Structural and Ultrastructural Analysis of Cerebral Cortex, Cerebellum, and Hypothalamus from Diabetic Rats

Abstract

Autonomic and peripheral neuropathies are well-described complications in diabetes. Diabetes mellitus is also associated to central nervous system damage. This little-known complication is characterized by impairment of brain functions and electrophysiological changes associated with neurochemical and structural abnormalities. The purpose of this study was to investigate brain structural and ultrastructural changes in rats with streptozotocin-induced diabetes. Cerebral cortex, hypothalamus, and cerebellum were obtained from controls and 8 weeks diabetic rats. Light and electron microscope studies showed degenerative changes of neurons and glia, perivascular and mitochondrial swelling, disarrangement of myelin sheath, increased area of myelinated axons, presynaptic vesicle dispersion in swollen axonal boutoms, fragmentation of neurofilaments, and oligodendrocyte abnormalities. In addition, depressive mood was observed in diabetic animals. The brain morphological alterations observed in diabetic animals could be related to brain pathologic process leading to abnormal function, cellular death, and depressive behavioral.

Does allicin combined with vitamin B-complex have superior potentials than alpha-tocopherol alone in ameliorating lead acetate-induced Purkinje cell alterations in rats? An immunohistochemical and ultrastructural study

“…The myelin-like figures that appeared in the cytoplasm of the Purkinje cells in the current study agree with the findings observed in the neuronal body of the cerebellum in diabetic rats, which has been attributed to degenerated mitochondria [23].…”

Environmental enrichment exposure restrains the neuronal damage induced by diabetes and stress in the motor cortex of rat brain

“…Severe neuropathy causes thickening of axons, decreased microfi laments and capillary narrowing, which will lead to weakness and unbalanced walking (Tripathi and Srivastava, 2006).Structural and ultra-structural changes in the form of disarrangement of myelin sheath, degenerative changes of neurons and glia, presynaptic vesicle dispersion in swollen axonal bouttons, fragmentation of neurofi laments and oligodendrocyte abnormalities were observed in the cerebral cortex of streptozotocin (STZ) induced diabetic rats (Hernandez-Fonseca et al, 2009). …”

Protective role of coenzyme Q 10 against high cholesterol dietinduced histological and biochemical changes in cerebellar cortex of adult albino rats

“…Expanded perivascular space and perivascular swelling is similar to those observed in diabetic rats and could represent swollen pericytes, astrocytes, or adipocytes leading to disruption of the blood brain barrier (BBB) functions [41]. The generation of reactive oxygen species, in particular superoxide is thought to be a major factor in cholesterol's effects on dysfunction of the microvasculature [42].…”