补充β-胡萝卜素对青年人群红细胞溶血度及淋巴细胞增殖活性影响的研究

目的探讨补充不同剂量β-胡萝卜素(β-C)对青年健康人群外周血淋巴细胞增殖活性和红细胞溶血度的影响。方法19～23岁青年188名(男95、女93)。随机分为四组,对照组仅给维生素E(VE)5mg/d,其余3组分别给予β-C16.7mg/d、8.35mg/d和5.57mg/d,干预时间为8w。补充前后分别获取各组研究对象外周血红细胞和淋巴细胞,检测红细胞溶血度及淋巴细胞增殖活性。结果干预后,补充β-C素16.7mg组淋巴细胞增殖活性较干预前平均升高了30.4%(P<0.05);与对照组相比平均升高了25.0%(P<0.05)。补充8.35mg/d组与干预前相比,红细胞的溶血度明显降低(P<0.05),而16.7mg/d补充组干预前、后红细胞溶血度却未见有明显差异(P>0.05)。结论补充不同剂量β-C可能产生不同的细胞功能效应,较高剂量可提高青年机体淋巴细胞增殖活性,而相对较低剂量能增强红细胞抗脂质过氧化的能力,降低红细胞溶血度。     

Bioscreening of Australian olive mill waste extracts: biophenol content, antioxidant, antimicrobial and molluscicidal activities.

The biophenolic fraction was characterized in olive mill waste (OMW) obtained as a by-product from processing of Mission and Frantoio olive fruit. OMW produced from the Mission fruit contained higher total phenol content. Individual biophenols with the exception of verbascoside and a hydroxytyrosol-secoiridoid were also present at higher concentrations in the OMW produced from Mission cultivar. Antioxidant activities were measured in aqueous (DPPH) and emulsion (BCBT) systems. The Frantoio extract was more active than the Mission extract in the DPPH assay - EC(50) values were 28.3+/-1.7 ppm and 34.7+/-1.7 ppm, respectively. Activities were reversed in the BCBT, with the Mission extract (EC(50) 60.6+/-2.3 ppm) more potent than the Frantoio extract (EC(50) 79.9+/-2.0 ppm), and this may be related to the more lipophilic nature of the Mission extract. Both extracts showed broad spectrum antibacterial activity against Staphylococcus aureus, Bacillus subtilis, Escherichia coli and Pseudomonas aeruginosa; whereas individual biophenols (hydroxytyrosol, luteolin, oleuropein) showed more limited activity. Molluscicidal activity was measured against Isidorella newcombi and LD(50) values were 424 ppm and 541 ppm for Mission and Frantoio extracts, respectively. The results suggest that OMW may be utilised as a source of bioactive compounds.     

Research on serum levels of retinol, α-tocopherol β-carotene,and 12 elements in gastric dysplasia and gastric cancer patients

Serum levers of retinol, α-tocopherol, β-carotene and elements (Zn, Cu, Mn, Ca, Mg, Cr, Co, Cd, Mo, Se) were determined in 45 gastric cancer and 41 gastric dysplasia patients, and 48 normal subjects. The results showed that β-carotene and Se, Co were lower in gastric cancer patients than that in gastric dysplasia patients or in normal subjects, Ni and Cr levels were lower and Mn, Ca and Cd were higher in gastric cancer than in dysplasia patients. Zn, Fe, Cr, Cd were lower and Mn, Ca, Mg, Mo levels were higher in gastric cancer patients than in normal. The differences mentioned are statistically significant. The stepwise discriminant analysis of 10 variables (Mn, Fe, Ca, Cr, Mo, Co, Cd, Se, α-tocophrol, β-carotene) were used in identifying gastric cancer, with 100% of the positive rate. The potential protective effect of β-carotene and Se against gastric cancer is an interesting postulate. We suggest that optimum supplement of β-carotene and Se might will be beneficial to gastric dysplasia patients in preventing the development of gastric cancer.     

Effects of β-carotene and aspartame on clustogenic activity of cyclophosphamide and dioxidine in mice

Antimutagenic effects of combination of aspartame (0.4 and 4 mg/kg) and -carotene (0.15-15 mg/kg) were studied by estimation of chromosome aberrations in bone marrow cells of C57Bl/6 mice. Single and 5-day treatment with this combination decreased the clastogenic effects of dioxidine and cyclophosphamide and produced a more potent and universal antimutagenic effect than its constituents.     

The CARET asbestos-exposed cohort: Baseline characteristics and comparison to other asbestos-exposed cohorts

The Carotene and Retinol Efficacy Trial (CARET) was a double-blind, placebo-controlled trial of the daily administration of 25,000 IU vitamin A and 30 mg β-carotene for the prevention of lung cancer. Of close to 18,500 participants, more than 4,000 were asbestos-exposed men recruited from shipyard and construction trades at five study centers in the United States. While the primary endpoint of the trial was the incidence of lung cancer, a number of questions about the natural history of asbestos-related disease will also be addressed. The mean age at entry into the trial was 57 years and the mean duration of follow-up on active intervention was 4 years. With the exception of 133 never-smoker pilot participants (3%), all subjects recruited were by intention current (38%) or ex-smokers (58%), with a mean cumulative smoking exposure at entry of 43 pack-years. Mean years from first asbestos exposure were 35, and mean duration of asbestos exposure in a high-risk trade was 19 years. The distribution of radiographic abnormalities was as follows: normal, 34%; parenchymal opacities (ILO profusion score >1/0) alone, 18%; pleural thickening alone, 27%; both parenchymal opacities and pleural thickening, 21%. The CARET cohort, when compared to previously reported asbestos-exposed cohorts, is characterized by substantial asbestos exposure and high proportion of asbestos-related radiographic findings. The active intervention was halted in 1996, after a mean duration of 40 years. Passive follow-up of the cohort will continue until the year 2000. Am. J. Ind. Med. 32:573-581, 1997. © 1997 Wiley-Liss, Inc.     

Production of β-Cyclocitral and Its Precursor β-Carotene in Microcystis aeruginosa: Variation at Population and Single-Cell Levels

Bloom-forming cyanobacteria produce and release odorous compounds and pose threats to the biodiversity of aquatic ecosystem and to the drinking water supply. In this study, the concentrations of β-cyclocitral in different bacterial growth phases were investigated using GC–MS to determine the growth stage of Microcystis aeruginosa at high risk for β-cyclocitral production. Moreover, the synchronicity of the production of β-cyclocitral and its precursor β-carotene at both population and single-cell levels was assessed. The results indicated that β-cyclocitral was the main odorous compound produced by M. aeruginosa cells. The intracellular concentration of β-cyclocitral (C_β-cc) as well as its cellular quota (Q_β-cc) increased synchronously in the log phase, along with the increase of cell density. However, they reached the maximum values of 415 μg/L and 10.7 fg/cell in the late stationary phase and early stationary phase, respectively. The early stage of the stationary phase is more important for β-cyclocitral monitoring, and the sharp increase in Q_β-cc is valuable for anticipating the subsequent increase in C_β-cc. The molar concentrations of β-cyclocitral and β-carotene showed a linear relationship, with an R² value of 0.92, suggesting that the production of β-cyclocitral was linearly dependent on that of β-carotene, especially during the log phase. However, the increase in Q_β-cc was slower than that in β-carotene during the stationary phase, suggesting that β-cyclocitral production turned to be carotene oxygenase-limited when the growth rate decreased. These results demonstrate that variations of β-cyclocitral production on a single-cell level during different bacterial growth phases should be given serious consideration when monitoring and controlling the production of odorous compounds by M. aeruginosa blooms.     

The Risk of Helicobacter Pylori Infection and Atrophic Gastritis from Food and Drink Intake: a Cross-sectional Study in Hokkaido

One-hundred and fifteen subjects were diagnosed with Helicobacter pylori (HP) infection and 93 subjects with ‍atrophic gastritis (AG) from tests of HP antibodies or serum levels of pepsinogen I and pepsinogen II involving 210 ‍inhabitants, who participated in the health check-up program. Logistic regression analysis found that refreshing ‍(isotonic) beverages significantly reduced the risk of HP infection (odds ratio: 0.767, 95%C.I.: 0.616-0.956). A higher ‍frequency of intake for margarine (odds ratio: 1.413, 95%C.I.: 1.080-1.848), cheese (odds ratio: 1.416, 95%C.I.: ‍1.044-1.920), Tsukemono (odds ratio: 1.277, 95%C.I.: 1.000-1.631) or Cola-beverages (odds ratio: 1.471, 95%C.I.: ‍1.051-1.239) showed a significantly increased risk of AG. In addition, high serum values of â-carotene (odds ratio: ‍0.691, 95%C.I.: 0.498-0.958), linoleic acid (odds ratio: 0.594, 95%C.I.: 0.382-0.924), and ã-linolenic acid (odds: 0.987, ‍95%C.I.: 0.976-0.998) were found to reduce the risk of AG, but not HP infection. Furthermore, these results suggest ‍that a more frequent intake of margarine, Tsukemono (pickled vegetables), or Cola-beverages may be a risk factor ‍for AG, while foods rich in carotenes, such as, â-carotene and n-6PUFAs, such as ã-linolenic acid, may reduce the ‍risk of AG.     

脱落酸对盐藻SZ-05药理活性成分积累的影响

目的阐明脱落酸对盐藻SZ-05药理活性成分积累的影响。方法以脱落酸加入盐藻SZ-05培养体系,在盐胁迫条件下检测盐藻SZ-05药理活性成分。其中β-胡萝卜素用HPLC法检测,多糖用硫酸-蒽酮法检测。结果脱落酸明显的促进了盐藻的生长,使盐藻SZ-05的生物量提高了16．94％,β-胡萝卜素提高了11．16％;多糖提高了22．31％,其中胞外多糖的增长量为8．01％。结论脱落酸能显著提高盐藻SZ-05药理活性物质的积累并能显著降低藻细胞在胁迫条件下的脂质过氧化,提高氧化酶的活性。     

Effect of Carotenoids on Paraoxonase-1 Activity and Gene Expression

Paraoxonase 1 (PON1) is an antioxidant enzyme attached to HDL with an anti-atherogenic potential. It protects LDL and HDL from lipid peroxidation. The enzyme is sensitive to various modulating factors, such as genetic polymorphisms as well as pharmacological, dietary (including carotenoids), and lifestyle interventions. Carotenoids are nutritional pigments with antioxidant activity. The aim of this review was to gather evidence on their effect on the modulation of PON1 activity and gene expression. Carotenoids administered as naturally occurring nutritional mixtures may present a synergistic beneficial effect on PON1 status. The effect of carotenoids on the enzyme depends on age, ethnicity, gender, diet, and PON1 genetic variation. Carotenoids, especially astaxanthin, β-carotene, and lycopene, increase PON1 activity. This effect may be explained by their ability to quench singlet oxygen and scavenge free radicals. β-carotene and lycopene were additionally shown to upregulate PON1 gene expression. The putative mechanisms of such regulation involve PON1 CpG-rich region methylation, Ca(2+)/calmodulin-dependent kinase II (CaMKKII) pathway induction, and upregulation via steroid regulatory element-binding protein-2 (SREBP-2). More detailed and extensive research on the mechanisms of PON1 modulation by carotenoids may lead to the development of new targeted therapies for cardiovascular diseases.     

Carotenoid transporter CD36 expression depends on hypoxia-inducible factor-1α in mouse soleus muscles

Dietary β-carotene induces muscle hypertrophy and prevents muscle atrophy in red slow-twitch soleus muscles, but not in white fast-twitch extensor digitorum longus (EDL) muscles and gastrocnemius muscles. However, it remains unclear why these beneficial effects of β-carotene are elicited in soleus muscles. To address this issue, we focused on carotenoid transporters in skeletal muscles. In mice, Cd36 mRNA levels were higher in red muscle than in white muscle. The siRNA-mediated knockdown of CD36 decreased β-carotene uptake in C2C12 myotubes. In soleus muscles, CD36 knockdown inhibited β-carotene-induced increase in muscle mass. Intravenous injection of the hypoxia marker pimonidazole produced more pimonidazole-bound proteins in soleus muscles than in EDL muscles, and the hypoxia-inducible factor-1 (HIF-1) α protein level was higher in soleus muscles than in EDL muscles. In C2C12 myotubes, hypoxia increased the expression of CD36 and HIF-1α at the protein and mRNA levels, and HIF-1α knockdown reduced hypoxia-induced increase in Cd36 mRNA level. In soleus muscles, HIF-1α knockdown reduced Cd36 mRNA level. These results indicate that CD36 is predominantly involved in β-carotene-induced increase in soleus muscle mass of mice. Furthermore, we demonstrate that CD36 expression depends on HIF-1α in the soleus muscles of mice, even under normal physiological conditions.