Dietary fiber intake leading to short-chain fatty acid (SCFA) production could be a strategy to combat intermittent bouts of inflammation during ulcerative colitis.
Our objective was to evaluate ...dietary potato fiber (PF) in attenuating inflammation using a dextran sodium sulfate (DSS)-induced colitis mouse model. We hypothesized that PF would show anti-inflammatory effects compared with cellulose due in part to SCFA production.
Male C57Bl/6J mice were fed diets containing either 8% cellulose or 14.5% PF for a 22-d feeding study. Starting on study day 14, mice were provided either distilled water (control) or 2% (wt:vol) DSS in drinking water for 5 d (cellulose+control, n = 17; PF+control, n = 16; cellulose+DSS, n = 17; and PF+DSS, n = 16). Body weights and food and water intakes were collected daily from day 14 through day 22. Distal colon tissue was analyzed for histologic outcomes and changes in gene expression, and cecal contents were analyzed for SCFA concentrations. Data were analyzed by ANOVA, with repeated measures applied where necessary.
At day 5 post-DSS induction, cellulose+DSS mice exhibited a 2% reduction (P < 0.05) in body weight compared with PF+DSS and PF+ and cellulose+control mice. PF+DSS mice had greater (P < 0.05) cecal butyrate concentrations 24.5 μmol/g dry matter (DM) than did cellulose+DSS mice (4.93 μmol/g DM). Mice fed PF+DSS had lower (P < 0.05) infiltration of leukocytes in the distal colon than did mice fed cellulose+DSS (mean histology scores of 1.22 and 2.30, respectively). Furthermore, mice fed cellulose+DSS exhibited 1.42, 11.5, 8.48, and 35.5 times greater (P < 0.05) colon mRNA expression of tumor necrosis factor α (Tnfa) and interleukin (Il) 1b, Il6, and Il17a, respectively, and 7.10 times greater (P < 0.05) expression of C-X-C motif ligand 1 (Cxc1) compared with mice fed PF+DSS.
These results suggest that PF fed to mice before and during DSS colitis attenuates inflammation, potentially through SCFA production; however, future studies are needed to understand the role of dietary fiber intake and immune activation.
Abstract Objective Acrylamide is a neurotoxic, genotoxic substance present in many commonly consumed food products and has been shown to have carcinogenic effects in rodents. The protective effects ...(if any) of potato fiber preparations, composed of cell wall material from potatoes, against the toxic influence of dietary acrylamide on the small intestinal wall were investigated. Methods Male mice of the BALB/c strain were used in the study. Acrylamide was administered to the mice in their drinking water (0.5 mg/kg of body weight per day) and one of two types of potato fiber preparations (heated or raw potato fiber preparation) was added to their feed (2% addition to their feed). Histomorphometry of the small intestinal wall, hemoglobin adducts of acrylamide, animal weight, and feed and water consumption analyses were performed. Results Acrylamide altered the morphology and histology of the small intestinal wall, decreasing proliferation, myenteron and submucosal thicknesses, villus length, fractal dimension, crypt depth, crypt number, and the small intestinal absorptive surface. Conversely, apoptosis, hemoglobin adduct levels, intensity of epithelium staining, enterocyte number, villus epithelial thickness, and crypt width and parameters associated with nerve ganglia were increased. The two potato fiber preparations that were used abolished the negative influences of acrylamide on the small intestinal wall and had no influence on the hemoglobin adduct levels of acrylamide. Conclusion The negative impact of acrylamide on the histologic structure, regeneration, and innervation of the small intestinal wall and the absorptive function of the small intestinal mucosa can be abolished by dietary potato fiber preparations.
•Roasted Potex extract contains both high and low molecular weight melanoidins.•Heated potato fiber extract inhibits proliferation of colon cancer cells in vitro.•High and low molecular weight ...melanoidins are responsible for the antiproliferative activity in colon cancer cells.
Melanoidins are brown, nitrogen containing, high molecular weight end products of Maillard reaction with poorly established activity towards tumor cells. The goal of present study was to verify whether both heated potato fiber Potex extract (180°C for 2h) and melanoidins isolated from the extract exerts growth-inhibiting activity in human colon cancer cells in vitro. The cells of LS180 colon cancer cell line were tested upon treatment with roasted potato fiber extract (AM4) as well as with high (HMW) and low (LMW) molecular weight fractions isolated from the extract, since both may be regarded as/or contain melanoidins. The tested compounds at concentration of 1000μg/ml reduced cell growth down to 45%, 69% and 54%, respectively. Furthermore, deregulated ERK1/2 signaling was revealed upon treatment. Moreover, multiple alternations in cell cycle regulators activity were found (i.e. cyclinD1, cyclin-dependent kinase 4 and 6, p21, p27, p53, pRb) leading to cell cycle cessation in G0 phase. Importantly, LMW compounds revealed markedly stronger potential to alter specific molecular targets comparing to HMW compounds. Summarizing, the results emphasize that both high and low molecular weight melanoidins contribute to antiproliferative activity of heated potato fiber in LS180 colon cancer cells in vitro.
Potex constitutes a potato fiber preparation widely used as an ingredient to meat and bakery products which thermal treatment results in creation of new compounds. Melanoidins are high molecular ...weight brown end products of Maillard reaction, and few data presenting tumor cell growth inhibiting activity of melanoidins have been reported. Thus, in present study we utilized water extract of Potex roasted (180 °C for 2 h), whose chemical characterization revealed the presence of melanoidin complexes. Heated Potex extract inhibited C6 glioma cell proliferation in a dose-dependent manner measured by MTT method. High molecular weight components present in initial extract were responsible for stronger antiproliferative effect compared with low molecular weight fraction. Impaired MAPK (mitogen-activated protein kinase) and Akt signaling was found in cells treated with the extract. Moreover, flow cytometry analyses revealed the extract to induce G1/S arrest in glioma cells. Simultaneously, Western blot analysis showed elevated levels of p21 protein with concomitant decrease of cyclin D1. In conclusion, observed antiproliferative activity of melanoidins present in heated Potex was linked to disregulated MAPK and Akt signaling pathways, as well as to cell cycle cessation. These results suggest potential application of Potex preparation as a functional food ingredient and chemopreventive agent.
Background: Macrophages play an important role as part of the innate immune response in the gut and they represent one of the first lines of nonspecific defense against bacterial invasion. Previous ...studies indicated that probiotics and prebiotics may act as an immunomodulator agents. Nevertheless, research on the immunomodulatory effect of local materials has never been performed.Objective: To study the effects of Lactobacillus plantarum Mut7 and sweet potato fiber on the activity and Nitric Oxide (NO) production of peritoneal macrophages of Sprague Dawley rats.Method: Ninety six Sprague Dawley rats aged 8 weeks were divided into two groups; A (not infected with Salmonella typhimurium) and B (infected with S. typhimurium). Each group was divided into 4 subgroups and assigned to standard AIN-93M diet (KON), 109 CFU/ml of L. plantarum Mut7 (PRO), modified AIN-93M diet with sweet potato fiber (PRE), and both component (SIN). After 3 weeks of treatment, 6 rats of each subgroup were sacrificed and the peritoneal macrophages were isolated and analysed for its activity and NO production. The rest of the rats continued the treatments for another 2 weeks. At the end of the experiment, they were sacrificed and the peritoneal macrophage were isolated and analysed for its activity and NO production.Results: Oral administration of L. plantarum Mut7, sweet potato fiber, or both improve phagocytic activity of peritoneal macrophage which was indicated by an increase in the percentage of macrophages that phagocyte latex particles (p<0.05) and an increase in the number of latex particles engulfed by macrophages either after 3 or 5 weeks of treatment (p<0.05). Oral administration of L. plantarum Mut7, sweet potato fiber, or both were unable to increase the nitric oxide production after 3 weeks of treatment (p>0.05), but after 5 weeks of treatment the production of NO was significantly increased (p<0.05).Conclusion: L. plantarum Mut7, sweet potato fiber, or both increase the non specific immune response as they could improve the activity and NO production of peritoneal macrophages.
The influence of the addition of carbohydrates with different physicochemical properties on weight loss and formation of heterocyclic amines (HAs) during the frying of beef burgers was examined. ...Furthermore, the capability of carbohydrates to bind HAs was tested. Beef burgers containing 1.5% NaCl and 0.3% tripolyphosphate (reference), with the addition of 1.5% carbohydrate, were fried for 5 min at 200 °C in a double-sided pan fryer. The beef burgers were analyzed for HAs with solid phase extraction and liquid chromatography/mass spectrometry. 2-Amino-3,8-dimethylimidazo4,5-fquinoxaline (MeIQx), 2-amino-3,4,8-trimethylimidazo4,5-fquinoxaline (4,8-DiMeIQx), 2-amino-1-methyl-6-phenyl-imidazo4,5-bpyridine (PhIP), and 9H-pyrido3,4-bindole (Norharman) were detected in all of the beef burgers. The addition of carbohydrates affected both the weight loss and the formation of HAs during cooking. The formation of HAs could be correlated to depend on both the weight loss and the type of the added carbohydrate. Of the 11 different carbohydrates tested, raw potato starch was most capable of inhibiting the formation of HAs, while potato fiber gave the lowest weight loss and a comparably low amount of PhIP. Wheat bran and potato fiber were found to reversibly bind HAs. It is concluded that adding small amounts of certain carbohydrates may be a simple and effective way of reducing the amount of HAs and can easily be applied in households and commercial preparations of beef burgers. Keywords: Heterocyclic amines; beef burger; frying; carbohydrates; water holding; PhIP; MeIQx; 4,8-DiMeIQx; Harman; Norharman
The cholesterol-lowering and hypoglycemic effect of dietary fiber are commonly attributed to soluble fiber fractions. By enzymatic treatment of potato pulp, which is rich in cellulose and pectin, we ...prepared 3 fractions with different chemical composition and solubility, and compared their effects with commercially available crystalline cellulose (negative control) on central parameters related to risk factors of diabetes mellitus and cardiovascular disease in diabetic prone Goto-Kakizaki rats. Forty male rats were fed a semisynthetic Western-type diet containing 5% dietary fiber in the form of concentrated potato fiber (CF), insoluble potato fiber (IF), soluble fiber (SF), or cellulose (CEL) ad libitum for 4.5 weeks to study weight change and induce diabetic conditions. This was followed by 16 days of slightly restricted feeding, for the measurement of fecal organic matter digestibility, fecal dry matter, urinary glucose excretion, and fasting blood glucose. Finally, the rats were euthanized 2 hours postprandial for measurement of postprandial glucose, triacylglycerol and cholesterol levels, and cecal fermentation pattern to assess any relation between digestion processes and hematological risk markers. Diet SF had higher fecal organic matter digestibility and led to a significantly larger pool of organic acids with a higher proportion of propionate than the other diets. There was no difference in hematological parameters except for a small but significant reduction in postprandial plasma triacylglycerol concentration of rats fed diet SF compared to diet CEL and diet CF. In conclusion, increased fermentation and production of propionate with diet SF did not reduce plasma cholesterol or glycemic response.
In order to introduce a suitable drug mixing base or covering for burns or decubital wounds, the usefulness of fiber extracted from the sweet potato was investigated. The healing effect of the fiber ...was evaluated by examining the extent of reduction in the size of wounds and changes in the quality of wounds in rats. In contrast to the control, the use of the fiber alone as a wound covering material reduced wounded areas by 21.0% at postoperative day 9, 19.5% at day 11, and 18.7% at day 13, and resulted in an obvious increase in the rats' weight. The number of days required for healing in all treated rats was 19 for the fiber groups and over 21 d for the control. In vitro, the fiber indicated excellent absorptive ability for serum and good adhesive ability for a number of proteins. This result suggested that the fiber has favorable properties for healing wounds which contain large amounts of exudate. Our macroscopic findings also indicated that the fiber protected wounds from dryness. These results suggested that sweet potato fiber could be use as a covering material in combination with drugs in skin wound therapy.
To increase the utilization of side-streams from the food industry more investigations of multiple protein systems could be beneficial, complementary to the extensive studies available on single ...sourced protein isolates. Here, high moisture content protein-rich side streams were investigated in single screw extrusion. Vegetable protein mixtures comprising potato protein, oat protein and wheat bran were considered. Potato starch and potato fibers were used as structuring agents. Microstructurally, all compositions were dominated by protein aggregates. The structural agents enhanced the interconnected starch phase and/or additionally introduced fiber aggregates, with little apparent influence on the protein aggregates size and distribution. The moisture content was found to exert a dominant influence on the shear viscosity of the compositions. In addition, a saturation behavior of the power law parameters over 45% moisture content was apparent in the presence of the structural agents. An improved knowledge of industrial side-streams processability could increase their use in novel food products and exploited to create products with improved nutritional profiles.
•High moisture content protein-rich side streams were investigated in single screw extrusion.•Vegetable protein mixtures comprising of potato protein, oat protein and wheat bran were considered.•Potato starch and potato fibers were used as structuring agents.•In-line viscometry and microstructural characterization was performed and corroborated.
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