Relationship between cortisol, Interleukin-6 and homocysteine in Alzheimer's disease.

OBJECTIVE: Alzheimer's disease (AD) is characterised by progressive cognitive decline due to neurodegeneration. Over activation of the hypothalamic-pituitary-adrenal axis, oxidative stress and inflammation potentially damage the neuronal system, affecting cognition. AIM: This study aimed to assess the relationship between serum cortisol, Interleukin-6 (IL-6) and homocysteine (Hcy) levels in AD. METHODS: Case-Control observational study consisting of 71 patients with AD and 70 healthy controls above 60 years of age. Serum samples were analysed for cortisol, IL-6 and Hcy levels using chemiluminescence immunoassay (Immulite 1000) technique. Cognitive functions were measured using the Mini-Mental State Examination (MMSE) Score. AD subjects were categorised based on the modified Kuppuswamy socioeconomic status scale. Statistical evaluation was conducted using SPSS Statistics software. Group data were analysed using a two-tailed Student's t-test, analysis of variance (ANOVA), the Mann-Whitney U test and Pearson's correlation test. RESULTS: Serum cortisol, IL-6 and Hcy levels were significantly increased (p < 0.01) in AD (cortisol: 19.69 ± 8.96 ug/dl; IL-6: 10.27 ± 2.76 pg/ml; Hcy: 23.29 ± 3.81 µmol/l), as compared with the controls (cortisol: 13.37 ± 5.59 ug/dl; IL-6: 3.37 ± 0.79 pg/ml; Hcy: 8.25 ± 2.36 µmol/l). MMSE scores in AD were negatively correlated with cortisol, IL-6 and Hcy levels. CONCLUSIONS: Serum cortisol, IL-6 and Hcy levels are independent biomarkers for AD progression. Hypercortisolaemia, hyperhomocysteinemia and inflammation play important roles in AD-related cognitive dysfunction and are interlinked.

Study of IL-6 and vitamin D3 in patients of pulmonary tuberculosis.

BACKGROUND: Mycobacterium tuberculosis can grow in hostile intracellular environment of macrophages by actively evading macrophage-associated antibacterial activities. The stress response factor contributes this process by releasing inflammatory cytokine Interleukin 6 (IL-6). IL-6 screening of patients with TB may be useful to monitor the progress of infection and to infer the risk of progression to active disease. Vitamin D has a critical role in the innate immune system, in the circulating metabolite and supports induction of pleiotropic antimicrobial responses, through the production of antimicrobial peptides, particularly cathelicidin and its active metabolite. 1,25-dihydoxyvitamin D, has long been known to enhance immune response to mycobacteria. In this study, we have studied the role of IL-6 and Vitamin D3 in M. tuberculosis. MATERIALS AND METHODS: Three groups involved in this study are Control, Category I (newly diagnosed TB) and MDR TB patients. The serum levels of IL-6 and vitamin D3 were measured using chemiluminescence and fully-automated enzyme-linked immunosorbent assay respectively. RESULTS: The serum levels of IL-6 were significantly increased, whereas vitamin D3 decreased in TB multidrug-resistant group of patients compared to the newly diagnosed TB patients. CONCLUSION: IL-6 appears to be the major cytokine elaborated by mycobacteria infection as well as play a role in the clinical manifestations and pathological events and hence may function as a potent biomarker of tuberculosis. Since, Vitamin D increases activity of cell-mediated immunity; it can be used as a supplementation during tuberculosis therapy.