Association of vitamin D3, VDR gene polymorphisms, and LL-37 with a clinical form of Chagas Disease

Abstract INTRODUCTION: Chagas disease (CD) is an important public health problem in Brazil and worldwide. Aging and obesity are important matters in patients with CD, as is hypovitaminosis D3, which can decrease the quality of life of these patients. Immunomodulation mediated by vitamin D3, especially the production of antimicrobial peptides such as cathelicidin LL-37, might be related to the severity and symptoms of CD. This study aimed to determine the serum levels of vitamin D and LL-37 and VDR gene polymorphisms in patients with chronic CD. METHODS: This study included male patients with cardiac and indeterminate clinical forms of CD. Clinical, anthropometric, and blood parameters were obtained. Serum levels of 25(OH)D3 and LL-37 were determined by chemiluminescence and enzyme-linked immunosorbent assay respectively. Fok (rs731236), Bsm (rs1544410), Apa (rs7975232), and Taq (rs731236) polymorphisms of the VDR gene were investigated by PCR-RFLP. RESULTS: Sixty-four patients were included in the study: 18 of the cardiac form and 46 of the indeterminate form. No differences in age, ethnicity, BMI, arterial hypertension, diabetes mellitus, or dyslipidemias were observed between groups. However, the serum levels of 25(OH)D3, but not of LL-37, were lower in the cardiac form group. The association among polymorphisms, vitamin D, and clinical form was not significant. CONCLUSIONS: Decreased levels of vitamin D suggest an association with the cardiac form of CD. Studies investigating the roles of vitamin D and LL-37 in the immune response and their associations with VDR polymorphisms and disease susceptibility are necessary.

Evaluating respiratory musculature, quality of life, anxiety, and depression among patients with indeterminate chronic Chagas disease and symptoms of pulmonary hypertension

Abstract INTRODUCTION: Chagas disease (CD) is progressive and incapacitating, especially when cardiopulmonary function is affected. For example, respiratory muscle weakness can cause dyspnea upon exertion and fatigue, which may be exacerbated when it is associated with pulmonary hypertension (PH). The present study aimed to evaluate respiratory musculature, quality of life, anxiety, and depression among patients with indeterminate chronic CD and symptoms of PH. METHODS: All individuals completed a clinical evaluation, spirometry, a 6-min walking test, respiratory musculature testing using maximum inspiratory pressure (PImax) and maximum expiratory pressure (PEmax), the Hospital Anxiety and Depression Scale, and the SF-36 questionnaire. RESULTS: We evaluated 107 patients who were assigned to a control group with only CD (G1, 8 patients), a group with CD and possible PH (G2, 93 patients), and a group with CD and echocardiography evidence of PH (G3, 6 patients). The three groups had similar values for PImax and PEmax. Compared to the G1 and G2 groups, the G3 group covered significantly less distance during the 6-min walking test and had a significantly shorter predicted distance (p < 0.05 vs. the G1 group). All three groups had similar values for their spirometry results, Hospital Anxiety and Depression Scale scores, and SF-36 questionnaire results. CONCLUSIONS: Patients with indeterminate chronic CD and symptoms of PH did not experience significant impairment in the studied variables, with the exception of the 6-min walking test, which suggests a low exercise tolerance.