Short communication: The relationship between mitochondrial dysfunction and insulin resistance in HIV-infected children receiving antiretroviral therapy

Health-Related Physical Fitness Evaluation in HIV-Diagnosed Children and Adolescents: A Scoping Review

BACKGROUND

Health-related physical fitness has been widely used to investigate the adverse effects of HIV infection/ART in children and adolescents. However, methods/protocols and cut-points applied for investigating health-related physical fitness are not clear. The aim of this scoping review was to map the literature to identify gaps in knowledge regarding the methods/protocols and cut-points.

METHODS

A scoping review, following the Joana Briggs Institute (JBI) guidelines, was conducted through ten major databases. Search followed the PCC strategy to construct block of terms related to population (children and adolescents), concept (health-related physical fitness components) and context (HIV infection).

RESULTS

The search resulted in 7545 studies. After duplicate removal, titles and abstracts reading and full text assessment, 246 studies were included in the scoping review. Body composition was the most investigated component (n = 244), followed by muscular strength/endurance (n = 23), cardiorespiratory fitness (n = 15) and flexibility (n = 4). The World Health Organization growth curves, and nationals' surveys were the most reference values applied to classify body composition (n = 149), followed by internal cut-points (n = 30) and cut-points developed through small populations (n = 16). Cardiorespiratory fitness was classified through cut-points from three different assessment batteries, as well as cut-points developed through studies with small populations, muscular strength/endurance and flexibility were classified through the same cut-points from five different assessment batteries.

CONCLUSIONS

The research on muscular strength/endurance, cardiorespiratory fitness and flexibility has been scarcely explored. The lack of studies that investigated method usability as well as reference values was evidenced.

High prevalence of low high-density lipoprotein cholesterol and insulin resistance among children and adolescents living with HIV in Uganda: harbinger for metabolic syndrome?

BACKGROUND

Antiretroviral therapy-associated adverse effects and comorbidities are still pervasive in people living with HIV, especially metabolic syndrome (MetS). We investigated the age-dependent prevalence of components of MetS and insulin resistance in children and adolescents living with HIV (CALWH).

METHODS

A cross-sectional pilot study of CALWH treated at the Baylor Uganda Clinical Centre of Excellence in Kampala, Uganda, May to August 2021. The primary outcome of MetS was defined by both the International Diabetes Federation (IDF) and the Adult Treatment Panel (ATP III) criteria. We estimated the prevalence of MetS and its components for all participants and by the stratification factors.

RESULTS

We enrolled 90 children and adolescents, aged 6 to <10 years (n = 30), 10 to <16 years (n = 30), and ≥ 16 to <19 years (n = 30). Fifty-one percent were females. The estimated prevalence of MetS was 1.11% (1 of 90) using either IDF or ATPIII criteria for all participants, and 3.33% in the oldest age group. Notably, while only one among study participants met the criterion based on having central obesity or blood pressure, over 55% of participants had one or more IDF component, with 47% having low high-density lipoprotein (HDL) cholesterol. Two participants (6.67%) in the group aged 10 to <16 years met one of the definitions for insulin resistance (IR) using the Homeostatic Model Assessment (HOMA-IR) index. For every 1-year increase in age, HOMA-IR index increased by 0.04 (95% confidence interval: 0.01-0.08; p = 0.02).

CONCLUSIONS

With increasing survival of CALWH into adulthood, lifetime exposure to ART, the frequency of MetS in this population may rise, increasing the lifetime risk for associated health problems. There is a need to study the natural history of MetS in CALWH to inform preventative and treatment interventions as needed.

Glucose metabolism continuous deteriorating in male patients with human immunodeficiency virus accepted antiretroviral therapy for 156 weeks

BACKGROUND

The dynamic characteristics of glucose metabolism and its risk factors in patients living with human immunodeficiency virus (PLWH) who accepted primary treatment with the efavirenz (EFV) plus lamivudine (3TC) plus tenofovir (TDF) (EFV + 3TC + TDF) regimen are unclear and warrant investigation.

AIM

To study the long-term dynamic characteristics of glucose metabolism and its contributing factors in male PLWH who accepted primary treatment with the EFV + 3TC + TDF regimen for 156 wk.

METHODS

This study was designed using a follow-up design. Sixty-one male treatment-naive PLWH, including 50 cases with normal glucose tolerance and 11 cases with prediabetes, were treated with the EFV + 3TC + TDF regimen for 156 wk. The glucose metabolism dynamic characteristics, the main risk factors and the differences among the three CD4+ count groups were analyzed.

RESULTS

In treatment-naive male PLWH, regardless of whether glucose metabolism disorder was present at baseline, who accepted treatment with the EFV + 3TC + TDF regimen for 156 wk, a continuous increase in the fasting plasma glucose (FPG) level, the rate of impaired fasting glucose (IFG) and the glycosylated hemoglobin (HbA1c) level were found. These changes were not due to insulin resistance but rather to significantly reduced islet β cell function, according to the homeostasis model assessment of β cell function (HOMA-β). Moreover, the lower the baseline CD4+ T-cell count was, the higher the FPG level and the lower the HOMA-β value. Furthermore, the main risk factors for the FPG levels were the CD3+CD8+ cell count and viral load (VL), and the factors contributing to the HOMA-β values were the alanine aminotransferase level, VL and CD3+CD8+ cell count.

CONCLUSION

These findings provide guidance to clinicians who are monitoring FPG levels closely and are concerned about IFG and decreased islet β cell function during antiretroviral therapy with the EFV + 3TC + TDF regimen for long-term application.

Associations of FGF21 and GDF15 with mitochondrial dysfunction in children living with perinatally-acquired HIV: A cross-sectional evaluation of pediatric AIDS clinical trials group 219/219C

BACKGROUND

In persons living with HIV, mitochondrial disease (MD) is difficult to diagnose, as clinical signs are non-specific with inconsistent patterns. Fibroblast growth factor 21 (FGF21) and growth differentiation factor 15 (GDF15) are mitokines elevated in MD patients without HIV, and associated with cardiometabolic comorbidities in adults living with HIV. We assessed relationships of these biomarkers with MD in children living with perinatally-acquired HIV infection (CPHIV).

SETTING

Cross-sectional study of CPHIV from Pediatric ACTG 219/219C classified by Mitochondrial Disease Criteria (MDC) that defines scores 2-4 as "possible" MD.

METHODS

Each case with MDC equaling 4 (MDC4; n = 23) was matched to one randomly selected control displaying no MDC (MDC0; n = 23) based on calendar date. Unmatched cases with MDC equaling 3 (MDC3; n = 71) were also assessed. Plasma samples proximal to diagnoses were assayed by ELISA. Mitokine distributions were compared using Wilcoxon tests, Spearman correlations were calculated, and associations with MD status were assessed by conditional logistic regression.

RESULTS

Median FGF21 and GDF15 concentrations, respectively, were highest in MDC4 (143.9 and 1441.1 pg/mL), then MDC3 (104.0 and 726.5 pg/mL), and lowest in controls (89.4 and 484.7 pg/mL). Distributions of FGF21 (paired Wilcoxon rank sum p = 0.002) and GDF15 (paired Wilcoxon rank sum p<0.001) differed in MDC4 vs MDC0. Mitokine concentrations were correlated across all participants (r = 0.33; p<0.001). Unadjusted odds ratios of being MDC4 vs MDC0 were 5.2 [95% confidence interval (CI): 1.06-25.92] for FGF21 and 3.5 (95%CI: 1.19-10.25) for GDF15. Relationships persisted after covariate adjustments.

CONCLUSION

FGF21 and GDF15 levels may be useful biomarkers to screen for CPHIV with mitochondrial dysfunction.

Gradual increasing dyslipidemia in treatment-naive male patients with human immunodeficiency virus and treated with tenofovir plus lamivudine plus efavirenz for 3 years

INTRODUCTION

Since the development of antiretroviral therapy (ART) with TDF plus 3TC plus EFV, this specific regimen has not been studied enough with long-term lipid and uric acid monitoring.

METHODS

A prospective follow-up cohort study was performed. Sixty-one treatment-naive male patients with human immunodeficiency virus (HIV) were divided into three groups based on their baseline CD4+ cell count (26, 12, and 23 patients in the < 200, 200 to 350, and > 350 groups, respectively). The lipid and purine metabolism parameters of the patients over 144 weeks were analyzed.

RESULT

Within 144 weeks, TG, LDL-c, TC and HDL-c gradually increased, especially TC and HDL-c (P = 0.001, 0.000, respectively). Moreover, the percentages of hyper-cholesterolemia, hyper LDL cholesterolemia, hyper-triglyceridemia and low HDL cholesterolemia also gradually increased, especially low HDL cholesterolemia significantly increased (P = 0.0007). The lower the baseline CD4+ cell counts were, the higher the TG levels and the lower the TC, LDL-c and HDL-c levels were. But there was significant difference of only baseline LDL-c levels between the three groups (P = 0.0457). No significant difference of the UA level and the percentages of hyperuricemia was found between the different follow-up time point groups or between the three CD4+ cell counts groups (all P > 0.05). The risk factors for dyslipidemia included age, anthropometric parameters and follow-up weeks, and for hyperuricemia was virus load.

CONCLUSIONS

Gradual increasing dyslipidemia was found in male patients with human immunodeficiency virus primarily treated with tenofovir plus lamivudine plus efavirenz for 3 years. There-fore lipid metabolism parameters should be closely monitored during long-term ART with the TDF plus 3TC plus EFV regimen.

Mitochondrial changes associated with viral infectious diseases in the paediatric population

Infectious diseases occur worldwide with great frequency in both adults and children, causing 350,000 deaths in 2017, according to the latest World Health Organization reports. Both infections and their treatments trigger mitochondrial interactions at multiple levels: (i) incorporation of damaged or mutated proteins into the complexes of the electron transport chain; (ii) impact on mitochondrial genome (depletion, deletions and point mutations) and mitochondrial dynamics (fusion and fission); (iii) membrane potential impairment; (iv) apoptotic regulation; and (v) generation of reactive oxygen species, among others. Such alterations may result in serious adverse clinical events with considerable impact on the quality of life of the children and could even cause death. Herein, we use a systematic review to explore the association between mitochondrial alterations in paediatric infections including human immunodeficiency virus, cytomegalovirus, herpes viruses, various forms of hepatitis, adenovirus, T-cell lymphotropic virus and influenza. We analyse how these paediatric viral infectious processes may cause mitochondrial deterioration in this especially vulnerable population, with consideration for the principal aspects of research and diagnosis leading to improved disease understanding, management and surveillance.

Mitochondrial Dysfunction and Insulin Resistance in Pubertal Youth Living with Perinatally Acquired HIV

Mitochondrial dysfunction (MD) is linked to cardiometabolic complications, such as obesity and insulin resistance (IR), the frequencies of which are higher in adults living with HIV infection and receiving combination antiretroviral therapies (ARV). ARV-treated youth living with perinatally acquired HIV infection (YLPHIV) may be especially susceptible to IR due to long-term exposure to both factors. Medical histories, fasting blood chemistry panels, and mitochondrial function in banked peripheral blood mononuclear cells (PBMCs) were assessed in eligible YLPHIV from the Pediatric HIV/AIDS Cohort Study (PHACS)/Adolescent Master Protocol (AMP) Mitochondrial Determinants Component cohort, stratified by Homeostatic Model Assessment of IR (HOMA-IR) score: case (score ≥4, n = 39) or control (score <4, n = 105). PBMCs were sources for mitochondrial (mt) DNA copies/cell; mtRNA transcript levels of oxidative phosphorylation (OXPHOS) subunits NADH dehydrogenases 1 and 6, and cytochrome B; and enzymatic activities of OXPHOS Complexes I (CI) and IV (CIV). Logistic regression models were fit to estimate the odds of IR case diagnosis, adjusted for sex, race/ethnicity, body mass index (BMI) z-score, and Tanner stage. IR cases were similar to controls by age, sex, and race/ethnicity. Cases had higher median levels of peak HIV viral load, lactate, pyruvate, triglycerides, and BMI z-scores. OXPHOS CI enzymatic activity was lower in cases (log₁₀ 1.62 vs. 1.70) and inversely correlated with HOMA-IR score (r = -0.157, p = .061), but did not associate with IR in adjusted models. Fully adjusted models indicated associations of nadir CD4% [odds ratio (OR) = 0.95, 95% confidence intervals (CIs) = 0.90-1.00] or peak HIV load (OR = 3.48, 95% CIs = 1.70-10.79) with IR. IR in YLPHIV was strongly associated with morphometrics, but early virologic and immunologic factors may also influence MD.

Factors Associated With Insulin Resistance in Adults With HIV Receiving Contemporary Antiretroviral Therapy: a Brief Update

PURPOSE OF REVIEW

This narrative review summarizes recent data on factors associated with insulin resistance (IR) in adults with HIV, including contemporary antiretroviral therapy (ART).

RECENT FINDINGS

IR remains common in persons with HIV, even those receiving contemporary ART. Generalized and abdominal obesity and ectopic fat are correlates of IR, and emerging data have identified associations with biomarkers of inflammation and immune activation. Small studies suggest associations between mitochondria and IR. In ART-naïve individuals, IR increased within 4 weeks of starting ART in persons receiving contemporary boosted protease inhibitors or an integrase inhibitor. The importance of IR in non-diabetic persons with HIV will continue to grow as the population ages and obesity increases. Non-invasive estimates of IR appear to perform well in persons with HIV, but clinically relevant cutoffs are uncertain. Unexpected metabolic effects of newer HIV integrase inhibitors have been reported; thus, careful observation for and studies of IR are still warranted.

Changes in insulin sensitivity over time and associated factors in HIV-infected adolescents

OBJECTIVE

To compare prevalence of insulin resistance between perinatally HIV-infected (PHIV+) and perinatally HIV-exposed, but uninfected adolescents (PHEU), determine incidence of and contributory factors to new and resolved cases of insulin resistance in PHIV+, and evaluate glucose metabolism.

DESIGN

Cross-sectional design for comparison of prevalence among PHIV+ and PHEU. Longitudinal design for incidence and resolution of insulin resistance among PHIV+ at risk for these outcomes.

METHODS

The source population was adolescents from pediatric HIV clinics in the United States and Puerto Rico participating in the Pediatric HIV/AIDS Cohort Study, an ongoing prospective cohort study designed to evaluate impact of HIV infection and its treatment on multiple domains in preadolescents and adolescents. Insulin resistance was assessed by homeostatic model assessment of insulin resistance. Those with incident insulin resistance underwent 2-h oral glucose tolerance test and HbA1c. Baseline demographic, metabolic, and HIV-specific variables were evaluated for association with incident or resolved insulin resistance.

RESULTS

Unadjusted prevalence of insulin resistance in PHIV+ was 27.3 versus 34.1% in PHEU. After adjustment for Tanner stage, age, sex, and race/ethnicity, there was no significant difference between groups. Factors positively associated with developing insulin resistance included female sex, higher BMI z score, and higher waist circumference; those associated with resolving insulin resistance included male sex and lower BMI z score.

CONCLUSION

Prevalence of insulin resistance in PHIV+ and PHEU was substantially higher than that reported in HIV-uninfected nonoverweight youth, but similar to that in HIV-uninfected obese youth. Factors associated with incident or resolved insulin resistance among PHIV+ were similar to those reported in HIV-negative obese youth. However, a contributory role of HIV infection and/or its treatment to the incident risk of insulin resistance cannot be excluded.

Insulin resistance in HIV-infected youth is associated with decreased mitochondrial respiration

OBJECTIVE

To identify relationships between insulin resistance (IR) and mitochondrial respiration in perinatally HIV-infected youth.

DESIGN

Case-control study.

METHODS

Mitochondrial respiration was assessed in perinatally HIV-infected youth in Tanner stages 2-5, 25 youth with IR (IR+) and 50 without IR (IR-) who were enrolled in the Pediatric HIV/AIDS Cohort Study. IR was defined as a homeostatic model of assessment for IR value at least 4.0. A novel, high-throughput oximetry method was used to evaluate cellular respiration in peripheral blood mononuclear cells. Unadjusted and adjusted differences in mitochondrial respiration markers between IR+ and IR- were evaluated, as were correlations between mitochondrial respiration markers and biochemical measurements.

RESULTS

IR+ and IR- youth were similar on age, sex, and race/ethnicity. Mean age was 16.5 and 15.6 years in IR+ and IR-, respectively. The IR+ group had significantly higher mean BMI and metabolic analytes (fasting glucose, insulin, cholesterol, triglycerides, and venous lactate and pyruvate) compared with the IR-. Mitochondrial respiration markers were, on average, lower in the IR+ compared with IR-, including basal respiration (417.5 vs. 597.5 pmol, P = 0.074), ATP production (11 513 vs. 15 202 pmol, P = 0.078), proton leak (584.6 vs. 790.0 pmol, P = 0.033), maximal respiration (1815 vs. 2399 pmol, P = 0.025), and spare respiration capacity (1162 vs. 2017 pmol, P = 0.032). Nonmitochondrial respiration did not differ by IR status. The results did not change when adjusted for age.

CONCLUSION

HIV-infected youth with IR have lower mitochondrial respiration markers when compared to youth without IR. Disordered mitochondrial respiration may be a potential mechanism for IR in this population.

Antiretroviral therapy-induced mitochondrial toxicity: potential mechanisms beyond polymerase-γ inhibition

We hypothesized that competition between nucleotide reverse-transcriptase inhibitor triphosphate and endogenous deoxyribonucleotide triphosphate (dNTP) may lead to depletion of dNTP pools and mitochondrial dysfunction independent of polymerase-γ (pol-γ) inhibition. We collected peripheral blood mononuclear cells from 75 adults (25 cases: HIV-infected patients with mitochondrial toxicity, 25 HIV-infected positive controls, and 25 HIV-negative controls). We observed statistically significant individual and group differences in ribonucleotide (RN) and deoxyribonucleotide (dRN) pools. The median values for the RN pools were 10,062 (interquartile range (IQR): 7,090-12,590), 4,360 (IQR: 3,058-6,838), and 2,968 (IQR: 2,538-4,436) pmol/10(6) cells for negative controls, positive controls, and cases, respectively. Cases had significantly higher absolute mitochondrial DNA copy number as compared with negative controls (P < 0.05). Moreover, cases had significantly higher expression levels of pol-γ, nucleotide transporters, cellular kinases, and adenosine triphosphate (ATP)-binding cassette (ABC) proteins as compared with controls. Antiretroviral therapy (ART) perturbs RN and dRN pools. Depletion of RN and dRN pools may be associated with ART-induced mitochondrial toxicity independent of pol-γ inhibition.

Alterations in the levels of vesicular trafficking proteins involved in HIV replication in the brains and CSF of patients with HIV-associated neurocognitive disorders

Human immunodeficiency virus (HIV) associated neurocognitive disorders (HAND) remain prevalent despite improved antiretroviral therapies. A HAND-specific biomarker indicative of neuropsychological impairment (NPI) would give insight into disease progression and aid clinicians in designing therapy. Endosomal sorting complex required for transport (ESCRT) proteins such as tumor susceptibility gene (TSG)-101, vacuolar protein sorting (VPS)-4 and LIP-5 are important for HIV replication and recently antiviral interferon stimulated gene (ISG)-15 was proposed as a biomarker for CNS injury. Here, we analyzed a well-characterized cohort of HIV+ cerebral spinal fluid (CSF) and postmortem brain specimens for multiple vesicular trafficking proteins and a related innate immune protein, ISG-15, TSG-101, VPS-4 and LIP-5. All protein levels trended higher with increased NPI and neuropathology. ISG-15 CSF levels were increased in HIV encephalitis (HIVE) compared to normal cases, and three quarters of HIVE samples had above average CSF ISG-15 levels. VPS-4 CSF levels were increased in NPI/NPI-O compared to normal patients. VPS-4 CSF levels in HIV-associated dementia were equivalent to that of normal patients. LIP-5 CSF levels positively correlate with ISG-15 levels, and higher than average ISG-15 levels indicate elevated viral load. Immunoblot and immunohistochemical analyses show increased expression of ISG-15, VPS-4 and LIP-5 in neuronal cell bodies and astroglial cells. ESCRT protein CSF levels analyzed in conjunction with viral load may be indicative of NPI stage, and may aid in the diagnosis and design of therapies for HIV patients. Further studies on the ESCRT protein expression during HIV infection may lead to a promising biomarker for predicting progression of NPI.