Consumption of green tea alters glial fibriliary acidic protein immunoreactivity in the spinal cord astrocytes of STZ-diabetic rats

Abstract

We examined the effect of green tea consumption on glial fibriliary acidic protein (GFAP) expression in spinal cord of streptozotocin (STZ) treated rats. Three groups (n = 10) were used in this study: (i) controls; (ii) STZ-induced diabetic rats given tap water; and (iii) an STZ-induced diabetic group given green tea. Immunohistochemistry showed a significant (P < 0.001) decrease in the number of GFAP immunoreactive astrocytes in spinal cord sections of diabetic rats compared to non-diabetic controls. Diabetic rats treated with green tea showed a significant (P < 0.01) increase in the number GFAP-immunoreactive astrocytes in all the spinal cord gray areas as compared to water-drinking diabetic rats. Immunoblotting confirmed that the diabetic spinal cord tissue expressed 71.0 ± 7.0% less GFAP compared to non-diabetic controls and that the GFAP content in diabetic rats increased up to 86.34 ± 18.74% compared to non-diabetic controls after 12 weeks of green tea consumption. In conclusion, consumption of green tea may represent an achievable adjunct therapy for improving changes seen in diabetic spinal cord.