This study was designed to evaluate the neuroprotective effects of Morinda citrifolia L. (Rubiaceae), commonly known as noni, and memantine (a N-methy-D-aspartate receptor inhibitor) on hydrocephalus-induced neurodegenerative disorders. Kaolin was injected into the cistern magna of male adult New Zealand rabbits to establish a hydrocephalus animal model. Memantine (20 mg/kg, intraperitoneally; memantine-treated group) or noni (5 mL/kg, intragastrically; noni-treated group) was administered daily for 2 weeks. Microtubule-associated protein-2 and caspase-3 immunohistochemistry were performed to detect neuronal degeneration and apoptosis in the periventricular tissue of the fourth ventricle of rabbits. Microtubule-associated protein-2 staining density was significantly decreased in the hydrocephalic group, while the staining density was significantly increased in the memantine- and noni-treated groups, especially in the noni-treated group. Noni treatment decreased the number of caspase-3-positive cells in rabbits with hydrocephalus, while memantine had no effect. These findings suggest that noni exhibits more obvious inhibitory effects on hydrocephalus-induced neurodegenerative disorders than memantine in periventricular tissue of the fourth ventricle.Research Highlights
(1) Morinda citrifolia L. (Rubiaceae), known as noni, has been extensively used in folk medicine in Polynesia and tropical parts of eastern Asia and Australia, and contains some antioxidative or anti-inflammatory ingredients.Research Highlights
(2) This study monitored the microtubule-associated protein-2, a major component of the cytoskeleton, and the upregulation of caspase-3 as detection indices to validate that noni and memantine protect against hydrocephalus-induced neurodegenerative disorders.Research Highlights
(3) Memantine, a N-methyl-D-aspartate receptor inhibitor, has been used for the treatment of Alzheimer's disease. Results from this study demonstrate that memantine can alleviate hydrocephalus-induced neurodegenerative disorders.Research Highlights
(4) Noni exhibits more obvious inhibitory effects on hydrocephalus-induced neurodegenerative disorder than memantine in periventricular tissue of the fourth ventricle.