Delineating tesamorelin response pathways in HIV-associated NAFLD using a targeted proteomic and transcriptomic approach.

NAFLD is a leading comorbidity in HIV with an exaggerated course compared to the general population. Tesamorelin has been demonstrated to reduce liver fat and prevent fibrosis progression in HIV-associated NAFLD. We further showed that tesamorelin downregulated hepatic gene sets involved in inflammation, tissue repair, and cell division. Nonetheless, effects of tesamorelin on individual plasma proteins pertaining to these pathways are not known. Leveraging our prior randomized-controlled trial and transcriptomic approach, we performed a focused assessment of 9 plasma proteins corresponding to top leading edge genes within differentially modulated gene sets. Tesamorelin led to significant reductions in vascular endothelial growth factor A (VEGFA, log2-fold change - 0.20 ± 0.35 vs. 0.05 ± 0.34, P = 0.02), transforming growth factor beta 1 (TGFB1, - 0.35 ± 0.56 vs. - 0.05 ± 0.43, P = 0.05), and macrophage colony stimulating factor 1 (CSF1, - 0.17 ± 0.21 vs. 0.02 ± 0.20, P = 0.004) versus placebo. Among tesamorelin-treated participants, reductions in plasma VEGFA (r = 0.62, P = 0.006) and CSF1 (r = 0.50, P = 0.04) correlated with a decline in NAFLD activity score. Decreases in TGFB1 (r = 0.61, P = 0.009) and CSF1 (r = 0.64, P = 0.006) were associated with reduced gene-level fibrosis score. Tesamorelin suppressed key angiogenic, fibrogenic, and pro-inflammatory mediators. CSF1, a regulator of monocyte recruitment and activation, may serve as an innovative therapeutic target for NAFLD in HIV. Clinical Trials Registry Number: NCT02196831.

Placental Vascular Abnormalities in Association With Prenatal and Long-Term Health Characteristics Among HIV-Exposed Uninfected Adolescents and Young Adults.

BACKGROUND: HIV-exposed uninfected (HEU) individuals are predisposed to adverse health outcomes, which in part may stem from the influence of an altered intrauterine milieu on fetal programming. The placenta serves as a readout for the effects of the maternal environment on the developing fetus and may itself contribute to the pathogenesis of disease. SETTING: US academic health system. METHODS: We leveraged a previously established registry-based cohort of HEU adolescents and young adults to identify 26 subjects for whom placental histopathology was available. We further obtained placental tissue from 29 HIV-unexposed pregnancies for comparison. We examined differences in placental histopathology between the groups and related villous vascularity in the HEU group to prenatal maternal characteristics and long-term health outcomes. RESULTS: Placentas from HEU pregnancies demonstrated a higher blood vessel count per villus as compared with controls (5.9 ± 1.0 vs. 5.4 ± 0.8; P = 0.05), which was independent of maternal prenatal age, race, body mass index, smoking status, hemoglobin, and gestational age. Furthermore, within the HEU group, lower CD4+ T-cell count during pregnancy was associated with greater placental vascularity (r = -0.44; P = 0.03). No significant relationships were observed between placental blood vessel count per villus and body mass index z-score or reactive airway disease among HEU individuals later in life. CONCLUSIONS: Placentas from HEU pregnancies demonstrated increased villous vascularity compared with HIV-unexposed controls in proportion to the severity of maternal immune dysfunction. Further studies are needed to examine intrauterine exposure to hypoxia as a potential mechanism of fetal programming in HIV.

Growth Hormone Releasing Hormone Reduces Circulating Markers of Immune Activation in Parallel with Effects on Hepatic Immune Pathways in Individuals with HIV-infection and Nonalcoholic Fatty Liver Disease.

BACKGROUND: The growth hormone (GH)/insulin-like growth factor-1 (IGF-1) axis modulates critical metabolic pathways; however, little is known regarding effects of augmenting pulsatile GH secretion on immune function in humans. This study used proteomics and gene set enrichment analysis to assess effects of a GH releasing hormone (GHRH) analog, tesamorelin, on circulating immune markers and liver tissue in people with human immunodeficiency virus (HIV) (PWH) and nonalcoholic fatty liver disease (NAFLD). METHODS: 92 biomarkers associated with immunity, chemotaxis, and metabolism were measured in plasma samples from 61 PWH with NAFLD who participated in a double-blind, randomized trial of tesamorelin versus placebo for 12 months. Gene set enrichment analysis was performed on serial liver biopsies targeted to immune pathways. RESULTS: Tesamorelin, compared to placebo, decreased interconnected proteins related to cytotoxic T-cell and monocyte activation. Circulating concentrations of 13 proteins were significantly decreased, and no proteins increased, by tesamorelin. These included 4 chemokines (CCL3, CCL4, CCL13 [MCP4], IL8 [CXCL8]), 2 cytokines (IL-10 and CSF-1), and 4 T-cell associated molecules (CD8A, CRTAM, GZMA, ADGRG1), as well as ARG1, Gal-9, and HGF. Network analysis indicated close interaction among the gene pathways responsible for these proteins, with imputational analyses suggesting down-regulation of a closely related cluster of immune pathways. Targeted transcriptomics using liver tissue confirmed a significant end-organ signal of down-regulated immune activation pathways. CONCLUSIONS: Long-term treatment with a GHRH analog reduced markers of T-cell and monocyte/macrophage activity, suggesting that augmentation of the GH axis may ameliorate immune activation in an HIV population with metabolic dysregulation, systemic and end organ inflammation. Clinical Trials Registration. NCT02196831.

Relationship of IGF-1 and IGF-Binding Proteins to Disease Severity and Glycemia in Nonalcoholic Fatty Liver Disease.

CONTEXT: Growth hormone (GH) and IGF-1 help regulate hepatic glucose and lipid metabolism, and reductions in these hormones may contribute to development of nonalcoholic fatty liver disease (NAFLD). OBJECTIVE: To assess relationships between hepatic expression of IGF1 and IGF-binding proteins (IGFBPs) and measures of glycemia and liver disease in adults with NAFLD. Secondarily to assess effects of GH-releasing hormone (GHRH) on circulating IGFBPs. DESIGN: Analysis of data from a randomized clinical trial of GHRH. SETTING: Two US academic medical centers. PARTICIPANTS: Participants were 61 men and women 18 to 70 years of age with HIV-infection, ≥5% hepatic fat fraction, including 39 with RNA-Seq data from liver biopsy. MAIN OUTCOME MEASURES: Hepatic steatosis, inflammation, and fibrosis by histopathology and measures of glucose homeostasis. RESULTS: Hepatic IGF1 mRNA was significantly lower in individuals with higher steatosis and NAFLD Activity Score (NAS) and was inversely related to glucose parameters, independent of circulating IGF-1. Among the IGFBPs, IGFBP2 and IGFBP4 were lower and IGFBP6 and IGFBP7 (also known as IGFBP-related protein 1) were higher with increasing steatosis. Hepatic IGFBP6 and IGFBP7 mRNA levels were positively associated with NAS. IGFBP7 mRNA increased with increasing fibrosis. Hepatic IGFBP1 mRNA was inversely associated with glycemia and insulin resistance, with opposite relationships present for IGFBP3 and IGFBP7. GHRH increased circulating IGFBP-1 and IGFBP-3, but decreased IGFBP-2 and IGFBP-6. CONCLUSIONS: These data demonstrate novel relationships of IGF-1 and IGFBPs with NAFLD severity and glucose control, with divergent roles seen for different IGFBPs. Moreover, the data provide new information on the complex effects of GHRH on IGFBPs.

Clinical Predictors of Liver Fibrosis Presence and Progression in Human Immunodeficiency Virus-Associated Nonalcoholic Fatty Liver Disease.

BACKGROUND: Nonalcoholic fatty liver disease (NAFLD) affects more than one-third of people living with human immunodeficiency virus (HIV). Nonetheless, its natural history is poorly understood, including which patients are most likely to have a progressive disease course. METHODS: We leveraged a randomized trial of the growth hormone-releasing hormone analogue tesamorelin to treat NAFLD in HIV. Sixty-one participants with HIV-associated NAFLD were randomized to tesamorelin or placebo for 12 months with serial biopsies. RESULTS: In all participants with baseline biopsies (n = 58), 43% had hepatic fibrosis. Individuals with fibrosis had higher NAFLD Activity Score (NAS) (mean ± standard deviation [SD], 3.6 ± 2.0 vs 2.0 ± 0.8; P < .0001) and visceral fat content (mean ± SD, 284 ± 91 cm2 vs 212 ± 95 cm2; P = .005), but no difference in hepatic fat or body mass index. Among placebo-treated participants with paired biopsies (n = 24), 38% had hepatic fibrosis progression over 12 months. For each 25 cm2 higher visceral fat at baseline, odds of fibrosis progression increased by 37% (odds ratio, 1.37 [95% confidence interval, 1.03-2.07]). There was no difference in baseline NAS between fibrosis progressors and nonprogressors, though NAS rose over time in the progressor group (mean ± SD, 1.1 ± 0.8 vs -0.5 ± 0.6; P < .0001). CONCLUSIONS: In this longitudinal study of HIV-associated NAFLD, high rates of hepatic fibrosis and progression were observed. Visceral adiposity was identified as a novel predictor of worsening fibrosis. In contrast, baseline histologic characteristics did not relate to fibrosis progression.

Effects of tesamorelin on hepatic transcriptomic signatures in HIV-associated NAFLD.

Nonalcoholic fatty liver disease (NAFLD) is a common comorbidity among people living with HIV that has a more aggressive course than NAFLD among the general population. In a recent randomized placebo-controlled trial, we demonstrated that the growth hormone-releasing hormone analog tesamorelin reduced liver fat and prevented fibrosis progression in HIV-associated NAFLD over 1 year. As such, tesamorelin is the first strategy that has shown to be effective against NAFLD among the population with HIV. The current study leveraged paired liver biopsy specimens from this trial to identify hepatic gene pathways that are differentially modulated by tesamorelin versus placebo. Using gene set enrichment analysis, we found that tesamorelin increased hepatic expression of hallmark gene sets involved in oxidative phosphorylation and decreased hepatic expression of gene sets contributing to inflammation, tissue repair, and cell division. Tesamorelin also reciprocally up- and downregulated curated gene sets associated with favorable and poor hepatocellular carcinoma prognosis, respectively. Notably, among tesamorelin-treated participants, these changes in hepatic expression correlated with improved fibrosis-related gene score. Our findings inform our knowledge of the biology of pulsatile growth hormone action and provide a mechanistic basis for the observed clinical effects of tesamorelin on the liver.

Association of In Utero HIV Exposure With Obesity and Reactive Airway Disease in HIV-Negative Adolescents and Young Adults.

BACKGROUND: HIV-negative individuals with in utero HIV exposure represent an emerging population, exceeding 18 million people worldwide. Long-term clinical outcomes among HIV-exposed uninfected (HEU) individuals into adolescence and young adulthood remain unknown. SETTING: US academic health system. METHODS: In this observational cohort study, we leveraged a patient data registry to identify 50 HEU adolescents and young adults. We also identified 141 HIV-unexposed controls that were matched to HEU subjects up to 3:1 on age of last encounter (±2 years), birthdate (±5 years), sex, race/ethnicity, and zip code. All subjects were born since January 1, 1990, with medical records available into adolescence and young adulthood. Primary outcomes were most recent body mass index (BMI) z-score and presence of reactive airway disease (RAD). Records were manually reviewed to extract health information. RESULTS: Fifty HEU adolescents and young adults (18 ± 3 years, 54% men) and 141 matched controls (19 ± 3 years, 54% men) were compared. HEU individuals had a higher BMI z-score (1.12 ± 1.08 vs. 0.73 ± 1.09, P = 0.03) and an increased prevalence of obesity (42% vs. 22%, P = 0.009) compared with controls. HEU subjects also had a higher prevalence of RAD vs. controls (40% vs. 23%, P = 0.03). These differences persisted on adjusting for demographic, socioeconomic, maternal, and birth-related factors. Maternal prenatal CD4 T-cell count was inversely associated with BMI z-score among HEU adolescents (r = -0.47, P = 0.01). CONCLUSIONS: HEU adolescents and young adults exhibited a heightened prevalence of obesity and RAD compared with HIV-unexposed controls. Additional studies are needed to optimize care for the expanding population of HEU individuals transitioning to adulthood.

Effects of tesamorelin on non-alcoholic fatty liver disease in HIV: a randomised, double-blind, multicentre trial.

BACKGROUND: Non-alcoholic fatty liver disease (NAFLD) is a substantial cause of comorbidity in people with HIV and there are no proven pharmacological treatments for the disease in this population. We assessed the effects of tesamorelin on liver fat and histology in people with HIV and NAFLD. METHODS: This randomised, double-blind, multicentre study with identical placebo as a comparator was done in a hospital and a medical research centre in the USA. People with HIV infection and a hepatic fat fraction (HFF) of 5% or more by proton magnetic resonance spectroscopy were eligible. Participants were randomly assigned (1:1) to receive either tesamorelin 2 mg once daily or placebo once daily for 12 months, followed by a 6-month open-label phase during which all participants received tesamorelin 2 mg daily. The randomisation list was prepared by the study statistician using a permuted block algorithm within each stratum with randomly varying block sizes. The primary endpoint was change in HFF between baseline and 12 months. The primary safety endpoint was glucose. Analysis was by intention to treat using all available data. This trial is registered with ClinicalTrials.gov, number NCT02196831. FINDINGS: 61 patients were enrolled between Aug 20, 2015, and Jan 16, 2019, of whom 30 received tesamorelin and 30 received placebo. Patients receiving tesamorelin had a greater reduction of HFF than did patients receiving placebo, with an absolute effect size of -4·1% (95% CI -7·6 to -0·7, p=0·018), corresponding to a -37% (95% CI -67 to -7, p=0·016) relative reduction from baseline. After 12 months, 35% of individuals receiving tesamorelin and 4% receiving placebo had a HFF of less than 5% (p=0·0069). Changes in fasting glucose and glycated haemoglobin were not different between groups at 12 months. Individuals in the tesamorelin group experienced more localised injection site complaints than those in the placebo group, though none were judged to be serious. INTERPRETATION: Tesamorelin might be beneficial in people with HIV and NAFLD. Further studies are needed to determine the long-term effects of tesamorelin on liver histology. FUNDING: National Institutes of Health and National Institute of Allergy and Infectious Diseases.

Age-Related Autonomous Aldosteronism.

BACKGROUND: Both aging and inappropriate secretion of aldosterone increase the risk for developing cardiovascular disease; however, the influence of aging on aldosterone secretion and physiology is not well understood. METHODS: The relationship between age and adrenal aldosterone synthase (CYP11B2) expression was evaluated in 127 normal adrenal glands from deceased kidney donors (age, 9 months to 68 years). Following immunohistochemistry, CYP11B2-expressing area and areas of abnormal foci of CYP11B2-expressing cells, called aldosterone-producing cell clusters, were analyzed. In a separate ancillary clinical study of 677 participants without primary aldosteronism, who were studied on both high and restricted sodium diets (age, 18-71 years), we used multivariable linear regression to assess the independent associations between age and renin-angiotensin-aldosterone system physiology. RESULTS: In adrenal tissue, the total CYP11B2-expressing area was negatively correlated with age (r=-0.431, P<0.0001), whereas the total aldosterone-producing cell cluster area was positively correlated with age (r=0.390, P<0.0001). The integrated ratio of aldosterone-producing cell cluster to CYP11B2-expressing area was most strongly and positively correlated with age (r=0.587, P<0.0001). When participants in the clinical study were maintained on a high sodium balance, renin activity progressively declined with older age, whereas serum and urinary aldosterone did not significantly decline. Correspondingly, the aldosterone-to-renin ratio was positively and independently associated with older age (adjusted ß=+5.54 ng/dL per ng/mL per hour per 10 years, P<0.001). In contrast, when participants were assessed under sodium-restricted conditions, physiological stimulation of aldosterone was blunted with older age (ß=-4.6 ng/dL per 10 years, P<0.0001). CONCLUSIONS: Aging is associated with a pattern of decreased normal zona glomerulosa CYP11B2 expression and increased aldosterone-producing cell cluster expression. This histopathologic finding parallels an age-related autonomous aldosteronism and abnormal aldosterone physiology that provides 1 potential explanation for age-related cardiovascular risk.