Monocyte subtype counts are associated with 10-year cardiovascular disease risk as determined by the Framingham Risk Score among subjects of the LIFE-Adult study

Circulating Monocytes Are Predictive and Responsive in Moderate-to-Severe Plaque Psoriasis Subjects Treated with Apremilast

Monocytes play a critical role in the inflammation associated with psoriasis, and their abnormalities have been reported as biomarkers of cardiovascular event risk, a psoriasis comorbidity. Monocytic cells in chronic inflammatory disorders express elevated levels of cAMP phosphodiesterase. Restoring cAMP levels using the oral cAMP phosphodiesterase-4 inhibitor, apremilast, improves clinical outcomes for a subset of patients with psoriasis. We asked whether aberrant monocyte subsets or transcriptomic pathways can function as biomarkers of psoriasis endotypes that can predict enhanced clinical responses to cAMP phosphodiesterase inhibition. A 16-week open-label study of 22 patients with monocyte flow cytometric and transcriptomic analysis was performed. Subjects with elevated hyperadhesive monocyte doublets at baseline were more likely to be responders to apremilast (P < .0001); 82% of subjects with elevated hyperadhesive monocyte doublets achieved 50% reduction in PASI compared with 46% in those without elevated doublets. We observed a significant reduction in hyperadhesive monocyte-containing doublets and monocyte-platelet aggregates, suggesting an effect of apremilast on the adhesiveness of blood monocytes during chronic inflammation. Monocyte differentially expressed gene transcripts predictive of clinical response uncovered pharmacoendotypes with distinct patterns of nucleotide metabolism, energetics, and differentiation. Further study to understand the basis of drug responsiveness and to develop an apremilast psoriasis treatment algorithm using monocyte-refined gene expression is required to validate and become practical in clinical use, offering patients a test that personalizes their likelihood of clinical response.

Association of Monocyte-to-HDL Cholesterol Ratio with Endothelial Dysfunction in Patients with Type 2 Diabetes

Aims

To explore the relationship between monocyte-to-HDL cholesterol ratio (MHR) and endothelial function in patients with type 2 diabetes (T2DM).

Methods

243 patients diagnosed with T2DM were enrolled in this cross-sectional study. Patients were divided into two groups by flow-mediated dilation (FMD) quintile as nonendothelial dysfunction (FMD ≥ 6.4%) and endothelial dysfunction (FMD < 6.4%). The relationship between MHR and FMD was analyzed using Spearman's correlation, partial correlation, and multiple logistic regression analysis. ROC curve was fitted to evaluate the ability of MHR to predict endothelial dysfunction.

Results

Endothelial dysfunction was present in 193 (79%) patients. Patients with endothelial dysfunction had higher MHR (p < 0.05) than those without endothelial dysfunction. Furthermore, MHR had a significantly positive correlation with endothelial dysfunction (r = 0.17, p < 0.05), and the positive association persisted even after controlling for confounding factors (r = 0.14, p < 0.05). Logistic regression showed that MHR was an independent contributor for endothelial dysfunction (OR: 1.35 (1.08, 1.70), p < 0.05) and the risk of endothelial dysfunction increases by 61% with each standard deviation increase in MHR (OR: 1.61 (1.12, 2.30), p < 0.05) (model 1). After adjusting for sex, age, BMI, disease course, hypertension, smoking, and drinking (model 2) as well as HbA1c, HOMA-IR, C-reactive protein, and TG (model 3), similar results were obtained. In ROC analysis, the area of under the ROC curve (AUC) for MHR was 0.60 (95% CI 0.52-0.69, p < 0.05).

Conclusion

MHR was independently associated with endothelial dysfunction in T2DM patients. It could be a new biomarker for vascular endothelial function assessment.

CROI 2023: Neuropsychiatric Complications in People With HIV

The 2023 Conference on Retroviruses and Opportunistic Infections (CROI) featured new and impactful findings about neuropsychiatric complications in people with HIV and other infections. Reports included new evidence of (a) the importance of myeloid cells in the pathogenesis of HIV disease in the central nervous system, including as an HIV reservoir; (b) eukaryotic and prokaryotic viruses in cerebrospinal fluid during suppressive antiretroviral therapy; (c) the influence of sex on pathogenesis, including in novel neuropsychiatric biotypes identified by machine learning and other methods;(d) premature aging in people with HIV, including the brain-age gap observed on magnetic resonance imaging; (e) cellular and soluble biomarkers of neuropsychiatric complications in people with HIV; and (f) the neurotoxicity of certain antiretroviral drugs. This review summarizes these and other new findings and highlights new research directions for the neuro-HIV field.

A high-sucrose diet exacerbates the left ventricular phenotype in a high fat-fed streptozotocin rat model of diabetic cardiomyopathy

Left ventricular (LV) dysfunction is an early, clinically detectable sign of cardiomyopathy in type 2 diabetes mellitus (T2DM) that precedes the development of symptomatic heart failure. Preclinical models of diabetic cardiomyopathy are essential to develop therapies that may prevent or delay the progression of heart failure. This study examined the molecular, structural, and functional cardiac phenotype of two rat models of T2DM induced by a high-fat diet (HFD) with a moderate- or high-sucrose content (containing 88.9 or 346 g/kg sucrose, respectively), plus administration of low-dose streptozotocin (STZ). At 8 wk of age, male Sprague-Dawley rats commenced a moderate- or high-sucrose HFD. Two weeks later, rats received low-dose STZ (35 mg/kg ip for 2 days) and remained on their respective diets. LV function was assessed by echocardiography 1 wk before end point. At 22 wk of age, blood and tissues were collected postmortem. Relative to chow-fed sham rats, diabetic rats on a moderate- or high-sucrose HFD displayed cardiac reactive oxygen species dysregulation, perivascular fibrosis, and impaired LV diastolic function. The diabetes-induced impact on LV adverse remodeling and diastolic dysfunction was more apparent when a high-sucrose HFD was superimposed on STZ. In conclusion, a high-sucrose HFD in combination with low-dose STZ produced a cardiac phenotype that more closely resembled T2DM-induced cardiomyopathy than STZ diabetic rats subjected to a moderate-sucrose HFD.NEW & NOTEWORTHY Left ventricular dysfunction and adverse remodeling were more pronounced in diabetic rats that received low-dose streptozotocin (STZ) and a high-sucrose high-fat diet (HFD) compared with those on a moderate-sucrose HFD in combination with STZ. Our findings highlight the importance of sucrose content in diet composition, particularly in preclinical studies of diabetic cardiomyopathy, and demonstrate that low-dose STZ combined with a high-sucrose HFD is an appropriate rodent model of cardiomyopathy in type 2 diabetes.

Monocytes presenting a pro-inflammatory profile persist in patients submitted to a long-term pharmacological treatment after acute myocardial infarction

Introduction: Although it is broadly known that monocyte recruitment is involved in atherosclerosis development and that, in accordance with the microenvironment, these cells can be modulated into three well-known subpopulations: Classical (CD14++CD16-), intermediate (CD14++CD16+), and non-classical (CD14+CD16++), the effects of treatment with different pharmacological strategies (based on lipid-lowering and antiplatelets) after acute myocardial infarction upon the monocytes modulation and the role of the chemokine receptors CCR2, CCR5 and CX3CR1 in this context, are poorly understood. Methods: In this study, patients [n = 148, both men (n = 105, 71%) and women (n = 43, 29%)] submitted to treatment with a 2×2 factorial design, in which they received rosuvastatin 20 mg or simvastatin 40 mg plus ezetimibe 10 mg, as well as ticagrelor 90 mg or clopidogrel 75 mg were enrolled. Monocyte subsets were analyzed by flow cytometry at baseline (BL), and after one (1-M) and 6 months (6-M) of treatment. Results: Firstly, our results showed that, regardless of the treatment received, higher percentages of classical monocytes and lower of non-classical monocytes were found at the 6-M time point than BL values, whilst the percentage of intermediate monocytes was higher in all time points assessed than the other subsets. There were reductions in the CCR2 expression by non-classical and intermediate monocytes, without differences for the classical subtype. Concerning the CCR5 expression, there were reductions in the three monocyte subtypes, whereas the CX3CR1 expression increased both in intermediate and classical monocytes, without differences for non-classical monocytes. In relation to the treatment received, a higher percentage of intermediate monocytes at the 6-M time point than the values BL was observed in the group treated with simvastatin + ezetimibe + clopidogrel. No significant differences were found concerning non-classical, intermediate, and classical monocytes, for CCR2, CCR5, and CX3CR1 in the four treatment arms. Conclusion: Taken together, our results demonstrated that even under lipid-lowering and antiplatelet therapy for 6 months, the inflammatory phenotype of monocytes still persisted in the patients enrolled in this study.

Relationship Between Monocyte-to-Lymphocyte Ratio as Well as Other Leukocyte-Derived Ratios and Carotid Plaques in Patients with Coronary Heart Disease: A RCSCD-TCM Study

Purpose

This study explored the relationship between monocyte-to-lymphocyte ratio (MLR) as well as other leukocyte-derived ratios and carotid plaques in patients with coronary heart disease (CHD).

Patients and Methods

A total of 12,093 patients with CHD were selected as research participants. Leukocyte-derived ratios assessed in this study included neutrophil-to-lymphocyte ratio (NLR), derived NLR (dNLR), MLR, platelet-to-lymphocyte ratio (PLR), white blood cell-to-mean platelet volume ratio (WMR), lymphocyte×neutrophil/10⁴ ratio (MNM), systemic immune inflammation index (SII), and systemic inflammation response index (SIRI). Leukocyte-derived ratios were divided into four groups according to quarters. Logistic regression analysis was performed to evaluate the relationship between leukocyte-derived ratios and the incidence, number, and echo characteristics of carotid plaques in patients with CHD. Further analysis was performed after adjusting for confounding factors.

Results

Among the 12,093 participants, 71.7% had carotid plaques. After adjusting for confounding factors, MLR, NLR, dNLR, PLR, SII, SIRI, and WMR were found to be associated with carotid plaque formation. Among them, MLR had the strongest association with the incidence of carotid plaques (odd ratio[OR]:1.889; 95% confidence interval[CI]:1.406–2.539) and hyperechoic plaques (OR:2.024; 95% CI:1.481–2.767). When MLR was viewed as a categorical variable, the risk of carotid plaque formation in Q4 was 1.4 times higher than that in Q1. The relationship between MLR and carotid plaques in females (OR:2.250; 95% CI:1.458–3.473) was stronger than that in males (OR: 1.638; 95% CI:1.102–-2.436). The relationship between MLR and carotid plaques in patients younger than 65 years (OR:3.597; 95% CI:2.379–5.439) was stronger than that in those older than 65 years (OR:1.577; 95% CI:1.046–2.378).

Conclusion

Leukocyte-derived ratios were related to the incidence, number, and echo characteristics of carotid plaques. In particular, MLR, an inflammatory biomarker that encompasses innate and adaptive immunity, may be of great value in revealing the incidence and echo characteristics of plaques.

White blood cell count profile in patients with physical complaints without known causes

Objectives

The aim of this study was to search for routine blood test biomarkers in patients with physical symptoms but without a diagnosis after comprehensive routine screening diagnostic examinations.

Methods

A total of 228 adults aged < 65 years who presented with physical complaints without known causes after comprehensive screening diagnostic examinations and 228 age- and sex-matched healthy controls without physical complaints were enrolled. The blood cell count data at the first hospital visit were compared between these groups.

Results

Total white blood cell (p = 0.2143), red blood cell (p = 0.8954), and platelet (p = 0.7716) counts did not differ between the groups. The monocyte count (p = 0.0014) and resultant monocyte-to-lymphocyte ratio (p < 0.0001) were higher in the symptomatic group, while the other white blood cell subtypes did not differ significantly between the two groups. In the symptomatic group, patients with a monocyte-to-lymphocyte ratio > 0.25 were likely to have unexplained nonfocal physical symptoms (p < 0.0001). The characteristic findings included fatigability (p < 0.0001), prolonged slight fever (p = 0.0005), and widespread pain (p < 0.0001). The monocyte-to-lymphocyte ratio level was correlated with the proportion of patients with unexplained nonfocal symptoms.

Conclusion

The blood cell count profile was largely the same between healthy individuals and patients with unexplained physical symptoms. However, patients with unexplained nonfocal physical complaints were likely to show an elevated monocyte-to-lymphocyte ratio, typically > 0.25.

Circulating Monocyte Subsets and Transcatheter Aortic Valve Replacement

Transcatheter aortic valve replacement (TAVR), as an alternative to open heart surgery, has revolutionized the treatment of severe aortic valve stenosis (AVS), the most common valvular disorder in the elderly. AVS is now considered a form of atherosclerosis and, like the latter, partly of inflammatory origin. Patients with high-grade AVS have a highly disturbed blood flow associated with high levels of shear stress. The immediate reopening of the valve during TAVR leads to a sudden restoration of a normal blood flow hemodynamic. Despite its good prognosis for patients, TAVR remains associated with bleeding or thrombotic postprocedural complications, involving mechanisms that are still poorly understood. Many studies report the close link between blood coagulation and inflammation, termed thromboinflammation, including monocytes as a major actor. The TAVR procedure represents a unique opportunity to study the influence of shear stress on human monocytes, key mediators of inflammation and hemostasis processes. The purpose of this study was to conduct a review of the literature to provide a comprehensive overview of the impact of TAVR on monocyte phenotype and subset repartition and the association of these parameters with the clinical outcomes of patients with severe AVS who underwent TAVR.

Monocyte-to-Lymphocyte Ratio as a Predictor of Worse Long-Term Survival after Off-Pump Surgical Revascularization-Initial Report

Background and objective: Coronary artery disease is one of the leading causes of deaths nowadays and the trends in diagnosis and revascularization are still in plateau despite well-known factors. Simple whole blood count parameters may be used to measure inflammatory reactions that are involved in processes of atherosclerosis progression. The aim of our study was to analyse the association between simply available hematologic indices and long-term mortality following off-pump coronary artery bypass grafting (OPCAB). Material and Methods: The study group comprised 129 consecutive patients (16 females and 113 males, mean age 66 ± 6 years) who underwent surgical revascularization with off-pump technique between January 2014 and September 2019. The mean follow-up was 4.7 +/−1.9 years. A receiver operating characteristics curve was applied to estimate demographical and perioperative parameters including MLR for mortality. Results: Cox regression analysis revealed chronic pulmonary obstructive disease (HR = 2.86, 95%CI 1.05–7.78), MLR (HR = 3.81, 95%CI 1.45–10.06) and right coronary artery blood flow (HR = 1.06, 95%CI 1.00–1.10) as significant factors predicting increased mortality risk. In the presented model, the MLR > 1.44 on 1st postoperative day was a significant predictor of late mortality after the OPCAB procedure (HR = 3.82, 95%CI 1.45–10.06). Conclusions: Pronounced inflammatory reaction after off-pump surgery measured by MLR > 1.44 can be regarded as a worse long-term prognostic factor.

Metabolic regulation of macrophage proliferation and function in atherosclerosis

PURPOSE OF REVIEW

Macrophage accumulation within atherosclerotic plaque is a primary driver of disease progression. However, recent advances in both phenotypic and functional heterogeneity of these cells have allowed for improved insight into potential regulation of macrophage function within lesions. In this review, we will discuss recent insights on macrophage heterogeneity, lipid processing, metabolism, and proliferation in atherosclerosis. Furthermore, we will identify outstanding questions in the field that are pertinent to future studies.

RECENT FINDINGS

With the recent development of single-cell RNA sequencing, several studies have highlighted the diverse macrophage populations within plaques, including pro-inflammatory, anti-inflammatory, lipid loaded and tissue resident macrophages. Furthermore, new data has suggested that differential activation of metabolic pathways, including glycolysis and fatty acid oxidation, may play a key role in determining function. Recent works have highlighted that different populations retain varying capacity to undergo proliferation; regulating the proliferation pathway may be highly effective in reducing plaque in advanced lesions.

SUMMARY

Macrophage populations within atherosclerosis are highly heterogeneous; differences in cytokine production, lipid handling, metabolism, and proliferation are seen between subpopulations. Understanding the basic cellular mechanisms that drive this heterogeneity will allow for the development of highly specific disease modulating agents to combat atherosclerosis.