人脂肪干细胞对放射线损伤大鼠唾液腺的修复作用

Effect of human adipose-derived stem cells on the repair of salivary glands in rats with radiation injury

目的探讨人脂肪干细胞(hADSCs)移植对于促进放射线损伤大鼠唾液腺分泌功能的修复作用。方法选取8周龄的SD大鼠60只,随机分成实验组、放射组和对照组,每组各20只。其中,实验组和放射组腹腔麻醉后颌下腺区域接受18 Gy X射线照射,对照组只麻醉不照射。照射后第2天实验组接受hADSCs移植(1×10 6个),放射组腺体内注射等体积的PBS溶液。照射后第8周测量各组颌下腺唾液流率,处死大鼠剖取颌下腺,4%多聚甲醛固定后制作石蜡切片,HE和TUNEL染色后镜下观察其组织形态。结果放射8周后对照组大鼠唾液流率为(20.77±5.16)μl/min,放射组大鼠唾液流率为(11.23±10.10)μl/min,实验组大鼠唾液流率为(15.92±5.41)μl/min。HE染色显示放射组颌下腺细胞变性水肿,部分细胞坏死,血管充血。实验组仅见部分细胞水肿和血管充血。TUNEL染色结果见放射组颌下腺内出现大量凋亡细胞,实验组颌下腺见少量凋亡细胞。结论hADSCs移植能够促进放射损伤大鼠唾液腺的分泌功能,其机制还需进一步研究。

Objective To investigate the effect of human adipose-derived stem cells(hADSCs) on rescuing radiation-damaged salivary gland of SD rats. Methods 60 8-week-old SD rats were set into 3 groups randomly(20 for each).Rats in the hADSC group(experimental group) and irradiated group(positive control group) accepted 18 Gy irradiation after anesthesia,the normal group(negative control group) were anesthetized only.At the second day post-irradiation,1×10 6 hADSCs were injected into the submandibular gland of the rats in the hADSC group,while same volume of PBS was administered to the irradiated group.All rats were sacrificed after saliva flow rate assessed at 8 week post-irradiated.Then submandibular glands were harvest.After paraffin section,hematoxylin-eosin and TUNEL staining were performed to observe morphology of salivary glands. Results 8 weeks after irradiation,saliva flow rate of hADSC group was (15.92±5.41)μl/min,while those of normal and irradiated group were (20.77±5.16)μl/min and (11.23±10.10)μl/min,respectively.Hematein-eosin staining displayed edema acinar cells together with cell necrosis and congestion of blood vessel in submandibular gland of irradiated group.And cellular swelling and congestion were observed in submandibular gland of hADSC group.TUNEL staining showed a large number of apoptotic cells in the submandibular gland of the radiation group,while a small number of apoptotic cells were seen in the submandibular gland of the experimental group. Conclusion Our research indicates that hADSCs has the potential to rescue the function of irradiation-damaged salivary gland.The mechanism should be further studied.