Impact of the immune profiles of hypertensive patients with and without obesity on COVID-19 severity.

BACKGROUND: Comorbidities such as obesity, hypertension, and diabetes are associated with COVID-19 development and severity, probably due to immune dysregulation; however, the mechanisms underlying these associations are not clear. The immune signatures of hypertensive patients with obesity with COVID-19 may provide new insight into the mechanisms of immune dysregulation and progression to severe disease in these patients. METHODS: Hypertensive patients were selected prospectively from a multicenter registry of adults hospitalized with COVID-19 and stratified according to obesity (BMI ≥ 30 kg/m²). Clinical data including baseline characteristics, complications, treatment, and 46 immune markers were compared between groups. Logistic regression was performed to identify variables associated with the risk of COVID-19 progression in each group. RESULTS: The sample comprised 213 patients (89 with and 124 without obesity). The clinical profiles of patients with and without obesity differed, suggesting potential interactions with COVID-19 severity. Relative to patients without obesity, patients with obesity were younger and fewer had cardiac disease and myocardial injury. Patients with obesity had higher EGF, GCSF, GMCSF, interleukin (IL)-1ra, IL-5, IL-7, IL-8, IL-15, IL-1ß, MCP 1, and VEGF levels, total lymphocyte counts, and CD8+ CD38+ mean fluorescence intensity (MFI), and lower NK-NKG2A MFI and percentage of CD8+ CD38+ T cells. Significant correlations between cytokine and immune cell expression were observed in both groups. Five variables best predicted progression to severe COVID-19 in patients with obesity: diabetes, the EGF, IL-10, and IL-13 levels, and the percentage of CD8+ HLA-DR+ CD38+ cells. Three variables were predictive for patients without obesity: myocardial injury and the percentages of B lymphocytes and HLA-DR+ CD38+ cells. CONCLUSION: Our findings suggest that clinical and immune variables and obesity interact synergistically to increase the COVID-19 progression risk. The immune signatures of hypertensive patients with and without obesity severe COVID-19 highlight differences in immune dysregulation mechanisms, with potential therapeutic applications.

New Insights on the Mechanisms of Myocardial Injury in Hypertensive Patients With COVID-19.

PURPOSE: Myocardial injury is common in hypertensive patients with 2019 coronavirus disease (COVID-19). Immune dysregulation could be associated to cardiac injury in these patients, but the underlying mechanism has not been fully elucidated. METHODS: All patients were selected prospectively from a multicenter registry of adults hospitalized with confirmed COVID-19. Cases had hypertension and myocardial injury, defined by troponin levels above the 99th percentile upper reference limit, and controls were hypertensive patients with no myocardial injury. Biomarkers and immune cell subsets were quantified and compared between the two groups. A multiple logistic regression model was used to analyze the associations of clinical and immune variables with myocardial injury. RESULTS: The sample comprised 193 patients divided into two groups: 47 cases and 146 controls. Relative to controls, cases had lower total lymphocyte count, percentage of T lymphocytes, CD8+CD38+ mean fluorescence intensity (MFI), and percentage of CD8+ human leukocyte antigen DR isotope (HLA-DR)+ CD38-cells and higher percentage of natural killer lymphocytes, natural killer group 2A (NKG2A)+ MFI, percentage of CD8+CD38+cells, CD8+HLA-DR+MFI, CD8+NKG2A+MFI, and percentage of CD8+HLA-DR-CD38+cells. On multivariate regression, the CD8+HLA-DR+MFI, CD8+CD38+MFI, and total lymphocyte count were associated significantly with myocardial injury. CONCLUSION: Our findings suggest that lymphopenia, CD8+CD38+MFI, and CD8+HLA-DR+MFI are immune biomarkers of myocardial injury in hypertensive patients with COVID-19. The immune signature described here may aid in understanding the mechanisms underlying myocardial injury in these patients. The study data might open a new window for improvement in the treatment of hypertensive patients with COVID-19 and myocardial injury.

Type 2 diabetes mellitus alters cardiac mitochondrial content and function in a non-obese mice model.

Type 2 diabetes mellitus (T2DM) is associated with an increase of premature appearance of several disorders such as cardiac complications. Thus, we test the hypothesis that a combination of a high fat diet (HFD) and low doses of streptozotocin (STZ) recapitulate a suitable mice model of T2DM to study the cardiac mitochondrial disturbances induced by this disease. Animals were divided in 2 groups: the T2DM group was given a HFD and injected with 2 low doses of STZ, while the CNTRL group was given a standard chow and a buffer solution. The combination of HFD and STZ recapitulate the T2DM metabolic profile showing higher blood glucose levels in T2DM mice when compared to CNTRL, and also, insulin resistance. The kidney structure/function was preserved. Regarding cardiac mitochondrial function, in all phosphorylative states, the cardiac mitochondria from T2DM mice presented reduced oxygen fluxes when compared to CNTRL mice. Also, mitochondria from T2DM mice showed decreased citrate synthase activity and lower protein content of mitochondrial complexes. Our results show that in this non-obese T2DM model, which recapitulates the classical metabolic alterations, mitochondrial function is impaired and provides a useful model to deepen study the mechanisms underlying these alterations.

NKG2A Expression among CD8 Cells Is Associated with COVID-19 Progression in Hypertensive Patients: Insights from the BRACE CORONA Randomized Trial.

Cardiovascular comorbidities and immune-response dysregulation are associated with COVID-19 severity. We aimed to explore the key immune cell profile and understand its association with disease progression in 156 patients with hypertension that were hospitalized due to COVID-19. The primary outcome was progression to severe disease. The probability of progression to severe disease was estimated using a logistic regression model that included clinical variables and immune cell subsets associated with the primary outcome. Obesity; diabetes; oxygen saturation; lung involvement on computed tomography (CT) examination; the C-reactive protein concentration; total lymphocyte count; proportions of CD4+ and CD8+ T cells; CD4/CD8 ratio; CD8+ HLA-DR MFI; and CD8+ NKG2A MFI on admission were all associated with progression to severe COVID-19. This study demonstrated that increased CD8+ NKG2A MFI at hospital admission, in combination with some clinical variables, is associated with a high risk of COVID-19 progression in hypertensive patients. These findings reinforce the hypothesis of the functional exhaustion of T cells with the increased expression of NKG2A in patients with severe COVID-19, elucidating how severe acute respiratory syndrome coronavirus 2 infection may break down the innate antiviral immune response at an early stage of the disease, with future potential therapeutic implications.

IL-10 and IL-12 (P70) Levels Predict the Risk of Covid-19 Progression in Hypertensive Patients: Insights From the BRACE-CORONA Trial.

Background: Cardiovascular comorbidities such as hypertension and inflammatory response dysregulation are associated with worse COVID-19 prognoses. Different cytokines have been proposed to play vital pathophysiological roles in COVID-19 progression, but appropriate prognostic biomarkers remain lacking. We hypothesized that the combination of immunological and clinical variables at admission could predict the clinical progression of COVID-19 in hypertensive patients. Methods: The levels of biomarkers, including C-reactive protein, lymphocytes, monocytes, and a panel of 29 cytokines, were measured in blood samples from 167 hypertensive patients included in the BRACE-CORONA trial. The primary outcome was the highest score during hospitalization on the modified WHO Ordinal Scale for Clinical Improvement. The probability of progression to severe disease was estimated using a logistic regression model that included clinical variables and biomarkers associated significantly with the primary outcome. Results: During hospitalization, 13 (7.8%) patients showed progression to more severe forms of COVID-19, including three deaths. Obesity, diabetes, oxygen saturation, lung involvement on computed tomography examination, the C-reactive protein level, levels of 15 cytokines, and lymphopenia on admission were associated with progression to severe COVID-19. Elevated levels of interleukin-10 and interleukin-12 (p70) combined with two or three of the abovementioned clinical comorbidities were associated strongly with progression to severe COVID-19. The risk of progression to severe disease reached 97.5% in the presence of the five variables included in our model. Conclusions: This study demonstrated that interleukin-10 and interleukin-12 (p70) levels, in combination with clinical variables, at hospital admission are key biomarkers associated with an increased risk of disease progression in hypertensive patients with COVID-19.