Ligature-associated bacterial profiles are linked to type 2 diabetes mellitus in a rat model and influenced by antibody treatment against TNF-α or RAGE.

There is a bidirectional relationship between periodontal disease (PD) and type 2 diabetes mellitus (T2D). T2D may lead to ecological perturbations in the oral environment, which may facilitate an altered microbiota. However, previous studies have been inconclusive in determining the effect of T2D on oral bacterial profiles. Therefore, we aimed to evaluate the influence of T2D on the ligature-associated bacterial profile in a diabetic rat model with PD and investigated the impact of blocking inflammatory pathways with antibodies targeting either Tumor Necrosis Factor α (TNF-α) or the receptor of advanced glycation end-products (RAGE). A total of 62 Zucker obese rats (45 T2D) and 17 lean (non-T2D) were divided into 4 treatment groups; lean with PD, obese with PD, obese with PD and anti-TNF-α treatment, and obese with PD with anti-RAGE treatment. Periodontal disease was ligature induced. Ligature-associated bacterial profiles were analyzed using Human Oral Microbe Identification Microarray (HOMIM). Ligature-associated bacterial profiles differed between lean and obese rats. Furthermore, treatment with antibodies against TNF-α or RAGE had an impact on subgingival bacterial profiles. T2D phenotypes are associated with different ligature-associated bacterial profiles and influenced by treatment with antibodies against TNF-α or RAGE.

Blockade of RAGE in Zucker obese rats with experimental periodontitis.

BACKGROUND AND OBJECTIVE: Periodontitis and type 2 diabetes mellitus (T2D) are two interrelated chronic diseases. Periodontitis is more prevalent in patients with T2D than in healthy subjects, and studies indicate that periodontitis impacts the metabolic control of patients with T2D. Hyperglycemia in T2D leads to the formation of advanced glycation end-products (AGEs). Binding of AGEs to the receptor of AGE (RAGE) elicits an increased inflammatory response that may be a key modulator linking the two diseases. The present study aimed to elucidate the effect of blocking the RAGE on the interrelationship between periodontitis and T2D in a rat model of both diseases. MATERIAL AND METHODS: Zucker obese rats (HsdHlr:ZUCKER-Lepr fa/fa ) and their lean littermates were divided into five treatment groups, with and without periodontitis. Monoclonal anti-RAGE IgG3 were injected into the rats three times a week. The diabetic state was evaluated by oral glucose tolerance tests (OGTTs), the homeostasis model assessment (HOMA), concentration of free fatty acids and repeated measurements of blood glucose. Markers of systemic inflammation, including interleukin (IL)-1ß, IL-6 and tumor necrosis factor α, were evaluated in plasma. Kidney complications were evaluated by quantitative real-time PCR, the creatinine clearance rate, the albumin excretion rate and kidney hypertrophy. Periodontitis was evaluated by morphometric registration of alveolar bone loss and radiographic recording of bone support. RESULTS: The diabetic state was improved by antibody treatment for 4 wk, resulting in a lower area under the glucose concentration curve during OGTTs, lower insulin levels and a lower HOMA. Furthermore, the antibody treatment resulted in milder kidney complications, as evaluated by measuring the albumin excretion rate and the kidney weight. There was no impact of periodontal inflammation on the level of complications. Periodontal bone support was influenced by diabetes, but the altered diabetic status as a result of treatment with anti-RAGE Ig had no effect on periodontitis. CONCLUSION: In this study, treatment with anti-RAGE IgG3 resulted in improved glucose tolerance and attenuated renal complications. However, no effect was observed on the diabetes-associated periodontitis in Zucker obese rats. Furthermore, periodontitis had no effect on diabetic markers or renal complications. Therefore, activation of RAGE is important in the development of T2D.

Low adiponectin levels at baseline and decreasing adiponectin levels over 10 years of follow-up predict risk of the metabolic syndrome.

AIM: Adiponectin is the most abundant adipokine and may play a key role in the interplay between obesity, inflammation, insulin resistance and the metabolic syndrome (MetS). Thus, this large population-based cohort investigated whether adiponectin at baseline and/or a decrease in adiponectin during follow-up is associated prospectively with the risk of incident MetS. METHODS: Using a prospective study design, the development of MetS was examined in 1134 healthy participants from the community. Plasma adiponectin was measured at study entry and again after a median follow-up of 9.4 years (IQR: 9.2-9.7). During follow-up, 187 participants developed MetS, and 439 presented with at least two components of MetS. RESULTS: During follow-up, adiponectin decreased in participants who developed MetS, whereas adiponectin was increased in those who did not develop MetS (P<0.001). Those with low adiponectin levels (quartile 1) at baseline had an increased risk of developing MetS (OR: 2.92, 2.08-6.97; P<0.001) compared with those with high levels (quartile 4). After adjusting for confounding variables, low adiponectin levels at baseline remained independently associated with MetS (OR: 2.24, 1.11-4.52; P=0.017). Similarly, participants with a decrease in adiponectin during follow-up also had an increased risk of MetS (OR: 2.96, 2.09-4.18; P<0.001). This association persisted after multivariable adjustments, including for baseline adiponectin (OR: 4.37, 2.77-6.97; P<0.001). Finally, adiponectin levels at follow-up were inversely associated with an increase in the number of components of MetS (P<0.001); geometric mean adiponectin levels were 9.5mg/L (95% CI: 9.0-10.0) for participants with no components vs 7.0mg/L (95% CI: 6.3-7.9) for those with four to five components. CONCLUSIONS/INTERPRETATION: Low plasma adiponectin levels at baseline and decreasing adiponectin levels during follow-up are both associated with an increased risk of MetS.

Plasma adiponectin in heart failure with and without cachexia: catabolic signal linking catabolism, symptomatic status, and prognosis.

BACKGROUND AND AIMS: Adiponectin (ADPN) as an adipose tissue hormone contributes to regulation of energy metabolism and body composition and is associated with cardiovascular risk profile parameters. Cardiac cachexia may develop as a result of severe catabolic derangement in chronic heart failure (CHF). We aimed to determinate an abnormal ADPN regulation as a link between catabolic signalling, symptomatic deterioration and poor prognosis. METHODS AND RESULTS: We measured plasma ADPN in 111 CHF patients (age 65 ± 11, 90% male, left ventricular ejection fraction (LVEF) 36 ± 11%, peak oxygen consumption (peakVO2) 18.1 ± 5.7 l/kg*min, body mass index (BMI) 27 ± 4 kg/m(2), all mean ± standard deviation) and 36 healthy controls of similar age and BMI. Body composition was assessed by dual energy X-ray absorptiometry, insulin sensitivity was evaluated by homoeostasis model assessment, exercise capacity by spiroergometry. Plasma ADPN did not differ between CHF vs. controls (13.5 ± 11.0 vs. 10.5 ± 5.3 mg/l, p > 0.4), but increased stepwise with NYHA functional class (I/II/III: 5.7 ± 1.4/10.7 ± 8.3/19.2 ± 14.0 mg/l, ANOVA p < 0.01). Furthermore, ADPN correlated with VO2 at anaerobic threshold (r = -0.34, p < 0.05). ADPN was highest in cachectic patients (cCHF, 16%) vs. non-cachectic (ncCHF) (18.7 ± 15.0 vs. 12.5 ± 9.9 mg/l; p < 0.05). ADPN indicated mortality risk independently of established prognosticators (HR: 1.04 95% CI: 1.02-1.07; p < 0.0001). ADPN above the mean (13.5 mg/l) was associated with a 3.4 times higher mortality risk in CHF vs. patients with ADPN levels below the mean. CONCLUSION: Circulating ADPN is abnormally regulated in CHF. ADPN may be involved in impaired metabolic signalling linking disease progression, tissue wasting, and poor outcome in CHF.

Diabetes-induced changes in mannan-binding lectin levels and complement activation in a mouse model of type 1 diabetes.

Circulating mannan-binding lectin (MBL) levels are elevated in type 1 diabetes. Further, high MBL levels are associated with the development of diabetic nephropathy. In animals, a direct effect of MBL on diabetic kidney changes is observed. We hypothesized that MBL levels and detrimental complement activation increase as a consequence of diabetes. We measured plasma MBL before and 7 weeks after inducing diabetes by streptozotocin. Mice have two MBLs, MBL-A and MBL-C. Diabetes induction led to an increase in MBL-C concentration, whereas no change during the study was found in the control group. The increase in MBL-C was associated with the increasing plasma glucose levels. In accordance with the observed changes in circulating MBL levels, liver expression of Mbl2mRNA (encoding MBL-C) was increased in diabetes. Mbl1expression (encoding MBL-A) did not differ between diabetic and control animals. The estimated half-life of recombinant human MBL was significantly prolonged in mice with diabetes compared with control mice. Complement activation in plasma and glomeruli did not differ between groups. We demonstrate for the first time that MBL levels increase after induction of diabetes and in parallel with increasing plasma glucose. Our findings support the previous clinical observations of increased MBL in type 1 diabetes. This change may be explained by alternations in both MBL production and turnover.

Local administration of insulin-like growth factor-I (IGF-I) stimulates tendon collagen synthesis in humans.

Collagen is the predominant structural protein in tendons and ligaments, and can be controlled by hormonal changes. In animals, injections of insulin-like growth factor I (IGF-I) has been shown to increase collagen synthesis in tendons and ligaments and to improve structural tissue healing, but the effect of local IGF-I administration on tendon collagen synthesis in human has not been studied. The purpose of this study was to study whether local injections of IGF-I would have a stimulating effect on tendon collagen synthesis. Twelve healthy nonsmoking men [age 62 ± 1 years (mean ± SEM), BMI 27 ± 1] participated. Two injections of either human recombinant IGF-I (0.1 mL Increlex©) or saline (control) into each patellar tendon were performed 24-h apart, respectively. Tendon collagen fractional synthesis rate (FSR) was measured by stable isotope technique in the hours after the second injection. Simultaneously, interstitial peritendinous (IGF-I) and [procollagen type I N-terminal propeptide (PINP)], as a marker for type I collagen synthesis, were determined by microdialysis technique. Tendon collagen FSR and PINP were significantly higher in the IGF-I leg compared with the control leg (P < 0.05). In conclusion, local IGF-I administration can directly enhance tendon collagen synthesis both within and around the human tendon tissue.

Changes in calcitropic hormones, bone markers and insulin-like growth factor I (IGF-I) during pregnancy and postpartum: a controlled cohort study.

UNLABELLED: Pregnancy and lactation cause major changes in calcium homeostasis and bone metabolism. This population-based cohort study presents the physiological changes in biochemical indices of calcium homeostasis and bone metabolism during pregnancy and lactation INTRODUCTION: We describe physiological changes in calcium homeostasis, calcitropic hormones and bone metabolism during pregnancy and lactation. METHODS: We studied 153 women planning pregnancy (n=92 conceived) and 52 non-pregnant, age-matched female controls. Samples were collected prior to pregnancy, once each trimester and 2, 16 and 36 weeks postpartum. The controls were followed in parallel. RESULTS: P-estradiol (E2), prolactin and 1,25-dihydroxyvitamin D (1,25(OH)2D) increased (p<0.001) during pregnancy, whereas plasma levels of parathyroid hormone (P-PTH) and calcitonin decreased (p<0.01). Insulin-like growth factor I (IGF-I) was suppressed (p<0.05) in early pregnancy but peaked in the third trimester. Postpartum, E2 was low (p<0.05); prolactin decreased according to lactation status (p<0.05). 1,25(OH)2D was normal and IGF-I was again reduced (p<0.05). P-PTH and calcitonin increased postpartum. From early pregnancy, markers of bone resorption and formation rose and fall, respectively (p<0.001). From the third trimester, bone formation markers increased in association with IGF-I changes (p<0.01). Postpartum increases in bone turnover markers were associated with lactation status (p<0.001). During lactation, plasma phosphate was increased, whereas calcium levels tended to be decreased which may stimulate PTH levels during and after prolonged lactation. CONCLUSION: The increased calcium requirements in early pregnancy are not completely offset by increased intestinal calcium absorption caused by high 1,25(OH)2D since changes in bone markers indicated a negative bone balance. The rise in bone formation in late pregnancy may be initiated by a spike in IGF-I levels. The high bone turnover in lactating women may be related to high prolactin and PTH levels, low E2 levels and perhaps increased parathyroid hormone-related protein levels.

Effects of transdermal estrogen on collagen turnover at rest and in response to exercise in postmenopausal women.

Menopause is associated with loss of collagen content in the skin and tendon as well as accumulation of noncontractile tissue in skeletal muscle. The relative role of hormones and physical activity on these changes is not known. Accordingly, in a randomized, controlled, crossover study we investigated effects of transdermal estrogen replacement therapy (ERT) on type I collagen synthesis in tendon and skeletal muscle in 11 postmenopausal women. Patches with estrogen (Evorel) were placed on the skin above the patellar tendons and compared with no patch (control period). On day 2 all subjects performed one-legged exercise, and thereafter the exercised leg (EX leg) was compared with the nonexercised leg (Rest leg). Microdialysis catheters were placed in front of the patellar tendons and in the vastus lateralis muscle of both legs at days 3 and 5. The collected dialysate was analyzed for procollagen type I NH(2)-terminal propeptide (PINP), insulin-like growth factor I (IGF-I), and interleukin-6 (IL-6). Neither loading (Rest leg vs. EX leg) nor treatment (control vs. ERT) influenced peritendinous PINP, whereas combined exercise and ERT enhanced muscle PINP after 72 h (interaction between loading and treatment P = 0.008). In neither skeletal muscle nor peritendinous fluid were IGF-I and IL-6 influenced by treatment or exercise. In conclusion, ERT was associated with enhanced synthesis of type I collagen in the skeletal muscle in response to acute exercise. In perspective, this indicates that the availability of estrogen in postmenopausal women is important for repair of muscle damage or remodeling of the connective tissue within the skeletal muscle after exercise.

Impaired myogenic tone in isolated cerebral and coronary resistance arteries from the goto-kakizaki rat model of type 2 diabetes.

AIM: Type 2 diabetes is associated with stroke and cardiac dysfunction. We therefore investigated isolated middle cerebral arteries and coronary septal arteries from the diabetic Goto-Kakizaki (GK) rat model of nonobese type 2 diabetes. METHODS: Myogenic tone and agonist-induced responses were investigated under isobaric conditions with simultaneous recording of [Ca2+]i. Rho-kinase and NO pathways were investigated using specific pharmacological tools. RESULTS: Arteries from GK rats developed less tone at pressures from 20 to 100 mm Hg than arteries from control Wistar (CW) rats while [Ca2+]i was similar. Blocking the Rho-kinase pathway decreased the pressure-induced development of tone and after blockade no difference in myogenic tone between arteries from GK and CW rats was seen. Cerebral arteries had similar tone to a maximal concentration of U46619 (GK: 35.5±2% vs. CW: 31.6±5%), while coronary arteries from GK rats developed less tone than arteries from CW rats (12±3 vs. 26.1±3%). Endothelium-dependent vasodilation to A23187 (cerebral) and to acetylcholine (coronary) was not different between arteries from GK and CW rats. CONCLUSION: Our data suggest that in resistance arteries from the brain and the heart of GK rats the myogenic tone is decreased due to impaired calcium sensitivity likely due to a defective Rho-kinase pathway.

Testosterone therapy decreases subcutaneous fat and adiponectin in aging men.

OBJECTIVE: Testosterone therapy increases lean body mass and decreases total fat mass in aging men with low normal testosterone levels. The major challenge is, however, to determine whether the metabolic consequences of testosterone therapy are overall positive. We have previously reported that 6-month testosterone therapy did not improve insulin sensitivity. We investigated the effect of testosterone therapy on regional body fat distribution and on the levels of the insulin-sensitizing adipokine, adiponectin, in aging men with low normal bioavailable testosterone levels. DESIGN: A randomized, double-blinded, placebo-controlled study on 6-month testosterone treatment (gel) in 38 men, aged 60-78 years, with bioavailable testosterone <7.3 nmol/l, and a waist circumference >94 cm. METHODS: Central fat mass (CFM) and lower extremity fat mass (LEFM) were measured by dual X-ray absorptiometry. Subcutaneous abdominal adipose tissue (SAT), visceral adipose tissue (VAT), and thigh subcutaneous fat area (TFA) were measured by magnetic resonance imaging. Adiponectin levels were measured using an in-house immunofluorometric assay. Coefficients (b) represent the placebo-controlled mean effect of intervention. RESULTS: LEFM was decreased (b = -0.47 kg, P = 0.07) while CFM did not change significantly (b = -0.66 kg, P = 0.10) during testosterone therapy. SAT (b = -3.0%, P = 0.018) and TFA (b = -3.0%, P < 0.001) decreased, while VAT (b = 1.0%, P = 0.54) remained unchanged. Adiponectin levels decreased during testosterone therapy (b = -1.3 mg/l, P = 0.001). CONCLUSION: Testosterone therapy decreased subcutaneous fat on the abdomen and lower extremities, but visceral fat was unchanged. Moreover, adiponectin levels were significantly decreased during testosterone therapy.

Plasma sCD36 is associated with markers of atherosclerosis, insulin resistance and fatty liver in a nondiabetic healthy population.

OBJECTIVES: Insulin resistance is associated with increased CD36 expression in a number of tissues. Moreover, excess macrophage CD36 may initiate atherosclerotic lesions. The aim of this study was to determine whether plasma soluble CD36 (sCD36) was associated with insulin resistance, fatty liver and carotid atherosclerosis in nondiabetic subjects. METHODS: In 1296 healthy subjects without diabetes or hypertension recruited from 19 centres in 14 European countries (RISC study), we determined the levels of sCD36, adiponectin, lipids and liver enzymes, insulin sensitivity (M/I) by euglycaemic-hyperinsulinaemic clamp, carotid atherosclerosis as intima-media thickness (IMT) and two estimates of fatty liver, the fatty liver index (FLI) and liver fat percentage (LF%). RESULTS: IMT, FLI, LF%, presence of the metabolic syndrome, impaired glucose regulation, insulin and triglycerides increased across sCD36 quartiles (Q2-Q4), whereas adiponectin and M/I decreased (P ≤ 0.01). sCD36 was lower in women than in men (P = 0.045). Log sCD36 showed a bimodal distribution, and amongst subjects with sCD36 within the log-normal distribution (log-normal population, n = 1029), sCD36 was increased in subjects with impaired glucose regulation (P = 0.045), metabolic syndrome (P = 0.006) or increased likelihood of fatty liver (P < 0.001). sCD36 correlated significantly with insulin, triglycerides, M/I and FLI (P < 0.05) after adjustment for study centre, gender, age, glucose tolerance status, smoking habits and alcohol consumption. In the log-normal population, these relationships were stronger than in the total study population and, additionally, sCD36 was significantly associated with LF% and IMT (P < 0.05). CONCLUSIONS: In this cross-sectional study of nondiabetic subjects, sCD36 was significantly associated with indices of insulin resistance, carotid atherosclerosis and fatty liver. Prospective studies are needed to further evaluate the role of sCD36 in the inter-relationship between atherosclerosis, fatty liver and insulin resistance.

Insulin-like growth factor I - a novel biomarker of abdominal aortic aneurysms.

OBJECTIVE: The study aimed to test the potential role of insulin-like growth factor I (IGF-I) and IGF-II as biomarkers for abdominal aortic aneurysm (AAA). METHODS AND RESULTS: IGF-I and II levels were analysed in 115 patients with screening diagnosed AAA kept under annual surveillance for 10 years. Serum IGF-I correlated positively with AAA size and growth rate (r = 0.23, P = 0.016 and r = 0.27, P = 0.004), persisting after adjustment for potential confounders. Serum IGF-I level predicted cases needing later surgery (AOC: 0.63; 95% confidence interval: 0.52-0.73). CONCLUSIONS: In this prospective, long-term study, baseline serum IGF-I correlated positively with AAA size and growth rate and predicted future need for preventive surgery.

Serum adiponectin concentration is a positive predictor of all-cause and cardiovascular mortality in type 1 diabetes.

BACKGROUND: Adiponectin is widely regarded as an anti-atherogenic, antioxidant and anti-inflammatory molecule. However, adiponectin concentration is paradoxically increased in individuals with type 1 diabetes, in whom it is positively associated with adverse clinical outcomes. OBJECTIVE: To explore the association between serum adiponectin concentration and mortality outcomes in adults with type 1 diabetes. DESIGN: Multicentre prospective cohort study. SETTING: Primary and tertiary care. SUBJECTS: Finnish adults with type 1 diabetes (n= 2034). Main outcome measures. All-cause and cardiovascular mortality. Independent predictors of mortality were determined using the Cox and the Fine and Gray competing risks proportional hazards models. RESULTS: During a median of 11 years of follow-up, there were 173 deaths (8.5%, 1.0 per hundred person-years). Adiponectin was linearly associated with all-cause mortality [Cox model: hazard ratio (HR) 1.02, 95% confidence interval (CI) 1.01-1.03, P<0.001] and cardiovascular mortality (Fine and Gray model: HR 1.02, 95% CI 1.00-1.04, P=0.035); patients with the highest adiponectin concentrations had the shortest survival. The mortality risk associated with adiponectin was independent of glycaemic and lipid control, pre-existing cardiovascular disease, markers of inflammation and the presence and severity of kidney disease. CONCLUSIONS: Although adiponectin is generally considered to be a protective molecule, increased concentrations of adiponectin in type 1 diabetes are independently associated with all-cause and cardiovascular mortality. Moreover, the fact that this association was observed for the first time in patients with normal urinary albumin levels, who have few comorbidities, suggests that adiponectin is specifically linked with vascular damage in type 1 diabetes.

Counter-regulatory hormone responses to spontaneous hypoglycaemia during treatment with insulin Aspart or human soluble insulin: a double-blinded randomized cross-over study.

AIMS: To compare insulin Aspart and human insulin with respect to glycaemic control, hypoglycaemic frequency and counter-regulatory responses to spontaneous hypoglycaemia. METHODS: Glycaemic control, hypoglycaemic frequency, p-insulin concentrations, insulin dosages and patients' satisfaction were examined in a randomized, double-blinded cross-over study for two periods of 8 weeks. Sixteen patients with type 1 diabetes were subjected to three daily injections of human soluble insulin or Aspart in addition to Neutral Protamine Hagedorn (NPH) insulin twice daily. Each intervention period was followed by hospitalization where episodes of spontaneous hypoglycaemia and counter-regulatory hormone responses were evaluated from frequently obtained blood samples. RESULTS: No difference between soluble insulin and insulin Aspart was found regarding HbA1c (7.0 ± 0.2 vs. 7.0 ± 0.2%, ns), hypoglycaemic frequency (1.1 ± 0.2 vs. 0.9 ± 0.1 events per patient per week, ns), nocturnal hypoglycaemia, severe hypoglycaemic events, dosages of bolus insulin (31.8 ± 0.4 vs. 30.0 ± 0.6 IU day(-1), ns), or NPH insulin (26.7 ± 1.8 vs. 26.0 ± 1.7 IU day(-1) , ns) or in patients satisfaction (ns). Modest differences existed in the counter-regulatory responses regarding growth hormone, glucagon and ghrelin whereas no differences were found in relation to free fatty acid, cortisol, insulin-like growth factor (IGF)-I, IGF-II and IGF-binding proteins 1 and 2. Treatment with insulin Aspart resulted in well-defined peaks in serum insulin concentrations as compared with more blunted insulin peaks using human soluble insulin. CONCLUSION: Although insulin Aspart treatment was associated with clear postprandial insulin peaks, no improvement in glycaemic control was obtained and no difference in the hypoglycaemic frequency was observed. However, insulin Aspart elicited a slightly different physiological response to spontaneous hypoglycaemia compared with human insulin.

Comparison of two sulfonylureas with high and low myocardial K(ATP) channel affinity on myocardial infarct size and metabolism in a rat model of type 2 diabetes.

AIMS/HYPOTHESIS: Sulfonylureas (SUs) may impair outcome in patients with acute coronary syndrome. Most experimental studies of the myocardial effects of SU treatment are performed in non-diabetic models. We compared the effect of two widely used SUs, glibenclamide (gb) and gliclazide (gc), with high and low myocardial K(ATP) channel affinity, respectively, at therapeutic concentrations on infarct size, left ventricular (LV) function and myocardial glycogen, lactate and alanine content before and after ischaemia/reperfusion (I/R). METHODS: Non-diabetic Wistar and diabetic Goto-Kakizaki rat hearts were investigated in a Langendorff preparation. Gb (0.1 µmol/l) and gc (1.0 µmol/l) were administrated throughout the study. Infarct size was evaluated after 120 min of reperfusion. Myocardial metabolite content was measured before and after ischaemia. RESULTS: Infarct size was smaller in diabetic hearts than in non-diabetic hearts (0.33 ± 0.03 vs 0.51 ± 0.05, p < 0.05). Gb increased infarct size (0.54 ± 0.04 vs 0.33 ± 0.03, p < 0.05) and reduced post-ischaemic LV developed pressure (60 ± 3 vs 76 ± 3 mmHg, p < 0.05) and coronary flow (4.9 ± 0.5 vs 7.1 ± 0.4 ml min(-1) g(-1), p < 0.05) in gb-treated diabetic rats compared with untreated diabetic rats. On comparing gb-treated diabetic rats with untreated diabetic rats, glycogen content was reduced before (9.1 ± 0.6 vs 13.6 ± 1.0 nmol/mg wet weight, p < 0.01) and after ischaemia (0.9 ± 0.2 vs 1.8 ± 0.2 nmol/mg wet weight, p < 0.05), and lactate (4.8 ± 0.4 vs 3.2 ± 0.3 nmol/mg wet weight, p < 0.01) and alanine (1.38 ± 0.12 vs 0.96 ± 0.09 nmol/mg wet weight, p < 0.05) contents were increased during reperfusion. Gc-treatment of diabetic and non-diabetic rats did not affect any of the measured variables. CONCLUSIONS/INTERPRETATIONS: Gb, but not gc, exacerbates I/R injury and deteriorates LV function in diabetic hearts. These effects of gb on diabetic hearts may be due to detrimental effects on myocardial carbohydrate metabolism.

The effects of intermittent or continuous energy restriction on weight loss and metabolic disease risk markers: a randomized trial in young overweight women.

BACKGROUND: The problems of adherence to energy restriction in humans are well known. OBJECTIVE: To compare the feasibility and effectiveness of intermittent continuous energy (IER) with continuous energy restriction (CER) for weight loss, insulin sensitivity and other metabolic disease risk markers. DESIGN: Randomized comparison of a 25% energy restriction as IER (∼ 2710 kJ/day for 2 days/week) or CER (∼ 6276 kJ/day for 7 days/week) in 107 overweight or obese (mean (± s.d.) body mass index 30.6 (± 5.1) kg m(-2)) premenopausal women observed over a period of 6 months. Weight, anthropometry, biomarkers for breast cancer, diabetes, cardiovascular disease and dementia risk; insulin resistance (HOMA), oxidative stress markers, leptin, adiponectin, insulin-like growth factor (IGF)-1 and IGF binding proteins 1 and 2, androgens, prolactin, inflammatory markers (high sensitivity C-reactive protein and sialic acid), lipids, blood pressure and brain-derived neurotrophic factor were assessed at baseline and after 1, 3 and 6 months. RESULTS: Last observation carried forward analysis showed that IER and CER are equally effective for weight loss: mean (95% confidence interval ) weight change for IER was -6.4 (-7.9 to -4.8) kg vs -5.6 (-6.9 to -4.4) kg for CER (P-value for difference between groups = 0.4). Both groups experienced comparable reductions in leptin, free androgen index, high-sensitivity C-reactive protein, total and LDL cholesterol, triglycerides, blood pressure and increases in sex hormone binding globulin, IGF binding proteins 1 and 2. Reductions in fasting insulin and insulin resistance were modest in both groups, but greater with IER than with CER; difference between groups for fasting insulin was -1.2 (-1.4 to -1.0) µU ml(-1) and for insulin resistance was -1.2 (-1.5 to -1.0) µU mmol(-1) l(-1) (both P = 0.04). CONCLUSION: IER is as effective as CER with regard to weight loss, insulin sensitivity and other health biomarkers, and may be offered as an alternative equivalent to CER for weight loss and reducing disease risk.

Identification of differentially expressed genes in the kidneys of growth hormone transgenic mice.

OBJECTIVE: Bovine growth hormone (bGH) transgenic mice develop severe kidney damage. This damage may be due, at least in part, to changes in gene expression. Identification of genes with altered expression in the bGH kidney may identify mechanisms leading to damage in this system that may also be relevant to other models of kidney damage. DESIGN: cDNA subtraction libraries, northern blot analyses, microarray analyses and real-time reverse transcription polymerase chain reaction (RT/PCR) assays were used to identify and verify specific genes exhibiting differential RNA expression between kidneys of bGH mice and their non-transgenic (NT) littermates. RESULTS: Immunoglobulins were the vast majority of genes identified by the cDNA subtractions and the microarray analyses as being up-regulated in bGH. Several glycoprotein genes and inflammation-related genes also showed increased RNA expression in the bGH kidney. In contrast, only a few genes were identified as being significantly down-regulated in the bGH kidney. The most notable decrease in RNA expression was for the gene encoding kidney androgen-regulated protein. CONCLUSIONS: A number of genes were identified as being differentially expressed in the bGH kidney. Inclusion of two groups, immunoglobulins and inflammation-related genes, suggests a role of the immune system in bGH kidney damage.

Adiponectin and peak bone mass in men: a cross-sectional, population-based study.

Adiponectin, a protein classically known to be secreted by adipocytes, is also secreted by bone-forming cells. Results of previous studies have been contradictory as to whether serum adiponectin and bone mineral density (BMD) are associated. The aim of this study was to investigate a possible association between serum adiponectin and BMD in young, healthy men at a time of peak bone mass. BMD in the femoral neck, total hip, and lumbar spine were measured in this population-based cross-sectional study of 700 men aged 20-29 years participating in the Odense Androgen Study. Magnetic resonance imaging of femoral cortical thickness and bone marrow size was performed in a subsample of 363 participants. The associations between serum adiponectin and various bone measures were investigated by means of regression analyses with adjustment for potential confounding variables. An inverse association was found between serum adiponectin and total hip BMD and a direct between adiponectin and femoral bone marrow size (r = -0.092; P = 0.036 and r = 0.164; P = 0.003, respectively). Femoral muscle size may, at least in part, explain the association between adiponectin and total hip BMD. Serum adiponectin was inversely associated with total hip BMD in men at the time of peak bone mass, but this association may be explained by factors related to muscle size and function. The observed association between adiponectin and femoral bone marrow size was retained even after adjustment for potential covariates.

Association between mannose-binding lectin, high-sensitivity C-reactive protein and the progression of diabetic nephropathy in type 1 diabetes.

AIMS/HYPOTHESIS: Diabetic nephropathy has been associated with low-grade inflammation and activation of the complement system in cross-sectional studies. Data from prospective studies are sparse. We investigated the associations of the complement activator mannose-binding lectin (MBL) and the inflammatory marker high-sensitivity C-reactive protein (hsCRP) with the development of nephropathy in a large prospective study of patients with type 1 diabetes from the Finnish Diabetic Nephropathy (FinnDiane) Study. METHODS: Baseline MBL and hsCRP were measured in 1,564 type 1 diabetes patients from the FinnDiane study, of whom 1,010 had a normal albumin excretion rate, 236 had microalbuminuria and 318 had macroalbuminuria. The main outcome was progression in renal disease during follow-up. RESULTS: Both baseline MBL (p = 0.038) and hsCRP (p < 0.001) increased with increasing level of albuminuria. During 5.8 +/- 2.2 years of follow-up, progression to a higher albuminuria level or end-stage renal disease (ESRD) occurred in 201 patients. MBL levels were higher in progressors compared with non-progressors at all steps of progression, and in a covariate adjusted multivariate Cox-regression analysis MBL levels above the median were significantly associated with progression from macroalbuminuria to ESRD (hazard ratio 1.88, 95% CI 1.06-3.32, p = 0.030). In a univariate analysis, hsCRP levels above the median were significantly associated with progression from normal albumin excretion rate to microalbuminuria, but the association was only borderline significant after adjustment for covariates (hazard ratio 1.56, 95% CI 0.97-2.51, p = 0.068). CONCLUSIONS/INTERPRETATION: This study demonstrates that concentrations of both MBL and hsCRP are associated with the progression of renal disease in type 1 diabetes.

Total adiponectin does not predict cardiovascular events in middle-aged men in a prospective, long-term follow-up study.

AIM: Plasma total adiponectin is a marker of insulin resistance, but its role in predicting cardiovascular events is unclear. We aimed to investigate the role of adiponectin as a predictor of cardiovascular risk in middle-aged men, and to describe the association between adiponectin and glucose metabolism. METHODS: In this population-based prospective study of middle-aged men (n=3885), total adiponectin was analyzed. All individuals had undergone an oral glucose tolerance test (OGTTs), and the mean follow-up duration was 27 years. Regression analyses were carried out for indices of glucose metabolism in relation to quintiles (Q1-Q5) of total adiponectin levels. After stratification for smoking or not, the association between total adiponectin and the first incidence of fatal or non-fatal cardiovascular disease (CVD) was analyzed, using Cox's proportional-hazards regression model. RESULTS: In a separate multiple-regression analysis and after adjusting for possible confounders, the relationship between adiponectin levels and markers of glucose metabolism were found to be significant (P<0.05). However, adiponectin did not independently predict the risk of stroke, coronary events, or a combination of these two outcomes. CONCLUSION: Levels of total plasma adiponectin are not useful for predicting long-term cardiovascular events in middle-aged men, but are strongly associated with glucose metabolism and markers of insulin resistance.