HIF-1a: CRAT: miR-144-3p axis dysregulation promotes osteoarthritis chondrocyte apoptosis and VLCFA accumulation
ONCOTARGET
Authors: Song, Jinsoo; Kang, Yeon-Ho; Yoon, Sik; Chun, Churl-Hong; Jin, Eun-Jung
Abstract
The functional role(s) of peroxisomes in osteoarthritis remains unclear. We demonstrated that peroxisomal dysfunction in osteoarthritis is responsible for very-long-chain fatty acid (VLCFA) accumulation. Through gene-profiling analyses, we identified CRAT as the gene responsible for this event. CRAT expression was suppressed in osteoarthritis chondrocytes, and its knockdown yielded pathological osteoarthritic characteristics, including VLCFA accumulation, apoptosis, autophagic inhibition, and mitochondrial dysfunction. Subsequent miRNA profiling revealed that peroxisomal dysfunction upregulates miR-144-3p, which overlapped with the osteoarthritis pathological characteristics observed upon CRAT knockdown. Moreover, knocking down HIF-1a in normal chondrocytes suppressed CRAT expression while stimulating miR-144-3p. Our data indicate that deregulation of a HIF-1a: CRAT: miR144- 3p axis impairs peroxisomal function during the pathogenesis of osteoarthritis.
Benzene Exposure Alters Expression of Enzymes Involved in Fatty Acid beta-Oxidation in Male C3H/He Mice
INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH
Authors: Sun, Rongli; Cao, Meng; Zhang, Juan; Yang, Wenwen; Wei, Haiyan; Meng, Xing; Yin, Lihong; Pu, Yuepu
Abstract
Benzene is a well-known hematotoxic carcinogen that can cause leukemia and a variety of blood disorders. Our previous study indicated that benzene disturbs levels of metabolites in the fatty acid beta-oxidation (FAO) pathway, which is crucial for the maintenance and function of hematopoietic and leukemic cells. The present research aims to investigate the effects of benzene on changes in the expression of key enzymes in the FAO pathway in male C3H/He mice. Results showed that benzene exposure caused reduced peripheral white blood cell (WBC), red blood cell (RBC), platelet (Pit) counts, and hemoglobin (Hgb) concentration. Investigation of the effects of benzene on the expression of FA transport- and beta-oxidation-related enzymes showed that expression of proteins Cpt1a, Crat, Acaa2, Aldh1l2, Acadvl, Crot, Echs1, and Hadha was significantly increased. The ATP levels and mitochondrial membrane potential decreased in mice exposed to benzene. Meanwhile, reactive oxygen species (ROS), hydrogen peroxide (H2O2), and malondialdehyde (MDA) levels were significantly increased in the benzene group. Our results indicate that benzene induces increased expression of FA transport and beta-oxidation enzymes, mitochondrial dysfunction, and oxidative stress, which may play a role in benzene-induced hematotoxicity.