A chemical found in certain green vegetables could protect against viruses that cause illnesses such as Covid and the common cold, according to a new study.
According to scientists, the active chemical, sulforaphane, is found abundantly in cruciferous vegetables such as broccoli, cabbage, kale, and sprouts.
The phytochemical, which already has anti-cancer effects, can inhibit the replication of SARS-CoV-2, the coronavirus that causes COVID-19 and another human coronavirus in cells and mice.
The research team at the Johns Hopkins Children’s Center in the United States warns against buying sulforaphane supplements, saying the research is in its early stages and has yet to conduct human studies.
The researchers used purified synthetic sulforaphane purchased from commercial chemical suppliers in their experiments.
Covid has already killed more than six million people worldwide, and studies have shown that colds cost an estimated $25 billion in economic loss in the United States alone each year.
First identified as a “chemopreventive” compound by a team of scientists at Johns Hopkins decades ago, natural sulforaphane is derived from common food sources.
Previous studies, including those from Johns Hopkins Medicine, have shown that sulforaphane has cancer and infection prevention properties by interfering with certain cellular processes.
Microbiologist Dr Lori Jones-Brando, of Johns Hopkins University School of Medicine, said: ‘When the Covid-19 pandemic began, our multidisciplinary research teams changed our investigations of other viruses and bacteria to focus on a potential treatment for what was then a challenge. new virus for us.
“I was screening several compounds for anti-coronavirus activity and decided to try sulforaphane because it showed modest activity against other microbial agents we are studying.”
In an experiment reported in the journal Nature Communications Biology, the research team first exposed cells to sulforaphane for one to two hours before infecting the cells with SARS-CoV-2 and the common cold coronavirus, HCoV. -OC43.
They found that low concentrations of sulforaphane reduced the replication of six strains of SARS-CoV-2, including the delta and omicron variants, by 50%, as well as that of the coronavirus HCoV-OC43.
The researchers also observed similar results with cells that had been previously infected with the viruses, in which the protective effects of sulforaphane were seen even with an already established viral infection.
The group also looked at the effects of sulforaphane when combined with remdesivir, an antiviral drug used to shorten the recovery of hospitalized adults with COVID-19 infections.
In their findings, remdesivir inhibited 50% of HCoV-OC43 and SARS-CoV-2 replication.
Additionally, the research team reports that sulforaphane and remdesivir interacted synergistically at multiple combination ratios to reduce viral load in cells infected with HCoV-OC43 or SARS-CoV-2 by 50%.
Dr. Alvaro Ordonez said: “Historically, we have learned that combining multiple compounds in a drug regimen is an ideal strategy for treating viral infections.
“The fact that sulforaphane and remdesivir work better combined than alone is very encouraging.”
The researchers then conducted studies in a mouse model of SARS-CoV-2 infection.
They found that giving 30 milligrams of sulforaphane per pound of body weight to mice before infecting them with the virus significantly reduced the body weight loss typically associated with viral infection (7.5% decrease).
Additionally, pretreatment resulted in a statistically significant decrease in viral load, or the amount of virus, in the lungs (17% decrease) and upper respiratory tract (9% decrease) as well as the amount of lesions (29% decrease) compared to infected mice that did not receive sulforaphane.
The compound also decreased inflammation in the lungs, protecting cells from an overactive immune response that appears to be one of the driving factors that has killed many people from Covid-19.
Dr Ordonez said: “What we have found is that sulforaphane is antiviral against the HCoV-OC43 and SARS-CoV-2 coronaviruses while also helping to control the immune response.
“This multifunctional activity makes it an attractive compound to use against these viral infections, as well as those caused by other human coronaviruses.”
The team plans to conduct studies in humans to assess whether sulforaphane may be effective in preventing or treating these infections.
Dr Jones-Brando added: “Despite the introduction of vaccines and other drugs that can have side effects, effective antiviral agents are still needed to prevent and treat COVID-19, especially given the potential effects of novel coronavirus variants occurring in the population.
“Sulforaphane may be a promising less expensive, safe, and readily commercially available treatment.”