ULTRASTRUCTURAL CHANGES IN THE NEOCORTEX OF RATS WITH METABOLIC SYNDROME INDUCED BY A HIGH-CALORIE DIET

Abstract

Objective - to study the features of neocortex neuronal and glial reaction to chronic hyperglycemia and insulin resistance in rats with the metabolic syndrome (MS) induced by a high calorie diet. Material and methods. The study was performed on male Wistar rats (20 animals). The ultrastructure of I-VI layers of sensorimotor cortex of rats with MS induced by a 15 weeks high-calorie diet was studied by means of electron microscopy. The ultrastructural analysis of neurons and glial cells was carried out and the number of the neuron-neuron, neuron-glia and neuro-vascular contacts was counted. Results. In case of MS, a 13 % decrease in the proportion of normochromic neurons and a 5-fold increase in the proportion of apoptotic neurons were shown; the number of neuron-neuron contacts increased 1,5 times and the number of the neuro-vascular contacts increased 2,3 times compared with the control. The number of contacts of normochromic neurons with both hyperchromic neurons and hyperchromic glia increased in MS-rats, and polymorphic structural changes in the myelin sheaths were observed. Conclusions. In rats with metabolic syndrome induced by a high-calorie diet, the adverse ultrastructural changes in neurons and glial cells, and in neuron-neuron, neuron-glia and neurovascular contacts in the rat sensorimotor cortex were observed. It is assumed that these changes occur due to angiopathic hypoxia in conditions of systemic insulin resistance and hyperglycemia.

Keywords

neuron / glia / myelin / rat / metabolic syndrome / hyperglycemia

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RIGHTS & PERMISSIONS

Paramonova N.M., Chistyakova O.V., Sukhov I.B., Derkach K.V., Shpakov A.O.