MicroRNA‐146b‐5p overexpression attenuates premature ovarian failure in mice by inhibiting the Dab2ip/Ask1/p38‐Mapk pathway and γH2A.X phosphorylation

Abstract

Objective: To examine the role of high-fat and high-sugar (HFHS) diet-induced oxidative stress, which is a risk factor for various diseases, in premature ovarian failure (POF). Materials and methods:Ovarian granulosa cells (OGCs) were isolated from mice and cultured in medium supplemented with HFHS and poly (lactic-co-glycolic acid) (PLGA)-cross-linked miR-146b-5p nanoparticles (miR-146@PLGA). RNA and protein expression levels were examined using quantitative real-time polymerase chain reaction and Western blotting, respectively. HFHS diet-induced POF model mice were administered miR-146@PLGA. Results: The ovarian tissue of mice fed a HFHS diet exhibited the typical pathological characteristics of POF. HFHS supplementation induced oxidative stress injury in the mouse OGCs, activation of the Dab2ip/Ask1/p38-Mapk signalling pathway and phosphorylation of γH2A.X in vitro and in vivo. The results of the luciferase reporter assay revealed that miR-146 specifically downregulated p38-Mapk14 expression. Meanwhile, co-immunoprecipitation and Western blot analyses revealed that HFHS supplementation upregulated nuclear p38-Mapk14 expression and consequently enhanced γH2A.X (Ser139) phosphorylation. The HFHS diet-induced POF mouse model treated with miR-146@PLGA exhibited downregulated p38-Mapk14 expression in the OGCs, mitigated OGC ageing and alleviated the symptoms of POF. Conclusions: This study demonstrated that HFHS supplementation activates the Dab2ip/Ask1/p38-Mapk signalling pathway and promotes γH2A.X phosphorylation by inhibiting the expression of endogenous miR-146b-5p, which results in OGC ageing and POF development.

Thymopentin alleviates premature ovarian failure in mice by activating YY2/Lin28A and inhibiting the expression of let‐7 family microRNAs

“…Our methods were performed according to previous reports 13,21‐23 . Briefly, YY2‐siRNA (siYY2) and random control (siMock) oligoRNAs were synthesized by GenePharma (GenePharma).…”

“…This model derives from prbeviously published methods. 7 , 13 , 19 , 20 Briefly, 10‐week‐old female C57BL/6 mice (n = 30) were purchased from the Experimental Animal Centre of the Shanghai University of Traditional Chinese Medicine. Mice were randomly allocated to three groups, with ten mice per group.…”

“…Our methods were performed according to previous reports. 13 , 21 , 22 , 23 Briefly, YY2‐siRNA (siYY2) and random control (siMock) oligoRNAs were synthesized by GenePharma (GenePharma). The PLGA (MedChemExpress) was dissolved overnight in methylene chloride, prior to siYY2/ siMOCK and spermidine complex formation using an 8:1 molar ratio of the polyamine nitrogen to nucleotide phosphate.…”

“… 1 We also reported epigenetic mechanisms of action subserving the dietary effects of HFHS, leading to ovarian granulosa cell ageing and premature ovarian failure by inhibiting endogenous miR‐146, activating the DAB2IP/ASK1/p38‐signalling pathway and inducing γ‐H2A.X phosphorylation modification. 13 All of these actions show that HFHS can elevate the risk for POF.…”

Qilin Pill Exerts Therapeutic Effect on Resection-Induced Premature Ovarian Insufficiency Rats by Inhibiting the MAPK and PI3K-AKT Signaling Pathways

“…The MAPK signaling pathway is involved in the regulation of cell proliferation, differentiation, and apoptosis, and the activation of MAPKs has recently been found to be associated with POI development. 44 , 47 The PI3K-AKT signaling pathway has a wide range of functions, and plays an important role in the regulation of follicle activation and the development of POI. 48–51 The hyperactivation of the PI3K-AKT signaling pathway will rapidly deplete the number of primordial follicles and result in POI.…”