The purpose of this study is to find out anti-HIV-1 reverse transcriptase (RT)/protease (PR) activity and inhibition of virus replication in cell cultures of novel coumarin analogs and determine their structure-activity relationship. Coumarin derivatives have been demonstrated to inhibit the activity of HIV-1 RT/PR in cell free system. It also shows inhibition effects to HIV-1 replication in cell culture. Based on the Chinese traditional pharmacological characteristics and protein three dimension computer aided design, analogs of tetracyclic dipyranocoumarin were synthesized from natural leading compounds. We studied the relationship of antiviral effects and chemical structures via HIV-1 PR/RT enzyme models and cell culture model system. Seven compounds were designed and tested. Several compounds showed anti-HIV-1 activity in varying degrees, especially V0201 showed much higher anti-HIV-1 activity with 3.56 and 0.78 micromol x L(-1) of IC50 against HIV-1 PR/RT and 0.036 micromol x L(-1) against HIV-1 replication in PBMC cultures. V0201 with a novel structure may be a new leading compound. These new compounds are valuable for development of new anti-HIV drugs in the future.

Cycloheximide (CHX) inhibits protein synthesis in most eukaryotic cells and it is a well-known tool commonly used in biochemical research. In this paper, the antiviral spectrum of CHX against several DNA and RNA viruses have been evaluated. CHX showed strong inhibitory activities against several RNA viruses such as HIV-1, influenza viruses, coxsackie B virus, enterovirus (EV71) and several DNA viruses such as HSV and HCMV. Especially the strong inhibitory activities of CHX against coxsackie B virus and enterovirus caught our attention, since effective drugs available in clinic are limited. The SAR of CHX derivatives also has been discussed in the paper. The hydroxyl group at C-2' and carbonyl group at C-2" of CHX are essential for its antiviral activity. And modification to these groups results its derivatives' antiviral activities reduced or lost.

An improved and practical synthesis of racemic 11-demethylcalanolide A [(±)-1] was developed. This improved process involved Pechmann reaction on phloroglucinol with ethyl butyrylacetate to give 5, 7,-dihydroxy-4-n-propylcoumarin(3). Poly phosphoric acid (PPA) catalyzed acylation of compound(3) with crotonic acid, then intramolecular cyclization was achieved simultaneously in one step to afford the key intermediate chromanone(4). A microwave assisted synthetic method preparing chromene(6) using chromenynation of chromanone(4) with 1, 1-diethoxy-methyl-2-butene was conducted. Luche reduction of chromene(6) using NaBH<,4> with CeCl3·7H2O preferably gave (±)-1. The overall yield of this four step synthesis of (±)-1 was around 32% increasing one fold more than that of the previous method. An in vitro investigation showed that (±)-1 exhibited inhibitory activities against both wild-type and drug-resistant HIV-1 in HIV-1 RT and cell culture assay, and significant synergistic effects in combination with AZT, T-20, and indinavir. Its LD50 of acute toxicity in mice by intragastric administration and by intraperitoneal injection were 735.65mg·kg-1 and 525.10mg·kg-1, respectively. The C<,max> and AUC<,0-∞> were 0.54μg·mL-1 and 1.08(μg·mL-1)·h, respectively. The dynamics study of the inhibition of mice sera on HIV-1 RT showed that mice treated with 100mg·kg-1 (±)-1 once intraperitoneally were similar to that of 5mg·kg-1 of known clinical effective anti-HIV-1 drug neverapine. The results suggested that further investigation of the anti-HIV candidate (±)-1 was warranted.

BACKGROUNDTo establish a SAH hydrolase antiviral screening in vitro model for screening of broad spectrum antiviral agents.

METHODSSAH hydrolase was purified from rat livers by (NH4) 2SO4 fractionation, DEAE52,hydroxyapatite and Sephadex G-100 chromatography successively. The activity of SAH hydrolase was estimated by radio labeled substrate in synthesis direction by TLC.

RESULTSPurified SAH hydrolase showed a single band in SDS-PAGE electrophoresis with silver nitrate staining, the apparent molecular weight is 45 000. The Km for adenosine is (6.32 +- 0.17) micromol/L. The IC50 of S-DNPA, a known inhibitor of SAH hydrolase, was 7.6 micromol/L estimated in our system. The structure and activity relationships shown by racemic and regiosomer analogs of S-DHPA indicated that the structural specificity of SAH hydrolase was high. 42 compounds had been screened in the system and no compound showed more inhibitory activity against SAH hydrolase than S-DNPA.

CONCLUSIONSAn in vitro antiviral screening model has been established using SAH hydrolase. It can also be used to study kinetics of enzyme inhibition.

Adenine ; analogs & derivatives ; chemistry ; pharmacology ; Adenosylhomocysteinase ; Animals ; Antiviral Agents ; chemistry ; pharmacology ; Drug Evaluation, Preclinical ; Female ; Hydrolases ; antagonists & inhibitors ; isolation & purification ; metabolism ; In Vitro Techniques ; Liver ; enzymology ; Rats ; Rats, Wistar

ObjectiveTo investigate the efficacy of Bushen Shengxue prescription and Yiqi Yangxue prescription in the treatment of chronic aplastic anemia and the effect on T cell subsets and the expression of T-box expressed in T cells （T-bet） and GATA binding protein 3 （GATA3）. MethodA total of 585 patients with chronic aplastic anemia who were treated in 19 hospitals in China from May 2018 to June 2021 were enrolled. With the prospective， double-blind and randomized control methods， the patients were randomized into three groups： kidney deficiency group， Qi and blood deficiency group， and control group. The three groups were respectively treated with Bushen Shengxue prescription granule， Yiqi Yangxue prescription granule， and Placebo （half the dose of Bushen Shengxue formula granules）. In addition， all of them were given oral cyclosporin and androgen. The treatment lasted 6 months， with 3 months as a course. The blood routine indexes， T cell subsets， and fusion genes T-bet and GATA3 before and after treatment were analyzed， and the safety indexes were monitored. ResultDuring the observation， a total of 75 cases dropped out and 18 were rejected. Finally， 161 cases in the kidney deficiency group， 164 in the Qi and blood deficiency group， and 167 in the control group were included. After 6 months of treatment， the total effective rate was 98.8% （159/161） in the kidney deficiency group， which was higher than the 79.9% （131/164） in the Qi and blood deficiency group （χ²=30.135， P<0.01） and the 61.7% （103/167） in the control group （χ²=70.126， P<0.01）. The total effective rate was higher in the Qi and blood deficiency group than in the control group （χ²=13.232， P<0.01）. After treatment， the hemoglobin （HGB） content increased significantly in three groups （P<0.05） as compared with that before treatment， particularly the kidney deficiency group （P<0.01）. After treatment， the white blood cell （WBC） count and platelet （PLT） count in the kidney deficiency group and the control group increased compared with those in the Qi and blood deficiency group （P<0.01）. There was no specific difference in neutrophils （ANC） after treatment among the three groups. At the same time point， the level of T helper type 1 （Th1） cells， Th1/Th2 ratio （P<0.05）， level of CD4⁺， and CD4⁺/CD8⁺ ratio （P<0.05） were significantly low in the kidney deficiency group among three groups. There was no significant difference in CD19^-， HLA/DR⁺， and CD25⁺ between the kidney deficiency group and the other two groups， but the T-bet of the kidney deficiency group and the control group was lower than that of the Qi and blood deficiency group （P<0.05）. ConclusionBushen Shengxue prescription exerts therapeutic effect on the aplastic anemia by improving the immunoregulatory mechanism， inhibiting the activity of immune system， modulating T cell subsets， suppressing Th1 and CD4⁺， and promoting bone marrow hematopoiesis. Moreover， it is safe with little side effects， which is worthy of further promotion.