M(6)A demethylase FTO-stabilized exosomal circBRCA1 alleviates oxidative stress-induced granulosa cell damage via the miR-642a-5p/FOXO1 axis.

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. 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. 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. 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.

Zhu X ，Li W ，Lu M ，Shang J ，Zhou J ，Lin L ，Liu Y ，Xing J ，Zhang M ，Zhao S ，Lu J ，Shi X ... -  《JOURNAL OF NANOBIOTECHNOLOGY》

Improving Granulosa Cell Function in Premature Ovarian Failure with Umbilical Cord Mesenchymal Stromal Cell Exosome-Derived hsa_circ_0002021.

The therapeutic potential of exosomes from human umbilical cord mesenchymal stem cells (HUMSCs-Exo) for delivering specific circular RNAs (circRNAs) in treating premature ovarian failure (POF) is not well understood. This study aimed to explore the efficacy of HUMSCs-Exo in delivering hsa_circ_0002021 for POF treatment, focusing on its effects on granulosa cell (GC) senescence and ovarian function. Bioinformatic analysis was conducted on circRNA profiles using the GSE97193 dataset from GEO, targeting granulosa cells from varied age groups. To simulate granulosa cell senescence, KGN cells were treated with cyclophosphamide (CTX). HUMSCs were transfected with pcDNA 3.1 vectors to overexpress hsa_circ_0002021, and the HUMSCs-Exo secreted were isolated. These exosomes were characterized by transmission electron microscopy (TEM) and Western blotting to confirm exosomal markers CD9 and CD63. Co-culture of these exosomes with CTX-treated KGN cells was performed to assess β-galactosidase activity, oxidative stress markers, ROS levels, and apoptosis via flow cytometry. Interaction between hsa_circ_0002021, microRNA-125a-5p (miR-125a-5p), and cyclin-dependent kinase 6 (CDK6) was investigated using dual-luciferase assays and RNA immunoprecipitation (RIP). A POF mouse model was induced with CTX, treated with HUMSCs-Exo, and analyzed histologically and via immunofluorescence staining. Gene expression was quantified using RT-qPCR and Western blot. hsa_circ_0002021 was under expressed in both in vivo and in vitro POF models and was effectively delivered by HUMSCs-Exo to KGN cells, showing a capability to reduce GC senescence. Overexpression of hsa_circ_0002021 in HUMSCs-Exo significantly enhanced these anti-senescence effects. This circRNA acts as a competitive adsorbent of miR-125a-5p, regulating CDK6 expression, which is crucial in modulating cell cycle and apoptosis. Enhanced expression of hsa_circ_0002021 in HUMSCs-Exo ameliorated GC senescence in vitro and improved ovarian function in POF models by modulating oxidative stress and cellular senescence markers. This study confirms that hsa_circ_0002021, when delivered through HUMSCs-Exo, can significantly mitigate GC senescence and restore ovarian function in POF models. These findings provide new insights into the molecular mechanisms of POF and highlight the therapeutic potential of circRNA-enriched exosomes in treating ovarian aging and dysfunction.

Yang G ，Zhang B ，Xu M ，Wu M ，Lin J ，Luo Z ，Chen Y ，Hu Q ，Huang G ，Hu H ... -  《-》

Human umbilical cord mesenchymal stem cell-derived extracellular vesicles improve ovarian function in rats with primary ovarian insufficiency by carrying miR-145-5p.

Stem cell/exosome therapy is a novel strategy for primary ovarian insufficiency (POI). This paper is to examine the role of human umbilical cord mesenchymal stem cell-derived extracellular vesicles (hUCMSC-EVs) in POI. hUCMSC-EVs were extracted and identified. POI rats were induced by cyclophosphamide for 15 days and treated with EV or GW4869 every 5 days and euthanized 28 days later. Vaginal smears were observed for 21 days. Serum hormone levels (FSH/E2/AMH) were measured by ELISA. Ovarian morphology, follicle numbers, and granulosa cell (GC) apoptosis were observed by HE and TUNEL staining. GCs extracted from Swiss albino rats were cyclophosphamide-induced to establish the POI cell model, followed by oxidative injury and apoptosis evaluation with the help of DCF-DA fluorescence, ELISA, and flow cytometry. The relation between miR-145-5p and XBP1 was predicted on StarBase and validated by dual-luciferase assay. miR-145-5p and XBP1 levels were measured by RT-qPCR and Western blot. EV treatment reduced irregular estrus cycle incidence since day 7, increased E2 and AMH levels and all-stage follicle numbers, reduced FSH level, GC apoptosis, and atretic follicle numbers in POI rats. EV treatment diminished GC oxidative injury and apoptosis in vitro. miR-145-5p knockdown in hUCMSC-EVs partly abolished hUCMSC-EV-mediated effects on GCs and ovarian function in vivo and on GC oxidative injury and apoptosis in vitro. Silencing XBP1 partially negated miR-145-5p knockdown-exerted effects on GCs in vitro. miR-145-5p carried by hUCMSC-EVs attenuates GC oxidative injury and apoptosis and thus extenuates ovarian injury and improves ovarian function in POI rats.

Lu Y ，Wei Y ，Shen X ，Tong Y ，Lu J ，Zhang Y ，Ma Y ，Zhang R ... -  《-》

Exosomal miRNA-17-5p derived from human umbilical cord mesenchymal stem cells improves ovarian function in premature ovarian insufficiency by regulating SIRT7.

Premature ovarian insufficiency (POI) is clinically irreversible in women aged over 40 years. Although numerous studies have demonstrated satisfactory outcomes of mesenchymal stem cell therapy, the underlying therapeutic mechanism remains unclear. Exosomes were collected from the culture medium of human umbilical cord mesenchymal stem cells (hUMSCs) and assessed by electron microscopy and Western blot (WB) analysis. Then, exosomes were added to the culture medium of cyclophosphamide (CTX)-damaged human granulosa cells (hGCs), and the mixture was injected into the ovaries of CTX-induced POI model mice before detection of antiapoptotic and apoptotic gene expression. Next, the microRNA expression profiles of hUMSC-derived exosomes (hUMSC-Exos) were detected by small RNA sequencing. The ameliorative effect of exosomal microRNA-17-5P (miR-17-5P) was demonstrated by miR-17-5P knockdown before assessment of ovarian phenotype and function, reactive oxygen species (ROS) levels and SIRT7 expression. Finally, SIRT7 was inhibited or overexpressed by RNA interference or retrovirus transduction, and the protein expression of PARP1, γH2AX, and XRCC6 was analyzed. The ameliorative effect of hUMSC-Exos on POI was validated. Our results illustrated that hUMSC-Exos restored ovarian phenotype and function in a POI mouse model, promoted proliferation of CTX-damaged hGCs and ovarian cells, and alleviated ROS accumulation by delivering exosomal miR-17-5P and inhibiting SIRT7 expression. Moreover, our findings elucidated that miR-17-5P repressed PARP1, γH2AX, and XRCC6 by inhibiting SIRT7. Our findings suggest a critical role for exosomal miR-17-5P and its downstream target mRNA SIRT7 in hUMSC transplantation therapy. This study indicates the promise of exosome-based therapy for POI treatment.

Ding C ，Zhu L ，Shen H ，Lu J ，Zou Q ，Huang C ，Li H ，Huang B ... -  《-》

Bu-Shen-Ning-Xin decoction ameliorates premature ovarian insufficiency by suppressing oxidative stress through rno_circRNA_012284/rno_miR-760-3p/HBEGF pathway.

POI (premature ovarian insufficiency) refers to premature and rapid decline of ovarian reserve function in women before the age of 40, which can be manifested as menstrual disorders, endocrine abnormalities and low fertility. Bu-Shen-Ning-Xin decoction (BSNXD) has been found to have therapeutic effects on POI. Nevertheless, how it exerts therapeutic effects remains elusive. This research aims to clarify the pharmacological mechanisms of BSNXD. We applied Ultra Performance Liquid Chromatography (UPLC) to identify the main components of BSNXD.4-vinylcyclohexene diepoxide(VCD)was used to induce POI models. ELISA detected the serum level of hormones. H&E staining evaluated the morphology of ovarian tissues.CircRNA and mRNA expression profiles in the ovaries of both POI rats and those treated with BSNXD were detected. Then, dysregulated circRNAs and mRNAs that were potentially altered by BSNXD were screened. Network pharmacology analysis was performed to identify drug targets of BSNXD active ingredients. A circRNA-miRNA-mRNA network and an oxidative stress(OS)-related subnetwork were constructed. Expression of rno_circRNA_012284, rno_miR-760-3p, and HBEGF(Heparin-binding epidermal growth factor-like growth factor) was measured by RT-PCR and their binding were verified by dual-luciferase reporter assays. ROS was measured through DCFH-DA fluorescence probes. The HBEGF target was selected for molecular docking with key active ingredients.Surface plasmon resonance(SPR) was applied to verify the binding ability and affinity between components and HBEGF. UPLC analysis indicated that 6 chemical compounds including berberine, paeoniflorin, morroniside,gallic acid, loganin, baicalin were identified.Elevated FSH and LH levels, suppressed E2 and AMH levels in the serum, and inhibited follicles and corpus luteums in the ovarian tissues of VCD-induced rats were notably reversed by BSNXD.In total, 992 up- and 1135 down-regulated circRNAs, and 205 up- and 243 down-regulated mRNAs were found in POI rat ovaries following BSNXD administration. Furthermore, 198 drug targets of BSNXD were identified. An OS-related and BSNXD-targeted ceRNA subnetwork composed of rno_circRNA_012284/rno_miR-760-3p/HBEGF was established. rno_circRNA_012284 and HBEGF were up-regulated and rno_miR-760-3p was down-regulated in POI ovarian granulosa cells (OGCs) after BSNXD administration. rno_circRNA_012284 was a sponge of rno_miR-760-3p to elevate HBEGF expression. Moreover, rno_circRNA_012284 overexpression alleviated POI-induced excessive ROS generation in ovarian granulosa cells, while rno_circRNA_012284 inhibition exerted the opposite effect. Finally,molecular docking speculated active ingredients of each herb acted on HBEGF to reduce the OS. SPR tests showed that Berberine,Baicalein,Quercetin,Pachymic acid,Paeoniflorin exhibited satisfying affinity with HBEGF protein. This study demonstrates that BSNXD ameliorates POI partly by attenuating OS in ovarian granulosa cells via rno_circRNA_012284/rno_miR-760-3p/HBEGF axis, uncovering the pharmacological mechanisms of BSNXD in alleviating POI.

Xu X ，Wang J ，Jin X ，Ma Q ，Li H ，Zhou Q ，Chen W ... -  《-》