The Mechanism Underlying the Protective Effects of Tannic Acid Against Isoproterenol-Induced Myocardial Fibrosis in Mice

• Published in: Frontiers in pharmacology 2020-05, Vol.11, p.716-716
• Main Authors: Ma, Donglai, Zheng, Bin, Du, Huiru, Han, Xue, Zhang, Xuan, Zhang, Jianping, Gao, Yonggang, Sun, Shijiang, Chu, Li
• Format: Article
• Language: English
• Subjects: cardioprotection; isoproterenol; myocardial fibrosis; nuclear factor κB; Pharmacology; tannic acid; toll-like receptor 4
• ISSN: 1663-9812; 1663-9812
• DOI: 10.3389/fphar.2020.00716

Tannic acid (TA) belongs to a class of complex water-soluble polyphenolic derivatives that show anticarcinogenic, antiinflammatory, antioxidant, and scavenging activities. Here, we investigate the protective effects of TA against isoproterenol (ISO)-induced myocardial fibrosis (MF) in mice. Mice received TA and ISO dosing and were sacrificed 48 h later. The activities of creatine kinase (CK), creatine kinase-MB (CK-MB), lactate dehydrogenase (LDH), and mitochondria enzymes were measured. Cardiac histopathology was done using H&E, Sirius red, and Masson’s Trichrome staining. Immunohistochemical staining was applied to indicate changes in B-cell lymphoma-2 (Bcl-2), Bcl-2-associated X protein (Bax), and basic fibroblast growth factor (bFGF) protein expressions in cardiac tissue. RT-PCR was used to measure the expression of atrial and brain natriuretic peptides (ANP and BNP, respectively), c-fos, and c-jun. Western blotting was used to measure the expression of nuclear factor-κB (NF-κB) p65, phosphorylated NF-κB p65), toll-like receptor 4 (TLR4), p38, phosphorylated p38, Bax, Bcl-2, and caspase-3. Compared to the ISO group, the TA group had reduced levels of TLR4, p38, p-p38, NF-κB (p65), p-NF-κB (p-p65), caspase-3, Bax, and Bcl-2, as well as CK, CK-MB, and LDH. These results indicate that TA protects against ISO-induced MF, possibly through its ability to suppress the TLR4-mediated NF-κB signaling pathway.