Dark neurons in the ageing cerebellum: their mode of formation and effect of Maharishi Amrit Kalash

• Published in: Biogerontology (Dordrecht) 2002-01, Vol.3 (6), p.347-354
• Main Authors: VOHRA, B. P. S, JAMES, T. J, SHARMA, S. P, KANSAL, V. K, CHUDHARY, A, GUPTA, S. K
• Format: Article
• Language: English
• Subjects: Aging - physiology; Animals; Biological and medical sciences; Cerebellum - cytology; Cerebellum - drug effects; Development. Senescence. Regeneration. Transplantation; Fundamental and applied biological sciences. Psychology; Guinea Pigs; Hogs; Lipid Peroxidation; Lipids; Male; Medicine, Ayurvedic; Microscopy, Electron; Neurons - cytology; Neurons - drug effects; Neurons - physiology; Neurons - ultrastructure; Plant Preparations - pharmacology; Proteins; Rats; Vertebrates: nervous system and sense organs
• ISSN: 1389-5729; 1573-6768
• DOI: 10.1023/A:1021303415191

Dark neurons are considered a manifestation of neuronal injury and although they cover various grades of damage their mode of formation is not yet clear. Age-dependent alterations in a dark purkinje neuronal population of guinea pigs (10 months and 32 months old) and rats (3 months, 6 months, 12 months, 15 months and 28 months) were studied. Light microscopical and electron microscopical observations revealed a significant increase (P < 0.05) in the number of dark purkinje neurons with age in both the guinea pigs and rats. Extraction of lipids from the cerebellum sections before processing for histochemical reaction resulted in a reduction of the dark neuronal population. In an other set of experiments, significant age-dependent increase in the cathepsin-D activity and lipid peroxidation was documented in the guinea pig cerebellum. Treatment of guinea pigs with Maharishi Amrit Kalash (MAK) (500 mg/kg body wt/day, for two months) significantly inhibited (P < 0.05) the activity of cathepsin-D and lipid peroxidation, and decreased the number of dark neurons. These findings suggest that the number of dark neurons increases with age and MAK prevents the conversion of light to dark purkinje neurons due to its inhibitory effects on cathepsin-D activity and antioxidant properties. We suggest that the conformational changes in the normal protein structure due to higher proteolytic activity and peroxidation of lipid in the aging cerebellum endangers a redundant capability for various staining agents and the Osimic acid molecules to react with proteins, lipids and other molecules, leading to an intensified cyto- and karyoplasms electron density.