S. Kahl

Inhibition of 11β-HSD1 with RO5093151 for non-alcoholic fatty liver disease: a multicentre, randomised, double-blind, placebo-controlled trial

BACKGROUND The prevalence of non-alcoholic fatty liver disease is increasing worldwide and an effective and safe pharmacological treatment is needed. We investigated whether inhibition of 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1, also known as HSD11B1) by RO5093151 could safely and effectively decrease liver-fat content in patients with this disorder. METHODS We did this phase 1b trial at four centres in Germany and Austria. Participants with non-alcoholic fatty liver disease (defined as (1)H magnetic resonance spectroscopy liver-fat content >5·56%), insulin resistance (homoeostatic model assessment of insulin resistance [HOMA-IR] of at least 2·0 mmol/L·mU/L), BMI greater than 27 kg/m(2), and aged 35-65 years were randomly assigned by interactive voice response system in a 1:1 ratio, stratified for triglyceride concentration (<1·7 mmol/L or ≥1·7 mmol/L), to oral RO5093151 (200 mg twice daily) or matching placebo for 12 weeks. The main exclusion criteria were other liver diseases, aspartate aminotransferase or alanine aminotransferase concentrations of more than two and a half times the upper limit of normal, history of diabetes or bariatric surgery, and use of weight lowering drugs. Participants and investigators were masked to assignment throughout the study. The primary endpoint was change in liver-fat content from baseline to week 12. Efficacy analysis was by modified intention to treat, including all patients who received at least one dose of study drug and had a baseline and follow-up measurement of liver-fat content. Safety analyses included all patients who received at least one dose of study drug. This trial is registered with ClinicalTrials.gov, number NCT01277094. FINDINGS We did this trial between Jan 13, 2011, and March 28, 2012. 41 patients were randomly assigned to RO5093151 and 41 to placebo. 35 patients in the RO5093151 group and 39 in the placebo group were included in the efficacy analysis. Mean liver-fat content decreased in the RO5093151 group (from 16·75% [SD 8·67] to 14·28% [8·89]), but not in the placebo group (from 18·53% [10·00] to 18·46% [10·78], p=0·02 for between group difference). 26 participants (65%) in the RO5093151 group had adverse events, compared with 21 (53%) in the placebo group. The most common adverse events were gastrointestinal disorders (12 patients [30%] in the RO5093151 group vs seven [18%] in the placebo group), and infections and infestations (eight [20%] vs nine [23%]). Nervous system disorders occurred in significantly more patients in the RO5093151 group than in the placebo group (nine [23%] vs two [5%]; p=0·02); all other differences in adverse events were non-significant. One participant (3%) in the placebo group and three participants (8%) in the RO5093151 group had serious adverse events. All serious adverse events were deemed unrelated to study treatment. INTERPRETATION Inhibition of 11β-HSD1 by RO5093151 was effective and safe in reducing liver-fat content, suggesting that targeting of 11β-HSD1 might be a promising approach for the treatment of non-alcoholic fatty liver disease. FUNDING F Hoffmann-La Roche.

Comparison of liver fat indices for the diagnosis of hepatic steatosis and insulin resistance.

Context Hepatic steatosis, defined as increased hepatocellular lipid content (HCL), associates with visceral obesity and glucose intolerance. As exact HCL quantification by 1H-magnetic resonance spectroscopy (1H-MRS) is not generally available, various clinical indices are increasingly used to predict steatosis. Objective The purpose of this study was to test the accuracy of NAFLD liver fat score (NAFLD-LFS), hepatic steatosis index (HSI) and fatty liver index (FLI) against 1H-MRS and their relationships with insulin sensitivity and secretion. Design, Setting and Participants Ninety-two non-diabetic, predominantly non-obese humans underwent clinical examination, 1H-MRS and an oral glucose tolerance test (OGTT) to calculate insulin sensitivity and β-cell function. Accuracy of indices was assessed from the area under the receiver operating characteristic curve (AROC). Results Median HCL was 2.49% (0.62;4.23) and correlated with parameters of glycemia across all subjects. NAFLD-LFS, FLI and HSI yielded AROCs of 0.70, 0.72, and 0.79, respectively, and related positively to HCL, insulin resistance, fasting and post-load β-cell function normalized for insulin resistance. Upon adjustment for age, sex and HCL, regression analysis revealed that NAFLD-LFS, FLI and HSI still independently associated with both insulin sensitivity and β-cell function. Conclusion The tested indices offer modest efficacy to detect steatosis and cannot substitute for fat quantification by 1H-MRS. However, all indices might serve as surrogate parameters for liver fat content and also as rough clinical estimates of abnormal insulin sensitivity and secretion. Further validation in larger collectives such as epidemiological studies is needed.

Acute dietary fat intake initiates alterations in energy metabolism and insulin resistance

BACKGROUND. Dietary intake of saturated fat is a likely contributor to nonalcoholic fatty liver disease (NAFLD) and insulin resistance, but the mechanisms that initiate these abnormalities in humans remain unclear. We examined the effects of a single oral saturated fat load on insulin sensitivity, hepatic glucose metabolism, and lipid metabolism in humans. Similarly, initiating mechanisms were examined after an equivalent challenge in mice. METHODS. Fourteen lean, healthy individuals randomly received either palm oil (PO) or vehicle (VCL). Hepatic metabolism was analyzed using in vivo 13C/31P/1H and ex vivo 2H magnetic resonance spectroscopy before and during hyperinsulinemic-euglycemic clamps with isotope dilution. Mice underwent identical clamp procedures and hepatic transcriptome analyses. RESULTS. PO administration decreased whole-body, hepatic, and adipose tissue insulin sensitivity by 25%, 15%, and 34%, respectively. Hepatic triglyceride and ATP content rose by 35% and 16%, respectively. Hepatic gluconeogenesis increased by 70%, and net glycogenolysis declined by 20%. Mouse transcriptomics revealed that PO differentially regulates predicted upstream regulators and pathways, including LPS, members of the TLR and PPAR families, NF-&kgr;B, and TNF-related weak inducer of apoptosis (TWEAK). CONCLUSION. Saturated fat ingestion rapidly increases hepatic lipid storage, energy metabolism, and insulin resistance. This is accompanied by regulation of hepatic gene expression and signaling that may contribute to development of NAFLD. REGISTRATION. ClinicalTrials.gov NCT01736202. FUNDING. Germany: Ministry of Innovation, Science, and Research North Rhine–Westfalia, German Federal Ministry of Health, Federal Ministry of Education and Research, German Center for Diabetes Research, German Research Foundation, and German Diabetes Association. Portugal: Portuguese Foundation for Science and Technology, FEDER – European Regional Development Fund, Portuguese Foundation for Science and Technology, and Rede Nacional de Ressonância Magnética Nuclear.

Leukocyte Profiles Differ Between Type 1 and Type 2 Diabetes and Are Associated With Metabolic Phenotypes: Results From the German Diabetes Study (GDS)

OBJECTIVE Altered immune reactivity precedes and accompanies type 1 and type 2 diabetes. We hypothesized that the metabolic phenotype relates to the systemic cellular immune status. RESEARCH DESIGN AND METHODS A total of 194 metabolically well-controlled patients with type 1 diabetes (n = 62, mean diabetes duration 1.29 years) or type 2 diabetes (n = 132, 1.98 years) and 60 normoglycemic persons underwent blood sampling for automated white blood cell counting (WBC) and flow cytometry. Whole-body insulin sensitivity was measured with hyperinsulinemic-euglycemic clamp tests. RESULTS Patients with type 2 diabetes had higher WBC counts than control subjects along with a higher percentage of T cells and activated T helper (Th) and cytotoxic T (Tc) cells but lower proportions of natural killer (NK) cells. In type 1 diabetes, the percentage of activated Th and Tc cells was also higher compared with control subjects, whereas the ratio of regulatory T (Treg) cells to activated Th cells was lower, suggesting diminished regulatory capacity. Parameters of glycemic control related positively to Treg cells only in type 2 diabetes. Upon age, sex, and body mass adjustments, insulin sensitivity correlated positively with monocytes, while circulating lipids correlated positively with T cell subsets in type 1 diabetes. CONCLUSIONS Immune cell phenotypes showed distinct frequencies of occurrence in both diabetes types and associate with insulin sensitivity, glycemia, and lipidemia.

Variants in Genes Controlling Oxidative Metabolism Contribute to Lower Hepatic ATP Independent of Liver Fat Content in Type 1 Diabetes

Type 1 diabetes has been recently linked to nonalcoholic fatty liver disease (NAFLD), which is known to associate with insulin resistance, obesity, and type 2 diabetes. However, the role of insulin resistance and hyperglycemia for hepatic energy metabolism is yet unclear. To analyze early abnormalities in hepatic energy metabolism, we examined 55 patients with recently diagnosed type 1 diabetes. They underwent hyperinsulinemic-normoglycemic clamps with [6,6-2H2]glucose to assess whole-body and hepatic insulin sensitivity. Hepatic γATP, inorganic phosphate (Pi), and triglyceride concentrations (hepatocellular lipid content [HCL]) were measured with multinuclei magnetic resonance spectroscopy (31P/1H-MRS). Glucose-tolerant humans served as control (CON) (n = 57). Whole-body insulin sensitivity was 44% lower in patients than in age- and BMI-matched CON. Hepatic γATP was 15% reduced (2.3 ± 0.6 vs. 2.7 ± 0.6 mmol/L, P < 0.001), whereas hepatic Pi and HCL were similar in patients when compared with CON. Across all participants, hepatic γATP correlated negatively with glycemia and oxidized LDL. Carriers of the PPARG G allele (rs1801282) and noncarriers of PPARGC1A A allele (rs8192678) had 21 and 13% lower hepatic ATP concentrations. Variations in genes controlling oxidative metabolism contribute to a reduction in hepatic ATP in the absence of NAFLD, suggesting that alterations in hepatic mitochondrial function may precede diabetes-related liver diseases.

Amino Acid and Fatty Acid Levels Affect Hepatic Phosphorus Metabolite Content in Metabolically Healthy Humans

Objective Hepatic energy metabolism negatively relates to insulin resistance and liver fat content in patients with type 2 diabetes, but its role in metabolically healthy humans is unclear. We hypothesized that intrahepatocellular γ-adenosine triphosphate (γATP) and inorganic phosphate (Pi) concentrations exhibit similar associations with insulin sensitivity in nondiabetic, nonobese volunteers. Design A total of 76 participants underwent a four-point sampling, 75-g oral glucose tolerance test (OGTT), as well as in vivo31P/1H magnetic resonance spectroscopy. In 62 of them, targeted plasma metabolomic profiling was performed. Pearson correlation analyses were performed for the dependent variables γATP and Pi. Results Adjusted for age, sex, and body mass index (BMI), hepatic γATP and Pi related to 2-hour OGTT glucose (r = 0.25 and r = 0.27, both P < 0.05), and Pi further associated with nonesterified fatty acids (NEFAs; r = 0.28, P < 0.05). However, neither γATP nor Pi correlated with several measures of insulin sensitivity. Hepatic γATP correlated with circulating leucine (r = 0.42, P < 0.001) and Pi with C16:1 fatty acids palmitoleic acid and C16:1w5 (r = 0.28 and 0.30, respectively, P < 0.01), as well as with δ-9-desaturase index (r = 0.33, P < 0.05). Only the association of γATP with leucine remained important after correction for multiple testing. Leucine and palmitoleic acid, together with age, sex, and BMI, accounted for 26% and for 15% of the variabilities in γATP and Pi, respectively. Conclusions Specific circulating amino acids and NEFAs, but not measures of insulin sensitivity, partly affect hepatic phosphorus metabolites, suggesting mutual interaction between hepatic energy metabolism and circulating metabolites in nondiabetic humans.

Simplified analysis of acetaminophen glucuronide for quantifying gluconeogenesis and glycogenolysis using deuterated water

Measurement of acetaminophen glucuronide (AG) (2)H enrichment from deuterated water ((2)H2O) by (2)H nuclear magnetic resonance (NMR) analysis of its monoacetone glucose (MAG) derivative provides estimation of gluconeogenic and glycogenolytic contributions to endogenous glucose production (EGP). However, AG derivatization to MAG is laborious and unsuitable for high-throughput studies. An alternative derivative, 5-O-acetyl monoacetone glucuronolactone (MAGLA), was tested. Eleven healthy subjects ingested (2)H2O to 0.5% body water enrichment and 500 mg of acetaminophen. Plasma glucose and urinary glucuronide positional (2)H enrichments were measured by (2)H NMR spectroscopy of MAG and MAGLA, respectively. A Bland-Altman analysis indicated agreement at the 95% confidence level between glucose and glucuronide estimates.

Reduced expression of stearoyl-CoA desaturase-1, but not free fatty acid receptor 2 or 4 in subcutaneous adipose tissue of patients with newly diagnosed type 2 diabetes mellitus

BackgroundIn subcutaneous adipose tissue (SAT), higher stearoyl-CoA desaturase-1 (SCD1) expression has been related to improved insulin sensitivity in thiazolidinedione-treated type 2 diabetes mellitus patients. In animal models, deficiency of the free fatty acid receptor (FFAR) 2 associated with higher and FFAR4-deficiency with lower insulin sensitivity. We hypothesized that increased FFAR2 expression and reductions in FFAR4 and SCD1 expression in SAT of type 2 diabetes mellitus patients associate positively with insulin resistance and impaired beta cell function.MethodsTwenty-five type 2 diabetes mellitus patients and 25 glucose-tolerant humans (CON) matched for sex, age, and BMI underwent mixed-meal tests to assess insulin sensitivity (OGIS) and beta cell function (ΔAUC(C-peptide)0–180 min/ΔAUC(glucose)0–180 min) in a cross-sectional study. Gene and protein expression of SCD1 and FFAR2/4 were quantified in SAT biopsies.ResultsInsulin sensitivity was 14% and beta cell function 71% (both p < 0.001) lower in type 2 diabetes mellitus patients. In type 2 diabetes mellitus, SCD1 mRNA was fivefold (p < 0.001) and protein expression twofold (p < 0.01) lower. While FFAR2/4 mRNA and protein expression did not differ between groups, FFAR2 protein levels correlated negatively with beta cell function only in CON (r = −0.74, p < 0.01). However, neither SCD1 nor FFAR2/4 protein expression correlated with insulin sensitivity in both groups.ConclusionsType 2 diabetes patients have lower SCD1, which does not associate with insulin resistance. Only in non-diabetic humans, FFAR2 associated with impaired beta cell function.

Amino acids — lifesaver or killer in patients with diabetes?

Distinct circulating amino acids are suggested to modulate the risk of complications and mortality related to diabetes mellitus. These findings pave the way for future basic and clinical studies to gain new insights into the pathogenesis and treatment of diabetes mellitus.

Blutzuckersenkung durch den Phosphatbinder Sevelamer

Hintergrund. Sevelamer ist ein intestinal nicht resorbierbarer Phosphatbinder, der zur Behandlung der Hyperphosphatämie bei Patienten mit terminaler Niereninsuffizienz eingesetzt wird. Weitere Effekte von Sevelamer umfassen die Bindung von intestinalen Gallensäuren sowie positive Wirkungen auf den Glukoseund Lipidstoffwechsel. Durch die intestinale Bindung von Gallensäuren an Sevelamer werden diese dem enterohepatischen Kreislauf entzogen, wasmit einem kompensatorischen Anstieg der hepatischen Plasma-LowDensity Lipoprotein(LDL)-Clearance und der Umwandlung von Cholesterin in Gallensäuren einhergeht. Die den Glukosespiegel senkenden Mechanismen der intestinalen Gallensäurebindung sind bislang nicht vollständig verstanden. DieAutorenderhiervorgestelltenStudie stellten die Hypothese auf, dass der Einfluss vonSevelamer auf den enterohepatischen Gallensäurekreislauf eine veränderte Aktivierung der Gallensäurerezeptoren TGR5 (Takeda-G-Protein-Rezeptor-5) und FXR (Farnesoid X-Rezeptor)verursacht,mitnachfolgendenEffektenaufdieGlucagon-likePeptide 1(GLP1)-Sekretion und denGlukosemetabolismus.