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1.
该研究检测了荔枝玫瑰酒的营养成分及其对D-半乳糖诱导的衰老小鼠皮肤抗氧化作用。60只小鼠随机分为正常组、D-半乳糖处理组、维生素C对照组及低剂量、中剂量和高剂量荔枝玫瑰酒组,饲喂12周后采样分析。结果表明,荔枝玫瑰酒含有丰富的多酚、黄酮、单宁及维生素C,分别为0.43 g/L、0.25 g/L、0.12 g/L和3.15 mg/100 mL;小鼠饲喂12周后,各组体质量无显著差异(P>0.05);高剂量荔枝玫瑰酒(45.00 mL/kg体质量)饲喂可显著提高衰老小鼠皮肤含水率、羟脯胺酸和胶原蛋白含量,降低丙二醛含量、谷胱甘肽过氧化物酶活性,提高谷胱甘肽含量、超氧化歧化酶和过氧化氢酶活性(P<0.05),维持皮肤较好的氧化还原稳态;同时通过恢复衰老小鼠皮肤抗氧化和胶原蛋白代谢相关基因表达,抑制了皮肤氧化损伤和胶原分解。  相似文献   

2.
Skin aging is a complex process that may be caused by factors that are intrinsic and extrinsic to the body. Ultraviolet (UV) radiation represents one of the main sources of skin damage over the years and characterizes a process known as photoaging. Among the changes that affect cutaneous tissue with age, the loss of elastic properties caused by changes in elastin production, increased degradation and/or processing produces a substantial impact on tissue esthetics and health. The occurrence of solar elastosis is one of the main markers of cutaneous photoaging and is characterized by disorganized and non‐functional deposition of elastic fibers. The occurrence of UV radiation‐induced alternative splicing of the elastin gene, which leads to inadequate synthesis of the proteins required for the correct assembly of elastic fibers, is a potential explanation for this phenomenon. Innovative studies have been fundamental for the elucidation of rarely explored photoaging mechanisms and have enabled the identification of effective therapeutic alternatives such as cosmetic products. This review addresses cutaneous photoaging and the changes that affect elastin in this process.  相似文献   

3.
作为一种肉品增值手段,成熟技术多年来在全球肉类工业中已被广泛应用。在宰后初期肌肉转化为可食用肉及后期成熟过程中所发生的一系列生化变化都会对肉的品质产生重要影响。因此,通过优化成熟方案并引入新型成熟技术来有效提升肉品品质(特别是嫩度)尤为重要。近年来,对肉品宰后生理生化机制的探索和新型成熟技术的研究始终是该领域的热点,然而目前鲜见对该方面最新进展的综合性报道。因此,本文系统地总结了对肉品质起决定性作用的宰后早期生理生化变化,概述了现行不同成熟方法(干法成熟和湿法成熟)对肉品质的影响,并对新型成熟技术的发展及其对品质的改善效果进行了综述,以期为满足消费者日益增长的高品质肉品消费需求和促进我国肉品加工行业的发展提供理论技术指导和发展思路。  相似文献   

4.
It has been proposed that oxygen free radicals are involved in skin aging. This paper describes a new method for the evaluation of oxygen free radical scavenging by cosmetic products. It is based on the measurement, by gas chromatography, of ethylene produced during the oxidation of methionine by the hydroxyl radical. OH· is produced by an iron catalyzed superoxide-driven Fenton reaction in which superoxide is obtained by photochemical oxygen reduction. The cosmetic is applied, together with methionine, riboflavine, NADH, FeCl3 and EDTA, on a glass microfibre filter and submitted to UVA exposure through a quartz cell. Ethylene is then measured from aliquots of the atmosphere inside the cell. Catalase or Desferal completely inhibits ethylene production. SOD or high concentrations of hydroxyl radical scavengers (Mannitol, DMSO etc. ) afford a partial protection. Thus the efficiency of O2·, H2O2 and OH· scavengers and iron chelators can be measured. The main advantage of this test is that it is performed in conditions which simulate skin during UV exposure (e.g. air and UV exposed thin layer). Furthermore, as it is non-invasive, it can also be applied to human skin in vivo.  相似文献   

5.
该文主要从白酒老熟内在机理和外在因素之间的联系论述了新酒在贮存过程中物质的变化,并分析了影响老熟过程中缔合、酯化、氧化等物质变化的因素以及这些变化之间的相互作用。总结了白酒老熟机理的相关研究以及关于氢键的分子模拟研究,论述了运用分子模拟技术探究老熟深层机理的可行性,为白酒老熟的研究应用提供新思路。阐述了不同温度对白酒老熟过程的影响,主要分析了陶瓷容器和不锈钢容器的不同特性,对比了不同形状、不同环境的贮酒容器的效果。介于白酒老熟过程的复杂程度,将各个因素关联进行多元研究,旨在为白酒老熟相关研究提供新思路以及研究方法参考,推动白酒老熟机理深层次研究。  相似文献   

6.
考察刺梨对D-半乳糖引起的皮肤衰老模型小鼠的保护作用。实验测定服用刺梨期间动物皮肤水含量,服用结束后皮肤超氧化物歧化酶(superoxide dismutase,SOD)、丙二醛(malondialdehyde,MDA)、羟脯氨酸(hydroxyproline,HYP)及透明质酸(hyaluronic acid,HA)水平,同时对血清中抗氧化指标进行检测,并以苏木精-伊红染色法(hematoxylin-eosin staining,HE)观察皮肤组织结构。结果表明:在慢性注射D-半乳糖诱发皮肤衰老的小鼠模型中,刺梨能显著增加皮肤水含量,增强皮肤中SOD活力,减少脂质过氧化产物MDA的积累,增加HYP和HA水平,改善衰老皮肤的组织结构。可见,刺梨能显著减轻D-半乳糖引起的小鼠皮肤衰老。  相似文献   

7.
陈耕 《食品与机械》2021,37(2):169-172
通过皮下注射D-半乳糖制备衰老小鼠模型,在衰老小鼠背部脱毛皮肤上涂抹左旋芳樟醇精油(低、中、高剂量组左旋芳樟醇含量分别为2.5%,5.0%,7.5%),以维生素E为阳性对照,连续给药30 d;监测小鼠自主活动情况,观察小鼠背部皮肤皱纹分布,取小鼠血清及涂药处皮肤检测超氧化物歧化酶(SOD)活性和丙二醛(MDA)含量,同时检测皮肤中水分以及羟脯氨酸(Hyp)含量。结果表明,左旋芳樟醇精油可提高衰老小鼠自主活动能力,减少皮肤表面皱纹;显著提高衰老小鼠血清和皮肤的SOD活力,降低MDA含量,提高皮肤水分、Hyp含量,并且中剂量组(5.0%)效果最明显,与衰老模型组之间有差异显著(P<0.05)。表明左旋芳樟醇在小鼠体内具有显著的抗氧化及抗皮肤衰老活性;清除自由基,减少脂质过氧化是其抗皮肤衰老的机制之一。  相似文献   

8.
Recent reports on cocoa are appealing in that a food commonly consumed for pure pleasure might also bring tangible benefits for human health. Cocoa consumption is correlated with reduced health risks of cardiovascular diseases, hypertension, atherosclerosis, and cancer, and the health-promoting effects of cocoa are mediated by cocoa-driven phytochemicals. Cocoa is rich in procyanidins, theobromine, (?)-epicatechin, catechins, and caffeine. Among the phytochemicals present in consumed cocoa, theobromine is most available in human plasma, followed by caffeine, (?)-epicatechin, catechin, and procyanidins. It has been reported that cocoa phytochemicals specifically modulate or interact with specific molecular targets linked to the pathogenesis of chronic human diseases, including cardiovascular diseases, cancer, neurodegenerative diseases, obesity, diabetes, and skin aging. This review summarizes comprehensive recent findings on the beneficial actions of cocoa-driven phytochemicals in molecular mechanisms of human health.  相似文献   

9.
The ageing process is noticeable within all organs of the body and manifests itself visibly in the skin. Skin ageing is influenced by several factors including genetics, environmental exposure, hormonal changes and metabolic processes. Together these factors lead to cumulative alterations of skin structure, function and appearance. The functioning of the central nervous, immune, endocrine and cardiovascular systems, as well as the skin is also impaired with age. Chronologically, aged skin is thin, relatively flattened, dry and unblemished, with some loss of elasticity and age-related loss of architectural regularity. General atrophy of the extracellular matrix is reflected by a decrease in the number of fibroblasts. Reduced levels of collagen and elastin, with impaired organization are primarily because of decreased protein synthesis affecting types I and III collagen in the dermis, with an increased breakdown of extracellular matrix proteins. Oxidative stress is considered of primary importance in driving the ageing process. The original free radical theory of ageing purported that the molecular basis of ageing was derived from a lifetime accumulation of oxidative damage to cells resulting from excess reactive oxygen species (ROS) produced as a consequence of aerobic metabolism. Although the skin possesses extremely efficient anti-oxidant activities, during ageing, ROS levels rise and anti-oxidant activities decline. The ROS are necessary in multiple MAP kinase pathways and the induction of AP-1, in turn, up-regulates expression of matrix-metalloproteinases providing a plausible mechanism for the increased collagen degradation in aged human skin.  相似文献   

10.
The adverse effects of solar ultraviolet radiation (UVR) on normal skin are well established, especially in those with poorly melanized skin. Clinically, these effects may be classified as acute, such as erythema or chronic such as keratinocyte and melanocyte skin cancers. Apart from skin type genetics, clinical responses to solar UVR are dependent on geophysical (e.g., solar intensity) and behavioural factors. The latter are especially important because they may result in ‘solar overload’ with unwanted clinical consequences and ever greater burdens to healthcare systems. Correctly used, sunscreens can mitigate the acute and chronic effects of solar UVR exposure. Laboratory studies also show that sunscreens can inhibit the initial molecular and cellular events that are responsible for clinical outcomes. Despite public health campaigns, global trends continue to show increasing incidence of all types of skin cancer. Large-scale epidemiological studies have shown the benefits of sunscreen use in preventing skin cancer, though it is likely that sunscreen use has not been optimal in such studies. It is evident that without substantial changes in sun-seeking behaviour, sunscreen use is a very important part of the defence against the acute and chronic effects of solar exposure. Ideally, sunscreens should be able to provide the level of protection that reduces the risk of skin cancer in susceptible skin types to that observed in heavily melanized skin.  相似文献   

11.
Plant secondary metabolites such as flavonoids, isoflavones and phytosterols have been proposed as cosmetic ingredients displaying anti-aging effects. On the cellular level, however, the activity profiles of these ingredients are only partially understood. In this study we analyzed the effects of apple seed phytosterols on age-related structural and functional parameters using cell biochemical, molecular biological and bioengineering techniques. The expression of age-related genes was studied using skin equivalents and cDNA microarrays. Incubation of skin equivalents with apple seed phytosterols had significant consequences: (i) differential regulation of a set of genes associated with keratinocyte proliferation and differentiation, (ii) stimulation of hyaluronic acid synthesis, and (iii) increase of epidermal thickness. In vivo studies revealed that apple seed phytosterols improve skin elasticity and decrease skin roughness. In conclusion, apple seed phytosterols display distinct biological effects and significantly improve the structure and function of mature skin.  相似文献   

12.
Liang J  Pei X  Zhang Z  Wang N  Wang J  Li Y 《Journal of food science》2010,75(8):H230-H238
To investigate the long-term effects of marine collagen hydrolysate (MCH) from Chum Salmon skin on the aberrant collagen matrix homeostasis in chronological aged skin, Sprague-Dawley male rats of 4-wk-old were orally administrated with MCH at the diet concentrations of 2.25% and 4.5% for 24 mo. Histological and biochemical analysis revealed that MCH had the potential to inhibit the collagen loss and collagen fragmentation in chronological aged skin. Based on immunohistochemistry and western blot analysis, collagen type I and III protein expression levels in MCH-treated groups significantly increased as compared with the aged control group. Furthermore, quantitative real-time polymerase chain reaction and western blot analysis showed MCH was able to increase the expressions of procollagen type I and III mRNA (COL1A2 and COL3A1) through activating Smad signaling pathway with up-regulated TGF-βRII (TβRII) expression level. Meanwhile, MCH was shown to inhibit the age-related increased collagen degradation through attenuating MMP-1 expression and increasing tissue inhibitor of metalloproteinases-1 expression in a dose-dependent manner. Moreover, MCH could alleviate the oxidative stress in chronological aged skin, which was revealed from the data of superoxide dismutase activity and the thiobarbituric acid reactive substances level in skin homogenates. Therefore, MCH was demonstrated to have the protective effects on chronological skin aging due to the influence on collagen matrix homeostasis. And the antioxidative property of MCH might play an important role in the process.  相似文献   

13.
Intrinsic and extrinsic factors in skin ageing: a review   总被引:1,自引:0,他引:1  
As the proportion of the ageing population in industrialized countries continues to increase, the dermatological concerns of the aged grow in medical importance. Intrinsic structural changes occur as a natural consequence of ageing and are genetically determined. The rate of ageing is significantly different among different populations, as well as among different anatomical sites even within a single individual. The intrinsic rate of skin ageing in any individual can also be dramatically influenced by personal and environmental factors, particularly the amount of exposure to ultraviolet light. Photodamage, which considerably accelerates the visible ageing of skin, also greatly increases the risk of cutaneous neoplasms. As the population ages, dermatological focus must shift from ameliorating the cosmetic consequences of skin ageing to decreasing the genuine morbidity associated with problems of the ageing skin. A better understanding of both the intrinsic and extrinsic influences on the ageing of the skin, as well as distinguishing the retractable aspects of cutaneous ageing (primarily hormonal and lifestyle influences) from the irretractable (primarily intrinsic ageing), is crucial to this endeavour.  相似文献   

14.
沈棚  薛红玮 《中国酿造》2023,42(1):142-146
该研究考察了6种不同陈酿年份绍兴黄酒中挥发性风味物质和氨基酸的变化。通过固相微萃取-气相色谱-质谱联用(SPME-GC-MS)法对不同储存年份黄酒中挥发性风味物质进行分析,并通过全自动氨基酸分析仪检测了6种不同陈酿年份黄酒样品中的游离氨基酸。结果表明,黄酒中共鉴定出28种主要挥发性风味成分,分别为酯类13种、醇类4种、醛类5种、酮类2种、其他类4种;随着陈酿年份的增加,酒体愈加香气浓郁,酒味醇厚;醇类物质随着年份的增加而逐渐减少,酯类化合物随着年份的增加而增加。共检测出16种游离氨基酸,其氨基酸总含量为2.80~3.98 g/L,其中包括7种必需氨基酸以及9种非必需氨基酸,且必需氨基酸含量占氨基酸总含量的35%左右。通过实验发现,3~12年陈酿的黄酒中,随着陈酿年份的增长,酯类物质含量增加,游离氨基酸含量整体呈现上升趋势,而陈酿12年后,游离氨基酸含量急速下降。  相似文献   

15.
A vast array of cosmetic products are used routinely by consumers to alleviate a range of skin care problems. Consumer concern ranges from age-associated skin changes to complexion (e.g., spots and pimples) and dryness. However, a major cause for concern amongst European female consumers is skin dryness, which spans all age ranges and skin types. Utilizing instrumental procedures (Squametry and Image Analysis) the severity of skin dryness has been correlated with expert assessment and consumer perception of dryness. The sensitivity of these techniques enables one to follow the progression of dryness alleviation for a range of product forms (e.g., creams and lotions) as well as the purported mechanism of action of various ingredient systems (e.g., occlusivity, moisturization). While conventional cosmetic products are shown to be effective, these techniques can be used to aid in the assessment and formulation of more effective products.
Efficacité des produit cosmétiques à l'allégement d'un spectre d'états de peau sèche selon des measures cliniques et au moyen d'instruments  相似文献   

16.
Preparations from yeast have been used for a long time for cosmetic and pharmaceutical purposes. Studies have identified glucan from the cell wall of baker's yeast as an immunologically active agent. Glucan is a poly beta-( 1-3)-linked glucopyranose of high molecular weight and belongs to the class of compounds known as biological response modifiers. Glucan preparations are involved in the activation of the body's natural defence mechanisms and in the acceleration of the skin's wound healing processes. In the skin, Langerhans' cells and keratinocytes are the immunologically competent cells. Recent studies indicate that UV irradiation can deplete the number and viability of these cells (immunosuppression). The use of non-specific immune-stimulators, such as glucan, is a new approach for improving the function of stressed skin. We have developed a process to modify pure glucan from baker's yeast to carboxymethyl glucan (CM-glucan), a water soluble product suitable for topical formulations. The functional properties of this new compound have been investigated in vitro and in vivo. Cell culture experiments showed that CM-glucan protects skin cells against the depletion of antioxidant molecules upon UV-A irradiation and promotes the growth of keratinocytes. In placebo controlled studies with healthy volunteers, the pretreatment of skin with CM-glucan offered substantial protection against skin damage caused by a detergent challenge or UV-A irradiation. In addition, CM-glucan enhanced the renewal rate of the stratum corneum.  相似文献   

17.
白酒老熟是白酒生产工艺中最为重要的步骤之一。由于白酒自然老熟过程时间长、成本高,因此人们希望通过催陈技术使新酒在较短时间内达到老熟后白酒的色、香、味、格。白酒老熟是物理变化和化学变化共同作用的结果,白酒老熟过程中其酒体和微量成分都在发生变化。本文通过对主流香型白酒自然老熟过程中风味成分的变化及人工催陈技术进行综述,以期为促进白酒人工催陈技术开发提供理论基础。  相似文献   

18.
Since ancient times, human beings have been trying to protect their skin against the adverse effects of the sun. From the first mineral sunscreens used by Egyptians, to the current more sophisticated ultraviolet (UVA/UVB) organic sunscreens, progress has been made in terms of sun protection and deeper knowledge of skin physiology has been acquired in the process. The solar spectrum is composed of radiations of various wavelengths having specific, as well as overlapping effects on skin. UVB is mainly responsible for sunburn and DNA dimer formation that can lead to mutation. UVA generates oxidative reactions affecting DNA, proteins and lipids, and is also immunosuppressive. Recently, visible light and infrared radiation (IR) have been associated with oxidative damage and IR has been additionally linked to adverse heat effects on skin. Numerous other extrinsic factors, related to environment and lifestyle, also affect the appearance of skin, precipitating ageing. New molecular mechanisms linking sun and environmental factors to skin ageing have been identified: IR affects mitochondrial integrity and specific heat receptors also mediate some of its effects, tryptophan is a chromophore for UVB, and the aryl hydrocarbon receptor (AhR) is activated by light and xenobiotics to alter skin physiology. Integrating all these new elements is changing the way we think about skin extrinsic ageing. Is UVA/UVB sunscreen protection still enough for our skin?  相似文献   

19.
Whereas green tea has historically been consumed in high quantities in Northeast Asia, its popularity is also increasing in many Western countries. Green tea is an abundant source of plant polyphenols exhibiting numerous effects that are potentially beneficial for human health. Accumulating evidence suggests that green tea polyphenols confer protective effects on the skin against ultraviolet (UV) irradiation-induced acceleration of skin aging, involving antimelanogenic, antiwrinkle, antioxidant, and anti-inflammatory effects as well as prevention of immunosuppression. Melanin pigmentation in the skin is a major defense mechanism against UV irradiation, but pigmentation abnormalities such as melasma, freckles, senile lentigines, and other forms of melanin hyperpigmentation can also cause serious health and aesthetic issues. Furthermore, UV irradiation initiates the degradation of fibrillar collagen and elastic fibers, promoting the process of skin aging through deep wrinkle formation and loss of tissue elasticity. UV irradiation-induced formation of free radicals also contributes to accelerated photoaging. Additionally, immunosuppression caused by UV irradiation plays an important role in photoaging and skin carcinogenesis. In this review, we summarize the current literature regarding the antimelanogenic, antiwrinkle, antioxidant, and immunosuppression preventive mechanisms of green tea polyphenols that have been demonstrated to protect against UV irradiation-stimulated skin photoaging, and gauge the quality of evidence supporting the need for clinical studies using green tea polyphenols as anti-photoaging agents in novel cosmeceuticals.  相似文献   

20.
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