Method for evaluating the human bioequivalence of acarbose based on pharmacodynamic parameters

43 G > T polymorphism in the sucrase-isomaltase gene in the Chinese population prevents the glucose-lowering effect of acarbose

BACKGROUND

Acarbose is an α-glucosidase inhibitor widely used clinically for its significant hypoglycemic effect, albeit with inter-individual variations in response. The sucrase-isomaltase (SI) enzyme is the primary target of acarbose. This study aims to investigate the impact of genetic polymorphisms in the SI gene on the pharmacodynamics of acarbose.

METHODS

The Illumina sequencing platform and variation-related databases were employed to analyze probable gene polymorphism sites of SI. Based on the SI polymorphism sites, Chinese subjects (n = 66) were categorized into the wild-type homozygous group (Group A) and the heterozygous variant group (Group B, SI 43 G > T). The validated hexokinase method was utilized to determine glucose concentrations in participants' serum samples. The differences in blood glucose concentration reduction and pharmacodynamic parameters peak concentration (Cmax) and area under the curve (AUC0-2h) after administering the same dose of acarbose were analyzed between the two groups of subjects.

RESULTS

Our results showed that the mean changes in glucose Cmax, AUC0-2h, maximum increase, and maximum decrease in Group B were each lower by 67.66 %, 63.05 %, 53.17 %, and 50 % compared to Group A (all p < 0.05).

CONCLUSIONS

These data suggested that genetic polymorphism of the SI gene can significantly influence the hypoglycemic efficacy of acarbose, and the polymorphism of SI is associated with individual differences in clinical treatment outcomes.

The Anti-Diabetic Effects of Medicinal Plants Belonging to the Liliaceae Family: Potential Alpha Glucosidase Inhibitors

Background

Diabetes mellitus is a complex metabolic disorder that has an enormous impact on people's quality of life and health. Although there is no doubt about the effectiveness of oral hypoglycemic agents combined with lifestyle management in controlling diabetes, no individual has ever been reported to have been completely cured of the disease. Globally, many medicinal plants have been used for the management of diabetes in various traditional systems of medicine. A deep look in the literature has revealed that the Liliaceae family have been poorly investigated for their antidiabetic activity and phytochemical studies. In this review, we summarize medicinal plants of Liliaceae utilized in the management of type II diabetes mellitus (T2DM) by inhibition of α-glucosidase enzyme and phytochemical content.

Methods

The literature search was conducted using databases including PubMed, ScienceDirect, and Google Scholar to find the significant published articles about Liliaceae plants utilized in the prevention and treatment of antidiabetics. Data were filtered to the publication period from 2013 to 2023, free full text and only English articles were included. The keywords were Liliaceae OR Alliaceae OR Amaryllidaceae AND Antidiabetic OR α-glucosidase.

Results

Six medicinal plants such as Allium ascalonicum, Allium cepa, Allium sativum, Aloe ferox, Anemarrhena asphodeloides, and Eremurus himalaicus are summarized. Phytochemical and α-glucosidase enzymes inhibition by in vitro, in vivo, and human studies are reported.

Conclusion

Plants of Liliaceae are potential as medicine herbs to regulating PPHG and prevent the progression of T2DM and its complication. In silico study, clinical application, and toxicity evaluation are needed to be investigated in the future.

Sample Size Determination and Study Design Impact on Dose-Scale Pharmacodynamic Bioequivalence: a Case Study Using Orlistat

Dose-scale pharmacodynamic bioequivalence is recommended for evaluating the consistency of generic and innovator formulations of certain locally acting drugs, such as orlistat. This study aimed to investigate the standard methodology for sample size determination and the impact of study design on dose-scale pharmacodynamic bioequivalence using orlistat as the model drug. A population pharmacodynamic model of orlistat was developed using NONMEM 7.5.1 and utilized for subsequent simulations. Three different study designs were evaluated across various predefined relative bioavailability ratios of test/reference (T/R) formulations. These designs included Study Design 1 (2×1 crossover with T1 60 mg, R1 60 mg, and R2 120 mg), Study Design 2 (2×1 crossover with T2 120 mg, R1 60 mg, and R2 120 mg), and Study Design 3 (2×2 crossover with T1 60 mg, T2 120 mg, R1 60 mg, and R2 120 mg). Sample sizes were determined using a stochastic simulation and estimation approach. Under the same T/R ratio and power, Study Design 3 required the minimum sample size for bioequivalence, followed by Study Design 1, while Study Design 2 performed the worst. For Study Designs 1 and 3, a larger sample size was needed on the T/R ratio < 1.0 side for the same power compared to that on the T/R ratio > 1.0 side. The opposite asymmetry was observed for Study Design 2. We demonstrated that Study Design 3 is most effective for reducing the sample size for orlistat bioequivalence studies, and the impact of T/R ratio on sample size shows asymmetry.

Predictors of acarbose therapeutic efficacy in newly diagnosed type 2 diabetes mellitus patients in China

Background

Acarbose is one of the optimal drugs for patients with the first diagnosis of type 2 diabetes mellitus (T2DM). But what kind of emerging patients has the best therapeutic response to acarbose therapy has never been reported. To this end, we investigated predictors of acarbose therapeutic efficacy in newly diagnosed T2DM patients in China.

Methods

A total of 346 T2DM patients received acarbose monotherapy for 48 weeks as part of participating in the Study of Acarbose in Newly Diagnosed Patients with T2DM in China (MARCH study) from November 2008 to June 2011. Change in glycated hemoglobin (ΔHbA1c) served as a dependent variable while different baseline variables including sex, age, disease duration, weight, body mass index (BMI), systolic blood pressure (SBP), diastolic blood pressure (DBP), HbA1c, fasting plasma glucose (FPG), 2-h postprandial blood glucose (2 h PG), fasting insulin (FINS), 2-h postprandial insulin (2 h INS), early insulin secretion index (IGI), homeostasis model assessment of insulin resistance index (HOMA-IR), homeostasis model assessment of beta cell function (HOMA-B), area under the curve (AUC) of glucagon, insulin and GLP-1 were assessed as independent predictors. Step-wise multiple linear regression was employed for statistical analysis.

Results

The results suggested that independent predictors of ΔHbA1c at 12 weeks included baseline body weight (β = − 0.012, P = 0.006), DBP (β = 0.010, P = 0.047), FPG (β = 0.111, P = 0.005) and 2 h PG (β = 0.042, P = 0.043). Independent predictors of ΔHbA1c at 24 weeks included disease duration (β = 0.040, P = 0.019) and FPG (β = 0.117, P = 0.001). Finally, independent predictor of ΔHbA1c at 48 weeks was disease duration (β = 0.038, P = 0.046).

Conclusions

Acarbose may be more effective in newly diagnosed T2DM patients with low FPG, low 2 h PG and obesity. The earlier T2DM is diagnosed and continuously treated with acarbose, the better the response to therapy.