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Zhao X, Wang H, Yang Y, Gou Y, Wang Z, Yang D, Li C. Protective Effects of Silymarin Against D-Gal/LPS-Induced Organ Damage and Inflammation in Mice. Drug Des Devel Ther 2021; 15:1903-1914. [PMID: 33976540 PMCID: PMC8106468 DOI: 10.2147/dddt.s305033] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2021] [Accepted: 04/10/2021] [Indexed: 01/26/2023] Open
Abstract
AIM Silymarin contains various flavonoids and exhibits antioxidative, anti-inflammatory, and anticancer effects, in addition to other pharmacological properties. This study explored the alleviating effect of silymarin on multiple-organ damage induced by D-galactose/lipopolysaccharide in Kunming mice. METHODS Kunming mice were injected intraperitoneally with D-galactose (30 mg/kg·BW)/LPS (3 μg/kg·BW) and then treated using silymarin with different doses (75 mg/kg·bw and 150 mg/kg·bw) via intragastric administration. Changes in organ indexes, pathological changes, liver-function index, biochemical indexes, molecular biological indexes, and genes related to the oxidation and inflammation of main organs were evaluated. RESULTS After the mice were treated with silymarin, their body weight showed no significant change, and the liver, kidney, and lung indexes of the treated mice were higher than those of the model group; meanwhile, the corresponding histopathological formation was reduced. Compared with the model group, the silymarin-treated group showed reductions in ALT, AST, and liver function indexes in the mouse serum. Silymarin treatment also increased the SOD, CAT, GSH, GSH-Px, T-AOC, IL-10, and IL-12 levels, as well as reduced the MDA, NO, IL-6, IL-1β, TNF-α, IFN-γ levels in the mouse serum and liver tissues. In addition, quantitative polymerase chain reaction analysis indicated that the mRNA expression levels of SOD1, SOD2, CAT, GSH-Px, IL-10, Nrf2, HO-1, NQO1, Trx, and IκB-α were higher in the liver tissue of the silymarin-treated mice than in those of the model group; meanwhile, the mRNA expression levels of IL-6, IL-1β, TNF-α, IFN-γ, NF-κB, NLRP3, COX2, and p38 were lower than those in the model group. CONCLUSION Silymarin, which exhibits antioxidative and anti-inflammatory effects, can alleviate the liver, lung, and kidney damage induced by D-galactose/lipopolysaccharide. High-dose (150 mg/kg·bw) silymarin can more effectively inhibit organ damage, compared with low-dose silymarin (75 mg/kg·bw) in Kunming mice.
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Affiliation(s)
- Xin Zhao
- Chongqing Collaborative Innovation Center for Functional Food, Chongqing University of Education, Chongqing, 400067, People’s Republic of China
- Chongqing Engineering Research Center of Functional Food, Chongqing University of Education, Chongqing, 400067, People’s Republic of China
- Chongqing Engineering Laboratory for Research and Development of Functional Food, Chongqing University of Education, Chongqing, 400067, People’s Republic of China
| | - Haoxiang Wang
- Department of Neurology, Second Affiliated Hospital of Army Medical University, Chongqing, 400037, People’s Republic of China
| | - Yue Yang
- Chongqing Collaborative Innovation Center for Functional Food, Chongqing University of Education, Chongqing, 400067, People’s Republic of China
- College of Biological and Chemical Engineering, Chongqing University of Education, Chongqing, 400067, People’s Republic of China
| | - Yuting Gou
- Chongqing Collaborative Innovation Center for Functional Food, Chongqing University of Education, Chongqing, 400067, People’s Republic of China
- College of Biological and Chemical Engineering, Chongqing University of Education, Chongqing, 400067, People’s Republic of China
| | - Zhiying Wang
- School of Pharmacy, Heilongjiang University of Traditional Chinese Medicine, Harbin, 150040, People’s Republic of China
| | - Dingyi Yang
- Key Laboratory for Biorheological Science and Technology of Ministry of Education (Chongqing University), Chongqing University Cancer Hospital & Chongqing Cancer Institute & Chongqing Cancer Hospital, Chongqing, 400044, People’s Republic of China
| | - Chong Li
- Chongqing Collaborative Innovation Center for Functional Food, Chongqing University of Education, Chongqing, 400067, People’s Republic of China
- Chongqing Engineering Research Center of Functional Food, Chongqing University of Education, Chongqing, 400067, People’s Republic of China
- Chongqing Engineering Laboratory for Research and Development of Functional Food, Chongqing University of Education, Chongqing, 400067, People’s Republic of China
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Affiliation(s)
- Ayaz Anwar
- Department of Biological Sciences, School of Science and Technology, Sunway University, Subang Jaya, Selangor, Malaysia
- * E-mail:
| | - Naveed A. Khan
- Department of Biological Sciences, School of Science and Technology, Sunway University, Subang Jaya, Selangor, Malaysia
| | - Ruqaiyyah Siddiqui
- Department of Biological Sciences, School of Science and Technology, Sunway University, Subang Jaya, Selangor, Malaysia
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Çoban J, Doğan-Ekici I, Aydın AF, Betül-Kalaz E, Doğru-Abbasoğlu S, Uysal M. Blueberry treatment decreased D-galactose-induced oxidative stress and brain damage in rats. Metab Brain Dis 2015; 30:793-802. [PMID: 25511550 DOI: 10.1007/s11011-014-9643-z] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/28/2014] [Accepted: 12/05/2014] [Indexed: 12/29/2022]
Abstract
D-galactose (GAL) causes aging-related changes and oxidative stress in the organism. We investigated the effect of whole fresh blueberry (BB) (Vaccinium corymbosum L.) treatment on oxidative stress in age-related brain damage model. Rats received GAL (300 mg/kg; s.c.; 5 days per week) alone or together with 5 % (BB1) and 10 % (BB2) BB containing chow for two months. Malondialdehyde (MDA),protein carbonyl (PC) and glutathione (GSH) levels, and Cu Zn-superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and glutathione transferase (GST) activities as well as acetylcholinesterase (AChE) activities were determined. Expressions of B cell lymphoma-2 (Bcl-2), Bax and caspase-3 were also evaluated in the brain by immunohistochemistry. MDA and PC levels and AChE activity increased, but GSH levels, SOD and GSH-Px activities decreased together with histopathological structural damage in the brain of GAL-treated rats. BB treatments, especially BB2 reduced MDA and PC levels and AChE activity and elevated GSH levels and GSH-Px activity. BB1 and BB2 treatments diminished apoptosis and ameliorated histopathological findings in the brain of GAL-treated rats. These results indicate that BB partially prevented the shift towards an imbalanced prooxidative status and apoptosis together with histopathological amelioration by acting as an antioxidant (radical scavenger) itself in GAL-treated rats.
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Affiliation(s)
- Jale Çoban
- Department of Biochemistry, Yeditepe University Medical Faculty, Kayışdağı, Istanbul, Turkey
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Kadam RU, Bergmann M, Hurley M, Garg D, Cacciarini M, Swiderska MA, Nativi C, Sattler M, Smyth AR, Williams P, Cámara M, Stocker A, Darbre T, Reymond JL. A glycopeptide dendrimer inhibitor of the galactose-specific lectin LecA and of Pseudomonas aeruginosa biofilms. Angew Chem Int Ed Engl 2011; 50:10631-5. [PMID: 21919164 PMCID: PMC3262149 DOI: 10.1002/anie.201104342] [Citation(s) in RCA: 131] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2011] [Revised: 08/17/2011] [Indexed: 11/26/2022]
Affiliation(s)
- Rameshwar U Kadam
- Department of Chemistry and Biochemistry, University of BerneFreiestrasse 3, 3012 Berne (Switzerland)
| | - Myriam Bergmann
- Department of Chemistry and Biochemistry, University of BerneFreiestrasse 3, 3012 Berne (Switzerland)
| | - Matthew Hurley
- School of Molecular Medical Sciences, University of NottinghamNottingham NG7 2UH (UK)
- School of Clinical Sciences, University of NottinghamNottingham NG7 2UH (UK)
| | - Divita Garg
- Institute of Structural Biology, Helmholtz Zentrum München and Center for Integrated Protein Science Munich, Departement Chemie, Technische Universität MünchenLichtenbergstrasse 4, 85747 Garching (Germany)
| | - Martina Cacciarini
- Dipartimento di Chimica, Polo Scientifico e Tecnologico, Universita' degli Studi di FirenzeVia della Lastruccia 3, 13, 50019 Sesto Fiorentino—Firenze (Italy)
| | - Magdalena A Swiderska
- Department of Chemistry and Biochemistry, University of BerneFreiestrasse 3, 3012 Berne (Switzerland)
| | - Cristina Nativi
- Dipartimento di Chimica, Polo Scientifico e Tecnologico, Universita' degli Studi di FirenzeVia della Lastruccia 3, 13, 50019 Sesto Fiorentino—Firenze (Italy)
| | - Michael Sattler
- Institute of Structural Biology, Helmholtz Zentrum München and Center for Integrated Protein Science Munich, Departement Chemie, Technische Universität MünchenLichtenbergstrasse 4, 85747 Garching (Germany)
| | - Alan R Smyth
- School of Clinical Sciences, University of NottinghamNottingham NG7 2UH (UK)
| | - Paul Williams
- School of Molecular Medical Sciences, University of NottinghamNottingham NG7 2UH (UK)
| | - Miguel Cámara
- School of Molecular Medical Sciences, University of NottinghamNottingham NG7 2UH (UK)
| | - Achim Stocker
- Department of Chemistry and Biochemistry, University of BerneFreiestrasse 3, 3012 Berne (Switzerland)
| | - Tamis Darbre
- Department of Chemistry and Biochemistry, University of BerneFreiestrasse 3, 3012 Berne (Switzerland)
| | - Jean-Louis Reymond
- Department of Chemistry and Biochemistry, University of BerneFreiestrasse 3, 3012 Berne (Switzerland)
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Ji LX, Shen N, Li CN, Liu Q, Huan Y, Shen ZF. [Inhibition effect of epalrestat on rat lens osmotic expansion]. Yao Xue Xue Bao 2009; 44:1107-1111. [PMID: 20055132] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Epalrestat is the unique aldose reductase inhibitor on the market, which was mainly used for the diabetic neuropathy. Lenses osmotic expansion could be induced by galactose to mimic the pathological process of diabetic cataract in vitro. In present study, we mainly investigated whether epalrestat possesses inhibitory effect on the lens osmotic expansion. The results indicated that epalrestat could not only markedly inhibit rat lens osmotic expansion in vitro, but also significantly reduced the high expression of the osmotic expansion-related genes such as AR and AQP1 in mRNA and protein levels. The findings may provide an important reference to epalrestat in the clinical application for the treatment of diabetic cataract.
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Affiliation(s)
- Li-Xia Ji
- Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China
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Ma YH, Liu AJ, Zhang GR, Lang J. [Effect of seleno-arginine on cellular immunological function in D-gal aging mice]. Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi 2007; 23:1126-1129. [PMID: 18062883] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
AIM To study the effect of seleno-argnine on cellular immunological function in D-gal aging mice. METHODS The mice were divided into normal group, model group, low seleno-argnine group(L-SeArg) and high seleno-argnine group (H-SeArg). D-galactose induced aging model was set up by s.c. injection for 42 days, i.g. method was used to add Seleno-argnine. Spleen index(SI) and thymus index (TI) were measured. The ability of Spleen cell multiplication and NK cell killing activity were determined by MTT colorimetry. The changes of CD40 and CD40L expression were observed by immunofluorescent assay. RESULTS Compared with the model mice, seleno-argnine increased spleen index and thynus index, enhanced the ability of spleen cell multiplication, enhanced the expression of CD40 and CD40L, and accelerated the NK cell killing activity. Between the two seleno-argnine groups, the effect of L-SeArg on cellular immunological function was more obvious in D-gal aging mice.The result were statistic ally significantly compared with the model mice(P<0.01). CONCLUSION D-gal injection can decrease the cellular immunological function of mice. Seleno-argnine can activate immune cells, enhance the cellular immunological function of mice, reduce the toxic effect of D-gal and delay the aging process.
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Affiliation(s)
- Yan-Hong Ma
- College of Food Engineering and Biotechnology, Tianjin University of Science and Technology, Tianjin 300457, China.
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Kador PF, Betts D, Wyman M, Blessing K, Randazzo J. Effects of topical administration of an aldose reductase inhibitor on cataract formation in dogs fed a diet high in galactose. Am J Vet Res 2007; 67:1783-7. [PMID: 17014334 DOI: 10.2460/ajvr.67.10.1783] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
OBJECTIVE To determine effects of a topical formulation of an aldose reductase inhibitor (ARI) on the development of sugar cataracts in dogs fed a diet high in galactose. Animals-Ten 6-month old Beagles. PROCEDURES Dogs were fed a diet containing 30% galactose, and after 16 weeks, 6 dogs were treated topically with a proprietary ARI formulation and 4 dogs were treated with a placebo. Cataract formation was monitored by means of slit-lamp biomicroscopy and fundus photography. Dogs were euthanized after 10 weeks of treatment, and lenses were evaluated for degree of opacity, myo-inositol and galactitol concentrations, and concentration of the ARI. RESULTS All dogs developed bilateral cortical opacities dense enough to result in a decrease in the tapetal reflex after being fed the galactose-containing diet for 16 weeks. Administration of the ARI arrested further development of cataract formation. In contrast, cataracts in the vehicle-treated dogs progressed over the 10-week period to the mature stage. Evaluation of the isolated lenses after 26 weeks of galactose feeding indicated that lenses from treated dogs were significantly less optically dense than lenses from control dogs. Lenticular myo-inositol concentration was significantly higher in the treated than in the control dogs. CONCLUSIONS AND CLINICAL RELEVANCE Results suggest that topical application of a proprietary ARI formulation may arrest or reverse the development of sugar cataracts in dogs fed a diet high in galactose. This suggests that this ARI formulation may be beneficial in maintaining or improving functional vision in diabetic dogs with early lens opacities.
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Affiliation(s)
- Peter F Kador
- College of Pharmacy, University of Nebraska Medical Center, Omaha, NE 68198, Therapeutic Vision Inc, 11778 Whitmore S, Omaha, NE 68142, USA
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Amador P, García-Herrera J, Marca MC, de la Osada J, Acín S, Navarro MA, Salvador MT, Lostao MP, Rodríguez-Yoldi MJ. Inhibitory effect of TNF-α on the intestinal absorption of galactose. J Cell Biochem 2007; 101:99-111. [PMID: 17177295 DOI: 10.1002/jcb.21168] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Sepsis is a systemic response to infection in which toxins, such as bacterial lipopolysaccharide (LPS), stimulate the production of inflammatory mediators like the cytokine tumor necrosis factor alpha (TNF-alpha). Previous studies from our laboratory have revealed that LPS inhibits the intestinal absorption of L-leucine and D-fructose in rabbit when it was intravenously administered, and that TNF-alpha seems to mediate this effect on amino acid absorption. To extend this work, the present study was designed to evaluate the possible effect of TNF-alpha on D-galactose intestinal absorption, identify the intracellular mechanisms involved and establish whether this cytokine mediates possible LPS effects. Our findings indicate that TNF-alpha decreases D-galactose absorption both in rabbit intestinal tissue preparations and brush-border membrane vesicles. Western blot analysis revealed reduced amounts of the Na+/glucose cotransporter (SGLT1) protein in the plasma membrane attributable to the cytokine. On the contrary, TNF-alpha increased SGLT1 mRNA levels. Specific inhibitors of the secondary messengers PKC, PKA, the MAP kinases p38 MAP, JNK, MEK1/2 as well as the proteasome, diminished the TNF-alpha-evoked inhibitory effect. LPS inhibition of the uptake of the sugar was blocked by a TNF-alpha antagonist. In conclusion, TNF-alpha inhibits D-galactose intestinal absorption by decreasing the number of SGLT1 molecules at the enterocyte plasma membrane through a mechanism in which several protein-like kinases are involved.
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Affiliation(s)
- P Amador
- Department of Pharmacology and Physiology, Physiology Unit, Veterinary Faculty, University of Zaragoza, E-50013 Zaragoza, Spain
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Cui X, Zuo P, Zhang Q, Li X, Hu Y, Long J, Packer L, Liu J. Chronic systemic D-galactose exposure induces memory loss, neurodegeneration, and oxidative damage in mice: protective effects of R-alpha-lipoic acid. J Neurosci Res 2006; 84:647-54. [PMID: 16710848 DOI: 10.1002/jnr.20899] [Citation(s) in RCA: 194] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Chronic systemic exposure of mice, rats, and Drosophila to D-galactose causes the acceleration of senescence and has been used as an aging model. The underlying mechanism is yet unclear. To investigate the mechanisms of neurodegeneration in this model, we studied cognitive function, hippocampal neuronal apoptosis and neurogenesis, and peripheral oxidative stress biomarkers, and also the protective effects of the antioxidant R-alpha-lipoic acid. Chronic systemic exposure of D-galactose (100 mg/kg, s.c., 7 weeks) to mice induced a spatial memory deficit, an increase in cell karyopyknosis, apoptosis and caspase-3 protein levels in hippocampal neurons, a decrease in the number of new neurons in the subgranular zone in the dentate gyrus, a reduction of migration of neural progenitor cells, and an increase in death of newly formed neurons in granular cell layer. The D-galactose exposure also induced an increase in peripheral oxidative stress, including an increase in malondialdehyde, a decrease in total anti-oxidative capabilities (T-AOC), total superoxide dismutase (T-SOD), and glutathione peroxidase (GSH-Px) activities. A concomitant treatment with lipoic acid ameliorated cognitive dysfunction and neurodegeneration in the hippocampus, and also reduced peripheral oxidative damage by decreasing malondialdehyde and increasing T-AOC and T-SOD, without an effect on GSH-Px. These findings suggest that chronic D-galactose exposure induces neurodegeneration by enhancing caspase-mediated apoptosis and inhibiting neurogenesis and neuron migration, as well as increasing oxidative damage. In addition, D-galactose-induced toxicity in mice is a useful model for studying the mechanisms of neurodegeneration and neuroprotective drugs and agents.
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Affiliation(s)
- Xu Cui
- Institute of Gerontology and Geriatrics, Chinese PLA General Hospital, Beijing, People's Republic of China
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Cui X, Zuo P, Zhang Q, Li X, Hu Y, Long J, Packer L, Liu J. Chronic systemic D-galactose exposure induces memory loss, neurodegeneration, and oxidative damage in mice: protective effects of R-alpha-lipoic acid. J Neurosci Res 2006; 83:1584-90. [PMID: 16555301 DOI: 10.1002/jnr.20845] [Citation(s) in RCA: 148] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Chronic systemic exposure of D-galactose to mice, rats, and Drosophila causes the acceleration of senescence and has been used as an aging model. However, the underlying mechanism is as yet unclear. To investigate the mechanisms of neurodegeneration in this model, we studied cognitive function, hippocampal neuronal apoptosis and neurogenesis, and peripheral oxidative stress biomarkers and also the protective effects of the antioxidant R-alpha-lipoic acid. Chronic systemic exposure of mice to D-galactose (100 mg/kg, s.c., 7 weeks) induced a spatial memory deficit, an increase in cell karyopyknosis, apoptosis, and caspase-3 protein levels in hippocampal neurons, a decrease in the number of new neurons in the subgranular zone in the dentate gyrus, a reduction of migration of neural progenitor cells, and an increase in death of newly formed neurons in the granular cell layer. The D-galactose exposure also induced an increase in peripheral oxidative stress, including an increase in malondialdehyde and decreases in total antioxidative capabilities (T-AOC), total superoxide dismutase (T-SOD), and glutathione peroxidase (GSH-Px) activities. A concomitant treatment with lipoic acid ameliorated cognitive dysfunction and neurodegeneration in the hippocampus and also reduced peripheral oxidative damage by decreasing malondialdehyde and increasing T-AOC and T-SOD, without an effect on GSH-Px. These findings suggest that chronic D-galactose exposure induces neurodegeneration by enhancing caspase-mediated apoptosis and inhibiting neurogenesis and neuron migration, as well as increasing oxidative damage. In addition, D-galactose-induced toxicity in mice is a useful model for studying the mechanisms of neurodegeneration and neuroprotective drugs and agents.
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Affiliation(s)
- Xu Cui
- Institute of Gerontology and Geriatrics, Chinese PLA General Hospital, Beijing, People's Republic of China
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Lv JH, Zhang SP, Shen FH, Pan JQ, Tan HR. [Improvement effects of puerarin on glycated brain damages in rats induced by D-galactose]. Zhongguo Zhong Yao Za Zhi 2006; 31:1184-7. [PMID: 17048591] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
OBJECTIVE To observe the improvement effects of puerarin on glycated brain damages in rat model induced by D-galactose. METHOD The model rats of protein glycation were induced by intraperitoneal administration of D-galactose (150 mg x kg(-1) x d(-1)) for 8 weeks, and all rats were treated with puerarin (high dose 300 mg x kg(-1), middle dose 150 mg x kg(-1), low dose 75 mg x kg(-1)) for 6 weeks. The activity of aldose reductase in red blood cells, the amount of glycated products (fructosamine in serum, glycohaemoglobin, advanced glycation end-products) and AGEs in brain tissue, calcium ion in brain cells were measured. Moreover, mitochondria in brain hippocampus cells were observed under electronic microscope. RESULT High dose and middle dose of puerarin can decrease the activity of aldose reductase in red blood cells (P < 0.01), and inhibit the formation of glycation products significantly in model rats induced by D-galactose (P < 0.01). Also, puerarin can decrease the content of AGEs in brain and the level of calcium ions in brain cells (P < 0.05, P < 0.01), and decrease lesions degree in mitochondria in brain hippocampus cells. CONCLUSION Puerarin can produce the protective effects on glycated brain damages through inhibiting the glycation reaction in rats induced by D-galactose.
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Affiliation(s)
- Jun-Hua Lv
- School of Pharmacy, Jinan University, Guangzhou 510632, China.
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Mizisin AP, Kalichman MW, Bache M, Dines KC, DiStefano PS. NT-3 attenuates functional and structural disorders in sensory nerves of galactose-fed rats. J Neuropathol Exp Neurol 1998; 57:803-13. [PMID: 9737543 DOI: 10.1097/00005072-199809000-00001] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
The present study investigated the effect of NT-3, a neurotrophin expressed in nerve and skeletal muscle, on myelinated fiber disorders of galactose-fed rats. Adult, female Sprague-Dawley rats were fed diets containing complete micronutrient supplements and either 0% D-galactose (control) or 40% D-galactose. Treated controls received 20 mg/kg NT-3 and treated galactose-fed rats received 1, 5, or 20 mg/kg NT-3 three times per week by subcutaneous injections. After 2 months, sciatic and saphenous sensory nerve conduction velocity (SNCV) and sciatic motor nerve conduction velocity (MNCV) were measured and the sciatic, sural, peroneal and saphenous nerves and dorsal and ventral roots processed for light microscopy. Treatment of control animals with NT-3 had no effect on any functional or structural parameter. Compared to control values, galactose feeding induced a sensory and motor nerve conduction deficit and a reduction in axonal caliber. Treatment with 5 and 20 mg/kg NT-3 ameliorated deficits in sciatic and saphenous SNCV in galactose-fed rats but had no effect on the MNCV deficit. NT-3 treatment also attenuated the decrease in mean axonal caliber in the dorsal root and sural nerve but not in the saphenous nerve, ventral root and peroneal nerve. These observations show that NT-3 can selectively attenuate the sensory conduction deficit of galactose neuropathy in a dose-dependent manner that depends only in part on restoration of axonal caliber of large-fiber sensory neurons.
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Affiliation(s)
- A P Mizisin
- Department of Pathology, University of California, San Diego, the Veterans Administration Medical Center, La Jolla 92093-0612, USA
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Soong CJ, Kain KC, Abd-Alla M, Jackson TF, Ravdin JI. A recombinant cysteine-rich section of the Entamoeba histolytica galactose-inhibitable lectin is efficacious as a subunit vaccine in the gerbil model of amebic liver abscess. J Infect Dis 1995; 171:645-51. [PMID: 7876611 DOI: 10.1093/infdis/171.3.645] [Citation(s) in RCA: 53] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
The 170-kDa subunit of the galactose-inhibitable adherence lectin of Entamoeba histolytica mediates attachment to colonic mucins and host cells. The DNA fragment encoding the 170-kDa subunit was produced by polymerase chain reaction (PCR) and divided into four sections by restriction endonucleases. The third section (designated LC3, base pairs 2273-3397) encodes a cysteine-rich fusion protein that was recognized by adherence-inhibitory anti-lectin monoclonal antibodies and serum antibodies from 95% of subjects with amebic liver abscess. Immunization of gerbils with purified recombinant LC3-encoded protein (10 micrograms) with Titermax adjuvant elicited a high-titer serum anti-LC3 IgG antibody response and protective immunity against intrahepatic challenge with 0.5 x 10(6) virulent axenic trophozoites (strain HM1:IMSS; 71% vaccine efficacy, P < .01). In summary, a recombinant cysteine-rich portion of the 170-kDa lectin subunit was highly antigenic, immunogenic, and effective as a subunit vaccine in an experimental animal model of amebic liver abscess.
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Affiliation(s)
- C J Soong
- Department of Medicine, Case Western Reserve University, Cleveland, Ohio
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Abstract
The aim of the present work was to study whether zinc chloride added to the drinking water of rabbits affected the intestinal absorption of D-galactose and the activity of sucrase in the jejunum. The results showed that zinc decreased D-galactose absorption in the jejunal tissue. The effect appeared to be due mainly to an action on the active transport of the sugar by the mucosal border of the intestinal epithelium, because the zinc seemed not to affect its diffusion across the intestinal epithelium. Zinc was also shown to inhibit the (Na(+)-Ka+)-ATPase activity of the enterocyte, which might explain the inhibition of the Na(+)-dependent transport of D-galactose. Nevertheless, a possible direct action of the zinc ion on the Na(+)-dependent carrier cannot be discounted. Zinc did not alter the activity of sucrase in the jejunum of the rabbit.
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Abd-Alla MD, Jackson TF, Gathiram V, el-Hawey AM, Ravdin JI. Differentiation of pathogenic Entamoeba histolytica infections from nonpathogenic infections by detection of galactose-inhibitable adherence protein antigen in sera and feces. J Clin Microbiol 1993; 31:2845-50. [PMID: 8263165 PMCID: PMC266142 DOI: 10.1128/jcm.31.11.2845-2850.1993] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
We determined whether epitope-specific monoclonal antibodies to the galactose-inhibitable adherence protein (GIAP) of Entamoeba histolytica could be used in an enzyme-linked immunosorbent assay (ELISA) to detect antigen in serum and feces and differentiate between nonpathogenic zymodemes and the potentially invasive pathogenic organisms that require treatment. Overall, 57% of subjects from Cairo, Egypt, with symptomatic intestinal amebiasis and 42% with asymptomatic infection possessed GIAP antigen in their sera, whereas 4% of uninfected controls or subjects with other parasitic infections possessed GIAP antigen in their sera (P < 0.001). In subjects from Durban, South Africa, only 6% of uninfected controls or those with nonpathogenic E. histolytica infection were positive for GIAP in serum, whereas 3 of 4 with asymptomatic pathogenic intestinal infection and 75% with amebic liver abscess were positive for GIAP in serum. Fifteen stool samples from patients with intestinal amebiasis were available for study; all had a positive ELISA result for fecal GIAP antigen. Epitope-specific monoclonal antibodies identified 8 of 15 subjects with fecal antigen from pathogenic strains. Seven of those eight subjects had adherence protein antigen in their sera, whereas none of seven with apparent nonpathogenic E. histolytica infection had adherence protein antigen in their sera. In summary, we were able to detect E. histolytica adherence protein antigen directly in serum and fecal samples by ELISA. The presence of amebic antigen in serum demonstrated 94% specificity for pathogenic E. histolytica infection, and amebic antigen is present during asymptomatic intestinal infection. In conjunction with antibody detection, this method should be very useful in the diagnosis and management of intestinal amebiasis.
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Abstract
Intact lenses from New Zealand white rabbits were incubated in tissue culture media containing either 5 mM glucose or 5 mM glucose plus 30 mM galactose. The standard media did not contain taurine. Lenses were also cultured in a third medium containing 30 mM galactose plus 0.2 mM taurine. The frequency of cataract formation was evaluated as a function of the culture media. One lens (1/10), in media containing 5 mM glucose, developed a lenticular opacification during a 72-h incubation. Lenses (12/15) incubated in 30 mM galactose, without taurine, developed cataracts; fewer lenses (2/13) exposed to 30 mM galactose plus 0.2 mM taurine developed cataracts (p < 0.005). Galactose cataracts have been associated with lens edema attributed to the osmotic stress of tissue polyol (galactitol) accumulation. The water content of the noncataractous and cataractous lenses in this experiment did not differ. Lens edema, therefore, was not thought to be important in cataract pathogenesis. Taurine, an organic osmolyte was lower (5.1 +/- 1.5 mumol/g protein) in cataractous lenses than in control lenses (10.0 +/- 1.0 mumol/g protein). Malondialdehyde, an indicator of lipid peroxidation, was higher (36.6 +/- 5.0 mumol/g protein) in lens-containing opacifications than in noncataractous lenses (10.1 +/- 1.9 mumol/gm protein) (p < 0.01). The levels of malondialdehyde suggest that lipid peroxidation was increased in the process of sugar cataractogenesis. The malondialdehyde content of all the lenses correlated inversely (r = -0.53, p < 0.01) with the coincident lens taurine levels. Taurine appears to protect the lens against the development of sugar cataracts; its inverse relationship with lens malondialdehyde suggests this is an antioxidant effect.
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Affiliation(s)
- J I Malone
- Department of Pediatrics, College of Medicine, University of South Florida, Tampa 33612
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Clemens PC, Plettner C, Vellguth B. A simple procedure to exclude false-positive galactose screening test results caused by antibiotics. Clin Chim Acta 1990; 192:85-7. [PMID: 2261701 DOI: 10.1016/0009-8981(90)90275-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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Abstract
Rats fed a high galactose (30% galactose) diet (w/w) or made diabetic by injecting streptozotocin developed mature cataracts in approximately 45 and 90 days, respectively. Addition of allopurinol, a commonly used drug in the therapy of gout, to the high galactose diet or to the normal diet fed to diabetic rats advanced cataractogenesis in both the groups by approximately 50%. Allopurinol fed to control rats did not cause cataract formation. Feeding butylated hydroxy toluene (BHT), an antioxidant, prevented the allopurinol-induced advancement of cataract formation in galactosemic and diabetic rats. Assuming that these results are applicable in human subjects, there is need for caution in using allopurinol for the therapy of gout in diabetic subjects.
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Affiliation(s)
- N H Ansari
- Department of Human Biological Chemistry & Genetics, University of Texas Medical Branch, Galveston 77550
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19
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Abstract
Cataract, the major cause of blindness world-wide, may be caused partly by modification of lens proteins by carbamylation and non-enzymic glycosylation (glycation) in some patients. Aspirin has been found to protect against these modifications and to prevent cyanate-induced opacification occurring in whole rate lenses. Ibuprofen is an aspirin-like anti-inflammatory drug which appeared as a protective factor against cataract in an Oxford case-control study. The binding of cyanate, galactose and glucose 6-phosphate to lens proteins, and the effect of ibuprofen on this reaction was investigated, as was cyanate-induced opacification in whole rat lenses. Labelled metabolite was incubated with bovine lens homogenate in the presence and absence of ibuprofen, and the incorporation of label into the lens homogenate was followed. Simultaneous and preincubation experiments were performed. Intact rat lenses were incubated in culture medium with and without cyanate and ibuprofen. The phase separation temperature was noted as the temperature at which opacity first appeared on cooling. Cyanate, galactose and glucose 6-phosphate bind progressively to lens proteins. Simultaneous incubation with ibuprofen reduces cyanate and galactose binding but not glucose 6-phosphate. Ibuprofen protects against opacities due to cyanate-induced phase separation. Ibuprofen has protected against cataract in the models of cataractogenesis in this study. It appears to have a different mechanism of action from that of aspirin. These studies provide some support for the idea, based on epidemiological findings, that ibuprofen might be a useful anti-cataract drug.
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Affiliation(s)
- K A Roberts
- Nuffield Laboratory of Ophthalmology, University of Oxford, U.K
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20
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Abstract
Our recent investigations have shown that the Eisai compound, E-0722, (2R-4S-6-fluoro-1-2-methylspirochroman 4,4'-imidazolidine 2,5'-dione) is a more potent aldose reductase inhibitor than Sorbinil (D-6-fluorospirochroman 4,4'-imidazolidine 2,5'-dione). In the previous studies these aldose reductase inhibitors were added to the 50% galactose diet fed to rats to determine their effect on galactose-induced alterations in the lens and the development of cataract. In this report we present our results on the effect of prefeeding the aldose reductase inhibitor, E-0722, on the alterations in rat lens following subsequent feeding of galactose. For this study, young Sprague Dawley rats were prefed either rat chow or rat chow plus 50% galactose containing 1mg/day/Kg body weight of E-0722 for 1 or 2 weeks. After this dietary regimen, the animals were transferred to diets containing 50% galactose for different periods. For controls, rats were fed either rat chow or 50% galactose without the prefeeding of E-0722. Our results obtained through gross observation of the lenses, light microscopic studies of lens sections and assay of Na+-K+-ATPase (NPPase) activity show that the prefeeding of E-0722 prior to galactose feeding delays galactose-induced alterations and the development of mature cataract.
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Affiliation(s)
- N J Unakar
- Department of Biological Sciences, Oakland University, Rochester, MI 48309-4401
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21
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Cammarata PR, Jackson T, Yorio T. Sorbinil prevents the galactose-induced inhibition of prostaglandin synthesis in lens cells. Invest Ophthalmol Vis Sci 1988; 29:1452-60. [PMID: 3138202] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
The relationship between microsomal prostaglandin biosynthesis, PGH synthase activity and cell morphology was investigated with cultured bovine lens epithelial cells under physiological and hypergalactosemic conditions. The rate of lens cell microsomal PGE2 generation fell from 5.3 to 2.2 pg micrograms protein-1 min-1; PGF2 alpha declined from 7.7 to 4.8 pg micrograms protein-1 min-1 within 20 hr of exposure to 40 mM galactose. The decreased PGE2 and PGF2 alpha biosynthetic capability was attributed to a reduction in PGH synthase activity which reduced to 62% of control (5.5 mM glucose) after a 20 hr exposure to galactose. Measurement of PGH synthase activity after 6 days of continuous exposure to galactose resulted in a further reduction to 55% of control. The diminution in microsomal prostagladin biosynthesis and decline in PGH synthase activity precluded ultrastructural alterations, such as large vacuole formation and severe autodegradation of organelles. The simultaneous introduction of sorbinil, an aldose reductase inhibitor, to the galactose medium not only prevented the decrease in microsomal prostaglandin biosynthesis and PGH synthase activity, but also the detrimental morphological complications. The lens epithelial cell system may provide a useful model for examining the biochemical and morphological-related consequences of sustained hypergalactosemia and their potential regulation by aldose reductase inhibitors.
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Affiliation(s)
- P R Cammarata
- Department of Anatomy, Texas College of Osteopathic Medicine, Fort Worth 76107
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Vinardell MP, Bendahan G. Effect of age-dependent changes on jejunal and ileal amino acid-sugar interaction in vivo. Comp Biochem Physiol A Comp Physiol 1984; 78:363-6. [PMID: 6146450 DOI: 10.1016/0300-9629(84)90161-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
The effects of L-leucine on jejunal and ileal D-galactose absorption have been studied at three different ages in rats using a perfusion system in vivo. Both, D-galactose and L-leucine have been perfused through the jejunum and the ileum at two concentrations, 5mM (low) and 20 mM (high). L-leucine induced a reversible inhibition of D-galactose absorption at the three ages studied and in both intestinal segments. The inhibition was higher at 20 mM when carriers were saturated. A lineal correlation exits between the inhibition percentage and the age of animals, increasing with growth in the jejunum and decreasing in the ileum. Attention is called to the possibility of different transport mechanisms at low concentration (5 mM), one of low affinity in the jejunum and the other of high affinity in the ileum.
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Abstract
Lens ultrastructure and Na- K-ATPase activity in the lenses of rats fed galactose and a galactose + sorbinil diet (aldose reductase inhibitor) were studied. Lenses of rats on the galactose diet exhibited development of peripheral opacity within 3-4 days. This opacity progressed with the continuation of the galactose feeding, and by 20 days mature cataracts were observed in these animals. The formation of vacuoles, cysts, membrane disruption in the epithelium and fibers, and swelling of fibers accompanied the development of opacity. With the progression of opacity there was a considerable drop in lens Na- K-ATPase activity in the galactose-fed animals. However, the lenses of rats that were treated with sorbinil did not show any of the alterations in the ultrastructure of the epithelium and fibers that accompany galactose cataractogenesis. The level of Na-K-ATPase activity in the sorbinil-treated animals was similar to that found in lenses from the laboratory chow-fed group of rats. These observations further substantiate the role of aldose reductase in sugar-cataract development.
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Abstract
D-Galactonate dehydratase (D-galactonate hydro-lyase, EC 4.2.1.6) catalyzes the first reaction in the D-galactonate catabolic pathway of non-pathogenic Mycobacteria. As a part of studies concerning the metabolism of D-galactose and related compounds as well as its regulation in saprophytic strains of Mycobacteria, D-galactonate dehydratase has been purified and enzymologically characterized. The enzyme has been purified 325-fold from the crude extracts of galactose-grown Mycobacterium butyricum and its molecular weight of about 270,000 has been determined by Sephadex G-200 filtration. Isolation and analysis procedures are described. The dehydratase reaction is optimal within a pH range of 7.8 - 8.0. The enzyme is strictly specific for D-galactonate; none of the other sugar acids tested serves as a substrate or inhibits the dehydration of D-galactonate. The Km value for D-galactonate is 1 mM. The enzyme requires Mg2+ or Mn2+ for activity. The dehydratase is very sensitive to SH-blockers; the most potent inhibitor is ZnSO4, which considerably inhibits the enzyme at a concentration of 2.5 - 5.0 muM. Zinc-inhibited enzyme can be reactivated by chelating agents. The dehydratase is heat-resistant but dithiothreitol renders it more sensitive on heating.
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Abstract
The effect of ethanol (5--25 mM) on the galactose elimination kinetics in the intact liver was studied in the isolated perfused pig liver, using the steady-state infusion technique. Ethanol reduced galactose-Vmax on average to 0.07 mmol/min kg liver in six experiments from 0.43 mmol/min kg obtained in control experiments without ethanol. Also Km was significantly reduced from 0.23 mmol/l plasma water to 0.03 mmol/l. Ethanol increased UDP-galactose ten-fold simultaneous with a rise in hepatic outflow ratio of lactate to pyruvate to about 300 from 10; this indicates that ethanol inhibits epimerase. In experiments with increasing galactose elimination rates, the concentration of galactose-1-P increased much less than the concentration of galactose, and the phosphorylation of galactose therefore seems to be rate-limiting. In vitro galactokinase is inhibited by galactose-1-P. In the present study ethanol increased galactose-1-P five to ten times, and the reduction of Vmax and Km by ethanol could be explained by uncompetitive inhibition by galactose-1-P with Ki about 0.1 mmol/l. Ethanol decreased UDP-glucose to about 40% and UTP to less than 5%, probably due to trapping as UDP-galactose. This may depress the forward transferase reaction, and therefore the other co-substrate galactose-1-P rises--and inhibits galactokinase.
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Abstract
The enterotoxin of Shigella dysenteriae I produces fluid and electrolyte secretion in the rabbit ileum. These present studies were designed to evaluate nonelectrolyte transport in rabbit ileal mucosa exposed to Shigella enterotoxin. Both 10 mM galactose and 5 mM L-alanine absorptions were significantly impaired in enterotoxin-exposed ileal mucosa compared with control mucosa. L-Alanine influx was not imparied in two other secretory processes: that induced by cholera enterotoxin and hyperosmolarity. These studies provide evidence that both surgar and amino acid absorptions are diminished in the small intestine by the enterotoxin of S. dysenteriae I.
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Lichtenstein B, Winne D. The influence of blood flow on the phlorizine-insensitive and sensitive galactose absorption in rat jejunum. Naunyn Schmiedebergs Arch Pharmacol 1974; 282:195-212. [PMID: 4277704 DOI: 10.1007/bf00499034] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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Abstract
1. Analysis of transport of d-galactose was complicated by metabolism of the compound but appeared to have two components: a substrate-saturable component and a diffusion component. At low substrate concentration (<1mm) active transport was observed. Accumulation of galactose was largely independent of Na(+) concentration. The apparent K(m) for this component was 0.2mm. At substrate concentrations above 1mm the active transport system appeared saturated and further increases in substrate concentration resulted in a linear increase in the rate of galactose accumulation, but no concentration gradient was formed. 2. d-[1-(14)C]Galactose (2mm) was metabolized to (14)CO(2) by rat kidney-cortex slices incubated at 37 degrees C, at the rate of 68nmol/h per 100mg of tissue. 3. Intracellular components from such incubations were separated into a neutral fraction, the only major labelled component being galactose, and a phosphorylated fraction. 4. Phosphorylated metabolites found in galactose-incubated slices increased with increasing substrate concentration and achieved a limiting value of 0.42mm after 60min of incubation. 5. Galactose uptake was inhibited by anaerobiosis, dinitrophenol and phlorrhizin. 6. Methyl alpha-d-glucoside and d-glucose partially inhibited galactose uptake only at ratios of 100:1. 7. The presence of pyruvate did not decrease galactose metabolism although it did decrease production of (14)CO(2) from [1-(14)C]galactose. Gluconeogenesis occurred in the presence of pyruvate and (14)C from galactose was found in glucose. 8. Rat kidney-cortex slices metabolized 2mm-[1-(14)C]galactonate to (14)CO(2) at a rate of 20nmol/h per 100mg of tissue.
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Barnett JE, Ralph A, Munday KA. Structural requirements for active intestinal transport. The nature of the carrier-sugar bonding at C-2 and the ring oxygen of the sugar. Biochem J 1970; 118:843-50. [PMID: 5476727 PMCID: PMC1179295 DOI: 10.1042/bj1180843] [Citation(s) in RCA: 30] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Several weakly transported sugars were tested for transport by the Na(+)-dependent sugar carrier with slices of everted hamster intestinal tissue. Sugars were assumed to be transported by this carrier if the accumulation was diminished in the absence of Na(+) and in the presence of the competitive inhibitor 1,5-anhydro-d-glucitol. The extent of accumulation was correlated with the number of hydroxyl groups in the d-gluco configuration if the ring oxygen was placed in the normal d-glucose position. 5-Thio-d-glucose, with a sulphur atom in the ring, was transported at about the same rate as d-glucose and had a similar K(i) for d-galactose transport, but myoinositol was poorly accumulated. It is suggested that there is no hydrogen bonding at the ring oxygen atom, but that the oxygen atom is found at this position as a result of steric constraints. No sugar without a hydroxyl group in the d-gluco position at C-2 of the sugar, including d-mannose, 2-deoxy-d-glucose, 2-chloro-2-deoxy-d-glucose and 2-deoxy-2-fluoro-d-glucose, was transported by the Na(+)-dependent carrier, but these sugars and l-fucose weakly and competitively inhibit the Na(+)-dependent accumulation of l-glucose into slices of everted hamster intestinal tissue. It is concluded that the bond between the carrier and C-2 of the sugar may be covalent, and a possible mechanism for active intestinal transport is proposed.
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Charnecki A, Allen MJ. Cellular electrophysiology. XV. Effects of methyl-beta-D-thiogalactopyranoside and phenethyl alcohol on induced and repressed beta-galactosidase systems. Curr Mod Biol 1968; 1:325-8. [PMID: 4871031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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