Successful Management of Type 2 Diabetes with Lifestyle Intervention: A Case Report.

BACKGROUND: The prevalence of diabetes is growing worldwide. The primary symptom of diabetes mellitus is elevated blood sugar. This is usually treated with lifestyle intervention and drugs according to an algorithm based on glycated hemoglobin (HbA1c) levels. We present the case of a patient who successfully managed his type 2 diabetes solely through lifestyle modification. CASE REPORT: A 45-year-old businessman with a body mass index of 27 kg/m2 was examined within a secondary prevention program in Austria. His HbA1c was 9.7%-type 2 diabetes mellitus was diagnosed. General recommendations for lifestyle were given and metformin was prescribed. Upon his diagnosis the patient searched for all the information he could get about diabetes and implemented this new knowledge in his everyday life. He had a strong desire to defeat his disease and he wanted to stop using medications. He identified some nutritional ingredients and spices that affected his blood sugar in a positive way. He stopped taking metformin after 4 weeks and handled his diabetes with his personal lifestyle program. Three months after the diagnosis his HbA1c was 6.4%; after 6 months he had an HbA1c of 6.0% without the use of medication. DISCUSSION: Usually, multiple drug therapy is necessary to handle high blood glucose levels. Our business manager ate as much as before his diagnosis but he modified the contents of his diet so that the lifestyle intervention was not hard for him. General recommendations for lifestyle modification usually include: more exercise, reduced sugar and monosaccharides, and less alcohol and nicotine. With the knowledge of the effects of specific dietary ingredients, it might be possible to modify a regular diet in such a way as to benefit people with type 2 diabetes, to substantially improve quality of life.

A transient improvement in renal function occurs after ischemic stroke.

BACKGROUND: Neurohumoral effects have been suggested to affect kidney function. Stroke is a condition where regulation of the renin-angiotensin system and sympathetic nerve activity are altered. METHODS: Renal function as estimated by serum creatinine was analyzed over 1 week in 220 patients after acute ischemic stroke. RESULTS: In patients with chronic kidney disease defined as those with serum creatinine >1.2 mg/dL at admission (n = 62), renal function transiently improved, measured by a mean decrease of creatinine of 0.34 mg/dL during the first days after stroke. A significant and transient decrease of creatinine was also observed in patients with diabetes (n = 69) or patients with heart failure (n = 89). In both subgroups creatinine decreased by a mean of 0.49 and 0.24 mg/dL, respectively (p < 0.05 for both). In patients with normal renal function at admission, no change in serum creatinine occurred during the first week after stroke. There was no association between stroke severity and creatinine change. CONCLUSION: An acute ischemic cerebrovascular event intermittently improves impaired kidney function. The underlying mechanism may involve central regulation of renal function.

Forearm vasodilator reactivity in homozygous carriers of the 9p21.3 rs1333049 G>C polymorphism.

AIM: Recently, a novel susceptibility locus for coronary artery disease (CAD) has been identified on chromosome 9p21.3, linked to the single-nucleotide polymorphism (SNP) rs1333049 G>C. However, the physiological mechanism through which this locus confers an increased CAD-risk is still unknown. The aim of the present case-control study was to test whether this chromosome 9p21.3 locus, represented by the rs1333049 variant, is associated with altered vasodilator resistance vessel function in healthy young volunteers. DESIGN AND RESULTS: A total of 97 healthy male volunteers were screened for homozygous carriers of either the G- or the C-allele, the minor allele in European populations. Forearm blood flow (FBF) reactivity to acetylcholine (ACh) and glycerol trinitrate (GTN) was then studied in 10 C/C-genotype carriers compared with 10 control subjects harbouring the G/G-genotype. FBF responses to ACh and GTN were reduced in subjects homozygous for the C-allele of the rs1333049 SNP (P < 0.05). FBF reactivity to the highest dose of ACh and GTN was 95% and 74% lower when compared with control subjects with the G/G-genotype. CONCLUSION: Our study revealed a functional impairment in forearm artery vasodilator resistance in carriers of the rs1333049 C/C-genotype, thus providing evidence for a first physiological functional link underlying the genetic association of the 9p21.3 locus with an increased cardiovascular risk.

Asymmetrical dimethylarginine, inflammatory and metabolic parameters in women with polycystic ovary syndrome before and after metformin treatment.

CONTEXT: Insulin resistance plays a significant role in the pathogenesis of the polycystic ovary syndrome (PCOS) and represents a link to the unfavorable cardiovascular risk profile frequently found in affected patients. The endogenous nitric oxide synthase inhibitor asymmetrical dimethyl-L-arginine (ADMA) is associated with atherosclerosis and represents an independent marker for cardiovascular morbidity and mortality. OBJECTIVE: We investigated ADMA levels among other cardiovascular, metabolic, and hormonal parameters in women with PCOS and the effects of metformin treatment on these parameters. DESIGN: A cross-sectional study and clinical trial were performed. PATIENTS AND PARTICIPANTS: Women with PCOS (n = 83) compared with a control group of healthy women (n = 39) were studied. INTERVENTIONS: In a subgroup of patients with PCOS (n = 21), the effect of metformin was assessed after 6 months of treatment. MAIN OUTCOME MEASURES: ADMA, intima media thickness (IMT), metabolic and hormonal parameters, and markers of inflammation were investigated. RESULTS: ADMA levels were significantly higher in the PCOS group compared with controls (0.57 +/- 0.15 vs. 0.50 +/- 0.11; P = 0.024). Androgens, C-reactive protein, fasting C-peptide, area under the curve (AUC) insulin, AUC glucose, homeostatic assessment of insulin resistance, fasting insulin, glycosylated hemoglobin, cholesterol, low-density lipoprotein cholesterol, triglycerides, and IMT were significantly higher in women with PCOS compared with controls. In PCOS patients ADMA was found to be positively correlated with body mass index (BMI), waist to hip ratio, parameters of insulin sensitivity, hyperandrogenemia (free testosterone, free androgen index), and IMT. Treatment with metformin ameliorated hyperandrogenemia and decreased ADMA levels (0.53 +/- 0.06 vs. 0.46 +/- 0.09, P = 0.013). Decrease in ADMA levels subsequent to metformin treatment did not correlate with change in BMI or metabolic parameters. CONCLUSIONS: ADMA amd parameters of insulin sensitivity are elevated in women with PCOS and the degree of insulin resistance confers the greatest influence on ADMA level. Metformin treatment led to improvement of hormonal and metabolic parameters and decreased ADMA levels possibly independent of BMI and metabolic changes.

Asymmetric dimethylarginine enhances cardiovascular risk prediction in patients with chronic heart failure.

OBJECTIVE: The purpose of this study was to investigate whether elevated asymmetrical dimethylorginine (ADMA) concentrations are associated with increased cardiovascular risk in chronic heart failure (HF) patients. METHODS AND RESULTS: 253 patients with symptomatic chronic HF and impaired left ventricular function (median age 70 years, 202 males) were followed for a median of 14.2 months (interquartile range 6.8 to 21.2). ADMA and N-terminal pro-brain natriuretic peptide (NT-proBNP) were assessed by high performance liquid chromatography and by an enzyme-linked immunosorbent assay, respectively. Subjects with ADMA concentrations in the highest tertile had a significantly higher adjusted hazard ratio (HR; 2.00; 95% confidence interval [CI] 1.01 to 3.97) for occurrence of an end point (cardiac decompensation, major adverse cardiovascular events or all-cause mortality) compared with patients in the lowest tertile (P=0.046) during the first 6 months of follow-up. NT-proBNP also identified subjects at risk before adjustment for confounders at 6 and 12 months of follow-up. HR for patients with ADMA and NT-proBNP in the highest tertile was significantly increased (3.68, CI 1.67 to 8.14; at 6 months follow-up) compared with patients without ADMA and NT-proBNP in the highest tertile (P<0.001). CONCLUSIONS: Elevated ADMA plasma concentrations are associated with adverse cardiovascular outcome in patients with chronic HF. Quantification of ADMA with NT-proBNP improves risk stratification in this cohort.

Asymmetric dimethylarginine is increased in chronic thromboembolic pulmonary hypertension.

RATIONALE: Asymmetric dimethylarginine (ADMA), a potent endogenous nitric oxide synthase (NOS) inhibitor, is increased in idiopathic pulmonary arterial hypertension and associated with unfavorable outcome. OBJECTIVES: Chronic thromboembolic pulmonary hypertension (CTEPH), although principally amenable to surgical removal of major pulmonary arterial obstructions by pulmonary endarterectomy, may show a small-vessel pulmonary arteriopathy similar to idiopathic pulmonary arterial hypertension. We hypothesized that ADMA plasma levels are increased in patients with CTEPH. METHODS: We measured ADMA by high-performance liquid chromatography at the time of diagnosis in 135 patients with CTEPH. Inoperability in 66 patients was based on an imbalance between severity of pulmonary hypertension and morphologic lesions. MEASUREMENTS AND MAIN RESULTS: ADMA plasma levels were significantly elevated in patients, compared with 40 matched control subjects (0.62 [0.51-0.73] vs. 0.51 [0.45-0.6] micromol/L, P = 0.0002). At baseline, ADMA plasma concentrations correlated with mixed venous saturation (r = -0.25, P = 0.005), right atrial pressure (r = 0.35, P < 0.0001), and cardiac index (r = -0.21, P = 0.01). Patients who underwent surgery demonstrated lower ADMA levels at baseline than inoperable patients (0.60 [0.5-0.68] vs. 0.63 [0.53-0.85] micromol/L, P = 0.02), with a further decrease 12 +/- 1 months after pulmonary endarterectomy (P = 0.02). Endothelial NOS expression in endothelial cells was low in patients with elevated ADMA plasma levels. Survival of patients with ADMA plasma levels >/= 0.64 micromol/L was worse than in patients with ADMA plasma levels < 0.64 micromol/L. CONCLUSIONS: ADMA plasma levels correlate with the severity of pulmonary vascular disease and predict outcome in patients with CTEPH. Measurement of ADMA plasma levels may be useful for estimating the degree of small-vessel arteriopathy in CTEPH.

Rosiglitazone prevents free fatty acid-induced vascular endothelial dysfunction.

CONTEXT: Free fatty acids (FFAs) cause insulin resistance and vascular endothelial dysfunction. The peroxisome proliferator-activated receptor gamma agonist rosiglitazone acts as insulin sensitizer and could exert vasoprotective properties by preservation of endothelium-dependent vasodilation. OBJECTIVE: We tested the effect of rosiglitazone on FFA-induced endothelial dysfunction of the forearm resistance vessels, insulin sensitivity, asymmetric dimethylarginine (ADMA), and high-sensitivity C-reactive protein concentrations in humans. DESIGN AND SETTING: We conducted a double-blind, randomized, placebo-controlled parallel-group study at a university hospital. PATIENTS AND INTERVENTIONS: Rosiglitazone 8 mg daily or placebo was administered to 16 healthy male subjects for 21 d. On the last day, triglycerides and heparin were infused iv to increase FFA plasma concentrations. MAIN OUTCOME MEASURES: Forearm blood flow responses to the endothelium-dependent vasodilator acetylcholine and the endothelium-independent vasodilator nitroglycerine were assessed using strain-gauge plethysmography at baseline, and on d 21 before and after 5 h of triglyceride/heparin infusion. RESULTS: Forearm blood flow reactivity was not affected by rosiglitazone or placebo. Infusion of triglyceride/heparin substantially increased FFA concentrations (P < 0.001) and reduced endothelium-dependent vasodilation by 38 +/- 17% (P = 0.024). In the face of lower FFA elevation (P = 0.047 vs. controls), endothelium-dependent vasodilation was preserved in subjects receiving rosiglitazone (P = 0.016 vs. placebo). Endothelium-independent vasodilation and C-reactive protein were unchanged, whereas insulin sensitivity and plasma ADMA similarly decreased in both study groups after FFA elevation (both P < 0.05 vs. baseline). CONCLUSIONS: Rosiglitazone mitigates the increase in FFA after infusion of triglyceride/heparin and prevents FFA-induced endothelial dysfunction. These effects are independent and possibly occur before any changes in insulin sensitivity and ADMA plasma concentrations in healthy subjects.

Asymmetric dimethylarginine predicts major adverse cardiovascular events in patients with advanced peripheral artery disease.

OBJECTIVE: Circulating concentrations of asymmetric dimethylarginine (ADMA), an endogenous inhibitor of nitric oxide synthesis, are elevated in conditions associated with increased cardiovascular risk. We investigated whether elevated ADMA concentrations predict major adverse cardiovascular events (MACE) in patients with advanced peripheral artery disease (PAD). METHODS AND RESULTS: We prospectively enrolled 496 of 533 consecutive patients with PAD (median age 70 years, 279 males). ADMA and L-arginine were assessed at baseline by high performance liquid chromatography. The occurrence of MACE (myocardial infarction, percutaneous coronary intervention, coronary artery bypass graft, stroke, carotid revascularization, death) was evaluated during a follow-up of median 19 months (interquartile range 11 to 25). One hundred eighty-two MACE were observed in 141 patients (28%). MACE occurred in 39% of the patients in the highest quartile and 26% of those in the lowest quartile of ADMA (P=0.016, log-rank test for all quartiles). Adjusted hazard ratios for occurrence of MACE for increasing quartiles of ADMA compared with the lowest quartile were 0.87 (95% confidence interval [CI], 0.51 to 1.48), 1.12 (95% CI, 0.62 to 1.90), and 1.70 (95% CI, 1.02 to 2.88), respectively. We observed no association between cardiovascular outcome and L-arginine. CONCLUSIONS: High ADMA plasma concentrations independently predict MACE in patients with advanced PAD. This indicates that ADMA may be a new cardiovascular risk marker in these patients.

Impaired vascular nitric oxide bioactivity in women with previous gestational diabetes.

BACKGROUND: Dysfunction of the vascular endothelium, preceding vascular morbidity and type 2 diabetes, is present in women with previous gestational diabetes (GDM). However, it is unknown whether excess weight, insulin resistance, and asymmetric dimethylarginine (ADMA)--an endogenous nitric oxide (NO) synthase inhibitor--also contribute to the vascular changes observed in these patients. The aim of this study was therefore to identify factors other than GDM that impair vascular function. METHODS: Seven overweight and five non-overweight women with previous GDM were included in this study. Vascular function was assessed from forearm blood-flow responses to the endothelium-dependent vasodilator acetylcholine (ACh), the endothelium-independent vasodilator glyceryltrinitrate, the vasoconstrictor norepinephrine and the NO synthase inhibitor N(G)-monomethyl-L-arginine (L-NMMA). ADMA was measured in venous blood, and insulin resistance was estimated from a modified intravenous glucose tolerance test. Twenty healthy male volunteers served as a historical control group. RESULTS: Vasodilation of forearm resistance vessels in response to ACh was impaired in overweight women when compared with non-overweight women (P < 0.05); similarly, vasoconstrictor reactivity tended to be smaller in the overweight group. In addition, there was a significant relationship between vascular responsiveness to ACh and L-NMMA, body-mass index, serum ADMA concentrations and stimulated glucose levels (all P < 0.05). ACh responses and ADMA levels in non-overweight women were similar to those of healthy controls. CONCLUSION: Factors such as obesity, increased ADMA levels and insulin resistance appear to be strong contributors to endothelial dysfunction observed in women with GDM.

Addressing Unmet Medical Needs in Type 1 Diabetes: A Review of Drugs Under Development.

INTRODUCTION: The incidence of type 1 diabetes (T1D) is increasing worldwide and there is a very large need for effective therapies. Essentially no therapies other than insulin are currently approved for the treatment of T1D. Drugs already in use for type 2 diabetes and many new drugs are under clinical development for T1D, including compounds with both established and new mechanisms of action. Content of the Review: Most of the new compounds in clinical development are currently in Phase 1 and 2. Drug classes discussed in this review include new insulins, SGLT inhibitors, GLP-1 agonists, immunomodulatory drugs including autoantigens and anti-cytokines, agents that regenerate ß-cells and others. Regulatory Considerations: In addition, considerations are provided with regard to the regulatory environment for the clinical development of drugs for T1D, with a focus on the United States Food and Drug Administration and the European Medicines Agency. Future opportunities, such as combination treatments of immunomodulatory and beta-cell regenerating therapies, are also discussed.

Asymmetric dimethylarginine is associated with macrovascular disease and total homocysteine in patients with type 2 diabetes.

BACKGROUND: The endogenous nitric oxide synthase inhibitor asymmetric dimethylarginine (ADMA) and total homocysteine (tHcy) are elevated in patients at increased cardiovascular risk. Patients with type 2 diabetes (T2DM) have higher incidence of macrovascular disease than the general population. Recent reports suggest a relationship between tHcy and ADMA. To evaluate the connection between ADMA and tHcy and macrovascular disease, we determined both risk factors in T2DM patients with and without macrovascular disease. SUBJECTS AND METHODS: Plasma concentrations of ADMA and tHcy were cross-sectionally determined in 136 T2DM patients. Fifty-five patients had macrovascular disease defined by history of stroke, myocardial infarction, coronary heart disease or peripheral arterial occlusive disease. Logistic regression analysis was performed to examine the relationship between macrovascular disease and these risk factors. Potential confounders were identified by significant Spearman rank correlation coefficients. RESULTS: In unadjusted models ADMA (per 0.1 micromol/l) and tHcy (per 5 micromol/l) were both significantly related to macrovascular disease (OR=1.63, 95% CI: 1.21-2.19 and OR=1.49, 95% CI: 1.04-2.14). In multivariate models, ADMA was significantly associated with macrovascular disease independent of l-arginine, albumin excretion rate, tHcy and glomerular filtration rate (GFR; OR=1.53, 95% CI: 1.04-2.26). The connection between tHcy and macrovascular disease was not independent of diastolic blood pressure, age, ADMA or GFR. Linear regression analyses revealed that ADMA, GFR and low-density lipoprotein cholesterol were independent predictors for tHcy. CONCLUSION: ADMA is associated with macrovascular disease independent of tHcy and traditional cardiovascular risk factors in patients with T2DM.

Umbilical vein plasma concentrations of asymmetrical dimethylarginine are increased in male but not female neonates delivered preterm: a pilot study.

BACKGROUND: Infants born term have substantially elevated plasma concentrations of the endogenous nitric oxide synthase antagonist asymmetrical dimethylarginine (ADMA) that normalize with growth. The plasma levels of ADMA in preterm newborns are unknown. SUBJECTS AND METHODS: Plasma concentrations of ADMA, symmetrical dimethylarginine (SDMA) and L-arginine were analyzed from venous umbilical cord blood samples of 19 preterm and 21 term infants by high performance liquid chromatography. RESULTS: Male preterm newborns (n=11) had higher ADMA (median [95% confidence interval (CI)]: 1.90 [1.73-2.10] micromol/l) than females born preterm (n=8; 1.57 [1.24-1.69] micromol/l; p<0.005). In term born males (n=10) and females (n=11) ADMA was significantly lower than in preterm male infants (all p<0.005), and without sex differences. SDMA and L-arginine concentrations were comparable between all groups. ADMA correlated inversely with body weight in male preterm newborns (r=-0.67; p<0.03). CONCLUSION: Male neonates delivered preterm have significantly higher umbilical cord venous plasma concentrations of ADMA compared to female neonates and infants born term. The sex difference and the time course of elevated ADMA may play a role in development and warrant further investigation.

High doses of vitamin C reverse Escherichia coli endotoxin-induced hyporeactivity to acetylcholine in the human forearm.

BACKGROUND: Acute inflammation causes endothelial vasodilator dysfunction that may be mediated by oxidative stress. METHODS AND RESULTS: In this randomized, double-blind, crossover study, forearm blood flow responses to acetylcholine (ACh) (endothelium-dependent dilator) and glyceryl-trinitrate (GTN) (endothelium-independent dilator) were assessed before and after induction of acute systemic inflammation by low doses of Escherichia coli endotoxin (LPS) (20 IU/kg IV) in 8 healthy volunteers. The acute effect of intra-arterial vitamin C (24 mg/min) or placebo was studied 4 hours after LPS, respectively. Vitamin C alone was administered in control experiments. LPS administration caused systemic vasodilation, increased white blood count, elevated body temperature, and reduced vitamin C plasma concentrations. LPS decreased the responses of forearm blood flow to ACh by 30% (P<0.05) but not to GTN. Vitamin C completely restored the response to ACh, which was comparable with that observed under baseline conditions. Vitamin C had no effect on basal blood flow or ACh- or GTN-induced vasodilation in control subjects. CONCLUSIONS: Our data demonstrate that impaired endothelial vasodilation caused by E coli endotoxemia can be counteracted by high doses of antioxidants in vivo. Oxidative stress may play an important role in the pathogenesis of endothelial dysfunction during inflammation.

Simvastatin prevents vascular hyporeactivity during inflammation.

BACKGROUND: There is growing evidence that statins exert anti-inflammatory and antioxidative vascular actions that are independent of lipid lowering. We tested whether hyporeactivity to the endothelium-dependent vasodilator acetylcholine (ACh) and the vasoconstrictor norepinephrine (NE) during acute experimental inflammation could be prevented by simvastatin. METHODS AND RESULTS: In a randomized, placebo-controlled, parallel group study, forearm blood flow (FBF) responses to NE, ACh, and the endothelium-independent vasodilator nitroglycerin (NTG) were assessed at baseline, after 4 days of simvastatin 80 mg PO or placebo treatment, and during Escherichia coli endotoxin (lipopolysaccharide [LPS])-induced inflammation in 20 healthy volunteers. Additionally, markers of inflammation and neutrophil oxidative burst were assessed. Simvastatin and placebo had no effect on FBF or oxidative/inflammatory markers. LPS administration decreased the responses of FBF to NE by 43% (P<0.05) and decreased responses to ACh by 48% (P<0.05) but did not decrease FBF responses to NTG. Simvastatin completely preserved responses to NE and to ACh. The LPS-induced increases in neutrophil oxidative burst and plasma tumor necrosis factor-alpha concentrations were mitigated by simvastatin (P<0.05 versus placebo). CONCLUSIONS: This study demonstrates potent vasoprotective properties of high-dose simvastatin during endotoxemia that may be useful for patients with acute systemic inflammation and associated vascular hyporeactivity.

Homocyst(e)ine-lowering therapy does not affect plasma asymmetrical dimethylarginine concentrations in patients with peripheral artery disease.

BACKGROUND: Elevated plasma asymmetrical dimethylarginine (ADMA) is suggested to contribute to hyperhomocyst(e)ine-related vascular dysfunction in patients with peripheral artery disease (PAD). The present trial investigated whether homocyst(e)ine (Hcy)-lowering therapy with vitamin-B (vit-B) and folic acid affects plasma concentrations of ADMA in patients with PAD and hyperhomocyst(e)inemia. SUBJECTS AND METHODS: Forty-nine subjects (15 women, 34 men) with PAD and fasting plasma total Hcy concentrations greater than 15 micromol/liter were randomized to receive either oral vit-B and folic acid therapy (n = 27) or placebo (n = 22) for 6 wk. Fasting venous blood samples were monitored for plasma total Hcy, vit-B12 and folate, ADMA, symmetric dimethylarginine, L-arginine, and high-sensitivity C-reactive protein. RESULTS: After 6 wk, plasma Hcy concentrations were decreased, and concentrations of vit-B12 and folate were elevated in patients with vitamin supplementation (all P < 0.05 vs. baseline) and unchanged in the placebo group. Dimethylarginine plasma concentrations were not affected by treatment. High-sensitivity C-reactive protein correlated with ADMA plasma concentrations (r = 0.29; P < 0.01). CONCLUSION: The lack of vit-B and folic acid therapy on plasma concentrations of ADMA renders a role of extracellular methylarginines unlikely to be involved in the pathophysiology of hyperhomocyst(e)inemia and its complications.

Inflammation-induced vasoconstrictor hyporeactivity is caused by oxidative stress.

OBJECTIVES: We sought to determine the role of oxidative stress in the development of vascular dysfunction in inflammation. BACKGROUND: Hyporeactivity to catecholamines and other vasoconstrictors is present in acute inflammation. Because oxidative stress plays a significant role in inflammation, impaired responsiveness may be overcome by anti-oxidants. METHODS: In randomized, double-blind, cross-over studies, forearm blood flow (FBF) responses to norepinephrine (NE), angiotensin II (ANG II), and vasopressin (VP) were assessed before and 4 h after induction of systemic inflammation by low doses of Escherichia coli endotoxin (lipopolysaccharide [LPS], 20 IU/kg intravenously) or after placebo in healthy volunteers. Furthermore, the effect of intra-arterial vitamin C (24 mg/min) or placebo on NE-induced or ANG II-induced vasoconstriction was studied after LPS. RESULTS: Administration of LPS caused systemic and forearm vasodilation, increased white blood cell count, elevated body temperature, and reduced vitamin C plasma concentrations. Lipopolysaccharide decreased the responses of FBF to NE by 59%, to ANG II by 25%, and to VP by 51% (n = 9, p < 0.05, all effects). Co-administration of vitamin C completely restored the response to NE and to ANG II, which was comparable to that observed under baseline conditions (n = 8). CONCLUSIONS: E. coli-endotoxemia reduces FBF responsiveness to vasoconstrictors. The hyporeactivity can be corrected by high doses of vitamin C, suggesting that oxidative stress may represent an important target for inflammation-induced impaired vascular function.

Regular physical exercise normalizes elevated asymmetrical dimethylarginine concentrations in patients with type 1 diabetes mellitus.

INTRODUCTION: Levels of the endogenous nitric oxide synthase inhibitor asymmetrical dimethylarginine (ADMA) are elevated in patients with type 1 diabetes mellitus (DM1) and may contribute to vascular complications. In this study we tested the hypothesis that elevated ADMA in patients with DM1 can be reduced by regular physical exercise. METHODS: Plasma samples for analysis of L-arginine, ADMA, symmetrical dimethylarginine (SDMA) and metabolic parameters were obtained from 11 patients with DM1 who participated in a supervised aerobic exercise program for four months. Samples were collected before the training began, at two and four months after initiation, and eight months after cessation of regular training. Fifteen age- and sex-matched healthy persons who did not exercise regularly were examined once as controls and did not participate in the training program. RESULTS: The patients with DM1 had higher ADMA levels than the controls before the training program began (0.54 +/- 0.02 vs. 0.44 +/- 0.03 micromol/l; P < 0.05). After two and four months of exercise, ADMA concentrations in the patients decreased to those seen in healthy persons (0.42 +/- 0.02 and 0.43 +/- 0.03 micromol/l; P < 0.001 and P < 0.05 compared with ADMA levels before training began). Eight months after cessation of the exercise program, ADMA levels in the patients reverted to those observed before the start of training. The L-arginine-to-ADMA ratio increased slightly after two months; L-arginine, symmetrical dimethylarginine, blood lipids and HbA1c were not affected by the training program. CONCLUSIONS: Elevated ADMA levels in patients with DM1, who have a high risk for developing cardiovascular disease, can be lowered to those of healthy persons by regular physical exercise. This favorable effect on ADMA is not sustained when training is discontinued.

Addressing unmet medical needs in type 2 diabetes: a narrative review of drugs under development.

The global burden of type 2 diabetes is increasing worldwide, and successful treatment of this disease needs constant provision of new drugs. Twelve classes of antidiabetic drugs are currently available, and many new drugs are under clinical development. These include compounds with known mechanisms of action but unique properties, such as once-weekly DPP4 inhibitors or oral insulin. They also include drugs with new mechanisms of action, the focus of this review. Most of these compounds are in Phase 1 and 2, with only a small number having made it to Phase 3 at this time. The new drug classes described include PPAR agonists/modulators, glucokinase activators, glucagon receptor antagonists, anti-inflammatory compounds, G-protein coupled receptor agonists, gastrointestinal peptide agonists other than GLP-1, apical sodium-dependent bile acid transporter (ASBT) inhibitors, SGLT1 and dual SGLT1/SGLT2 inhibitors, and 11beta- HSD1 inhibitors.

Weight loss reduces circulating asymmetrical dimethylarginine concentrations in morbidly obese women.

The endogenous nitric oxide-synthase inhibitor asymmetrical dimethyl-L-arginine (ADMA) is elevated in patients with increased risk for arteriosclerosis. Obesity is a risk factor for cardiovascular disease. We measured plasma ADMA concentrations in morbidly obese women before and after weight loss following gastroplastic surgery. ADMA and symmetrical dimethyl-L-arginine concentrations were analyzed by HPLC from 34 female patients (age 41 +/- 7 yr) with a body mass index (BMI) of 49 +/- 1 kg/m2 before and 14 months after vertical ring gastroplasty. Age-matched healthy women (BMI < 25 kg/m2; n = 24) were studied as controls. After gastroplastic surgery, BMI decreased to 34 +/- 1 kg/m2 in obese women (P < 0.00001), and ADMA concentrations were reduced from 1.06 +/- 0.06 micromol/liter at baseline to 0.81 +/- 0.04 micromol/liter after weight loss (P < 0.00001). Symmetrical dimethyl-L-arginine plasma levels were not affected. ADMA correlated with high-sensitivity C-reactive protein at baseline (r = 0.42; P < 0.05) and after weight loss (r = 0.56; P < 0.005). No association with blood pressure or plasma lipids could be observed. ADMA concentrations were lower in controls (0.68 +/- 0.04 micromol/liter; P < 0.05) compared with obese patients before or after weight reduction. The decrease of highly elevated ADMA concentrations in morbidly obese patients is paralleled by improvement of parameters associated with the metabolic syndrome after weight loss.