Ginseng, the natural effectual antiviral: Protective effects of Korean Red Ginseng against viral infection

Im, Kyungtaek; Kim, Jisu; Min, Hyeyoung

Human immunodeficiency virus (HIV) belongs to the genus Lentivirus in the family Retroviridae, and two types of HIV have been characterized: HIV-1 and HIV-2 [37] . HIV-1 is the major type of HIV accounting for 95% of infections worldwide and is more virulent and infectious than HIV-2 [38] . HIV-2 is mainly seen in West Africa and has lower infectivity [39, 40] . There are welldefined stages of HIV disease progression from acute infection, clinical latency, and acquired immunodeficiency syndrome AIDS, and an HIV-positive patient is diagnosed with AIDS when his/her CD4þ cell count falls < 200 cells/mm 3 . HIV treatment or highly active antiretroviral therapy (HAART) involves the combination of multiple drugs with different mechanisms of action. HAART can effectively suspend or prevent disease progression from one stage to the next and prolong the lives of HIV-positive patients dramatically by lowering the viral load, maintaining immune system function, and preventing opportunistic infections [7, 41] When combined with zidovudine monotherapy or HAART, RGE has been shown to exert antiviral effects by maintaining CD4þ T cell counts [42e45] and delaying the occurrence of resistance mutation [42, 43, 46] in HIV-1 patients. RGE treatment alone even showed significant antiHIV effects [44,47e49] , implying that RGE intake may become an alternative form of treatment for HIV-1 patients. Negative factor (Nef) is a virulence factor required for achieving high virus load and the progression to AIDS [50] . The 5 0 long terminal repeat (LTR) acts as a promoter of the entire viral genome and stimulates viral genome replication, whereas groupspecific antigen (gag) promotes the formation of fully infectious HIV-1 virions. Interestingly, RGE intake increases the frequency of gross deletions in Nef genes [51e54] and the 5 0 LTR/gag gene [53, 55, 56] , leading to a delay in disease progression and increase of survival rate in HIV-1 patients.