A potential defense mechanism against amyloid deposition in cerebellum.

Amyloid-ß (Aß) is the major component of senile plaques in Alzheimer's disease (AD) brains. Senile plaques are generally observed in cerebral cortex (CTX) rather than cerebellum (CBL) in AD patients. However, it is not clear why CBL has less Aß deposition than CTX. It is very important to elucidate the mechanism of suppressing Aß deposition in CBL, because it contributes to understanding of not only AD pathogenesis but also prevention and cure of AD. In this study, we explored to figure out the potential mechanism of reducing Aß deposition in CBL. We observed higher age-dependent elevation of Aß level in CTX rather than CBL of human APP knock-in AD model mice, although we detected no significant differences in the levels of interstitial fluid Aß in these brain tissues. These data imply that less Aß deposition in CBL is due to enhanced Aß clearance rather than altered Aß production in CBL. To gain insights into Aß clearance in CBL, we injected fluorescence-labeled Aß in brain tissues. Importantly diffusion area of fluorescent Aß in CBL was roughly six-times larger than that in CTX within 2 h of injection. In addition, injected Aß area in CBL decreased sharply after 24 h and CBL-injected Aß was robustly detected in deep cervical lymph nodes (DcLNs). In contrast, diffusion area of fluorescent Aß in CTX was consistent up to 72 h and CTX-injected Aß was faintly detected in DcLNs. Our data suggest that enhanced Aß drainage in association with meningeal lymphatic system is responsible for less Aß deposition in CBL.

In vivo analysis of toxic effect of hydrose used in food preparations in Bangladesh

Objective: To evaluate the toxic effect of hydrose used in the molasses preparation in Bangladesh. Methods: Molasses were collected from open markets in different parts of Bangladesh. The presence of hydrose in selected molasses was detected using commercial kit. To evaluate the toxic effect of hydrose, Swiss albino male mice were divided into four groups. Group I was used as control, while Groups II, III and IV received hydrose mixing food (5, 10 and 25 g/ kg food), respectively, and these supplementations were continued to the end of the study (16 weeks). Blood was collected from thoracic arteries of the mice under ether anesthesia and then organs were taken. To determine the effect of hydrose on host, blood indices related to liver, heart and kidney dysfunctions were measured. Result: Creatinine and urea levels were significantly (P < 0.05) increased in a dose dependent manner in hydrose treated mice, whereas calcium level was significantly decreased in hydrose exposed mice compared to control mice. Histological study of kidney showed the glomeruler inflammation, increased diameter of renal glomeruli and enlargement of proximal tubular lumen of kidneys of mice exposed to hydrose compared to that of control animals. Conclusion: The results of this study indicated that use of hydrose in molasses and other food preparations in Bangladesh may cause kidney impairment.