Study finds mushroom enzyme effective in combating hepatitis C

A team of CSIC researchers has co-discovered that an enzyme present in the white mushroom (Agaricus bisporus), called tyrosine, has antiviral activity against the hepatitis C virus by means of an inhibition mechanism different from that of the usual drugs. This finding, made in vitro and published in the journal Pharmaceuticals, could contribute to the development of promising therapeutic agents.

“In this case, the inhibition of virus proteases occurs through a biocatalytic mechanism based on a selective hydroxylation of surface tyrosines of proteins involved in virus replication,” explains José Miguel Palomo, CSIC researcher at the Institute of Catalysis and Petrochemistry (ICP-CSIC), who co-led the study in collaboration with researchers Olga Abián and Adrián Velázquez from the University of Zaragoza.

From testing this method in vitro, the researchers have shown that mushroom tyrosinase, and particularly an isoform, a variant of the enzyme itself, are efficient at micromolar concentrations, i.e., one millionth of the mass of the molecules. They completely inhibit hepatitis C virus replication in human liver cells. In fact, the isoform has an antiviral capacity up to ten times higher than that of the commercial drug Ribavirin, currently used in combination in many treatments.

In addition, the results obtained in this study have shown that the enzymes extracted directly from the mushroom do not present toxicity in liver cells, so they could be used as proteins for the treatment of hepatitis C infection. Therefore, this tyrosinase preparation could become a promising therapeutic agent. “We could provide a very low-cost drug for the treatment of the virus, which could be used as a substitute or in combination with other drugs,” says Palomo.

The researcher insists on the great cost reduction that the manufacture of a drug based on mushroom tyrosinases would entail, as current treatments cost around 60,000 euros per patient.

The research group seeks to make further progress and develop in vivo trials of this type of compound to demonstrate its potential as a drug. To this end, they say, they are open to collaboration with other interested research groups, as well as with private companies.

The research, already patented, continues with the aim of obtaining a drug against hepatitis C, which in 2019 killed about 290,000 people, according to data from the World Health Organization (WHO). In addition, the research group points out that this new viral inhibition mechanism of mushroom tyrosinase is postulated as a broad-spectrum pharmacological agent.