Participation of Central Muscarinic Receptors on the Nervous Form of Chagas Disease in Mice Infected via Intracerebroventricular with Colombian Trypanosoma cruzi Strain.

Acute chagasic encephalitis is a clinically severe central nervous system (CNS) manifestation. However, the knowledge of the nervous form of Chagas disease is incomplete. The role of the muscarinic acetylcholine receptor (mAChR) on mice behavior and brain lesions induced by Trypanosoma cruzi (Colombian strain) was herein investigated in mice treated with the mAChR agonist and antagonist (carbachol and atropine), respectively. Immunosuppressed or non-immunosuppressed mice were intracerebroventricularly (icv) or intraperitoneally (ip) infected. All groups were evaluated 15 d.p.i. (days post infection). Intraperitoneally infected animals had subpatent parasitemia. Patent parasitemia occurred only in icv infected mice. The blockade of mAChR increased the parasitemia, parasitism and lesions compared to its activation. Infected not treated (INT ip) mice did not present meningitis and encephalitis, regardless of immunosuppression. INT icv brains presented higher cellularity, discrete signs of cellular degeneration, frequent presence of parasites and focal meningitis. The immunosuppressed atropine + icv mice presented increased intracellular parasitism associated with degenerative parenchymal changes, while carbachol + icv mice presented discrete meningitis, preservation of the cortex and absence of relevant parasitism. Cholinergic receptor blockage increased impairment of coordination vs. receptor activation. Muscarinic cholinergic pathway seems to be involved in immune mediated cell invasion events while its blockade favored infection evolution, brain lesions, and behavioral alterations.

Resistance training with blood flow restriction and cognition in elderly women (project "forte-mente-ativa"): study protocol

Abstract Aim: In the process of aging, there is a decrease on muscle strength and cognitive function. Resistance training combined with blood flow restriction (BFRRT) has been shown capable of maintaining or improve aspects of physical health. However, the effects of BFRRT the cognitive function of the elderly are not clear. This study aimed to describe the design of a randomized controlled clinical trial, that will investigate the effects of BFRRT on cognitive function, physical performance and physiological and morphological aspects in elderly women. Methods: Forty participants will be randomized into one of the following groups: low load resistance training, blood flow restriction resistance training, moderate load resistance training or Control. All intervention groups will complete 16 weeks of resistance training, three times week (45 minutes each), with training consisting of four exercises for the upper and lower body, including three sets of ten repetitions each. No exercise will be performed by the Control group. Cognitive function will be the primary outcome of the study. Secondary outcomes will include body composition, muscle strength, functional capacity, double-task, level of physical activity, static and dynamic balance, brain activity, BDNF neurotrophic factor, anxiety, depression and sleep state). Conclusion: This project will contribute to the existing knowledge and will have a social impact regarding the use of physical exercise as a non-pharmacological tool for the mental and physical health older individuals. Trial Registration: Brazilian Registry of Clinical Trials number RBR-7BC8ZP.