A decade ago, only two hormones, parathyroid hormone and 1,25(OH)2D, were widely recognized to direct-ly affect phosphate homeostasis. Since the discovery of fibroblast growth factor 23 (FGF23) in 2000 (1), our ...A decade ago, only two hormones, parathyroid hormone and 1,25(OH)2D, were widely recognized to direct-ly affect phosphate homeostasis. Since the discovery of fibroblast growth factor 23 (FGF23) in 2000 (1), our understanding of the mechanisms of phosphate homeostasis and of bone mineralization has grown exponentially. FGF23 is the link between intestine, bone, and kidney together in phosphate regulation. However, we still do not know the complex mechanism of phosphate homeostasis and bone mineralization. The physiological role of FGF23 is to regulate serum phosphate. Secreted mainly by osteocytes and osteo- blasts in the skeleton (2-3), it modulates kidney handling of phosphate reabsorption and calcitriol produc-tion. Genetic and acquired abnormalities in FGF23 structure and metabolism cause conditions of either hyper-FGF23 or hypo-FGF23. Hyper-FGF23 is related to hypophosphatemia, while hypo-FGF23 is related to hyperphosphatemia. Both hyper-FGF23 and hypo-FGF23 are detrimentalto humans. In this review, we will discuss the vathovhvsiology of FGF23 and hvver-FGF23 related renal vhosvhate wasting disorders (4).展开更多
One of the major causes of congenital hypophosphatemic rickets is the X-linked hypophosphatemic rickets (XHR), due to a defect on PHEX gene. The XHR increases the renal elimination of phosphate, that condition leads a...One of the major causes of congenital hypophosphatemic rickets is the X-linked hypophosphatemic rickets (XHR), due to a defect on PHEX gene. The XHR increases the renal elimination of phosphate, that condition leads a defective mineralization of bones and also affects the growth in children. Clinical diagnosis should be suspected in children with signs of rickets and hypophosphatemia with normal calcium levels. We describe clinical characteristics and genetic results of four patients diagnosed and treated in our Nephrology Section. All patients have a “de novo” XHR as none familiars are affected. Early diagnosis should be suspected before the bone deformities have been submitted and the growth would have been impaired.展开更多
Bone was reported as a crucial organ for regulating glucose homeostasis. In this study, we found that Phex mutant mice(PUG), a model of human X-linked hypophosphatemic rickets(XLH), displayed metabolic abnormality in ...Bone was reported as a crucial organ for regulating glucose homeostasis. In this study, we found that Phex mutant mice(PUG), a model of human X-linked hypophosphatemic rickets(XLH), displayed metabolic abnormality in addition to abnormal phosphate homeostasis, skeletal deformity and growth retardation. Glucose tolerance was elevated with enhanced insulin sensitivity in PUG, though circulating insulin level decreased. Interestingly, bone mineral density defects and glucose metabolic abnormality were both rescued by adding phosphorus- and calcium-enriched supplements in daily diet. Serum insulin level, glucose tolerance and insulin sensitivity showed no differences between PUG and wild-type mice with rescued osteocalcin(OCN) following treatment. Our study suggested that OCN is a potential mediator between mineral homeostasis and glucose metabolism. This investigation brings a new perspective on glucose metabolism regulation through skeleton triggered mineral homeostasis and provides new clues in clinical therapeutics of potential metabolic disorders in XLH patients.展开更多
目的以一个临床表型为低血磷性佝偻病(hypophosphatemic rickets,HR)的家系为研究对象,通过全外显子组测序寻找该家系的致病变异基因,并分析变异的致病性。方法收集HR家系临床资料,进行生化检测。提取先证者DNA,进行临床全外显子组测序...目的以一个临床表型为低血磷性佝偻病(hypophosphatemic rickets,HR)的家系为研究对象,通过全外显子组测序寻找该家系的致病变异基因,并分析变异的致病性。方法收集HR家系临床资料,进行生化检测。提取先证者DNA,进行临床全外显子组测序,并针对可疑致病变异对家系所有成员进行PCR扩增,Sanger测序验证。预测变异的致病性及对蛋白质空间结构的影响。结果该家系共3代,先证者是一位26岁女性,先证者母亲、先证者及其儿子和女儿为患者,临床表现为O型腿、鸡胸、低磷血症,骨骼X线检查、生化检测、成纤维细胞生长因子23(fibroblast growth factor 23,FGF23)检测结果提示低血磷性佝偻病。临床全外显子组测序发现PHEX(NM_000444)c.2193dupT的插入移码杂合变异,该变异可导致编码第732位的天冬酰胺变异为终止密码子(p.N732*),从而出现了蛋白质截短。先证者的母亲、儿子及女儿PHEX基因均存在该变异。根据美国医学遗传学与基因组学学会(American College of Medical Genetics and Genomics,ACMG)对变异的分类标准,分级为可能致病性变异。经查阅文献及查找人类基因突变数据库,该变异均未被报道或收录。结论本研究发现了一个PHEX新致病变异,为该家系的临床诊断和治疗及遗传咨询提供了实验依据。展开更多
基金supported by the National Natural Science Foundation of China (No.81070687 and 8117-0805)National Science and Technology Major Projects for"Major New Drugs Innovation and Development"(Grant No.2008ZX09312-016)Beijing Natural Science Foundation(No.7121012)
文摘A decade ago, only two hormones, parathyroid hormone and 1,25(OH)2D, were widely recognized to direct-ly affect phosphate homeostasis. Since the discovery of fibroblast growth factor 23 (FGF23) in 2000 (1), our understanding of the mechanisms of phosphate homeostasis and of bone mineralization has grown exponentially. FGF23 is the link between intestine, bone, and kidney together in phosphate regulation. However, we still do not know the complex mechanism of phosphate homeostasis and bone mineralization. The physiological role of FGF23 is to regulate serum phosphate. Secreted mainly by osteocytes and osteo- blasts in the skeleton (2-3), it modulates kidney handling of phosphate reabsorption and calcitriol produc-tion. Genetic and acquired abnormalities in FGF23 structure and metabolism cause conditions of either hyper-FGF23 or hypo-FGF23. Hyper-FGF23 is related to hypophosphatemia, while hypo-FGF23 is related to hyperphosphatemia. Both hyper-FGF23 and hypo-FGF23 are detrimentalto humans. In this review, we will discuss the vathovhvsiology of FGF23 and hvver-FGF23 related renal vhosvhate wasting disorders (4).
文摘One of the major causes of congenital hypophosphatemic rickets is the X-linked hypophosphatemic rickets (XHR), due to a defect on PHEX gene. The XHR increases the renal elimination of phosphate, that condition leads a defective mineralization of bones and also affects the growth in children. Clinical diagnosis should be suspected in children with signs of rickets and hypophosphatemia with normal calcium levels. We describe clinical characteristics and genetic results of four patients diagnosed and treated in our Nephrology Section. All patients have a “de novo” XHR as none familiars are affected. Early diagnosis should be suspected before the bone deformities have been submitted and the growth would have been impaired.
基金supported by National Key Technology Support Program(2011BAI15B02,2012BAI39B01)National Key Basic Research Program of China(2011CB944104)
文摘Bone was reported as a crucial organ for regulating glucose homeostasis. In this study, we found that Phex mutant mice(PUG), a model of human X-linked hypophosphatemic rickets(XLH), displayed metabolic abnormality in addition to abnormal phosphate homeostasis, skeletal deformity and growth retardation. Glucose tolerance was elevated with enhanced insulin sensitivity in PUG, though circulating insulin level decreased. Interestingly, bone mineral density defects and glucose metabolic abnormality were both rescued by adding phosphorus- and calcium-enriched supplements in daily diet. Serum insulin level, glucose tolerance and insulin sensitivity showed no differences between PUG and wild-type mice with rescued osteocalcin(OCN) following treatment. Our study suggested that OCN is a potential mediator between mineral homeostasis and glucose metabolism. This investigation brings a new perspective on glucose metabolism regulation through skeleton triggered mineral homeostasis and provides new clues in clinical therapeutics of potential metabolic disorders in XLH patients.
文摘目的以一个临床表型为低血磷性佝偻病(hypophosphatemic rickets,HR)的家系为研究对象,通过全外显子组测序寻找该家系的致病变异基因,并分析变异的致病性。方法收集HR家系临床资料,进行生化检测。提取先证者DNA,进行临床全外显子组测序,并针对可疑致病变异对家系所有成员进行PCR扩增,Sanger测序验证。预测变异的致病性及对蛋白质空间结构的影响。结果该家系共3代,先证者是一位26岁女性,先证者母亲、先证者及其儿子和女儿为患者,临床表现为O型腿、鸡胸、低磷血症,骨骼X线检查、生化检测、成纤维细胞生长因子23(fibroblast growth factor 23,FGF23)检测结果提示低血磷性佝偻病。临床全外显子组测序发现PHEX(NM_000444)c.2193dupT的插入移码杂合变异,该变异可导致编码第732位的天冬酰胺变异为终止密码子(p.N732*),从而出现了蛋白质截短。先证者的母亲、儿子及女儿PHEX基因均存在该变异。根据美国医学遗传学与基因组学学会(American College of Medical Genetics and Genomics,ACMG)对变异的分类标准,分级为可能致病性变异。经查阅文献及查找人类基因突变数据库,该变异均未被报道或收录。结论本研究发现了一个PHEX新致病变异,为该家系的临床诊断和治疗及遗传咨询提供了实验依据。