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1.
RSC Adv ; 12(54): 34850-34873, 2022 Dec 06.
Article in English | MEDLINE | ID: mdl-36540224

ABSTRACT

In this study, combined DFT, SCAPS-1D, and wxAMPS frameworks are used to investigate the optimized designs of Cs2BiAgI6 double perovskite-based solar cells. First-principles calculations are employed to investigate the structural stability, optical responses, and electronic contribution of the constituent elements in Cs2BiAgI6 absorber material, where SCAPS-1D and wxAMPS simulators are used to scrutinize different configurations of Cs2BiAgI6 solar cells. Here, PCBM, ZnO, TiO2, C60, IGZO, SnO2, WS2, and CeO2 are used as ETL, and Cu2O, CuSCN, CuSbS2, NiO, P3HT, PEDOT:PSS, spiro-MeOTAD, CuI, CuO, V2O5, CBTS, CFTS are used as HTL, and Au is used as a back contact. About ninety-six combinations of Cs2BiAgI6-based solar cell structures are investigated, in which eight sets of solar cell structures are identified as the most efficient structures. Besides, holistic investigation on the effect of different factors such as the thickness of different layers, series and shunt resistances, temperature, capacitance, Mott-Schottky and generation-recombination rates, and J-V (current-voltage density) and QE (quantum efficiency) characteristics is performed. The results show CBTS as the best HTL for Cs2BiAgI6 with all eight ETLs used in this work, resulting in a power conversion efficiency (PCE) of 19.99%, 21.55%, 21.59%, 17.47%, 20.42%, 21.52%, 14.44%, 21.43% with PCBM, TiO2, ZnO, C60, IGZO, SnO2, CeO2, WS2, respectively. The proposed strategy may pave the way for further design optimization of lead-free double perovskite solar cells.

2.
Nanomaterials (Basel) ; 12(20)2022 Oct 13.
Article in English | MEDLINE | ID: mdl-36296771

ABSTRACT

In the future, when fossil fuels are exhausted, alternative energy sources will be essential for everyday needs. Hydrogen-based energy can play a vital role in this aspect. This energy is green, clean, and renewable. Electrochemical hydrogen devices have been used extensively in nuclear power plants to manage hydrogen-based renewable fuel. Doped zirconate materials are commonly used as an electrolyte in these electrochemical devices. These materials have excellent physical stability and high proton transport numbers, which make them suitable for multiple applications. Doping enhances the physical and electronic properties of zirconate materials and makes them ideal for practical applications. This review highlights the applications of zirconate-based proton-conducting materials in electrochemical cells, particularly in tritium monitors, tritium recovery, hydrogen sensors, and hydrogen pump systems. The central section of this review summarizes recent investigations and provides a comprehensive insight into the various doping schemes, experimental setup, instrumentation, optimum operating conditions, morphology, composition, and performance of zirconate electrolyte materials. In addition, different challenges that are hindering zirconate materials from achieving their full potential in electrochemical hydrogen devices are discussed. Finally, this paper lays out a few pathways for aspirants who wish to undertake research in this field.

3.
Pharmacol Res Perspect ; 8(4): e00565, 2020 08.
Article in English | MEDLINE | ID: mdl-32790160

ABSTRACT

Bruton's tyrosine kinase (BTK) plays a central and pivotal role in controlling the pathways involved in the pathobiology of cancer, rheumatoid arthritis (RA), and other autoimmune disorders. ZYBT1 is a potent, irreversible, specific BTK inhibitor that inhibits the ibrutinib-resistant C481S BTK with nanomolar potency. ZYBT1 is found to be a promising molecule to treat both cancer and RA. In the present report we profiled the molecule for in-vitro, in-vivo activity, and pharmacokinetic properties. ZYBT1 inhibits BTK and C481S BTK with an IC50 of 1 nmol/L and 14 nmol/L, respectively, inhibits the growth of various leukemic cell lines with IC50 of 1 nmol/L to 15 µmol/L, blocks the phosphorylation of BTK and PLCγ2, and inhibits secretion of TNF-α, IL-8 and IL-6. It has favorable pharmacokinetic properties suitable for using as an oral anti-cancer and anti-arthritic drug. In accordance with the in-vitro properties, it demonstrated robust efficacy in murine models of collagen-induced arthritis (CIA) and streptococcal cell wall (SCW) induced arthritis. In both models, ZYBT1 alone could suppress the progression of the diseases. It also reduced the growth of TMD8 xenograft tumor. The results suggested that ZYBT1 has high potential for treating RA, and cancer.


Subject(s)
Agammaglobulinaemia Tyrosine Kinase/antagonists & inhibitors , Protein Kinase Inhibitors/pharmacology , Animals , Arthritis, Experimental/drug therapy , Arthritis, Experimental/enzymology , Arthritis, Rheumatoid/drug therapy , Arthritis, Rheumatoid/enzymology , Humans , Inhibitory Concentration 50 , Mice , Neoplasms/drug therapy , Neoplasms/enzymology , Protein Kinase Inhibitors/administration & dosage , Protein Kinase Inhibitors/pharmacokinetics
4.
Bioorg Chem ; 99: 103851, 2020 06.
Article in English | MEDLINE | ID: mdl-32334196

ABSTRACT

Selective inhibition of janus kinase (JAK) has been identified as an important strategy for the treatment of autoimmune disorders. Optimization at the C2 and C4-positions of pyrimidine ring of Cerdulatinib led to the discovery of a potent and orally bioavailable 2,4-diaminopyrimidine-5-carboxamide based JAK3 selective inhibitor (11i). A cellular selectivity study further confirmed that 11i preferentially inhibits JAK3 over JAK1, in JAK/STAT signaling pathway. Compound 11i showed good anti-arthritic activity, which could be correlated with its improved oral bioavailability. In the repeat dose acute toxicity study, 11i showed no adverse changes related to gross pathology and clinical signs, indicating that the new class JAK3 selective inhibitor could be viable therapeutic option for the treatment of rheumatoid arthritis.


Subject(s)
Antirheumatic Agents/pharmacology , Arthritis, Experimental/drug therapy , Drug Discovery , Janus Kinase 3/antagonists & inhibitors , Protein Kinase Inhibitors/pharmacology , Pyrimidines/pharmacology , Animals , Antirheumatic Agents/chemical synthesis , Antirheumatic Agents/chemistry , Arthritis, Experimental/blood , Cell Line , Dose-Response Relationship, Drug , Humans , Janus Kinase 3/blood , Janus Kinase 3/metabolism , Male , Mice , Mice, Inbred C57BL , Mice, Inbred DBA , Molecular Docking Simulation , Molecular Structure , Protein Kinase Inhibitors/chemical synthesis , Protein Kinase Inhibitors/chemistry , Pyrimidines/chemical synthesis , Pyrimidines/chemistry , Rats , Structure-Activity Relationship
5.
Bioorg Med Chem Lett ; 29(11): 1313-1319, 2019 06 01.
Article in English | MEDLINE | ID: mdl-30975623

ABSTRACT

PI3Kδ is implicated in various inflammatory and autoimmune diseases. For the effective treatment of chronic immunological disorders such as rheumatoid arthritis, it is essential to develop isoform selective PI3Kδ inhibitors. Structure guided optimization of an imidazo-quinolinones based pan-PI3K/m-TOR inhibitor (Dactolisib) led to the discovery of a potent and orally bioavailable PI3Kδ isoform selective inhibitor (10h), with an improved efficacy in the animal models.


Subject(s)
Class I Phosphatidylinositol 3-Kinases/antagonists & inhibitors , Drug Discovery , Phosphoinositide-3 Kinase Inhibitors/pharmacology , Quinolones/pharmacology , Class I Phosphatidylinositol 3-Kinases/metabolism , Dose-Response Relationship, Drug , Humans , Molecular Structure , Phosphoinositide-3 Kinase Inhibitors/chemical synthesis , Phosphoinositide-3 Kinase Inhibitors/chemistry , Quinolones/chemical synthesis , Quinolones/chemistry , Structure-Activity Relationship
6.
Xenobiotica ; 49(10): 1164-1172, 2019 Oct.
Article in English | MEDLINE | ID: mdl-30488748

ABSTRACT

ZYTP1 is a novel Poly (ADP-ribose) polymerase protein inhibitor being developed for cancer indications. The focus of the work was to determine if ZYTP1 had a perpetrator role in the in vitro inhibition of cytochrome P450 (CYP) enzymes to aid dosing decisions during the clinical development of ZYTP1. ZYTP1 IC50 for CYP1A2, 2B6, 2C8, 2C9, 2C19, 2D6 and 3A4/5 was determined using human liver microsomes and LC-MS/MS detection. CYP3A4/5 IC50 of depropylated metabolite of ZYTP1 was also determined. Time dependent inhibition of CYP3A4/5 by ZYTP1 was also assessed using substrates, testosterone and midazolam. The mean IC50 values of ZYTP1 were >100 µM for CYP1A2, 2B6 and 2D6, while 56.1, 24.5, 39.5 and 23.3-58.7 µM for CYP2C8, 2C9, 2C19 and 3A4/5, respectively. The CYP3A4/5 IC50 of depropylated metabolite was 11.95-24.51 µM. Time dependent CYP3A4/5 inhibition was noted for testosterone and midazolam with IC50 shift of 10.9- and 39.9-fold, respectively. With midazolam, the kinact and KI values of ZYTP1 were 0.075 min-1 and 4.47 µM for the CYP3A4/5 time dependent inhibition, respectively. Because of potent inhibition of CYP3A4/5, drugs that undergo metabolism via CYP3A4/5 pathway should be avoided during ZYTP1 therapy.


Subject(s)
Cytochrome P-450 Enzyme Inhibitors , Cytochrome P-450 Enzyme System , Microsomes, Liver/enzymology , Poly(ADP-ribose) Polymerase Inhibitors , Cytochrome P-450 Enzyme Inhibitors/pharmacokinetics , Cytochrome P-450 Enzyme Inhibitors/pharmacology , Cytochrome P-450 Enzyme System/chemistry , Cytochrome P-450 Enzyme System/metabolism , Humans , Poly(ADP-ribose) Polymerase Inhibitors/pharmacokinetics , Poly(ADP-ribose) Polymerase Inhibitors/pharmacology
7.
J Med Chem ; 61(24): 10976-10995, 2018 12 27.
Article in English | MEDLINE | ID: mdl-30010338

ABSTRACT

The nuclear receptor retinoic acid receptor-related orphan receptor gamma (RORγ or RORc) is a key transcription factor for the production of pro-inflammatory cytokines implicated in the pathogenesis of autoimmune diseases. Recently, small molecule inhibitors of RORc drew the enormous attention of the research community worldwide as a possible therapy for autoimmune diseases, mediated by the IL-17 cytokine. With the clinical proof-of-concept inferred from a small molecule inhibitor VTP-43742 for psoriasis and recent inflow of several RORc inhibitors into the clinic for therapeutic interventions in autoimmune diseases, this field continues to evolve. This review briefly summarizes the RORc inhibitors disclosed in the literature and discusses the progress made by these inhibitors in combating autoimmune diseases.


Subject(s)
Autoimmune Diseases/drug therapy , Nuclear Receptor Subfamily 1, Group F, Member 3/antagonists & inhibitors , Sulfonamides/chemistry , Amides/chemistry , Amides/pharmacology , Clinical Trials as Topic , Humans , Nuclear Receptor Subfamily 1, Group F, Member 3/chemistry , Pyridines/chemistry , Pyridines/pharmacology , Pyrrolidines/chemistry , Pyrrolidines/pharmacology , Sulfonamides/pharmacology
8.
Cancer Chemother Pharmacol ; 82(4): 635-647, 2018 10.
Article in English | MEDLINE | ID: mdl-30046848

ABSTRACT

PURPOSE: Poly(ADP-ribose) polymerase-1 (PARP-1) is a nuclear enzyme involved in the detection and repair of DNA damage. Studies have shown that inhibition of PARP and Tankyrase (TNKS) has significant antitumor effect in several types of cancers including BRCA-negative breast cancers. METHODS: Identification of ZYTP1, a novel PARP inhibitor, through a battery of in vitro assays and in vivo studies. PARP and TNKS inhibitory activity of ZYTP1 was assessed in cell-free kinase assay. In vitro cell killing potency of ZYTP1 was tested in a panel of cell lines including BRCA-negative cells. ZYTP1 was also tested in xenograft models in combination with temozolomide (TMZ). The pharmacokinetic profile of ZYTP1 was determined in rodent and non-rodent preclinical species. Safety of ZYTP1 was assessed in Wistar rats and Beagle dogs upon repeated dosing. RESULTS: ZYTP1 inhibited PARP1, PARP2, Tankyrase-1 and Tankyrase-2 with IC50 of 5.4, 0.7, 133.3 and 289.8 nM, respectively, and additionally trapped PARP1 onto damaged DNA. It also potentiated MMS-mediated killing of different cancer cell lines. Compound demonstrated good Caco-2 cell permeability. The oral bioavailability of ZYTP1 in mice, rats and dogs ranged between 40 and 79% and demonstrated efficacy in colon cancer xenograft model at a dose of 1-10 mg/kg in combination with TMZ. In a 28-day repeat dosing, oral toxicity study in rats, it was found to show > 10× safety margin. CONCLUSIONS: ZYTP1 is a novel PARP inhibitor that showed potential for development as a treatment for various solid tumors.


Subject(s)
Breast Neoplasms/drug therapy , Colonic Neoplasms/drug therapy , Poly(ADP-ribose) Polymerase Inhibitors/pharmacology , Animals , Apoptosis/drug effects , Biological Availability , Cell Line, Tumor , Cell Proliferation/drug effects , DNA Damage/drug effects , Dogs , Drug Monitoring/methods , Humans , Mice , Poly(ADP-ribose) Polymerases/metabolism , Rats , Rats, Wistar , Tankyrases/antagonists & inhibitors , Treatment Outcome , Xenograft Model Antitumor Assays
9.
J Med Chem ; 61(16): 6964-6982, 2018 08 23.
Article in English | MEDLINE | ID: mdl-29712435

ABSTRACT

Chronic kidney disease, cancer, chronic inflammatory disorders, nutritional, and genetic deficiency can cause anemia. Hypoxia causes induction of hypoxia-inducible factor (HIF), which stimulates erythropoietin (EPO) synthesis. Prolyl hydroxylase domain (PHD) enzyme inhibition can stabilize hypoxia-inducible factor (HIF). HIF stabilization also decreases hepcidin, a hormone of hepatic origin, which regulates iron homeostasis. PHD inhibitors represent a novel pharmacological treatment of anemia associated with chronic diseases. Many orally active PHD inhibitors like roxadustat, molidustat, vadadustat, and desidustat are in late phase clinical trials. This review discusses the role of PHD inhibitors in the treatment of anemia associated with chronic diseases.


Subject(s)
Anemia/drug therapy , Genetic Diseases, Inborn/drug therapy , Inflammatory Bowel Diseases/drug therapy , Neoplasms/drug therapy , Prolyl-Hydroxylase Inhibitors/pharmacology , Renal Insufficiency, Chronic/drug therapy , Humans , Prolyl-Hydroxylase Inhibitors/chemistry
10.
Xenobiotica ; 48(1): 37-44, 2018 Jan.
Article in English | MEDLINE | ID: mdl-28042744

ABSTRACT

1. ZYAN1 is a prolyl hydroxylase inhibitor in clinical development for treatment of anemia associated with chronic kidney disease (CKD). We evaluated the effect of acute and chronic kidney impairment on the pharmacokinetics of ZYAN1 in rat models. 2. Cisplatin (2.5, 5 and 7.5 mg/kg) was used to induce acute kidney injury (AKI), and five-sixth and total nephrectomy was used to induce chronic kidney injury (CKI) in male Wistar rats. All groups received a single 15 mg/kg oral dose of ZYAN1. Blood/urine samples were analyzed for ZYAN1 to assess peak concentration (Cmax), area under the concentration-time curve (AUCinf), total body clearance (CL/F) and elimination half-life (T1/2). 3. Cmax and AUCinf were not significantly different in the various AKI groups or in five-sixth nephrectomized rats, as compared to control rats. Recovery of ZYAN1 in urine was reduced; the impact on the CL/F was minimal. There was a 2-fold increase in AUCinf with reduction in CL/F in total nephrectomized rats. T1/2 was longer for ZYAN1 in the severe AKI/five-sixth nephrectomy rats and total nephrectomy rats as compared to control rats. 4. Based on the rodent data it may be inferred that PK of ZYAN1 in CKD patients may be minimally affected.


Subject(s)
Kidney Failure, Chronic/metabolism , Quinolones/pharmacokinetics , Anemia/complications , Anemia/drug therapy , Animals , Male , Quinolones/therapeutic use , Rats , Rats, Wistar
11.
Bioanalysis ; 9(9): 719-732, 2017 May.
Article in English | MEDLINE | ID: mdl-28488896

ABSTRACT

AIM: A sensitive LC-MS/MS method was developed and validated for estimation of ZYAN1 in human blood/urine. METHODS: An analog internal standard IOX2 along with ZYAN1 was quantified using selective reaction monitoring in positive mode. The chromatographic separation was performed by gradient elution with C18 analytical column (3 µm, 50 mm × 2.0 mm) with 4-min run time using an acidified mobile phase consisting of ammonium formate and acetonitrile. Protein precipitation enabled extraction of analytes from diluted blood/urine. RESULTS: Calibration curve of ZYAN1 was linear (2-5000 ng/ml). The recovery of ZYAN1 and IOX2 was between 87 and 104%. Interday and intraday accuracy and precision was found well within the acceptance criteria. CONCLUSION: The validated assay was applied for clinical pharmacokinetics of ZYAN1 in healthy volunteers.


Subject(s)
Chromatography, High Pressure Liquid/methods , Prolyl-Hydroxylase Inhibitors/blood , Prolyl-Hydroxylase Inhibitors/urine , Quinolones/blood , Quinolones/urine , Tandem Mass Spectrometry/methods , Humans , Limit of Detection , Reproducibility of Results , Spectrometry, Mass, Electrospray Ionization/methods
12.
Br J Pharmacol ; 174(14): 2346-2357, 2017 Jul.
Article in English | MEDLINE | ID: mdl-28452143

ABSTRACT

BACKGROUND AND PURPOSE: Dipeptidyl peptidase (DPP)-4 inhibitors increase levels of glucagon-like peptide-1 (GLP-1) and provide clinical benefit in the treatment of type 2 diabetes mellitus. As longer acting inhibitors have therapeutic advantages, we developed a novel DPP-4 inhibitor, ZY15557, that has a sustained action and long half-life. EXPERIMENTAL APPROACH: We studied the potency, selectivity, efficacy and duration of action of ZY15557, in vitro, with assays of DPP-4 activity. In vivo, the pharmacodymamics and pharmacokinetics of ZY15557 were studied, using db/db mice and Zucker fatty rats, along with normal mice, rats, dogs and non-human primates. KEY RESULTS: ZY15557 is a potent, competitive and long acting inhibitor of DPP-4 (Ki 5.53 nM; Koff 3.2 × 10-4 ·s-1 , half-life 35.8 min). ZY15557 treatment inhibited DPP-4 activity, and enhanced active GLP-1 and insulin in mice and rats, providing dose-dependent anti-hyperglycaemic effects. Anti-hyperglycaemic effects were also observed in db/db mice and Zucker fatty rats. Following oral dosing, ZY15557 significantly inhibited plasma DPP-4 activity, determined ex vivo, in mice and rats for more than 48 h, and for up to 168 h in dogs and non-human primates. Allometric scaling predicts a half-life for ZY15557 in humans of up to 60 h. CONCLUSIONS AND IMPLICATIONS: ZY15557 is a potent, competitive and long acting DPP-4 inhibitor. ZY15557 showed similar DPP-4 inhibition across different species. ZY15557 showed excellent oral bioavailability in preclinical species. It showed a low plasma clearance (CL) and large volume of distribution (Vss ) across species, resulting in an extended half-life.


Subject(s)
Diabetes Mellitus, Experimental/drug therapy , Diabetes Mellitus, Type 2/drug therapy , Dipeptidyl Peptidase 4/metabolism , Dipeptidyl-Peptidase IV Inhibitors/pharmacology , Pyrans/pharmacology , Animals , Diabetes Mellitus, Experimental/metabolism , Diabetes Mellitus, Type 2/metabolism , Dipeptidyl-Peptidase IV Inhibitors/chemistry , Dogs , Dose-Response Relationship, Drug , Humans , Macaca mulatta , Male , Mice , Mice, Inbred C57BL , Mice, Obese , Molecular Structure , Pyrans/chemistry , Rats , Rats, Sprague-Dawley , Rats, Wistar , Rats, Zucker , Structure-Activity Relationship
13.
Drug Res (Stuttg) ; 67(4): 223-227, 2017 Apr.
Article in English | MEDLINE | ID: mdl-28158894

ABSTRACT

ZYDPLA1 is a long acting enzyme dipeptidyl peptidase-4 (DPP-4) inhibitor. The comparative effect of DPP-4 inhibition after intravenous (IV) and oral administration of ZYDPLA1 in a rat model was evaluated to answer the question of route dependency and/or the need of high plasma levels of ZYDPLA1. The study was conducted using parallel design in male Wistar rats for IV/oral route (n=9 and 6, for IV and oral respectively). A single 30 mg/kg dose of ZYDPLA1 was administered. Plasma samples were analysed for ZYDPLA1 concentration and DPP-4 inhibition. Pharmacokinetic analysis was carried out to assess peak concentration, area under the concentration-time curve, total body clearance, elimination half-life, and mean residence time. The PK/PD correlation was performed using standard sigmoidal Emax modelling to derive; maximum effect (Emax) and concentration to exert 50% Emax effect (EC50). ZYDPLA1 showed rapid absorption, high volume of distribution, low clearance, and complete oral bioavailability. The Emax derived after both routes and corresponding PK/PD profile showed comparable DDP-4 inhibition. The EC50 for IV (0.021 µg/mL) was comparable to the oral route (0.019 µg/mL). ZYDPLA1 showed full DPP-4 inhibition without regard to the route of administration. Higher systemic peak levels showed no bearing on the DDP-4 inhibition.


Subject(s)
Diabetes Mellitus, Experimental/drug therapy , Diabetes Mellitus, Type 2/drug therapy , Dipeptidyl Peptidase 4/metabolism , Dipeptidyl-Peptidase IV Inhibitors/administration & dosage , Dipeptidyl-Peptidase IV Inhibitors/pharmacokinetics , Hypoglycemic Agents/administration & dosage , Hypoglycemic Agents/pharmacokinetics , Administration, Intravenous , Administration, Oral , Animals , Area Under Curve , Biological Availability , Half-Life , Humans , Male , Rats , Rats, Wistar
14.
ACS Med Chem Lett ; 7(12): 1134-1138, 2016 Dec 08.
Article in English | MEDLINE | ID: mdl-27994752

ABSTRACT

GPR40/FFAR1 is a G protein-coupled receptor predominantly expressed in pancreatic ß-cells and activated by long-chain free fatty acids, mediating enhancement of glucose-stimulated insulin secretion. A novel series of substituted 3-(4-aryloxyaryl)propanoic acid derivatives were prepared and evaluated for their activities as GPR40 agonists, leading to the identification of compound 5, which is highly potent in in vitro assays and exhibits robust glucose lowering effects during an oral glucose tolerance test in nSTZ Wistar rat model of diabetes (ED50 = 0.8 mg/kg; ED90 = 3.1 mg/kg) with excellent pharmacokinetic profile, and devoid of cytochromes P450 isoform inhibitory activity.

15.
ACS Med Chem Lett ; 7(1): 51-5, 2016 Jan 14.
Article in English | MEDLINE | ID: mdl-26819665

ABSTRACT

TGR5 is a G protein-coupled receptor (GPCR), activation of which promotes secretion of glucagon-like peptide-1 (GLP-1) and modulates insulin secretion. The 2-thio-imidazole derivative 6g was identified as a novel, potent, and selective TGR5 agonist (hTGR5 EC50 = 57 pM, mTGR5 = 62 pM) with a favorable pharmacokinetic profile. The compound 6g was found to have potent glucose lowering effects in vivo during an oral glucose tolerance test in DIO C57 mice with ED50 of 7.9 mg/kg and ED90 of 29.2 mg/kg.

16.
J Diabetes ; 7(5): 708-17, 2015 Sep.
Article in English | MEDLINE | ID: mdl-25327540

ABSTRACT

OBJECTIVE: Dipeptidyl peptidase-4 (DPP-4) is responsible for degradation of glucagon-like peptide 1 (GLP-1) and gastric inhibitory polypeptide (GIP), the endogenous incretins that stimulate glucose-dependent insulin secretion. The objective was to evaluate preclinical profile of a novel DPP-4 inhibitor ZYDPLA1. METHODS: In vitro inhibition potency and selectivity were assessed using recombinant enzymes and/or plasma. In vivo efficacy was determined in oral glucose tolerance test or mixed meal tolerance test in C57BL/6J mice, db/db mice and Zucker fatty rats. Pharmacokinetics/pharmacodynamics was studied in mice, rats, dogs, and non-human primates. RESULTS: ZYDPLA1 is a potent, competitive and long acting inhibitor of DPP-4 (Ki 0.0027 µM; Koff 2.3 × 10(-4 ) s(-1) ). ZYDPLA1 was more than 7000-fold selective for recombinant DPP-4 relative to DPP-8 and DPP-9, and more than 60 000-fold selective relative to fibroblast activation protein (FAP) in vitro. DPP-4 inhibition was comparable across species. In vivo, oral ZYDPLA1 elevated circulating GLP-1 and insulin levels in mice and rats and showed dose-dependent anti-hyperglycemic effect. Anti-hyperglycemic effect was also observed in db/db mice and Zucker fatty rats. ZYDPLA1 showed low clearance, large volume of distribution, and a long half-life with excellent oral bioavailability in all species. It significantly inhibited plasma DPP-4 activity in mice and rats for more than 48 h, and for up to 168 h in dogs and non-human primates. Allometric scaling predicted a half-life in humans of 53 to 166 h. CONCLUSION: ZYDPLA1 is a potent, selective, long-acting oral DPP-4 inhibitor with potential to become once-a-week therapy for treatment of type 2 diabetes mellitus.


Subject(s)
Blood Glucose , Dipeptidyl-Peptidase IV Inhibitors/pharmacology , Hypoglycemic Agents/pharmacology , Animals , Dipeptidyl-Peptidase IV Inhibitors/pharmacokinetics , Dogs , Dose-Response Relationship, Drug , Glucagon-Like Peptide 1/blood , Hypoglycemic Agents/pharmacokinetics , Insulin/blood , Macaca mulatta , Male , Mice , Mice, Inbred C57BL , Rats , Rats, Zucker
17.
Br J Dermatol ; 167(1): 29-35, 2012 Jul.
Article in English | MEDLINE | ID: mdl-22348338

ABSTRACT

BACKGROUND: Leprosy is complicated by immunological reactions which can occur before, during and after successful completion of multidrug therapy. Genetic studies have suggested that polymorphisms in toll-like receptors (TLRs) may affect the susceptibility of an individual with leprosy to developing Type 1 reactions. OBJECTIVES: To examine the gene and protein expression of TLRs in the cutaneous lesions of leprosy Type 1 reactions at the onset of reaction and during systemic corticosteroid therapy. METHODS: Patients who were being treated for leprosy type 1 reactions with corticosteroids as part of a randomized controlled trial of corticosteroid treatment had skin biopsies performed before, during and at the end of treatment. The gene and protein expression of TLR2 and TLR4 were measured. RESULTS: We have demonstrated that the gene hARP-P0 is a suitable control gene for TLR gene expression studies in this population. The gene and protein expression of TLR2 and TLR4 were both reduced significantly during corticosteroid treatment. CONCLUSIONS: This is the first study to examine the expression of TLR2 and TLR4 in vivo in individuals experiencing leprosy Type 1 reactions. The data support the possibility of an important role for TLR2 and TLR4 in the pathogenesis of this important complication of leprosy.


Subject(s)
Glucocorticoids/therapeutic use , Leprosy/drug therapy , Toll-Like Receptor 2/physiology , Toll-Like Receptor 4/physiology , Adolescent , Adult , Analysis of Variance , Antibiotics, Antitubercular/therapeutic use , DNA, Complementary/biosynthesis , Drug Therapy, Combination , Female , Gene Expression , Humans , Immunohistochemistry , Leprosy/genetics , Leprosy/mortality , Male , Methylprednisolone/therapeutic use , Middle Aged , Prednisolone/therapeutic use , Toll-Like Receptor 2/drug effects , Toll-Like Receptor 2/genetics , Toll-Like Receptor 2/metabolism , Toll-Like Receptor 4/drug effects , Toll-Like Receptor 4/genetics , Toll-Like Receptor 4/metabolism , Young Adult
18.
Eur J Clin Pharmacol ; 65(10): 959-62, 2009 Oct.
Article in English | MEDLINE | ID: mdl-19707748

ABSTRACT

PURPOSE: We present a case of a patient who developed seizures shortly after initiating treatment with levofloxacin and to discuss the potential drug-drug interactions related to the inhibition of cytochrome P450 (CYP) 1A2 in this case, as well as in other cases, of levofloxacin-induced seizures. METHODS: Several biomedical databases were searched including MEDLINE, Cochrane and Ovid. The main search terms utilized were case report and levofloxacin. The search was limited to studies published in English. RESULTS: Six cases of levofloxacin-induced seizures have been reported in the literature. Drug-drug interactions related to the inhibition of CYP1A2 by levofloxacin are likely involved in the clinical outcome of these cases. CONCLUSIONS: Clinicians are exhorted to pay close attention when initiating levofloxacin therapy in patients taking medications with epileptogenic properties that are CYP1A2 substrates.


Subject(s)
Anti-Bacterial Agents/adverse effects , Bacteremia/microbiology , Klebsiella Infections/diagnosis , Levofloxacin , Ofloxacin/adverse effects , Seizures/chemically induced , Adrenergic alpha-Antagonists/adverse effects , Aged , Aged, 80 and over , Anti-Bacterial Agents/administration & dosage , Bacteremia/diagnosis , Cytochrome P-450 CYP1A2/drug effects , Cytochrome P-450 CYP1A2/metabolism , Dopamine Antagonists/adverse effects , Drug Administration Schedule , Drug Synergism , Female , Humans , Klebsiella Infections/drug therapy , Male , Metoclopramide/adverse effects , Mianserin/adverse effects , Mianserin/analogs & derivatives , Middle Aged , Mirtazapine , Ofloxacin/administration & dosage , Phosphodiesterase Inhibitors/adverse effects , Theophylline/adverse effects
19.
Nepal Med Coll J ; 10(1): 1-3, 2008 Mar.
Article in English | MEDLINE | ID: mdl-18700620

ABSTRACT

Phenolic glycolipid-I (PGL-I) is known to be a major antigen of Mycobacterium leprae. We have studied the influence of PGL-I on the production of Tumour Necrosis Factor alpha (TNF-alpha) using the in vitro whole blood assay. Armadillo-derived M. leprae (ADML) are thought to be depleted of PGL-I during the purification process. M. leprae obtained from mouse foot pad material (MFPML) has been subjected to a less rigorous purification process; their PGL-I coating is therefore believed to be more intact than that of ADML. PGL-I or ADML alone induced the secretion of minimal levels of TNF-alpha in whole blood assay; when added in combination, higher levels of this cytokine were observed. The highest TNF-alpha response was seen following stimulation with MFPML. MFP material not infected with ML did not elicit any response. The difference in TNF-alpha response shown by ADML and MFPML was postulated to be largely due to the presence of higher levels of PGL-I in MFPML. This increase in TNF-alpha production suggests that PGL-I may play a significant role in the induction of TNF-alpha during natural infection.


Subject(s)
Antigens, Bacterial/pharmacology , Blood Cells/metabolism , Glycolipids/pharmacology , Tumor Necrosis Factor-alpha/biosynthesis , Tumor Necrosis Factor-alpha/metabolism , Adolescent , Adult , Humans , Leprosy/metabolism , Male , Mycobacterium leprae
20.
Bioorg Med Chem Lett ; 16(6): 1673-8, 2006 Mar 15.
Article in English | MEDLINE | ID: mdl-16384704

ABSTRACT

Beginning with a moderately potent PPARgamma agonist 9, a series of potent and highly subtype-selective PPARalpha agonists was identified through a systematic SAR study. Based on the results of the efficacy studies in the hamster and dog models of dyslipidemia and the desired pharmacokinetic data, the optimized compound 39 was selected for further profiling.


Subject(s)
Drug Design , Dyslipidemias/drug therapy , Hypolipidemic Agents/chemical synthesis , PPAR alpha/agonists , Animals , Cricetinae , Dogs , Haplorhini , Hypolipidemic Agents/pharmacokinetics , Hypolipidemic Agents/pharmacology , Molecular Structure , PPAR alpha/genetics , Rats , Structure-Activity Relationship , Transcriptional Activation
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