92 research outputs found
Biosynthesis and Accumulation of Sulphur Compounds in White Radish During the First Three Days of Sprouting
 Glucosinolates (GLs) and S-methyl cysteine sulfoxide (SMCSO) are natural sulphur containing phytochemicals. They are two of the most important bioactive compounds found in brassica vegetables, which are highly regarded for their health-promoting activity. In this study we have analysed the content of GLs and SMCSO in white radish, by an HPLC-MS method, in order to illustrate their biosynthesis and accumulation during the first 72 hours of sprouting. Total GLs content ranged between 54.17 and 126.86 µmol/g DW. There were eight GLs identified, in radish sprouts and around 94 % of them were aliphatic. Obvious differences, during the 72 hours of sprouting, were noticed in glucoraphenin and glucoraphasatin. S-methyl cysteine sulfoxide content ranged between 0.21 and 35.95 µmol/g DW. Our results revealed a negative strong correlation between GLs and SMCSO
The dietary isothiocyanate sulforaphane modulates gene expression and alternative gene splicing in a PTEN null preclinical murine model of prostate cancer
<p>Abstract</p> <p>Background</p> <p>Dietary or therapeutic interventions to counteract the loss of PTEN expression could contribute to the prevention of prostate carcinogenesis or reduce the rate of cancer progression. In this study, we investigate the interaction between sulforaphane, a dietary isothiocyanate derived from broccoli, PTEN expression and gene expression in pre malignant prostate tissue.</p> <p>Results</p> <p>We initially describe heterogeneity in expression of PTEN in non-malignant prostate tissue of men deemed to be at risk of prostate cancer. We subsequently use the mouse prostate-specific PTEN deletion model, to show that sulforaphane suppresses transcriptional changes induced by PTEN deletion and induces additional changes in gene expression associated with cell cycle arrest and apoptosis in PTEN null tissue, but has no effect on transcription in wild type tissue. Comparative analyses of changes in gene expression in mouse and human prostate tissue indicate that similar changes can be induced in humans with a broccoli-rich diet. Global analyses of exon expression demonstrated that sulforaphane interacts with PTEN deletion to modulate alternative gene splicing, illustrated through a more detailed analysis of DMBT1 splicing.</p> <p>Conclusion</p> <p>To our knowledge, this is the first report of how diet may perturb changes in transcription induced by PTEN deletion, and the effects of diet on global patterns of alternative gene splicing. The study exemplifies the complex interaction between diet, genotype and gene expression, and the multiple modes of action of small bioactive dietary components.</p
Effect of Sulforaphane on NOD2 via NF-κB: implications for Crohn’s disease
BACKGROUND: Sulforaphane has well established anti-cancer properties and more recently anti-inflammatory properties have also been determined. Sulforaphane has been shown to inhibit PRR-mediated pro-inflammatory signalling by either directly targeting the receptor or their downstream signalling molecules such as the transcription factor, NF-κB. These results raise the possibility that PRR-mediated inflammation could be suppressed by specific dietary bioactives. We examined whether sulforaphane could suppress NF-κB via the NOD2 pathway. METHODS: Human embryonic kidney 293T (HEK293T) cells were stably transfected with NOD2 variants and the NF-κB reporter, pNifty2-SEAP. The cells were co-treated with sulforaphane and MDP and secreted alkaline phosphatase (SEAP) production was determined. RESULTS: We found that sulforaphane was able to significantly suppress the ligand-induced NF-κB activity at physiologically relevant concentrations, achievable via the consumption of broccoli within the diet. CONCLUSIONS: These results demonstrate that the anti-inflammatory role of sulforaphane is not restricted to LPS-induced inflammatory signalling. These data add to the growing evidence that PRR activation can be inhibited by specific phytochemicals and thus suggests that diet could be a way of controlling inflammation. This is particularly important for a disease like Crohn’s disease where diet can play a key role in relieving or exacerbating symptoms
Genetic regulation of glucoraphanin accumulation in Beneforté® broccoli
Diets rich in broccoli (Brassica oleracea var italica) have been associated with maintenance of cardiovascular health and reduction in risk of cancer. These health benefits have been
attributed to glucoraphanin that specifically accumulates in broccoli. The development of broccoli with enhanced concentrations of glucoraphanin may deliver greater health benefits.
Three high-glucoraphanin F1 broccoli hybrids were developed in independent programmes through genome introgression from the wild species Brassica villosa. Glucoraphanin and other metabolites were quantified in experimental field trials. Global SNP analyses quantified the differential extent of B. villosa introgression
The high-glucoraphanin broccoli hybrids contained 2.5–3 times the glucoraphanin content of standard hybrids due to enhanced sulphate assimilation and modifications in sulphur partitioning between sulphur-containing metabolites. All of the high-glucoraphanin hybrids possessed an introgressed B. villosa segment which contained a B. villosa Myb28 allele. Myb28
expression was increased in all of the high-glucoraphanin hybrids. Two high-glucoraphanin hybrids have been commercialised as Beneforte broccoli.
The study illustrates the translation of research on glucosinolate genetics from Arabidopsis to broccoli, the use of wild Brassica species to develop cultivars with potential consumer benefits, and the development of cultivars with contrasting concentrations of glucoraphanin for use in blinded human intervention studie
Accumulation of Dietary S-Methyl Cysteine Sulfoxide in Human Prostate Tissue
Scope: Observational studies have associated consumption of cruciferous vegetables with reduced risk of prostate cancer. This effect has been associated with the degradation products of glucosinolates—thioglycosides that accumulate within crucifers. The possible role of S-methyl cysteine sulfoxide, a metabolite that also accumulates in cruciferous vegetables, and its derivatives, in cancer prevention is relatively unexplored compared to glucosinolate derivatives. The hypothesis that consuming a broccoli soup results in the accumulation of sulfate (a SMCSO derivative) and other broccoli-derived metabolites in prostate tissue is tested. Methods and results: Eighteen men scheduled for transperineal prostate biopsy were recruited into a 4-week parallel single blinded diet supplementation study (NCT02821728). Nine men supplemented their diet with three 300 mL portions of a broccoli soup each week for four weeks prior to surgery. Analyses of prostate biopsy tissues reveal no detectable levels of glucosinolates and derivatives. In contrast, SMCSO is detected in prostate tissues of the participants, with significantly higher levels in tissue of men in the supplementation arm. SMCSO was also found in blood and urine samples from a previous intervention study with the identical broccoli soup. Conclusion: The consequences of SMCSO accumulation in prostate tissues and its potential role in prevention of prostate cancer remains to be investigated
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Diet rich in high glucoraphanin broccoli reduces plasma LDL cholesterol: evidence from randomised controlled trials
Cruciferous-rich diets have been associated with reduction in plasma LDL-cholesterol (LDL-C), which may be due to the action of isothiocyanates derived from glucosinolates that accumulate in these vegetables. This study tests the hypothesis that a diet rich in high glucoraphanin (HG) broccoli will reduce plasma LDL-C.
METHODS AND RESULTS:
One hundred and thirty volunteers were recruited to two independent double-blind, randomly allocated parallel dietary intervention studies, and were assigned to consume either 400 g standard broccoli or 400 g HG broccoli per week for 12 weeks. Plasma lipids were quantified before and after the intervention. In study 1 (37 volunteers), the HG broccoli diet reduced plasma LDL-C by 7.1% (95% CI: -1.8%, -12.3%, p = 0.011), whereas standard broccoli reduced LDL-C by 1.8% (95% CI +3.9%, -7.5%, ns). In study 2 (93 volunteers), the HG broccoli diet resulted in a reduction of 5.1% (95% CI: -2.1%, -8.1%, p = 0.001), whereas standard broccoli reduced LDL-C by 2.5% (95% CI: +0.8%, -5.7%, ns). When data from the two studies were combined the reduction in LDL-C by the HG broccoli was significantly greater than standard broccoli (p = 0.031).
CONCLUSION:
Evidence from two independent human studies indicates that consumption of high glucoraphanin broccoli significantly reduces plasma LDL-
Hypoxia-inducible factor-1 (HIF-1) pathway activation by quercetin in human lens epithelial cells
Quercetin is a dietary bioflavonoid which has been shown to inhibit lens opacification in a number of models of cataract. The objectives of this study were to determine gene expression changes in human lens epithelial cells in response to quercetin and to investigate in detail the mechanisms underlying the responses. FHL-124 cells were treated with quercetin (10 µM) and changes in gene expression were measured by microarray. It was found that 65% of the genes with increased expression were regulated by the hypoxia-inducible factor-1 (HIF-1) pathway. Quercetin (10 and 30 µM) induced a time-dependent increase in HIF-1a protein levels. Quercetin (30 µM) was also responsible for a rapid and long-lasting translocation of HIF-1a from the cytoplasm to the nucleus. Activation of HIF-1 signaling by quercetin was confirmed by qRT–PCR which showed upregulation of the HIF-1 regulated genes EPO, VEGF, PGK1 and BNIP3. Analysis of medium taken from FHL-124 cells showed a sustained dose-dependent increase in VEGF secretion following quercetin treatment. The quercetin-induced increase and nuclear translocation of HIF-1a was reversed by addition of excess iron (100 µM). These results demonstrate that quercetin activates the HIF-1 signaling pathway in human lens epithelial cells
A randomised controlled crossover trial investigating the short-term effects of different types of vegetables on vascular and metabolic function in middle-aged and older adults with mildly elevated blood pressure: the VEgetableS for vaScular hEaLth (VESSEL) study protocol
A diet rich in fruits and vegetables is recommended for cardiovascular health. However, the majority of Australians do not consume the recommended number of vegetable servings each day. Furthermore, intakes of vegetables considered to have the greatest cardiovascular benefit are often very low. Results from prospective observational studies indicate that a higher consumption of cruciferous vegetables (e.g. broccoli, cabbage, cauliflower) is associated with lower cardiovascular disease risk. This may be due to the presence of specific nutrients and bioactive compounds found almost exclusively, or at relatively high levels, in cruciferous vegetables. Therefore, the aim of this randomised controlled crossover trial is to determine whether regular consumption of cruciferous vegetables results in short-term improvement in measures related to cardiovascular disease risk, including ambulatory blood pressure, arterial stiffness, glycaemic control, and circulating biomarkers of oxidative stress and inflammation
Transcriptional changes in prostate of men on active surveillance after a 12-mo glucoraphanin-rich broccoli intervention—results from the Effect of Sulforaphane on prostate CAncer PrEvention (ESCAPE) randomized controlled trial
Background Epidemiological evidence suggests that consumption of cruciferous vegetables is associated with reduced risk of prostate cancer progression, largely attributed to the biological activity of glucosinolate degradation products, such as sulforaphane derived from glucoraphanin. Because there are few therapeutic interventions for men on active surveillance for prostate cancer to reduce the risk of cancer progression, dietary approaches are an appealing option for patients. Objective We evaluated whether consumption of a glucoraphanin-rich broccoli soup for 1 y leads to changes in gene expression in prostate tissue of men with localized prostate cancer. Methods Forty-nine men on active surveillance completed a 3-arm parallel randomized double-blinded intervention study for 12 mo and underwent transperineal template biopsy procedures and dietary assessment at the start and end of the study. Patients received a weekly 300 mL portion of soup made from a standard broccoli (control) or from 1 of 2 experimental broccoli genotypes with enhanced concentrations of glucoraphanin, delivering 3 and 7 times that of the control, respectively. Gene expression in tissues from each patient obtained before and after the dietary intervention was quantified by RNA sequencing followed by gene set enrichment analyses. Results In the control arm, there were several hundred changes in gene expression in nonneoplastic tissue during the 12 mo. These were associated with an increase in expression of potentially oncogenic pathways including inflammation processes and epithelial–mesenchymal transition. Changes in gene expression and associated oncogenic pathways were attenuated in men on the glucoraphanin-rich broccoli soup in a dose-dependent manner. Although the study was not powered to assess clinical progression, an inverse association between consumption of cruciferous vegetables and cancer progression was observed. Conclusion Consuming glucoraphanin-rich broccoli soup affected gene expression in the prostate of men on active surveillance, consistent with a reduction in the risk of cancer progression. This trial was registered at clinicaltrials.gov as NCT01950143
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Identifying ancient water availability through phytolith analysis: An experimental approach.
Water management was critical to the development of complex societies but such systems are often difficult, if not impossible, to recognise in the archaeological record, particularly in prehistoric communities when water management began. This is because early irrigation systems are likely to have been ephemeral and as such would no longer be visible in the archaeological record. We conducted a three year crop growing experiment in Jordan to test the hypothesis that phytoliths (opaline silica bodies formed in plants) can be used to detect the level of past water availability and hence be used as a source of information for inferring past water management. Over a three year period we grew native land races of six-row barley (Hordeum vulgare) and durum wheat (Triticum durum) at three crop growing stations in Jordan with the crops being subjected to different irrigation regimes. Seeds were sown in the autumn and the crops harvested in the spring. The plants were then exported to the University of Reading for phytolith processing. Our results show that while there were unknown factors that influenced phytolith production between years, at the higher levels, the ratio of ‘fixed’ form phytoliths (those formed as a result of genetically determined Silicon uptake) to ‘sensitive’ form phytoliths (those whose Silicon uptake is environmentally controlled) can be used to assess past water availability. Our study is the first large scale experimental project to test this method and take into account multiple variables that can affect phytolith production such as soil composition and chemistry, location, climate and evapotranspiration rates. Results from the cereals grown at two of the crop growing stations, Deir ‘Alla and Ramtha, which received between 100 millimetres and 250 millimetres rainfall per annum, demonstrate that if the ratio of fixed to sensitive phytolith forms is >1, the level of past water availability can be predicted with 80% confidence. Results from the crops grown at the other growing station, Kherbet as-Samra, which received less than 100 millimetres of rainfall per year show that if the ratio of fixed to sensitive forms is >0.5, the level of past water availability can be predicted with 99% confidence. This demonstrates that phytolith analysis can be used as a method to identify past water availability
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