AIM: To investigate the possible involvement of 25-hydroxyvitamin D3-1cx-hydroxylase [1α-25(OH)2D3] in butyrate-induced differentiation in human intestinal cell line Caco-2 cells. METHODS: Caco-2 cells were incub...AIM: To investigate the possible involvement of 25-hydroxyvitamin D3-1cx-hydroxylase [1α-25(OH)2D3] in butyrate-induced differentiation in human intestinal cell line Caco-2 cells. METHODS: Caco-2 cells were incubated either with 3 mmol/L butyrate and 1 umol/L 25(OH)2D3 or with 1 umol/L 1α-25(OH)2D3 for various time intervals ranging from 0 to 72 h. Additionally, cells were co-incubated with butyrate and either 25(OH)2D3 or 1α-25(OH)2D3. 1α-25(OH)2D3 mRNA was determined semi-quantitatively using the fluorescent dye PicoGreen. Immunoblotting was used for the detection of 1α-25(OH)2D3 protein. Finally, enzymatic activity was measured by ELISA. RESULTS: Both butyrate and 1α-25(OH)2D3 stimulated differentiation of Caco-2 cells after a 48 h incubation period, while 25(OH)2D3 had no impact on cell differentiation. Synergistic effects on differentiation were observed when cells were co-incubated with butyrate and vitamin D metabolite. Butyrate transiently upregulated 1α-25(OH)2D3 mRNA followed by a timely delayed protein upregulation. Coincidently, enzymatic activity was enhanced significantly. The induction of the enzyme allowed for comparable differentiating effects of both vitamin D metabolites. CONCLUSION: Our experimental data provide a further mechanism for the involvement of the vitamin D signaling pathway in colonic epithelial cell differentiation by butyrate. The enhancement of 1α-25(OH)2D3 followed by antiproliferative effects of the vitamin D prohormone in the Caco-2 cell line suggest that 25(OH)2D3 in combination with butyrate may offer a new therapeutic approach forthe treatment of colon cancer.展开更多
目的探讨帕金森病(parkinson's disease,PD)患者髋部骨密度(bone mineral density,BMD)、25-羟维生素D3与髋部骨折的相关性。方法以61例年龄在51~68岁的帕金森病患者为PD组,以64名年龄和性别匹配的健康人群作为对照组,采用双能X射...目的探讨帕金森病(parkinson's disease,PD)患者髋部骨密度(bone mineral density,BMD)、25-羟维生素D3与髋部骨折的相关性。方法以61例年龄在51~68岁的帕金森病患者为PD组,以64名年龄和性别匹配的健康人群作为对照组,采用双能X射线骨密度仪测定骨密度,采用电化学发光法检测25-羟维生素D3水平。对两组受试者跟踪随访3年,记录随访期间髋部骨折的发生情况并进行对比。结果 PD组髋部总骨密度、股骨颈骨密度、转子间骨密度、股骨干骨密度均低于对照组,差异具有统计学意义(t值分别为-3.747、-4.256、-4.706、-4.274,P均<0.001)。PD组25-羟维生素D3水平明显低于对照组,差异具有统计学意义(t=-4.500,P<0.001)。PD组中髋部总骨密度与25-羟维生素D3具有相关性(r=0.510,P=0.047)。PD组髋部骨折发生率高于对照组,差异有统计学意义(χ~2=4.04,P=0.04)。结论 PD患者髋部骨折发生率较同年龄、同性别健康人群高,髋部骨折发生与髋部骨密度和25-羟维生素D3水平有关。展开更多
基金Supported by the Else Kroner-Fresenius Foundation, Bad Homburg, Germany
文摘AIM: To investigate the possible involvement of 25-hydroxyvitamin D3-1cx-hydroxylase [1α-25(OH)2D3] in butyrate-induced differentiation in human intestinal cell line Caco-2 cells. METHODS: Caco-2 cells were incubated either with 3 mmol/L butyrate and 1 umol/L 25(OH)2D3 or with 1 umol/L 1α-25(OH)2D3 for various time intervals ranging from 0 to 72 h. Additionally, cells were co-incubated with butyrate and either 25(OH)2D3 or 1α-25(OH)2D3. 1α-25(OH)2D3 mRNA was determined semi-quantitatively using the fluorescent dye PicoGreen. Immunoblotting was used for the detection of 1α-25(OH)2D3 protein. Finally, enzymatic activity was measured by ELISA. RESULTS: Both butyrate and 1α-25(OH)2D3 stimulated differentiation of Caco-2 cells after a 48 h incubation period, while 25(OH)2D3 had no impact on cell differentiation. Synergistic effects on differentiation were observed when cells were co-incubated with butyrate and vitamin D metabolite. Butyrate transiently upregulated 1α-25(OH)2D3 mRNA followed by a timely delayed protein upregulation. Coincidently, enzymatic activity was enhanced significantly. The induction of the enzyme allowed for comparable differentiating effects of both vitamin D metabolites. CONCLUSION: Our experimental data provide a further mechanism for the involvement of the vitamin D signaling pathway in colonic epithelial cell differentiation by butyrate. The enhancement of 1α-25(OH)2D3 followed by antiproliferative effects of the vitamin D prohormone in the Caco-2 cell line suggest that 25(OH)2D3 in combination with butyrate may offer a new therapeutic approach forthe treatment of colon cancer.