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Rye whole grain and bran intake has shown beneficial effects on prostate cancer progression in animal models, including lower tumor take rates, smaller tumor volumes, and reduced prostate specific antigen (PSA) concentrations. A human pilot study showed increased apoptosis after consumption of rye bran bread. In this study, we investigated the effect of high intake of rye whole grain and bran on prostate cancer progression as assessed by PSA concentration in men diagnosed with prostate cancer. Seventeen participants were provided with 485 g rye whole grain and bran products (RP) or refined wheat products with added cellulose (WP), corresponding to ~50% of daily energy intake, in a randomized controlled, crossover design. Blood samples were taken from fasting men before and after 2, 4, and 6 wk of treatment and 24-h urine samples were collected before the first intervention period and after treatment. Plasma total PSA concentrations were lower after treatment with RP compared with WP, with a mean treatment effect of -14% (P = 0.04). Additionally, fasting plasma insulin and 24-h urinary C-peptide excretion were lower after treatment with R P compared with WP (P < 0.01 and P = 0.01, respectively). Daily excretion of 5 lignans was higher after the RP treatment than after the WP treatment (P < 0.001). We conclude that whole grain and bran from rye resulted in significantly lower plasma PSA compared with a cellulose-supplemented refined wheat diet in patients with prostate cancer. The effect may be related to inhibition of prostate cancer progression caused by decreased exposure to insulin, as indicated by plasma insulin and urinary C-peptide excretion. J. Nutr. 140: 2180-2186, 2010. doi: 10.3945/jn.110.127688.

Background Control of body weight by balancing energy intake and energy expenditure is of major importance for the prevention of type 2 diabetes, but the role of specific dietary factors [...]

ABSTRACT Wheat bran was shown to provide protection against colorectal cancer in human intervention and animal studies. Our recent study showed, however, that antitumor activities of wheat bran from various wheat cultivars differed significantly even when wheat fiber was equal in diets. We hypothesized that phytochemical lignans in wheat bran may account for the differences among wheat cultivars in cancer prevention. The concentration of a major lignan, secoisolariciresinol diglycoside, was determined by HPLC in 4 selected wheat cultivars (i.e., Madison, Ernie, Betty, and Arapahoe). The lignan concentrations and their antitumor activities, previously determined in APC-Min mice, were correlated (r = 0.73, P < 0.02). The cancer preventive mechanisms of 2 prominent lignan metabolites (enterolactone and enterodiol) were further studied in human colonic cancer SW480 cells. Treatment with enterolactone and enterodiol, alone or in combination, at 0-40 [micro]mol/L resulted in dose- and time-dependent decreases in cell numbers. Although the cytotoxicity as measured by trypan blue staining in adherent cells was not affected, DNA flow cytometric analysis indicated that the treatments induced cell cycle arrest at the S-phase. Western blot analysis for cyclin A, a required protein for S/G2 transition, showed that the cyclin A protein levels decreased after treatment with enterodiol or the combination of enterolactone and enterodiol at 40 [micro]mol/L for 72 h. Apoptosis analysis by the terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling assay showed an increased percentage of apoptotic cells in the floating cells after enterodiol alone or combined treatments. These results suggest for the first time that lignans may contribute, at least in part, to the cancer prevention by wheat bran observed in APC-Min mice. Inhibition of cancer cell growth by lignan metabolites seems to be mediated by cytostatic and apoptotic mechanisms. KEY WORDS: * lignans * wheat bran * SW480 colon cancer cells * cell cycle arrest * apoptosis

To investigate the effects of dietary fibers in colonic luminal physiology and their role in the prevention of colon cancer, a study was conducted using two diet groups and two treatment groups in a 2 x 2 factorial design. The two diets differed only in the type of dietary fiber, wheat bran and oat bran, and the two treatments were injection with the colon-specific carcinogen azoxymethane, or saline, as a control. There were 34 rats in the carcinogen-injected groups and 11 saline-injected rats per diet group. The goal of the study was to determine if a moderate consumption (6 g/100 g diet) of wheat bran or oat bran would alter the development of colonic tumors in this rat model of colon cancer, and if the differences in tumor incidence were correlated to luminal butyrate concentrations, luminal pH or fecal bulk. Short-chain fatty acid concentrations (SCFA) were measured in feces during the first half of the study (the promotion phase of tumor development) and again at the end of the study. Rats consuming oat bran had greater body weights (P < 0.002), produced much larger concentrations of all SCFA, including butyrate, in both the proximal and distal colon (P < 0.0001), had more acidic luminal pH values (P < 0.0001), but also had significantly more development of colon tumors (P < 0.03). Alternatively, rats consuming wheat bran produced more typical molar ratios of the SCFA (65:10:20), had a relatively greater concentration of butyrate than propionate, and produced a larger volume (P < 0.05) and more bulky stool than the rats fed oat bran. The results of this study support other evidence that an acidic luminal pH is not protective in and of itself, and that diets containing wheat bran are protective against colon cancer development. In addition, these data show that large luminal butyrate concentrations in the distal colon alone, as were present in the rats consuming oat bran diets, are not protective of tumor development. KEY WORDS: colon cancer; luminal pH; butyrate; dietary fiber; rats

Byline: D. G. Gualberto (1), C. J. Bergman (1), M. Kazemzadeh (2), C. W. Weber (3) Keywords: Soluble fiber; Insoluble fiber; Bran; Extrusion; Oat; Rice; Wheat; Phytate Abstract: The health benefits associated with dietary fiber have resulted in it now being used in virtually all food product categories, including many products which are manufactured using extrusion processing. The objective of the present study was to determine if extrusion processing affected phytic acid, and soluble and insoluble fiber contents. The effect of screw speeds of 50, 70, and 100% of maximum rotations per minute (% MRPM) on these components was investigated. A BI-EX Model DNDG-62/20D co-rotating intermeshing self-cleaning twin-screw extruder, manufactured by Buhlerag, CH-9240, Uzwil, Switzerland, was used to process wheat, oat and rice brans. It was found that extrusion did not affect the insoluble fiber content of wheat bran however, a decrease in this component was observed in rice and oat brans. The effect on rice bran insoluble fiber was greatest at screw speeds of 50 and 70% MRPM. This occurred in oat bran at 50% MRPM. Soluble fiber content increased in all brans after extrusion, except ER.sub.100. For oat and rice bran soluble fibers, the greatest increase occurred at 50 and 70% MRPM, while for wheat bran this occurred at 70 and 100% MRPM. Extrusion did not affect the phytate content of the cereal brans. Author Affiliation: (1) Agricultural Research Service, Soft Wheat Quality Laboratory, US Department of Agriculture, 1680 Madison Avenue, Wooster, OH, 44691, USA (2) Buhler Inc., Minneapolis, MN, 55440, USA (3) Department of Nutrition and Food Science, University of Arizona, Tucson, AZ, 85721, USA Article History: Registration Date: 30/09/2004

Fractional calcium absorption from varying intakes of calcium carbonate co-ingested with wheat bran, as well as alone, was measured in a randomized crossover study in healthy adult women. The calcium carbonate was intrinsically labeled with 45Ca. Absorption from the carbonate, ingested without bran, showed the expected inverse relationship to the logarithm of ingested load size (slope = -0.1199; not substantially different from the value previously reported for milk). At 0.5 mmol calcium load, fractional absorption averaged 0.769 [+ or -] 0.134, whereas at 12.5 mmol load it averaged 0.378 [+ or -] 0.069. in contrast, fractional absorption from calcium carbonate co-ingested with 40 g of a cereal product containing 16 g wheat bran, across a calcium load range from 0.5 to 15.5 mmol, was essentially constant (mean for all loads: 0.230 [+ or -] 0.069). Thus, the calcium-binding capacity of the bran cereal altered the usual inverse relationship between calcium load and fractional absorption. In vitro calcium binding to the bran cereal was linear over a wide range of calcium levels. This suggests that binding of calcium to one or more components of the bran cereal is sufficient to explain the reduced absorption demonstrated in vivo. INDEXING KEY WORDS: humans; bioavailability; wheat bran; calcium carbonate; isotopic labeling techniques

A study of chemical and physiological aspects of enzyme-modified fiber reveals that 10% of total dietary fiber is lost in pea bran and 10% of total dietary fiber is increased in spelt wheat bran due to enzymic modifications. These changes are attributed to the mineral and protein losses. Consumption of modified pea fiber increased the stool weight but no effect on transit time and blood cholesterol was observed.

Because high serum cholesterol is an important, modifiable risk factor for coronary heart disease, factors thought to lower blood cholesterol have been the subject of intense investigation. Dietary fibers, for [...]

Plasma cholesterol concentrations were significantly lower in rats fed a cholesterol-free diet containing white wheat flour than those fed the diet with whole wheat or wheat bran. Concentrations of total bile acids and neutral sterols in cecal digesta were significantly higher in rats fed wheat flour than in those fed whole wheat, wheat pollard or wheat bran. Digesta bile acids and neutral sterol pools correlated negatively with plasma cholesterol, indicating that excretion was regulating plasma concentration. Total cecal volatile fatty acid (VFA) concentrations were unaffected by diet but cecal propionate was higher and butyrate lower in rats fed wheat flour than in those fed whole wheat. Cecal digesta butyrate concentrations correlated negatively with the cholesterol metabolite, coprostanol, and with secondary bile acids. Cecal propionate correlated negatively with plasma cholesterol concentration, but butyrate correlated equally positively, suggesting these VFA were indicators rather than regulators of altered cecal steroid metabolism. Effects of white wheat flour on steroid metabolism and cecal VFA resemble those of oat bran and support the observation that wheat flour might be hypocholesterolemic in humans.

Vol 160, August 14/28, 2000 * Who reports receiving advice to lose weight? Results from a multistate sruvey. C.N. Sciamanna, D.F. Tate, W. Lang, and R.R. Wing. 2334-2339. * Effect [...]

The objective of this study was to analyze the chemical and nutritional composition of two flours obtained from food subproducts (multimixtures): MM 1 based on rice bran and MM2 based [...]