High-fat feeding reprograms maternal energy metabolism and induces long-term postpartum obesity in mice
INTERNATIONAL JOURNAL OF OBESITY
Authors: Qiao, Liping; Chu, Kayee; Wattez, Jean-Sebastien; Lee, Samuel; Gao, Hongfei; Feng, Gen-Sheng; Hay, William W., Jr.; Shao, Jianhua
Abstract
Background Excessive gestational weight gain (EGWG) closely associates with postpartum obesity. However, the causal role of EGWG in postpartum obesity has not been experimentally verified. The objective of this study was to determine whether and how EGWG causes long-term postpartum obesity. Methods C57BL/6 mice were fed with high-fat diet during gestation (HFFDG) or control chow, then their body composition and energy metabolism were monitored after delivery. Results We found that HFFDG significantly increased gestational weight gain. After delivery, adiposity of HFFDG-treated mice (Preg-HF) quickly recovered to the levels of controls. However, 3 months after parturition, Preg-HF mice started to gain significantly more body fat even with regular chow. The increase of body fat of Preg-HF mice was progressive with aging and by 9 months after delivery had increased 2-fold above the levels of controls. The expansion of white adipose tissue (WAT) of Preg-HF mice was manifested by hyperplasia in visceral fat and hypertrophy in subcutaneous fat. Preg-HF mice developed low energy expenditure and UCP1 expression in interscapular brown adipose tissue (iBAT) in later life. Although blood estrogen concentrations were similar between Preg-HF and control mice, a significant decrease in estrogen receptor a (ER alpha) expression and hypermethylation of the ER alpha promoter was detected in the fat of Preg-HF mice 9 months after delivery. Interestingly, hypermethylation of ER alpha promoter and low ER alpha expression were only detected in adipocyte progenitor cells in both iBAT and WAT of Preg-HF mice at the end of gestation. Conclusions These results demonstrate that HFFDG causes long-term postpartum obesity independent of early postpartum fat retention. This study also suggests that HFFDG adversely programs long-term postpartum energy metabolism by epigenetically reducing estrogen signaling in both BAT and WAT.
2-Aminoadipic acid protects against obesity and diabetes
JOURNAL OF ENDOCRINOLOGY
Authors: Xu, Wang-Yang; Shen, Yan; Zhu, Houbao; Gao, Junhui; Zhang, Chen; Tang, Lingyun; Lu, Shun-Yuan; Shen, Chun-Ling; Zhang, Hong-Xin; Li, Ziwei; Meng, Peng; Wan, Ying-Han; Fei, Jian; Wang, Zhu-Gang
Abstract
Obesity and type 2 diabetes (T2D) are both complicated endocrine disorders resulting from an interaction between multiple predisposing genes and environmental triggers, while diet and exercise have key influence on metabolic disorders. Previous reports demonstrated that 2-aminoadipic acid (2-AAA), an intermediate metabolite of lysine metabolism, could modulate insulin secretion and predict T2D, suggesting the role of 2-AAA in glycolipid metabolism. Here, we showed that treatment of diet-induced obesity (DIO) mice with 2-AAA significantly reduced body weight, decreased fat accumulation and lowered fasting glucose. Furthermore, Dhtkd1(-/-) mice, in which the substrate of DHTKD1 2-AAA increased to a significant high level, were resistant to DIO and obesity-related insulin resistance. Further study showed that 2-AAA induced higher energy expenditure due to increased adipocyte thermogenesis via upregulating PGC1 alpha and UCP1 mediated by beta 3AR activation, and stimulated lipolysis depending on enhanced expression of hormone-sensitive lipase (HSL) through activating beta 3AR signaling. Moreover, 2-AAA could alleviate the diabetic symptoms of db/db mice. Our data showed that 2-AAA played an important role in regulating glycolipid metabolism independent of diet and exercise, implying that improving the level of 2-MA in vivo could be developed as a strategy in the treatment of obesity or diabetes.