Enhanced Transferrin Receptor Expression by Proinflammatory Cytokines in Enterocytes as a Means for Local Delivery of Drugs to Inflamed Gut Mucosa

Therapeutic intervention in inflammatory bowel diseases (IBDs) is often associated with adverse effects related to drug distribution into non-diseased tissues, a situation which attracts a rational design of a targeted treatment confined to the inflamed mucosa. Upon activation of immune cells, transferrin receptor (TfR) expression increases at their surface. Because TfR is expressed in all cell types we hypothesized that its cell surface levels are regulated also in enterocytes. We, therefore, compared TfR expression in healthy and inflamed human colonic mucosa, as well as healthy and inflamed colonic mucosa of the DNBS-induced rat model. TfR expression was elevated in the colonic mucosa of IBD patients in both the basolateral and apical membranes of the enterocytes. Increased TfR expression was also observed in colonocytes of the induced colitis rats. To explore the underlying mechanism CaCo-2 cells were treated with various proinflammatory cytokines, which increased both TfR expression and transferrin cellular uptake in a mechanism that did not involve hyper proliferation. These findings were then exploited for the design of targetable carrier towards inflamed regions of the colon. Anti-TfR antibodies were conjugated to nano-liposomes. As expected, iron-starved Caco-2 cells internalized anti-TfR immunoliposomes better than controls. Ex vivo binding studies to inflamed mucosa showed that the anti-TfR immunoliposomes accumulated significantly better in the mucosa of DNBS-induced rats than the accumulation of non-specific immunoliposomes. It is concluded that targeting mucosal inflammation can be accomplished by nano-liposomes decorated with anti-TfR due to inflammation-dependent, apical, elevated expression of the receptor

Physico-chemical quality and homogeneity of folic acid and iron in enriched flour using principal component analysis

The aim of the present work was to determine parameters of the corn and wheat flour matrix, such as protein, lipid, moisture, ash and carbohydrates, folic acid and iron contents. Three principal components explained 91% of the total variance. Wheat flours were characterized by high protein and moisture content. On the other hand, the corn flours had the greater carbohydrates, lipids and folic acid levels. The concentrations of folic acid were lower than the issued value for wheat flours. Nevertheless, corn flours presented extremely high values. The iron concentration was higher than that recommended in Brazilian legislation. Poor homogenization of folic acid and iron was observed in enriched flours. This study could be useful to help the governmental authorities in the enriched food programs evaluation.6016417

Metabolic fingerprinting of royal jelly: characterization and proof of authenticity

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Introduction Metabolic fingerprint is a high-throughput screening to provide a sample classification. Objectives Herein, we describe a metabolic fingerpint strategy for proof of authenticity and possible adulteration of natural products. This strategy provides useful and complementary information to food science for content analysis. Methods Twelve samples of commercial royal jelly were analysed by electrospray ionization mass spectrometry (ESI-MS) in the negative mode. ESI-MS/MS was performed for characteristic negatively charged ions. Results Thermostability studies were also performed to royal jelly samples in order to evaluate the change on chemical composition with different times of exposure to heating and storage at room temperature. Conclusion The methodology developed in this work is useful to proof of authenticity and degradation of royal jelly samples using minimum sample preparation and direct injection of extracts.34185190Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES

Interferon-gamma (IFN-γ) and prostaglandin E2(PGE2) regulate differently IL-12 production in human intestinal lamina propria mononuclear cells (LPMC)

IL-12 modulates Th1 immune response during chronic colitis. Mechanisms regulating IL-12 synthesis in human intestine are poorly understood. The aim of this study was to investigate the effect of IFN-γ and PGE2 on lipopolysaccharide (LPS)-stimulated LPMC IL-12 production. Normal LPMC cultures were run in the presence or absence of IFN-γ and/or PGE2 before LPS stimulation. To examine the role of endogenous PGE2 on LPS-stimulated IL-12 release, LPMC cultures were added of indomethacin before LPS stimulation. IL-12, IL-10 and IL-8 were measured by ELISA. No IL-12 was detected in either unstimulated or LPS-stimulated LPMC cultures. In contrast, LPMC released IL-8 (650 ± 125 pg/ml) and IL-10 (75 ± 25 pg/ml) in response to LPS. Treatment of LPMC with IFN-γ facilitated LPS-stimulated IL-12, whereas it completely abrogated IL-10 production. IL-12 release by LPMC stimulated with IFN-γ and LPS was significantly inhibited by exogenous IL-10. The addition of PGE2 to IFN-γ-treated LPMC cultures inhibited in a dose-dependent manner LPS-induced IL-12 secretion. Furthermore, IL-12 was detectable (85 ± 25 pg/ml) in the supernatants of LPMC cultures treated with indomethacin and LPS. In contrast to the effect on IL-12, PGE2 significantly augmented LPS-stimulated LPMC IL-10 production. However, the inhibition of IL-12 by PGE2 was only partially reversed by anti-IL-10. In a simplified model of LPS tolerance, we finally showed that monocyte-derived macrophages exhibited reduced IL-12 production after repeat LPS stimulation. In these cell cultures, indomethacin abrogated the induction of LPS desensitization. IFN-γ and PGE2 modulate differently the LPMC responsiveness to LPS in terms of IL-12 synthesis