Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0025362 (mental retardation)
 15,878 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Leg ulcers may be caused by many different diseases. Most frequently, they are due to vasculopathies, to a lesser extent to metabolic, neuropathic or hematologic diseases. Neoplasms, connective tissue diseases, infections, trauma, and panniculitis should also be included in the differential diagnosis. A 38-year-old Caucasian female patient with hereditary prolidase deficiency developed progressive and very painful leg ulcers. The ulcers first appeared in childhood and did not respond to various treatments. Additional features of prolidase deficiency included mental retardation, short stature, extensive dental caries, and multiple malar teleangiectases. Hereditary prolidase deficiency is a very rare autosomal recessive disease. It is caused by heterogeneous mutations of the prolidase gene and affects many aspects of protein metabolism. Ion exchange chromatography and high voltage electrophoresis of urine can prove the suspected diagnosis. So far, there is no efficient therapy for hereditary prolidase deficiency. All reported treatment attempts have ended in failure.
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PMID:[Hereditary prolidase deficiency. Contribution to differential therapy refractory leg ulcer diagnosis]. 1111 49

Prolidase deficiency is a rare, inherited disorder characterized by ulceration of the skin, mental retardation, and massive urinary excretion of imidodipeptides. Most patients also have recurrent infections, an unusual facial appearance, and splenomegaly. We describe a girl presenting with chronic dermatitis, recurrent respiratory tract infections since her first months of life, and facial features characteristic of prolidase deficiency. The diagnosis of prolidase deficiency was made at 4.5 months of age. The immunologic study in this patient showed an extreme and progressive increase of total immunoglobulin E (IgE) in serum (reaching the value of 77,600 IU/l) and defective chemotactic function of the neutrophils. Treatment with a hyper-proteic diet supplemented with ascorbic acid, manganese chlorite, and topical proline resulted in reduction of the frequency and severity of the infections and significant improvement of the skin lesions. The authors discuss the immunologic alterations and the favorable evolution with treatment in this patient.
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PMID:Prolidase deficiency with hyperimmunoglobulin E: a case report. 1200 Apr 88

Prolidase, a ubiquitously distributed dipeptidase, is involved in the latter stage of degradation of endogenous and dietary proteins and is particularly important in collagen catabolism. It hydrolyzes dipeptides containing proline or hydroxyproline at the C-terminal position. Mutations in the gene encoding for prolidase cause prolidase deficiency (PD), an autosomal recessive disorder mainly characterized by skin lesions, mental retardation and recurrent infectious. In this work we reported the identification of the molecular defect in five PD patients. Direct sequencing of PCR amplified genomic DNA showed a homozygous G>A transversion in two siblings leading to a G448R substitution. A heterozygous IVS11+1G>C transition causing the skipping of exon 11 and a null allele were detected in a third proband. In two unrelated patients, a homozygous IVS7-1G>A transversion was identified and shown to cause multiple alternative spliced transcripts. All the mutations result in loss of prolidase activity. Long-term cultured fibroblasts from these PD patients were used to develop an in vitro model that allowed investigation of the affected cells. Light and electron microscopy revealed that PD cells were more round and branched out than controls with increased cytosolic vacuolization, interruptions of the plasma membrane, mitochondria swelling, mitochondrial matrix and cristae modifications. JC-1 labeling showed decreased mitochondrial membrane potential. A significant intracellular accumulation of the Gly-Pro dipeptide was detected by capillary electrophoresis analysis. Our results provide the first evidence that absence of prolidase activity causes the activation of a necrosis-like cellular death, which could be responsible for the typical skin lesions in PD.
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PMID:Mutation analysis of five new patients affected by prolidase deficiency: the lack of enzyme activity causes necrosis-like cell death in cultured fibroblasts. 1238 72

Prolidase deficiency is an autosomal recessive inherited disease characterized clinically by frequent infections, mental retardation, and various skin lesions. Fundamental treatments for these manifestations have not been established. We performed adenovirus-mediated gene transfer of human prolidase cDNA into fibroblasts from patients with prolidase deficiency. Infection with the adenovirus vector carrying human prolidase cDNA increased prolidase activity in fibroblasts up to approximately 7.5 times of that of normal control fibroblasts. This indicates the feasibility of adenovirus-mediated gene therapy to treat patients with prolidase deficiency in the future.
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PMID:Amelioration of prolidase deficiency in fibroblasts using adenovirus mediated gene transfer. 1250 86

Genetic deficiency of prolidase can lead to severe problems in child development, including mental retardation. However, the exact pathogenesis of the disease is unclear. To understand the enzyme's physiologic functions, we studied the regulation of rat intestinal prolidase. The results indicated that 1) the activities of intestinal prolidase and its kinetic parameters (Km and Vmax) are site-dependent; 2) the jejunal prolidase activity was the most sensitive to the dietary restriction, and the duodenal and jejunal but not colonic kinetic parameters changed with dietary restriction; 3) the pH activity profile of jejunal prolidase at 24 h postfeeding was different from that at 48 h postfeeding, whereas the inhibition profiles of prolidase were qualitatively independent of dietary restriction; and 4) old-aged rats have lower prolidase activities in the small intestine. We also purified rat intestinal prolidase I to homogeneity. The characterization study indicated that the purified rat intestinal prolidase I is fairly similar to prolidase I from other species with a molecular weight of 116,000, which consisted of two monomers, 58,000 D each. The purified prolidase I has a Km value of 178 microM and a Vmax value of 601 micromol x min-1. mg protein-1. Screening of a rat intestinal cDNA library produced a 1.8-kb fragment that encodes the rat intestinal prolidase. This enzyme has 494 deduced amino acid sequence, which is 96% or 86% identical to mouse or human erythrocyte prolidase I. This represents the first report of a successful attempt to purify and clone an intestinal prolidase and of investigation to study prolidase regulation by diet.
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PMID:Functional and molecular characterization of rat intestinal prolidase. 1264 27

Prolidase deficiency (PD) is a rare autosomal recessive disorder characterized mainly by skin lesions of the legs and feet, mental retardation, and respiratory infections. Mutations at the PEPD locus, located on chromosome 19, are responsible for this disease. We identified a new PEPD allele in two unrelated Portuguese PD patients by analyses of reverse transcribed PCR-amplified cDNA. We used SSCP analysis of seven overlapping fragments spanning the entire coding region of the gene and detected abnormal SSCP bands in two of them: PD3 (nt 425-743) and PD4 (nt 661-973). Direct sequencing of the mutant cDNA and genomic DNA revealed a new homozygous 3-bp deletion (Y231del) in both cases. Transient expression in PD fibroblasts of wild-type and mutant prolidase cDNA confirmed reduced activity of the construct carrying the 3-bp deletion. The mutation results in a loss of prolidase activity in skin fibroblasts. Intracellular accumulation of Gly-Pro dipeptide in long-term cultured fibroblasts was detected by capillary electrophoresis. The mutation falls in the alpha2 domain of the "pita bread" structure proposed for E. coli and human prolidase by Bazan et al. on the bases of their sequence homology with E. coli methionine aminopeptidase. Taking into account the effects of the described mutations on stability and activity of the enzyme, we propose the identification of three different functional regions.
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PMID:Characterization of a new PEPD allele causing prolidase deficiency in two unrelated patients: natural-occurrent mutations as a tool to investigate structure-function relationship. 1530 82

Prolidase is a cytosolic exopeptidase whose deficiency causes the development of a rare autosomal recessive disorder known as Prolidase Deficiency (PD). The main manifestations of PD are intractable ulcerations of the skin, recurrent infections and mental retardation. At this time only a hazardous and expensive chronic therapy based on blood transfusions is the suggested treatment for PD. The aim of this work was to investigate the capability of utilizing liposomes as enzyme carriers: these vesicular systems have been recently evaluated as protein carriers for their potential in terms of "in vivo" localization, drug release and for protein stabilization in biological fluids. Liposomes were prepared, with a 1:1 PC:Col molar ratio with or without DSPE-PEG, by a thin-film hydration. Ex-vivo experiments were performed, incubating prolidase loaded liposomes with cultured fibroblasts from PD patients and from controls, to determine the amount of active enzyme delivered to cells. Evaluation of liposomes toxicity on cultured skin fibroblasts showed that liposomes did not interfere with cellular growth. Results showed that all the active prolidase encapsulated in the liposomes was completely vehiculated inside fibroblasts after 6 days incubation. SEM analysis suggests that prolidase is vehiculated inside the cell through liposome endocytosis.
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PMID:Intracellular delivery of liposome-encapsulated prolidase in cultured fibroblasts from prolidase-deficient patients. 1565 44

Prolidase deficiency (PD) is a recessive disorder of the connective tissue caused by mutations in the prolidase, a specific peptidase, cleaving the dipeptides with a C-terminal prolyl and hydroxyprolyl residue. PD is a complex syndrome characterized mainly by intractable skin lesions, recurrent respiratory infections and mental retardation. The relation between prolidase biological functions and the disease is still largely unknown. We studied the effect of a prolidase inhibitor, N-benzyloxycarbonyl-l-proline (Cbz-Pro), in vitro on prolidase from human fibroblasts and in vivo on murine erythrocytes prolidase. A 90% inhibition was detected incubating cellular extracts at 1:1 ratio of Gly-Pro substrate: Cbz-Pro inhibitor. Pulse experiments performed incubating human fibroblasts with 6 mM Cbz-Pro revealed that the inhibitor uptake was completed in about 1 min. The Cbz-Pro uptake was saturable and pH dependent. Long-term incubation of fibroblasts with Cbz-Pro caused mitochondria depolarization and increased cellular death as reported for long-term culture of fibroblasts from PD patients. An inhibitory effect of Cbz-Pro has also been shown in vivo. Our results demonstrated that Cbz-Pro is a potent inhibitor of prolidase in cultured fibroblasts and it can be used in vivo to better characterize the prolidase enzyme and further investigate PD physiopathology.
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PMID:N-benzyloxycarbonyl-L-proline: an in vitro and in vivo inhibitor of prolidase. 1587 28

Prolidase is a Mn(2+)-dependent dipeptidase that cleaves imidodipeptides containing C-terminal proline or hydroxyproline. In humans, a lack of prolidase activity causes prolidase deficiency, a rare autosomal recessive disease, characterized by a wide range of clinical outcomes, including severe skin lesions, mental retardation, and infections of the respiratory tract. In this study, recombinant prolidase was produced as a fusion protein with an N-terminal histidine tag in eukaryotic and prokaryotic hosts and purified in a single step using immobilized metal affinity chromatography. The enzyme was characterized in terms of activity against different substrates, in the presence of various bivalent ions, in the presence of the strong inhibitor Cbz-Pro, and at different temperatures and pHs. The recombinant enzyme with and without a tag showed properties mainly indistinguishable from those of the native prolidase from fibroblast lysate. The protein yield was higher from the prokaryotic source, and a detailed long-term stability study of this enzyme at 37 degrees C was therefore undertaken. For this analysis, an 'on-column' digestion of the N-terminal His tag by Factor Xa was performed. A positive effect of Mn(2+) and GSH in the incubation mixture and high stability of the untagged enzyme are reported. Poly(ethylene glycol) and glycerol had a stabilizing effect, the latter being the more effective. In addition, no significant degradation was detected after up to 6 days of incubation with cellular lysate. Generation of the prolidase in Escherichia coli, because of its high yield, stability, and similarity to native prolidase, appears to be the best approach for future structural studies and enzyme replacement therapy.
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PMID:Human recombinant prolidase from eukaryotic and prokaryotic sources. Expression, purification, characterization and long-term stability studies. 1708 Nov 96

Prolidase deficiency (PD) is a rare autosomal recessive connective tissue disorder caused by mutations in the prolidase gene. The PD patients show a wide range of clinical outcomes characterised mainly by intractable skin ulcers, mental retardation and recurrent respiratory infections. Here we describe five different PEPD mutations in six European patients. We identified two new PEPD mutant alleles: a 13 bp duplication in exon 8, which is the first reported duplication in the prolidase gene and a point mutation resulting in a change in amino acid E412, a highly conserved residue among different species. The E412K substitution is responsible for the first reported phenotypic variability within a family with severe and asymptomatic outcomes.
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PMID:Molecular characterisation of six patients with prolidase deficiency: identification of the first small duplication in the prolidase gene and of a mutation generating symptomatic and asymptomatic outcomes within the same family. 1714 20


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