Rho-kinase inhibition ameliorates metabolic disorders through activation of AMPK pathway in mice

• Published in: PloS one 2014-11, Vol.9 (11), p.e110446-e110446
• Main Authors: Noda, Kazuki, Nakajima, Sota, Godo, Shigeo, Saito, Hiroki, Ikeda, Shohei, Shimizu, Toru, Enkhjargal, Budbazar, Fukumoto, Yoshihiro, Tsukita, Sohei, Yamada, Tetsuya, Katagiri, Hideki, Shimokawa, Hiroaki
• Format: Article
• Language: English
• Subjects: Activation; AMP; AMP-Activated Protein Kinases - deficiency; AMP-Activated Protein Kinases - genetics; AMP-Activated Protein Kinases - metabolism; Animal tissues; Animals; Apoptosis; Binding proteins; Body weight; Cardiovascular diseases; Cell adhesion & migration; Cell Line; Diabetes; Diet, High-Fat; Disease Models, Animal; Disorders; Drinking water; Energy metabolism; Energy Metabolism - drug effects; Enzyme Activation - drug effects; Enzyme inhibitors; Exercise; Experiments; Fatty acids; Female; Gene Expression; Glucose; Glucose metabolism; Glucose tolerance; GTP-binding protein; Health aspects; Health risks; High fat diet; Hypercholesterolemia; Hypertension; Inhibition; Inhibitors; Insulin; Intolerance; Kinases; Laboratory animals; Lipid metabolism; Lipids; Liver; LKB1 protein; Male; Medicine; Medicine and Health Sciences; Metabolic Diseases - genetics; Metabolic Diseases - metabolism; Metabolic disorders; Metabolic rate; Metabolic syndrome; Metabolism; Mice; Mice, Knockout; Mitochondria; Models, Biological; Muscle contraction; Muscle, Skeletal - drug effects; Muscle, Skeletal - metabolism; Muscles; Musculoskeletal system; Myocytes; Obesity; Oxidation; Pharmacology; Phenotype; Physical activity; Physical fitness; Protein binding; Protein Kinase Inhibitors - pharmacology; Protein-Serine-Threonine Kinases - metabolism; Proteins; Research and Analysis Methods; Rho-associated kinase; rho-Associated Kinases - antagonists & inhibitors; rho-Associated Kinases - genetics; RhoA protein; Risk analysis; Risk factors; RNA; Rodents; Signal Transduction - drug effects; Skeletal muscle; University graduates
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0110446

Metabolic disorders, caused by excessive calorie intake and low physical activity, are important cardiovascular risk factors. Rho-kinase, an effector protein of the small GTP-binding protein RhoA, is an important cardiovascular therapeutic target and its activity is increased in patients with metabolic syndrome. We aimed to examine whether Rho-kinase inhibition improves high-fat diet (HFD)-induced metabolic disorders, and if so, to elucidate the involvement of AMP-activated kinase (AMPK), a key molecule of metabolic conditions. Mice were fed a high-fat diet, which induced metabolic phenotypes, such as obesity, hypercholesterolemia and glucose intolerance. These phenotypes are suppressed by treatment with selective Rho-kinase inhibitor, associated with increased whole body O2 consumption and AMPK activation in the skeletal muscle and liver. Moreover, Rho-kinase inhibition increased mRNA expression of the molecules linked to fatty acid oxidation, mitochondrial energy production and glucose metabolism, all of which are known as targets of AMPK in those tissues. In systemic overexpression of dominant-negative Rho-kinase mice, body weight, serum lipid levels and glucose metabolism were improved compared with littermate control mice. Furthermore, in AMPKα2-deficient mice, the beneficial effects of fasudil, a Rho-kinase inhibitor, on body weight, hypercholesterolemia, mRNA expression of the AMPK targets and increase of whole body O2 consumption were absent, whereas glucose metabolism was restored by fasudil to the level in wild-type mice. In cultured mouse myocytes, pharmacological and genetic inhibition of Rho-kinase increased AMPK activity through liver kinase b1 (LKB1), with up-regulation of its targets, which effects were abolished by an AMPK inhibitor, compound C. These results indicate that Rho-kinase inhibition ameliorates metabolic disorders through activation of the LKB1/AMPK pathway, suggesting that Rho-kinase is also a novel therapeutic target of metabolic disorders.