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Proceedings of the National Academy of... Dec 2022Activation of endogenous retrotransposons frequently occurs in cancer cells and contributes to tumor genomic instability. To test whether inhibition of...
Activation of endogenous retrotransposons frequently occurs in cancer cells and contributes to tumor genomic instability. To test whether inhibition of retrotranspositions has an anticancer effect, we used treatment with the nucleoside reverse transcriptase inhibitor (NRTI) stavudine (STV) in mouse cancer models, MMTV-HER2/Neu and Th-MYCN, that spontaneously develop breast cancer and neuroblastoma, respectively. In both cases, STV in drinking water did not affect tumor incidence nor demonstrate direct antitumor effects. However, STV dramatically extended progression-free survival in both models following an initial complete response to chemotherapy. To approach the mechanism underlying this phenomenon, we analyzed the effect of NRTI on the selection of treatment-resistant variants in tumor cells in culture. Cultivation of mouse breast carcinoma 4T1 in the presence of STV dramatically reduced the frequency of cells capable of surviving treatment with anticancer drugs. Global transcriptome analysis demonstrated that the acquisition of drug resistance by 4T1 cells was accompanied by an increase in the constitutive activity of interferon type I and NF-κB pathways and an elevated expression of LINE-1 elements, which are known to induce inflammatory responses via their products of reverse transcription. Treatment with NRTI reduced NF-κB activity and reverted drug resistance. Furthermore, the inducible expression of LINE-1 stimulated inflammatory response and increased the frequency of drug-resistant variants in a tumor cell population. These results indicate a mechanism by which retrotransposon desilencing can stimulate tumor cell survival during treatment and suggest reverse transcriptase inhibition as a potential therapeutic approach for targeting the development of drug-resistant cancers.
Topics: Animals; Mice; Reverse Transcriptase Inhibitors; Retroelements; NF-kappa B; Drug Resistance, Neoplasm; Long Interspersed Nucleotide Elements
PubMed: 36449545
DOI: 10.1073/pnas.2213146119 -
Acta Clinica Croatica Mar 2022The aim of this study was to characterize and compare changes in subcutaneous fat in the malar, brachial and crural region in a cohort of HIV-infected patients taking...
The aim of this study was to characterize and compare changes in subcutaneous fat in the malar, brachial and crural region in a cohort of HIV-infected patients taking antiretroviral therapy. This prospective longitudinal study included 77 patients who were selected from the initial cohort evaluated in 2007 and 2008. We examined reversibility of lipoatrophy measured by ultrasound over at least five-year period and factors related to its reversibility. All 46 patients who used stavudine switched from stavudine to another combination. Of 58 patients on zidovudine, 16 (28%) were on a zidovudine based regimen at the second follow up. There was evidence for subcutaneous fat increase in the malar area (p<0.001) and no increase in the brachial and crural areas. Patients who were smokers and had poor adherence to the Mediterranean diet had a thinner malar area at the follow up measurement (p=0.030) and smaller increase in subcutaneous malar fat compared to others (p=0.040). Our study suggested that modest increase of subcutaneous fat in malar area coincided with stopping stavudine and fewer usage of zidovudine. Lifestyle with non-adherence to the Mediterranean diet and smoking were associated with a smaller increase in subcutaneous malar fat.
Topics: Humans; Stavudine; Zidovudine; HIV-Associated Lipodystrophy Syndrome; Cohort Studies; Prospective Studies; Longitudinal Studies; HIV Infections
PubMed: 36398092
DOI: 10.20471/acc.2022.61.01.02 -
Intervirology 2023Pigs are suitable donor species for xenotransplantation and biological materials from these animals are used for this purpose for many years. A major risk of...
INTRODUCTION
Pigs are suitable donor species for xenotransplantation and biological materials from these animals are used for this purpose for many years. A major risk of xenotransplantation is a zoonosis by transspecies transmission of animal viruses. In this regard, porcine endogenous retroviruses (PERVs) are of paramount importance because some of them are able to infect human cells and could induce innate immune responses.
METHODS
Using a replication-competent polytropic PERV-A/C strain, we have analysed the induction of innate immune responses by this virus in human monocytes, monocyte-derived macrophages, and monocyte-derived dendritic cells.
RESULTS
PERV-A/C elevates the expression of the C-X-C motif chemokine 10 (CXCL10) up to 1,000-fold in human monocytes and monocyte-derived primary cells. In comparison to CXCL10, the levels of interferon-β (IFN-β) and interferon-stimulated gene 54 (ISG54) were almost unchanged. Heat-inactivated virus did not induce CXCL10 expression. Neither treatment with the reverse transcriptase inhibitors azidothymidine (AZT) and stavudine (d4T) nor treatment with the integrase inhibitor raltegravir (RAL) reduced the activation levels. Furthermore, depletion of SAM domain and HD domain-containing protein 1 (SAMHD1), a restriction factor that blocks PERV-A/C infection at the level of reverse transcription in these myeloid cells, had no significant effect on the CXCL10 induction level. These results imply that innate immune sensing leading to the strong CXCL10 response occurs at an early step of the replication process and does not require products of reverse transcription. Inhibition of Janus kinases (JAKs) by AT9283 prevented the observed CXCL10 induction by the virus, providing evidence that the JAK-STAT signalling pathway is involved in the CXCL10 response in theses myeloid cells.
CONCLUSION
Our findings highlight PERVs as inducers of the pro-inflammatory chemokine CXCL10 and other innate immune responses in human monocytes and derived cells with potential implications in the context of xenotransplantation.
Topics: Animals; Humans; Chemokine CXCL10; Endogenous Retroviruses; Monocytes; Reverse Transcriptase Inhibitors; Swine; Transplantation, Heterologous; Zoonoses; Viral Zoonoses
PubMed: 36382641
DOI: 10.1159/000527074 -
BMC Infectious Diseases Nov 2022Information on treatment failure (TF) in People living with HIV in a data-poor setting is necessary to counter the epidemic of TF with first-line combined antiretroviral...
BACKGROUND
Information on treatment failure (TF) in People living with HIV in a data-poor setting is necessary to counter the epidemic of TF with first-line combined antiretroviral therapies (cART) in sub-Saharan Africa (SSA). In this study, we examined the risk factors associated with TF in Asmara, Eritrea from 2001 to 2020.
METHODS
A multicenter, retrospective 1:2 matched (by age and gender) case-control study was conducted in four major hospitals in Asmara, Eritrea on adults aged ≥ 18 years who were on treatment for at least 6 months. Cases were patients who fulfills at least one of the WHO therapy failure criterion during the study period. Controls were randomly selected patients on first-line treatment and plasma viral load < 1000 copies/ml in their latest follow-up measurement. Multivariable logistic regression analysis was conducted to identify risk factors for TF. All P-values were 2-sided and the level of significance was set at P < 0.05 for all analyses.
RESULTS
Of the 1068 participants (356 cases; 712 controls), 585 (54.7%) were females. The median age at treatment initiation was 46 years [interquartile range (IQR): 39-51]. Median time to combined antiretroviral therapy (cART) failure was 37 months (IQR = 24-47). In the multivariate analysis, factors associated with increased likelihood of TF included initial nucleoside reverse transcriptase inhibitors (NRTI) backbone (Zidovudine + Lamivudine (AZT + 3TC): adjusted odds ratio (aOR) = 2.70, 95% Confidence interval (CI): 1.65-4.41, P-value < 0.001), (Abacavir + lamivudine (ABC + 3TC): aOR = 4.73, 95%CI: 1.18-18.92, P-value = 0.028], and (Stavudine + Lamivudine (D4T + 3TC): aOR = 5.00; 95% CI: 3.03-8.20, P-value < 0.001) in comparison to Emtricitabine and Tenofovir diproxil fumarate (FTC + TDF). Additional associations included prior exposure to cART (aOR = 2.28, 95%CI: 1.35-3.86; P- value = 0.002), record of sub-optimal drug adherence (aOR = 3.08, 95%CI: 2.22-4.28; P < 0.001), ambulatory/bedridden at presentation (aOR = 1.61, 95%CI: 1.12-4.28; P-value = 0.010), presence of comorbidities (aOR = 2.37; 95%CI: 1.36-4.10, P-value = 0.002), duration of cART (< 5 years: aOR: 5.90; 95% CI: 3.95-8.73, P-value < 0.001), and use of SMX-TMP prophylaxis (aOR = 2.00, 95%CI, 1.44-2.78, P-value < 0.001).
CONCLUSION
Our findings underscore the importance of optimizing cART adherence, diversification of cART regimens, and interventions directed at enhancing early HIV diagnosis, prompt initiations of treatment, and improved patient-focused monitoring of treatment response.
Topics: Adult; Female; Humans; Middle Aged; Male; Lamivudine; Anti-HIV Agents; Retrospective Studies; Case-Control Studies; Eritrea; HIV Infections; Emtricitabine; Anti-Retroviral Agents; Viral Load; Stavudine
PubMed: 36357837
DOI: 10.1186/s12879-022-07797-2 -
Annals of Medicine and Surgery (2012) Sep 2022Regimen change remains a significant challenge towards the achievement of human immunodeficiency virus (HIV) treatment success. In developing countries where limited...
BACKGROUND
Regimen change remains a significant challenge towards the achievement of human immunodeficiency virus (HIV) treatment success. In developing countries where limited treatment options are available, strategies are required to ensure the sustainability and durability of the starting regimens. Nevertheless, information regarding the rate and predictors of regimen change is limited in these settings.
OBJECTIVE
This study was undertaken to determine the prevalence and predictors of changes in ART regimens among patients initiating highly active antiretroviral therapy (HAART) at XX.
MATERIALS AND METHODS
An institutional based retrospective cross-sectional study was conducted among adult naïve HIV patients who had initiated HAART at XX between 2010. Data were extracted by reviewing their medical charts using a pretested structured check-list. The Kaplan-Meier survival analyses were used to describe the probability of ARV regimen changes while Cox proportional hazard regression models were employed to identify the predictors of ARV regimen modifications. Data were analyzed using SPSS version 21 software, and statistical significant was deemed at p < 0.05.
RESULTS
A total of 770 patients were enrolled in this study of these 165 (21.43%) had their ART regimen modified at least once. Drug toxicity was the main reason for regimen change followed by TB comorbidity, and treatment failure. Positive baseline TB symptoms (aHR = 1.63, p = 0.037), and Zidovudine based regimen (aHR = 1.76, p = 0.011) as compared to Stavudine based regimen were at higher risk of ART modification. Conversely, urban residence, baseline World Health organization (WHO) stage 2 as compared to WHO stage 1, baseline CD4 count ≥301 as compared to CD4 count ≤200 were at lower risk of ART modification.
CONCLUSION
The rate of initial HAART regimen change was found to be high. Thus, less toxic and better tolerated HIV treatment options should be available and used more frequently. Moreover, early detection and initiation of ART by the government is highly demanded to maximize the benefit and reduce risk of ART modifications.
PubMed: 36147157
DOI: 10.1016/j.amsu.2022.104303 -
Hepatology Communications Nov 2022There is a heavy burden of liver disease in West Africa. While the role of hepatitis B virus (HBV) infection is well recognized, less is known about the contributing...
There is a heavy burden of liver disease in West Africa. While the role of hepatitis B virus (HBV) infection is well recognized, less is known about the contributing role of liver steatosis and how the two interact in the context of human immunodeficiency virus (HIV) infection. Adults with HIV in Ghana underwent FibroScan measurements to determine prevalence of liver steatosis (expressed as controlled attenuation parameter [CAP]) and fibrosis (expressed as liver stiffness [LS]). We explored contributing factors in linear regression models, including demographics, lifestyle characteristics, medical history, HIV and HBV status, and measurements of metabolic syndrome. Among 329 adults (72.3% women; median age, 47 years), 322 (97.9%) were on antiretroviral therapy (median duration, 8.9 years). CD4 counts were preserved (median, 619 cells/mm ); plasma HIV RNA was fully suppressed in 162 (50.3%) of the treated participants. Cigarette smoking, excessive alcohol consumption, and use of traditional or herbal remedies were uncommon (6.1%, 1.8%, 3.3%, respectively). Largely undiagnosed metabolic syndrome was detected in 87 (26.4%) participants. We obtained readings indicative of ≥S2 steatosis and ≥F2 fibrosis in 43 (13.1%) and 55 (16.7%) participants, respectively. Higher CAP values were associated with metabolic syndrome and longer prior stavudine exposure. Higher LS values were associated with male sex, higher HIV RNA, and higher CAP values. Relative to people without HBV, those with HBV (n = 90) had a similar prevalence of ≥S2 steatosis but a higher prevalence of ≥F2 fibrosis (36.7% vs. 9.2%, p < 0.0001) and concomitant ≥S2 steatosis and ≥F2 fibrosis (9.1% vs. 1.3%, p < 0.001). Conclusion: Both HBV and liver steatosis pose a threat to long-term liver health among people with HIV in West Africa. Urgently required interventions include improving HIV suppression and diagnosing and managing determinants of the metabolic syndrome.
Topics: Adult; Male; Female; Humans; Middle Aged; Coinfection; Hepatitis B virus; Stavudine; Metabolic Syndrome; Liver Cirrhosis; HIV Infections; Fatty Liver; Hepatitis B; HIV; RNA; Ghana
PubMed: 36103301
DOI: 10.1002/hep4.2000 -
Cells Jul 2022Aβ deposition plays a pivotal role in AD pathogenesis by inducing the activation of microglial cells and neuroinflammation. This process is antagonized by...
BACKGROUND
Aβ deposition plays a pivotal role in AD pathogenesis by inducing the activation of microglial cells and neuroinflammation. This process is antagonized by microglia-mediated clearance of Aβ plaques. Activation of the NLRP3 inflammasome is involved in neuroinflammation and in the impairments of Aβ-plaque clearance. On the other hand, stavudine (D4T) downregulates the NLRP3 inflammasome and stimulates autophagy-mediated Aβ-clearing in a THP-1-derived macrophages.
METHODS
We explored the effect of D4T on Aβ autophagy in PBMC from AD patients that were primed with LPS and stimulated with Aβ oligomers in the absence/presence of D4T. We analyzed the NLRP3 activity by measuring NLRP3-ASC complex formation by AMNIS FlowSight and pro-inflammatory cytokine (IL-1β, IL-18 and Caspase-1) production by ELISA. The phosphorylation status of p38, ERK, AKT, p70, and the protein expression of CREB, LAMP2A, beclin-1, Caspase-3 and Bcl2 were analyzed by Western blot.
RESULTS
Data showed that D4T: (1) downregulates NLRP3 inflammasome activation and the production of down-stream pro-inflammatory cytokines in PBMC; (2) stimulates the phosphorylation of AKT, ERK and p70 as well as LAMP2A, beclin-1 and Bcl2 expression and reduces Caspase-3 expression, suggesting an effect of this compound on autophagy; (3) increases phospho-CREB, which is a downstream target of p-ERK and p-AKT, inducing anti-inflammatory cytokine production and resulting in a possible decrease of Aβ-mediated cytotoxicity; and (4) reduces the phosphorylation of p38, a protein involved in the production of pro-inflammatory cytokines and tau hyperphosphorylation.
CONCLUSIONS
D4T reduces the activation of the NLRP3 inflammasome, and it might stimulate autophagy as well as the molecular mechanism that modulates Aβ cytotoxicity, and D4T might reduce inflammation in the cells of AD patients. It could be very interesting to check the possible beneficial effects of D4T in the clinical scenario.
Topics: Alzheimer Disease; Amyloid beta-Peptides; Autophagy; Beclin-1; Caspase 3; Cytokines; Humans; Inflammasomes; Leukocytes, Mononuclear; NLR Family, Pyrin Domain-Containing 3 Protein; Plaque, Amyloid; Proto-Oncogene Proteins c-akt; Proto-Oncogene Proteins c-bcl-2; Stavudine
PubMed: 35883623
DOI: 10.3390/cells11142180 -
Current Research in Chemical Biology 2022Viral diseases are prominent among the widely spread infections threatening human well-being. Real-life clinical successes of the few available therapeutics are... (Review)
Review
Viral diseases are prominent among the widely spread infections threatening human well-being. Real-life clinical successes of the few available therapeutics are challenged by pathogenic resistance and suboptimal delivery to target sites. Nanotechnology has aided the design of functionalised and non-functionalised Au and Ag nanobiomaterials through physical, chemical and biological (green synthesis) methods with improved antiviral efficacy and delivery. In this review, innovative designs as well as interesting antiviral activities of the nanotechnology-inclined biomaterials of Au and Ag, reported in the last 5 years were critically overviewed against several viral diseases affecting man. These include influenza, respiratory syncytial, adenovirus, severe acute respiratory syndromes (SARS), rotavirus, norovirus, measles, chikungunya, HIV, herpes simplex virus, dengue, polio, enterovirus and rift valley fever virus. Notably identified among the nanotechnologically designed promising antiviral agents include , and for influenza, for RSV, for SARS-CoV-2, of a and of for MERS-CoV and SARS-CoV respectively. Others are for rotavirus, for murine norovirus in water, of and of for measles, and for Chikungunya, of and , and for HIV, for HSV, and for dengue while of and analogues displayed potency against enterovirus. The highlighted candidates are recommended for further translational studies towards antiviral therapeutic designs.
PubMed: 35815068
DOI: 10.1016/j.crchbi.2022.100021 -
Molecules (Basel, Switzerland) Jun 2022An improved protocol for the transformation of ribonucleosides into 2',3'-dideoxynucleoside and 2',3'-didehydro-2',3'-dideoxynucleoside derivatives, including the...
An improved protocol for the transformation of ribonucleosides into 2',3'-dideoxynucleoside and 2',3'-didehydro-2',3'-dideoxynucleoside derivatives, including the anti-HIV drugs stavudine (d4T), zalcitabine (ddC) and didanosine (ddI), was established. The process involves radical deoxygenation of xanthate using environmentally friendly and low-cost reagents. Bromoethane or 3-bromopropanenitrile was the alkylating agent of choice to prepare the ribonucleoside 2',3'-bisxanthates. In the subsequent radical deoxygenation reaction, tris(trimethylsilyl)silane and 1,1'-azobis(cyclohexanecarbonitrile) were used to replace hazardous BuSnH and AIBN, respectively. In addition, TBAF was substituted for camphorsulfonic acid in the deprotection step of the 5'--silyl ether group, and an enzyme (adenosine deaminase) was used to transform 2',3'-dideoxyadenosine into 2',3'-dideoxyinosine (ddI) in excellent yield.
Topics: Anti-HIV Agents; Didanosine; Dideoxynucleosides; Stavudine; Zalcitabine; Zidovudine
PubMed: 35807233
DOI: 10.3390/molecules27133993 -
AIDS Research and Human Retroviruses Sep 2022Hypertension (HTN) is a common comorbidity among people with HIV and associated with an increased risk for atherosclerotic cardiovascular disease and chronic kidney... (Randomized Controlled Trial)
Randomized Controlled Trial
Hypertension (HTN) is a common comorbidity among people with HIV and associated with an increased risk for atherosclerotic cardiovascular disease and chronic kidney disease. The relationship of antiretroviral therapy (ART) initiation to incident HTN remains a clinical question. We determined HTN incidence at 48 weeks of follow-up among ART-naive participants without HTN and not taking antihypertensive medications at ART initiation through randomized clinical trials through the AIDS Clinical Trial Group between 1999 and 2011. We assessed the association of baseline characteristics, including randomized ART agents with HTN incidence at 48 weeks using Poisson regression models. Incident HTN was defined as blood pressure ≥130/80 mmHg, or use of antihypertensive medication. Among 2,614 participants, mean age was 37 ± 10 years, 79% male sex, and 36% African American race. After 48 weeks, 839 participants (32%) developed HTN. Receiving a non-nucleoside reverse transcriptase inhibitor (NNRTI) was associated with an increased relative risk (RR) of incident HTN, while the risk was lower for protease inhibitor use. Stavudine and efavirenz were associated with an increased RR of developing HTN, while tenofovir disoproxil fumarate, darunavir/ritonavir, and atazanavir/ritonavir were associated with a decreased risk of developing HTN. Additionally, older age, higher body mass index (BMI), and having hepatitis C were associated with an increased risk for developing HTN, while women and participants with a higher baseline CD4 count were at a decreased risk of developing HTN at 48 weeks. One third of these ART naive participants developed HTN after ART initiation. NNRTIs, notably efavirenz, and stavudine were associated with an increased risk of HTN. Additional factors associated with HTN included traditional factors like older age and higher BMI, and advanced HIV disease (lower CD4 count). (Clinicaltrials.gov: NCT00001137).
Topics: Adult; Alkynes; Anti-HIV Agents; Antihypertensive Agents; Benzoxazines; Cyclopropanes; Female; HIV Infections; Humans; Hypertension; Male; Middle Aged; Risk Factors; Ritonavir; Stavudine
PubMed: 35778856
DOI: 10.1089/AID.2021.0213