Search

Sarcopenia is the gradual decreases of skeletal muscle mass and functions during aging. In general, muscle mass index as a predictor of sarcopenia should be well reflected by those of functions. Ho...

WNK (with-no-lysine [K]) kinases (WNK1-4) are serine/threonine protein kinases with an atypical placement of the catalytic lysine and tissue-specific expression. WNK1, ubiquitously expressed including skeletal muscle, is known as a downstream effector of insulin signaling and WNKs have been implicated in protein trafficking highly correlated with insulin resistance or diabetes. However, expression pattern and functional role of WNKs in skeletal muscle and linkage between WNKs and insulin signaling effectors such as PKB/Akt and glucose transports in skeletal muscle with type II diabetes are ill-defined. In the present study, WNK1 and WNK2, not WNK4 are expressed in C2C12. The expression levels of WNK1 and WNK2 significantly decreased in db/db mice, a type II diabetic model, compared to that of wild type mice. Phosphorylated Akt in skeletal muscle decreased in db/db mice supporting insulin resistance in skeletal muscle. Insulin stimulates Akt followed by WNK1 phosphorylation. Insulin stimulation of WNK1 is ...