Effect Of Apoptosis Research Articles

Multipotent Effect of Clozapine on Lipopolysaccharide-Induced Acetylcholinesterase, Cyclooxygenase-2,5-Lipoxygenase, and Caspase-3: In Vivo and Molecular Modeling Studies

Dual inhibition of cyclooxygenase-2 (COX-2) and lipoxygenase (LOX) is a recognized strategy for enhanced anti-inflammatory effects in small molecules, offering potential therapeutic benefits for individuals at risk of dementia, particularly those with neurodegenerative diseases, common cancers, and diabetes type. Alzheimer’s disease (AD) is the most common cause of dementia, and the inhibition of acetylcholinesterase (AChE) is a key approach in treating AD. Meanwhile, Caspase-3 catalyzes early events in apoptosis, contributing to neurodegeneration and subsequently AD. Structure-based virtual screening of US-FDA-approved molecules from the ZINC15 database identified clozapine (CLOZ) as the dual inhibitor of COX-2 and AChE, with significant binding affinity. Further molecular docking of CLOZ in the active site of LOX and Caspase-3 also showed significant binding potential. Further, the results from molecular docking were validated using molecular dynamics simulation (MDS) studies, confirming the results from molecular docking. The results from MDS showed good binding potential and interactions with key residues. The CLOZ was further assessed using lipopolysaccharide (LPS)-challenged rats treated for thirty days at doses of 5 and 10 mg/kg, p.o. The results demonstrated modulation of COX-2, 5-LOX, AChE, Caspase-3, and MDA in LPS-induced brains. Additionally, the expression level of IL-10 was also measured. Our results showed a significant decrease in the levels of COX-2, 5-LOX, AChE, Caspase-3, and MDA. Our results also showed a significant decrement in the pro-inflammatory markers NF-κB, TNF-α, and IL-6 and an improvement in the levels of anti-inflammatory markers IL-10 and TGF-β1. Overall, the findings indicate that CLOZ has potential for neuroprotective effects against LPS-treated rats and can be explored.

Microplastics and nanoplastics: emerging threats to cardiovascular health – a comprehensive review

Background: Global plastic production surged to 400.3 million metric tons in 2022, contributing significantly to environmental pollution. Projections estimate that 13.2 billion tons of plastic waste will be present in ecosystems by 2050. This increase in plastic production has led to substantial human exposure to microplastics (MPs) and nanoplastics (NPs). While their environmental and general health impacts are well-documented, the specific effects on cardiovascular health remain underexplored. Objectives: This review aims to examine the presence of MPs and NPs in the environment, their routes of human exposure, and their toxicological implications for the cardiovascular system (CVS), focusing on oxidative stress, apoptosis, cardiac fibrosis, and major adverse cardiovascular events (MACE). Methods: A comprehensive literature review was conducted using PubMed, Scopus, and Google Scholar. Relevant studies from the past 10 years were selected based on keywords like “microplastics,” “nanoplastics,” and “cardiovascular health.” Results: MPs and NPs are found in air, water, and food, entering the human body primarily through inhalation, ingestion, and dermal contact. These particles induce oxidative stress, mitochondrial dysfunction, and apoptosis, which impair cardiovascular health. MPs have been detected in arterial tissues, particularly in atherosclerotic plaques, correlating with increased MACE risk. MP exposure is linked to VC, reduced vessel flexibility, and increased thrombosis severity. Additionally, MPs contribute to inflammation and lipid metabolism disruption, which further exacerbate heart disease. Conclusion: The evidence suggests a concerning link between plastic exposure and cardiovascular health, highlighting the urgent need for further research to understand the long-term effects of MPs and NPs on CVSs.

Role of programmed cell death in mammalian ovarian follicular atresia.

Programmed cell death (PCD) is a fundamental process in the development process of organisms, including apoptosis, autophagy, ferroptosis, and pyroptosis. In mammalian ovaries, 99 % of follicles undergo atresia, while only 1 % mature and ovulate, which limits the reproductive efficiency of mammals. The PCD process is closely related to the regulation of follicle development and atresia. Recently, an increasing number of studies have reported that autophagy, pyroptosis, and ferroptosis of PCD are involved in regulating granulosa cell apoptosis and follicular atresia. Granulosa cell apoptosis is a hallmark of follicular atresia. Therefore, an understanding of molecular mechanisms regulating PCD events is required for future advances in the diagnosis and management of various disorders of follicular atresia. This review summarizes recent work on apoptosis, autophagy, pyroptosis, and ferroptosis of PCD that affect granulosa cell survival and follicular atresia, and further elucidating the mechanisms of follicular atresia and providing new directions for improving the reproductive capacity of humans and animals.

Permeability-Controlled Probe for Ratiometric Detection of Plasma Membrane Integrity and Late Apoptosis.

The destruction of plasma membrane integrity is closely related to immune response, neuronal injury, cell apoptosis, and other pathological events. However, the construction of ratiometric fluorescent probes capable of detecting plasma membrane integrity remains a significant challenge, hindering in-depth studies on related biomedical areas. Herein, a polarity-responsive fluorescent probe was constructed for the ratiometric detection of cell membrane integrity for the first time. The probe targeted intact plasma membranes in healthy cells and relocated into the cytoplasm to give significantly red-shifted fluorescence after plasma membrane damage. Molecular simulations revealed that the high transmembrane barrier and amphipathic nature of the probe were responsible for its targeting ability. With the probe, the ratiometric detection of late apoptosis stage was realized for the first time, and the membrane damage of tumor cells induced by UV irradiation, toxins, and antitumor drugs was visualized. The effect of formaldehyde on membrane integrity was evaluated using a probe, and cysteine was proved to be a potential detoxifier to counteract the toxicity of formaldehyde.

Reduction of endocytosis and EGFR signaling is associated with the switch from isolated to clustered apoptosis during epithelial tissue remodeling in Drosophila.

Epithelial tissues undergo cell turnover both during development and for homeostatic maintenance. Removal of cells is coordinated with the increase in number of newly dividing cells to maintain barrier function of the tissue. In Drosophila metamorphosis, larval epidermal cells (LECs) are replaced by adult precursor cells called histoblasts. Removal of LECs must counterbalance the exponentially increasing adult histoblasts. Previous work showed that the LEC removal accelerates as endocytic activity decreases throughout all LECs. Here, we show that the acceleration is accompanied by a mode switching from isolated single-cell apoptosis to clustered ones induced by the endocytic activity reduction. We identify the epidermal growth factor receptor (EGFR) pathway via extracellular-signal regulated kinase (ERK) activity as the main components downstream of endocytic activity in LECs. The reduced ERK activity, caused by the decrease in endocytic activity, is responsible for the apoptotic mode switching. Initially, ERK is transiently activated in normal LECs surrounding a single apoptotic LEC in a ligand-dependent manner, preventing clustered cell death. Following the reduction of endocytic activity, LEC apoptosis events do not provoke these transient ERK up-regulations, resulting in the acceleration of the cell elimination rate by frequent clustered apoptosis. These findings contrasted with the common perspective that clustered apoptosis is disadvantageous. Instead, switching to clustered apoptosis is required to accommodate the growth of neighboring tissues.

Gene, Protein, and in Silico Analyses of FoxO, an Evolutionary Conserved Transcription Factor in the Sea Urchin Paracentrotus lividus.

FoxO is a member of the evolutionary conserved family of transcription factors containing a Forkhead box, involved in many signaling pathways of physiological and pathological processes. In mammals, mutations or dysfunctions of the FoxO gene have been implicated in diverse diseases. FoxO homologs have been found in some invertebrates, including echinoderms. We have isolated the FoxO cDNA from the sea urchin Paracentrotus lividus (Pl-foxo) and characterized the corresponding gene and mRNA. In silico studies showed that secondary and tertiary structures of Pl-foxo protein corresponded to the vertebrate FoxO3 isoform, with highly conserved regions, especially in the DNA-binding domain. A phylogenetic analysis compared the Pl-foxo deduced protein with proteins from different animal species and confirmed its evolutionary conservation between vertebrates and invertebrates. The increased expression of Pl-foxo mRNA following the inhibition of the PI3K signaling pathway paralleled the upregulation of Pl-foxo target genes involved in apoptosis or cell-cycle arrest events (BI-1, Bax, MnSod). In silico studies comparing molecular data from sea urchins and other organisms predicted a network of Pl-foxo protein-protein interactions, as well as identified potential miRNAs involved in Pl-foxo gene regulation. Our data may provide new perspectives on the knowledge of the signaling pathways underlying sea urchin development.

A Golgi-targeted fluorescent probe for monitoring polarity dynamic during programmed cell death

Programmed cell death (PCD) is a controlled form of cell death and it plays an essential role in maintaining homeostasis. Golgi apparatus works as the hotspot during the early event of PCD and Golgi polarity, a vital microenvironment factor, can be regarded as an indicator of physiological status. Combined Golgi-targeted group phenylsulfonamide as electron acceptor group and triphenylamine as electron donor group, a novel Golgi-targeted fluorescent probe GTO had been developed. GTO showed good sensitivity and selectivity to polarity and its remarkable photostability makes it potentially useful for long-term cellular monitoring. In practice, GTO demonstrated good cell permeability and Golgi targeting capabilities. According to our results, GTO was applied to reveal the polarity increase during the early event of PCD and the encouraging results illustrated that GTO was an imaging tool for monitoring polarity in Golgi apparatus and the exploration in early diagnosis and drug discovery.

Female Sex Protects Cerebral Arteries from Mitochondrial Membrane Potential Depolarization and Cell Death Induced by Reactive Oxygen Species

Stroke and traumatic brain injury augment the production of reactive oxygen species (ROS) leading to apoptosis in cerebral arteries, and females are more resilient to vascular damage than males. Depolarization of mitochondrial membrane potential (ΔΨm) is a key event in apoptosis, however, when ΔΨm is suffciently depolarized, ATP synthase can reverse directions and act as a proton pump to limit ΔΨm depolarization. We hypothesized that ATP synthase attenuates depolarization of ΔΨm in cerebral arteries during acute oxidative stress thus limiting cell death. Posterior cerebral arteries (PCA; ~80 μm diameter) from male and female mice (age, 4-6 mo) were isolated, cannulated, and pressurized to 90 cm H2O at 36°C. Cell death was quantified with Hoechst 33342 (1 μM, labels all nuclei) and propidium iodide (2 μM, labels dead nuclei), and ΔΨm was evaluated with tetramethylrhodamine methyl ester (TMRM, 10 nM). Vessels were exposed to H2O2 (200 μM) in the presence/absence of ATP synthase inhibitor oligomycin (2 μM). H2O2 exposure (50 min) led to significantly (p<0.05) greater smooth muscle cell death in males compared to females (30±7.4% vs. 7±3%; n=8); there was a similar trend for endothelial cell death. Oligomycin greatly augmented apoptosis in PCAs from both males and females to ~80% and eliminated differences between sexes. Consistently, H2O2 evoked a more robust depolarization of ΔΨm in males vs. females and oligomycin enhanced ΔΨm depolarization to H2O2 leading to a similar response in both sexes. To directly depolarize ΔΨm, PCAs were treated with the protonophore FCCP (10 μM). Surprisingly, depolarization of ΔΨm to FCCP was greater in males vs. females, and oligomycin augmented depolarization and eliminated differences between sexes. FCCP initiated minimal (<5%) cell death at 50-min or 3-h exposure; oligomycin did not alter cell death to FCCP. We conclude that: 1) cerebral vessels from female mice possess greater resilience to H2O2 -induced apoptosis than males by limiting depolarization of ΔΨm; and 2) oxidative stress triggers cell death through pathways in addition to ΔΨm depolarization. Support: NIH R01NS134690. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Tissue-specific differences in Ca2+ sensitivity of the mitochondrial permeability transition pore (PTP). Experiments in male rat liver and heart.

Permeability transition pore (PTP) opening dissipates ion and electron gradients across the internal mitochondrial membrane (IMM), including excess Ca2+ in the mitochondrial matrix. After opening, immediate PTP closure must follow to prevent outer membrane disruption, loss of cytochrome c, and eventual apoptosis. Flickering, defined as the rapid alternative opening/closing of PTP, has been reported in heart, which undergoes frequent, large variations in Ca2+. In contrast, in tissues that undergo depolarization events less often, such as the liver, PTP would not need to be as dynamic and thus these tissues would not be as resistant to stress. To evaluate this idea, it was decided to follow the reversibility of the permeability transition (PT) in isolated murine mitochondria from two different tissues: the very dynamic heart, and the liver, which suffers depolarizations less frequently. It was observed that in heart mitochondria PT remained reversible for longer periods and at higher Ca2+ loads than in liver mitochondria. In all cases, Ca2+ uptake was inhibited by ruthenium red and PT was delayed by Cyclosporine A. Characterization of this phenomenon included measuring the rate of oxygen consumption, organelle swelling and Ca2+ uptake and retention. Results strongly suggest that there are tissue-specific differences in PTP physiology, as it resists many more Ca2+ additions before opening in a highly active organ such as the heart than in an organ that seldom suffers Ca2+ loading, such as the liver.

THE CURRENT STATE OF STEM CELL THERAPY FOR SPINAL CORD INJURY AND OTHER SYSTEMIC INJURIES

The pathomechanism of many diseases affecting the human brain and spinal cord has not been fully elucidated. Some organs of the human body have the ability to rebuild and regenerate in the event of apoptosis or necrosis of some cells. An organ with a high self-regeneration capacity is, for example, the liver. In this respect, the human nervous system is its opposite. This is related to the strict functional specialization of neurons and the fact that the function of the nervous system is influenced not only by the operation of individual cells, but also by efficient transmission in often huge and complex networks of neuronal connections, the damage of which is practically impossible to repair. This limited regenerative capacity is why cell loss and nerve fiber disruption are irreversible losses. This constitutes a significant problem in the treatment of patients with spinal cord injuries or suffering from diseases involving rapid (stroke) or constantly progressive (neurodegenerative diseases) loss of nerve cells. The aim of this work: This work presents the current and most interesting directions of research on the possibility of using stem cells in attempts to regenerate spinal cord and brain injuries. Methods: Selected articles from Pubmed and specialist textbooks were analyzed in detail. We focused on selected disease states in which stem cells may have therapeutic possibilities. Conclusion: Currently, cell therapies are mainly used in bone marrow diseases such as leukemias and myelodysplastic syndromes. If our level of knowledge allows it, in the future stem cells may become a tool in the fight against numerous diseases currently considered incurable and help in the regeneration of organs with a low degree of self-renewal, such as the spinal cord and brain, but also the heart, pancreas and many others.

Neuroprotective potential of traditionally used medicinal plants of Manipur against rotenone-induced neurotoxicity in SH-SY5Y neuroblastoma cells

Ethnopharmacological relevanceAlternanthera sessilis (L.) R. Br. ex DC., Eryngium foetidum L., and Stephania japonica (Thunb.) Miers plants are traditionally used to treat various central nervous system disorders like paralysis, epilepsy, seizure, convulsion, chronic pain, headache, sleep disturbances, sprain, and mental disorders. However, their possible neuroprotective effects have not been evaluated experimentally so far. Aim of the studyThe study aims to examine the neuroprotective potential of the three plants against cytotoxicity induced by rotenone in SH-SY5Y neuroblastoma cells and assess its plausible mechanisms of neuroprotection. Materials and methodsThe antioxidant properties of the plant extracts were determined chemically by DPPH and ABTS assay methods. The cytotoxicity of rotenone and the cytoprotective activities of the extracts were evaluated using MTT assays. Microtubule-associated protein 2 (MAP2) expression studies in cells were performed to assess neuronal survival after rotenone and extract treatments. Mitochondrial membrane potential and intracellular levels of reactive oxygen species were evaluated using Rhodamine 123 and DCF-DA dye, respectively. Catalase, glutathione peroxidase, and superoxide dismutase activities were also measured. Apoptotic nuclei were examined using DAPI staining. Liquid chromatography-quadrupole time-of-flight tandem mass spectrometry (LC-QTOF-MS) analysis of the plant extracts was also performed. ResultsThe methanol extracts of A. sessilis, S. japonica, and E. foetidum showed excellent free radical scavenging activities. MAP2 expression studies show that A. sessilis and S. japonica have higher neuroprotective effects against rotenone-induced neurotoxicity in SH-SY5Y cells than E. foetidum. Pre-treating cells with the plant extracts reverses the rotenone-induced increase in intracellular ROS. The plant extracts could also restore the reduced mitochondrial membrane potential induced by rotenone treatment and reinstate rotenone-induced increases in catalase, glutathione peroxidase, and superoxide dismutase activities. All the extracts inhibited rotenone-induced changes in nuclear morphology and DNA condensation, an early event of cellular apoptosis. LC-QTOF-MS analysis of the plant extracts shows the presence of neuroprotective compounds. ConclusionsThe plant extracts showed neuroprotective activities against rotenone-treated SH-SY5Y cells through antioxidant and anti-apoptotic mechanisms. These findings support the ethnopharmacological uses of these plants in treating neurological disorders. They probably are a good source of neuroprotective compounds that could be further explored to develop treatment strategies for neurodegenerative diseases like Parkinson's disease.

Roadmap for the next decade of plant programmed cell death research.

Programmed cell death (PCD) is fundamentally important for plant development, abiotic stress responses and immunity, but our understanding of its regulation remains fragmented. Building a stronger research community is required to accelerate progress in this area through knowledge exchange and constructive debate. In this Viewpoint, we aim to initiate a collective effort to integrate data across a diverse set of experimental models to facilitate characterisation of the fundamental mechanisms underlying plant PCD and ultimately aid the development of a new plant cell death classification system in the future. We also put forward our vision for the next decade of plant PCD research stemming from discussions held during the 31st New Phytologist workshop, 'The Life and Death Decisions of Plant Cells' that took place at University College Dublin in Ireland (14-15 June 2023). We convey the key areas of significant progress and possible future research directions identified, including resolving the spatiotemporal control of cell death, isolation of its molecular and genetic regulators, and harnessing technical advances for studying PCD events in plants. Further, we review the breadth of potential impacts of plant PCD research and highlight the promising new applications of findings from this dynamically evolving field.

A matter of new life and cell death: programmed cell death in the mammalian ovary.

The mammalian ovary is a unique organ that displays a distinctive feature of cyclic changes throughout the entire reproductive period. The estrous/menstrual cycles are associated with drastic functional and morphological rearrangements of ovarian tissue, including follicular development and degeneration, and the formation and subsequent atrophy of the corpus luteum. The flawless execution of these reiterative processes is impossible without the involvement of programmed cell death (PCD). PCD is crucial for efficient and careful clearance of excessive, depleted, or obsolete ovarian structures for ovarian cycling. Moreover, PCD facilitates selection of high-quality oocytes and formation of the ovarian reserve during embryonic and juvenile development. Disruption of PCD regulation can heavily impact the ovarian functions and is associated with various pathologies, from a moderate decrease in fertility to severe hormonal disturbance, complete loss of reproductive function, and tumorigenesis. This comprehensive review aims to provide updated information on the role of PCD in various processes occurring in normal and pathologic ovaries. Three major events of PCD in the ovary-progenitor germ cell depletion, follicular atresia, and corpus luteum degradation-are described, alongside the detailed information on molecular regulation of these processes, highlighting the contribution of apoptosis, autophagy, necroptosis, and ferroptosis. Ultimately, the current knowledge of PCD aberrations associated with pathologies, such as polycystic ovarian syndrome, premature ovarian insufficiency, and tumors of ovarian origin, is outlined. PCD is an essential element in ovarian development, functions and pathologies. A thorough understanding of molecular mechanisms regulating PCD events is required for future advances in the diagnosis and management of various disorders of the ovary and the female reproductive system in general.

Acetaminophen Hepatotoxicity: Paradigm for Understanding Mechanisms of Drug-Induced Liver Injury.

Acetaminophen (APAP) overdose is the clinically most relevant drug hepatotoxicity in western countries, and, because of translational relevance of animal models, APAP is mechanistically the most studied drug. This review covers intracellular signaling events starting with drug metabolism and the central role of mitochondrial dysfunction involving oxidant stress and peroxynitrite. Mitochondria-derived endonucleases trigger nuclear DNA fragmentation, the point of no return for cell death. In addition, adaptive mechanisms that limit cell death are discussed including autophagy, mitochondrial morphology changes, and biogenesis. Extensive evidence supports oncotic necrosis as the mode of cell death; however, a partial overlap with signaling events of apoptosis, ferroptosis, and pyroptosis is the basis for controversial discussions. Furthermore, an update on sterile inflammation in injury and repair with activation of Kupffer cells, monocyte-derived macrophages, and neutrophils is provided. Understanding these mechanisms of cell death led to discovery of N-acetylcysteine and recently fomepizole as effective antidotes against APAP toxicity.

Enhancing Liver Delivery of Gold Nanoclusters via Human Serum Albumin Encapsulation for Autoimmune Hepatitis Alleviation.

Peptide-protected gold nanoclusters (AuNCs), possessing exceptional biocompatibility and remarkable physicochemical properties, have demonstrated intrinsic pharmaceutical activity in immunomodulation, making them a highly attractive frontier in the field of nanomedicine exploration. Autoimmune hepatitis (AIH) is a serious autoimmune liver disease caused by the disruption of immune balance, for which effective treatment options are still lacking. In this study, we initially identified glutathione (GSH)-protected AuNCs as a promising nanodrug candidate for AIH alleviating in a Concanavalin A (Con A)-induced mice model. However, to enhance treatment efficiency, liver-targeted delivery needs to be improved. Therefore, human serum albumin (HSA)-encapsulated AuNCs were constructed to achieve enhanced liver targeting and more potent mitigation of Con A-induced elevations in plasma aspartate transaminase (AST), alanine transaminase (ALT), and liver injury in mice. In vivo and in vitro mechanism studies indicated that AuNCs could suppress the secretion of IFN-γ by Con A-stimulated T cells and subsequently inhibit the activation of the JAK2/STAT1 pathway and eventual hepatocyte apoptosis induced by IFN-γ. These actions ultimately protect the liver from immune cell infiltration and damage caused by Con A. These findings suggest that bio-protected AuNCs hold promise as nanodrugs for AIH therapy, with their liver targeting capabilities and therapeutic efficiency being further improved via rational surface ligand engineering.

Caspase cleavage of RIPK3 after Asp333 is dispensable for mouse embryogenesis

The proteolytic activity of caspase-8 suppresses lethal RIPK1-, RIPK3- and MLKL-dependent necroptosis during mouse embryogenesis. Caspase-8 is reported to cleave RIPK3 in addition to the RIPK3-interacting kinase RIPK1, but whether cleavage of RIPK3 is crucial for necroptosis suppression is unclear. Here we show that caspase-8-driven cleavage of endogenous mouse RIPK3 after Asp333 is dependent on downstream caspase-3. Consistent with RIPK3 cleavage being a consequence of apoptosis rather than a critical brake on necroptosis, Ripk3D333A/D333A knock-in mice lacking the Asp333 cleavage site are viable and develop normally. Moreover, in contrast to mice lacking caspase-8 in their intestinal epithelial cells, Ripk3D333A/D333A mice do not exhibit increased sensitivity to high dose tumor necrosis factor (TNF). Ripk3D333A/D333A macrophages died at the same rate as wild-type (WT) macrophages in response to TNF plus cycloheximide, TNF plus emricasan, or infection with murine cytomegalovirus (MCMV) lacking M36 and M45 to inhibit caspase-8 and RIPK3 activation, respectively. We conclude that caspase cleavage of RIPK3 is dispensable for mouse development, and that cleavage of caspase-8 substrates, including RIPK1, is sufficient to prevent necroptosis.

Joint Analysis of Genome-wide DNA Methylation and Transcription Sequencing Identifies the Role of BAX Gene in Heat Stress-Induced-Sertoli Cells Apoptosis.

The problem of male infertility is a global health crisis and poses a serious threat to the well-being of families. Under heat stress (HS), the reduction of Sertoli cells (SCs) inhibits energy transport and nutrient supply to germ cells, leading to spermatogenesis failure. DNA methylation of genes is a central epigenetic regulatory mechanism in mammalian reproduction. However, it remains unclear how DNA methylation regulates gene expression in heat-stressed SCs. In this study, we investigated whether the decrease in SC levels during HS could be related to epigenetic DNA modifications. The cells exposed to HS showed changes in differential methylation cytosines and regions (DMCs/DMRs) and differential expression genes (DEGs), but not in global DNA methylations. One of the most important biological processes affected by HS is cell apoptosis induced by the intrinsic apoptotic signaling pathway (GO: 2,001,244, P < 0.05) by enrichment in the Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG). The joint analysis showed that several gene expressions in RNA-seq and WGBS overlapped and the shortlisted genes BAX, HSPH1, HSF1B, and BAG were strongly correlated with stress response and apoptosis. Methylation-specific PCR (MSP) and flow cytometry (FCM) analyzes showed that reduced promoter methylation and enhanced gene expression of BAX with a consequence of apoptosis. The activity of BAX, as well as an increase in its expression, is likely to result in a reduction of SCs population which could further impair ATP supply and adversely affect membrane integrity. These findings provide novel insights into the molecular mechanisms through which stressors cause male reproductive dysfunction and a new molecular etiology of male infertility.

Small-molecule agonist AdipoRon alleviates diabetic retinopathy through the AdipoR1/AMPK/EGR4 pathway.

Diabetes mellitus (DM) is a progressive disease that involves multiple organs due to increased blood glucose, and diabetic retinopathy (DR) is the main complication of DM in the eyes and causes irreversible vision loss. In the pathogenesis of diabetic vascular disease, oxidative stress caused by hyperglycemia plays an important role in Müller cell impairment. In recent years, AdipoRon, an adiponectin analog that demonstrated important physiological functions in obesity, diabetes, inflammation, and cardiovascular diseases, demonstrated cellular protection from apoptosis and reduced inflammatory damage through a receptor-dependent mechanism. Here, we investigated how AdipoRon reduced oxidative stress and apoptosis in Müller glia in a high glucose environment. By binding to adiponectin receptor 1 on Müller glia, AdipoRon activated 5' adenosine monophosphate-activated protein kinase (AMPK)/acetyl-CoA carboxylase phosphorylation downstream, thereby alleviating oxidative stress and eventual apoptosis of cells and tissues. Transcriptome sequencing revealed that AdipoRon promoted the synthesis and expression of early growth response factor 4 (EGR4) and inhibited the cellular protective effects of AdipoRon in a high-glucose environment by reducing the expression of EGR4. This indicated that AdipoRon played a protective role through the EGR4 and classical AMPK pathways. This provides a new target for the early treatment of DR.

Recent advances in FRET probes for mitochondrial imaging and sensing.

Mitochondria, as essential organelles in cells, play a crucial role in cellular growth and apoptosis. Monitoring mitochondria is of great importance, as mitochondrial dysfunction is often considered a hallmark event of cell apoptosis. Traditional fluorescence probes used for mitochondrial imaging and sensing are mostly intensity-based and are susceptible to factors such as concentration, the probe environment, and fluorescence intensity. Probes based on fluorescence resonance energy transfer (FRET) can effectively overcome external interference and achieve high-contrast imaging of mitochondria as well as quantitative monitoring of mitochondrial microenvironments. This review focuses on recent advances in the application of FRET-based probes for mitochondrial structure imaging and microenvironment sensing.

Perturbation of IP3R-dependent endoplasmic reticulum calcium homeostasis by PPARδ-activated metabolic stress leads to mouse spermatocyte apoptosis: A direct mechanism for perfluorooctane sulfonic acid-induced spermatogenic disorders

Perfluorooctane sulfonic acid (PFOS) as an archetypal representative of per- and polyfluoroalkyl substances (PFAS) is ubiquitously distributed in the environment and extensively detected in human bodies. Although accumulating evidence is suggestive of the deleterious effects of PFOS on male reproduction, the direct toxicity of PFOS towards spermatogenic cells and the relevant mechanisms remain poorly understood. The aims of the present study were to explore the direct effects and underlying molecular mechanisms of PFOS on spermatogenesis. Through integrating animal study, transcriptome profiling, in silico toxicological approaches, and in vitro validation study, we identified the molecular initiating event and key events contributing to PFOS-induced spermatogenic impairments. The mouse experiments revealed that spermatocytes were involved in PFOS-induced spermatogenic disorders and the activation of peroxisome proliferator-activated receptor delta (PPARδ) was linked to spermatocyte loss in PFOS-administrated mice. GC-2spd(ts) cells were treated with an increased gradient of PFOS, which was relevant to environmental and occupational exposure levels of PFOS in populations. Following 72-h treatment, cells was harvested for RNA sequencing. The transcriptome profiling and benchmark dose (BMD) modeling identified endoplasmic reticulum (ER) stress as the key event for PFOS-mediated spermatocyte apoptosis and determined the point-of-departure (PoD) for perturbations of ER stress signaling. Based on the calculated PoD value, further bioinformatics analyses combined with in vitro and in vivo validations showed that PFOS caused metabolic stress by activating PPARδ in mouse spermatocytes, which was responsible for Beclin 1-involved inositol 1,4,5-trisphosphate receptor (IP3R) sensitization. The disruption of IP3R-mediated ER calcium homeostasis triggered ER calcium depletion, leading to ER stress and apoptosis in mouse spermatocytes exposed to PFOS. This study systematically investigated the direct impacts of PFOS on spermatogenesis and unveiled the relevant molecular mechanism of PFOS-induced spermatogenic disorders, providing novel insights and potential preventive/therapeutic targets for PFAS-associated male reproductive toxicity.