Neuroprotective Effects of OMO within the Hippocampus and Cortex in a <scp>D</scp>‐Galactose and A<i>β</i><sub>25–35</sub>‐Induced Rat Model of Alzheimer’s Disease
Shaodong Deng, Hongmei Lu, Honggang Chi, Ying Wang, Xiao Li, Haiyi Ye
Abstract
Morinda officinalis F.C. How. (Rubiaceae) is a herbal medicine. It has been recorded that its oligosaccharides have neuroprotective properties. In order to understand the oligosaccharides extracted from Morinda officinalis (OMO), a systematic study was conducted to provide evidence that supports its use in neuroprotective therapies for Alzheimer’s disease (AD). AD rat models were prepared with D ‐galactose and A β 25–35 . The following groups were used in the present experiment: normal control group, sham‐operated group, model group, Aricept group, OMO low‐dose group, OMO medium‐dose group, and OMO high‐dose group. The effects on behavioral tests, antioxidant levels, energy metabolism, neurotransmitter levels, and AD‐related proteins were detected with corresponding methodologies. AD rats administered with different doses of OMO all exhibited a significant ( P < 0.05) decrease in latency and an increase ( P < 0.05) in the ratio of swimming distance to total distance in a dose‐dependent manner in the Morris water maze. There was a significant ( P < 0.05) increase in antioxidant enzyme activities (SOD, GSH‐Px, and CAT), neurotransmitter levels (acetylcholine, γ ‐GABA, and NE and DA), energy metabolism (Na + /K + ‐ATPase), and relative synaptophysin (SYP) expression levels in AD rats administered with OMO. Furthermore, there was a significant ( P < 0.05) decrease in MDA levels and relative expression levels of APP, tau, and caspase‐3 in AD rats with OMO. The present research suggests that OMO protects against D ‐galactose and A β 25–35 ‐induced neurodegeneration, which may provide a novel strategy for improving AD in clinic.