Alzheimer's disease (AD) is the leading neurodegenerative disorder affecting memory and learning of aged people. Hypercholesterolemia had been implicated as one of the stark hallmarks of AD. Recent AD control guidelines have suggested lifestyle modification to slow down the progression of AD. In this regard, medicinal mushroom Ganoderma lucidum seems apt. In the present study, hot water extract of G. lucidum (200 mg/kg body weight) was fed to the hypercholesterolemic and AD model rats for 8 weeks. Nonspatial memory and learning abilities of the model animals was assessed using novel object recognition (NOR) test, rotarod test, and locomotor/open-field test. Then, the animals were sacrificed and transmission electron micrograph (TEM) view of the hippocampal neurons was assessed. In all the nonspatial memory and learning tests, the G. lucidum HWE fed rats performed better indicating improved memory and learning abilities. TEM view showed regular arrangement of the neurons in the G. lucidum HWE fed rats compared with those of the deranged arrangement of the AD rats. G. lucidum might have aided in restoring the memory and learning abilities of the AD model animals through maintaining neuronal structure and function. Thus, G. lucidum could be suggested as a medicotherapeutic agent against AD.
This study assessed the cholesterol lowering effect of Pediococcus acidilactici LAB4 and Lactobacillus plantarum LAB12 using adult zebrafish. Animals were fed with a high cholesterol diet (HCD) with/without LAB for seven weeks. Serum and liver cholesterol was quantified using colorimetric and dye staining methods. Expressions of npc1l1 and abca1 in the liver and intestine and appa in the brain were quantified using RT-PCR. Serum and liver cholesterol was significantly lowered in LAB4- and LAB12-fed zebrafish (≤64% and ≤71%, respectively), with reduced liver cholesterol deposition. The cholesterol lowering effect was accompanied by down-regulation of npc1l1 in intestines (≤28.7%), up-regulation of abca1 in the liver (≥30.5%) and down-regulation of appa in the brain (≤24.5%). A moderately strong positive Pearson correlation (r = 0.617, p < 0.01) was found between appa and serum cholesterol. LAB-fed zebrafish exhibited improved spatial learning and memory. LAB4 and LAB12 can be potentially used in preventing hypercholesterolaemia and Alzheimer's diseases.