Antioxidant and antiproliferative activities of common vegetables.Chu YF, Sun J, Wu X, Liu RH.
PPMID: 12368383 [PubMed - indexed for MEDLINE]
Arch Tierernahr 2001;55(4):333-50
Effects of rapeseed-press cake glucosinolates and iodine on the performance, the thyroid gland and the liver vitamin A status of pigs.
Schone F, Tischendorf F, Leiterer M, Hartung H, Bargholz J.
Agricultural Institute of Thuringia, Jena, Germany.
Rapeseed press cake (per kg DM 181 g EE, 341 g CP and 23.3 mmol glucosinolates) was tested in a long-term experiment with a total of sixty pigs (live weight range 24 to 104 kg). The 3 x 2 factorial design consisted of three rapeseed press cake levels (no rapeseed press cake--control, 75 g or 150 g rapeseed press cake per kg diet) each with two iodine dosages (125 or 250 micrograms supplementary iodine per kg diet). Reduced feed intake and depressed weight gain were found in groups receiving 150 g rapeseed press cake per kg diet, which correspond to 3.2 mmol glucosinolates per kg diet. At an inclusion level of 75 g rapeseed-press cake per kg diet no differences in feed intake and growth intensity were recorded in comparison to the rape feed free control. The rapeseed-press cake diet increased the weight of thyroid gland and liver and decreased the serum thyroxine (T4) concentration. Higher iodine dosage increased the serum T4 concentration of pigs receiving 75 g rapeseed press cake per kg diet (= 1.6 mmol glucosinolates per kg diet) to the level of the control group and retarded the enlargement of the thyroid gland. Intake of rapeseed products lowered the iodine content of the thyroid gland, however, there was no significant difference between groups given 1.6 and 3.2 mmol glucosinolates per kg diet. The vitamin A content of the whole liver and the vitamin A serum concentration were not influenced by the diets tested. However, rapeseed press cake and the glucosinolates, respectively, decreased the vitamin A concentration per gram liver due to the organ enlargement and the resulting dilution effect.
PMID: 12357593 [PubMed - indexed for MEDLINE]
Nutr Cancer 2002;42(1):1-9
Brassica vegetables and prostate cancer risk: a review of the epidemiological evidence.
Kristal AR, Lampe JW.
Cancer Prevention Research Program, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA. email@example.com
Epidemiological studies have yielded conflicting results on the associations of diet with prostate cancer. We review evidence that Brassica vegetables are associated with reduced prostate cancer risk. Brassica vegetables, which include broccoli, cabbage, mustard and collard greens, and bok choy, contain glucosinolates, the metabolic breakdown products of which are potent modulators of xenobiotic-metabolizing enzymes that protect DNA from damage. Twelve published studies give some information about Brassica vegetables and prostate cancer risk; six of these studies can be clearly interpreted. Of these, three reported statistically significant reduced risks (P < 0.05) and one reported a borderline significant reduced risk (P = 0.06) with high Brassica vegetable consumption. The epidemiological literature provides modest support for the hypothesis that high intakes of Brassica vegetables reduce prostate cancer risk.
PMID: 12235639 [PubMed - in process]
J Agric Food Chem 2002 Sep 11;50(19):5490-5
Antioxidant effects of isorhamnetin 3,7-di-O-beta-D-glucopyranoside isolated from mustard leaf (Brassica juncea) in rats with streptozotocin-induced diabetes.
Yokozawa T, Kim HY, Cho EJ, Choi JS, Chung HY.
Institute of Natural Medicine, Toyama Medical and Pharmaceutical University, Sugitani, Toyama 930-0194, Japan. firstname.lastname@example.org
To investigate the effects of isorhamnetin 3,7-di-O-beta-D-glucopyranoside (isorhamnetin diglucoside), a major flavonoid compound of mustard leaf, on oxidative stress due to diabetes mellitus, in vivo and in vitro studies were carried out. Oral administration of isorhamnetin diglucoside (10 or 20 mg/kg of body weight/day for 10 days) to rats with streptozotocin-induced diabetes significantly reduced serum levels of glucose and 5-(hydroxymethyl)furfural (5-HMF), which is glycosylated with hemoglobin and is an indicator of oxidative stress. After intraperitoneal administration, isorhamnetin diglucoside did not show these activities. In addition, after oral administration, the thiobarbituric acid-reactive substance levels of serum, and liver and kidney mitochondria declined significantly compared with the control group in a dose-dependent manner, whereas after intraperitoneal administration these levels fell only slightly. On the basis of the oral and intraperitoneal results, it was hypothesized that isorhamnetin diglucoside was converted to its metabolite in vivo, and its conversion to its aglycone, isorhamnetin, by beta-glucosidase was confirmed; isorhamnetin acted as an antioxidant. Moreover, it was observed that isorhamnetin diglucoside had no effect on the 1,1-diphenyl-2-picrylhydrazyl radical, whereas isorhamnetin showed a potent antioxidant effect in vitro. In addition, intraperitoneal administration of isorhamnetin reduced serum glucose and 5-HMF levels. Furthermore, lipid peroxidation in blood, liver, and kidney associated with diabetes mellitus declined after the administration of isorhamnetin. These results suggest that isorhamnetin diglucoside is metabolized in vivo by intestinal bacteria to isorhamnetin and that isorhamnetin plays an important role as an antioxidant.
PMID: 12207497 [PubMed - indexed for MEDLINE]
Indian J Med Res 1995 Nov;102:223-6
Role of goitrogens in iodine deficiency disorders & brain development.
Rao PS, Lakshmy R.
National Institute of Nutrition, Hyderabad.
Although iodine deficiency has primarily been implicated in the causation of goitre, the significant role played by food goitrogens in the etiology of iodine deficiency disorder (IDD) is being increasingly recognized. Impaired brain development is the major cause of concern in IDD. Detailed experimental studies were undertaken to ascertain various biochemical changes associated with developing brain in response to treatment with a goitrogens--thiocyanate. Addition of thiocyanate to food deprived of KI brought down significantly the circulating levels of thyroxine (T4) in rats. Nucleic acids and protein content in different regions of brain were significantly lowered in rat pups exposed to thiocyanate. The rate of microtubule assembly, which is detrimental for neurite growth was considerably lowered, thereby influencing both myelin deposition and synaptogenesis in developing brain. Goitrogen intake not only caused an adaptive increase in the activity of type II 5'-deiodinase, which governs availability of triiodothyronine (T3) in brain, it also increased the latter's binding to brain nuclear receptors under conditions of thiocyanate induced hypothyroid state. Addition of adequate quantities of KI mitigated thiocyanate induced alterations by restoring circulating level of thyroxine. These investigations suggest that goitrogens play a significant role in influencing biochemical events unique to developing brain.
PPMID: 8675242 [PubMed - indexed for MEDLINE]
Horm Metab Res 1995 Oct;27(10):450-4
Iodine metabolism in response to goitrogen induced altered thyroid status under conditions of moderate and high intake of iodine.
Lakshmy R, Rao PS, Sesikeran B, Suryaprakash P.
National Institute of Nutrition, Indian Council of Medical Research, Hyderabad, India.
Metabolic experiments in rats were undertaken to relate excretory pattern of iodine and thiocyanate, with thyroid weight and the circulating levels of thyroxine, in response to moderate and high intake of iodine and under conditions of goitrogen induced altered thyroid status. On a moderate intake of iodine (by depriving diet of KI) 25 mg of thiocyanate or substitution of 1/3rd proportion of casein based diet with dry cabbage, could significantly reduce plasma thyroxine level by 60 days. Neither body weight nor the weights of liver, kidney, heart or spleen were affected due to exposure to goitrogens. A significant increase in thyroid weight as well as higher excretion of iodine and thiocyanate were evident in goitrogen-fed rats. Presence of high amounts of KI, to a certain extent, offered protection from adverse effects of the goitrogens. Semi quantitative assessment of thyroid, indicated hypofunctioning of thyroid with follicular hyperplasia in thiocyanate fed rats. These alterations were of moderate degree in response to cabbage feeding. These results emphasize that, moderate intake of iodine, adequate to meet iodine requirement, may not ensure normal functioning of thyroid in the presence of goitrogens.
PMID: 8575723 [PubMed - indexed for MEDLINE]
Gen Comp Endocrinol 1992 Jan;85(1):147-55
Measurement of plasma thyroxine binding protein in relation to thyroidal condition in the turtle, Trachemys scripta, by radioimmunoassay.
Pavgi S, Licht P.
Department of Integrative Biology, University of California, Berkeley 94720.
Polyclonal (rabbit) antisera were generated against a high-affinity plasma thyroxine (T4) binding protein (TBP) purified from the turtle, Trachemys scripta, and used to develop a specific radioimmunoassay (RIA). The RIA demonstrated the presence of an immunochemically related protein in the plasma of several other species of Trachemys and in members of several other genera from the same family, Emydidae. Plasma from all nonemydids and some emydid genera either showed no competition or nonparallelism in RIA. The presence and level of radioimmunoassayable TBP in diverse species correlated with results of previous comparative measurements of T4 binding activity. However, an immunoreactive protein of the same molecular weight as TBP was identified in all turtles by Western blot analysis. More detailed studies in T. scripta demonstrated that variations in plasma T4 binding activity induced by experimental or environmental manipulations were related to differences in TBP concentrations. The concentration of TBP varied by orders of magnitude (from less than 1 to ca. 150 mg/liter) in euthyroid animals; levels showed ontogenetic changes (virtually absent in hatchlings) and were directly related to thyroidal status. Experimentally induced hypothyroidism (goitrogen treatment or surgical thyroidectomy) resulted in a marked suppression of TBP, and T4 treatment prevented its decline or reinstated it. Thus, in the turtle, this T4 transport protein may exist in higher concentrations and its levels are more variable and show a different relationship to thyroid activity than the analogous T4 binding globulin (TBG) in mammals.
PMID: 1563614 [PubMed - indexed for MEDLINE]