The within-host fitness of HIV-1 increases with age in ART-naïve HIV-1 subtype C infected children.

As the immune system develops with age, children combat infections better. HIV-1, however, targets an activated immune system, potentially rendering children increasingly permissive to HIV-1 infection as they grow. How HIV-1 fitness changes with age in children is unknown. Here, we estimated the within-host basic reproductive ratio, R0, a marker of viral fitness, in HIV-1 subtype C-infected children in India, aged between 84 days and 17 years. We measured serial viral load and CD4 T cell counts in 171 children who initiated first-line ART. For 25 children, regular and frequent measurements provided adequate data points for analysis using a mathematical model of viral dynamics to estimate R0. For the rest, we used CD4 counts for approximate estimation of R0. The viral load decline during therapy was biphasic. The mean lifespans of productively and long-lived infected cells were 1.4 and 27.8 days, respectively. The mean R0 was 1.5 in children aged < 5 years, increased with age, and approached 6.0 at 18 years, close to 5.8 estimated previously for adults. The tolerogenic immune environment thus compromises HIV-1 fitness in young children. Early treatment initiation, when the R0 is small, will likely improve viral control, in addition to suppressing the latent reservoir.

Viral evolution in the cell-associated HIV-1 DNA during early ART can lead to drug resistance and virological failure in children.

Using cell-associated DNA and cell-free RNA of human immunodeficiency virus type-1 (HIV-1), we investigated the role of drug-resistant viral variants that emerged during early antiretroviral therapy (ART) in determining virological outcome. This case-control study compared virologic nonresponder children (two viral loads [VLs] ≥ 200 copies/mL within 2 years of ART) and responder children (two VLs < 200 copies/mL after six months of ART) infected with HIV-1 initiated on nonnucleoside reverse-transcriptase inhibitor (NNRTI)-based ART. The partial reverse-transcriptase gene of HIV-1 in cell-associated DNA was genotyped using next-generation sequencing (NGS; Illumina; threshold 0.5%; at baseline and month six of ART) and in cell-free RNA (concurrently and at virological failure; VL > 1000 copies/mL at ≥ 12 months of ART) using the Sanger method. Among 30 nonresponders and 37 responders, baseline differences were insignificant while adherence, VL, and drug resistance mutations (DRMs) observed at month six differed significantly ( P ≥ 0.05). At month six, NGS estimated a higher number of DRMs compared with Sanger (50% vs 33%; P = 0.001). Among the nonresponders carrying a resistant virus (86.6%) at virological failure, 26% harbored clinically relevant low-frequency DRMs in the cell-associated DNA at month six (0.5%-20%; K103N, G190A, Y181C, and M184I). Plasma VL of > 3 log 10 copies/mL (AOR, 30.4; 95% CI, 3.3-281; P = 0.003) and treatment-relevant DRMs detected in the cell-associated DNA at month six (AOR, 24.2; 95% CI, 2.6-221; P = 0.005) were independently associated with increased risk for early virological failure. Our findings suggest that treatment-relevant DRMs acquired in cell-associated DNA during the first six months of ART can predict virological failure in children initiated on NNRTI-based ART.

High Abundance of genus Prevotella in the gut of perinatally HIV-infected children is associated with IP-10 levels despite therapy.

Perinatal HIV infection is characterized by faster HIV disease progression and higher initial rate of HIV replication compared to adults. While antiretroviral therapy (ART) has greatly reduced HIV replication to undetectable levels, there is persistent elevated inflammation associated with HIV disease progression. Alteration of gut microbiota is associated with increased inflammation in chronic adult HIV infection. Here, we aim to study the gut microbiome and its role in inflammation in treated and untreated HIV-infected children. Examination of fecal microbiota revealed that perinatally infected children living with HIV had significantly higher levels of genus Prevotella that persisted despite ART. These children also had higher levels of soluble CD14 (sCD14), a marker of microbial translocation, and IP-10 despite therapy. The Prevotella positively correlated with IP-10 levels in both treated and untreated HIV-infected children, while genus Prevotella and species Prevotella copri was inversely associated with CD4 count. Relative abundance of genus Prevotella and species Prevotella copri showed positive correlation with sCD14 in ART-suppressed perinatally HIV-infected children. Our study suggests that gut microbiota may serve as one of the driving forces behind the persistent inflammation in children despite ART. Reshaping of microbiota using probiotics may be recommended as an adjunctive therapy along with ART.

Energetics of Excitatory and Inhibitory Neurotransmission in Aluminum Chloride Model of Alzheimer's Disease: Reversal of Behavioral and Metabolic Deficits by Rasa Sindoor.

Alzheimer's disease (AD) is an age-related neurodegenerative disorder, characterized by progressive loss of cognitive functions and memory. Excessive intake of aluminum chloride in drinking water is associated with amyloid plaques and neurofibrillary tangles in the brain, which are the hallmark of AD. We have evaluated brain energy metabolism in aluminum chloride (AlCl3) mouse model of AD. In addition, effectiveness of Rasa Sindoor (RS), a formulation used in Indian Ayurvedic medicine, for alleviation of symptoms of AD was evaluated. Mice were administered AlCl3 (40 mg/kg) intraperitoneally once a day for 60 days. The memory of mice was measured using Morris Water Maze test. The 13C labeling of brain amino acids was measured ex vivo in tissue extracts using 1H-[13C]-NMR spectroscopy with timed infusion of [1,6-13C2]glucose. The 13C turnover of brain amino acids was analyzed using a three-compartment metabolic model to derive the neurotransmitter cycling and TCA cycle rates associated with glutamatergic and GABAergic pathways. Exposure of AlCl3 led to reduction in memory of mice. The glutamatergic and GABAergic neurotransmitter cycling and glucose oxidation were found to be reduced in the cerebral cortex, hippocampus, and striatum following chronic AlCl3 treatment. The perturbation in metabolic rates was highest in the cerebral cortex. However, reduction in metabolic fluxes was higher in hippocampus and striatum following one month post AlCl3 treatment. Most interestingly, oral administration of RS (2 g/kg) restored memory as well as the energetics of neurotransmission in mice exposed to AlCl3. These data suggest therapeutic potential of RS to manage cognitive functions and memory in preclinical AD.

Sub-therapeutic nevirapine concentration during antiretroviral treatment initiation among children living with HIV: Implications for therapeutic drug monitoring.

Nevirapine, a component of antiretroviral therapy (ART) in resource-limited settings, known for auto-induction of metabolism, is initiated at half therapeutic dose until day 14 ('lead-in period'), and subsequently escalated to full dose. However, studies have shown that this dosing strategy based on adult studies may not be appropriate in children, given that younger children have higher drug clearance rates. In this prospective cohort study, we studied trough plasma nevirapine levels by high performance liquid chromatography (HPLC) at days 7, 14 (lead-in period) and 28 (full dose period) after ART initiation amongst HIV-1 infected children initiating nevirapine-based ART in southern India. Among the 20 children (50% male, median age 9 years) included in the study, sub-therapeutic trough plasma nevirapine concentration (<4µg/ml) was seen in 65% (13/20) of children during the lead-in period within two weeks of ART initiation and among 10% of children at 4 weeks during full-dose nevirapine. Adherence was documented as ≥95% in all children by both caregiver self-report and pill count. Median nevirapine concentrations achieved at week 1 was 4.8 µg/ml, significantly lower than 8 µg/ml, the concentration achieved at week 4 (p = 0.034). Virological failure at one year of ART was observed in six children, and was not associated with median nevirapine concentration achieved during week 1, 2 or 4. We conclude that the dose escalation strategy currently practiced among young children living with HIV-1 resulted in significant subtherapeutic nevirapine concentration (≤4µg/ml) during the lead-in period. We call for a closer look at pediatric-focused dosing strategies for nevirapine initiation in young children. Further studies to establish age-appropriate threshold nevirapine concentration are warranted in young children to corroborate the role of therapeutic drug monitoring in predicting virological outcome.