Terpenoid class of molecules possesses a diverse therapeutic properties and potentials owing to their specific structural features. Prostratin and its derivatives are exemplified in this context to exhibit a variety of biological activities. In this review we discuss in detail the role of prostratin as potential therapeutic and underlying molecular mechanisms by which it accomplishes these activities. Prostratin [13-O-acetyl-12-deoxyphorbol] is a phorbol ester that was first isolated from Strathmore weed Pimelea prostrate, a small endemic New Zealand shrub, and characterized by Hecker in 1976. Structurally, prostratin contains four rings designated as A, B, C and D. Ring A is trans linked to the 7-membered ring B while Ring C is a 6 membered and is cis linked to the cyclopentane ring D. Chemical synthesis of this compound initiated with acidic hydrolysis of phorbol, a tigliane diterpene isolated from croton oil. Prostratin-containing extracts have been used by the Samoan healers to treat individuals with certain medical conditions such as jaundice. Importantly, these treatments are not associated with any significant side effect. Prostratin inhibits HIV-1 infections by down regulating HIV-1 cellular receptors through the activation of protein kinase C (PKC) pathway and reduces the HIV-1 latency. Unlike other phorbol esters that induce carcinogenesis by activating PKC, prostratin does not induce tumors rather has shown tumor suppressing activity. Its ability to induce lytic gene expression supports a role for phorbol-ester regulated signaling pathways in Kaposi's sarcoma associated herpes-virus reactivation.

The global disease burden caused by viral infection has persuaded scientists to develop novel and more effective antiviral drugs. Synthetic antiviral drugs contain substances other than viruses, which have the ability to offer defensive or therapeutic effects in favor of virus-infected host. Medicinal plants, on the other hand, have proven to be potent sources of antiviral agents with some major advantages over conventional drug therapy due to their broad therapeutic potency and limited side effects. Medicinal plants synthesize and preserve a variety of biochemical products possessing potential therapeutic index, aiding elimination/inhibition of viruses. This mini-review provides an insight into medicinal plants and their metabolites explaining their potential role as major alternatives in the treatment of viral infections.

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Seroprevalence of HCV indicates that HCV is found in more than 10% of HBV- or HDV-infected patients worldwide leading to liver disease. Here we show HBV and HDV coinfection association with HCV infected Pakistani patients, study of disease severity, and possible interpretation of associated risk factors in coinfected patients. A total of 730 liver diseased patients were included, out of which 501 were found positive for HCV infection via PCR. 5.1% of patients were coinfected with HBV while 1% were coinfected with HBV and HDV both. LFTs were significantly altered in dually and triply infected patients as compared to single HCV infection. Mean bilirubin, AST, and ALT levels were highest (3.25 mg/dL, 174 IU/L, and 348 IU/L) in patients with triple infection while dual infection LFTs (1.6 mg/dL, 61 IU/L, and 74 IU/L) were not high as in single infection (1.9 mg/dL, 76 IU/L, and 91 IU/L). The most prominent risk factor in case of single (22%) and dual infection (27%) group was “reuse of syringes” while in triple infection it was “intravenous drug users” (60%). It is concluded that HBV and HDV coinfections are strongly associated with HCV infected Pakistani patients and in case of severe liver disease the possibility of double and triple coinfection should be kept in consideration.