Preclinical immunomodulatory activity of COVIDEX® herbal product developed for supportive treatment of COVID-19 in Uganda

Abstract

The outbreak of the COVID-19 pandemic due to the SARSCoV-2 virus caused international lockdown with devastating effects on global health. In Africa, most people resorted to the use of herbal products for the prevention and treatment COVID-19 related symptoms. In Uganda COVIDEX® herbal product was widely used and is still used against COVID-19 and other viral symptoms of the upper respiratory tract. The product contains extracts of plants with berberine an anti-SARSCoV-2 compound as one of the isoquinoline alkaloids in it. The product is formulated using extracts of Zanthoxylum gilletti, Warburgia ugandensis, and Cymbopogon citratus plants indicated on the product label. This study evaluated the effect of COVIDEX® on modulating immune response in laboratory mice following induction of inflammatory immune response similar to that observed in COVID-19 cases. The mice were given COVIDEX® orally at three dose levels daily for 28 days before induction of inflammation using Lipopolysaccharide administered by intraperitoneal route. After induction of inflammation, the mice spleens were harvested and splenocytes were processed for stimulation studies. COVIDEX® dose of 0.4 ml/kg daily was found to significantly increase the population percentage of CD4+ T cells in the treated group compared to the control (p=0.01) and this effect was dose dependent. COVIDEX® also at doses of 0.1 ml/kg and 0.4 ml/kg significantly suppressed inflammation as indicated by the smaller value of CD4+/IL-10+ in the treated group compared to the control group (p=0.02) and (p=0.02) respectively. However, the percentage of natural killers reduced significantly (p<0.05) at all three dose levels studied. This study indicates that COVIDEX®, is an immunomodulator that may be useful in preventing adverse immune response known as cytokine storm seen in COVID-19 patients.