Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0018099 (gout)
 5,192 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Gout, which is commonly associated with hyperuricemia, affects 0.2% of the population. Hyperuricemia has a heterogeneous etiology that may be due to either over production and/or reduced renal clearance, of urate. In order to identify the mechanisms underlying reduced excretion of urate, we undertook positional cloning studies of familial juvenile hyperuricaemic nephropathy (FJHN), which is an autosomal dominant disorder characterized by hyperuricaemia, a low fractional renal excretion of urate, and chronic renal failure that is associated with interstitial fibrosis. The FJHN locus has been previously localized to a 22 centiMorgan interval flanked centromerically by D16S401 and telomerically by D16S3069, on chromosome 16p11-p13. This interval contains over 120 genes and we selected 13 renal expressed sequences to search for mutations in 5 unrelated FJHN families that contained 21 affected and 24 unaffected members. This revealed 5 heterozygous missense mutations (Cys77Tyr, Cys126Arg, Asn128Ser, Cys255Tyr and Cys300Gly) that altered evolutionary conserved residues in the gene encoding UROMODULIN. UROMODULIN, which is an 85 Kda glycoprotein, has roles in renal stone formation, the modulation of immune responses, and urothelial cytoprotection. The results of our studies, which have identified the gene causing FJHN, now indicate a further, novel role for UROMODULIN in urate metabolism.
 ...
PMID:UROMODULIN mutations cause familial juvenile hyperuricemic nephropathy. 1262 36

Medullary cystic kidney disease (MCKD) belongs with nephronophthisis (NPH) in a group of inherited tubulo-interstitial nephritis, which has been referred to as the NPH-MCKD complex. Although MCKD and NPH share morphological features, they differ in several respects. The most common variant is recessive juvenile NPH, with onset in childhood and leading to end-stage renal disease (ESRD) within the 2nd decade of life; the most frequent extrarenal involvement is tapeto-retinal degeneration. MCKD is a dominant condition recognized in later life and leading to ESRD at the age of 50 years; hyperuricemia and gout can be associated features. The first sign of MCKD is polyuria; later, the clinical findings relate to renal insufficiency. Originally, NPH and MCKD were considered separate entities. Subsequently, it has been suggested that the two diseases were a single disorder due to the clinico-pathological identity. This unifying conception was later refuted due to the identification of MCKD dominant families. Recently, considerable insight has been gained into the genetics of the NPH-MCKD complex. The majority of juvenile NPH cases are due to deletion of the NPHP1 gene on chromosome 2q13. Genes for infantile and adolescent NPH have been localized respectively to chromosome 9q22-q31 and 3q22. A new locus, NPHP4, has been recently identified on chromosome 1p36. Two genes predisposing to dominant MCKD, MCKD1 and MCKD2, have been localized to chromosome 1q21 and 16p12. Independent confirmation of the locations of MCKD1 and MCKD2 in other MCKD families, with or without hyperuricemia and gout, has been reported. The gene for familial juvenile hyperuricemic nephropathy (FJHN), a phenotype that is very similar to MCKD, was recently mapped to 16p12, in a region overlapping with the MCKD2 locus, raising the question as to whether MCKD2 and FJHN are allelic variants of the same disease entity. The ultimate proof of the allelism between MCKD2 and FJHN will be provided by the identification of the responsible gene(s). Identification and characterization of the MCKD and FJHN genes will help to clarify the pathogenesis and classification of hereditary tubulo-interstitial nephritides.
 ...
PMID:Towards the identification of (a) gene(s) for autosomal dominant medullary cystic kidney disease. 1283 29

As a consequence of uromodulin gene mutations, individuals develop precocious hyperuricemia, gout, and progressive renal failure. In vitro studies suggest that pathologic accumulation of uromodulin/Tamm-Horsfall glycoprotein (THP) occurs in the endoplasmic reticulum (ER), but the pathophysiology of renal damage is unclear. It was hypothesized that programmed cell death triggered by accumulation of misfolded THP in the ER causes progressive renal disease. Stably transfected human embryonic kidney 293 cells and immortalized thick ascending limb of Henle's loop cells with wild-type and mutated uromodulin cDNA were evaluated to test this hypothesis. Immunocytochemistry, ELISA, and deglycosylation studies indicated that accumulation of mutant THP occurred in the ER. FACS analyses showed a significant increase in early apoptosis signal in human embryonic kidney 293 and thick ascending limb of Henle's loop cells that were transfected with mutant uromodulin constructs. Colchicine and sodium 4-phenylbutyrate treatment increased secretion of THP from the ER to the cell membrane and into the culture media and significantly improved cell viability. These findings indicate that intracellular accumulation of THP facilitates apoptosis and that this may provide the pathologic mechanism responsible for the progressive renal damage associated with uromodulin gene mutations. Colchicine and sodium 4-phenylbutyrate reverse these processes and could potentially be beneficial in ameliorating the progressive renal damage in uromodulin-associated kidney diseases.
 ...
PMID:Mutant tamm-horsfall glycoprotein accumulation in endoplasmic reticulum induces apoptosis reversed by colchicine and sodium 4-phenylbutyrate. 1613 73

Medullary cystic kidney disease (MCKD) belongs with nephronophthisis (NPH) to the NPH-MCKD complex, a group of inherited tubulointerstitial nephritis which share some morphological and clinical features. Juvenile NPH, the most frequent variant of the complex, is a recessive disease with onset in childhood leading to end stage renal disease (ESRD) within the 2nd decade of life. The most frequent extrarenal involvement is tapeto-retinal degeneration. MCKD is a less frequent disease with dominant inheritance; it is recognized later in life, leading to ESRD at the age of 50 years, and may be associated with hyperuricemia and gout. In an early phase, both NPH and MCKD are pauci-symptomatic, major signs being confined to polyuria. Later in the course, clinical findings are related to the progressive renal insufficiency, such as anemia, uremic symptoms and, in NPH, growth retardation. On renal ultrasound, the kidneys present an increased medullary echogenicity with diminished cortico-medullary differentiation. Renal cysts may be present, usually at corticomedullary boundary. Due to the clinico-pathological identity, the two diseases were considered to be a single disorder, and the compromise appellation of NPH-MCKD complex was suggested. This unifying conception was subsequently refuted following the identification of MCKD dominant families. The recent advances of the molecular genetics changed the traditional classification of NPH-MCKD complex. The majority of cases of juvenile NPH are due to deletion of the NPHP1 gene on chromosome 2q13. Genes for infantile and adolescent NPH have been localized to chromosome 9q22-q31 and 3q22, respectively. A new locus, NPHP4, has been recently mapped on chromosome 1p36. Two genes predisposing to dominant MCKD, MCKD1 and MCKD2, have been localized to chromosome 1q21 and to chromosome 16p12. Moreover, a gene for familial juvenile hyperuricemic nephropathy (FJHN), a phenotype very similar to MCKD, was mapped to 16p12 in a region overlapping with the MCKD2 locus. The proof of the allelism between MCKD2 and FJHN has been recently provided by the identification of four novel uromodulin (UMOD) gene mutations, segregating with the disease phenotype in three families with FJHN and one with family with MCKD2. These data provide the first direct evidence that MCKD2 and FJHN arise from mutation of the UMOD gene and are allelic disorders.
 ...
PMID:Nephronophthisis-medullary cystic kidney disease: from bedside to bench and back again. 1765 3

Familial juvenile hyperuricemic nephropathy (FJHN) is an autosomal-dominant disease characterized by hyperuricemia of underexcretion type, gout, and chronic renal failure. Recent discovery of uromodulin mutations as a cause of FJHN and MCKD2 led a new concept, i.e. uromodulin-associated kidney disease (UAKD). The genotype-phenotype correlation and genetic heterogeneity of FJHN are reviewed.
 ...
PMID:[Familial juvenile hyperuricemic nephropathy (FJHN)]. 1840 15

Mutations in the UMOD gene encoding uromodulin (Tamm-Horsfall glycoprotein) result in the autosomal dominant transmission of progressive renal insufficiency and hypo-uricosuric hyperuricemia leading to gout at an early age. The clinical appearance is characterized by renal insufficiency and gout occurring in the late teenage years, with end-stage kidney disease characteristically developing between 40 and 70 years of age. This report provides a long-term characterization of renal functional decline in three children from one family with a novel UMOD mutation (c.891T>G, p.C297W) who received allopurinol and a low protein diet. While renal functional decline is slow in individuals with UMOD mutations, it may appear early in life and be associated with marked hyperuricemia. Anemia was also noted in this family.
 ...
PMID:Childhood course of renal insufficiency in a family with a uromodulin gene mutation. 2015 Nov 60

Uromodulin (UMOD) mutations are responsible for three autosomal dominant tubulo-interstitial nephropathies including medullary cystic kidney disease type 2 (MCKD2), familial juvenile hyperuricemic nephropathy and glomerulocystic kidney disease. Symptoms include renal salt wasting, hyperuricemia, gout, hypertension and end-stage renal disease. MCKD is part of the 'nephronophthisis-MCKD complex', a group of cystic kidney diseases. Both disorders have an indistinguishable histology and renal cysts are observed in either. For most genes mutated in cystic kidney disease, their proteins are expressed in the primary cilia/basal body complex. We identified seven novel UMOD mutations and were interested if UMOD protein was expressed in the primary renal cilia of human renal biopsies and if mutant UMOD would show a different expression pattern compared with that seen in control individuals. We demonstrate that UMOD is expressed in the primary cilia of renal tubules, using immunofluorescent studies in human kidney biopsy samples. The number of UMOD-positive primary cilia in UMOD patients is significantly decreased when compared with control samples. Additional immunofluorescence studies confirm ciliary expression of UMOD in cell culture. Ciliary expression of UMOD is also confirmed by electron microscopy. UMOD localization at the mitotic spindle poles and colocalization with other ciliary proteins such as nephrocystin-1 and kinesin family member 3A is demonstrated. Our data add UMOD to the group of proteins expressed in primary cilia, where mutations of the gene lead to cystic kidney disease.
 ...
PMID:Uromodulin is expressed in renal primary cilia and UMOD mutations result in decreased ciliary uromodulin expression. 2017 60

Uromodulin (Tamm-Horsfall glycoprotein) is the most common protein excreted in the urine of healthy individuals, yet its function remains unclear. Mutations in the UMOD gene encoding uromodulin result in a marked decrease in the synthesis of uromodulin, as well as the accumulation of abnormal uromodulin in tubular cells, leading to tubular cell death. UMOD gene mutations are responsible for the autosomal dominant inheritance of chronic interstitial disease, leading to the need for renal replacement in the third through seventh decades of life. Individuals with UMOD mutations also suffer from hyperuricemia in childhood, and often suffer from gout in their teenage years. A similar clinical syndrome causing the autosomal dominant inheritance of chronic kidney disease, hyperuricemia, and anemia has recently been attributed to mutations in the REN gene encoding renin. Recently, polymorphisms in the UMOD gene have been found responsible for increased urinary uromodulin production and an increased risk of chronic kidney disease. This review summarizes information on uromodulin biology and clinical manifestations of mutations in the UMOD gene, as well as similar inherited interstitial diseases. It provides new information regarding UMOD gene polymorphisms and their association with chronic kidney disease.
 ...
PMID:Uromodulin-associated kidney disease. 2107 70