14-deoxy-11-12-didehydroandrographolide and 14-deoxyandrographolide

Andrographolide, an ENT-labdane diterpene, has been found to have activities against many viruses. Three free hydroxyls at C-3, C-14, and C-19 are involved in the activities. No stage of action has ever been explored. In this study, the naturally occurring compounds of andrographolide, 14-deoxy-11,12-didehydroandrographolide and 14-deoxyandrographolide, and eight semisynthetic analogues, modified at the three free OHs of andrographolide, were explored for their anti-HSV-1 activities. The concentrations that produced 80 % viable cells were used to test for both pre- and postinfections by using cytopathic effect reduction assays on Vero cell cultures. Three analogues, 14-acetyl-3,19-isopropylideneandrographolide, 14-acetylandrographolide, and 3,14,19-triacetylandrographolide, significantly exhibited preinfection step activity against the virus. For postinfection activity, only 3,19-isopropylideneandrographolide showed absolute inhibition of HSV-1 replication. Meanwhile, andrographolide exhibited slight inhibitory activities of 34.48 ± 6.93 % and 56.90 ± 2.65 % against HSV-1 for pre- and postinfection, respectively. The results confirm that the three hydroxyl moieties play a role in the anti-HSV-1 activity of andrographolide. From the study, it can be concluded that 14-acetyl analogues are good for blocking the viral entry, and 3,19-isopropylideneandrographolide, a cyclic dioxane analogue, is good for exerting postinfection anti-HSV-1 activity.

Topics: Andrographis; Animals; Antiviral Agents; Chlorocebus aethiops; Diterpenes; Herpesvirus 1, Human; Plant Extracts; Plant Leaves; Vero Cells; Virus Internalization; Virus Replication

The immunomodulatory activity of HN-02, an extract containing a mixture of andrographolides (i.e., andrographolide [88 +/- 5 %] plus 14-deoxyandrographolide and 14-deoxy-11,12-didehydroandrographolide together [12 +/- 3 %]) in a pure powder form was evaluated at 1.0, 1.5, and 2.5 mg/kg on different in vivo and in vitro experimental models. In a delayed-type hypersensitivity (DTH) mouse model, potentiation of the DTH reaction was observed after treatment with cyclophosphamide (CYP) and HN-02 individually. However, CYP potentiation of the DTH reaction was reversed by HN-02 pretreatment. Furthermore, HN-02 treatment elevated the depressed hemagglutination antibody (HA) titer and increased the number of plaque-forming cells (PFCs) in the spleen cells of mice that had been treated with CYP and challenged with sheep red blood cells (SRBC). Further, it was also found that HN-02 treatment stimulated phagocytosis in mice. A significant increase in total WBC count and relative weight of spleen and thymus was observed in mice during 30 days of treatment with HN-02. The present experimental findings demonstrate that HN-02 has the ability to enhance immune function, possibly through modulation of immune responses altered during antigen interaction, and to reverse the immunosuppression induced by CYP.

Topics: Andrographis; Animals; Cyclophosphamide; Disease Models, Animal; Diterpenes; Edema; Guinea Pigs; Hypersensitivity, Delayed; Immunologic Factors; Immunosuppressive Agents; Leukocyte Count; Male; Mice; Mice, Inbred Strains; Organ Size; Phagocytosis; Phytotherapy; Plant Preparations; Sheep; Spleen; Thymus Gland