Pranobeks inozyny - działanie cytotoksyczne oraz wpływ na replikację ludzkich wirusów paragrypy (HPIV-2, HPIV-4), enterowirusów (CA16, EV71) i adenowirusów (HAdV-2, HAdV-5) w badaniu in vitro
[Inosine pranobex - cytotoxic activities and effect of on replication of human parainfluenza viruses (HPIV-2, HPIV-4), entroviruses (CA16, EV71) and adenoviruses (HAdV-2, HAdV-5) in vitro]

Streszczenie.

Pranobeks inozyny wykazuje aktywność przeciwwirusową, posiada również potwierdzone w badaniach in vitro i in vivo działanie immunomodulujące. W przeprowadzonym badaniu oceniono wpływ pranobeksu inozyny na redukcję mian zakaźnych wirusów chorobotwórczych dla człowieka (HPIV-2, HPIV-4, CA16, EV71, HAdV-2, HAdV-5). Adenowirusy (HAdV-2, HAdV-5) wykazały najwyższą wrażliwość na przeciwwirusowe działanie pranobeksu inozyny.

Abstract.

Introduction: There are no specific antivirals designed for many viral infections. Inosine pranobex (PI) is a purine nucleoside that is involved in a wide variety of intracellular biochemical processes. The mechanism of action in human body is still unclear but numerous studies have demonstrated that this drug inhibits viral replication and exhibit pleiotropic effect. We evaluated in vitro effect of inosine pranobex (PI) on replication of human viruses: parainfluenza viruses (HPIV-2, HPIV-4), entroviruses A (CA16, EV71) and adenoviruses C (HAdV-2, HAdV-5).Materials and Methods: In the present study, cytotoxic effect of inosine pranobex was assessed using A549 cell line exposed to different concentrations of compound (PI: 50-800 μg/mL) for 48 hours. Cytotoxic effect of inosine pranobex was assessed visually using light, inverted microscopy Olympus CK2 under 400x magnification and by the MTT colorimetric assay. Antiviral effect was estimated according to the reduction of virus titer. The yield reduction assay (YRA), which evaluates the ability of the PI (50-800 μg/mL) to inhibit virus multiplication in cell cultures, was applied. The cytopathic effect of the virus was evaluated 48 h after infection of A549 cell cultures with viruses by means of light, inverted microscopy. The Reed–Muench statistical method was used to determine the 50% end point (IC50) (yield reduction assay, YRA) in the presence of inosine pranobex with the controlled one. Results: There were no morphological changes, as assessed visually, in cell cultures treated with PI. MTT cytotoxicity assay confirmed microscopic observations. The viability of cells in the presence of the tested compounds was average 98, 36 %. After conducting the experiments and analyzing the results we noticed that higher concentrations of PI strongly inhibited multiplication of all viruses. PI weakly reduced the titer of infectious enteroviruses and HPIV-4 as compared with the control. Adenoviruses showed the highest sensitivity to the antiviral activity of PI, however, increasing concentrations of PI up to 800 μg /ml slightly enhanced the antiviral activity of 400 μg/ml PI. Conclusions: Our study demonstrated that inosine pranobex shows no cytotoxic activity on the A549 cell line. In conducted study was observed that adenoviruses (HAdV-2 nd HAdV-5) and HPIV-2 have the highest sensitivity to the antiviral activity of inosine pranobex from all tested viral strains.