73 research outputs found

    Hypocholesterolaemic Activity of Lupin Peptides : Investigation on the Crosstalk between Human Enterocytes and Hepatocytes Using a Co-Culture System Including Caco-2 and HepG2 Cells

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    Literature indicates that peptic and tryptic peptides derived from the enzymatic hydrolysis of lupin protein are able to modulate cholesterol metabolism in human hepatic HepG2 cells and that part of these peptides are absorbed in a small intestine model based on differentiated human Caco-2 cells. In this paper, a co-culture system, including Caco-2 and HepG2 cells, was investigated with two objectives: (a) to verify whether cholesterol metabolism in HepG2 cells was modified by the peptides absorption through Caco-2 cells; (b) to investigate how lupin peptides influence cholesterol metabolism in Caco-2 cells. The experiments showed that the absorbed peptides, not only maintained their bioactivity on HepG2 cells, but that this activity was improved by the crosstalk of the two cells systems in co-culture. In addition, lupin peptides showed a positive influence on cholesterol metabolism in Caco-2 cells, decreasing the proprotein convertase subtilisin/kexin type 9 (PCSK9) secretion

    Soybean-and lupin-derived peptides inhibit DPP-IV activity on in situ human intestinal Caco-2 cells and ex vivo human serum

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    Recent investigations have focused on food-derived peptides as novel natural inhibitors of dipeptidyl peptidase IV (DPP-IV), a new target for diabetes. This study aimed to optimize fast, sensitive, and cost-effective DPP-IV assays in situ on human intestinal Caco-2 cells and ex vivo on human serum. Both assays were applied to investigate the inhibitory activity of soy and lupin peptides. The best conditions for in situ DPP-IV activity in Caco-2 cells were obtained using 2-day cells and 50 \ub5M Gly-Pro-AMC. Sitagliptin, used as reference inhibitor, showed a dose-dependent response with a 50% inhibition concentration (IC50) of 0.6 \ub5M. A lower IC50(0.2 \ub5M) was obtained for sitagliptin on human serum incubated with the substrate for 24 h. Both assays were applied to assess the activity of Lup1 (LTFPGSAED) and Soy1 (IAVPTGVA) on DPP-IV. Lup1 and Soy1 inhibited DPP-IV in situ, with IC50values of of 207.5 and 223.2 \ub5M, respectively, and maintained their inhibitory activity ex vivo on circulating DPP-IV with a slightly lower potency. These assays can be used to characterize the DPP-IV inhibitory activity of food-derived molecules more accurately than in vitro biochemical tests. This combined approach also considers their effects on the circulating form of DPP-IV, correlated to metabolic diseases

    Cadmium accumulation and interactions with zinc, copper, and manganese, analysed by ICP-MS in a long-term Caco-2 TC7 cell model

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    The influence of long-term exposure to cadmium (Cd) on essential minerals was investigated using a Caco-2 TC7 cells and a multi-analytical tool: microwave digestion and inductively coupled plasma mass spectrometry. Intracellular levels, effects on cadmium accumulation, distribution, and reference concentration ranges of the following elements were determined: Na, Mg, Ca, Cr, Fe, Mn, Co, Ni, Cu, Zn, Mo, and Cd. Results showed that Caco-2 TC7 cells incubated long-term with cadmium concentrations ranging from 0 to 10 lmol Cd/l for 5 weeks exhibited a significant increase in cadmium accumulation. Furthermore, this accumulation was more marked in cells exposed long-term to cadmium compared with controls, and that this exposure resulted in a significant accumulation of copper and zinc but not of the other elements measured. Interactions of Cd with three elements: zinc, copper, and manganese were particularly studied. Exposed to 30 lmol/l of the element, manganese showed the highest inhibition and copper the lowest on cadmium intracellular accumulation but Zn, Cu, and Mn behave differently in terms of their mutual competition with Cd. Indeed, increasing cadmium in the culture medium resulted in a gradual and significant increase in the accumulation of zinc. There was a significant decrease in manganese from 5 lmol Cd/l exposure, and no variation was observed with copper. Abbreviation: AAS – Atomic absorption spectrometry; CRM– Certified reference material; PBS – Phosphate buffered saline without calcium and magnesium; DMEM – Dubelcco’s modified Eagle’s medium

    Alexithymia in juvenile primary headache sufferers: a pilot study

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    Starting in the 1990s, there has been accumulating evidence of alexithymic characteristics in adult patients with primary headache. Little research has been conducted, however, on the relationship between alexithymia and primary headache in developmental age. In their research on alexithymia in the formative years, the authors identified one of the most promising prospects for research, as discussed here. The aim of this study was to verify whether there is: (a) a link between tension-type headache and alexithymia in childhood and early adolescence; and (b) a correlation between alexithymia in children/preadolescents and their mothers. This study was based on an experimental group of 32 patients (26 females and 6 males, aged from 8 to 15 years, mean 11.2 ± 2.0) suffering from tension-type headache and 32 control subjects (26 females and 6 males, aged from 8 to 15 years, mean 11.8 ± 1.6). Tension-type headache was diagnosed by applying the International Headache Classification (ICHD-II, 2004). The alexithymic construct was measured using an Italian version of the Alexithymia Questionnaire for Children in the case of the juvenile patients and the Toronto Alexithymia Scale (TAS-20) for their mothers. Higher rates of alexithymia were observed in the children/preadolescents in the experimental group (EG) than in the control group; in the EG there was no significant correlation between the alexithymia rates in the children/preadolescents and in their mothers

    Beliefs about memory among psychology students and their professors in psychodynamic clinical and experimental study programs

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    Introduction. \u2013 Research has shown that lay people, and even psychologists, may have distorted knowledge about memory functioning. May different study programs in psychology influence their ideas? Objective(s). \u2013 The study was aimed at evaluating psychology students\u2019 and psychology professors\u2019 knowledge about memory and factors potentially affecting the accuracy of episodic memory reports in clinical and legal contexts. Method. \u2013 A questionnaire was administered to introductory and advanced students of psychology enrolled at different curricula \u2013 experimental psychology and clinical psychology with a psychoanalytical orientation \u2013 and to professors teaching the courses in the same curricula. Results. \u2013 Results showed that advanced students and professors in experimental psychology have higher general knowledge of factors influencing memory performance than their peers, including memory issues of particular relevance to clinical psychology; no difference between the curricula was found for the introductory students. Conclusion. \u2013 The results are discussed in terms of the risks that the lack of knowledge on memory functioning of the psychologists with a psychodynamic orientation may have in producing wrong reports in forensic contexts
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