LncRNA SNHG5 adversely governs follicular growth in PCOS via miR-92a-3p/CDKN1C axis.

Small nucleolar RNA host genes (SNHGs) have been implicated in various biological processes, yet their involvement in polycystic ovary syndrome (PCOS) remains elusive. Specifically, SNHG5, a long non-coding RNA implicated in several human cancers, shows elevated expression in granulosa cells (GCs) of PCOS women and induces PCOS-like features when overexpressed in mice. In vitro, SNHG5 inhibits GC proliferation and induces apoptosis and cell-cycle arrest at G0/G1 phase, with RNA-seq indicating its impact on DNA replication and repair pathways. Mechanistically, SNHG5 acts as a competing endogenous RNA by binding to miR-92a-3p, leading to increased expression of target gene CDKN1C, which further suppresses GC proliferation and promotes apoptosis. These findings elucidate the crucial role of SNHG5 in the pathogenesis of PCOS and suggest a potential therapeutic target for this condition. Additional investigations such as large-scale clinical studies and functional assays are warranted to validate and expand upon these findings.

NLRP3 Inflammasome-dependent Pathway is Involved in the Pathogenesis of Polycystic Ovary Syndrome.

Accumulating evidence has shown that inflammation is a key process in polycystic ovary syndrome (PCOS). Nucleotide-binding oligomerization domain-, leucine-rich repeat-, and pyrin domain-containing 3 (NLRP3) inflammasomes play an essential role in inflammation. We investigated the expression of NLRP3 inflammasome in PCOS and its underlying mechanisms. Human granulosa cells (GCs) were isolated from patients with PCOS and control women who underwent in vitro fertilization and embryo transfer. Ovarian specimens were collected from mice with polycystic ovarian changes induced by a high-fat diet and letrozole. RNA sequencing (RNA-Seq) was performed on a granulosa cell line (KGN) overexpressing NLRP3. Polymerase chain reaction (PCR) was performed to quantify the differentially expressed genes of interest. NLRP3 and caspase-1 expression was significantly higher in GCs from patients with PCOS than in GCs from the control group. Increased NLRP3 and caspase-1 expression was also detected by immunohistochemistry in the GCs of a mouse model of polycystic ovarian changes. The serum IL-18 concentration in PCOS-like mice was significantly higher than that in control mice. Following NLRP3 overexpression in KGN cells, the genes involved in N-glycan processing, steroidogenesis, oocyte maturation, autophagy, and apoptosis were upregulated. The RT-qPCR results revealed that the expression levels of GANAB, ALG-5, HSD3B2, ULK1, PTK2B, and Casp7 in KGN cells after NLRP3 overexpression were significantly higher than those in control cells, which was consistent with the RNA-Seq results. Taken together, the NLRP3 inflammasome-dependent pathway is involved in the pathogenesis of PCOS not only by mediating pyroptosis, but also by regulating glycan synthesis, sex hormone synthesis, autophagy, and apoptosis in GCs.

Amylin receptor insensitivity impairs hypothalamic POMC neuron differentiation in the male offspring of maternal high-fat diet-fed mice.

OBJECTIVE: Amylin was found to regulate glucose and lipid metabolism by acting on the arcuate nucleus of the hypothalamus (ARC). Maternal high-fat diet (HFD) induces sex-specific metabolic diseases mediated by the ARC in offspring. This study was performed to explore 1) the effect of maternal HFD-induced alterations in amylin on the differentiation of hypothalamic neurons and metabolic disorders in male offspring and 2) the specific molecular mechanism underlying the regulation of amylin and its receptor in response to maternal HFD. METHODS: Maternal HFD and gestational hyper-amylin mice models were established to explore the role of hypothalamic amylin and receptor activity-modifying protein 3 (Ramp3) in regulating offspring metabolism. RNA pull-down, mass spectrometry, RNA immunoprecipitation, and RNA decay assays were performed to investigate the mechanism underlying the influence of maternal HFD on Ramp3 deficiency in the fetal hypothalamus. RESULTS: Male offspring with maternal HFD grew heavier and developed metabolic disorders, whereas female offspring with maternal HFD showed a slight increase in body weight and did not develop metabolic disorders compared to those exposed to maternal normal chow diet (NCD). Male offspring exposed to a maternal HFD had hyperamylinemia from birth until adulthood, which was inconsistent with offspring exposed to maternal NCD. Hyperamylinemia in the maternal HFD-exposed male offspring might be attributed to amylin accumulation following Ramp3 deficiency in the fetal hypothalamus. After Ramp3 knockdown in hypothalamic neural stem cells (htNSCs), amylin was found to fail to promote the differentiation of anorexigenic alpha-melanocyte-stimulating hormone-proopiomelanocortin (α-MSH-POMC) neurons but not orexigenic agouti-related protein-neuropeptide Y (AgRP-Npy) neurons. An investigation of the mechanism involved showed that IGF2BP1 could specifically bind to Ramp3 in htNSCs and maintain its mRNA stability. Downregulation of IGF2BP1 in htNSCs in the HFD group could decrease Ramp3 expression and lead to an impairment of α-MSH-POMC neuron differentiation. CONCLUSIONS: These findings suggest that gestational exposure to HFD decreases the expression of IGF2BP1 in the hypothalami of male offspring and destabilizes Ramp3 mRNA, which leads to amylin resistance. The subsequent impairment of POMC neuron differentiation induces sex-specific metabolic disorders in adulthood.

Novel PGK1 determines SKP2-dependent AR stability and reprograms granular cell glucose metabolism facilitating ovulation dysfunction.

BACKGROUND: Disordered folliculogenesis is a core characteristic of polycystic ovary syndrome (PCOS) and androgen receptors (ARs) are closely associated with hyperandrogenism and abnormalities in folliculogenesis in PCOS. However, whether the new AR binding partner phosphoglycerate kinase 1 (PGK1) in granulosa cells (GCs) plays a key role in the pathogenesis of PCOS remains unclear. METHODS: We identified the new AR binding partner PGK1 by co-IP (co-immunoprecipitation) in luteinized GCs, and reconfirmed by co-IP, co-localization and GST pull down assay, and checked PGK1 expression levels with qRT-PCR and western blotting. Pharmaceuticals rescue assays in mice, and metabolism assay, AR protein stability and RNA-seq of PGK1 targets in cells proved the function in PCOS. FINDINGS: PGK1 and AR are highly expressed in PCOS luteinized GCs and PCOS-like mouse ovarian tissues. PGK1 regulated glucose metabolism and deteriorated PCOS-like mouse metabolic disorder, and paclitaxel rescued the phenotype of PCOS-like mice and reduced ovarian PGK1 and AR protein levels. PGK1 inhibited AR ubiquitination levels and increased AR stability in an E3 ligase SKP2-dependent manner. Additionally, PGK1 promoted AR nuclear translocation, and RNA-seq data showed that critical ovulation-related genes were regulated by the PGK1-AR axis. INTERPRETATION: PGK1 regulated GCs metabolism and interacted with AR to regulate the expression of key ovulation genes, and also mediated cell proliferation and apoptosis, which resulted in the etiology of PCOS. This work highlights the pathogenic mechanism and represents a novel therapeutic target for PCOS. FUNDING: National Key Research and Development Program of China; National Natural Science Foundation of China grant.

Elicitor hydrophobin Hyd1 interacts with Ubiquilin1-like to induce maize systemic resistance.

Trichoderma harzianum is a plant-beneficial fungus that secretes small cysteine-rich proteins that induce plant defense responses; however, the molecular mechanism involved in this induction is largely unknown. Here, we report that the class II hydrophobin ThHyd1 acts as an elicitor of induced systemic resistance (ISR) in plants. Immunogold labeling and immunofluorescence revealed ThHyd1 localized on maize (Zea mays) root cell plasma membranes. To identify host plant protein interactors of Hyd1, we screened a maize B73 root cDNA library. ThHyd1 interacted directly with ubiquilin 1-like (UBL). Furthermore, the N-terminal fragment of UBL was primarily responsible for binding with Hyd1 and the eight-cysteine amino acid of Hyd1 participated in the protein-protein interactions. Hyd1 from T. harzianum (Thhyd1) and ubl from maize were co-expressed in Arabidopsis thaliana, they synergistically promoted plant resistance against Botrytis cinerea. RNA-sequencing analysis of global gene expression in maize leaves 24 h after spraying with Curvularia lunata spore suspension showed that Thhyd1-induced systemic resistance was primarily associated with brassinosteroid signaling, likely mediated through BAK1. Jasmonate/ethylene (JA/ET) signaling was also involved to some extent in this response. Our results suggest that the Hyd1-UBL axis might play a key role in inducing systemic resistance as a result of Trichoderma-plant interactions.

Identification of a novel fungus, Trichoderma asperellum GDFS1009, and comprehensive evaluation of its biocontrol efficacy.

Due to its efficient broad-spectrum antimicrobial activity, Trichoderma has been established as an internationally recognized biocontrol fungus. In this study, we found and identified a novel strain of Trichoderma asperellum, named GDFS1009. The mycelium of T. asperellum GDFS1009 exhibits a high growth rate, high sporulation capacity, and strong inhibitory effects against pathogens that cause cucumber fusarium wilt and corn stalk rot. T. asperellum GDFS1009 secretes chitinase, glucanase, and protease, which can degrade the cell walls of fungi and contribute to mycoparasitism. The secreted xylanases are good candidates for inducing plant resistance and enhancing plant immunity against pathogens. RNA sequencing (RNA-seq) and gas chromatography-mass spectrometry (GC-MS) showed that T. asperellum GDFS1009 produces primary metabolites that are precursors of antimicrobial compounds; it also produces a variety of antimicrobial secondary metabolites, including polyketides and alkanes. In addition, this study speculated the presence of six antimicrobial peptides via ultra-performance liquid chromatography quadrupole time of flight mass spectrometry (UPLC-QTOF-MS/MS). Future studies should focus on these antimicrobial metabolites for facilitating widespread application in the field of agricultural bio-control.