Practical strategies for improving outcomes in T2DM: The potential role of pioglitazone and DPP4 inhibitors

Efficacy and safety of fixed dose combination of Sitagliptin, metformin, and pioglitazone in type 2 Diabetes (IMPACT study): a randomized controlled trial

BACKGROUND

Due to the progressive decline in β-cell function, it is often necessary to utilize multiple agents with complementary mechanisms of action to address various facets and achieve glycemic control. Thus, this study aimed to evaluate the efficacy and safety of a fixed-dose combination (FDC) of metformin/sitagliptin/pioglitazone (MSP) therapy vs. metformin/sitagliptin (MS) in type 2 diabetes mellitus (T2DM).

METHODS

In this phase 3, multicenter, double-blind study, patients with T2DM who exhibited inadequate glycemic control with HbA1c of 8.0-11.0% while taking ≥1500 mg/day metformin for at least 6 weeks were randomized to receive either FDC of MSP (1000/100/15 mg) or MS (1000/100 mg) per day for 24 weeks. The primary outcome measure was the change in HbA1c, and secondary outcomes included changes in fasting plasma glucose (FPG), postprandial plasma glucose (PPG), and body weight from baseline to 24 weeks along with safety and tolerability.

RESULTS

Among the 236 patients randomized, 207 (87.71%) successfully completed the study. All baseline characteristics were comparable between the FDC of MSP and MS groups. There was a subsequent significant reduction of HbA1c in FDC of MSP (- 1.64) vs. MS (- 1.32); between groups was [- 0.32% (95% CI, - 0.59, - 0.05)], P = 0.0208. Similar reductions were found in FPG [- 13.2 mg/dL (95% CI, - 22.86, - 3.71)], P = 0.0068, and PPG [- 20.83 mg/dL (95% CI, - 34.11, - 7.55)], P = 0.0023. There were no significant changes in body weight. A total of 27 adverse effects (AEs) and one severe AE were reported, none of which were related to the study drug.

CONCLUSION

The FDC of MSP demonstrated significant efficacy in managing glycemic indices and could serve as a valuable tool for physicians in the management of Indian patients with T2DM.

TRIAL REGISTRATION

Clinical Trials Registry of India, CTRI/2021/10/037461.

Gut Microbiota: Therapeutic Targets of Ginseng Against Multiple Disorders and Ginsenoside Transformation

Panax ginseng, as the king of Chinese herb, has significant therapeutic effects on obesity, type 2 diabetes mellitus, fatty liver disease, colitis, diarrhea, and many other diseases. This review systematically summarized recent findings, which show that ginseng plays its role by regulating gut microbiota diversity, and gut microbiota could also regulate the transformation of ginsenosides. We conclude the characteristics of ginseng in regulating gut microbiota, as the potential targets to prevent and treat metabolic diseases, colitis, neurological diseases, cancer, and other diseases. Ginseng treatment can increase some probiotics such as Bifidobacterium, Bacteroides, Verrucomicrobia, Akkermansia, and reduce pathogenic bacteria such as Deferribacters, Lactobacillus, Helicobacter against various diseases. Meanwhile, Bacteroides, Eubacterium, and Bifidobacterium were found to be the key bacteria for ginsenoside transformation in vivo. Overall, ginseng can regulate gut microbiome diversity, further affect the synthesis of secondary metabolites, as well as promote the transformation of ginsenosides for improving the absorptivity of ginsenosides. This review can provide better insight into the interaction of ginseng with gut microbiota in multiple disorders and ginsenoside transformation.

Casual C peptide index: Predicting the subsequent need for insulin therapy in outpatients with type 2 diabetes under primary care

BACKGROUND

Evaluation of residual beta cell function is indispensable in patients with type 2 diabetes as it informs not only diagnoses but also appropriate treatment modalities. However, there is a lack of convenient biomarkers for residual beta cell function. Therefore, we evaluated endogenous insulin level as a biomarker in outpatients who were being treated with insulin therapy and in patients who were introduced to insulin therapy after 4 years.

METHODS

Data of 174 outpatients with type 2 diabetes (50% male) whose glycemia was moderately controlled (glycated A1c 7.3% [5.2%-14.8%]) were reviewed. Twenty patients whose estimated glomerular filtration rate was lower than 30 ml/min/1.73 m² were excluded from the evaluation of endogenous insulin level with both casual C-peptide index (C-CPI) and urinary C-peptide/creatinine ratio (determined at any time, generally 1-2 h after breakfast). Patients were stratified based on the provision of insulin therapy.

RESULTS

C-CPI and UCPCR were significantly lower in the insulin-treated patients than in the insulin-untreated patients (0.9 vs. 2.2, p < 0.0001; 24.7 vs. 75.5, p = 0.0003, respectively). Moreover, C-CPI were significantly lower in the insulin-requiring patients for 4 years than in the insulin-unrequiring patients (1.0 vs. 1.7, p = 0.0184). The multivariate logistic regression analysis revealed that both indicators of insulin secretion influenced the requirement for insulin therapy, but C-CPI could serve as the most convenient and useful biomarker for not only current insulin therapy requirements (p = 0.0002) but also the subsequent requirement for insulin therapy (p = 0.0008).

CONCLUSIONS

C-CPI could be determined easily, and it was found to be a more practical marker for outpatients; therefore, our findings would have critical implications for primary care.

Thiazolidinedione Derivatives: In Silico, In Vitro, In Vivo, Antioxidant and Anti-Diabetic Evaluation

This work aimed to synthesize a new antihyperglycemic thiazolidinedione based on the spectral data. The DFT\B3LYP\6-311G** level of theory was used to investigate the frontier molecular orbitals (FMOs), chemical reactivity and map the molecular electrostatic potentials (MEPs) to explain how the synthesized compounds interacted with the receptor. The molecular docking simulations into the active sites of PPAR-γ and α-amylase were performed. The in vitro potency of these compounds via α-amylase and radical scavenging were evaluated. The data revealed that compounds (4–6) have higher potency than the reference drugs. The anti-diabetic and anti-hyperlipidemic activities for thiazolidine-2,4-dione have been investigated in vivo using the alloxan-induced diabetic rat model along with the 30 days of treatment protocol. The investigated compounds didn’t show obvious reduction of blood glucose during pre-treatments compared to diabetic control, while after 30 days of treatments, the blood glucose level was lower than that of the diabetic control. Compounds (4–7) were able to regulate hyperlipidemia levels (cholesterol, triglyceride, high-density lipoproteins and low- and very-low-density lipoproteins) to nearly normal value at the 30th day.

Discovery Potent of Thiazolidinedione Derivatives as Antioxidant, α-Amylase Inhibitor, and Antidiabetic Agent

This work aimed to synthesize safe antihyperglycemic derivatives bearing thiazolidinedione fragment based on spectral data. The DFT theory discussed the frontier molecular orbitals (FMOs), chemical reactivity of compounds, and molecular electrostatic potential (MEP) to explain interaction between thiazolidinediones and the biological receptor. α-amylase is known as the initiator-hydrolysis of the of polysaccharides; therefore, developing α-amylase inhibitors can open the way for a potential diabetes mellitus drug. The molecular docking simulation was performed into the active site of PPAR-γ and α-amylase. We evaluated in vitro α-amylase's potency and radical scavenging ability. The compound 6 has the highest potency against α-amylase and radical scavenging compared to the reference drug and other members. They have been applied against anti-diabetic and anti-hyperlipidemic activity (in vivo) based on an alloxan-induced diabetic rat model during a 30-day treatment protocol. The most potent anti hyperglycemic members are 6 and 11 with reduction percentage of blood glucose level by 69.55% and 66.95%, respectively; compared with the normal control. Other members exhibited moderate to low anti-diabetic potency. All compounds showed a normal value against the tested biochemical parameters (CH, LDL, and HDL). The ADMET profile showed good oral bioavailability without any observed carcinogenesis effect.

Simultaneous Quantification of Pioglitazone and Omarigliptin in Rat Plasma by UHPLC-MS/MS and Its Application to Pharmacokinetic Study after Coadministration of the Two Drugs

Combination therapy is a common approach for clinical treatment of type 2 diabetes mellitus, especially for patients with poor monotherapy. Meta-analysis suggested that omarigliptin, a long-acting DPP-4 inhibitor, combined with pioglitazone might improve the side effects of pioglitazone. However, little is known about the pharmacokinetic properties after a coadministration. In this study, a rapid and reliable method for the simultaneous determination of the pioglitazone and omarigliptin in rat plasma by UHPLC-MS/MS was established and validated for the first time. An exsil mono C18 column (2.0 × 50 mm, 3 μm) was used to separate the analytes and the column temperature was kept at 30°C. Sitagliptin was selected as the internal standard. 0.02% formic acid aqueous solution (A) and methanol-acetonitrile (B) were used as mobile phases with gradient elution at a flow rate of 0.3 mL/min. The elution procedure was as follows: 20%B (0-0.1 min), 80%B (0.1-0.3 min), 80%B (0.3-2.0 min), and 20%B (2.1-3.0 min). A multiple reaction monitor (MRM) was used under positive ionization mode with electrospray ion source to detect pioglitazone (357.1 ⟶ 134.1), omarigliptin (399.2 ⟶ 153.0), and sitagliptin (408.2 ⟶ 235.0). The linear ranges of pioglitazone and omarigliptin were 5-2000 ng/mL and 10-4000 ng/mL, respectively. Good linear relationships were exhibited in the corresponding linear ranges (r ≥ 0.9944). The bioanalytical method was validated, and the selectivity, linearity, sensitivity, accuracy, precision, stability, recovery, and matrix effect were acceptable. The validated method was then successfully applied to pharmacokinetic study of pioglitazone combined with omarigliptin in rats. Results suggested that the combination of the two drugs had little effect on the pharmacokinetic parameters of each other in rats.

Comparison Between Pioglitazone/Metformin Combination Therapy and Sitagliptin/Metformin Combination Therapy on the Efficacy in Chinese Type 2 Diabetic Adults Insufficiently Controlled with Metformin: Study Protocol of an Open-Label, Multicenter, Non-Inferiority Parallel-Group Randomized Controlled Trial

INTRODUCTION

The prevalence of type 2 diabetes (T2D) has risen substantially in China, where its pathophysiology is primarily characterized by insulin resistance (IR). Alleviating IR may help with the management of T2D in the Chinese population. Pioglitazone and sitagliptin are two hypoglycemic medications with different pharmacological actions, both of which are optimal choices for use in combination with metformin. Previous studies have yielded mixed findings regarding the differences in hypoglycemic effects between the two agents. Though pioglitazone is associated with weight gain, both drugs have been shown to decrease visceral adipose tissue (VAT) and improve IR in individuals with T2D. There is a lack of direct comparisons between pioglitazone and sitagliptin among Chinese individuals with T2D. Therefore, this paper describes a protocol for a randomized controlled trial (RCT) that investigates the differences in hypoglycemic efficacy, IR improvement, and safety profiles between these drugs.

METHODS AND ANALYSIS

This is a 24-week, open-label, multicenter, non-inferiority parallel-group RCT with a 1:1 allocation ratio. It compares pioglitazone/metformin (15 mg/500 mg) combination therapy with sitagliptin/metformin (50 mg/500 mg) combination therapy in Chinese adults with T2D insufficiently controlled with metformin. The primary outcomes are HbA1c reduction, insulin level increase, and IR index change. The secondary outcomes are body weight and abdominal VAT decreases, lipid profiles, and inflammatory indicators. Tolerability and safety data will also be collected.

CONCLUSION

It is believed that the direct comparisons of the hypoglycemic effects, VAT reductions, and safety profiles between pioglitazone and sitagliptin will help to optimize treatments for Chinese adults with T2D who are primarily characterized by IR.

TRIAL REGISTRATION NUMBER

Chinese Clinical Trial Registry (ChiCTR1900021861).

Effects of Pioglitazone on Glucose-Dependent Insulinotropic Polypeptide-Mediated Insulin Secretion and Adipocyte Receptor Expression in Patients With Type 2 Diabetes

Incretin hormone dysregulation contributes to reduced insulin secretion and hyperglycemia in patients with type 2 diabetes mellitus (T2DM). Resistance to glucose-dependent insulinotropic polypeptide (GIP) action may occur through desensitization or downregulation of β-cell GIP receptors (GIP-R). Studies in rodents and cell lines show GIP-R expression can be regulated through peroxisome proliferator-activated receptor γ (PPARγ) response elements (PPREs). Whether this occurs in humans is unknown. To test this, we conducted a randomized, double-blind, placebo-controlled trial of pioglitazone therapy on GIP-mediated insulin secretion and adipocyte GIP-R expression in subjects with well-controlled T2DM. Insulin sensitivity improved, but the insulinotropic effect of infused GIP was unchanged following 12 weeks of pioglitazone treatment. In parallel, we observed increased GIP-R mRNA expression in subcutaneous abdominal adipocytes from subjects treated with pioglitazone. Treatment of cultured human adipocytes with troglitazone increased PPARγ binding to GIP-R PPREs. These results show PPARγ agonists regulate GIP-R expression through PPREs in human adipocytes, but suggest this mechanism is not important for regulation of the insulinotropic effect of GIP in subjects with T2DM. Because GIP has antilipolytic and lipogenic effects in adipocytes, the increased GIP-R expression may mediate accretion of fat in patients with T2DM treated with PPARγ agonists.

Neuromodulatory effects of anti-diabetes medications: A mechanistic review

Diabetes mellitus is a potent upstream event in the molecular pathophysiology which gives rise to various diabetes-related complications. There are several classes of anti-diabetic medications that have been developed to normalize blood glucose concentrations through a variety of molecular mechanisms. Beyond glucose-lowering effects, these agents may also provide further therapeutic potential. For instance, there is a high incidence of diabetes-induced neuronal disorders among patients with diabetes, who may also develop neurodegenerative and psychological complications. If anti-diabetic agents can modify the molecular mechanisms involved in the pathophysiology of neuronal comorbidities, this could potentially be translated to reducing the risk of other neurological conditions such as Alzheimer's disease, Parkinson's disease, depression, memory deficits and cognition impairments among patients with diabetes. This review aimed to shed light on some of the potentially beneficial aspects of anti-diabetic agents in lowering the risk or treating neuronal disorders by reviewing the molecular mechanisms by which these agents can potentially modulate neuronal behaviors.

[Short-term intensive combined therapy with metformin, sagliptin and dapagliflozin for newly diagnosed type 2 diabetes: efficacy, weight control and safety]

OBJECTIVE

To assess the efficacy and safety of short- term intensive hypoglycemic therapy with a triple regimen consisting of metformin, sagliptin and dapagliflozin in patients with newly diagnosed type 2 diabetes mellitus with hemoglobin Alc (HbA1c) of 9%-12%.

METHODS

We prospectively enrolled 58 patients with newly diagnosed type 2 diabetes, who were treated with metformin combined with sagliptin and dapagliflozin for 12 weeks on the basis of diabetic diet and regular exercise. Blood glucose was monitored during the treatment and the changes in HbA1c, fasting blood glucose (FBG), 2-hour postprandial blood glucose (2 hPBG), fasting insulin (FINS), 2-hour postprandial insulin (2 hPINS), fasting C-peptide (F-CP), 2-hour postprandial C-peptide (2 hP-CP), and body weight after treatment as well as the incidence of hypoglycemia and adverse events associated with the treatment were recorded.

RESULTS

Two patients withdrew from the study for intolerance of gastrointestinal reactions, and another 2 withdrew for inconvenience of access to the medicines. Fifty-four of the patients finally completed the study, including 34 male and 20 female patients. After 12 weeks of therapy, all the patients showed significant improvements in FBG, 2 hPBG, HbA1c, HOMA-beta and HOMA-IR (P < 0.001) with a mean reduction of HbA1c level by (4.19 ± 1.07)%, and the goal of HbA1c control to below 7.0% was achieved in 83.33% of the patients. The reduction of HbA1c was correlated with FBG (r=0.487, P=0.000), 2 hPBG (r=0.310, P=0.023), and HOMA-β (r=-0.398, P=0.003). The patients had a mean body weight loss by 2.47±3.38 kg (P < 0.001) and a mean decrease of body mass index (BMI) by 0.90± 1.18 kg/m2 (P < 0.001) after the therapy. The body weight-reducing effect was associated with the patients' baseline body weight (r=0.678, P=0.000), BMI (r=0.818, P=0.000), F-CP (r=0.282, P=0.039) and HOMA-IR (r=0.297, P=0.029). During the therapy 8 patients experienced hypoglycemic symptoms (10 times, 14.81%); 3 patients were diagnosed with hypoglycemia (blood glucose ≤3.9 mmol/L, 3 times), and the overall incidence of hypoglycemia was 5.56%. No serious hypoglycemia or infections of the urinary and reproductive systems occurred in these patients.

CONCLUSIONS

Short-term intensive oral hypoglycemic therapy with metformin combined with sagliptin and dapagliflozin is effective for treatment of patients with newly diagnosed type 2 diabetes with HbA1c of 9%-12% and shows a good weight-reducing effect with a low risk of hypoglycemia. The combined therapy can effectively improve β-cell insulin secretion function, and is suitable for treatment of newly diagnosed type 2 diabetic patients with high blood glucose.

Metformin and sitagliptin combination therapy ameliorates polycystic ovary syndrome with insulin resistance through upregulation of lncRNA H19

Insulin resistance (IR) is prevalent in women with polycystic ovary syndrome (PCOS). Improvement in insulin sensitivity remains one of the most effective treatment strategies for women with PCOS. This study aims to investigate the efficacy and potential mechanism of the combination therapy with metformin (DMBG) and sitagliptin (TECOS) in PCOS. To address this, insulin was used to treat rat ovarian granulosa cells to establish the cellular PCOS model. Insulin and human chorionic gonadotropin (HCG) were subcutaneously injected into SD rats to establish a rat model of hyperandrogenism with pathogenesis similar to PCOS. Our results showed that co-treatment with TECOS and DMBG attenuated the induced apoptosis and insulin resistance (IR) in PCOS model cells, and improved reproductive hormone disorders, ovarian polycystic changes, and IR of PCOS rats. Mechanistically, upregulation of H19 by H19-expressing lentiviruses enhanced efficacy of combination therapy. Furthermore, co-treatment with TECOS and DMBG induced H19 expression via suppressing the PI3K/AKT-DNMT1 pathway. Collectively, these findings demonstrate that combination treatment with TECOS and DMBG ameliorates PCOS with IR, at least partially, through upregulation of lncRNA H19.

Reduced expression of microRNA-199a-3p is associated with vascular endothelial cell injury induced by type 2 diabetes mellitus

The aim of the present study was to investigate the function and mechanism of action of microRNA (miRNA or miR)-199a-3p in vascular endothelial cell injury induced by type 2 diabetes mellitus (T2DM). A total of 36 patients with T2DM (26 males and 10 females; mean age, 52.5±7.0 years) and 20 healthy subjects (10 males and 10 females; mean age, 55.6±4.5 years) were included in the present study. Peripheral blood samples were obtained from all participants and total RNA was extracted Reverse transcription-quantitative polymerase chain reaction was performed to determine the expression of miR-199a-3p. Following the transfection of human umbilical vein endothelial cells (HUVECs) with a negative control (NC) miRNA or miR-199a-3p mimics, cell proliferation was assessed using a Cell Counting kit-8 assay. Cell migration was investigated using Transwell assays and flow cytometry was performed to detect the apoptosis of HUVECs. HUVECs were infected with Ad-GFP-LC3B and laser-scanning confocal microscopy was performed to observe autophagosomes in HUVECs. Western blotting was used to measure the expression of proteins associated with autophagy and the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT)/nuclear factor (NF)-κB signaling pathway. MiR-199a-3p was downregulated in peripheral blood from patients with T2DM compared with healthy subjects. Transfection with miR-199a-3p mimics promoted the proliferation and migration of HUVECs. However, miR-199a-3p overexpression inhibited the apoptosis of HUVECs. MiR-199a-3p facilitated HUVEC autophagy by affecting autophagy-associated signaling pathways. Furthermore, miR-199a-3p regulated the biological functions of HUVECs via the PI3K/AKT/NF-κB signaling pathway. The results of the present study suggest that miR-199a-3p expression was reduced in patients with T2DM compared with healthy subjects and may be associated with vascular endothelial cell injury. In addition, miR-199a-3p promoted the proliferation, migration and autophagy of HUVECs, potentially by regulating the PI3K/AKT/NF-κB signaling pathway. Therefore, miR-199a-3p may function as protector of vascular endothelia.

Practical strategies for improving outcomes in T2DM: The potential role of pioglitazone and DPP4 inhibitors

T2DM is a complex disease underlined by multiple pathogenic defects responsible for the development and progression of hyperglycaemia. Each of these factors can now be tackled in a more targeted manner thanks to glucose-lowering drugs that have been made available in the past 2 to 3 decades. Recognition of the multiplicity of the mechanisms underlying hyperglycaemia calls for treatments that address more than 1 of these mechanisms, with more emphasis placed on the earlier use of combination therapies. Although chronic hyperglycaemia contributes to and amplifies cardiovascular risk, several trials have failed to show a marked effect from intensive glycaemic control. During the past 10 years, the effect of specific glucose-lowering agents on cardiovascular risk has been explored with dedicated trials. Overall, the cardiovascular safety of the new glucose-lowering agents has been proven with some of the trials summarized in this review, showing significant reduction of cardiovascular risk. Against this background, pioglitazone, in addition to exerting a sustained glucose-lowering effect, also has ancillary metabolic actions of potential interest in addressing the cardiovascular risk of T2DM, such as preservation of beta-cell mass and function. As such, it seems a logical agent to combine with other oral anti-hyperglycaemic agents, including dipeptidyl peptidase-4 inhibitors (DPP4i). DPP4i, which may also have a potential to preserve beta-cell function, is available as a fixed-dose combination with pioglitazone, and could, potentially, attenuate some of the side effects of pioglitazone, particularly if a lower dose of the thiazolidinedione is used. This review critically discusses the potential for early combination of pioglitazone and DPP4i.