Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0030305 (pancreatitis)
 16,014 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We analyzed the molecular defects in the lipoprotein lipase gene of a patient with type I hyperlipidemia suffering from recurrent pancreatitis, indicative for lipoprotein lipase deficiency. Postheparin lipoprotein lipase activity in the patient was decreased by 70%. Direct genomic sequencing revealed compound heterozygosity for two mutation: the well-known Gly188-->Glu and a new Val69-->Leu substitution. Val69 is situated in a conserved hydrophobic region of the lipoprotein lipase protein, and the substitution with leucine gives rise to a 80% decrease in specific catalytic activity, as supported by site-directed mutagenesis experiments, followed by expression in COS-cells. The combination of both defects in the lipoprotein lipase gene was incidentally associated with severe clinical expression of disease, and triglyceride levels of more than 30 mmol/l were measured. In our patient, triglyceride levels wer usually below 10 mmol/l. We, therefore, postulate that the residual LPL activity in our patient is usually sufficient to keep the triglyceride level within bounds and expression of disease occurred only when conditions such as alcohol abuse or poor compliance to diet were present.
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PMID:A compound heterozygote for lipoprotein lipase deficiency, Val69-->Leu and Gly188-->Glu: correlation between in vitro LPL activity and clinical expression. 791 54

We report the molecular basis of familial chylomicronemia and recurrent pancreatitis in five members of a large Dutch family. All patients had normal plasma hepatic lipase and apoC-II levels, but absent lipoprotein lipase (LPL) catalytic activity and low LPL mass in postheparin plasma. The mutation in the LPL gene was characterized as a G715-->A substitution in the last nucleotide of exon 4, resulting in a substitution of Ser for Gly154. PCR amplification of exons 4 + 5 from the patients' mRNA, followed by direct sequencing, revealed normal splicing of intron 4. The mutation creates a BfaI restriction site that allows rapid screening of family members for the mutation. Reproduction of this mutation in LPL-cDNA by site-directed mutagenesis, followed by transient expression in COS-B cells, revealed production of a catalytically inactive enzyme. The Gly154-->Ser substitution appears in a conserved beta-sheet region, in close proximity to Asp156, which is part of the catalytic triad. These studies show that changes to residues close to Asp156 can have profound effects on catalytic activity of LPL.
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PMID:Recurrent pancreatitis and chylomicronemia in an extended Dutch kindred is caused by a Gly154-->Ser substitution in lipoprotein lipase. 830 Dec 30

A proband with chylomicronemia, pancreatitis, and non-insulin-dependent diabetes (NIDDM) bears two different mutations in exon 3 of the lipoprotein lipase (LPL) gene: a missense mutation, 75Arg-->Ser, inherited through the paternal line and a truncation, 73Tyr-->Ter, through the maternal line. NIDDM appeared to be independently segregating. The R75S mutant was studied in extracts and media from transfected COS-1 cells. Detectable amounts of catalytically competent R75S LPL suggested destabilization of the active homodimer as with exon 5 mutants (Hata et al. 1992. J. Biol. Chem. 267:20132-20139). Hydrolysis of a short-chain fatty acid ester indicated that R75S does not directly affect activation of LPL by apoC-II. Subjects with NIDDM and wild-type LPL, and nondiabetic middle-aged carriers of the 73Tyr-->Ter truncation had moderate hypertriglyceridemia (260-521 mg/dl) and reduced high density lipoprotein cholesterol. A maternal aunt with NIDDM carried the truncation. Her phenotype (triglycerides of 5,300 mg/dl, eruptive xanthomatosis, and recurrent pancreatitis) was as severe as that in homozygotes or compound heterozygotes. We conclude: (a) diabetic carriers of dysfunctional LPL alleles are at risk for severe lipemia; and (b) the physiologic defects in NIDDM may be additive or synergistic with heterozygous LPL deficiency.
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PMID:Mutations in exon 3 of the lipoprotein lipase gene segregating in a family with hypertriglyceridemia, pancreatitis, and non-insulin-dependent diabetes. 832 86

To characterize at the molecular level the pancreatic emergency program set up by the pancreatic cells in response to pancreatitis, we have developed a strategy in which the phenotype of the pancreatitis affected pancreas is established by characterization of a large number of its transcripts. Herein, we describe the cloning, sequence, and expression of a new gene, named p8, which is strongly activated in pancreatic acinar cells during the acute phase of pancreatitis, in developing pancreas and during pancreatic regeneration. In acinar cells, p8 mRNA is expressed rapidly and specifically in response to cellular pancreatitis-induced injury; its induction occurred almost similarly in edematous and necrohemorrhagic pancreatitis, indicating that p8 mRNA is maximally activated even in response to a mild pancreatic injury. Furthermore, in vitro studies suggest that p8 mRNA is induced in pancreatic and non-pancreatic cells in response to some apoptotic stimuli. p8 acts as a promoter of cellular growth factor when its cDNA is transfected into COS-7 and AR4-2J cells. Although we failed to identify p8-related sequences, analysis of its primary and secondary structure suggests that p8 is a basic helix-turn-helix-containing gene with slight homology to several homeotic genes and sufficient signal to be targeted to the nucleus. We therefore propose p8 as a putative transcriptional factor which can regulate pancreatic growth.
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PMID:Cloning and expression of the rat p8 cDNA, a new gene activated in pancreas during the acute phase of pancreatitis, pancreatic development, and regeneration, and which promotes cellular growth. 940 44

Functional deficiency of lipoprotein lipase (LPL) was found in a patient with severe hypertriglyceridemia. The patient was 39-year-old man with a plasma triglyceride level of 2032 mg/dl, and suffered from recurrent pancreatitis. His post heparin plasma LPL mass was almost normal, but the LPL activity was remarkably decreased. Gene analysis showed that homozygote missense mutation (204 Asp (GAC)-Glu (GAG)) exists in exon 5 of LPL gene. The patient LPL purified from post heparin plasma scarcely hydrolyzed VLDL-triglyceride and also triolein emulsified with Triton X-100 or phosphatidylcholine. When phosphatidylethenolamine, phosphatidylserine and cardiolipin were used as an emulsifier for triolein, triolein-hydrolyzing activity of the patient's LPL was observed and was much higher than that of wild-type LPL. Mutant LPL gene (Asp204-Glu) was made by site-direct mutagenesis and was transfected to COS-1 cell. The expressed LPL (Asp204-Glu) also showed the same properties. These results suggested that the LPL (Asp204-Glu) is a functional deficiency, and the activity could be recovered by using acidic phospholipids as an emulsifier.
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PMID:The recovery of dysfunctional lipoprotein lipase (Asp204-Glu) activity by modification of substrate. 1587 72

Lipoprotein lipase (LPL) is widely expressed in skeletal muscles, cardiac muscles as well as adipose tissue and involved in the catabolism of triglyceride. Herein we have systematically characterized two novel loss-of-function mutations in LPL from a Chinese family in which afflicted members were manifested by severe hypertriglyceridemia and recurrent pancreatitis. DNA sequencing revealed that the proband was a heterozygote carrying a novel c.T928C (p.C310R) mutation in exon 6 of the LPL gene. Another member of the family was detected to be a compound heterozygote who along with the c.T928C mutation also carried a novel missense mutation c.A1187T (p.E396V) in exon 8 of the LPL gene. Furthermore, COS-1 cells were transfected with lentiviruses containing the mutant LPL genes. While C310R markedly reduced the overall LPL protein level, COS-1 cells carrying E396V or double mutations contained similar overall LPL protein levels to the wild-type. The specific activity of the LPL mutants remained at comparable magnitude to the wild-type. However, few LPL were detected in the culture medium for the mutants, suggesting that both mutations caused aberrant triglyceride catabolism. More specifically, E396V and double mutations dampened the transport of LPL to the cell surface, while for the C310R mutation, reducing LPL protein level might be involved. By characterizing these two novel LPL mutations, this study has expanded our understanding on the pathogenesis of familial hypertriglyceridemia (FHTG).
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PMID:Severe hypertriglyceridemia due to two novel loss-of-function lipoprotein lipase gene mutations (C310R/E396V) in a Chinese family associated with recurrent acute pancreatitis. 2854 60