The muscle, for example, is known as a motor organ, but compelling evidence has implied that it is also an endocrine organ, secreting hundred proteins (known as myokines) during exercise that enter circulatory system and function as endocrine modulators mediating the adaption of organs and tissues to exercise ( 4). It has long been suspected that physiological functions are mediated through the inter-organ communications ( 1– 3), and such communications mainly occur through secreted molecules. To best our understanding of the regulatory mechanism, this review discusses the recent evidence involving the potential molecular pathways of the inter-organ communications, and the interactions between signalings and irisin in regulating the impact of exercise on organ functions are also discussed. It is secreted under the regulation of exercise and mediates the intercommunications between exercise and organs.

A recently identified myokine–irisin, primarily found in muscle and adipose and subsequently extending to bone, heart, liver and brain, provides a new molecular evidence for the inter-organ communications. However, the underlying mechanism how exercise regulates the inter-organ communications remains incompletely understood yet. That exercise can improve the physiological function of organs or tissues is believed by secreting myokines from muscle to target remote organs.

The physiological functions of organs are intercommunicated occurring through secreted molecules. College of Physical Education, Yangzhou University, Yangzhou, China.

Crossroads by J.J. Bonds