miR-484 mediates oxidative stress-induced ovarian dysfunction and promotes granulosa cell apoptosis via SESN2 downregulation

LH promotes the proliferation of porcine primordial germ cell-like cells (pPGCLCs) by regulating the ceRNA network related to the TGF-β signaling pathway

Primordial germ cells (PGCs), as the precursors of gametes found in early embryos, provide a new direction for solving the problem of reproductive disorders. In vitro, conversion of adult stem cells (ASCs) into primordial germ cell-like cells (PGCLCs) is feasible. The means of increasing PGCLCs number in vitro has been a focus of recent stem cell research. In this study, we found that luteinizing hormone (LH) could promote porcine PGCLCs (pPGCLCs) proliferation. To investigate the proliferation regulatory network, whole transcriptome sequencing technology was employed. Results showed that the TGF-β signaling pathway played a key role. In addition, we found that TGFβR1 and SMAD4, TGF-β signaling pathway-related genes, were significantly upregulated after LH treatment. Subsequently, we predicted their target microRNAs (miRNAs) and long non-coding RNAs (lncRNAs): ssc-miR-128, ssc-miR-146b, ssc-miR-361-3p, MSTRG.11473, MSTRG.11475, MSTRG.11553, and MSTRG.11554, and constructed the competitive endogenous RNAs (ceRNA) network. Finally, to further verify the ceRNA network, the miRNA-inhibitors were transfected into cells. RT-qPCR results indicated a significant increase in the expression of MSTRG.11473, MSTRG.11475, MSTRG.11553, MSTRG.11554, TGFβR1, and SMAD4 compared to the negative control (NC) group. In conclusion, these results highlight that LH could regulate the pPGCLCs proliferation by modulating the expression of TGF-β signaling pathway-related ncRNAs.

T-2 toxin exposure induces ovarian damage in sows: lncRNA CUFF.253988.1 promotes cell apoptosis by inhibiting the SIRT3/PGC1α pathway

T-2 toxin, a mycotoxin found in foods and feeds, poses a threat to female reproductive health in both humans and animals. LncRNA CUFF.253988.1 (CUFF.253988.1), highly expressed in pigs, has an undisclosed regulatory role. This study aimed to establish a model of T-2 toxin-induced ovarian injury in sows, both in vivo and in vitro, and to explore the regulatory role and potential mechanisms of CUFF.253988.1. The results showed that feeding T-2 toxin-contaminated feed (1 mg/kg) induced ovarian follicle atresia and mitochondrial structural damage, accompanied by a significant upregulation of CUFF.253988.1 expression in the ovaries. Additionally, T-2 toxin inhibited the SIRT3/PGC1-α pathway associated with mitochondrial function. Moreover, T-2 toxin induced cell apoptosis by upregulating the expression of Cyt c, Bax, cleaved-caspase-9, and cleaved-caspase-3 proteins. In T-2 toxin-induced injury to the ovarian granulosa AVG-16 cells at concentrations of 10, 40 and 160 nM, not only were the previously mentioned effects observed, but also a decrease in mitochondrial membrane potential, ATP content, and an elevation in ROS levels. However, downregulating CUFF.253988.1 reversed T-2 toxin's inhibition of the SIRT3/PGC1-α pathway, alleviating mitochondrial dysfunction and reducing cell apoptosis. Notably, this may be attributed to the inhibition of T-2 toxin-induced enrichment of CUFF.253988.1 in mitochondria. In conclusion, CUFF.253988.1 plays a pivotal role in T-2 toxin-induced ovarian damage, operating through the inhibition of the SIRT3/PGC1-α pathway and promotion of cell apoptosis.

Effects of Melatonin and 3,5,3'-Triiodothyronine on the Development of Rat Granulosa Cells

Melatonin, as an endocrine neurotransmitter, can promote the development of the ovary. Meanwhile, it also has protective effect on the ovary as an antioxidant. Thyroid hormone (TH) is essential for normal human reproductive function. Many studies have shown that 3,5,3'-triiodothyronine (T3) regulates the development of ovarian granulosa cells. However, little is known about the specific mechanisms by which melatonin combines with T3 to regulate granulosa cell development. The aim of present study was to investigate the effects and the possible mechanisms of melatonin and T3 on ovarian granulosa cell development. In the present study, cell development and apoptosis were detected by CCK8, EdU and TUNEL, respectively. The levels of related proteins were analyzed by Western blotting. The results showed that oxidative stress (OS) and reactive oxygen species (ROS) were induced by H2O2 in granulosa cells, and cell apoptosis was also increased accompanied with the decreased cellular proliferation and viability. Melatonin protects granulosa cells from H2O2-induced apoptosis and OS by downregulating ROS levels, especially in the presence of T3. Co-treatment of cell with melatonin and T3 also promotes the expression of GRP78 and AMH, while inhibiting CHOP, Caspase-3, and P16. It was demonstrated that melatonin alone or in combination with T3 had positive effect on the development of granulosa cells. In addition, the AMPK/SIRT1 signaling pathway is involved in the process of melatonin/T3 promoting granulosa cell development.

Phospholipid Phosphatase 3 (PLPP3) Induces Oxidative Stress to Accelerate Ovarian Aging in Pigs

Ovarian aging results in reproductive disorders and infertility in mammals. Previous studies have reported that the ferroptosis and autophagy caused by oxidative stress may lead to ovarian aging, but the mechanisms remain unclear. In this study, we compared the morphological characteristics between the aged and young ovaries of pigs and found that the aged ovaries were larger in size and showed more corpora lutea. TUNEL assay further showed that the apoptosis level of granulosa cells (GCs) was relatively higher in the aged ovaries than those in young ovaries, as well as the expressions of autophagy-associated genes, e.g., p62, ATG7, ATG5, and BECN1, but that the expressions of oxidative stress and aging-associated genes, e.g., SOD1, SIRT1, and SIRT6, were significantly lower. Furthermore, the RNA-seq, Western blotting, and immunofluorescence suggested that phospholipid phosphatase 3 (PLPP3) protein was significantly upregulated in the aged ovaries. PLPP3 was likely to decrease the expressions of SIRT1 and SIRT6 to accelerate cellular senescence of porcine GCs, inhibit the expressions of SOD1, CAT, FSP1, FTH1, and SLC7A11 to exacerbate oxidative stress and ferroptosis, and arouse autophagy to retard the follicular development. In addition, two SNPs of PLPP3 promoter were significantly associated with the age at puberty. g.155798586 (T/T) and g.155798718 (C/C) notably facilitated the mRNA and protein level of PLPP3. In conclusion, PLPP3 might aggravate the oxidative stress of GCs to accelerate ovarian aging, and two molecular markers of PLPP3 were identified for ovarian aging in pigs. This work not only contributes to investigations on mechanisms for ovarian aging but also provides valuable molecular markers to postpone ovarian aging in populations.

Toxicity mechanism of acrolein on energy metabolism disorder and apoptosis in human ovarian granulosa cells

Acrolein (ACR), an unsaturated, highly reactive aldehyde, is a widespread environmental toxin. ACR exerts permanent and irreversible side effects on ovarian functions. Granulosa cells play a crucial role in supporting ovarian function. Thus, in this study, we investigated the toxicity effects of granulosa cells induced by ACR. Following treatment with varying ACR concentrations (0, 12.5, 25, 50, and 100 μM), we observed that ACR exposure induced reactive oxygen species accumulation, mitochondrial energy metabolism disorder, and apoptosis in KGN cells (a human ovarian granulosa cell line) in a dose-dependent manner. In addition, mitochondrial biogenesis in KGN cells displayed biphasic changes after ACR exposure, with activation at a low ACR dose (12.5 μM), but inhibition at higher ACR doses (≥50 μM). SIRT1/PGC-1α-mediated mitochondrial biogenesis is crucial for maintaining intracellular mitochondrial homeostasis and cellular function. The inhibition/activation of the SIRT1/PGC-1α pathway in KGN cells validated its role in ACR-induced damage. The results indicated that the inhibition of the SIRT1/PGC-1α pathway aggravated ACR-induced cell damage, whereas its activation partially counteracted ACR-induced cell damage. This study attempted to uncover a novel mechanism of ACR-induced ovarian toxicity so as to provide an effective treatment option for safeguarding female reproductive health from the adverse effects of ACR.

Pterostilbene, a Resveratrol Derivative, Improves Ovary Function by Upregulating Antioxidant Defenses in the Aging Chickens via Increased SIRT1/Nrf2 Expression

Oxidative stress is recognized as a prominent factor contributing to follicular atresia and ovarian aging, which leads to decreased laying performance in hens. Reducing oxidative stress can improve ovarian function and prolong the laying period in poultry. This study investigates the impact of Pterostilbene (PTS), a natural antioxidant, on ovarian oxidative stress in low-laying chickens. Thirty-six Hy-Line White laying chickens were evenly divided into four groups and fed diets containing varying doses of PTS for 15 consecutive days. The results showed that dietary supplementation with PTS significantly increased the laying rate, with the most effective group exhibiting a remarkable 42.7% increase. Furthermore, PTS significantly enhanced the antioxidant capacity of aging laying hens, as evidenced by increased levels of glutathione, glutathione peroxidase, superoxide dismutase, catalase, and total antioxidant capacity in the ovaries, livers, and serum. Subsequent experiments revealed decreased expressions of Bax, Caspase-3, and γ-H2AX, along with an increased expression of BCL-2 in the ovaries and livers of laying hens. PTS supplementation also positively affects fat metabolism by reducing abdominal fat accumulation and promoting fat transfer from the liver to the ovary. To elucidate the mechanism underlying the effects of PTS on ovarian function, a series of in vitro experiments were conducted. These in vitro experiments revealed that PTS pretreatment restored the antioxidant capacity of D-galactose-induced small white follicles by upregulating SIRT1/Nrf2 expression. This protective effect was inhibited by EX-527, a specific inhibitor of SIRT1. These findings suggest that the natural antioxidant PTS has the potential to regulate cell apoptosis and fat metabolism in laying chickens by ameliorating oxidative stress, thereby enhancing laying performance.

Paeoniflorin Promotes Ovarian Development in Mice by Activating Mitophagy and Preventing Oxidative Stress

During the development of animal organs, various adverse stimuli or toxic environments can induce oxidative stress and delay ovarian development. Paeoniflorin (PF), the main active ingredient of the traditional Chinese herb Paeonia lactiflora Pall., has protective effects on various diseases by preventing oxidative stress. However, the mechanism by which PF attenuates oxidative damage in mouse ovaries remains unclear. We evaluated the protective effects of PF on ovaries in an H2O2-induced mouse oxidative stress model. The H2O2-induced mouse ovarian oxidative stress model was used to explore the protective effect of PF on ovarian development. Histology and follicular development were observed. We then detected related indicators of cell apoptosis, oxidative stress, and autophagy in mouse ovaries. We found that PF inhibited H2O2-induced ovarian cell apoptosis and ferroptosis and promoted granulosa cell proliferation. PF prevented oxidative stress by increasing nuclear factor erythroid 2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1) expression levels. In addition, the autophagic flux of ovarian cells was activated and was accompanied by increased lysosomal biogenesis. Moreover, PF-mediated autophagy was involved in clearing mitochondria damaged by H2O2. Importantly, PF administration significantly increased the number of primordial follicles, primary follicles, secondary follicles, and antral follicles. PF administration improved ovarian sizes compared with the H2O2 group. The present study suggested that PF administration reversed H2O2-induced ovarian developmental delay and promoted follicle development. PF-activated mitophagy is crucial for preventing oxidative stress and improving mitochondrial quality.

Chromosome Segregation-1-like Gene Participates in Ferroptosis in Human Ovarian Granulosa Cells via Nucleocytoplasmic Transport

Premature ovarian insufficiency (POI) is defined as the depletion of ovarian function before the age of 40 years. The global prevalence of POI is 3.5%. To date, genetic factors account for 23.5% of the etiology of POI. Herein, a previously uncharacterized pathogenic homozygous variant of the chromosome segregation-1-like gene (CSE1L) was identified in POI patients via targeted panel sequencing. It is reported that dysregulated iron metabolism is involved in many reproductive endocrine disorders; however, its precise role in POI remains obscure. In this study, we identified CSE1L as a potential candidate gene that plays an important role in maintaining iron homeostasis. Deficiency of CSE1L led to ferroptosis in human granulosa cells, which was confirmed by transmission electron microscopy. Mechanistically, coimmunoprecipitation identified the direct interaction between CSE1L and FoxO1. Inhibition of CSE1L led to the excessive accumulation of FoxO1 in the nucleus via nucleocytoplasmic transport. Then, FoxO1 bound to the promoter region of NCOA4 and promoted its transcription, which was verified by a chromatin immunoprecipitation assay. Moreover, inhibition of CSE1L in cumulus cell monolayer could impede oocyte maturation, which might be associated with oxidative stress. Consequently, our study first revealed that CSE1L participated in ferroptosis in human ovarian granulosa cells via nucleocytoplasmic transportation, which might be helpful in revealing the molecular mechanism of CSE1L in the development of POI. Importantly, these findings might provide new insights into the application of ferroptosis inhibitors in the treatment of POI.

Melatonin regulates the antioxidant capacity of sheep granulosa cells through a novel uORF-Nrf2aa mediated Nrf2/KEAP1 pathway

Ovarian dysfunction stands as a prevalent contributor to female infertility, with its etiology intertwined with genetic, autoimmune, and environmental factors. Within the ovarian follicles, granulosa cells (GCs) represent the predominant cell population. Alterations in GCs, notably oxidative stress (OS) and the consequential surge in reactive oxygen species (ROS), play pivotal roles in the orchestration of ovarian function. Nrf2aa, a newly identified upstream open reading frame (uORF), is situated within the 5' untranslated region (5'UTR) of sheep Nrf2 mRNA and is regulated by melatonin, a crucial intrafollicular antioxidant. In this study, we have noted that Nrf2aa has the capacity to encode a peptide and exerts a negative regulatory effect on the translation efficiency (TE) of the Nrf2 CDs region. Further in vitro experiments, we observed that interfering with Nrf2aa can enhance the cellular functionality of GCs under 3-np-induced oxidative stress, while overexpressing Nrf2aa has the opposite effect. Furthermore, overexpression of Nrf2aa counteracts the rescuing effect of melatonin on the cellular functions of GCs under oxidative stress conditions, including estrogen secretion, proliferation, apoptosis, and many more. Finally, we confirmed that Nrf2aa, by regulating the expression of key proteins in the Nrf2/KEAP1 signaling pathway, further modulates the antioxidant levels in GCs.

M6A demethylase FTO-stabilized exosomal circBRCA1 alleviates oxidative stress-induced granulosa cell damage via the miR-642a-5p/FOXO1 axis

BACKGROUND

Premature ovarian insufficiency (POI) is an important cause of female infertility and seriously impacts the physical and psychological health of patients. Human umbilical cord mesenchymal stem cell-derived exosomes (HucMSCs-Exs, H-Exs) have exhibited protective effects on ovarian function with unclear mechanisms.

METHODS

A comprehensive analysis of the Gene Expression Omnibus (GEO) database were used to identify POI-associated circRNAs and miRNAs. The relationship between HucMSC-derived exosomal circBRCA1/miR-642a-5p/FOXO1 axis and POI was examined by RT-qPCR, Western blotting, reactive oxygen species (ROS) staining, senescence-associated β-gal (SA-β-gal) staining, JC-1 staining, TEM, oxygen consumption rate (OCR) measurements and ATP assay in vivo and in vitro. RT-qPCR detected the expression of circBRCA1 in GCs and serum of patients with normal ovarian reserve function (n = 50) and patients with POI (n = 50); then, the correlation of circBRCA1 with ovarian reserve function indexes was analyzed.

RESULTS

Herein, we found that circBRCA1 was decreased in the serum and ovarian granulosa cells (GCs) of patients with POI and was associated with decreased ovarian reserve. H-Exs improved the disorder of the estrous cycles and reproductive hormone levels, reduced the number of atretic follicles, and alleviated the apoptosis and senescence of GCs in rats with POI. Moreover, H-Exs mitigated mitochondrial damage and reversed the reduced circBRCA1 expression induced by oxidative stress in GCs. Mechanistically, FTO served as an eraser to increase the stability and expression of circBRCA1 by mediating the m6A demethylation of circBRCA1, and exosomal circBRCA1 sponged miR-642a-5p to block its interaction with FOXO1. CircBRCA1 insufficiency aggravated mitochondrial dysfunction, mimicking FTO or FOXO1 depletion effects, which was counteracted by miR-642a-5p inhibition.

CONCLUSION

H-Exs secreted circBRCA1 regulated by m6A modification, directly sponged miR-642a-5p to upregulate FOXO1, resisted oxidative stress injuries in GCs and protected ovarian function in rats with POI. Exosomal circBRCA1 supplementation may be a general prospect for the prevention and treatment of POI.

Dimethyl fumarate ameliorates oxidative stress-induced acute kidney injury after traumatic brain injury by activating Keap1-Nrf2/HO-1 signaling pathway

Acute kidney injury (AKI) frequently emerges as a consequential non-neurological sequel to traumatic brain injury (TBI), significantly contributing to heightened mortality risks. The intricate interplay of oxidative stress in the pathophysiology of TBI underscores the centrality of the Keap1-Nrf2/HO-1 signaling pathway as a pivotal regulator in this context. This study endeavors to elucidate the involvement of the Keap1-Nrf2/HO-1 pathway in modulating oxidative stress in AKI subsequent to TBI and concurrently explore the therapeutic efficacy of dimethyl fumarate (DMF). A rat model of TBI was established via the Feeney free-fall method, incorporating interventions with varying concentrations of DMF. Assessment of renal function ensued through measurements of serum creatinine and neutrophil gelatinase-associated lipocalin. Morphological evaluation of renal pathology was conducted employing quantitative hematoxylin and eosin staining. The inflammatory response was scrutinized by quantifying interleukin (IL)-6, IL-1β, and tumor necrosis factor-α levels. Oxidative stress levels were discerned through quantification of malondialdehyde and superoxide dismutase. The apoptotic cascade was examined via the terminal deoxynucleotidyl transferase dUTP deletion labeling assay. Western blotting provided insights into the expression dynamics of proteins affiliated with the Keap1-Nrf2/HO-1 pathway and apoptosis. The findings revealed severe kidney injury, heightened oxidative stress, inflammation, and apoptosis in the traumatic brain injury model. Treatment with DMF effectively reversed these changes, alleviating oxidative stress by activating the Keap1-Nrf2/HO-1 signaling pathway, ultimately conferring protection against AKI. Activating Keap1-Nrf2/HO-1 signaling pathway may be a potential therapeutic strategy for attenuating oxidative stress-induced AKI after TBI.

Excessive linoleic acid induces muscle oxidative stress through 5-lipoxygenase-dependent peroxidation

Oxidative stress in muscles is closely related to the occurrence of insulin resistance, muscle weakness and atrophy, age-related sarcopenia, and cancer. Aldehydes, a primary oxidation intermediate of polyunsaturated fatty acids, have been proven to be an important trigger for oxidative stress. However, the potential role of linoleic acid (LA) as a donor for volatile aldehydes to trigger oxidative stress has not been reported. Here, we reported that excessive dietary LA caused muscle redox imbalance and volatile aldehydes containing hexanal, 2-hexenal, and nonanal were the main metabolites leading to oxidative stress. Importantly, we identified 5-lipoxygenase (5-LOX) as a key enzyme mediating LA peroxidation in crustaceans for the first time. The inhibition of 5-LOX significantly suppressed the content of aldehydes produced by excessive LA. Mechanistically, the activation of the cyclic adenosine monophosphate (cAMP)-protein kinase A (PKA) pathway facilitated the translocation of 5-LOX from the nucleus to the cytoplasm, where 5-LOX oxidized LA, leading to oxidative stress through the generation of aldehydes. This study suggests that 5-LOX is a potential target to prevent the production of harmful aldehydes.

A mutation in LPAR2 activates the miR-939-5p-LPAR2-PI3K/AKT axis to regulate the proliferation and apoptosis of granulosa cells in sheep

Lysophosphatidic acid receptor-2 (LPAR2) is a G protein-coupled receptor, which is involved in various physiological processes such as cell development, proliferation, and apoptosis, and is thought to play an important role in follicular development and reproduction. There is evidence that miRNA recognition elements (MRE) in the gene 3'UTR often contain single nucleotide polymorphisms (SNPs) that can alter the binding affinity of the target miRNA, leading to dysregulation of gene expression. In this study, we detected a SNP in LPAR2 3 'UTR (rs410670692, c.*701C > T) in 384 small-tailed Han sheep using Sequenom MassARRAY®SNP genotyping. Association analysis showed that the SNP was significantly associated with litter size. Then, the effect of LPAR2 rs410670692 mutation on gene expression in sheep hosts was studied by molecular biotechnology. The results showed that the expression of LPAR2 in the TT genotype was significantly higher than that in the CC genotype, which confirmed the existence of rs410670692, a functional SNP, in LPAR2 3'UTR. We then used bioinformatics methods and double luciferase reporter gene assay to predict and confirm LPAR2 SNP rs410670692 as the direct targeting regulatory element of miR-939-5p. Cell transfection experiments further found that SNP rs410670692 down-regulated the mRNA and protein levels of LPAR2 by influencing the binding of miR-939-5p. To understand the function and mechanism of miR-939-5p in sheep granulosa cells (GCs), we conducted cell proliferation and apoptosis experiments which showed inhibited GCs proliferation along with promoted GCs apoptosis upon overexpression of miR-939-5p. Moreover, overexpression of miR-939-5p promotes apoptosis of granulosa cells by blocking the LPAR2-dependent PI3K/Akt signaling pathway. In conclusion, these results indicate that the SNP rs410670692 of LPAR2 is related to the litter size of small-tailed cold sheep, and miR-939-5p can act as a regulatory element binding to the C mutation of rs410670692 to regulate the expression of LPAR2, affect the development of GCs, and thus indirectly affect the litter size of sheep. These studies provide evidence for the involvement of LPAR2 polymorphism in sheep reproduction and are expected to provide new insights into the molecular genetic mechanisms of litter size traits in sheep.

Melatonin-Derived Carbon Dots with Free Radical Scavenging Property for Effective Periodontitis Treatment via the Nrf2/HO-1 Pathway

Periodontitis is a chronic inflammatory disease closely associated with reactive oxygen species (ROS) involvement. Eliminating ROS to control the periodontal microenvironment and alleviate the inflammatory response could potentially serve as an efficacious therapy for periodontitis. Melatonin (MT), renowned for its potent antioxidant and anti-inflammatory characteristics, is frequently employed as an ROS scavenger in inflammatory diseases. However, the therapeutic efficacy of MT remains unsatisfactory due to the low water solubility and poor bioavailability. Carbon dots have emerged as a promising and innovative nanomaterial with facile synthesis, environmental friendliness, and low cost. In this study, melatonin-derived carbon dots (MT-CDs) were successfully synthesized via the hydrothermal method. The MT-CDs have good water solubility and biocompatibility and feature excellent ROS-scavenging capacity without additional modification. The in vitro experiments proved that MT-CDs efficiently regulated intracellular ROS, which maintained mitochondrial homeostasis and suppressed the production of inflammatory mediators. Furthermore, findings from the mouse model of periodontitis indicated that MT-CDs significantly inhibited the deterioration of alveolar bone and reduced osteoclast activation and inflammation, thereby contributing to the regeneration of damaged tissue. In terms of the mechanism, MT-CDs may scavenge ROS, thereby preventing cellular damage and the production of inflammatory factors by regulating the nuclear factor erythroid 2-related factor 2 (Nrf2)/heme oxygenase-1 (HO-1) pathway. The findings will offer a vital understanding of the advancement of secure and effective ROS-scavenging platforms for more biomedical applications.

Co-exposure to polystyrene nanoplastics and triclosan induces synergistic cytotoxicity in human KGN granulosa cells by promoting reactive oxygen species accumulation

In recent years, nanoplastics (NPs) and triclosan (TCS, a pharmaceutical and personal care product) have emerged as environmental pollution issues, and their combined presence has raised widespread concern regarding potential risks to organisms. However, the combined toxicity and mechanisms of NPs and TCS remain unclear. In this study, we investigated the toxic effects of polystyrene NPs and TCS and their mechanisms on KGN cells, a human ovarian granulosa cell line. We exposed KGN cells to NPs (150 μg/mL) and TCS (15 μM) alone or together for 24 hours. Co-exposure significantly reduced cell viability. Compared with exposure to NPs or TCS alone, co-exposure increased reactive oxygen species (ROS) production. Interestingly, co-exposure to NPs and TCS produced synergistic effects. We examined the activity of superoxide dismutase (SOD) and catalase (CAT), two antioxidant enzymes; it was significantly decreased after co-exposure. We also noted an increase in the lipid oxidation product malondialdehyde (MDA) after co-exposure. Furthermore, co-exposure to NPs and TCS had a more detrimental effect on mitochondrial function than the individual treatments. Co-exposure activated the NRF2-KEAP1-HO-1 antioxidant stress pathway. Surprisingly, the expression of SESTRIN2, an antioxidant protein, was inhibited by co-exposure treatments. Co-exposure to NPs and TCS significantly increased the autophagy-related proteins LC3B-II and LC3B-Ⅰ and decreased P62. Moreover, co-exposure enhanced CASPASE-3 expression and inhibited the BCL-2/BAX ratio. In summary, our study revealed the synergistic toxic effects of NPs and TCS in vitro exposure. Our findings provide insight into the toxic mechanisms associated with co-exposure to NPs and TCS to KGN cells by inducing oxidative stress, activations of the NRF2-KEAP1-HO-1 pathway, autophagy, and apoptosis.

Maternal MicroRNA Profile Changes When LH Is Added to the Ovarian Stimulation Protocol: A Pilot Study

While the use of follicle-stimulating hormone (FSH) in ovarian stimulation for in vitro fertilization (IVF) is an established practice, the use of luteinizing hormone (LH) remains debatable. MicroRNAs (miRNAs) are short, endogenous, non-coding transcripts that control a variety of cellular functions, such as gonadotrophin production and follicular development. The goal of this pilot study was to investigate whether the employment of recombinant LH (rLH) in ovarian stimulation protocols results in changes in the miRNA profiles in human oocytes. Patients were divided into two groups: seven received recombinant FSH (rFSH, 225 IU), and six received rFSH (150 IU) plus rLH (75 IU). MiRNA predesigned panels and real-time PCR technology were used to analyze the oocytes retrieved from the follicular ovarian retrieval. Among the miRNAs evaluated, a series of them evidenced upregulation or downregulation in their expression in the FSH plus LH group compared to the FSH group. Considering the results obtained from the functional and network analysis, the different maternal miRNA profiles in the two groups revealed a differential modulation of pathways involved in numerous biological functions. Overall, based on the pathways associated with most of these maternal miRNAs, the presence of LH may result in a different modulation of pathways regulating survival under the control of a Tp53-related mechanism. Interestingly, among the miRNAs differentially expressed in oocytes of the two groups, we have found miRNAs already investigated at ovarian, follicular, oocyte, and embryonic levels: hsa-miR-484, hsa-miR-222, hsa-miR-520d-5p, hsa-miRNA-17, hsa-miR-548, and hsa-miR-140. Thus, investigation into the role of these miRNAs in oocyte molecular pathways may help determine how LH affects oocyte competence and eventually leads to the clinical improvement of IVF.