Abstract | AIM: MATERIALS AND METHODS: Fourteen- to eighteen-week-old db/db diabetic and db/+ non-diabetic mice were intraperitoneally treated with desacyl ghrelin at a dosage of 100 μg/kg for ten consecutive days. Ventricular fractional shortening was examined as an indicator of cardiac function by transthoracic echocardiography. RESULTS: The presence of diabetic cardiomyopathy was evident by the reduction in fractional shortening shown in our examined db/db mice. Intriguingly, this reduction in fractional shortening was not observed in the hearts of db/db mice treated with desacyl ghrelin. Cardiac fibrosis (indicated by excessive collagen deposition, decreased by Adiponectin and Mmp13 expression, and up-regulated by Mmp8 expression) and impairment of autophagic signalling (indicated by decreases in Foxo3 and LC3 II-to-LC3 I ratio) were shown in the hearts of diabetic mice. All these cellular and molecular alterations were alleviated by desacyl ghrelin treatment. The key cardiac pro-survival cellular signals including AMPK, Akt, ERK1/2, and GSK3α/β were impaired in the diabetic hearts, but the administration of desacyl ghrelin attenuated these signalling impairments. CONCLUSIONS: These results collectively demonstrate that desacyl ghrelin protects the heart against cardiac dysfunction in type 2 diabetic mice by inhibiting excessive collagen deposition and enhancing cardiac autophagic signalling via the pro-survival cellular AMPK/ERK1/2 signalling pathways.
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Authors | Xiao M Pei, Benjamin Y Yung, Shea P Yip, Lawrence W Chan, Cesar S Wong, Michael Ying, Parco M Siu |
Journal | Acta diabetologica
(Acta Diabetol)
Vol. 52
Issue 2
Pg. 293-306
(Apr 2015)
ISSN: 1432-5233 [Electronic] Germany |
PMID | 25192951
(Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
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Chemical References |
- Adiponectin
- Ghrelin
- ghrelin, des-n-octanoyl
- Matrix Metalloproteinase 8
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Topics |
- Adiponectin
(genetics, metabolism)
- Animals
- Diabetes Mellitus, Type 2
(complications)
- Diabetic Cardiomyopathies
(etiology, genetics, physiopathology, prevention & control)
- Disease Models, Animal
- Ghrelin
(administration & dosage)
- Heart
(physiopathology)
- Humans
- Male
- Matrix Metalloproteinase 8
(genetics, metabolism)
- Mice
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