Cobinamide is a strong and versatile antioxidant that overcomes oxidative stress in cells, flies, and diabetic mice

• Published in: PNAS nexus Vol. 1; no. 4; p. pgac191
• Main Authors: Chang, Stephen, Tat, John, China, Shyamsundar Pal, Kalyanaraman, Hema, Zhuang, Shunhui, Chan, Adriano, Lai, Cassandra, Radic, Zoran, Abdel-Rahman, Engy A, Casteel, Darren E, Pilz, Renate B, Ali, Sameh S, Boss, Gerry R
• Format: Journal Article
• Language: English
• Published: England Oxford University Press 01.09.2022
• Subjects: Antioxidants; Biological, Health, and Medical Sciences; Chemical properties; Health aspects; Vitamin B12; United States; Egypt; cobinamide; antioxidant; diabetes; oxidative stress
• ISSN: 2752-6542; 2752-6542
• DOI: 10.1093/pnasnexus/pgac191

Increased oxidative stress underlies a variety of diseases, including diabetes. Here, we show that the cobalamin/vitamin B analog cobinamide is a strong and multifaceted antioxidant, neutralizing superoxide, hydrogen peroxide, and peroxynitrite, with apparent rate constants of 1.9 × 10 , 3.7 × 10 , and 6.3 × 10 M s , respectively, for cobinamide with the cobalt in the +2 oxidation state. Cobinamide with the cobalt in the +3 oxidation state yielded apparent rate constants of 1.1 × 10 and 8.0 × 10 M s for superoxide and hydrogen peroxide, respectively. In mammalian cells and , cobinamide outperformed cobalamin and two well-known antioxidants, imisopasem manganese and manganese(III)tetrakis(4-benzoic acid)porphyrin, in reducing oxidative stress as evidenced by: (i) decreased mitochondrial superoxide and return of the mitochondrial membrane potential in rotenone- and antimycin A-exposed H9c2 rat cardiomyocytes; (ii) reduced JNK phosphorylation in hydrogen-peroxide-treated H9c2 cells; (iii) increased growth in paraquat-exposed COS-7 fibroblasts; and (iv) improved survival in paraquat-treated flies. In diabetic mice, cobinamide administered in the animals' drinking water completely prevented an increase in lipid and protein oxidation, DNA damage, and fibrosis in the heart. Cobinamide is a promising new antioxidant that has potential use in diseases with heightened oxidative stress.