To Investigate The Protective Effects And Mechanisms Of Capsaicin On Rat Submandibular Gland Damaged By Radioiodine-131 In Early Phase

Objective: The quality of life for patients can be decreased due to irreversible oral complaints,which caused by radiation damage in salivary gland after 131 iodine(131I)therapy to thyroid cancer.Life pepper can promote the secretion of saliva,so the aim of the current was to investigated the effect of capsaicin on the irradiated submandibular gland and the potential mechanisms.Material and methods: 24 wistar rats,were randomly divided into four groups: the control group,the capsaicin only group,the 131 I treated only group,the capsaicin treatment after 131 I administration group.131I(5 mci/kg)was intraperitoneally injected to rats.An amount of 0.2 g of capsaicin cream was spread over the skin covering the submandibular gland twice a day.The submandibular glands were removed on day 7 after 131 I administration and weighted after surgery.To observe the acinar cell morphology by hematoxylin and eosin staining.We used the Tunel method to detect the number of apoptotic cells.The PCNA(Proliferating Cell Nuclear Antigen),Bax,Cleaved-Caspase 3 and NAMPT expression in submandibular glands were detected by immunohistochemistry,and the immunopositive values were expressed in terms of integrated optical intensity.Western blot was used to detected the expression level of NAMPT protein.In clinical,we recruited 15 patients who would receive the iodine therapy due to thyroid cancer.After iodine administration,the capsaicin was applied on the skin covering the submandibular gland.Salivary gland scintigraphy was used to detect the function on day 180 after 131 I administration.Result: 1.Capsaicin could prevent weight loss caused by iodine radiation damage in submandibular gland.2.Our current study demonstrated that the capsaicin could decrease the atrophy of submandibular gland acinar cellular.3.The number of the apoptotic cell in the capsaicin treatment after 131 I administration group was less than the 131 I treated only group.4.The expression of Cleaved-Caspase 3 and Bax was decreased in the capsaicin treatment after 131 I administration group when compared with the 131 I treated only group and capsaicin could promote the expression of PCNA in irradiated submandibular gland.5.In the 131 I treated only group,the expression level of NAMPT was decreased when compared with the control group.In the comparison with the 131 I treated only group,the expression level of NAMPT were increased in the capsaicin treatment after 131 I administration group.6.In clinical,we found that capsaicin could prevent or mitigate damage to submandibular gland function due to radiation.Conclusion: The capsaicin could play protective effect on the irradiated submandibular gland,and the protective mechanism might be related to the expression level of NAMPT.To explore the effect of capsaicin on the irradiated submandibular gland could provide a new and safe method to protect the submandibular gland of patients who would receive the 131 I therapy due to thyroid cancer.