RT Journal Article
T1 Leptin induces cardiac fibrosis through galectin-3, mTOR and oxidative stress: potential role in obesity
A1 Martínez Martínez, Ernesto
A1 Jurado López, Raquel
A1 Valero Muñoz, María
A1 Bartolomé Pascual, María Visitación
A1 Ballesteros Rodrigálvarez, Sandra María
A1 Luaces Méndez, María
A1 Briones, Ana María
A1 López Andrés, Natalia
A1 Miana, María
A1 Cachofeiro Ramos, María Victoria
AB Objective: Leptin acts as a cardiac profibrotic factor. However, the mechanisms underlying this effect are unclear. Therefore, we sought to elucidate the mediators involved in this process and the potential role of leptin in cardiac fibrosis associated with obesity.Methods: Male Wistar rats were fed either a high-fat diet (HFD; 33.5% fat), or a standard diet (3.5% fat) for 6 weeks.Results: HFD animals show cardiac hypertrophy, fibrosis and an increase in O2- production as evaluated by dihydroethidium. Echocardiographic parameters of cardiac structure and systolic function were similar in both groups. Cardiac levels of leptin, collagen I, galectin-3 and transforming growth factor β (TGF-β) were higher in HFD than in controls. In cardiac myofibroblasts, leptin (10-100 ng/ml) increased O2-, collagen I, galectin-3, TGF-β and connective tissue growth factor production (CTGF). These effects were prevented by the presence of either melatonin (10 mmol/l) or the inhibitor of mTOR, rapamycin (10 mmol/l). Blockage of galectin-3 activity by N-acetyllactosamine (LacNac 10 mmol/l) reduced both collagen I and O2(*-) production induced by leptin. The p70S6 kinase activation/phosphorylation, the downstream mediator of mTOR, induced by leptin was not modified by melatonin. Leptin reduced the metalloproteinase (MMP) 2 activity and the presence of melatonin, rapamycin or LacNac were unable to prevent it.Conclusion: The data suggest that leptin locally produced in the heart could participate in the fibrosis observed in HFD by affecting collagen turnover. Collagen synthesis induced by leptin seems to be mediated by the production of galectin-3, TGF-β and CTGF through oxidative stress increased by activation of mTOR pathway.
PB Lippincott, Williams & Wilkins
SN 0263-6352
YR 2014
FD 2014-05-01
LK https://hdl.handle.net/20.500.14352/115765
UL https://hdl.handle.net/20.500.14352/115765
LA eng
NO Martínez-Martínez E, Jurado-López R, Valero-Muñoz M, Bartolomé MV, Ballesteros S, Luaces M, Briones AM, López-Andrés N, Miana M, Cachofeiro V. Leptin induces cardiac fibrosis through galectin-3, mTOR and oxidative stress: potential role in obesity. J Hypertens. 2014 May;32(5):1104-14.
NO Ministerio de Sanidad (España)
DS Docta Complutense
RD 9 abr 2025