Search Results (480)

Autophagy plays a crucial role in hepatic lipid metabolism, making it a key therapeutic target for addressing metabolic dysfunction-associated steatotic liver disease (MASLD). This study evaluates the efficacy of the Tat-Beclin-1 (TB-1) peptide, a specific autophagy inducer, in mitigating MASLD. Initially, we examined the impact of the TB-1 peptide on autophagic activity and intracellular lipid metabolism in HepG2 cells treated with oleic acid, using a Tat scrambled (TS) control peptide for comparison. Subsequently, we established a MASLD mouse model by feeding a high-fat diet (HFD) for 16 weeks, followed by intraperitoneal administration of TB-1 or TS. Assessments included liver histopathology, serum biochemistry, and autophagy marker analysis. Our findings indicate that the TB-1 peptide significantly increased the LC3II/β-actin ratio in a dose- and time-dependent manner while promoting the expression of key autophagy markers Beclin-1 and ATG5-12. Furthermore, TB-1 treatment led to a marked reduction in both the size and number of lipid droplets in HepG2 cells. In vivo, HFD-fed mice exhibited increased liver weight, elevated serum alanine aminotransferase levels, and impaired oral glucose tolerance. TB-1 administration effectively mitigated these hepatic and metabolic disturbances. Histological analysis further revealed a substantial reduction in the severity of hepatic steatosis and fibrosis in TB-1-treated mice compared to TS controls. In conclusion, the TB-1 peptide shows significant potential in reducing the severity of MASLD in both HepG2 cell models and HFD-induced MASLD mouse models. Enhancing autophagy through TB-1 represents a promising therapeutic strategy for treating MASLD. Full article

Cadmium (Cd) exposure can induce follicular atresia and laying performance reduction in hens, which is linked to autophagy within the granulosa cells. Selenium (Se) can influence autophagy and counteract Cd toxicity. This study aimed to investigate the protective effect of Se on Cd-induced follicular atresia in laying hens. Sixty-four laying hens were randomly allocated into 4 treatments: control group: basal diet; Se group: basal diet + 0.4 mg/kg Se from selenized yeast; Cd group: basal diet + 25 mg/kg Cd from CdCl₂; and Cd+Se group: basal diet + 25 mg/kg Cd + 0.4 mg/kg Se. Compared to the Cd group, Se supplementation alleviated the ovarian pathological changes and oxidative stress in the follicles, serum, liver, and ovary, increased daily laying production, ovarian weight and F5–F1 follicle amounts, serum levels of progesterone and oestradiol, and up-regulated mTOR expression (p < 0.05), while decreasing the count of autophagic vacuoles, ovarian atresia follicle numbers, and Cd deposition, and down-regulated expression levels of autophagy-related mRNAs, including ATG5, LC3-I, and LC3-II, Beclin1, and Dynein in the follicles (p < 0.05). In conclusion, 0.4 mg/kg Se supplementation protected against Cd-induced laying performance reduction and follicular atresia, which were achieved via decreasing oxidative stress and inhibiting mTOR pathways of autophagy. Full article

Excessive exposure to manganese (Mn) increases the risk of chronic neurological diseases, including Parkinson’s disease (PD) and other related Parkinsonisms. Aggregated α-synuclein (αSyn), a hallmark of PD, can spread to neighboring cells by exosomal release from neurons. We previously discovered that Mn enhances its spread, triggering neuroinflammatory and neurodegenerative processes. To better understand the Mn-induced release of exosomal αSyn, we examined the effect of Mn on endosomal trafficking and misfolded protein degradation. Exposing MN9D dopaminergic neuronal cells stably expressing human wild-type (WT) αSyn to 300 μM Mn for 24 h significantly suppressed protein and mRNA expression of Rab11a, thereby downregulating endosomal recycling, forcing late endosomes to mature into multivesicular bodies (MVBs). Ectopic expression of WT Rab11a significantly mitigated exosome release, whereas ectopic mutant Rab11a (S25N) increased it. Our in vitro and in vivo studies reveal that Mn exposure upregulated (1) mRNA and protein levels of endosomal Rab27a, which mediates the fusion of MVBs with the plasma membrane; and (2) expression of the autophagosomal markers Beclin-1 and p62, but downregulated the lysosomal marker LAMP2, thereby impairing autophagolysosome formation as confirmed by LysoTracker, cathepsin, and acridine orange assays. Our novel findings demonstrate that Mn promotes the exosomal release of misfolded αSyn by impairing endosomal trafficking and protein degradation. Full article

This study explores the neuroprotective effects of resveratrol (Resv) against tri-o-cresyl phosphate (TOCP)-induced neurotoxicity in the spinal cord of adult hens. It is well documented that TOCP exposure causes significant neurodegeneration via mechanisms that involve endoplasmic reticulum (ER) stress and impaired autophagy. In this experiment, adult hens were assigned to one of four groups: Control, Resv, TOCP, and TOCP + Resv. The spinal cord tissues were examined through transmission electron microscopy, hematoxylin and eosin (HE) staining, Nissl staining, and Western blotting to evaluate key proteins associated with ER stress and autophagy. Additionally, RT-qPCR and immunofluorescence were employed to measure sirtuin1 (SIRT1) expression. The findings revealed that TOCP induced severe ultrastructural damage, including disrupted myelin sheaths, dilated ER, and extensive neurodegeneration, as confirmed by histological evaluations. The expression levels of GRP78, p-PERK, p-eIF2α, ATF4, CHOP, Beclin-1, P62, and LC3-II were also significantly elevated by TOCP. However, Resv treatment markedly attenuated these pathological changes by reducing ER stress, restoring autophagic flux, and upregulating SIRT1 expression, preserving spinal cord integrity. These results indicate that Resv can effectively counteract TOCP-induced neurotoxicity by modulating ER stress and autophagy, underscoring its potential as a therapeutic agent for neuroprotection. Full article

Endocannabinoids have attracted great interest for their ability to counteract the neuroinflammation underlying Alzheimer’s disease (AD). Our study aimed at evaluating whether this activity was also due to a rebalance of autophagic mechanisms in cellular and animal models of AD. We supplied URB597, an inhibitor of Fatty-Acid Amide Hydrolase (FAAH), the degradation enzyme of anandamide, to microglial cultures treated with Aβ_25-35, and to Tg2576 transgenic mice, thus increasing the endocannabinoid tone. The addition of URB597 did not alter cell viability and induced microglia polarization toward an anti-inflammatory phenotype, as shown by the modulation of pro- and anti-inflammatory cytokines, as well as M1 and M2 markers; moreover microglia, after URB597 treatment released higher levels of Bdnf and Nrf2, confirming the protective role underlying endocannabinoids increase, as shown by RT-PCR and immunofluorescence experiments. We assessed the number and area of amyloid plaques in animals administered with URB597 compared to untreated animals and the expression of autophagy key markers in the hippocampus and prefrontal cortex from both groups of mice, via immunohistochemistry and ELISA. After URB597 supply, we detected a reduction in the number and areas of amyloid plaques, as detected by Congo Red staining and a reshaping of microglia activation as shown by M1 and M2 markers’ modulation. URB597 administration restored autophagy in Tg2576 mice via an increase in BECN1 (Beclin1), ATG7 (Autophagy Related 7), LC3 (light chain 3) and SQSTM1/p62 (sequestrome 1) as well as via the activation of the ULK1 (Unc-51 Like Autophagy Activating Kinase 1) signaling pathway, suggesting that it targets mTOR/ULK1-dependent autophagy pathway. The potential of endocannabinoids to rebalance autophagy machinery may be considered as a new perspective for therapeutic intervention in AD. Full article

Metabolic dysfunction-associated fatty liver disease (MASLD) is a widespread liver disorder characterized by excessive fat accumulation in the liver, commonly associated with metabolic syndrome components such as obesity, diabetes, and dyslipidemia. With a global prevalence of up to 30%, MASLD is projected to affect over 100 million people in the U.S. and 20 million in Europe by 2030. The disease ranges from Steatotic Lived Disease (SLD) to more severe forms like metabolic dysfunction-associated steatohepatitis (MASH), which can progress to cirrhosis and hepatocellular carcinoma. Autophagy, a cellular process crucial for lipid metabolism and homeostasis, is often impaired in MASLD, leading to increased hepatic lipid accumulation and inflammation. Key autophagy-related proteins, such as Beclin1, LC3A, SQSTM1 (p62), CD36, and Perilipin 3, play significant roles in regulating this process. Disruption in these proteins contributes to the pathogenesis of MASLD. Quercetin, a natural polyphenolic flavonoid with antioxidant and anti-inflammatory properties, has promising results in mitigating MASLD. It may reduce hepatic lipid accumulation, improve mitochondrial function, and enhance autophagy. However, further research is needed to elucidate its mechanisms and validate its therapeutic potential in clinical settings. This underscores the need for continued investigation into autophagy and novel treatments for MASLD. Full article

The present study aims to evaluate the effect of a dietary supplementation with 10% grape pomace (GP) on the whole blood transcriptome of lactating ewes. By applying a log₂FC higher than 0.5 or lower than −0.5 and a false discovery rate (FDR) <0.05, the down-regulation of genes coding for plexin C1, ethanolamine kinase 1, tax1-binding protein 1, transmembrane 9 superfamily member 2, and Beclin-1 was observed in animals that received the dietary supplementation. This aspect was also accompanied by a reduction in the blood activity of matrix metalloproteinase 9 (MMP-9; p < 0.05), a gelatinase commonly involved in both acute and chronic pathological events. The ELISA test on other factors involved in inflammatory processes, interleukin 1 (IL-1) and tumor necrosis factor α (TNF-α), as well as in the antioxidant response, glutathione peroxidase (GPx), and catalase (CAT), did not reveal any significant changes (p > 0.05). Overall, the introduction of GP in the diet of ewes gave indications of greater efficacy in preserving animal welfare, with interesting cues regarding the valorization of a by-product with a high biological value. Full article

Heat shock protein 90 (HSP90) is recognized for its protective effects against heat stress damage; however, the specific functions and underlying molecular mechanisms of HSP90 in heat-stressed cardiomyocytes remain largely unexplored, particularly in tropical species. In our study, Wenchang chickens (WCCs) were classified into two groups: the heat stress survival (HSS) group and the heat stress death (HSD) group, based on their survival following exposure to heat stress. Heat stress resulted in significant cardiomyocyte damage, mitochondrial dysfunction, and apoptosis in the HSD group, while the damage was less pronounced in the HSS group. We further validated these findings in primary cardiomyocytes derived from Wenchang chickens (PCWs). Additionally, heat stress was found to upregulate Pink1/Parkin-mediated mitophagy, which was accompanied by an increase in HSP90 expression in both cardiomyocytes and PCWs. Our results demonstrated that HSP90 overexpression enhances PINK1/Parkin-mediated mitophagy, ultimately inhibiting apoptosis and oxidative stress in heat-stressed PCWs. However, the application of Geldanamycin (GA) reversed these effects. Notably, we discovered that HSP90 interacts with Beclin-1 through mitochondrial translocation and directly regulates mitophagy levels in PCWs. In summary, we have elucidated a novel role for HSP90 and mitophagy in regulating heat stress-induced acute cardiomyocyte injury. Full article

Skin inflammation, characterized by redness, swelling, and discomfort, is exacerbated by oxidative stress, where compounds like 7-methylsulfonylheptyl isothiocyanate (7-MSI) from cruciferous plants exhibit promising antioxidant and anti-inflammatory properties, though their effects on skin aging and underlying mechanisms involving the NLRP3 inflammasome and autophagy are not fully elucidated. NLRP3 is a crucial inflammasome involved in regulating inflammatory responses, and our study addresses its activation and associated physiological effects. Using biochemical assays such as ELISA, RT-qPCR, Western blotting, confocal microscopy, and RNA interference, we evaluated 7-MSI’s impact on cytokine production, protein expression, and genetic regulation in Raw 264.7 and RAW-ASC cells. 7-MSI significantly reduced TNF-α, IL-1β, IL-6, COX-2, and PGE transcription levels in LPS-stimulated Raw 264.7 cells, indicating potent anti-inflammatory effects. It also inhibited NF-κB signaling and NLRP3 inflammasome activity, demonstrating its role in preventing the nuclear translocation of NF-κB and reducing caspase-1 and IL-1β production. In terms of autophagy, 7-MSI enhanced the expression of Beclin-1, LC3, and Atg12 while reducing phospho-mTOR levels, suggesting an activation of autophagy. Moreover, it effectively decreased ROS production induced by LPS. The interaction between autophagy and inflammasome regulation was further confirmed through experiments showing that interference with autophagy-related genes altered the effects of 7-MSI on cytokine production. Collectively, this study demonstrates that 7-MSI promotes autophagy, including ROS removal, and to suppress inflammation, we suggest the potential use of 7-MSI as a skin care and disease treatment agent. Full article

HIV-associated cardiovascular diseases remain a leading cause of death in people living with HIV/AIDS (PLWHA). Although antiretroviral drugs suppress the viral load, they fail to remove the virus entirely. HIV-1 Nef protein is known to play a role in viral virulence and HIV latency. Expression of Nef protein can be detected in different organs, including cardiac tissue. Despite the established role of Nef protein in HIV-1 replication, its impact on organ function inside the human body is not clear. To understand the effect of Nef at the organ level, we created a new Nef-transgenic (Nef-TG) mouse that expresses Nef protein in the heart. Our study found that Nef expression caused inhibition of cardiac function and pathological changes in the heart with increased fibrosis, leading to heart failure and early mortality. Further, we found that cellular autophagy is significantly inhibited in the cardiac tissue of Nef-TG mice. Mechanistically, we found that Nef protein causes the accumulation of Bcl2 and Beclin-1 proteins in the tissue, which may affect the cellular autophagy system. Additionally, we found Nef expression causes upregulation of the cellular senescence marker p21 and senescence-associated β-galactosidase expression. Our findings suggest that the Nef-mediated inhibition of autophagy and induction of senescence markers may promote aging in PLWHA. Our mouse model could help us to understand the effect of Nef protein on organ function during latent HIV infection. Full article

Background/Objectives: Acute kidney injury (AKI) syndrome is distinguished by a quick decline in renal excretory capacity and usually diagnosed by the presence of elevated nitrogen metabolism end products and/or diminished urine output. AKI frequently occurs in hospital patients, and there are no existing specific treatments available to diminish its occurrence or expedite recovery. For an extended period in the food industry, Pediococcus acidilactici has been distinguished by its robust bacteriocin production, effectively inhibiting pathogen growth during fermentation and storage. Methods: In this study, the aim is to assess the effectiveness of P. acidilactici GKA4, dead probiotic GKA4, and postbiotic GKA4 against cisplatin-induced AKI in an animal model. The experimental protocol involves a ten-day oral administration of GKA4, dead probiotic GKA4, and postbiotic GKA4 to mice, with a cisplatin intraperitoneal injection being given on the seventh day to induce AKI. Results: The findings indicated the significant alleviation of the renal histopathological changes and serum biomarkers of GKA4, dead probiotic GKA4, and postbiotic GKA4 in cisplatin-induced nephrotoxicity. GKA4, dead probiotic GKA4, and postbiotic GKA4 elevated the expression levels of HO-1 and decreased the expression levels of Nrf-2 proteins. In addition, the administration of GKA4, dead probiotic GKA4, and postbiotic GKA4 significantly reduced the expression of apoptosis-related proteins (Bax, Bcl-2, and caspase 3), autophagy-related proteins (LC3B, p62, and Beclin1), and endoplasmic reticulum (ER) stress-related proteins (GRP78, PERK, ATF-6, IRE1, CHOP, and Caspase 12) in kidney tissues. Notably, GKA4, dead probiotic GKA4, and postbiotic GKA4 also upregulated the levels of proteins related to organic anion transporters and organic cation transporters. Conclusions: Overall, the potential therapeutic benefits of GKA4, dead probiotic GKA4, and postbiotic GKA4 are significant, particularly after cisplatin treatment. This is achieved by modulating apoptosis, autophagy, ER stress, and transporter proteins to alleviate oxidative stress. Full article

Background/Objectives: Homocysteine (Hcy) and iron are factors co-related with the progression of cardiovascular diseases. The vascular endothelium is an important barrier for physiological homeostasis, and its impairment initiates cardiovascular injury. However, the mechanism underlying Hcy-caused vascular endothelial cell injury and the participation of iron are not fully elucidated. This study aims to investigate the Hcy-induced vascular endothelial injury and iron metabolism dysfunction as well as the underlying molecular mechanism. Methods: Human umbilical vein endothelial cells (HUVECs) were employed as the experimental model to examine the Hcy-induced endothelial injury and its underlying mechanism via various biochemical assays. Results: Hcy suppressed the cell viability and proliferation and caused cell death in a concentration-dependent manner. Hcy induced cell cycle arrest, apoptosis, and autophagy as well as impairment of intracellular energy metabolism. Hcy disrupted the intracellular antioxidant system and mitochondrial function by increasing intracellular ROS, MDA and mitochondrial content, and decreasing the SOD activity and mitochondrial membrane potential. Hcy significantly reduced the GSH-Px activity along with the accumulation of intracellular GSH in a concentration-dependent manner. Ferroptosis inhibitors, Ferrostatin-1 (Fer-1), and Deferoxamine (DFO) significantly decreased the Hcy-caused cytotoxicity accompanied by a reduction in dysregulated mitochondria content, but only DFO ameliorated the elevation of intracellular ROS, and neither Fer-1 nor DFO affected the Hcy-caused reduction in intracellular ATP. In addition, Hcy decreased the intracellular concentration of iron, and supplementing Hcy with various concentrations of Fe³⁺ increased the cell viability and decreased the LDH release in a concentration-dependent manner. Hcy dramatically decreased the mRNA expression level of transferrin receptor while increasing the mRNA expression levels of transferrin, ferritin light chain, ferritin heavy chain, ferroportin, and SLC7A11. Moreover, Hcy suppressed the protein expression of phospho-Akt, phospho-mTOR, Beclin-1, LC3A/B, Nrf2, HO-1, phospho-MEK1/2, phospho-ERK1/2, and Caspase-3 in concentration- and time-dependent manners. Conclusions: Hcy-induced vascular endothelial injury is likely to be associated with apoptosis and autophagy, but not ferroptosis. The key underlying mechanisms are involved in the disruption of the intracellular antioxidant system and iron metabolism via regulation of PI3K/Akt/mTOR, MAPKs, Nrf2/HO-1, and iron metabolism. Full article

Background/Objectives: Autism spectrum disorder (ASD) is a neurodevelopmental condition marked by social interaction difficulties, repetitive behaviors, and immune dysregulation with elevated pro-inflammatory markers. Autophagic deficiency also contributes to social behavior deficits in ASD. Histamine H3 receptor (H3R) antagonism is a potential treatment strategy for brain disorders with features overlapping ASD, such as schizophrenia and Alzheimer’s disease. Methods: This study investigated the effects of sub-chronic systemic treatment with the H3R antagonist E159 on social deficits, repetitive behaviors, neuroinflammation, and autophagic disruption in male BTBR mice. Results: E159 (2.5, 5, and 10 mg/kg, i.p.) improved stereotypic repetitive behavior by reducing self-grooming time and enhancing spontaneous alternation in addition to attenuating social deficits. It also decreased pro-inflammatory cytokines in the cerebellum and hippocampus of treated BTBR mice. In BTBR mice, reduced expression of autophagy-related proteins LC3A/B and Beclin 1 was observed, which was elevated following treatment with E159, attenuating the disruption in autophagy. The co-administration with the H3R agonist MHA (10 mg/kg, i.p.) reversed these effects, highlighting the role of histaminergic neurotransmission in observed behavioral improvements. Conclusions: These preliminary findings suggest the therapeutic potential of H3R antagonists in targeting neuroinflammation and autophagic disruption to improve ASD-like behaviors. Full article

The role of autophagy goes far beyond the elimination of damaged cellular components and the quality control of proteins. It also cleanses cells from inclusions, including pathogenic viruses, and provides energy-forming components. The liver, which is an organ with increased metabolism, is made up of cells that are particularly vulnerable to damage. Therefore, detoxification of liver cells in the process of autophagy has become a very important issue clinically. The aim of this study was an immunohistochemical evaluation of proteins activated in rat liver cells at different stages of hyperbaric autophagy. The rats used for the study were randomly divided into six equivalent groups—three control groups and three experimental groups. Animals from the experimental groups were subjected to hyperbaric treatment in a hyperbaric chamber, with a pressure of 1.6 ATA for 120 min. They breathed atmospheric air. Rats were decapitated within 5 or 10 days after removal from the chamber. Immunohistochemical reactions with beclin 1, LC3B, RAB7, and HSC73 proteins were carried out on preparations made from liver slices. A three-step labeled streptavidin–biotin detection method of paraffin blocks (LSAB three-step) was used for immunohistochemical research. The results were evaluated using computer programs for morphometric analysis of microscopic images by calculating the mean surface areas occupied by a positive immunohistochemical reaction in individual groups for all antibodies tested. Increased closure of substrates in the autophagosome (beclin 1) induced late endosome transport and accelerated autophagosome maturation process (RAB7). Furthermore, a larger number of autophagosomes (LC3B) was observed in liver cells immediately after the cessation of hyperbaric activity; however, this decreased after 5 days. During this time, chaperone-mediated autophagy (HSC73) was observed on a larger scale. This means that increased macroautophagy induced by hyperbaric treatment weakens with time that has elapsed since the cessation of high pressure, whereas similarly induced chaperone-mediated autophagy intensifies over time. Full article

Oxidative stress triggered by testicular torsion and detorsion in young males could negatively impact future fertility. Using a rat animal model for testicular IRI (tIRI), we aim to study the induction of autophagy (ATG) during testicular ischemia and tIRI and the role of oxidative-stress-induced c-Jun N-terminal Kinase (JNK) as a cytoprotective mechanism. Sixty male Sprague-Dawley rats were divided into five groups: sham, ischemia only, ischemia+SP600125 (a JNK inhibitor), tIRI only, and tIRI+SP600125. The tIRI rats underwent an ischemic injury for 1 h followed by 4 h of reperfusion, while ischemic rats were subjected to 1 h of ischemia only without reperfusion. Testicular-ischemia-induced Beclin 1 and LC3B expression was associated with decreased p62/SQSTM1 expression, increased ATP and alkaline phosphatase (AP) activity, and slightly impaired spermatogenesis. SP600125 treatment improved p62 expression and reduced the levels of Beclin 1 and LC3B but did not affect ATP or AP levels. The tIRI-induced apoptosis lowered the expression of the three ATG proteins and AP activity, activated caspase 3, and caused spermatogenic arrest. SP600125-inhibited JNK during tIRI restored sham levels to all investigated parameters. This study emphasizes the regulatory role of JNK in balancing autophagy and apoptosis during testicular oxidative injuries. Full article