Calcium deficiency in the early stages after weaning is associated with the enhancement of a low level of adrenaline-stimulated lipolysis and reduction of adiponectin release in isolated rat mesenteric adipocytes
Shinoki A.,Laboratory of Nutritional Biochemistry |
Hara H.,Laboratory of Nutritional Biochemistry
Metabolism: Clinical and Experimental | Year: 2010
Dysregulation of visceral adipocytes increases the incidence of metabolic syndrome. Higher production of nonesterified fatty acid and changes in adipocytokine release may trigger insulin resistance. Many studies have suggested that calcium (Ca) deficiency is associated with insulin resistance; however, the mechanisms are poorly understood. We examined the effects of Ca deficiency on adrenaline-induced lipolysis and adipocytokine release in the early stages after weaning using freshly isolated adipocytes from mesenteric fat tissue of 3-week-old male Sprague-Dawley rats fed a normal-Ca (5 g/kg diet) or low-Ca (1 g/kg diet) diet for 4 weeks. The release rate of nonesterified fatty acid in the mesenteric adipocytes after stimulation with a low level of adrenaline (0.2 μg/mL) was much higher in the Ca-deficient group than in the control group. In contrast, adiponectin release in the mesenteric fat cells was lower in Ca-deficient rats. Leptin and tumor necrosis factor-α secretion showed a similar tendency without significant intergroup differences, and monocyte chemoattractant protein-1 release was not affected by Ca deficiency. We found that Ca deficiency reduced the average size of fat cells through a large increase in the number of cells slightly smaller than the average size, which may be associated with the changes in the properties of the mesenteric adipose tissue. Our present results suggest that a low intake of Ca in the early stages after weaning is associated with changes in the properties of mesenteric adipocytes, which may be linked to insulin resistance in the future. © 2010 Elsevier Inc. All rights reserved.
Teodoro A.J.,Laboratory of Nutritional Biochemistry |
Teodoro A.J.,Rio de Janeiro State Federal University |
Oliveira F.L.,Federal University of Rio de Janeiro |
Martins N.B.,Federal University of Rio de Janeiro |
And 3 more authors.
Cancer Cell International | Year: 2012
Background: Lycopene, a major carotenoid component of tomato, has a potential anticancer activity in many types of cancer. Epidemiological and clinical trials rarely provide evidence for mechanisms of the compound's action, and studies on its effect on cancer of different cell origins are now being done. The aim of the present study was to determine the effect of lycopene on cell cycle and cell viability in eight human cancer cell lines.Methods: Human cell lines were treated with lycopene (1-5 μM) for 48 and 96 h. Cell viability was monitored using the method of MTT. The cell cycle was analyzed by flow cytometry, and apoptotic cells were identified by terminal deoxynucleotidyl transferase-mediated dUTP nick labeling (TUNEL) and by DAPI.Results: Our data showed a significant decrease in the number of viable cells in three cancer cells lines (HT-29, T84 and MCF-7) after 48 h treatment with lycopene, and changes in the fraction of cells retained in different cell cycle phases. Lycopene promoted also cell cycle arrest followed by decreased cell viability in majority of cell lines after 96 h, as compared to controls. Furthermore, an increase in apoptosis was observed in four cell lines (T-84, HT-29, MCF-7 and DU145) when cells were treated with lycopene.Conclusions: Our findings show the capacity of lycopene to inhibit cell proliferation, arrest cell cycle in different phases and increase apoptosis, mainly in breast, colon and prostate lines after 96 h. These observations suggest that lycopene may alter cell cycle regulatory proteins depending on the type of cancer and the dose of lycopene administration. Taken together, these data indicated that the antiproliferative effect of lycopene was cellular type, time and dose-dependent. © 2012 Teodoro et al.; licensee BioMed Central Ltd.
Chikazawa M.,Nagoya University |
Otaki N.,Nagoya University |
Shibata T.,Nagoya University |
Miyashita H.,Nagoya University |
And 6 more authors.
Journal of Biological Chemistry | Year: 2013
Background: Advanced glycation end products (AGEs) can act as neoantigens to trigger immune responses. Results: Natural IgM antibodies against AGEs recognize multiple molecules, including DNA and chemically modified proteins. Conclusion: There is a close relationship between the formation of AGEs and innate immune responses. Significance: Our findings highlight AGEs and related modified proteins as a source of multispecific natural antibodies. Copyright © 2013 by The American Society for Biochemistry and Molecular Biology, Inc.