Browsing by Author "Samaisukh Sophasan"
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Item Metadata only Bioactive compounds from Gardenia obtusifolia Roxb. and Gardenia collinsae Craib(Mahidol University. Mahidol University Library and Knowledge Center, 2023) Wilart Popimon; Patoomratana Tuchinda; Vichai Reutrakul; Manat Pohmakotr; Samaisukh SophasanPublication Metadata only Corymine potentiates NMDA-induced currents in Xenopus oocytes expressing NR1a/NR2B glutamate receptors(2005-05-01) Pathama Leewanich; Michihisa Tohda; Hiromitsu Takayama; Samaisukh Sophasan; Hiroshi Watanabe; Kinzo Matsumoto; Srinakharinwirot University; University of Toyama; Chiba University; Mahidol UniversityPrevious studies demonstrated that corymine, an indole alkaloid isolated from the leaves of Hunter zeylanica, dose-dependently inhibited strychnine-sensitive glycine-induced currents. However, it is unclear whether this alkaloid can modulate the function of the N-methyl-D-aspartate (NMDA) receptor on which glycine acts as a co-agonist via strychnine-insensitive glycine binding sites. This study aimed to evaluate the effects of corymine on NR1a/NR2B NMDA receptors expressed in Xenopus oocytes using the two-electrode voltage clamp technique. Corymine significantly potentitated the NMDA-induced currents recorded from oocytes on days 3 and 4 after cRNA injection but it showed no effect when the current was recorded on days 5 and 6. The potentiating effect of corymine on NMDA-induced currents was induced in the presence of a low concentration of glycine (≤0.1 μM). Spermine significantly enhanced the potentiating effect of corymine observed in the oocytes on days 3 and 4, while the NMDA-receptor antagonist 2-amino-5-phosphonopentanone (AP5) and the NMDA-channel blocker 5-methyl-10,11-dihydro-5H-dibenzo[a,d]cyclohepten-5,10- imine (MK-801) reversed the effect of corymine. On the other hand, the nonspecific chloride channel blocker 4,4-di-isothiocyano stilbene-2,2-disulfonoc acid (DIDS) had no effect on the corymine potentiation of NMDA currents. There was no good correlation between corymine- and spermine-induced potentiation of the NMDA-current response in Xenopus oocytes. These results suggest that corymine potentiates the NMDA-induced currents by interacting with a site different from the spermine binding site. © 2005 The Japanese Pharmacological Society.Item Metadata only Cytochrome C release and caspase-3 activation : a possible mechanism of VR-3623-induced apoptosis in human lung cancer LU-1 cell line(Mahidol University. Mahidol University Library and Knowledge Center, 2004) Jeerapa Jarutwanitpong; Kulawee Sujarit; Samaisukh Sophasan; Sukathida UbolPublication Metadata only Cytotoxic and anti-HIV-1 caged xanthones from the resin and fruits of Garcinia hanburyi(2007-01-01) Vichai Reutrakul; Natthinee Anantachoke; Manat Pohmakotr; Thaworn Jaipetch; Samaisukh Sophasan; Chalobon Yoosook; Jittra Kasisit; Chanita Napaswat; Thawatchai Santisuk; Patoomratana Tuchinda; Mahidol University; Thailand Royal Forest DepartmentThree new caged xanthones, 7-methoxydesoxymorellin (1), 2-isoprenylforbesione (2) and 8,8a-epoxymorellic acid (3), together with nine known caged xanthones were isolated from the EtOAc extracts of resin and fruits of Garcinia hanburyi. The structures were determined by spectroscopic methods. Most of the isolated compounds showed significant cytotoxicities against a panel of mammalian cancer cell lines. Compound 3, together with the known compounds desoxymorellin, morellic acid, gambogic acid, hanburin, forbesione and dihydroisomorellin, exhibited anti-HIV-1 activity in the reverse transcriptase (RT) assay while the known compounds desoxygambogenin and dihydroisomorellin were found moderately active in the syncytium assay. This work represents the first report on the anti-HIV-1 activities of caged xanthones. © Georg Thieme Verlag KG Stuttgart.Publication Metadata only Cytotoxic and anti-HIV-1 constituents from leaves and twigs of Gardenia tubifera(2004-02-09) Vichai Reutrakul; Chongkon Krachangchaeng; Patoomratana Tuchinda; Manat Pohmakotr; Thaworn Jaipetch; Chalobon Yoosook; Jittra Kasisit; Samaisukh Sophasan; Kulawee Sujarit; Thawatchai Santisuk; Mahidol University; The Forest Herbarium, Thailand Ministry of Natural Resources and EnvironmentTwo new natural cycloartanes, tubiferolide methyl ester (1) and tubiferaoctanolide (2), together with the known coronalolide (3) and coronalolide methyl ester (4) have been isolated from leaves and twigs of Gardenia tubifera. In addition, a new flavone 5,3′,5′-trihydroxy-7, 4′-dimethoxyflavone (5), five known flavones 6-10 and hexacosyl 4′-hydroxy-trans-cinnamate (11) were also obtained from the same source. The structures were assigned on the basis of spectroscopic methods. Compounds 3, 7, 9, and 10 showed significant cytotoxic activities only in P-388 cell line. Compound 1 was cytotoxic against P-388, KB, Col-2 and Lu-1, while 4 was active in P-388 and BCA-1. Compounds 3 and 4 displayed significant anti-HIV activities in the HIV-1RT assay; compound 7 showed moderate activity in this assay. Compounds 5-10 were also found to be active in theΔTat/RevMC 99 syncytium assay. © 2003 Elsevier Ltd. All rights reserved.Publication Metadata only Cytotoxic and anti-HIV-1 constituents of Gardenia obtusifolia and their modified compounds(2002-09-30) Patoomratana Tuchinda; Wilart Pompimon; Vichai Reutrakul; Manat Pohmakotr; Chalobon Yoosook; Natedao Kongyai; Samaisukh Sophasan; Kulawee Sujarit; Suchart E. Upathum; Thawatchai Santisuk; Mahidol University; Thailand Royal Forest Department5α-Cycloart-24-ene-3,23-dione (1), 5α-cycloart-24-ene-3,16,23-trione (2) and methyl 3,4-seco-cycloart-4(28),24-diene-29-hydroxy-23-oxo-3-oate (3), together with five known flavones 5,7,4′-trihydroxy-3,8-dimethoxyflavone (4), 5,7,4′-trihydroxy-3,8,3′-tri-methoxyflavone (5), 5,7,4′-trihydroxy-3,6,8-trimethoxyflavone (6), 5,4′-dihydroxy-3,6,7,8-tetramethoxyflavone (7) and 5,3′-dihydroxy-3,6,7,8,4′-pentamethoxyflavone (8) have been isolated from the leaves and twigs of Gardenia obtusifolia. The structures were assigned on the basis of spectroscopic methods. Compounds 3-8 and some of the modified compounds showed significant cytotoxic activities in several mammalian cell lines, especially 8 and its diacetate 21 which exhibited potent cytotoxicities (compound 8: P-388 0.05μg/mL, KB 0.09μg/mL, BCA-1 0.63μg/mL, Lu-1 0.09μg/mL, ASK 0.70μg/mL; its diacetate: P-388 0.27μg/mL, KB 0.06μg/mL, BCA-1 0.53μg/mL, Lu-1 0.49μg/mL). It was also found that 5, 8 and 21 showed antimitotic acitivity in the ASK assay. Compounds 2, 4, 6, 7 and some of the modified compounds displayed interesting anti-HIV activity in the syncytium assay, but were inactive or exhibited weak activity in the HIV-1 RT assay; while compound 3 was found to be active in the HIV-1 RT assay (99.9 % inhibition at 200μg/mL), but cytotoxic in the syncytium assay. © 2002 Elsevier Science Ltd. All rights reserved.Publication Metadata only Cytotoxic arylnaphthalide lignan glycosides from the aerial parts of Phyllanthus taxodiifolius(2006-01-01) Patoomratana Tuchinda; Anawat Kumkao; Manat Pohmakotr; Samaisukh Sophasan; Thawatchai Santisuk; Vichai Reutrakul; Mahidol University; Thailand Royal Forest DepartmentThe arylnaphthalide lignan glycosides, taxodiifoloside (1), cleistanthoside A (2), cleistanthin A (3) and cleistanthin A methyl ether (4), together with a triterpene, glochidone (5), have been isolated from the aerial parts of Phyllanthus taxodiifolius. The structures were established using spectral and chemical methods. Compounds 3 and 4, as well as the derivatives 2a and 3a exhibited potent cytotoxic activities with GI50values in the range of 10-7-10-9M in five cultured mammalian cancer cell lines while the new compound 1 showed moderate activity (GI50in the order of 10-6M). Compounds 2 and 5 were inactive in all tested cell lines. © Georg Thieme Verlag KG Stuttgart.Publication Metadata only Cytotoxic Coumarins from Mammea harmandii(2003-11-01) Vichai Reutrakul; Pornsiri Leewanich; Patoomratana Tuchinda; Manat Pohmakotr; Thaworn Jaipetch; Samaisukh Sophasan; Thawatchai Santisuk; Mahidol University; Thailand Royal Forest DepartmentTwo new naturally occurring coumarins, isomesuol (1) and mammearin A (2), together with nine known Mammea coumarins 3-11 were isolated from the EtOAc extract of the leaves and twigs of Mammea harmandii. Coumarins 1, 3 and 4 showed cytotoxicity against a panel of mammalian cancer cell lines. Their structures were determined by spectroscopic methods. The assignments of13C-NMR signals of isomesuol (1), which was isolated for the first time as a natural product, have been revised.Publication Metadata only Cytotoxic styryl-lactones from the leaves and twigs of Polyalthia crassa(2006-12-01) Patoomratana Tuchinda; Bamroong Munyoo; Manat Pohmakotr; Pongchan Thinapong; Samaisukh Sophasan; Thawatchai Santisuk; Vichai Reutrakul; Mahidol University; Thailand Royal Forest DepartmentFour new styryl-lactones, crassalactones A-D (1-4), were isolated from a cytotoxic ethyl acetate-soluble extract of the leaves and twigs of Polyalthia crassa, together with seven known compounds, (+)-3-acetylaltholactone, (+)-altholactone, aristolactam All, cinnamic acid, (+)-goniofufurone, (+)-goniopypyrone, and (+)-howiinol A. Their structures were determined on the basis of spectroscopic methods. The absolute configuration of 1-3 was established by chemical conversions. Single-crystal X-ray analysis and the Mosher ester method were used to confirm the absolute stereochemistry of 4. Cytotoxic evaluation against several mammalian cancer cell lines was performed on all new isolates, aristolactam AII, and the modified (+)-tricinnamate derivative 11 obtained from 1. © 2006 American Chemical Society and American Society of Pharmacognosy.Publication Metadata only Dichapetalin-type triterpenoids and lignans from the aerial parts of Phyllanthus acutissima(2008-04-01) Patoomratana Tuchinda; Jittra Kornsakulkarn; Manat Pohmakotr; Palangpon Kongsaeree; Samran Prabpai; Chalobon Yoosook; Jitra Kasisit; Chanita Napaswad; Samaisukh Sophasan; Vichai Reutrakul; Mahidol UniversityChemical investigation of the aerial parts of Phyllanthus acutissima resulted in the isolation of five new dichapetalin-type triterpenoids, acutissimatriterpenes A-E (1-5), and two new lignans, acutissimalignans A (6) and B (7), along with two known lignans and three known ellagic acid derivatives. The structures of 1-7 were determined mainly on the basis of spectroscopic methods. The compounds obtained were evaluated for cytotoxic and anti-HIV-1 activities. © 2008 American Chemical Society and American Society of Pharmacognosy.Item Metadata only Effect of calcium blockers on renal function after a one day of unilateral ureteral in rats(1989) Samaisukh Sophasan; Surawat Jariyawat; Somchai Pondeenana; Mahidol University. Faculty of Science. Department of PhysiologyPublication Metadata only Effect of chronic K+ deficiency on contractile properties of soleus muscle in rats: Evidence of sex differences(1999-04-26) Pawinee Piyachaturawat; Suparporn Muchimapura; Samaisukh Sophasan; Surawat Jariyawat; Chumpol Pholpramool; Jutamaad Satayavivad; Hitoshi Endou; Mahidol University; Kyorin University1. Alterations in skeletal muscle function of chronically K+-depleted male and female rats were investigated in isolated soleus muscles. 2. By 16 weeks K+ deficiency, plasma K+ concentrations in both male and female rats were reduced to approximately 2 mEq/L, which was accompanied by an approximate 50% reduction in muscle K+ content and a marked increase in muscle Na+ content. These changes were similar in both males and females. 3. Plasma creatine phosphokinase activity progressively increased with time in K+-depleted male rats, whereas only a slight increase was observed in female rats. 4. Maximum isometric twitch tension (Pt) and tetanic tension (Po) of K+-depleted soleus muscles from male rats was markedly suppressed; this was not seen for soleus muscles obtained from female rats. 5. After exposure to insulin in low-K+ solution, the contractile tension of soleus from the K+- depleted male rats was suppressed to a greater extent. 6. All alterations in muscle function during chronic K+ depletion were restored to normal after 2 weeks K+ repletion. 7. The results suggest that there is a preponderance for male over female rats in developing alterations in skeletal muscle function during chronic K+ deficiency. The changes may be associated with abnormalities of muscle membrane permeability and cellular function.Item Metadata only Effect of diuresis on ammonium excretion after unilateral ureteral obstruction in rats(Mahidol University. Mahidol University Library and Knowledge Center, 2024) Sopapan Chaekuntode; Samaisukh Sophasan; Chumpol Pholpramool; Sumalee NimmannitThe present studies indirectly investigated the site of tubular defect that leads to a reduction or ammonium excretion by the damaged kidney after 24 hours of unilateral ureteral obstruction (UUO) in rat. After the released of UUO, the kidney was unable to lower urine pH. The urinary pH of post-obstructed kidney (POK) was 7.28 as compared to 6.11 in the contralateral control kidney (CCK). The fractional bicarbonate excretion of the POR was 10 times the value of the CCK. The rate of ammonium excretion (U(,NH4) and ammonium index (U(,NH4 V/GFR) were both markedly reduced. Thus,the impaired urine acidification was due to reduction in hydrogen ion secretion, bicarbonate reabsorption and ammonium excretion. Induction of diuresis by loop diuretic, furosemide, resulted in increasing ammonium index in both kidneys. However, the Henles loop of the POK may be defective since the degree of the increasing was smaller than those observed in the CCK. Normal saline infusion also lead to increasing ammonium indices in both CCK and POK. However, this increased ammonium index the POK after saline loading was only 37% of the CCK in the normal condition and it was less than the corresponding value after furosemide infusion. Thus, there may be a reduction in ammonium generation and secretion at proximal tubule after UUO. After right nephrectomy (RNx), both methods of diuresis induction resulted in a marked increase in GFR and also ammonium indices. It was suggested that the ammonium index of the POK is in part depending on GFR, which may vary with the number of functioning nephron. Thus, the reduction of ammonium excretion after 24 hrs UUO be due to the reduction in ammonium generation and secretion at proximal tubule. Furthermore, ammonium index is increased irrespect of the methods of diuresis induction which strengthen the conclusion that the defective site of ammonium excretion after 24 hrs UUO may be mainly at proximal tubule and the reabsorption at loop of Henle may not be the major contributing factor in this condition.Item Metadata only Effect of volume expansion on renal blood flow and its autorequlation in the rat(Mahidol University. Mahidol University Library and Knowledge Center, 2024) Apichai Shuprisha; Samaisukh Sophasan; Liangchai Limlomwongse; Chumpol PholpramoolPublication Metadata only Effects of Mg and K deficiency on male and female mice(1998-07-01) Momoko Chiba; Hiromi Watanabe; Atsuko Shinohara; Yutaka Inaba; Samaisukh Sophasan; Hitoshi Endou; Juntendo University; Mahidol University; Kyorin UniversityItem Metadata only Effects of stevioside and steviol on P-aminohippurate transport by isolated perfused rabbit renal proximal tubule(Mahidol University. Mahidol University Library and Knowledge Center, 2023) Promsuk Jutabha; Varanuj Chatsudthipong; Chaivat Toskulkao; Samaisukh Sophasan; Chumpol PholpramoolItem Metadata only Expression of the rat organic anion transporter OAT1 in the yeast Pichia pastoris(Mahidol University. Mahidol University Library and Knowledge Center, 2002) Benjamas Punlungka; Chuenchit Boonchird; Skorn Mongkolsuk; Samaisukh SophasanItem Metadata only Functional characterization of penaeus monodon 5-HT receptor(Mahidol University. Mahidol University Library and Knowledge Center, 2006) Soontaree Petchdee; Samaisukh SophasanPublication Metadata only Functional expression of the rat organic anion transporter 1 (rOAT1) in Saccharomyces cerevisiae(2005-12-30) Suphansa Sawamiphak; Samaisukh Sophasan; Hitoshi Endou; Chuenchit Boonchird; Mahidol University; Kyorin UniversityOrganic anion transporter 1 (OAT1) is localized in the basolateral membrane of the proximal tubule in the kidney and plays an essential role in eliminating a wide range of organic anions, preventing their toxic effects on the body. Structural and functional studies of the transporter would be greatly assisted by inexpensive and rapid expression in the yeast Saccharomyces cerevisiae. The gene encoding rat OAT1 (rOAT1) contains many yeast non-preferred codons at the N-terminus and so was modified by fusion of the favored codon sequence of a hemagglutinin (HA) epitope preceding the start codon. The modified gene was cloned into several yeast expression plasmids, both integrative and multicopy, with either ADH1 promoter or GAL1 promoter in order to find a suitable expression system. Compared with the wild type gene, a substantial increase in rOAT1 expression was achieved by modification in the translational initiation region, suggesting that the codon chosen at the N-terminus influenced its expression. The highest inducible expression of rOAT1 was obtained under GAL1 promoter in 2 μ plasmid. A large fraction of rOAT1 was glycosylated in yeast, unaffected by growth temperature. The recombinant yeast expressing rOAT1 showed an increase in the uptake of p-aminohippurate (PAH) and this showed a positive correlation with rOAT1 expression level. Location of rOAT1 predominantly in the yeast plasma membrane confirmed correct processing. The importance of glycosylation for rOAT1 targeting was also shown. To our knowledge, this is the first successful functional expression of rOAT1 in the yeast S. cerevisiae. © 2005 Elsevier B.V. All rights reserved.Publication Metadata only Human Organic Anion Transporter 4 Is A Renal Apical Organic Anion/Dicarboxylate Exchanger in the Proximal Tubules(2004-03-01) Sophapun Ekaratanawong; Naohiko Anzai; Promsuk Jutabha; Hiroki Miyazaki; Rie Noshiro; Michio Takeda; Yoshikatsu Kanai; Samaisukh Sophasan; Hitoshi Endou; Kyorin University School of Medicine; Faculty of Medicine, Thammasat University; Mahidol UniversityHuman organic anion transporter OAT4 is expressed in the kidney and placenta and mediates high-affinity transport of estrone-3-sulfate (E 1S). Because a previous study demonstrated no trans-stimulatory effects by E1S, the mode of organic anion transport via OAT4 remains still unclear. In the present study, we examined the driving force of OAT4 using mouse proximal tubular cells stably expressing OAT4 (S2 OAT4). OAT4-mediated E1S uptake was inhibited by glutarate (GA) (IC 50: 1.25 mM) and [14C]GA uptake via S2 OAT4 was significantly trans-stimulated by unlabeled GA (5 mM) (P<0.001). [ 3H]E1S uptake via S2 OAT4 was significantly trans-stimulated by preloaded GA (P<0.001) and its [14C]GA efflux was significantly trans-stimulated by unlabeled E1S in the medium (P<0.05). In additon, both the uptake and efflux of [ 14C]p-aminohippuric acid (PAH) and [14C]GA via S 2 OAT4 were significantly trans-stimulated by unlabeled GA or PAH. The immunoreactivities of OAT4 were observed in the apical membrane of proximal tubules along with those of basolateral organic anion/dicarboxylate exchangers such as hOAT1 and hOAT3 in the same tubular population. These results indicate that OAT4 is an apical organic anion/dicarboxylate exchanger and mainly functions as an apical pathway for the reabsorption of some organic anions in renal proximal tubules driven by an outwardly directed dicarboxylate gradient.
