Previous studies have shown that sericin extracted from silk cocoon significantly reduces blood glucose levels and protects the nervous system against diabetes mellitus. In this study, a rat type 2 diabetes mellitus model was established by intraperitoneal injection of 25 mg/kg streptozotocin for 3 successive days, following which the rats were treated with sericin for 35 days. After treatment, the blood glucose levels of the diabetic rats decreased significantly, the growth hormone level in serum and its expression in the hippocampus decreased significantly, while the insulin-like growth factor-1 level in serum and insulin-like growth factor-1 and growth hormone receptor expression in the hippocampus increased significantly. The experimental findings indicate that sericin improves disorders of the growth hormone/insulin-like growth factor 1 axis to alleviate hippocampal damage in diabetic rats.
Keywords: blood glucose; grants-supported paper; growth hormone; growth hormone receptor; growth hormone/insulin-like growth factor 1 axis; hippocampus; insulin-like growth factor 1; neural regeneration; neuroregeneration; reverse transcription-PCR; sericin; streptozotocin; traditional Chinese medicine; type 2 diabetes mellitus; western blot assay.