Euphopias G - J, macrocyclic diterpenes with anti-zika virus activity from Euphorbia helioscopia L.

Four new diterpenoids (1-4) and sixteen known diterpenoids (5-20) were purified from the whole plant of Euphorbia helioscopia L. Compounds 1 and 2 were rhamofolane diterpenoids with a 5/7/6 tricyclic systems, compound 3 was a lathyranes diterpenoid, and compound 4 was a jathophanes diterpenoid. The isolated compounds were tested for their cytotoxicity and anti-Zika virus properties, and compounds 9 and 15 showed low cytotoxicity and strong anti-Zika virus properties with EC50 2.63 and 5.94 µM, respectively. Further, the inhibitory effects of compounds on protein levels were determined using Western blotting and immunofluorescence assays.

Gastrodin Alleviates Vascular Dementia in a 2-VO-Vascular Dementia Rat Model by Altering Amyloid and Tau Levels.

Vascular dementia (VaD) is the second most common type of dementia and has become a major public health challenge as the global population ages. VaD is caused by cerebrovascular disease, and most patients with VaD have been reported to also have Alzheimer's pathologies, which is the formation of neurofibrillary tangles and amyloid plaques that are mainly composed of hyperphosphorylated Tau and amyloid ß (Aß) respectively. However, the mechanisms of VaD are not completely understood, and very few drugs are available to treat this condition. Gastrodin (Gas) is the main bioactive component of the traditional Chinese herbal plant named Tian Ma (Gastrodia elata), and it has been used to treat neurasthenia in the clinical practice of Chinese Medicine for many years. Here, we hypothesize that Gas alleviates VaD in a rat model of permanent bilateral common carotid artery occlusion (2-VO)-induced VaD. Based on the results of the Morris water maze test and attention set shift test, either 22.5 or 90 mg/kg/day Gas improved the executive dysfunction and memory impairment of 2-VO rats following an intragastric administration for 4 weeks. Both 22.5 and 90 mg/kg/day Gas reduced Aß1-40 and Aß1-42 plaques in plasma and hippocampus of 2-VO rats. Mechanistically, in 2-VO rats, treatment with Gas (90 mg/kg/day) suppressed Aß plaque deposition by decreasing the hippocampus levels of phosphorylated Tau. Thus, Gas ameliorated the cognitive deficits of 2-VO rats by inhibiting the abnormal phosphorylation of Aß and Tau.

Wikstroelide M potently inhibits HIV replication by targeting reverse transcriptase and integrase nuclear translocation.

AIM: To evaluate the anti-HIV activity and mechanism of action of wikstroelide M, a daphnane diterpene from Daphne acutiloba Rehder (Thymelaeaceae). METHODS: The anti-HIV activities of wikstroelide M against different HIV strains were evaluated by cytopathic effect assay and p24 quantification assay with ELISA. The inhibitory effect of wikstroelide M on HIV reverse transcription was analyzed by real-time PCR and ELISA. The effect of wikstroelide M on HIV-1 integrase nuclear translocation was observed with a cell-based imaging assay. The effect of wikstroelide M on LEDGF/p75-IN interaction was assayed by molecular docking. RESULTS: Wikstroelide M potently inhibited different HIV-1 strains, including HIV-1IIIB, HIV-1A17, and HIV-19495, induced a cytopathic effect, with EC50 values ranging from 3.81 to 15.65 ng·mL⁻¹. Wikstroelide M also had high inhibitory activities against HIV-2ROD and HIV-2CBL-20-induced cytopathic effects with EC50 values of 18.88 and 31.90 ng·mL⁻¹. The inhibitory activities of wikstroelide M on the three HIV-1 strains were further confirmed by p24 quantification assay, with EC50 values ranging from 15.16 to 35.57 ng·mL⁻¹. Wikstroelide M also potently inhibited HIV-1IIIB induced cytolysis in MT-4 cells, with an EC50 value of 9.60 ng·mL⁻¹. The mechanistic assay showed that wikstroelide M targeted HIV-1 reverse transcriptase and nuclear translocation of integrase through disrupting the interaction between integrase and LEDGF/p75. CONCLUSION: Wikstroelide M may be a potent HIV-1 and HIV-2 inhibitor, the mechanisms of action may include inhibition of reverse trascriptase activity and inhibition of integrase nuclear translocation through disrupting the interaction between integrase and LEDGF/p75.

Potent anti-HIV activities and mechanisms of action of a pine cone extract from Pinus yunnanensis.

The anti-HIV activities of a pine cone extract (YNS-PY-F) from Pinus yunnanensis have been evaluated, and its mechanisms of action were also explored. The pine cone extract, YNS-PY-F, potently inhibited HIV-1(IIIB), HIV-1(RF), HIV-1(A17), HIV-1(AO18) and HIV-2(ROD) and induced cytopathic effect in C8166 cells with EC50 values of 0.96 µg/mL, 1.53 µg/mL, 0.88 µg/mL, 7.20 µg/mL and 6.17 µg/mL, respectively. The quantification of a p24 production assay showed that YNS-PY-F significantly inhibited the acute replication of HIV-1(IIIB), HIV-1RF, HIV-1(A17) and HIV-1(AO18) in C8166 cells. An MTT assay showed that YNS-PY-F also significantly inhibited the HIV-1(IIIB) induced cytolysis in MT-4 cells with an EC50 value of 2.22 µg/mL. The mechanism assays showed that YNS-PY-F had potent inhibitory effects on the fusion between infected cells and uninfected cells, and the activity of HIV-1 reverse transcriptase, with EC50 values of 7.60 µg/mL and 4.60 µg/mL, respectively. Overall, these data suggest that the pine cone extract from Pinus yunnanensis has potent inhibitory activities against HIV-1(IIIB), HIV-1(RF), RT inhibitor-resistant strains HIV-1(A17) and HIV-1(AO18), and HIV-2(ROD), and its anti-HIV mechanisms include inhibition of HIV entry and inhibition of reverse transcriptase activity.