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1.
Zinc is an essential nutrient for human health. It plays key roles in maintaining protein structure and stability, serves as catalytic factor for many enzymes, and regulates diverse fundamental cellular processes. Zinc is important in affecting signal transduction and, in particular, in the development and integrity of the immune system, where it affects both innate and adaptive immune responses. The eye, especially the retina‐choroid complex, has an unusually high concentration of zinc compared to other tissues. The highest amount of zinc is concentrated in the retinal pigment epithelium (RPE) (RPE‐choroid, 292 ± 98.5 µg g?1 dry tissue), followed by the retina (123 ± 62.2 µg g?1 dry tissue). The interplay between zinc and inflammation has been explored in other parts of the body but, so far, has not been extensively researched in the eye. Several lines of evidence suggest that ocular zinc concentration decreases with age, especially in the context of age‐related disease. Thus, a hypothesis that retinal function could be modulated by zinc nutrition is proposed, and subsequently trialled clinically. In this review, the distribution and the potential role of zinc in the retina‐choroid complex is outlined, especially in relation to inflammation and immunity, and the clinical studies to date are summarized.  相似文献   

2.
Inflammation may increase cancer risk, therefore, we studied whether polyphenol‐rich Marie Ménard (MM) apples with reported anti‐inflammatory activity prevent 1,2‐dimethylhydrazine (DMH)‐induced colon carcinogenesis in rats and, likewise whether high‐fat (HF) diet promoting carcinogenesis, may affect inflammation. DMH‐induced rats were fed for 15 weeks with: an HF diet (23% corn oil w/w); an HF diet containing 7.6% w/w lyophilized MM (apple diet (AD)); a low‐fat (LF) diet and an HF diet containing piroxicam (PXC) (0.01% w/w) as control. Mucin depleted foci (MDF), precancerous lesions in the colon, were dramatically reduced in the AD, LF, and PXC groups compared with the HF. Peritoneal macrophage activation, an index of systemic inflammation, was significantly decreased in the AD, LF, and PXC groups. TNFα, iNOS, IL‐1β, IL‐6 m‐RNA expression in the colon, as well as CD68 cells and plasmatic PGE2 were lower in the AD, but not in the LF group. Apoptosis in the MDF of both the AD and LF‐fed rats was significantly higher than in HF rats. In conclusion, AD has a strong chemopreventive effect, reducing inflammation, and increasing apoptosis, while the chemopreventive effect of the LF diet seems mediated mainly by increased apoptosis in MDF.  相似文献   

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This paper reviews the physicochemical properties and nutritional significance of inulin fructans (oligofructose and inulin). These compounds are naturally present in a large number of food crops and serve in our diet as dietary fiber. Inulin fructans can be isolated and purified from the chicory root and used as ingredients in a large range of foods to improve structure and/or taste and to increase the intake of dietary fiber. Inulin fructans have a low caloric value, are safe, and generally well tolerated up to a level of 20 g/d. They exert a range of effects, which can be differentiated into direct effects on the gut and the intestinal flora and indirect systemic effects. Direct effects on the gut include prebiotic (bifidogenic) effects, improvement of bowel habits and bowel function in constipated subjects, increased colonic absorption of minerals (Ca and Mg), and secretion of satiety hormones. Indirect effects are on blood lipids, bone mineral content, the immune system, and energy homeostasis. These issues are discussed and it is argued that promising avenues for research are particularly in the areas of energy homeostasis and systemic low‐grade inflammation in relation to changes in the composition of the intestinal microbiota.  相似文献   

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Obesity is a complex disease and a major public health epidemic. Chronic, low‐grade inflammation is a common underlying feature of obesity and associated metabolic diseases; adipose tissue is a major contributor to this systemic inflammation. Evidence shows that obesity‐associated inflammation may originate from gut dysfunction, including changes in intestinal bacteria or microbiome profiles. Increasingly, food and plant bioactive compounds with antioxidant and anti‐inflammatory properties are proposed to ameliorate obesity‐associated inflammation. Among these, the health‐promoting effects of anthocyanin‐rich foods are of interest here. Specifically, this review summarizes the reported benefits of anthocyanins in obesity‐associated inflammation and underlying molecular mechanisms, including the role of gut microbiome and cell signaling pathways regulated by anthocyanins both in vivo and in vitro.  相似文献   

7.
BACKGROUND: Bamboo shoot is sensitive to chilling, and low‐temperature injury is a major limitation to its long‐term storage. Studies on the causes of postharvest deterioration in bamboo shoot are few. The aim of the present study was to evaluate the effects of ethylene and 1‐methylcyclopropene (1‐MCP) treatments on the physiological and biochemical responses of bamboo shoot and their ability as a postharvest tool to alleviate chilling injury and lignification of bamboo shoot during storage at 2 °C. RESULTS: Disease incidence, electrical conductivity (EC), respiration and ethylene production of control bamboo shoot increased after about 2–3 weeks of cold storage, associated with higher chilling injury (CI) index. Increased shoot firmness during cold storage was positively correlated with higher lignin and cellulose accumulation, and this accumulation of lignin in flesh tissue was also positively correlated with the activities of phenylalanine ammonia lyase (PAL), cinnamyl alcohol dehydrogenase (CAD) and peroxidase (POD). Ethylene treatment was associated with higher disease incidence, CI index, EC, respiration and ethylene production, enhanced lignin and cellulose accumulation and accelerated the activities of PAL, CAD and POD. In contrast, 1‐MCP treatment was associated with lower respiration, ethylene production, CI index and EC, reduced lignin and cellulose accumulation and retarded the activities of PAL, CAD and POD. CONCLUSION: The present findings throw light on the role of ethylene in postharvest physiological disorders such as chilling injury and lignification and suggest that 1‐MCP could be used commercially to control these disorders in bamboo shoot during cold storage. Copyright © 2007 Society of Chemical Industry  相似文献   

8.
The fruit of Viburnum dilatatum Thunb (gamazumi) has been shown to prevent oxidative injury induced by water immersion restraint stress (WIRS) in rats. In this study the effect of gamazumi crude extract (GCE) on antioxidant enzymatic activities in the plasma, liver and stomach of rats with WIRS was investigated to elucidate the mechanism of prevention of oxidative injury. Ulcer formation and lipid peroxidation were inhibited in rats supplied GCE for 2 weeks in comparison with rats supplied water. Although the activities of plasma, hepatic and gastric antioxidant enzymes in rats given water were decreased by WIRS, only slight changes were observed in rats given GCE. There was no difference in enzymatic activities between the water and GCE groups not subjected to WIRS. Furthermore, ferrous ascorbate‐induced oxidation in hepatic homogenate from rats given GCE was inhibited. These results suggest that ingestion of GCE does not induce antioxidant enzymes and that the absorbed antioxidant components of GCE have a direct effect on oxidative injury in the body. Copyright © 2003 Society of Chemical Industry  相似文献   

9.
The present study was conducted to evaluate how changes in leaf area affected vine growth, yield and grape quality of five‐year‐old potted Cabernet Sauvignon grapevines. At the beginning of flowering vines were randomly assigned to the following five treatments: untrimmed (control); shoot trimmed at either node 12 (T12) or node 6 (T6) with laterals either retained (R) or excised (X). Those four manipulations are abbreviated to: T12LR, T12LX, T6LR and T6LX, respectively. Total leaf area per vine was significantly lowered in T12LX and T6LX as compared to the other treatments, whereas lateral formation was able to offset foliage loss due to trimming in T12LR and T6LR with respect to control vines. T6LR also showed a more prolonged lateral node production. Yield per vine and its components did not differ significantly among treatments except for berry size, which was reduced in T6LR and T6LX. Grape ripening was severely retarded in T6LX, as shown by lower Brix, pH, colour and phenolics, and higher TA, tartrate and malate. A maturity delay was also shown in T6LR as lower soluble solids and total anthocyanins per berry in comparison with untrimmed vines. No difference in grape quality versus control was shown by the T12 treatments. Post‐trimming assimilation rates (A) clearly indicated a large compensation capacity of retained main leaves despite their mean age being higher than that calculated for main leaves sampled the same day on control vines. The assimilation rates recorded on lateral leaves increased proportionally with lateral shoot size and inversely to the number of main leaves retained with trimming. Based on present results, both the area and photosynthetic effectiveness of source leaves will drive overall vine responses to shoot trimming. For example, T6LX showed the worst performance with respect to the other treatments, in agreement with lowest leaf area, leaf‐to‐fruit ratio and oldest canopy. However, T6LR had a somewhat retarded ripening despite its non‐limiting leaf‐to‐fruit ratio, relatively young canopy and maximum whole‐canopy photosynthesis and efficiency at veraison. Under such circumstances, duration of growth and possible competition with the berry sugaring process may have played a role.  相似文献   

10.
The increase in world fish lipid request has made necessary the search for new fish species rich in polyunsaturated fatty acid (PUFA) that could be used as raw material for oil production. In this study, liver oils from the deep‐sea sharks Mustelus mustelus, Squalus acanthias, and Rhinobatos cemiculus were extracted and analyzed to describe their lipids characteristics. Lipid contents of shark livers ranged from 64.245 to 69.57%. Among minerals, potassium and sodium were the most abundant while unsaturated fatty acids (FAs) were dominant exceeding 55% of the total FAs. Omega‐3 PUFA (ω‐3 PUFA) profiles exhibited a dominance of eicosapentaenoic acid and docosahexaenoic acid. This study suggests that shark livers, actually considered as waste, may be an attractive source of ω‐3 PUFAs and a good source of carotenoids and phenolic compounds.

Practical applications

The production of EPA and DHA concentrates from residual sources of marine oils has unexplored potential of use in food industry and oil‐based nutraceutical production for obtaining health benefits can be achieved. The economic activities of fish residues can reduce inappropriate excessive fishing, reducing imports of fish oils while contributing to the ecosystem balance.  相似文献   

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The daily consumption of dietary omega‐3 PUFA is recommended by governmental agencies in several countries and by a number of health organizations. The molecular mechanisms by which these dietary PUFA affect health involve the enrichment of cellular membranes with long‐chain 20‐ and 22‐carbon omega‐3 PUFA that impacts tissues by altering membrane protein functions, cell signaling, and gene expression profiles. These changes are recognized to have health benefits in humans, especially relating to cardiovascular outcomes. Cellular membrane enrichment and health benefits are associated with the consumption of long‐chain omega‐3 PUFA found in marine oils, but are not generally linked with the consumption of alpha‐linolenic acid, the 18‐carbon omega‐3 PUFA found in plant seed oils. However, the supply of omega‐3 PUFA from marine sources is limited and may not be sustainable. New plant‐derived sources of omega‐3 PUFA like stearidonic acid‐soy oil from genetically modified soybeans and Ahiflower oil from Buglossoides arvensis seeds that are enriched in the 18‐carbon omega‐3 PUFA stearidonic acid are being developed and show promise to become effective as well as sustainable sources of omega‐3 PUFA. An example of changes in tissue lipid profiles associated with the consumption of Ahiflower oil is presented in a mouse feeding study.  相似文献   

13.
BACKGROUND: Monoacylglycerols (MAG) containing polyunsaturated fatty acids (PUFA), especially eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), have interesting applications. The enzymatic processing of such MAG directly from fish oils is highly interesting, integrating the processing of MAG and concentration of EPA and DHA. The aim of this study was to develop an efficient enzymatic glycerolysis system together with physical fractionation for the production of PUFA‐MAG from tuna oil. RESULTS: Novozym 435 was eventually selected after evaluation together with immobilized lipase AK in a tertiary alcohol‐based system. A further evaluation of solvent mixtures involving tertiary alcohols was made, taking ease of operation into consideration. It turned out that a number of mixtures gave a similar performance to that of tert‐butanol (TB). Basic reaction parameters were thoroughly evaluated. In the batch reaction system with TB as solvent, the recommended conditions were: glycerol/tuna oil 4:1 (mol/mol), TB/tuna oil 2:1 (wt/wt), 15 wt% Novozym 435, and temperature 40 °C. Under these conditions, the yield of MAG was up to 90% after 3 h incubation. Crude MAG from the production was fractionated to produce MAG with higher EPA and DHA content. Using acetone as solvent at 0 °C led to ca 50% yield of MAG but contained EPA and DHA up to 71% in comparison with ca 30% in tuna oil. CONCLUSION: Potentially practical process steps have been developed for the production of MAG containing a high content of EPA and DHA from natural fish oils with high efficiency and simplicity. Copyright © 2007 Society of Chemical Industry  相似文献   

14.
高产纤维素酶菌株的诱变选育和筛选   总被引:1,自引:0,他引:1       下载免费PDF全文
用青霉(Penicillium sp.)HK-003为原始菌,经亚硝基胍(NTG)、羟胺复合诱变,根据变异菌株菌落形态变化与产酶高低的关系。结合酶活力检测理化指标,筛选出一株高产稳定的纤维素酶菌株LX-435,其产酶能力由200U/mL提高到415U/mL,较出发菌株提高2.08倍。对该菌种进行了连续8次继代培养,结果表明其遗传性状稳定。  相似文献   

15.
目的:观察表没食子儿茶素没食子酸酯(epigallocatechin-3-gallate,EGCG)的抗肿瘤作用,研究EGCG对抗肿瘤药物阿霉素(adriamycin,ADR)所致小鼠心肌损伤的保护作用及其机制。方法:建立S180小鼠实体瘤模型,随机分为4 组:对照组、ADR组、EGCG组、EGCG+ADR组。分离肿瘤与心肌组织,分别测定组织内乳酸脱氢酶(lactate dehydrogenase,LDH)、肌酸激酶(creatine kinase,CK)和锰超氧化物歧化酶(manganese superoxidedismutase,MnSOD)的活性;流式细胞仪检测细胞凋亡、活性氧(reactive oxygen species,ROS)及线粒体膜电位。结果:与对照组相比,EGCG和ADR能显著增加肿瘤细胞凋亡作用,且ADR+EGCG作用更强。与ADR组相比,EGCG+ADR可显著降低心肌组织中ADR引起的LDH和CK活性的增加。同时,EGCG+ADR中可显著增加心肌组织的抗氧化酶MnSOD活性,减少ROS的生成,增加线粒体膜电位。结论:EGCG具有抗肿瘤作用,且与ADR合用可显著增强ADR抗肿瘤作用。同时可通过提高线粒体的抗氧化防御、削弱氧化应激、稳定线粒体膜电位,对ADR所致心肌损伤发挥保护作用。  相似文献   

16.
Anti-inflammatory activity of natural dietary flavonoids   总被引:1,自引:0,他引:1  
Pan MH  Lai CS  Ho CT 《Food & function》2010,1(1):15-31
Over the past few decades, inflammation has been recognized as a major risk factor for various human diseases. Acute inflammation is short-term, self-limiting and it's easy for host defenses to return the body to homeostasis. Chronic inflammatory responses are predispose to a pathological progression of chronic illnesses characterized by infiltration of inflammatory cells, excessive production of cytokines, dysregulation of cellular signaling and loss of barrier function. Targeting reduction of chronic inflammation is a beneficial strategy to combat several human diseases. Flavonoids are widely present in the average diet in such foods as fruits and vegetables, and have been demonstrated to exhibit a broad spectrum of biological activities for human health including an anti-inflammatory property. Numerous studies have proposed that flavonoids act through a variety mechanisms to prevent and attenuate inflammatory responses and serve as possible cardioprotective, neuroprotective and chemopreventive agents. In this review, we summarize current knowledge and underlying mechanisms on anti-inflammatory activities of flavonoids and their implicated effects in the development of various chronic inflammatory diseases.  相似文献   

17.
Human urinary trypsin inhibitor (UTI), a serine protease inhibitor, has been widely used in Japan as a drug for patients with acute inflammatory disorders such as septic shock and pancreatitis. Lipopolysaccharide (LPS) triggers the sepsis syndrome by activating monocytes to produce proinflammatory cytokines, including tumor necrosis factor alpha (TNFalpha), which potently stimulate the activation of neutrophils. The inhibitory mechanism of UTI on the systemic inflammatory response induced by the intraperitoneal injection of LPS in the kidney is unclear. This study was undertaken to examine the inhibitory effects of UTI on renal injury associated with the systemic inflammatory response induced by LPS stimulation, with emphasis on systemic TNFalpha and the activation of neutrophils in rat kidney. The systemic inflammatory response syndrome was induced by LPS treatment. Serum and renal TNFalpha, renal cytokine-induced neutrophil chemoattractant-1 (CINC-1) and myeloperoxidase (MPO) levels, as well as renal function after LPS stimulation, were evaluated. UTI (50,000 U/kg) inhibited LPS-induced increases in the serum and renal tissue levels of TNFalpha, as well as the renal tissue levels of CINC-1 and MPO after LPS stimulation. UTI (50,000 U/kg) also inhibited the production of serum TNFalpha associated with the systemic inflammatory response syndrome induced by LPS stimulation, thereby attenuating neutrophil infiltration into renal tissues and subsequent neutrophil-mediated renal injury. These findings may have important implications in understanding the biologic functions of UTI. UTI may prove useful in protecting against acute renal injury associated with a systemic inflammatory response.  相似文献   

18.
Abstract: Fatty acid composition and content of 2 forms of sockeye salmon Oncorhynchus nerka from lakes in Kamchatka Peninsula (Russia) were compared. One form of sockeye salmon was anadromous (“marine”), that is, adult fish migrated in ocean to feed and grow and than return in the lake to breed. Fish of another form, kokanee, never migrate in the ocean. Per cent levels of the main indicators of nutritive value, eicosapentaenoic acid (EPA, 20:5n‐3), and docosahexaenoic acid (DHA, 22:6n‐3), were significantly higher in the landlocked O. nerka. However, concentrations of EPA and DHA per wet weight of filets were higher in the marine form, because of the relatively higher content of sum of fatty acids in their muscle tissue. As concluded, fish fed in marine environment had higher contents of long‐chain n‐3 fatty acids per wet weight than fish of the same species, fed in fresh waters. In general, both the anadromous sockeye salmon and the landlocked kokanee salmon can be recommended for human diet as a valuable product concerning contents of EPA and DHA. Practical Application: The long‐chain polyunsaturated acids (PUFA) have been specifically recommended for humans to prevent cardiovascular disease and psychiatric disorders. Fish are known to be the main source of PUFA in human diet. Data on PUFA content in diverse food fish is essential to compare the benefits they offer for consumers’ health. We compared PUFA contents in 2 forms of popular food fish Oncorhynchus nerka, migrating sockeye salmon and landlocked kokanee salmon, and found that both forms are valuable product concerning PUFA content.  相似文献   

19.
《Journal of dairy science》2022,105(4):3687-3701
Adipose tissue (AT) is a central reservoir of energy stored in the form of lipids. In addition, AT has been recognized as an immunologically and endocrinologically active tissue of dairy cattle. The recent literature on AT biology of transition dairy cows has often focused on the possible negative effects that originate from excessive body fat. However, the highly efficient energy-storage capability of this tissue is also vital to the adaptability of dairy cattle to the change in nutrient availability, and to support lactation and reproduction. An excessive degree of mobilization of this tissue, however, is associated with high circulating fatty acid concentrations, and this may have direct and indirect negative effects on reproductive health, productivity, and disease risk. Furthermore, rapid lipolysis may be associated with postpartum inflammation. Research on the role of AT is complicated by the greater difficulty of accessing and measuring visceral AT compared with subcutaneous AT. The objective of this review is to provide a transition cow–centric summary of AT biology with a focus on reviewing methods of measuring AT mass as well as to describe the importance for production, health, and reproductive success.  相似文献   

20.
ABSTRACT

Obesity is a serious global health problem that is directly related to various morbidities manifestation. Intestinal dysbiosis has been implicated on obesity pathogenesis. Diet composition can alter gut microbiota, regardless of energy intake. Dietary fatty acids quality may affect gut microbiota composition, which in turn may affect host metabolic health. The mechanisms by which the different type of FFA modulate gut microbiota is yet poor elucidate and there is a lack of studies regard to this. Fatty acids may act in cell membrane, interfere with energy production, inhibit enzymatic activities, impair nutrient absorption and generate toxic compounds to cells, leading to growth inhibition or even bacterial death. The beneficial effect of the consumption of n-3 polyunsaturated fatty acids (PUFA) and conjugated linoleic acid (CLA) on microbiota, unlike n-6 PUFA and saturated fatty acids has been suggested. n-3 PUFA consumption promotes desirable changes on obese intestinal microbiota making it similar to that of normal weight individuals. More studies are needed to better understand the effect of CLA on microbiota and host health. Long term human controlled clinical trials must be conducted to allow us to understand the complex interaction between dietary fat, intestinal microbiota and obesity.  相似文献   

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