bims-mifefi 2024-05-05 papers

Issue of 2024‒05‒05
four papers selected by
Kayla Vandiver, East Carolina University

Physiol Rep. 2024 May;12(9): e16028

Effects of maternal exercise on infant mesenchymal stem cell mitochondrial function, insulin action, and body composition in infancy.

Filip Jevtovic, Donghai Zheng, Alex Claiborne, Ericka M Biagioni, Breanna L Wisseman, Polina M Krassovskaia, David N Collier, Christy Isler, James E DeVente, P Darrell Neufer, Joseph A Houmard, Linda E May.

Maternal exercise (ME) has been established as a useful non-pharmacological intervention to improve infant metabolic health; however, mechanistic insight behind these adaptations remains mostly confined to animal models. Infant mesenchymal stem cells (MSCs) give rise to infant tissues (e.g., skeletal muscle), and remain involved in mature tissue maintenance. Importantly, these cells maintain metabolic characteristics of an offspring donor and provide a model for the investigation of mechanisms behind infant metabolic health improvements. We used undifferentiated MSC to investigate if ME affects infant MSC mitochondrial function and insulin action, and if these adaptations are associated with lower infant adiposity. We found that infants from exercising mothers have improvements in MSC insulin signaling related to higher MSC respiration and fat oxidation, and expression and activation of energy-sensing and redox-sensitive proteins. Further, we found that infants exposed to exercise in utero were leaner at 1 month of age, with a significant inverse correlation between infant MSC respiration and infant adiposity at 6 months of age. These data suggest that infants from exercising mothers are relatively leaner, and this is associated with higher infant MSC mitochondrial respiration, fat use, and insulin action.

Keywords: childhood obesity; insulin action; maternal exercise; mitochondria; pregnancy

DOI: https://doi.org/10.14814/phy2.16028

J Steroid Biochem Mol Biol. 2024 Apr 29. pii: S0960-0760(24)00087-6. [Epub ahead of print] 106539

Metabolism of Endogenous and Exogenous Estrogens in Women.

Frank Z Stanczyk.

Estrogens regulate important processes in reproductive, skeletal, cardiovascular, and central nervous systems that impact women's overall health. Understanding endogenous and exogenously administered estrogen metabolism is vital to determining therapeutic estrogen levels. The present review provides an overview of estrogen metabolites formed in non-pregnant and pregnant women, and those resulting from exogenous estrogen administration. There are four principal endogenous estrogens: estrone (E1), estradiol (E2), estriol (E3), and estetrol (E4). E4, which is produced only in pregnancy, has emerged recently as an estrogen with significant therapeutic potential. E1, E2, and E3 undergo extensive metabolism primarily through phase I (hydroxylation, oxidation, reduction) and phase II (primarily conjugation) reactions, whereas E4 undergoes only phase II reactions. Exogenous estrogens commonly used for menopausal treatment and/or contraception, including micronized E2, conjugated equine estrogens, and ethinyl estradiol, also undergo phase I and phase II reactions, but differ widely in the types of metabolites formed. The mechanisms by which estrogen metabolites are formed and their excretion in urine, bile, and feces, are still poorly understood. We highlight areas that require further research to foster a better understanding of how estrogen metabolism impacts dosing of estrogens for therapeutic use, as well as the physiological regulation of endogenous estrogens.

Keywords: conjugated equine estrogens; estetrol; estradiol; estrogens; metabolism

DOI: https://doi.org/10.1016/j.jsbmb.2024.106539

Obes Rev. 2024 May 02. e13760

The effects of dietary macronutrient composition on resting energy expenditure following active weight loss: A systematic review and meta-analysis.

Dang Khanh Ngan Ho, Yu Chi Liao, Noor Rohmah Mayasari, Mu-Ming Chien, Mei Chung, Chyi-Huey Bai, Ya-Li Huang, Yang-Ching Chen, Sung-Hui Tseng, Chun-Chao Chang, Wan-Chun Chiu, Patchara Sangopas, Hsiang-Tung Tseng, Jing Wen Kao, Yi Jing Ngu, Jung-Su Chang.

A systematic review and meta-analysis was conducted to evaluate the relative effectiveness of different dietary macronutrient patterns on changes in resting energy expenditure (REE) in relation to weight loss, categorized as minimal (<5%) and moderate to high (>5%). Changes in REE were assessed using a DerSimonian and Laird random-effects meta-analysis. A diet lower in carbohydrates (CHO) or higher in fat and protein was associated with smaller reductions in REE, with these trends being more pronounced among participants who experienced moderate to high weight loss. Adjusted meta-regression analysis indicated that, within the participants who experienced moderate to high weight loss, each 1% increase in CHO intake was associated with a reduction of 2.30 kcal/day in REE (95% CI: -4.11 to -0.47, p = 0.013). In contrast, a 1% increase in protein and fat intake was correlated with an increase in REE by 3.00 (95% confidence interval [CI] [1.02, 5.07], p = 0.003) and 0.5 (95% CI [-2.43, 3.41], p = 0.740) kcal/day, respectively. No significant associations were found among participants who experienced minimal weight loss. These findings indicate that, under a caloric deficit, the impact of dietary macronutrient composition on REE may vary depending on the degree of weight loss and individual metabolic responses.

Keywords: calorie restriction; low‐carbohydrate and low‐fat diet; resting energy expenditure

DOI: https://doi.org/10.1111/obr.13760