Short-term treatment with a gonadotropin-releasing hormone antagonist, cetrorelix, in rheumatoid arthritis (AGRA): a randomized, double-blind, placebo-controlled study.

OBJECTIVES: Gonadotropin-releasing hormone (GnRH) stimulates immune responses; therefore, antagonizing GnRH with cetrorelix may have anti-inflammatory effects. The aim of this study was to assess short-term cetrorelix therapy in rheumatoid arthritis (RA) patients. METHOD: In this proof-of-concept, randomized, double-blind study involving 99 patients with active, long-standing RA, 48 patients received subcutaneous cetrorelix (5 mg/day on days 1 and 2; 3 mg/day on days 3-5) and 51 received placebo. The primary end-point was the change in the 28-joint Disease Activity Score based on C-reactive protein (DAS28-CRP) by day 5, when the greatest GnRH suppression was anticipated. Secondary end-points included the change in tumour necrosis factor (TNF)-α, and achievement of American College of Rheumatology (ACR) responses and DAS28-CRP < 2.6 by day 5. Patients were followed up on days 10 and 15. RESULTS: By day 5, DAS28-CRP was non-significantly reduced by 0.82 in the cetrorelix group compared to a 0.57 reduction in the placebo group (p = 0.091), TNF-α (log pg/mL) was significantly reduced in the cetrorelix group compared with the placebo group [0.55, 95% confidence interval (CI) 0.08-1.01, p = 0.023], and more patients on cetrorelix achieved ACR20 responses (40% vs. 18%, p = 0.015) and DAS28-CRP < 2.6 (13% vs. 0%, p = 0.009). Inflammatory markers increased towards baseline levels after withdrawal of treatment. Rates of adverse events were similar in both groups. CONCLUSIONS: Although there was no significant difference in the primary end-point between groups, antagonizing GnRH led to significant improvements in key secondary end-points. Thus, GnRH antagonists may have rapid anti-inflammatory effects in RA, already occurring within 5 days. The data suggest a novel mode of action for TNF-α inhibition in RA, and potentially in other autoimmune diseases.

Reduced soluble receptor for advanced glycation end-products (sRAGE) scavenger capacity precedes pre-eclampsia in Type 1 diabetes.

OBJECTIVE: Increased advanced glycation end-products (AGEs) and their soluble receptors (sRAGE) have been implicated in the pathogenesis of pre-eclampsia (PE). However, this association has not been elucidated in pregnancies complicated by diabetes. We aimed to investigate the serum levels of these factors in pregnant women with Type 1 diabetes mellitus (T1DM), a condition associated with a four-fold increase in PE. DESIGN: Prospective study in women with T1DM at 12.2 ± 1.9, 21.6 ± 1.5 and 31.5 ± 1.7 weeks of gestation [mean ± standard deviation (SD); no overlap] before PE onset. SETTING: Antenatal clinics. POPULATION: Pregnant women with T1DM (n = 118; 26 developed PE) and healthy nondiabetic pregnant controls (n = 21). METHODS: Maternal serum levels of sRAGE (total circulating pool), N(ε)-(carboxymethyl)lysine (CML), hydroimidazolone (methylglyoxal-modified proteins) and total AGEs were measured by immunoassays. MAIN OUTCOME MEASURES: Serum sRAGE and AGEs in pregnant women with T1DM who subsequently developed PE (DM PE+) versus those who remained normotensive (DM PE-). RESULTS: In DM PE+ versus DM PE-, sRAGE was significantly lower in the first and second trimesters, prior to the clinical manifestation of PE (P < 0.05). Further, reflecting the net sRAGE scavenger capacity, sRAGE:hydroimidazolone was significantly lower in the second trimester (P < 0.05) and sRAGE:AGE and sRAGE:CML tended to be lower in the first trimester (P < 0.1) in women with T1DM who subsequently developed PE versus those who did not. These conclusions persisted after adjusting for prandial status, glycated haemoglobin (HbA1c), duration of diabetes, parity and mean arterial pressure as covariates. CONCLUSIONS: In the early stages of pregnancy, lower circulating sRAGE levels, and the ratio of sRAGE to AGEs, may be associated with the subsequent development of PE in women with T1DM.

The effect of high-dose vitamin D on bone mineral density and bone turnover markers in postmenopausal women with low bone mass--a randomized controlled 1-year trial.

UNLABELLED: Vitamin D is widely used in osteoporosis treatment, although the optimal dose is not known. This 1-year clinical study among 297 women aged 50-80 years old showed that a vitamin D(3) dose of 6,500 IU/day was not better than the standard dose of 800 IU/day in improving bone mineral density (BMD) in the hip and spine. INTRODUCTION: The purpose of this study was to determine whether a high dose of vitamin D(3) was better than the standard dose in improving BMD and reducing bone turnover in postmenopausal women with reduced bone mass. METHODS: The study was a 1-year randomized double-blind controlled trial comparing high-dose vitamin D(3) with the standard dose. Postmenopausal women (n = 297) with a BMD T-score ≤ -2.0 in either lumbar spine (L2-4) or total hip were included and randomized to 6,500 IU vitamin D(3)/day (20,000 IU twice per week + 800 IU/day) or 800 IU vitamin D(3)/day (placebo twice per week + 800 IU/day). Both groups were given 1,000 mg elemental calcium/day. The primary endpoint was a change in BMD in total hip and lumbar spine (L2-4). RESULTS: After 1 year, serum 25-hydroxyvitamin D (25(OH)D) increased [mean (SD)] from 71 (23) to 185 (34) nmol/l and from 71 (22) to 89 (17) nmol/l in the high- and standard-dose vitamin D groups, respectively. BMD at all measurement sites was unchanged or slightly improved with no significant differences between the groups. Although bone turnover was reduced in both groups, the more pronounced reduction in serum levels of the bone formation marker P1NP in the standard-dose group may indicate that this treatment was more efficient. Adverse events did not differ between the groups. CONCLUSIONS: One year treatment with 6,500 IU vitamin D(3)/day was not better than 800 IU/day regarding BMD in vitamin D-replete postmenopausal women with reduced bone mass and was less efficient in reducing bone turnover.

The association of luteinizing hormone and follicle-stimulating hormone with cytokines and markers of disease activity in rheumatoid arthritis: a case-control study.

OBJECTIVES: Disease activity in rheumatoid arthritis (RA) varies substantially during periods when luteinizing hormone (LH) and follicle-stimulating hormone (FSH) levels change, for example during pregnancy, postpartum, and menopause. We wanted to investigate whether small fluctuations in these hormones could be associated with similar fluctuations in cytokines and disease activity in RA. METHODS: Disease activity markers, serum LH, FSH, and 24 cytokines were assessed on days 1 and 8 in 20 RA patients (median age 58 years, six males) and 19 controls (median age 56 years, six males). RESULTS: Percentage changes in LH and FSH correlated positively with percentage changes in key proinflammatory cytokines such as tumour necrosis factor (TNF)alpha (LH r = 0.737, p = 0.0007; FSH r = 0.680, p = 0.001) and interleukin (IL)-1beta (LH r = 0.515, p = 0.050; FSH r = 0.749, p = 0.0008). Similar correlations were observed with IL-2, IL-2R, IL-8, monocyte chemoattractant protein (MCP)-1, macrophage inflammatory protein (MIP)-1alpha, MIP-1beta, and eotaxin, but not with the anti-inflammatory cytokine IL-10, in RA and not in controls. Percentage changes in LH, FSH, and cytokines were not correlated with percentage changes of several disease activity markers but were correlated positively with cross-sectional levels of disease activity markers [erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), Visual Analogue Scale (VAS) pain, VAS global (physician/patient), and the modified Health Assessment Questionnaire (MHAQ)]. CONCLUSIONS: The significant associations between percentage changes in LH and FSH and percentage changes in key cytokines and several cross-sectional markers of disease activity may indicate that LH and FSH influence crucial points of the cytokine cascade in RA. This may help to explain, partially, why disease activity initiates or worsens during periods of increased LH and FSH, such as the postpartum period and the menopause.

Efficient isolation of the subunits of recombinant and pituitary glycoprotein hormones.

Complete dissociation into subunits was attained by incubating Chinese hamster ovary (CHO)-derived or native human thyrotropin, follitropin and lutropin overnight at 37 degrees C in acetic acid. The alpha-and beta-subunits of the pituitary glycoprotein hormones were rapidly and quantitatively isolated by reversed-phase high-performance liquid chromatography (RP-HPLC). A dissociation efficiency of > 98% was obtained on the basis of mass determinations of the heterodimers and subunits carried out via mass spectrometry. CHO-derived or native subunits were isolated on a C4 column (80-90% total recovery) and characterized comparatively for purity, hydrophobicity, molecular mass and charge distribution by HPLC, mass spectrometry, sodium dodecylsulfate-polyacrylamide gel electrophoresis and isoelectric focusing. Thyrotropin was used as a model for showing that, after subunit reassociation, the in vivo bioactivity of the hormone was completely restored. The method described is mild, practical, flexible, and can be adapted to dissociate microgram amounts of native or recombinant glycoprotein hormones, allowing characterization of each subunit.

Decreased levels of testosterone and gonadotrophins in men with long-standing tetraplegia.

STUDY DESIGN: Blood samples were frequently collected during a 24-h period from six tetraplegic men. The results were compared with those of eight able-bodied controls. OBJECTIVE: Previous studies have reported conflicting results regarding the plasma concentrations of testosterone, luteinizing hormone (LH) and follicle-stimulating hormone (FSH) in tetraplegia. The objective of this study was to examine the pituitary-gonadal axis by determining the plasma concentrations and circadian variations of these hormones in men with long-standing tetraplegia. SETTING: Sunnaas Hospital, Norway. METHODS: The plasma concentrations of hormones were measured with standardized assays. RESULTS: All three hormones and free testosterone index were decreased in the tetraplegic subjects compared with the able-bodied controls (P<0.05). We also determined the morning levels of hormones with regulatory effects on testosterone, LH and FSH. Whereas plasma leptin was significantly higher in the tetraplegic group, no significant differences in the morning plasma values for insulin, SHBG, GH or IGF-1, or in the 24-h urine concentrations of cortisol were detected between the two groups. The plasma concentration of LH displayed a circadian variation (P<0.05) in the tetraplegic group, but not among the able-bodied. No circadian variation was noted for the plasma concentrations of testosterone and FSH in either group. CONCLUSION: Our data indicate that, over time, tetraplegic male subjects might be at risk of developing hypogonadism.

Biochemical characterization of four novel mutations in the thyroid hormone receptor beta gene in patients with resistance to thyroid hormone.

In resistance to thyroid hormone (RTH), decreased tissue responsiveness to thyroid hormones is usually caused by mutations in the thyroid hormone receptor beta (THRB) gene. Subsequently, in serum the level of thyroid stimulating hormone (TSH) is not suppressed despite increased concentrations of thyroxine (T4) and triiodothyronine (T3). In our laboratory, DNA sequences of exon 7 to 10 in the THRB gene have been analysed in individuals with biochemical signs of RTH. Four novel point mutations were identified (I250T, A279E, T327A and L440P) and their effects on T3 binding activity characterized. The mutations were introduced into a vector carrying the wild-type THRB cDNA by in vitro mutagenesis. T3-binding activity was measured by a filter-binding assay procedure in receptors generated from the vector by in vitro transcription and translation. Specific binding was calculated as total activity subtracted by non-specific activity. The association constants (Ka) of the wildtype (WT) and mutant receptors were determined by Scatchard analysis. No specific T3-binding was observed for the receptor with the A279E mutation. The binding affinity was reduced by 74% in the T327A mutant and by about 50% in the I250T and L440P mutants compared to the WT receptor (Ka = 4.2 x 10(10) L/mol). The reduction of T3-binding affinity caused by the four mutations in our study is comparable to the effects of THRB gene mutations found in other patients with RTH and supports the assumption that the signs of RTH observed in our patients are caused by the mutations.

Increased serum levels of advanced glycation endproducts predict total, cardiovascular and coronary mortality in women with type 2 diabetes: a population-based 18 year follow-up study.

AIMS/HYPOTHESIS: AGEs, modification products formed by glycation or glycoxidation of proteins and lipids, have been linked to premature atherosclerosis in patients with diabetes. We investigated whether increased serum levels of AGEs predict total, cardiovascular (CVD) or CHD mortality in a population-based study. SUBJECTS AND METHODS: Serum levels of AGEs were determined by immunoassay in a random sample of 874 Finnish diabetic study participants (488 men, 386 women), aged 45-64 years. These participants were followed for 18 years for total, CVD and CHD mortality. RESULTS: Multivariate Cox regression models revealed that serum levels of AGEs were significantly associated with total (p = 0.002) and CVD mortality (p = 0.021) in women, but not in men. Serum levels of AGEs in the highest sex-specific quartile predicted all-cause (hazards ratio [HR] 1.51; 95% confidence intervals [CI], 1.14-1.99; p = 0.004), CVD (HR 1.56; 95% CI 1.12-2.19; p = 0.009), and CHD (HR 1.68; 95% CI 1.11-2.52; p = 0.013) mortality in women, even after adjustment for confounding factors, including high-sensitivity C-reactive protein. CONCLUSIONS/INTERPRETATION: Increased serum levels of AGEs predict total and CVD mortality in women with type 2 diabetes.

Blood glucose lowering by means of lifestyle intervention has different effects on adipokines as compared with insulin treatment in subjects with type 2 diabetes.

AIMS/HYPOTHESIS: Adipokines may be important in mediating signals from adipocytes to insulin-sensitive tissue and vasculature. We studied the effect of different glucose-lowering therapies on serum levels of plasminogen activator inhibitor-1 (PAI-1), high-sensitivity C-reactive protein (hs-CRP), TNF-alpha, leptin, adiponectin and ghrelin in patients with type 2 diabetes. SUBJECTS AND METHODS: Twenty-eight patients with poorly controlled type 2 diabetes who were receiving oral hypoglycaemic agents were allocated to one of the following groups, and treated for 1 year: (1) lifestyle intervention (L); (2) insulin treatment (I); and (3) combined treatment (L+I). RESULTS: Similar improvements in glycaemic control occurred in all three groups. There was a reduction in body weight of 3.0 kg (median) (95% CI -5.9 to -2.0) in group L, whereas in groups L+I and I body weight increased by 3.5 kg (95% CI 1.5-4.9) and 4.9 kg (95% CI -3.1 to 8.2), respectively. By trend analyses, group L had reduced levels of PAI-1 (p=0.002), hs-CRP (p<0.0001) and TNF-alpha (p=0.006), while no significant changes were observed in the levels of leptin or adiponectin. In group I, the median levels of PAI-1 (p=0.008), TNF-alpha (p=0.058) and leptin (p=0.004) increased. In the L+I group there was a reduction in PAI-1 levels (p=0.014) and an increase in levels of leptin (p<0.001). The differences in changes in the levels of PAI-1, hs-CRP, TNF-alpha and leptin between groups were also significant (all p<0.01). CONCLUSIONS/INTERPRETATION: Improvement of glycaemic control through lifestyle intervention in type 2 diabetes had more beneficial effects on adipokine levels than when the same lowering of HbA(1c) was achieved with insulin treatment.

Time course of specific AGEs during optimised glycaemic control in type 2 diabetes.

BACKGROUND: Several advanced glycation endproducts (AGEs) are formed in the hyperglycaemic state. Although serum AGEs correlate with average glycaemic control in patients with type 2 diabetes and predict the development of complications, it is not known how serum AGEs change during optimisation of diabetes therapy. METHODS: We evaluated the change in serum levels of total AGE and the AGEs CML (Nepsilon-carboxymethyllysine) and MGHI (methylglyoxal-derived hydroimidazolone), as well as markers of endothelial function in 28 subjects with type 2 diabetes, who were poorly controlled on oral agents,before and after the institution of insulin therapy. RESULTS: Mean subject age (+/- SEM) was 58 +/- 2 years,body mass index 27.7 +/- 0.8 kg/m2, and known duration of diabetes was 8.1 +/- 0.9 years. With insulin treatment fasting blood glucose levels dropped from 12.1 +/- 0.9 mmol/l to 6.9 +/- 0.3 and 8.1 +/- 0.4 mmol/l after three and six months, respectively (both p<0.001), while HbA1c decreased from 10.0 +/- 0.3 to 7.8 +/- 0.2% (p<0.001). Endothelial function improved as indicated by a small but significant decrease in soluble intercellular cell adhesion molecule (sICAM-1) (152 +/- 10 to 143 +/- 8 ng/ml, p<0.02)and sE-selectin (111 +/- 16 to 102 +/-12 ng/ml, p<0.02)levels. In contrast, we observed only a tendency towards a decrease in CML levels (110 +/-22 to 86 +/- 13 microg/mg protein, p=ns), but a small increase of MGHI (from 0.23 +/- 0.02 to 0.29 +/- 0.04 U/mg protein, p<0.02). At baseline, 16 patients were on metformin, which is known to reduce methylglyoxal levels and reduce generation of reactive oxygen species. They had similar levels of CML and MGHI to the 12 non-metformin users, although their HbA1c was lower (9.4 +/- 0.3 vs 10.7 +/- 0.6 %). During insulin, patients receiving concomitant metformin therapy showed a similar course of CML and MGHI to those not taking metformin. CONCLUSION: Although insulin therapy improved HbA1c and markers of endothelial function, the levels of serum AGEs did not follow the same time course. This suggests that these specific AGEs are influenced by other factors in addition to overall glycaemia, such as oxidative stress.

Increased serum levels of the specific AGE-compound methylglyoxal-derived hydroimidazolone in patients with type 2 diabetes.

A time-delayed fluorescence immunoassay was developed for the determination of serum levels of methylglyoxal (MG)-derived hydroimidazolone using a monoclonal antiserum raised against Nalpha-acetyl-Ndelta-(5-hydro-5-methyl)-4-imidazolone, Europium-labeled anti-mouse IgG antiserum as indicator, and MG modified bovine serum albumin (BSA) as standard. Serum levels of hydroimidazolone were measured in 45 patients with type 2 diabetes aged 59.4 +/- 6.1 (mean +/- SD) years and with duration of diabetes of 7.3 +/- 3.1 years, and in 19 nondiabetic controls aged 56.3 +/- 4.3 years. The serum levels of hydroimidazolone were significantly higher in patients compared to controls: median, 3.0 (5-95 percentile, 1.6 to 5.4) U/mg protein versus 1.9 (1.2 to 2.8) U/mg protein (P =.0005). Significant positive correlations were observed between the serum levels of hydroimidazolone and serum levels of advanced glycation end products (AGEs), measured with a polyclonal anti-AGE antibody: r = 0.59 for patients (P <.0001), and r = 0.65 for controls (P =.002). Similarly, significant correlations were also found between serum levels of hydroimidazolone and N(epsilon)-(carboxymethyl)-lysine (CML): r = 0.36 in patients and r = 0.55 for controls (both P =.02). Serum hydroimidazolone levels did not correlate with fasting plasma glucose or hemoglobin A(1c) (HbA(1c)) levels. The observed differences between patients with diabetes and nondiabetic controls seem to be comparable to differences measured for other AGE compounds.

Heterogeneity of non-insulin-dependent diabetes expressed as variability in insulin sensitivity, beta-cell function and cardiovascular risk profile.

AIMS: The present study investigated the variability in insulin sensitivity and beta-cell function and their relationship to anti-glutamic acid decarboxylase (GAD) positivity and the metabolic syndrome in a group of patients with non-insulin-dependent diabetes mellitus (NIDDM). METHODS: Fifty-four subjects aged 59.5 +/- 6.1 (mean +/- SD) years with NIDDM for 7.9 +/- 3.9 years referred to hospital due to poor glycaemic control, were investigated. Insulin sensitivity was determined by the euglycaemic hyperinsulinaemic glucose clamp technique as the glucose disposal rate relative to the insulin level obtained (GDRI), and also estimated with the homeostasis model assessment (HOMA-S). beta-cell function was measured by assaying the fasting and glucagon-stimulated C-peptide levels and with the HOMA-B. RESULTS: The insulin sensitivity varied 18-fold between subjects when estimated with the clamp and six-fold when estimated with HOMA-S, and was lower the more criteria for the metabolic syndrome present (P = 0.0001 by anova). The beta-cell function varied four-fold when measured as stimulated C-peptide, and eight-fold when estimated with the HOMA-B. The levels of fasting C-peptide and HOMA-B values tended to be lower in anti-GAD+ (n = 11) than in anti-GAD-subjects (P = 0.06 and P = 0.08, respectively). From previously published coronary risk charts, we estimated the 10-year risk of a coronary heart disease (CHD) event to be > 20% in 17 of 39 patients free from cardiovascular disease at the time of study, 16 of whom qualified for a diagnosis of the metabolic syndrome. CONCLUSIONS: The wide variations in insulin sensitivity and beta-cell function found among subjects with NIDDM support the notion that the disorder is highly heterogeneous. Reduced insulin sensitivity was clearly related to the metabolic syndrome and an increased risk for CHD.

Prenatal exposure to corticosterone impairs embryonic development and increases fluctuating asymmetry in chickens (Gallus gallus domesticus).

1. The level of corticosterone in fertilised eggs from hens (Gallus gallus domesticus) was manipulated experimentally to elucidate whether stress in laying hens is harmful to the chicks, as manifested by impaired survival and reduced growth, and whether bilateral asymmetry may represent an indicator of environmental stress in poultry. 2. Three hundred and fifty eggs were randomly divided into 4 groups; 1. untreated, 2. control, 3. 10 ng corticosterone/ml and 4. 20 ng corticosterone/ml. Each of the eggs in groups 2, 3 and 4 were injected with 100 microl ethanol-saline solution (25% ethanol in saline) containing 0, 0.6 and 1.2 microg corticosterone, respectively. After the injections, the final concentration of ethanol in the egg (albumen and yolk) was 0.03%, and the concentration of added corticosterone was 0, 10 and 20 ng/ml, respectively, in groups 2, 3 and 4. All the eggs were treated on developmental d 1. 3. Corticosterone injections resulted in greater embryonic mortality, earlier termination of foetal development and reduced growth. Moreover, chicks developing in eggs with an elevated concentration of corticosterone displayed reduced developmental stability as evidenced by increased fluctuating asymmetry (FA) in tarsus length. 4. In conclusion, an increased concentration of corticosterone in the egg was detrimental to survival and growth of the chicks. Prenatal stress also generated bilateral asymmetry, and illustrates the potential application of FA as an indicator of environmental stress in poultry.

[Genetic and immunologic risks for development of type 1 diabetes--experiences from an intervention trial]. / Genetisk og immunologisk risiko for type 1-diabetes--erfaringer fra en intervensjonsstudie. Norsk studiegruppe for barnediabetes.

BACKGROUND: Type 1 diabetes is a common multi-factorial disease. Recently, promising attempts have been made at preventing the disease in individuals at risk. We present our experiences as participants in an international multicentre intervention trial, the European Nicotinamide Diabetes Intervention Trial (ENDIT). The aim is to prevent prediabetic individuals from becoming overtly diabetic by the use of nicotinamide. MATERIAL AND METHODS: First degree relatives of type 1 diabetes children attending paediatric clinics in Norway were recruited. The level of islet cell antibodies (ICA) was determined. Individuals with ICA titer above 20 Juvenile Diabetes Foundation Units (JDFU) were allocated to treatment with nicotinamide or placebo in a double-blind design. In the Norwegian patients in the trial HLA-DQ genotypes were also determined. RESULTS: 56 individuals had ICA > 20 JDFU; 36 agreed to participate in the trial. Assessment of genetic and immunological risk did not seem to emotionally upset the majority of participants; so far, no serious adverse events have been observed. The final results of this trial are expected in year 2003. INTERPRETATION: Prevention of type 1 diabetes may be feasible in the future.

Serum levels of advanced glycation end products are associated with left ventricular diastolic function in patients with type 1 diabetes.

OBJECTIVE: Impairment of left ventricular diastolic function, possibly caused by increased collagen cross-linking of the cardiac muscle, is common in patients with type 1 diabetes even without coronary artery disease. Advanced glycation end products (AGEs) cross-link tissue collagen and are found within myocardial fibers. The aim of this study was to examine for a possible association between circulating AGEs and left ventricular cardiac function. RESEARCH DESIGN AND METHODS: Left ventricular diastolic and systolic function were assessed by M-mode and Doppler echocardiography in 52 patients with type 1 diabetes, age 40 +/- 13 (mean +/- SD) years, diabetes duration 17 +/- 13 years, and HbA1c 8.3 +/- 1.1%. Serum levels of AGEs and N epsilon-(carboxymethyl)lysine (CML) were measured by newly developed competitive immunoassays. RESULTS: A positive correlation was found between serum levels of AGEs and isovolumetric relaxation time (IVRT), r = 0.46 (P < 0.0008), and left ventricular diameter during diastole, r = 0.37 (P < 0.008). The systolic parameters did not correlate with serum levels of AGEs. Stepwise regression analysis showed that 21% of the IVRT variation could be explained by serum levels of AGEs (F = 11.4, P < 0.002), whereas serum levels of CML, HbA1c, albumin excretion rate, diabetes duration, and mean arterial blood pressure were of no importance. AGE levels were significantly increased in men compared with women (P < 0.03) and present or former smokers (P < 0.04). CONCLUSIONS: Increased serum levels of AGEs, unlike serum levels of CML, are associated with heart stiffness in patients with type 1 diabetes, possibly mediated by the cross-linking properties of AGEs.

The advanced glycation end product Nepsilon-(carboxymethyl)lysine is increased in serum from children and adolescents with type 1 diabetes.

OBJECTIVE: To investigate whether children and adolescents with type 1 diabetes have increased serum levels of the glycoxidation product Nepsilon-(carboxymethyl)lysine (CML) at an early stage of the disease. RESEARCH DESIGN AND METHODS: The serum levels of CML in 38 patients with type 1 diabetes aged 14+/-3.2 (mean+/-SD) years were compared with those in 26 control subjects aged 16+/-1.7 years. The mean duration of diabetes was 5+/-4.7 years, ranging from 0.5 to 15 years. The mean levels of HbA1c were 10.3+/-2.5% in the patient group. The serum levels of CML were measured using a monoclonal anti-CML antibody in a fluoremetric immunoassay. Serum protein levels of advanced glycation end products (AGEs) were assayed using a polyclonal antibody from rabbit immunized with AGE-RNase (pAGE). RESULTS: The serum levels of CML and pAGE were significantly increased in the patient group versus the control group: 1.08 (0.45-2.97) U/ml CML (median 10-90 percentiles) vs. 0.70 (0.36-1.79) U/ml CML, P < 0.03, and 6.6 (5.1-9.9) U/ml pAGE vs. 5.5 (3.7-8.2) U/ml AGEs, P < 0.01. A significant relationship between CML and pAGE was found in the IDDM group, r = 0.76, P < 0.001. The CML levels were not associated with the HbAlc levels (n = 23, r = -0.02, NS), cholesterol levels (n = 21, r = 0.07, NS), age, sex, or diabetes duration. CONCLUSIONS: Serum levels of CML are increased in patients with type 1 diabetes. This increase precedes the development of micro- and macrovascular complications.

[Thyroid hormone resistance. Clinical, biochemical and genetic study of a family]. / Thyreoideahormonresistens. Klinisk, biokjemisk og genetisk utredning av en familie.

We here present a family where three individuals in three generations had varying degrees of goiter, tachycardia, fatigue, hyperactivity, and learning disability. Serum T3 and free T4 were elevated, whereas TSH was normal or slightly increased. The clinical findings in combination with the hormone values led to several supplementary investigations and therapies being carried out, but they had no beneficial influence on the patients' symptoms. The commonest form of thyroid hormone resistance (RTH) is an autosomal dominantly inherited disorder with varying degrees of hypo- and hyperthyroidism, including the hormonal changes described above. Several mutations, particularly in exons 9 and 10 of the thyroid hormone receptor beta gene, have been described and shown to be responsible for RTH. Exons 7, 8, 9, and 10 in the thyroid hormone receptor beta gene were amplified by polymerase chain reaction and analyzed by DNA sequencing. A heterozygous point mutation in nucleotide 1244 in exon 9 was demonstrated in the two patients with RTH that were available for the study. The guanidine to thymidine point mutation changed the codon for arginine in position 320 in the receptor protein to leucine. This mutation has previously been shown to decrease receptor affinity for T3; it has been demonstrated in some patients with RTH, and it is probably the cause of RTH in the family described in this study.

Advanced glycation end products in serum predict changes in the kidney morphology of patients with insulin-dependent diabetes mellitus.

The biochemical mechanisms that cause the development and progression of diabetic nephropathy are unknown. Advanced glycation end products (AGEs) might play a role, as shown by increased levels of tissue-bound and circulating AGEs that correlate with the severity of diabetic nephropathy. The aim of the present study was to investigate if circulating AGEs predict the progression of morphological pathology in patients with diabetic nephropathy. We have developed an immunoassay to determine serum levels of AGEs. In a prospective clinical trial of young insulin-dependent diabetes mellitus (IDDM) patients with microalbuminuria, kidney biopsies were taken at baseline and after 24 to 36 months. The biopsies were analyzed for structural changes in the glomeruli by quantitative morphometry (electron microscopy). We have retrospectively analyzed serum AGEs. The mean serum level of AGEs at the start of the study was 18.7 U/mL (95% confidence interval [CI], 16.9 to 20.5). A positive correlation between serum AGE levels at the start of study and changes from baseline to follow-up study in basement membrane thickness (r = .56, P < .02) and matrix/glomerular volume fraction (r = .57, P < .02) was demonstrated. In a stepwise regression analysis with changes in the matrix/glomerular volume fraction as the dependent variable, serum AGE levels at the start of the study proved to be a significant independent variable (P < .02), whereas the mean hemoglobin A1c (HbA1c) or HbA1c at the start was not. This study shows that serum AGEs predict the progression of early morphological kidney damage during 2.5 years in patients with IDDM.

Increased serum levels of advanced glycation end products (AGEs) in children and adolescents with IDDM.

OBJECTIVE: To investigate whether the serum levels of advanced glycation end products (AGEs) are increased in IDDM children and adolescents and to study the effect of puberty on serum levels of AGEs (S-AGEs). RESEARCH DESIGN AND METHODS: A total of 68 children and adolescent IDDM patients (age, 13.3 +/- 4.0 years; duration of diabetes, 5.0 +/- 3.6 years; HbA1c, 8.2 +/- 2.0%; Tanner stage [public hair], 1 vs. 2-5, 24/42) recruited from the pediatric outpatient clinic at Aker University Hospital were compared with 25 healthy nondiabetic control subjects. S-AGEs were measured by a fluoremetric immunoassay. RESULTS: S-AGEs were significantly elevated in the diabetic group when compared with the control group (14.4 +/- 3.5 vs. 11.7 +/- 3.0 U/ml, P < 0.002). A significant correlation (r = 0.26, P < 0.04) was found between S-AGEs and HbA1c in the diabetic group but not in the control group. No significant correlation was found between S-AGEs and the duration of diabetes in the diabetic group or S-AGEs and blood glucose concentration or age in either group. We found no difference between S-AGEs in boys and girls and in prepubertal and pubertal diabetic or control subjects. CONCLUSIONS: S-AGEs are increased in young patients with diabetes before puberty. Since AGEs are linked to the pathogenesis of vascular complications, this observation suggests that the pathological processes leading to diabetic late complications start even before puberty.

Characterization of the 5'-flanking region of the gene for the cAMP-inducible protein kinase A subunit, RIIbeta, in Sertoli cells.

Activation of cyclic AMP-dependent protein kinases (protein kinase A, PKA) by gonadotropins and cyclic AMP (cAMP) plays an important role in the regulation of testicular functions. A regulatory subunit, RIIbeta, of PKA is transcriptionally induced in rat Sertoli cells in response to treatment with cAMP. The present study addresses regulatory mechanisms leading to increased transcription of the rat RIIbeta gene. We have localized a footprint which overlaps one of the major transcription initiation sites in the basal promoter (-293 to -123). One of the proteins binding this sequence belongs to the NF-1 family of transcription factors. We also observed binding to a basic helix-loop-helix (bHLH) response element. Furthermore, transfection studies of various 5'-deletions of the rat RIIbeta gene in primary cultures of rat Sertoli cells and in peritubular cells revealed the presence of an upstream region (-723 to -395, cAMP-responsive region) inhibiting basal expression from the rat RIIbeta gene only in Sertoli cells. This region was found to enhance cAMP responsiveness in Sertoli cells but not in peritubular cells. Interactions with downstream elements seemed to be important for the function of the cAMP-responsive region. Although some short stretches reveal homology to the cAMP-responsive regions of other slowly cAMP-responding genes, and an AP-1-like element is present, no strong resemblance to any known regulatory element responsive to cAMP is found.