Acarbose actions on insulin resistance and inflammatory parameters during an oral fat load

A systematic review, meta-analysis, dose-response, and meta-regression of the effects of acarbose intake on glycemic markers in adults

Purpose

Prior research has yielded mixed results regarding the impact of acarbose intake on glycemic markers. To provide a more comprehensive analysis, a systematic review and meta-analysis was performed to compile data from various randomized controlled trials (RCTs) examining the effects of acarbose intake on fasting blood sugar (FBS), insulin, hemoglobin A1C (HbA1c), and homeostasis model assessment of insulin resistance (HOMA-IR) in adults.

Methods

To identify relevant literature up to April 2023, a comprehensive search was conducted on various scholarly databases, including PubMed, Web of Science, and Scopus databases. The effect size of the studies was evaluated using a random-effects model to calculate the weighted mean differences (WMD) and 95% confidence intervals (CI). Heterogeneity between studies was assessed using Cochran's Q test and I2.

Results

This systematic review and meta-analysis included a total of 101 RCTs with a total of 107 effect sizes. The effect sizes for FBS in milligrams per deciliter (mg/dl), insulin in picomoles per liter (pmol/l), hemoglobin A1C (HbA1c) in percentage (%), and homeostasis model assessment of insulin resistance (HOMA-IR) were 92, 46, 80, and 22, respectively. The pooled analysis indicated that acarbose intake resulted in significant decreases in FBS (p = 0.018), insulin (p < 0.001), HbA1c (p < 0.001), and HOMA-IR (p < 0.001).

Conclusion

The findings of this systematic review and meta-analysis suggest that acarbose intake can potentially lead to significant improvements in glycemic parameters by decreasing the levels of FBS, HbA1c, and insulin. However, larger and more rigorously designed studies are still needed to further evaluate and strengthen this association.

The effect of acarbose on inflammatory cytokines and adipokines in adults: a systematic review and meta-analysis of randomized clinical trials

BACKGROUND

Although a large number of trials have observed an anti-inflammatory property of acarbose, the currently available research remains controversial regarding its beneficial health effects. Hence, the purpose of this study was to examine the effect of acarbose on inflammatory cytokines and adipokines in adults.

METHODS

PubMed, Web of Science, and Scopus were systematically searched until April 2023 using relevant keywords. The mean difference (MD) of any effect was calculated using a random-effects model. Weighted mean difference (WMD) and 95% confidence intervals (CIs) were calculated via the random-effects model.

RESULTS

The current meta-analysis of data comprised a total of 19 RCTs. Meta-analysis showed that acarbose significantly decreased tumor necrosis factor-alpha (TNF-α) (weighted mean difference [WMD]) = - 4.16 pg/ml, 95% confidence interval (CI) - 6.58, - 1.74; P = 0.001) while increasing adiponectin (WMD = 0.79 ng/ml, 95% CI 0.02, 1.55; P = 0.044). However, the effects of acarbose on TNF-α concentrations were observed in studies with intervention doses ≥ 300 mg/d (WMD = - 4.09; 95% CI - 7.00, - 1.18; P = 0.006), and the adiponectin concentrations were significantly higher (WMD = 1.03 ng/ml, 95%CI 0.19, 1.87; P = 0.016) in studies in which the duration of intervention was less than 24 weeks. No significant effect was seen for C-reactive protein (CRP; P = 0.134), interleukin-6 (IL-6; P = 0.204), and leptin (P = 0.576).

CONCLUSION

Acarbose had beneficial effects on reducing inflammation and increasing adiponectin. In this way, it may prevent the development of chronic diseases related to inflammation. However, more studies are needed.

The effect of acarbose on lipid profiles in adults: a systematic review and meta-analysis of randomized clinical trials

PURPOSE

Dyslipidemia, characterized by elevated levels of triglycerides (TG), low-density lipoprotein (LDL), total cholesterol (TC), and reduced levels of high-density lipoprotein (HDL), is a major risk factor for cardiovascular diseases (CVD). Several studies have shown the potential of acarbose in improving serum lipid markers. However, there have been conflicting results on the topic in adults. Therefore, a comprehensive systematic review and meta-analysis was conducted to assess the impact of acarbose on lipid profiles.

METHODS

The random-effects approach was used to combine the data, and the results were provided as weighted mean difference (WMD) with 95% confidence intervals (CI).

RESULTS

Our meta-analysis included a total of 74 studies with a combined sample size of 7046 participants. The results of the analysis showed that acarbose resulted in a reduction in levels of TG (WMD = - 13.43 mg/dl, 95% CI: - 19.20, - 7.67; P < 0.001) and TC (WMD = - 1.93 mg/dl, 95% CI: - 3.71, - 0.15; P = 0.033), but did not affect other lipid markers. When conducting a nonlinear dose-response analysis, we found that acarbose was associated with an increase in levels of HDL (coefficients = 0.50, P = 0.012), with the highest increase observed at a dosage of 400 mg/d. Furthermore, our findings suggested a non-linear relationship between the duration of the intervention and TC (coefficients = - 18.00, P = 0.032), with a decline observed after 50 weeks of treatment.

CONCLUSION

The findings of this study suggest that acarbose can reduce serum levels of TG and TC. However, no significant effects were observed on LDL or HDL levels.

The effects of acarbose treatment on cardiovascular risk factors in impaired glucose tolerance and diabetic patients: a systematic review and dose-response meta-analysis of randomized clinical trials

Acarbose (ACB) seems to be an effective drug in the management of cardiovascular risk factors. However, no previous meta-analysis of randomized controlled trials (RCTs) has been done to evaluate the effects of ACB on cardiovascular risk factors on impaired glucose tolerance (IGT), type 2 diabetes mellitus (T2D), and type 1 diabetes mellitus (T1D). We comprehensively searched electronic databases including Scopus, Web of Science, and PubMed for RCTs for related keywords up to September 2022. A random-effects model was used to estimate the weighted mean difference (WMD) and 95% confidence interval (CI). The pooled analysis demonstrated that ACB treatment had a significant effect on fasting blood glucose (FBG) (WMD = -3.55 mg/dL; 95%CI: -6.29, -0.81; p = 0.011), fasting insulin (WMD = -6.73 pmoL/L; 95%CI: -10.37, -3.10; p < 0.001), HbA1c [WMD = -0.32%; 95%CI: -0.45, -0.20; p < 0.001], body weight (WMD = -1.25 kg; 95%CI: -1.79, -0.75; p < 0.001), body mass index (BMI) (WMD = -0.64 kg/m2; 95%CI: -0.92, -0.37; p < 0.001), tumor necrosis factor-alpha (TNF-α) (WMD = -2.70 pg/mL, 95%CI: -5.25, -0.16; p = 0.037), leptin (WMD = -1.58 ng/mL; 95%CI: -2.82, -0.35; p = 0.012), alanine transaminase (ALT) (WMD = 0.71 U/L; 95%CI: -0.31, 1.85; p = 0.164), triglyceride (TG) (WMD = -13.89 mg/dL; 95%CI: -20.69, -7.09; p < 0.001), total cholesterol (TC) (WMD = -2.26 mg/dL; 95%CI: -4.18, -0.34; p = 0.021), systolic blood pressure (SBP) (WMD = -1.29 mmHg; 95%CI: -2.44, -0.15; p = 0.027), and diastolic blood pressure (DBP) (WMD = 0.02 mmHg; 95%CI: -0.41, 0.45; p = 0.925) in an intervention group, compared with a placebo group. The non-linear dose-response analysis showed that ACB reduces the TC in trial duration by >50 weeks, and 180 mg/day is more effective for the decrement of CRP. ACB can improve lipid profiles, glycemic indices, anthropometric indices, and inflammatory markers in T2D, T1D, and IGT patients.

Sex differences in neuroimmunoendocrine communication. Involvement on longevity

Endocrine, nervous, and immune systems work coordinately to maintain the global homeostasis of the organism. They show sex differences in their functions that, in turn, contribute to sex differences beyond reproductive function. Females display a better control of the energetic metabolism and improved neuroprotection and have more antioxidant defenses and a better inflammatory status than males, which is associated with a more robust immune response than that of males. These differences are present from the early stages of life, being more relevant in adulthood and influencing the aging trajectory in each sex and may contribute to the different life lifespan between sexes.

Acarbose Protects Glucolipotoxicity-Induced Diabetic Nephropathy by Inhibiting Ras Expression in High-Fat Diet-Fed db/db Mice

Diabetic nephropathy (DN) exacerbates renal tissue damage and is a major cause of end-stage renal disease. Reactive oxygen species play a vital role in hyperglycemia-induced renal injury. This study examined whether the oral hypoglycemic drug acarbose (Ab) could attenuate the progression of DN in type 2 diabetes mellitus mice. In this study, 50 mg/kg body weight of Ab was administered to high-fat diet (HFD)-fed db/db mice. Their body weight was recorded every week, and the serum glucose concentration was monitored every 2 weeks. Following their euthanasia, the kidneys of mice were analyzed through hematoxylin and eosin, periodic acid Schiff, Masson's trichrome, and immunohistochemistry (IHC) staining. The results revealed that Ab stabilized the plasma glucose and indirectly improved the insulin sensitivity and renal functional biomarkers in diabetic mice. In addition, diabetes-induced glomerular hypertrophy, the saccharide accumulation, and formation of collagen fiber were reduced in diabetic mice receiving Ab. Although the dosages of Ab cannot decrease the blood sugar in db/db mice, our results indicate that Ab alleviates glucolipotoxicity-induced DN by inhibiting kidney fibrosis-related proteins through the Ras/ERK pathway.

Diabetes medications as potential calorie restriction mimetics-a focus on the alpha-glucosidase inhibitor acarbose

The field of aging research has grown rapidly over the last half-century, with advancement of scientific technologies to interrogate mechanisms underlying the benefit of life-extending interventions like calorie restriction (CR). Coincident with this increase in knowledge has been the rise of obesity and type 2 diabetes (T2D), both associated with increased morbidity and mortality. Given the difficulty in practicing long-term CR, a search for compounds (CR mimetics) which could recapitulate the health and longevity benefits without requiring food intake reductions was proposed. Alpha-glucosidase inhibitors (AGIs) are compounds that function predominantly within the gastrointestinal tract to inhibit α-glucosidase and α-amylase enzymatic digestion of complex carbohydrates, delaying and decreasing monosaccharide uptake from the gut in the treatment of T2D. Acarbose, an AGI, has been shown in pre-clinical models to increase lifespan (greater longevity benefits in males), with decreased body weight gain independent of calorie intake reduction. The CR mimetic benefits of acarbose are further supported by clinical findings beyond T2D including the risk for other age-related diseases (e.g., cancer, cardiovascular). Open questions remain regarding the exclusivity of acarbose relative to other AGIs, potential off-target effects, and combination with other therapies for healthy aging and longevity extension. Given the promising results in pre-clinical models (even in the absence of T2D), a unique mechanism of action and multiple age-related reduced disease risks that have been reported with acarbose, support for clinical trials with acarbose focusing on aging-related outcomes and incorporating biological sex, age at treatment initiation, and T2D-dependence within the design is warranted.

Why do sexes differ in lifespan extension? Sex-specific pathways of aging and underlying mechanisms for dimorphic responses

Males and females typically have different lifespans and frequently differ in their responses to anti-aging interventions. These sex-specific responses are documented in mice and Drosophila species, in addition to other organisms where interventions have been tested. While the prevalence of sex-specific responses to anti-aging interventions is now recognised, the underlying causes remain poorly understood. This review first summarises the main pathways and interventions that lead to sex-specific lifespan responses, including the growth-hormone/insulin-like growth factor 1 (GH-IGF1) axis, mechanistic target of rapamycin (mTOR) signalling, and nutritional and pharmacological interventions. After summarising current evidence, several different potential causes for sex-specific responses are discussed. These include sex-differences in xenobiotic metabolism, differing disease susceptibility, sex-specific hormone production and chromosomes, and the relative importance of different signalling pathways in the control of male and female life-history. Understanding why sex-differences in lifespan-extension occur should provide a greater understanding of the mechanisms that regulate the aging process in each sex, and will be crucial for understanding the full implications of these treatments if they are translated to humans.

Protective effects of acarbose against insulitis in multiple low-dose streptozotocin-induced diabetic mice

AIMS

The development of type 1 diabetes is associated with inflammatory lesion of the pancreatic islets, known as insulitis. In this study, we focused on the protective effects of acarbose against insulitis in streptozotocin (STZ)-induced diabetic mice and the underlying mechanisms.

MAIN METHODS

The mouse models were established via intraperitoneal injection of multiple low-dose STZ. Blood glucose level and body weight were measured. The severity of insulitis and inflammatory parameters in pancreatic tissues were evaluated. Insulin levels in pancreas and serum were also assessed. In vitro, MIN6 β cells were exposed to pro-inflammatory cytokines to assess the protective effects of acarbose. Cell function and apoptosis were evaluated.

KEY FINDINGS

We found that acarbose administration by gavage reduced the severity of insulitis and improved insulin levels in the experimental diabetic mice. ELISA revealed decreased levels of the inflammatory response markers IL-1β and TNF-α in mouse pancreatic tissues following acarbose treatment. In vitro, acarbose increased cell viability, decreased cell apoptosis, and improved GSIS in MIN6 β cells exposed to pro-inflammatory cytokines. In addition, caspase-3 level and p-p53/p53 ratio in β cells were reduced by acarbose treatment.

SIGNIFICANCE

Taken together, these results revealed a novel function of acarbose in attenuating insulitis. The protective effects of acarbose elicited in vitro and in vivo were shown to be mediated, at least in part, through its anti-inflammatory action.

Evaluation of the Effects of Acarbose on Weight and Metabolic, Inflammatory, and Cardiovascular Markers in Patients with Obesity and Overweight

Background:

Metabolic syndrome (MetS) refers to a cluster of risk factors for cardiovascular disease and type 2 diabetes. The aim of this study is to assess the effects of acarbose as an antihyperglycemic agent (drug) on late complications of MetS.

Methods:

This double-blind randomized clinical trial was done on patients with MetS admitted to Isfahan Endocrine and Metabolism Research Center. They were assigned randomly to two groups: A who received acarbose (n = 32) and group B who received a placebo (n = 42) for 6 months. Cardiovascular indexes including flow-mediated dilation (FMD), intima-media thickness (IMT), epicardial fat thickness (EFT), and C-reactive protein (CRP) were measured at baseline and 6 months after the treatment and compared between the two groups.

Results:

Post-intervention mean of weight (mean difference: −2.5 ± 0.89) and abdominal obesity (mean difference: −2.2 ± 0.64) in acarbose group were significantly decreased (P value < 0.001). High-density lipoprotein (HDL) level in acarbose group was significantly higher than control group (44.7 ± 7.6 vs 41.1 ± 6.4; P value = 0.043), while the other metabolic parameters were not significantly different between the two groups (P value > 0.05). In both groups, CRP and EFT decreased significantly after the intervention, and the levels of CRP, EFT, and IMT markers in the acarbose group were significantly lower than control group (P value < 0.05).

Conclusions:

The administration of acarbose in patients with MetS can decrease weight and abdominal obesity as well as the reduction of inflammatory and cardiovascular markers, including CRP, EFT, and IMT and also increases HDL.

Modulation of inflammatory pathways, medicinal uses and toxicities of Uvaria species: potential role in the prevention and treatment of inflammation

The therapeutic efficacy of the contemporary anti-inflammatory drugs are well established; however, prolonged use of such can often lead to serious and life-threatening side effects. Natural product-based anti-inflammatory compounds with superior efficacy and minimum toxicity can serve as possible therapeutic alternatives in this scenario. Genus Uvaria is a part of Annonaceae family, while the majority of its species are widely distributed in tropical rain forest regions of South East Asia. Uvaria species have been used extensively used as traditional medicine for treating all sorts of inflammatory diseases including catarrhal inflammation, rheumatism, acute allergic reactions, hemorrhoids, inflammatory liver disease and inflamed joints. Phytochemical analysis of Uvaria species has revealed flavones, flavonoids, tannins, saponins, polyoxygenated cyclohexene and phenolic compounds as major phyto-constituents. This review is an attempt to highlight the anti-inflammatory activity of Uvaria species by conducting a critical appraisal of the published literature. The ethnopharmacological relevance of Uvaria species in the light of toxicological studies is also discussed herein. An extensive and relevant literature on anti-inflammatory activity of Uvaria species was collected from available books, journals and electronic databases including PubMed, ScienceDirect, Scopus, Proquest and Ovid. Extracts and isolates of Uvaria species exhibited significant anti-inflammatory activity through various mechanisms of action. 6,7-di-O-Methyl-baicalein, flexuvarol B, chrysin, (-)-zeylenol, 6-hydroxy-5,7-dimethoxy-flavone, and pinocembrin were the most potent anti-inflammatory compounds with comparable IC₅₀ with positive controls. Therefore, it is suggested that further research should be carried out to determine the pharmacokinetics, pharmacodynamics and toxicity of these therapeutically significant compounds, to convert the pre-clinical results into clinical data for drug development and design.

Combination Therapy of Acarbose and Cyclosporine a Ameliorates Imiquimod-Induced Psoriasis-Like Dermatitis in Mice

Moderate to severe psoriasis, an immune-mediated inflammatory disease, adversely affects patients' lives. Cyclosporin A (CsA), an effective immunomodulator, is used to treat psoriasis. CsA is ineffective at low doses and toxic at high doses. Acarbose (Acar), a common antidiabetic drug with anti-inflammatory and immunomodulatory effects, reduces imiquimod (IMQ)-induced psoriasis severity. Combinations of systemic drugs are generally more efficacious and safer than higher doses of single drugs. We observed that mice treated with a combination of Acar (250 mg/kg) and low-dose CsA (10 or 20 mg/kg) exhibited significantly milder IMQ-induced psoriasis-like dermatitis and smoother back skin than those treated with Acar (250 mg/kg), low-dose CsA (10 or 20 mg/kg), or IMQ alone. The combination therapy significantly reduced serum and skin levels of Th17-related cytokines (interleukin (IL)-17A, IL-22, and IL-23) and the Th1-related cytokine tumor necrosis factor-α (TNF-α) compared with Acar, low-dose CsA, and IMQ alone. Additionally, the combination therapy significantly reduced the percentages of IL-17- and IL-22-producing CD4⁺ T-cells (Th17 and Th22 cells, respectively) and increased that of Treg cells. Our data suggested that Acar and low-dose CsA in combination alleviates psoriatic skin lesions by inhibiting inflammation. The findings provide new insights into the effects of immunomodulatory drugs in psoriasis treatment.

Alpha-Glucosidase Inhibitors Alter Gut Microbiota and Ameliorate Collagen-Induced Arthritis

Acarose is an anti-diabetic drug and exhibits anti-arthritic effects. We hypothesized that acarbose influences the gut microbiota to affect the course of arthritis and tested this hypothesis in a collagen-induced arthritis (CIA) murine model. Acarbose in drinking water was administered via gastric gavage started prior to or at the time of CIA induction. Gut microbiota were evaluated with 16S rRNA gene sequencing from fecal pellets collected prior to arthritis induction, during onset of arthritis, and after treatment. Immune response was evaluated by measuring changes in T helper-17 (Th17) and T regulatory (Treg) cells in the spleen and intestine, as well as serum cytokine levels. Before induction of CIA, acarbose significantly reduced the incidence of arthritis and attenuated clinical severity of arthritis. The frequency of Th17 cells was significantly decreased in the intestinal lamina propria in acarbose treated mice. Mice that were treated with acarbose showed significantly increased CD4+CD25+Foxp3+ Treg cells with elevation of Helios and CCR6. A remarkable alteration in microbial community was observed in acarbose treated mice. Bacterial diversity and richness in mice with arthritis were significantly lower than those in acarbose treated groups. The frequency of Firmicutes was significantly reduced after arthritis onset but was restored after treatment with acarbose. The frequency of Lactobacillus, Anaeroplasma, Adlercreutzia, RF39 and Corynebacterium was significantly higher in control groups than in acarbose treated, while Oscillospira, Desulfovibrio and Ruminococcus enriched in acarbose treated group. Miglitol, another α-glucosidase inhibitor showed a similar but less potent anti-arthritic effect to that of acarbose. These data demonstrate that acarbose alleviated CIA through regulation of Th17/Treg cells in the intestinal mucosal immunity, which may have resulted from the impact of acarbose on gut microbial community. Inexpensive antidiabetic drugs with an excellent safety profile are potentially useful for managing rheumatoid arthritis.

Protective effects of acarbose against vascular endothelial dysfunction through inhibiting Nox4/NLRP3 inflammasome pathway in diabetic rats

The cardiovascular efficacy of glucose-lowering drugs is needed due to the cardiovascular complication in type 2 diabetes mellitus (T2DM). Acarbose is an α-glucosidase inhibitor that suppresses postprandial hyperglycemia, however, the cardiovascular protection of acarbose has still remained controversial. NLRP3 inflammasome activation mediated tight junction disruption, a hallmark event of endothelial barrier dysfunction leading to endothelial hyperpermeability in diabetes. Given the anti-inflammatory property of acarbose, it was investigated that acarbose protected against vascular endothelial barrier dysfunction through inhibiting NLRP3 inflammasome in vascular endothelial cells in T2DM rats. The rat aortic endothelial cells (RAECs) were incubated with high glucose (HG, 30 mM) for 24 h in vitro. It was found that HG significantly induced the formation and activation of NLRP3 inflammasome, which was markedly blocked by acarbose treatment. Furthermore, acarbose blocked the Nox4-dependent superoxide (O₂^.-) generation, which regulated NLRP3 inflammasome in RAECs. Importantly, we found that acarbose remarkably enhanced the junction protein expression of ZO-1 and VE-Cadherin and consequently abolished vascular hyperpermeability, which was associated with inhibiting NLRP3 inflammasome in RAECs. In vivo, acarbose intervention relieved vascular leakage in the heart of diabetic rats injected with Evans blue dye and the vasodilatory response to acetylcholine, which was accompanied with the restoration of ZO-1, VE-Cadherin, Nox4 and NLRP3 inflammasome in the aortal endothelium of diabetic rats. Taken together, our data indicated that acarbose ameliorated endothelial barrier dysfunction by directly inhibiting NLRP3 inflammasome which was dependent on inhibiting Nox4 oxidase-dependent O₂^.- production. These properties might carry a potential significance for acarbose in cardiovascular protection in diabetic patients.

Effects of acarbose and metformin on the inflammatory state in newly diagnosed type 2 diabetes patients: a one-year randomized clinical study

OBJECTIVE

This study aimed to investigate the changes in inflammatory biomarkers between newly diagnosed type 2 diabetes (T2DM) patients under one-year acarbose treatments and those under metformin managements.

METHODS

Seventy patients with newly diagnosed T2DM and 32 volunteers with normal glucose tolerance (normal controls, NCs) were enrolled. Seventy patients with T2DM were randomly assigned to two subgroups and treated with acarbose (n=34) or metformin (n=36) for 1 year. Blood glucose, insulin, glycosylated hemoglobin (A1C), triglyceride (TG), total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), and inflammatory biomarker levels (interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), interleukin-2 (IL-2), and ferritin) were detected at 0, 6 and 12 months.

RESULTS

After adjusting for sex, the waist-to-hip ratio (WHR) and body mass index (BMI), higher fasting plasma glucose (FPG), standard meal test 1/2 hr and 2 hr glucose, TG, TC, LDL-C, IL-6, TNF-α, IL-2 and ferritin levels were observed in T2DM group than in NCs (P<0.05). After 6 months of treatment, TNF-α levels were significantly decreased in both subgroups, and IL-6 and ferritin levels were significantly decreased after 12 months (P<0.05). However, no significant differences in the IL-6, TNF-α and ferritin levels were observed between the two subgroups. Moreover, significantly higher IL-6 and TNF-α levels were detected in the T2DM group than in NCs after 12 months of treatment (P<0.05).

CONCLUSION

Patients with newly diagnosed T2DM exhibited a marked chronic inflammatory state characterized by increased IL-6, TNF-α, IL-1β, IL-2 and ferritin levels. After 1 year of treatment with acarbose or metformin, IL-6, TNF-α, IL-1β and ferritin levels were significantly decreased compared with the baseline. The anti-inflammatory effects of acarbose and metformin were comparable and required a long-term treatment (1 year), but the characteristics were different. Further investigations are needed to determine whether this effect was independent of the hypoglycemic effects.

Anti-inflammatory properties of antidiabetic agents

The reciprocal relationship between hyperglycemia and inflammation in the setting of diabetes mellitus has been the subject of extensive research. Insulin resistance, the hallmark of diabetic metabolic dysregulation, has been linked to the inflammatory cascade occurring mainly in adipose tissue. The main pathophysiologic processes facilitating the aforementioned interplay, is a phenotype switch of macrophages to the M1 class following gluco- and lipotoxicity and gut microbial remodeling. Given the correlation between inflammation and metabolic abnormalities, the elucidation of the exact mechanisms linking the two along with exploring the possible role of modulation of one in order to alter the other, could open up the possibility of novel therapeutic approaches for diabetes mellitus and its complications. Therefore, the aim of this review is to summarize the growing body of evidence concerning the molecular basis and results of pro-inflammatory processes in diabetic subjects along with the effect of current antidiabetic treatment options on tissue inflammation.

A review of the anti-inflammatory properties of antidiabetic agents providing protective effects against vascular complications in diabetes

The global prevalence of Type 2 diabetes mellitus and its associated complications are growing rapidly. Although the role of hyperglycemia is well recognized in the pathophysiology of diabetic complications, its exact underlying mechanisms are not fully understood. In this regard, accumulating evidence suggests that the role of inflammation appears pivotal, with studies showing that most diabetic complications are associated with an inflammatory response. Several classes of antidiabetic agents have been introduced for controlling glycemia, with evidence that these pharmacological agents may have modulatory effects on inflammation beyond their glucose-lowering activity. Here we review the latest evidence on the anti-inflammatory effects of commonly used antidiabetic medications and discuss the relevance of these effects on preventing diabetic complications.

Alpha-glucosidase inhibitors and risk of cancer in patients with diabetes mellitus: a systematic review and meta-analysis

Several studies have shown that anti-diabetic medications may modify the risk of cancer. We performed a systematic review and meta-analysis to evaluate the effect of alpha-glucosidase inhibitors (AGIs) on the risk of cancer in patients with diabetes mellitus. We conducted a systematic search of Medline, EMBASE, and Web of Science databases, up to September 30, 2016. Random-effects model was used to estimate the summary odds ratios (ORs) with 95% CI. Twenty-five studies (14 cohort, 7 case-control, and 4 randomized controlled trials) involving 1,285,433 patients with diabetes were included. Meta-analysis of observational studies showed that the use of AGIs was associated with a lower risk of developing cancer (OR = 0.86, 95% CI 0.78-0.96), especially gastrointestinal cancer (OR = 0.83, 95% CI 0.71-0.97). There was considerable heterogeneity across the studies introduced partly by the quality of included studies and adjustment for potential confounders. Meta-analysis of randomized controlled trials did not reveal any significant association between AGIs and cancer risk. Meta-analysis of observational studies indicated that AGIs may decrease the risk of cancer in individuals with diabetes.

Hypoglycemic agents and potential anti-inflammatory activity

Current literature shows an association of diabetes and secondary complications with chronic inflammation. Evidence of these immunological changes include altered levels of cytokines and chemokines, changes in the numbers and activation states of various leukocyte populations, apoptosis, and fibrosis during diabetes. Therefore, treatment of diabetes and its complications may include pharmacological strategies to reduce inflammation. Apart from anti-inflammatory drugs, various hypoglycemic agents have also been found to reduce inflammation that could contribute to improved outcomes. Extensive studies have been carried out with thiazolidinediones (peroxisome proliferator-activated receptor-γ agonist), dipeptidyl peptidase-4 inhibitors, and metformin (AMP-activated protein kinase activator) with each of these classes of compounds showing moderate-to-strong anti-inflammatory action. Sulfonylureas and alpha glucosidase inhibitors appeared to exert modest effects, while the injectable agents, insulin and glucagon-like peptide-1 receptor agonists, may improve secondary complications due to their anti-inflammatory potential. Currently, there is a lack of clinical data on anti-inflammatory effects of sodium–glucose cotransporter type 2 inhibitors. Nevertheless, for all these glucose-lowering agents, it is essential to distinguish between anti-inflammatory effects resulting from better glucose control and effects related to intrinsic anti-inflammatory actions of the pharmacological class of compounds.

Acarbose Decreases the Rheumatoid Arthritis Risk of Diabetic Patients and Attenuates the Incidence and Severity of Collagen-induced Arthritis in Mice

Acarbose has been found to decrease some inflammatory parameters in diabetic patients. This study aimed to examine the influence of acarbose on rheumatoid arthritis (RA) risk in diabetes mellitus (DM) patients and on the incidence and severity of collagen-induced arthritis (CIA) in mice. In a nationwide, matched case–control study, we identified 723 incident RA cases and selected 7,230 age-, sex- and RA diagnosis date–matched controls from all newly treated DM patients. We found that use of acarbose at > 16,950 mg per year was associated with a lower RA risk (odds ratio 0.60; 95% CI, 0.41–0.89). In the CIA mouse study, acarbose was orally administered from days -7 to 38 relative to type II collagen (CII) immunization. The results revealed that acarbose at the dose of 500 mg/kg/day attenuated the incidence and severity of arthritis and the expression of proinflammatory cytokines, including TNF-α, IL-6 and IL-17 in the paw tissues. Acarbose further decreased the productions of anti-CII-IgG, IL-17 and IFN-γ by collagen-reactive lymph node cells. This work suggests that the use of acarbose decreased RA risk in DM patients and the incidence of CIA in mice. Acarbose also attenuated the severity of CIA via anti-inflammatory and immunomodulatory effects.

Therapeutic potential of α-glucosidase inhibitors in type 2 diabetes mellitus: an evidence-based review

INTRODUCTION

Postprandial hyperglycemia (PPHG) contributes to micro- and macro-vascular complications more than fasting hyperglycemia in patients with type 2 diabetes mellitus. Due to the traditional carbohydrate-rich diet, Asians, particularly Indians and Chinese need agents to control the higher risk of uncontrolled PPHG. Targeting PPHG with α-glucosidase inhibitors (AGIs), either alone or in combination with other oral hypoglycemic agents and insulin, provide overall glycemic control with transient mild gastrointestinal disorders. Treatment with AGIs, especially acarbose, has also shown to provide beneficial effects on lipid levels, blood pressure, coagulation factors, carotid intima-media thickness and endothelial dysfunction. New insights of acarbose therapy obtained like increased activity of gut hormones and improved gut microbiota may explain the benefits on weight, whereas increased production of H2 may explains its cardiovascular benefits to some extent.

AREAS COVERED

A systematic search strategy was developed to identify randomized controlled trials in MEDLINE, PubMed, EMBASE and ongoing trials databases.

EXPERT OPINION

AGIs as a class and acarbose in particular, are most useful in combatting PPHG and glucose variability across the spectrum of diabetes therapy, particularly in Asian patients. Together with their effects on incretin hormones and gut-microbiota AGIs can be considered beyond glycemic control as 'cardio-protective agents.'

Acarbose: safe and effective for lowering postprandial hyperglycaemia and improving cardiovascular outcomes

α-Glucosidase inhibitors (AGIs) are a class of oral glucose-lowering drugs used exclusively for treatment or prevention of type 2 diabetes mellitus. AGIs act by altering the intestinal absorption of carbohydrates through inhibition of their conversion into simple sugars (monosaccharides) and thus decrease the bioavailability of carbohydrates in the body, significantly lowering blood glucose levels. The three AGIs used in clinical practice are acarbose, voglibose and miglitol. This review will focus on the cardiovascular properties of acarbose. The current available data suggest that AGIs (particularly acarbose) may be safe and effective for the treatment of prediabetes and diabetes.

Targeting Inflammation Through a Physical Active Lifestyle and Pharmaceuticals for the Treatment of Type 2 Diabetes

Evidence exists that interleukin (IL)-1β is involved in pancreatic β-cell damage, whereas TNF-α appears to be a key molecule in peripheral insulin resistance. Although increased plasma levels of IL-6 are seen in individuals with type 2 diabetes, mechanistic studies suggest that moderate acute elevations in IL-6, as provoked by exercise, exert anti-inflammatory effects by an inhibition of TNF-α and by stimulating IL-1 receptor antagonist (ra), thereby limiting IL-1β signaling. A number of medical treatments have anti-inflammatory effects. IL-1 antagonists have been tested in clinical studies and appear very promising. Also, there is a potential for anti-TNF-α strategies and salsalate has been shown to improve insulin sensitivity in clinical trials. Furthermore, the anti-inflammatory potential of statins, antagonists of the renin-angiotensin system, and glucose-lowering agents are discussed. While waiting for the outcome of long-term clinical pharmacological trials, it should be emphasized that physical activity represents a natural strong anti-inflammatory intervention with little or no side effects.

Comparison of glucose lowering effect of metformin and acarbose in type 2 diabetes mellitus: a meta-analysis

BACKGROUND

Metformin is the first-line oral hypoglycemic agent for type 2 diabetes mellitus recommended by international guidelines. However, little information exists comparing it with acarbose which is also commonly used in China. This study expanded knowledge by combining direct and indirect evidence to ascertain the glucose lowering effects of both drugs.

METHODS

PubMed (1980- December 2013) and China National Knowledge Infrastructure databases (1994-January 2014) were systematically searched for eligible randomized controlled trials from Chinese and English literatures. Meta-analysis was conducted to estimate the glucose lowering effects of metformin vs. acarbose, or either of them vs. common comparators (placebo or sulphonylureas), using random- and fixed-effect models. Bucher method with indirect treatment comparison calculator was applied to convert the summary estimates from the meta-analyses into weighted-mean-difference (WMD) and 95% confidence intervals (CIs) to represent the comparative efficacy between metformin and acarbose.

RESULTS

A total of 75 studies were included in the analysis. In direct comparison (8 trials), metformin reduced glycosylated hemoglobin (HbA1c) by 0.06% more than acarbose, with no significant difference (WMD,-0.06%; 95% CI, -0.32% to 0.20%). In indirect comparisons (67 trials), by using placebo and sulphonylureas as common comparators, metformin achieved significant HbA1c reduction than acarbose, by -0.38% (WMD,-0.38%, 95% CI, -0.736% to -0.024%) and -0.34% (WMD, -0.34%, 95% CI, -0.651% to -0.029%) respectively.

CONCLUSION

The glucose lowering effects of metformin monotherapy and acarbose monotherapy are the same by direct comparison, while metformin is a little better by indirect comparison. This implies that the effect of metformin is at least as good as acarbose's.

Influence of Acarbose on Plasma Glucose Fluctuations in Insulin-Treated Patients with Type 2 Diabetes: A Pilot Study

Background and Aims. To evaluate the effect of adding acarbose on glycemic excursions measured by continuous glucose monitoring system (CGMS) in patients with type 2 diabetes mellitus (T2DM) already on insulin therapy. Materials and Methods. This was an opened and unblended study. 134 patients with T2DM were recruited. After initial rapidly corrected hyperglycaemia by continuous subcutaneous insulin infusion (CSII) for 7 d, a 4-6-day premixed insulin titration period subsequently followed. Patients were then randomized 1 : 1 to acarbose plus insulin group or insulin therapy group for 2 weeks. CGMS was used to measure glucose fluctuations for at least 3 days after therapy cessation. Results. Patients in acarbose plus insulin group achieved a significant improvement of MAGE compared to that of insulin therapy only group (5.56 ± 2.16 versus 7.50 ± 3.28 mmol/L, P = 0.044), accompanied by a significant decrease in the incremental AUC of plasma glucose concentration above 10.0 mmol/L (0.5 [0.03, 0.9] versus 0.85 [0.23,1.4]  mmol/L per day, P = 0.037). Conclusions. Add-on acarbose to insulin therapy further improves glucose fluctuation in patients with T2DM. This study was registered with ClinicalTrials.gov registration number ChiCTR-TRC-11001218.

Comparison of vildagliptin and glimepiride: effects on glycaemic control, fat tolerance and inflammatory markers in people with type 2 diabetes

AIMS

To compare the effects of vildagliptin with those of glimepiride on glycaemic control, fat tolerance and inflammatory markers in people with Type 2 diabetes mellitus receiving metformin treatment.

METHODS

A total of 167 participants were randomized to vildagliptin 50 mg twice a day or glimepiride 2 mg three times a day, for 6 months. We evaluated the following variables: BMI; glycaemic control; fasting plasma insulin; homeostatic model assessment of insulin resistance index; fasting plasma proinsulin; glucagon; lipid profile; adiponectin; high-sensitivity C-reactive protein; interleukin-6; and tumour necrosis factor-α. A euglycaemic-hyperinsulinaemic clamp procedure and an oral fat load test were also performed.

RESULTS

Despite a similar decrease in HbA1c levels (P = 0.009, and P = 0.008, respectively), body weight increased with glimepiride (P = 0.048 vs baseline) and decreased with vildagliptin (P = 0.041 vs baseline and vs glimepiride). Fasting plasma insulin and homeostatic model assessment of insulin resistance index were significantly lower with vildagliptin compared with glimepiride (P = 0.035 and 0.047). M value, an index of insulin sensitivity, increased with vildagliptin, both compared with baseline and with glimepiride (P = 0.028 and 0.039, respectively). Vildagliptin improved all post-oral fat load peaks of lipid profile compared with glimepiride. Adiponectin levels were higher (P = 0.035) and high-sensitivity C-reactive protein levels were lower (P = 0.038) with vildagliptin vs glimepiride. During the oral fat load test, interleukin-6, high-sensitivity C-reactive protein and tumour necrosis factor-α peaks were lower and adiponectin peak was higher in the vildagliptin group than in the glimepiride group. There was a higher dropout rate as a result of hypoglycaemia in the glimepiride group than in the vildagliptin group.

CONCLUSIONS

Vildagliptin was more effective than glimepiride in reducing post-oral fat load peaks of lipid-trafficking adipocytokines and inflammatory markers.

Acarbose monotherapy and weight loss in Eastern and Western populations with hyperglycaemia: an ethnicity-specific meta-analysis

OBJECTIVE

To demonstrate if weight loss achieved with acarbose in individuals with hyperglycaemia differs between Eastern and Western populations.

METHODS

Databases and reference lists of clinical trials on acarbose were searched. Eligible studies were randomised controlled trials of acarbose monotherapy in populations with hyperglycaemia of more than 12-week duration that provided data on body weight (BW) or body mass index (BMI).

RESULTS

A total of 34 trials (6082 participants) were included. The effect of acarbose on BW was superior to that of placebo [weighted mean difference (WMD) = -0.52, 95% confidence interval (CI) -0.78 to -0.25], nateglinide (WMD = -1.33, 95% CI -1.51 to -0.75) and metformin (WMD = -0.67, 95% CI -1.14 to -0.20). Compared with placebo, there was a significantly greater weight loss of 0.92 kg (p < 0.05, I(2)  = 88.8%) with acarbose in Eastern populations (WMD = -1.20, 95% CI -1.51 to -0.75) than that in Western populations (WMD = -0.28, 95% CI -0.59 to 0.03). Across all studies, the acarbose group achieved a significantly larger absolute weight loss of (change from baseline) 1.35 kg (p < 0.05, I(2)  = 94.3%) in Eastern populations (WMD = -2.26, 95% CI -2.70 to -1.81) than in Western populations (WMD = -0.91, 95% CI -1.36 to -0.47). Nevertheless, the possible risk of bias in Eastern studies may influence the results.

CONCLUSION

The effect of acarbose on weight loss seems to be more pronounced in Eastern than in Western populations with hyperglycaemia, and is superior to that of placebo, nateglinide and metformin across both ethnicities.

High-throughput screening of FDA-approved drugs using oxygen biosensor plates reveals secondary mitofunctional effects

Repurposing of FDA-approved drugs with effects on mitochondrial function might shorten the critical path to mitochondrial disease drug development. We improved a biosensor-based assay of mitochondrial O2 consumption, and identified mitofunctional defects in cell models of LHON and FXTAS. Using this platform, we screened a 1600-compound library of clinically used drugs. The assay identified drugs known to affect mitochondrial function, such as metformin and decoquinate. We also identified several drugs not previously known to affect mitochondrial respiration including acarbose, metaraminol, gallamine triethiodide, and acamprosate. These previously unknown 'mitoactives' represent novel links to targets for mitochondrial regulation and potentially therapy, for mitochondrial disease.

Vildagliptin compared to glimepiride on post-prandial lipemia and on insulin resistance in type 2 diabetic patients

OBJECTIVES

To evaluate the effects of vildagliptin compared to glimepiride on glycemic control, insulin resistance and post-prandial lipemia.

MATERIAL AND METHODS

167 type 2 diabetic patients, not adequately controlled by metformin, were randomized to vildagliptin 50 mg twice a day or glimepiride 2 mg three times a day for 6 months, in a double blind, randomized clinical trial. We evaluated: body mass index (BMI), glycemic control, fasting plasma insulin (FPI), homeostasis model assessment insulin resistance index (HOMA-IR), fasting plasma proinsulin (FPPr), glucagon, lipid profile, resistin, retinol binding protein-4 (RBP-4), visfatin and vaspin. Furthermore, at the randomization and at the end of the study all patients underwent an euglycemic hyperinsulinemic clamp to evaluate M value and an oral fat load.

RESULTS

Despite a similar decrease of glycated hemoglobin, there were an increase of body weight with glimepiride + metformin and a decrease with vildagliptin + metformin. Fasting plasma insulin increased with glimepiride + metformin, while it did not change with vildagliptin + metformin. Vildagliptin + metformin improved lipid profile. Regarding insulin sensitivity, vildagliptin + metformin increased M value. Resistin, RBP-4, vaspin and visfatin were decreased by vildagliptin + metformin, but in group to group comparison, only vaspin reduction resulted statistically significant. Vildagliptin + metformin reduced post-prandial lipemia and insulinemia compared to glimepiride + metformin.

CONCLUSION

Vildagliptin, in addition to metformin, was more effective than glimepiride + metformin in reducing insulin resistance and post-prandial lipemia.

The dipeptidyl peptidase-4 inhibitor vildagliptin does not affect ex vivo cytokine response and lymphocyte function in patients with type 2 diabetes mellitus

AIMS

The enzyme dipeptidyl peptidase-4 (DPP-4) is a key player in the degradation of incretin hormones that are involved in glucose metabolism. DPP-4 is also expressed on immune cells and is associated with several immunological functions. Some studies have reported increased rates of infections in patients treated with DPP-4 inhibitors. We therefore assessed whether treatment with the DPP-4 inhibitor vildagliptin affected cytokine production and T-cell differentiation.

METHODS

Patients with type 2 diabetes were treated with vildagliptin or an active comparator, acarbose, for four weeks, in a randomized cross-over trial. Blood was sampled at the end of each treatment period and peripheral blood mononuclear cells were isolated and stimulated with a broad spectrum of pattern recognition receptor agonists.

RESULTS

Serum cytokine concentrations and ex vivo cytokine production (both monocyte and T-cell derived) did not differ during treatment with vildagliptin compared to acarbose. Similarly, ex vivo relative upregulation of mRNA transcription of T-cell lineage specific transcription factors was unaffected by vildagliptin treatment.

CONCLUSIONS

These data show that a four-week treatment with vildagliptin in patients with type 2 diabetes mellitus does not result in a significant modulation of cytokine responses. This observation suggests that inhibition of DDP-4 does not lead to an increased risk of infection by diminishing cytokine production.

Cardiovascular risks and benefits with oral drugs for Type 2 diabetes mellitus

Type 2 diabetes mellitus affects approximately 321 million people worldwide. It is estimated that about half of these patients will die from cardiovascular complications. In spite of these statistics, medications for diabetes are approved based not on outcomes, but on surrogate markers such as blood glucose or glycosylated hemoglobin. In recent years, however, the safety of diabetes medications has come under scrutiny, and more studies are being undertaken to determine the effect(s) of the medications on actual outcomes. In this review the authors review available study results for all of the currently approved classes of oral medications for Type 2 diabetes, and discuss the possible mechanisms for the findings. More studies are necessary for many of these classes, however, to make definitive recommendations regarding their cardiovascular effects.

A review of the efficacy and safety of oral antidiabetic drugs

INTRODUCTION

Additional oral antidiabetic agents to metformin, sulfonylureas (SU) and thiazolidinediones (TZD) are approved for the treatment of type 2 diabetes.

AREAS COVERED

The efficacy and safety of metformin, SUs, TZDs, dipeptidyl peptidase-IV (DPP-4) inhibitors, meglitinide analogs, α-glucosidase inhibitors (AGIs), bile-acid sequestrants (BAS) and bromocriptine will be reviewed.

EXPERT OPINION

Several new oral agents have been approved for type 2 diabetes management in recent years. It is important to understand the efficacy and safety of these medications in addition to the older agents to best maximize oral drug therapy for diabetes. Of the recently introduced oral hypoglycemic/antihyperglycemic agents, the DPP-4 inhibitors are moderately efficacious compared with mainstay treatment with metformin with a low side-effect profile and have good efficacy in combination with other oral agents and insulin. They are a recommended alternative when metformin use is limited by gastrointestinal (GI) side effects or when SU treatment results in significant hypoglycemia or weight gain. Meglitinide analogs are limited by their frequent dosing, expense and hypoglycemia (repaglinide > nateglinide), while AGIs are also limited by their dosing schedule and GI side-effect profile. BAS and bromocriptine have the lowest efficacy with regard to HbA(1c) reduction, also are plagued by GI adverse reactions, but have a low risk of hypoglycemia.

α-Glucosidase inhibitors and their use in clinical practice

Post-prandial hyperglycemia still remains a problem in the management of type 2 diabetes mellitus. Of all available anti-diabetic drugs, α-glucosidase inhibitors seem to be the most effective in reducing post-prandial hyperglycemia. We conducted a review analyzing the clinical efficacy and safety of α-glucosidase inhibitors, both alone and in combination with other anti-diabetic drugs, with respect to glycemic control, inflammation and atherosclerosis. α-Glucosidase inhibitors proved to be effective and safe both in monotherapy and as an add-on to other anti-diabetic drugs. Compared to miglitol and voglibose, acarbose seems to have some additive effects such as stabling carotid plaques, and reducing inflammation. Acarbose also proved to reverse impaired glucose tolerance to normal glucose tolerance.

Vitexin and isovitexin from the Leaves of Ficus deltoidea with in-vivo α-glucosidase inhibition

ETHNOPHARMACOLOGICAL RELEVANCE

The leaves of Ficus deltoidea are used as a traditional medicine by diabetes patients in Malaysia.

AIM OF THE STUDY

The objective of the study is to identify and evaluate bioactive constituents with in vivo α-glucosidase inhibition.

MATERIALS AND METHODS

The partitioned extracts, subfractions and pure bioactive constituents were subjected to α-glucosidase inhibition assay. The identified bioactive constituents were administered orally to sucrose loaded normoglycemic mice and induced diabetic rats. The postprandial blood glucose levels were monitored at 30 min interval. Acute toxicity was evaluated in both normoglycemic mice and induced diabetic rats.

RESULTS

Bioactivity guided fractionation led to the isolation of both vitexin (1) and isovitexin (2). Oral administration of 1mg/kg of either vitexin (1) or isovitexin (2) significantly (p<0.05) reduced the postprandial blood glucose level in sucrose loaded normoglycemic mice at 30 min. The percentage of postprandial blood glucose reduction was highest in sucrose loaded induced diabetic rats administered orally with 200mg/kg of vitexin (1) or 100mg/kg of isovitexin (2). Both vitexin (1) and isovitexin (2) did not exert any signs of toxicity at the highest dose of 2g/kg administered orally to normoglycemic mice and induced diabetic rats.

CONCLUSION

Both the C-glycosyl bioflavonoids, namely, vitexin (1) and isovitexin (2) exhibited in vivo α-glucosidase inhibition.

Efficacy and safety profile evaluation of acarbose alone and in association with other antidiabetic drugs: a systematic review

BACKGROUND

Epidemiologic studies have revealed that postprandial hyperglycemia significantly contributes to high glycated hemoglobin concentrations and could be linked to the development of chronic diabetic complications.

OBJECTIVE

The purpose of our review was to evaluate the clinical efficacy and safety profile of treatment with acarbose alone and combined with other antidiabetic drugs.

METHODS

A systematic search strategy was developed to identify randomized controlled trials included in MEDLINE and the Cochrane Register of Controlled Trials. The terms acarbose, α-glucosidase inhibitors, type 2 diabetes, adverse events, combination therapy, and postprandial glucose were incorporated into an electronic search strategy that included the Dickersin filter for randomized controlled trials. To qualify for inclusion, clinical trials had to be randomized trials comparing treatment with acarbose at any dosage with any other antidiabetic drug in patients with type 2 diabetes mellitus or impaired glucose tolerance. Eligible trials had to present results on glycemic control or adverse events. Trial participants needed to be affected by type 2 diabetes mellitus or have impaired glucose tolerance, and the intervention had to include acarbose at any dosage as monotherapy or combined with other antidiabetic drugs. A validated 3-item scale was used to evaluate the overall reporting quality of the trials selected for inclusion in the present review. Nineteen trials were included.

RESULTS

Treatment with acarbose significantly reduced glycated hemoglobin levels when given as monotherapy and as an add-on to other antidiabetic drug treatment (P < 0.0001). Acarbose treatment was effective in patients with uncontrolled type 2 diabetes and in patients with apparently good metabolic control owing to its positive effect on postprandial hyperglycemia (P < 0.0001). Treatment with acarbose seemed to improve the lipid profile (P < 0.05), reduce circulating levels of cell adhesion molecules (P < 0.05), reduce intima-media thickness progression (P = 0.01), and reverse impaired glucose tolerance to normal glucose tolerance (P < 0.0001).

CONCLUSIONS

When current therapy is not adequate to obtain glycemic control, acarbose could be an option as monotherapy and as an add-on to other antidiabetic drug treatment, especially when postprandial hyperglycemia is the main concern. Long-term studies are needed to determine whether the effects observed with acarbose use are maintained over the years.

The beneficial effect of α-glucosidase inhibitor on glucose variability compared with sulfonylurea in Taiwanese type 2 diabetic patients inadequately controlled with metformin: preliminary data

AIMS

Although sulfonylurea added to metformin is the first oral drug combination regimen for patients with type 2 diabetes recommended by the American Diabetes Association/European Association for the Study of Diabetes consensus statement, it does not allow for individualizing and optimizing therapy with respect to sustaining glycemic control and the reduction of glucose variability. We therefore sought to investigate acarbose as an alternative to glibenclamide in combination with metformin and compare the effects on metabolic control and glucose variability.

METHODS

Type 2 diabetic patients 30-70 years of age with glycosylated hemoglobin 7.0%-11.0% while treated with one or two oral antidiabetic drugs were successively enrolled. After 8 weeks of run-in with metformin 500 mg thrice daily, either acarbose 50 mg or glibenclamide 2.5 mg three times daily was randomly added on and force titrated to acarbose 100 mg or glibenclamide 5.0 mg three times daily for the subsequent 16 weeks. Demographic data, biochemical data and continuous glucose monitoring system data were recorded upon randomization and at the end of the study. Various parameters that measure glucose variability were derived from the continuous glucose monitoring system data.

RESULTS

Of the 51 type 2 diabetes patients enrolled, data from 40 subjects, 20 in each group, were analyzed after excluding those unqualified information. Both drug combinations improved glycemic control. Glucose variability, expressed as mean amplitude of glycemic excursion or continuous overall net glycemic action and mean of daily differences, decreased significantly (all P<.05) after the addition of acarbose but not glibenclamide. The acarbose-metformin combination has the additional benefits of weight reduction and shorter durations of hyperglycemia compared with metformin monotherapy.

CONCLUSIONS

This study suggests that both intraday and interday glucose variability are more effectively reduced by the acarbose-metformin combination than by the glibenclamide-metformin combination, while both combinations reduce the overall glucose level equally.