Acyclovir or Aβ42 peptides attenuate HSV-1-induced miRNA-146a levels in human primary brain cells

Human brains harbor herpes simplex virus type-1 (HSV-1) DNA, which normally remains quiescent throughout many decades of life. HSV-1 is associated with viral encephalopathy and with the amyloid beta 42 (Aβ42) peptide-enriched lesions that characterize Alzheimer's disease neuropathology. Here we report that infection of human neuronal-glial cells in primary co-culture with HSV-1 induces an irregular hypertrophy of human neuronal-glial cell bodies, an induction of HSV-1 DNA polymerase, and an up-regulation of micro-RNA-146a associated with altered innate-immune responses. Presence of the antiviral acyclovir or soluble Aβ42 peptide significantly attenuated these neuropathological responses. The inhibitory effects of Aβ42 peptide were also observed in an HSV-1-infected CV-1 cell-based viral plaque assay. The results suggest that soluble Aβ42 peptide can invoke non-pathological and anti-viral effects through inactivation of an HSV-1 challenge to human brain cells by simple viral sequestration, viral destruction, or by complex neurogenetic mechanisms.