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.