Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 83
Filter
Add more filters

Publication year range
1.
Toxicol Appl Pharmacol ; 483: 116832, 2024 02.
Article in English | MEDLINE | ID: mdl-38266872

ABSTRACT

Iron deficiency anemia is caused by many pathological conditions like chronic kidney disease (CKD), inflammation, malnutrition and gastrointestinal abnormality. Current treatments that are erythropoiesis stimulating agents (ESAs) and iron supplementation are inadequate and often lead to tolerance and/or toxicity. Desidustat, a prolyl hydroxylase (PHD) inhibitor, is clinically used for the treatment of anemia with CKD. In this study, we investigated the effect of desidustat on iron deficiency anemia (IDA). IDA was induced in C57BL6/J mice by iron deficient diet feeding. These mice were then treated with desidustat (15 mg/kg, PO) and FeSO4 (20 mg/kg) for five weeks and effect of the treatment on hematology, iron homeostasis, and bone marrow histology was observed. Effect of desidustat on iron metabolism in inflammation (LPS)-induced iron deficiency was also assessed. Both, Desidustat and FeSO4, increased MCV (mean corpuscular volume), MCH (mean corpuscular hemoglobin), hemoglobin, and HCT (hematocrit) in blood and increased iron in serum, liver, and spleen. Desidustat increased MCHC (mean corpuscular hemoglobin concentration) while FeSO4 treatment did not alter it. FeSO4 treatment significantly increased iron deposition in liver, and spleen, while desidustat increased iron in circulation and demonstrated efficient iron utilization. Desidustat increased iron absorption, serum iron and decreased hepcidin without altering tissue iron, while FeSO4 increased serum and tissue iron by increasing hepcidin in LPS-induced iron deficiency. Desidustat increased erythroid population, especially iron-dependent polychromatic normoblasts and orthochromatic normoblasts, while FeSO4 did not improve cell architecture. PHD inhibition by desidustat improved iron utilization in iron deficiency anemia, by efficient erythropoiesis.


Subject(s)
Anemia, Iron-Deficiency , Prolyl-Hydroxylase Inhibitors , Quinolones , Renal Insufficiency, Chronic , Mice , Animals , Anemia, Iron-Deficiency/drug therapy , Hepcidins/metabolism , Prolyl-Hydroxylase Inhibitors/pharmacology , Prolyl-Hydroxylase Inhibitors/therapeutic use , Lipopolysaccharides , Iron/metabolism , Inflammation/metabolism , Hemoglobins/analysis
2.
Int J Toxicol ; : 10915818241261922, 2024 Jun 20.
Article in English | MEDLINE | ID: mdl-38901831

ABSTRACT

These toxicity studies aimed to assess the safety and tolerability of a novel intravenous diclofenac sodium (37.5 mg/mL) formulation containing povidone K12 (80 mg/mL) as the key excipient in Wistar rats. This formulation was tested at doses of 3, 7, and 15 mg/kg/day and was administered daily for 28 days by intravenous route. Toxicokinetic estimation revealed a dose-proportional increase in plasma exposure to diclofenac. The formulation was well tolerated in males; however, mortality was observed in females (2/15) at the highest dose (15 mg/kg/day). Adverse gastrointestinal events related to NSAIDS and a few other treatment-related effects on clinical and anatomic pathology were noted at the 15 mg/kg/day dose, which normalized at the end of the 2-week recovery period. In addition, the excipient povidone K12 was present in a higher amount than the approved Inactive Ingredient Database (IID) limit in the proposed novel formulation. It was qualified through a separate 28-day repeated dose toxicity study by intravenous route in Wistar rats. Povidone K12 was found to be well tolerated and safe up to a dose of 165 mg/kg/day. No treatment-related adverse effects were observed in this study. In conclusion, repeated administration of a novel intravenous formulation containing diclofenac sodium was found to be safe up to the dose of 7 mg/kg/day in female rats and 15 mg/kg/day in male rats.

3.
Int J Toxicol ; 43(2): 184-195, 2024.
Article in English | MEDLINE | ID: mdl-38108647

ABSTRACT

Electrocardiographic evaluation is performed in rhesus monkeys to establish the cardiovascular safety of candidate molecules before progressing to clinical trials. These animals are usually immobilized chemically by ketamine (KTM) and tiletamine-zolazepam (TZ) to obtain a steady-state heart rate and to ensure adequate human safety. The present study aimed to evaluate the effect of these anesthetic regimens on different electrocardiographic parameters. Statistically significant lower HR and higher P-wave duration, RR, QRS, and QT intervals were observed in the KTM-anesthetized group in comparison to TZ-anesthetized animals. No significant changes were noticed in the PR interval and p-wave amplitude. Sex-based significance amongst these parameters was observed in male and female animals of TZ- and KTM-anesthetized groups. Regression analysis of four QTc formulas in TZ-anesthetized rhesus monkeys revealed that QTcNAK (Nakayama) better corrected the QT interval than QTcHAS (Hassimoto), QTcBZT (Bazett), and QTcFRD (Fridericia) formulas. QTcNAK exhibited the least correlation with the RR interval (slope closest to zero and r = .01) and displayed no statistical significance between male and female animals. These data will prove useful in the selection of anesthetic regimens for chemical restraint of rhesus monkeys in nonclinical safety evaluation studies.


Subject(s)
Anesthetics , Ketamine , Animals , Humans , Male , Female , Ketamine/toxicity , Tiletamine/toxicity , Macaca mulatta , Zolazepam/toxicity , Retrospective Studies , Anesthetics/toxicity , Heart Rate
4.
BMC Cancer ; 23(1): 59, 2023 Jan 17.
Article in English | MEDLINE | ID: mdl-36650455

ABSTRACT

BACKGROUND: Saroglitazar is a novel PPAR-α/γ agonist with predominant PPAR-α activity. In various preclinical models, saroglitazar has been shown to prevent & reverse symptoms of NASH. In view of these observations, and the fact that NASH is a progressive disease leading to HCC, we hypothesized that saroglitazar may prevent the development of HCC in rodents. METHODS: HCC was induced in C57BL/6 mice by a single intraperitoneal injection of 25 mg/kg diethylnitrosamine (DEN) at the age of 4 weeks and then feeding the animal a choline-deficient, L-amino acid- defined, high-fat diet (CDAHFD) for the entire study duration. Eight weeks after initiation of CDAHFD, saroglitazar (1 and 3 mg/kg) treatment was started and continued for another 27 weeks. RESULTS: Saroglitazar treatment significantly reduced the liver injury markers (serum ALT and AST), reversed hepatic steatosis and decreased the levels of pro-inflammatory cytokines like TNF-α in liver. It also resulted in a marked increase in serum adiponectin and osteopontin levels. All disease control animals showed hepatic tumors, which was absent in saroglitazar (3 mg/kg)- treatment group indicating 100% prevention of hepatic tumorigenesis. This is the first study demonstrating a potent PPARα agonist causing suppression of liver tumors in rodents, perhaps due to a strong anti-NASH activity of Saroglitazar that overrides its rodent-specific peroxisome proliferation activity. CONCLUSION: The data reveals potential of saroglitazar for chemoprevention of hepatocellular carcinoma in patients with NAFLD/NASH.


Subject(s)
Carcinoma, Hepatocellular , Liver Neoplasms , Non-alcoholic Fatty Liver Disease , Mice , Animals , Carcinoma, Hepatocellular/chemically induced , Carcinoma, Hepatocellular/drug therapy , Carcinoma, Hepatocellular/prevention & control , Choline , Diethylnitrosamine/toxicity , Liver Neoplasms/chemically induced , Liver Neoplasms/drug therapy , Liver Neoplasms/prevention & control , Injections, Intraperitoneal , Diet, High-Fat/adverse effects , Amino Acids , Peroxisome Proliferator-Activated Receptors , Mice, Inbred C57BL , Liver/pathology , Non-alcoholic Fatty Liver Disease/etiology , Disease Models, Animal
5.
Toxicol Mech Methods ; 33(6): 490-501, 2023 Nov.
Article in English | MEDLINE | ID: mdl-36879461

ABSTRACT

Rhesus monkeys are a non-rodent species employed in the preclinical safety evaluation of pharmaceuticals and biologics. These nonhuman primate species have been increasingly used in biomedical research because of the similarity in their ionic mechanisms of repolarization with humans. Heart rate and QT interval are two primary endpoints in determining the pro-arrhythmic risk of drugs. As heart rate and QT interval have an inverse relationship, any change in heart rate causes a subsequent change in QT interval. This warrants for calculation of a corrected QT interval. This study aimed to identify an appropriate formula that best corrected QT for change in heart rate. We employed seven formulas based on source-species type, clinical relevance, and requirements of various international regulatory guidelines. Data showed that corrected QT interval values varied drastically for different correction formulas. Equations were compared on their slope values based on QTc versus RR plots. The rank order of the slope for different formulas was (closest to farthest from zero) QTcNAK, QTcHAS, QTcBZT, QTcFRD, QTcVDW, QTcHDG, and QTcFRM. QTcNAK emerged to be the best correcting formula in this study. It showed the least correlation with the RR interval (r = -0.01) and displayed no significant difference amongst the sexes. As there is no universally recognized formula for preclinical use, the authors recommend developing a best-case scenario model for specific study designs and individual organizations. The data from this research will be helpful in deciding an appropriate QT correction formula for the safety assessment of new pharmaceuticals and biologics.


Subject(s)
Ketamine , Long QT Syndrome , Animals , Humans , Electrocardiography , Macaca mulatta , Ketamine/toxicity , Heart Rate , Pharmaceutical Preparations , Long QT Syndrome/chemically induced
6.
Bioorg Med Chem ; 35: 116071, 2021 04 01.
Article in English | MEDLINE | ID: mdl-33611013

ABSTRACT

The ever-growing prevalence of Type-2 diabetes in the world has an urgent need for multiple orally effective agents that can regulate glucose homeostasis. G-Protein coupled receptor 119 (GPR 119) agonists have demonstrated the glucose-dependent insulin secretion and showed beneficial effects on glycemic control in humans and/or relevant animal models. Herein, we describe our efforts towards identification of a potent and oral GPR 119 agonist 13c (ZY-G19), which showed in vitro potency in the cell-based assay and in vivo efficacy without exerting any significant signs of toxicity in relevant animal models.


Subject(s)
Diabetes Mellitus, Type 2/drug therapy , Drug Discovery , Hypoglycemic Agents/pharmacology , Receptors, G-Protein-Coupled/agonists , Animals , Diabetes Mellitus, Type 2/metabolism , Dose-Response Relationship, Drug , Female , Glucose Tolerance Test , Humans , Hypoglycemic Agents/chemistry , Male , Mice , Mice, Inbred C57BL , Molecular Structure , Rats , Rats, Wistar , Receptors, G-Protein-Coupled/metabolism , Structure-Activity Relationship
7.
Biomed Chromatogr ; 35(2): e4981, 2021 Feb.
Article in English | MEDLINE | ID: mdl-32895916

ABSTRACT

An LC-tandem mass spectrometry method was developed and validated for the simultaneous quantitation of fimasartan and sacubitrilat using positive ion mode. The protein precipitation method was employed for the extraction of fimasartan, sacubitrilat and alprazolam (internal standard) from rat heparinized plasma. Baseline separation of the analytes was accomplished using an ACE-5, C18 (4.6 × 50 mm) column and gradient elution of mobile phase A (5 mm ammonium formate and 0.1% formic acid in purified water) and B (acetonitrile:methanol, 80:20; v/v). All peaks of interest were eluted within a 5-min runtime. The quantitation was achieved in the selected reaction monitoring mode. The developed method was validated as per US Food and Drug Administration guidelines and met the pre-defined acceptance criteria. The method showed linearity from 5 to 10,000 ng/mL. The accuracy/precision of intra- and inter-batch assays was 96.64%/2.05% to 109.17%/13.70% and 100.74%/3.76% to 106.39%/9.75% for fimasartan and 100.02%/1.49% to 113.80%/9.38% and 100.75%/2.31% to 108.40%/7.74% for sacubitrilat, respectively, in rat plasma. Fimasartan and sacubitrilat remained stable in rat plasma at different experimental conditions up to 21 days. The developed method was sensitive, selective and applied successfully to monitor plasma concentrations of fimasartan and sacubitrilat in an oral rat pharmacokinetic study.


Subject(s)
Aminobutyrates/blood , Biphenyl Compounds/blood , Chromatography, Liquid/methods , Pyrimidines/blood , Tandem Mass Spectrometry/methods , Tetrazoles/blood , Aminobutyrates/chemistry , Aminobutyrates/pharmacokinetics , Animals , Biphenyl Compounds/chemistry , Biphenyl Compounds/pharmacokinetics , Linear Models , Male , Prodrugs , Pyrimidines/chemistry , Pyrimidines/pharmacokinetics , Rats , Rats, Sprague-Dawley , Rats, Wistar , Reproducibility of Results , Sensitivity and Specificity , Spectrometry, Mass, Electrospray Ionization/methods , Tetrazoles/chemistry , Tetrazoles/pharmacokinetics
8.
Drug Dev Res ; 82(6): 852-860, 2021 09.
Article in English | MEDLINE | ID: mdl-33480036

ABSTRACT

Chronic kidney disease (CKD) is associated with activated inflammatory responses. Desidustat, a prolyl hydroxylase (PHD) inhibitor is useful for treatment of anemia associated with CKD, but its effect on the inflammatory and fibrotic changes in CKD is not evaluated. In this study, we investigated the effect of desidustat on the inflammatory and fibrotic changes in preclinical models of acute and chronic kidney injury. Acute kidney injury was induced in male Sprague Dawley rats by ischemia-reperfusion, in which effect of desidustat (15 mg/kg, PO) was estimated. In a separate experiment, male C57 mice were treated with adenine for 14 days to induce CKD. These mice were treated with desidustat (15 mg/kg, PO, alternate day) treatment for 14 days, with adenine continued. Desidustat prevented elevation of serum creatinine, urea, IL-1ß, IL-6, and kidney injury molecule-1 (KIM-1), and elevated the erythropoietin levels in rats that were subjected to acute kidney injury. Mice treated with adenine developed CKD and anemia, and desidustat treatment caused improvement in serum creatinine, urea, and also improved hemoglobin and reduced hepatic and serum hepcidin. A significant reduction in IL-1ß, IL-6, myeloperoxidase (MPO) and oxidative stress was observed by desidustat treatment. Desidustat treatment also reduced renal fibrosis as observed by histological analysis and hydroxyproline content. Desidustat treatment reduced the renal fibrosis and inflammation along with a reduction in anemia in preclinical models of kidney injury, which may translate to protective effects in CKD patients.


Subject(s)
Prolyl-Hydroxylase Inhibitors , Quinolones , Reperfusion Injury , Animals , Cytokines/metabolism , Kidney , Male , Mice , Mice, Inbred C57BL , Oxidative Stress , Prolyl-Hydroxylase Inhibitors/pharmacology , Quinolones/pharmacology , Rats , Rats, Sprague-Dawley , Reperfusion Injury/pathology
9.
Bioorg Med Chem Lett ; 30(21): 127571, 2020 11 01.
Article in English | MEDLINE | ID: mdl-32980515

ABSTRACT

NLRP3 inflammasome mediated release of interleukin-1ß (IL-1ß) has been implicated in various diseases, including COVID-19. In this study, rationally designed alkenyl sulfonylurea derivatives were identified as novel, potent and orally bioavailable NLRP3 inhibitors. Compound 7 was found to be potent (IL-1ß IC50 = 35 nM; IL-18 IC50 = 33 nM) and selective NLRP3 inflammasome inhibitor with excellent pharmacokinetic profile having oral bioavailability of 99% in mice.


Subject(s)
Inflammasomes/antagonists & inhibitors , NLR Family, Pyrin Domain-Containing 3 Protein/antagonists & inhibitors , Sulfonylurea Compounds/pharmacology , Administration, Oral , Animals , Betacoronavirus , COVID-19 , Cell Line, Tumor , Coronavirus Infections , Cytochrome P-450 CYP2C8 Inhibitors/administration & dosage , Cytochrome P-450 CYP2C8 Inhibitors/chemical synthesis , Cytochrome P-450 CYP2C8 Inhibitors/pharmacokinetics , Cytochrome P-450 CYP2C8 Inhibitors/pharmacology , Cytochrome P-450 CYP2C9 Inhibitors/administration & dosage , Cytochrome P-450 CYP2C9 Inhibitors/chemical synthesis , Cytochrome P-450 CYP2C9 Inhibitors/pharmacokinetics , Cytochrome P-450 CYP2C9 Inhibitors/pharmacology , Dogs , Drug Stability , Humans , Interleukin-1beta/antagonists & inhibitors , Mice, Inbred C57BL , Microsomes, Liver/metabolism , Molecular Structure , Pandemics , Pneumonia, Viral , Rats , SARS-CoV-2 , Structure-Activity Relationship , Sulfonylurea Compounds/administration & dosage , Sulfonylurea Compounds/chemical synthesis , Sulfonylurea Compounds/pharmacokinetics
10.
Xenobiotica ; 50(7): 815-821, 2020 Jul.
Article in English | MEDLINE | ID: mdl-31755347

ABSTRACT

Recent approvals of beta-lactamase inhibitor (BLI) drug in combination with cephalosporins/penems have provided the right impetus for novel BLIs. One important research question, hitherto not addressed, is pertaining to the relevance of preclinical pharmacokinetics for pairing the antibiotic with existing/novel BLI.Two BLI combination drugs: (a) approved (i.e. ceftazidime/avibactam); (b) clinical development (i.e. cefepime/zidebactam) were explored to provide insights to address the research question.Individual intravenous dosing of ceftazidime, avibactam, cefepime and zidebactam was done at 1 mg/kg by intravenous route in Balb/c mice and Wistar rats. Serial blood samples were collected and analysed by LC-MS/MS method.Examination of the ratios of pharmacokinetic parameters (CL, VSS and T1/2) for individual drugs in combinations (for instance, CL (ceftazidime)/CL (avibactam); CL (cefepime)/CL (zidebactam)) suggested that the pharmacokinetic data gathered in rats were generally within 0.5- to 2-fold; but mouse data revealed larger disparity for VSS (0.11- to 8.25-fold) or CL (0.49- to 4.03-fold).The observed ratio for CL/VSS observed in rats agreed with corresponding human ratios for the pairwise comparison of the individual drugs in the combinations.Retrospectively, current pharmacokinetic findings suggest rat pharmacokinetic data may aid the combination of BLI with an appropriate antibiotic.


Subject(s)
Azabicyclo Compounds/metabolism , Ceftazidime/metabolism , beta-Lactamase Inhibitors/metabolism , Animals , Cyclooctanes , Drug Combinations , Mice , Microbial Sensitivity Tests , Piperidines , Rats , Rodentia
11.
Liver Int ; 38(6): 1084-1094, 2018 06.
Article in English | MEDLINE | ID: mdl-29164820

ABSTRACT

BACKGROUND & AIMS: Non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steatohepatitis (NASH) are common clinico-pathological conditions that affect millions of patients worldwide. In this study, the efficacy of saroglitazar, a novel PPARα/γ agonist, was assessed in models of NAFLD/NASH. METHODS & RESULTS: HepG2 cells treated with palmitic acid (PA;0.75 mM) showed decreased expression of various antioxidant biomarkers (SOD1, SOD2, glutathione peroxidase and catalase) and increased expression of inflammatory markers (TNFα, IL1ß and IL6). These effects were blocked by saroglitazar, pioglitazone and fenofibrate (all tested at 10µM concentration). Furthermore, these agents reversed PA-mediated changes in mitochondrial dysfunction, ATP production, NFkB phosphorylation and stellate cell activation in HepG2 and HepG2-LX2 Coculture studies. In mice with choline-deficient high-fat diet-induced NASH, saroglitazar reduced hepatic steatosis, inflammation, ballooning and prevented development of fibrosis. It also reduced serum alanine aminotransferase, aspartate aminotransferase and expression of inflammatory and fibrosis biomarkers. In this model, the reduction in the overall NAFLD activity score by saroglitazar (3 mg/kg) was significantly more prominent than pioglitazone (25 mg/kg) and fenofibrate (100 mg/kg). Pioglitazone and fenofibrate did not show any improvement in steatosis, but partially improved inflammation and liver function. Antifibrotic effect of saroglitazar (4 mg/kg) was also observed in carbon tetrachloride-induced fibrosis model. CONCLUSIONS: Saroglitazar, a dual PPARα/γ agonist with predominant PPARα activity, shows an overall improvement in NASH. The effects of saroglitazar appear better than pure PPARα agonist, fenofibrate and PPARγ agonist pioglitazone.


Subject(s)
Biomarkers/blood , Liver/pathology , Non-alcoholic Fatty Liver Disease/drug therapy , PPAR alpha/agonists , Phenylpropionates/pharmacology , Pyrroles/pharmacology , Alanine Transaminase/blood , Animals , Aspartate Aminotransferases/blood , Diet, High-Fat , Fenofibrate/pharmacokinetics , Hep G2 Cells , Humans , Kupffer Cells/drug effects , Male , Mice , Mice, Inbred C57BL , Non-alcoholic Fatty Liver Disease/pathology , Pioglitazone/pharmacology , Tumor Necrosis Factor-alpha/blood
12.
Xenobiotica ; 48(12): 1268-1277, 2018 Dec.
Article in English | MEDLINE | ID: mdl-29224415

ABSTRACT

1. Saroglitazar, a novel peroxisome proliferator-activated receptor (PPAR) agonist, regulates lipid and glucose metabolism. The objective of this report is to provide a preclinical evaluation (in vitro/in vivo) of ADME properties of saroglitazar. In vitro studies included determination of permeability, metabolic stability, plasma protein binding, CYP reaction phenotyping and CYP inhibitory liability. In vivo studies included oral bioavailability and pharmacokinetic assessment in mouse, rat and dog. The excretion of saroglitazar was determined in rats. Exploratory metabolism of saroglitazar was evaluated using in vitro and in vivo samples. 2. Saroglitazar was metabolically more stable in human liver microsomes as compared to rat and dog liver microsomes, highly protein bound (98-99.6%) with high Caco2 permeability (104 nm/s) with <2 efflux ratio. In vitro metabolism in rat, dog and human liver microsomes revealed three putative metabolites corresponding to di-hydroxylation, mono-oxygenation and dehydrogenation moieties. 3. Oral bioavailability was 100%, 72% and 47% in mouse, rat and dog, respectively. The intravenous clearance and volume of distribution of saroglitazar were 3.6, 8.5 and 6.9 mL/min/kg and 1.3, 4.8 and 1.8 L/kg for mouse, rat and dog, respectively. The elimination half-life of saroglitazar ranged between 6 and 15 h. Saroglitazar appeared to be eliminated via hepatobiliary route with negligible renal excretion.


Subject(s)
Dyslipidemias , Microsomes, Liver/metabolism , PPAR alpha/agonists , PPAR gamma/agonists , Phenylpropionates , Pyrroles , Animals , Caco-2 Cells , Dogs , Drug Evaluation, Preclinical , Dyslipidemias/drug therapy , Dyslipidemias/metabolism , Dyslipidemias/pathology , Humans , Mice , Phenylpropionates/pharmacokinetics , Phenylpropionates/pharmacology , Pyrroles/pharmacokinetics , Pyrroles/pharmacology , Rats
13.
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
14.
Can J Physiol Pharmacol ; 94(2): 161-167, 2016 Feb.
Article in English | MEDLINE | ID: mdl-26629909

ABSTRACT

Glucagon-like peptide-1 (GLP-1) receptor agonists modulate lipid metabolism, apart from controlling glucose homeostasis. We investigated the role of central GLP-1 receptor (GLP-1R) agonism in regulation of hepatic lipid metabolism in cholesterol-fed hamsters. Cholesterol-fed hamsters were treated by intracerebroventricular (i.c.v.) route with exendin-4, as acute or repeated dose regimen and compared with hamsters pair-fed to the exendin-treated hamsters and with hamsters co-treated with GLP-1 antagonist exendin-9. Effect of acute treatment was observed on food intake, tyloxapol-induced hypertriglyceridemia, and corn oil induced post prandial lipemia. Plasma and hepatic lipids and changes in the expression of hepatic genes involved in lipid metabolism were assessed after chronic administration. Acute, as well as repeated dose, treatment of exendin-4 showed significant changes in hepatic lipids, circulating fatty acids, triglycerides, LDL, and cholesterol. Expression of SREBP-1c was reduced while that of LDLR and CYP7A1 was increased after the repeated dose treatment, and there was no change in HMG CoA reductase. These changes were blocked by co-treatment of exendin-9, and not replicated by pair feeding to the significant extent. Central GLP-1 receptor activation showed profound effects on peripheral lipid metabolism, which were partially independent of its effect on food intake.

15.
Cytokine ; 66(1): 30-9, 2014 Mar.
Article in English | MEDLINE | ID: mdl-24548422

ABSTRACT

TNF-α converting enzyme (TACE) processes the membrane TNF-α to release the bioactive soluble TNF-α. Several evidences suggest the involvement of TNF-α and TACE in inflammatory bowel disease (IBD). Tissue inhibitor of metalloproteinase (TIMP)-3, an endogenous inhibitor of TACE, is positively associated with silent information regulator (SIRT)-1. We aimed to study the expression of TACE, TIMP-3 and SIRT-1 at different stages of colitis and how TACE is regulated in response to SIRT-1 activation. Acute colitis was induced by 3.5% dextran sulfate sodium (DSS) in drinking water for 5days and levels of cytokines and mRNA expression of TACE, TIMP-3 and SIRT-1 were measured in colon at different time intervals. Next, the effect of SIRT-1 activator (resveratrol) or a selective TACE inhibitor (compound 11p) treatment was evaluated. Elevated levels of TNF-α, interleukin (IL)-6, IL-1ß, interferon (IFN)-γ and IL-17 were observed during DSS exposure phase which restored to the normal level after DSS removal. A significant increase in TACE and suppression in TIMP-3 and SIRT-1 mRNA level was observed during DSS exposure phase which reverts back to normal towards the remission phase. Treatment with resveratrol significantly elevated SIRT-1 and TIMP-3 and suppressed TACE mRNA expression and was associated with amelioration of disease. Furthermore, treatment with selective TACE inhibitor significantly suppressed body weight loss, disease activity index, colonic myeloperoxidase activity and the elevated levels of cytokines after DSS challenge. These results strongly emphasize the involvement of TACE in colon inflammation and inhibition of TACE directly or indirectly via SIRT-1 activation ameliorates colitis.


Subject(s)
ADAM Proteins/metabolism , Colon/enzymology , Colon/pathology , Inflammation/enzymology , Sirtuin 1/metabolism , ADAM Proteins/antagonists & inhibitors , ADAM17 Protein , Acute Disease , Animals , Colitis/chemically induced , Colitis/drug therapy , Colitis/pathology , Colon/drug effects , Colon/metabolism , Cytokines/metabolism , Dextran Sulfate , Female , Inflammation/drug therapy , Inflammation/pathology , Kinetics , Mice , Mice, Inbred C57BL , Resveratrol , Stilbenes/pharmacology , Stilbenes/therapeutic use , Time Factors , Tissue Inhibitor of Metalloproteinase-3/metabolism
16.
Can J Physiol Pharmacol ; 92(12): 975-83, 2014 Dec.
Article in English | MEDLINE | ID: mdl-25361428

ABSTRACT

Cannabinoid 1 (CB1) receptor antagonists reduce body weight and improve insulin sensitivity. Preclinical data indicates that an acute dose of CB1 antagonist rimonabant causes an increase in blood glucose. A stable analog of glucagon-like peptide 1 (GLP-1), exendin-4 improves glucose-stimulated insulin secretion in pancreas, and reduces appetite through activation of GLP-1 receptors in the central nervous system and liver. We hypothesized that the insulin secretagogue effect of GLP-1 agonist exendin-4 may synergize with the insulin-sensitizing action of rimonabant. Intraperitoneal as well as intracerebroventricular administration of rimonabant increased serum glucose upon glucose challenge in overnight fasted, diet-induced obese C57 mice, with concomitant rise in serum glucagon levels. Exendin-4 reversed the acute hyperglycemia induced by rimonabant. The combination of exendin-4 and rimonabant showed an additive effect in the food intake, and sustained body weight reduction upon repeated dosing. The acute efficacy of both the compounds was additive for inducing nausea-like symptoms in conditioned aversion test in mice, whereas exendin-4 treatment antagonized the effect of rimonabant on forced swim test upon chronic dosing. Thus, the addition of exendin-4 to rimonabant produces greater reduction in food intake owing to increased aversion, but reduces the other central nervous system side effects of rimonabant. The hyperglucagonemia induced by rimonabant is partially responsible for enhancing the antiobesity effect of exendin-4.


Subject(s)
Anti-Obesity Agents/pharmacology , Glucagon-Like Peptide 1/agonists , Glucagon/metabolism , Obesity/drug therapy , Peptides/pharmacology , Piperidines/pharmacology , Pyrazoles/pharmacology , Receptor, Cannabinoid, CB1/antagonists & inhibitors , Venoms/pharmacology , Animals , Anti-Obesity Agents/therapeutic use , Blood Glucose/metabolism , Body Weight/drug effects , Diet, High-Fat , Drug Synergism , Eating/drug effects , Exenatide , Glucagon-Like Peptide 1/metabolism , Insulin Resistance , Male , Mice, Inbred C57BL , Mice, Obese , Obesity/metabolism , Obesity/physiopathology , Peptides/therapeutic use , Piperidines/therapeutic use , Pyrazoles/therapeutic use , Receptor, Cannabinoid, CB1/metabolism , Rimonabant , Venoms/therapeutic use
17.
Immunopharmacol Immunotoxicol ; 36(4): 282-9, 2014 Aug.
Article in English | MEDLINE | ID: mdl-24946851

ABSTRACT

UNLABELLED: Abstract Context: Tumor necrosis factor (TNF)-α, a potent proinflammatory cytokine, plays a major role in the pathogenesis of cancer. TNF-α converting enzyme (TACE) mediates processing and release of biologically active TNF-α. OBJECTIVE: We aimed to investigate the effect of a novel, selective TACE inhibitor (compound 11p) on skin inflammation and associated tumorigenesis in mice. METHODS: Skin edema was induced in mice by dermal application 12-O-tetradecanoylphorbol-13-acetate (TPA) solution in acetone on to the ear and the effect of post-treatment of compound 11p (topical application) was evaluated. Edema and inflammation was assessed by measuring ear thickness, weight of skin punch and cytokine levels. Skin cancer in mice was initiated by single topical application of 7,12-dimethylbenz[a]anthracene (DMBA) and promoted by repeated TPA application for 20 weeks. The effect of compound 11p on papilloma incidence and multiplicity was evaluated. RESULTS: Treatment with compound 11p strongly suppressed TPA-induced elevation in skin thickness and weight. A dose-dependent suppression in TPA-mediated TNF-α, IL-6, IFN-γ, IL-17 and PGE2 levels which was associated with a decrease in infiltration of inflammatory cells was also observed with the treatment. Moreover, compound 11p treatment delayed the onset, markedly reduced the papilloma incidence and multiplicity persuaded by DMBA and TPA. DISCUSSION AND CONCLUSION: These findings suggest that selective blockade of TACE suppresses TPA-induced epidermal hyperplasia, inflammatory cell infiltration and cytokine level. Inhibition of inflammatory events related to tumor growth might have led to the anti-tumor effect in mouse skin cancer model induced by DMBA and TPA.


Subject(s)
9,10-Dimethyl-1,2-benzanthracene/toxicity , ADAM Proteins/antagonists & inhibitors , Antineoplastic Agents/therapeutic use , Hydroxamic Acids/therapeutic use , Pyrrolidinones/therapeutic use , Skin Neoplasms/prevention & control , Tetradecanoylphorbol Acetate/toxicity , Tumor Necrosis Factor-alpha/antagonists & inhibitors , ADAM17 Protein , Animals , Antineoplastic Agents/administration & dosage , Cocarcinogenesis , Cytokines/immunology , Dose-Response Relationship, Drug , Edema/drug therapy , Edema/immunology , Edema/pathology , Female , Hydroxamic Acids/administration & dosage , Mice, Inbred BALB C , Pyrrolidinones/administration & dosage , Skin/drug effects , Skin/immunology , Skin/pathology , Skin Neoplasms/chemically induced , Skin Neoplasms/immunology , Skin Neoplasms/pathology , Tumor Necrosis Factor-alpha/blood , Tumor Necrosis Factor-alpha/immunology
18.
Drug Res (Stuttg) ; 74(3): 113-122, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38350634

ABSTRACT

Hypoxia-inducible factors (HIFs) are transcription factors that are responsible for adapting to the changes in oxygen levels in the cellular environment. HIF activity determines the expression of cellular proteins that control the development and physiology of the cells and pathophysiology of a disease. Understanding the role of specific HIF (HIF-1-3) in cellular function is essential for development of the HIF-targeted therapies. In this review, we have discussed the use of flow cytometry in analysing HIF function in cells. Proper understanding of HIF-signalling will help to design pharmacological interventions HIF-mediated therapy. We have discussed the role of HIF-signalling in various diseases such as cancer, renal and liver diseases, ulcerative colitis, arthritis, diabetes and diabetic complications, psoriasis, and wound healing. We have also discussed protocols that help to decipher the role of HIFs in these diseases that would eventually help to design promising therapies.


Subject(s)
Arthritis , Signal Transduction , Humans , Flow Cytometry , Kidney , Hypoxia
19.
Pathog Glob Health ; : 1-21, 2024 Mar 20.
Article in English | MEDLINE | ID: mdl-38506667

ABSTRACT

Occupational immunization is an integral part of institutional occupational safety and health (OSH) programs. Laboratory animal workers (LAWs) are personnel working with various small and large vertebrate animals. LAWs are at the risk of contracting a myriad of zoonotic infections as they are occupationally exposed to animals and their biological products. Immunizing employees against such zoonotic pathogens is the best way to prevent disease transmission. This review provides information on various zoonotic diseases, vaccines available to protect against such infections, and vaccination schedules. Certain sections of institutional occupational immunization programs such as risk evaluation, immunizing special categories of personnel and exemption from immunization among others are also described. Additionally, the authors have discussed various probable modes of impact through which occupational immunization of laboratory animal workers fulfills different United Nations Sustainable Development Goals.

20.
Drug Res (Stuttg) ; 2024 Jul 11.
Article in English | MEDLINE | ID: mdl-38991528

ABSTRACT

Complement cascade is a defence mechanism useful for eliminating pathogenic microorganisms and damaged cells. However, activation of alternative complement system can also cause inflammation and promote kidney and retinal disease progression. Inflammation causes tissue hypoxia, which induces hypoxia-inducible factor (HIF) and HIF helps the body to adapt to inflammation. In this study, we investigated the effect of HIF stabilizer desidustat in complement-mediated diseases. Oral administration of desidustat (15 mg/kg) was effective to reduce the kidney injury in mice that was induced by either lipopolysaccharide (LPS), doxorubicin or bovine serum albumin (BSA)-overload. Complement activation-induced membrane attack complex (MAC) formation and factor B activity were also reduced by desidustat treatment. In addition, desidustat was effective against membranous nephropathy caused by cationic BSA and retinal degeneration induced by sodium iodate in mice. C3-deposition, proteinuria, malondialdehyde, and interleukin-1ß were decreased and superoxide dismutase was increased by desidustat treatment in cBSA-induced membranous nephropathy. Desidustat specifically inhibited alternative complement system, without affecting the lectin-, or classical complement pathway. This effect appears to be mediated by inhibition of factor B. These data demonstrate the potential therapeutic value of HIF stabilization by desidustat in treatment of complement-mediated diseases.

SELECTION OF CITATIONS
SEARCH DETAIL