Monocyte activation and gut barrier dysfunction in South African youth on antiretroviral therapy and their associations with endothelial dysfunction

Gut permeability is associated with lower insulin sensitivity in youth with perinatally acquired HIV

The relationships between alterations in the intestinal barrier, and bacterial translocation with the development of metabolic complications in youth with perinatally acquired HIV (YPHIV) have not been investigated. The PHACS Adolescent Master Protocol enrolled YPHIV across 15 U.S. sites, including Puerto Rico, from 2007 to 2009. For this analysis, we included YPHIV with HIV viral load 1000 c/ml or less, with at least one measurement of homeostatic assessment of insulin resistance (HOMA-IR) or nonhigh density lipoprotein (non-HDLc) between baseline and year 3 and plasma levels of intestinal fatty-acid binding protein (I-FABP), lipopolysaccharide-binding protein (LBP), and zonulin levels at baseline. We fit linear regression models using generalized estimating equations to assess the association of baseline log 10 gut markers with log 10 HOMA-IR and non-HDLc at all timepoints. HOMA-IR or non-HDLc was measured in 237, 189, and 170 PHIV at baseline, Yr2, and Yr3, respectively. At baseline, median age (Q1, Q3) was 12 years (10, 14), CD4 + cell count was 762 cells/μl (574, 984); 90% had HIV RNA less than 400 c/ml. For every 10-fold higher baseline I-FABP, HOMA-IR dropped 0.85-fold at baseline and Yr2. For a 10-fold higher baseline zonulin, there was a 1.35-fold increase in HOMA-IR at baseline, 1.23-fold increase in HOMA-IR at Yr2, and 1.20-fold increase in HOMA-IR at Yr3 in adjusted models. For a 10-fold higher baseline LBP, there was a 1.23-fold increase in HOMA-IR at baseline in the unadjusted model, but this was slightly attenuated in the adjusted model. Zonulin was associated with non-HDLc at baseline, but not for the other time points. Despite viral suppression, intestinal damage may influence downstream insulin sensitivity in YPHIV.

HIV Infection, Antiretroviral Drugs, and the Vascular Endothelium

Endothelial cell activation, injury, and dysfunction underlies the pathophysiology of vascular diseases and infections associated with vascular dysfunction, including human immunodeficiency virus (HIV) and acquired immunodeficiency syndrome. Despite viral suppression with combination antiretroviral therapy (ART), people living with HIV (PLWH) are prone to many comorbidities, including neurological and neuropsychiatric complications, cardiovascular and metabolic diseases, premature aging, and malignancies. HIV and viral proteins can directly contribute to the development of these comorbidities. However, with the continued high prevalence of these comorbidities despite viral suppression, it is likely that ART or some antiretroviral (ARVs) drugs contribute to the development and persistence of comorbid diseases in PLWH. These comorbid diseases often involve vascular activation, injury, and dysfunction. The purpose of this manuscript is to review the current literature on ARVs and the vascular endothelium in PLWH, animal models, and in vitro studies. I also summarize evidence of an association or lack thereof between ARV drugs or drug classes and the protection or injury/dysfunction of the vascular endothelium and vascular diseases.

Whole-protein enteral nutrition formula supplementation reduces Escherichia and improves intestinal barrier function in HIV-infected immunological nonresponders

People living with human immunodeficiency virus (PLWH) have persistent malnutrition, intestinal barrier dysfunction, and gut microbial imbalance. The interplay between gut microbiota and nutrients is involved in the immune reconstitution of PLWH. To evaluate the effects of whole-protein enteral nutrition formula supplementation on T-cell levels, intestinal barrier function, nutritional status, and gut microbiota composition in human immunodeficiency virus (HIV)-infected immunological nonresponders (INRs) who failed to normalize CD4+ T-cell counts, with a number <350 cells/µL, a pilot study was carried out in 13 HIV-infected INRs undergoing antiretroviral therapy who received a 3-month phase supplementation of 200 mL/200 kcal/45 g whole-protein enteral nutrition formula once daily. Our primary endpoint was increased CD4+ T-cell counts. Secondary outcome parameters were changes in intestinal barrier function, nutritional status, and gut microbiota composition. We showed that CD4+ T-cell counts of HIV-infected INRs increased significantly after the 3-month supplementation. Dietary supplementation for 3 months improved the intestinal barrier function and nutritional status of HIV-infected INRs. Furthermore, the enteral nutrition formula significantly decreased the relative abundance of Escherichia at the genus level and increased the alpha diversity of gut microbiota in HIV-infected INRs. The findings demonstrated that the whole-protein enteral nutrition formula aids in reducing Escherichia and improving intestinal barrier function in HIV-infected INRs. This study provides insight into the role of nutrients in the improvement of immune reconstitution in HIV-infected INRs. This study is registered in the Chinese Clinical Trial Registry (Document No. ChiCTR2000037839; http://www.chictr.org.cn/index.aspx).

Endothelial Peripheral Arterial Tonometry (Endo-PAT 2000) use in paediatric patients: a systematic review

OBJECTIVES

Endo Peripheral Artery Tonometry (EndoPAT-2000) is a non-invasive technology for measuring endothelial dysfunction (ED). The reactive hyperaemia index (RHI) is resulted and is low when ED is present. We aim to synthesise the literature on paediatric ED that used Endo-PAT analysis.

DESIGN

A comprehensive systematic review was conducted from January 2015 to March 2021. The databases included Cochrane, MEDLINE EBSCO, EMBASE (Ovid), PUBMED and CINAHL EBSCO. Exclusion criteria were: (1) If a study used a different device, for example, (2) If the study had no results. Inclusion criteria were: (1) Published in the English, (2) more than 50% of study subjects were in the paediatric age range, (3) data relevant to paediatric age range children could be extrapolated from all data, where not all study subjects were children.

RESULTS

Following the removal of duplicates, 156 articles were initially identified. Following exclusion, 50 articles were included for review. We have subdivided these papers into different systems for ease of reference and have reported our findings in six tables: patients with type 1/2 diabetes, obesity, cardiovascular, respiratory, psychiatric conditions and miscellaneous diseases. For each, the study design, population, control group (if available), RHI results and conclusions were reported.

CONCLUSIONS

A number of papers using Endo-PAT for children with various chronic diseases have evidence of ED. However, in many cases, there has only been a single cohort study using Endo-PAT. Further studies are required to validate these findings and to help characterise the cardiovascular risk profile of children with chronic disease. Further studies are also required that will characterise more completely the cardiovascular risk profile of these children.Consensus on other vascular risk markers that could be included in future studies is ideal and if accomplished, this would facilitate meta-analyses of studies of relatively rare conditions.

Coordination of inflammatory responses in children with perinatally-acquired HIV infection

OBJECTIVE

We investigated dynamics of inflammatory biomarkers in children with perinatally-acquired HIV (PHIV) who started antiretrovirals at age <3 years and achieved sustained virologic control (HIV plasma RNA<400 copies/mL).

DESIGN

This was a retrospective analysis of inflammatory biomarkers in children enrolled in a randomized trial of early (<3 years of age) PI-based versus NNRTI-based regimens (P1060), who achieved sustained virologic control and participated in a neurodevelopmental follow-up study (P1104 s) between ages 5-11 years.

METHODS

We measured 20 inflammatory biomarkers using ELISA or chemiluminescence at onset of sustained virologic control (Tc) and at P1104 s entry (Te).

RESULTS

The 213 participants had median ages of 1.2, 1.9, and 7.0 years at antiretroviral initiation, Tc, and Te, respectively, with 138 on PI-based and 74 on NNRTI-based regimens at Tc. Eighteen markers decreased and two increased from Tc to Te (Te-Tc). Biomarker subsets, particularly cytokines, the chemokine IP-10, and adhesion molecules sICAM-1 and sVCAM-1, correlated at Tc, Te, and Te-Tc. At Tc, higher biomarker levels were associated with younger age, female sex, HIV plasma RNA ≥750,000 copies/mL, lower nadir CD4+%, lower nadir weight z-scores, and NNRTI-based treatment. Greater Te-Tc biomarker declines were associated with younger age, male sex, higher Tc biomarker levels, lower nadir CD4+%, and NNRTI-based treatment. Duration of controlled viremia and nadir height Z-scores showed mixed associations.

CONCLUSIONS

Biomarker expression showed substantial coordination. Most markers decreased after virologic control. Demographic and clinical variables associated with biomarker patterns were identified. Mechanistic studies of these biomarker patterns are needed to inform interventions to control inflammation.

Association between CD4+ T cell counts and gut microbiota and serum cytokines levels in HIV-infected immunological non-responders

Background

CD4⁺ T cell counts in certain human immunodeficiency virus (HIV)-infected patients called immunological non-responders (INRs) could not return to a normal level even with sustained antiretroviral therapy (ART) because of persistent immune activation, which is associated with pro-inflammatory cytokines production and an altered intestinal microbiome profile. Changes in gut bacterial composition have been linked to low CD4⁺ T cell counts in HIV-infected individuals. However, the association between CD4⁺ T cell counts and gut microbiota community composition and cytokines levels in INRs (CD4⁺ T cell counts < 500 cells/μL) from Yunnan Province, China, has not been previously investigated.

Methods

To address this issue, we carried out a cross-sectional study of 34 HIV-infected INRs. The patients were divided into CD4 count > 200 cells/μL group and CD4 count < 200 cells/μL group. The gut microbiota composition of each subject was analyzed by 16S rRNA gene sequencing. We also compared CD8⁺ T cell counts, pro-inflammatory cytokines levels, and nutritional status between the two groups.

Results

Compared to INRs with CD4 count > 200 cells/μL, those with CD4 count < 200 cells/μL had a lower CD4/CD8 ratio, lower nutritional status and higher serum levels of tumor necrosis factor (TNF)-α, interferon-γ-inducible protein (IP)-10 and interleukin (IL)-1α. Ruminococcaceae was less abundant in the CD4 count < 200 cells/μL group than in the CD4 count > 200 cells/μL group, and difference in alpha diversity was observed between the two groups. Moreover, CD4⁺ T cell counts were negatively associated with TNF-α and IL-1α levels and positively associated with the relative abundance of Ruminococcaceae.

Conclusions

Our study demonstrated that lower CD4⁺ T cell counts in INRs are associated with a reduced abundance of Ruminococcaceae in the gut and elevated serum pro-inflammatory cytokines levels. Thus, interventions targeting gut microbiota to increase CD4⁺ T cell counts are a potential strategy for promoting immune reconstitution in HIV-infected INRs.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12879-021-06491-z.

The association between neutrophil to lymphocyte ratio and endothelial dysfunction in people living with HIV on stable antiretroviral therapy

BACKGROUND

Residual inflammation is thought to promote endothelial dysfunction and cardiovascular disease risk among people living with HIV (PLWH) receiving antiretroviral therapy (ART). Whether the neutrophil-to-lymphocyte ratio (NLR), a putative marker of systemic inflammation, may be associated with endothelial dysfunction has not been investigated in PLWH on stable ART.

RESEARCH DESIGN AND METHODS

In this cross-sectional study, 210 PLWH (mean age 49 years, 79% males, 88/7/5% Caucasians/Africans/Hispanics) on long-term ART (median ART duration 8 years) were enrolled among those who were afferent to an Infectious Diseases outpatient clinic. The association between NLR and brachial flow-mediated dilation (bFMD) was analysed.

RESULTS

A curvilinear association was observed between logarithmic-NLR and logarithmic-bFMD (R square = 0.034, p = 0.027), with logarithmic-bFMD decreasing significantly with increasing logarithmic-NLR only in PLWH with high NLR (≥1.47, median NLR) (r = -0.369, p < 0.001). However, NLR had a poor accuracy in the prediction of low bFMD (≤4.55, median bFMD) in PLWH with high NLR (55% sensitivity, 80% specificity, Youden index 0.35 for NLR 2.20).

CONCLUSIONS

Although there is an inverse association between NLR and bFMD among long-term ART-treated PLWH with high NLR, NLR has a low discriminatory ability toward endothelial dysfunction in this category of patients.