The MicroRNA miR-696 is regulated by SNARK and reduces mitochondrial activity in mouse skeletal muscle through Pgc1 alpha inhibition

Author(s):Show less -

Queiroz, Andre L. ^{[1, 2, 3]} ; Lessard, Sarah J. ^{[2, 3]} ; Ouchida, Amanda T. ^[1] ; Araujo, Hygor N. ^[4] ; Goncalves, Dawit A. ^[1] ; Guimaraes, Dimitrius Santiago P. Simoes Frees ^[4] ; Teodoro, Bruno G. ^{[1, 5]} ; So, Kawai ^{[2, 3]} ; Esprea, Enilza M. ^[6] ; Hirshman, Michael F. ^{[2, 3]} ; Alberici, Luciane C. ^[5] ; Kettelhut, Isis do Carmo ^[1] ; Goodyear, Laurie J. ^{[2, 3]} ; Silveira, Leonardo R. ^[4]

Affiliation

^[1] Univ Sao Paulo, Ribeirao Preto Med Sch, Dept Biochem & Immunol, Ribeirao Preto - Brazil

^[2] Harvard Med Sch, Brigham & Womens Hosp, Dept Med, Boston, MA 02115 - USA

^[3] Harvard Med Sch, Brigham & Womens Hosp, Joslin Diabet Ctr, Res Div, Boston, MA 02115 - USA

^[4] Univ Estadual Campinas, Obes & Comorbid Res Ctr, OCRC, IB, Campinas - Brazil

^[5] Univ Sao Paulo, Fac Pharmaceut Sci, Dept Phys & Chem, Ribeirao Preto - Brazil

^[6] Univ Sao Paulo, Ribeirao Preto Med Sch, Dept Cell Biol, Ribeirao Preto - Brazil

• Document type: Journal article
• Source: MOLECULAR METABOLISM; v. 51, SEP 2021.
• Web of Science Citations: 0

Abstract

Objective: MicroRNAs (miRNA) are known to regulate the expression of genes involved in several physiological processes including metabolism, mitochondrial biogenesis, proliferation, differentiation, and cell death. Methods: Using ``in silico{''} analyses, we identified 219 unique miRNAs that potentially bind to the 3'UTR region of a critical mitochondrial regulator, the peroxisome proliferator-activated receptor gamma coactivator (PGC) 1 alpha (Pgc1 alpha). Of the 219 candidate miRNAs, miR-696 had one of the highest interactions at the 3'UTR of Pgc1 alpha, suggesting that miR-696 may be involved in the regulation of Pgc1 alpha. Results: Consistent with this hypothesis, we found that miR-696 was highly expressed in the skeletal muscle of STZ-induced diabetic mice and chronic high-fat-fed mice. C2C12 muscle cells exposed to palmitic acid also exhibited a higher expression of miR-696. This increased expression corresponded with a reduced expression of oxidative metabolism genes and reduced mitochondrial respiration. Importantly, reducing miR-696 reversed decreases in mitochondrial activity in response to palmitic acid. Using C2C12 cells treated with the AMP-activated protein kinase (AMPK) activator AICAR and skeletal muscle from AMPK alpha 2 dominant-negative (DN) mice, we found that the signaling mechanism regulating miR-696 did not involve AMPK. In contrast, overexpression of SNF1-AMPK-related kinase (SNARK) in C2C12 cells increased miR-696 transcription while knockdown of SNARK significantly decreased miR-696. Moreover, muscle-specific transgenic mice overexpressing SNARK exhibited a lower expression of Pgc1 alpha, elevated levels of miR-696, and reduced amounts of spontaneous activity. Conclusions: Our findings demonstrate that metabolic stress increases miR-696 expression in skeletal muscle cells, which in turn inhibits Pgc1 alpha, reducing mitochondrial function. SNARK plays a role in this process as a metabolic stress signaling molecule inducing the expression of miR-696. (C) 2021 The Authors. Published by Elsevier GmbH. (AU)

• FAPESP's process: 13/22733-0 - Effect of miR-696 e miR-let7b on the mitochondrial function in insulin resistant muscle cells
• Grantee: Leonardo dos Reis Silveira
• Support Opportunities: Regular Research Grants