Boron Attenuates Heat Stress-Induced Apoptosis by Inhibiting Endoplasmic Reticulum Stress in Mouse Granulosa Cells

Sigma-1 Receptor-Mediated High Mobility Group A1 Silencing Alleviates Endoplasmic Reticulum Stress-Induced Ovarian Granulosa Cell Apoptosis: An In Vitro Cell Experimental Study

OBJECTIVE

To investigate the role and underlying mechanism of sigma-1 receptor (SigmaR1)/high mobility group A1 (HMGA1) in the pathogenesis of diminished ovarian reserve (DOR).

DESIGN

In vitro cell experimental study.

SETTING

The Reproductive Medical Center, People's Hospital of Zhengzhou University.

SAMPLE

Serum, follicular fluid (FF), ovarian granulosa cells (GCs) and KGN cells.

METHODS

Samples were collected from DOR patients. Endoplasmic reticulum (ER) stress was induced in the GCs using thapsigargin (TG). mRNA and protein levels were determined using reverse transcription-quantitative polymerase chain reaction and western blotting. Cell apoptosis and viability were assessed using flow cytometry and cell counting kit-8. Protein colocalization was detected via immunofluorescence. Molecular interactions were validated using co-immunoprecipitation, luciferase reporter and chromatin immunoprecipitation assays.

MAIN OUTCOME MEASURES

Cell viability, cell apoptosis, SigmaR1, HMGA1 and ER stress-associated mRNA levels.

RESULTS

SigmaR1 expression decreased while HMGA1 expression increased in the serum, FF and GC samples of DOR patients and TG-treated GCs. TG induced ER stress and GC apoptosis; these effects were diminished by SigmaR1 overexpression or HMGA1 silencing. SigmaR1 expressed in the nuclear envelope forms a complex with gene repressor-specific protein 3 (SP3) and histone deacetylase (HDAC)1/2/3; however, TG reduced SigmaR1 in GCs and blocked the complex formation. HMGA1, a transcriptional target of SP3, was negatively modulated by the SigmaR1/SP3 complex. HMGA1 overexpression abolished the protective effect of SigmaR1 on TG-induced ER stress and GC apoptosis.

CONCLUSION

SigmaR1 formed a SmigaR1/SP3/HDAC complex to inhibit HMGA1 transcription, alleviating ER stress and GC apoptosis and providing new therapeutic targets for DOR.

Boric Acid Alleviates Lipopolysaccharide-Induced Acute Lung Injury in Mice

Acute lung injury (ALI) poses a significant medical challenge due to its widespread occurrence and high mortality rates. Despite extensive efforts, current clinical interventions for ALI have shown limited success. Inflammation plays a central role within ALI progress, and boric acid (BA) has demonstrated anti-inflammatory properties both in vitro and in vivo. However, its potential to mitigate lipopolysaccharide (LPS)-induced ALI remains an area awaiting exploration in research. To bridge this research gap, we created a mouse model of ALI induced by intraperitoneal LPS injection. We employed a comprehensive set of evaluation criteria, including H&E staining, wet/dry ratio measurement, malondialdehyde (MDA)/superoxide dismutase (SOD) the oxidative stress-related biomarkers, assessment of alveolar edema, hemorrhage, inflammatory cell infiltration, and examination of thickened alveolar septum to quantify lung injury. Additionally, we measured inflammatory cytokine levels using ELISA and assessed Nrf2 and HO-1 expressions through western blotting and quantitative real-time PCR (RT-PCR). ER stress-related markers (GRP78, CHOP) were analyzed through western blot analysis. Our findings revealed that prophylactic treatment with BA effectively attenuated LPS-induced ALI, as supported by improved pathological alterations, decreased total protein concentration in bronchoalveolar lavage fluid (BALF), and reduced pulmonary edema. Furthermore, BA exhibited anti-inflammatory properties by suppressing inflammatory cytokines within the lung tissue. BA ingestion caused upregulation in SOD and a decrease in MDA contents in lung tissue homogenates. BA downregulated the levels of GRP78 and CHOP compared to the LPS group. Remarkably, BA also upregulated transcription and protein expression of Nrf2 and HO-1 compared to the LPS group. In conclusion, our study highlights BA's potential as a novel promising prophylactic agent for LPS-induced ALI, offering avenue for improving clinical management of this condition.

Alleviating heat stress-induced immune organ damage in ducks: Role of melittin

Heat stress, one of the major challenges facing the global livestock industry, can adversely affect the immune system. The present study explored the mechanisms by which melittin alleviates heat stress-induced immune organ damage. Three hundred 20-day-old male Huainan sheldrakes were randomly assigned to four groups: heat stress group (basal diet), heat stress + melittin group (I, II, III group, basal diet + 0.08, 0.12, 0.16 g/kg melittin, respectively). The ducks were subjected to heat stress for 4 h per day (temperature 36-38 °C, relative humidity 60-70%) for 15 consecutive days. The results showed that compared with the heat-stress group, melittin improved the production performance of heat-stressed ducks, significantly increased serum immune indices (immunoglobulin G and interferon-gamma) and antioxidant indices (total antioxidant capacity, superoxide dismutase (SOD), and glutathione) (P < 0.05), and significantly decreased malondialdehyde (MDA) levels (P < 0.05). Additionally, melittin increased antioxidant function (nuclear factor-erythroid 2 p45-related factor 2, glutathione peroxidase, SOD, and catalase), and immune index (interleukin-10). Meanwhile, melittin significantly reduced immune indices (inducible nitric oxide synthase and cyclooxygenase-2), heat shock protein 70 expression, and apoptosis levels (P < 0.05) in heat-stressed ducks. Consequently, supplementing heat-stressed ducks with 0.12 g/kg melittin increases serum immune function and antioxidants, alleviate heat stress-induced immune organ damage, and improve growth performance.

Trace elements and metal nanoparticles: mechanistic approaches to mitigating chemotherapy-induced toxicity-a review of literature evidence

Anticancer chemotherapy (ACT) remains a cornerstone in cancer treatment, despite significant advances in pharmacology over recent decades. However, its associated side effect toxicity continues to pose a major concern for both oncology clinicians and patients, significantly impacting treatment protocols and patient quality of life. Current clinical strategies to mitigate ACT-induced toxicity have proven largely unsatisfactory, leaving a critical unmet need to block toxicity mechanisms without diminishing ACT's therapeutic efficacy. This review aims to document the molecular mechanisms underlying ACT toxicity and highlight research efforts exploring the protective effects of trace elements (TEs) and their nanoparticles (NPs) against these mechanisms. Our literature review reveals that the primary driver of ACT toxicity is redox imbalance, which triggers oxidative inflammation, apoptosis, endoplasmic reticulum stress, mitochondrial dysfunction, autophagy, and dysregulation of signaling pathways such as PI3K/mTOR/Akt. Studies suggest that TEs, including zinc, selenium, boron, manganese, and molybdenum, and their NPs, can potentially counteract ACT-induced toxicity by inhibiting oxidative stress-mediated pathways, including NF-κB/TLR4/MAPK/NLRP3, STAT-3/NLRP3, Bcl-2/Bid/p53/caspases, and LC3/Beclin-1/CHOP/ATG6, while also upregulating protective signaling pathways like Sirt1/PPAR-γ/PGC-1α/FOXO-3 and Nrf2/HO-1/ARE. However, evidence regarding the roles of lncRNA and the Wnt/β-catenin pathway in ACT toxicity remains inconsistent, and the impact of TEs and NPs on ACT efficacy is not fully understood. Further research is needed to confirm the protective effects of TEs and their NPs against ACT toxicity in cancer patients. In summary, TEs and their NPs present a promising avenue as adjuvant agents for preventing non-target organ toxicity induced by ACT.

Environmental high temperature affects pre-implantation embryo development by impairing the DNA repair ability

Environmental high temperature poses a significant threat to human health, however, limited information is available for understanding the relationship between the hot weather and infertility. This study aims to assess the adverse effect of the hot weather to early embryonic cells. Our results indicated that environmental high temperature exposure could cause the decline of early embryo quality and implantation ability. In detail, it led to early embryonic development retardation, embryo degeneration rate increased, the rate of blastocyst and hatching decreased, and reduced the number of implants. And the finding also the impairment of environmental high temperature on early embryonic cells may be due to oxidative damage of DNA caused by ROS, while BER repair ability is decreased, failing to repair oxidative damage of DNA in time, resulting in a large number of early embryonic apoptosis. The work underscored that pregnant women should stay away from high-temperature environments.

Advances in the Effects of Heat Stress on Ovarian Granulosa Cells: Unveiling Novel Ferroptosis Pathways

Heat stress has been one of the key research areas for researchers due to the wide-ranging effects and complex mechanisms of action of its stress product reactive oxygen species (ROS). The aim of this paper is to comprehensively review and summarize the effects of heat stress on ovarian granulosa cells and their mechanism of action. We systematically reviewed the effects of heat stress on ovarian granulosa cells, including intracellular steroid hormone changes, oxidative stress, apoptosis, and mitochondrial function. Meanwhile, this paper discusses in detail several major mechanisms by which heat stress induces apoptosis in ovarian granulosa cells, such as through the activation of apoptosis-related genes, induction of endoplasmic reticulum stress, and the mitochondrial pathway. In addition, we analyzed the mechanism of ferroptosis in ovarian granulosa cells under heat stress conditions, summarized the potential association between heat stress and ferroptosis in light of the existing literature, and explored the key factors in the mechanism of action of heat stress, such as the signaling pathways of Nrf2/Keap1, HSPs, and JNK, and analyzed their possible roles in the process of ferroptosis. Finally, this paper provides an outlook on the future research direction, describing the possible interaction between heat stress and ferroptosis, with a view to providing a theoretical basis for further understanding and revealing the complex mechanism of ferroptosis occurrence in ovarian granulosa cells under heat stress.

Advancements in Genetic Biomarkers and Exogenous Antioxidant Supplementation for Safeguarding Mammalian Cells against Heat-Induced Oxidative Stress and Apoptosis

Heat stress represents a pervasive global concern with far-reaching implications for the reproductive efficiency of both animal and human populations. An extensive body of published research on heat stress effects utilizes controlled experimental environments to expose cells and tissues to heat stress and its disruptive influence on the physiological aspects of reproductive phenotypic traits, encompassing parameters such as sperm quality, sperm motility, viability, and overall competence. Beyond these immediate effects, heat stress has been linked to embryo losses, compromised oocyte development, and even infertility across diverse species. One of the primary mechanisms underlying these adverse reproductive outcomes is the elevation of reactive oxygen species (ROS) levels precipitating oxidative stress and apoptosis within mammalian reproductive cells. Oxidative stress and apoptosis are recognized as pivotal biological factors through which heat stress exerts its disruptive impact on both male and female reproductive cells. In a concerted effort to mitigate the detrimental consequences of heat stress, supplementation with antioxidants, both in natural and synthetic forms, has been explored as a potential intervention strategy. Furthermore, reproductive cells possess inherent self-protective mechanisms that come into play during episodes of heat stress, aiding in their survival. This comprehensive review delves into the multifaceted effects of heat stress on reproductive phenotypic traits and elucidates the intricate molecular mechanisms underpinning oxidative stress and apoptosis in reproductive cells, which compromise their normal function. Additionally, we provide a succinct overview of potential antioxidant interventions and highlight the genetic biomarkers within reproductive cells that possess self-protective capabilities, collectively offering promising avenues for ameliorating the negative impact of heat stress by restraining apoptosis and oxidative stress.

Silencing PKM2 Attenuates Brain Injury Induced by Status Epilepticus by Inhibiting the AKT/mTOR Pathway and the NLRP3 Inflammasome

PKM2 is a glycolytic pyruvate kinase isoenzyme, and its role in neurological diseases has been published. However, the role and mechanism of PKM2 in the process of status epilepticus have not been reported. The purpose of this study is to explore the role and mechanism of PKM2 in epilepsy. Quantitative real-time polymerase chain reaction (qRT-PCR) and western blotting were used to explore the expression of PKM2 in cells. Enzyme-linked immunosorbent assay kits were used to evaluate the level of inflammatory factors. An epilepsy model was established by intraperitoneal injection of lithium chloride in rats. Various behavioural assays were conducted to explore the learning ability and cognitive level of rats. PKM2 expression was upregulated in Mg2+-induced hippocampal neurons. PKM2 inhibition ameliorated Mg2+-induced hippocampal neuronal inflammation and reduced neuronal apoptosis. In addition, PKM2 silencing inhibited the metabolic dysfunction of Mg2+-induced hippocampal neurons. Subsequent experiments showed that the Akt/mTOR pathway and NLRP3 inflammasome are involved in PKM2-mediated neuronal regulation. More importantly, PKM2 inhibition could alleviate status epilepticus in rats. PKM2 inhibition attenuates Mg2+-induced hippocampal neuronal inflammation, apoptosis and metabolic dysfunction and improves the cognitive ability of rats. Therefore, PKM2 may be an important target for epilepsy treatment.

Integration of transcriptome and proteome analyses reveals the regulation mechanisms of Larimichthys polyactis liver exposed to heat stress

Small yellow croaker (Larimichthys polyactis) is one of the most economically important marine fishery species. L. polyactis aquaculture has experienced stress response and the frequent occurrence of diseases, bringing huge losses to the aquaculture industry. Little is known about the regulation mechanism of heat stress response in L. polyactis. In this study, to provide an overview of the heat-tolerance mechanism of L. polyactis, the transcriptome and proteome of the liver of L. polyactis on the 6 h after high temperature (32 °C) treatment were analyzed using Illumina HiSeq 4000 platform and isobaric tag for relative and absolute quantitation (iTRAQ). A total of 3700 upregulated and 1628 downregulated genes (differentially expressed genes, DEGs) were identified after heat stress in L. polyactis. Also, 198 differentially expressed proteins (DEPs), including 117 upregulated and 81 downregulated proteins, were identified. Integrative analysis revealed that 72 genes were significantly differentially expressed at transcriptome and protein levels. Functional analysis showed that arginine biosynthesis, tyrosine metabolism, pentose phosphate pathway, starch and sucrose metabolism, and protein processing in the endoplasmic reticulum were the main pathways responding to heat stress. Among the pathways, protein processing in the endoplasmic reticulum was enriched by most DEGs/DEPs, which suggests that this pathway may play a more important role in the heat stress response. Further insights into the pathway revealed that transcripts and proteins, especially HSPs and PDIs, were differentially expressed in response to heat stress. These findings contribute to existing data describing the fish response to heat stress and provide information about protein levels, which are of great significance to a deeper understanding of the heat stress responding regulation mechanism in L. polyactis and other fish species.

Boron enhances adaptive responses and biological performance via hormetic mechanisms

Boron is shown in the present review to induce hormetic dose responses in a broad range of biological models, organ systems and endpoints. Of particular importance is that numerous hormetic findings have been reported with whole animal studies, with extensive dose response evaluations with the optimal dosing being similar across multiple organ systems. These findings appear to be underappreciated and suggest that boron may have clinically significant systemic effects beyond that of its putative and more subtle essentiality functions. The re-exploration of boron's bioactivity as seen through hormetic mechanisms may also underscore the value of this approach to the assessment of micronutrient effects in human health and disease.

Geniposide attenuates spermatogenic dysfunction via inhibiting endoplasmic reticulum stress in male mice

BACKGROUND

Spermatogenesis dysfunction is common in clinically infertile patients. Geniposide (GP) is one of the important active ingredients extracted from Eucommia ulmoides. However, the protective effect and mechanism of GP in the treatment of spermatogenic dysfunction is not known yet.

METHODS

After cyclophosphamide-induced spermatogenic dysfunction was established in male mice, we gavaged GP for 4 weeks to evaluate spermatogenic function and anti-apoptotic effects by fertility, testicular weight, sperm quality, endoplasmic reticulum stress (ER stress), comet assay and serum testosterone level.

RESULTS

GP can improve the damage of fertility and reproductive organs induced by cyclophosphamide and increase the number and activity of sperm. In comet assay, it was found that GP administration could alleviate sperm DNA damage induced by cyclophosphamide. In addition, GP treatment can significantly reduce ThT fluorescence intensity and improve endoplasmic reticulum stress induced by cyclophosphamide. Besides, TUNEL staining and WB showed that GP could inhibit the excessive apoptosis of cells and protect testis. (p < 0.05, p < 0.01, p < 0.001).

CONCLUSION

The protective effect of Geniposide on cyclophosphamide-induced spermatogenic dysfunction in mice is related to the inhibition of endoplasmic reticulum stress.

Etanercept Protected Against Cigarette Smoke Extract-Induced Inflammation and Apoptosis of Human Pulmonary Artery Endothelial Cells via Regulating TNFR1

Purpose

Etanercept (ETN), a tumor necrosis factor-α (TNF-α) inhibitor, has been applied in the treatment of many diseases. However, whether it has effects on chronic obstructive pulmonary disease (COPD) and its interaction with tumor necrosis factor receptor 1 (TNFR1) remained unknown.

Methods

Histopathological analysis of lung tissues from non-smokers and smokers with or without COPD was conducted using hematoxylin–eosin (H&E) staining, Van Gieson (VG) staining, and terminal transferase-mediated biotin dUTP nick end labeling (TUNEL). TNF-α content was measured using Immunohistochemistry. Correlation analysis among apoptosis rate, smoke index, the FEV1/FVC ratio, and TNF-α-positive cells was performed. After ETN treatment and transfection of overexpressed or silenced TNFR1, levels of inflammatory cytokines, apoptosis and related genes expressions in cigarette smoke extract (CSE)-treated human pulmonary artery endothelial cells (HPAECs) were detected using enzyme-linked immunosorbent assay (ELISA), Hoechst 33342 staining, flow cytometry, quantitative real-time PCR (qRT-PCR) and Western blot.

Results

Pulmonary arterial remodeling and increased apoptotic and TNF-α⁺ HPAECs were found in lung tissue of smokers with or without COPD, with higher degrees in smokers with COPD. The numbers of apoptotic and TNF-α⁺ HPAECs were positively correlated with smoke index, while the FEV1/FVC ratio was negatively correlated with apoptotic HPAECs. In HPAECs, ETN downregulated the expressions of proteins related to CSE-induced apoptosis and the TNF receptor family, decreased CSE-induced cell apoptosis and inflammatory cytokine levels, and inhibited TNFR1 expression and p65 phosphorylation. Overexpressed TNFR1 reversed the effects of ETN on CSE-treated HPAECs, whereas silencing TNFR1 did the opposite.

Conclusion

ETN protected HPAECs against CSE-induced inflammation and apoptosis via downregulating TNFR1, thus providing a potential therapy for smoking-induced COPD.

Overexpression of long non-coding RNA XIST promotes IL-1β-induced degeneration of nucleus pulposus cells through targeting miR-499a-5p

BACKGROUND

Long non-coding RNA X-interactive specific transcript (XIST) is implicated in many diseases. However, its role and interaction with microRNA (miR)-499a-5p in intervertebral disc degeneration (IDD) remained unclear.

METHODS

Nucleus pulposus (NP) tissue samples were collected and nucleus pulposus cells (NPCs) were isolated for Interleukin-1β (IL-1β) treatment and identification. XIST and miR-499a-5p expressions in the tissue were measured with quantitative real-time polymerase chain reaction (qRT-PCR). After IL-1β treatment, NPC apoptosis was detected by flow cytometry. The potential binding sites of XIST and miR-499a-5p were predicted by starBase and confirmed by dual-luciferase reporter assay. Relative expressions of tissue inhibitor of metalloproteinases-3 (TIMP-3), Matrix metalloproteinases-3 (MMP-3), MMP-13, Collagen II, Aggrecan and apoptosis-related proteins (Bcl-2 associated X protein, Bax; B-cell lymphoma 2, Bcl-2; cleaved caspase-3) were measured by qRT-PCR and Western blot as needed.

RESULTS

XIST expression was upregulated in the NP tissues of patients with IDD, and IL-1β treatment resulted in a degradation of NPCs. Overexpressed XIST promoted the effects of IL-1β on increasing NPC apoptosis and expressions of XIST, MMP-3, MMP-13, Bax and Cleaved caspase-3, but down-regulated TIMP-3, Collagen II, Aggrecan and Bcl-2 expressions. Silencing XIST, however, showed the opposite effects to its overexpression. MiR-499a-5p expression was downregulated in NP tissues of IDD patients and could bind with XIST, while its upregulation reversed the effects of overexpressed XIST in the IL-1β-treated NPCs.

CONCLUSION

Overexpressed XIST caused NPC degeneration through promoting apoptosis and extracellular matrix degradation of IL-1β-treated NPCs through targeting miR-499a-5p, and therefore can serve as a potential treatment for IDD.

miR-139-5p upregulation alleviated spontaneous recurrent epileptiform discharge-induced oxidative stress and apoptosis in rat hippocampal neurons via regulating the Notch pathway

Epilepsy was characterized by the occurrence of spontaneous recurrent epileptiform discharges (SREDs) in neurons. Previous studies suggested that microRNA (miR)-139-5p and the Notch pathway were implicated in epilepsy; however, their interaction remained vague. Rat primary hippocampal neurons were isolated and identified by immunofluorescence staining. The cells were then used for SREDs model construction and further subjected to flow cytometry for apoptosis detection. Contents of lactate dehydrogenase (LDH), malondialdehyde (MDA), super oxidase dismutase (SOD) contents, and reactive oxygen species (ROS), and the level of mitochondrial membrane potential (MMP) were determined using commercial kits. Target gene and potential binding sites of miR-139-5p were predicted with TargetScan and confirmed by dual-luciferase reporter assay. Expressions of miR-139-5p, Notch pathway-related proteins and apoptosis-related proteins were measured by quantitative real-time polymerase chain reaction and western blot as needed. The results showed that the hippocampal neurons were microtubule-associated protein 2 (MAP2)-positive. miR-139-5p was downregulated in SREDs model cells. SREDs promoted apoptosis and increased the contents of LDH, MDA, and ROS and the level of MMP while reducing miR-139-5p expression and SOD content in cells, which was reversed by miR-139-5p overexpression. Notch-1 was recognized as the target gene of miR-139-5p, and its expression was negatively regulated by miR-139-5p. Besides, Notch-1 overexpression reversed the effects of miR-139-5p upregulation on the expressions of Notch pathway-related proteins and apoptosis-related proteins, cell apoptosis, oxidative stress and MMP in SREDs-treated cells. Our results indicated that miR-139-5p upregulation alleviated SREDs-induced oxidative stress and cell apoptosis via regulating the Notch pathway, which provides new insights into the role of miRNA in the occurrence and development of epilepsy.