卵巢细胞微囊移植对去卵巢小鼠的骨胶原代谢的影响

Allograft of microencapsulated ovarian cells affects bone collagen metabolism in ovariectomized mice

背景:性激素对维持骨骼的完整性是必要的,体外培养的卵巢细胞可以分泌雌激素和孕激素,海藻酸-多聚赖氨酸-海藻酸钠微球可以在移植物和受体间提供一个屏障,有利于异体移植物的存活。目的:探讨异体移植的微囊化卵巢细胞在去卵巢小鼠体内的生存和分泌功能,以及对骨胶原代谢的作用。方法:用6周龄雌性昆明小鼠分离培养卵巢细胞,并用海藻酸-多聚赖氨酸-海藻酸钠盐微囊化分离培养的卵巢细胞。将24只8周龄雌性昆明小鼠随机分为3组(n=8),正常组:未进行卵巢切割;去卵巢组:切除卵巢;移植组:卵巢切除后立即将微囊化的卵巢细胞移植入腹腔。射免疫分析法检测微囊化卵巢细胞培养液和小鼠血清雌二醇和/或孕激素水平,VanGieson染色法显示骨基质中的Ⅰ型胶原纤维,测小鼠左侧股骨羟脯氨酸、钙和磷的含量。结果与结论:卵巢细胞和微囊化卵巢细胞培养液中分泌雌二醇和孕激素水平没有显著差异,移植90d后小鼠血清雌二醇浓度与正常组无显著差异,而去卵巢组血清雌二醇浓度明显低于正常组。VanGieson染色显示,移植组的胶原纤维分布与正常组相似,而去卵巢组的骨小梁减少、游离末端增多,脱钙骨基质变薄,胶原纤维减少。与正常组比较,去卵巢组小鼠左侧股骨羟脯氨酸、钙和磷的含量降低。提示,微囊化卵巢细胞异体移植后能继续生存并分泌雌激素,并能在某种程度上减缓由去卵巢引起的骨胶原的分解代谢。

BACKGROUND： Gonad hormones are essential for the maintenance of skeletal integrity. The in vitro cultured ovarian cells can secrete estradiol and progesterone. Alginic acid-polylysine-alginic acid microcapsule provides a barrier between the graft and the recipient, thus promoting the survival of heterotransplants. OBJECTIVE： To explore the survival and secretion functions of allografted microencapsulated ovarian cells in ovariectomized mice and their effect on bone collagen metabolism after ovariectomy （OVX）. METHODS： Ovarian cells separated from female Kunming mice （6 weeks old） were cultured and microencapsulated with alginic acid-polylysine-alginic acid. A total of 24 female Kunming mice （8 weeks old） were randomly divided into three groups （n=8）： normal group： OVX was not performed; OVX group： OVX was performed; transplantation group： microencapsulated ovarian cells were transplanted into abdominal cavity after OVX. Estradiol and/or progesterone levels of the medium of microencapsulated ovarian cells and mice serum were determined by radioimmunoassay. Ⅰ type collagen fibers in the bone matrix were showed by Van Gieson staining. The concentrations of hydroxyproline, Ca, and P were measured in the left femurs of mice. RESULTS AND CONCLUSION： The concentrations of estradiol and progesterone in the culture medium were not significantly different between the cultured ovarian cells and microencapsulated ovarian cells. The serum estradiol concentration at 90 days after transplantation had no significant difference compared with that of normal group, whereas the serum estradiol concentration of the OVX group was significantly lower than that of the normal group. In the transplantation group, the distribution of collagen fibers was similar to that of the normal group determined by Van Gieson staining. In comparison to the normal group, the OVX group had less, thinner trabecular matrix, and fewer collagen fibers, more free trabecular terminals, and a thinner uncalcified osteoid matrix. The concentrations of Hyp, Ca, and P in the left femurs of the OVX group were lower than those of the normal group. Microencapsulated ovarian cells survive well after transplantation and secrete estrogen, and they can prohibit OVX-caused bone collagen fibers catabolism to some degree.