Characteristics of hepatic insulin-sensitive nonalcoholic fatty liver disease

Plasma Metabolite Signatures in Male Carriers of Genetic Variants Associated with Non-Alcoholic Fatty Liver Disease

Both genetic and non-genetic factors are important in the pathophysiology of non-alcoholic fatty liver disease (NAFLD). The aim of our study was to identify novel metabolites and pathways associated with NAFLD by including both genetic and non-genetic factors in statistical analyses. We genotyped six genetic variants in the PNPLA3, TM6SF2, MBOAT7, GCKR, PPP1R3B, and HSD17B13 genes reported to be associated with NAFLD. Non-targeted metabolomic profiling was performed from plasma samples. We applied a previously validated fatty liver index to identify participants with NAFLD. First, we associated the six genetic variants with 1098 metabolites in 2 339 men without NAFLD to determine the effects of the genetic variants on metabolites, and then in 2 535 men with NAFLD to determine the joint effects of genetic variants and non-genetic factors on metabolites. We identified several novel metabolites and metabolic pathways, especially for PNPLA3, GCKR, and PPP1R38 variants relevant to the pathophysiology of NAFLD. Importantly, we showed that each genetic variant for NAFLD had a specific metabolite signature. The plasma metabolite signature was unique for each genetic variant, suggesting that several metabolites and different pathways are involved in the risk of NAFLD. The FLI index reliably identifies metabolites for NAFLD in large population-based studies.

Empagliflozin versus sitagliptin for ameliorating intrahepatic lipid content and tissue-specific insulin sensitivity in patients with early-stage type 2 diabetes with non-alcoholic fatty liver disease: A prospective randomized study

AIM

To compare the effects of sodium-glucose co-transporter-2 (SGLT2) inhibitors and dipeptidyl peptidase-4 inhibitors on ectopic fat accumulation and tissue-specific insulin sensitivity.

MATERIALS AND METHODS

This randomized controlled trial enrolled 44 patients with type 2 diabetes (T2D) and non-alcoholic fatty liver disease (NAFLD). They were randomly assigned to receive either empagliflozin 10 mg/day or sitagliptin 100 mg/day for 12 weeks. The primary endpoint was the change in intrahepatic lipid content (IHL) measured using proton magnetic resonance spectroscopy (¹ H-MRS). The secondary endpoints included intramuscular and extramuscular lipid content seen in ¹ H-MRS, body composition seen through dual-energy X-ray absorptiometry and tissue-specific insulin sensitivity shown through hyperinsulinaemic-euglycaemic clamp using stable isotopic glucose. Liver biopsy samples were pathologically evaluated at baseline.

RESULTS

At baseline, the mean duration of diabetes, HbA1c level and IHL were 3.7 years, 7.2% and 20.9%, respectively. The median NAFLD activity score was 3.0. IHL was significantly more decreased in the empagliflozin group than that in the sitagliptin group (between-group difference was -5.2% ± 1.1% and -1.9% ± 1.2%, respectively, (95% confidence interval); -3.3 (-6.5, -0.1), P = .044). However, there were no significant between-group differences in the change of insulin sensitivity in the liver, muscle or adipose tissues. Interestingly, hepatic insulin sensitivity was significantly increased only in the empagliflozin group and was significantly negatively associated with the change in IHL.

CONCLUSIONS

Empagliflozin significantly improves hepatic steatosis compared with sitagliptin, and this may protect against subsequent hepatic insulin resistance. Early administration of SGLT2 inhibitors is preferable for T2D patients with NAFLD.

Effect of quercetin and Abelmoschus esculentus (L.) Moench on lipids metabolism and blood glucose through AMPK-α in diabetic rats (HFD/STZ)

Phosphoenolpyruvate carboxykinase (PEPCK) is a key enzyme in the glyconeogenesis pathway. The AMP-activated protein kinase alpha (AMPK-α) pathway regulates PEPCK, which itself is activated by the AMP/ATP ratio and liver kinase B1 (KB1). The Abelmoschus esculentus (L.) Moench (okra) plant contains a large amount of quercetin that can function as an agonist or an antagonist. The aim of this study was to examine the effects of quercetin flavonoid and A. esculentus extract on the level of AMPK-α expression and associated metabolic pathways. The findings demonstrate that metformin, quercetin, and okra extract may significantly raise AMPK-α levels while significantly lowering PEPCK and hormone-sensitive lipase (HSL) levels, in addition to improving glucose and lipid profiles. By stimulating KB1, these substances increased AMPK-α activation. Additionally, AMPK-α activation improved insulin resistance and Glucose transporter type 4 (GLUT4) gene expression levels. Since AMPK-α maintains energy balance and its activity has not been reported to be inhibited so far, it could be a potent therapeutic target. PRACTICAL APPLICATIONS: The development of effective AMPK-α agonists and antagonists holds promise for the treatment of metabolic disorders like diabetes. Dietary polyphenols are a valuable source for developing new drugs. However, due to the lack of understanding of the underlying mechanisms of their effect on cells, their use in the treatment of diabetes is controversial. In addition to chemicals that have medicinal benefits, chemists are searching for less harmful substances. Using plants containing bioactive chemicals for this purpose can be a good alternative to chemical drugs.

UPLC-Orbitrap-MS/MS Combined With Biochemical Analysis to Determine the Growth and Development of Mothers and Fetuses in Different Gestation Periods on Tibetan Sow Model

Pregnancy is a complex and dynamic process, the physiological and metabolite changes of the mother are affected by different pregnancy stages, but little information is available about their changes and potential mechanisms during pregnancy, especially in blood and amniotic fluid. Here, the maternal metabolism rules at different pregnancy stages were investigated by using a Tibetan sow model to analyze the physiological hormones and nutrient metabolism characteristics of maternal serum and amniotic fluid as well as their correlations with each other. Our results showed that amniotic fluid had a decrease (P < 0.05) in the concentrations of glucose, insulin and hepatocyte growth factor as pregnancy progressed, while maternal serum exhibited the highest concentrations of glucose and insulin at 75 days of gestation (P < 0.05), and a significant positive correlation (P < 0.05) between insulin and citric acid. Additionally, T4 and cortisol had the highest levels during late gestation (P < 0.05). Furthermore, metabolomics analysis revealed significant enrichment in the citrate cycle pathway and the phenylalanine/tyrosine/tryptophan biosynthesis pathway (P < 0.05) with the progress of gestation. This study clarified the adaptive changes of glucose, insulin and citric acid in Tibetan sows during pregnancy as well as the influence of aromatic amino acids, hepatocyte growth factor, cortisol and other physiological indicators on fetal growth and development, providing new clues for the normal development of the mother and the fetus, which may become a promising target for improving the well-being of pregnancy.

Identification of metabolomic profile related to adult Fontan pathophysiology

Background

Metabolic disorders are important pathophysiologies that can cause multiple organ dysfunction and worsen prognosis in Fontan patients. This study aimed to comprehensively evaluate the metabolomic profile of adult Fontan patients and characterize its pathophysiology in relation to 2 control groups.

Methods and Results

We performed metabolomic analysis of 31 plasma samples using capillary electrophoresis time-of-flight mass spectrometry. This observational cross-sectional study compared plasma metabolites of 14 heterogeneous adult Fontan patients with those of control groups, including 9 patients with congenital heart disease after biventricular repair and 8 normal healthy controls. Fontan patients exhibited significant differences in intermediate metabolite concentrations related to glycolysis, the tricarboxylic acid (TCA) cycle, and the urea cycle. The plasma concentrations of lactic acid, 2-oxoglutarate, isocitric acid, malic acid, cis-aconitic acid, arginine, citrulline, and the ratio of ornithine/citrulline showed significantly differences among the groups. Multiple logistic regression analysis with a stepwise selection-elimination method identified 2-oxoglutaric acid (odds ratio [OR] 1.98, 95% confidence interval [CI] 1.05–3.76) and cis-aconitic acid (OR 2.69, 95% CI 1.04–6.99) as independently associated with Fontan patients. After adjustment for the covariates of age and gender, 2-oxoglutaric acid (OR 1.97, 95% CI 0.98–3.93) and cis-aconitic acid (OR 3.88, 95% CI 0.99–15.2) showed remarkable relationships with Fontan patients.

Conclusions

The present findings suggest that abnormalities in the TCA cycle and amino acid metabolism are distinguishing features in the pathophysiology of Fontan patients. Future metabolomic studies will assist in developing biomarkers for the early prediction of “silent” Fontan pathophysiologies.

Insulin resistance and muscle weakness are synergistic risk factors for silent lacunar infarcts: the Bunkyo Health Study

Insulin resistance and muscle weakness are risk factors for silent lacunar infarcts (SLI), but it is unclear whether they are still independent risk factors when adjusted for each other. In addition, the effect of their combination on SLI is completely unknown. We evaluated SLI, insulin sensitivity, and knee extensor muscle strength by magnetic resonance imaging, PREDIM, and dynamometer, respectively, in 1531 elderly people aged 65–84 years living in an urban area of Tokyo. Among the study subjects, 251 (16.4%) had SLI. Impaired insulin sensitivity (High; 1.00 [reference], Medium; 1.53 [95% confidence interval (CI) 0.94–2.48], Low; 1.86 [1.02–3.39], p for trend 0.047) and reduced muscle strength (High; 1.00 [reference], Medium; 1.40 [0.98–2.02], Low; 1.49 [1.04–2.15], p for trend 0.037) were independently associated with increased risk for SLI in the fully adjusted model. In terms of combined, subjects classified as having the lowest insulin sensitivity and lowest strength were 4.33 times (95% CI 1.64–11.45) more likely to have a SLI than those classified as having the highest insulin sensitivity and highest strength. Impaired insulin sensitivity and reduced muscle strength were independently associated with higher risk of SLI in elderly subjects, and their combination synergistically increased this risk.

Chronotherapeutic efficacy of suvorexant on sleep quality and metabolic parameters in patients with type 2 diabetes and insomnia

AIMS

This study aimed to assess the chronotherapeutic efficacy of suvorexant on subjective sleep parameters and metabolic parameters in patients with type 2 diabetes and insomnia.

METHODS

Thirteen patients with type 2 diabetes who met the Pittsburg Sleep Quality index criteria for primary insomnia took suvorexant 20 mg/day (15 mg/day for ≥65 years) for 14 ± 2 weeks. The following parameters were assessed before and after the treatment: sleep diary for sleep duration and quality (i.e., sleep onset latency, waking after sleep onset, and sleep efficiency [sSE]), Insomnia Severity Index, clinical and biochemical data, continuous glucose monitoring (CGM), and validated self-administered questionnaire on food intake.

RESULTS

Suvorexant significantly improved sSE, abdominal circumference, and sucrose intake (all p < 0.05), but did not change HbA1c, CGM parameters, or body weight. Correlation analysis revealed that changes in sSE were associated with those in HbA1c and body weight (r = -0.61 and r = -0.66, respectively; both p < 0.05).

CONCLUSIONS

Suvorexant significantly improved sleep quality and obesity-associated parameters in patients with type 2 diabetes in 14 weeks. Improvements in sleep quality were associated with improvements in glycemic control. Sleep disorder treatment using suvorexant may provide metabolic benefits for patients with type 2 diabetes.

Both higher fitness level and higher current physical activity level may be required for intramyocellular lipid accumulation in non-athlete men

Accumulation of intramyocellular lipid (IMCL) is observed in individuals with insulin resistance as well as insulin-sensitive endurance athletes with high peak oxygen consumption (VO₂peak), which is called the athlete’s paradox. It remains unclear whether non-athletes with higher fitness levels have IMCL accumulation and higher insulin sensitivity in general. In this study, we investigated the association between IMCL accumulation and muscle insulin sensitivity (M-IS) in subjects with high or low VO₂peak. We studied 61 nonobese (BMI, 23 to 25 kg/m²), non-athlete Japanese men. We divided the subjects into four groups based on the median value of VO₂peak and IMCL in the soleus muscle. We evaluated M-IS using a two-step hyperinsulinemic-euglycemic clamp. Among subjects with higher VO₂peak (n = 32), half of those (n = 16) had lower IMCL levels. Both High-VO₂peak groups had higher M-IS than the Low-VO₂peak groups. On the other hand, M-IS was comparable between the High-VO₂peak/High-IMCL and High-VO₂peak/Low-IMCL groups, whereas the High-VO₂peak/High-IMCL group had IMCL levels that were twice as high as those in the High-VO₂peak/Low-IMCL group. On the other hand, the High-VO₂peak/High-IMCL group had significantly higher physical activity levels (approximately 1.8-fold) than the other three groups. In conclusion, in nonobese, non-athlete Japanese men, subjects with higher VO₂peak and higher IMCL had higher physical activity levels. IMCL accumulation is not associated with insulin resistance in individuals with higher or lower fitness levels.

Plasma Krebs Cycle Intermediates in Nonalcoholic Fatty Liver Disease

Nonalcoholic liver disease (NAFLD) is manifested with a wide spectrum of clinical symptoms and is closely associated with the metabolic syndrome, inflammation, and mitochondrial dysfunction. Although the mechanism of mitochondrial dysfunction in NAFLD is still not fully elucidated, multiple studies have demonstrated evidence of molecular, biochemical, and biophysical mitochondrial abnormalities in NAFLD. Given the association between NAFLD and mitochondrial dysfunction, the aim of this study is to analyze circulating levels of Krebs cycle intermediates in a cohort of NAFLD-affected individuals and matching healthy controls and to correlate our findings with the liver function metrics. Standard serum biochemistry and Krebs cycle intermediates were analyzed in NAFLD (n = 22) and matched control (n = 67) cohorts. Circulating levels of isocitrate and citrate were significantly (p < 0.05) elevated in the NAFLD cohort of patients. The area under the curve (AUROC) for these two metabolites exhibited a moderate clinical utility. Correlations between plasma Krebs cycle intermediates and standard clinical plasma metrics were explored by Pearson’s correlation coefficient. The data obtained for plasma Krebs cycle intermediates suggest pathophysiological insights that link mitochondrial dysfunction with NAFLD. Our findings reveal that plasma isocitrate and citrate can discriminate between normal and NAFLD cohorts and can be utilized as noninvasive markers of mitochondrial dysfunction in NAFLD. Future studies with large populations at different NAFLD stages are warranted.

Whole hepatic lipid volume quantification and color mapping by multi-slice and multi-point magnetic resonance imaging

AIM

Current approaches for hepatic steatosis assess only a small point within the liver and might cause inaccuracy for longitudinal observation. We aimed to establish a reliable non-invasive method for whole hepatic lipid content evaluation.

METHODS

A total of 52 patients with hepatic steatosis underwent liver biopsy. Hepatic lipid content was assessed by Dixon in-phase/out-of-phase magnetic resonance imaging and proton magnetic resonance spectroscopy. Using multi-slice and multi-point magnetic resonance imaging, we calculated the lipid intensity of every voxel throughout the liver and showed the color-mapped lipid distributions. This new analysis could also quantify the whole hepatic lipid and whole liver volumes absolutely. The diagnostic performance of hepatic lipid content between the new analysis and proton magnetic resonance spectroscopy methods was compared by receiver operating characteristic curve analysis referring to the steatosis scores of the liver biopsy.

RESULTS

Areas under the receiver operating characteristic for the diagnosis of steatosis scores ≥1, ≥2, and ≥3 using magnetic resonance imaging and proton magnetic resonance spectroscopy were 0.86 (95% confidence interval [CI] 0.70-1.00) and 0.98 (95% CI 0.93-1.00), 0.94 (95% CI 0.87-1.00) and 0.93 (95% CI 0.86-1.00), and 0.95 (95% CI 0.89-1.00) and 0.97 (95% CI 0.93-1.00), respectively, showing comparable diagnostic accuracies. However, color mapping showed some inconsistencies between the methods.

CONCLUSIONS

We described a non-invasive and repeatable evaluation method of whole hepatic lipid accumulation with absolute quantification and color mapping. Hepatic steatosis was accurately evaluated regardless of heterogeneous lipid accumulation. The whole hepatic lean volume, reflecting the hepatic parenchymal condition, can also be determined by this method.

Rationale, Design for the ASSET Study: A Prospective Randomized Study Comparing Empagliflozin's Effect to Sitagliptin on Cardiac Fat Accumulation/Function in Patients with Type 2 Diabetes

INTRODUCTION

Ectopic fat accumulation has been found to play a pathophysiological role in insulin resistance, type 2 diabetes (T2DM), and coronary artery diseases. Findings from a number of previous studies suggest that sodium glucose cotransporter 2 (SGLT2) inhibitors reduce lipid accumulation, including myocardial and pericardial fat, while dipeptidyl peptidase 4 (DPP4) inhibitors suppress ectopic lipid accumulation and improve cardiac function. However, a clinical study that precisely explains and compares the efficacy of SGLT2 inhibitors and DPP4 inhibitors on cardiac fat accumulation has not been performed. Moreover, the association between cardiac fat accumulation and cardiac function or metabolic changes, such as tissue-specific insulin resistance, remains unclear. It is our intention to conduct the first study to assess the effects of empagliflozin compared to sitagliptin in reducing ectopic fat accumulation, specifically pericardial fat, and its association with improvement in cardiac function and tissue-specific insulin sensitivity.

METHODS

We have designed a prospective, randomized open-label, and blinded-endpoint study with the intention to enroll 44 Japanese patients with T2DM. The patients are to be divided them into two groups, an empagliflozin group and an sitagliptin group, with the former to be supplemented with empagliflozin 10 mg and the latter to be supplemented with sitagliptin 100 mg, both groups for 12 weeks. The primary endpoint of the study is the change in the amount of pericardial fat. The secondary endpoints are the changes in the amount of intracellular fat in the myocardium, cardiac function, tissue-specific insulin sensitivity, fatty acid metabolism in myocardial tissue, assessed by parameters of iodine-123-β-methyl-iodophenyl pentadecanoic acid myocardial scintigraphy, blood and urine biomarkers, and lifestyle evaluation.

PLANNED OUTCOMES

The results of this study will be available in 2020. The aim of this study is to provide an effective treatment strategy for patients with T2DM by considering cardiac fat accumulation, cardiac function, and insulin resistance.

FUNDING

Boehringer Ingelheim & Eli Lilly and Company Diabetes Alliance.

TRIAL REGISTRATION

University Hospital Medical Information Network Clinical Trial Registry: UMIN000026340.

Efficacy of intermittent empagliflozin supplementation on dietary self-management and glycaemic control in patients with poorly controlled type 2 diabetes: A 24-week randomized controlled trial

AIMS

To explore the effects of intermittent use of empagliflozin, a sodium-glucose co-transporter-2 inhibitor, on dietary self-management and glycaemic control in patients with inadequately controlled type 2 diabetes.

MATERIALS AND METHODS

We conducted a prospective, randomized, open-label, blinded-endpoint, parallel-group, comparative clinical trial of 50 patients with type 2 diabetes, treated with no more than three oral antidiabetic drugs (glycated haemoglobin [HbA1c] ≥52 mmol/mol but <86 mmol/mol). The participants were randomized to take 10 mg/d empagliflozin either every day (regular group, n = 25) or on the day on which they considered they had overeaten (intermittent group, n = 25) for 24 weeks. We limited empagliflozin prescription to half of the required period in the intermittent group. The primary endpoint was change in HbA1c at the end of the 24-week treatment period relative to baseline. The secondary outcomes included changes in body weight, daily energy intake and diabetes treatment-related quality of life (QoL). Energy intake was assessed using a diet-specific validated questionnaire rather than actual assessments of food intake.

RESULTS

The intake rate of empagliflozin was 96.7 ± 7.2% for the regular group and 45.7 ± 7.0% for the intermittent group. Interestingly, ΔHbA1c was identical in the two groups (-0.64 ± 0.19% and - 0.65 ± 0.17%, respectively). Body weight decreased (-2.72 ± 0.52 and - 1.50 ± 0.45 kg, respectively) and diabetes treatment-related QoL increased significantly from baseline in both groups. Energy intake, however, decreased significantly only in the intermittent group (-221.0 ± 108.3 kcal/d).

CONCLUSIONS

Intermittent empagliflozin supplementation is a useful therapeutic option that empowers dietary self-management, improves glycaemic control and is accompanied by body weight loss and an increase in diabetes treatment-related QoL in patients with inadequately controlled type 2 diabetes.

Postprandial metabolomics: GC-MS analysis reveals differences in organic acid profiles of impaired fasting glucose individuals in response to highland barley loads

The HB load producing low postprandial glucose and insulin responses brings about several alterations in organic acids.

Galangin, a dietary flavonoid, ameliorates hyperglycaemia and lipid abnormalities in rats with streptozotocin-induced hyperglycaemia

CONTEXT

Galangin, a natural flavonoid, is found in honey and Alpinia officinarum Hance (Zingiberaceae). Galangin has antiviral, antimicrobial, antidiabetic and anticancer properties, without side effects. The effects of galangin on hyperglycaemia and lipid abnormalities are not known.

OBJECTIVE

To elucidate the effectiveness of galangin on hyperglycaemia-associated complications and lipid changes in rats with streptozotocin (STZ)-induced hyperglycaemia.

MATERIALS AND METHODS

Diabetes was induced in adult Wistar rats by administering 40 mg/kg of STZ. In our previous study, galangin had no toxicity at concentrations up to 320 mg/kg. Therefore three doses of galangin (4, 8 or 16 mg/kg BW) or glibenclamide (600 µg/kg BW) were administered daily to diabetic rats orally for 45 days.

RESULTS

Diabetic rats showed a significant (p < 0.05) increased levels of plasma glucose (281.10 mg/dL) and decreased levels of insulin (6.01 μU/mL). Additionally, diabetic rats showed a significant (p < 0.05) increased levels of plasma lipid profiles such as total cholesterol (149.05 mg/dL), triglycerides (143.28 mg/dL), free fatty acids (139.37 mg/dL), phospholipids (127.53 mg/dL), plasma low-density lipoprotein-cholesterol (98.72 mg/dL), plasma very low-density lipoprotein-cholesterol (28.65 mg/dL), and significant (p < 0.05) decreased in plasma high-density lipoprotein-cholesterol (21.68 mg/dL). When galangin was administered to the hyperglycaemic rats, plasma glucose and insulin levels and lipid profiles reverted to levels similar to those in healthy control rats.

DISCUSSION AND CONCLUSIONS

Administration of galangin reduced hyperlipidaemia related to the risk of diabetic complications and could be beneficial for diabetic hyperlipidaemic patients. Further work detailing its mechanism-of-action for improving hyperglycaemic-associated lipid abnormalities is needed.

Mechanisms of sleep deprivation-induced hepatic steatosis and insulin resistance in mice

Sleep deprivation is associated with increased risk for type 2 diabetes mellitus. However, the underlying mechanisms of sleep deprivation-induced glucose intolerance remain elusive. The aim of this study was to investigate the mechanisms of sleep deprivation-induced glucose intolerance in mice with a special focus on the liver. We established a mouse model of sleep deprivation-induced glucose intolerance using C57BL/6J male mice. A single 6-h sleep deprivation by the gentle handling method under fasting condition induced glucose intolerance. Hepatic glucose production assessed by a pyruvate challenge test was significantly increased, as was hepatic triglyceride content (by 67.9%) in the sleep deprivation group, compared with freely sleeping control mice. Metabolome and microarray analyses were used to evaluate hepatic metabolites and gene expression levels and to determine the molecular mechanisms of sleep deprivation-induced hepatic steatosis. Hepatic metabolites, such as acetyl coenzyme A, 3β-hydroxybutyric acid, and certain acylcarnitines, were significantly increased in the sleep deprivation group, suggesting increased lipid oxidation in the liver. In contrast, fasted sleep-deprived mice showed that hepatic gene expression levels of elongation of very long chain fatty acids-like 3, lipin 1, perilipin 4, perilipin 5, and acyl-CoA thioesterase 1, which are known to play lipogenic roles, were 2.7, 4.5, 3.7, 2.9, and 2.8 times, respectively, those of the fasted sleeping control group, as assessed by quantitative RT-PCR. Sleep deprivation-induced hepatic steatosis and hepatic insulin resistance seem to be mediated through upregulation of hepatic lipogenic enzymes.

The anorexigenic peptide neurotensin relates to insulin sensitivity in obese patients after BPD or RYGB metabolic surgery

Neurotensin is a peptide with effects on appetite and intestinal lipid absorption. Experimental data suggest a role in glucose homeostasis, while human data is missing. Here, 20 morbidly obese subjects either underwent biliopancreatic diversion with duodenal switch (BPD), or Roux-en-Y gastric bypass (RYGB) in a randomized fashion. Before and 1 year after surgery, anthropometric data, body composition, clinical biochemistry, insulin sensitivity by means of euglycemic hyperinsulinemic clamps (HEC) and fasting plasma proneurotensin 1-117 were analyzed. Plasma proneurotensin increased significantly more 1 year after BDP than RYGB (P = 0.028), while weight loss was comparable. After metabolic surgery, proneurotensin correlated positively with insulin sensitivity (M-value) (r = 0.55, P < 0.001), while an inverse relationship with fasting glucose, HOMA-IR and HbA1c was observed (P < 0.05 for all components). After adjustment for age and gender, proneurotensin and BMI remained independently related with delta of M-value (β = 0.46 and β = 0.51, P < 0.05, resp.). From these data we conclude that proneurotensin positively correlates with insulin sensitivity uniquely after weight loss induced by metabolic surgery in humans. BDP leads to a stronger increase in the anorexigenic peptide compared to RYGB.