Antiviral Action of Tryptanthrin Isolated from Strobilanthes cusia Leaf against Human Coronavirus NL63

Biomolecules

Hung-Rong Yen¹  Su-Hua Huang²  Chia-Lin Lee³  Yu-Ping Lin⁴  Young-Sheng Chang⁵  Yu-Chi Tsai⁶  Cheng-Wen Lin⁶ 

[1] Chinese Medicine Research Center, China Medical University, Taichung, 40402, Taiwan;Department of Biotechnology, Asia University, Wufeng, Taichung 41354, Taiwan;Department of Cosmeceutics, China Medical University, Taichung 40402, Taiwan;Department of Medical Laboratory Science and Biotechnology, China Medical University, Taichung 40402, Taiwan;Graduate Institute of Biomedical Sciences, College of Medicine, China Medical University, Taichung 40402, Taiwan;PhD Program for Health Science and Industry, College of Health Care, China Medical University, Taichung 40402, Taiwan;

关键词: strobilanthes cusia;    tryptanthrin;    indigodole b;    human coronavirus nl63;    antiviral;    virucidal;   

DOI  :  10.3390/biom10030366

来源: DOAJ

【 摘 要 】

Strobilanthes cusia (Nees) Kuntze is a Chinese herbal medicine used in the treatment of respiratory virus infections. The methanol extract of S. cusia leaf contains chemical components such as β-sitosterol, indirubin, tryptanthrin, betulin, indigodole A, and indigodole B that have diverse biological activities. However, the antiviral action of S. cusia leaf and its components against human coronavirus remains to be elucidated. Human coronavirus NL63 infection is frequent among immunocompromised individuals, young children, and in the elderly. This study investigated the anti-Human coronavirus NL63 (HCoV-NL63) activity of the methanol extract of S. cusia leaf and its major components. The methanol extract of S. cusia leaf effectively inhibited the cytopathic effect (CPE) and virus yield (IC₅₀ = 0.64 μg/mL) in HCoV-NL63-infected cells. Moreover, this extract potently inhibited the HCoV-NL63 infection in a concentration-dependent manner. Among the six components identified in the methanol extract of S. cusia leaf, tryptanthrin and indigodole B (5aR-ethyltryptanthrin) exhibited potent antiviral activity in reducing the CPE and progeny virus production. The IC₅₀ values against virus yield were 1.52 μM and 2.60 μM for tryptanthrin and indigodole B, respectively. Different modes of time-of-addition/removal assay indicated that tryptanthrin prevented the early and late stages of HCoV-NL63 replication, particularly by blocking viral RNA genome synthesis and papain-like protease 2 activity. Notably, tryptanthrin (IC₅₀ = 0.06 μM) and indigodole B (IC₅₀ = 2.09 μM) exhibited strong virucidal activity as well. This study identified tryptanthrin as the key active component of S. cusia leaf methanol extract that acted against HCoV-NL63 in a cell-type independent manner. The results specify that tryptanthrin possesses antiviral potential against HCoV-NL63 infection.

【 授权许可】

Unknown