Mindfulness-based intervention for depression and insulin resistance in adolescents: Protocol for BREATHE, a multisite, pilot and feasibility randomized controlled trial

BACKGROUND

Elevated depression symptoms have been associated with higher insulin resistance in adolescents, and consequently, greater risk for type 2 diabetes (T2D). Mindfulness-based intervention (MBI) may be suited for adolescents at risk for T2D given its potential to decrease depression and improve stress-related behavior/physiology underpinning insulin resistance. To prepare for a future multisite efficacy randomized controlled trial, a rigorous, multisite, pilot and feasibility study is needed to test this approach. The current paper describes the design and protocol for a multisite, pilot and feasibility randomized controlled trial of six-week MBI, cognitive-behavioral therapy (CBT), and health education (HealthEd) group interventions, to assess multisite fidelity, feasibility, and acceptability.

METHODS

Participants are N = 120 adolescents ages 12-17, with body mass index (BMI) ≥85th percentile, elevated depression symptoms (20-item Center for Epidemiologic Studies-Depression Scale total score > 20), and family history of diabetes. Enrollment occurs across four United States (US) sites, two in Colorado, one in Washington, D·C., and one in Maryland. Group interventions are delivered virtually by trained psychologists and co-facilitators. Assessments occur at baseline, six-week follow-up, and one-year follow-up.

RESULTS

Primary outcomes are intervention implementation fidelity, based upon expert ratings of audio-recorded sessions (≥80% adherence/competence), and recruitment feasibility, based upon percentage enrollment of eligible youth (≥80%). Secondary outcomes are intervention training fidelity/feasibility/acceptability, recruitment timeframe, and retention/assessment feasibility.

CONCLUSION

Findings will inform optimization of training, recruitment, intervention delivery, retention, and assessment protocols for a multisite, efficacy randomized controlled trial evaluating MBI for decreasing depression and improving insulin resistance in adolescents at risk for developing T2D.

Reevaluating First-line Therapies in Youth-Onset Type 2 Diabetes

The prevalence of youth-onset type 2 diabetes is growing worldwide and current first-line treatment with metformin and intensive behavior and lifestyle changes are suboptimal in over 50% of youth within 2 years of diagnosis. This perspective article is a call to action for reevaluation of existing strategies and critical appraisal of metformin as first-line therapy in youth-onset type 2 diabetes. Increased attention should be given to novel therapeutics approved in youth, including glucagon-like 1 receptor agonists, sodium glucose cotransporter-2, and sociocultural interventions that will promote diabetes self-management.

The effects of prebiotics on gastrointestinal side effects of metformin in youth: A pilot randomized control trial in youth-onset type 2 diabetes

Disclosure summary

Dr. Yadav is Chief Scientific Officer and Co-Founder of Postbiotics Inc and has no conflict of interest with this work. All other authors have no conflicts of interest to disclose.

Background

Metformin is the only approved first-line oral glucose lowering agent for youth with type 2 diabetes mellitus (Y-T2DM) but often causes gastrointestinal (GI) side effects, which may contribute to reduced treatment adherence and efficacy. Prebiotic intake may reduce metformin's side effects by shifting microbiota composition and activity.

Objective

The aims of this study were to determine the feasibility and tolerability of a prebiotic supplement to improve metformin-induced GI symptoms and explore the changes in glycemia and shifts in the microbiota diversity.

Methods

In a two-phase pilot clinical trial, we compared, stool frequency and stool form every 1-2 days, and composite lower GI symptoms (weekly) at initiation of daily metformin combined with either a daily prebiotic or a placebo shake in a 1-week randomized double-blind crossover design (Phase 1), followed by a 1-month open-labeled extension (Phase 2). Plasma glycemic markers and stool samples were collected before and after each phase.

Results

Six Y-T2DM (17.2 ± 1.7y (mean ± SD), 67% male, BMI (42 ± 9 kg/m2), HbA1c (6.4 ± 0.6%)) completed the intervention. Stool frequency, stool composition, and GI symptom scores did not differ by group or study phase. There were no serious or severe adverse events reported, and no differences in metabolic or glycemic markers. After one week Phase 1metformin/placebo Proteobacteria, Enterobacteriaceae, and Enterobacteriales were identified as candidate biomarkers of metformin effects. Principle coordinate analyses of beta diversity suggested that the metformin/prebiotic intervention was associated with distinct shifts in the microbiome signatures at one week and one month.

Conclusion

Administration of a prebiotic fiber supplement during short-term metformin therapy was well tolerated in Y-T2DM and associated with modest shifts in microbial composition. This study provides a proof-of-concept for feasibility exploring prebiotic-metformin-microbiome interactions as a basis for adjunctive metformin therapy.

Clinical trial registration

https://clinicaltrials.gov/, identifier NCT04209075.

Stimulation of glucose uptake by the natural coenzyme alpha-lipoic acid/thioctic acid: participation of elements of the insulin signaling pathway

Thioctic acid (alpha-lipoic acid), a natural cofactor in dehydrogenase complexes, is used in Germany in the treatment of symptoms of diabetic neuropathy. Thioctic acid improves insulin-responsive glucose utilization in rat muscle preparations and during insulin clamp studies performed in diabetic individuals. The aim of this study was to determine the direct effect of thioctic acid on glucose uptake and glucose transporters. In L6 muscle cells and 3T3-L1 adipocytes in culture, glucose uptake was rapidly increased by (R)-thioctic acid. The increment was higher than that elicited by the (S)-isomer or the racemic mixture and was comparable with that caused by insulin. In parallel to insulin action, the stimulation of glucose uptake by thioctic acid was abolished by wortmannin, an inhibitor of phosphatidylinositol 3-kinase, in both cell lines. Thioctic acid provoked an upward shift of the glucose-uptake insulin dose-response curve. The molar content of GLUT1 and GLUT4 transporters was measured in both cell lines. 3T3-L1 adipocytes were shown to have >10 times more glucose transporters but similar ratios of GLUT4:GLUT1 than L6 myotubes. The effect of (R)-thioctic acid on glucose transporters was studied in the L6 myotubes. Its stimulatory effect on glucose uptake was associated with an intracellular redistribution of GLUT1 and GLUT4 glucose transporters, similar to that caused by insulin, with minimal effects on GLUT3 transporters. In conclusion, thioctic acid stimulates basal glucose transport and has a positive effect on insulin-stimulated glucose uptake. The stimulatory effect is dependent on phosphatidylinositol 3-kinase activity and may be explained by a redistribution of glucose transporters. This is evidence that a physiologically relevant compound can stimulate glucose transport via the insulin signaling pathway.

Regulation of glucose transport and expression of GLUT3 transporters in human circulating mononuclear cells: studies in cells from insulin-dependent diabetic and nondiabetic individuals

We have previously shown that human circulating mononuclear cells (CMCs) respond to physiological concentrations of insulin with a rapid increase in glucose transport rate. The responding cells were found to be the monocytes, and cells derived from individuals with insulin-dependent diabetes mellitus (IDDM) had lower basal and insulin-stimulated glucose transport rates. Of interest, both cell types were found to express the GLUT1 but not the typical insulin-responsive GLUT4 transporter isoform. To further study the mechanisms responsible for stimulation of transport in these cells, we investigated (1) the response to insulin-like growth factor-I (IGF-I) and insulin-mimetic agents, and (2) the expression of other glucose transporter isoforms in CMCs of nondiabetic and IDDM individuals. The time course of insulin-stimulated glucose uptake in CMCs was rapid, reaching a plateau within 30 minutes. CMCs showed a dose-dependent and highly sensitive increase in glucose uptake to IGF-I (maximal response reached at 0.1 to 0.5 nmol/L IGF-I). The IGF-I dose-response curve was similar for CMCs of control and IDDM individuals, but both the basal and maximal response to IGF-I were lower in the diabetic group (P < .01). CMCs did not respond to vanadate, lithium, hydrogen peroxide, or short incubation (1 hour) with metformin, but glucose uptake increased in response to peroxides of vanadate and longer-duration (14 hours) metformin incubations. The glucose transporter isoforms of separated monocytes and lymphocytes were further investigated by Northern blotting of total RNA with a GLUT3-specific cDNA probe and by Western blotting of total membranes using GLUT3-specific antiserum.(ABSTRACT TRUNCATED AT 250 WORDS)