Non-Esterified Fatty Acid-Induced Apoptosis in Bovine Granulosa Cells via ROS-Activated PI3K/AKT/FoxO1 Pathway

Elevated Linoleic Acid Intake Becomes a Risk Factor for Polycystic Ovary Syndrome by Affecting Ovarian Granulosa Cells

Polycystic ovary syndrome (PCOS) is one of the most common endocrine and metabolic disorders in females of reproductive age; this condition is particularly concerning due to its potential to cause infertility. Linoleic acid (LA) is an essential and widely consumed n-6 polyunsaturated fatty acid. In the past decades, LA intake has sharply surged, as recommended by dietary guidelines and advances in the food industry. An increasing number of people are questioning the health benefits of LA. In patients with PCOS, dietary management is crucial for improving symptoms to obtain good outcomes with assisted reproductive technology (ART). Diets rich in n-6 fatty acid has become "arch-criminal" of "silent inflammation." PCOS is also associated with low-grade chronic inflammation. Therefore, identification of the relationship between dietary LA and PCOS is urgently required. In this study, we first conducted experiments to observe the effects of different LA concentrations on PCOS-related phenotypes in mice. The results showed that medium and high concentrations of LA led to PCOS-like changes in mice, presenting with disordered estrous cycles, polycystic ovaries, and hyperandrogenism. LA is independent of PCOS-related weight gain and insulin resistance. LA caused systemic inflammation, reduced antioxidant capacity, and increased ovary apoptosis in mice. To explore how LA acts in vivo, we used the ovarian granulosa cell line KGN to detect alterations in the levels of granulosa cells (GCs). In addition to having no impact on endocrine function, LA can decrease the antioxidant capacity, reduce mitochondrial function, increase the apoptotic rate, and induce inflammation in GCs. To obtain more information, the pretreated GCs were subjected to transcriptome sequencing. The abundant RNA-Seq results make future directions for understanding the mechanism of LA action on GCs in PCOS more explicit. In summary, elevated LA intake is a risk factor for PCOS that affects ovarian GCs. Further studies should focus on establishing a strict intake range for the prevention and treatment of PCOS.

AMPKα alleviates the inhibitory effect of NEFA on the function of bovine follicular granulosa cells cultured in vitro

High levels of non-esterified fatty acids (NEFA) in cows with subclinical ketosis (SCK) impair postpartum follicular development and disrupt estrus. The precise mechanism through which NEFA impacts the functionality of bovine follicular cells remains elusive. An in vivo experiment was conducted to compare SCK cows without estrus (SCK-E, n = 6) with healthy cows in estrus (C-E, n = 6). In the vitro test, bovine granulosa cells (GCs) were exposed to 0.4 mM NEFA. Notably, the SCK-E group exhibited an elevated ratio of phosphorylated adenosine 5'-monophosphate-activated protein kinase α (AMPKα) to total AMPKα in both liver and ovarian tissues, compared to the C-E group. NEFA treatment of GCs adversely affected steroid hormone synthesis, suppressed the expression of cyclin and proteins crucial for steroid synthesis, and triggered cell apoptosis, thereby inhibiting cell proliferation. Furthermore, it led to a decline in cell mitochondrial membrane potential and an increase in reactive oxygen species production, ultimately causing cellular damage. Subsequently, GCs were co-cultured with adenovirus (ad-AMPKα-siRNA) and NEFA (0.4 mM). Inhibiting AMPKα further exacerbated the detrimental effects of NEFA on steroid hormone synthesis, cell apoptosis, cell proliferation, and mitochondrial function in GCs. Furthermore, upon inhibiting AMPKα, a reduction was observed in both mRNA and protein levels of acetyl-CoA carboxylase 1, accompanied by an elevation in the levels of carnitine palmitoyltransferase-1. These findings suggest that AMPKα becomes activated in SCK cows experiencing elevated NEFA levels, and that AMPKα has the potential to mitigate the detrimental effects of NEFA on GCs function in vitro.

Isorhamnetin Ameliorates Non-Esterified Fatty Acid-Induced Apoptosis, Lipid Accumulation, and Oxidative Stress in Bovine Endometrial Epithelial Cells via Inhibiting the MAPK Signaling Pathway

High concentrations of non-esterified fatty acids (NEFA) in the blood contribute to various metabolic disorders and are linked to endometritis in dairy cows. Isorhamnetin (ISO), a flavonoid found in many plants, is known for its antioxidant, anti-inflammatory, and anti-obesity properties. This study systematically assessed NEFA-induced damage in bovine endometrial epithelial cells (bEECs) and investigated whether ISO alleviates NEFA-induced cell damage and its underlying molecular mechanisms. Our observations revealed that excessive NEFA inhibited proliferation and induced apoptosis in bEECs, accompanied by an increase in the expression of BAX and cleaved caspase-3. We further observed that NEFA could induce lipid accumulation, reactive oxygen species (ROS) generation, and the release of pro-inflammatory factors IL-1β, IL-6, and TNF-α in bEECs. RNA sequencing and Western blot analysis revealed that NEFA induced damage in bEECs by activating MAPK signaling pathway. Notably, ISO treatment ameliorated these effects induced by NEFA, as evidenced by decreased protein levels of BAX, cleaved caspase-3, and PPAR-γ, along with reductions in triglyceride content, ROS generation, and levels of IL-1β, IL-6, and TNF-α. Mechanistically, our experimental results demonstrated that ISO inhibited NEFA-induced activation of MAPK signaling. Overall, ISO shows promise for therapeutic development to address NEFA-related endometritis in dairy cows.

The Phytochemical Profile of the Petroleum Ether Extract of Purslane Leaves and Its Anticancer Effect on 4-(Methylnitrosamino)-1-(3-pyridyl)-1-buta-4 None (NNK)-Induced Lung Cancer in Rats

Lung cancer is a prevalent and very aggressive sickness that will likely claim 1.8 million lives by 2022, with an estimated 2.2 million additional cases expected worldwide. The goal of the current investigation was to determine whether petroleum ether extract of purslane leaf could be used to treat lung cancer induced by 4-(Methylnitrosamino)-1-(3-pyridyl)-1-buta-4 none (NNK) in rats. In the in vitro extract recorded, promising anticancer effects in A540 cell lines with IC50 were close to the reference drug, doxorubicin (14.3 and 13.8 μg/mL, respectively). A dose of 500 mg/kg/day orally for 20 weeks exhibited recovery effects on NNK-induced lung cancer with a good safety margin, where Intercellular Adhesion Molecule-1 (ICAM-1), the lung cancer biomarker, was significantly reduced by about 18.75% compared to cancer control. Purslane exhibited many anticancer mechanisms, including (i) anti-proliferation as a significant reduction in Ki67 level (20.42%), (ii) anti-angiogenesis as evident by a considerable decrease in Matrix metalloproteinase-9 (MMP-9) expression (79%), (iii) anti-inflammation as a remarked decline in Insulin-like growth factor 1 (IGF-1) expression (62%), (iv) pro-apoptotic effect as a significant activation in Forkhead box protein O1 (FOXO1) expression (262%), and (v) anti-oxidation as remarkable activation on antioxidant biomarkers either non-enzymatic or enzymatic concurrent with considerable depletion on oxidative stress biomarker, in comparison to cancer control. The histopathological examination revealed that Purslane extract showed markedly improved tissue structure and reduced pathological changes across all examined organs caused by NNK. The anti-lung cancer effect exhibited by the extract may be linked to the active ingredients of the extract that were characterized by LC-MS, such as α-linolenic acid, linoleic acid, palmitic acid, β-sitosterol, and alkaloids (berberine and magnoflorine).

Elevated RBP4 in Subclinical Ketosis Cows Inhibits Follicular Granulosa Cell Proliferation and Steroid Hormone Synthesis

The mechanism by which subclinical ketosis (SCK) causes postpartum reproductive disorders in dairy cows remains unclear. In this study, cows within the day 14 to 21 postpartum period were categorized into the SCK group or the control group. Subsequently, they were monitored until 45 d to 60 d postpartum and divided into the SCK anestrus group (SCK-AE, n = 12) and the control estrus group (C-E, n = 12). In comparison to the C-E group, the RBP4 and p-AKT of the SCK-AE group exhibited increased levels in serum, liver, and ovaries. In the in vitro experimental cultivation of granulosa cells (GCs), after adding RBP4, cell proliferation, steroid hormone secretion and synthesis, and GLUT4 secretion were inhibited, and cell apoptosis was exacerbated. After silencing STRA6 (RBP4 receptor), cell proliferation and steroid hormone secretion and synthesis, as well as the inhibition of GLUT4, were alleviated, and the situation of cell apoptosis also improved. The SC79 activator could promote the phosphorylation of AKT, thus alleviating the increased cell proliferation, steroid hormone secretion and synthesis, GLUT4 inhibition, and apoptosis rate in cow GCs induced by RBP4 stimulation. Our research indicates that elevated RBP4 levels in SCK cows inhibit the proliferation, apoptosis, and steroid hormone synthesis of GCs through the STRA6 receptor and the PI3K/AKT pathway.

Exploring the impact of lipid droplets on the evolution and progress of hepatocarcinoma

Over the past 10 years, the biological role of lipid droplets (LDs) has gained significant attention in the context of both physiological and pathological conditions. Considerable progress has been made in elucidating key aspects of these organelles, yet much remains to be accomplished to fully comprehend the myriad functions they serve in the progression of hepatic tumors. Our current perception is that LDs are complex and active structures managed by a distinct set of cellular processes. This understanding represents a significant paradigm shift from earlier perspectives. In this review, we aim to recapitulate the function of LDs within the liver, highlighting their pivotal role in the pathogenesis of metabolic dysfunction-associated steatotic liver disease (MASLD) (Hsu and Loomba, 2024) and their contribution to the progression towards more advanced pathological stages up to hepatocellular carcinoma (HC) (Farese and Walther, 2009). We are aware of the molecular complexity and changes occurring in the neoplastic evolution of the liver. Our attempt, however, is to summarize the most important and recent roles of LDs across both healthy and all pathological liver states, up to hepatocarcinoma. For more detailed insights, we direct readers to some of the many excellent reviews already available in the literature (Gluchowski et al., 2017; Hu et al., 2020; Seebacher et al., 2020; Paul et al., 2022).

Comparative Metabolomic Profiling of L-Histidine and NEFA Treatments in Bovine Mammary Epithelial Cells

Non-esterified fatty acids (NEFAs) are pivotal in energy metabolism, yet high concentrations can lead to ketosis, a common metabolic disorder in cattle. Our laboratory observed lower levels of L-histidine in cattle suffering from ketosis, indicating a potential interaction between L-histidine and NEFA metabolism. This relationship prompted us to investigate the metabolomic alterations in bovine mammary epithelial cells (BMECs) induced by elevated NEFA levels and to explore L-histidine's potential mitigating effects. Our untargeted metabolomic analysis revealed 893 and 160 metabolite changes in positive and negative models, respectively, with VIP scores greater than 1 and p-values below 0.05. Notable metabolites like 9,10-epoxy-12-octadecenoic acid were upregulated, while 9-Ethylguanine was downregulated. A pathway analysis suggested disruptions in fatty acid and steroid biosynthesis pathways. Furthermore, L-histidine treatment altered 61 metabolites in the positive model and 34 in the negative model, with implications for similar pathways affected by NEFA. Overlaying differential metabolites from both conditions uncovered a potential key mediator, 1-Linoleoylglycerophosphocholine, which was regulated in opposite directions by NEFA and L-histidine. Our study uncovered that both NEFA L- and histidine metabolomics analyses pinpoint similar lipid biosynthesis pathways, with 1-Linoleoylglycerophosphocholine emerging as a potential key metabolite mediating their interaction, a discovery that may offer insights for therapeutic strategies in metabolic diseases.

N-Acetylcysteine Alleviates D-Galactose-Induced Injury of Ovarian Granulosa Cells in Female Rabbits by Regulating the PI3K/Akt/mTOR Signaling Pathway

The ovary plays a crucial role in the reproductive system of female animals. Ovarian problems such as ovarian insufficiency, premature aging, polycystic ovary syndrome, and ovarian cysts may lead to ovulation disorders, abnormal hormone secretion, or luteal dysfunction, thereby increasing the risk of infertility and abortion. Only when the ovarian function and other organs in the reproductive system remain healthy and work normally can female animals be ensured to carry out reproductive activities regularly, improve the pregnancy rate and litter size, promote the healthy development of the fetus, and then improve their economic value. The follicle, as the functional unit of the ovary, is composed of theca cells, granulosa cells (GCs), and oocytes. GCs are the largest cell population and main functional unit in follicles and provide the necessary nutrients for the growth and development of follicles. N-acetylcysteine (NAC) is a prevalent and cell-permeable antioxidant molecule that effectively prevents apoptosis and promotes cellular survival. Over the past few years, its function in boosting reproductive performance in animals at the cellular level has been widely acknowledged. However, its specific role and mechanism in influencing GCs is yet to be fully understood. The objective of this study was to examine the effects of NAC on ovarian damage in female rabbits. For this purpose, D-galactose (D-gal) was first used to establish a model of damaged GCs, with exposure to 1.5 mg/mL of D-gal leading to substantial damage. Subsequently, varying concentrations of NAC were introduced to determine the precise mechanism through which it influences cell damage. Based on the results of the Cell Counting Kit-8 assay, flow cytometry, and Western blotting, it was found that 0.5 mg/mL of NAC could significantly suppress cell apoptosis and promote proliferation. In particular, it decreased the expression levels of Bax, p53, and Caspase-9 genes, while concurrently upregulating the expression of the BCL-2 gene. Moreover, NAC was found to alleviate intracellular oxidative stress, suppress the discharge of mitochondrial Cytochrome c, and boost the enzymatic activities of CAT (Catalase), GSH (Glutathione), and SOD (Superoxide dismutase). RNA sequencing analysis subsequently underscored the critical role of the PI3K/Akt/mTOR pathway in governing proliferation and apoptosis within GCs. These findings demonstrated that NAC could significantly influence gene expression within this pathway, thereby clarifying the exact relationship between the PI3K/Akt/mTOR signaling cascade and the underlying cellular processes controlling proliferation and apoptosis. In conclusion, NAC can reduce the expression of Bax, p53, and Caspase-9 genes, inhibit the apoptosis of GCs, improve cell viability, and resist D-gal-induced oxidative stress by increasing the activity of CAT, GSH, and SOD. The molecular mechanism of NAC in alleviating D-gal-induced ovarian GC injury in female rabbits by regulating the PI3K/Akt/mTOR signaling pathway provides experimental evidence for the effect of NAC on animal reproductive function at the cellular level.

Linoleic acid induces human ovarian granulosa cell inflammation and apoptosis through the ER-FOXO1-ROS-NFκB pathway

Polycystic ovary syndrome (PCOS) is a complex reproductive endocrinological disorder influenced by a combination of genetic and environmental factors. Linoleic acid (LA) is a widely consumed ω-6 polyunsaturated fatty acid, accounting for approximately 80% of daily fatty acid intake. Building upon the prior investigations of our team, which established a connection between LA levels in the follicular fluid and PCOS, this study deeply examined the specific impact of LA using a granulosa cell line. Our findings revealed that LA exerts its influence on granulosa cells (GCs) by binding to the estrogen receptor (ER). Activated ER triggers the transcription of the FOXO1 gene. Reactive oxygen species (ROS)-related oxidative stress (OS) and inflammation occur downstream of LA-induced FOXO1 activation. Increased OS and inflammation ultimately culminate in GC apoptosis. In summary, LA modulates the apoptosis and inflammation phenotypes of GCs through the ER-FOXO1-ROS-NF-κB pathway. Our study provides additional experimental evidence to comprehend the pathophysiology of PCOS and provides novel insights into the dietary management of individuals with PCOS.

Resveratrol Promotes Proliferation, Antioxidant Properties, and Progesterone Production in Yak (Bos grunniens) Granulosa Cells

Resveratrol (RES) is a class of natural polyphenolic compounds known for its strong anti-apoptotic and antioxidant properties. Granulosa cells (GCs) are one of the important components of ovarian follicles and play crucial roles in follicular development of follicles in the ovary. Here, we explored the effects of RES on the proliferation and functions of yak GCs. Firstly, we evaluated the effect of RES dose and time in culture on the viability of GCs, and then the optimum treatment protocol (10 μM RES, 36 h) was selected to analyze the effects of RES on the proliferation, cell cycle, apoptosis, malondialdehyde (MDA), glutathione (GSH), reactive oxygen species (ROS) accumulation, lipid droplet content, ATP production, and steroidogenesis of GCs, as well as the expression of related genes. The results show that RES treatment significantly (1) increased cell viability and proliferation and inhibited cell apoptosis by upregulating BCL-2 and SIRT1 genes and downregulating BAX, CASP3, P53, and KU70 genes; (2) increased the proportion of GCs in the S phase and upregulated CCND1, PCNA, CDK4, and CDK5 genes; (3) reduced ROS accumulation and MDA content and increased GSH content, as well as upregulating the relative expression levels of CAT, SOD2, and GPX1 genes; (4) decreased lipid droplet content and increased ATP production; (5) promoted progesterone (P4) secretion and the expression of P4 synthesis-related genes (StAR, HSD3B1, and CYP11A1); and (6) inhibited E2 secretion and CYP19A1 expression. These findings suggest that RES at 10 μM increases the proliferation and antioxidant properties, inhibits apoptosis, and promotes ATP production, lipid droplet consumption, and P4 secretion of yak GCs.

FOXO1, a tiny protein with intricate interactions: Promising therapeutic candidate in lung cancer

Nowadays, lung cancer is the most common cause of cancer-related deaths in both men and women globally. Despite the development of extremely efficient targeted agents, lung cancer progression and drug resistance remain serious clinical issues. Increasing knowledge of the molecular mechanisms underlying progression and drug resistance will enable the development of novel therapeutic methods. It has been revealed that transcription factors (TF) dysregulation, which results in considerable expression modifications of genes, is a generally prevalent phenomenon regarding human malignancies. The forkhead box O1 (FOXO1), a member of the forkhead transcription factor family with crucial roles in cell fate decisions, is suggested to play a pivotal role as a tumor suppressor in a variety of malignancies, especially in lung cancer. FOXO1 is involved in diverse cellular processes and also has clinical significance consisting of cell cycle arrest, apoptosis, DNA repair, oxidative stress, cancer prevention, treatment, and chemo/radioresistance. Based on the critical role of FOXO1, this transcription factor appears to be an appropriate target for future drug discovery in lung cancers. This review focused on the signaling pathways, and molecular mechanisms involved in FOXO1 regulation in lung cancer. We also discuss pharmacological compounds that are currently being administered for lung cancer treatment by affecting FOXO1 and also point out the essential role of FOXO1 in drug resistance. Future preclinical research should assess combination drug strategies to stimulate FOXO1 and its upstream regulators as potential strategies to treat resistant or advanced lung cancers.

Advances in Research on Type 2 Diabetes Mellitus Targets and Therapeutic Agents

Diabetes mellitus is a chronic multifaceted disease with multiple potential complications, the treatment of which can only delay and prolong the terminal stage of the disease, i.e., type 2 diabetes mellitus (T2DM). The World Health Organization predicts that diabetes will be the seventh leading cause of death by 2030. Although many antidiabetic medicines have been successfully developed in recent years, such as GLP-1 receptor agonists and SGLT-2 inhibitors, single-target drugs are gradually failing to meet the therapeutic requirements owing to the individual variability, diversity of pathogenesis, and organismal resistance. Therefore, there remains a need to investigate the pathogenesis of T2DM in more depth, identify multiple therapeutic targets, and provide improved glycemic control solutions. This review presents an overview of the mechanisms of action and the development of the latest therapeutic agents targeting T2DM in recent years. It also discusses emerging target-based therapies and new potential therapeutic targets that have emerged within the last three years. The aim of our review is to provide a theoretical basis for further advancement in targeted therapies for T2DM.