ULTRASTRUCTURAL CHANGES OF THE MESENTRIC LYMPH NODES OF CALVES EXPERIMENTALLY INFECTED WITH SALMONELLA TYPHIMURIUM

A systemic study was done on the pathogenesis of experimentally induced Salmonella typhimurium infection in calves. The present investigation was carried out on sixteen normal colostrum fed friesian calves, ranging in age from 3 to 6 weeks. The calves were divided into two equal groups. Group I inoculated orally with (1.5 x 10'') Salmonella typhimurium and group IA served as control. • The early ultrastructural alteration in the mesenteric lymph nodes was the presence of many free Salmonella in localized vacuoles. The interaction between the host cells and phagocytized Salmonella was also observed.

Protective Effects of Centella asiatica on Cognitive Deficits Induced by D-gal/AlCl3 via Inhibition of Oxidative Stress and Attenuation of Acetylcholinesterase Level

Alzheimer’s disease (AD) is a progressive neurodegenerative disorder with cholinergic dysfunctions and impaired redox homeostasis. The plant Centella asiatica (CA) is renowned for its nutritional benefits and herbal formulas for promoting health, enhancing cognition, and its neuroprotective effects. The present study aims to investigate the protective role of CA on D-gal/AlCl3-induced cognitive deficits in rats. The rats were divided into six groups and administered with donepezil 1 mg/kg/day, CA (200, 400, and 800 mg/kg/day) and D-gal 60 mg/kg/day + AlCl3 200 mg/kg/day for 10 weeks. The ethology of the rats was evaluated by the Morris water maze test. The levels of acetylcholinesterase (AChE), phosphorylated tau (P-tau), malondialdehyde (MDA) and activities of superoxide dismutase (SOD), in the hippocampus and cerebral cortex were estimated by enzyme-linked immunosorbent assay (ELISA). Additionally, the ultrastructure of the prefrontal cortex of the rats’ was observed using transmission electron microscopy (TEM). Rats administered with D-gal/AlCl3 exhibited cognitive deficits, decreased activities of SOD, and marked increase in AChE and MDA levels. Further, prominent alterations in the ultrastructure of the prefrontal cortex were observed. Conversely, co-administration of CA with D-gal/AlCl3 improved cognitive impairment, decreased AChE levels, attenuated the oxidative stress in hippocampus and cerebral cortex, and prevented ultrastructural alteration of neurons in the prefrontal cortex. Irrespective of the dose of CA administered, the protective effects were comparable to donepezil. In conclusion, this study suggests that CA attenuated the cognitive deficits in rats by restoring cholinergic function, attenuating oxidative stress, and preventing the morphological aberrations.

Retromer has a selective function in cargo sorting via endosome transport carriers

Retromer is a peripheral membrane protein complex that coordinates multiple vesicular trafficking events within the endolysosomal system. Here, we demonstrate that retromer is required for the maintenance of normal lysosomal morphology and function. The knockout of retromer subunit Vps35 causes an ultrastructural alteration in lysosomal structure and aberrant lysosome function, leading to impaired autophagy. At the whole-cell level, knockout of retromer Vps35 subunit reduces lysosomal proteolytic capacity as a consequence of the improper processing of lysosomal hydrolases, which is dependent on the trafficking of the cation-independent mannose 6-phosphate receptor (CI-M6PR). Incorporation of CI-M6PR into endosome transport carriers via a retromer-dependent process is restricted to those tethered by GCC88 but not golgin-97 or golgin-245. Finally, we show that this retromer-dependent retrograde cargo trafficking pathway requires SNX3, but not other retromer-associated cargo binding proteins, such as SNX27 or SNX-BAR proteins. Therefore, retromer does contribute to the retrograde trafficking of CI-M6PR required for maturation of lysosomal hydrolases and lysosomal function.

Effect of Potentilla Fulgens L. on Selected Enzyme Activities and Altered Tissue Morphology in Diabetic Mice

Introduction The objective of the present study was to investigate the in vitro inhibitory effect of the Potentilla fulgens extract on amylase, α- and β-glucosidase, and lipase, as well as its effect on the ultrastructure of the liver, of the kidneys, and of the eye tissues in alloxan-induced diabetic mice. The present study was designed to get further insight regarding the action of P. fulgens from what has been previously known and reported about this plant. Materials and Methods Roots of P. fulgens were extracted with 10 volumes of aqueous-methanol solution (1:4), and the prepared extract was used for in vitro inhibitory activity on amylase, α-glucosidase, β-glucosidase, and lipase. Afterwards, the plant extract was intraperitoneally administered for alternated days (250 mg/kg body weight) to diabetic mice for 4 weeks, and an ultrastructural examination of the liver, the kidneys and the eye tissues was performed using a transmission electron microscope (JEM-100 CX II, Jeol Ltd., Tokyo Japan). Results The P. fulgens extract showed inhibitory activity against all the four enzymes (amylase, α- and β-glucosidase, and lipase), with the highest percentage of inhibition (94.57% ± 0.16 at 1 mg/mL) being observed against α-glucosidase when compared with the standard. The ultrastructural studies revealed a distortion in the structure of the nuclei and of the mitochondria in the kidneys and liver tissues of diabetic mice. Distortion of cell shape and disturbed orientation was observed in the eye lens of diabetic mice. The P. fulgens extract reversed/protected/reduced the ultrastructural alteration observed in the tissues (liver, kidney, and eye lens) of diabetic mice. Conclusion The inhibitory effect of the P. fulgens extract against the aforementioned enzymes and its protective effect on the tissues of diabetic mice against alloxan-induced diabetes add further insight into the antidiabetic properties of this plant.