1,25-(OH)2D3对局灶节段性肾小球硬化大鼠尿足细胞排泄及肾小球WT-1分布的影响

目的 探讨1,25-(OH)2D3对局灶节段性肾小球硬化(FSGS)大鼠尿足细胞(UPC)排泄及肾小球WT-1蛋白分布的影响.方法 24只SD大鼠分为3组:对照组、FSGS组、1,25-(OH)2D3组.采用左肾摘除,阿霉素重复注射诱导FSGS大鼠模型.1,25-(OH)2D3组在第1次给予阿霉素后1周埋植渗透性微量泵按0.03 ng/(g·d)皮下给予1,25-(OH)2D3.实验10周末检测尿白蛋白排泄率(UAER)、尿转化生长因子-β1(TGF-β1)及结缔组织生长因子(CTGF).免疫荧光法检测尿沉渣足细胞特异性标志蛋白Wflm's tumor-1(WT-1),观察肾小球WT-1的分布.尿WT-1荧光细胞即为尿液足细胞.结果 FSGS组UPC、UAER、TGF-β1、CTGF、肾小球细胞数及细胞外基质(ECM)/肾小球毛细血管襻面积均较对照组明显升高(P<0.01).与FSGS组相比,1,25-(OH)2D3组UAER、ECM/肾小球毛细血管襻面积显著降低(P<0.01),UPC、TGF-β1、肾小球细胞数亦降低(P<0.05),CTGF无统计学意义(P>0.05).肾小球荧光染色示WT-1在对照组正常,FSGS组呈节段性缺失,1,25-(OH)2D3组缺失较轻.UPC与UAER呈正相关(r.=0.42,P<0.05),TGF-β1与CTGF亦呈正相关(r.=0.47,P<0.05).结论 尿液中脱落足细胞检测可作为判断.FSGS病情活动性的标志之一.1,25-(OH)2D3可减轻FSGS大鼠UPC、UAER、TGF-β1的排泄,抑制肾小球细胞数及ECM增殖,恢复肾组织WT1-表达而有肾保护作用.     

1,25-二羟维生素D3在慢性肾疾病中的作用

1,25-二羟维生素D3[1,25-(OH)2D3]是维生素D的活性代谢产物,除有促进钙磷吸收及免疫调节作用外,还能负向调节肾素-血管紧张素系统的活性,减少肾小球硬化,抑制转化生长因子-β1诱导肾小管上皮细胞向间质细胞转化,减轻肾小管间质纤维化;而且参与滤过屏障的维持,恢复裂孔隔膜蛋白的表达,减少足细胞的损伤脱落,降低慢性肾疾病蛋白尿.其肾保护作用为临床治疗慢性肾疾病提供了可供选择的药物之一.该文综述1,25-(OH)2D3在慢性肾疾病中的积极作用.     

1,25-(OH)2D3对糖尿病大鼠肾脏Nephrin蛋白表达的影响

目的探讨1,25-(OH)2D3对糖尿病(DM)大鼠肾脏Nephrin蛋白表达的影响。方法Wistar大鼠分为对照组、DM组、1,25-(OH)2D3组。建立糖尿病大鼠模型,实验12周末观察各组血尿、蛋白尿、肾组织光镜电镜、免疫组织化学,采用反转录聚合酶链反应(RT-PCR)检测其肾皮质NephrinmRNA及蛋白的表达。结果与对照组及1,25-(OH)2D3组相比,DM组大鼠尿红细胞及尿蛋白排泄明显增多,肾小球细胞数亦增加(P<0.01,0.05),NephrinmRNA及蛋白质表达明显下调(Pa<0.01)。1,25-(OH)2D3组肾小球细胞数、NephrinmRNA及蛋白质表达与对照组相比无统计学差异(Pa>0.05)。结论1,25-(OH)2D3可减轻血尿、蛋白尿,上调NephrinmRNA及蛋白质的表达而有肾保护作用。     

1,25(OH)2D3对载脂蛋白E缺乏鼠主动脉内皮细胞增生与凋亡及一氧化氮合酶表达的影响

目的 了解1,25(OH)2D3对载脂蛋白E缺乏鼠(apoE-/-)主动脉内皮细胞(EC)增生、凋亡及内皮型一氧化氮合酶(eNOS)表达的影响.方法 apoE-/-鼠主动脉EC分离培养,MTT法观察1,25(OH)2D3影响apoE-/-鼠EC生长,TUNEL检测细胞凋亡,RT-PCR检测Bc1-2、Fas mRNA和eNOS mRNA表达.结果 细胞对照组与无水乙醇对照组EC增生率差异无统计学意义[(0.162±0.031)vs.(0.158±0.006),p＞0.05],1,25(OH)2D3在10-4、10-5、10-6、10-7、10-8 mol/L时EC增生率高于对照组(P＜0.01),但不同浓度1,25( OH)2D3作用组之间差异无统计学意义[分别为(0.189±0.013)、(0.285±0.011)、(0.296±0.026)、(0.284±0.017)、(0.233±0.010),P ＞0.05],选定10-6mol/L 1,25(OH)2D3为研究浓度,干预分离培养apoE-/-鼠主动脉EC.1,25( OH)2D310-6mol/L组、细胞对照组、无水乙醇对照组凋亡指数分别为(15.14±3.19)、(18.94 ±4.22)、(19.27±4.58),Bcl-2 mRNA分别为(0.78±0.16)、(0.46±0.21)、(0.42±0.17),Fas mRNA分别为(0.43±0.12)、(0.79±0.21)、(0.81±0.20),eNOS mRNA分别为(0.56±0.16)、(0.39±0.13)、(0.35±0.11).25(OH)2D3干预组EC凋亡指数、Fas mRNA、eNOS mRNA降低,Bcl-2 mRNA增高(P均＜0.01),细胞对照组与无水乙醇对照组比较差异无统计学意义(P＞0.05).相关分析发现在1,25(OH)2D3干预组,eNOS表达量与凋亡指数、Fas mRNA呈负相关(r=-0.676、-0.758),与Bcl-2表达呈正相关(r =0.762),差异有统计学意义(P均＜0.01).结论 1,25(OH)2D3刺激apoE-/-鼠主动脉EC增生、抑制主动脉EC凋亡,影响凋亡相关基因Bcl-2、Fas mRNA表达,上调eNOS mRNA表达.     

孕期和哺乳期1，25-（OH）2D3干预对子代哮喘大鼠肺组织TGF-β1和Smad3表达的影响

目的：探讨孕期和哺乳期1,25-二羟维生素D3［1,25-（OH）2D3］干预对子代哮喘大鼠肺组织中转化生长因子β1（TGF-β1）及Smad3表达的影响。方法：雌性Wistar大鼠32只,随机分为4组（n=8）：低剂量、中剂量及高剂量1,25-（OH）2D3干预组和对照组。受孕第7天起,以隔天灌胃的方式分别给予低、中剂量及高剂量组2、10、20 μg/mL 1,25-（OH）2D3,对照组以生理盐水代替,直到子代大鼠生后21 d断乳为止。制备子代大鼠哮喘模型。采用RT-PCR和免疫组织化学方法分别从mRNA和蛋白水平检测TGF-β1和Smad3的表达变化。结果：(1)各组仔鼠哮喘模型支气管炎症程度不同,与对照组相比,低、中剂量组炎症反应减轻,而高剂量组则加重。(2)免疫组织化学结果显示,与对照组相比,TGF-β1及pSmad3在低、中剂量组表达明显降低（P<0.05）,而在高剂量组则表达明显增高（P<0.05）。(3) 荧光定量PCR结果显示,与对照组相比,低、中剂量组TGF-β1和Smad3 mRNA表达降低（P<0.05）,而高剂量组两者的mRNA表达增高（P<0.05）。结论：在大鼠哮喘模型中,1,25-（OH）2D3可能通过维生素D受体信号通路,进而调节TGF-β/Smad信号通路相关蛋白的表达而发挥免疫调节作用。     

1,25-(OH)2D3抑制脂多糖诱导的脐血CD4+T细胞IL-13和IL-17的表达

目的 本研究旨在探讨生命早期脂多糖(LPS)对脐血CD4+T细胞白介素-13(IL-13)和白介素-17(IL-17)表达的影响及1,25-(OH)2D3对其表达的干预作用,为维生素D的临床合理应用及其对哮喘等变态反应性疾病的防治提供理论依据。方法 选取顺产的足月新生儿12例,断脐后立即取胎盘端脐静脉血50 mL,采用密度梯度离心法分离脐血单个核细胞(CBMCs),磁珠分选CD4+T细胞后依据不同的处理方法分为空白刺激组、LPS(10 μg/mL)单独刺激组和LPS(10 μg/mL)+1,25-(OH)2D3(10-8 mmol/L)共刺激组。培养72 h后采用双抗夹心酶联免疫吸附试验(ELISA)和Real-Time PCR分别检测培养上清液中IL-13和IL-17水平及CD4+T细胞中IL-13和IL-17 mRNA表达。结果 与空白刺激组相比,LPS单独刺激组培养上清液中IL-13和IL-17水平及CD4+T细胞中IL-13和IL-17 mRNA表达水平明显升高(均P<0.01),而1,25-(OH)2D3处理可降低其表达水平(均P<0.05),但仍高于空白刺激组(均P<0.01)。结论 LPS可促进脐血CD4+T细胞IL-13和IL-17的表达;1,25-(OH)2D3对于LPS诱导的脐血CD4+T细胞IL-13和IL-17表达具有抑制作用,提示1,25-(OH)2D3可能在变应原致敏的早期发挥一定保护作用。     

活性维生素D调节尿毒症大鼠骨形态发生蛋白-7和转化生长因子-β1的表达

目的 观察骨形态发生蛋白-7(BMP-7)、转化生长因子-β1(TGF-β1)在尿毒症大鼠肾小球中的表达及活性维生素D对二者表达的影响,探讨维生素D的肾保护作用及机制.方法 切除大鼠右肾并结扎左肾动脉前支诱导尿毒症大鼠模型,将尿毒症大鼠分为尿毒症组(UC组)和尿毒症 + 1,25(OH)2D3组(UD组).正常大鼠为正常对照组(NC组).实验第8周,检测大鼠收缩压(SBP),24 h尿蛋白(24 h UP)、尿足细胞(UPC),血清钙、磷、25(OH)D3、成纤维细胞生长因子23(FGF23)水平.反转录(RT)-PCR检测其肾小球BMP-7、TGF-β1 mRNA的表达,蛋白印迹法检测其肾小球BMP-7、TGF-β1蛋白表达.结果 UC组和UD组SBP比较无统计学差异,且均高于NC组.与NC组比较,UC组血清磷、FGF23、24 h UP、UPC显著升高,钙、25(OH)D3降低.与UC组比较,UD组血清磷、FGF23、24 h UP、UPC显著降低,血清钙、25(OH)D3升高.与NC组比较,UC组BMP-7 mRNA及蛋白质的表达明显下调、TGF-β1 mRNA及蛋白质表达明显上调.与UC组比较,UD组BMP-7 mRNA及蛋白质表达分别增加14.8%、31.1%,TGF-β1 mRNA及蛋白质表达分别减少35.7%、43.9%.结论 1,25(OH)2D3不仅可改善尿毒症大鼠钙磷代谢,并可增加BMP-7表达,减少TGF-β1表达,减轻蛋白尿及UPC的排泄.     

降钙素能使初生婴儿血清1,25-(OH)_2D增高

1,25-(OH),D是VitD活性最强的代谢产物,主要由于25OHD通过甲状旁腺(PTH)-cAMP在肾近曲管激活1,25-OHD-1α羟化酶合成;另一条途径是降钙素(CT)在肾近端直管合成1,25-(OH)_2D。材料和结果 1984年12月～1985年2月对28名健康母亲及其足月顺产儿第1天(脐血)、第5天检查血Ca、P、总蛋白/PTH、尿cAMP肌酐、肾源性cAMP、CT、25-(OH)D及1,25-(OH)_2 D,将其结果与成人进行对照。 1.25-(OH)D与1,25-(OH)_2D:母血25-(OH)D(16.3±6.2ng/ml)明显高于脐血(7.6±4.6ng/ml)和5天婴儿(9.7±3.4ng/ml)的水平三者间用回归线方法,最终的相关系数(r)呈显著性相关。     

1,25-(OH)2D3对哮喘小鼠肺内TIM-4表达的影响

目的：建立小鼠哮喘气道重塑模型,观察1,25-(OH)2D3对哮喘小鼠气道结构及T细胞免疫球蛋白域粘蛋白域蛋白-4（T cell immunoglobulin mucin protein-4, TIM-4）表达的影响。方法：30只BALB/c雌性小鼠随机分为对照组、哮喘组和1,25-(OH)2D3干预组,采用卵清蛋白致敏、激发建立哮喘模型。取小鼠肺组织,采用苏木精-伊红染色观察气道重塑情况,并应用RT-PCR法和免疫组化法检测肺内TIM-4 mRNA和蛋白的表达。结果：哮喘组发生典型的气道重塑改变,与对照组比较,TIM-4表达水平升高（105±9 vs 42±5,P<0.05）;1,25-(OH)2D3干预组较哮喘组气道重塑有所改善,TIM-4表达降低（78±6）,差异有统计学意义（P<0.05）。结论：TIM-4可能参与小鼠气道重塑过程;新型免疫调节剂1,25-(OH)2D3可下调哮喘小鼠肺内TIM 4的表达,改善气道重塑。     

Vitamin D: the discovery of its metabolites and their therapeutic applications.

Our understanding of the role of vitamin D in calcium-phosphorus metabolism has changed considerably in the last decade. Studies performed in tissue culture, animal, and man have firmly established that the natural compound requires hydroxylation in the liver at the C-25 position and in the kidney at the C-1 position to form the biologically active derivative 1,25-(OH)2D3. These hydroxylation reactions are finely regulated to maintain normal calcium-phosphorus homeostasis: We now regard 1,25-(OH)2D3 as a hormone which is released by the kidney during periods of hypocalcemia. This hormone acts on the intestinal mucosa to facilitate calcium absorption and on bone to increase calcium mobilization. Its function in other tissues is still being evaluated. The active metabolites of vitamin D and several closely related analogs have been synthesized. It has been clearly demonstrated that 1,25-(OH)2D3 and 1alpha-OH-D3 promote healing in uremic bone disease. Administration of small amounts of these compounds has corrected the biochemical disturbances in vitamin D-dependency and hypoparathyroidism. Limited clinical experience with 25-OH-D3 and 1,25-(OH)2D3 in children with familial hypophosphatemia has failed to show convincing evidence of a therapeutic effect. Further clinical studies are needed to fully evaluate the therapeutic potential of this new family of compounds.     

Lung as a possible additional target organ for vitamin D during fetal life in the rat

The presence of specific cytosol binding sites for 1,25-(OH)2D3 was evaluated in rat fetal tissues during the last quarter of gestation (days 17-21). The content of 1,25-(OH)2D3-binding sites was low in intestine, brain, liver, spleen, pancreas, sternum and thymus during the period of gestation studied. It was highest in skeleton (ribs and vertebral bodies), kidney and lung from day 19 onwards. In the cytosol of these latter tissues, a high affinity (Kd 0.7-3.6 X 10(-10) M, low capacity [3H]1,25-(OH)2D3 binding was demonstrated and a distinct 2.9- to 3.5-S [3H]1,25-(OH)2D3-binding component was observed. These findings suggest that fetal lung, skeleton and kidney are possibly major target tissues for 1,25-(OH)2D3.     

Vitamin D metabolism in biliary atresia: intestinal absorptions of 25-hydroxyvitamin D3 and 1,25-dihydroxyvitamin D3

In children with biliary atresia, defective intestinal absorption of vitamin D and impaired hepatic uptake and 25-hydroxylation of vitamin D lead to a deficiency of vitamin D and rickets. We recently observed severe rickets in a 3-year-old boy with corrected biliary atresia resulting in jaundice, despite oral treatment with 1 alpha-hydroxyvitamin D3 (1 alpha-OHD3) or 1,25-dihydroxyvitamin D3 [1,25-(OH)2D3]. He had low 25-hydroxyvitamin D (25-OHD) and high 1,25-(OH)2D serum levels. Intramuscular vitamin D2 administration produced radiological and biochemical evidence of recovery. Oral 1,25-(OH)2D3 (0.1 microgram/kg) and 25-OHD3 (10 micrograms/kg) tolerance tests were done to assess the ability to absorb vitamin D and the effectiveness of using these drugs orally. Eleven children with corrected biliary atresia, aged 9 months to 7 years, were studied. In oral 1,25-(OH)2D3 tolerance tests, the increments above the baseline serum levels of 1,25-(OH)2D were 140.7 +/- 27.4 pg/ml in nonjaundiced patients (n = 5). In jaundiced patients (n = 3), 1,25-(OH)2D3 absorption in two patients with high basal 1,25-(OH)2D values was lower than that of nonjaundiced patients; however, the absorption in the third patient with a low basal value was similar to that of nonjaundiced patients. In oral 25-OHD3 tolerance tests, the mean increase of serum 25-OHD was 48.9 +/- 30.6 ng/ml in nonjaundiced patients (n = 5) and 23.7 +/- 9.5 ng/ml in jaundiced patients (n = 4), the peak serum 25-OHD levels being reached 6-12 h after 25-OHD3 loading.(ABSTRACT TRUNCATED AT 250 WORDS)     

1,25-Dihydroxyvitamin D3 in childhood hepatic osteodystrophy.

Osteodystrophy frequently accompanies severe childhood hepatobiliary disease. Proposed causes include malabsorption of vitamin D and calcium, and diminished 25-hydroxylation of vitamin D. Two children, ages 23 and 35 months, with radiographic and biochemical evidence of rickets with extrahepatic biliary atresia, were treated with 1,25-dihydroxyvitamin D3. The minimal effective therapeutic dose and efficacy of 1,25-(OH)2D3 in the treatment of rickets associated with severe childhood hepatic disease were determined. Oral 1,25-(OH)2D3 was ineffective at doses of 0.10 microgram/kg/day. Parenteral doses of 0.20 microgram/kg/day effectively produced radiographic, bone mineral (photon absorptiometric), and biochemical evidence of healing. The need for four times the physiologic dose of 1,25-(OH)2D3 by the parenteral route suggested enhanced catabolism of, or end-organ resistance to, 1,25-(OH)2D3 in our patients with severe cholestatic liver disease treated with phenobarbital.     

鼠尾草酸增加1,25(OH)2D3诱导HL-60细胞分化及其机制研究

目的：已证实1, 25(OH)2D3可以诱导HL-60细胞向成熟单核细胞分化,但其不足之处是高钙血症和形成耐药株。该实验应用鼠尾草酸（CA）联合1, 25(OH)2D3研究对HL-60细胞分化的影响及引起细胞内活性氧（ROS）水平和细胞内钙离子浓度的改变。方法：应用鼠尾草酸,1,25（OH）2D3单独和联合应用处理HL-60细胞,共分为5组：空白对照组;低浓度1,25（OH）2D3（1 nmol/L）组、鼠尾草酸组;联合处理组（10 μmol/L鼠尾草酸和1 nmol/L 1,25（OH）2D3）;高浓度1,25（OH）2D3（100 nmol/L）组。每24 h监测1次,通过四唑氮蓝(MTT)法观察细胞生长,共72 h;收集处理后72 h的HL-60细胞,通过光学显微镜观察细胞形态,用流式细胞仪（FCM）检测不同处理组细胞周期及单核细胞分化标记CD14的表达,ROS和细胞内钙离子浓度。结果：72 h后,联合处理组HL-60细胞与空白对照组相比,细胞增殖明显受抑制（Ab= 0.560±0.020; P<0.01）,细胞形态具有成熟单核细胞特征,CD14的表达率升高（57.62%;P<0.01）,G0/G1 期细胞显著增多, ROS水平下降［（52.67±10.76）%,P＜0.01］;联合处理组细胞内钙离子水平同空白对照组比较差异无显著性（115.64±17.74 nmol/L,P>0.05）,但与高浓度1,25（OH）2D3组相比细胞内钙离子水平明显下降(P<0.01)。结论：鼠尾草酸可增强1,25（OH）2D3对HL-60细胞的诱导分化、增强抑制HL-60细胞增殖作用,细胞阻滞于G0/G1期,细胞内活性氧水平降低,这可能与细胞的诱导分化机制有关,且这一联合作用不增高细胞内钙离子水平。     

Genetic causes of rickets.

Dietary deficiency of vitamin D, genetic disorders of its bioactivation to 1,25-dihydroxyvitamin D [1,25(OH)2D], or disorders of vitamin D action can cause rickets. The rate-limiting, hormonally-regulated, biologically activating step in the synthesis of 1,25(OH)2D is the 1 alpha-hydroxylation of 25-hydroxyvitamin D, which occurs in kidney and other tissues and is mediated by a mitochondrial cytochrome P450 enzyme, P450c1 alpha. After many years of effort, the cDNA and gene for this enzyme were cloned in late 1997. Mutations in the P450c1 alpha gene, located on chromosome 12, cause 1 alpha-hydroxylase deficiency, also known as vitamin D-dependent rickets type I, an autosomal recessive disease characterized by rickets and impaired growth due to failure of renal synthesis of 1,25(OH)2D. X-linked hypophosphatemic rickets, a dominantly inherited disease, is caused by mutations in the PHEX gene, whose function in regulating renal phosphate and vitamin D metabolism remains to be elucidated.     

1,25-dihydroxycholecalciferol in renal osteodystrophy. Epiphysiolysis--anticonvulsant therapy

Three children with azotaemic renal osteodystrophy were treated with 1,25-dihydroxycholecalciferol (1,25(OH)2D3). All showed clinical, biochemical, and radiological improvement within 6 months of starting treatment. There were no complications. The dose of 1,25(OH)2D3 required was 0-5 microgram per day for 2 children aged 22 and 30 months, and 2 microgram per day for a 15-year-old boy. 2 of the patients were receiving phenobarbitone and phenytoin and in one of them prior treatment with dihydrotachysterol 0-5 mg daily and 6 microgram 1alpha-hydroxycholecalciferol (1alphaOHD3) daily had failed to induce improvement. In one patient, in whom serial iliac bone samples were available, 2 microgram 1,25(OH)2D3 resulted in histological improvement in previously severe osteomalacia. 1,25(OH)2D3 appears to be an effective and safe drug in the treatment of uraemic osteodystrophy.