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1.
Eur J Drug Metab Pharmacokinet ; 49(3): 393-403, 2024 May.
Article En | MEDLINE | ID: mdl-38642299

BACKGROUND AND OBJECTIVE: The prediction of pharmacokinetic parameters for drugs metabolised by cytochrome P450 enzymes has been the subject of active research for many years, while the application of in vitro-in vivo extrapolation (IVIVE) techniques for non-cytochrome P450 enzymes has not been thoroughly evaluated. There is still no established quantitative method for predicting hepatic clearance of drugs metabolised by uridine 5'-diphospho-glucuronosyltransferases (UGTs), not to mention those which undergo hepatic uptake. The objective of the study was to predict the human hepatic clearance for telmisartan based on in vitro metabolic stability and hepatic uptake results. METHODS: Telmisartan was examined in liver systems, allowing to estimate intrinsic clearance (CLint, in vitro) based on the substrate disappearance rate with the use of liquid chromatography tandem mass spectrometry (LC-MS/MS) technique. Obtained CLint, in vitro values were corrected for corresponding unbound fractions. Prediction of human hepatic clearance was made from scaled unbound CLint, in vitro data with the use of the well-stirred model, and finally referenced to the literature value of observed clearance in humans, allowing determination of the essential scaling factors. RESULTS: The in vitro scaled CLint, in vitro by UGT1A3 was assessed using three systems, human hepatocytes, liver microsomes, and recombinant enzymes. Obtained values were scaled and hepatic metabolism clearance was predicted, resulting in significant clearance underprediction. Utilization of the extended clearance concept (ECC) and hepatic uptake improved prediction of hepatic metabolism clearance. The scaling factors for hepatocytes, assessing the in vitro-in vivo difference, changed from sixfold difference to only twofold difference with the application of the ECC. CONCLUSIONS: The study showed that taking into consideration hepatic uptake of a drug allows us to obtain satisfactory scaling factors, hence enabling the prediction of in vivo hepatic glucuronidation from in vitro data.


Glucuronides , Glucuronosyltransferase , Microsomes, Liver , Solute Carrier Organic Anion Transporter Family Member 1B3 , Telmisartan , Glucuronosyltransferase/metabolism , Telmisartan/pharmacokinetics , Telmisartan/metabolism , Humans , Microsomes, Liver/metabolism , Glucuronides/metabolism , Solute Carrier Organic Anion Transporter Family Member 1B3/metabolism , Liver/metabolism , Liver/enzymology , Metabolic Clearance Rate , Tandem Mass Spectrometry/methods , Hepatocytes/metabolism , Models, Biological , Chromatography, Liquid/methods , Benzoates/pharmacokinetics , Benzoates/metabolism
2.
Colloids Surf B Biointerfaces ; 236: 113799, 2024 Apr.
Article En | MEDLINE | ID: mdl-38367290

Inflammatory bowel disease (IBD) remains a global health concern with a complex and incompletely understood pathogenesis. In the course of IBD development, damage to intestinal epithelial cells and a reduction in the expression of tight junction (TJ) proteins compromise the integrity of the intestinal barrier, exacerbating inflammation. Notably, the renin-angiotensin system and angiotensin II receptor type 1 (AT1R) play a crucial role in regulating the pathological progression including vascular permeability, and immune microenvironment. Thus, Telmisartan (Tel), an AT1R inhibitor, loading thermosensitive hydrogel was constructed to investigate the potential of alleviating inflammatory bowel disease through rectal administration. The constructed hydrogel exhibits an advantageous property of rapid transformation from a solution to a gel state at 37°C, facilitating prolonged drug retention within the gut while mitigating irritation associated with rectal administration. Results indicate that Tel also exhibits a beneficial effect in ameliorating colon shortening, colon wall thickening, cup cell lacking, crypt disappearance, and inflammatory cell infiltration into the mucosa in colitis mice. Moreover, it significantly upregulates the expression of TJ proteins in colonic tissues thereby repairing the intestinal barrier damage and alleviating the ulcerative colitis (UC) disease process. In conclusion, Tel-loaded hydrogel demonstrates substantial promise as a potential treatment modality for IBD.


Colitis , Inflammatory Bowel Diseases , Mice , Animals , Telmisartan/pharmacology , Telmisartan/metabolism , Hydrogels/pharmacology , Intestinal Mucosa/metabolism , Tight Junctions/metabolism , Tight Junctions/pathology , Inflammatory Bowel Diseases/drug therapy , Inflammatory Bowel Diseases/pathology , Colitis/pathology , Colon/metabolism , Inflammation/metabolism , Dextran Sulfate/metabolism , Disease Models, Animal , Mice, Inbred C57BL
3.
J Transl Med ; 21(1): 511, 2023 07 28.
Article En | MEDLINE | ID: mdl-37507810

BACKGROUND: Preinjury of peripheral nerves triggers dorsal root ganglia (DRG) axon regeneration, a biological change that is more pronounced in young mice than in old mice, but the complex mechanism has not been clearly explained. Here, we aim to gain insight into the mechanisms of axon regeneration after conditioning lesion in different age groups of mice, thereby providing effective therapeutic targets for central nervous system (CNS) injury. METHODS: The microarray GSE58982 and GSE96051 were downloaded and analyzed to identify differentially expressed genes (DEGs). The protein-protein interaction (PPI) network, the miRNA-TF-target gene network, and the drug-hub gene network of conditioning lesion were constructed. The L4 and L5 DRGs, which were previously axotomized by the sciatic nerve conditioning lesions, were harvested for qRT-PCR. Furthermore, histological and behavioral tests were performed to assess the therapeutic effects of the candidate drug telmisartan in spinal cord injury (SCI). RESULTS: A total of 693 and 885 DEGs were screened in the old and young mice, respectively. Functional enrichment indicates that shared DEGs are involved in the inflammatory response, innate immune response, and ion transport. QRT-PCR results showed that in DRGs with preinjury of peripheral nerve, Timp1, P2ry6, Nckap1l, Csf1, Ccl9, Anxa1, and C3 were upregulated, while Agtr1a was downregulated. Based on the bioinformatics analysis of DRG after conditioning lesion, Agtr1a was selected as a potential therapeutic target for the SCI treatment. In vivo experiments showed that telmisartan promoted axonal regeneration after SCI by downregulating AGTR1 expression. CONCLUSION: This study provides a comprehensive map of transcriptional changes that discriminate between young and old DRGs in response to injury. The hub genes and their related drugs that may affect the axonal regeneration program after conditioning lesion were identified. These findings revealed the speculative pathogenic mechanism involved in conditioning-dependent regenerative growth and may have translational significance for the development of CNS injury treatment in the future.


MicroRNAs , Spinal Cord Injuries , Mice , Animals , Axons/metabolism , Axons/pathology , Nerve Regeneration/genetics , Telmisartan/metabolism , Telmisartan/pharmacology , MicroRNAs/genetics , MicroRNAs/metabolism , Spinal Cord
4.
Int Urol Nephrol ; 55(6): 1427-1439, 2023 Jun.
Article En | MEDLINE | ID: mdl-37093439

BACKGROUND: Male infertility is a hot problem worldwide, but there are few treatments, especially male infertility caused by irradiation is difficult to treat. The aim of this study was to investigate and evaluate novel drugs for the treatment of male infertility caused by irradiation. METHODS: we randomly divided 18 male BALB/c mice into 3 groups: control, irradiated, and telmisartan. Both irradiated and telmisartan group completed whole-body 0.5 Gy five times irradiation, and the telmisartan group received intraperitoneal injection of telmisartan (1.2 mg/kg) daily on the next day after irradiation, and all groups were sampled on day 25 after irradiation. RESULTS: Sperm motility results show that total sperm motility of irradiated group was significantly lower compared with control group, and testicular HE results showed that testis in irradiated group were severely damaged. Compared with irradiated group, the total sperm motility, sperm concentration, testicular index, Johnsen score, and the seminiferous tubule layer numbers were higher in telmisartan group (P < 0.05). The immunohistochemical staining showed γ-H2AX expression is higher in telmisartan group compared with irradiated group. And the relative mRNA expression of PLZF, GFRA1, STRA8, DMRT1, SPO11, SYCP2, OVOL2, CCNA1, TJP3, RUNX2, TXNDC2 TNP1, and PRM3 in telmisartan group was all significantly higher than irradiated group (P < 0.05). CONCLUSION: In conclusion, in vivo experiments confirmed that telmisartan ameliorated the spermatogenic disorder in mice caused by fractionated low-dose irradiation via promoting spermatogenesis.


Infertility, Male , Sperm Motility , Male , Mice , Animals , Humans , Telmisartan/metabolism , Telmisartan/pharmacology , Semen , Spermatogenesis , Testis/metabolism , Infertility, Male/drug therapy , Infertility, Male/etiology , Membrane Proteins/metabolism , Thioredoxins/metabolism , Thioredoxins/pharmacology , Transcription Factors/metabolism , Transcription Factors/pharmacology , Zonula Occludens Proteins/metabolism , DNA-Binding Proteins/metabolism , DNA-Binding Proteins/pharmacology
5.
Eur J Pharmacol ; 933: 175254, 2022 Oct 15.
Article En | MEDLINE | ID: mdl-36087696

Puerarin (Pue) has been widely used in the treatment of hypertension and cardiovascular diseases, but the basic mechanism of Pue on myocardial remodeling (MR) of hypertension is not clear. The purpose of this study was to investigate the effect and mechanism of Pue on MR and provide the basis for the clinical application. Thirty male spontaneously hypertensive rats (SHR) and six male Wistar Kyoto rats (WKY) aged 3 months were used in this study, SHR rats were randomly divided into 5 groups, Pue (40 or 80 mg/kg/d, ip) and telmisartan (TELMI) (30 mg/kg/d, ig) were administrated for 12 weeks. We used Echocardiography to detect the cardiac function. Morphology and structure of myocardium were observed. H9C2 cells were subjected to 1 µM Ang Ⅱ in vitro, 100 µM Pue, 0.5 µM Calmodulin-dependent calcineurin (CaN) inhibitor Cyclosporin A (CsA) and 1 µM specific transient receptor potential channel 6 (TRPC6) inhibitor SAR7334 were used in H9C2 cells. Long-term administration of Pue could significantly improve cardiac function, improve morphology and structure of myocardium in vivo. Pue could reduce MR related proteins expression (ACTC1, TGF-ß1, CTGF, ß-MHC and BNP), attenuate ROS, restore MMP and decrease Ca2+-overload in vitro. Further study indicated that Pue could decrease TRPC6 expression and inhibit nuclear factor of activated T cells 3 (NFATc3) nuclear translocation in vitro. These results suggested that puerarin could ameliorate myocardial remodeling through inhibiting TRPC6-CaN-NFATc3 in spontaneously hypertensive rats.


Hypertension , Transient Receptor Potential Channels , Animals , Antihypertensive Agents/therapeutic use , Calcineurin/metabolism , Calmodulin/metabolism , Cyclosporine , Hypertension/drug therapy , Hypertension/metabolism , Isoflavones , Male , Myocardium/metabolism , NFATC Transcription Factors , Rats , Rats, Inbred SHR , Rats, Inbred WKY , Reactive Oxygen Species/metabolism , TRPC Cation Channels , TRPC6 Cation Channel/metabolism , Telmisartan/metabolism , Telmisartan/therapeutic use , Transforming Growth Factor beta1/metabolism , Transient Receptor Potential Channels/metabolism
6.
J Mol Endocrinol ; 69(1): 259-268, 2022 05 10.
Article En | MEDLINE | ID: mdl-35354667

Telmisartan and irbesartan are angiotensin II receptor blockers (ARBs) and reportedly stimulate adiponectin secretion from adipocytes via partial peroxisome proliferator-activated receptor γ (PPARγ) activation. However, quantitative evaluation among different ARBs has not been performed. Adiponectin exerts strong protection against a number of pathological events by suppressing cell death, inhibiting inflammation, and enhancing cell survival, while leptin promotes inflammation, oxidative stress, atherogenesis, and thrombosis. The aim of this study was to identify the most effective ARB enhancing adiponectin secretion without raising leptin secretion from human white adipocytes (HWAs). Among seven ARBs (azilsartan, candesartan, irbesartan, losartan, olmesartan, telmisartan, and valsartan), telmisartan was the most effective ARB for the increase of adiponectin secretion and irbesartan was the second, whereas the other ARBs at 1 µM had no effect on adiponectin secretion. GW9662, a PPARγ antagonist, completely blocked pioglitazone (PPARγ agonist)-induced adiponectin secretion and mRNA expression, whereas it unexpectedly blocked neither telmisartan- nor irbesartan-induced adiponectin secretion and mRNA expression but rather increased them. GW6471, PPARα antagonist, and siRNA for PPARα suppressed telmisartan- and irbesartan-induced adiponectin secretion, suggesting that PPARα is the main target of these ARBs to increase adiponectin secretion in HWAs. Leptin secretion was not affected by any ARBs at 1 µM and GW9662 significantly decreased the basal secretion of leptin, suggesting that basal leptin secretion is regulated in a PPARγ-dependent manner. We conclude that telmisartan is the most effective ARB to increase adiponectin secretion via PPARα without raising leptin secretion from HWAs.


Adiponectin , Angiotensin Receptor Antagonists , Adipocytes/metabolism , Adiponectin/metabolism , Angiotensin II Type 1 Receptor Blockers/metabolism , Angiotensin II Type 1 Receptor Blockers/pharmacology , Angiotensin Receptor Antagonists/metabolism , Angiotensin Receptor Antagonists/pharmacology , Angiotensin-Converting Enzyme Inhibitors/metabolism , Angiotensin-Converting Enzyme Inhibitors/pharmacology , Benzoates/metabolism , Benzoates/pharmacology , Humans , Inflammation/metabolism , Irbesartan/pharmacology , Leptin/metabolism , PPAR alpha/metabolism , PPAR gamma/metabolism , RNA, Messenger/metabolism , Telmisartan/metabolism , Telmisartan/pharmacology
7.
Biotechnol Appl Biochem ; 69(2): 461-468, 2022 Apr.
Article En | MEDLINE | ID: mdl-33578449

Nonalcoholic fatty liver disease (NAFLD) is the most common hepatic disease. It is rapidly emerging as the frequent cause for liver transplantation with the risk of disease recurrence, even after transplantation. Clinical evidence showed an abnormally altered expression of different peroxisome proliferator-activated receptor (PPAR) isotypes (PPAR-α/γ/δ) in NAFLD with an involvement in the induction of insulin resistance, hepatic steatosis, reactive oxygen species (ROS) formation, and hepatic inflammation. Recently, several dual PPAR-γ/α agonists were developed to simultaneously achieve the insulin-sensitizing effect of PPAR-γ as well as lipid catabolizing effect of PPAR-α. PPAR-α activation could counterbalance the steatogenic and adipogenic effects of PPAR-γ. But most of the drugs were ended in the initial level itself due to harmful adverse effects. In the present review, we discuss the possible mechanism of telmisartan, a typical angiotensin receptor blocker with excellent safety and pharmacokinetic profile, as a PPAR-γ/α dual agonist in the treatment of NAFLD.


Non-alcoholic Fatty Liver Disease , Humans , Liver , Non-alcoholic Fatty Liver Disease/drug therapy , Non-alcoholic Fatty Liver Disease/etiology , Non-alcoholic Fatty Liver Disease/metabolism , PPAR alpha/agonists , PPAR alpha/metabolism , PPAR gamma/agonists , PPAR gamma/metabolism , Telmisartan/metabolism , Telmisartan/pharmacology , Telmisartan/therapeutic use
8.
Life Sci ; 291: 120260, 2022 Feb 15.
Article En | MEDLINE | ID: mdl-34968466

Diabetic nephropathy (DN) is a serious complication of diabetes and can lead to renal failure. Telmisartan (TEL) is an approved angiotensin II type 1 receptor blocker for the treatment of hypertension and possesses nephroprotective efficacy. The study investigated the beneficial effect of TEL on renal oxidative stress, inflammatory response, and apoptosis in type 1 diabetic rats, pointing to the possible role of Nrf2/HO-1 signaling. Diabetes was induced by streptozotocin (STZ), and TEL (5 and 10 mg/kg) was supplement for 8 weeks. TEL ameliorated hyperglycemia, prevented body weight loss and kidney hypertrophy, decreased serum creatinine and urea, and prevented histopathological alterations in diabetic rats. Malondialdehyde (MDA), nitric oxide (NO), NF-κB p65 and TNF-α were increased, whereas GSH, SOD and Bcl-2 were decreased in the kidney of diabetic rats. Treatment with TEL ameliorated oxidative stress, suppressed NF-κB p65 and TNF-α, and boosted cellular antioxidant defenses and Bcl-2. TEL upregulated Nrf2 and HO-1 in the kidney of both normal and diabetic rats. In addition, TEL downregulated VEGF and MMP-9 in the kidney of diabetic rats. In silico molecular docking simulations revealed the potent binding affinity of TEL to NF-κB, MMP-9, Keap1 and HO-1. In conclusion, TEL attenuates DN by ameliorating hyperglycemia, oxidative stress, inflammation, apoptosis and angiogenesis and upregulation of Nrf2/HO-1 signaling.


Diabetic Nephropathies/drug therapy , Telmisartan/pharmacology , Animals , Diabetes Mellitus, Experimental/drug therapy , Diabetes Mellitus, Experimental/metabolism , Heme Oxygenase (Decyclizing)/metabolism , Inflammation , Kidney/metabolism , Kidney/pathology , Male , Molecular Docking Simulation , NF-E2-Related Factor 2/metabolism , Oxidative Stress , Rats , Rats, Sprague-Dawley , Signal Transduction/drug effects , Streptozocin/pharmacology , Telmisartan/metabolism
9.
Pharm Nanotechnol ; 8(4): 313-322, 2020.
Article En | MEDLINE | ID: mdl-32515316

BACKGROUND: Hypertension and hypercholesterolemia are two main physiological risk factors of cardiovascular disease, and commonly occur in combination. Multicompound combination therapy is rational for the treatment of concurrent hypertension and hypercholesterolemia, while telmisartan and pitavastatin calcium can be used as a potential drug combination. OBJECTIVE: The aim of this paper is to study the intestinal absorption and absorption interaction of telmisartan and pitavastatin calcium. METHODS: An HPLC method was developed and validated to determine telmisartan and pitavastatin calcium in intestinal perfusate simultaneously. The in situ single-pass perfusion in rats was utilized to investigate the effects of concentrations, intestinal segment (duodenum, jejunum, ileum and colon) and co-administrated drugs on absorption. RESULTS: The effective permeability coefficient and the absorption rate constant of telmisartan were higher in the duodenum as compared to other intestinal segments. However, the intestinal absorption of pitavastatin calcium was not segmental dependent. The effective permeability coefficient and absorption rate constant have no significant difference among three concentrations of telmisartan, pitavastatin calcium individually and their combination. CONCLUSION: The results showed that telmisartan and pitavastatin calcium were transported passively, and telmisartan and pitavastatin calcium could be absorbed well in all intestinal segments. The intestinal absorption parameters revealed the absence of any intestinal absorption interaction when co-administered. Lay Summary: Co-administration of telmisartan and pitavastatin calcium can provide a potential therapeutic strategy for the treatment of concurrent hypertension and hypercholesterolemia. We are investigating the intestinal interaction of these two drugs in rats using the developed HPLC method and in situ single-pass perfusion technology. We will calculate some parameters after administrating two types of drugs either separately or together, which help reflect changes regarding intestinal absorption and penetration. Compared with telmisartan and pitavastatin calcium administrated separately, if parameters significantly change after co-administration, it proves the existence of the intestinal interactions. Moreover, the results might contribute to clinic drug monitoring.


Angiotensin II Type 1 Receptor Blockers/metabolism , Chromatography, High Pressure Liquid , Colon/metabolism , Hydroxymethylglutaryl-CoA Reductase Inhibitors/metabolism , Intestinal Absorption , Intestine, Small/metabolism , Quinolines/metabolism , Telmisartan/metabolism , Animals , Perfusion , Permeability , Rats, Sprague-Dawley
10.
Drug Metab Pharmacokinet ; 34(5): 293-299, 2019 Oct.
Article En | MEDLINE | ID: mdl-31564410

The pharmacokinetics of telmisartan are nonlinear within the clinical dose range. To identify the underlying mechanism of this nonlinearity, we conducted a PET study in healthy subjects using [11C]telmisartan. Eight healthy male subjects were enrolled in a 2-way crossover study. PET imaging was performed after intravenous administration of [11C]telmisartan with or without a 1-h oral predose of two 40 mg Micardis® tablets. About 60% of the injected [11C]telmisartan accumulated in the liver within 10 min after injection. With predosing of 80 mg telmisartan, the systemic elimination of [11C]telmisartan was slightly delayed, but the liver exposure started to decrease earlier and biliary excretion was greatly enhanced. Hepatic uptake clearance of the radioactivity was not changed by telmisartan predosing, whereas the biliary clearance of radioactivity from the liver was significantly increased. Thus, the alteration in the pharmacokinetics of the radioactivity could not be explained simply by the saturation of hepatic uptake. Therefore, other mechanisms, such as the saturation of intracellular binding of telmisartan and/or its glucuronide, and the glucuronidation of telmisartan by uridine 5'-diphospho-glucuronosyltransferases, should be considered. This is the first reported human PET study using [11C]telmisartan, the results of which can assist understanding of the hepatobiliary transport of telmisartan in humans.


Bile/metabolism , Liver/metabolism , Positron-Emission Tomography , Telmisartan/analysis , Adult , Biological Transport , Carbon Radioisotopes , Cross-Over Studies , Healthy Volunteers , Humans , Injections, Intravenous , Liver/chemistry , Male , Molecular Structure , Telmisartan/administration & dosage , Telmisartan/metabolism , Young Adult
11.
Life Sci ; 221: 159-167, 2019 Mar 15.
Article En | MEDLINE | ID: mdl-30769114

AIMS: Renin-angiotensin system (RAS) and natriuretic peptides system (NPS) perturbations govern the development of diabetic nephropathy (DN). Hence, in search of a novel therapy against DN, present study targeted both, NPS and RAS simultaneously using a neprilysin inhibitor (NEPi) in combination with either angiotensin receptor blocker (ARB) or angiotensin-converting enzyme 2 (ACE2) activator. METHODS: We induced diabetes in male Wistar rats by a single dose of streptozotocin (55 mg/kg, i.p.). After four weeks, we treated diabetic rats with thiorphan, telmisartan or diminazene aceturate (Dize) 0.1, 10, 5 mg/kg/day, p.o. alone as monotherapy, or both thiorphan/telmisartan or thiorphan/Dize as combination therapy, for four weeks. Then, plasma and urine biochemistry were performed, and kidneys from all the groups were collected and processed separately for histopathology, ELISA and Western blotting. KEY FINDINGS: Proposed combination therapies attenuated metabolic perturbations, prevented renal functional decline, and normalised adverse alterations in renal ACE, ACE2, Ang-II, Ang-(1-7), neprilysin and cGMP levels in diabetic rats. Histopathological evaluation revealed a significant reduction in glomerular and tubulointerstitial fibrosis by combination therapies. Importantly, combination therapies inhibited inflammatory, profibrotic and apoptotic signalling, way better than respective monotherapies, in preventing DN. CONCLUSION: Renoprotective potential of thiorphan (NEPi)/telmisartan (ARB) and thiorphan/Dize (ACE2 activator) combination therapies against the development of DN is primarily attributed to normalisation of RAS and NPS components and inhibition of pathological signalling related to inflammation, fibrosis, and apoptosis. Hence, we can conclude that NEPi/ARB and NEPi/ACE2 activator combination therapies might be new therapeutic strategies in preventing DN.


Diabetic Nephropathies/metabolism , Neprilysin/metabolism , Renin-Angiotensin System/physiology , Angiotensin-Converting Enzyme 2 , Animals , Apoptosis , Diabetes Mellitus, Experimental/metabolism , Diabetic Nephropathies/prevention & control , Diminazene/analogs & derivatives , Diminazene/metabolism , Diminazene/pharmacology , Fibrosis , Inflammation , Kidney/pathology , Male , Neprilysin/antagonists & inhibitors , Peptidyl-Dipeptidase A , Rats , Rats, Wistar , Renin-Angiotensin System/drug effects , Streptozocin , Telmisartan/metabolism , Telmisartan/pharmacology , Thiorphan/metabolism , Thiorphan/pharmacology
12.
Life Sci ; 221: 109-120, 2019 Mar 15.
Article En | MEDLINE | ID: mdl-30699330

AIMS: The heterodimerization of angiotensin II receptors (AT1R and AT2R) with adiponectin receptor AdipoR1 and AdipoR2 may instigate high glucose (HG)-induced renal tubulointerstitial injury. This study examined the effect of telmisartan on diabetic nephropathy (DN) and its underlying mechanism. MAIN METHODS: Diabetes was induced in rats through a single intraperitoneal injection of streptozotocin. Diabetic rats treated with or without the intravenous injection of AdipoR1 siRNA were intragastrically administered with 5 mg/kg/d telmisartan or a vehicle for 12 weeks. The rat proximal tubular epithelial cell line NRK-52E was treated with HG (30 mmol/L) with or without telmisartan (10 µM) for 48 h. KEY FINDINGS: In streptozotocin-induced diabetic rats, telmisartan treatment could decrease the inulin clearance rate, restore the glomerular surface area and mesangial area, alleviate renal fibrosis, and decrease urinary albumin excretion. Furthermore, diabetic rats exhibited increased AT1R-AdipoR1 heterodimers in the renal tubular compartment, which could be attenuated by telmisartan treatment, accompanied by a decrease in the expression level of cytokines MIP-1α, ICAM-1 and MCP-1. In vitro, HG promoted the dimerization formation of AT1R-AdipoR1 in cultured NRK-52E cells, but this effect was not found in NRK-52E cells transfected with the AdipoR1-G269E,G273E mutant. Telmisartan could inhibit HG-induced AT1R-AdipoR1 dimerization, downregulate the expression levels of inflammatory cytokines, and alleviate cell apoptosis in NRK-52E cells. Furthermore, AdipoR1 knockdown could abate the renoprotective benefits of telmisartan. SIGNIFICANCE: The heterodimerization of AT1R-AdipoR1 probably contributes to the renal injury of DN, and provides an additional mechanistic insight into how telmisartan prevents the development and progression of DN.


Diabetic Nephropathies/drug therapy , Diabetic Nephropathies/metabolism , Telmisartan/metabolism , Animals , Cell Line , Diabetes Mellitus, Experimental , Dimerization , Disease Models, Animal , Fibrosis , Kidney/physiopathology , Male , RNA, Small Interfering , Rats , Rats, Wistar , Receptor, Angiotensin, Type 1/drug effects , Receptors, Adiponectin/drug effects , Streptozocin/pharmacology , Telmisartan/pharmacology
13.
Biopharm Drug Dispos ; 40(2): 62-69, 2019 Feb.
Article En | MEDLINE | ID: mdl-30652318

The hepatic uptake of clinical drugs mediated by human hepatic organic anion transporting polypeptides (OATP/SLCO) has been reported extensively. In this study, hepatic uptake by recombinantly expressed monkey OATP1B1, OATP1B3 and OATP2B1 was investigated using three human OATP1B1 and OATP1B3 substrates (pitavastatin, pravastatin and rosuvastatin) and one OATP1B3 substrate (telmisartan), as the governmental drug interaction guidelines recommend, and seven reported clinical drugs. The uptake of known human probes into recombinant OATP-expressing cells was significantly greater than that of mock cells. Consequently, pitavastatin, pravastatin and rosuvastatin were suggested to be substrates of recombinant monkey OATP1B1 and OATP1B3, and telmisartan was suggested to be a substrate of recombinant monkey OATP1B3, in a manner similar to human OATPs. In contrast, atorvastatin, bosentan, etoposide, fexofenadine, fluvastatin, glibenclamide and simeprevir were broadly transported by recombinant monkey OATP1B1, OATP1B3 and OATP2B1. Furthermore, some of the 16 non-synonymous monkey OATP1B1 variants found in 64 cynomolgus and 32 rhesus monkeys mediated up to a 1.6-fold [3 H]pitavastatin uptake (with low Michaelis constant values) in comparison with the wild type under the present conditions. Despite sequences of monkey recombinant OATPs not being totally reflective of those of human OATPs, our results collectively suggested that OATP1B1, OATP1B3 or OATP2B1 in monkeys could mediate roughly a similar hepatic uptake of various OATP probes. Recombinant monkey OATPs would be good experimental tools for in vitro hepatic uptake in cell systems.


Organic Anion Transporters/metabolism , Quinolines/metabolism , Recombinant Proteins/metabolism , Telmisartan/metabolism , Animals , Drug Interactions , HEK293 Cells , Humans , Liver-Specific Organic Anion Transporter 1/genetics , Liver-Specific Organic Anion Transporter 1/metabolism , Macaca fascicularis , Macaca mulatta , Organic Anion Transporters/genetics , Plasmids , Pravastatin/metabolism , Recombinant Proteins/genetics , Rosuvastatin Calcium/metabolism , Solute Carrier Organic Anion Transporter Family Member 1B3/genetics , Solute Carrier Organic Anion Transporter Family Member 1B3/metabolism , Substrate Specificity
14.
AAPS PharmSciTech ; 19(7): 2990-2999, 2018 Oct.
Article En | MEDLINE | ID: mdl-30043191

To overcome the poor dissolution of telmisartan (TMS) at weak acidic pH, amorphous alkalinized TMS (AAT) was prepared by introducing sodium hydroxide as a selective alkalizer. AAT-containing polymeric solid dispersions were prepared by a solvent evaporation method; these solid dispersions were AAT-PEG, AAT-PVP, AAT-POL, and AAT-SOL for the polymers of PEG 6000, PVP K30, Poloxamer 407, and Soluplus, respectively. The characteristics of the different formulations were observed by differential scanning calorimetry, powder X-ray diffraction, Fourier transform infrared spectroscopy, and scanning electron microscopy. To compare the supersaturation behavior, a dissolution test was performed at 37 ± 0.5 °C either in 900 ml (plain condition) or 500 ml (limited condition) of pH 6.8-simulated intestinal fluid used as a medium. AAT-SOL exhibited enhanced dissolution, indicating the probability of extended supersaturation in the limited condition. AAT-SOL was further formulated into a tablet by introducing other excipients, Vivapur 105 and Croscarmellose, as a binder and superdisintegrant, respectively, using a direct compression method. The selected AAT-SOL tablet was superior to Micardis (the reference product) in the aspect of supersaturation maintenance during dissolution in the limited condition, suggesting that it is a promising candidate for practical development that can replace the commercial product in the future.


Antacids/chemistry , Drug Compounding/methods , Telmisartan/chemistry , Antacids/metabolism , Antihypertensive Agents/chemistry , Antihypertensive Agents/metabolism , Calorimetry, Differential Scanning/methods , Excipients/chemistry , Excipients/metabolism , Microscopy, Electron, Scanning/methods , Polymers/chemistry , Polymers/metabolism , Solvents/chemistry , Solvents/metabolism , Spectroscopy, Fourier Transform Infrared/methods , Tablets , Telmisartan/metabolism , X-Ray Diffraction/methods
15.
AAPS J ; 20(2): 33, 2018 02 21.
Article En | MEDLINE | ID: mdl-29468289

Freshly-isolated rat hepatocytes are commonly used as tools for hepatic drug disposition. From an ethical point of view, it is important to maximize the use of isolated hepatocytes by cryopreservation. The present study compared overall hepatocyte functionality as well as activity of the organic anion transporting polypeptide (Oatp), multidrug resistance-associated protein 2 (Mrp2), and UDP-glucuronosyltransferase 1 (Ugt1), in in vitro models established with cryopreserved and freshly-isolated hepatocytes. A similar culture time-dependent decline in cellular functionality, as assessed by urea production, was observed in sandwich-cultured hepatocytes (SCH) obtained from freshly-isolated and cryopreserved cells. Concentration-dependent uptake kinetics of the Oatp substrate sodium fluorescein in suspended hepatocytes (SH) or SCH were not significantly affected by cryopreservation. Mrp2-mediated biliary excretion of 5 (and 6)-carboxy-2',7'-dichlorofluorescein by SCH was assessed with semi-quantitative fluorescence imaging: biliary excretion index values increased between day 3 and day 4, but did not differ significantly between cryopreserved and freshly-isolated hepatocytes. Finally, telmisartan disposition was evaluated in SCH to simultaneously explore Oatp, Ugt1, and Mrp2 activity. In order to distinguish between the susceptibilities of the individual disposition pathways to cryopreservation, a mechanistic cellular disposition model was developed. Basolateral and canalicular efflux as well as glucuronidation of telmisartan were affected by cryopreservation. In contrast, the disposition parameters of telmisartan-glucuronide were not impacted by cryopreservation. Overall, the relative contribution of the rate-determining processes (uptake, metabolism, efflux) remained unaltered between cryopreserved and freshly-isolated hepatocytes, indicating that cryopreserved hepatocytes are a suitable alternative for freshly-isolated hepatocytes when studying these cellular disposition pathways.


Cell Culture Techniques/methods , Cryopreservation , Hepatocytes/metabolism , ATP-Binding Cassette Transporters/metabolism , Animals , Cells, Cultured , Glucuronides/chemistry , Glucuronosyltransferase/metabolism , Liver/cytology , Male , Organic Anion Transporters/metabolism , Rats , Rats, Wistar , Telmisartan/chemistry , Telmisartan/metabolism
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