Hydrogen sulphide can help in fight against HIV, find IISc scientists

BENGALURU: At present, the treatment of HIV is done via Combined antiretroviral therapy (cART), which is used to suppress the virus and not cure the person infected. However, the method is said to come with negative effects such as oxidative stress (where pro-oxidants are more than antioxidants, excess of which causes chronic disorders or organ failure). Also, mitochondria in cells stop functioning properly (resulting in fatigue), with the cART. Stopping cART is not an option because the virus that is latent may reactivate in the absence of therapy, as per researchers.

Scientists at the Indian Institute of Science have made a key discovery that will help in comprehensive antiretroviral therapy against HIV to deal with effects such as oxidative stress in the body and dysfunction of mitochondria. They have found that hydrogen sulphide (H2S) gas is effective in suppressing the virus.

In earlier studies, the researchers at the lab created a tool to measure oxidative stress in cells infected with HIV, and also tried to find the effects of an antioxidant nanozyme.

Considering H2S also functions as an antioxidant molecule, the team’s present research was to check if their earlier findings on oxidative stress and HIV could be used to show the effect of H2S on HIV infection.

Experiments were set up for this — new model systems were built, different techniques such as colorimetric and fluorometric were used to detect H2S which is elusive if conventional methods are used.

“We observed a direct effect of H2S on suppressing HIV reactivation and replication along with all its other beneficial effects, such as maintenance of mitochondrial health and dissipation of oxidative stress in our [cellular] models,” confirmed Amit Singh, Associate Professor in MCB/CIDR and corresponding author of this study, in a note.

He said, "This opens the door to supplementing cART with chemical donors of H2S to lock HIV in a state of deep latency, potentially improving the lives of millions infected with the virus. Since H2S donors are already undergoing clinical trials for other diseases, they can quickly be repurposed for HIV treatment."

The most common class of H2S donors employed in biological studies are sodium hydrosulfide (NaSH) and sodium sulfide (Na2S).

The research done by the Department of Microbiology and Cell Biology (MCB) and the Centre for Infectious Disease Research (CIDR) at IISc, in collaboration with Bangalore Medical College and Research Institute, was published in the journal eLife.