Novel ex Vivo Experimental Setup to Assay the Vectorial Transepithelial Enteroendocrine Secretions of Different Intestinal Segments.

The enteroendocrine system coordinates gastrointestinal (GI) tract functionality and the whole organism. However, the scarcity of enteroendocrine cells and their scattered distribution make them difficult to study. Here, we glued segments of the GI wall of pigs to a silicon tube, keeping the apical and the basolateral sides separate. The fact that there was less than 1% of 70-kDa fluorescein isothiocyanate (FITC)-dextran on the basolateral side proved that the gluing was efficient. Since the lactate dehydrogenase leakage at basolateral side was lower than 0.1% (1.40 ± 0.17 nKatals) it proved that the tissue was viable. The intestinal barrier function was maintained as it is in segments mounted in Ussing chambers (the amount of Lucifer Yellow crossing it, was similar between them; respectively, % LY, 0.48 ± 0.13; 0.52 ± 0.09; p > 0.05). Finally, apical treatments with two different extract produced differential basolateral enterohormone secretions (basolateral PYY secretion vs control; animal extract, 0.35 ± 0.16; plant extract, 2.5 ± 0.74; p < 0.05). In conclusion, we report an ex vivo system called "Ap-to-Bas" for assaying vectorial transepithelial processes that makes it possible to work with several samples at the same time. It is an optimal device for enterohormone studies in the intestine.

Effectiveness of a low-fat yoghurt supplemented with rooster comb extract on muscle strength in adults with mild knee pain and mechanisms of action on muscle regeneration.

PURPOSE: To determine the effects of the intake of low-fat yoghurt supplemented with rooster comb extract (RCE) on muscle strength. METHODS AND RESULTS: 148 subjects, with mild knee pain, participated in a randomized, placebo-controlled, double-blind, and parallel study. Muscle strength, knee effusion, and pain perception were measured. C2C12 myoblasts were used to elucidate the mechanisms of action involved. RCE improved total work and mean power in men, and also peak torque in extension by 10%. RCE reduced synovial effusion by 11.8% and pain perception by 24.6%. Both RCE and HA increased myoblast proliferation by 29%, while RCE reduced myoblast differentiation by 36.2%, suggesting a beneficial role of RCE in muscle regeneration. CONCLUSIONS: Low-fat yoghurt supplemented with RCE improved muscle strength. This effect is partially explained by muscle regeneration enhancement, reduced synovial effusion, and reduced pain perception, which could exert a beneficial clinical impact on men affected by mild knee pain.

Antioxidant effects of a grapeseed procyanidin extract and oleoyl-estrone in obese Zucker rats.

OBJECTIVE: To substantiate the relation between obesity and oxidative stress and to assess the potential beneficial properties of a grapeseed proanthocyanidin extract (GSPE), the amelioration of obesity with oleoyl-estrone (OE), and the possible combined effect of GSPE and OE on the hepatic and renal antioxidant enzyme system in obesity-induced oxidative stress. METHODS: Male obese Zucker rats were divided into four groups: GSPE, OE, GSPE + OE, and OC (control). For 30 d they were gavaged with GSPE, OE, GSPE + OE, or sunflower oil as the control vehicle (OC). Lean Zucker rats gavaged with the vehicle comprised the lean control group. Hepatic and renal antioxidant enzymes and oxidative biomarkers were determined at the end of the experimental period. RESULTS: Hepatic antioxidant activities were higher in obese rats than in lean ones. All these activities decreased when obese rats were treated with GSPE, whereas only some of these activities decreased with OE and GSPE + OE treatments. In the kidney, few antioxidant enzymes had higher activities in obese than in lean rats, and OE and GSPE + OE were the treatments that inhibited most enzymes studied. Glutathione S-transferase activity was always lower with the exception of the kidney of obese rats and all treatments used increased the low glutathione levels found in obesity. CONCLUSION: GSPE and OE improve oxidative stress in obese Zucker rats. The effect of GSPE + OE is comparable to GSPE for the liver and to OE for the kidney. Thus the effects of GSPE and OE are not additive and are organ dependent.

Inhibitory effects of grape seed procyanidins on foam cell formation in vitro.

Human and animal studies have demonstrated that procyanidin-rich diets reduce the risk of cardiovascular diseases and atherosclerosis. Some beneficial effects have been attributed to the well-known antioxidant activity of procyanidins. This study investigated another potential corrective role of procyanidins in cholesterol flux and inflammation in macrophage-derived foam cells. RAW 264.7 macrophages were cultured with moderately oxidized LDL (oxLDL), minimally oxidized LDL (moxLDL), or LPS (0.5 microg/mL) and oxLDL (LPS + oxLDL) to induce foam cells. Then, cells were treated with procyanidins derived from grape seed (PE, 45 microg/mL) for the last 12 h of incubation with the different lipoproteins (25 microg/mL). After lipid extraction, it was determined that total and esterified cholesterol and triglyceride accumulations in foam cells were increased by lipoprotein treatment but reduced by PE incubation. To asses the effect of PE on gene expression, the relative mRNA levels of CD36, ABCA1, iNOS, COX-2, and IkappaBalpha were determined by RT-PCR. It was shown that PE reduced the oxLDL scavenger receptor expression (CD36) and enhanced ATP-binding cassette A1 (ABCA1) expression, a key regulator of macrophage cholesterol efflux. PE also down-regulated inflammatory-related genes such as inducible nitric oxide synthase (iNOS) and kappa beta inhibitor-alpha (IkappaBalpha) without modifying COX-2 expression. In conclusion, evidence is provided that procyanidins may attenuate the development of foam cell formation by reducing cholesterol accumulation and modulating the expression of key genes in cholesterol flux and inflammation.