Nigella sativa inhibits intestinal glucose absorption and improves glucose tolerance in rats.

Aim Of The Study: Nigella sativa L. (Ranunculaceae) seeds have been used traditionally for centuries, notably for treating diabetes.

Materials And Methods: We studied the effects of the crude aqueous extract of Nigella sativa seeds on intestinal glucose absorption in vitro using a short-circuit current technique and in vivo using an oral glucose tolerance test.

Apical effect of diosmectite on damage to the intestinal barrier induced by basal tumour necrosis factor-alpha.

Background: In many digestive diseases the intestinal barrier is weakened by the release of proinflammatory cytokines, including tumour necrosis factor-alpha (TNF alpha).

Aim: To investigate the protective effect of apical diosmectite on the intestinal dysfunction induced by the proinflammatory cytokine TNF alpha.

Methods: Filter grown monolayers of the intestinal cell line HT29-19A were incubated for 48 hours in basal medium containing 10 ng/ml TNF alpha and 5 U/ml interferon-gamma (IFN gamma).

Deregulation of hexose transporter expression in Caco-2 cells by ras and polyoma middle T oncogenes.

We investigated whether the oncogenic activation of p21ras or pp60c-src, which is frequently observed in colorectal cancers, induced alterations of sugar uptake in human colonic cells. We therefore examined hexose transporter expression and/or activity in Caco-2 cells transfected either with an activated human (Val-12) Ha-ras gene or with the polyoma middle T (PyMT) oncogene, a constitutive activator of pp60c-src tyrosine kinase activity. Experiments were performed at day 20 of culture, when Caco-2 cells express enterocyte-specific GLUT-2, GLUT-5, and SGLT-1 transporters in addition to GLUT-1 and GLUT-3.

Regulation of expression of the human fructose transporter (GLUT5) by cyclic AMP.

The effect of cyclic AMP on the expression of the fructose transporter, GLUT5, was studied in Caco-2 cells, a human colon cancer cell line that differentiates spontaneously in culture into cells with the properties of small intestine enterocytes. Treatment of differentiated Caco-2 cells with 50 microM forskolin, which stimulates adenylate cyclase and raises intracellular cyclic AMP levels, increased fructose uptake 2-fold and raised GLUT5 protein and mRNA levels 5- and 7-fold respectively. The increased GLUT5 mRNA levels in forskolin-treated cells are a result of stabilization of GLUT5 mRNA in these cells and increased transcription.