scholarly journals Structure-Based Design of Novel Dihydroalkoxybenzyloxopyrimidine Derivatives as Potent Nonnucleoside Inhibitors of the Human Immunodeficiency Virus Reverse Transcriptase

1998 ◽  
Vol 42 (12) ◽  
pp. 3225-3233 ◽  
Author(s):  
Elise A. Sudbeck ◽  
Chen Mao ◽  
Rakesh Vig ◽  
T. K. Venkatachalam ◽  
Lisa Tuel-Ahlgren ◽  
...  

ABSTRACT Two highly potent dihydroalkoxybenzyloxopyrimidine (DABO) derivatives targeting the nonnucleoside inhibitor (NNI) binding site of human immunodeficiency virus (HIV) reverse transcriptase (RT) have been designed based on the structure of the NNI binding pocket and tested for anti-HIV activity. Our lead DABO derivative, 5-isopropyl-2-[(methylthiomethyl)thio]-6-(benzyl)-pyrimidin-4-(1H)-one, elicited potent inhibitory activity against purified recombinant HIV RT and abrogated HIV replication in peripheral blood mononuclear cells at nanomolar concentrations (50% inhibitory concentration, <1 nM) but showed no detectable cytotoxicity at concentrations as high as 100 μM.

2003 ◽  
Vol 47 (2) ◽  
pp. 747-754 ◽  
Author(s):  
Yudong Quan ◽  
Bluma G. Brenner ◽  
Maureen Oliveira ◽  
Mark A. Wainberg

ABSTRACT The M184V mutation in human immunodeficiency virus (HIV) reverse transcriptase is associated with high-level resistance to both (−)2′,3′-dideoxy-3′-thiacytidine (3TC) and (−)2′,3′-dideoxy-5-fluoro-3′-thiacytidine as well as low-level resistance to 2′,3′-dideoxyinosine, 2′,3′-dideoxycytidine, and abacavir. This mutation is also associated with diminished HIV replicative fitness as well as several functional changes in enzyme activity, including diminutions in polymerase processivity, pyrophosphorylysis, and nucleotide primer unblocking. Despite the fact that M184V encodes up to 1,000-fold resistance to 3TC, we asked whether this drug might still display some antiviral effect in regard to viruses containing this mutation. Cell-free assays revealed that high concentrations of 3TC triphosphate (i.e., >100 μM) could affect chain termination and/or inhibit purified reverse transcriptase containing the M184V substitution. This effect became more pronounced with elongation of reverse transcriptase products. In newly infected cells (i.e., peripheral blood mononuclear cells), we found that the amount of full-length reverse transcriptase product was diminished in the presence of 2 to 10 μM 3TC, although no decrease in the first product of the reverse transcriptase reaction, i.e., minus strong-stop DNA, was observed. In the presence of two other HIV inhibitors, e.g., nevirapine and indinavir, 3TC exerted additive effects in tissue culture at concentrations only marginally higher than the 50% inhibitory concentration (IC50). Reverse transcriptases cloned from clinical isolates harboring M184V in the context of multidrug resistance had similar IC50 values for 3TC triphosphate compared to reverse transcriptase containing only the M184V mutation. These results suggest that viruses containing M184V can retain a higher degree of sensitivity to 3TC than previously assumed.


2000 ◽  
Vol 44 (8) ◽  
pp. 2093-2099 ◽  
Author(s):  
Brett S. Robinson ◽  
Keith A. Riccardi ◽  
Yi-fei Gong ◽  
Qi Guo ◽  
David A. Stock ◽  
...  

ABSTRACT BMS-232632 is an azapeptide human immunodeficiency virus type 1 (HIV-1) protease (Prt) inhibitor that exhibits potent anti-HIV activity with a 50% effective concentration (EC50) of 2.6 to 5.3 nM and an EC90 of 9 to 15 nM in cell culture. Proof-of-principle studies indicate that BMS-232632 blocks the cleavage of viral precursor proteins in HIV-infected cells, proving that it functions as an HIV Prt inhibitor. Comparative studies showed that BMS-232632 is generally more potent than the five currently approved HIV-1 Prt inhibitors. Furthermore, BMS-232632 is highly selective for HIV-1 Prt and exhibits cytotoxicity only at concentrations 6,500- to 23,000-fold higher than that required for anti-HIV activity. To assess the potential of this inhibitor when used in combination with other antiretrovirals, BMS-232632 was evaluated for anti-HIV activity in two-drug combination studies. Combinations of BMS-232632 with either stavudine, didanosine, lamivudine, zidovudine, nelfinavir, indinavir, ritonavir, saquinavir, or amprenavir in HIV-infected peripheral blood mononuclear cells yielded additive to moderately synergistic antiviral effects. Importantly, combinations of drug pairs did not result in antagonistic anti-HIV activity or enhanced cytotoxic effects at the highest concentrations used for antiviral evaluation. Our results suggest that BMS-232632 may be an effective HIV-1 inhibitor that may be utilized in a variety of different drug combinations.


2005 ◽  
Vol 49 (8) ◽  
pp. 3474-3482 ◽  
Author(s):  
Katsunori Takashima ◽  
Hiroshi Miyake ◽  
Naoyuki Kanzaki ◽  
Yoshihiko Tagawa ◽  
Xin Wang ◽  
...  

ABSTRACT TAK-220 is a member of a novel class of chemokine receptor antagonists and is highly specific to CCR5, as determined by receptor binding and calcium mobilization assays. The compound selectively inhibited coreceptor-mediated entry of human immunodeficiency virus type 1 (HIV-1) into host cells and HIV-1 infection mediated by CCR5. TAK-220 inhibited the replication of six CCR5-using (R5) HIV-1 clinical isolates in peripheral blood mononuclear cells (PBMCs) with a mean 90% effective concentration of 13 nM. The anti-HIV-1 activity of TAK-220 was not affected by addition of high concentrations of human serum. It equally inhibited R5 HIV-1 replication in PBMCs obtained from eight different donors, irrespective of the levels of viral production. Furthermore, the anti-HIV-1 activity of TAK-220 was found to be subtype independent. TAK-220 did not induce CCR5 internalization but blocked the binding of two monoclonal antibodies that recognize the second extracellular loop of CCR5 in CCR5-expressing cells. These results suggest that TAK-220 selectively inhibits R5 HIV-1 replication by interfering with coreceptor-mediated entry of the virus into host cells. At a dose of 5 mg/kg of body weight, TAK-220 showed oral bioavailabilities of 9.5 and 28.9% in rats and monkeys, respectively. Thus, TAK-220 is a promising candidate for the treatment of HIV-1 infection.


2021 ◽  
Vol 6 (3) ◽  
pp. p26
Author(s):  
Silas David Emmanuel ◽  
I. M. Bugaje ◽  
S. M. Mohammmad

Purposes: The unprecedented and sequence through which an estimate of 25 million lives have gone to their early grave yard through Acquired Immune-deficiency Syndrome HIV/AIDS can never be quantified; since, when it was first describes in 1981. In 2017/2018 by (UNAIDS) it was estimated globally for about 36.9millions people were living with Human, Immunodeficiency Virus (HIV) so to say. Henceforth the progress made in the field of treatment in the form of Antiretroviral Therapy (ART) disease has not been fully ascertain for the cure of HIV/AIDS; except, perpetual clinical suppressions. Thus, the current challenges that man kinds faces with the used of perpetual intake of antiretroviral therapy (clinical suppression)/artificial vaccine is un-justifiable. However, search for HIV therapy have open a new chapter in the search for novel drugs from Kaduna Polytechnic procedure. This review focuses on vitamins, antioxidant, mineral and supplement as sources of in-hibitors or eradications for human immunodeficiency virus type-1 (HIV) reverse transcriptase. Objective: To assess whether vitamins, antioxidant, minerals supplement are effective and safe in eradicating mortality and morbidity among populace with HIV infection. Selection criteria: Randomized control trials were selected that compared the effect of vitamins (A, C, D, E, K,), antioxidant, minerals and supplement with regard to treatment measures in HIV infected persons. Methods: To prevent authors bias, based on a systematic search of literature; anti-HIV reverse transcriptase activity of some plant’s species like those of Eucalyptus leaves, Garlic fresh fruits, Baobab leaves, aloe vera, neem leaves, moringa leaves, bitter leaves etc. respectively. Thus, these medicinal plants contain an appreciable or above values antioxidant compound or photochemical like those of Phenolic, anthraquinone, tannin, falconoid, terpenoid, lignin, coumarins etc. respectively. Contrarywise, these phytochemical compounds have been exploited traditionally for the cure of many diseases as well as inhibition of viral replication/transcription. Further investigations have shared more light through which phytochemicals compounds inhibit virus replication either during the viral entry inside the host cell or during their replication. Originality: in view of the current investigation or to accelerate drug discovery and innovation, this review recommends the urgent need to tap into the enrich locally available endogenous knowledge of putative anti- HIV/AIDS, photochemical and their derivatives, (reverse pharmacology, determine pan assay, interferences compounds, microbial enzyme metabolites relationship and their mechanisms to treat virial diseases.


2004 ◽  
Vol 48 (10) ◽  
pp. 3834-3844 ◽  
Author(s):  
Charlene S. Dezzutti ◽  
V. Nicole James ◽  
Artur Ramos ◽  
Sharon T. Sullivan ◽  
Aladin Siddig ◽  
...  

ABSTRACT A standardized protocol was used to compare cellular toxicities and anti-human immunodeficiency virus type 1 (HIV-1) activities of candidate microbicides formulated for human use. The microbicides evaluated were cellulose acetate phthalate (CAP), Carraguard, K-Y plus nonoxynol-9 (KY-N9), PRO 2000 (0.5 and 4%), SPL7013 (5%), UC781 (0.1 and 1%), and Vena Gel, along with their accompanying placebos. Products were evaluated for toxicity on cervical and colorectal epithelial cell lines, peripheral blood mononuclear cells (PBMCs), and macrophages (MΦ) by using an ATP release assay, and they were tested for their effect on transepithelial resistance (TER) of polarized epithelial monolayers. Anti-HIV-1 activity was evaluated in assays for transfer of infectious HIV-1 from epithelial cells to activated PBMCs and for PBMC and MΦ infection. CAP, Carraguard, PRO 2000, SPL7013, and UC781 along with their placebos were 20- to 50-fold less toxic than KY-N9 and Vena Gel. None of the nontoxic product concentrations disrupted the TER. Transfer of HIV-1Ba-L from epithelial cells to PBMCs and PBMC and MΦ infection with laboratory-adapted HIV-1Ba-L and HIV-1LAI isolates were inhibited by all products except Carraguard, KY-N9, and Vena Gel. KY-N9, Vena Gel, and Carraguard were not effective in blocking PBMC infection with primary HIV-1A, HIV-1C, and HIV-1CRF01-AE isolates. The concordance of these toxicity results with those previously reported indicates that our protocol may be useful for predicting toxicity in vivo. Moreover, our systematic anti-HIV-1 testing provides a rational basis for making better informed decisions about which products to consider for clinical trials.


2008 ◽  
Vol 82 (6) ◽  
pp. 2813-2820 ◽  
Author(s):  
Anvita Kumar ◽  
Andrew Zloza ◽  
Randall T. Moon ◽  
Jeffrey Watts ◽  
Allan R. Tenorio ◽  
...  

ABSTRACT The Wnt/β-catenin pathway is involved in cell functions governing development and disease. In modeling postentry restriction of human immunodeficiency virus (HIV) replication in astrocytes, we reported that part of this natural resistance to productive replication of HIV in astrocytes involved expression of proteins of the Wnt/β-catenin signaling pathway. We determined here whether induction of β-catenin signaling in peripheral blood mononuclear cells (PBMCs) can modulate HIV replication. Given that lithium is an inducer of β-catenin signaling, we used it as a tool to determine the impact of β-catenin signaling on HIV replication in PBMCs. We demonstrated that lithium inhibited the replication of T-tropic and primary isolates of HIV by >90% and did so in noncytotoxic/noncytostatic concentrations and in a β-catenin-dependent manner. Specifically, inhibiting β-catenin signaling by transfection of dominant-negative mutant constructs to either T-cell factor 4, the downstream effector of Wnt signaling, or β-catenin, the central mediator of this pathway, abrogated the ability of lithium to inhibit HIV replication. Moreover, when Wnt/β-catenin signaling was inhibited, the level of HIV replication was enhanced by fourfold. To confirm the in vivo relevance of the β-catenin pathway in repressing HIV replication, we evaluated HIV-positive antiretroviral therapy-naive patients who were on lithium therapy. These patients demonstrated a reduction in viral load, which increased as the dose of lithium was reduced. Collectively, these data indicate that β-catenin signaling is an intrinsic molecular pathway restricting HIV replication in PBMCs.


Blood ◽  
1995 ◽  
Vol 85 (8) ◽  
pp. 2114-2123 ◽  
Author(s):  
A Foli ◽  
MW Saville ◽  
MW Baseler ◽  
R Yarchoan

The cytokines interleukin-12 (IL-12) and IL-4 play important roles in the development of Th1-like (type-1) and Th2-like (type-2) T-cell responses, respectively, and there is evidence that type-1/type-2 T helper imbalances are important in the pathogenesis of human immunodeficiency virus (HIV) disease. With this background, we examined the effects of these cytokines on HIV replication. Neither stimulated HIV replication in fresh peripheral blood mononuclear cells (PBMC). However, in prestimulated PBMC, IL-12, and to a greater extent, IL-4 as well as IL-2, induced production of HIV p24 antigen over 7 days of culture (no cytokine 3,900 x/divided by 1.31 [GM x/divided by SEM] pg/mL; IL-12, 34,300 x/divided by 1.39 pg/mL; IL-4, 283,000 x/divided by 1.14 pg/mL; and IL-2, 328,000 x/divided by 1.31 pg/mL). Neither IL-12- nor IL-4-induced HIV replication was attributable to induction of IL-1, IL-2, tumor necrosis factor (TNF)-alpha, or TNF-beta. Both IL-12- and IL-4-induced HIV replication was associated with selective loss of the CD4+ subset in stimulated cultures. IL-4 stimulated HIV replication in monocyte/macrophages, while IL-12 had little or no effect in these cells. Finally, HIV replication stimulated by IL-12 or IL-4 was inhibited by dideoxynucleosides. Thus, IL-12 and IL-4 enhance HIV replication and HIV-induced cell death in prestimulated PBMC. Through killing of the CD4+ T cells stimulated by these cytokines, this may result in inappropriate type-1/type-2 responses in HIV-infected patients and contribute to their Th1 immunodeficiency.


2002 ◽  
Vol 46 (8) ◽  
pp. 2687-2691 ◽  
Author(s):  
A. A. Pilon ◽  
J. J. Lum ◽  
J. Sanchez-Dardon ◽  
B. N. Phenix ◽  
R. Douglas ◽  
...  

ABSTRACT Inhibition of human immunodeficiency virus type 1 reverse transcriptase (RT) by both nucleoside and nonnucleoside RT inhibitors profoundly inhibits virus replication. Nucleoside RT inhibitors are known to be toxic, but there is little information regarding the toxicities of nonnucleoside RT inhibitors (NNRTI). We demonstrate that efavirenz (an NNRTI) induces caspase- and mitochondrion-dependent apoptosis of Jurkat T cells and human peripheral blood mononuclear cells. The clinical relevance of these observations is not yet clear.


Sign in / Sign up

Export Citation Format

Share Document