1/12. Triglyceride-induced diabetes associated with familial lipoprotein lipase deficiency.Raised plasma triglycerides (TGs) and nonesterified fatty acid (NEFA) concentrations are thought to play a role in the pathogenesis of insulin-resistant diabetes. We report on two sisters with extreme hypertriglyceridemia and overt diabetes, in whom surgical normalization of TGs cured the diabetes. In all of the family members (parents, two affected sisters, ages 18 and 15 years, and an 11-year-old unaffected sister), we measured oral glucose tolerance, insulin sensitivity (by the euglycemic-hyperinsulinemic clamp technique), substrate oxidation (indirect calorimetry), endogenous glucose production (by the [6,6-2H2]glucose technique), and postheparin plasma lipoprotein lipase (LPL) activity. In addition, GC-clamped polymerase chain reaction-amplified dna from the promoter region and the 10 coding LPL gene exons were screened for nucleotide substitution. Two silent mutations were found in the father's exon 4 (Glu118 Glu) and in the mother's exon 8 (Thr361 Thr), while a nonsense mutation (Ser447 Ter) was detected in the mother's exon 9. Mutations in exons 4 and 8 were inherited by the two affected girls. At 1-2 years after the appearance of hyperchylomicronemia, both sisters developed hyperglycemia with severe insulin resistance. Because medical therapy (including high-dose insulin) failed to reduce plasma TGs or control glycemia, lipid malabsorption was surgically induced by a modified biliopancreatic diversion. Within 3 weeks of surgery, plasma TGs and NEFA and cholesterol levels were drastically lowered. Concurrently, fasting plasma glucose levels fell from 17 to 5 mmol/l (with no therapy), while insulin-stimulated glucose uptake, oxidation, and storage were all markedly improved. Throughout the observation period, plasma TG levels were closely correlated with both plasma glucose and insulin concentrations, as measured during the oral glucose tolerance test. These cases provide evidence that insulin-resistant diabetes can be caused by extremely high levels of TGs.- - - - - - - - - - ranking = 1keywords = hypertriglyceridemia (Clic here for more details about this article) |
2/12. A gene for congenital generalized lipodystrophy maps to human chromosome 9q34.Congenital generalized lipodystrophy (CGL, Berardinelli-Seip syndrome, OMIM # 269700) is a rare autosomal recessive disorder characterized by near complete absence of adipose tissue from birth. Affected individuals have marked insulin resistance, hypertriglyceridemia and acanthosis nigricans, and develop diabetes mellitus during teenage years. The genetic defect for CGL is unknown. A semi-automated genome-wide scan with a set of highly polymorphic short tandem repeats (STR) was carried out in 17 well-characterized pedigrees and identified a locus for CGL to chromosome 9q34. The maximum two-point lod score obtained was 3.6 at D9S1818 (theta(max) = 0.05). There was evidence for genetic heterogeneity (alpha = 0.73) and 2 of the pedigrees were unlinked. Multipoint linkage analysis excluding the 2 unlinked families yielded a peak lod score of 5.4 between loci D9S1818 and D9S1826. The CGL1 critical region harbors a plausible candidate gene encoding the retinoid x receptor alpha (RXRA) that plays a central role in adipocyte differentiation. Identification of the CGL gene(s) will contribute to our understanding of the adipocyte differentiation and elucidation of the mechanisms of insulin resistance in disorders of adipose tissue.- - - - - - - - - - ranking = 1keywords = hypertriglyceridemia (Clic here for more details about this article) |
3/12. Enhanced intra-abdominal visceral fat accumulation in patients with Werner's syndrome.OBJECTIVE: Studies were made on the abnormality of glucose and lipid metabolism and its cause in four patients with Werner's syndrome to infer the reason for accelerated atherogenesis in this syndrome. RESULTS: Of these four patients, hypercholesterolemia was found in three, hypertriglyceridemia in four, hypoalphalipoproteinemia in two and hypertension in two. All the patients had insulin-resistant diabetes mellitus and three of them had apparent hyperinsulinemia. Abdominal computed tomography revealed that all of them had visceral fat obesity, namely augumented intra-abdominal adipose tissue. CONCLUSION: The clinical features of these patients resemble those recently designated as insulin resistant syndrome (syndrome X) or visceral fat syndrome. The metabolic abnormality may be one of important factors in the accelerated atherogenesis in this syndrome.- - - - - - - - - - ranking = 1keywords = hypertriglyceridemia (Clic here for more details about this article) |
4/12. syndrome of lipodystrophy, hyperlipidemia, insulin resistance, and diabetes in treated patients with human immunodeficiency virus infection.OBJECTIVE: To describe the syndrome of lipodystrophy, hyperlipidemia, insulin resistance, and diabetes in patients with human immunodeficiency virus (hiv) infection treated with protease inhibitor drugs. methods: This is a case series of patients referred from an infectious disease clinic to a diabetes-endocrinology clinic in an academic medical center because of severe metabolic problems that occurred during the course of otherwise-successful treatment of hiv infection. The clinical course, abnormalities on physical examination, laboratory data, and complications are described and analyzed. The pathogenesis of the syndrome is discussed and compared with that of type 2 diabetes, lipoatrophic diabetes, and mouse models of lipodystrophy. RESULTS: In six male patients receiving antiretroviral therapy for hiv infection, a syndrome of lipoatrophy of the face, legs, and buttocks, hyperlipidemia (predominantly hypertriglyceridemia), and type 2 diabetes mellitus was noted. Two patients had pronounced abdominal obesity, in contrast to their thin extremities. Five of the six patients were receiving protease inhibitor drugs, which have been thought to contribute to metabolic abnormalities. In two patients, ischemic heart disease had developed. CONCLUSION: protease inhibitors frequently cause insulin resistance and lipoatrophy in subcutaneous adipose tissue. These abnormalities are associated with visceral adiposity, hyperlipidemia, diabetes, and cardiovascular consequences and represent an important and unsolved problem in the treatment of hiv-infected patients.- - - - - - - - - - ranking = 1keywords = hypertriglyceridemia (Clic here for more details about this article) |
5/12. A family-based study of hyperinsulinemia and hypertriglyceridemia in heterozygous lipoprotein lipase deficiency.CASE REPORT: A case is presented of predisposing a patient's father with obligate heterozygous lipoprotein lipase (LPL) deficiency to mild hypertriglyceridemia in Japanese I-family members (n=8) with patient DI, who was a compound heterozygote for a novel missense mutation of G154V (GG(716)C-->GTC/Gly(154) Val) in exon 5 and a novel splice mutation (Int8/5'-dss/t( 2)c; a T-to-C transition in the invariant GT at position 2 of the 5' donor splice site (dss)) in intron 8 of the LPL gene. RESULTS: The patient's father and paternal grandmother were heterozygotes for the Int8/5'-dss/t( 2)c allele, while the patient's mother and maternal grandmother were heterozygotes for the G154V allele. These four heterozygous carriers with one defective LPL allele showed 45-57% of the mean LPL activity and mass in the post-heparin plasma (PHP) observed in normal individuals. Among the four heterozygous carriers, the patient's father, who was <40 years old, nonobese and hyperinsulinemia, manifested mild hypertriglyceridemia (type IV hyperlipoproteinemia). The remaining three healthy heterozygous carriers (two were >40 years old and the other was <40 years old) were all normolipidemic state. CONCLUSION: In this family, hyperinsulinemia as a marker of insulin resistance may be a strong determinant of hypertriglyceridemia in the carrier with heterozygous LPL deficiency.- - - - - - - - - - ranking = 7keywords = hypertriglyceridemia (Clic here for more details about this article) |
6/12. A new clinical condition linked to a novel mutation in lamins A and C with generalized lipoatrophy, insulin-resistant diabetes, disseminated leukomelanodermic papules, liver steatosis, and cardiomyopathy.A-Type lamins, arising from the LMNA gene, are intermediate filaments proteins that belong to the lamina, a ubiquitous nuclear network. Naturally occurring mutations in these proteins have been shown to be responsible for several distinct diseases that display skeletal and/or cardiac muscle or peripheral nerve involvement. These include familial partial lipodystrophy of the Dunnigan type and the mandibuloacral dysplasia syndrome. The pathophysiology of this group of diseases, often referred to as laminopathies, remains elusive. We report a new condition in a 30-yr-old man exhibiting a previously undescribed heterozygous R133L LMNA mutation. His phenotype associated generalized acquired lipoatrophy with insulin-resistant diabetes, hypertriglyceridemia, hepatic steatosis, hypertrophic cardiomyopathy with valvular involvement, and disseminated whitish papules. Immunofluorescence microscopic analysis of the patient's cultured skin fibroblasts revealed nuclear disorganization and abnormal distribution of A-type lamins, similar to that observed in patients harboring other LMNA mutations. This observation broadens the clinical spectrum of laminopathies, pointing out the clinical variability of lipodystrophy and the unreported possibility of hypertrophic cardiomyopathy and skin involvement. It emphasizes the fact that the diagnosis of genetic alterations in A-type lamins requires careful and complete clinical and morphological investigations in patients regardless of the presenting signs.- - - - - - - - - - ranking = 1keywords = hypertriglyceridemia (Clic here for more details about this article) |
7/12. Generalized lipodystrophy: in vivo evidence for hypermetabolism and insulin-resistant lipid, glucose, and amino acid kinetics.Stable isotope tracers and indirect calorimetry were used to evaluate whole-body energy, glucose, lipid, and amino acid metabolism in a patient with generalized lipodystrophy during basal conditions and in response to insulin therapy. The results were compared with those obtained in previous studies in normal volunteers. The basal rate of glucose production (33.7 mumol/kg.min) was three times higher than normal. The basal rate of glycerol appearance in blood, an index of lipolysis, was 60% greater than normal when expressed per kilogram body weight (3.82 mumol/kg.min), but was more than 10 times normal when expressed per kilogram body fat mass (123.2 mumol/kg.min) because of the marked decrease in body fat in our patient (3% of total body weight). leucine rate of appearance, an index of protein breakdown, and nonoxidative leucine disposal, an index of protein synthesis, were also greater than normal. Resting energy expenditure (REE) was 30% greater than normal. The effect of insulin infusion on these metabolic parameters was markedly blunted. These metabolic abnormalities help explain many of the clinical findings such as hyperglycemia, hypertriglyceridemia, fat depletion, hepatomegaly, and steatosis observed in patients with lipodystrophy. Ineffective insulin function in many tissues appears to be an important factor in the pathophysiology of lipodystrophy.- - - - - - - - - - ranking = 1keywords = hypertriglyceridemia (Clic here for more details about this article) |
8/12. A LMNA splicing mutation in two sisters with severe Dunnigan-type familial partial lipodystrophy type 2.CONTEXT: To date, all cases of familial partial lipodystrophy type 2 (FPLD2; Mendelian Inheritance in Man 151660) result from missense mutations in LMNA, which encodes nuclear lamin A/C (Mendelian Inheritance in Man 150330). OBJECTIVE: The objective of the study was to carry out mutational analysis of LMNA in two sisters with a particularly severe FPLD2 phenotype. DESIGN: This was a descriptive case report with molecular studies. SETTING: The study was conducted at a referral center. patients: We report two sisters of South Asian origin. The first presented with acanthosis nigricans at age 5 yr, diabetes with insulin resistance, hypertension and hypertriglyceridemia at age 13 yr, and partial lipodystrophy starting at puberty. Her sister and their mother had a similar metabolic profile and physical features, and their mother died of vascular disease at age 32 yr. INTERVENTIONS: There were no interventions. MAIN OUTCOME MEASURES AND RESULTS: LMNA sequencing showed that the sisters were each heterozygous for a novel G>C mutation at the intron 8 consensus splice donor site, which was absent from the genomes of 300 healthy individuals. The retention of intron 8 in mRNA predicted a prematurely truncated lamin A isoform (516 instead of 664 amino acids) with 20 nonsense 3'-terminal residues. The mutant lamin A isoform failed to interact normally with emerin and failed to localize to the nuclear envelope. CONCLUSIONS: This is the first LMNA splicing mutation to be associated with FPLD2, and it causes a severe clinical and metabolic phenotype.- - - - - - - - - - ranking = 1keywords = hypertriglyceridemia (Clic here for more details about this article) |
9/12. Medical therapy for the syndrome of familial virilization, insulin resistance, and acanthosis nigricans.In the syndrome of familial virilization, insulin resistance, and acanthosis nigricans, the interrelationships are not understood. Twin sisters were studied, along with a lesser affected sister and mother. They manifested amenorrhea, hirsutism, masculinization, hypertension, hyperinsulinemia, hypertriglyceridemia, and hyperprolactinemia. Medical therapy with a gonadotropin-releasing hormone agonist plus an antiandrogen resulted in reversal of the hirsutism, yet with preservation of potential fertility. In response to luteinizing hormone (LH) and follicle-stimulating hormone suppression, there was normalization of the serum androgens, but not of the hyperinsulinemia, hypertriglyceridemia, hyperprolactinemia, hypertension, or acanthosis nigricans. Conclusions: (1) This syndrome may be familial. (2) Medical therapy for the virilization is successful. (3) The hyperandrogenemia is primarily LH dependent and not primarily insulin dependent, although insulin may have an amplification effect. (4) Hyperinsulinemia, hypertriglyceridemia, hyperprolactinemia, and the hypertension are not androgen dependent.- - - - - - - - - - ranking = 3keywords = hypertriglyceridemia (Clic here for more details about this article) |
10/12. Alterations of maternal metabolism in normal and diabetic pregnancies: differences in insulin-dependent, non-insulin-dependent, and gestational diabetes.In normal and diabetic pregnancies, the placenta functions as a complex endocrine gland that modulates all classes of maternal nutrients to the fetus. The metabolic alterations of normal pregnancy are diabetogenic and associated with modest resistance to endogenous insulin. pregnant women with carbohydrate intolerance represent three metabolically heterogeneous groups: type I (insulin-dependent), type II (non-insulin-dependent), and gestational diabetes. patients with type I diabetes are at risk for ketosis and require replacement therapy because of a deficient production of insulin. They have decreased 24-hour, around-the-clock levels of c-peptide and glucagon, and lower nocturnal cortisol values and higher 24-hour prolactin levels than those of women with type II diabetes. Type II pregnant diabetic patients are not prone to ketosis and are more resistant to endogenous and exogenous insulin. They have higher fasting and meal-stimulated levels of c-peptide, accentuated fasting hypertriglyceridemia, and significantly lower high-density lipoprotein cholesterol levels than those of normal or type I women. In gestational diabetes, the metabolic stress of pregnancy evokes reversible hyperglycemia which may be associated with either a surfeit or a deficiency of insulin. These metabolic differences among diabetic pregnant women could have implications for placental structure and function that might influence fetal growth.- - - - - - - - - - ranking = 1keywords = hypertriglyceridemia (Clic here for more details about this article) |
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