Simultaneous quantification of cefuroxime and clindamycin in human lumbar anulus fibrosus, nucleus pulposus and serum via UPLC-MS/MS.

BACKGROUND: This study aimed to develop a sensitive, accurate method for simultaneously quantifying cefuroxime and clindamycin in human serum, lumbar anulus fibrosus and nucleus pulposus. METHODS: Cefuroxime and clindamycin were quantified using ultra high-performance liquid chromatography-electrospray ionization tandem mass spectrometry in multiple-reaction-monitoring mode on a triple-quadrupole AB Qtrap 5500 system in positive ion mode. Internal standards were D3-cefuroxime and D3,13C-clindamycin. Samples were pretreated by precipitating total protein. RESULTS: The method showed high sensitivity and good linearity over broad calibration ranges from 100 to 100 000 ng/mL for cefuroxime and 10 to 10 000 ng/mL for clindamycin in serum, and from 10 to 10 000 ng/mL for cefuroxime and 1 to 1 000 ng/mL for clindamycin in lumbar nucleus pulposus. In all sample types, correlation coefficients were greater than 0.99, intra- and inter-day precision (relative standard deviation) was less than 15%, and accuracy (relative error) was within 14% for both analytes. This method was effective at quantifying penetration of cefuroxime and clindamycin in patients undergoing oblique lumbar interbody fusion surgery. CONCLUSIONS: A very sensitive, specific method for simultaneous detection of cefuroxime and clindamycin has been developed for human lumbar anulus fibrosus, nucleus pulposus and serum samples.

Ginsenoside Rg1 promotes growth and extracellular matrix synthesis in degenerative human lumbar nucleus pulposus cells by inhibiting Wnt/β-catenin pathway / 中国病理生理杂志

AIM:To explore the role of ginsenoside Rg1 in the growth of degenerative human lumbar nucleus pulposus cells(HNPCs).METHODS:Cultured HNPCs were subjected to oxygen-glucose deprivation(OGD)to mimic the micro-environment of degenerative HNPCs.The morphological changes of the cells in control group and OGD group were observed under optical microscope.The cells were treated with ginsenoside Rg 1 at concentrations of 25,50 and 100 μmol/L.The expression of collagen II and aggrecan at mRNA and protein levels was determined by real -time PCR and Western blot analysis.The cell viability was measured by CCK-8 assay.The mRNA level of Ki67 was detected by real-time PCR.The apoptosis was analyzed by flow cytometry.The activity of caspase-3 was measured by a caspase-3 kit.The ex-pression of Wnt/β-catenin pathway-related proteins was determined by Western blot.Furthermore,the expression of Wnt/β-catenin pathway-related proteins,the cell viability and apoptosis,and the expression of extracellular matrix synthesis pro-teins were assessed after the cells were co-treated with LiCl and 100 μmol/L ginsenoside Rg1.RESULTS:Normal HNPCs attached on the cell culture plate faster, and were almost round with rich cytoplasm.However, the cell adherence was slower,and the cells were long fusiform with decreased cytoplasm after OGD treatment,indicating that the model of degen-erative HNPCs was successfully established.Compared with normal HNPCs,the expression of collagen II and aggrecan at mRNA and protein levels was decreased in OGD group(P<0.05),which was then increased after the cells were treated with ginsenoside Rg1 at 25,50 and 100 μmol/L(P<0.05).Compared with normal HNPCs,the cell viability and Ki67 expression were decreased in OGD group(P<0.05), which were increased after treatment with ginsenoside Rg 1(P<0.05).Meanwhile,the apoptotic rate and caspase-3 activity were significantly increased in OGD-treated cells(P<0.05), which were decreased after treatment with ginsenoside Rg 1(P<0.05).In addition,the activation of Wnt/β-catenin path-way was also inhibited by ginsenoside Rg 1 treatment at dose of 100 μmol/L(P<0.05).LiCl,a Wnt/β-catenin pathway agonist,obviously decreased the protective effects of ginenoside Rg 1 on OGD-induced cells(P<0.05),indicating that the Wnt/β-catenin pathway was involved in the protective effects of ginenoside Rg 1 on degenerative HNPCs.CONCLUSION:Ginsenoside Rg1 promotes growth and extracellular matrix synthesis of degenerative HNPCs through inhibiting Wnt /β-cate-nin pathway.This study will provide a new idea for prevention and treatment of degenerative HNPCs.