Gastric Bypass vs Diet and Cardiovascular Risk Factors: A Nonrandomized Controlled Trial.

Importance: Roux-en-Y gastric bypass (RYGB) is associated with reduced cardiovascular (CV) risk factors, morbidity, and mortality. Whether these effects are specifically induced by the surgical procedure or the weight loss is unclear. Objective: To compare 6-week changes in CV risk factors in patients with obesity undergoing matching caloric restriction and weight loss by RYGB or a very low-energy diet (VLED). Design, Setting, and Participants: This nonrandomized controlled study (Impact of Body Weight, Low Calorie Diet, and Gastric Bypass on Drug Bioavailability, Cardiovascular Risk Factors, and Metabolic Biomarkers [COCKTAIL]) was conducted at a tertiary care obesity center in Norway. Participants were individuals with severe obesity preparing for RYGB or a VLED. Recruitment began February 26, 2015; the first patient visit was on March 18, 2015, and the last patient visit (9-week follow-up) was on August 9, 2017. Data were analyzed from April 30, 2021, through June 29, 2023. Interventions: VLED alone for 6 weeks or VLED for 6 weeks after RYGB; both interventions were preceded by 3-week LED. Main Outcomes and Measures: Between-group comparisons of 6-week changes in CV risk factors. Results: Among 78 patients included in the analyses, the mean (SD) age was 47.5 (9.7) years; 51 (65%) were women, and 27 (35%) were men. Except for a slightly higher mean (SD) body mass index of 44.5 (6.2) in the RYGB group (n = 41) vs 41.9 (5.4) in the VLED group (n = 37), baseline demographic and clinical characteristics were similar between groups. Major atherogenic blood lipids (low-density lipoprotein cholesterol, non-high-density lipoprotein cholesterol, apolipoprotein B, lipoprotein[a]) were reduced after RYGB in comparison with VLED despite a similar fat mass loss. Mean between-group differences were -17.7 mg/dL (95% CI, -27.9 to -7.5), -17.4 mg/dL (95% CI, -29.8 to -5.0) mg/dL, -9.94 mg/dL (95% CI, -15.75 to -4.14), and geometric mean ratio was 0.55 U/L (95% CI, 0.42 to 0.72), respectively. Changes in glycemic control and blood pressure were similar between groups. Conclusions and Relevance: This study found that clinically meaningful reductions in major atherogenic blood lipids were demonstrated after RYGB, indicating that RYGB may reduce CV risk independent of weight loss. Trial Registration: ClinicalTrials.gov Identifier: NCT02386917.

Mortality in relation to diabetes remission in Swedish Obese Subjects -a prospective cohort study.

BACKGROUND: People with obesity and type 2 diabetes (T2D) have reduced life expectancy, partly explained by increased risk of cardiovascular diseases and cancer. Here, we examined whether 2-year diabetes remission after bariatric surgery or usual care is associated with long-term mortality. MATERIALS AND METHODS: This report includes 586 participants with obesity and concomitant T2D from the prospective Swedish Obese Subjects (SOS) cohort study; 338 underwent bariatric surgery and 248 received usual obesity care. At inclusion, age was 37-60 years and BMI ≥34 kg/m2 in men and ≥38 kg/m2 in women. Median follow-up was 26.2 years (interquartile range 22.7-28.7). Diabetes status was determined using self-reported data on diabetes medication and in-study measures of blood glucose and HbA1c. The study was cross-linked to Swedish national registers for data on morbidity, death, and emigration. RESULTS: Overall, 284 participants, 71.9% of surgery and 16.5% of usual care patients, were in remission at the 2-year examination. During follow-up, mortality rates were 16.6 deaths per 1000 person-years (95% CI:13.7-20.1) in the remission subgroup and 26.0 deaths per 1000 person-years (95% CI:22.2-30.4) in the non-remission subgroup (adjusted hazard ratio (HRadj)=0.71, 95% CI:0.54-0.95, P=0.019). The adjusted median life expectancy in the remission subgroup was 2.5 years (95% CI:0.3-4.7) longer than in the non-remission subgroup. Specifically, remission was associated with decreased cardiovascular mortality (sub-HRadj=0.54, 95% CI:0.35-0.85, P=0.008), but no detectable association with cancer mortality was found (sub-HRadj=1.06, 95% CI:0.60-1.86), P=0.841). CONCLUSION: In this post-hoc analysis of data from the SOS study, patients who achieved short-term diabetes remission had increased life expectancy and decreased cardiovascular death over up to 32 years of follow-up. Future studies should confirm these findings.

Oral Drug Dosing After Gastric Bypass and Diet-Induced Weight Loss: Simpler Than We Think? Lessons Learned From the COCKTAIL Study.

This article summarizes the lessons learned from the COCKTAIL study: an open, three-armed, single-center study including patients with obesity scheduled for treatment with Roux-en-Y gastric bypass (RYGB) or nonsurgical calorie restriction, and a normal- to overweight control group. The clinical implications of the results from multiple peer-reviewed articles describing the effects of RYGB, severe caloric restriction, weight loss, and type 2 diabetes on the in vivo activity and protein expression of drug-metabolizing enzymes (cytochrome P450 (CYP) 1A2, 2C9, 2C19, and 3A) and transporters (DMETs; organic anion-transporting polypeptide (OATP) 1B1 and P-glycoprotein (P-gp)) are discussed in the perspective of three clinically relevant questions: (1) How should clinicians get the dose right in patients after RYGB? (2) Will drug disposition in patients with obesity be normalized after successful weight loss? (3) Are dose adjustments needed according to obesity and diabetes status? Overall, RYGB seems to have a lower impact on drug disposition than previously assumed, but clinicians should pay close attention to drugs with a narrow therapeutic range or where a high maximum drug concentration may be problematic. Whether obesity-related alterations of DMETs normalize with substantial weight loss depends on the DMET in question. Obesity and diabetes downregulate the in vivo activity of CYP2C19 and CYP3A (only obesity) but whether substrate drugs should be dose adjusted is also dependent on other factors that influence clearance, that is, liver blood flow and protein binding. Finally, we recommend frequent and individualized follow-up due to high inter- and intraindividual variability in these patients, particularly following RYGB.

Taking a shortcut: what mechanisms do fish use?

Path integration is a powerful navigational mechanism whereby individuals continuously update their distance and angular vector of movement to calculate their position in relation to their departure location, allowing them to return along the most direct route even across unfamiliar terrain. While path integration has been investigated in several terrestrial animals, it has never been demonstrated in aquatic vertebrates, where movement occurs through volumetric space and sensory cues available for navigation are likely to differ substantially from those in terrestrial environments. By performing displacement experiments with Lamprologus ocellatus, we show evidence consistent with fish using path integration to navigate alongside other mechanisms (allothetic place cues and route recapitulation). These results indicate that the use of path integration is likely to be deeply rooted within the vertebrate phylogeny irrespective of the environment, and suggests that fish may possess a spatial encoding system that parallels that of mammals.

Digoxin Pharmacokinetics in Patients with Obesity Before and After a Gastric Bypass or a Strict Diet Compared with Normal Weight Individuals.

BACKGROUND AND OBJECTIVE: Several drugs on the market are substrates for P-glycoprotein (P-gp), an efflux transporter highly expressed in barrier tissues such as the intestine. Body weight, weight loss, and a Roux-en-Y gastric bypass (RYGB) may influence P-gp expression and activity, leading to variability in the drug response. The objective of this study was therefore to investigate digoxin pharmacokinetics as a measure of the P-gp phenotype in patients with obesity before and after weight loss induced by an RYGB or a strict diet and in normal weight individuals. METHODS: This study included patients with severe obesity preparing for an RYGB (n = 40) or diet-induced weight loss (n = 40) and mainly normal weight individuals scheduled for a cholecystectomy (n = 18). Both weight loss groups underwent a 3-week low-energy diet (<1200 kcal/day) followed by an additional 6 weeks of <800 kcal/day induced by an RYGB (performed at week 3) or a very-low-energy diet. Follow-up time was 2 years, with four digoxin pharmacokinetic investigations at weeks 0, 3, and 9, and year 2. Hepatic and jejunal P-gp levels were determined in biopsies obtained from the patients undergoing surgery. RESULTS: The RYGB group and the diet group had a comparable weight loss in the first 9 weeks (13 ± 2.3% and 11 ± 3.6%, respectively). During this period, we observed a minor increase (16%) in the digoxin area under the concentration-time curve from zero to infinity in both groups: RYGB: 2.7 µg h/L [95% confidence interval (CI) 0.67, 4.7], diet: 2.5 µg h/L [95% CI 0.49, 4.4]. In the RYGB group, we also observed that the time to reach maximum concentration decreased after surgery: from 1.0 ± 0.33 hours at week 3 to 0.77 ± 0.08 hours at week 9 (-0.26 hours [95% CI -0.47, -0.05]), corresponding to a 25% reduction. Area under the concentration-time curve from zero to infinity did not change long term (week 0 to year 2) in either the RYGB (1.1 µg h/L [-0.94, 3.2]) or the diet group (0.94 µg h/L [-1.2, 3.0]), despite a considerable difference in weight loss from baseline (RYGB: 30 ± 7%, diet: 3 ± 6%). At baseline, the area under the concentration-time curve from zero to infinity was -5.5 µg h/L [95% CI -8.5, -2.5] (-26%) lower in patients with obesity (RYGB plus diet) than in normal weight individuals scheduled for a cholecystectomy. Further, patients undergoing an RYGB had a 0.05 fmol/µg [95% CI 0.00, 0.10] (29%) higher hepatic P-gp level than the normal weight individuals. CONCLUSIONS: Changes in digoxin pharmacokinetics following weight loss induced by a pre-operative low-energy diet and an RYGB or a strict diet (a low-energy diet plus a very-low-energy diet) were minor and unlikely to be clinically relevant. The lower systemic exposure of digoxin in patients with obesity suggests that these patients may have increased biliary excretion of digoxin possibly owing to a higher expression of P-gp in the liver.

Effects of dapagliflozin and dapagliflozin-saxagliptin on erythropoiesis, iron and inflammation markers in patients with type 2 diabetes and chronic kidney disease: data from the DELIGHT trial.

BACKGROUND: This post-hoc analysis of the DELIGHT trial assessed effects of the SGLT2 inhibitor dapagliflozin on iron metabolism and markers of inflammation. METHODS: Patients with type 2 diabetes and albuminuria were randomized to dapagliflozin, dapagliflozin and saxagliptin, or placebo. We measured hemoglobin, iron markers (serum iron, transferrin saturation, and ferritin), plasma erythropoietin, and inflammatory markers (urinary MCP-1 and urinary/serum IL-6) at baseline and week 24. RESULTS: 360/461 (78.1%) participants had available biosamples. Dapagliflozin and dapagliflozin-saxagliptin, compared to placebo, increased hemoglobin by 5.7 g/L (95%CI 4.0, 7.3; p < 0.001) and 4.4 g/L (2.7, 6.0; p < 0.001) and reduced ferritin by 18.6% (8.7, 27.5; p < 0.001) and 18.4% (8.7, 27.1; p < 0.001), respectively. Dapagliflozin reduced urinary MCP-1/Cr by 29.0% (14.6, 41.0; p < 0.001) and urinary IL-6/Cr by 26.6% (9.1, 40.7; p = 0.005) with no changes in other markers. CONCLUSIONS: Dapagliflozin increased hemoglobin and reduced ferritin and urinary markers of inflammation, suggesting potentially important effects on iron metabolism and inflammation. TRIAL REGISTRATION: ClinicalTrials.gov NCT02547935.

Proteome deconvolution of liver biopsies reveals hepatic cell composition as an important marker of fibrosis.

Human liver tissue is composed of heterogeneous mixtures of different cell types and their cellular stoichiometry can provide information on hepatic physiology and disease progression. Deconvolution algorithms for the identification of cell types and their proportions have recently been developed for transcriptomic data. However, no method for the deconvolution of bulk proteomics data has been presented to date. Here, we show that proteomes, which usually contain less data than transcriptomes, can provide useful information for cell type deconvolution using different algorithms. We demonstrate that proteomes from defined mixtures of cell lines, isolated primary liver cells, and human liver biopsies can be deconvoluted with high accuracy. In contrast to transcriptome-based deconvolution, liver tissue proteomes also provided information about extracellular compartments. Using deconvolution of proteomics data from liver biopsies of 56 patients undergoing Roux-en-Y gastric bypass surgery we show that proportions of immune and stellate cells correlate with inflammatory markers and altered composition of extracellular matrix proteins characteristic of early-stage fibrosis. Our results thus demonstrate that proteome deconvolution can be used as a molecular microscope for investigations of the composition of cell types, extracellular compartments, and for exploring cell-type specific pathological events. We anticipate that these findings will allow the refinement of retrospective analyses of the growing number of proteome datasets from various liver disease states and pave the way for AI-supported clinical and preclinical diagnostics.

Life expectancy after bariatric surgery or usual care in patients with or without baseline type 2 diabetes in Swedish Obese Subjects.

OBJECTIVES: To determine life expectancy and causes of death after bariatric surgery in relation to baseline type 2 diabetes (T2D) in the prospective, Swedish Obese Subjects study. METHODS: The study included 2010 patients with obesity who underwent bariatric surgery and 2037 matched controls, eligible for surgery. The surgery group underwent gastric bypass (n = 265), banding (n = 376), or vertical banded gastroplasty (n = 1369). The control group (n = 2037) received usual obesity care. Causes of death were obtained from the Swedish Cause of Death Register, case sheets and autopsy reports, in patients with baseline T2D (n = 392 surgery patients/n = 305 controls) or non-T2D (n = 1609 surgery patients/n = 1726 controls) during a median follow-up 26 years. RESULTS: In T2D and non-T2D subgroups, bariatric surgery was associated with increased life expectancy (2.1, 95% confidence interval (95% CI) 0.2-4.0; and 1.6, 0.5-2.7 years, respectively) and reduced overall mortality (adjusted hazard ratio (adjHR) = 0.77, 95% CI: 0.61-0.97; and 0.82, 0.72-0.94, respectively), and the treatment benefit was similar (interaction p = 0.615). Bariatric surgery was associated with reduced cardiovascular mortality in both subgroups (adjHR = 0.65, 95% CI: 0.46-0.91; and 0.70, 0.55-0.88, respectively (interaction p = 0.516)). CONCLUSIONS: Bariatric surgery is associated with similar reduction of overall and cardiovascular mortality and increased life expectancy regardless of baseline diabetes status.

Neither Gastric Bypass Surgery Nor Diet-Induced Weight-Loss Affect OATP1B1 Activity as Measured by Rosuvastatin Oral Clearance.

INTRODUCTION: Rosuvastatin pharmacokinetics is mainly dependent on the activity of hepatic uptake transporter OATP1B1. In this study, we aimed to investigate and disentangle the effect of Roux-en-Y gastric bypass (RYGB) and weight loss on oral clearance (CL/F) of rosuvastatin as a measure of OATP1B1-activity. METHODS: Patients with severe obesity preparing for RYGB (n = 40) or diet-induced weight loss (n = 40) were included and followed for 2 years, with four 24-hour pharmacokinetic investigations. Both groups underwent a 3-week low-energy diet (LED; < 1200 kcal/day), followed by RYGB or a 6-week very-low-energy diet (VLED; < 800 kcal/day). RESULTS: A total of 80 patients were included in the RYGB group (40 patients) and diet-group (40 patients). The weight loss was similar between the groups following LED and RYGB. The LED induced a similar (mean [95% CI]) decrease in CL/F in both intervention groups (RYGB: 16% [0, 31], diet: 23% [8, 38]), but neither induced VLED resulted in any further changes in CL/F. At Year 2, CL/F had increased by 21% from baseline in the RYGB group, while it was unaltered in the diet group. Patients expressing the reduced function SLCO1B1 variants (c.521TC/CC) showed similar changes in CL/F over time compared with patients expressing the wild-type variant. CONCLUSIONS: Neither body weight, weight loss nor RYGB per se seem to affect OATP1B1 activity to a clinically relevant degree. Overall, the observed changes in rosuvastatin pharmacokinetics were minor, and unlikely to be of clinical relevance.

Post-Authorization Safety Studies of Acute Liver Injury and Severe Complications of Urinary Tract Infection in Patients with Type 2 Diabetes Exposed to Dapagliflozin in a Real-World Setting.

INTRODUCTION: At the time of dapagliflozin's approval in Europe (2012) to treat patients with type 2 diabetes mellitus, concerns regarding acute liver injury and severe complications of urinary tract infection (sUTI) led to two post-authorization safety (PAS) studies of these outcomes to monitor the safety of dapagliflozin in real-world use. OBJECTIVE: To investigate the incidence of hospitalization for acute liver injury (hALI) or sUTI (pyelonephritis or urosepsis) among patients initiating dapagliflozin compared with other glucose-lowering drugs (GLDs). METHODS: These two noninterventional cohort studies identified initiators of dapagliflozin and comparator GLDs in November 2012-February 2019 using data from three longitudinal, population-based data sources: Clinical Practice Research Datalink (UK), the HealthCore Integrated Research Database (USA), and the Medicare database (USA). Outcomes (hALI and sUTI) were identified with electronic algorithms. Incidence rates were estimated by exposure group. Incidence rate ratios (IRRs) were calculated comparing dapagliflozin to comparator GLDs, using propensity score trimming and stratification to address confounding. The sUTI analyses were conducted separately by sex. RESULTS: In all data sources, hALI and sUTI incidence rates were generally lower in dapagliflozin initiators than comparator GLD initiators. The adjusted IRR (95% confidence interval) pooled across data sources for hALI was 0.85 (0.59-1.24) and for sUTI was 0.76 (0.60-0.96) in females and 0.74 (0.56-1.00) in males. Findings from sensitivity analyses were largely consistent with the primary analyses. CONCLUSIONS: These real-world studies do not suggest increased risks of hALI or sUTI, and they suggest a potential decreased risk of sUTI with dapagliflozin exposure compared with other GLDs.

Post-Authorization Safety Study of Hospitalization for Acute Kidney Injury in Patients with Type 2 Diabetes Exposed to Dapagliflozin in a Real-World Setting.

INTRODUCTION: Dapagliflozin is a sodium-glucose cotransporter 2 inhibitor approved to treat type 2 diabetes mellitus (T2DM), among other conditions. When dapagliflozin was approved in Europe for treating T2DM (2012), potential safety concerns regarding its effect on kidney function resulted in this post-authorization safety study to assess hospitalization for acute kidney injury (hAKI) among dapagliflozin initiators in a real-world setting. OBJECTIVE: The aim of this study was to evaluate the incidence of hAKI in adults with T2DM initiating dapagliflozin compared with other glucose-lowering drugs (GLDs). METHODS: This noninterventional cohort study identified new users of dapagliflozin and comparator GLDs from November 2012 to February 2019 from three longitudinal, population-based data sources: Clinical Practice Research Datalink (CPRD; United Kingdom), the HealthCore Integrated Research Database (HIRD; United States [US]), and Medicare (US). Electronic algorithms identified occurrences of hAKI, from which a sample underwent validation. Incidence rates for hAKI were calculated, and incidence rate ratios (IRRs) compared hAKI in dapagliflozin with comparator GLDs. Propensity score trimming and stratification were conducted for confounding adjustment. RESULTS: In all data sources, dapagliflozin initiators had a lower hAKI incidence rate than comparator GLD initiators (adjusted IRRs: CPRD, 0.44 [95% confidence interval (CI), 0.22-0.86]; HIRD, 0.76 [95% CI, 0.62-0.93]; Medicare, 0.69 [95% CI, 0.59-0.79]). The adjusted IRR pooled across the data sources was 0.70 (95% CI, 0.62-0.78). Results from sensitivity and stratified analyses were consistent with the primary analysis. CONCLUSIONS: This study, with > 34,000 person-years of real-world dapagliflozin exposure, suggests a decreased risk of hAKI in patients with T2DM exposed to dapagliflozin, aligning with results from dapagliflozin clinical trials. STUDY REGISTRATION: European Union Post-Authorisation Studies Register, EUPAS 11684; ClinicalTrials.gov, NCT02695082.

Dapagliflozin or Saxagliptin in Pediatric Type 2 Diabetes.

BACKGROUND: Incidence of type 2 diabetes (T2D) in children and adolescents is increasing, but treatment options are limited. METHODS: This was a 26-week, phase 3 trial with a 26-week extension among patients (10 to 17 years of age) with uncontrolled T2D (A1C 6.5 to 10.5%) receiving metformin, insulin, or both. Participants were randomly assigned 1:1:1 to 5 mg of dapagliflozin (N=81), 2.5 mg of saxagliptin (N=88), or placebo (N=76). Patients in active treatment groups with A1C ≥7% at week 12 were further randomly assigned 1:1 at week 14 to continue the dose or up-titrate to a higher dose (10 mg of dapagliflozin or 5 mg of saxagliptin). The primary end point was change in A1C at week 26. Safety was assessed over 52 weeks. RESULTS: At week 26, the difference versus placebo in adjusted mean change in A1C was −1.03 percentage points (95% confidence interval [CI], −1.57 to −0.49; P<0.001) for dapagliflozin and −0.44 percentage points (95% CI, −0.93 to 0.05; P=0.078) for saxagliptin. Adverse events (AEs) and serious AEs occurred in 72.8% and 8.6% of patients receiving dapagliflozin, 69.3% and 8.0% of patients receiving saxagliptin, and 71.1% and 6.6% of patients receiving placebo. Severe hypoglycemia occurred in 4.9%, 4.5%, and 7.9% of patients in each group, respectively. Over 52 weeks, the most common AE was headache (dapagliflozin 14.8%; placebo 5.3%). Most events were mild and none was considered serious or resulted in discontinuation. CONCLUSIONS: Dapagliflozin, but not saxagliptin, showed significant improvement in A1C compared with placebo. Nonserious headaches were more common in participants treated with dapagliflozin than in those receiving placebo. (Funded by AstraZeneca; ClinicalTrials.gov number, NCT03199053.)

Distance estimation in the goldfish (Carassius auratus).

Neurophysiological advances have given us exciting insights into the systems responsible for spatial mapping in mammals. However, we are still lacking information on the evolution of these systems and whether the underlying mechanisms identified are universal across phyla, or specific to the species studied. Here we address these questions by exploring whether a species that is evolutionarily distant from mammals can perform a task central to mammalian spatial mapping-distance estimation. We developed a behavioural paradigm allowing us to test whether goldfish (Carassius auratus) can estimate distance and explored the behavioural mechanisms that underpin this ability. Fish were trained to swim a set distance within a narrow tank covered with a striped pattern. After changing the background pattern, we found that goldfish use the spatial frequency of their visual environment to estimate distance, doubling the spatial frequency of the background pattern resulted in a large overestimation of the swimming distance. We present robust evidence that goldfish can accurately estimate distance and show that they use local optic flow to do so. These results provide a compelling basis to use goldfish as a model system to interrogate the evolution of the mechanisms that underpin spatial cognition, from brain to behaviour.

Visual odometry of Rhinecanthus aculeatus depends on the visual density of the environment.

Distance travelled is a crucial metric that underpins an animal's ability to navigate in the short-range. While there is extensive research on how terrestrial animals measure travel distance, it is unknown how animals navigating in aquatic environments estimate this metric. A common method used by land animals is to measure optic flow, where the speed of self-induced visual motion is integrated over the course of a journey. Whether freely-swimming aquatic animals also measure distance relative to a visual frame of reference is unclear. Using the marine fish Rhinecanthus aculeatus, we show that teleost fish can use visual motion information to estimate distance travelled. However, the underlying mechanism differs fundamentally from previously studied terrestrial animals. Humans and terrestrial invertebrates measure the total angular motion of visual features for odometry, a mechanism which does not vary with visual density. In contrast, the visual odometer used by Rhinecanthus acuelatus is strongly dependent on the visual density of the environment. Odometry in fish may therefore be mediated by a movement detection mechanism akin to the system underlying the optomotor response, a separate motion-detection mechanism used by both vertebrates and invertebrates for course and gaze stabilisation.

Impact of type 2 diabetes on in vivo activities and protein expressions of cytochrome P450 in patients with obesity.

Previous studies have not accounted for the close link between type 2 diabetes mellitus (T2DM) and obesity when investigating the impact of T2DM on cytochrome P450 (CYP) activities. The aim was to investigate the effect of T2DM on in vivo activities and protein expressions of CYP2C19, CYP3A, CYP1A2, and CYP2C9 in patients with obesity. A total of 99 patients from the COCKTAIL study (NCT02386917) were included in this cross-sectional analysis; 29 with T2DM and obesity (T2DM-obesity), 53 with obesity without T2DM (obesity), and 17 controls without T2DM and obesity (controls). CYP activities were assessed after the administration of a cocktail of probe drugs including omeprazole (CYP2C19), midazolam (CYP3A), caffeine (CYP1A2), and losartan (CYP2C9). Jejunal and liver biopsies were also obtained to determine protein concentrations of the respective CYPs. CYP2C19 activity and jejunal CYP2C19 concentration were 63% (-0.39 [95% CI: -0.82, -0.09]) and 40% (-0.09 fmol/µg protein [95% CI: -0.18, -0.003]) lower in T2DM-obesity compared with the obesity group, respectively. By contrast, there were no differences in the in vivo activities and protein concentrations of CYP3A, CYP1A2, and CYP2C9. Multivariable regression analyses also indicated that T2DM was associated with interindividual variability in CYP2C19 activity, but not CYP3A, CYP1A2, and CYP2C9 activities. The findings indicate that T2DM has a significant downregulating impact on CYP2C19 activity, but not on CYP3A, CYP1A2, and CYP2C9 activities and protein concentrations in patients with obesity. Hence, the effect of T2DM seems to be isoform-specific.

Correlations between 4ß-hydroxycholesterol and hepatic and intestinal CYP3A4: protein expression, microsomal ex vivo activity, and in vivo activity in patients with a wide body weight range.

PURPOSE: Variability in cytochrome P450 3A4 (CYP3A4) metabolism is mainly caused by non-genetic factors, hence providing a need for accurate phenotype biomarkers. Although 4ß-hydroxycholesterol (4ßOHC) is a promising endogenous CYP3A4 biomarker, additional investigations are required to evaluate its ability to predict CYP3A4 activity. This study investigated the correlations between 4ßOHC concentrations and hepatic and intestinal CYP3A4 protein expression and ex vivo microsomal activity in paired liver and jejunum samples, as well as in vivo CYP3A4 phenotyping (midazolam) in patients with a wide body weight range. METHODS: The patients (n = 96; 78 with obesity and 18 normal or overweight individuals) were included from the COCKTAIL-study (NCT02386917). Plasma samples for analysis of 4ßOHC and midazolam concentrations, and liver (n = 56) and jejunal (n = 38) biopsies were obtained. The biopsies for determination of CYP3A4 protein concentration and microsomal activity were obtained during gastric bypass or cholecystectomy. In vivo CYP3A4 phenotyping was performed using semi-simultaneous oral (1.5 mg) and intravenous (1.0 mg) midazolam. RESULTS: 4ßOHC concentrations were positively correlated with hepatic microsomal CYP3A4 activity (ρ = 0.53, p < 0.001), and hepatic CYP3A4 concentrations (ρ = 0.30, p = 0.027), but not with intestinal CYP3A4 concentrations (ρ = 0.18, p = 0.28) or intestinal microsomal CYP3A4 activity (ρ = 0.15, p = 0.53). 4ßOHC concentrations correlated weakly with midazolam absolute bioavailability (ρ = - 0.23, p = 0.027) and apparent oral clearance (ρ = 0.28, p = 0.008), but not with systemic clearance (ρ = - 0.03, p = 0.81). CONCLUSION: These findings suggest that 4ßOHC concentrations reflect hepatic, but not intestinal, CYP3A4 activity. Further studies should investigate the potential value of 4ßOHC as an endogenous biomarker for individual dose requirements of intravenously administered CYP3A4 substrate drugs. TRIAL REGISTRATION: Clinical. TRIALS: gov identifier: NCT02386917.

The Adaptive Renal Response for Volume Homeostasis During 2 Weeks of Dapagliflozin Treatment in People With Type 2 Diabetes and Preserved Renal Function on a Sodium-Controlled Diet.

Introduction: Proximal tubule sodium uptake is diminished following sodium glucose cotransporter 2 (SGLT2) inhibition. We previously showed that during SGLT2 inhibition, the kidneys adapt by increasing sodium uptake at distal tubular segments, thereby maintaining body sodium balance. Despite continuous glycosuria, we detected no increased urine volumes. We therefore assessed the adaptive renal responses to prevent excessive fluid loss. Methods: We conducted a mechanistic open-label study in people with type 2 diabetes mellitus with preserved kidney function, who received a standardized sodium intake (150 mmol/d) to evaluate the effects of dapagliflozin on renin-angiotensin-aldosterone system (RAAS) hormones, volume-related biomarkers, urinary albumin-to-creatinine ratio (UACR), and estimated glomerular filtration rate (eGFR), at start of treatment (day 4), end of treatment (day 14), and follow-up (day 18). Results: A total of 14 people were enrolled. Plasma renin and angiotensin II and urinary aldosterone and angiotensinogen were acutely and persistently increased during treatment with dapagliflozin. Plasma copeptin level was numerically increased after 4 days (21%). Similarly, fractional urea excretion was significantly decreased at start of treatment (-17%). Free water clearance was significantly decreased after 4 days (-74%) and 14 days (-41%). All changes reversed after dapagliflozin discontinuation. Conclusion: Dapagliflozin-induced osmotic diuresis triggers kidney adaptive mechanisms to maintain volume and sodium balance in people with type 2 diabetes and preserved kidney function. ClinicalTrials.gov (identification: NCT03152084).

Short- and long-term effects of body weight, calorie restriction and gastric bypass on CYP1A2, CYP2C19 and CYP2C9 activity.

AIM: Roux-en-Y gastric bypass (RYGB) may influence drug disposition due to surgery-induced gastrointestinal alterations and/or subsequent weight loss. The objective was to compare short- and long-term effects of RYGB and diet on the metabolic ratios of paraxanthine/caffeine (cytochrome P450 [CYP] 1A2 activity), 5-hydroxyomeprazole/omeprazole (CYP2C19 activity) and losartan/losartan carboxylic acid (CYP2C9 activity), and cross-sectionally compare these CYP-activities with normal-to-overweight controls. METHODS: This trial included patients with severe obesity preparing for RYGB (n = 40) or diet-induced (n = 41) weight loss, and controls (n = 18). Both weight loss groups underwent a 3-week low-energy diet (<1200 kcal/day, weeks 0-3) followed by a 6-week very-low-energy diet or RYGB (both <800 kcal/day, weeks 3-9). Follow-up time was 2 years, with four pharmacokinetic investigations. RESULTS: Mean ± SD weight loss from baseline was similar in the RYGB-group (13 ± 2.4%) and the diet group (10.5 ± 3.9%) at week 9, but differed at year 2 (RYGB -30 ± 6.9%, diet -3.1 ± 6.3%). From weeks 0 to 3, mean (95% confidence interval [CI]) CYP2C19 activity similarly increased in both groups (RYGB 43% [16, 55], diet 48% [22, 60]). Mean CYP2C19 activity increased by 30% (2.6, 43) after RYGB (weeks 3-9), but not in the diet-group (between-group difference -0.30 [-0.63, 0.03]). CYP2C19 activity remained elevated in the RYGB group at year 2. Baseline CYP2C19 activity was 2.7-fold higher in controls compared with patients with obesity, whereas no difference was observed in CYP1A2 and CYP2C9 activities. CONCLUSION: Our findings suggest that CYP2C19 activity is lower in patients with obesity and increases following weight loss. This may be clinically relevant for drug dosing. No clinically significant effect on CYP1A2 and CYP2C9 activities was observed.

Effects of dapagliflozin on volume status and systemic haemodynamics in patients with chronic kidney disease without diabetes: Results from DAPASALT and DIAMOND.

AIMS: To assess the effect of sodium-glucose cotransporter-2 inhibitor dapagliflozin on natriuresis, blood pressure (BP) and volume status in patients with chronic kidney disease (CKD) without diabetes. MATERIALS AND METHODS: We performed a mechanistic open-label study (DAPASALT) to evaluate the effects of dapagliflozin on 24-hour sodium excretion, 24-hour BP, extracellular volume, and markers of volume status during a standardized sodium diet (150 mmol/d) in six patients with CKD. In parallel, in a placebo-controlled double-blind crossover trial (DIAMOND), we determined the effects of 6 weeks of dapagliflozin on markers of volume status in 53 patients with CKD. RESULTS: In DAPASALT (mean age 65 years, mean estimated glomerular filtration rate [eGFR] 39.4 mL/min/1.73 m2 , median urine albumin:creatinine ratio [UACR] 111 mg/g), dapagliflozin did not change 24-hour sodium and volume excretion during 2 weeks of treatment. Dapagliflozin was associated with a modest increase in 24-hour glucose excretion on Day 4, which persisted at Day 14 and reversed to baseline after discontinuation. Mean 24-hour systolic BP decreased by -9.3 (95% confidence interval [CI] -19.1, 0.4) mmHg after 4 days and was sustained at Day 14 and at wash-out. Renin, angiotensin II, urinary aldosterone and copeptin levels increased from baseline. In DIAMOND (mean age 51 years, mean eGFR 59.0 mL/min/1.73 m2 , median UACR 608 mg/g), compared to placebo, dapagliflozin increased plasma renin (38.5 [95% CI 7.4, 78.8]%), aldosterone (19.1 [95% CI -5.9, 50.8]%), and copeptin levels (7.3 [95% CI 0.1, 14.5] pmol/L). CONCLUSIONS: During a standardized sodium diet, dapagliflozin decreased BP but did not increase 24-hour sodium and volume excretion. The lack of increased natriuresis and diuresis may be attributed to activation of intra-renal compensatory mechanisms to prevent excessive water loss.

Efficacy and safety of dapagliflozin in children and young adults with type 2 diabetes: a prospective, multicentre, randomised, parallel group, phase 3 study.

BACKGROUND: Since there are few treatment options for young people with type 2 diabetes, we aimed to assess the efficacy and safety of dapagliflozin as add-on therapy in children, adolescents, and young adults with type 2 diabetes receiving metformin, insulin, or both. METHODS: This multicentre, placebo-controlled, double-blind, randomised phase 3 study was undertaken at 30 centres in five countries (Hungary, Israel, Mexico, Russia, and the USA). Participants aged 10-24 years with type 2 diabetes and HbA1c concentration of 6·5-11% (48-97 mmol/mol) were randomly assigned 1:1 to oral dapagliflozin 10 mg or placebo during a 24 week double-blind period, which was then followed by a 28 week open-label safety extension in which all participants received dapagliflozin. Participants and study personnel were masked and participants were randomly assigned treatment (placebo or study drug) using an interactive web and voice response system. The primary outcome was between-group differences in change in HbA1c concentration from baseline to 24 weeks (intention-to-treat analysis). A prespecified sensitivity analysis of the primary outcome was also assessed in the per-protocol population, which included only protocol-compliant participants. This trial is registered with ClinicalTrials.gov, NCT02725593. FINDINGS: Between June 22, 2016, and March 15, 2019, 72 participants (19 [26%] of whom were aged 18-24 years) were randomly assigned (39 to dapagliflozin and 33 to placebo). Mean age was 16·1 (SD 3·3) years. In the intention-to-treat analysis, after 24 weeks, mean change in HbA1c concentration was -0·25% (95% CI -0·85 to 0·34; -2·7 [-9·3 to 3·7] mmol/mol) for dapagliflozin and 0·50% (-0·18 to 1·17; 5·5 [-2·0 to 12·8] mmol/mol) for placebo. The between-group difference was -0·75% (95% CI -1·65 to 0·15; -8·2 [-18·0 to 1·6] mmol/mol; p=0·10). In a sensitivity analysis in the per-protocol population (34 in the dapagliflozin group and 26 in the placebo group) after 24 weeks, mean change was -0·51% (-1·07 to 0·05; -5·6 [-11·7 to 0·5] mmol/mol) for dapagliflozin and 0·62% (-0·04 to 1·27; 6·8 [-0·4 to 13·9] mmol/mol) for placebo. The between-group difference was -1·13% (-1·99 to -0·26; -12·4 [-21·8 to -2·8] mmol/mol; p=0·012). Adverse events occurred in 27 (69%) dapagliflozin-assigned participants and 19 (58%) placebo-assigned participants over 24 weeks, and in 29 (74%) participants who received dapagliflozin over 52 weeks. Hypoglycaemia occurred in 11 (28%) dapagliflozin-assigned and six (18%) placebo-assigned participants who received dapagliflozin over 24 weeks and in 13 participants (33%) who received dapagliflozin over 52 weeks; none were considered as serious adverse events. No adverse events of diabetic ketoacidosis occurred. INTERPRETATION: The primary outcome of change in HbA1c concentration was not significant in the intention-to-treat analysis of children, adolescents, and young adults with type 2 diabetes receiving dapagliflozin in addition to standard-of-care treatment. A prespecified sensitivity analysis of protocol-compliant participants showed a significant difference in HbA1c concentration between groups. No new safety signals were identified and there was a low risk of severe hypoglycaemia. FUNDING: AstraZeneca.