1
|
Enache AE, Dietrich UM, Drury O, Trucco E, MacGillivray T, Syme H, Elliott J, Chang YM. Changes in retinal vascular diameters in senior and geriatric cats in association with variation in systemic blood pressure. J Feline Med Surg 2021; 23:1129-1139. [PMID: 33739170 PMCID: PMC10812161 DOI: 10.1177/1098612x21997629] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
OBJECTIVES Early diagnosis of arterial hypertension is essential to prevent target organ damage. In humans, retinal arteriolar narrowing predicts hypertension. This blinded prospective observational study investigated the retinal vessel diameters in senior and geriatric cats of varying systolic blood pressure (SBP) status and evaluated retinal vascular changes in hypertensive cats after treatment. METHODS Cats with a median age of 14 years (range 9.1-22 years) were categorised into five groups: group 1, healthy normotensive (SBP <140 mmHg; n = 40) cats; group 2, pre-hypertensive (SBP 140-160 mmHg; n = 14) cats; group 3, cats with chronic kidney disease (CKD) and normotensive (n = 26); group 4, cats with CKD and pre-hypertensive (n = 13); and group 5, hypertensive cats (SBP >160 mmHg, n = 15). Colour fundus images (Optibrand ClearView) were assessed for hypertensive lesions. Retinal vascular diameters and bifurcation angles were annotated and calculated using the Vascular Assessment and Measurement Platform for Images of the Retina annotation tool (VAMPIRE-AT). When available, measurements were obtained at 3 and 6 months after amlodipine besylate treatment. RESULTS Ten hypertensive cats had retinal lesions, most commonly intraretinal haemorrhages and retinal exudates. Arteriole and venule diameters decreased significantly with increasing age (-0.17 ± 0.05 pixels/year [P = 0.0004]; -0.19 ± 0.05 pixels/year). Adjusted means ± SEM for arteriole and venule diameter (pixels) were 6.3 ± 0.2 and 8.9 ± 0.2 (group 1); 7.6 ± 0.3 and 10.1 ± 0.4 (group 2); 6.9 ± 0.2 and 9.5 ± 0.3 (group 3); 7.4 ± 0.3 and 10.0 ± 0.4 (group 4); and 7.0 ± 0.3 and 9.8 ± 0.4 (group 5). Group 1 arteriole and venule diameters were significantly lower than those of groups 2 and 4. Group 2 arteriole bifurcation angle was significantly narrower than those of groups 1 and 3. Post-treatment, vessel diameters decreased significantly at 3 and 6 months in seven hypertensive cats. CONCLUSIONS AND RELEVANCE Increased age was associated with reduced vascular diameters. Longitudinal studies are required to assess if vessel diameters are a risk indicator for hypertension in cats.
Collapse
Affiliation(s)
- Andra-Elena Enache
- North Downs, Specialist Referrals, 3 & 4 The Brewerstreet Dairy Business Park, Brewer Street, Bletchingley, UK
| | | | - Oscar Drury
- Department of Comparative Biomedical Sciences, Royal Veterinary College, London, UK
| | - Emanuele Trucco
- VAMPIRE Project, Computing, School of Science and Engineering, University of Dundee, Dundee, UK
| | - Tom MacGillivray
- VAMPIRE Project, Centre for Clinical Brain Sciences, University of Edinburgh, UK
| | - Harriet Syme
- Department of Clinical Sciences and Services, Queen Mother Hospital for Animals, Royal Veterinary College, London, UK
| | - Jonathan Elliott
- Department of Comparative Biomedical Sciences, Royal Veterinary College, London, UK
| | - Yu-Mei Chang
- Department of Comparative Biomedical Sciences, Royal Veterinary College, London, UK
| |
Collapse
|
2
|
Wu L, Qin L, Nie Y, Xu Y, Zhao YL. Computer-aided understanding and engineering of enzymatic selectivity. Biotechnol Adv 2021; 54:107793. [PMID: 34217814 DOI: 10.1016/j.biotechadv.2021.107793] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Revised: 04/26/2021] [Accepted: 06/28/2021] [Indexed: 12/26/2022]
Abstract
Enzymes offering chemo-, regio-, and stereoselectivity enable the asymmetric synthesis of high-value chiral molecules. Unfortunately, the drawback that naturally occurring enzymes are often inefficient or have undesired selectivity toward non-native substrates hinders the broadening of biocatalytic applications. To match the demands of specific selectivity in asymmetric synthesis, biochemists have implemented various computer-aided strategies in understanding and engineering enzymatic selectivity, diversifying the available repository of artificial enzymes. Here, given that the entire asymmetric catalytic cycle, involving precise interactions within the active pocket and substrate transport in the enzyme channel, could affect the enzymatic efficiency and selectivity, we presented a comprehensive overview of the computer-aided workflow for enzymatic selectivity. This review includes a mechanistic understanding of enzymatic selectivity based on quantum mechanical calculations, rational design of enzymatic selectivity guided by enzyme-substrate interactions, and enzymatic selectivity regulation via enzyme channel engineering. Finally, we discussed the computational paradigm for designing enzyme selectivity in silico to facilitate the advancement of asymmetric biosynthesis.
Collapse
Affiliation(s)
- Lunjie Wu
- School of Biotechnology and Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China
| | - Lei Qin
- School of Biotechnology and Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China
| | - Yao Nie
- School of Biotechnology and Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China; Suqian Industrial Technology Research Institute of Jiangnan University, Suqian 223814, China.
| | - Yan Xu
- School of Biotechnology and Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China; State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, China.
| | - Yi-Lei Zhao
- State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic and Developmental Sciences, MOE-LSB & MOE-LSC, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China
| |
Collapse
|
3
|
Protective effect of quercetin against myocardial ischemia as a Ca 2+ channel inhibitor: involvement of inhibiting contractility and Ca 2+ influx via L-type Ca 2+ channels. Arch Pharm Res 2020; 43:808-820. [PMID: 32761308 DOI: 10.1007/s12272-020-01261-y] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2020] [Accepted: 08/01/2020] [Indexed: 02/07/2023]
Abstract
Many studies describe the stimulating effect of quercetin on Ca2+ channels and the treatment of cardiovascular diseases such as myocardial ischemia and hypertension. However, these studies are scattered and contradictory. The aim of this study is to elucidate the protective effects of quercetin against isoproterenol (ISO)-induced myocardial ischemia and verify the cellular mechanisms based on the L-type Ca2+ channel (LTCC), Ca2+ transients, and myocardial contractility. An animal model of myocardial ischemia was established by subcutaneous injection of ISO for 2 days. Quercetin significantly reduced J-point elevation, heart rate, reactive oxygen species, serum levels of myocardial enzymes, superoxide dismutase, catalase, glutathione, glutathione peroxidase, glutathione S-transferase and improved heart pathologic morphology. L-type Ca2+ current (ICa-L) was tested in an experiment with isolated rat myocardial cells by using the whole-cell patch-clamp recording technique and IonOptix Myocam detection system. Quercetin reduced ICa-L in a concentration-dependent fashion with a half-maximal inhibitory concentration of 4.67 × 10-4 M. Quercetin also shifted the current-voltage curve upwards, moved the activation and inactivation curves to the left and inhibited the amplitude of the cell shortening and Ca2+ transients. The results showed that quercetin acts as a LTCC inhibitor and exerts a cardioprotective effect by inhibiting Ca2+ influx and contractility in rats.
Collapse
|
4
|
Wang L, Liu W, Zhang Z, Tian Y. Validated LC-MS/MS method for the determination of amlodipine enantiomers in rat plasma and its application to a stereoselective pharmacokinetic study. J Pharm Biomed Anal 2018; 158:74-81. [PMID: 29860181 DOI: 10.1016/j.jpba.2018.05.037] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2018] [Revised: 05/16/2018] [Accepted: 05/21/2018] [Indexed: 02/05/2023]
Abstract
A rapid and sensitive method was established to determine amlodipine enantiomers using liquid chromatography-tandem mass spectrometry (LC-MS/MS). Stereoselective separation was performed on CHIRALCEL OZ-RH column (150 mm × 4.6 mm i.d., 5 μm) with acetonitrile-water (10 mM ammonium acetate, 0.5% ammonia solution) (95:5, v/v) at a flow rate of 0.5 mL/min. The substances were detected by mass spectrometer equipped with an electrospray ionization source interface in positive ion mode. Multiple reaction monitoring was selected with the transition of the m/z 409.1 → 238.0 for amlodipine enantiomers and m/z 237.0 → 194.1 for carbamazepine (IS) respectively. Calibration curves were linear at the range of 0.9375-120 ng/mL for both isomers with r > 0.99, while using a lower sample volume (50 μL) compared with previously reported enantiospecific methods The accuracy was at the range of 84.1-119.0% for R-amlodipine, and 87.4-118.2% for S-amlodipine, respectively. The within- and between-run precision (CV%) was within 10% in all cases for both enantiomers. Enantiomers were stable under different conditions, e.g. processed sample, short-term, residue, long-term and freeze/thaw. The LC-MS/MS method was successfully applied in pharmacokinetic study of amlodipine enantiomers in rats. It was observed the concentration of the S- amlodipine was significantly higher than that of the R-amlodipine in racemate-treated group. And there was no significant difference in the pharmacokinetic profiles of the S-amlodipine between the 10 mg/kg racemate- and 5 mg/kg S-amlodipine-treated groups. In addition, it was the first time to find that the main pharmacokinetic parameters (AUC(0-t), AUC(0-∞) and Cmax) of R-amlodipine were significantly lower in the 5 mg/kg R-amlodipine-treated group compared with the racemate-treated group.
Collapse
Affiliation(s)
- Lijuan Wang
- Key Laboratory of Drug Quality Control and Pharmacovigilance, China Pharmaceutical University, 24 Tongjia lane, Nanjing 210009, China; Key Laboratory of Drug Consistency Evaluation, China Pharmaceutical University, Nanjing 210009, China
| | - Wenxia Liu
- Key Laboratory of Drug Quality Control and Pharmacovigilance, China Pharmaceutical University, 24 Tongjia lane, Nanjing 210009, China; Key Laboratory of Drug Consistency Evaluation, China Pharmaceutical University, Nanjing 210009, China
| | - Zunjian Zhang
- Key Laboratory of Drug Quality Control and Pharmacovigilance, China Pharmaceutical University, 24 Tongjia lane, Nanjing 210009, China; Key Laboratory of Drug Consistency Evaluation, China Pharmaceutical University, Nanjing 210009, China; State Key Laboratory of Natural Medicine, China Pharmaceutical University, Nanjing 210009, China.
| | - Yuan Tian
- Key Laboratory of Drug Quality Control and Pharmacovigilance, China Pharmaceutical University, 24 Tongjia lane, Nanjing 210009, China; Key Laboratory of Drug Consistency Evaluation, China Pharmaceutical University, Nanjing 210009, China.
| |
Collapse
|
5
|
Li RWS, Yang C, Shan L, Zhang Z, Wang Y, Kwan Y, Lee SM, Hoi MP, Chan S, Cheung AC, Cheung K, Leung GP. Relaxation effect of a novel Danshensu/tetramethylpyrazine derivative on rat mesenteric arteries. Eur J Pharmacol 2015; 761:153-60. [DOI: 10.1016/j.ejphar.2015.04.041] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2014] [Revised: 04/21/2015] [Accepted: 04/22/2015] [Indexed: 12/13/2022]
|
6
|
Christophersen P, Wulff H. Pharmacological gating modulation of small- and intermediate-conductance Ca(2+)-activated K(+) channels (KCa2.x and KCa3.1). Channels (Austin) 2015. [PMID: 26217968 DOI: 10.1080/19336950.2015.1071748] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
This short review discusses pharmacological modulation of the opening/closing properties (gating) of small- and intermediate-conductance Ca(2+)-activated K(+) channels (KCa2 and KCa3.1) with special focus on mechanisms-of-action, selectivity, binding sites, and therapeutic potentials. Despite KCa channel gating-modulation being a relatively novel field in drug discovery, efforts in this area have already revealed a surprising plethora of pharmacological sites-of-actions and channel subtype selectivity exerted by different chemical classes. The currently published positive modulators show that such molecules are potentially useful for the treatment of various neurodegenerative disorders such as ataxia, alcohol dependence, and epilepsy as well as hypertension. The negative KCa2 modulators are very effective agents for atrial fibrillation. The prediction is that further unraveling of the molecular details of gating pharmacology will allow for the design of even more potent and subtype selective KCa modulators entering into drug development for these indications.
Collapse
Affiliation(s)
| | - Heike Wulff
- b Department of Pharmacology ; University of California, Davis ; Davis , CA USA
| |
Collapse
|
7
|
Inhibitory effect of cinobufagin on L-type Ca2+ currents, contractility, and Ca2+ homeostasis of isolated adult rat ventricular myocytes. ScientificWorldJournal 2014; 2014:496705. [PMID: 24977199 PMCID: PMC4058228 DOI: 10.1155/2014/496705] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2014] [Revised: 04/15/2014] [Accepted: 04/23/2014] [Indexed: 11/17/2022] Open
Abstract
Cinobufagin (CBG), a major bioactive ingredient of the bufanolide steroid compounds of Chan Su, has been widely used to treat coronary heart disease. At present, the effect of CBG on the L-type Ca(2+) current (I Ca-L) of ventricular myocytes remains undefined. The aim of the present study was to characterize the effect of CBG on intracellular Ca(2+) ([Ca(2+)]i) handling and cell contractility in rat ventricular myocytes. CBG was investigated by determining its influence on I Ca-L, Ca(2+) transient, and contractility in rat ventricular myocytes using the whole-cell patch-clamp technique and video-based edge-detection and dual-excitation fluorescence photomultiplier systems. The dose of CBG (10(-8) M) decreased the maximal inhibition of CBG by 47.93%. CBG reduced I Ca-L in a concentration-dependent manner with an IC50 of 4 × 10(-10) M, upshifted the current-voltage curve of I Ca-L, and shifted the activation and inactivation curves of I Ca-L leftward. Moreover, CBG diminished the amplitude of the cell shortening and Ca(2+) transients with a decrease in the time to peak (Tp) and the time to 50% of the baseline (Tr). CBG inhibited L-type Ca(2+) channels, and reduced [Ca(2+)]i and contractility in adult rat ventricular myocytes. These findings contribute to the understanding of the cardioprotective efficacy of CBG.
Collapse
|
8
|
Carrillo ED, Escobar Y, González G, Hernández A, Galindo JM, García MC, Sánchez JA. Posttranscriptional regulation of the β2-subunit of cardiac L-type Ca2+ channels by MicroRNAs during long-term exposure to isoproterenol in rats. J Cardiovasc Pharmacol 2011; 58:470-8. [PMID: 21753737 DOI: 10.1097/fjc.0b013e31822a789b] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
INTRODUCTION AND METHODS The effects of long-term β-adrenergic administration on the expression levels of the cardiac L-type Ca channel β2 subunit, which regulates channel trafficking and function, were characterized in adult rats. RESULTS Systemic administration of isoproterenol (150 mg·kg·h) for 2 d led to a 50% increase in the ventricular wet weight-to-body weight ratio (mg/g) and of more than two-fold in the expression of actin protein. In contrast, β2 subunit protein levels decreased (down to 49%), while mRNA levels remained unchanged. Furthermore, levels of microRNAs (miRs), including miR-21 and miR-132, were upregulated (7.2 and 7.9 fold, respectively). Transfection of these miRs into HEK293 cells attenuated expression of a luciferase reporter gene controlled by a conserved 3'-untranslated region (UTR) of the β2 subunit (down to 67% and 56%, respectively). Systemic administration of isoproterenol also led to briefer intracellular Ca transients during action potentials measured in isolated cardiomyocytes (down to 65%). CONCLUSION These results suggest that cardiac L-type Ca channel β2 subunit protein expression may be downregulated by miRs in response to long-term activation of β-adrenergic signaling, possibly as an adaptive response in cardiac hypertrophy and sustained β-adrenergic states.
Collapse
Affiliation(s)
- Elba D Carrillo
- Departamento de Farmacología, Centro de Investigación y de Estudios Avanzados, del Instituto Politécnico Nacional, México, DF, México
| | | | | | | | | | | | | |
Collapse
|
9
|
Cao X, Lee YT, Holmqvist M, Lin Y, Ni Y, Mikhailov D, Zhang H, Hogan C, Zhou L, Lu Q, Digan ME, Urban L, Erdemli G. Cardiac ion channel safety profiling on the IonWorks Quattro automated patch clamp system. Assay Drug Dev Technol 2010; 8:766-80. [PMID: 21133679 DOI: 10.1089/adt.2010.0333] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
The normal electrophysiologic behavior of the heart is determined by the integrated activity of specific cardiac ionic currents. Mutations in genes encoding the molecular components of individual cardiac ion currents have been shown to result in multiple cardiac arrhythmia syndromes. Presently, 12 genes associated with inherited long QT syndrome (LQTS) have been identified, and the most common mutations are in the hKCNQ1 (LQT1, Jervell and Lange-Nielson syndrome), hKCNH2 (LQT2), and hSCN5A (LQT3, Brugada syndrome) genes. Several drugs have been withdrawn from the market or received black box labeling due to clinical cases of QT interval prolongation, ventricular arrhythmias, and sudden death. Other drugs have been denied regulatory approval owing to their potential for QT interval prolongation. Further, off-target activity of drugs on cardiac ion channels has been shown to be associated with increased mortality in patients with underlying cardiovascular diseases. Since clinical arrhythmia risk is a major cause for compound termination, preclinical profiling for off-target cardiac ion channel interactions early in the drug discovery process has become common practice in the pharmaceutical industry. In the present study, we report assay development for three cardiac ion channels (hKCNQ1/minK, hCa(v)1.2, and hNa(v)1.5) on the IonWorks Quattro™ system. We demonstrate that these assays can be used as reliable pharmacological profiling tools for cardiac ion channel inhibition to assess compounds for cardiac liability during drug discovery.
Collapse
Affiliation(s)
- Xueying Cao
- Center for Proteomic Chemistry, Novartis Institutes for BioMedical Sciences Inc., Cambridge, Massachusetts 02139, USA
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|