Cell Apoptosis of Taste Buds in Circumvallate Papillae in Diabetic Rats

Abstract

Diabetes mellitus may result in taste disturbance. The present study has revealed that cell apoptosis of taste buds in circumvallate papillae may contribute to the taste disturbance in a rat model of type2 diabetes. Type2 diabetes was induced in Wistar rats by feeding them with a high-fat diet (30% fat), and a single intraperitoneal injection of streptozotocin (30 mg/kg). The increased cell apoptosis of taste buds in circumvallate papilla sections was detected by TUNEL staining in diabetic rats, and the ultrastructure was further examined by transmission electronic microscopy. Immunohistochemical and Western blot analyses revealed the downregulation of Bcl-2, upregulation of Bax, and increased activation of caspase-9 and -3, in diabetic rats, indicating that the apoptosis of taste bud cells may be mediated via the intrinsic mitochondrial pathway in diabetics.

type 2 diabetes - taste buds - apoptosis - bcl-2 - caspase

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