Interplay between obesity and aging on myocardial geometry and function: Role of leptin-STAT3-stress signaling

Title

Interplay between obesity and aging on myocardial geometry and function: Role of leptin-STAT3-stress signaling

Creator

Wei Jin
Fei Tu
Feng Dong
Qinqin Deng
Miyesaier Abudureyimu
Wei Yu
Guo-Jun Cai
Jian-Ming Pei
Zhaohui Pei
Jun Ren

Date

2022

Description

Background: Uncorrected obesity facilitates premature aging and cardiovascular anomalies. This study examined the interaction between obesity and aging on cardiac remodeling and contractile function.

Methods: Cardiac echocardiographic geometry, function, morphology, intracellular Ca2+ handling, oxidative stress (DHE fluorescence), STAT3 and stress signaling were evaluated in young (3-mo) and old (12- and 18-mo) lean and leptin deficient ob/ob obese mice. Cardiomyocytes from young and old lean and ob/ob mice were treated with leptin (1 nM) for 4 h in vitro prior to assessment of mechanical and biochemical properties. High fat diet (45% calorie from fat) and the leptin receptor mutant db/db obese mice at young and old age were evaluated for comparison.

Results: Our results displayed reduced survival in ob/ob mice. Obesity but less likely older age dampened echocardiographic, geometric, cardiomyocyte function and intracellular Ca2+ properties, elevated O2- and p47phox NADPH oxidase levels with a more pronounced geometric change at older age. Immunoblot analysis revealed elevated p47phox NADPH oxidase and dampened phosphorylation of STAT3, with a more pronounced response in old ob/ob mice, the effects were restored by leptin. Obesity and aging inhibited phosphorylation of Akt, eNOS, AMPK, and p38 while promoting phosphorylation of JNK and IκB. Leptin reconciled cardiomyocyte dysfunction, O2- yield, p47phox upregulation, STAT3 dephosphorylation and stress signaling in ob/ob mice although its action on stress signaling cascades were lost at old age. High fat diet-induced and db/db obesity displayed aging-associated cardiomyocyte anomalies reminiscent of ob/ob model albeit lost leptin response.

Conclusions: Our data suggest disparate age-associated obesity response in cardiac remodeling and contractile dysfunction due to phosphorylation of Akt, eNOS and stress signaling-related oxidative stress.

Source

Biochim Biophys Acta Gen Subj
. 2023 Feb;1867(2):130281. doi: 10.1016/j.bbagen.2022.130281. Epub 2022 Nov 18.

Language

English

Citation

Wei Jin et al., “Interplay between obesity and aging on myocardial geometry and function: Role of leptin-STAT3-stress signaling,” NEOMED Bibliography Database, accessed March 28, 2024, https://neomed.omeka.net/items/show/12203.