ABSTRACT
Adiponectin (Ad) is an abundant protein hormone that regulates numerous metabolic processes. Th e 30 kDa protein mainly originates from adipose tissue, with both full-length and globular domain forms existing in the bloodstream. A collagenous domain within adiponectin leads to its spontaneous self-assembly into various oligomeric isoforms, including trimers, hexamers, and high molecular weight multimers. Two membrane-spanning receptors for adiponectin have been identifi ed, with diff ering concentration distribution in various body tissues. Th e major intracellular pathway activated by adiponectin includes phosphorylation of AMP-activated protein kinase, responsible for many of adiponectin’s downstream actions, including increased glucose utilization, fatty acid oxidation, increased muscle glucose uptake, and decreased liver gluconeogenesis.
