Metformin and pancreatic neuroendocrine tumors:A systematic review and meta-analysis

BACKGROUND Most patients with advanced pancreatic neuroendocrine tumors(pNETs)die due to tumor progression.Therefore,identifying new therapies with low toxicity and good tolerability to use concomitantly with the established pNET treatment is relevant.In this perspective,metformin is emerging as a molecule of interest.Retrospective studies have described metformin,a widely used agent for the treatment of patients with type 2 diabetes mellitus(T2DM),to be effective in modulating different tumor-related events,including cancer incidence,recurrence and survival by inhibiting mTOR phosphorylation.This systematic review evaluates the role of T2DM and metformin in the insurgence and post-treatment outcomes in patients with pNET.AIM To systematically analyze and summarize evidence related to the diagnostic and prognostic value of T2DM and metformin for predicting the insurgence and posttreatment outcomes of pNET.METHODS A systematic review of the published literature was undertaken,focusing on the role of T2DM and metformin in insurgence and prognosis of pNET,measured through outcomes of tumor-free survival(TFS),overall survival and progression free survival.RESULTS A total of 13 studies(5674 patients)were included in this review.Analysis of 809 pNET cases from five retrospective studies(low study heterogeneity with I^(2)=0%)confirms the correlation between T2DM and insurgence of pNET(OR=2.13,95%CI=1.56-4.55;P<0.001).The pooled data from 1174 pNET patients showed the correlation between T2DM and post-treatment TFS in pNET patients(hazard ratio=1.84,95%CI=0.78-2.90;P<0.001).The study heterogeneity was intermediate,with I^(2)=51%.A few studies limited the possibility of performing pooled analysis in the setting of metformin;therefore,results were heterogeneous,with no statistical relevance to the use of this drug in the diagnosis and prognosis of pNET.CONCLUSION T2DM represents a risk factor for the insurgence of pNET and is a significant predictor of poor post-treatment TFS of pNET patients.Unfortunately,a few studies with heterogeneous results limited the possibility of exploring the effect of metformin in the diagnosis and prognosis of pNET.

Promising use of metformin in treating neurological disorders:biomarker-guided therapies

Neurological disorders are a diverse group of conditions that affect the nervous system and include neurodegenerative diseases(Alzheimer’s disease,multiple sclerosis,Parkinson’s disease,Huntington’s disease),cerebrovascular conditions(stroke),and neurodevelopmental disorders(autism spectrum disorder).Although they affect millions of individuals around the world,only a limited number of effective treatment options are available today.Since most neurological disorders express mitochondria-related metabolic perturbations,metformin,a biguanide type II antidiabetic drug,has attracted a lot of attention to be repurposed to treat neurological disorders by correcting their perturbed energy metabolism.However,controversial research emerges regarding the beneficial/detrimental effects of metformin on these neurological disorders.Given that most neurological disorders have complex etiology in their pathophysiology and are influenced by various risk factors such as aging,lifestyle,genetics,and environment,it is important to identify perturbed molecular functions that can be targeted by metformin in these neurological disorders.These molecules can then be used as biomarkers to stratify subpopulations of patients who show distinct molecular/pathological properties and can respond to metformin treatment,ultimately developing targeted therapy.In this review,we will discuss mitochondria-related metabolic perturbations and impaired molecular pathways in these neurological disorders and how these can be used as biomarkers to guide metformin-responsive treatment for the targeted therapy to treat neurological disorders.

Metformin alleviates spinal cord injury by inhibiting nerve cell ferroptosis through upregulation of heme oxygenase-1 expression

Previous studies have reported upregulation of heme oxygenase-1 in different central nervous system injury models.Heme oxygenase-1 plays a critical anti-inflammatory role and is essential for regulating cellular redox homeostasis.Metformin is a classic drug used to treat type 2 diabetes that can inhibit ferroptosis.Previous studies have shown that,when used to treat cardiovascular and digestive system diseases,metformin can also upregulate heme oxygenase-1 expression.Therefore,we hypothesized that heme oxygenase-1 plays a significant role in mediating the beneficial effects of metformin on neuronal ferroptosis after spinal cord injury.To test this,we first performed a bioinformatics analysis based on the GEO database and found that heme oxygenase-1 was upregulated in the lesion of rats with spinal cord injury.Next,we confirmed this finding in a rat model of T9 spinal cord compression injury that exhibited spinal cord nerve cell ferroptosis.Continuous intraperitoneal injection of metformin for 14 days was found to both upregulate heme oxygenase-1 expression and reduce neuronal ferroptosis in rats with spinal cord injury.Subsequently,we used a lentivirus vector to knock down heme oxygenase-1 expression in the spinal cord,and found that this significantly reduced the effect of metformin on ferroptosis after spinal cord injury.Taken together,these findings suggest that metformin inhibits neuronal ferroptosis after spinal cord injury,and that this effect is partially dependent on upregulation of heme oxygenase-1.

Enhancing metformin-induced tumor metabolism destruction by glucose oxidase for triple-combination therapy

Despite decades of laboratory and clinical trials,breast cancer remains the main cause of cancer-related disease burden in women.Considering the metabolism destruction effect of metformin(Met)and cancer cell starvation induced by glucose oxidase(GOx),after their efficient delivery to tumor sites,GOx and Met may consume a large amount of glucose and produce sufficient hydrogen peroxide in situ.Herein,a pH-responsive epigallocatechin gallate(EGCG)-conjugated low-molecular-weight chitosan(LC-EGCG,LE)nanoparticle(Met–GOx/Fe@LE NPs)was constructed.The coordination between iron ions(Fe3+)and EGCG in this nanoplatform can enhance the efficacy of chemodynamic therapy via the Fenton reaction.Met–GOx/Fe@LE NPs allow GOx to retain its enzymatic activity while simultaneously improving its stability.Moreover,this pH-responsive nanoplatform presents controllable drug release behavior.An in vivo biodistribution study showed that the intracranial accumulation of GOx delivered by this nanoplatform was 3.6-fold higher than that of the free drug.The in vivo anticancer results indicated that this metabolism destruction/starvation/chemodynamic triple-combination therapy could induce increased apoptosis/death of tumor cells and reduce their proliferation.This triple-combination therapy approach is promising for efficient and targeted cancer treatment.

Effect of metformin and Pioglitazone on insulin dose reduction in type 2 diabetes mellitus patients: An open level comparative prospective study

Insulin therapy cause weight gain and may increase its own requirement. Type 2 diabetes mellitus is associated with insulin resistance and affect both endogenous and exogenous insulin effect. Metformin and Pioglitazone, commonly used insulin sensitizers, have the potentiality of reducing the insulin dose, in Type-2 diabetes mellitus (T2DM) patients. This study was held to assess and compare such potentiality. 40 T2DM patients not controlled by diet, exercise and oral antidiabetic agents were selected for this study. Study had observed that Pioglitazone and metformin both significantly had reduced the dose of insulin. But metformin reduce the dose of insulin significantly more than that of Pioglitazone. Metformin had reduced the triglyceride, LDL-c, waist hip ratio significantly but modestly increased serum lactic acid and HDL-c. It can be concluded that co-administration of metformin with insulin is more beneficial in relation to the dose of insulin, waist hip ratio, and lipid modification when compare to Pioglitazone.

Effects of Metformin and Pioglitazone on impaired glucose tolerance patients—An open level prospective study

Introduction: impaired glucose tolerance (IGT) often leads to type 2 diabetes (T2DM) and macro vascular disease;and usually associated with insulin resistance. Pioglitazone and metformin are commonly used insulin sensitizers (IS);and can prevent or delay the development T2DM and macro vascular disease. This study was deployed to search the better IS between these two in relation to plasma glucose and lipid control;and physical parameter altering effect. Materials and methods: 100 IGT patients selected randomly from outpatients department following prefixed inclusion and exclusion criteria. Pioglitazone and metformin were administered sequentially. Washout period was 2 weeks. Total follow up period was 24 weeks. Results: 70 IGT patients had completed the study. Metformin had reduced plasma glucose (fasting & postprandial), lipids and physical parameters significantly (p < 0.05) more than Pioglitazone. Discussion: Metformin, a hepatic insulin sensitizer, is more effective than PPAR-□ agonist Pioglitazone in the treatment of IGT;and this is due to the expression of PPAR-□ is more in adipose tissue but postprandial utilization of plasma glucose is more in muscle tissue.

Synergistic Effects of Glutamine Deprivation and Metformin in Acute Myeloid Leukemia

Objective The metabolic reprogramming of acute myeloid leukemia(AML)cells is a compensatory adaptation to meet energy requirements for rapid proliferation.This study aimed to examine the synergistic effects of glutamine deprivation and metformin exposure on AML cells.Methods SKM-1 cells(an AML cell line)were subjected to glutamine deprivation and/or treatment with metformin or bis-2-(5-phenylacetamido-1,2,4-thiadiazol-2-yl)ethyl sulfide(BPTES,a glutaminase inhibitor)or cytarabine.Cell viability was detected by Cell Counting Kit-8(CCK-8)assay,and cell apoptosis and reactive oxygen species(ROS)by flow cytometry.Western blotting was conducted to examine the levels of apoptotic proteins,including cleaved caspase-3 and poly(ADP-ribose)polymerase(PARP).Moreover,the human long noncoding RNA(lncRNA)microarray was used to analyze gene expression after glutamine deprivation,and results were confirmed with quantitative RT-PCR(qRT-PCR).The expression of metallothionein 2A(MT2A)was suppressed using siRNA.Cell growth and apoptosis were further detected by CCK-8 assay and flow cytometry,respectively,in cells with MT2A knockdown.Results Glutamine deprivation or treatment with BPTES inhibited cell growth and induced apoptosis in SKM-1 cells.The lncRNA microarray result showed that the expression of MT family genes was significantly upregulated after glutamine deprivation.MT2A knockdown increased apoptosis,while proliferation was not affected in SKM-1 cells.In addition,metformin inhibited cell growth and induced apoptosis in SKM-1 cells.Both glutamine deprivation and metformin enhanced the sensitivity of SKM-1 cells to cytarabine.Furthermore,the combination of glutamine deprivation with metformin exhibited synergistic antileukemia effects on SKM-1 cells.Conclusion Targeting glutamine metabolism in combination with metformin is a promising new therapeutic strategy for AML.

Metformin administration in prevention of colorectal polyps in type 2 diabetes mellitus patients

BACKGROUND Colorectal polyps are frequently observed in patients with type 2 diabetes mellitus(DM),posing a significant risk for colorectal cancer.Metformin,a widely prescribed biguanidine drug for type 2 DM,has been suggested to have potential chemoprophylactic effects against various cancers.AIM To explore the correlation between colorectal polyps and metformin use in type 2 DM patients.METHODS Type 2 DM patients were categorized into polyp and non-polyp groups.Following this,all patients were categorized into the type 2 DM-metformin,type 2 DM-non-metformin,and non-type 2 DM groups.Based on the baseline colonoscopy results,we performed pairwise comparisons of the incidence of colorectal polyps among the three groups.Additionally,we analyzed the relationship between colorectal polyps and the duration of metformin use and between the size and number of polyps and metformin use.Simultaneously,we focused on the specific pathological types of polyps and analyzed their relationship with metformin use.Finally,we compared the incidence of polyps between metformin and non-metformin groups according to the interval colonoscopy results.RESULTS The rate of metformin use in patients with colorectal polyps was 0.502 times that of patients without colorectal polyps[odds ratio(OR)=0.502,95%confidence interval(CI):0.365-0.689;P<0.001].The incidence of colorectal polyps did not differ significantly between the type 2 DM-metformin and non-type 2 DM groups(P>0.05).Furthermore,the correlations between the duration of metformin use and the incidence of colorectal polyps and between the size and number of polyps and metformin use were not statistically significant(P>0.05).Metformin use did not affect the incidence of colorectal polyps during interval colonoscopy(P>0.05).CONCLUSION Metformin use and colorectal polyp incidence in type 2 DM patients showed a negative correlation,independent of the hypoglycemic effect of metformin.

Mitigating diabetes-related complications:Empowering metformin with cholecalciferol and taurine supplementation in type 2 diabetic rats

BACKGROUND Type 2 diabetes is one of the most prevalent chronic diseases worldwide,significantly impacting patients'quality of life.Current treatment options like metformin(MET)effectively counteract hyperglycemia but fail to alleviate diabetes-associated complications such as retinopathy,neuropathy,nephropathy,hepatopathy,and cardiovascular diseases.AIM To propose the supplementation of cholecalciferol(CHO)and taurine(TAU)to enhance MET efficacy in controlling diabetes while minimizing the risk of associated complications.METHODS The study involved sixty rats,including ten non-diabetic control rats and fifty experimental rats with type 2 diabetes induced by streptozotocin.The experimental rats were further subdivided into positive control and treatment subgroups.The four treatment groups were randomly allocated to a single MET treatment or MET combined with supplements either CHO,TAU,or both.RESULTS Diabetic rats exhibited elevated levels of glucose,insulin,Homeostasis Model Assessment of Insulin Resistance(HOMA-IR),glycated hemoglobin percentage,lipid markers,aspartate aminotransferase,and malondialdehyde,along with reduced levels of antioxidant enzymes(catalase and superoxide dismutase).The administration of CHO and TAU supplements alongside MET in diabetic rats led to a noticeable recovery of islet mass.The antioxidative,anti-inflammatory,and anti-apoptotic properties of the proposed combination therapy significantly ameliorated the aforementioned abnormalities.CONCLUSION The supplementation of CHO and TAU with MET showed the potential to significantly improve metabolic parameters and protect against diabetic complications through its antioxidative,anti-inflammatory,and antiapoptotic effects.

The anti-neoplastic effects of metformin modulate the acquired phenotype of fbroblast cells in the breast cancer-normal fbroblast co-culture system

Intracellular communications between breast cancer and fibroblast cells were reported to be involved in cancer proliferation,growth,and therapy resitance.The hallmarks of cancer fibroblast interactions,consisting of caveolin 1(Cav1)and mono-carboxylate ransporter 4(MCT4)(metabolic coupling markers),along with IL-6,TGFB,and lactate secretion,are considered robust biomarkers predicting recurrence and metastasis.In order to promote a novel phenotype in normal fibroblasts,we predicted that breast cancer cells could be able to cause loss of Cavl and increase of MCT4,as well as elevate IL 6 and TGF in nearby nomal fibroblasts.We created a co culture model using breast cancer(4T1)and normal fibroblast(NIH3T3)cell lines cultured under specific experimental conditions in order to directly test our theory.Moreover,we show that long-term co-culture of breast cancer cells and normal fibroblasts promotes loss of Cavl and gain of MCT4 in adjacent fibroblasts and increase lactate secretion.These results were validated using the monoculture of each group separately as a control.In this system,we show that me tformin inhibits IL-6 and TGFB secretion and re expresses Cavl in both cells.However,MCT4 and lactate stayed high after treatment with metformin.In conclusion,our work shows that co-culture with breast cancer cells may cause signifcant alterations in the phenotype and secretion of normal fibroblasts.Metformin,however,may change this state and affect fibroblasts'acquired phenotypes.Moreover,mitochondrial inhibition by metformin after 8 days of treatment,signi ficantly hinders tumor growth in mouse model of breast cancer.

Metformin:A promising clinical therapeutical approach for BPH treatment via inhibiting dysregulated steroid hormones-induced prostatic epithelial cells proliferation

The occurrence of benign prostate hyperplasia(BPH)was related to disrupted sex steroid hormones,and metformin(Met)had a clinical response to sex steroid hormone-related gynaecological disease.However,whether Met exerts an antiproliferative effect on BPH via sex steroid hormones remains unclear.Here,our clinical study showed that along with prostatic epithelial cell(PEC)proliferation,sex steroid hormones were dysregulated in the serum and prostate of BPH patients.As the major contributor to dysregulated sex steroid hormones,elevated dihydrotestosterone(DHT)had a significant positive relationship with the clinical characteristics of BPH patients.Activation of adenosine 5'-monophosphate(AMP)-activated protein kinase(AMPK)by Met restored dysregulated sex steroid hormone homeostasis and exerted antiproliferative effects against DHT-induced proliferation by inhibiting the formation of androgen receptor(AR)-mediated Yes-associated protein(YAP1)-TEA domain transcription factor(TEAD4)heterodimers.Met’s anti-proliferative effects were blocked by AMPK inhibitor or YAP1 overexpression in DHT-cultured BPH-1 cells.Our findings indicated that Met would be a promising clinical therapeutic approach for BPH by inhibiting dysregulated steroid hormone-induced PEC proliferation.

Megestrol acetate plus metformin for fertility-sparing treatment of atypical endometrial hyperplasia and early-stage endometrial adenocarcinoma: a prospective study

Objective To evaluate the efficacy of medroxyprogesterone acetate(MA)plus metformin as the primary fertility-sparing treatment for atypical endometrial hyperplasia(AEH)and early-stage grade 1 endometrial adenocarcinoma(G1 EAC)and the recurrence rate after treatment.Methods Sixty patients(aged 20-42 years)with AEH and/or grade 1 EAC limited to the endometrium were enrolled prospectively and randomized into two groups(n=30)to receive oral MA treatment at the daily dose of 160 mg(control)or MA plus oral metformin(850 mg,twice a day)for at least 6 months.The treatment could extend to 12 months until a complete response(CR)was achieved,and follow-up hysteroscopy and curettage were performed every 3 months.For all the patients who achieved CR,endometrial expressions of IGFBP-rP1,p-Akt and p-AMPK were detected immunohistochemically.Results A total of 58 patients completed the treatment.After 9 months of treatment,23(76.7%)patients in the combined treatment group and 20(71.4%)in the control group achieved CR;two patients in the control group achieved CR after converting to the combined treatment.The recurrence rate did not differ significantly between the control group and combined treatment group(30.0%vs 22.7%,P>0.05).Ten(35.7%)patients in the control group experienced significant weight gain of 5.7±6.1 kg,while none of the patients receiving the combined treatment exhibited significant body weight changes.Compared with the control group,the patients receiving the combined treatment showed enhanced endometrial expressions of IGFBP-rP1 and p-AMPK with lowered p-Akt expression.Conclusion Metformin combined with MA may provide an effective option for fertility-sparing treatment of AEH and grade 1 stage IA EAC,and the clinical benefits of metformin for controlling MA-induced weight gain and promoting endometrial expressions of IGFBP-rP1 and p-AMPK while inhibiting p-Akt expression warrants further study.

Metformin promotes anti-tumor immunity in STK11 mutant NSCLC through AXIN1-dependent upregulation of multiple nucleotide metabolites

Background:Metformin has pleiotropic effects beyond glucose reduction,including tumor inhibition and immune regulation.It enhanced the anti-tumor effects of programmed cell death protein 1(PD-1)inhibitors in serine/threonine kinase 11(STK11)mutant non-small cell lung cancer(NSCLC)through an axis inhibition protein 1(AXIN1)-dependent manner.However,the alterations of tumor metabolism and metabolites upon metformin administration remain unclear.Methods:We performed untargeted metabolomics using liquid chromatography(LC)-mass spectrometry(MS)/MS system and conducted cell experiments to verify the results of bioinformatics analysis.Results:According to the Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway database,most metabolites were annotated into metabolism,including nucleotide metabolism.Next,the differentially expressed metabolites in H460(refers to H460 cells),H460_met(refers to metformin-treated H460 cells),and H460_KO_met(refers to metformin-treated Axin1-/-H460 cells)were distributed into six clusters based on expression patterns.The clusters with a reversed expression pattern upon metformin treatment were selected for further analysis.We screened out metabolic pathways through KEGG pathway enrichment analysis and found that multiple nucleotide metabolites enriched in this pathway were upregulated.Furthermore,these metabolites enhanced the cytotoxicity of activated T cells on H460 cells in vitro and can activate the stimulator of the interferon genes(STING)pathway independently of AXIN1.Conclusion:Relying on AXIN1,metformin upregulated multiple nucleotide metabolites which promoted STING signaling and the killing of activated T cells in STK11 mutant NSCLC,indicating a potential immunotherapeutic strategy for STK11 mutant NSCLC.

Statin, aspirin and metformin use and risk of hepatocellular carcinoma related outcomes following liver transplantation: A retrospective study

BACKGROUND Liver transplantation(LT)is a potentially curative therapy for patients with hepatocellular carcinoma(HCC).HCC-recurrence following LT is associated with reduced survival.There is increasing interest in chemoprophylaxis to improve HCC-related outcomes post-LT.AIM To investigate whether there is any benefit for the use of drugs with proposed chemoprophylactic properties against HCC,and patient outcomes following LT.METHODS This was a retrospective study of adult patients who received Deceased Donor LT for HCC from 2005-2022,from a single Australian centre.Drug use was defined as statin,aspirin or metformin therapy for≥29 days,within 24 months post-LT.A cox proportional-hazards model with time-dependent covariates was used for survival analysis.Outcome measures were the composite-endpoint of HCC-recurrence and all-cause mortality,HCC-recurrence and HCC-related mortality.Sensitivity analysis was performed to account for immortality time bias and statin dosing.RESULTS Three hundred and five patients were included in this study,with 253(82.95%)males with a median age of 58.90 years.Aetiologies of liver disease were 150(49.18%)hepatitis C,73(23.93%)hepatitis B(HBV)and 33(10.82%)non-alcoholic fatty liver disease(NAFLD).56(18.36%)took statins,51(16.72%)aspirin and 50(16.39%)metformin.During a median follow-up time of 59.90 months,34(11.15%)developed HCC-recurrence,48(15.74%)died,17(5.57%)from HCC-related mortality.Statin,aspirin or metformin use was not associated with statistically significant differences in the composite endpoint of HCC-recurrence or all-cause mortality[hazard ratio(HR):1.16,95%CI:0.58-2.30;HR:1.21,95%CI:0.28-5.27;HR:0.61,95%CI:0.27-1.36],HCC-recurrence(HR:0.52,95%CI:0.20-1.35;HR:0.51,95%CI:0.14-1.93;HR 1.00,95%CI:0.37-2.72),or HCC-related mortality(HR:0.32,95%CI:0.033-3.09;HR:0.71,95%CI:0.14-3.73;HR:1.57,95%CI:0.61-4.04)respectively.Statin dosing was not associated with statist-ically significant differences in HCC-related outcomes.CONCLUSION Statin,metformin or aspirin use was not associated with improved HCC-related outcomes post-LT,in a largely historical cohort of Australian patients with a low proportion of NAFLD.Further prospective,multicentre studies are required to clarify any potential benefit of these drugs to improve HCC-related outcomes.

Exploring the anti-osteoporotic potential of simvastatin and metformin: a comprehensive Mendelian randomization and animal experiment investigation

Background:Both simvastatin and metformin have demonstrated potential efficacy in osteoporosis(OP)treatment.However,there is a lack of systematic studies comparing their anti-osteoporotic effects.This study aims to compare the effects of simvastatin and metformin on OP through Mendelian randomization(MR)studies and animal experiments.Methods:Initially,we will analyze the causal impact of simvastatin or metformin treatment on OP prevalence and three common clinical OP diagnostic markers(bone mineral density(BMD),serum osteocalcin(OCN),and tartrate-resistant acid phosphatase(TRAP)levels)using genome-wide association study(GWAS)summary statistics.Additionally,we established animal models to further analyze and compare the anti-osteoporosis effects of simvastatin and metformin.8 male C57BL/6J mice(3-month-old)and 24 male C57BL/6J mice(18-month-old)were treated with simvastatin or metformin for 12 weeks.OP pathology was assessed using histology,immunohistochemistry,biomechanical tests,micro-computed tomography,and osteogenic differentiation assays.Results:In the MR analysis,metformin treatment was significantly associated with lower OP prevalence(OR(95%CI)=0.933(0.902–0.965),β=-0.0694,P<0.001)and higher BMD(OR(95%CI)=3.719(1.750–7.908),β=1.3136,P<0.001).In the animal experiment,both drugs increased bone mass,improved bone microstructure,and promoted osteoblast differentiation.However,metformin appeared more effective in several aspects.It significantly inhibited bone marrow adipocyte and osteoclast differentiation in aged mice compared to simvastatin.Additionally,metformin better promoted the expression of osteoprotegerin(OPG)and collagen type I(Col-I)in bone tissue and maintained the structure and biomechanical properties of cancellous bone.Conclusion:Both drugs significantly preserved bone homeostasis.Particularly,compared with simvastatin,metformin exhibited superior effects in inhibiting adipogenesis,enhancing the OPG/RANKL pathway,and promoting cancellous bone reconstruction.Metformin may serve as a valuable adjunct in preventing and treating OP in the elderly.

Simultaneous determination of pioglitazone and candesartan in human plasma by LC-MS/MS and its application to a human pharmacokinetic study

A simple and rapid liquid chromatography-tandem mass spectrometric(LC-MS/MS) assay method has been developed and fully validated for simultaneous quantification of pioglitazone and candesartan in human plasma.Irbesartan was used as an internal standard.The analytes were extracted from human plasma samples by solid-phase extraction technique using a Strata-X 33 mm polymeric sorbent.The reconstituted samples were chromatographed on a C18 column by using a 80:20(v/v) mixture of acetonitrile and 0.1% formic acid as the mobile phase at a flow rate of 0.8 mL/min.The calibration curves obtained were linear(rZ0.99) over the concentration range of 15-3000 ng/mL for pioglitazone and 5-608 ng/mL for candesartan.The results of the intra-and inter-day precision and accuracy studies were well within the acceptable limits.A run time of 2.7 min for each sample made it possible to analyze more than 300 plasma samples per day.The proposed method was found to be applicable to clinical studies.

Effect of pioglitazone on nerve conduction velocity of the median nerve in the carpal tunnel in type 2 diabetes patients

AIM To evaluate the impact of pioglitazone pharmacotherapy in median nerve electrophysiology in the carpal tunnel among type 2 diabetes patients.METHODS The study was executed in patients with type 2 diabetes, treated with oral drugs, categorized under pioglitazone or non-pioglitazone group(14 in each group), and who received electrophysiological evaluation by nerve conduction velocity at baseline and 3 mo.RESULTS At 3 mo, pioglitazone-category had inferior amplitude in sensory median nerve [8.5 interquartile range(IQR) = 6.5 to 11.5) vs non-pioglitazone 14.5(IQR 10.5 to 18.75)](P = 0.002). Non-pioglitazone category displayed amelioration in amplitude in the sensory median nerve [baseline 13(IQR = 9 to 16.25) vs 3 mo 8.5(IQR = 6.5 to 11.5)](P = 0.01) and amplitude in motor median nerve [baseline 9(IQR = 4.75 to 11) vs 3 mo 6.75(IQR = 4.75 to 10.25)](P = 0.049); and deterioration of terminal latency of in motor ulnar nerve [baseline 2.07(IQR = 1.92 to 2.25) vs 3 mo 2.16(IQR = 1.97 to 2.325)](P = 0.043). There was amelioration of terminal latency in sensory ulnar nerve [baseline 2.45(IQR = 2.315 to 2.88) vs 3 mo 2.37(IQR = 2.275 to 2.445) for pioglitazone group(P = 0.038).CONCLUSION Treatment with pioglitazone accentuates probability of compressive neuropathy. In spite of comparable glycemic control over 3 mo, patients treated with pioglitazone showed superior electrophysiological parameters for the ulnar nerve. Pioglitazone has favourable outcome in nerve electrophysiology which was repealed when the nerve was subjected to compressive neuropathy.

Research on the protection effect of pioglitazone for non-alcoholic fatty liver disease (NAFLD)in rats

Objective： The prevalence of non-alcoholic fatty liver disease （NAFLD） has markedly increased. Insulin resistance has been implicated in the pathogenesis of NAFLD. This study was aimed at observing the relationship between insulin resistance and NAFLD, and evaluating the role of pioglitazone （PGZ） acting as insulin-sensitizing agents in the prevention and treatment of rat fatty liver induced by high fat feeding. Methods： The rats were separated randomly into 6 groups： model group Ⅰ were fed high fat diet for 8 weeks, PGZ prevention group were given PGZ 4 mg/（kg.d） simultaneously, while control group Ⅰ were fed normal food for 8 weeks; model group Ⅱ were fed high fat diet for 16 weeks, PGZ treatment group were given PGZ 4 mg/（kg.d） orally simultaneous with high fat diet for 8 weeks after high fat feeding for 8 weeks, control group Ⅱ were fed normal food for 16 weeks. The rats were sacrificed after 8 weeks and 16 weeks respectively. Liver weight, body weight, serum activities of alanine aminotransferase （ALT）, aspartate aminotransferase （AST）, alkaline phosphatase （ALP）, tumor necrosis factor alpha （TNF-α）, fasting blood glucose （FBG）, fasting plasma insulin （FINS）, HOMA （homeostasis model assessment） insulin resistance index （HOMA-IR）, and the liver histology of rats of all groups were assayed. Results： After 8 weeks, the liver in model group Ⅰ showed typical steatosis, accompanied with mild to moderate lobular inflammatory cell infiltration, liver indexes and serum levels of ALT, AST, ALP, TNF-α were significantly increased （P〈0.05） compared with control group Ⅰ. Whereas, the degree of hepatic injury was attenuated in PGZ prevention group, liver indexes and serum levels of ALT, ALP were significantly decreased （P〈0.05） compared with model group Ⅰ. After 16 weeks, notable steatosis, and lobular inflammation were observed in model group Ⅱ rat liver, while the degree of hepatic injury was attenuated in the PGZ treatment group. Liver index, serum levels ofALT, AST, ALP, FINS and HOMA-IR were significantly increased （P〈0.05） in model group Ⅱ compared with control group Ⅱ. Whereas, in PGZ treatment group, serum levels of AST and FINS showed decreasing tendency, liver indexes, serum levels of ALT, ALP, TNF-α and HOMA-IR were significantly decreased compared with model group Ⅱ. Conclusion： Insulin resistance plays a role in the pathogenesis of NAFLD in rats. Pioglitazone can attenuate insulin resistance and biochemical and histological injury in high fat-induced fatty liver in rats.

Pioglitazone:A review of analytical methods

Pioglitazone is an oral anti-hyperglycemic agent. It is used for the treatment of diabetes mellitus type 2. It selectively stimulates nuclear receptor peroxisome proliferator-activated receptor gamma （PPAR-gamma）. It was the tenth-best-selling drug in the U.S. in 2008. This article examines published analytical methods reported so far in the literature for the determination of pioglitazone in biological samples and pharmaceutical formulations. They include various techniques like electrochemical methods, spectrophotometry, capillary electrophoresis, high-performance liquid chromatography, liquid chromatography-electrospray ionization-tandem mass spectrometry and high-performance thin layer chromatography.

Efficacy and safety of vildagliptin/pioglitazone combination therapy in Korean patients with diabetes

AIM:To assess the efficacy and safety of vildagliptin/pioglitazone combination therapy in Korean patients with type 2 diabetes mellitus(T2DM).METHODS:This was a post hoc analysis in Korean patients,from a 24-wk,randomized,active-controlled,double-blind,parallel-group,multicenter study.Eligible patients were aged between 18 and 80 years,drug naive,and had been diagnosed with T2DM [hemoglobin A1c(HbA1c):7.5-11.0 and fasting plasma glucose(FPG):【 270 mg/dL(【 15 mmol/L)].Patients were randomized(1:1:1:1) to receive the vildagliptin/pioglitazone comb ination at 100/30 mg q.d.(high-dose) or 50/15 mg q.d.(low-dose),vildagliptin 100 mg q.d.,or pioglitazone 30 mg q.d.monotherapies.The primary outcome measure was change in HbA1c from baseline to endpoint.RESULTS:The distribution of baseline demographic and clinical parameters was well balanced between treatment groups.The overall mean age,body mass index,HbA1c,FPG,and duration of disease were 50.8 years,24.6 kg/m2,8.6,10.1 mmol/L,and 2.2 years,respectively.Adjusted mean changes(± standard error) in HbA1c from baseline(~8.7) to week 24 endpoint were-2.03 ± 0.16(high-dose,N = 34),-1.88 ± 0.15(low-dose,N = 34),-1.31 ± 0.21(vildagliptin,N = 36),and-1.52 ± 0.16(pioglitazone,N = 36).The high-dose combination therapy demonstrated greater efficacy than monotherapies [vildagliptin(P = 0.029) and pioglitazone(P = 0.027)].Percentage of patients achieving HbA1c 【 7 and ≤ 6.5 was the highest in the high-dose group(76 and 68) followed by low-dose(58 and 47),vildagliptin(59 and 37),and pioglitazone(53 and 28) groups.The overall incidence of adverse events was comparable.CONCLUSION:In Korean patients,first-line treatment with high-dose combination therapy improved glycemic control compared to pioglitazone and vildagliptin monotherapies,consistent with results published for the overall study population.