الفهرس 
Introduction and aim of the work
Diabetes mellitusOnly 14 pages are availabe for public view
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Abstract
The protective effect of B complex vitamins from the development of DN of sciatic nerve have been studied in streptozotocin diabetic rats.
A total number of 30 adult male albino rats were used and divided into two groups; I, II. GroupI served as control. group II; were rendered diabetic and were further subdivided into two subgroups; IIa, IIb. Diabetes was induced by a single intraperitoneal injection of streptozotocin(STZ) at a dose of 80mg/kg. group IIa were kept for 6 weeks without further treatment. group IIb received vitamin B complex intraperitoneally in a single daily dose of 180mg/kg for 6 weeks.
The sciatic nerve was dissected out and small specimens were taken and prepared for light and electron microscopic examination. The morphological changes were confirmed with immunohistochemistry using CD31, CD68 and anticaspase 3 antibodies. Also four morphological indices were measured. These included the average myelin sheath thickness, the average myelinated nerve fiber area, endoneurial capillary density and perineurial index.
Schwann cells from group IIa showed pathological abnormalities which varied from activation in the form of abundant Golgi bodies and thickened basal lamina to signs of degeneration as marked decrease in cytoplasmic organelles, features of apoptosis (margination of the nuclear chromatin, condensed nucleus and dark appearance of the cytoplasm). Apoptosis was verified using anticaspase 3 antibodies which also revealed apoptotic perineurial cells.
Nerve fibers pathological changes consisted mainly of axonal atrophy, myelin splitting, and infolding and fiber atrophy. Morphometric indices revealed decrease in myelinated nerve fiber area as well as myelin sheath thickness compared to the control group.
We demonstrated endoneurial microangiopathy characterized by BM thickening, endothelial cells proliferation and fenestration and collapse.Pathology of endothelial cells was confirmed by immunohistochemistry which revealed their -ve staining with CD31.Furthermore, there was significant decrease in endoneurial capillary density compared to the control group.
Occasionally, mast cells were detected in semithin sections stained by toluidine blue stain and by ultrastructure.
A positive effect of vitamin B complex was observed on sciatic nerve. Schwann cells and perineurial cells are protected from the apoptotic changes observed in diabetic rats. Furthermore, vitamin B complex was able to counteract the pathological changes observed in nerve fibers of the diabetic group reducing the process of demyelination and axonal atrophy and the nerve fibers revealed an appearance which was more or less similar to the control.
Additionally vitamin B complex prevented the morphological deficit occurred in endoneurial blood capillaries. Endoneurial blood capillaries had patent lumen, with endothelial lining and basement membrane thickness as the control group.There was positive staining of endothelial cells with CD31 on the contrary to the negatively stained cells in diabetic group.
A significant improvement in myelin sheath thickness and perineurial index has been exerted by vitamin treatment but the nerve fiber area failed to be significantly increased. An interesting finding in our study was the significant increase in endoneurial capillary density under the vitamin treatment.
Endoneurial perivascular phagocytic cells were detected in ultrastructure in groups IIa and IIb, with preponderance in group IIb. These cells revealed positive immune reaction for CD31 and CD68.
Conclusion
B complex vitamins prevented many of the morphological deficits which occurred in sciatic nerve under the influence of diabetes. vitamin B complex supplementation might provide a safe, long-term, inexpensive, readily available and well-tolerated drug approach for protection from diabetic neuropathy.