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Silvia Ravera Isabella Panfoli Maria Grazia Aluigi Daniela Calzia Alessandro Morelli 《Cell biochemistry and biophysics》2011,59(2):63-70
FoF1-ATP synthase is the nanomotor responsible for most of ATP synthesis in the cell. In physiological conditions, it carries
out ATP synthesis thanks to a proton gradient generated by the respiratory chain in the inner mitochondrial membrane. We previously
reported that isolated myelin vesicles (IMV) contain functional FoF1-ATP synthase and respiratory chain complexes and are able to conduct an aerobic metabolism, to support the axonal energy
demand. In this study, by biochemical assay, Western Blot (WB) analysis and immunofluorescence microscopy, we characterized
the IMV FoF1-ATP synthase. ATP synthase activity decreased in the presence of the specific inhibitors (olygomicin, DCCD, FCCP, valynomicin/nigericin)
and respiratory chain inhibitors (antimycin A, KCN), suggesting a coupling of oxygen consumption and ATP synthesis. ATPase
activity was inhibited in low pH conditions. WB and microscopy analyses of both IMV and optic nerves showed that the Inhibitor
of F1 (IF1), a small protein that binds the F1 moiety in low pH when of oxygen supply is impaired, is expressed in myelin sheath. Data are discussed in terms of the role
of IF1 in the prevention of the reversal of ATP synthase in myelin sheath during central nervous system ischemic events. Overall,
data are consistent with an energetic role of myelin sheath, and may shed light on the relationship among demyelination and
axonal degeneration. 相似文献
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Early changes in morphology and polypeptide pattern of plastids from watermelon cotyledons induced by benzyladenine or light are very similar 总被引:1,自引:0,他引:1
Marcella Bracale Giovanna P. Longo Gianfranca Rossi Claudio P. Longo 《Physiologia plantarum》1988,72(1):94-100
Watermelon ( Citrullus vulgaris Schrad. cv. Fairfax) cotyledons were excised from the embryo and grown in the dark for 4 days. They were then transferred to 10 μm benzyladenine (BA) solution or illuminated with white light. We have compared changes in ultrastructure of the plastids and of their polypeptide pattern induced by the two treatments.
At the end of the 4-day-period in the dark the plastids differentiated to amyloplasts and had few polypeptides: only the two subunits of ribulose bisphosphate carboxylase (RuBP) were clearly observed. Both light and BA induced starch depletion and gratia formation after 12–24 h. BA was less efficient than light in inducing thylakoid formation and more efficient in inducing starch depletion. After 6 h both factors induced the appearance of the same new polypeptides in the 28–53 kDa range. Most prominent among them is a 32 kDa band. Light is much more effective in inducing the formation of a 29 kDa band than is BA. In mature chloroplasts this band stains very strongly, while the 32 kDa band disappears. We suggest that the 29 kDa polypeptide is the light harvesting complex (LHC), since a purified LHC preparation from cotyledons grown either on water in light or on BA in the dark migrates on the polyacrylamide gel as a single 29 kDa band. 相似文献
At the end of the 4-day-period in the dark the plastids differentiated to amyloplasts and had few polypeptides: only the two subunits of ribulose bisphosphate carboxylase (RuBP) were clearly observed. Both light and BA induced starch depletion and gratia formation after 12–24 h. BA was less efficient than light in inducing thylakoid formation and more efficient in inducing starch depletion. After 6 h both factors induced the appearance of the same new polypeptides in the 28–53 kDa range. Most prominent among them is a 32 kDa band. Light is much more effective in inducing the formation of a 29 kDa band than is BA. In mature chloroplasts this band stains very strongly, while the 32 kDa band disappears. We suggest that the 29 kDa polypeptide is the light harvesting complex (LHC), since a purified LHC preparation from cotyledons grown either on water in light or on BA in the dark migrates on the polyacrylamide gel as a single 29 kDa band. 相似文献
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Effect of polyunsaturated fatty acids on endocannabinoid and N-acyl-ethanolamine levels in mouse adipocytes 总被引:1,自引:0,他引:1
Matias I Carta G Murru E Petrosino S Banni S Di Marzo V 《Biochimica et biophysica acta》2008,1781(1-2):52-60
The tissue concentrations of the endocannabinoids, 2-arachidonoylglycerol (2-AG) and N-arachidonoyl-ethanolamine (anandamide), are altered in the adipose tissue of mice fed a high fat diet. We have investigated here the effect on endocannabinoid levels of incubation of mouse 3T3-F442A adipocytes with several free polyunstaurated fatty acids (PUFAs), including linolenic acid (LA), alpha-linolenic acid (ALA), arachidonic acid (AA) and docosahexaenoic acid (DHA), as well as oleic acid (OA) and palmitic acid (PA). By using mass spectrometric methods, we quantified the levels of endocannabinoids, of two anandamide congeners, N-palmitoyl-ethanolamine (PEA) and N-oleoyl-ethanolamine (OEA), and of fatty acids esterified in triacylglycerols or phospholipids, which act as 2-AG and/or N-acyl-ethanolamine precursors. Incubation with AA strongly elevated 2-AG levels and the amounts of AA esterified in triacylglycerols and on glycerol carbon atom 2 (sn-2), but not 1 (sn-1), in phospholipids. Incubation with DHA decreased 2-AG and anandamide levels and the amounts of AA esterified on both the sn-2 and sn-1 position of phospholipids, but not on triacylglycerols. PEA levels augmented following incubation of adipocytes with OA and PA, with no corresponding changes in phospholipids and triacylglycerols. We suggest that dietary PUFAs might modulate the levels of adipocyte phospholipids that act as endocannabinoid precursors. 相似文献
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Martelli AM Billi AM Manzoli L Faenza I Aluigi M Falconi M De Pol A Gilmour RS Cocco L 《FEBS letters》2000,486(3):230-236
Using NIH 3T3 cells, we have investigated nuclear phosphoinositide metabolism in response to insulin, a molecule which acts as a proliferating factor for this cell line and which is known as a powerful activator of the mitogen-activated protein (MAP) kinase pathway. Insulin stimulated inositol lipid metabolism in the nucleus, as demonstrated by measurement of the diacylglycerol mass produced in vivo and by in vitro nuclear phosphoinositide-specific phospholipase C (PI-PLC) activity assay. Despite the fact that nuclei of NIH 3T3 cells contained all of the four isozymes of the beta family of PI-PLC (i.e. beta1, beta2, beta3, and beta4), insulin only activated the beta1 isoform. Insulin also induced nuclear translocation of MAP kinase, as demonstrated by Western blotting analysis, enzyme activity assays, and immunofluorescence staining, and this translocation was blocked by the specific MAP kinase kinase inhibitor PD98059. By means of both a monoclonal antibody recognizing phosphoserine and in vivo labeling with [(32)P]orthophosphate, we ascertained that nuclear PI-PLC-beta1 (and in particular the b subtype) was phosphorylated on serine residues in response to insulin. Both phosphorylation and activation of nuclear PI-PLC-beta1 were substantially reduced by PD98059. Our results conclusively demonstrate that activation of nuclear PI-PLC-beta1 strictly depends on its phosphorylation which is mediated through the MAP kinase pathway. 相似文献
36.
Ninfali P Perini MP Bresolin N Aluigi G Cambiaggi C Ferrali M Pompella A 《Life sciences》2000,66(6):PL85-PL91
Divicine is an aglycone derived from vicine, a glucosidic compound contained in fava beans (Vicia faba major or broad beans). In this study, we investigated the effect of divicine on cultured human myoblasts from normal subjects, in order to see if the drug may induce signs of oxidant stress in these cells. Myoblasts incubated 24 hours in the presence of 1 mM divicine, showed an increase of carbonyl groups and 4-hydroxynonenal (4-HNE) bound to cell proteins, as well as a significant release of iron and lactate dehydrogenase in the culture medium. Desferrioxamine (DFO), an iron chelator, significantly prevented protein oxidation and formation 4-HNE adducts. Our results can be interpreted as indicating that divicine autooxidizes both at extracellular level and into myoblasts thus inducing the release of free iron, which initiates oxidation of cellular proteins and lipids. DFO protects the cells by subtracting the free iron both at intracellular and extracellular level. 相似文献
37.
In Vitro Evaluation of Different Methods of Handling Human Liposuction Aspirate and Their Effect on Adipocytes and Adipose Derived Stem Cells
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Paola Palumbo Gianfranca Miconi Benedetta Cinque Cristina la Torre Francesca Lombardi Giovanni Zoccali Gino Orsini Pietro Leocata Maurizio Giuliani Maria Grazia Cifone 《Journal of cellular physiology》2015,230(8):1974-1981
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The oxygen radical absorbance capacity (ORAC) was measured both in whole (ORAC-T) and deproteinized (ORAC-AS) plasma samples of human, pig, cow, rabbit, dog, cat, sheep, horse, dolphin, turkey, guineahen and chicken. In the 12 species, ORAC-T data, expressed as micromoles of peroxyl radicals trapped by 11 of sample, were found scattered between 8,600 and 23,000 μmol/1. The species with the highest ORAC-T values were cat among mammals and chicken among avies. ORAC-AS values ranged between 600 and 2000 μmol/1, with the highest values found in dolphin and sheep among mammals, while chicken was first among avies. In the 12 species, the relative contribution of ORAC-AS in relation to ORAC-T ranged from 5% to 20%. Protein SH-groups and uric acid were measured in plasma of all species, but no significant correlation was found between thiols and ORAC-T values or between uric acid and ORAC-AS values. Our results show that: (1) the ORAC method is reproducible and sensitive enough to be used in the comparison of the peroxyl-radical absorbance capacity of protein and non-protein plasma components in different animal species; (2) both in mammals and in avies, there is a deep intra-class heterogeneity of ORAC-T and ORAC-AS values; (3) by considering most species, plasma proteins and lipoproteins account for about 85-90% of the overall peroxyl-radical trapping capacity. In the dolphin only, the protein contribution decreases to 80%; (4) uric acid accounts for about one-half of the ORAC-AS value in human, guinea-hen and for about one-third in chicken, while it provides a very limited contribution in other species. We conclude that species with the highest ORAC-T, like cat and chicken, or with the highest ORAC-AS, like dolphin, are interesting models to study the reasons of such a marked antioxidant defense in the plasma. 相似文献
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