Kelsey Timme, M. Estefanía González-Alvarez, Aileen F. Keating
{"title":"Pre-pubertal obesity compromises ovarian oxidative stress, DNA repair and chemical biotransformation","authors":"Kelsey Timme, M. Estefanía González-Alvarez, Aileen F. Keating","doi":"10.1016/j.taap.2024.116981","DOIUrl":null,"url":null,"abstract":"<div><p>Obesity in adult females impairs fertility by altering oxidative stress, DNA repair and chemical biotransformation. Whether prepubertal obesity results in similar ovarian impacts is under-explored. The objective of this study was to induce obesity in prepubertal female mice and assess puberty onset, follicle number, and abundance of oxidative stress, DNA repair and chemical biotransformation proteins basally and in response to 7,12-dimethylbenz(<em>a</em>)anthracene (DMBA) exposure. DMBA is a polycyclic aromatic hydrocarbon that has been shown to be ovotoxic. Lactating dams (C57BL6J) were fed either a normal rodent containing 3.5% kCal from fat (lean), or a high fat diet comprised of 60% kCal from fat, and 9% kCal from sucrose. The offspring were weaned onto the diet of their dam and exposed at postnatal day 35 to either corn oil or DMBA (1 mg/kg) for 7 d via intraperitoneal injection. Mice on the HFD had reduced (<em>P</em> < 0.05) age at puberty onset as measured by vaginal opening but DMBA did not impact puberty onset. Heart, spleen, kidney, uterus and ovary weight were increased (<em>P</em> < 0.05) by obesity and liver weight was increased (<em>P</em> < 0.05) by DMBA exposure in obese mice. Follicle number was largely unaffected by obesity or DMBA exposure, with the exception of primary follicle number, which were higher (<em>P</em> < 0.05) in lean DMBA exposed and obese control relative to lean control mice. There were also greater numbers (<em>P</em> < 0.05) of corpora lutea in obese relative to lean mice. In lean mice, DMBA exposure reduced (<em>P</em> < 0.05) the level of CYP2E1, EPHX1, GSTP1, BRCA1, and CAT but this DMBA-induced reduction was absent in obese mice. Basally, obesity reduced (<em>P</em> < 0.05) the abundance of CYP2E1, EPHX1, GSTP1, BRCA1, SOD1 and CAT. There was greater (<em>P</em> < 0.05) fibrotic staining in obese DMBA-exposed ovaries and PPP2CA was decreased (<em>P</em> < 0.05) in growing follicles by both obesity and DMBA exposure. Thus, prepubertal obesity alters the capacity of the ovary to respond to DNA damage, ovotoxicant exposure and oxidative stress.</p></div>","PeriodicalId":23174,"journal":{"name":"Toxicology and applied pharmacology","volume":"489 ","pages":"Article 116981"},"PeriodicalIF":3.3000,"publicationDate":"2024-06-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Toxicology and applied pharmacology","FirstCategoryId":"3","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0041008X24001790","RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"PHARMACOLOGY & PHARMACY","Score":null,"Total":0}
引用次数: 0
Abstract
Obesity in adult females impairs fertility by altering oxidative stress, DNA repair and chemical biotransformation. Whether prepubertal obesity results in similar ovarian impacts is under-explored. The objective of this study was to induce obesity in prepubertal female mice and assess puberty onset, follicle number, and abundance of oxidative stress, DNA repair and chemical biotransformation proteins basally and in response to 7,12-dimethylbenz(a)anthracene (DMBA) exposure. DMBA is a polycyclic aromatic hydrocarbon that has been shown to be ovotoxic. Lactating dams (C57BL6J) were fed either a normal rodent containing 3.5% kCal from fat (lean), or a high fat diet comprised of 60% kCal from fat, and 9% kCal from sucrose. The offspring were weaned onto the diet of their dam and exposed at postnatal day 35 to either corn oil or DMBA (1 mg/kg) for 7 d via intraperitoneal injection. Mice on the HFD had reduced (P < 0.05) age at puberty onset as measured by vaginal opening but DMBA did not impact puberty onset. Heart, spleen, kidney, uterus and ovary weight were increased (P < 0.05) by obesity and liver weight was increased (P < 0.05) by DMBA exposure in obese mice. Follicle number was largely unaffected by obesity or DMBA exposure, with the exception of primary follicle number, which were higher (P < 0.05) in lean DMBA exposed and obese control relative to lean control mice. There were also greater numbers (P < 0.05) of corpora lutea in obese relative to lean mice. In lean mice, DMBA exposure reduced (P < 0.05) the level of CYP2E1, EPHX1, GSTP1, BRCA1, and CAT but this DMBA-induced reduction was absent in obese mice. Basally, obesity reduced (P < 0.05) the abundance of CYP2E1, EPHX1, GSTP1, BRCA1, SOD1 and CAT. There was greater (P < 0.05) fibrotic staining in obese DMBA-exposed ovaries and PPP2CA was decreased (P < 0.05) in growing follicles by both obesity and DMBA exposure. Thus, prepubertal obesity alters the capacity of the ovary to respond to DNA damage, ovotoxicant exposure and oxidative stress.
期刊介绍:
Toxicology and Applied Pharmacology publishes original scientific research of relevance to animals or humans pertaining to the action of chemicals, drugs, or chemically-defined natural products.
Regular articles address mechanistic approaches to physiological, pharmacologic, biochemical, cellular, or molecular understanding of toxicologic/pathologic lesions and to methods used to describe these responses. Safety Science articles address outstanding state-of-the-art preclinical and human translational characterization of drug and chemical safety employing cutting-edge science. Highly significant Regulatory Safety Science articles will also be considered in this category. Papers concerned with alternatives to the use of experimental animals are encouraged.
Short articles report on high impact studies of broad interest to readers of TAAP that would benefit from rapid publication. These articles should contain no more than a combined total of four figures and tables. Authors should include in their cover letter the justification for consideration of their manuscript as a short article.