Sericin protects against diabetes-induced injuries in sciatic nerve and related nerve cells

Sericin from discarded silkworm cocoons of silk reeling has been used in different fields,such as cosmetology,skin care,nutrition,and oncology.The present study established a rat model of type 2 diabetes by consecutive intraperitoneal injections of low-dose (25 mg/kg) streptozotocin.After intragastrical perfusion of sericin for 35 days,blood glucose levels significantly declined,and the expression of neurofilament protein in the sciatic nerve and nerve growth factor in L4-6 spinal ganglion and anterior horn cells significantly increased.However,the expression of neuropeptide Y in spinal ganglion and anterior horn cells significantly decreased in model rats.These findings indicate that sericin protected the sciatic nerve and related nerve cells against injury in a rat type 2 diabetic model by upregulating the expression of neurofilament protein in the sciatic nerve and nerve growth factor in spinal ganglion and anterior horn cells,and downregulating the expression of neuropeptide Y in spinal ganglion and anterior horn cells.