14 results on '"Shun Wan"'
Search Results
2. Inhibitory effect of nonsteroidal anti-inflammatory drugs on adenosine transport in vascular smooth muscle cells
- Author
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Li, Rachel Wai-Sum, Seto, Sai-Wang, Au, Alice Lai-Shan, Kwan, Yiu-Wa, Chan, Shun-Wan, Lee, Simon Ming-Yuen, Tse, Chung-Ming, and Leung, George Pak-Heng
- Published
- 2009
- Full Text
- View/download PDF
3. Role of monoamine oxidases in the exaggerated 5-hydroxytryptamine-induced tension development of human isolated preeclamptic umbilical artery
- Author
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Seto, Sai Wang, Lam, Ho Yeung, Lau, Wing Sze, Au, Alice L.S., Lam, Tsz Yan, Chim, Stephen S.C., Ngai, Sai Ming, Chan, Shun Wan, Leung, Tak Yeung, Yeung, John H.K., Kong, Siu Kai, Leung, George P.H., Lee, Simon M.Y., and Kwan, Yiu Wa
- Published
- 2009
- Full Text
- View/download PDF
4. Comparison of vascular relaxation, lipolysis and glucose uptake by peroxisome proliferator-activated receptor-γ activation in + db/+ m and + db/+ db mice
- Author
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Seto, Sai Wang, Lam, Tsz Yan, Leung, George P.H., Au, Alice L.S., Ngai, Sai Ming, Chan, Shun Wan, and Kwan, Yiu Wa
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- 2007
- Full Text
- View/download PDF
5. Action of anti-tussive drugs on the emetic reflex of Suncus murinus (house musk shrew)
- Author
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Chan, Shun-Wan, Rudd, John A., Lin, Ge, and Li, Ping
- Published
- 2007
- Full Text
- View/download PDF
6. Inhibition of human equilibrative nucleoside transporters by 4-((4-(2-fluorophenyl)piperazin-1-yl)methyl)-6-imino-N-(naphthalen-2-yl)-1,3,5-triazin-2-amine
- Author
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George P.H. Leung, Shun Wan Chan, Chung Ming Tse, Philip Chiu Tsun Tang, Rachel Wai Sum Li, Simon Ming-Yuen Lee, Maggie Pui Man Hoi, Cui Yang, and Yiu Wa Kwan
- Subjects
0301 basic medicine ,Stereochemistry ,Naphthalenes ,Equilibrative nucleoside transporter 2 ,Equilibrative nucleoside transporter 1 ,Piperazines ,Equilibrative Nucleoside Transporter 1 ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,medicine ,Humans ,Equilibrative-Nucleoside Transporter 2 ,Uridine transport ,Pharmacology ,biology ,Adenosine transport ,Triazines ,Biological Transport ,Equilibrative nucleoside transporter ,Adenosine ,Uridine ,Kinetics ,030104 developmental biology ,Gene Expression Regulation ,chemistry ,Biochemistry ,030220 oncology & carcinogenesis ,biology.protein ,Nucleoside ,medicine.drug - Abstract
Equilibrative nucleoside transporters (ENTs) play a crucial role in the transport of nucleoside and nucleoside analogues, which are important for nucleotide synthesis and chemotherapy. In addition, ENTs regulate extracellular adenosine levels in the vicinity of its receptors and hence influence adenosine-related functions. The clinical applications of ENT inhibitors in the treatment of cardiovascular diseases and cancer therapy have been explored in numerous studies. However, all ENT inhibitors to date are selective for ENT1 but not ENT2. In the present study, we investigated the novel compound 4-((4-(2-fluorophenyl)piperazin-1-yl)methyl)-6-imino-N-(naphthalen-2-yl)-1,3,5-triazin-2-amine (FPMINT) as an inhibitor of ENT1 and ENT2. Nucleoside transporter-deficient PK15NTD cells stably expressing ENT1 and ENT2 showed that FPMINT inhibited [3H]uridine and [3H]adenosine transport through both ENT1 and ENT2 in a concentration-dependent manner. The IC50 value of FPMINT for ENT2 was 5-10-fold less than for ENT1, and FPMINT could not be displaced with excess washing. Kinetic studies revealed that FPMINT reduced Vmax of [3H]uridine transport in ENT1 and ENT2 without affecting KM. Therefore, we conclude that FPMINT inhibits ENTs in an irreversible and non-competitive manner. Although already selective for ENT2 over ENT1, further modification of the chemical structure of FPMINT may lead to even better ENT2-selective inhibitors of potential clinical, physiological and pharmacological importance.
- Published
- 2016
7. Comparison of vascular relaxation, lipolysis and glucose uptake by peroxisome proliferator-activated receptor-γ activation in +db/+m and +db/+db mice
- Author
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Seto, Sai Wang, Lam, Tsz Yan, Leung, George P.H., Au, Alice L.S., Ngai, Sai Ming, Chan, Shun Wan, and Kwan, Yiu Wa
- Published
- 2007
- Full Text
- View/download PDF
8. Role of monoamine oxidases in the exaggerated 5-hydroxytryptamine-induced tension development of human isolated preeclamptic umbilical artery
- Author
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Alice L.S. Au, Simon Ming-Yuen Lee, Shun Wan Chan, Ho Yeung Lam, Siu Kai Kong, Tsz Yan Lam, Wing Sze Lau, Stephen S.C. Chim, John H.K. Yeung, Tak Yeung Leung, George P.H. Leung, Sai Wang Seto, Sai-Ming Ngai, and Yiu Wa Kwan
- Subjects
Adult ,Serotonin ,medicine.medical_specialty ,Nitric Oxide Synthase Type III ,Endothelium ,Caveolin 1 ,Gene Expression Regulation, Enzymologic ,Umbilical Arteries ,Preeclampsia ,Young Adult ,Pre-Eclampsia ,Pregnancy ,Enos ,Isometric Contraction ,Internal medicine ,medicine.artery ,medicine ,Humans ,Monoamine Oxidase ,Serotonin Plasma Membrane Transport Proteins ,Pharmacology ,Dose-Response Relationship, Drug ,biology ,business.industry ,Umbilical artery ,biology.organism_classification ,medicine.disease ,Nitric oxide synthase ,Endocrinology ,medicine.anatomical_structure ,Receptors, Serotonin ,Circulatory system ,biology.protein ,Female ,business ,Artery - Abstract
We investigated the role(s) of monoamine oxidases (MAOs) on the altered 5-hydroxytryptamine (5-HT, serotonin)-induced tension development of the isolated umbilical artery of preeclamptic pregnancy of Chinese women. An enhanced 5-HT-induced tension development of the umbilical artery of preeclamptic pregnancy was observed when compared with that of normal pregnancy. The enhanced component of 5-HT-induced tension development was eradicated by clorgyline (a MAO-A inhibitor). Blockade of eNOS (endothelial isoform nitric oxide synthase) (N(omega)-nitro-L-arginine methyl ester), 5-HT transporter (citalopram), 5-HT receptor subtypes (5HT2B, SB 204741; 5-HT2C, RS 102221; 5-HT7, SB 269970), and endothelium denudation of the umbilical artery of normal pregnancy mimicked the enhanced 5-HT-induced tension development as observed in the preeclamptic tissues. In contrast, no apparent changes in 5-HT-induced tension development of the umbilical artery of preeclamptic pregnancy were observed with the same pharmacological manipulations. A decreased protein expression levels of MAO-A and eNOS (no iNOS and MAO-B expression was detected) and no change in caveolin-1 and 5-HT transporter expression were demonstrated in the umbilical artery (endothelium intact) lysate of preeclamptic pregnancy, compared to that of the umbilical artery of normal pregnancy. Thus, in the umbilical artery of preeclamptic pregnancy, a decrease of MAO-A and eNOS protein expression levels are probably associated with, or responsible for, the exaggerated 5-HT-induced tension development.
- Published
- 2009
9. Comparison of vascular relaxation, lipolysis and glucose uptake by peroxisome proliferator-activated receptor-γ activation in +db/+m and +db/+db mice
- Author
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Alice L.S. Au, Tsz Yan Lam, Shun Wan Chan, George P.H. Leung, Sai-Ming Ngai, Sai Wang Seto, and Yiu Wa Kwan
- Subjects
medicine.medical_specialty ,Lipolysis ,Glucose uptake ,Abdominal Fat ,Adipose tissue ,Aorta, Thoracic ,In Vitro Techniques ,Biology ,Nitric oxide ,Mice ,Troglitazone ,chemistry.chemical_compound ,Internal medicine ,Ciglitazone ,Adipocytes ,medicine ,Animals ,Hypoglycemic Agents ,Insulin ,Obesity ,RNA, Messenger ,Chromans ,Pharmacology ,Forskolin ,Pioglitazone ,Lipid Metabolism ,Mice, Mutant Strains ,Mice, Inbred C57BL ,PPAR gamma ,Vasodilation ,Nitric oxide synthase ,Glucose ,Endocrinology ,Diabetes Mellitus, Type 2 ,chemistry ,biology.protein ,Carbohydrate Metabolism ,Female ,Thiazolidinediones ,Endothelium, Vascular ,medicine.drug - Abstract
In this study, we determined the in vitro effect of peroxisome proliferator-activated receptor-gamma (PPAR-gamma) activation on the aortic relaxation, lipolysis and insulin-induced [(3)H]-glucose uptake of the abdominal (omental) adipocytes of the non-diabetic (+db/+m) and obese/diabetic (+db/+db) mice. The expression of PPAR-gamma (mRNA and protein) in aorta and adipose tissues was evaluated and compared. Cumulative application of ciglitazone, pioglitazone and troglitazone (PPAR-gamma agonists) caused a concentration-dependent aortic relaxation (sensitive to 2-chloro-5-nitro-N-phenylbenzamide (GW9662) (1 microM, a selective PPAR-gamma antagonist) and N(omega)-nitro-l-arginine methyl ester (l-NAME) (20 microM, a nitric oxide synthase inhibitor)) with a maximum relaxation of approximately 30% (3 microM) in +db/+m mice, whereas no relaxation was observed in +db/+db mice. All PPAR-gamma agonists examined did not alter the basal lipolysis of both species, but forskolin caused a concentration-dependent lipolysis, with a greater magnitude observed in +db/+m mice. Insulin (0.1 and 1 microM) caused an enhancement of [(3)H]-glucose uptake into adipocytes with a greater magnitude in +db/+m mice. In contrast, none of the PPAR-gamma agonists tested (0.1, 1 and 10 microM) altered the basal and the insulin (0.1 microM)-induced [(3)H]-glucose uptake into adipocytes of both species. In addition, there was no difference in PPAR-gamma expression (mRNA and protein) in the aorta and adipose tissues between the species. In conclusion, our results demonstrate that PPAR-gamma is present in the abdominal (omental) adipose tissue and thoracic aorta. An acute activation of PPAR-gamma produced a small ( approximately 30%) aortic relaxation (nitric oxide/endothelium-dependent) of +db/+m mice. However, all PPAR-gamma agonists examined have no acute effect on lipolysis and the insulin-induced glucose uptake into adipocytes of both +db/+m and +db/+db mice.
- Published
- 2007
10. Inhibition of human equilibrative nucleoside transporters by 4-((4-(2-fluorophenyl)piperazin-1-yl)methyl)-6-imino-N-(naphthalen-2-yl)-1,3,5-triazin-2-amine
- Author
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Tang, Philip C.T., primary, Yang, Cui, additional, Li, Rachel Wai-Sum, additional, Lee, Simon Ming-Yuen, additional, Hoi, Maggie Pui-man, additional, Chan, Shun-Wan, additional, Kwan, Yiu-Wa, additional, Tse, Chung-Ming, additional, and Leung, George Pak-Heng, additional
- Published
- 2016
- Full Text
- View/download PDF
11. In vitro vitamin K(2) and 1α,25-dihydroxyvitamin D(3) combination enhances osteoblasts anabolism of diabetic mice
- Author
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Sai Wang Seto, Christina Chui Wa Poon, Yiu Wa Kwan, Siu Kai Kong, Ho-Pui Ho, Simon Ming-Yuen Lee, Rachel Wai Sum Li, Sai-Ming Ngai, George P.H. Leung, Shun Wan Chan, and Maggie Pui Man Hoi
- Subjects
Male ,medicine.medical_specialty ,Anabolism ,Calcitriol ,Osteoporosis ,Osteocalcin ,chemistry.chemical_element ,Core Binding Factor Alpha 1 Subunit ,Calcium ,Diabetes Mellitus, Experimental ,Mice ,Osteogenesis ,Internal medicine ,medicine ,Vitamin D and neurology ,Animals ,Vitamin D ,Cells, Cultured ,Pharmacology ,Homeodomain Proteins ,Osteoblasts ,biology ,Chemistry ,Vitamin K2 ,Drug Synergism ,Vitamin K 2 ,medicine.disease ,Alkaline Phosphatase ,Activating Transcription Factor 4 ,Endocrinology ,Sp7 Transcription Factor ,biology.protein ,Alkaline phosphatase ,medicine.drug ,Transcription Factors - Abstract
In this study, we evaluated the anabolic effect and the underlying cellular mechanisms involved of vitamin K2 (10 nM) and 1α,25-dihydroxyvitamin D3 (1,25(OH)2D3) (10 nM), alone and in combination, on primary osteoblasts harvested from the iliac crests of C57BL/KsJ lean (+/+) and obese/diabetic (db/db) mice. A lower alkaline phosphatase (ALP) activity plus a reduced expression of bone anabolic markers and bone formation transcription factors (osteocalcin, Runx2, Dlx5, ATF4 and OSX) were consistently detected in osteoblasts of db/db mice compared to lean mice. A significantly higher calcium deposits formation in osteoblasts was observed in lean mice when compared to db/db mice. Co-administration of vitamin K2 (10 nM) and 1,25(OH)2D3 (10 nM) caused an enhancement of calcium deposits in osteoblasts in both strains of mice. Vitamins K2 and 1,25(OH)2D3 co-administration time-dependently (7, 14 and 21 days) increased the levels of bone anabolic markers and bone formation transcription factors, with a greater magnitude of increase observed in osteoblasts of db/db mice. Combined vitamins K2 plus 1,25(OH)2D3 treatment significantly enhanced migration and the re-appearance of surface microvilli and ruffles of osteoblasts of db/db mice. Thus, our results illustrate that vitamins K2 plus D3 combination could be a novel therapeutic strategy in treating diabetes-associated osteoporosis.
- Published
- 2015
12. Relaxation effect of a novel Danshensu/tetramethylpyrazine derivative on rat mesenteric arteries
- Author
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Luchen Shan, George P.H. Leung, Yiu Wa Kwan, Alex Chun Cheung, Rachel Wai Sum Li, King-Ho Cheung, Cui Yang, Zaijun Zhang, Shun Wan Chan, Simon Ming-Yuen Lee, Maggie Pui Man Hoi, and Yuqiang Wang
- Subjects
Male ,Vascular smooth muscle ,Vasodilator Agents ,Pharmacology ,In Vitro Techniques ,Apamin ,Muscle, Smooth, Vascular ,Glibenclamide ,Contractility ,Rats, Sprague-Dawley ,chemistry.chemical_compound ,Medicine ,Tetramethylpyrazine ,Animals ,Vasoconstrictor Agents ,Calcium Signaling ,Enzyme Inhibitors ,Mesenteric arteries ,Dose-Response Relationship, Drug ,business.industry ,Potassium channel blocker ,Iberiotoxin ,Calcium Channel Blockers ,Mesenteric Arteries ,Vasodilation ,medicine.anatomical_structure ,chemistry ,Anesthesia ,Pyrazines ,Lactates ,Calcium ,Calcium Channels ,business ,medicine.drug - Abstract
Danshen (Radix Salviae miltiorrhizae) and ChuanXiong (Ligusticum wallichii) are two traditional herbal medicines commonly used in China for the treatment of cardiovascular diseases. The active components in Danshen and ChuanXiong are Danshensu (DSS, (R)-3, 4-dihydroxyphenyllactic acid) and tetramethylpyrazine (TMP), respectively. In the present study, a new compound named ADTM, which is a conjugation of DSS and TMP, was synthesized and its effect on the contractility of rat mesenteric arteries was examined. The relaxation effect of ADTM on rat mesenteric arteries was studied using myography. The effects of ADTM on Ca(2+) channels were measured by Ca(2+) imaging and patch-clamp techniques. The results showed that ADTM caused a concentration-dependent relaxation of rat mesenteric arteries. This relaxation effect was not affected by the removal of endothelium or inhibitors of nitric oxide synthase, cyclooxygenase, guanylyl cyclase and adenylyl cyclase. Potassium channel blockers including tetraethylammonium, iberiotoxin, apamin, 4-aminopyridine, BaCl2 and glibenclamide also failed to inhibit the relaxation response to ADTM. ADTM inhibited CaCl2-induced contractions and reduced the Ca(2+) influx in isolated mesenteric arterial muscle cells. Our results suggest that ADTM may be a novel relaxing agent. Its mechanism of action involves the direct blockade of voltage-gated Ca(2+) channels in vascular smooth muscle cells, resulting in a decrease in Ca(2+) influx into the cells.
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- 2014
13. Inhibitory effect of nonsteroidal anti-inflammatory drugs on adenosine transport in vascular smooth muscle cells
- Author
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Shun Wan Chan, Chung Ming Tse, Rachel Wai Sum Li, Yiu Wa Kwan, Alice Lai Shan Au, George P.H. Leung, Simon Ming-Yuen Lee, and Sai Wang Seto
- Subjects
Vascular smooth muscle ,Adenosine ,Indomethacin ,Tetrazolium Salts ,Pharmacology ,Muscle, Smooth, Vascular ,Inhibitory Concentration 50 ,Mefenamic Acid ,Piroxicam ,Sulindac ,Indometacin ,Thioinosine ,medicine ,Humans ,Coloring Agents ,Aorta ,Cells, Cultured ,Cell Proliferation ,Adenosine transport ,biology ,Dose-Response Relationship, Drug ,Chemistry ,Anti-Inflammatory Agents, Non-Steroidal ,Temperature ,Adenosine receptor ,digestive system diseases ,Kinetics ,Thiazoles ,Ketoprofen ,biology.protein ,Etodolac ,Cyclooxygenase ,Nucleoside ,medicine.drug - Abstract
It is generally accepted that the clinical efficacy of nonsteroidal anti-inflammatory drugs (NSAIDs) arises mainly from the inhibition of cyclooxygenase (COX). However, more evidence has suggested that certain pharmacological actions of NSAIDs may be mediated by COX-independent mechanisms. The present study investigated the effects of NSAIDs on adenosine uptake in human aortic smooth muscle cells (HASMCs). Among the NSAIDs tested (all at 100 microM), aspirin, ibuprofen and naproxen had no effect on [(3)H]adenosine uptake. Piroxicam inhibited [(3)H]adenosine uptake by 30%, while etodolac, indomethacin, ketoprofen, mefenamic acid and sulindac inhibited [(3)H]adenosine by 13-18%. Sulindac sulfide, an active metabolite of sulindac, inhibited [(3)H]adenosine uptake and [(3)H]nitrobenzylmercaptopurine ribonucleoside (NBMPR) binding of HASMCs with IC(50) values of 40.67+/-4.82 and 24.19+/-3.76 muM, respectively. Kinetic studies revealed that sulindac sulfide was a competitive inhibitor of adenosine uptake. Using the nucleoside-transporter-deficient PK15NTD cells that stably express equilibrative nucleoside transport (ENT) 1 and ENT2, it was found that the inhibitory effect of sulindac sulfide on ENT1 was greater than that on ENT2. Sulindac sulfide increased the extracellular adenosine level. In addition, it inhibited the proliferation of HASMCs and this anti-proliferative effect could be abolished by adenosine A(2B) receptor antagonist. Our results suggest that sulindac sulfide may exert pharmacological effects through the inhibition of adenosine uptake, which modulates the availability of adenosine in the vicinity of adenosine receptors.
- Published
- 2008
14. Action of anti-tussive drugs on the emetic reflex of Suncus murinus (house musk shrew)
- Author
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John A. Rudd, Ge Lin, Shun Wan Chan, and Ping Li
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medicine.medical_specialty ,Baclofen ,Nicotine ,Copper Sulfate ,medicine.drug_class ,Motion Sickness ,Vomiting ,Scopolamine ,Pharmacology ,chemistry.chemical_compound ,Internal medicine ,Reflex ,medicine ,Animals ,Neurotransmitter ,Analysis of Variance ,biology ,Dose-Response Relationship, Drug ,Codeine ,Shrews ,Diphenhydramine ,Muscle relaxant ,Suncus ,biology.organism_classification ,Antitussive Agents ,Disease Models, Animal ,Endocrinology ,chemistry ,Opioid ,Antiemetics ,Female ,medicine.drug ,Cevanes - Abstract
The cough and emetic reflexes involve a synchronized firing of motor neurones involved in respiratory control. Tachykinin NK1 receptor antagonists and 5-HT1A receptor agonists are examples of centrally acting drugs that reduce cough and emesis. In the present studies, therefore, we examined the possibility that other classes of drugs known to reducing cough have anti-emetic properties to prevent emesis induced by diverse challenges. We examined the potential of codeine (1-10 mg/kg), baclofen (1-10 mg/kg), scopolamine (0.3-10 mg/kg), diphenhydramine (1-10 mg/kg), imperialine (1-30 mg/kg) and verticine (0.3-3 mg/kg) to inhibit emesis induced by nicotine (5 mg/kg, s.c.), copper sulphate (120 mg/kg, intragastric), and provocative motion (4 cm horizontal displacement, delivered at 1 Hz) in Suncus murinus (house musk shrew). Only codeine had broad inhibitory properties (P0.05) to antagonize emesis induced by all challenges with ID50 values ranging from 1.2 to 2.3 mg/kg. Baclofen antagonized emesis induced by nicotine (maximum reduction was 44.9%, P0.05) and motion (maximum reduction was 97.3%, P0.01), but potentiated copper sulphate-induced emesis (maximum potentiation was 73.0%, P0.05). Scopolamine antagonized copper sulphate-induced emesis (maximum reduction was 61.2%, P0.05) and imperialine antagonized nicotine-induced emesis (maximum reduction was 30.2%, P0.01), but verticine potentiated motion-induced emesis (maximum potentiation was 60.0%, P0.05). Diphenhydramine did not significantly reduce emesis induced by any of the challenges (P0.05). In conclusion, codeine has broad inhibitory anti-emetic actions but a known ability to reduce coughing does not necessarily predict broad inhibitory anti-emetic properties.
- Published
- 2006
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