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881.
Improvement of Metabolic and Histological Changes of Adiposity in Rats by Synthetic Oleoyl Chalcones
Azza A. M. AlKhathami Hosam A. Saad Fareed A. Fareed Eman S. El-Shafey Eslam S. Elsherbiny Mamdouh R. El Nahas Mohamed R. E. Aly 《化学与生物多样性》2023,20(2):e202200670
We previously reported that synthetic oleoyl chalcones had a favorable effect to alleviate metabolic consequences of obesity in male SD rats. In this work, we prepared and characterized by spectroscopic tools, a set of six oleoyl chalcones ( 5a–c , 10 and 11a,b ). The comparative effects of the previously prepared oleoyl chalcones and their new synthetic analogs on metabolic and histological changes in obese male SD rats were studied. It was found that the oleoyl chalcones IIIa and IV were the best in improving many metabolic parameters, e. g., FBG, FI, ISI, TG, and total cholesterol. They cured systemic inflammation, through inhibition of the TNF-α and induction of adiponectin production. Moreover, chalcones IIIa and IV alleviated the oxidative stress accompanying obesity through the induction of the antioxidant enzymes GPX, SOD and CAT besides, GSH. Interestingly, chalcones IIIa and IV exerted hepatoprotective potency and ameliorated the manifestations of NAFLD via inhibition of apoptosis and induction of autophagy of hepatic cells. In conclusion, the oleoyl chalcones IIIa and IV were the most effective candidates among the series of synthetic chalcones in correcting body weight and the consequent metabolic and histological changes in adiposity. 相似文献
882.
Vânia Peretti de Albuquerque Wobeto João Agostinho Machado-Neto Tânia Regina Zaccariotto Daniela Maria Ribeiro Adriana da Silva Santos Duarte Sara Teresinha Olalla Saad Fernando Ferreira Costa Maria de Fatima Sonati 《Molecular and cellular biochemistry》2014,393(1-2):145-153
Characterized for the first time in erythrocytes, phosphatidylinositol phosphate kinases (PIP kinases) belong to a family of enzymes that generate various lipid messengers and participate in several cellular processes, including gene expression regulation. Recently, the PIPKIIα gene was found to be differentially expressed in reticulocytes from two siblings with hemoglobin H disease, suggesting a possible relationship between PIPKIIα and the production of globins. Here, we investigated PIPKIIα gene and protein expression and protein localization in hematopoietic-derived cells during their differentiation, and the effects of PIPKIIα silencing on K562 cells. PIPKIIα silencing resulted in an increase in α and γ globins and a decrease in the proliferation of K562 cells without affecting cell cycle progression and apoptosis. In conclusion, using a cell line model, we showed that PIPKIIα is widely expressed in hematopoietic-derived cells, is localized in their cytoplasm and nucleus, and is upregulated during erythroid differentiation. We also showed that PIPKIIα silencing can induce α and γ globin expression and decrease cell proliferation in K562 cells. 相似文献
883.
Saad Alshehri John Burgess Rudi van Eldik Colin D. Hubbard 《Inorganica chimica acta》1995,240(1-2):305-311
The kinetics of the reaction of cyanide ions with pentacyanoferrate(II) complexes have been studied spectrophotometrically at pressures of 1 bar and up to 1 kbar, at 298.2 K. An excess of cyanide ions was employed and first-order kinetics were observed both in aqueous solution and in aqueous-mono-ol mixtures. For several pyridine derivative leaving groups, neutral or mono-positively charged, the rate constant variation in aqueous medium is only over one half-order of magnitude, although thiourea and quinoxaline are much more labile, dissociating with rate constants about ten and three hundred times greater than this range, respectively. Very modest changes in rate constant are observed upon addition of 40% methanol, and in a few examples studied, kinetic differences become significant only in cosolvent-rich mixtures. Volumes of activation, Δ V*, are all positive, for reaction in water, confirming the expected bond extension of the leaving group in a D mechanism. Solvation changes and ligand differences do not wholly explain the variation in Δ V* values, or the changes in this parameter found when cosolvents are added. Reasonably good correlations are found for the logarithms of rate constants both with the pKa of the ligand and with Δ V*. Other potential correlations of the leaving group property and kinetic parameter are discussed. 相似文献
884.
Alberto Caldas Marie Jeanne Richard Saad Maniar Denise Laouari Michele Dechaux Alain Favier Claire Kleinknecht 《Biological trace element research》1992,32(1-3):339-348
The effects of chronic metabolic acidosis (CMA) on zinc (Zn) bone content and urinary excretion were examined in the presence
of normal or reduced renal function together with some aspects of calcium (Ca) metabolism. Four groups of rats were compared.
All were fed a 30% protein and 9 mg Zn/100 g diet. Two were uremic (U): The first developed acidosis (UA), which was suppressed
in the other (UNA) by NaHCO3 supplement. Two other groups had normal renal function: One was normal (CNA), and the other had NH4Cl in the drinking water and acidosis (CA).
Femur total Zn and Ca content was markedly reduced by CMA and was not affected by uremia. Zn urinary excretion was increased
by CMA and unaltered by uremia. Ca urinary excretion was markedly reduced in uremic rats, but was enhanced in both acidotic
conditions. Urinary Ca and Zn showed a strong correlation in uremic and in control rats. Plasma parathormone and 1,25(OH)2D3 were unchanged by CMA. These data are in agreement with a direct primary effect of CMA on bone in releasing buffers. CMA
induces bone resorption and a parallel decrease of mineral bone components, such as Ca and Zn, with little or no role of PTH,
1,25(OH)2D3 and of uremia itself. 相似文献
885.
886.
Coral Reefs - Hong Kong is considered to be a marginal area for coral growth due to its subtropical geography with relatively low winter sea temperatures. Corals can only form non-reefal... 相似文献
887.
Glutamine synthetase (GS) is a marker enzyme for Müller glia cells in neural retina. In chick embryo retina GS begins to increase sharply on the 16th day of development, but can be precociously induced by premature supply of the inducer, cortisol, already on the 8th day. At this stage GS inducibility is low, but it increases progressively with embryonic age. We investigated whether there was a corresponding age-dependent increase of cortisol-binding molecules (cortisol receptors) and found that their level is highest in the early retina and decreases with development. In light of this inverse relationship, we examined whether functional characteristics of these receptors change with age, but detected no differences. In in vitro tests, receptors from older retina translocated cortisol into nuclei from young retina, and vice versa, with similar effectiveness. Also, cortisol receptors from liver cells (which differ from retina receptors) can translocate the hormone into retina nuclei, and vice versa. These findings indicate that translocation of cortisol receptors is neither tissue-specific or age-dependent, nor is it conditional on the total amount of receptors normally present in cells. Therefore, the age-dependent increase of GS inducibility in embryonic retina cannot be directly related to quantitative or functional differences of cortisol receptors and is evidently controlled primarily at the gene level. The very large amount of cortisol-binding molecules in early embryonic retina raises the possibility that they play some role in early differentiation of retina cells unrelated to hormone binding. 相似文献
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