Effects of glutamine on the nuclear factor-kappaB signaling pathway of murine peritoneal macrophages

The aim of this study was to evaluate the effect of glutamine on the expression of proteins involved in the nuclear factor-kappaB (NF-kappa B) signaling pathway of murine peritoneal macrophages. Since glutamine is essential for the normal functioning of macrophages, it was hypothesized that in vitro glutamine supplementation would increase NF-kappa B activation. Peritoneal macrophages were pretreated with glutamine (0, 0.6, 2 and 10 mM) before incubation with lipopolysaccharide (LPS), and the effects of glutamine on the production of tumor necrosis factor-alpha and on the expression and activity of proteins involved in the NF-kappa B signaling pathway were studied by an enzyme linked immuno-sorbent assay, Western blotting, and an electrophoretic mobility shift assay. Glutamine treatment (2 and 10 mM) increased the activation of NF-kappa B in LPS-stimulated peritoneal macrophages (P < 0.05). In non-stimulated cells, glutamine treatment (2 and 10 mM) significantly reduced I kappa B-alpha protein expression (P < 0.05). Glutamine modulates NF-kappa B signaling pathway by reducing the level of I kappa B-alpha, leading to an increase in NF-kappa B within the nucleus in peritoneal macrophages.

Effects of Protein-Energy Malnutrition on NF-KappaB Signalling in Murine Peritoneal Macrophages

Protein-energy malnutrition (PEM) is an important public health problem affecting millions of people worldwide. PEM decreases resistance to infection, impairing a number of physiological processes. In unstimulated cells, NF-kappa B is kept from binding to its consensus sequence by the inhibitor I kappa B alpha, which retains NF-kappa B in the cytoplasm. Upon various signals, such as lipopolysaccharide (LPS), I kappa B alpha is rapidly degraded and NF-kappa B is induced to translocate into the nucleus, where it activates expression of various genes that participate in the inflammatory response, including those involved in the synthesis of TNF-alpha. TRAF-6 is a cytoplasmic adapter protein that links the stimulatory signal from Toll like receptor-4 to NF-kappa B. The aim of this study was to evaluate the effect of malnutrition on induction of TNF-a by LPS in murine peritoneal macrophages. We evaluated peritoneal cellularity, the expression of MyD88, TRAF-6, IKK, I kappa B alpha and NF-kappa B, NF-kappa B activation and TNF-alpha mRNA and protein synthesis inmacrophages. Two-month-old male BALB/Cmice were submitted to PEM with a low-protein diet that contained 2% protein, compared to 12% protein in the control diet. When the experimental group had lost about 20% of the original body weight, it was used in the subsequent experiments. Malnourished animals presented anemia, leucopenia and severe reduction in peritoneal cavity cellularity. TNF-a mRNA and protein levels of macrophages stimulated with LPS were significantly lower in malnourished animals. PEM also decreased TRAF-6 expression and NF-kappa B activation after LPS stimulation. These results led us to conclude that PEM changes NF-kappa B signalling pathway in macrophages to LPS stimulus.

Hypoxia Inducible Factor-Dependent Regulation of Angiogenesis by Nitro-Fatty Acids

Objective-Nitro-fatty acids (NO(2)-FAs) are emerging as a new class of cell signaling mediators. Because NO(2)-FAs are found in the vascular compartment and their impact on vascularization remains unknown, we aimed to investigate the role of NO(2)-FAs in angiogenesis. Methods and Results-The effects of nitrolinoleic acid and nitrooleic acid were evaluated on migration of endothelial cell (EC) in vitro, EC sprouting ex vivo, and angiogenesis in the chorioallantoic membrane assay in vivo. At 10 mu mol/L, both NO(2)-FAs induced EC migration and the formation of sprouts and promoted angiogenesis in vivo in an NO-dependent manner. In addition, NO(2)-FAs increased intracellular NO concentration, upregulated protein expression of the hypoxia inducible factor-1 alpha (HIF-1 alpha) transcription factor by an NO-mediated mechanism, and induced expression of HIF-1 alpha target genes, such as vascular endothelial growth factor, glucose transporter-1, and adrenomedullin. Compared with typical NO donors such as spermine-NONOate and deta-NONOate, NO(2)-FAs were slightly less potent inducers of EC migration and HIF-1 alpha expression. Short hairpin RNA-mediated knockdown of HIF-1 alpha attenuated the induction of vascular endothelial growth factor mRNA expression and EC migration stimulated by NO(2)-FAs. Conclusion-Our data disclose a novel physiological role for NO(2)-FAs, indicating that these compounds induce angiogenesis in an NO-dependent mechanism via activation of HIF-1 alpha. (Arterioscler Thromb Vasc Biol. 2011;31:1360-1367.)

Malnourished mice display an impaired hematologic response to granulocyte colony-stimulating factor administration

The aim of this Study was to determine if protein-energy malnutrition Could affect the hematologic response to granulocyte colony-stimulating factor (G-CSF). Swiss mice were fled a low-protein diet containing 4% protein, whereas control mice were fed a 20% protein-containing diet. After the malnourished group lost 20% of their original body weight, the mice were subdivided in 2 treatment groups, and hematopoietic parameters were studied. Mice were injected with either 8 mu g/kg per day of G-CSF or saline twice daily for 4 days. Malnourished mice developed anemia with reticulopenia and leukopenia with depletion of granulocytes and lymphocytes. Both malnourished and control mice treated with G-CSF showed a significant increase in neutrophils; however, in the control group, this increase was more pronounced compared to the malnourished group (4.5-fold and 3.4-fold, respectively). Granulocyte colony-stimulating factor administration increased bone marrow blastic (P < .001) and granulocytic (P < .01) compartments in the controls bill had no significant effect oil these hematopoietic compartments in the Malnourished animals (P = .08 and P = .62, respectively). We report that malnourished mice display an impaired response to G-CSF, which contributes to the decreased production of leukocytes in protein-energy malnutrition. (C) 2008 Elsevier Inc. All rights reserved.

In Vitro Sun Protection Factor Evaluation of Sunscreens Containing Rutin and its Derivative

This research aimed at determining spectrophotometrically (290 to 320nm) the in vitro Sun Protection Factor (SPF) of sunscreens developed with rutin (R) or succinate rutin (SR), in association or not with UVB filter. Formulations were developed based on phosphate-base O/W emulsions, with (B) or not (A) the presence of polyacrylamide/C13-14 isoparaffin/laureth-7 (PIL), in accordance with the following associations: (a) control; (b) 1.0 % SR; (c) 0.1 % R; (d) 7.5 % ethylhexyl methoxycinnamate (EHMC); (e) 7.5 % EHMC + 0.1 % RS; (0 7.5 % EHMC + 0.1 % R. It was verified a statistical significative elevation of the SPF from 13.93 +/- 0.02 (Af) to 16.63 +/- 0.27 (Bf) and also in relation to 15.53 +/- 0.14 (Bd). According to the results, the EHMC had distinct behavior depending on the presence of bioactive substance and viscosity agent, thus, rutin obtained better profile as a SPF booster in these experimental conditions with the presence of PIL.