Melanopsin function in temperature perception in 3T3-L1 cells: a link between temperature control and regulation of the physiology of adipose tissue

• Grant number: 18/14286-7
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Effective date (Start): March 01, 2019
• Effective date (End): December 31, 2020
• Field of knowledge: Biological Sciences - Physiology - Physiology of Organs and Systems
• Principal Investigator: Maria Nathália de Carvalho Magalhães Moraes Figueira Borges
• Grantee: Giovanna Zanetti
• Host Institution: Instituto de Biociências (IB). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

In mammals, there is a network of central and peripheral circadian clocks, regulating behavioral and biochemical processes in the organism. Light information travels through the retina and activates a series of opsins, among which is the photopigment melanopsin (OPN4) present in intrinsically photosensitive cells (ipRGCs) which constitute about 2% of the ganglion cell layer. Melanopsin participates in the adjustment of the central biological clock, the suprachiasmatic nucleus, transforming the photic energy into an electrical signal and, thus, sends the information of the ambient light through the retinohypothalamic tract to these nuclei. In addition to the classical expression in the retina, opsins were identified in peripheral "blind" tissues, such as brown (BAT) and white (WAT) adipose tissues), liver, lung, adrenal and heart. The functional role of melanopsin has been established in the mechanism of photo-relaxation of vessels in response to blue light stimulation. In addition, adipocytes stimulated by blue light present a reduction in the accumulation of lipids and increased secretion of leptin. As surprising as the data presented above was the finding that melanopsin can also be activated by thermal energy. These data together break the paradigm that melanopsin participates only in retinal photic responses and thus include it in a family of bifunctional molecules that have the potential to perceive temperature and light. In this work, we will investigate the activation of the biological clock in murine pre-adipocytes in response to thermal stimuli and possible participation of melanopsin in this process.