Design, synthesis and biological activity of DB02 amino acid derivatives as HIV-1 non-nucleoside reverse transcriptase inhibitors / 药学学报

To improve the stability of amino acid ester derivatives of DB02, a series of 24 amide derivatives of DB02 amino acids as non-nucleoside HIV-1 reverse transcriptase inhibitor were designed and synthesized based on bioisosterism by replacing amino acid ester scaffold with more stable amide bond. The anti-HIV-1 activity of these compounds was evaluated by MTT assay and counting the number of syncytia. Most of the target compounds showed a potential anti-HIV-1 activity, among which compounds 2d, 2i, 2l, 2s, and 2w had better antiviral effect than lead compound DB02, with a therapeutic index > 1 000.00. Finally, the structure-activity relationship of these compounds was discussed, which provided new ideas for the further development of DB02 derivatives.

Design, synthesis, and activity of 5-cyano-2-thiacetyl aromatic pyrimidinone as DENV NS5 RdRp inhibitors / 药学学报

To screen novel anti-dengue virus (DENV) NS5 RdRp enzyme inhibitors, a series of 5-cyano-2-thiacetoaryl pyrimidinone compounds were designed and synthesized by molecular hybridization method with HCV NS5B RdRp inhibitor 3jc and ZIKV NS5 RdRp inhibitor 4w as lead compounds. The anti-DENV activity of these compounds was evaluated by MTT assay and plaque assay and five compounds showed anti-DENV activity. The most active compound 7a'k showed better anti-DENV activity than that of the positive control ribavirin (EC50 = 7.86 μmol·L-1 vs EC50 = 18.07 μmol·L-1), and the other four compounds showed almost the same anti-DENV activity as ribavirin. Finally, the prediction and simulation of the binding mode through molecular provided new ideas for the further development of this new DENV NS5 RdRp inhibitor.

Anti-dengue virus activity of natural podocarpane-type diterpenoid in vitro / 药学学报

Dengue virus (DENV) is the most rapidly transmitted mosquito-borne pathogen, which is the main cause of seasonal outbreaks of dengue fever and dengue hemorrhagic fever in tropical and subtropical regions, and may cause serious life-threatening diseases. There is an urgent need to develop effective vaccines or antiviral therapies. In this paper, we found that a podocarpane-type diterpenoid, (3α,5β,10α)-13-methoxypodocarpa-8,11,13-triene-3,12-diol (MPTD), isolated from the stems and leaves of Aleurites moluccana, showed good effect against DENV. The anti-DENV activity of MPTD against four different DENV serotypes was studied by plaque assay. The cytotoxicity of MPTD in Vero and Huh7 cells was tested by MTT assay. qRT-PCR and Western blot assays were used to investigate the anti-DENV activity of MPTD at RNA and protein levels, respectively. The results showed that MPTD greatly reduced the virus titer in DENV infected Vero cells, and its 50% effective concentration (EC50) for DENV (1–4) were 2.72 ± 0.39, 10.99 ± 5.18, 18.72 ± 0.21, and 0.48 ± 0.28 μmol·L-1, respectively. The results showed that MPTD inhibits DENV RNA level and the expression of E protein. In addition, MPTD may inhibit the early stage of DENV replication and exert antiviral activity. Further studies showed that the inhibitory effect of MPTD against DENV infection is not targeting the viral entry stage. Therefore, MPTD has a significant anti-dengue virus effect, and is an anti-DENV compound with potential application value.

Ciclesonide inhibits Zika virus replication in vitro / 药学学报

Zika virus (ZIKV) is an emerging mosquito-borne virus that is associated with severe congenital brain malformations in the fetus and Guillain-Barré syndrome in adults. However, there are currently no drugs or preventive vaccines approved for ZIKV infection. Here, ciclesonide has been found significantly against ZIKV activity by plaque and cytotoxicity assays in vitro, and its 50% effective concentration (EC50) to ZIKV SZ01 and MR766 are (0.40 ± 0.22) and (1.59 ± 1.08) μmol·L-1, respectively. Its 50% cytotoxic concentration (CC50) to Vero cells are (64.70 ± 7.33) μmol·L-1; Virus yield reduction and Western blot assays showed that ciclesonide can inhibit replication of ZIKV. In addition, ciclesonide can also inhibit the replication of ZIKV in A549 cells; the results of time of drug addition analysis indicated that ciclesonide mainly acts on the ZIKV RNA synthesis stage. Ciclesonide can also inhibit the internalization of ZIKV. These results indicated that ciclesonide is a potential drug against ZIKV.

The anti-ZIKA virus activity of tenofovir disoproxil fumarate in vitro / 药学学报

Tenofovir disoproxil fumarate (TDF) is a nucleoside analogue that has been widely used for clinical treatment of human immunodeficiency virus (HIV) and hepatitis B virus (HBV) infection. The aim of this study was to investigate whether TDF has anti-Zika virus (ZIKV) activity in vitro. The inhibitory effect of TDF on ZIKV was detected by plaque reduction assay. Then, the anti-ZIKV activity of TDF at RNA level and protein level was verified by real time quantitative PCR and Western blot. Finally, MTT assay was used to determine the cytotoxicity of TDF. Our results showed that TDF not only reduced the formation of plaque after ZIKV infection, but also inhibited the replication of ZIKV RNA or expression of ZIKV NS2B protein. The 50% effective concentration (EC50) of TDF in inhibition of ZIKV replication were 14.96-27.47 μmol·L-1, while that of ribavirin was 56.01 ± 12.16 μmol·L-1, which served as the positive control. The cytotoxicity of TDF and ribavirin in Vero cells were very low, with their 50% cytotoxic concentration (CC50) values being greater than 500 μmol·L-1. The therapeutic index of TDF calculated by CC50/EC50 was greater than 18.20, which was significantly higher than that of ribavirin. The results suggest that TDF has good anti-ZIKV activity in vitro and is expected to become a candidate drug for anti-ZIKV therapy.

The study of azvudine activity against dengue viruses in vitro / 药学学报

In this study, azvudine (FNC), hydrochloride salt of azvudine (FNC-HCl) and triphosphate azovudine (FNC-TP) were tested against DENV-Ⅱ recombinant virus (DENV-Ⅱ Luc+). The inhibitory activity of FNC, FNC-HCl and FNC-TP on DENVs were detected by plaque assay. The effect on the expression of DENV-Ⅱ envelope protein E was detected by Western blot; the inhibitory of DENV-Ⅱ viral RNA by compounds was detected by real-time quantitative PCR. MTT assay was used to determine the cytotoxicity of the three compounds on Vero cells. The results showed that FNC, FNC-HCl and FNC-TP inhibited the viral replication by inhibition of renilla luciferase activity of DENV-Ⅱ Luc+. The 50% effective concentration (EC50) of FNC, FNC-HCl and FNC-TP in the inhibition of DENVs replication were from 0.54-25.42 μmol·L-1, while that of ribavirin was 40.78 ±1.02 μmol·L-1 as the positive control. Western blot and real time quantitative PCR results showed that FNC, FNC-HCl and FNC-TP significantly inhibited the expression of DENV-Ⅱ E protein, and the replication of DENV-Ⅱ viral RNA. The 50% cytotoxic concentrations of FNC, FNC-HCl and FNC-TP were all greater than 3 000.00 μmol·L-1. The results suggest that in vitro anti-DENVs activities of FNC, FNC-HCl and FNC-TP are superior to ribavirin, which are expected to become new candidates of anti-DENV drugs.

The combined anti-HIV-1 effect of chloroquine and antiretroviral drugs in vitro / 药学学报

The study is aimed to evaluate the anti-HIV-1 effect of chloroquine in combination with antihuman immunodeficiency virus (HIV) drugs, and inhibition of plasmacytoid dendritic cells (pDC) activation and type I interferon (IFN-I) production by Toll-like receptor 7 (TLR7) agonist stimulation. We investigated the anti-HIV-1ⅢB, HIV-1KM018 activity of chloroquine and chloroquine combined with rategrivir (RAL), enfuvirtide (T-20), indinavir (IDV) and efavirenz (EFV) in vitro by luciferase activity assay system and ELISA method for p24 antigen. We measured the effect of chloroquine on the activation of pDC in combination with RAL and IDV, respectively. Quantitative PCR was used to evaluate the activity of chloroquine in combination with RAL and IDV in the upregulation of interferon (IFN)-α and IFN-β. Chloroquine showed less cytotoxicity to C8166, TZM-bl and PBMC cells, and the 50% cytotoxic concentration values were 85.02 ±0.28, 73.67 ±5.10 and 91.84 ±4.10 μmol·L-1, respectively. The anti-HIV-1ⅢB activity of chloroquine combination with RAL, T-20, IDV and EFV were moderate in synergy, strong in synergy, additive and moderate antagonism, respectively. The anti-HIV-1KM018 activity of chloroquine in combination with RAL, IDV were moderate synergy, minor synergy. There was no significant difference between the chloroquine monotherapy and chloroquine combined with RAL, IDV in the down-regulation of pDC activation and IFN-α, IFN-β expression levels. We have found that chloroquine combined with different anti-HIV drugs represent different degrees of synergism, antagonism or additive anti-HIV-1 effect. Chloroquine in combination with RAL and IDV did not have influence on the inhibitory effect of chloroquine on pDC activation and type I interferon secretion induced by TLR7 agonist. The results suggest that chloroquine may be used to enhance the therapeutic activities of anti-HIV medicines.

The anti-HIV-1 activities of benzophenones non-nucleoside reverse transcriptase inhibitors in vitro / 药学学报

To evaluate the anti-HIV-1 activities of 5 benzophenones non-nucleoside reverse transcriptase inhibitors (NNRTIs) such as DY1203, DY1204, DY1119, DY1208 and DY1209 in vitro, the cytotoxicity of 5 compounds were tested on C8166, MT-4, H9 and PBMC with the MTT assay. The anti-HIV-1 activities of compounds were evaluated on laboratory-adapted strain, drug-resistant strains and primary isolated strains by p24 antigen expression ELISA. The inhibition of HIV-1 recombinant reverse transcriptase activity was assessed by ELISA assay. Among 5 compounds, DY1203 and DY1204 showed low cytotoxicities with CC50 greater than 200 μg·mL-1. DY1119, DY1208 and DY1209 showed strong anti-HIV-1 activities against HIV-1IIIB, HIV-174V, HIV-1RF/V82F/184V, HIV-1NL4-3 gp41(36G) N42S, HIV-1KM018, HIV-1TC-1 and HIV-1Wan. However, NNRTIs drug-resistant strain HIV-1A17 showed different resistance to these compounds. The 5 compounds proved active against HIV-1 recombinant reverse transcriptase. DY1208 is expected to become a new lead compound for its high therapeutic index. The results can provide new information for HIV-1 drug research and promote the development of new HIV-1 drugs.

Wikstroelide M potently inhibits HIV replication by targeting reverse transcriptase and integrase nuclear translocation / 中国天然药物

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.

The anti-HIV activity of three 2-alkylsulfanyl-6-benzyl-3, 4-dihydropyrimidin-4 (3H)-one derivatives acting as non-nucleoside reverse transcriptase inhibitor in vitro / 药学学报

It was recently shown that several new synthetic 2-alkylsulfanyl-6-benzyl-3, 4-dihydropyrimidin-4(3H)-one (S-DABO) derivatives demonstrated anti-HIV-1 activity. Three of the derivatives namely RZK-4, RZK-5 and RZK-6 were used in this study to explore their inhibitory effects on a variety of HIV strains. These compounds at a concentration of 200 microg mL(-1) almost completely inhibited the activity of recombinant HIV-1 reverse transcriptase. All of the three compounds reduced replication of HIV-1 laboratory-derived strains, low-passage clinical isolated strain, and the drug resistant strain. In particular RZK-6 showed potent activity against the HIV-1 drug resistant strain. In general, the antiviral activities are similar in magnitude to nevirapine (NVP), which is a non-nucleoside reverse transcriptase inhibitor approved by FDA. The therapeutic indexes of these compounds were remarkable, ranging from 3704 to 38462 indicating extremely low cytotoxicity. These results suggest that the three S-DABO derivatives in this study have good potential for further development in anti-HIV-1 therapy. It may be particularly useful to target at the non-nucleoside reverse transcriptase inhibitors resistant HIV-1 strain.

Advances in the study of anti-HIV natural compounds derived from traditional Chinese medicines / 药学学报

Anti-HIV drugs still remain as the dominant role in the treatment of acquired immunodeficiency syndrome (AIDS), because no vaccine was found till today. Owing to structural diversity, few side effects, and abundant resources, natural compounds from traditional Chinese medicines and medicinal plants have unique advantages and good potential in prevention and treatment of AIDS. Many researchers have made great efforts in the field of anti-HIV natural compounds, and have found some natural compounds from traditional Chinese medicines with potent anti-HIV activities. These compounds can be classified into the following categories: alkaloids, coumarins, lignans, flavonoids, terpenoids, tannins, polysaccharides, proteins and peptides, and polyphenols. However, most of these researches are performed in vitro, and most natural compounds show weak anti-HIV activities and indefinite acting targets. In the paper, we reviewed some natural compounds derived from traditional Chinese medicines with potent anti-HIV activities in recent years.