Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 47
Filter
1.
Inflammation ; 46(5): 1917-1931, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37289398

ABSTRACT

New consensus indicates type 2 diabetes mellitus (T2DM) and periodontitis as comorbidity and may share common pathways of disease progression. Sulfonylureas have been reported to improve the periodontal status in periodontitis patients. Glipizide, a sulfonylurea widely used in the treatment of T2DM, has also been reported to inhibit inflammation and angiogenesis. The effect of glipizide on the pathogenicity of periodontitis, however, has not been studied. We developed ligature-induced periodontitis in mice and treated them with different concentrations of glipizide and then analyzed the level of periodontal tissue inflammation, alveolar bone resorption, and osteoclast differentiation. Inflammatory cell infiltration and angiogenesis were analyzed using immunohistochemistry, RT-qPCR, and ELISA. Transwell assay and Western bolt analyzed macrophage migration and polarization. 16S rRNA sequencing analyzed the effect of glipizide on the oral microbial flora. mRNA sequencing of bone marrow-derived macrophages (BMMs) stimulated by P. gingivalis lipopolysaccharide (Pg-LPS) after treatment with glipizide was analyzed. Glipizide decreases alveolar bone resorption, periodontal tissue degradation, and the number of osteoclasts in periodontal tissue affected by periodontitis (PAPT). Glipizide-treated periodontitis mice showed reduced micro-vessel density and leukocyte/macrophage infiltration in PAPT. Glipizide significantly inhibited osteoclast differentiation in vitro experiments. Glipizide treatment did not affect the oral microbiome of periodontitis mice. mRNA sequencing and KEGG analysis showed that glipizide activated PI3K/AKT signaling in LPS-stimulated BMMs. Glipizide inhibited the LPS-induced migration of BMMs but promoted M2/M1 macrophage ratio in LPS-induced BMMs via activation of PI3K/AKT signaling. In conclusion, glipizide inhibits angiogenesis, macrophage inflammatory phenotype, and osteoclastogenesis to alleviate periodontitis pathogenicity suggesting its' possible application in the treatment of periodontitis and diabetes comorbidity.


Subject(s)
Alveolar Bone Loss , Diabetes Mellitus, Type 2 , Periodontitis , Humans , Mice , Animals , Osteogenesis , Glipizide/metabolism , Glipizide/pharmacology , Diabetes Mellitus, Type 2/metabolism , Lipopolysaccharides/pharmacology , Proto-Oncogene Proteins c-akt/metabolism , Phosphatidylinositol 3-Kinases/metabolism , RNA, Ribosomal, 16S/metabolism , Virulence , Periodontitis/drug therapy , Periodontitis/metabolism , Osteoclasts/metabolism , Inflammation/metabolism , Macrophages/metabolism , Alveolar Bone Loss/drug therapy , Alveolar Bone Loss/prevention & control , Alveolar Bone Loss/metabolism , RNA, Messenger/metabolism
2.
Biochem Biophys Res Commun ; 645: 88-96, 2023 02 19.
Article in English | MEDLINE | ID: mdl-36680941

ABSTRACT

Increasing reports suggest insulin signalling pathway as a putative drug target against polyglutamine [poly(Q)] disorders, such as Huntington's disease (HD), Spinocerebellar ataxias (SCA) 1, 2, 3 etc. However, studies on drug-based stimulation of insulin signalling cascade to mitigate poly(Q) pathogenesis are lacking. In our study, we adopted an evidence-based approach to examine if some established insulin stimulating drug can be utilized to restrict poly(Q) aetiology in Drosophila disease models. For the first time, we report that glipizide, an FDA approved anti-diabetic drug upregulates insulin signalling in poly(Q) expressing tissues and restricts formation of inclusion bodies and neurodegeneration. Moreover, it reinstates the chromatin architecture by improving histone acetylation, which is otherwise abrogated due to poly(Q) toxicity. In view of the functional conservation of insulin signalling pathway in Drosophila and humans, our finding strongly suggests that glipizide can be repurposed as an effective treatment strategy against the neurodegenerative poly(Q) disorders. Also, with appropriate validation studies in mammalian disease models, glipizide could be subsequently considered for the clinical trials in human patients.


Subject(s)
Drosophila Proteins , Drosophila , Animals , Humans , Drosophila/metabolism , Glipizide/metabolism , Insulin/metabolism , Drosophila Proteins/metabolism , Signal Transduction , Mammals/metabolism
3.
Mol Biol Rep ; 49(2): 1151-1159, 2022 Feb.
Article in English | MEDLINE | ID: mdl-35013863

ABSTRACT

BACKGROUND: Despite commonly use for treatment of type II diabetes, possible effects of glipizide on nuclear transport and DNA damage in cells are unknown. Since clinical response of glipizide may change with aging, the aim of the study was to investigate the effect of glipizide by comparing mature and senescent adipocytes. METHODS AND RESULTS: The effects of glipizide were investigated in 3T3-L1 adipocytes. Effective and lethal doses were determined by real-time monitoring iCELLigence system. Comet assay was performed to determine DNA damage and quantitative PCR was conducted to detect gene expression levels. RAN expressions were found to be up regulated in mature 180 µM glipizide treated adipocytes compared to control group (p < 0.05); whereas down regulated in senescent 180 µM glipizide treated adipocytes compared to their control adipocytes (p < 0.05). Olive Tail Moment values were significantly higher in mature 180 µM glipizide treated adipocytes (MTG) and senescent 180 µM glipizide treated adipocytes (STG) comparing their untreated controls (p < 0.001 and p < 0.001 respectively). Also class 5 comets that shows severe DNA damage were found to be higher in both MTG and STG groups than their controls (p < 0.001 and p < 0.001, respectively). OTM values were higher in STG than MTG (p < 0.001). CONCLUSIONS: This is the first study that reports glipizide caused DNA damage increasing with senescence in adipocytes. As a response to glipizide treatment Ran gene expression increased in mature; and decreased in senescent adipocytes. Further studies are needed to reveal the effect of glipizide on DNA and nuclear interactions in molecular level.


Subject(s)
Active Transport, Cell Nucleus/drug effects , DNA Damage/drug effects , Glipizide/pharmacology , 3T3-L1 Cells/drug effects , Active Transport, Cell Nucleus/physiology , Adipocytes/drug effects , Adipocytes/metabolism , Animals , Cell Differentiation , DNA Damage/genetics , Glipizide/adverse effects , Glipizide/metabolism , Mice
4.
Sci Rep ; 8(1): 18063, 2018 12 24.
Article in English | MEDLINE | ID: mdl-30584236

ABSTRACT

Glibenclamide and glipizide show large substantial inter-individual variation in clinical efficacy, which may be resulted from the genetic differences of metabolic enzymes and transporters in individuals. This study purposed to investigate the effect of OATP1B3 and CYP2C9 genetic polymorphisms on the transport and metabolism of glibenclamide and glipizide in human. An LC-MS method was used to determine the uptake of glibenclamide and glipizide in OATP1B3, OATP1B3 (344T > G) and OATP1B3 (699G > A)-HEK293T cells and their metabolism in CYP2C9*1, *2 and *3 recombinase system. Glibenclamide can be taken in OATP1B3 (wild-type), OATP1B3 (344T > G) and OATP1B3 (699G > A)-HEK293T cells with the Vmax values of 44.91 ± 7.97, 46.08 ± 8.69, and 37.31 ± 5.04 pmol/min/mg, while glipizide was taken in with Vmax of 16.50 ± 3.64, 16.87 ± 4.23, and 13.42 ± 2.79 pmol/min/mg, respectively. The internal clearance of glibenclamide and glipizide in OATP1B3 (699G > A) was less than that in wild-type. Glibenclamide can be metabolized in CYP2C9*1, *2 and *3 recombinase system with the Vmax values of 1.58 ± 0.71, 0.69 ± 0.25, and 0.41 ± 0.13 nmol/min/mg protein, while glipizide was metabolized with Vmax of 8.82 ± 2.78, 5.99 ± 1.95, and 2.87 ± 1.03 nmol/min/mg protein, respectively. The internal clearance of glibenclamide and glipizide in CYP2C9*2 and *3 was markedly reduced compared to that in CYP2C9*1. These results collectively demonstrate that OATP1B3 (699G > A) and CYP2C9*2 and *3 have a significant influence on the transport and metabolism of glibenclamide and glipizide.


Subject(s)
Cytochrome P-450 CYP2C9/metabolism , Glipizide/metabolism , Glyburide/metabolism , Hypoglycemic Agents/metabolism , Polymorphism, Single Nucleotide , Solute Carrier Organic Anion Transporter Family Member 1B3/metabolism , Cytochrome P-450 CYP2C9/genetics , HEK293 Cells , Humans , Mutation, Missense , Solute Carrier Organic Anion Transporter Family Member 1B3/genetics
5.
Photochem Photobiol ; 94(6): 1151-1158, 2018 11.
Article in English | MEDLINE | ID: mdl-30066952

ABSTRACT

Reactive oxygen species (ROS) have been described in their double physiological function, helping in the maintenance of health as well as contributing to oxidative stress. Diabetes mellitus is a chronical disease nearly related to oxidative stress, whose treatment (in type II variant) consists in the administration of antidiabetic compounds (Andb) such as Gliclazide (Gli) and Glipizide (Glip). In this context, as Andb may be exposed to high ROS concentrations in diabetic patients, we have studied the potential ROS-mediated degradation of Gli and Glip through photosensitized processes, in the presence of Riboflavin (Rf) vitamin. We found that singlet oxygen (O2 (1 ∆g )) participated in the Rf-sensitized photodegradation of both Andb, and also superoxide radical anion in the case of Gli. Two principal products derived from O2 (1 ∆g )-mediated degradation of Gli were identified and their chemical structures characterized, through HPLC mass spectrometry. O2 (1 ∆g )-mediated degradation products and their toxicity was assayed on Vero cell line. These studies demonstrated that neither Gli nor its photoproducts caused cytotoxic effect under the experimental conditions assayed. Our results show strong evidences of ROS-mediated Andb degradation, which may involve the reduction or loss of their therapeutic action, as well as potential cytotoxicity derived from their oxidation products.


Subject(s)
Gliclazide/chemistry , Glipizide/chemistry , Hypoglycemic Agents/chemistry , Photosensitizing Agents/chemistry , Riboflavin/chemistry , Singlet Oxygen/chemistry , Superoxides/chemistry , Animals , Biotransformation/radiation effects , Cell Survival/drug effects , Chlorocebus aethiops , Diabetes Mellitus, Type 2/drug therapy , Gliclazide/metabolism , Gliclazide/pharmacology , Glipizide/metabolism , Glipizide/pharmacology , Humans , Hypoglycemic Agents/metabolism , Hypoglycemic Agents/pharmacology , Kinetics , Light , Oxidation-Reduction , Photolysis , Photosensitizing Agents/metabolism , Riboflavin/metabolism , Singlet Oxygen/metabolism , Solutions , Spectrometry, Fluorescence , Superoxides/metabolism , Vero Cells
6.
AAPS PharmSciTech ; 19(5): 2144-2154, 2018 Jul.
Article in English | MEDLINE | ID: mdl-29714000

ABSTRACT

The aim of this research was to design and evaluate a hydrophilic matrix system for sustained release of glipizide, a weakly acidic poor soluble drug. A combination of inclusion complexation and microenvironmental pH modification techniques was utilized to improve the dissolution and pH-independent release of glipizide. Hydroxypropyl-ß-cyclodextrin (HP-ß-CD) was used as the complexation agent while sodium citrate and magnesium oxide (MgO) were used as model pH modifiers. The hydrophilic matrix tablets were prepared by powder direct compression and evaluated by in vitro dissolution study respectively in pH 6.8 and pH 1.2 dissolution media. The formulations containing MgO exhibited increased cumulative drug release from less than 40% in the reference formulation to 90% within 24 h in acidic media (pH 1.2). The release profile in acidic media was similar to the alkaline media (pH 6.8) with a similarity factor (f2) of 55.0, suggesting the weakening of the effect of pH on the dissolution efficiency of glipizide. The release profile fitted well into the Higuchi model and the dominant mechanism of drug release was Fickian diffusion while case II transport/polymer relaxation occurred. In conclusion, combining inclusion complexation agents and pH modifiers had improved the dissolution of glipizide as well as achieved the pH-independent release profile.


Subject(s)
Drug Carriers/chemical synthesis , Drug Design , Drug Liberation , Glipizide/chemical synthesis , Hydrophobic and Hydrophilic Interactions , Delayed-Action Preparations/chemical synthesis , Delayed-Action Preparations/metabolism , Drug Carriers/metabolism , Drug Evaluation, Preclinical/methods , Glipizide/metabolism , Hydrogen-Ion Concentration , Polymers , Powders , Solubility , Tablets
7.
J Pharm Biomed Anal ; 139: 179-186, 2017 May 30.
Article in English | MEDLINE | ID: mdl-28284082

ABSTRACT

Cytochrome P450 (CYP) 2C9 and CYP2C19 genetic mutant could influence the plasma concentration of glipizide in human subjects, which refers to glipizide safety and adverse effects in clinic practice. A further study to investigate the relationship of the concentrations between glipizide and its metabolites in human with different CYP mutants was valuable. We firstly develop a validated liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for simultaneous quantification of glipizide and its hydroxylated metabolites in human urine. After simple protein precipitation with methanol including 4'-OH-tolbutamide and gliclazide (both are internal standards), the analytes were chromatographed on a reversed-phased column with a mobile phase of 0.1% formic acid in acetonitrile and 0.1% formic acid in water by a gradient elution. The ion transitions of the precursor to the product ion were principally protonated ions [M+H]+ at m/z 446.4→m/z 321.1 for glipizide, m/z 462.2→m/z 321.1 for the four hydroxylated forms of glipizide, m/z 287.2→m/z 188.0 for 4'-OH-tolbutamide, and m/z 324.1→m/z 127.1 for gliclazide. The method was linear over a concentration range of 0.02-20.0ng/mL. The intraday and inter-day variances were less than 9.9%, and accuracy was within ±6.8%. The method was successfully applied to the urinary phenotyping study in volunteers after a single oral administration of 5-mg glipizide tablet, and two new hydroxycyclohexyl metabolites of glipizide (OH-gp), 4-cis-OH-gp and 3-trans-OH-gp, were found in this study.


Subject(s)
Glipizide/urine , Phenotype , Tandem Mass Spectrometry/methods , Adult , Chromatography, Liquid/methods , Glipizide/metabolism , Humans , Hydroxylation , Male , Young Adult
8.
Int J Pharm ; 511(2): 957-68, 2016 Sep 25.
Article in English | MEDLINE | ID: mdl-27492020

ABSTRACT

Spray dried dispersions (SDDs) of glipizide, a BCS Class II model drug, were prepared using various grades of hydroxypropyl methylcellulose acetate succinate (HPMCAS) and copovidone S-630 as carriers. The SDDs appeared as a single amorphous phase with up to 60% drug loading level as revealed by X-ray powder diffraction (XRPD), modulated differential scanning calorimetry (mDSC) and scanning electron microscopy (SEM). Supersaturated micro-dissolution testing of various SDDs in fasted state simulated intestinal fluid showed prolonged supersaturation state (up to 180min) with solubility increases of 5.2-13.9 fold relative to crystalline drug under similar conditions. Solubility and stability characteristics of the most desirable SDDs in terms of relative dissolution AUCs (AUC(SDD)/AUC(crystalline)) and supersaturated concentration ratios (C180/Cmax) were determined. Results show that HPMCAS-based SDDs achieve a higher degree of supersaturation compared to Copovidone S-630 and that SDDs comprising HPMCAS-M and HPMCAS-H maintained stable supersaturated concentration. Dissolution data showed that SDD-loaded CR tablets provide stable supersaturated concentration within the hydrated matrix with increased rate and extent of drug dissolution over 24h. Co-existence of HPMCAS and HPMC within the hydrating matrix showed strong suppression of drug crystallization and allowed achievement of zero-order and slow-first order release kinetics.


Subject(s)
Chemistry, Pharmaceutical/methods , Glipizide/chemistry , Glipizide/metabolism , Delayed-Action Preparations/chemistry , Delayed-Action Preparations/metabolism , Solubility , X-Ray Diffraction
9.
Anal Bioanal Chem ; 407(18): 5309-21, 2015 Jul.
Article in English | MEDLINE | ID: mdl-25912461

ABSTRACT

In diabetes, the elevated levels of glucose in the bloodstream can result in the nonenzymatic glycation of proteins such as human serum albumin (HSA). This type of modification has been shown to affect the interactions of some drugs with HSA, including several sulfonylurea drugs that are used to treat type II diabetes. This study used high-performance affinity chromatography (HPAC) to examine the interactions of glipizide (i.e., a second-generation sulfonylurea drug) with normal HSA or HSA that contained various levels of in vitro glycation. Frontal analysis indicated that glipizide was interacting with both normal and glycated HSA through two general groups of sites: a set of relatively strong interactions and a set of weaker interactions with average association equilibrium constants at pH 7.4 and 37 °C in the range of 2.4-6.0 × 10(5) and 1.7-3.7 × 10(4) M(-1), respectively. Zonal elution competition studies revealed that glipizide was interacting at both Sudlow sites I and II, which were estimated to have affinities of 3.2-3.9 × 10(5) and 1.1-1.4 × 10(4) M(-1). Allosteric effects were also noted to occur for this drug between the tamoxifen site and the binding of R-warfarin at Sudlow site I. Up to an 18% decrease in the affinity for glipizide was observed at Sudlow site I ongoing from normal HSA to glycated HSA, while up to a 27% increase was noted at Sudlow site II. This information should be useful in indicating how HPAC can be used to investigate other drugs that have complex interactions with proteins. These results should also be valuable in providing a better understanding of how glycation may affect drug-protein interactions and the serum transport of drugs such as glipizide during diabetes.


Subject(s)
Glipizide/metabolism , Hypoglycemic Agents/metabolism , Serum Albumin/metabolism , Chromatography, Affinity/methods , Chromatography, High Pressure Liquid/methods , Diabetes Mellitus, Type 2/metabolism , Glycosylation , Humans , Protein Binding , Serum Albumin/chemistry
10.
J Photochem Photobiol B ; 142: 20-8, 2015 Jan.
Article in English | MEDLINE | ID: mdl-25490375

ABSTRACT

The complexity depicted by disease scenarios as diabetes mellitus, constitutes a very interesting field of study when drugs and biologically relevant components may be affected by such environments. In this report, the interaction between the protein Human Serum Albumin (HSA) and two antidiabetics (Andb), Gliclazide (Gli) and Glipizide (Glip) was studied through fluorescence and docking assays, in order to characterize these systems. On the basis that HSA and Andb can be exposed in vivo at high Reactive Oxygen Species (ROS) concentrations in diabetic patients, the degradative process of the protein free and bound to Andb, in presence of the species singlet molecular oxygen (O2((1)Δg)), was evaluated. Fluorescence and docking assays indicated that Gli, as well as Glip bind to HSA on two sites, with binding constants values in the order of 10(4)-10(5)M(-1). Likewise, docking assays revealed that the location of Gli or Glip on the protein may be the HSA binding sites II and III. Thermodynamic parameters showed that the interaction between HSA and Glip is a favored, enthalpically-controlled process. Oxygen uptake experiments indicated that Glip is less photooxidizable than Gli through a O2((1)Δg)-mediated process. Besides, the protein-Andb binding produced a decrease in the overall rate constant for O2((1)Δg) quenching as compared to the value for the free protein. This fact could be interpreted in terms of a reduction in the availability of Tyrosine residues in the bonded protein, with a concomitant decrease in the physical quenching deactivation of the oxidative species.


Subject(s)
Gliclazide/chemistry , Glipizide/chemistry , Hypoglycemic Agents/chemistry , Serum Albumin/chemistry , Singlet Oxygen/chemistry , Binding Sites , Gliclazide/metabolism , Glipizide/metabolism , Humans , Hypoglycemic Agents/metabolism , Light , Molecular Docking Simulation , Oxidation-Reduction , Protein Binding , Protein Structure, Tertiary , Reactive Oxygen Species/chemistry , Reactive Oxygen Species/metabolism , Serum Albumin/metabolism , Spectrometry, Fluorescence , Thermodynamics
11.
Ann Nucl Med ; 26(3): 253-61, 2012 Apr.
Article in English | MEDLINE | ID: mdl-22237676

ABSTRACT

OBJECTIVE: This study was aimed to assess pancreas beta cell activity using (99m)Tc-diethyleneaminepentaacetic acid-glipizide (DTPA-GLP), a sulfonylurea receptor agent. The effect of DTPA-GLP on the blood glucose level in rats was also evaluated. METHODS: DTPA dianhydride was conjugated with GLP in the presence of sodium amide, yielding 60%. Biodistribution and planar images were obtained at 30-120 min after injection of (99m)Tc-DTPA-GLP (1 mg/rat, 0.74 and 11.1 MBq per rat, respectively) in normal female Fischer 344 rats. The control group was given (99m)Tc-DTPA. To demonstrate pancreas beta cell uptake of (99m)Tc-DTPA-GLP via a receptor-mediated process, a group of rats was pretreated with streptozotocin (a beta cell toxin, 55 mg/kg, i.v.) and the images were acquired at immediately-65 min on day 5 post-treatment. The effect on the glucose levels after a single administration (ip) of DTPA-GLP was compared to glipizide (GLP) for up to 6 h. RESULTS: The structure of DTPA-GLP was confirmed by NMR, mass spectrometry and HPLC. Radiochemical purity assessed by ITLC was >96%. (99m)Tc-DTPA-GLP showed increased pancreas-to-muscle ratios, whereas (99m)Tc-DTPA showed decreased ratios at various time points. Pancreas could be visualized with (99m)Tc-DTPA-GLP in normal rat, however, (99m)Tc-DTPA has poor uptake suggesting the specificity of (99m)Tc-DTPA-GLP. Pancreas beta cell uptake could be blocked by pre-treatment with streptozotocin. DTPA-GLP showed an equal or better response in lowering the glucose levels compared to the existing GLP drug. CONCLUSIONS: It is feasible to use (99m)Tc-DTPA-GLP to assess pancreas beta cell receptor recognition. (99m)Tc-DTPA-GLP may be helpful in evaluating patients with diabetes, pancreatitis and pancreatic tumors.


Subject(s)
ATP-Binding Cassette Transporters/metabolism , Glipizide/chemistry , Glipizide/metabolism , Insulin-Secreting Cells/metabolism , Molecular Imaging/methods , Potassium Channels, Inwardly Rectifying/metabolism , Receptors, Drug/metabolism , Technetium Tc 99m Pentetate/chemistry , Animals , Blood Glucose/metabolism , Cell Size/drug effects , Chelating Agents/chemistry , Female , Glipizide/pharmacology , Insulin-Secreting Cells/cytology , Insulin-Secreting Cells/drug effects , Radiochemistry , Rats , Rats, Sprague-Dawley , Sulfonylurea Receptors , Technetium Tc 99m Pentetate/chemical synthesis , Technetium Tc 99m Pentetate/pharmacokinetics
12.
Eur J Pharmacol ; 623(1-3): 148-54, 2009 Nov 25.
Article in English | MEDLINE | ID: mdl-19765579

ABSTRACT

Inhibition of dipeptidyl peptidase-4 (DPP-4) activity has been shown to improve glycemic control in patients with type 2 diabetes by prolonging and potentiating the actions of incretin hormones. This study is designed to determine the effects of the DPP-4 inhibitor sitagliptin on improving islet function in a mouse model of insulin resistance and insulin secretion defects. ICR mice were pre-treated with high fat diet and a low dose of streptozotocin to induce insulin resistance and impaired insulin secretion, respectively. Diabetic mice were treated with sitagliptin or the sulfonylurea agent glipizide as admixture to high fat diet for ten weeks. Sustained reduction of blood glucose, HbA(1c), circulating glucagon and improvement in oral glucose tolerance were observed in mice treated with sitagliptin. In contrast, glipizide improved glycemic control only during the early weeks and to a lesser degree compared to sitagliptin, and had no effect on circulating glucagon levels or glucose tolerance. The improvement in glycemic control in sitagliptin-treated mice was associated with a significant increase in glucose-dependent insulin secretion in both perfused pancreas and isolated islets. Importantly, in contrast to the lack of effect by glipizide, sitagliptin significantly restored beta and alpha cell mass as well as alpha/beta cell ratio. These data indicate that DPP-4 inhibition by sitagliptin provided better overall improvement of glycemic control compared to glipizide in the high fat diet/streptozotocin induced diabetic mouse model. The ability of sitagliptin to enhance islet cell function may offer insight into the potential for disease modification.


Subject(s)
Blood Glucose/analysis , Diabetes Mellitus, Experimental/drug therapy , Diabetes Mellitus, Type 2/drug therapy , Dipeptidyl-Peptidase IV Inhibitors , Glipizide/therapeutic use , Hypoglycemic Agents/therapeutic use , Islets of Langerhans/drug effects , Pyrazines/therapeutic use , Triazoles/therapeutic use , Animals , Diabetes Mellitus, Experimental/physiopathology , Diabetes Mellitus, Type 2/physiopathology , Dietary Fats/administration & dosage , Dipeptidyl Peptidase 4 , Glipizide/metabolism , Glucagon/blood , Glucagon-Like Peptide 1/blood , Glycated Hemoglobin/analysis , Hypoglycemic Agents/metabolism , Insulin/blood , Insulin/metabolism , Insulin Secretion , Islets of Langerhans/metabolism , Islets of Langerhans/pathology , Ki-67 Antigen/metabolism , Lipids/blood , Liver/chemistry , Male , Mice , Mice, Inbred ICR , Organ Size , Pyrazines/metabolism , Sitagliptin Phosphate , Triazoles/metabolism , Triglycerides/analysis
13.
Am J Med ; 113(9): 746-50, 2002 Dec 15.
Article in English | MEDLINE | ID: mdl-12517365

ABSTRACT

Drug-metabolizing enzyme activity is one of many factors affecting patient response to medications. The objective of this review is to highlight the potential for genetic variability in cytochrome P450 enzyme activity that can lead to interperson differences in response to drugs. Awareness and application of this knowledge will improve drug use in clinical practice and provide the physician with further appreciation that standard drug dosing may not be appropriate in all patients.


Subject(s)
Cytochrome P-450 Enzyme System/metabolism , Anti-Arrhythmia Agents/metabolism , Antidepressive Agents, Tricyclic/metabolism , Aryl Hydrocarbon Hydroxylases/metabolism , Codeine/metabolism , Cytochrome P-450 CYP2C19 , Cytochrome P-450 CYP2C9 , Cytochrome P-450 CYP2D6/metabolism , Diazepam/metabolism , Genotype , Glipizide/metabolism , Humans , Mixed Function Oxygenases/metabolism , Omeprazole/metabolism , Pharmacogenetics , Phenotype , Phenytoin/metabolism , Warfarin/metabolism
14.
P R Health Sci J ; 20(1): 31-4, 2001 Mar.
Article in English | MEDLINE | ID: mdl-11394214

ABSTRACT

The objective of this research was to investigate the effects of hydrogen ion concentration, drug concentration and ionic strength on the binding affinity of glipizide to albumin protein. Different buffer solutions of different pH values (pH 6.7, 7.5 and 8.5), different drug concentrations (2.45 mg, 4.82 mg and 9.42 mg), and phosphate buffer solutions pH 7.5 of different ionic strength (0.1, 0.4 and 1.0) were prepared. The effects of pH, drug concentration and ionic strength on the amount of glipizide bounded to 0.25 g bovine albumin was investigated. As the pH of the solution was increased from pH 6.4 to pH 8.5, milligrams drug bounded to gram protein (r value) decreased from 8.2 mg to 3.84 mg/g protein. Also as the ionic strength of the solution was increased from 0.1 to 1.0, the r value decreased from 10.76 mg to 3.96 mg/g protein. However, the r value did not change significantly with increasing of drug from 2.45 mg to 9.42 mg/25 ml. The r value was 7.36 mg/g protein when concentration of the drug was 2.45 mg/25 ml and 7.4 mg/g protein when the concentration of the drug was 9.42 mg/25 ml. This study demonstrated that factors such as high pH and high ionic strength can alter drug-protein binding and consequently increase free drug in plasma and increase bioavailability of slightly water insoluble drug such as antidiabetic drugs.


Subject(s)
Glipizide/metabolism , Hypoglycemic Agents/metabolism , Serum Albumin, Bovine/metabolism , Dialysis , Dose-Response Relationship, Drug , Glipizide/chemistry , Hydrogen-Ion Concentration , Hypoglycemic Agents/chemistry , Time Factors
15.
In Vitr Mol Toxicol ; 13(1): 17-24, 2000.
Article in English | MEDLINE | ID: mdl-10900404

ABSTRACT

The phototoxic antidiabetes drug glipizide (1) is photolabile under aerobic conditions and UV-B light. Irradiation of a phosphate-buffered solution of 1 under oxygen atmosphere produces 4 photoproducts as well as singlet oxygen, which was detected by trapping it with 2,5-dimethylfuran and by the histidine test. The photochemistry of 1 involves cleavage of the sulfonamine and the sulfonamine-R bonds. Red blood cell lysis, photosensitized by glipizide and the products of its aerobic photolysis were demonstrated. The photohemolysis rate was lower for 1 than for its photoproducts. Inhibition of this process on addition of 1, 4-diazabicyclo[2.2.2]octane (DABCO), reduced glutathione (GSH), Vitamin C, sodium azide, superoxide dismutase, and a-tocopherol confirmed the possibility of singlet oxygen, superoxide ion and free radicals participation. Furthermore, in a lipid-photoperoxidation test with linoleic acid the in vitro phototoxicity of glipizide was also verified. A low decreasing cell viability of lymphocytes and neutrophils was observed.


Subject(s)
Glipizide/radiation effects , Glipizide/toxicity , Hypoglycemic Agents/radiation effects , Hypoglycemic Agents/toxicity , Oxygen/metabolism , Photolysis/radiation effects , Cell Survival/drug effects , Cell Survival/radiation effects , Cells, Cultured , Erythrocytes/cytology , Erythrocytes/drug effects , Erythrocytes/radiation effects , Free Radical Scavengers/pharmacology , Glipizide/metabolism , Hemolysis/drug effects , Hemolysis/radiation effects , Humans , Hypoglycemic Agents/metabolism , Kinetics , Linoleic Acid/metabolism , Lipid Peroxidation/drug effects , Lipid Peroxidation/radiation effects , Lymphocytes/cytology , Lymphocytes/drug effects , Lymphocytes/radiation effects , Neutrophils/cytology , Neutrophils/drug effects , Neutrophils/radiation effects , Oxygen/pharmacology , Oxygen/toxicity , Photosensitizing Agents/metabolism , Photosensitizing Agents/pharmacology , Photosensitizing Agents/toxicity , Radiation-Protective Agents/pharmacology , Reactive Oxygen Species/metabolism , Singlet Oxygen , Spectrophotometry , Ultraviolet Rays
16.
Biochem Biophys Res Commun ; 257(3): 766-70, 1999 Apr 21.
Article in English | MEDLINE | ID: mdl-10208857

ABSTRACT

The ATP-sensitive K+ channel, an octameric complex of two structurally unrelated types of subunits, SUR1 and Kir6.2, plays a central role in the physiological regulation of insulin secretion. The sulfonylurea glibenclamide, which trigger insulin secretion by blocking the ATP-sensitive K+ channel, interacts with both high and low affinity binding sites present on beta-cells. The high affinity binding site has been localized on SUR1 but the molecular nature of the low affinity site is still uncertain. In this study, we analyzed the pharmacology of glibenclamide in a transformed COS-7 cell line expressing the rat Kir6.2 cDNA and compared with that of the MIN6 beta cell line expressing natively both the Kir6.2 and the SUR1 subunits. Binding studies and Scatchard analysis revealed the presence of a single class of low affinity binding sites for glibenclamide on the COS/Kir6.2 cells with characteristics similar to that observed for the low affinity site of the MIN6 beta cells.


Subject(s)
ATP-Binding Cassette Transporters , Glyburide/metabolism , Islets of Langerhans/metabolism , Potassium Channels, Inwardly Rectifying , Potassium Channels/metabolism , Animals , Binding Sites , Blotting, Northern , COS Cells , Cell Line , Cell Membrane/drug effects , Cell Membrane/metabolism , Gliclazide/metabolism , Glipizide/metabolism , Glyburide/pharmacology , Islets of Langerhans/cytology , Kinetics , Organelles/metabolism , Phentolamine/metabolism , Potassium Channels/genetics , Rats , Receptors, Drug/genetics , Receptors, Drug/metabolism , Recombinant Fusion Proteins/genetics , Recombinant Fusion Proteins/metabolism , Sulfonylurea Compounds/metabolism , Sulfonylurea Receptors , Tolbutamide/metabolism , Transfection
17.
Probl Endokrinol (Mosk) ; 40(6): 47-50, 1994.
Article in Russian | MEDLINE | ID: mdl-7740038

ABSTRACT

Analysis of pancreatic beta-cell receptors binding the sulfanilamide drugs widely used in therapy of type II diabetes, such as glibenclamide, glipizide, and gliclazide, showed that these drugs are characterized by excellent parameters of specific binding to these receptors. The receptors were tested for two parameters: number of binding sites and dissociation constant. Glibenclamide was the most active of the drugs we tested, the other two agents being less active. Binding of these agents was reversible. The problem of identification of the examined receptors of sulfanilamides with K(+)-ATP-sensitive channels, similarly active conductors of the information transported by the sulfanilamide drugs in the mechanism of insulin secretion, is discussed.


Subject(s)
Islets of Langerhans/metabolism , Receptors, Drug/metabolism , Sulfanilamides/metabolism , Animals , Binding Sites , Gliclazide/metabolism , Glipizide/metabolism , Glyburide/metabolism , Male , Rats , Rats, Sprague-Dawley
18.
Folha méd ; 108(1/2): 39-41, jan.-fev. 1994. ilus, tab
Article in Portuguese | LILACS | ID: lil-154157

ABSTRACT

Foi realizado um estudo clínico objetivando o controle metabólico do diabetes mellitus nåo-insulino-dependente (NIDDM), utilizando-se um hipoglicemiante oral, glipizida (Minidiab), para o tratamento de 30 pacientes de ambos os sexos com idade entre 43 e 70 anos (57,4 mais ou menos 7,49) e portadores desta patologia, por um período de 4,97 mais ou menos 3,41 anos. Glipizina é uma sulfoniluréia de segunda geraçåo, que provou, através de estudos clínicos realizados, ser um medicamento seguro e eficaz, pois reduziu a valores aceitáveis os níveis de glicose de jejum, pós-prandial e triglicerídeos, em um período inicial de três meses de tratamento. Deste modo, reduziu o risco do distúrbio metabólico que caracteriza o diabetes mellitus nåo-insulino-dependente. Na decorrência do tratamento,, foram observadas reaçöes adversas leves como náuseas, tonteira, diarréia, as quais nåo obrigaram a interupçåo da medicaçåo. Foi constatado um caso de urticária, obrigando, portanto, à descontinuaçåo da medicaçåo neste paciente


Subject(s)
Humans , Male , Female , Adult , Middle Aged , Diabetes Mellitus, Type 2/drug therapy , Glipizide/metabolism , Blood Glucose/drug effects , Glipizide/pharmacokinetics , Glipizide/therapeutic use
19.
Clin Pharmacol Ther ; 49(1): 39-43, 1991 Jan.
Article in English | MEDLINE | ID: mdl-1988239

ABSTRACT

The effects of magnesium hydroxide on the pharmacokinetics and pharmacodynamics of glipizide were studied in eight healthy volunteers in a randomized crossover trial. After an overnight fast, 5 mg glipizide was given with either 150 ml water or water containing 850 mg magnesium hydroxide. Magnesium hydroxide increased the areas under the plasma glipizide concentration-time curves (AUC) from 0 to 1/2 hour and from 0 to 1 hour by 180% (p less than 0.05) and 69% (p less than 0.05), respectively. The peak plasma concentration, time to peak, total AUC, elimination half-life, and mean residence time of glipizide remained unchanged. The incremental plasma insulin area from 0 to 1/2 hour increased by 85% (p less than 0.05), and the time to maximal insulin response was reduced (p less than 0.05) during the magnesium hydroxide phase. The corresponding decremental plasma glucose area increased fourfold (p less than 0.05), and the maximal glucose decrease was 35% greater (p less than 0.05) than during the control phase. We conclude that the concomitant ingestion of magnesium hydroxide and glipizide may result in accelerated absorption of glipizide and increased early insulin and glucose responses.


Subject(s)
Glipizide/pharmacology , Magnesium Hydroxide/pharmacology , Adult , Blood Glucose/metabolism , Drug Interactions , Glipizide/metabolism , Humans , Insulin/metabolism , Intestinal Absorption/drug effects , Male
SELECTION OF CITATIONS
SEARCH DETAIL
...