补肾活血方促进脂肪间充质干细胞类髓核分化的作用机制

Action mechanism of Bushenhuoxue decoction on promoting nucleus pulposus-like differentiation of adipose-derived stem cells

背景:干细胞移植是防治椎间盘退变的新思路,但移植后的干细胞如何顺利存活、增殖、分化,并恢复髓核细胞功能,是目前亟需克服的重点和难点。目的:探讨补肾活血方对脂肪间充质干细胞存活、增殖、类髓核分化的影响。方法:采用Transwell小室构建人脂肪间充质干细胞和人退变髓核细胞共培养模型。实验分为对照组、模型组、含药血清组、无药血清组,除对照组外,其余各组均用50μmol/L叔丁基过氧化氢干预24 h,然后含药血清组和无药血清组分别予以含体积分数20%补肾活血方含药血清或无药血清的DMEM低糖完全培养液干预48 h,取下层脂肪间充质干细胞,甲苯胺蓝染色法观察蛋白聚糖合成水平,Real-Time PCR法检测Ⅱ型胶原、蛋白聚糖、SOX9的mRNA表达,Western blot法检测SOX9的蛋白表达,乳酸脱氢酶法检测细胞毒性,流式细胞术检测细胞活性氧水平,β-半乳糖苷酶染色检测细胞衰老情况。结果与结论:①与对照组相比,模型组坏死脱落细胞比例增加,甲苯胺蓝染色变浅,Ⅱ型胶原、蛋白聚糖、SOX9 mRNA和SOX9蛋白表达水平下降(P<0.05);与模型组相比,补肾活血方含药血清可显著减轻细胞损伤并促进Ⅱ型胶原、蛋白聚糖、SOX9 mRNA和SOX9蛋白表达(P<0.05),但无药血清组改善不明显(P>0.05);②与对照组相比,模型组细胞毒性、活性氧水平、细胞衰老水平显著增加;与模型组相比,补肾活血方干预后共培养体系微环境得到明显改善(P<0.05),无药血清对共培养体系微环境改善作用不明显(P>0.05);③结果表明,补肾活血方可以促进脂肪间充质干细胞存活、增殖、类髓核分化。

BACKGROUND:Stem cell transplantation is a new way to prevent and cure intervertebral disc degeneration.However,whether the transplanted stem cells can survive,proliferate,differentiate,and restore the function of nucleus pulposus cells after transplantation,is the key and difficult point to overcome.OBJECTIVE:To explore the effects of Bushenhuoxue decoction on survival,proliferation,and nucleus pulposus-like differentiation of adipose-derived stem cells.METHODS:A Transwell chamber was used to construct a co-culture model of human adipose-derived stem cells and human degenerative nucleus pulposus cells.The experiment was divided into control group,model group,drug-containing serum group,and drug-free serum group.Except for the control group,the co-culture system of other groups was treated with 50μmol/L tert-butyl hydrogen peroxide for 24 hours.The drug-containing serum group and drug-free serum group were treated with DMEM low-glucose complete culture medium containing drug-containing serum of Bushenhuoxue decoction or drug-free serum with 20%volume fraction for 48 hours.The sublayer adipose-derived stem cells were taken.Toluidine blue staining was used to detect proteoglycan synthesis levels.Real-time PCR method was used to detect mRNA expression of type II collagen,proteoglycan and SRY-box transcription factor 9.The protein expression of SOX9 was detected by western blot assay.Lactate dehydrogenase assay was used to detect cytotoxicity.Flow cytometry was used to detect reactive oxygen species,andβ-galactosidase staining was used to detect cell senescence.RESULTS AND CONCLUSION:(1)Compared with the control group,the proportion of necrotic cells in the model group increased;toluidine blue staining became lighter,and the expression levels of type II collagen,proteoglycan,SOX9 mRNA and SOX9 protein decreased(P<0.05).Compared with the model group,the drug-containing serum of Bushenhuoxue decoction could significantly reduce cell injury and promote the expression of type II collagen,proteoglycan,SOX9 mRNA,and SOX9 protein(P<0.05),but the improvement in the drug-free serum group was not significant(P>0.05).(2)Compared with the control group,the contents of cytotoxicity,reactive oxygen species,and cell senescence in the model group were significantly increased.Compared with the model group,the microenvironment of the coculture system was significantly improved by drug-containing serum of Bushenhuoxue decoction(P<0.05),while drug-free serum had no significant effect on the microenvironment of the co-culture system(P>0.05).(3)The results show that Bushenhuoxue decoction can promote the survival,proliferation,and nucleus pulposus-like differentiation of adipose-derived stem cells.