HIGD1A links SIRT1 activity to adipose browning by inhibiting the ROS/DNA damage pathway
Bai-Yu Li,
Wan-Qiu Peng,
Yang Liu,
Liang Guo,
Qi-Qun Tang
Affiliations
Bai-Yu Li
Key Laboratory of Metabolism and Molecular Medicine of the Ministry of Education, Department of Biochemistry and Molecular Biology of School of Basic Medical Sciences and Department of Endocrinology and Metabolism of Zhongshan Hospital, Fudan University, Shanghai 200032, China
Wan-Qiu Peng
Key Laboratory of Metabolism and Molecular Medicine of the Ministry of Education, Department of Biochemistry and Molecular Biology of School of Basic Medical Sciences and Department of Endocrinology and Metabolism of Zhongshan Hospital, Fudan University, Shanghai 200032, China
Yang Liu
Key Laboratory of Metabolism and Molecular Medicine of the Ministry of Education, Department of Biochemistry and Molecular Biology of School of Basic Medical Sciences and Department of Endocrinology and Metabolism of Zhongshan Hospital, Fudan University, Shanghai 200032, China
Liang Guo
School of Exercise and Health and Shanghai Frontiers Science Research Base of Exercise and Metabolic Health, Shanghai University of Sport, Shanghai 200438, China; Corresponding author
Qi-Qun Tang
Key Laboratory of Metabolism and Molecular Medicine of the Ministry of Education, Department of Biochemistry and Molecular Biology of School of Basic Medical Sciences and Department of Endocrinology and Metabolism of Zhongshan Hospital, Fudan University, Shanghai 200032, China; Corresponding author
Summary: Energy-dissipating adipocytes have the potential to improve metabolic health. Here, we identify hypoxia-induced gene domain protein-1a (HIGD1A), a mitochondrial inner membrane protein, as a positive regulator of adipose browning. HIGD1A is induced in thermogenic fats by cold exposure. Peroxisome proliferator-activated receptor gamma (PPARγ) transactivates HIGD1A expression synergistically with peroxisome proliferators-activated receptor γ coactivator α (PGC1α). HIGD1A knockdown inhibits adipocyte browning, whereas HIGD1A upregulation promotes the browning process. Mechanistically, HIGD1A deficiency impairs mitochondrial respiration to increase reactive oxygen species (ROS) level. This increases NAD+ consumption for DNA damage repair and curtails the NAD+/NADH ratio, which inhibits sirtuin1 (SIRT1) activity, thereby compromising adipocyte browning. Conversely, overexpression of HIGD1A blunts the above process to promote adaptive thermogenesis. Furthermore, mice with HIGD1A knockdown in inguinal and brown fat have impaired thermogenesis and are prone to diet-induced obesity (DIO). Overexpression of HIGD1A favors adipose tissue browning, ultimately preventing DIO and metabolic disorders. Thus, the mitochondrial protein HIGD1A links SIRT1 activity to adipocyte browning by inhibiting ROS levels.