Inhibition of cellular invasive parameters in influenza A virus-infected MDCK and Vero cells by a nutrient mixture

Influenza, a long-standing common infection, poses a serious health problem causing significant morbidity and mortality, and imposing substantial economic costs. To date there are no effective antiviral therapies. A unique nutrient mixture (NM), containing lysine, proline, ascorbic acid, green tea extract, N-acetyl cysteine and selenium among other micro nutrients, has been shown to exert a wide range of biochemical and pharmacological effects, among them anti-carcinogenic and anti-atherogenic activity both in vitro and in vivo. In a previous study, NM was found to significantly inhibit influenza virus A associated neuraminidase enzyme as well as production of NP antigen in a dose-dependent manner. Influenza virus A not only infects pulmonary areas, but also manifests in extrapulmonary areas, which require basement membrane disruption by matrix metalloproteinases capable of degrading collagen type IV. This prompted us to study the effect of NM on cellular invasive parameters of virus-infected and non-infected MDCK and Vero cells. NM inhibited extracellular invasive parameters such as MMP-2 and MMP-9 secretion and Matrigel invasion. Results indicated that the relatively non-toxic nutrient mixture tested in this investigation has potential in influenza treatment by not only decreasing viral multiplication in infected cells but also by blocking the enzymatic degradation of the extracellular matrix.