Apocynin Dietary Supplementation Delays Mouse Ovarian Ageing

Abstract

Advanced maternal age is associated with higher infertility rates, pregnancy-associated complications, and progeny health issues. The ovary is considered the main responsible for these consequences due to a continuous decay in follicle number and oocyte quality. Intracellular imbalance between oxidant molecules and antioxidant mechanisms, in favour of the former, results in oxidative stress (OS) that is believed to contribute to ovarian ageing. This work is aimed at evaluating whether an age-related increase in ovarian OS, inflammation, and fibrosis may contribute to tissue dysfunction and whether specific antioxidant supplementation with a NADPH oxidase inhibitor (apocynin) could ameliorate them. Mice aged 8–12 weeks (reproductively young) or 38-42 weeks (reproductively aged) were employed. Aged mice were divided into two groups, with one receiving apocynin (5 mM) in the drinking water, for 7 weeks, upon which animals were sacrificed and their ovaries collected. Ovarian structure was similar at both ages, but the ovaries from reproductively aged mice exhibited lipofuscin deposition, enhanced fibrosis, and a significant age-related reduction in primordial and primary follicle number when compared to younger animals. Protein carbonylation and nitration, and markers of OS were significantly increased with age. Moreover, mRNA levels of inflammation markers, collagens, metalloproteinases (MMPs), and tissue inhibitor MMPs (TIMPs) were upregulated. Expression of the antifibrotic miRNA29c-3p was significantly reduced. Apocynin supplementation ameliorated most of the age-related observed changes, sometimes to values similar to those observed in young females. These findings indicate that there is an age-related increase in OS that plays an important role in enhancing inflammation and collagen deposition, contributing to a decline in female fertility. Apocynin supplementation suggests that the imbalance can be ameliorated and thus delay ovarian ageing harmful effects.

Modulation of Intracellular ROS and Senescence-Associated Phenotypes of Xenopus Oocytes and Eggs by Selective Antioxidants

“…The drug was reported to display antiinflammatory properties in acute lung inflammation [49,50] and in bronchial asthma [51] where oxidative stress was proven to be involved in disease pathogenesis; apocynin reduced ROS concentrations in exhaled breath condensate in asthmatics. More recently, it was demonstrated that dietary supplementation of apocynin ameliorates an age-related increase in ROS and delays mouse ovarian aging [52]. Now, our current study presents for the first time an evidence for beneficial effects of apocynin on isolated in vitro cultured oocytes and eggs.…”

Advanced Oxidation Protein Products Induce G1/G0‐Phase Arrest in Ovarian Granulosa Cells via the ROS‐JNK/p38 MAPK‐p21 Pathway in Premature Ovarian Insufficiency

“…The slides were examined and photographed using a Leica CS2 slide scanner system (Leica, Wetzlar, Germany). A follicle containing an oocyte with a distinct nucleus was counted and classified as a primordial, primary, secondary, antral, or atretic follicle according to previously described criteria [ 21 ]. The number of follicles was calculated from the total counts of three representative ovarian midsections of each rat.…”

The role of oxidative stress in ovarian aging: a review

“…OS and inflammation produce synergistic disruptive effects on ovarian tissue. A previous study showed that the levels of the products of OS damage (carbonylated and nitrated proteins) and inflammatory markers (TNF-α, IL-1β) were significantly higher in the ovaries of aged mice than in younger mice [ 39 ]. Ovarian RNA transcriptome analysis further revealed that OS-related proteins (Nrf2, SOD2, CAT, GSH-px1) and genes encoding NLRP3 inflammatory vesicles could be used as key biomarkers to differentiate between young and aging mice [ 40 ].…”