ß- and α-cell dysfunctions in africans with ketosis-prone atypical diabetes during near-normoglycemic remission.

OBJECTIVE: Ketosis-prone atypical diabetes (KPD) is a subtype of diabetes in which the pathophysiology is yet to be unraveled. The aim of this study was to characterize ß- and α-cell functions in Africans with KPD during remission. RESEARCH DESIGN AND METHODS: We characterized ß- and α-cell functions in Africans with KPD during remission. The cohort comprised 15 sub-Saharan Africans who had been insulin-free for a median of 6 months. Patients in remission were in good glycemic control (near-normoglycemic) and compared with 15 nondiabetic control subjects matched for age, sex, ethnicity, and BMI. Plasma insulin, C-peptide, and glucagon concentrations were measured in response to oral and intravenous glucose and to combined intravenous arginine and glucose. Early insulin secretion was measured during a 75-g oral glucose tolerance test. Insulin secretion rate and glucagon were assessed in response to intravenous glucose ramping. RESULTS: Early insulin secretion and maximal insulin secretion rate were lower in patients compared with control participants. In response to combined arginine and glucose stimulation, maximal insulin response was reduced. Glucagon suppression was also decreased in response to oral and intravenous glucose but not in response to arginine and insulin. CONCLUSIONS: Patients with KPD in protracted near-normoglycemic remission have impaired insulin response to oral and intravenous glucose and to arginine, as well as impaired glucagon suppression. Our results suggest that ß- and α-cell dysfunctions both contribute to the pathophysiology of KPD.

Fetal exposure to maternal type 1 diabetes is associated with renal dysfunction at adult age.

OBJECTIVE: In animal studies, hyperglycemia during fetal development reduces nephron numbers. We tested whether this observation translates into renal dysfunction in humans by studying renal functional reserve in adult offspring exposed in utero to maternal type 1 diabetes. RESEARCH DESIGN AND METHODS: We compared 19 nondiabetic offspring of type 1 diabetic mothers with 18 offspring of type 1 diabetic fathers (control subjects). Glomerular filtration rate ((51)Cr-EDTA clearance), effective renal plasma flow ((123)I-hippurate clearance), mean arterial pressure, and renal vascular resistances were measured at baseline and during amino acid infusion, which mobilizes renal functional reserve. RESULTS: Offspring of type 1 diabetic mothers were similar to control subjects for age (median 27, range 18-41, years), sex, BMI (23.1 ± 3.7 kg/m(2)), and birth weight (3,288 ± 550 vs. 3,440 ± 489 g). During amino acid infusion, glomerular filtration rate and effective renal plasma flow increased less in offspring of type 1 diabetic mothers than in control subjects: from 103 ± 14 to 111 ± 17 ml/min (8 ± 13%) vs. from 108 ± 17 to 128 ± 23 ml/min (19 ± 7%, P = 0.009) and from 509 ± 58 to 536 ± 80 ml/min (5 ± 9%) vs. from 536 ± 114 to 620 ± 140 ml/min (16 ± 11%, P = 0.0035). Mean arterial pressure and renal vascular resistances declined less than in control subjects: 2 ± 5 vs. -2 ± 3% (P = 0.019) and 3 ± 9 vs. -14 ± 8% (P = 0.001). CONCLUSIONS: Reduced functional reserve may reflect a reduced number of nephrons undergoing individual hyperfiltration. If so, offspring of type 1 diabetic mothers may be predisposed to glomerular and vascular diseases.

Multitissue insulin resistance despite near-normoglycemic remission in Africans with ketosis-prone diabetes.

OBJECTIVE: To characterize insulin action in Africans with ketosis-prone diabetes (KPD) during remission. RESEARCH DESIGN AND METHODS: At Saint-Louis Hospital, Paris, France, 15 African patients with KPD with an average 10.5-month insulin-free near-normoglycemic remission period (mean A1C 6.2%) were compared with 17 control subjects matched for age, sex, BMI, and geographical origin. Insulin stimulation of glucose disposal, and insulin suppression of endogenous glucose production (EGP) and nonesterified fatty acids (NEFAs), was studied using a 200-min two-step (10 mU x m(-2) body surface x min(-1) and 80 mU x m(-2) x min (-1) insulin infusion rates) euglycemic clamp with [6,6-(2)H(2)]glucose as the tracer. Early-phase insulin secretion was determined during an oral glucose tolerance test. RESULTS: The total glucose disposal was reduced in patients compared with control subjects (7.5 +/- 0.8 [mean +/- SE] vs. 10.5 +/- 0.9 mg x kg(-1) x min(-1); P = 0.018). EGP rate was higher in patients than control subjects at baseline (4.0 +/- 0.3 vs. 3.0 +/- 0.1 mg x kg(-1) x min(-1); P = 0.001) and after 200-min insulin infusion (10 mU x m(-2) x min(-1): 1.6 +/- 0.2 vs. 0.6 +/- 0.1, P = 0.004; 80 mU x m(-2) x min(-1): 0.3 +/- 0.1 vs. 0 mg x kg(-1) x min(-1), P = 0.007). Basal plasma NEFA concentrations were also higher in patients (1,936.7 +/- 161.4 vs. 1,230.0 +/- 174.1 micromol/l; P = 0.002) and remained higher after 100-min 10 mU x m(-2) x min(-1) insulin infusion (706.6 +/- 96.5 vs. 381.6 +/- 55.9 micromol/l; P = 0.015). CONCLUSIONS: The triad hepatic, adipose tissue, and skeletal muscle insulin resistance is observed in patients with KPD during near-normoglycemic remission, suggesting that KPD is a form of type 2 diabetes.

Ketosis-prone type 2 diabetes mellitus and human herpesvirus 8 infection in sub-saharan africans.

CONTEXT: An atypical form of type 2 diabetes mellitus (DM-2) is revealed by ketosis (ketosis-prone type 2 diabetes mellitus), frequently occurring in individuals who are black and of African origin, and characterized by an acute onset requiring transient insulin therapy. Its sudden onset suggests precipitating factors. OBJECTIVE: To investigate the putative role of human herpesvirus 8 (HHV-8) in the pathogenesis of ketosis-prone DM-2. DESIGN, SETTING, AND PARTICIPANTS: A cross-sectional study in which antibodies were searched against latent and lytic HHV-8 antigens using immunofluorescence. The presence of HHV-8 in genomic DNA was investigated in 22 of the participants at clinical onset of diabetes. We also tested whether HHV-8 was able to infect human pancreatic beta cells in culture in vitro. The study was conducted at Saint-Louis University Hospital, Paris, France, from January 2004 to July 2005. All participants were black and of African origin: 187 were consecutive diabetic patients of whom 81 had ketosis-prone DM-2 and 106 had nonketotic DM-2, and 90 individuals were nondiabetic control participants who were matched for age and sex. MAIN OUTCOME MEASURES: Seroprevalence of HHV-8 and percentage of patients with HHV-8 viremia at onset in ketosis-prone DM-2. RESULTS: HHV-8 antibodies were found in 71 patients (87.7%) with ketosis-prone DM-2 vs 16 patients (15.1%) with nonketotic DM-2 (odds ratio, 39.9; 95% confidence interval, 17.1-93.4; P < .001) and 36 of the control participants (40.0%) (odds ratio, 10.7; 95% confidence interval, 4.9-23.4; P < .001). HHV-8 in genomic DNA was present in 6 of 13 patients with ketosis-prone DM-2 tested at acute onset and in 0 of 9 patients with nonketotic DM-2. HHV-8 proteins were present in human islet cells that were cultured for 4 days in the presence of HHV-8. CONCLUSIONS: In this preliminary cross-sectional study, the presence of HHV-8 antibodies was associated with ketosis-prone DM-2 in patients of sub-Saharan African origin. Longitudinal studies are required to understand the clinical significance of these findings.

The replacement of human insulin with insulin analogs: a survey conducted in france to determine current and recommended practice.

OBJECTIVES: To determine current and potential patterns of prescription of human insulins and insulin analogs in patients with diabetes mellitus in hospitals and general/specialist practice in France. METHODS: This was a survey of diabetologists and endocrinologists working in hospital and/or private practice in France. The clinicians answered a six-part questionnaire during a face-to-face interview at the clinician's practice regarding current and potential patterns of use of human insulin and insulin analogs. RESULTS: A total of 80 French clinicians were interviewed. The majority of clinicians prescribed insulin analogs to their diabetic patients, with human insulin being prescribed in a minority of patients. When asked their opinions on switching from a regimen involving human insulin to one involving insulin analogs, clinicians generally recommended a treatment regimen that involved very little change. Most clinicians recommended that basal insulin analogs replace NPH human insulin, rapid-acting insulin analogs replace rapid-acting (regular) human insulin, and premix insulin analogs replace human premix insulins, with little change in the recommended number of injections or the dose of the insulin. Precaution was recommended in the elderly, pregnant patients, those of certain ethnicities, and those at risk of hypoglycemia. CONCLUSION: Insulin analogs are currently prescribed by the majority of diabetologists and endocrinologists in this survey in France. When switching from a regimen involving human insulin to one involving insulin analogs, clinicians generally recommend a treatment program that involves very little change.

High prevalence of glucose-6-phosphate dehydrogenase deficiency without gene mutation suggests a novel genetic mechanism predisposing to ketosis-prone diabetes.

CONTEXT: Ketosis-prone diabetes (KPD) is mostly observed in males of West African descent and is characterized by phasic or permanent insulin dependence without apparent autoimmune process. OBJECTIVE: KPD subjects display a propensity to hyperglycemia-induced acute insulin deficiency, suggesting that they exhibit a propensity to oxidative stress in beta-cells. The enzyme glucose-6-phosphate dehydrogenase (G6PD) is a defense mechanism against oxidative stress, and G6PD deficiency, an X-linked genetic disorder with male predominance, is frequent in West Africans. We hypothesized that mutations in the G6PD gene could predispose to KPD. DESIGN: We studied G6PD erythrocyte enzyme activity and the insulin secretory reserve (glucagon-stimulated C peptide) in a cohort of hospitalized West Africans with KPD (n = 59) or type 2 diabetes (T2DM; n = 59) and in normoglycemic controls (n = 55). We also studied the G6PD gene in an extended population of KPD patients (n = 100), T2DM patients (n = 59), and controls (n = 85). RESULTS: The prevalence of G6PD deficiency was higher in KPD than in T2DM and controls (42.3%; 16.9%; 16.4%; P = 0.01). In KPD, but not in T2DM, insulin deficiency was proportional to the decreased G6PD activity (r = 0.33; P = 0.04). We found no increase in the prevalence of G6PD gene mutations in KPD compared with T2DM and controls. Rather, we found a 20.3% prevalence of G6PD deficiency in KPD without gene mutation. CONCLUSIONS: This study suggests that 1) G6PD deficiency alone is not causative of KPD; and 2) alterations in genes controlling both insulin secretion and G6PD-mediated antioxidant defenses may contribute to the predisposition to KPD in West Africans.

Biphasic insulin aspart 30: literature review of adverse events associated with treatment.

BACKGROUND: Biphasic insulin aspart 30 (BIAsp 30 [30% soluble, rapid-acting insulin aspart and 70% protamine-bound insulin aspart], NovoLog Mix 70/30, Novo Nordisk, Bagsvaerd, Denmark), a premixed insulin analogue, addresses both the prandial and basal aspects of glucose regulation when used once or twice daily in patients with type 1 or type 2 diabetes. It provides overall glycemic control similar to biphasic human insulin 30 (BHI 30, 30% human insulin and 70% neutral protamine Hagedorn [NPH] insulin) in patients with type 1 or type 2 diabetes. OBJECTIVE: The aim of this review was to evaluate the safety profile associated with BIAsp 30 in patients with type 1 or type 2 diabetes versus that of comparator insulin products, including BHI 30 and biphasic insulin lispro 25 (Mix 25 [25% biphasic insulin lispro and 75% protaminated lispro], Humalog Mix 75/25, Eli Lilly and Company, Indianapolis, Indiana), together with the basal insulins, including NPH insulin and insulin glargine (Lantus, Sanofi-Aventis Pharmaceuticals, Paris, France). METHODS: Data from human clinical studies published in peer-reviewed journals or as conference proceedings that reported safety results in patients with type 1 or type 2 diabetes who were treated with BIAsp 30 versus comparator insulins were evaluated. To locate the appropriate articles, a MEDLINE search was performed for all years up to February 2005, using the following key words: biphasic insulin aspart, BIAsp 30, biphasic insulin, and premixed insulin. Additional papers were identified by examining the reference lists in these papers as well as our own personal reference files. Results from 17 publications were analyzed. The analysis included >2600 patients with type 2 diabetes (mean [range] age, 58 [36-70] years; duration of diabetes, 11.8 [9-17] years; and baseline glycosylated hemoglobin [HbA1c], 8.6% [7.5%-9.9%]). It also included 104 patients with type 1 diabetes (mean [range] age, 44.5 [30-58] years; duration of diabetes, 16 [2-30] years; and baseline HbA1c, 8.4% [7.2%-10.4%]). RESULTS: Hypoglycemia occurred in 43% to 57% of patients receiving BIAsp 30 versus 32% to 57% of patients receiving BHI 30 and 28% of patients receiving NPH insulin. Major hypoglycemic events were uncommon in most studies; but when they did occur, they were reported less frequently in patients receiving BIAsp 30 (2%-8% of patients) than in patients receiving BHI 30 (2%-14% of patients). Furthermore, patients treated with BIAsp 30 were at lower risk of experiencing minor nocturnal hypoglycemia than patients receiving comparator insulin; in 1 study, the relative risk (BIAsp 30 vs BHI 30) was calculated to be 0.63 (95% CI, 0.37 to 1.09). The adverse event (AE) profile, weight gain during treatment, and formation of cross-reactive antibodies were not different between BIAsp 30 and BHI 30. AEs were reported in 36% to 90% of patients receiving BIAsp 30, 38% to 88% of patients receiving BHI 30, and 51% of patients receiving Mix 25. The use of oral antidiabetic drugs in combination with BIAsp 30 did not alter the safety profile of BIAsp 30. CONCLUSION: The flexible and convenient treatment regimen offered by BIAsp 30, together with its ability to improve postprandial glucose control, is associated with a safety profile comparable to that of BHI 30 and NPH insulin, with a lower risk of major and nocturnal hypoglycemic events.

PAX4 gene variations predispose to ketosis-prone diabetes.

Ketosis-prone diabetes (KPD) is a rare form of type 2 diabetes, mostly observed in subjects of west African origin (west Africans and African-Americans), characterized by fulminant and phasic insulin dependence, but lacking markers of autoimmunity observed in type 1 diabetes. PAX4 is a transcription factor essential for the development of insulin-producing pancreatic beta-cells. Recently, a missense mutation (Arg121Trp) of PAX4 has been implicated in early and insulin deficient type 2 diabetes in Japanese subjects. The phenotype similarities between KPD and Japanese carriers of Arg121Trp have prompted us to investigate the role of PAX4 in KPD. We have screened 101 KPD subjects and we have found a new variant in the PAX4 gene (Arg133Trp), specific to the population of west African ancestry, and which predisposes to KPD under a recessive model. Homozygous Arg133Trp PAX4 carriers were found in 4% of subjects with KPD but not in 355 controls or 147 subjects with common type 2 or type 1 diabetes. In vitro, the Arg133Trp variant showed a decreased transcriptional repression of target gene promoters in an alpha-TC1.6 cell line. In addition, one KPD patient was heterozygous for a rare PAX4 variant (Arg37Trp) that was not found in controls and that showed a more severe biochemical phenotype than Arg133Trp. Clinical investigation of the homozygous Arg133Trp carriers and of the Arg37Trp carrier demonstrated a more severe alteration in insulin secretory reserve, during a glucagon-stimulation test, compared to other KPD subjects. Together these data provide the first evidence that ethnic-specific gene variants may contribute to the predisposition to this particular form of diabetes and suggest that KPD, like maturity onset diabetes of the young, is a rare, phenotypically defined but genetically heterogeneous form of type 2 diabetes.

Ketosis-prone type 2 diabetes in patients of sub-Saharan African origin: clinical pathophysiology and natural history of beta-cell dysfunction and insulin resistance.

Nonautoimmune ketosis-prone diabetic syndromes are increasingly frequent in nonwhite populations. We have characterized a cohort of patients of sub-Saharan African origin who had ketosis-prone type 2 diabetes (n = 111), type 1 diabetes (n = 21), and type 2 diabetes (n = 88) and were admitted to a hospital for management of uncontrolled diabetes. We compared epidemiological, clinical, and metabolic features at diabetes onset and measured insulin secretion (glucagon-stimulated C-peptide) and insulin action (short intravenous insulin tolerance test) during a 10-year follow-up. Ketosis-prone type 2 diabetes shows a strong male predominance, stronger family history, higher age and BMI, and more severe metabolic decompensation than type 1 diabetes. In ketosis-prone type 2 diabetes, discontinuation of insulin therapy with development of remission of insulin dependence is achieved in 76% of patients (non-insulin dependent), whereas only 24% of patients remain insulin dependent. During evolution, ketosis-prone type 2 diabetes exhibit specific beta-cell dysfunction features that distinguish it from type 1 and type 2 diabetes. The clinical course of non-insulin-dependent ketosis-prone type 2 diabetes is characterized by ketotic relapses followed or not by a new remission. Progressive hyperglycemia precedes and is a strong risk factor for ketotic relapses (hazard ratio 38). The probability for non-insulin-dependent ketosis-prone type 2 diabetes to relapse is 90% within 10 years, of whom approximately 50% will become definitively insulin dependent. Insulin sensitivity is decreased in equal proportion in both ketosis-prone type 2 diabetes and type 2 diabetes, but improves significantly in non-insulin-dependent ketosis-prone type 2 diabetes, only after correction of hyperglycemia. In conclusion, ketosis-prone type 2 diabetes can be distinguished from type 1 diabetes and classical type 2 diabetes by specific features of clinical pathophysiology and also by the natural history of beta-cell dysfunction and insulin resistance reflecting a propensity to glucose toxicity.

Effect of a diabetic environment in utero on predisposition to type 2 diabetes.

BACKGROUND: Type 2 diabetes is affected by genetics and environmental factors. We aimed to assess the effect of an in-utero diabetic environment independently of the genetic background for type 2 diabetes. METHODS: We measured insulin sensitivity and insulin secretion in response to oral and intravenous glucose in 15 non-diabetic adult offspring of mothers with type 1 diabetes (exposed participants) and 16 offspring of type 1 diabetic fathers (controls). No participants had type 1 diabetes-associated autoantibodies. We also measured pancreatic polypeptide, a marker of parasympathetic drive to the pancreas. FINDINGS: There was no difference between the groups with respect to percent body fat and insulin sensitivity. Five of the 15 exposed participants, but none of the controls had impaired glucose tolerance (p=0.02). Early insulin secretion after an oral glucose tolerance test was lower in exposed participants than in controls: 8.6 IU/mmol (SD 5.4) in exposed participants with impaired glucose tolerance, 14.2 IU/mmol (6.5) in those with normal glucose tolerance and 17.7 IU/mmol (10.9) in controls (p=0.04). Mean insulin secretion rate during glucose infusion study was 4.7 pmol/kg per min (3.6) in people with impaired glucose tolerance, 5.5 pmol/kg per min (4.5) in exposed participants with normal glucose tolerance and 7.5 pmol/kg per min (6.1) in controls (p<0.0001). The area under the curve of pancreatic polypeptide 120 min after oral glucose ingestion was 1007 (429) in people with impaired glucose tolerance, 2829 (1701) in those with normal glucose tolerance, and 3224 (1352) in controls (p=0.04). INTERPRETATION: Exposure to a diabetic environment in utero is associated with increased occurrence of impaired glucose tolerance and a defective insulin secretory response in adult offspring, independent of genetic predisposition to type 2 diabetes. This insulin secretory defect could be related to low parasympathetic tone. Epidemiological studies are needed to confirm our observations before therapeutic strategies can be devised.

[Cushing's syndrome during pregnancy]. / Le syndrome de Cushing durant la grossesse.

The rare association of Cushing's syndrome and pregnancy is explained by the amenorrhea and sterility inherent to the syndrome. In the literature, 125 cases have been reported: 30 cases of early diagnosis and 95 others diagnosed in the second half of pregnancy. AT THE START OF PREGNANCY: When hypercorticism exists before pregnancy it is hardly secretory. Its diagnosis, at an early stage, is not hindered by the hormone modifications of pregnancy. Its aetiological treatment raises the problem of the compatibility in pursuing the latter. IN THE SECOND HALF OF PREGNANCY: The positive and aetiological diagnoses of Cushing's syndrome are difficult and its prevalence may therefore be underestimated. The evocative clinical signs are unspecific: excessive weight gain, hypertension of pregnancy and gestational diabetes. The 24-hour free hypercortisoluria and the absence of dexamethasone inhibition are of little diagnostic value after the 14th week of amenorrhea. The positive diagnosis therefore relies essentially on the abolition of the circadian rhythm of cortisol. The biological hyperandrogenia commonly observed is not discriminating. Adrenal aetiologies are frequent. Imaging must be performed to eliminate an adrenocortical tumor. PROGNOSIS: The maternal prognosis depends on the hypertension, preeclampsia, diabetes and the complications of Cushing's syndrome. It depends on the activity of the hypercorticism and its early aetiological treatment, which must not be delayed after pregnancy. The foetal prognosis depends on the maternal prognosis. It is represented by preterm delivery, hypotrophy and death of the foetus in utero. The therapeutic management must be symptomatic and aetiologic, maternal and obstetrical.

Novel mutations in CYP21 detected in individuals with hyperandrogenism.

We studied the functional and structural consequences of two novel missense mutations in CYP21 found in women with hyperandrogenism. The women were predicted to carry mutations by hormonal evaluation, but did not display any of the genotypes commonly associated with congenital adrenal hyperplasia. In one woman the novel mutation V304M was found in homozygous form. After expression in COS-1 cells the mutated enzyme was found to have a residual activity of 46% for conversion of 17-hydroxyprogesterone and 26% for conversion of progesterone compared with the normal enzyme. The V304M variant thus represents the sixth known missense mutation associated with nonclassical disease. A normal degradation pattern for this mutant enzyme indicates that the missense mutation is of functional, rather than structural, importance. The other mutation, G375S, was detected in a young woman with signs of hyperandrogenism, in heterozygous form together with P453S, a mutation known to cause nonclassical congenital adrenal hyperplasia (her genotype was G375S+P453S/wild type). This novel variant almost completely abolished enzyme activity; conversion was 1.6% and 0.7% of normal for 17-hydroxyprogesterone and progesterone, respectively. These results underline the importance of genetic evaluation and counseling in hyperandrogenic women who are predicted to carry congenital adrenal hyperplasia-causing mutations by biochemical tests. It also supports the idea that the heterozygous carrier state for CYP21 mutations can be associated with symptoms of androgen excess in certain susceptible individuals.