Pycnogenol, a procyanidin-rich extract from French maritime pine, inhibits intracellular replication of HIV-1 as well as its binding to host cells.

Department of Molecular Virology, Graduate School, Tokyo Medical and Dental University, Tokyo 113-5819, Japan. .
Japanese journal of infectious diseases (Impact Factor: 1.2). 07/2008; 61(4):279-85.
Source: PubMed

ABSTRACT A procyanidin-rich extract from French maritime pine, Pycnogenol(R) (PYC), is known as an antioxidant that exerts a variety of physiological activities and is widely used in human beings. We report here that PYC inhibits not only human immunodeficiency virus type-1 (HIV-1) binding to host cells, but also its replication after entry in susceptible cells in vitro. Prominent biochemical alterations induced by PYC were the elevated expression of an intracellular antioxidant protein, manganese superoxide dismutase (Mn-SOD), and the inhibition of phosphorylation of the ribosomal S6 protein. Interestingly, ectopic expression of Mn-SOD inhibited HIV-1 replication as well. Inhibition of HIV-1 replication associated with induced expression of Mn-SOD in cells treated with PYC suggests the potential of this natural antioxidant inducer as a new anti-HIV-1 agent.


Available from: Tohti Amet, Apr 28, 2015
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