Lingzhi or Reishi Medicinal Mushroom, Ganoderma lucidum (Agaricomycetes) Ameliorates Spatial Learning and Memory Deficits in Rats with Hypercholesterolemia and Alzheimer's Disease

Hypercholesterolemia has been implicated as one of the pathomechanistic factors of Alzheimer's disease (AD), the most common neurodegenerative disorder affecting memory and learning abilities. In the present study, ameliorative effect of hot water extract (HWE) of mushroom Ganoderma lucidum to the memory and learning related behavioral performance of hypercholesterolemic and AD rats was investigated using Morris water maze (MWM). Male Wistar rats were randomly grouped into control, extract fed control, hypercholesterolemic, extract fed hypercholesterolemic, AD, and extract fed AD groups, each group containing 8 animals. Hypercholesterolemia was induced in rats by adding 1% cholesterol and 1% cholic acid with the basal diet of the respective group. Alzheimer's disease model rats were prepared through infusion of amyloid β(1-42) to the right ventricle. Memory and learning related performance of all the rats was tested for 6 consecutive days that included time taken to reach the submerged platform (sec) and distance traveled (m). G. lucidum HWE fed rats took less time and traveled less distance to find the submerged platform, which indicates the spatial learning and memory related behavioral amelioration of the extract fed rats compared with their non-fed counterparts. Thus, usage of G. lucidum seems promising in withstanding hypercholesterolemia-induced Alzheimer's disease pathogenesis.