Adipocyte dysfunction is the driver of obesity and correlates with insulin resistance and the
onset of type 2 diabetes. Protein kinase N1 (PKN1) is a serine/threonine kinase that has been shown
to contribute to Glut4 translocation to the membrane and glucose transport. Here, we evaluated the
role of PKN1 in glucose metabolism under insulin-resistant conditions in primary visceral adipose
tissue (VAT) from 31 patients with obesity and in murine 3T3-L1 adipocytes. In addition, in vitro
studies in human VAT samples and mouse adipocytes were conducted to investigate the role of
PKN1 in the adipogenic maturation process and glucose homeostasis control. We show that insulinresistant adipocytes present a decrease in PKN1 activation levels compared to nondiabetic control
counterparts. We further show that PKN1 controls the adipogenesis process and glucose metabolism.
PKN1-silenced adipocytes present a decrease in both differentiation process and glucose uptake,
with a concomitant decrease in the expression levels of adipogenic markers, such as PPARγ, FABP4,
adiponectin and CEBPα. Altogether, these results point to PKN1 as a regulator of key signaling
pathways involved in adipocyte differentiation and as an emerging player of adipocyte insulin
responsiveness. These findings may provide new therapeutic approaches for the management of
insulin resistance in type 2 diabetes.
