 0.05, ** <span class="html-italic">p</span> &lt; 0.01, **** <span class="html-italic">p</span> &lt; 0.0001, ns = not significant.</p>
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<p>Differential pathway regulation of FKBP51 isoforms: (<b>a</b>) Epifluorescent and bright field imaging of HeLa cells transfected with GFP-control vector, GFP-tagged FKBP51 isoform 1 or GFP-tagged FKBP51 isoform 2 24 h prior to imaging. (<b>b</b>,<b>c</b>) GRE-driven reporter gene assay performed in HeLa cells transfected with (<b>b</b>) FKBP51 isoform 1, FKBP51 isoform 2 or an empty vector (ctr vector), or (<b>c</b>) in WT (expressing both isoform), full KO and Isoform 1 KO (iso1 KO) HeLa cells treated with 0.1 nM, 0.3 nM, 1 nM, 3 nM, 10 nM, 30 nM, 100 nM, or vehicle for 4 h. Two-way ANOVA (shown in the box) with Tukey multiple comparisons test (shown in the graph). * indicates comparison with control/WT and isoform 1/full KO, # indicates comparison between isoform 1 and isoform 2, and <span>$</span> refers to comparison between WT and iso 1 KO. (** &amp; ## &amp; <span>$</span><span>$</span> <span class="html-italic">p</span> &lt; 0.01, *** &amp; ### <span class="html-italic">p</span> &lt; 0.0005, **** &amp; #### <span class="html-italic">p</span> &lt; 0.0001, ns = not significant). (<b>d</b>) Representative Western blots for different pathway markers performed on lysates from HeLa cells transfected with FKBP51 isoform 1, FKBP51 isoform 2 or an empty vector (<b>e</b>–<b>j</b>) Quantification of Western blots analyses displayed in (<b>d</b>): (<b>e</b>) phosphorylated AKT (pAKT) normalized on total AKT, (<b>f</b>–<b>h</b>) autophagy markers, BECN1, ATG12 and LC3B-II/I; (<b>i</b>) phosphorylated DNMT (pDNMT) normalized on total DNMT; (<b>j</b>) phosphorylated NFAT (pNFAT) normalized on total NFAT from Jurkat cells transfected with FKBP51 isoform 1, FKBP51 isoform 2 or an empty vector; * <span class="html-italic">p</span> &lt; 0.05, ** <span class="html-italic">p</span> &lt; 0.01, *** <span class="html-italic">p</span> &lt; 0.0005, ns = not significant. Mann–Whitney test. Data shown as mean ± SEM.</p>
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