Type IV resistant starch increases cecum short chain fatty acids level in rats.

Resistant starches are type of dietary fibers. However, their physiological effects depend on the way they resist digestion in the gastrointestinal tract. The objective of this study was to examine the hypothesis that new type of RS4 preparations, of in vitro digestibility of about 50%, obtained by cross-linking and acetylation, acts as a prebiotic by increasing short chain fatty acids content in cecum digesta. The rats were fed with diet containing pregelatinized, cross-linked and acetylated starches as a main carbohydrate source. Pregelatinized, but not chemically modified, potato starch was used in the composition of the control diet. After two weeks of experiment the increase of short chain fatty acids contents in ceceum digesta was observed. The intake of starch A, cross-linked only with adipic acid, resulted in increase of about 40% of short chain fatty acids content, whereas starch PA cross-linked with sodium trimetaphosphate and adipic acid of about 50%. The utmost twofold increase was observed in the case of the production of propionic acid. In contrast, the content of butyric acid increased (12%) only as an effect of consumption of starch PA and even decreased (about 30%) in case of starch A. Both RS4 starches caused an increase of the production of acetic acid by more than 40%. No changes in serum biochemistry, liver cholesterol and organ weights of rats were stated.

Food preferences of girls and nutritional value of diets and their effect on organisms of rats in terms of risk of obesity and atherosclerosis.

The study was conducted on 28 growing female Wistar rats, fed ad libitum for 84 days with four different diets: preferred poor, preferred rich, recommended and Labofeed B. The diet intake, feed efficiency, weight/length ratio, serum TG, TC and HDL-C levels were determined. Results were verified statistically using one-way ANOVA and the Scheffe test. The poor preferred diet with predominating fruit and vegetables, in comparison to the rich preferred diet, containing sweets, lowered the risk of obesity and atherosclerosis. The recommended diet, based on the model food ration for girls aged 13-15 years, lowered the risk of these diseases too.

Nutraceutical inhibitors of urokinase: potential applications in prostate cancer prevention and treatment.

Epidemiological studies have shown that the clinical incidence of prostate cancer varies by geographical area. When individuals move from low to high prostate cancer incidence areas, the risk of developing cancer increases to the level observed in the indigenous population. It was hypothesized that this observation is related to diet or more specifically to nutraceuticals present in food, medicinal plants, and herbs. Nutraceuticals can inhibit or downregulate enzymes critical for cancer formation. We tested this hypothesis by searching the 3D database of nutraceuticals and docking them to the 3D structure of urokinase. In addition to nutraceuticals, the data-base contains known uPA inhibitors that served as positive controls. From >1,000 compounds, several potential uPA inhibitors have been selected (antipain, leupeptin, folic acid, rosmarinic acid, lavendustin A, fisetin, myricetin, tolfenamic acid). Some of these were subject to further tests on inhibitory activity and inhibition of sprout formation. We found that compounds selected by computational methods indeed inhibit uPA and sprout formation. However, because the database of nutraceuticals was small, we did not expect to find either many or high affinity/specific inhibitors. Rather, we tested this method as a proof of concept. All the facts described above support the hypothesis that nutrients selected by computerized searches can inhibit unwanted uPA activity and thus reduce angiogenesis. If true, a proper diet rich in uPA-inhibiting nutraceuticals might support the prevention of prostrate cancer and be a supportive tool in prostate cancer treatment.

Spatial distribution of liposome encapsulated tin etiopurpurin dichloride (SnET2) in the canine prostate: implications for computer simulation of photodynamic therapy.

Photodynamic therapy (PDT) is a minimally invasive treatment that can be employed in many human diseases including prostate cancer. PDT for prostate cancer depends on the sequestration of a photosensitizing drug within the glandular tissue. The photosensitizer is subsequently activated by light (usually from a laser) and the active drug destroys tissue. Since prostate cancer is a multifocal disease, PDT must ablate the glandular prostate completely. This will depend on the precise placement of light sources in the prostate and delivery of a therapeutic light dose to the entire gland. Also, sources of light and their spatial distribution must be tailored to each individual patient. The uniform, therapeutic light distribution can be achieved by interstitial light irradiation. In this case, the light is delivered by diffusers placed within the substance of the prostate parallel to the urethra at a distance optimized to deliver adequate levels of light and to create the desired photodynamic effect. To help achieve the uniform light distribution throughout the prostate we have developed a computer program that can determine treatment effects. The program predicts the best set of parameters and the position of light diffusers in space, and displays them in graphical or in numerical form assuming a fixed attenuation coefficient. The two parameters of greatest importance in the computer simulation are attenuation coefficient and critical fluence. Both depend on the concentration of active drug within the prostate gland. It is necessary to know the nature of the spatial distribution of photosensitizer within the prostate to execute computer modeling of PDT with high precision. We found that the concentration of SnET2 is heterogeneous in nature, and is higher in the proximity of the glandular capsule. It is clear therefore that any future attempts of computerized modeling of this procedure must take into consideration the uneven sequestration of photosensitizer and the consequential asymmetrical necrosis of the prostate.