Glucose effectiveness: Lessons from studies on insulin-independent glucose clearance in mice

Mixed-Lineage Leukaemia Gene Regulates Glucose-Sensitive Gene Expression and Insulin Secretion in Pancreatic Beta Cells

The escalating prevalence of diabetes mellitus underscores the need for a comprehensive understanding of pancreatic beta cell function. Interest in glucose effectiveness has prompted the exploration of novel regulatory factors. The myeloid/lymphoid or mixed-lineage leukaemia gene (MLL) is widely recognised for its role in leukemogenesis and nuclear regulatory mechanisms through its histone methyltransferase activity in active chromatin. However, its function within pancreatic endocrine tissues remains elusive. Herein, we unveil a novel role of MLL in glucose metabolism and insulin secretion. MLL knockdown in βHC-9 pancreatic beta cells diminished insulin secretion in response to glucose loading, paralleled by the downregulation of the glucose-sensitive genes SLC2a1 and SLC2a2. Similar observations were made in MLL heterozygous knockout mice (MLL+/-), which exhibited impaired glucose tolerance and reduced insulin secretion without morphological anomalies in pancreatic endocrine cells. The reduction in insulin secretion was independent of changes in beta cell mass or insulin granule morphology, suggesting the regulatory role of MLL in glucose-sensitive gene expression. The current results suggest that MLL interacts with circadian-related complexes to modulate the expression of glucose transporter genes, thereby regulating glucose sensing and insulin secretion. Our findings shed light on insulin secretion control, providing potential avenues for therapeutics against diabetes.

Total Pancreatectomy in a Patient Treated with a Sensor-augmented Pump Showing No Evidence of Hyperglycemia or Ketoacidosis without Any Insulin Administration

Total pancreatectomy results in complete loss of insulin and glucagon. Sensor-augmented pumps (SAPs) allow fine-tuning of the basal insulin rate, which helps avoid both hypo- and hyperglycemic events. We herein report a case of total pancreatectomy treated with a SAP with no evidence of ketoacidosis without any insulin administration during a certain period of time. Furthermore, we observed a sudden drop in blood glucose levels without insulin, which may have been due to glucose effectiveness. Our case is valuable in arguing the concept of glucose effectiveness in the absence of insulin and glucagon.

The dual incretin co-agonist tirzepatide increases both insulin secretion and glucose effectiveness in model experiments in mice

Tirzepatide is a dual GIP and GLP-1 receptor co-agonist which is approved for glucose-lowering therapy in type 2 diabetes. Here, we explored its effects on beta cell function, insulin sensitivity and insulin-independent glucose elimination (glucose effectiveness) in normal mice. Anesthetized female C57/BL/6 J mice were injected intravenously with saline or glucose (0.125, 0.35 or 0.75 g/kg) with or without simultaneous administration of synthetic tirzepatide (3 nmol/kg). Samples were taken at 0, 1, 5, 10, 20 and 50 min. Glucose elimination rate was estimated by the percentage reduction in glucose from min 5 to min 20 (KG). The 50 min areas under the curve (AUC) for insulin and glucose were determined. Beta cell function was assessed as AUCinsulin divided by AUCglucose. Insulin sensitivity (SI) and glucose effectiveness (SG) were determined by minimal model analysis of the insulin and glucose data. Tirzepatide glucose-dependently reduced glucose levels and increased insulin levels. The slope for the regression of AUCinsulin versus AUCglucose was increased 7-fold by tirzepatide from 0.014 ± 0.004 with glucose only to 0.099 ± 0.016 (P < 0.001). SI was not affected by tirzepatide, whereas SG was increased by 78% (P < 0.001). The increase in SG contributed to an increase in KG by 74 ± 4% after glucose alone and by 67 ± 8% after glucose+ tirzepatide, whereas contribution by SI times AUCinsulin insulin (i.e., disposition index) was 26 ± 4% and 33 ± 8%, respectively. In conclusion, tirzepatide stimulates both insulin secretion and glucose effectiveness, with stimulation of glucose effectiveness being the prominent process to reduce glucose.

Pressure-Driven Insulin Release Overcomes Limitations of Diffusion for Encapsulated Islet Cell Therapy

Cadaveric islet and stem cell-derived transplantation show great promise as therapeutic approaches for type 1 diabetes. To address the immunocompatibility challenge, numerous cellular macroencapsulation techniques, which rely upon diffusion to transport insulin across the immunoprotective barrier, have been proposed. Although several of these devices were advanced to human clinical trials, they uniformly failed to achieve physiologic glucose control or insulin independence. Indeed, based upon mathematical modeling and empiric evidence, diffusion-based encapsulation devices are fundamentally incompatible with homeostatic on-demand insulin delivery and physiologic glucose regulation. To realize the potential of achieving insulin independence through macroencapsulated cell-based therapy, we propose the necessity of a second driving force. Herein, we provide both theoretical proof and experimental demonstration that modest (11-kPa) micropump-applied pressure considerably enhances insulin flux across immunoisolation membranes by nearly three orders of magnitude, enabling precise delivery of both bolus and basal insulin. Furthermore, pressure-driven insulin efflux from encapsulated mouse and human islets is fast and repeatable. As such, we urge caution against further advancement of diffusion-based immune-isolating macroencapsulation devices that do not incorporate a secondary driving force for precise temporal regulation of peptide delivery.

One Sentence Summary

Diffusion-based insulin delivery from macroencapsulated islet cells is incompatible with physiologic glucose control, a constraint addressed through pressure-based insulin delivery.

Sumatriptan, a serotonin 5HT1B receptor agonist, acutely reduces insulin secretion and sensitivity and glucose effectiveness in overweight humans: A double-blinded placebo-controlled cross-over trial

AIM

Evidence from mouse models suggests that brain serotonergic pathways control blood glucose. We hypothesized that sumatriptan (5HT1B -receptor agonist) would alter glucose homeostasis in humans.

MATERIALS AND METHODS

We conducted a two-visit random-order double-blinded placebo-controlled cross-over trial in 10 overweight adults that were otherwise healthy. Participants received sumatriptan (single dose, 100 mg) or placebo before undergoing a 60-min intravenous glucose tolerance test, followed by a 120-min hyperinsulinaemic euglycaemic clamp.

RESULTS

Glucose excursion was greater during intravenous glucose tolerance test with sumatriptan compared with placebo [iAUC0-60 min 316 (268-333) vs. 251 (197-319) min/mmol/L p = .047]. This was probably explained by a combination of reduced circulating insulin levels [iAUC0-10 min 1626 (1103-2733) vs. 2336 (1702-3269) min/pmol/L, p = .005], reduced insulin sensitivity [M/I-value 2.11 (1.15, 4.05) vs. 3.03 (1.14, 4.90) mg/kg/min per pmol/L, p = .010] and glucose effectiveness [SG 0.17 (0.12, 0.21) vs. 0.22 (0.18, 0.65)/min, p = .027].

CONCLUSIONS

5HT1B receptors have a glucoregulatory role in humans, probably acting on insulin secretion, insulin sensitivity and glucose effectiveness.

O304 ameliorates hyperglycemia in mice by dually promoting muscle glucose effectiveness and preserving β-cell function

Although insulin mediated glucose uptake in skeletal muscle is a major mechanism ensuring glucose disposal in humans, glucose effectiveness, i.e., the ability of glucose itself to stimulate its own uptake independent of insulin, accounts for roughly half of the glucose disposed during an oral glucose tolerance test. Both insulin dependent and insulin independent skeletal muscle glucose uptake are however reduced in individuals with diabetes. We here show that AMPK activator O304 stimulates insulin independent glucose uptake and utilization in skeletal muscle and heart in vivo, while preventing glycogen accumulation. Combined glucose uptake and utilization requires an increased metabolic demand and we show that O304 acts as a mitochondrial uncoupler, i.e., generates a metabolic demand. O304 averts gene expression changes associated with metabolic inflexibility in skeletal muscle and heart of diabetic mice and reverts diabetic cardiomyopathy. In Type 2 diabetes, insulin resistance elicits compensatory insulin hypersecretion, provoking β-cell stress and eventually compensatory failure. In db/db mice O304 preserves β-cell function by preventing decline in insulin secretion, β-cell mass, and pancreatic insulin content. Thus, as a dual AMPK activator and mitochondrial uncoupler O304 mitigates two central defects of T2D; impaired glucose uptake/utilization and β-cell failure, which today lack effective treatment.

Subclinical Reactive Hypoglycemia with Low Glucose Effectiveness-Why We Cannot Stop Snacking despite Gaining Weight

Obesity has grown worldwide owing to modern obesogenic lifestyles, including frequent snacking. Recently, we studied continuous glucose monitoring in obese/overweight men without diabetes and found that half of them exhibit glucose levels less than 70 mg/dL after a 75-g oral glucose load without notable hypoglycemic symptoms. Interestingly, people with "subclinical reactive hypoglycemia (SRH)" snack more frequently than those without it. Since the ingestion of sugary snacks or drinks could further induce SRH, a vicious cycle of "Snacking begets snacking via SRH" can be formed. Glucose effectiveness (Sg) is an insulin-independent mechanism that contributes to most of the whole-body glucose disposal after an oral glucose load in people without diabetes. Our recent data suggest that both higher and lower Sg are associated with SRH, while the latter but not the former is linked to snacking habits, obesity, and dysglycemia. The present review addresses the possible role of SRH in snacking habits in people with obesity/overweight, taking Sg into account. It is concluded that, for those with low Sg, SRH can be regarded as a link between snacking and obesity. Prevention of SRH by raising Sg might be key to controlling snacking habits and body weight.

Intermittent Fasting Resolves Dyslipidemia and Atherogenesis in Apolipoprotein E-Deficient Mice in a Diet-Dependent Manner, Irrespective of Sex

In humans and animal models, intermittent fasting (IF) interventions promote body weight loss, improve metabolic health, and are thought to lower cardiovascular disease risk. However, there is a paucity of reports on the relevance of such nutritional interventions in the context of dyslipidemia and atherosclerotic cardiovascular diseases. The present study assessed the metabolic and atheroprotective effects of intermittent fasting intervention (IF) in atherosclerosis-prone apolipoprotein E-deficient (Apoe^-/-) mice. Groups of male and female Apoe^-/- mice were fed a regular (chow) or atherogenic (high-fat, high-cholesterol, HFCD) diet for 4 months, either ad libitum or in an alternate-day fasting manner. The results show that IF intervention improved glucose and lipid metabolism independently of sex. However, IF only decreased body weight gain in males fed chow diet and differentially modulated adipose tissue parameters and liver steatosis in a diet composition-dependent manner. Finally, IF prevented spontaneous aortic atherosclerotic lesion formation in mice fed chow diet, irrespective of sex, but failed to reduce HFCD-diet-induced atherosclerosis. Overall, the current work indicates that IF interventions can efficiently improve glucose homeostasis and treat atherogenic dyslipidemia, but a degree of caution is warranted with regard to the individual sex and the composition of the dietary regimen.

Lower Glucose Effectiveness Is Associated with Postprandial Hyperglycemia in Obese/Overweight Men, Independently of Insulin Secretion

The role of glucose effectiveness on postprandial hyperglycemia in daily life is not fully studied. Here, we examined the association between SgIo, an index of glucose effectiveness calculated from a 75 g oral glucose tolerance test, and the indices of hyperglycemia in obese/overweight men. SgIo was significantly associated with 1,5-anhydroglycitol, a biochemical marker for postprandial hyperglycemia. The receiver operating characteristic analyses of SgIo and oral disposition index for detecting the subjects with 1,5-anhydroglycitol < 14 μg/mL revealed that the areas under the curves were 0.77 and 0.76, while the cutoff points (sensitivity, selectivity) were 2.53 (0.9, 0.7) and 2.06 (0.36, 0.79), respectively. Both the SgIo < 2.53 category and the disposition index < 2.06 category were significantly associated with the percentages of meals with postprandial glucose levels ≥ 200 mg/dL, and the percentages of time when continuous glucose monitoring sensor readings were ≥200 mg/dL. After adjustment with disposition index, 45.5% of the subjects with the SgIo < 2.53 category had their 1,5-anhydroglycitol < 14 μg/mL, while, in the SgIo ≥ 2.53 category, 3.6% of the subjects had the hyperglycemia (p < 0.001). In addition, there were tendencies toward higher and lower SgIo quartile categories in subjects with walking (≥8000 steps) ≥60% of days and with noodle ingestion ≥20% of meals, respectively (p for trend, 0.008 and 0.038). In conclusion, lower glucose effectiveness is associated with postprandial hyperglycemia in the daily life of obese/overweight men, independently of insulin secretion. Lifestyles such as habits of walking and noodle ingestion are significantly associated with higher and lower glucose effectiveness, respectively.

The Glucose Sensitivity of Insulin Secretion-Lessons from In Vivo and In Vitro Studies in Mice

This study explored the relationship between the glucose dose and insulin response from beta cells in vivo and in vitro in mice. Glucose was administered intravenously at different dose levels (from 0 to 0.75 g/kg) in anesthetized C57BL/6J mice, and the glucose and insulin concentrations were determined in samples taken after 50 min. Furthermore, freshly isolated mouse islets were incubated for 60 min in the presence of different concentrations of glucose (from 2.8 to 22.2 mmol/L) and insulin levels were analyzed in the medium. It was found that insulin levels increased after an intravenous injection of glucose with the maximal increase seen after 0.35 g/kg with no further increase after 0.5 or 0.75 g/kg. The acute increase in insulin levels (during the first 5 min) and the maximum glucose level (achieved after 1 min) showed a curvilinear relation with the half-maximal increase in insulin levels achieved at 11.4 mmol/L glucose and the maximal increase in insulin levels at 22.0 mmol/L glucose. In vitro, there was also a curvilinear relation between glucose concentrations and insulin secretion. Half maximal increase in insulin concentrations was achieved at 12.5 mmol/L glucose and the maximal increase in insulin concentrations was achieved at 21.5 mmol/L. Based on these data, we concluded that the glucose-insulin relation was curvilinear both in vivo and in vitro in mice with similar characteristics in relation to which glucose levels that achieve half-maximal and maximal increases in insulin secretion. Besides the new knowledge of knowing these relations, the results have consequences on how to design studies on insulin secretion to obtain the most information.

MOTS-c increases in skeletal muscle following long-term physical activity and improves acute exercise performance after a single dose

Skeletal muscle adapts to aerobic exercise training, in part, through fast-to-slow phenotypic shifts and an expansion of mitochondrial networks. Recent research suggests that the local and systemic benefits of exercise training also may be modulated by the mitochondrial-derived peptide, MOTS-c. Using a combination of acute and chronic exercise challenges, the goal of the present study was to characterize the interrelationship between MOTS-c and exercise. Compared to sedentary controls, 4-8 weeks of voluntary running increased MOTS-c protein expression ~1.5-5-fold in rodent plantaris, medial gastrocnemius, and tibialis anterior muscles and is sustained for 4-6 weeks of detraining. This MOTS-c increase coincides with elevations in mtDNA reflecting an expansion of the mitochondrial genome to aerobic training. In a second experiment, a single dose (15 mg/kg) of MOTS-c administered to untrained mice improved total running time (12% increase) and distance (15% increase) during an acute exercise test. In a final experiment, MOTS-c protein translocated from the cytoplasm into the nucleus in two of six mouse soleus muscles 1 h following a 90-min downhill running challenge; no nuclear translocation was observed in the plantaris muscles from the same animals. These findings indicate that MOTS-c protein accumulates within trained skeletal muscle likely through a concomitant increase in mtDNA. Furthermore, these data suggest that the systemic benefits of exercise are, in part, mediated by an expansion of the skeletal muscle-derived MOTS-c protein pool. The benefits of training may persist into a period of inactivity (e.g., detraining) resulting from a sustained increase in intramuscular MOTS-c proteins levels.

Comparative analysis of oral and intraperitoneal glucose tolerance tests in mice

Objective

The glucose tolerance test (GTT) is widely used in preclinical research to investigate glucose metabolism, but there is no standardised way to administer glucose. The aim of this study was to directly compare the effect of the route of glucose administration on glucose and insulin kinetics during a GTT in mice.

Methods

A GTT was performed in lean male and female mice and obese male mice and glucose was administered via the oral or intraperitoneal (I.P.) route. Samples were collected frequently during the GTT to provide a full time-course of the insulin and glucose excursions. In another cohort of lean male mice, plasma concentrations of insulin, c-peptide, and incretin hormones were measured at early time points after glucose administration. A stable-isotope labelled GTT (SiGTT) was then performed to delineate the contribution of exogenous and endogenous glucose to glycemia during the GTT, comparing both methods of glucose administration. Finally, we present a method to easily measure insulin from small volumes of blood during a GTT by directly assaying whole-blood insulin using ELISA and show a good concordance between whole-blood and plasma insulin measurements.

Results

We report that I.P. glucose administration results in an elevated blood glucose excursion and a largely absent elevation in blood insulin and plasma incretin hormones when compared to oral administration. Utilising stable-isotope labelled glucose, we demonstrate that the difference in glucose excursion between the two routes of administration is mainly due to the lack of suppression of glucose production in I.P. injected mice. Additionally, rates of exogenous glucose appearance into circulation were different between lean and obese mice after I.P., but not after oral glucose administration.

Conclusion

Reflecting on these data, we suggest that careful consideration be given to the route of glucose administration when planning a GTT procedure in mice and that in most circumstances the oral route of glucose administration should be preferred over the I.P. route to avoid possible artifacts originating from a non-physiological route.

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Intraperitoneal glucose administration does not promote insulin secretion.

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Exogenous glucose appearance is delayed in obese mice after intraperitoneal administration.

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Hepatic glucose production is suppressed after administering oral not intraperitoneal glucose.

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Measuring insulin from whole blood is comparable to that from plasma.

Paul AK, Autieri MV, Scalia R, Rizzo V, Hashimoto T, Eguchi S. Glucose consumption of vascular cell types in culture: toward optimization of experimental conditions

In this study, we have looked for an optimum media glucose concentration and compared glucose consumption in three vascular cell types, endothelial cells (ECs), vascular smooth muscle cells (VSMCs), and adventitial fibroblasts (AFs) with or without angiotensin II (AngII) stimulation. In a subconfluent 6-well experiment in 1 mL DMEM with a standard low (100 mg/dL), a standard high (450 mg/dL), or a mixed middle (275 mg/dL) glucose concentration, steady and significant glucose consumption was observed in all cell types. After 48-h incubation, media that contained low glucose was reduced to almost 0 mg/dL, media that contained high glucose remained significantly higher at ∼275 mg/dL, and media that contained middle glucose remained closer to physiological range. AngII treatment enhanced glucose consumption in AFs and VSMCs but not in ECs. Enhanced extracellular acidification rate by AngII was also observed in AFs. In AFs, AngII induction of target proteins at 48 h varied depending on the glucose concentration used. In low glucose media, induction of glucose regulatory protein 78 or hexokinase II was highest, whereas induction of VCAM-1 was lowest. Utilization of specific inhibitors further suggests essential roles of angiotensin II type-1 receptor and glycolysis in AngII-induced fibroblast activation. Overall, this study demonstrates a high risk of hypo- or hyperglycemic conditions when standard low or high glucose media is used with vascular cells. Moreover, these conditions may significantly alter experimental outcomes. Media glucose concentration should be monitored during any culture experiments and utilization of middle glucose media is recommended for all vascular cell types.

β-Cell Knockout of SENP1 Reduces Responses to Incretins and Worsens Oral Glucose Tolerance in High-Fat Diet-Fed Mice

SUMOylation reduces oxidative stress and preserves islet mass at the expense of robust insulin secretion. To investigate a role for the deSUMOylating enzyme sentrin-specific protease 1 (SENP1) following metabolic stress, we put pancreas/gut-specific SENP1 knockout (pSENP1-KO) mice on a high-fat diet (HFD). Male pSENP1-KO mice were more glucose intolerant following HFD than littermate controls but only in response to oral glucose. A similar phenotype was observed in females. Plasma glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide 1 (GLP-1) responses were identical in pSENP1-KO and wild-type littermates, including the HFD-induced upregulation of GIP responses. Islet mass was not different, but insulin secretion and β-cell exocytotic responses to the GLP-1 receptor agonist exendin-4 (Ex4) and GIP were impaired in islets lacking SENP1. Glucagon secretion from pSENP1-KO islets was also reduced, so we generated β-cell-specific SENP1 KO mice. These phenocopied the pSENP1-KO mice with selective impairment in oral glucose tolerance following HFD, preserved islet mass expansion, and impaired β-cell exocytosis and insulin secretion to Ex4 and GIP without changes in cAMP or Ca²⁺ levels. Thus, β-cell SENP1 limits oral glucose intolerance following HFD by ensuring robust insulin secretion at a point downstream of incretin signaling.

The Role of Incretins on Insulin Function and Glucose Homeostasis

The incretin effect-the amplification of insulin secretion after oral vs intravenous administration of glucose as a mean to improve glucose tolerance-was suspected even before insulin was discovered, and today we know that the effect is due to the secretion of 2 insulinotropic peptides, glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1). But how important is it? Physiological experiments have shown that, because of the incretin effect, we can ingest increasing amounts of amounts of glucose (carbohydrates) without increasing postprandial glucose excursions, which otherwise might have severe consequences. The mechanism behind this is incretin-stimulated insulin secretion. The availability of antagonists for GLP-1 and most recently also for GIP has made it possible to directly estimate the individual contributions to postprandial insulin secretion of a) glucose itself: 26%; b) GIP: 45%; and c) GLP-1: 29%. Thus, in healthy individuals, GIP is the champion. When the action of both incretins is prevented, glucose tolerance is pathologically impaired. Thus, after 100 years of research, we now know that insulinotropic hormones from the gut are indispensable for normal glucose tolerance. The loss of the incretin effect in type 2 diabetes, therefore, contributes greatly to the impaired postprandial glucose control.

Impact of Incretin Hormone Receptors on Insulin-Independent Glucose Disposal in Model Experiments in Mice

A large contribution to glucose elimination from the circulation is achieved by insulin-independent processes. We have previously shown that the two incretin hormones, glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1) increase this process and, therefore, seem to contribute to glucose disposal both through this effect and through the classical incretin effect resulting in enhanced insulin levels. We have now explored in more detail the potential contribution by incretin hormone receptors to insulin-independent processes for glucose elimination. To that end, we have performed intravenous glucose tests (0.35g/kg) in C57BL/6J mice and analyzed glucose elimination rate and glucose effectiveness (i.e., insulin-independent glucose disposal, SG) in wildtype mice and in mice with genetic deletion of GIP receptors or GLP-1 receptors. We performed studies with or without complete blockade of insulin secretion by the drug diazoxide (25 mg/kg). The mice were anesthetized with a novel fentanyl citrate/fluanisone formulation, called Fluafent, together with midazolam. Initially we demonstrated that glucose and insulin data after intravenous and oral glucose were not different using this anesthesia compared to the previously commonly used combination of HypnormR and midazolam. The results show that SG was reduced in GLP-1 receptor knockout mice, whereas there was no difference between GIP receptor knockout mice and wildtype mice, and this was evident both under normal conditions and after complete inhibition of insulin secretion. The study therefore indicates that insulin-independent glucose elimination requires active GLP-1 receptors and thus that the two incretin hormone receptor types show dissociated relevance for this process.

An Analysis of Glucose Effectiveness in Subjects With or Without Type 2 Diabetes via Hierarchical Modeling

Glucose effectiveness, defined as the ability of glucose itself to increase glucose utilization and inhibit hepatic glucose production, is an important mechanism maintaining normoglycemia. We conducted a minimal modeling analysis of glucose effectiveness at zero insulin (GEZI) using intravenous glucose tolerance test data from subjects with type 2 diabetes (T2D, n=154) and non-diabetic (ND) subjects (n=343). A hierarchical statistical analysis was performed, which provided a formal mechanism for pooling the data from all study subjects, to yield a single composite population model that quantifies the role of subject specific characteristics such as weight, height, age, sex, and glucose tolerance. Based on the resulting composite population model, GEZI was reduced from 0.021 min-1 (standard error - 0.00078 min-1) in the ND population to 0.011 min-1 (standard error - 0.00045 min-1) in T2D. The resulting model was also employed to calculate the proportion of the non-insulin-dependent net glucose uptake in each subject receiving an intravenous glucose load. Based on individual parameter estimates, the fraction of total glucose disposal independent of insulin was 72.8% ± 12.0% in the 238 ND subjects over the course of the experiment, indicating the major contribution to the whole-body glucose clearance under non-diabetic conditions. This fraction was significantly reduced to 48.8% ± 16.9% in the 30 T2D subjects, although still accounting for approximately half of the total in the T2D population based on our modeling analysis. Given the potential application of glucose effectiveness as a predictor of glucose intolerance and as a potential therapeutic target for treating diabetes, more investigations of glucose effectiveness in other disease conditions can be conducted using the hierarchical modeling framework reported herein.