Diverse Strategies for Modulating Insulin Resistance: Causal or Consequential Inference on Metabolic Parameters in Treatment-Naïve Subjects with Type 2 Diabetes.

Bacground and Objectives: The objective of this study is to investigate how different therapies modulating insulin resistance, either causally or consequently, affect metabolic parameters in treatment-naïve subjects with T2DM. Subjects and Methods: A total of 212 subjects were assigned to receive either a tight Japanese diet (n = 65), pioglitazone at doses ranging from 15-30 mg/day (n = 70), or canagliflozin at doses ranging from 50-100 mg/day (n = 77) for a duration of three months. Correlations and changes (Δ) in metabolic parameters relative to insulin resistance were investigated. Results: Across these distinct therapeutic interventions, ΔHOMA-R exhibited significant correlations with ΔFBG and ΔHOMA-B, while demonstrating a negative correlation with baseline HOMA-R. However, other parameters such as ΔHbA1c, ΔBMI, ΔTC, ΔTG, Δnon-HDL-C, or ΔUA displayed varying patterns depending on the treatment regimens. Participants were stratified into two groups based on the median value of ΔHOMA-R: the lower half (X) and upper half (Y). Group X consistently demonstrated more pronounced reductions in FBG compared to Group Y across all treatments, while other parameters including HbA1c, HOMA-B, TC, TG, HDL-C, non-HDL-C, TG/HDL-C ratio, or UA exhibited distinct regulatory responses depending on the treatment administered. Conclusions: These findings suggest that (1) regression to the mean is observed in the changes in insulin resistance across these therapies and (2) the modulation of insulin resistance with these therapies, either causally or consequentially, results in differential effects on glycemic parameters, beta-cell function, specific lipids, body weight, or UA.

Alogliptin: a DPP-4 inhibitor modulating adipose tissue insulin resistance and atherogenic lipid.

AIMS: The purpose of this study is to investigate the regulation of adipose tissue insulin resistance with DPP-4 inhibitors in treatment-naive subjects with T2DM and to examine its relation to other diabetic parameters. SUBJECTS AND METHODS: A total of 147 subjects were treated with alogliptin 12.5-25 mg/day (n = 55), sitagliptin 25-50 mg/day (n = 49), or teneligliptin 10-20 mg/day (n = 43) monotherapy for 3 months. Changes in adipo-IR, a mathematical model used to evaluate adipose tissue insulin resistance, and various diabetic parameters were analyzed in this prospective, non-randomized observational study. RESULTS: Among these three drugs, only alogliptin significantly reduced adipo-IR (-25.9%, p < 0.004) and some lipid parameters, such as LDL-C, T-C/HDL-C, log(TG)/HDL-C, non-HDL-C/HDL-C, and LDL-C/HDL-C. Subjects in the alogliptin group were divided into two groups with distinct changes in adipo-IR. Group A had a significant decrease in adipo-IR (-56.5%, p < 0.00001, n = 28), whereas group B had an insignificant increase (19.1%, p = 0.055, n = 27). Significant reductions in FBG or HbA1c were observed in groups A and B, respectively. Group A also showed significant reductions in HOMA-R, T-C/HDL-C, TG, log(TG)/HDL-C, non-HDL-C/HDL-C, LDL-C/HDL-C, and FFA, as well as increases in QUICKI or HDL-C. In contrast, group B showed significant reductions in QUICKI or LDL-C, and increases in HOMA-R, insulin, HOMA-B, C-peptide, or CPR-index. CONCLUSIONS: In contrast to other tested DPP-4 inhibitors, alogliptin demonstrated the ability to down-regulate insulin resistance in adipose tissue, as well as certain atherogenic lipids. This study provides the initial evidence of a DPP-4 inhibitor's potential to regulate adipose tissue insulin resistance. Furthermore, adipo-IR is associated with non-LDL-C lipid parameters instead of glycemic control in those receiving alogliptin.

Complementary effects on glycaemic and non-glycaemic parameters between responders and non-responders treated with pioglitazone and canagliflozin in drug-naive subjects with type 2 diabetes.

OBJECTIVES: The aim of this study was to investigate the differential regulation of metabolic parameters between pioglitazone and canagliflozin in relation to their glycaemic efficacies. METHODS: Drug-naive subjects with T2DM received pioglitazone 15-30 mg/day or canagliflozin 50-100 mg/day monotherapy for 3 months. Those who had a ≥1% reduction in HbA1c were defined as responders and others who had a <1% reduction were defined as non-responders. RESULTS: In the pioglitazone group, baseline BMI, FFA, HOMA-R or adipo-IR was significantly higher, and HDL-C was significantly lower in responders vs non-responders. In the canagliflozin group, baseline HbA1c or FBG was significantly higher, and HOMA-B or age was significantly lower in responders vs non-responders. In pioglitazone responders, significant decreases in HbA1c (from 10.75% to 8.31%), FBG (-29.7%), FFA (-37.7%), non-HDL-C (-13.4%), TG (-30.1%), HOMA-R (-35.6%) or adipo-IR (-38.7%), and increases in BMI (2.8%) or HDL-C (14.2%) were observed. In pioglitazone non-responders, none of the parameters were regulated. In canagliflozin responders, significant decreases in HbA1c (from 11.31% to 8.60%), FBG (32.1%), BMI (-2%) or HOMA-R (-33.8%), and increases in HOMA-B (50%) were observed. In canagliflozin non-responders, significant decreases in BMI (-2.4%), insulin (-21.8%) or HOMA-R (-33.6%) were observed. CONCLUSIONS: (i) Glycaemic efficacy of pioglitazone is linked to body weight and atherogenic lipids while this is not the case with canagliflozin. (ii) Responders (or non-responders) to pioglitazone have some distinct features from non-responders (or responders) to canagliflozin. Collectively, a combination of pioglitazone and canagliflozin may compensate for each other's metabolic drawbacks or augment their advantages, thereby achieving overall improvements in the metabolic profiles and pathogenic defects of patients with T2DM.

Regulation of Adipose Tissue Insulin Resistance and Diabetic Parameters in Drug Naïve Subjects with Type 2 Diabetes Treated with Canagliflozin Monotherapy.

The objective of this study is to investigate the link between the baseline/changes of body weight and those of diabetic parameters during treatment with an SGLT-2 inhibitor. Drug naïve subjects with T2DM received canagliflozin monotherapy for 3 months. Adipo-IR was selected as the significant factor responsible for the changes of (Δ)BMI with this drug. While no correlations were noted between ΔBMI and ΔFBG, ΔHbA1c, ΔHOMA-R or ΔQUICKI, significant negative correlations were observed between ΔBMI and Δadipo-IR (R=-0.308). The subjects were divided into two groups with baseline BMI<25 (n=31, group alpha) or≥25 (n=39, group beta). Baseline levels of FBG, HbA1c, T-C, TG, non-HDL-C, LDL-C showed no differences between group alpha and beta. The subjects were also divided into two equal numbers of subjects (n=35 each) based on the changes of weight: the lower half (-3.6%, p<0.00001, group A) and the upper half (0.1%, n.s., group B) of ∆BMI. FBG, HbA1c or HOMA-R significantly, similarly decreased, while QUICKI increased in group A and B. TG significantly decreased, while HDL-C increased in group A. HOMA-B significantly increased, while adipo-IR insignificantly decreased in group B. Collectively, these results suggest that 1) adipose tissue insulin resistance is responsible for the weight changes with canagliflozin. 2) baseline levels of glycemic and some lipid parameters were similar between obese and non-obese populations. 3) weight changes with canagliflozin were not associated with its glycemic or insulin sensitizing efficacies but were linked to adipose-tissue insulin resistance, some lipids, and beta-cell function.

Regulations of Free Fatty Acids and Diabetic Parameters in Drug Naïve Subjects with Type 2 Diabetes Treated with Canagliflozin Monotherapy.

The objective of this study is to investigate the regulations of FFA with canagliflozin in relation to metabolic parameters. Drug naïve subjects with T2DM were administered 50-100 mg/day canagliflozin monotherapy (n=70) for 3 months. Significant correlations between the changes of (Δ) FFA and Δadipo-IR (R=0.496), but no correlations between ΔFFA and ΔHOMA-R were observed. The subjects were divided into three groups with similar numbers according to Δ FFA: group A: highest tertile: (ΔFFA=38.7%, n=23); group B: intermediate tertile: (ΔFFA=2%, n=23); group C: lowest tertile: (ΔFFA=-36%, n=24). Metabolic parameters were compared between group A and group C. At baseline, FFA was higher in group C than group A (p<0.002). Greater degrees of HbA1c reduction and increases of insulin were observed in group C than group A (both p<0.05). In group A, significant reductions of BMI (-2.6%) and HOMA-R (-30%) were seen. In group C, significant reductions of non-HDL-C (-6.2%), UA (-7.6%) or adipo-IR (-28.7%), and increases of HOMA-B (+85.6%) were observed. Taken together, 1) certain population treated with canagliflozin showed decreased FFA. 2) beta-cell function increased while atherogenic cholesterol, UA and adipo-IR decreased in those with reduced FFA. Better glycemic efficacies were seen in these populations. 3) body weight and whole body insulin resistance (HOMA-R) significantly decreased in those with elevated FFA. 4) FFA is linked to adipose insulin resistance (adipo-IR), while it does not appear to impact whole body insulin resistance (HOMA-R).

Link between serum uric acid and pancreatic beta-cell function in drug naïve subjects with type 2 diabetes treated with sitagliptin.

Aim: The objective of this study is to investigate the changes of UA with sitagliptin in relation to its glycemic/non-glycemic efficacies.Methods: Drug naïve subjects with T2DM (n = 62) were administered 25-50 mg/day sitagliptin monotherapy for 3 months. The subjects were divided into two subgroups according to the changes in (Δ) UA (above the median [group A, n = 31]: ΔUA = 23.3%, p < 0.00001, and below the median [group B, n = 31]: ΔUA = -0.9%, n.s.). Changes in glycemic/non-glycemic parameters were compared between these two groups, which acted as a control for each other.Results: In the overall subjects, UA significantly increased (10.8%, p < 0.00001). Significant correlations between ΔUA and ΔBMI (R = 0.252), ΔHOMA-B (R = 0.309) or ΔCPR-index (R = 0.258), and significant negative correlations between ΔUA and ΔHbA1c (R = -0.290) or ΔFFA (R = -0.271) were seen. Between group A and group B, some parameters displayed distinct regulatory patterns. HbA1c significantly decreased in both groups (group A: from 9.97% to 7.65%, group B: from 10.41% to 8.85%) with significant inter-group differences (higher reductions in group A, p < 0.05). C-peptide (+10.6%) and BMI (+1.7%) significantly increased, and FFA (-20.5%) decreased in group A. HOMA-R or 20/(C-peptide x FBG) had no changes in either group, while HOMA-B (group A: +85.1%, group B: +38.8%) or CPR-index (group A: +37.7%, group B: +20.5%) increased in both groups with significant inter-group differences (both p < 0.01). TG (-18.8%) significantly decreased, and T-C (-3.5%) and non-HDL-C (-4%) had a tendency to decrease in group B.Conclusions: These results suggest that UA and beta-cell functions/glycemic efficacy are closely linked during sitagliptin therapy. Those with elevated UA had better beta-cell enhancing and glyemic efficacies. Body weights increased and FFA decreased in these populations. By contrast, those without changes in UA had favorable profiles in atherogenic lipids.

Sitagliptin as an Initial Therapy and Differential Regulations of Metabolic Parameters Depending on its Glycemic Response in Subjects with Type 2 Diabetes.

The aim of this study is to investigate whether sitagliptin can be used as an initial drug for T2DM and to evaluate its effects on metabolic parameters in relation to its glycemic efficacies. The subjects received 25-50 mg/day sitagliptin monotherapy (n=69). At 3 months, they were divided into three groups (n=23 each) according to the novel parameter called "A1c index" which is designed to assess glycemic efficacy. The metabolic parameters were compared between good-responders and poor-responders. These two groups acted as a control each other. In the overall subjects, efficient reductions of HbA1c (10.16-8.22%) were observed with few adverse events. Significant correlations were seen between the A1c index and changes of (∆)nonHDL-C (R=0.250) or ∆LDL-C (R=0.368). At baseline, T-C, nonHDL-C and BMI levels were significantly lower in good-responders than poor-responders. At 3 months, in good-responders, HbA1c levels effectively decreased (11.03-7.00%). Indexes for insulin sensitivity/resistance [HOMA-R and 20/(C-peptide x FBG)] and beta-cell function (HOMA-B and CPR-index) ameliorated. T-C, nonHDL-C and LDL-C significantly decreased, while BMI increased. However, in poor-responders, no changes in these parameters were noted. Collectively, these results suggest that 1) Sitagliptin can be used as a first-line drug for T2DM and its glycemic efficacy is linked to some atherogenic lipids. 2) Those with lower T-C, nonHDL-C and BMI appear to respond better with this drug. 3) Good glycemic efficacy of sitagliptin is medicated through reduced insulin resistance as well as enhanced beta-cell functions. Body weight increased, while some atherogenic cholesterol decreased in good-responders.

Link between body weight changes and metabolic parameters in drugs naïve subjects with type 2 diabetes treated with canagliflozin monotherapy.

OBJECTIVES: The aim of this study is to investigate the correlations between the changes of body weight and metabolic parameters during canagliflozin treatment. METHODS: Drug naïve subjects with T2DM (n = 84) received canagliflozin monotherapy for 3 months. The subjects were divided into three groups with equal numbers of subjects (n = 28 each) according to the reductions of BMI levels; highest (group A), intermediate (group B), and lowest (group C) reductions. Changes of the metabolic parameters were compared between group A and group C. These two groups acted as a control of each other. RESULTS: Significant reductions of BMI levels (-4.1%, p < 0.00001) were observed in group A, while, surprisingly, significant increases (+1.5%, p < 0.00001) were seen in group C. In these two groups, similar reductions of HbA1c, FBG, or HOMA-R, and increases of HOMA-B levels were observed. Significant reductions of TG levels (-18.6%) were seen only in group A. At baseline, HbA1c levels were significantly lower in group A versus group C (p < 0.03). In group A, significant correlations between the changes of BMI and those of HbA1c (R = 0.496) were seen. By contrast, in group C, significant negative correlations were observed between these parameters (R = -0.463). CONCLUSIONS: These results suggest that certain populations treated with canagliflozin gained weight, though similar glycemic and beta-cell/insulin sensitivity enhancing properties were observed in comparison to those with efficient weight reductions. Those who lost more weight had better glycemic efficacy in group A. By contrast, those who gained more weight had better glycemic efficacy in group C. Distinct glucose-lowering mechanisms might be operating between these two groups. Involvement of some factors including glucagons and free fatty acids is hypothesized.