1,721,008 research outputs found
Anti-cancer properties of olive oil secoiridoid phenols: a systematic review of in vivo studies.
Epidemiological studies suggest that olive oil intake is associated to a reduced risk of cancer. Recently, the chemopreventive activity of olive oil has been attributed to its unique phenolic compounds represented by phenolic alcohols, hydroxytyrosol (3,4-dihydroxyphenylethanol: 3,4-DHPEA) and tyrosol (p-hydroxyphenylethanol: p-HPEA), and their secoiridoid derivatives 3,4-DHPEA-EA (oleuropein aglycon), p-HPEA-EA (ligstroside aglycon), 3,4-DHPEA-EDA, p-HPEA-EDA (oleocanthal), and oleuropein. Several studies have demonstrated that these compounds are able to inhibit proliferation and induce apoptosis in different tumor cell lines. These in vitro effects have been recently summarized in several reviews. The aim of this systematic review was to evaluate the in vivo anti-cancer activities of secoiridoid phenols as evidenced by either animal models of carcinogenesis or human intervention trials. From the literature research through "PubMed" and "Web of Science", 16 animal studies and 5 human intervention trials were identified and included in the review. Most of the animal studies have confirmed the ability of these compounds to inhibit the carcinogenesis process at both initiation and promotion/progression phases. All human intervention trials have investigated the effects of olive oil phenols on DNA damage. Among the five selected studies, three have shown a significant preventive effect on oxidative DNA damage in terms of reduction of 8-oxo-7,8-dihydro-2'-deoxyguanosine in urine, in mitochondria DNA of mononuclear cells and in lymphocyte DNA. The other two studies failed to see an effect on the urinary excretion of either etheno-DNA adducts or oxidation products of guanine. Further investigations are necessary to clarify the real chemopreventive potential of olive oil secoiridoid phenols on humans performing intervention studies on populations at high cancer ris
Abundance of guanine, guanosine, inosine and adenosine in human seminal plasma
Guanine, guanosine, inosine and adenosine were found in large amounts in seminal plasma from 145 men, regardless of whether spermatozoa were present or not. The mean guanine level in 61 normozoospermic men was 89.7 +/- 93.1 mumol/l; this was significantly lower in 32 vasectomized men (18.9 +/- 31 mumol/l) suggesting the involvement of the epididymis in its secretion. Guanine and nucleoside levels were significantly higher in the seminal plasma of oligozoo- and azoospermic than normozoospermic men. Guanine and nucleoside levels were consistently inter-related in the seminal plasma of normozoospermic men with the best correlation between guanine and guanosin
Association of some hydrolytic enzymes with the prostasome membrane and their differential responses to detergent and PIPLC treatment
Prostasomes are human prostate derived organelles that were isolated from both prostatic fluid and seminal plasma for the present study. Specific activities were determined for prostasome membrane-associated enzymes, alkaline phosphatase (ALP), 5'-nucleotidase (5'NT), and alkaline phosphodiesterase I (APD). The mode of their membranous anchoring was studied by treatment of prostasomes with phosphoinositol-specific phospholipase C (PIPLC) and different detergents. A substantial amount of ALP (50%) and 5'NT (31%) was released by incubation of prostasomes with 2 U/ml of PIPLC contrary to the small amount of APD (12%) released by the same treatment. After PIPLC treatment, the enzymes were recovered in the aqueous phase after phase repartition in Triton X-114 indicating that PIPLC removed the hydrophobic domain converting the enzymes from membrane-linked to aqueous soluble forms. Octyl glycoside was the most efficient one among different detergents to solubilize the enzymes from the prostasome membrane. Both ALP and 5'NT were resistant to the treatment with Triton X-100 and Triton X-114. These results suggest that ALP, 5'NT, and APD are more or less extensively linked to the prostasome membrane via a glycophosphoinositide anchor
The Role of Diet in Osteoporotic Fracture Risk
Introduction: Osteoporosis-related fractures constitute a considerable public health burden and nutrition is an important modifiable factor influencing bone health. Numerous micronutrients, macronutrients, and dietary components influence bone health, as well as dietary pattern. This short review describes the role of diet on osteoporosis fracture risk, investigating those dietary factors which improve bone health.
Materials and Methods: Searching Pubmed and Web of Science, we performed a review of current literature.
Results: This review reported the beneficial effects of micronutrients (e.g. calcium, vitamin D, potassium, magnesium, vitamin K, and vitamin B12), macronutrients (e.g. protein and carbohydrates), and foods (e.g. fish and seafood, fruits and vegetables) on osteoporotic fracture risk. A healthy diet, such as the Mediterranean diet, is important for decreasing osteoporotic fracture risk. A potential benefit on fracture risk is attributed to the “Healthy” and “Milk/dairy” dietary patterns which emphasise the intake of fruit, vegetables, whole grains, poultry and fish, nuts and legumes, and low-fat dairy products. By contrast, the unhealthy “Meat/Western” dietary pattern, characterised by high consumption of soft drinks, fried foods, meat and processed products, sweets and desserts, and refined grains, increased osteoporosis fracture risk.
Conclusions: Diet play an important role in bone health. A healthy diet prevents osteoporosis and reduces osteoporotic fracture risk
Effetto di alcuni metaboliti del benzene sull'induzione di enzimi di fase 2: GST e DTD. 41° congresso Nazionale della Società Italiana di Igiene, Medicina Preventiva e Sanità Pubblica
Pinoresinol inhibits proliferation and induces differentiation on human HL60 leukemia cells
Pinoresinol (PIN), one of the simplest lignans, is the precursor of other dietary lignans that are present in whole-grain cereals, legumes, fruits, and other vegetables. Several experimental and epidemiological evidences suggest that lignans may prevent human cancer in different organs. In this study we investigated the chemopreventive properties of PIN on cell lines derived from different sites either expressing or not the functional tumor suppressor protein p53. It was found that PIN inhibited the proliferation of p53 wild type colon and prostate tumor cells (HCT116 and LNCaP) while in breast cells the inhibition of growth was observed only in p53 mutant cells (MDA-MB-231). A potent antiproliferative activity of PIN was also observed on p53 null cells HL60 (IC50% 8 μM), their multidrug resistant variant HL60R (IC50% 32 μM) and K562. On HL60 cells, PIN caused a block of cell cycle in the G0/G1 phase, induced a weak proapoptotic effect but it was a good trigger of differentiation (NBT reduction and CD11b expression). PIN caused an upregulation of the CDK inhibitor p21(WAF1/Cip1) both at mRNA and protein levels so suggesting that this could be a mechanism by which PIN reduced proliferation and induced differentiation on HL60 cells
Arachidonic acid 15-lipoxygenase and traces of E prostaglandins in purified human prostasomes
Human spermatozoa are associated with arachidonate 15-lipoxygenase activity. This activity could be due to 15-lipoxygenase in small organelles (prostasomes), which are known to bind hydrophobically to germ cells. This possibility was assessed by separating prostasomes from human spermatozoa by differential centrifugation and purifying them by gel filtration (Sephadex G-200). Purified prostasomes metabolized [1-14C]arachidonic acid to 15(S)-hydroxyeicosatetraenoic acid as determined by reverse phase and by chiral phase HPLC and by gas chromatography-mass spectrometry. Biosynthesis of prostaglandins could not be detected, but the prostasomes contained trace amounts of the four major E prostaglandins of human seminal fluid (3.6 nmol mg-1 of prostasomal protein). Arachidonic acid 15-lipoxygenase has recently been implicated in the acrosome reaction of bull spermatozoa and it may have a similar function in the acrosome reaction of human spermatozoa
Postmenopausal exogenous hormone therapy and Melanoma risk in women: A systematic review and time-response meta-analysis
In vitro chemo-preventive activities of hydroxytyrosol: the main phenolic compound present in extra-virgin olive oil.
The co-incubation in the culture medium with hydroxytyrosol [3,4-dihydroxyphenyl ethanol (3,4-DHPEA)], the main phenolic compound present in extra-virgin olive oil, and H2O2 reduces the oxidative DNA damage in peripheral blood mononuclear cells (PBMC). In this study we investigate, by the comet assay, the ability of 3,4-DHPEA to inhibit the H2O2 induced DNA damage when pre-incubated with PBMC and then removed before the exposure of cells to H2O2. Low doses of 3,4-DHPEA (10–100 μM) pre-incubated for 30 min with PBMC reduced the DNA damage induced by the treatment with H2O2 200 μM for 5 min at 4 °C. Prolonging the exposure time up to 6 h completely prevented the DNA damage. Furthermore we extensively analysed, by the MTT assay, the anti-proliferative activities of 3,4-DHPEA on breast (MDA and MCF-7), prostate (LNCap and PC3) and colon (SW480 and HCT116) cancer cell lines and correlated these effects with the H2O2 accumulation. The concentration of H2O2 in the culture medium was measured by the ferrous ion oxidation–xylenol orange method. The proliferation of all the cell lines was inhibited but at different levels: the prostate cancer cells were more resistant to the growth inhibition with respect to breast and colon cancer cells. The ability of the different cell lines to remove H2O2 from the culture medium was inversely correlated with their sensitivity to the anti-proliferative effect of 3,4-DHPEA. Therefore, 3,4-DHPEA may act as a chemopreventive agent acting on both initiation and promotion/progression phases of carcinogenesis
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