| First Author | Jaquenod De Giusti C | Year | 2019 |
| Journal | J Mol Cell Cardiol | Volume | 136 |
| Pages | 53-63 | PubMed ID | 31518570 |
| Mgi Jnum | J:281532 | Mgi Id | MGI:6376907 |
| Doi | 10.1016/j.yjmcc.2019.09.005 | Citation | Jaquenod De Giusti C, et al. (2019) Carbonic anhydrase II/sodium-proton exchanger 1 metabolon complex in cardiomyopathy of ob(-/-) type 2 diabetic mice. J Mol Cell Cardiol 136:53-63 |
| abstractText | Heart failure is the leading cause of death among diabetic people. Cellular and molecular entities leading to diabetic cardiomyopathy are, however, poorly understood. Coupling of cardiac carbonic anhydrase II (CAII) and Na(+)/H(+) exchanger 1 (NHE1) to form a transport metabolon was analyzed in obese type 2 diabetic mice (ob(-/-)) and control heterozygous littermates (ob(+/-)). Echocardiography showed elevated systolic interventricular septum thickness and systolic posterior wall thickness in ob(-/-) mice at 9 and 16weeks. ob(-/-) mice showed increased left ventricular (LV) weight/tibia length ratio and increased cardiomyocyte cross sectional area as compared to controls, indicating cardiac hypertrophy. Immunoblot analysis showed increased CAII expression in LV samples of ob(-/-)vs. ob(+/-) mice, and augmented Ser(703) phosphorylation on NHE1 in ob(-/-) hearts. Reciprocal co-immunoprecipitation analysis showed strong association of CAII and NHE1 in LV samples of ob(-/-) mice. NHE1-dependent rate of intracellular pH (pHi) normalization after transient acid loading of isolated cardiomyocytes was higher in ob(-/-) mice vs. ob(+/-). NHE transport activity was also augmented in cultured H9C2 rat cardiomyoblasts treated with high glucose/high palmitate, and it was normalized after CA inhibition. We conclude that the NHE1/CAII metabolon complex is exacerbated in diabetic cardiomyopathy of ob(-/-) mice, which may lead to perturbation of pHi and [Na(+)] and [Ca(2+)] handling in these diseased hearts. |
