GDF15 is dispensable for the insulin-sensitizing effects of chronic exercise.

Growth and differentiation factor 15 (GDF15) has recently emerged as a weight loss and insulin-sensitizing factor. Growing evidence also supports a role for GDF15 as a physiological, exercise-induced stress signal. Here, we tested whether GDF15 is required for the insulin-sensitizing effects of exercise in mice and humans. At baseline, both under a standard nutritional state and high-fat feeding, GDF15 knockout (KO) mice display normal glucose tolerance, systemic insulin sensitivity, maximal speed, and endurance running capacity when compared to wild-type littermates independent of sex. When submitted to a 4-week exercise training program, both lean and obese wild-type and GDF15 KO mice similarly improve their endurance running capacity, glucose tolerance, systemic insulin sensitivity, and peripheral glucose uptake. Insulin-sensitizing effects of exercise training were also unrelated to changes in plasma GDF15 in humans. In summary, we here show that GDF15 is dispensable for the insulin-sensitizing effects of chronic exercise.

Baseline phenotypes with preserved ß-cell function and high insulin concentrations have the best improvements in glucose tolerance after weight loss: results from the prospective DEXLIFE and EGIR-RISC studies.

BACKGROUND: Weight loss and lifestyle intervention improve glucose tolerance delaying the onset of type 2 diabetes (T2D), but individual responses are highly variable. Determining the predictive factors linked to the beneficial effects of weight loss on glucose tolerance could provide tools for individualized prevention plans. Thus, the aim was to investigate the relationship between pre-intervention values of insulin sensitivity and secretion and the improvement in glucose metabolism after weight loss. METHODS: In the DEXLIFE cohort (373 individuals at high risk of T2D, assigned 3:1 to a 12-week lifestyle intervention or a control arm, Trial Registration: ISRCTN66987085), K-means clustering and logistic regression analysis were performed based on pre-intervention indices of insulin sensitivity, insulin secretion (AUC-I), and glucose-stimulated insulin response (ratio of incremental areas of insulin and glucose, iAUC I/G). The response to the intervention was evaluated in terms of reduction of OGTT-glucose concentration. Clusters' validation was done in the prospective EGIR-RISC cohort (n = 1538). RESULTS: Four replicable clusters with different glycemic and metabolomic profiles were identified. Individuals had similar weight loss, but improvement in glycemic profile and ß-cell function was different among clusters, highly depending on pre-intervention insulin response to OGTT. Pre-intervention high insulin response was associated with the best improvement in AUC-G, while clusters with low AUC-I and iAUC I/G showed no beneficial effect of weight loss on glucose control, as also confirmed by the logistic regression model. CONCLUSIONS: Individuals with preserved ß-cell function and high insulin concentrations at baseline have the best improvement in glucose tolerance after weight loss.

Effect of Renal Impairment on the Pharmacokinetics of a Single Oral Dose of Danuglipron in Participants With Type 2 Diabetes.

Danuglipron (PF-06882961) is an oral, small-molecule glucagon-like peptide-1 receptor agonist in development for the treatment of type 2 diabetes (T2D) and obesity. Impaired renal function is prevalent in patients with T2D. This Phase 1, open-label study evaluated the effect of renal impairment on the pharmacokinetics, safety, and tolerability of danuglipron (20 mg) in healthy participants with normal renal function (estimated glomerular filtration rate [eGFR] unnormalized for body surface area: ≥90 mL/min), in participants with T2D and normal renal function (eGFR ≥90 mL/min), and in participants with T2D and mild (eGFR 60-89 mL/min), moderate (eGFR 30-59 mL/min), or severe (eGFR <30 mL/min) renal impairment (N = 39). Log-linear regression analyses and analyses of variance showed no evidence of a clinically significant effect of reduced renal function on danuglipron pharmacokinetics. Renal clearance of unchanged danuglipron was minimal (<1% across all renal function groups). Danuglipron pharmacokinetics were similar between healthy participants and participants with T2D and normal renal function. A single 20-mg oral dose of danuglipron was generally safe and well tolerated in all participant groups. In participants with T2D, renal impairment had no clinically meaningful effect on the pharmacokinetic, safety, and tolerability profiles of danuglipron, indicating that dose adjustment of danuglipron will not be required when administered to patients with T2D and reduced renal function.

The impact of 60 days of -6° head down tilt bed rest on mitochondrial content, respiration and regulators of mitochondrial dynamics.

It is unclear how skeletal muscle metabolism and mitochondrial function adapt to long duration bed rest and whether changes can be prevented by nutritional intervention. The present study aimed (1) to assess the effect of prolonged bed rest on skeletal muscle mitochondrial function and dynamics and (2) to determine whether micronutrient supplementation would mitigate the adverse metabolic effect of bed rest. Participants were maintained in energy balance throughout 60 days of bed rest with micronutrient supplementation (INT) (body mass index: 23.747 ± 1.877 kg m-2 ; 34.80 ± 7.451 years; n = 10) or without (control) (body mass index: 24.087 ± 2.088 kg m-2 ; 33.50 ± 8.541 years; n = 10). Indirect calorimetry and dual-energy x-ray absorptiometry were used for measures of energy expenditure, exercise capacity and body composition. Mitochondrial respiration was determined by high-resolution respirometry in permeabilized muscle fibre bundles from vastus lateralis biopsies. Protein and mRNA analysis further examined the metabolic changes relating to regulators of mitochondrial dynamics induced by bed rest. INT was not sufficient in preserving whole body metabolic changes conducive of a decrease in body mass, fat-free mass and exercise capacity within both groups. Mitochondrial respiration, OPA1 and Drp1 protein expression decreased with bed rest, with an increase pDrp1s616 . This reduction in mitochondrial respiration was explained through an observed decrease in mitochondrial content (mtDNA:nDNA). Changes in regulators of mitochondrial dynamics indicate an increase in mitochondrial fission driven by a decrease in inner mitochondrial membrane fusion (OPA1) and increased pDrp1s616 . KEY POINTS: Sixty days of -6° head down tilt bed rest leads to significant changes in body composition, exercise capacity and whole-body substrate metabolism. Micronutrient supplementation throughout bed rest did not preserve whole body metabolic changes. Bed rest results in a decrease in skeletal muscle mitochondrial respiratory capacity, mainly as a result of an observed decrease in mitochondrial content. Prolonged bed rest ensues changes in key regulators of mitochondrial dynamics. OPA1 and Drp1 are significantly reduced, with an increase in pDrp1s616 following bed rest indicative of an increase in mitochondrial fission. Given the reduction in mitochondrial content following 60 days of bed rest, the maintenance of regulators of mitophagy in line with the increase in regulators of mitochondrial fission may act to maintain mitochondrial respiration to meet energy demands.

SIRT4 is a regulator of human skeletal muscle fatty acid metabolism influencing inner and outer mitochondrial membrane-mediated fusion.

OBJECTIVE: The mitochondrial phenotype, governed by the balance of fusion-fission, is a key determinant of energy metabolism. The inner and outer mitochondrial membrane (IMM) fusion proteins optic atrophy 1 (OPA1) and Mitofusin 1 and 2 (Mfn1/2) play an important role in this process. Recent evidence also shows that Sirtuin 4 (SIRT4), located within the mitochondria, is involved in the regulation of fatty acid oxidation. The purpose of this study was to determine if SIRT4 expression regulates inner and outer mitochondrial-mediated fusion and substrate utilization within differentiated human skeletal muscle cells (HSkMC). MATERIAL AND METHODS: SIRT4 expression was knocked down using small interfering RNA (siRNA) transfection in differentiated HSkMC. Following knockdown, mitochondrial respiration was determined by high-resolution respirometry (HRR) using the Oroboros Oxygraph O2k. Live cell confocal microscopy, quantified using the Mitochondrial Network Analysis (MiNA) toolset, was used to examine mitochondrial morphological change. This was further examined through the measurement of key metabolic and mitochondrial morphological regulators (mRNA and protein) induced by knockdown. RESULTS: SIRT4 knockdown resulted in a significant decrease in LEAK respiration, potentially explained by a decrease in ANT1 protein expression. Knockdown further increased oxidative phosphorylation and protein expression of key regulators of fatty acid metabolism. Quantitative analysis of live confocal imaging of fluorescently labelled mitochondria following SIRT4 knockdown supported the role SIRT4 plays in the regulation of mitochondrial morphology, as emphasized by an increase in mitochondrial network branches and junctions. Measurement of key regulators of mitochondrial dynamics illustrated a significant increase in mitochondrial fusion proteins Mfn1, OPA1 respectively, indicative of an increase in mitochondrial size. CONCLUSIONS: This study provides evidence of a direct relationship between the mitochondrial phenotype and substrate oxidation in HSkMC. We identify SIRT4 as a key protagonist of energy metabolism via its regulation of IMM and OMM fusion proteins, OPA1 and Mfn1. SIRT4 knockdown increases mitochondrial capacity to oxidize fatty acids, decreasing LEAK respiration and further increasing mitochondrial elongation via its regulation of mitochondrial fusion.

Tolerability, safety and pharmacodynamics of oral, small-molecule glucagon-like peptide-1 receptor agonist danuglipron for type 2 diabetes: A 12-week, randomized, placebo-controlled, Phase 2 study comparing different dose-escalation schemes.

AIM: To evaluate the tolerability, safety and pharmacodynamics of different dose-escalation schemes of the oral small-molecule glucagon-like peptide-1 receptor (GLP-1R) agonist danuglipron. MATERIALS AND METHODS: This Phase 2a, double-blind, placebo-controlled, parallel-group study randomly assigned adults with type 2 diabetes (T2D) treated with metformin to placebo or danuglipron (low [5-mg] or high [10-mg] starting dose, with 1- or 2-week dose-escalation steps, to target doses of 80, 120 or 200 mg twice daily [BID]) and adults with obesity without diabetes to placebo or danuglipron 200 mg BID. RESULTS: Participants with T2D (n = 123, mean glycated haemoglobin [HbA1c] 8.19%) or obesity without diabetes (n = 28, mean body mass index 37.3 kg/m2 ) were randomly assigned and treated. Discontinuation from study medication occurred in 27.3% to 72.7% of participants across danuglipron groups versus 16.7% to 18.8% for placebo, most often due to adverse events. Nausea (20.0%-47.6% of participants across danuglipron groups vs. 12.5% for placebo) and vomiting (18.2%-40.9% danuglipron vs. 12.5% placebo, respectively) were most commonly reported in participants with T2D. Gastrointestinal adverse events were generally related to danuglipron target dose and were not substantially affected by starting dose. In participants with T2D, least squares mean changes from baseline in HbA1c (-1.04% to -1.57% across danuglipron groups vs. -0.32% for placebo), fasting plasma glucose (-23.34 mg/dL to -53.94 mg/dL danuglipron vs. -13.09 mg/dL placebo) and body weight (-1.93 to -5.38 kg danuglipron vs. -0.42 kg placebo) at Week 12 were generally statistically significant for danuglipron compared with placebo (P < 0.05). CONCLUSIONS: Danuglipron resulted in statistically significant reductions in HbA1c, FPG and body weight over 12 weeks, in the setting of higher discontinuation rates and incidence of gastrointestinal adverse events with higher target doses. CLINICALTRIALS: gov identifier: NCT04617275.

Efficacy and Safety of Oral Small Molecule Glucagon-Like Peptide 1 Receptor Agonist Danuglipron for Glycemic Control Among Patients With Type 2 Diabetes: A Randomized Clinical Trial.

Importance: Currently available glucagon-like peptide 1 receptor (GLP-1R) agonists for treating type 2 diabetes (T2D) are peptide agonists that require subcutaneous administration or strict fasting requirements before and after oral administration. Objective: To investigate the efficacy, safety, and tolerability of multiple dose levels of the novel, oral, small molecule GLP-1R agonist danuglipron over 16 weeks. Design, Setting, and Participants: A phase 2b, double-blind, placebo-controlled, parallel-group, 6-group randomized clinical trial with 16-week double-blind treatment period and 4-week follow-up was conducted from July 7, 2020, to July 7, 2021. Adults with T2D inadequately controlled by diet and exercise, with or without metformin treatment, were enrolled from 97 clinical research sites in 8 countries or regions. Interventions: Participants received placebo or danuglipron, 2.5, 10, 40, 80, or 120 mg, all orally administered twice daily with food for 16 weeks. Weekly dose escalation steps were incorporated to achieve danuglipron doses of 40 mg or more twice daily. Main Outcomes and Measures: Change from baseline in glycated hemoglobin (HbA1c, primary end point), fasting plasma glucose (FPG), and body weight were assessed at week 16. Safety was monitored throughout the study period, including a 4-week follow-up period. Results: Of 411 participants randomized and treated (mean [SD] age, 58.6 [9.3] years; 209 [51%] male), 316 (77%) completed treatment. For all danuglipron doses, HbA1c and FPG were statistically significantly reduced at week 16 vs placebo, with HbA1c reductions up to a least squares mean difference vs placebo of -1.16% (90% CI, -1.47% to -0.86%) for the 120-mg twice daily group and FPG reductions up to a least squares mean difference vs placebo of -33.24 mg/dL (90% CI, -45.63 to -20.84 mg/dL). Body weight was statistically significantly reduced at week 16 compared with placebo in the 80-mg twice daily and 120-mg twice daily groups only, with a least squares mean difference vs placebo of -2.04 kg (90% CI, -3.01 to -1.07 kg) for the 80-mg twice daily group and -4.17 kg (90% CI, -5.15 to -3.18 kg) for the 120-mg twice daily group. The most commonly reported adverse events were nausea, diarrhea, and vomiting. Conclusions and Relevance: In adults with T2D, danuglipron reduced HbA1c, FPG, and body weight at week 16 compared with placebo, with a tolerability profile consistent with the mechanism of action. Trial Registration: ClinicalTrials.gov Identifier: NCT03985293.

Decreased expression of mitochondrial aminoacyl-tRNA synthetases causes downregulation of OXPHOS subunits in type 2 diabetic muscle.

Type 2 diabetes mellitus (T2D) affects millions of people worldwide and is one of the leading causes of morbidity and mortality. The skeletal muscle (SKM) is one of the most important tissues involved in maintaining glucose homeostasis and substrate oxidation, and it undergoes insulin resistance in T2D. In this study, we identify the existence of alterations in the expression of mitochondrial aminoacyl-tRNA synthetases (mt-aaRSs) in skeletal muscle from two different forms of T2D: early-onset type 2 diabetes (YT2) (onset of the disease before 30 years of age) and the classical form of the disease (OT2). GSEA analysis from microarray studies revealed the repression of mitochondrial mt-aaRSs independently of age, which was validated by real-time PCR assays. In agreement with this, a reduced expression of several encoding mt-aaRSs was also detected in skeletal muscle from diabetic (db/db) mice but not in obese ob/ob mice. In addition, the expression of the mt-aaRSs proteins most relevant in the synthesis of mitochondrial proteins, threonyl-tRNA, and leucyl-tRNA synthetases (TARS2 and LARS2) were also repressed in muscle from db/db mice. It is likely that these alterations participate in the reduced expression of proteins synthesized in the mitochondria detected in db/db mice. We also document an increased iNOS abundance in mitochondrial-enriched muscle fractions from diabetic mice that may inhibit aminoacylation of TARS2 and LARS2 by nitrosative stress. Our results indicate a reduced expression of mt-aaRSs in skeletal muscle from T2D patients, which may participate in the reduced expression of proteins synthesized in mitochondria. An enhanced mitochondrial iNOS could play a regulatory role in diabetes.

Adipose tissue is a source of regenerative cells that augment the repair of skeletal muscle after injury.

Fibro-adipogenic progenitors (FAPs) play a crucial role in skeletal muscle regeneration, as they generate a favorable niche that allows satellite cells to perform efficient muscle regeneration. After muscle injury, FAP content increases rapidly within the injured muscle, the origin of which has been attributed to their proliferation within the muscle itself. However, recent single-cell RNAseq approaches have revealed phenotype and functional heterogeneity in FAPs, raising the question of how this differentiation of regenerative subtypes occurs. Here we report that FAP-like cells residing in subcutaneous adipose tissue (ScAT), the adipose stromal cells (ASCs), are rapidly released from ScAT in response to muscle injury. Additionally, we find that released ASCs infiltrate the damaged muscle, via a platelet-dependent mechanism and thus contribute to the FAP heterogeneity. Moreover, we show that either blocking ASCs infiltration or removing ASCs tissue source impair muscle regeneration. Collectively, our data reveal that ScAT is an unsuspected physiological reservoir of regenerative cells that support skeletal muscle regeneration, underlining a beneficial relationship between muscle and fat.

A phase 1 study to evaluate the safety, tolerability, pharmacokinetics and pharmacodynamics of danuglipron (PF-06882961), an oral small-molecule glucagon-like peptide-1 receptor agonist, in Japanese adults with type 2 diabetes mellitus.

AIMS: This study investigated the safety, tolerability, pharmacokinetics and pharmacodynamics of danuglipron (PF-06882961), which is a novel, oral small-molecule glucagon-like peptide-1 receptor agonist, in Japanese participants with type 2 diabetes mellitus (T2DM). MATERIALS AND METHODS: This phase 1, randomized, double-blind, placebo-controlled, parallel-group study enrolled adult Japanese participants with T2DM inadequately controlled on diet and exercise. Participants received twice-daily oral doses of placebo or multiple ascending doses of danuglipron titrated to 40, 80 or 120 mg twice daily over 8 weeks. The primary outcome was the safety and tolerability of danuglipron. Secondary and exploratory outcomes included plasma pharmacokinetics, glycaemic parameters and body weight. RESULTS: In the 37 participants randomized, the most common treatment-emergent adverse events were nausea, vomiting, abdominal discomfort, diarrhoea and headache. Most treatment-emergent adverse events were of mild or moderate intensity. Dose-proportional increases in danuglipron exposure parameters were observed at steady state (Day 56). Significant reductions from baseline were observed with danuglipron on Day 56 for mean daily glucose [least squares mean (90% confidence interval) placebo-adjusted difference of up to -67.89 (-88.98, -46.79) mg/dl] and on Day 57 for fasting plasma glucose [up to -40.87 (-53.77, -27.98) mg/dl], glycated haemoglobin [up to -1.41% (-2.01%, -0.82%)] and body weight [up to -1.87 (-3.58, -0.17) kg]. CONCLUSIONS: In Japanese adults with T2DM, danuglipron exhibited dose-proportional increases in plasma exposure at steady state and robustly reduced glycaemic parameters and body weight after 8 weeks of dosing, with a safety profile consistent with the mechanism of action.

OPA1 regulation of mitochondrial dynamics in skeletal and cardiac muscle.

The mitochondria are double-membrane organelles integral for energy metabolism. Mitochondrial dynamics is regulated by inner and outer mitochondrial membrane (IMM and OMM) proteins, which promote fission and fusion. Optic atrophy 1 (OPA1) regulates IMM fusion, prevents apoptosis, and is a key regulator of morphological change in skeletal and cardiac muscle physiology and pathophysiology. OPA1 fuses the inner membranes of adjacent mitochondria, allowing for an increase in oxidative phosphorylation (OXPHOS). Considering the importance of energy metabolism in whole-body physiology, OPA1 and its regulators have been proposed as novel targets for the treatment of skeletal muscle atrophy and heart failure. Here, we review the role and regulation of OPA1 in skeletal muscle and cardiac pathophysiology, epitomizing its critical role in the cell.

Associations between exploratory dietary patterns and incident type 2 diabetes: a federated meta-analysis of individual participant data from 25 cohort studies.

PURPOSE: In several studies, exploratory dietary patterns (DP), derived by principal component analysis, were inversely or positively associated with incident type 2 diabetes (T2D). However, findings remained study-specific, inconsistent and rarely replicated. This study aimed to investigate the associations between DPs and T2D in multiple cohorts across the world. METHODS: This federated meta-analysis of individual participant data was based on 25 prospective cohort studies from 5 continents including a total of 390,664 participants with a follow-up for T2D (3.8-25.0 years). After data harmonization across cohorts we evaluated 15 previously identified T2D-related DPs for association with incident T2D estimating pooled incidence rate ratios (IRR) and confidence intervals (CI) by Piecewise Poisson regression and random-effects meta-analysis. RESULTS: 29,386 participants developed T2D during follow-up. Five DPs, characterized by higher intake of red meat, processed meat, French fries and refined grains, were associated with higher incidence of T2D. The strongest association was observed for a DP comprising these food groups besides others (IRRpooled per 1 SD = 1.104, 95% CI 1.059-1.151). Although heterogeneity was present (I2 = 85%), IRR exceeded 1 in 18 of the 20 meta-analyzed studies. Original DPs associated with lower T2D risk were not confirmed. Instead, a healthy DP (HDP1) was associated with higher T2D risk (IRRpooled per 1 SD = 1.057, 95% CI 1.027-1.088). CONCLUSION: Our findings from various cohorts revealed positive associations for several DPs, characterized by higher intake of red meat, processed meat, French fries and refined grains, adding to the evidence-base that links DPs to higher T2D risk. However, no inverse DP-T2D associations were confirmed.

Yeast Mannan-Rich Fraction Modulates Endogenous Reactive Oxygen Species Generation and Antibiotic Sensitivity in Resistant E. coli.

Mannan-rich fraction (MRF) isolated from Saccharomyces cerevisiae has been studied for its beneficial impact on animal intestinal health. Herein, we examined how MRF affected the formation of reactive oxygen species (ROS), impacting antibiotic susceptibility in resistant Escherichia coli through the modulation of bacterial metabolism. The role of MRF in effecting proteomic change was examined using a proteomics-based approach. The results showed that MRF, when combined with bactericidal antibiotic treatment, increased ROS production in resistant E. coli by 59.29 ± 4.03% compared to the control (p ≤ 0.05). We further examined the effect of MRF alone and in combination with antibiotic treatment on E. coli growth and explored how MRF potentiates bacterial susceptibility to antibiotics via proteomic changes in key metabolic pathways. Herein we demonstrated that MRF supplementation in the growth media of ampicillin-resistant E. coli had a significant impact on the normal translational control of the central metabolic pathways, including those involved in the glycolysis-TCA cycle (p ≤ 0.05).

Endurance exercise training-responsive miR-19b-3p improves skeletal muscle glucose metabolism.

Skeletal muscle is a highly adaptable tissue and remodels in response to exercise training. Using short RNA sequencing, we determine the miRNA profile of skeletal muscle from healthy male volunteers before and after a 14-day aerobic exercise training regime. Among the exercise training-responsive miRNAs identified, miR-19b-3p was selected for further validation. Overexpression of miR-19b-3p in human skeletal muscle cells increases insulin signaling, glucose uptake, and maximal oxygen consumption, recapitulating the adaptive response to aerobic exercise training. Overexpression of miR-19b-3p in mouse flexor digitorum brevis muscle enhances contraction-induced glucose uptake, indicating that miR-19b-3p exerts control on exercise training-induced adaptations in skeletal muscle. Potential targets of miR-19b-3p that are reduced after aerobic exercise training include KIF13A, MAPK6, RNF11, and VPS37A. Amongst these, RNF11 silencing potentiates glucose uptake in human skeletal muscle cells. Collectively, we identify miR-19b-3p as an aerobic exercise training-induced miRNA that regulates skeletal muscle glucose metabolism.

A Phase 1 first-in-human study of the safety, tolerability, and pharmacokinetics of the ROBO2 fusion protein PF-06730512 in healthy participants.

Proteinuria associated with podocyte effacement is a hallmark of focal segmental glomerulosclerosis (FSGS). Preclinical studies implicated ROBO2/SLIT2 signaling in the regulation of podocyte adhesion, and inhibition of this pathway is a novel target to slow FSGS disease progression. This first-in-human dose-escalation study evaluated the safety, tolerability, pharmacokinetics, and immunogenicity of PF-06730512, an Fc fusion protein that targets the ROBO2/SLIT2 pathway, in healthy adults. In this Phase 1, double-blind, sponsor-open study, single ascending dose (SAD) cohorts were randomized to receive up to 1000 mg or placebo intravenously (IV); multiple ascending dose (MAD) cohorts were randomized to receive up to 400 mg subcutaneous (SC) doses, 1000 mg IV dose, or matching placebo. Safety evaluations were performed up to 71 (SAD) and 113 (MAD) days after dosing; blood samples were collected to measure serum PF-06730512 concentrations and antidrug antibodies (ADA) to PF-06730512. Seventy-nine participants (SAD, 47; MAD, 32) were enrolled. There were 108 mild (SAD, 46; MAD, 62) and 21 moderate (SAD, 13; MAD, 8) treatment-emergent adverse events (TEAEs); no deaths, treatment-related serious AEs, severe TEAEs, or infusion reactions were reported. PF-06730512 exposure generally increased in an approximately dose-proportional manner; mean t1/2 ranged from 12-15 days across 50-1000 mg doses. Immunogenicity incidence was low (SAD, 0 ADA+; MAD, 2 ADA+). In conclusion, single IV doses of PF-06730512 up to 1000 mg and multiple IV and SC dosing up to 1000 and 400 mg, respectively, were safe and well tolerated in healthy participants. Further trials in patients with FSGS are warranted. Clinical trial registration: Clinicaltrials.gov: NCT03146065.

PODO: Trial Design: Phase 2 Study of PF-06730512 in Focal Segmental Glomerulosclerosis.

INTRODUCTION: Focal segmental glomerulosclerosis (FSGS) is characterized by proteinuria and a histologic pattern of glomerular lesions of diverse etiology that share features including glomerular scarring and podocyte foot process effacement. Roundabout guidance receptor 2 (ROBO2)/slit guidance ligand 2 (SLIT2) signaling destabilizes the slit diaphragm and reduces podocyte adhesion to the glomerular basement membrane (GBM). Preclinical studies suggest that inhibition of glomerular ROBO2/SLIT2 signaling can stabilize podocyte adhesion and reduce proteinuria. This clinical trial evaluates the preliminary efficacy and safety of ROBO2/SLIT2 inhibition with the ROBO2 fusion protein PF-06730512 in patients with FSGS. METHODS: The Study to Evaluate PF-06730512 in Adults With FSGS (PODO; ClinicalTrials.gov identifier NCT03448692), an open-label, phase 2a, multicenter trial in adults with FSGS, will enroll patients into 2 cohorts (n = 22 per cohort) to receive either high- or low-dose PF-06730512 (intravenous) every 2 weeks for 12 weeks. Key inclusion criteria include a confirmed biopsy diagnosis of FSGS, an estimated glomerular filtration rate (eGFR) ≥45 ml/min/1.73 m2 based on the Chronic Kidney Disease Epidemiology Collaboration formula (30-45 with a recent biopsy), and urinary protein-to-creatinine ratio (UPCR) >1.5 g/g. Key exclusion criteria include collapsing FSGS, serious/active infection, ≥50% tubulointerstitial fibrosis on biopsy, and organ transplantation. The primary endpoint is change from baseline to week 13 in UPCR; secondary endpoints include safety, changes in eGFR, and PF-06730512 serum concentration. RESULTS: This ongoing trial will report the efficacy, safety, pharmacokinetics, and biomarker results of PF-06730512 for patients with FSGS. CONCLUSION: Findings from this proof-of-concept study may support further development and evaluation of PF-06730512 to treat FSGS and warrant assessment in phase 3 clinical trials.

Danuglipron (PF-06882961) in type 2 diabetes: a randomized, placebo-controlled, multiple ascending-dose phase 1 trial.

Agonism of the glucagon-like peptide-1 receptor (GLP-1R) results in glycemic lowering and body weight loss and is a therapeutic strategy to treat type 2 diabetes (T2D) and obesity. We developed danuglipron (PF-06882961), an oral small-molecule GLP-1R agonist and found it had comparable efficacy to injectable peptidic GLP-1R agonists in a humanized mouse model. We then completed a placebo-controlled, randomized, double-blind, multiple ascending-dose phase 1 study ( NCT03538743 ), in which we enrolled 98 patients with T2D on background metformin and randomized them to receive multiple ascending doses of danuglipron or placebo for 28 d, across eight cohorts. The primary outcomes were assessment of adverse events (AEs), safety laboratory tests, vital signs and 12-lead electrocardiograms. Most AEs were mild, with nausea, dyspepsia and vomiting most commonly reported. There were no clinically meaningful AEs in laboratory values across groups. Heart rate generally increased with danuglipron treatment at day 28, but no heart-rate AEs were reported. Systolic blood pressure was slightly decreased and changes in diastolic blood pressure were similar with danuglipron treatment at day 28, compared with placebo. There were no clinically meaningful electrocardiogram findings. In this study in T2D, danuglipron was generally well tolerated, with a safety profile consistent with the mechanism of action of GLP-1R agonism.

Growth hormone replacement may influence the biological action of thyroid hormone on liver and bone tissue.

OBJECTIVE: Growth hormone (GH) replacement alters the peripheral interconversion of thyroxine (T4) and triiodothyronine (T3). However, little is known about the clinical impact of these alterations. We aimed to compare changes observed in the serum T3:T4 ratio with known biological markers of thyroid hormone action derived from different peripheral tissues. DESIGN: We prospectively studied twenty GH deficient men before and after GH replacement in a tertiary referral endocrine center. Serum biochemical measurements included insulin like growth factor-1 (IGF-1), thyroid hormones (free & total T3, free & total T4 and reverse T3) and TSH. Changes in thyroid hormone concentration were compared to alterations in hepatic and bone biomarkers of thyroid hormone action. RESULTS: GH replacement provoked a decline in serum free T4 concentration (-1.09 ± 1.99 pmol/L; p = 0.02) and an increase in free T3 (+0.34 ± 0.15 pmol/L; p = 0.03); therefore, the free T3:free T4 ratio increased from 0.40 ± 0.02 to 0.47 ± 0.02 (p = 0.002). Sex hormone binding globulin (SHBG) level was unchanged. However, a decline in serum ferritin (-26.6 ± 8.5 ng/mL; p = 0.005) correlated with a fall in freeT4. Alterations in lipid profile, including a rise in large HDL sub-fractions and Lp (a) (+2.1 ± 21.1 nmol/L; p = 0.002) did not correlate with thyroid hormone levels. Significant increases were recorded in serum bone turnover markers - procollagen type 1 amino-terminal propeptide +57.4%; p = 0.0009, osteocalcin +48.6%; p = 0.0007; c-terminal telopeptides of type 1 collagen +73.7%; p = 0.002. Changes in bone formation markers occurred in parallel with fluctuations in thyroid hormone. CONCLUSION: GH-induced alterations in the thyroid axis are associated with complex, tissue specific effects on thyroid hormone action. Modulation of bone turnover markers suggests that GH may improve the biological action of thyroid hormone on bone.

Heterogeneity of Associations between Total and Types of Fish Intake and the Incidence of Type 2 Diabetes: Federated Meta-Analysis of 28 Prospective Studies Including 956,122 Participants.

The association between fish consumption and new-onset type 2 diabetes is inconsistent and differs according to geographical location. We examined the association between the total and types of fish consumption and type 2 diabetes using individual participant data from 28 prospective cohort studies from the Americas (6), Europe (15), the Western Pacific (6), and the Eastern Mediterranean (1) comprising 956,122 participants and 48,084 cases of incident type 2 diabetes. Incidence rate ratios (IRRs) for associations of total fish, shellfish, fatty, lean, fried, freshwater, and saltwater fish intake and type 2 diabetes were derived for each study, adjusting for a consistent set of confounders and combined across studies using random-effects meta-analysis. We stratified all analyses by sex due to observed interaction (p = 0.002) on the association between fish and type 2 diabetes. In women, for each 100 g/week higher intake the IRRs (95% CIs) of type 2 diabetes were 1.02 (1.01-1.03, I2 = 61%) for total fish, 1.04 (1.01-1.07, I2 = 46%) for fatty fish, and 1.02 (1.00-1.04, I2 = 33%) for lean fish. In men, all associations were null. In women, we observed variation by geographical location: IRRs for total fish were 1.03 (1.02-1.04, I2 = 0%) in the Americas and null in other regions. In conclusion, we found evidence of a neutral association between total fish intake and type 2 diabetes in men, but there was a modest positive association among women with heterogeneity across studies, which was partly explained by geographical location and types of fish intake. Future research should investigate the role of cooking methods, accompanying foods and environmental pollutants, but meanwhile, existing dietary regional, national, or international guidelines should continue to guide fish consumption within overall healthy dietary patterns.

Associations of Total Legume, Pulse, and Soy Consumption with Incident Type 2 Diabetes: Federated Meta-Analysis of 27 Studies from Diverse World Regions.

BACKGROUND: The consumption of legumes is promoted as part of a healthy diet in many countries but associations of total and types of legume consumption with type 2 diabetes (T2D) are not well established. Analyses across diverse populations are lacking despite the availability of unpublished legume consumption data in prospective cohort studies. OBJECTIVE: To examine the prospective associations of total and types of legume intake with the risk of incident T2D. METHODS: Meta-analyses of associations between total legume, pulse, and soy consumption and T2D were conducted using a federated approach without physical data-pooling. Prospective cohorts were included if legume exposure and T2D outcome data were available and the cohort investigators agreed to participate. We estimated incidence rate ratios (IRRs) and CIs of associations using individual participant data including ≤42,473 incident cases among 807,785 adults without diabetes in 27 cohorts across the Americas, Eastern Mediterranean, Europe, and Western Pacific. Random-effects meta-analysis was used to combine effect estimates and estimate heterogeneity. RESULTS: Median total legume intake ranged from 0-140 g/d across cohorts. We observed a weak positive association between total legume consumption and T2D (IRR = 1.02, 95% CI: 1.01 to 1.04) per 20 g/d higher intake, with moderately high heterogeneity (I2 = 74%). Analysis by region showed no evidence of associations in the Americas, Eastern Mediterranean, and Western Pacific. The positive association in Europe (IRR = 1.05, 95% CI: 1.01 to 1.10, I2 = 82%) was mainly driven by studies from Germany, UK, and Sweden. No evidence of associations was observed for the consumption of pulses or soy. CONCLUSIONS: These findings suggest no evidence of an association of legume intakes with T2D in several world regions. The positive association observed in some European studies warrants further investigation relating to overall dietary contexts in which legumes are consumed, including accompanying foods which may be positively associated with T2D.