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Wurster U, Hoffmann K. Two-month follow-up of the changes in vitreal constituents after argon laser coagulation of the retina in rabbits. Dev Ophthalmol 2015; 3:160-70. [PMID: 7197637 DOI: 10.1159/000396954] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
The response of the vitreous after panretinal argon laser photocoagulation was followed over a period of 60 days. Two phases can be discerned. An an immediate reaction to the disturbance of the blood-retinal barrier at the site of the pigment epithelium the total protein content and malate dehydrogenase activity rise sharply within 3 days, 4- to 5-fold above a normal. The more protracted increase of lysosomal enzyme activities which reach their peak heigh after 14 days only, can be attributed to the action and proliferation of phagocytic cells. 2 months after treatment all parameters have returned to their normal levels.
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Hoffmann K, Wurster U. Effect of experimental laser irradiation of the retina on the composition of the vitreous. Dev Ophthalmol 2015; 3:146-59. [PMID: 7197636 DOI: 10.1159/000396953] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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Ferreira GK, Carvalho-Silva M, Gomes LM, Scaini G, Teixeira LJ, Mota IT, Schuck PF, Ferreira GC, Streck EL. The characterization of neuroenergetic effects of chronic L-tyrosine administration in young rats: evidence for striatal susceptibility. Metab Brain Dis 2015; 30:215-21. [PMID: 25252880 DOI: 10.1007/s11011-014-9615-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [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: 03/18/2014] [Accepted: 09/03/2014] [Indexed: 10/24/2022]
Abstract
Tyrosinemia type II is an inborn error of metabolism caused by a deficiency in hepatic cytosolic aminotransferase. Affected patients usually present a variable degree of mental retardation, which may be related to the level of plasma tyrosine. In the present study we evaluated effect of chronic administration of L-tyrosine on the activities of citrate synthase, malate dehydrogenase, succinate dehydrogenase and complexes I, II, II-III and IV in cerebral cortex, hippocampus and striatum of rats in development. Chronic administration consisted of L-tyrosine (500 mg/kg) or saline injections 12 h apart for 24 days in Wistar rats (7 days old); rats were killed 12 h after last injection. Our results demonstrated that L-tyrosine inhibited the activity of citrate synthase in the hippocampus and striatum, malate dehydrogenase activity was increased in striatum and succinate dehydrogenase, complexes I and II-III activities were inhibited in striatum. However, complex IV activity was increased in hippocampus and inhibited in striatum. By these findings, we suggest that repeated administrations of L-tyrosine cause alterations in energy metabolism, which may be similar to the acute administration in brain of infant rats. Taking together the present findings and evidence from the literature, we hypothesize that energy metabolism impairment could be considered an important pathophysiological mechanism underlying the brain damage observed in patients with tyrosinemia type II.
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Affiliation(s)
- Gabriela K Ferreira
- Laboratório de Bioenergética, Programa de Pós-graduação em Ciências da Saúde, Universidade do Extremo Sul Catarinense, Criciúma, SC, Brazil
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Guo Q, Huang H, Pi Y, Zhang H. Evaluation of tear malate dehydrogenase 2 in mild dry eye disease. Eye Sci 2014; 29:204-208. [PMID: 26016071] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
PURPOSE To evaluate the effect of tear malate dehydrogenase 2 on monitoring ocular surface injury in mild dry eye (DE) disease. METHODS A total of 15 DE patients (30 eyes) with mild subjective symptoms but no ocular surface fluorescein staining signs were enrolled in this study (DE group). The control group was 15 healthy age- and sex-matched volunteers (30 eyes). All subjects were asked to fill out a DE symptoms questionnaire and take different tests including tear MDH and MDH2 activities evaluation, tear breakup time (TBUT), Schirmer I, and slit-lamp examination of the ocular surface. We investigated different changes in tear MDH and MDH2 activities in the DE group and control group, discussed the association between tear MDH2 activity and DE symptoms, and the relationship between tear MDH2 activity and diagnostic tests (Schirmer I and TBUT). We also analyzed the changes in tear MDH2 activities after the treatment with artificial tears. RESULTS Tear MDH activities in the DE group and control group were 288 ± 102 U/L and 259 ± 112 U/L, respectively, and this difference was not statistically significant (P > 0.05). The tear MDH2 activities in DE group were significantly increased compared with control group. Tear MDH2 was significantly and negatively correlated with the Schirmer's value (r = -0.733, P < 0.01) and the TBUT value (r = -0.841, P < 0.01). MDH2 also had a significant positive correlation with soreness symptoms (r = 0.687, P < 0.01). Treatment with artificial tears relieved or eliminated all discomfort symptoms, together with a considerable decrease in MDH2 activities (P < 0.01), but no significant changes in the Schirmer and the TBUT tests were observed. CONCLUSION Tear MDH2 activity can indicate ocular surface injury in mild DE patients and may be used to monitor the response to therapy.
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Gotoh N, Nagao K, Onoda S, Shirouchi B, Furuya K, Nagai T, Mizobe H, Ichioka K, Watanabe H, Yanagita T, Wada S. Effects of three different highly purified n-3 series highly unsaturated fatty acids on lipid metabolism in C57BL/KsJ-db/db mice. J Agric Food Chem 2009; 57:11047-11054. [PMID: 19848389 DOI: 10.1021/jf9026553] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Triglycerides (TG) consisting of highly purified (>97%) n-3 series highly unsaturated fatty acids, eicosapentaenoic acid (EPA), docosapentaenoic acid (DPA), and docosahexaenoic acid (DHA), were administered to C57BL/KsJ-db/db mice for 4 weeks by pair-feeding to compare their effects on lipid metabolism and to evaluate the effects of DPA on lipid metabolism. The hepatic TG level and total amount was decreased by treatment with DHA and DPA compared to the control. The efficacy of DPA was greater than that of EPA, but less than that of DHA. In contrast, EPA had the greatest serum TG reducing effect. The hepatic cytosol fraction of the DHA-treated group contained the lowest fatty acid synthase (FAS) and malic enzyme (ME) activity levels. Furthermore, the DHA-treated group contained the highest serum adiponectin concentrations. These findings indicate that the strong hepatic TG-lowering effect of DHA is due to the suppression of TG synthesis. The same tendencies were observed in DPA-treated mice, and the effect was stronger than that observed in EPA-treated mice, but equivalent to that observed in DHA-treated mice. Based on these results, DPA possesses lipid metabolism-improving effects. The beneficial effects of DPA for lipid metabolism were not superior to those of EPA and DHA, and the effect was always intermediate between those of EPA and DHA.
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Affiliation(s)
- Naohiro Gotoh
- Department of Food Science and Technology, Tokyo University of Marine Science and Technology, 4-5-7 Konan, Minato-ku, Tokyo 108-8477, Japan
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Reddy SS, Ramatholisamma P, Ramesh B, Baskar R, Saralakumari D. Beneficiary effect of Tinospora cordifolia against high-fructose diet induced abnormalities in carbohydrate and lipid metabolism in Wistar rats. Horm Metab Res 2009; 41:741-6. [PMID: 19764107 DOI: 10.1055/s-0029-1220922] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [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] [Indexed: 10/20/2022]
Abstract
High intake of dietary fructose has been shown to exert a number of adverse metabolic eff ects in humans and experimental animals. The present study was designed to investigate the eff ect of the aqueous extract of Tinospora cordifolia stem (TCAE) on the adverse eff ects of fructose loading toward carbohydrate and lipid metabolism in rats. Adult male Wistar rats of body weight around 200 g were divided into four groups, two of which were fed with starch diet and the other two with high fructose (66 %) diet. Plant extract of TC (400 mg/kg/day) was administered orally to each group of the starch fed rats and the highfructose fed rats. At the end of 60 days of experimental period, biochemical parameters related to carbohydrate and lipid metabolism were assayed. Hyperglycemia, hyperinsulinemia, hypertriglyceridemia, insulin resistance, and elevated levels of hepatic total lipids, cholesterol, triglycerides, and free fatty acids (p < 0.05) observed in fructose-fed rats were completely prevented with TCAE treatment. Alterations in the activities of enzymes of glucose metabolism (hexokinase, phosphofructokinase, pyruvate kinase, glucose-6-phosphatase, fructose-1,6-bisphosphatase, and glucose-6-phosphate dehydrogenase) and lipid metabolism (fatty acid synthetase, lipoprotein lipase, and malic enzyme) as observed in the high fructose-fed rats were prevented with TCAE administration. In conclusion, our fi ndings indicate improvement of glucose and lipid metabolism in high-fructose fed rats by treatment with Tinospora cordifolia, and suggest that the plant can be used as an adjuvant for the prevention and/or management of insulin resistance and disorders related to it.
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Affiliation(s)
- S Sreenivasa Reddy
- Department of Biochemistry, Sri Krishnadevaraya University, Anantapur, Andhra Pradesh, India
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Morín M, Monteoliva L, Insenser M, Gil C, Domínguez A. Proteomic analysis reveals metabolic changes during yeast to hypha transition in Yarrowia lipolytica. J Mass Spectrom 2007; 42:1453-1462. [PMID: 17960580 DOI: 10.1002/jms.1284] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Fungal dimorphism is important for survival in different environments and has been related to virulence. The ascomycete Yarrowia lipolytica can grow as yeast, pseudomycelial or mycelial forms. We have used a Y. lipolytica parental strain and a Deltahoy1 mutant, which is unable to form hypha, to set up a model for dimorphism and to characterize in more depth the yeast to hypha transition by proteomic techniques. A two-dimensional gel electrophoresis (2-DE) based differential expression analysis of Y. lipolytica yeast and hyphal cells was performed, and 45 differentially expressed proteins were detected; nine with decreased expression in hyphal cells were identified. They corresponded to the S. cerevisiae homologues of Imd4p, Pdx3p, Cdc19, Sse1p, Sol3p, Sod2p, Xpt1p, Mdh1p and to the unknown protein YALIOB00924g. Remarkably, most of these proteins are involved in metabolic pathways, with four showing oxidoreductase activity. Furthermore, taking into account that this is the first report of 2-DE analysis of Y. lipolytica protein extracts, 35 more proteins from the 2D map of soluble yeast proteins, which were involved in metabolism, cell rescue, energy and protein synthesis, were identified.
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Affiliation(s)
- Matías Morín
- Departamento de Microbiología y Genética, Instituto de Microbiología Bioquímica, CSIC/Universidad de Salamanca, 37007 Salamanca, Spain
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Shu B, Shen Y, Wang AM, Fang XQ, Li X, Deng HY, Yu ZQ. Histological, enzymohistochemical and biomechanical observation of skeletal muscle injury in rabbits. Chin J Traumatol 2007; 10:150-3. [PMID: 17535637] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
OBJECTIVE To explore the pathophysiological and biomechanical features of skeletal muscular injury for providing a rational basis for its treatment, prevention and rehabilitation. METHODS In 70 adult rabbits, the left tibialis anterior (TA) muscle was stretched to injury, while the right TA muscle served as control. Histological, enzymohistochemical and biomechanical changes were observed on days 0, 1, 2, 3, and 7 after injury. Cytochrome oxidase (CCO), acid phosphatase (ACP), ATPase, succinate dehydrogenase (SDH), malate dehydrogenase (MDH), NADH-diaphorase (NADHD), glutamatedehydrogenase (GDH), alpha-glycerophosphate dehydrogenase (alpha-GPD) and lactate dehydrogenase (LDH) were measured. The examined biomechanical parameters included maximal contractile force, ultimate load, length, energy absorption, tangent stiffness, and rupture site. RESULTS Partial or complete rupture of TA muscle occurred near the muscle-tendon junction. There was an intense inflammatory reaction on day 1 and 2 after injury. Endomysium fibrosis and myotube formation were observed on day 3, and developed further on day 7. The activity of cell oxidases (CCO, ATPase, MDH, alpha-GPD, SDH, NADHD and GDH) showed a significant drop from day 0 to 2, and resumed with different levels on day 3. The increment of enzymatic activities continued on day 7 and the levels of NADHD and alpha-GPD reached to the levels of control muscle. Maximal contractile force was 70.17%+/-3.82% of controls immediately after injury, 54.82%+/-3.09% at 1 day, 66.41%+/-4.36% at 2 days, 78.39%+/-4.90% at 3 days and 93.64%+/-5.02% at 7 days. Ultimate load was 85.78%+/-7.54% of controls at the moment of injury, 61.44%+/-5.91% at 1 day, 49.17%+/-4.26% at 2 days, 64.43%+/-5.02% at 3 days, and 76.71%+/-6.46% at 7 days. CONCLUSIONS Endomysium fibrosis and scar formation at the injured site are responsible for frequent recurrence of skeletal muscle injury. Recovery of tensile load slower than that of maximal contractile force may be another cause. Whether the injured muscle returns to normal exercise is mainly determined by the tensility on which the muscle-tendon can bear rather than the maximal contractile force.
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Affiliation(s)
- Bin Shu
- Department of Rehabilitation Medicine, Research Institute of Surgery, Daping Hospital, Third Military Medical University, Chongqing 400042, China.
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Yang J, Shen J. Relayed (13)C magnetization transfer: detection of malate dehydrogenase reaction in vivo. J Magn Reson 2007; 184:344-9. [PMID: 17126047 PMCID: PMC2800356 DOI: 10.1016/j.jmr.2006.11.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2006] [Revised: 11/03/2006] [Accepted: 11/03/2006] [Indexed: 05/12/2023]
Abstract
Malate dehydrogenase catalyzes rapid interconversion between dilute metabolites oxaloacetate and malate. Both oxaloacetate and malate are below the detection threshold of in vivo MRS. Oxaloacetate is also in rapid exchange with aspartate catalyzed by aspartate aminotransferase, the latter metabolite is observable in vivo using (13)C MRS. We hypothesized that the rapid turnover of oxaloacetate can effectively relay perturbation of magnetization between malate and aspartate. Here, we report indirect observation of the malate dehydrogenase reaction by saturating malate C2 resonance at 71.2 ppm and detecting a reduced aspartate C2 signal at 53.2 ppm due to relayed magnetization transfer via oxaloacetate C2 at 201.3 ppm. Using this strategy the rate of the cerebral malate dehydrogenase reaction was determined to be 9+/-2 micromol/g wet weight/min (means+/-SD, n=5) at 11.7 Tesla in anesthetized adult rats infused with [1,6-(13)C(2)]glucose.
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Affiliation(s)
- Jehoon Yang
- Molecular Imaging Branch, National Institute of Mental Health Intramural Research Program, National Institutes of Health, 9000 Rockville Pike, Bethesda, MD 20892-1527, USA
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Leroux A, Fleming-Canepa X, Aranda A, Maugeri D, Cazzulo JJ, Sánchez MA, Nowicki C. Functional characterization and subcellular localization of the three malate dehydrogenase isozymes in Leishmania spp. Mol Biochem Parasitol 2006; 149:74-85. [PMID: 16750864 DOI: 10.1016/j.molbiopara.2006.04.010] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2005] [Revised: 04/25/2006] [Accepted: 04/27/2006] [Indexed: 11/19/2022]
Abstract
As part of a study on the malate dehydrogenase isozymes (MDHs) from Trypanosomatids, three different fractions with MDH activity were obtained from crude extracts of Leishmania mexicana promastigotes combining two different chromatographic steps. Gel filtration chromatography in native conditions showed that most of the MDH activity present in the crude extracts eluted in a single peak, which corresponded to a lower apparent molecular mass ( congruent with 57kDa) than the value expected for typical MDHs. To further characterize the leishmanial isozymes, three putative MDH genes, presumably corresponding to the mitochondrial, glycosomal and cytosolic isoforms were amplified by PCR, cloned into bacterial expression vectors, and the recombinant enzymes purified. Digitonin extraction of intact L. mexicana promastigotes and immunofluorescence microscopy of L. major promastigotes confirmed the subcellular compartmentation of each of the three isozymes. Western blot analysis showed that the three MDHs are developmentally regulated. At the protein level, these isozymes are remarkably more abundant in amastigotes than in promastigotes of L. mexicana. Altogether our results demonstrate the presence of three MDH isoforms with slightly distinct biochemical properties and different subcellular localization in Leishmania spp. Presumably the functional and biochemical features of these isozymes reflect the metabolic adaptation to the different nutrient sources these parasites have to face along their life cycle. These results also emphasize the differences among Trypanosomatids in this area of metabolism, since in the case of Trypanosoma brucei the cMDH is the only isoform expressed in bloodstream trypomastigotes, whereas in Trypanosoma cruzi cMDH is absent.
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Affiliation(s)
- Alejandro Leroux
- Instituto de Química y Fisicoquímica Biológica IQUIFIB-CONICET, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Junín 956, CP1113 Buenos Aires, Argentina
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VOZNESENSKAYA ELENAV, FRANCESCHI VINCENTR, CHUONG SIMONDX, EDWARDS GERALDE. Functional characterization of phosphoenolpyruvate carboxykinase-type C4 leaf anatomy: immuno-, cytochemical and ultrastructural analyses. Ann Bot 2006; 98:77-91. [PMID: 16704997 PMCID: PMC2803547 DOI: 10.1093/aob/mcl096] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2005] [Revised: 02/15/2006] [Accepted: 03/22/2006] [Indexed: 05/09/2023]
Abstract
BACKGROUND AND AIMS Species having C4 photosynthesis belonging to the phosphoenolpyruvate carboxykinase (PEP-CK) subtype, which are found only in family Poaceae, have the most complex biochemistry among the three C4 subtypes. In this study, biochemical (western blots and immunolocalization of some key photosynthetic enzymes) and structural analyses were made on several species to further understand the PEP-CK system. This included PEP-CK-type C4 species Urochloa texana (subfamily Panicoideae), Spartina alterniflora and S. anglica (subfamily Chloridoideae), and an NADP-ME-type C4 species, Echinochloa frumentacea, which has substantial levels of PEP-CK. KEY RESULTS Urochloa texana has typical Kranz anatomy with granal chloroplasts scattered around the cytoplasm in bundle sheath (BS) cells, while the Spartina spp. have BS forming long adaxial extensions above the vascular tissue and with chloroplasts in a strictly centrifugal position. Despite some structural and size differences, in all three PEP-CK species the chloroplasts in mesophyll and BS cells have a similar granal index (% appressed thylakoids). Immunolocalization studies show PEP-CK (which catalyses ATP-dependent decarboxylation) is located in the cytosol, and NAD-ME in the mitochondria, in BS cells, and in the BS extensions of Spartina. In the NADP-ME species E. frumentacea, PEP-CK is also located in the cytosol of BS cells, NAD-ME is very low, and the source of ATP to support PEP-CK is not established. CONCLUSIONS Representative PEP-CK species from two subfamilies of polyphyletic origin have very similar biochemistry, compartmentation and chloroplast grana structure. Based on the results with PEP-CK species, schemes are presented with mesophyll and BS chloroplasts providing equivalent reductive power which show bioenergetics of carbon assimilation involving C4 cycles (PEP-CK and NAD-ME, the latter functioning to generate ATP to support the PEP-CK reaction), and the consequences of any photorespiration.
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Affiliation(s)
- ELENA V. VOZNESENSKAYA
- Laboratory of Anatomy and Morphology, V. L. Komarov Botanical Institute of Russian Academy of Sciences, Prof. Popov Street 2, 197376, St. Petersburg, Russia and School of Biological Sciences, Washington State University, Pullman, WA 99164-4236, USA
| | - VINCENT R. FRANCESCHI
- Laboratory of Anatomy and Morphology, V. L. Komarov Botanical Institute of Russian Academy of Sciences, Prof. Popov Street 2, 197376, St. Petersburg, Russia and School of Biological Sciences, Washington State University, Pullman, WA 99164-4236, USA
| | - SIMON D. X. CHUONG
- Laboratory of Anatomy and Morphology, V. L. Komarov Botanical Institute of Russian Academy of Sciences, Prof. Popov Street 2, 197376, St. Petersburg, Russia and School of Biological Sciences, Washington State University, Pullman, WA 99164-4236, USA
| | - GERALD E. EDWARDS
- Laboratory of Anatomy and Morphology, V. L. Komarov Botanical Institute of Russian Academy of Sciences, Prof. Popov Street 2, 197376, St. Petersburg, Russia and School of Biological Sciences, Washington State University, Pullman, WA 99164-4236, USA
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Luo C, Wang X, Long J, Liu J. An NADH-tetrazolium-coupled sensitive assay for malate dehydrogenase in mitochondria and crude tissue homogenates. ACTA ACUST UNITED AC 2006; 68:101-11. [PMID: 16740313 DOI: 10.1016/j.jbbm.2006.04.003] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2006] [Revised: 04/14/2006] [Accepted: 04/18/2006] [Indexed: 11/28/2022]
Abstract
A sensitive spectrophotometric assay for determining mitochondrial malate dehydrogenase activity is described. The assay measures NADH production by coupling it to the reduction of 2-(p-iodophenyl)-3(p-nitrophenyl)-5-phenyl tetrazolium chloride (INT). Via an intermediate electron carrier, either phenazine methosulfate or lipoamide dehydrogenase, INT accepts electrons and is reduced to a red-colored formazan, which can be quantified by spectrophotometer at 500 nm. This assay uses only commercial reagents but gives a 2-5 fold (with lipoamide dehydrogenase) or 5-20 fold (with phenazine methosulfate) activity increase over currently available assays for pure enzyme in mitochondria isolated from human neuroblastoma cells, rat brain and liver, and crude homogenates of rat brain and liver. The assay can be easily performed with 96-well plate and less than 2.5 microg protein of isolated mitochondria or crude tissue homogenate. These results suggest that this assay is a simple, sensitive, stable and inexpensive method with wide application.
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Affiliation(s)
- Cheng Luo
- Institute for Nutritional Science, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, 200031, PR China
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Abstract
AIM The incidence of coronary heart diseases (CHD), congestive heart failure (CHF) and myocardial infarction is higher in diabetic patients than in non-diabetic groups, with these incidences being more in women than in the men. Hence, we examined involvement of mitochondrial energy transduction functions. METHODS Mitochondrial energy metabolism in cardiomyopathy was studied using streptozotocin (STZ)-diabetic male and female rats as the model system. Effects of insulin treatment were also evaluated. RESULTS The body and heart weights decreased in both male and female diabetic rats. Insulin treatments resulted in significant increase in the body and heart weights in the female rats. Mitochondrial respiration rates with all the substrates tested decreased in diabetic condition in both males and females. Treatment with two dose-regimens of insulin had differential restorative effect on mitochondrial substrate oxidation in the males but caused hyper-stimulation in the females. Diabetic state brought about 19% decrease in the cytochrome aa(3) content in the female rats. Treatment with 0.6 units of insulin significantly increased the cytochrome contents in general in both the sexes whereas higher dose (1.0 unit) caused decrease in the cytochromes content in the females. Diabetic state resulted in decreased dehydrogenases activities; insulin treatments had differential effect on the dehydrogenase activity in the males and the females. The results suggest that insulin treatment-induced hyper-stimulation of respiration in female rats may lead to increased production of reactive oxygen species. Besides, increased formation of advanced glycosylated end products may further lead to increased risk of CHF and CHD. CONCLUSIONS The results suggest that differential effects of STZ-diabetes and insulin treatments in the female rats than in males may be the underlying cause for increased incidence of diabetic cardiomyopathies in the females.
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Aranda A, Maugeri D, Uttaro AD, Opperdoes F, Cazzulo JJ, Nowicki C. The malate dehydrogenase isoforms from Trypanosoma brucei: subcellular localization and differential expression in bloodstream and procyclic forms. Int J Parasitol 2005; 36:295-307. [PMID: 16321390 DOI: 10.1016/j.ijpara.2005.09.013] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2005] [Revised: 09/14/2005] [Accepted: 09/16/2005] [Indexed: 11/24/2022]
Abstract
Trypanosoma brucei procyclic forms possess three different malate dehydrogenase isozymes that could be separated by hydrophobic interaction chromatography and were recognized as the mitochondrial, glycosomal and cytosolic malate dehydrogenase isozymes. The latter is the only malate dehydrogenase expressed in the bloodstream forms, thus confirming that the expression of malate dehydrogenase isozymes is regulated during the T. brucei life cycle. To achieve further biochemical characterization, the genes encoding mitochondrial and glycosomal malate dehydrogenase were cloned on the basis of previously reported nucleotide sequences and the recombinant enzymes were functionally expressed in Escherichia coli cultures. Mitochondrial malate dehydrogenase showed to be more active than glycosomal malate dehydrogenase in the reduction of oxaloacetate; nearly 80% of the total activity in procyclic crude extracts corresponds to the former isozyme which also catalyzes, although less efficiently, the reduction of p-hydroxyphenyl-pyruvate. The rabbit antisera raised against each of the recombinant isozymes showed that the three malate dehydrogenases do not cross-react immunologically. Immunofluorescence experiments using these antisera confirmed the glycosomal and mitochondrial localization of glycosomal and mitochondrial malate dehydrogenase, as well as a cytosolic localization for the third malate dehydrogenase isozyme. These results clearly distinguish Trypanosoma brucei from Trypanosoma cruzi, since in the latter parasite a cytosolic malate dehydrogenase is not present and mitochondrial malate dehydrogenase specifically reduces oxaloacetate.
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Affiliation(s)
- Alejandro Aranda
- Instituto de Química y Fisicoquímica Biológica IQUIFIB-CONICET, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Junín 956, CP1113, Argentina
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Tomita T, Fushinobu S, Kuzuyama T, Nishiyama M. Crystal structure of NAD-dependent malate dehydrogenase complexed with NADP(H). Biochem Biophys Res Commun 2005; 334:613-8. [PMID: 16009341 DOI: 10.1016/j.bbrc.2005.06.133] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2005] [Accepted: 06/23/2005] [Indexed: 11/29/2022]
Abstract
For better understanding of the coenzyme specificity in NAD-dependent MDH (tMDH) from Thermus flavus AT-62, we determined the crystal structures of tMDH-NADP(H) complex at maximally 1.65 A resolution. The overall structure is almost the same as that of the tMDH-NADH complex. However, NADP(H) binds to tMDH in the reverse orientation, where adenine occupies the position near the catalytic center and nicotinamide is positioned at the adenine binding site of the tMDH-NADH complex. Consistent with this, kinetic analysis of the malate-oxidizing reaction revealed that NADP(+) inhibited tMDH at high concentrations. This has provided the first evidence for the alternative binding mode of the nicotinamide coenzyme, that has pseudo-symmetry in its structure, in a single enzyme.
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Affiliation(s)
- Takeo Tomita
- Biotechnology Research Center, The University of Tokyo, Bunkyo-ku, Tokyo 113-8657, Japan
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Klaus S, Pültz S, Thöne-Reineke C, Wolfram S. Epigallocatechin gallate attenuates diet-induced obesity in mice by decreasing energy absorption and increasing fat oxidation. Int J Obes (Lond) 2005; 29:615-23. [PMID: 15738931 DOI: 10.1038/sj.ijo.0802926] [Citation(s) in RCA: 289] [Impact Index Per Article: 15.2] [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] [Indexed: 11/09/2022]
Abstract
OBJECTIVE To examine the antiobesity effect of epigallocatechin gallate (EGCG), a green tea bioactive polyphenol in a mouse model of diet-induced obesity. METHODS Obesity was induced in male New Zealand black mice by feeding of a high-fat diet. EGCG purified from green tea (TEAVIGO) was supplemented in the diet (0.5 and 1%). Body composition (quantitative magnetic resonance), food intake, and food digestibility were recorded over a 4-week period. Animals were killed and mRNA levels of uncoupling proteins (UCP1-3), leptin, malic enzyme (ME), stearoyl-CoA desaturase-1 (SCD1), glucokinase (GK), and pyruvate kinase (PK) were analysed in different tissues. Also investigated were acute effects of orally administered EGCG (500 mg/kg) on body temperature, activity (transponders), and energy expenditure (indirect calorimetry). RESULTS Dietary supplementation of EGCG resulted in a dose-dependent attenuation of body fat accumulation. Food intake was not affected but faeces energy content was slightly increased by EGCG, indicating a reduced food digestibility and thus reduced long-term energy absorption. Leptin and SCD1 gene expression in white fat was reduced but SCD1 and UCP1 expression in brown fat was not changed. In liver, gene expression of SCD1, ME, and GK was reduced and that of UCP2 increased. Acute oral administration of EGCG over 3 days had no effect on body temperature, activity, and energy expenditure, whereas respiratory quotient during night (activity phase) was decreased, supportive of a decreased lipogenesis and increased fat oxidation. CONCLUSIONS Dietary EGCG attenuated diet-induced body fat accretion in mice. EGCG apparently promoted fat oxidation, but its fat-reducing effect could be entirely explained by its effect in reducing diet digestibility.
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Affiliation(s)
- S Klaus
- Group of Energy Metabolism, German Institute of Human Nutrition in Potsdam, Nuthetal, Germany.
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18
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Schlieker C, Tews I, Bukau B, Mogk A. Solubilization of aggregated proteins by ClpB/DnaK relies on the continuous extraction of unfolded polypeptides. FEBS Lett 2005; 578:351-6. [PMID: 15589844 DOI: 10.1016/j.febslet.2004.11.051] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2004] [Revised: 11/04/2004] [Accepted: 11/17/2004] [Indexed: 11/24/2022]
Abstract
The AAA+ chaperone ClpB solubilizes in cooperation with the DnaK chaperone system aggregated proteins. The mechanistic features of the protein disaggregation process are poorly understood. Here, we investigated the mechanism of ClpB/DnaK-dependent solubilization of heat-aggregated malate dehydrogenase (MDH) by following characteristics of MDH aggregates during the disaggregation reaction. We demonstrate that disaggregation is achieved by the continuous extraction of unfolded MDH molecules and not by fragmentation of large MDH aggregates. These findings support a ClpB-dependent threading mechanism as an integral part of the disaggregation reaction.
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Affiliation(s)
- Christian Schlieker
- ZMBH, Universität Heidelberg, Im Neuenheimer Feld 282, Heidelberg D-69120, Germany
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Gaye-Siessegger J, Focken U, Abel HJ, Becker K. Improving estimates of trophic shift in Nile tilapia, Oreochromis niloticus (L.), using measurements of lipogenic enzyme activities in the liver. Comp Biochem Physiol A Mol Integr Physiol 2005; 140:117-24. [PMID: 15664320 DOI: 10.1016/j.cbpb.2004.11.011] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2004] [Revised: 11/12/2004] [Accepted: 11/14/2004] [Indexed: 10/26/2022]
Abstract
To test whether the measurement of selected enzyme activities could be used to estimate more precisely the trophic shift of C isotopes, Nile tilapia (Oreochromis niloticus) were fed semi-synthetic diets differing in their lipid contents (1.7%, 5.0%, 10.8% and 20.0%). The diets were formulated to contain the same amount of nitrogen and metabolizable energy and were made from casein, wheat starch, corn germ oil supplemented with vitamins, minerals and L-arginine. The influence of the different diets on the activity of two lipogenic enzymes, ATP-citrate lyase and malic enzyme, on delta13C values in the whole fish, the liver and their correlation was investigated. There was a strong positive correlation between delta13C values in the lipids of whole fish and those of their livers. The activities of lipogenic enzymes increased significantly with increasing trophic shift of C isotopes (Deltadelta13Cdiet-fish values) in the lipids. If the relationship between trophic shift and enzyme activity can be confirmed in situations where feed quantity and quality are not known, the determination of enzyme activities would enable better estimates of the trophic shift to be made thus significantly improving back-calculation of diets from stable isotope data.
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Affiliation(s)
- J Gaye-Siessegger
- Department of Aquaculture Systems and Animal Nutrition in the Tropics and Subtropics, University of Hohenheim (480b), Fruwirthstr. 12, 70599 Stuttgart, Germany
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20
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Hurníková Z, Snábel V, Pozio E, Reiterová K, Hrcková G, Halásová D, Dubinský P. First record of Trichinella pseudospiralis in the Slovak Republic found in domestic focus. Vet Parasitol 2004; 128:91-8. [PMID: 15725537 DOI: 10.1016/j.vetpar.2004.11.013] [Citation(s) in RCA: 29] [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] [Received: 05/18/2004] [Revised: 10/12/2004] [Accepted: 11/02/2004] [Indexed: 11/25/2022]
Abstract
Infection of Trichinella spp. is widespread among wildlife in Slovakia and the red fox (Vulpes vulpes) is the main reservoir of Trichinella britovi. Trichinella spiralis has been rarely documented in sylvatic and domestic animals of this country. During routine examination of domestic pigs at the slaughter, Trichinella larvae were detected by artificial digestion in a domestic pig of a large-scale breeding farm in Eastern Slovakia. The parasite has been identified by molecular (PCR) and biochemical (allozymes) analyses and by the morphology of the nurse cell as the non-encapsulated species Trichinella pseudospiralis infecting both mammals and birds. The epidemiological investigation carried out at the farm level revealed the presence of the same parasite species in other three pigs of 192 examined (2.1%), in 3 of 14 (21.4%) examined synanthropic rats (Rattus norvegicus) and in a domestic cat. The farm was characterized by inadequate sanitary conditions, insufficient nutrition, cannibalism and the presence of rat population. A different profile has been observed at the phosphoglucomutase locus in T. pseudospiralis isolates from Slovakia in comparison with the T. pseudospiralis reference isolate from the Palearctic region. This is the first documented focus of T. pseudospiralis from Central Europe. The detection in domestic pigs of a non-encapsulated parasite infecting both mammals and birds stresses the need to avoid the use of trichinelloscopy to detect this infection at the slaughterhouse.
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Affiliation(s)
- Z Hurníková
- Parasitological Institute of Slovak Academy of Sciences, Hlinkova 3, 040 01 Kosice, Slovak Republic.
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21
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Shimazaki Y, Sugawara Y, Ohtsuka Y, Manabe T. Analysis of the activity and identification of enzymes after separation of cytosol proteins in mouse liver by microscale nondenaturing two-dimensional electrophoresis. Proteomics 2004; 3:2002-7. [PMID: 14625862 DOI: 10.1002/pmic.200300467] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.6] [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: 11/09/2022]
Abstract
Enzyme activities such as of fructose bisphosphatase, malate dehydrogenase and carbonic anhydrase were analyzed after cytosol proteins in the mouse liver and were separated using nondenaturing two-dimensional electrophoresis (2-DE). The activities of both fructose bisphosphatase and malate dehydrogenase were inhibited by thyroxine, and fructose bisphosphatase activity was specifically inhibited by adenosine monophosphate in nondenaturing 2-DE. Furthermore, polypeptides of the separated proteins were analyzed by peptide mass fingerprinting using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry or by peptide sequencing using electrospray ionization-tandem mass spectrometry, or both. Proteins separated by 2-DE were identified. These results indicate that the function of proteins such as enzyme activity, and their sequence structure can be analyzed, for example by peptide mapping and peptide sequencing, after the proteins have been separated by nondenaturing 2-DE. Present results also indicate analysis of enzyme activity using nondenaturing 2-DE can be applied to screen substances which affect enzyme activity.
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Affiliation(s)
- Youji Shimazaki
- Department of Physics and Chemistry, Faculty of Science and Venture Business Laboratory, Ehime University, Matsuyama, Japan.
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22
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Shimazaki Y, Sugawara Y, Manabe T. Nondenaturing two-dimensional electrophoresis enzyme profile involving activity and sequence structure of cytosol proteins from mouse liver. Proteomics 2004; 4:1406-11. [PMID: 15188408 DOI: 10.1002/pmic.200300702] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [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: 11/10/2022]
Abstract
After cytosol proteins in the mouse liver were separated by nondenaturing two-dimensional electrophoresis (2-DE), activities of several enzymes, such as fructose bisphosphatase, sorbitol dehydrogenase and malate dehydrogenase, transferase and sorbitol dehydrogenase, or several dehydrogenases, were analyzed on the same 2-D gel. Further, peptidase (or protease) activity can be examined by matrix-assisted laser desorption/ionization-time of flight-mass spectrometry (MALDI-TOF-MS) when peptides such as angiotensin and adenocorticotropic hormone are incubated in the presence of the cytosol protein separated by nondenaturing 2-DE. Sequence structures of proteins on the 2-D gel were analyzed by peptide mass fingerprinting using MALDI-TOF-MS or by peptide sequencing using electrospray ionization-tandem mass spectrometry (ESI-MS/MS). The combination of activity and sequence structure accurately verified the position and activity range of the separated enzymes on the nondenaturing 2-D gel. From these results, we created a nondenaturing 2-D enzyme profile involving activities and sequence structure of cytosol proteins from mouse liver. This profile can be used for checking whether activities of enzymes were specifically or nonspecifically inhibited by inhibitors.
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Affiliation(s)
- Youji Shimazaki
- Department of Physics and Chemistry, Faculti of Science and Venture Business Laboratory, Ehime University, Matsuyama, Japan.
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Miñana-Galbis D, Farfán M, Fusté MC, Lorén JG. Genetic diversity and population structure of Aeromonas hydrophila, Aer. bestiarum, Aer. salmonicida and Aer. popoffii by multilocus enzyme electrophoresis (MLEE). Environ Microbiol 2004; 6:198-208. [PMID: 14871204 DOI: 10.1046/j.1462-2920.2004.00554.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [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
Genetic diversity, genetic relationship, identification and population structure of 120 Aeromonas strains (including Aer. hydrophila, Aer. bestiarum, Aer. salmonicida and Aer. popoffii) isolated from various sources were studied by analysis of 15 genetic loci by multilocus enzyme electrophoresis (MLEE). All 15 loci were polymorphic, with an average of 9.4 alleles per locus and a mean genetic diversity (H) of 0.64. Cluster analysis defined at H < or = 0.7 differentiated most of the taxa analysed except the Aer. popoffii and Aer. bestiarum strains, which showed a close genetic relationship. Allelic frequencies of five loci (EST1, HEX, IDH, LDH1 and MDH) identified 94% of the strains. The index of association (IA) for the total sample was 2.38 and IA values calculated for the different populations were always significantly different from zero. These results suggest that the population structure of this Aeromonas sample is strongly clonal, confirm the taxonomic status of the analysed species in population genetics terms, and show the usefulness of MLEE for identifying Aeromonas species.
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Affiliation(s)
- David Miñana-Galbis
- Departament de Microbiologia i Parasitologia Sanitàries, Facultat de Farmàcia, Divisió IV, Universitat de Barcelona, Avinguda. Joan XXIII s/n, 08028 Barcelona, Spain
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Nadol'nik LI, Netsetskaia ZV, Vinogradov VV. [Effect of long-term exposure to low dose gamma-irradiation on the rat thyroid status]. Radiats Biol Radioecol 2004; 44:76-80. [PMID: 15060946] [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: 04/29/2023]
Abstract
The effect of long-term exposure to low-dose external radiation on the rat thyroid status was studied. The experiments were carried out on Wistar female rats. The single doses absorbed were 0.1; 0.25; 0.5 Gy. The rats were irradiated 20 times (5 days x 4 weeks). The animals were decapitated after 1, 30 and 180 days following the last irradiation. Blood serum was assayed for content of thyroxin (T4) and triiodothyronine (T3) radioimmunologically. The liver was spectrophotometrically assayed for thyroid-induced NADP-malatedehydrogenase (NADP-MDH). It was shown that the long-term 0.5-Gy irradiation of the animals induced a decrease in blood T4 and T3 concentrations 1.34-1.71-fold and 1.24-1.43-fold after 1, 30 and 180 days, respectively. The T3 level was diminished most pronouncedly after 1 day, whereas that of T4--after 30 days following the exposure. With the doses of 0.1 and 0.25 Gy absorbed, the T4 and T3 concentration remained unchanged throughout all the periods studied. The activity of NADP-MDH was decreased 1.55-2.46-fold in all the experimental animals, and it was held decreased after 180 days (1.43-1.50-fold) in 0.25- and 0.5-Gy-irradiated groups, which indicates a disturbance in thyroid hormone metabolism in rats exposed chronically to low-dose radiation. After 180 days, the experimental animals experienced an elevation of thyroid gland weight on 15-20%. The thyroid status disturbance seemed to be due to both inhibited T4 and T3 biosynthesis in thyroid and disturbed hormone peripheral metabolism under radiation exposure.
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Affiliation(s)
- L I Nadol'nik
- Institute of Biochemistry, National Academy of Sciences of Belarus, Grodno, 230017 Belarus
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25
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Cetica P, Pintos L, Dalvit G, Beconi M. Involvement of enzymes of amino acid metabolism and tricarboxylic acid cycle in bovine oocyte maturation in vitro. Reproduction 2003; 126:753-63. [PMID: 14748694] [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: 04/28/2023]
Abstract
Few studies demonstrate at a biochemical level the metabolic profile of both cumulus cells and the oocyte during maturation. The aim of the present study was to investigate the differential participation of enzymatic activity in cumulus cells and in the oocyte during in vitro maturation (IVM) by studying the activity of enzymes involved in the control of amino acid metabolism, alanine aminotransferase (ALT) and aspartate aminotransferase (AST); and the tricarboxylic acid (TCA) cycle, isocitrate dehydrogenase (IDH) and malate dehydrogenase (MDH). No NAD-dependent isocitrate dehydrogenase (NAD-IDH) activity was recorded in cumulus-oocyte complexes (COCs). ALT, AST, NADP-dependent isocitrate dehydrogenase (NADP-IDH) and MDH enzymatic units remained constant in cumulus cells and oocytes during IVM. Specific activities increased in oocytes and decreased in cumulus cells as a result of IVM (P<0.05). Similar activity of both transaminases was detected in cumulus cells, unlike in the oocyte, in which activity of AST was 4.4 times greater than that of ALT (P<0.05). High NADP-IDH and MDH activity was detected in the oocyte. Addition of alanine, aspartate, isocitrate + NADP, oxaloacetate or malate + NAD to maturation media increased the percentage of denuded oocytes reaching maturation (P<0.05), in contrast to COCs in which differences were not observed by addition of these substrates and co-enzymes. The activity of studied enzymes and the use of oxidative substrates denotes a major participation of transaminations and the TCA cycle in the process of gamete maturation. The oocyte thus seems versatile in the use of several oxidative substrates depending on the redox state.
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Affiliation(s)
- P Cetica
- Area of Biochemistry, School of Veterinary Sciences, University of Buenos Aires, Chorroarín 280, (C1427CWO) Buenos Aires, Argentina
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26
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Abstract
Forty-two dikaryotic and 42 monokaryotic isolates, and 34 pairings were examined by horizontal polyacrylamide gel electrophoresis (PAGE) for six enzymatic activities, viz. EST, 6PGD, IDH, MDH, SHDH and SOD. 44 bands were analysed. Numerical analysis of the isoenzymatic patterns was undertaken and compared with those from morphological characters. The analysis of six enzymatic systems showed the existence of four monomorphic systems (IDH, MDH, SHDH and SOD). The sterease system (EST) appears to be polymorphic in Polyporus ciliatus and in populations of P. tenuiculus from Argentina, being monomorphic in the remaining species studied. The 6PGD system is polymorphic in P. tucumanensis and monomorphic in the other species. Predominance of monomorphic enzymes and a clear distribution of the electromorphs among the species, indicates that isoenzymatic analysis is a good taxonomic tool within Polyporus. The low intraspecific variability allowed the use of interspecific differences to separate species. Numerical analysis showed a good correlation between morphological and molecular characters. In the isoenzymatic phenogram the similarity index is high only among very close species, showing a stressed separation of species.
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Affiliation(s)
- Rosa M Borges da Silveira
- Departamento de Botânica, Instituto de Biociências, Universidade Federal do Rio Grande do Sul, 90046-900 Porto Alegre, RGS, Brazil.
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Abstract
Seven-day-old chickens were fed diets containing 18% crude protein + 0 or 1g methimazole/kg to produce either euthyroid or hypothyroid groups of birds at 28 days of age. These two groups were then offered diets containing either 0 or 1mg triiodothyronine (T(3))/kg diet. Birds were sampled at 0, 2, 5, and 8 days following the onset of the T(3) treatment. Measurements taken at these intervals included in vitro hepatic lipogenesis (IVL), growth and feed consumption, hepatic enzyme activities (malic enzyme, ME; isocitrate dehydrogenase, ICD; and aspartate amino transferase, AAT), plasma hormones (T(3); thyroxine, T(4); insulin like growth factors I, IGF-I; and insulin like growth factors II, IGF-II) and metabolites (glucose; fatty acids, NEFA; triglyerides; uric acid). Hypothyroidism decreased IVL and ME at 28 days of age; however, T(3) supplementation for 2 days restored both IVL and ME. Paradoxically, continuing T(3) replenishment for an additional 3-6 days decreased IVL without affecting ME activity. In contrast, supplemental T(3) decreased IVL in euthyroid birds, regardless of the dosing interval, but had no effect on ME activity. Methimazole decreased plasma T(3), T(4), uric acid, and IGF-I, but did not affect IGF-II at 28 days. Giving T(3) to birds previously on methimazole increased plasma IGF-I as did feeding a control diet. Supplemental T(3) increased NEFA in both euthyroid and hypothyroid birds, but only for a short period following the initiation of supplementation (2 days post-supplementation). These data may help to explain some of the apparent reported dichotomies in lipid metabolism elicited by changes in the thyroid state of animals. In addition, most metabolic changes in response to feeding T(3) occurred within 2-5 days, suggesting that changes in intermediary metabolism preceded morphological changes. In conclusion, the thyroid state of the animal will determine responses to exogenous T(3).
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Affiliation(s)
- R W Rosebrough
- Growth Biology Laboratory, Animal and Natural Resources Institute, United States Department of Agriculture-Agricultural Research Service, Beltsville Agricultural Research Center, Beltsville, MD 20705, USA.
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Nadol'nik LI, Netsetskaia ZV, Vinogradov VV. [Effects of single-dose external gamma irradiation on rat thyroid status as observed during the year]. Radiats Biol Radioecol 2003; 43:65-70. [PMID: 12677661] [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: 03/01/2023]
Abstract
We studied the rat thyroid status depending on the dose of external radiation and the time passed after the exposure. The experiments were carried out on female albino Wistar rats. The doses absorbed amounted to 0.25; 0.5; 1.0; 2.0 and 5.0 Gy. The animals were decapitated after 3, 6, 24 hours and 7, 30, 180 and 365 days following the radiation. The blood serum was assayed for the contents of thyroxin (T4) and triiodothyronine (T3) using a radioimmunological technique. The liver tissue was assayed spectrophotometrically for the activity of thyroid-induced NADP malate dehydrogenase (NADP-MDH). No changes were found in the blood thyroid hormone contents within short periods after the radiation effect. After 6 hours the T4 levels was 1.2-1.3-fold decreased in the blood of rats receiving the radiation doses of 1.0; 2.0; and 5.0 Gy. After a day the T4 concentration was diminished by 1.21-193-fold in all the experimental animals independently of the radiation dose and that of T3--in 2.0 Gy--and 5.0 Gy--irradiated group. After 7 days following the radiation the T4 and T3 contents remained to be decreased by 1.37-1.75 fold and those of NADP-MDH--by 1.3-1.8-fold in all the animal groups. In a month, the low dose-treated animals (0.25, 0.5, 1.0 Gy) showed the level of thyroid hormones reduced to the control values, whereas the 2.0 and 5.0 Gy--treated rats demonstrated this reduction only by 6 months. The decreased concentration of blood thyroid hormones was due not to the activation of their peripheral metabolism, but, probably, to inhibition of their biosynthesis in thyroid cells under conditions of radiation-induced activation of oxidative stress.
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Affiliation(s)
- L I Nadol'nik
- Institute of Biochemistry, National Academy of Sciences of Belarus, Grodno, 230017 Belarus
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Rungi AA, Primeau A, Nunes Christie L, Gordon JW, Robinson BH, Hood DA. Events upstream of mitochondrial protein import limit the oxidative capacity of fibroblasts in multiple mitochondrial disease. Biochim Biophys Acta 2002; 1586:146-54. [PMID: 11959456 DOI: 10.1016/s0925-4439(01)00072-2] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
To investigate whether protein import is defective in mitochondrial disease, we compared the rate of import and the expression of protein import machinery components in skin fibroblasts from control subjects and a patient with multiple mitochondrial disease (MMD). The patient exhibited a 35% decrease in cytochrome c oxidase activity and a 59% decrease in cellular oxygen consumption compared to control. Western blot analyses revealed that patient levels of MDH, mtHSP70, HSP60, and Tom20 protein were 57%, 20%, 75% and 100% of control cells, respectively. MDH and Tom20 mRNA levels were not different from control levels, whereas mtHSP70 mRNA were 50% greater than control. Radiolabeled MDH was imported into mitochondria with equal efficiency between patient (44% of total synthesized) and control (43%) cells, although the total MDH synthesized in patient cells was reduced by about 40%. The unaffected levels of mRNA and post-translational import into mitochondria, combined with reduced protein levels of MDH, mtHSP70, and HSP60 suggest a translational defect in this patient with MMD. This was verified by the 50% reduction in overall cellular protein synthesis in the patient compared to control. Further, the similar import rates between patient and control cells suggest an important role for Tom20, but a lesser role for mtHSP70 in regulating protein import into mitochondria.
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Affiliation(s)
- Arne A Rungi
- Department of Kinesiology, Toronto, ON, Canada M3J 1P3
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30
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Sudeep AB, Shouche YS, Mourya DT, Pant U. New Helicoverpa armigera Hbn cell line from larval hemocyte for baculovirus studies. Indian J Exp Biol 2002; 40:69-73. [PMID: 12561972] [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: 02/28/2023]
Abstract
A new cell line from the larval hemocytes of H. armigera was established in Grace's medium modified by adding lactalbumin hydrolysate and yeastolate (3.3g/l), and supplemented with fetal bovine serum (20%). The cell line was designated as NIV-HA-1195. The cell population at P-78 consisted mainly of epithelial-like cells (89.36%), fibroblast-like cells (8.31%) and giant cells (2.13%). The population doubling time was 96hr at P-8, 60hr at P-43. The chromosome number ranged from 45 to 200. The cell line is susceptible to the baculoviruses, Autographa californica nucleopolyhedrovirus (AcNPV), Spodoptera litura NPV and the homologous HaNPV. Isoenzyme profile and results of 16S rRNA heteroduplex analysis clearly indicated the species specificity of the new cell line.
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Affiliation(s)
- A B Sudeep
- National Institute of Virology, 20-A, Dr. Ambedkar Road, Pune 411 001, India
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31
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Affiliation(s)
- R Bazin
- Institut Biomédical des Cordeliers, INSERM U-465, Paris, France
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Grindley PB, Omoruyi FO, Asemota HN, Morrison EY. Effect of yam (Dioscorea cayenensis) and dasheen (Colocassia esculenta) extracts on the kidney of streptozotocin-induced diabetic rats. Int J Food Sci Nutr 2001; 52:429-33. [PMID: 11517735 DOI: 10.1080/09637480120078311] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [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: 10/17/2022]
Abstract
Streptozotocin-induced diabetic wistar rats were maintained for 4 weeks on a supplement of extracts of yam (Dioscorea cayenensis) or dasheen (Colocassia esculenta). The activities of malic enzyme, NADP+ isocitrate dehydrogenase, Glucose 6-P-dehydrogenase and the transaminases were determined to assess any degree of metabolic alteration caused by diabetic nephropathy. Diabetic rats fed normal diet and those fed yam extract, dasheen extract and commercial linamarin respectively lost weight significantly compared to healthy controls. The diabetic rats fed dasheen extract, maintained near normoglycaemic values compared to diabetic rats on normal diet (P < 0.05). Malic enzyme activity was significantly reduced (P < 0.05) in diabetic rats on the normal diet compared to normal healthy controls. Feeding of yam or dasheen extract raised the activity of this enzyme towards normal. Feeding of dasheen extract or commercial linamarin significantly lowered (P < 0.05) the activity of NADP+ isocitrate dehydrogenase below that of healthy controls. Glucose 6-P-dehydrogenase activity was significantly increased (P < 0.05) in diabetic rats compared to healthy controls. Alanine transaminase in the kidney of diabetic rats fed yam extract was significantly higher than healthy controls (P < 0.05). These results demonstrate an overall aggravation of the diabetic nephropathy by yam and dasheen extracts in the diet. In the Caribbean region where these foods are dietary staples, there may be a correlation with the reported high prevalence of diabetes mellitus and the development of renal disease.
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Affiliation(s)
- P B Grindley
- Department of Basic Medical Sciences (Biochemistry Section) and Biotechnology Centre, University of the West Indies, Mona, Kingston 7, Jamaica
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Abstract
Ten isolates of Trypanosoma evansi from the Pantanal region of Brazil, recently derived from coati (Nasua nasua, carnivora, Procyonidae), horses and dogs, were characterized on the basis of biological (experimental infections in Wistar rats) and biochemical (multilocus enzyme eletrophoresis) data. Biological data were analyzed by Nested analysis of variance and Kruskal-Wallis. Marked heterogeneity in virulence was observed in the isolates. Some of the isolates showed an undulating parasitaemia, typical for African trypanosomes. This biological heterogeneity did not correspond with the biochemical homogeneity observed in the T. evansi isolates. T. evansi has one of the widest distributions and greatest range of mammalian hosts and is widely recognized to have evolved from Trypanosoma brucei. Adaptability of T. evansi was not reflected in the variability of biochemical and molecular parameters studied to date. The variability in virulence was very significant, but not correlated with the host from which it was derived. These data suggested that, in the region studied, T. evansi is transmitted among both domestic and sylvatic animals in one single transmission cycle.
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Affiliation(s)
- A O Queiroz
- Department of Protozoology, Instituto Oswaldo Cruz, Fiocruz, A.v. Brasil, 4365, CEP: 21045-900, Rio de Janeiro, Brazil
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34
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Chatterjee K, Dey M. Electrophoretic investigation on seven species of Indian frogs. Cytobios 2000; 94:25-30. [PMID: 9853367] [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: 02/09/2023]
Abstract
Studies on the occurrence of protein polymorphism are of importance not only in determining interspecific relationships but also in revealing genetically controlled variants among the populations of the same species. This study deals with the analysis of the isozyme pattern of three dehydrogenases in seven species of Indian frogs. The results correlate with the respective habitats and it is suggested that protein polymorphism is adaptively important and is maintained by natural selection.
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Affiliation(s)
- K Chatterjee
- Department of Zoology, School of Life Sciences, North-Eastern Hill University, Shillong, India
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35
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Gerfault V, Louveau I, Mourot J, Le Dividich J. Lipogenic enzyme activities in subcutaneous adipose tissue and skeletal muscle from neonatal pigs consuming maternal or formula milk. Reprod Nutr Dev 2000; 40:103-12. [PMID: 10863955 DOI: 10.1051/rnd:2000123] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
The influence of maternal and formula milk on lipid metabolism was studied in 7-day-old pigs. Lipid content, fatty acid composition, lipogenic enzyme activities and expression of GLUT4 mRNA were determined in subcutaneous adipose tissue and skeletal muscle from pigs that were bottle-fed formula milk (F) or sow milk (SM), or were sow-reared (SR). Bottle-fed pigs were isoenergetically fed and achieved similar daily body weight gain. SR pigs have a higher (P < 0.05) body weight gain than bottle-fed pigs. Lipid content of adipose tissue was lower (P < 0.05) in F than in SM and SR pigs. In muscle, lipid content did not differ significantly between groups. In adipose tissue, acetyl-CoA-carboxylase (CBX), fatty acid synthase (FAS), malic enzyme (ME), glucose-6-phosphate-dehydrogenase (G6PDH) and lipoprotein lipase (LPL) activities and GLUT4 mRNA levels were higher (P < 0.05) in SR than in bottle-fed pigs. In muscle, ME and G6PDH activities and GLUT4 mRNA were higher (P < 0.05) in F than in SM and SR pigs; LPL was not detected. The present study indicates that lipogenic enzyme activities and GLUT4 mRNA expression are regulated differently in subcutaneous adipose tissue and skeletal muscle in the neonatal pig.
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Affiliation(s)
- V Gerfault
- Unité Mixte de Recherches sur le Veau et le Porc, INRA, Saint-Gilles, France
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36
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Arias P, Cutillas C, Oliveros R, Guevara DC. Characterization of Chabertia ovina by isoenzyme gel electrophoresis: comparative study with Oesophagostomum venulosum. Parasitol Res 1999; 85:884-6. [PMID: 10540947 DOI: 10.1007/s004360050652] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [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: 10/28/2022]
Abstract
The glucose-6-phosphate dehydrogenase (G6PD, EC.1.1.1.49), glucose phosphate isomerase (GPI, EC.5.3.1.9), and malate dehydrogenase (MDH, EC.1.1.1.37) isoenzymatic patterns of Chabertia ovina were determined by starch-gel electrophoresis. The G6PD and GPI isoenzymatic patterns were characterized by the existence of three phenotypes: (1) a single and slow anodic band, (2) a single and fast anodic band, and (3) a large spot matching its migration with bands 1 and 2. These three phenotypes may be explained as the existence of only one gene locus for the G6PD and GPI in C. ovina. Allelic frequencies and the Hardy-Weinberg test were determined. This test indicated that the population was not in Hardy-Weinberg equilibrium. The MDH isoenzymatic pattern of C. ovina was characterized by the presence of two bands with anodic and cathodic migration. Furthermore, comparative isoenzyme studies were carried out between Oesophagostomum venulosum and C. ovina. The different G6PD, GPI, and MDH isoenzymatic patterns observed for the two species allowed us to distinguish them and, therefore, to use isoenzymatic patterns as a diagnostic tool to discriminate these species.
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Affiliation(s)
- P Arias
- Department of Microbiology and Parasitology, Faculty of Pharmacy, University of Sevilla, Spain
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37
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Louassini M, Foulquié M, Benítez R, Adroher J. Citric-acid cycle key enzyme activities during in vitro growth and metacyclogenesis of Leishmania infantum promastigotes. J Parasitol 1999; 85:595-602. [PMID: 10461937] [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: 02/13/2023] Open
Abstract
The activities of 5 key regulatory enzymes in most energetic systems, namely citrate synthase (EC 4.1.3.7, CS), NADP-specific isocitrate dehydrogenase (EC 1.1.1.42, ICDH), succinate dehydrogenase (EC 1.3.99.1, SDH), L-malate dehydrogenase (EC 1.1.1.37, MDH), and decarboxylating malic enzyme (EC 1.1.1.40, ME), were measured during the growth and metacyclogenesis of a cutaneous (CL) and a visceral (VL) strain of Leishmania infantum. As occurs with other Leishmania species, infective promastigotes were present along all phases of growth, but their percentages were higher at the early stationary phase for VL and the end of the same phase for CL. High CS and SDH activities were detected in both strains, as compared with other trypanosomatids, bringing more evidence for an actively functional citric-acid cycle in L. infantum. Both strains showed higher levels of CS, ICDH, and MDH and lower SDH and ME activities when more metacyclic promastigotes were present, but in VL these changes paralleled an increase in glucose consumption, whereas in CL these changes coincided with an NH3 hyperproduction. This suggests that the energy metabolism during L. infantum growth and metacyclogenesis is affected by regulated enzymes that probably respond to changes in the culture medium in the levels of glucose and amino acids.
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Affiliation(s)
- M Louassini
- Department of Parasitology, Faculty of Pharmacy, University of Granada, Spain
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38
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Ramirez-Gil H, Feldberg E, Almeida-Val VM, Val AL. Karyological, biochemical, and physiological aspects of Callophysus macropterus (Siluriformes, Pimelodidae) from the Solimões and Negro Rivers (central Amazon). Braz J Med Biol Res 1998; 31:1449-58. [PMID: 9921283 DOI: 10.1590/s0100-879x1998001100014] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [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: 11/21/2022] Open
Abstract
Karyological characteristics, i.e., diploid number, chromosome morphology and nucleolus organizer regions (NORs), biochemical characteristics, i.e., electrophoretic analysis of blood hemoglobin and the tissue enzymes lactate dehydrogenase (LDH), malate dehydrogenase (MDH), alcohol dehydrogenase (ADH), and phosphoglucose isomerase (PGI), and physiological characteristics, i.e., relative concentration of hemoglobin and intraerythrocytic concentrations of organic phosphates were analyzed for the species Callophysus macropterus collected from Marchantaria Island (white water system--Solimões River) and Anavilhanas Archipelago (black water system--Negro River). Karyological and biochemical data did not reveal significant differences between specimens collected at the two sites. However, the relative distribution of hemoglobin bands I and III (I = 16.33 +/- 1.05 and III = 37.20 +/- 1.32 for Marchantaria specimens and I = 6.33 +/- 1.32 and III = 48.05 +/- 1.55 for Anavilhanas specimens) and levels of intraerythrocytic GTP (1.32 +/- 0.16 and 2.76 +/- 0.18 for Marchantaria and Anavilhanas specimens, respectively), but not ATP or total phosphate, were significantly different, indicating a physiological adaptation to the environmental conditions of these habitats. It is suggested that C. macropterus specimens from the two collecting sites belong to a single population, and that they adjusted some physiological characteristics to adapt to local environmental conditions.
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Affiliation(s)
- H Ramirez-Gil
- Instituto Nacional de Pesca y Acuicultura, INPA, Puerto López, Meta, Colombia
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39
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Vogel R, Jennemann G, Seitz J, Wiesinger H, Hamprecht B. Mitochondrial malic enzyme: purification from bovine brain, generation of an antiserum, and immunocytochemical localization in neurons of rat brain. J Neurochem 1998; 71:844-52. [PMID: 9681477 DOI: 10.1046/j.1471-4159.1998.71020844.x] [Citation(s) in RCA: 40] [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
To elucidate the cellular location of mitochondrial malic enzyme in brain, immunocytochemical studies were performed. For this purpose, mitochondrial malic enzyme was purified to apparent homogeneity from bovine brain and used for the immunization of rabbits. Subjecting the antiserum to affinity purification on immobilized antigen as an absorbent yielded a purified immunoreactive antibody preparation, which was characterized by probing cytosolic and mitochondrial fractions of bovine and rat brain in western blotting. As neither cross-reactivity with cytosolic malic enzyme nor immunoreactivity against other proteins could be observed, the antibody preparation was found suitable for immunocytochemistry. By using sections of perfusion-fixed rat brain, considerable resolution was achieved at the light-microscopic level. Distinct and specific staining of neurons was observed; in contrast, no staining of astrocytes and possibly unspecific staining within the nuclei of oligodendrocytes were obtained. From these data, it is concluded that mitochondrial malic enzyme is located in neurons; however, in astrocytes, the enzyme appears to be either lacking or present at a much lower level. A protective role against oxidative stress in neurons is proposed for mitochondrial malic enzyme.
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Affiliation(s)
- R Vogel
- Physiologisch-chemisches Institut der Universität Tübingen, Germany
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40
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Vogel R, Hamprecht B, Wiesinger H. Malic enzyme isoforms in astrocytes: comparative study on activities in rat brain tissue and astroglia-rich primary cultures. Neurosci Lett 1998; 247:123-6. [PMID: 9655608 DOI: 10.1016/s0304-3940(98)00290-0] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.1] [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: 02/08/2023]
Abstract
Anion exchange chromatography on diethylaminoethyl cellulose was optimized to separate the cytosolic and mitochondrial isoforms of malic enzyme from rat brain. Extracts of adult rat brain and of astroglia-rich primary cultures derived from the brains of newborn rats were analyzed for their content of the two isozymes. In the case of brain tissue 45% of malic enzyme activity was due to the cytosolic isoform. In contrast, in extracts from astroglia-rich primary cultures more than 95% of the total activity was associated with the cytosolic isozyme. From these data it is concluded that the cytosolic rather than the mitochondrial isoform of malic enzyme has prominent functions in astroglial metabolism.
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Affiliation(s)
- R Vogel
- Physiologisch-chemisches Institut der Universität Tübingen, Germany
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41
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Anderson SA, Carter V, Parsons M. Trypanosoma brucei: molecular cloning and stage-regulated expression of a malate dehydrogenase localized to the mitochondrion. Exp Parasitol 1998; 89:63-70. [PMID: 9603490 DOI: 10.1006/expr.1998.4260] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [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: 11/22/2022]
Abstract
African trypanosomes exhibit dramatic developmental changes in carbohydrate and energy metabolism, with cytochrome-mediated respiration playing an important role only in the insect stages. The parasites possess three isozymes of malate dehydrogenase, each of which has a different subcellular localization and, likely, a distinct metabolic role. We have cloned and characterized a cDNA encoding one of these malate dehydrogenases. Epitope tagging and transfection experiments demonstrate that the corresponding protein is localized to the mitochondrion and that an intact amino terminus is required for proper compartmentalization. The abundance of transcript is developmentally regulated, with higher levels in procyclic stage parasites.
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Affiliation(s)
- S A Anderson
- Seattle Biomedical Research Institute, Washington 98109, USA
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42
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Abstract
Rats were exposed to gamma radiation from a 60Co source, receiving 0.25 Gy at weekly intervals. During 2 d before each irradiation, the animals received daily intragastric doses of 26 mg pantothenol or 15 mg beta-carotene per kg body weight. One hour after the third irradiation session, the animals were killed and their livers were analyzed. In animals not supplied with pantothenol, the irradiation resulted in a significant decrease of total liver lipids and a 50% decrease in phospholipids. Liver cholesterol was decreased by about 20%. Irradiation produced lipid peroxidation as expressed by doubling of the amounts of conjugated dienes and ketone dienes and of thiobarbituric acid reactive compounds. The amount of CoA in liver was decreased by 24% and that of reduced glutathione by 40%. The NAD+/NADH ratio was increased by 60% and the activity of NADP-dependent malate dehydrogenase (decarboxylating) was decreased by 26%. The amount of pantothenic acid and its derivatives (expressed as pantolactone-generating compounds) in blood decreased by about 80%. In rats to which pantothenol was administered, the content of pantothenic acid in blood was tripled compared to nonirradiated (control) rats, and all the biochemical parameters measured in liver were the same as in nonirradiated animals.
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Affiliation(s)
- V S Slyshenkov
- Institute of Biochemistry, Academy of Sciences of Belarus, Grodno
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43
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Abstract
Chitinolytic activities were identified in the Protozoa Trichomonas vaginalis. Overall chitinase activity assessed using chitine-azure as substrate was 10.93 +/- 1.21 nmoles/min/mg prot. End nonreducing chitobiosidase (exochitinase) and chitotriosidase (endochitinase) activities were shown using p-nitrophenyl-substrates and had specific activities of 4.55 +/- 0.53 and 0.47 +/- 0.06 nmol/min/mg prot, Kmapp. = 1.32 mM and 5 microM and pH optimum = 7.0 and 6.1 respectively. beta-N-acetylhexosaminidase (NAHase) activity was also detected with a specific activity of 5.40 +/- 0.65 nmol/min/mg prot., Kmapp = 0.656 mM and pH optimum at 7.0. No release of these enzymes into the culture medium was found. The possible role of chitinases in T. vaginalis remains to be investigated.
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Affiliation(s)
- A Sanon
- Biologie et Contrôle des Organismes Parasites, Faculté de Pharmacie, Université de Paris-Sud, Châtenay-Malabry
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44
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Könönen E, Mättö J, Väisänen-Tunkelrott ML, Frandsen EV, Helander I, Asikainen S, Finegold SM, Jousimies-Somer H. Biochemical and genetic characterization of a Prevotella intermedia/nigrescens-like organism. Int J Syst Bacteriol 1998; 48 Pt 1:39-46. [PMID: 9542074 DOI: 10.1099/00207713-48-1-39] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Thirty-three previously non-typable faintly pigmented Gram-negative anaerobic bacterial isolates, biochemically most closely related to Prevotella intermedia and Prevotella nigrescens, were analysed for enzymic reactions, cellular fatty acid (CFA) composition, electrophoretic mobility of malate and glutamate dehydrogenases, hybridization with P. intermedia and P. nigrescens species-specific oligonucleotide probes and, for genetic heterogeneity, by arbitrarily primed PCR (AP-PCR). P. intermedia ATCC 25611T and P. nigrescens ATCC 33563T were run in parallel for comparison. Twenty-nine isolates originated from the normal oral flora of 18 subjects (including five mother-child pairs), and four isolates from various infections. Except for a negative lipase reaction, enzymic profiles of the test isolates were similar to those of P. intermedia and P. nigrescens. Clustering of CFAs, electrophoretic mobility patterns, hybridization with DNA probes for P. intermedia and P. nigrescens, and AP-PCR band patterns of the test isolates differed from those of the type strains of P. intermedia and P. nigrescens, suggesting the existence, in humans, of a new anaerobic species of pigmented, moderately saccharolytic, indole-positive Gram-negative rods.
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Affiliation(s)
- E Könönen
- Anaerobe Reference Laboratory, National Public Health Institute, Helsinki, Finland
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45
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Witt U, Lührs R, Buck F, Lembke K, Grüneberg-Seiler M, Abel W. Mitochondrial malate dehydrogenases in Brassica napus: altered protein patterns in different nuclear mitochondrial combinations. Plant Mol Biol 1997; 35:1015-1021. [PMID: 9426623 DOI: 10.1023/a:1005969620157] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Two-dimensional analyses of mitochondrial proteins of Brassica napus revealed a set of differences in patterns of mitochondrial matrix proteins isolated from different nuclear backgrounds. One of these varying proteins was identified as mitochondrial malate dehydrogenase (mMDH;EC 1.1.1.37) by homology analyses of the partial amino acid sequence. Immunological detection identified additional mMDH subunits and detected different patterns of mMDH subunits in two distinct mitochondria types although they were isolated from plants with the same nuclear genotype. These differences are also reflected in isozym patterns, whereas Southern analyses showed no alteration in genome structure. Therefore mitochondria type-specific mMDH modifications are possible.
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Affiliation(s)
- U Witt
- Institut für Allgemeine Botanik, Universität Hamburg, Germany
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46
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Affiliation(s)
- A D Uttaro
- International Institute of Cellular and Molecular Pathology (ICP), Catholic University of Louvain, Brussels, Belgium
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47
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Rab MA, al Rustamani L, Bhutta RA, Mahmood MT, Evans DA. Cutaneous leishmaniasis: iso-enzyme characterisation of Leishmania tropica. J PAK MED ASSOC 1997; 47:270-3. [PMID: 9510629] [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: 02/06/2023]
Abstract
In order to identify and characterise the organisms responsible for Cutaneous Leishmaniasis, parasites were isolated from active lesions, grown in-vitro cultures and identified by iso-enzyme characterisation. Thirteen isolates from different patients were typed as L. tropica. Seven of these isolates were from Afghan refugees encamped in the suburbs of Islamabad, 3 were from patients in Multan, 1 was from a patient from Azad Jammu and Kashmir and 1 was from Besham (Swat, NWFP). The study confirms the presence of anthroponotic Cutaneous Leishamaniasis caused by L. Tropica in Pakistan.
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Affiliation(s)
- M A Rab
- Health Services Academy, Ministry of Health and National Institute of Health, Islamabad
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48
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Chou WY, Huang SM, Chang GG. Functional roles of the N-terminal amino acid residues in the Mn(II)-L-malate binding and subunit interactions of pigeon liver malic enzyme. Protein Eng 1997; 10:1205-11. [PMID: 9488145 DOI: 10.1093/protein/10.10.1205] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Pigeon liver malic enzyme has an N-terminal amino acid sequence of Met-Lys-Lys-Gly-Tyr-Glu-. In this work, various mutants of the enzyme with individual or combinational deletion (delta) or substitution at these amino acids were constructed and functionally expressed in Escherichia coli cells. A major protein band corresponding to an Mr of approximately 65000 was observed for all recombinant enzymes in sodium dodecyl sulfate polyacrylamide gel electrophoresis. However, when examining by polyacrylamide gel electrophoresis under native conditions, the recombinant enzymes were found to possess a tetrameric structure with Mr approximately 260000 or a mixture of tetramers and dimers with the exception of delta(K2K3G4) and delta(1-16) mutants, which existed exclusively as dimers at the protein concentration we employed. K3A and K3E also dissociated substantially. K(2,3)A was a tetramer but K(2,3)E essentially existed as dimers. All tetramers and dimers were enzymatically active in the gels. All mutants displayed a similar apparent Km value for NADP+. The apparent Km for L-malate and Mn(II), on the other hand, was increased by 4-27-fold for the delta(K2/K3) and the delta(1-16) mutants. The small binding affinity of delta(K2/K3) with Mn(II)-L-malate was specific. With additional deletion at positions 3 and/or 4, the delta(K2K3), delta(K2G4/K3G4) or delta(K2K3G4) mutants exhibited similar kinetic properties for the wild type. The lysine residues at the positions 2 or 3 seem to be crucial for the correct active site conformation. The results indicate that the N-terminus of malic enzyme is located at the Mn(II)-L-malate binding domain of the active center and is also near the subunit's interface. These results were interpreted with our asymmetric double-dimer model for the enzyme in which the N-terminus was involved in the head-to-tail monomer-monomer interactions but not the dimer-dimer interactions.
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Affiliation(s)
- W Y Chou
- Department of Biochemistry, National Defense Medical Center, Taipei, Taiwan
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49
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Abstract
The malate (MDH) and lactate (LDH) dehydrogenases belong to the homologous class of 2-ketoacid dehydrogenases. The specificity for their respective substrates depends on residues differing at two or three regions within each molecule. Theoretical peptide-mass fingerprinting and PROSITE analysis of nine MDH and six LDH molecules were used to describe conserved sites related to function. A unique LDH is described which probably also confers MDH activity within the 580 kbp genome of Mycoplasma genitalium (class: Mollicutes). A single hydrophilic arginine residue was found in the active site of the M. genitalium LDH enzyme, differing from an hydrophobic residue normally present in these molecules. The effect of this residue may be to alter active site substrate specificity, allowing the enzyme to perform two closely related tasks. Evidence for a single gene affording dual enzymatic function is discussed in terms of genome size reduction in the simplest of free-living organisms. Since Mollicutes are thought to lack enzymes of the tricarboxylic acid cycle that would otherwise bind and interact with MDH in bacterial species possessing this pathway, active site modification of M. genitalium LDH is the sole requirement for MDH activity of this molecule. The closely related helical Mollicute, Spiroplasma melliferum, was shown to possess two distinct gene products for MDH/LDH activity.
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Affiliation(s)
- S J Cordwell
- Centre for Proteome Research and Gene-Product Mapping, Australian Technology Park, Eveleigh
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50
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Li S, Zhou Q. [Analysis of malate dehydrogenase isozymes in Taihe negro fowl by thin-layer isoelectric focusing polyacrylamide gel electrophoresis]. Zhongguo Zhong Yao Za Zhi 1997; 22:325-6, 382. [PMID: 11038880] [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: 02/18/2023]
Abstract
The isozyme patterns of malate dehydrogenase (MDH) from six tissues (liver, kidney, eye, muscle, brain and heart) of the Taihe negro fowl (Gallus gallus domesticus Brission) were analysed by thin-layer isoelectric focusing polyacrylamide gel electrophoresis. It was found that there were twelve MDH isozyme bands in the tissues of the fowl, and these isozymes displayed a tissue-specific distribution.
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Affiliation(s)
- S Li
- Department of Biological Science and Technology, Nanchang University
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