The Chinese Herbal Prescription JieZe-1 Inhibits Membrane Fusion and the Toll-like Receptor Signaling Pathway in a Genital Herpes Mouse Model

The Chinese herbal prescription JZ-1 promotes extracellular vesicle production and protects against herpes simplex virus type 2 infection in vitro

Objective

Genital herpes, primarily caused by HSV-2 infection, remains a widespread sexually transmitted ailment. Extracellular vesicles play a pivotal role in host-virus confrontation. Recent research underscores the influence of Chinese herbal prescriptions on extracellular vesicle production and composition. This study aims to probe the impact of JieZe-1 (JZ-1) on extracellular vesicle components, elucidating its mechanisms against HSV-2 infection via extracellular vesicles.

Methods

The JZ-1's anti-HSV-2 effects were assessed using CCK-8 assay. Extracellular vesicles were precisely isolated utilizing ultracentrifugation and subsequently characterized through TEM, NTA, and Western Blot analyses. The anti-HSV-2 activity of extracellular vesicles was gauged using CCK-8, Western Blot, and immunofluorescence. Additionally, high-throughput sequencing was employed to detect miRNAs from extracellular vesicles, unraveling the potential antiviral mechanisms of JZ-1.

Results

Antiviral efficacy of JZ-1 was shown in VK2/E6E7, HeLa, and Vero cells. The samples extracted from cell supernatant by ultracentrifugation were identified as extracellular vesicles. In VK2/E6E7 cells, extracellular vesicles from JZ-1 group enhanced cell survival rates and diminished the expression of intracellular viral protein gD, contrasting with the inert effect of control group vesicles. Extracellular vesicles from JZ-1 treated Vero cells demonstrated a weaker yet discernible anti-HSV-2 effect. Conversely, extracellular vesicles of HeLa cells exhibited no anti-HSV-2 effect from either group. High-throughput sequencing of VK2/E6E7 cell extracellular vesicles unveiled significant upregulation of miRNA-101, miRNA-29a, miRNA-29b, miRNA-29c, and miRNA-637 in JZ-1 group vesicles. KEGG pathway analysis suggested that these miRNAs may inhibit PI3K/AKT/mTOR signaling pathway and induce autophagy of host cells to protect against HSV-2. Western blot confirmed the induction of autophagy and inhibition of AKT/mTOR in VK2/E6E7 cells with JZ-1 group extracellular vesicles treatment.

Conclusion

JZ-1 had an anti-HSV-2 efficacy. After JZ-1 stimulation, VK2/E6E7 cells secreted extracellular vesicles which protect host cells from HSV-2 infection. High-throughput sequencing showed that these extracellular vesicles contained a large number of miRNAs targeting PI3K/AKT/mTOR pathway. JZ-1 group extracellular vesicles could inhibit the activation of AKT/mTOR pathway and induce the host cells autophagy.

Integrating network pharmacology and experimental validation to decipher the mechanism of the Chinese herbal prescription JieZe-1 in protecting against HSV-2 infection

CONTEXT

The Chinese herbal prescription JieZe-1 (JZ-1) is effective against HSV-2 (Herpes simplex virus type 2) infection. However, its mechanism remains unclear.

OBJECTIVE

To explore the mechanism of JZ-1 in protecting against HSV-2 infection.

MATERIALS AND METHODS

Using the methods of network pharmacology, the hub components and targets were screened and functionally enriched. We established a genital herpes (GH) mouse model and observe the disease characteristics. Then, the GH mice in different groups (10 per/group) were treated with 20 μL JZ-1 gel (2.5, 1.5, and 0.5 g/mL), acyclovir gel (0.03 g/mL), or plain carbomer gel twice a day. The symptom score, vulvar histomorphology, and virus load were measured. The critical proteins of caspase-1-dependent pyroptosis were analysed by microscopy, co-immunoprecipitation, western blotting, and ELISA. Molecular docking was also performed.

RESULTS

Network pharmacology analysis identified 388 JZ-1 targets related to HSV-2 infection, with 36 hub targets and 21 hub components screened. The TCID₅₀ of HSV-2 was 1 × 10^-7/0.1 mL. JZ-1 gel (2.5 g/mL) can effectively reduce the symptom score (81.23%), viral load (98.42%) and histopathological changes, and significantly inhibit the proteins expression of caspase-1-dependent pyroptosis in GH mice (p< 0.05). The molecular docking test showed a good binding potency between 11 components and caspase-1 or interleukin (IL)-1β.

DISCUSSION AND CONCLUSIONS

The present study demonstrated that JZ-1 protected mice from HSV-2 infection and inhibit the caspase-1-dependent pyroptosis in GH mice. It is of significance for the second development of JZ-1 and the exploration of new drugs.