Losartan to reduce inflammation and fibrosis endpoints in HIV disease

Corneal fibrosis: From in vitro models to current and upcoming drug and gene medicines

Fibrotic diseases are characterised by myofibroblast differentiation, uncontrolled pathological extracellular matrix accumulation, tissue contraction, scar formation and, ultimately tissue / organ dysfunction. The cornea, the transparent tissue located on the anterior chamber of the eye, is extremely susceptible to fibrotic diseases, which cause loss of corneal transparency and are often associated with blindness. Although topical corticosteroids and antimetabolites are extensively used in the management of corneal fibrosis, they are associated with glaucoma, cataract formation, corneoscleral melting and infection, imposing the need of far more effective therapies. Herein, we summarise and discuss shortfalls and recent advances in in vitro models (e.g. transforming growth factor-β (TGF-β) / ascorbic acid / interleukin (IL) induced) and drug (e.g. TGF-β inhibitors, epigenetic modulators) and gene (e.g. gene editing, gene silencing) therapeutic strategies in the corneal fibrosis context. Emerging therapeutical agents (e.g. neutralising antibodies, ligand traps, receptor kinase inhibitors, antisense oligonucleotides) that have shown promise in clinical setting but have not yet assessed in corneal fibrosis context are also discussed.

Insights into elastic fiber fragmentation: Mechanisms and treatment of aortic aneurysm in Marfan syndrome

Marfan syndrome (MFS) is an autosomal dominant connective tissue disorder caused by mutations in fibrillin 1 (FBN1) gene. These mutations result in defects in the skeletal, ocular, and cardiovascular systems. Aortic aneurysm is the leading cause of premature mortality in untreated MFS patients. Elastic fiber fragmentation in the aortic vessel wall is a hallmark of MFS-associated aortic aneurysms. FBN1 mutations result in FBN1 fragments that also contribute to elastic fiber fragmentation. Although recent research has advanced our understanding of MFS, the contribution of elastic fiber fragmentation to the pathogenesis of aneurysm formation remains poorly understood. This review provides a comprehensive overview of the molecular mechanisms of elastic fiber fragmentation and its role in the pathogenesis of aortic aneurysm progression. Increased comprehension of elastic fragmentation has significant clinical implications for developing targeted interventions to block aneurysm progression, which would benefit not only individuals with Marfan syndrome but also other patients with aneurysms. Moreover, this review highlights an overlooked connection between inhibiting aneurysm and the restoration of elastic fibers in the vessel wall with various aneurysm inhibitors, including drugs and chemicals. Investigating the underlying molecular mechanisms could uncover innovative therapeutic strategies to inhibit elastin fragmentation and prevent the progression of aneurysms.

Pharmacological and Behavioral Interventions to Mitigate Premature Aging in Patients with HIV

PURPOSE OF REVIEW

We sought to review pharmacological and behavioral interventions that have been publicly presented, published, or are currently ongoing to prevent or mitigate the effect of premature HIV-associated comorbidities.

RECENT FINDINGS

Multiple studies have been conducted in hopes of finding an effective intervention. While the choice of antiretroviral regimen influences recovery of immune function, several drugs used as adjunct treatments have proven effective to mitigate premature aging. Additionally, few behavioral interventions have exhibited some efficacy. Statins, angiotensin-receptor blockers, and anti-hyperglycemic agents as well as optimal adherence, exercise, and intermittent fasting among others have had beneficial impact on markers of immune activation and levels of inflammatory biomarkers. However, several investigations had inconclusive outcomes so further studies with larger sample sizes are warranted.

An open label randomized controlled trial of atorvastatin versus aspirin in elite controllers and antiretroviral-treated people with HIV

BACKGROUND

Residual inflammation in people with HIV (PWH) despite suppression of HIV replication is associated with many comorbidities including cardiovascular disease. Targeting inflammation may decrease the risk of cardiovascular disease.

METHODS

An open label randomized study was conducted to evaluate the effect of nine months of 81 mg aspirin versus 40 mg atorvastatin in antiretroviral therapy (ART) treated PWH and elite controllers (EC), not on ART. Biomarkers associated with inflammation and virologic indices were measured and analyzed using nonparametric and linear mixed effect models.

RESULTS

Fifty-three participants were randomized and 44 were included in the final analysis. Median age was 54 years, 72% were male, 59% were Black. Median CD4 + count was 595 cells/μl in the aspirin and 717 cells/μl in the atorvastatin arm. After 9 months of treatment, plasma soluble (s) CD14 + was reduced in the aspirin group within both treated PWH and EC ( P  = 0.0229), yet only within treated PWH in the atorvastatin group ( P  = 0.0128). A 2.3% reduction from baseline in tissue factor levels was also observed in the aspirin arm, driven by the EC group. In the atorvastatin arm, there was a 4.3% reduction in interleukin-8 levels ( P  = 0.02) and a small decrease of activated CD4 + T cells ( P  < 0.001). No statistically significant differences were observed in the plasma HIV viral load and cell-associated (CA) HIV DNA and RNA.

CONCLUSIONS

Aspirin and atorvastatin could play a role in targeting HIV-associated inflammation. Elite controllers may warrant special consideration for anti-inflammatory strategies.

Pathogenesis and management of emphysema in people with HIV

INTRODUCTION

Since early in the HIV epidemic, emphysema has been identified among people with HIV (PWH) and has been associated with increased mortality. Smoking cessation is key to risk reduction. Health maintenance for PWH and emphysema should ensure appropriate vaccination and lung cancer screening. Treatment should adhere to inhaler guidelines for the general population, but inhaled corticosteroid (ICS) should be used with caution. Frontiers in treatment include targeted therapeutics. Major knowledge gaps exist in the epidemiology of and optimal care for PWH and emphysema, particularly in low and middle-income countries (LMIC).

AREAS COVERED

Topics addressed include risk factors, pathogenesis, current treatment and prevention strategies, and frontiers in research.

EXPERT OPINION

There are limited data on the epidemiology of emphysema in LMIC, where more than 90% of deaths from COPD occur and where the morbidity of HIV is most heavily concentrated. The population of PWH is aging, and age-related co-morbidities such as emphysema will only increase in salience. Over the next 5 years, the authors anticipate novel trials of targeted therapy for emphysema specific to PWH, and we anticipate a growing body of evidence to inform optimal clinical care for lung health among PWH in LMIC.

Trametinib-Induced Epidermal Thinning Accelerates a Mouse Model of Junctional Epidermolysis Bullosa

Junctional epidermolysis bullosa (JEB) patients experience skin and epithelial fragility due to a pathological deficiency in genes associated with epidermal adhesion. Disease severity ranges from post-natal lethality to localized skin involvement with persistent blistering followed by granulation tissue formation and atrophic scarring. We evaluated the potential of utilizing Trametinib, an MEK inhibitor previously shown to target fibrosis, with and without the documented EB-anti-fibrotic Losartan for reducing disease severity in a mouse model of JEB; Lamc2^jeb mice. We found that Trametinib treatment accelerated disease onset and decreased epidermal thickness, which was in large part ameliorated by Losartan treatment. Interestingly, a range of disease severity was observed in Trametinib-treated animals that tracked with epidermal thickness; those animals grouped with higher disease severity had thinner epidermis. To examine if the difference in severity was related to inflammation, we conducted immunohistochemistry for the immune cell markers CD3, CD4, CD8, and CD45 as well as the fibrotic marker αSMA in mouse ears. We used a positive pixel algorithm to analyze the resulting images and demonstrated that Trametinib caused a non-significant reduction in CD4 expression that inversely tracked with increased fibrotic severity. With the addition of Losartan to Trametinib, CD4 expression was similar to control. Together, these data suggest that Trametinib causes a reduction in both epidermal proliferation and immune cell infiltration/proliferation, with concurrent acceleration of skin fragility, while Losartan counteracts Trametinib's adverse effects in a mouse model of JEB.

Effect of sacubitril/valsartan and ACEI/ARB on glycaemia and the development of diabetes: a systematic review and meta-analysis of randomised controlled trials

BACKGROUND

Sacubitril/valsartan and angiotensin-converting enzyme inhibitor (ACEI)/angiotensin-receptor blocker (ARB) therapies were reported to affect glycaemic control and the development of diabetes mellitus (DM), but the findings are inconsistent. We examined the evidence for the effects of sacubitril/valsartan and ACEI/ARB in DM by conducting a meta-analysis.

METHODS

The Cochrane Central Register of Controlled Trials (The Cochrane Library), Embase, PubMed, and ClinicalTrials.gov were searched for data from randomised clinical trials (RCTs) that evaluated the efficacy of sacubitril/valsartan and ACEI/ARB in patients, as of May 25, 2022. Patients were grouped by their disease background at baseline. The main outcomes were the number of new-onset DM and hypoglycaemia, elevated glycaemia, inadequate DM control, diabetes treatment, and diabetic complications, from baseline to the end of the trials. The risk of bias was assessed using the revised Cochrane risk-of-bias tool for randomized trials (ROB 2). The quality of the evidence was evaluated according to the Recommendations for Assessment, Development, and Evaluation guidelines. The meta-analysis of the incidence of various outcomes was conducted using fixed or random effects models. The results are expressed as binary risk, 95% confidence interval (CI), and relative risk (RR). The Mantel-Haenszel method and Z test were used to determine the overall results and determine the significance of the RR.

RESULTS

This study included 31 RCTs and 86,809 subjects. Compared with placebo, sacubitril/valsartan treatment significantly reduced the risk of new-onset DM among all patients (RR = 0.78, 95% CI: 0.64-0.95), patients with heart failure (HF) (RR = 0.24, 95% CI: 0.12-0.48), HF with reduced ejection fraction (HFrEF) (RR = 0.24, 95% CI: 0.12-0.50), and HF with preserved ejection fraction (HFpEF) (RR = 0.54, 95% CI 0.34-0.85). In contrast, sacubitril/valsartan treatment significantly increased the risk of hypoglycaemia among all patients (RR = 1.91, 95% CI: 1.05-3.47), patients with not all-DM (defined as part of the study population having DM at baseline) (RR = 5.71, 95% CI: 2.02-16.21), and patients with HFpEF (RR = 7.06, 95% CI: 2.10-23.76). Compared with ACEI/ARB, sacubitril/valsartan treatment significantly increased the risk of hypoglycaemia among patients with HF (RR 1.85, 95% CI 1.12-3.06, p = 0.02) and HFpEF (RR 3.59, 95% CI 1.51-8.55, p = 0.004). Compared with placebo, ACEI/ARB treatment did significantly reduce the risk of new-onset DM among all patients (RR 0.85, 95% CI 0.77-0.93, p = 0.0007) and patients with not all-HF (defined as part of the study population having HF at baseline) (RR 0.87, 95% CI 0.82-0.93, p<0.0001) and HFpEF (RR 0.60, 95% CI 0.44-0.83, p = 0.002), diabetes complications among patients with non-HF (/not all-DM) (RR 0.87, 95% CI 0.76-0.99, p = 0.04), and subsequent diabetes treatment among patients with new-onset DM (RR 0.70, 95% CI 0.58-0.84, p = 0.0002) and significantly increased the risk of hypoglycaemia among patients with not all-DM (RR 2.06, 95% CI 1.172-3.61, p = 0.01).

CONCLUSIONS

The results of our study, especially in reducing glycaemia and new-onset DM, revealed that sacubitril/valsartan had a positive effect on the control of glycaemia and the development of DM. ACEI/ARB also had a beneficial effect but the effect was weaker than that of sacubitril/valsartan. The above effects varied across diseases but the evidence was strongest in patients with HF.

TRIAL REGISTRATION

CRD42022336311.

The immunomodulatory effects of antihypertensive therapy: A review

Hypertension remains the leading preventable risk factor for stroke and coronary artery disease, significantly contributing to all-cause global mortality and predisposing patients to renal and heart failure, as well as peripheral vascular disease. Due to the widespread usage of antihypertensive drugs, global mean blood pressure has remained unchanged or even slightly decreased over the past four decades. However, considering the broad spectrum of mechanisms involved in the action of antihypertensive drugs and the prevalence of their target receptors on immune cells, possible immunomodulatory effects which may exert beneficial effects of lowering blood pressure but also potentially alter immune function should be considered. In this review, we attempt to assess the consequences to immune system function of administering the five most commonly prescribed groups of antihypertensive drugs and to explain the mechanisms behind those interactions. Finally, we show potential gaps in our understanding of the effects of antihypertensive drugs on patient health. With regard to the widespread use of these drugs in the adult population worldwide, the discussed results may be of vital importance to evidence-based decision-making in daily clinical practice.

Short Communication: A Pilot Study of the Effects of Losartan Versus Placebo on Pneumoproteins in HIV: A Secondary Analysis of a Randomized Double Blind Study

HIV is an independent risk factor for lung disease, including chronic obstructive pulmonary disease (COPD) and emphysema. Angiotensin receptor blockers may be beneficial in COPD and emphysema through pathways that have been implicated in HIV-related lung disease. We performed a randomized comparison of the effects of losartan versus placebo on the plasma concentrations of the pneumoproteins, surfactant protein D (SPD) and club cell secretory protein (CCSP), in people living with HIV (PLWH). A total of 108 PLWH were included (52 assigned to losartan and 56 assigned to placebo). We found no difference in the change from baseline in log₂ concentrations of CCSP or SPD over 1 year of follow-up. For SPD, we found a strong interaction by CD4+ counts, where those with CD4+ counts >350 cells/mm³ treated with losartan had more reduction (improvement) in SPD concentration than those treated with placebo (p value for interaction <.001). In conclusion, we did not find a beneficial effect of losartan on pneumoprotein concentrations in PLWH, but PLWH with higher CD4+ counts may have improvement in SPD when treated with losartan.

Mechanisms and primary prevention of atherosclerotic cardiovascular disease among people living with HIV

PURPOSE OF REVIEW

To highlight mechanisms of elevated risk of atherosclerotic cardiovascular disease (ASCVD) among people living with HIV (PLWH), discuss therapeutic strategies, and opportunities for primary prevention.

RECENT FINDINGS

HIV-associated ASCVD risk is likely multifactorial and due to HIV-specific factors and traditional risk factors even in the setting of treated and suppressed HIV disease. Although a growing body of evidence suggests that inflammation and immune activation are key drivers of atherogenesis, therapies designed to lower inflammation including colchicine and low-dose methotrexate have not improved secondary cardiovascular endpoints among PLWH. Statins continue to be the mainstay of management of hyperlipidemia in HIV, but the impact of newer lipid therapies including proprotein convertase subtilisin/kexin type 9 inhibitors on ASCVD risk among PLWH is under investigation. Aside from the factors mentioned above, healthcare disparities are particularly prominent among PLWH and thus likely contribute to increased ASCVD risk.

SUMMARY

Our understanding of mechanisms of elevated ASCVD risk in HIV continues to evolve, and the optimal treatment for CVD in HIV aside from targeting traditional risk factors remains unknown. Future studies including novel therapies to lower inflammation, control of risk factors, and implementation science are needed to ascertain optimal ways to treat and prevent ASCVD among PLWH.

Residual immune dysfunction under antiretroviral therapy

The usage of combination antiretroviral therapy in people with HIV (PWH) has incited profound improvement in morbidity and mortality. Yet, PWH may not experience full restoration of immune function which can manifest with non-AIDS comorbidities that frequently associate with residual inflammation and can imperil quality of life or longevity. In this review, we discuss the pathogenesis underlying chronic inflammation and residual immune dysfunction in PWH, as well as potential therapeutic interventions to ameliorate them and prevent incidence or progression of non-AIDS comorbidities. Current evidence advocates that early diagnosis and prompt initiation of therapy at high CD4 counts may represent the best available approach for an improved immune recovery in PWH.