Chinese herbal prescription JZ-1 enhances host resistance to herpes simplex virus type 2 through regulating the MRN-ATM-CHK2 DNA damage response

Ethnopharmacological relevance: Genital herpes is a highly prevalent sexually transmitted disease primarily caused by herpes simplex virus type 2 (HSV-2) Infection. The Chinese prescription JZ-1 has demonstrated promising clinical efficacy in treating genital herpes; however, its underlying mechanism remains to be elucidated.

Aim of the study: This study aims to investigate the interaction between HSV-2 Infection and the host DNA damage response (DDR). On this basis, the Antiviral effects and mechanism of JZ-1 on HSV-2 Infection were discussed.

Methods: HSV-2 Infection models were established in HaCat cells and BALB/c mice. The Infection and replication of HSV-2 were assessed using CCK-8 assay, Western blot, immunofluorescence, hematoxylin-eosin staining, and immunohistochemistry. The effects of HSV-2 Infection on MRN complex and its mediated DDR were evaluated through ubiquitination assays and Western blot analysis. Stable HaCat cell lines with MRE11 and Chk2 knockdown or overexpression were constructed using lentiviral transfection. In BALB/c mice, the MRN complex inhibitor mirin was administered to block downstream DDR activation. Under these conditions, HSV-2 Infection was examined to determine the role of the MRN-ATM-CHK2 pathway on it. The optimal concentration of JZ-1 for inhibiting HSV-2 Infection was determined on the basis of no cytotoxic concentration. The expression levels of key DDR proteins and the viral protein were analyzed in HaCat cells and BALB/c mice following JZ-1 intervention using Western blot and immunofluorescence.

Results: Following HSV-2 Infection, HaCat cell viability decreased, accompanied by a significant increase in intracellular viral protein expression (p < 0.001). In BALB/c mice, weight loss, vulvar swelling, hair loss, ulceration, and increased inflammatory infiltration were observed, with elevated viral protein levels in vulvar tissues (p < 0.0001). HSV-2 Infection activated ATM and Chk2, while simultaneously promoting MRE11 degradation in both HaCat cells and mouse vulvar tissues (p < 0.05). MRE11 or Chk2 knockdown in HaCat cells enhanced HSV-2 Infection, whereas MRE11 overexpression suppressed viral Infection. However, Chk2 knockdown reversed the inhibitory effect of MRE11 overexpression (p < 0.05). In BALB/c mice, mirin treatment exacerbated HSV-2 Infection (p < 0.05). JZ-1 significantly inhibited HaCat cell death caused by HSV-2 Infection, with 6.25 mg/mL being the most effective concentration (p < 0.001). In HSV-2-infected mice, JZ-1 gel (2.5 g/mL) effectively alleviated genital herpes symptoms. JZ-1 treatment increased MRE11 expression, enhanced ATM and Chk2 activation, and reduced gD protein levels (p < 0.05). Notably, the Antiviral effect of JZ-1 was partially suppressed when MRN complex function was inhibited (p < 0.05).

Conclusion: The host MRN-ATM-CHK2 DDR pathway serves as a defensive mechanism against HSV-2 Infection by being activated to restrict viral replication. However, HSV-2 Infection simultaneously promotes MRE11 degradation, undermining this protective response. JZ-1 exerts its Antiviral effects by preventing HSV-2-induced MRE11 degradation, thereby enhancing DDR activation and restricting HSV-2 Infection.

DNA damage response (DDR); Genital herpes; Herpes simplex virus type 2 (HSV-2); JZ-1; MRE11.