Indian researchers develop nanozymes that can block HIV reactivation

Researchers at Indian Institute of Science (IISc) here have developed artificial enzymes that y said can successfully block reactivation and replication of Human Immunodeficiency Virus (HIV) in host's immune cells.

Me from vanium pentoxide nanosheets, se "nanozymes" work by mimicking a natural enzyme called glutathione peroxidase that helps reduce oxidative stress levels in host's cells, which is required to keep virus in check, an IISc statement said on Thursday.

study, published in 'EMBO Molecular Medicine, was led by Amit Singh, Associate Professor and Wellcome Trust-DBT India Alliance Senior Fellow at Department of Microbiology & Cell Biology and Centre for Infectious Diseases Research (CIDR), and Govindasamy Mugesh, Professor at Department of Inorganic and Physical Chemistry.

" vantage is that nanozymes are stable inside biological systems and do not mediate any unwanted reactions inside cells," Mugesh said. "y are also quite easy to prepare in lab." re is currently no way to eliminate HIV from a patient's body completely, according to statement.

Anti-HIV drugs are only successful in suppressing virus; y fail at ericating HIV from infected cells. virus hides inside hosts immune cells in a "latent" state and stably maintains its reservoir.

When levels of toxic molecules such as hydrogen peroxide increase in host's cells, leing to a state of increased oxidative stress, virus gets "reactivated" - it emerges from hiding and begins replicating again, it said.

A few years ago, Amit Singh's team developed a biosensor to measure oxidative stress levels in HIV-infected immune cells in real-time, it was stated.

"We found that to come out of latency and reactivate, HIV needs very little oxidative stress," he said.

One way to prevent reactivation is to keep oxidative stress constantly low, which would "lock" virus in a permanent state of latency.

Enzymes such as glutathione peroxidase are essential for this process; y convert toxic hydrogen peroxide to water and oxygen. However, inducing host cells to produce more quantities of se enzymes could disrupt tightly regulated cellular redox machinery.

Around same time, Mugesh's group published a study showing that nanowires me of vanium pentoxide can efficiently mimic activity of glutathione peroxidase.

Singh's lab, refore, decided to collaborate with m.

researchers prepared ultrathin nanosheets of vanium pentoxide in lab and treated HIV-infected cells with m.

sheets were found to reduce hydrogen peroxide just as effectively as natural enzyme and prevent virus from reactivating.

"We found that se nanosheets were having some sort of direct effect where expression of host genes essential for virus reactivation is reduced," said Shalini Singh, first author and Research Associate at CIDR.

When team treated immune cells from HIV-infected patients undergoing antiretroviral rapy (ART) with nanozymes,latency was induced faster and subsequent reactivation was suppressed when rapy was stopped, indicating that combining two was more effective, she ded.

Combining ART with nanozymes also has or vantages.

Some ART drugs can cause oxidative stress as a side effect, which can damage heart or kidney cells, Amit Singh said.

"ding a nanozyme like this can help in reducing side effects caused by such ART drugs." This can improve quality of life of HIV patients undergoing treatment.

Although nanozymes were found to be harmless to normal cells in lab tests, Mugesh said furr studies are needed to understand if y can have or effects once y are introduced inside body.

"Where will y go? Which organs will y enter? How long will y stay in body? We need to look at all se aspects," he ded.