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1.
Human T lymphocytes were found to be highly radiosensitive and complex cellular responses including apoptosis could be induced upon exposure to X‐ray irradiation. However, the mechanism of apoptosis associated with irradiation was not clear. In this study, a proteomic method was applied to investigation on alteration of proteome of human T‐lymphocyte cells after irradiation. The Jurkat cells were irradiated with 4 Gy X‐ray and the cell lysates were collected at different times after irradiation (6, 12, 18, 24 and 48 h). The whole proteins were separated and quantified by two‐dimensional fluorescence difference gel electrophoresis, and then the differentially expressed proteins were identified by mass spectrometry. 4 proteins exhibited significant irradiation‐induced difference in abundance, including L‐plastin, bifunctional purine biosynthesis protein, tubulin beta chain, beta‐actin. Differentially expressed proteins were reported to be directly or indirectly involved in the function of human T lymphocyte. Thus, this study might provide clues to identify proteins with biological significance related to irradiation.  相似文献   

2.
In the present study, we evaluated for the first time the photoprotective effect of fish bone bioactive peptides (FBBP) preparation isolated from silver carp (Hypophthalmichthys molitrix) discarded tissue using in vitro experimental models of skin cells exposed to ultraviolet B (UVB) irradiation and stressing agents. FBBP preparation was obtained by papain treatment of minced bones and centrifugal ultrafiltration, and the molecular weight (MW) distribution was characterized by size exclusion and reversed-phase high performance liquid chromatography (RP-HPLC). In vitro assessment of the effect of FBBP pretreatment in UVB-irradiated L929 fibroblasts and HaCaT keratinocytes revealed their cytoprotective activity. Their capacity to efficiently reduce reactive oxygen species (ROS) production and lipid peroxidation varied in a dose-dependent manner, and it was greater in fibroblasts. A decrease of proinflammatory cytokines secretion, in particular of tumor necrosis factor alpha (TNF-α), was found after FBBP pretreatment of THP-1-derived inflamed macrophages. Melanin production and tyrosinase activity investigated in UVB-irradiated Mel-Juso cells were lowered in direct relation to FBBP concentrations. FBBP fractions with high radical scavenging activity were separated by ion exchange chromatography, and two collagenic sequences were identified. All these results offer new scientific data on aquaculture fish bone-derived peptides confirming their ability to control the antioxidant, anti-inflammatory and pigmentation processes developed during UV irradiation of skin cells and recommend their use as valuable natural ingredients of photoprotective cosmeceutical products.  相似文献   

3.
联用胶内差异双向电泳(2D-DIGE)和高效液相色谱-电喷雾串联质谱(HPLC-nESI MS/MS)鉴定人角质形成细胞HaCaT应答中波紫外线(UVB)损伤的差异表达蛋白,筛选UVB影响皮肤细胞正常生理功能潜在的靶标蛋白.结果表明:UVB辐射明显影响HaCaT细胞的蛋白质表达谱,DeCyder软件在每块DIGE凝胶上...  相似文献   

4.
利用紫外-可见稳态吸收光谱, 稳态荧光发射光谱和激光光解瞬态光谱实验方法研究了磷酸基团在环丙沙星(CPX)光敏损伤DNA中的作用. 紫外-可见和稳态荧光光谱实验证实了磷酸根离子影响环丙沙星的稳态吸收和发射谱, 实验结果表明磷酸根是通过弱相互作用与环丙沙星结合. 我们还利用激光闪光光解实验分别研究了鸟苷(Gua), 脱氧鸟苷(dG)以及脱氧鸟苷酸(dGMP)对环丙沙星三线态(3CPX*)的影响, 通过对比实验证实了在环丙沙星光敏损伤dGMP中, 由于磷酸基团的存在, 导致了环丙沙星三线态吸收峰的改变, 从而改变了光敏损伤反应的途径. 通过研究发现, 光敏损伤途径的改变是由于dGMP结构上磷酸基团通过氢键与环丙沙星结合所造成的. 最后, 根据实验结果并对比Gua, dG和dGMP的结构, 提出了一个合理的磷酸基团的作用机理.  相似文献   

5.
6.
UVA irradiation is known to cause photoaging via production of reactive oxygen species (ROS) and activation of inflammatory processes. Previously, we have demonstrated that baicalin, a plant‐derived flavonoid possessing both antioxidant and anti‐inflammatory activity, protects mouse keratinocytes against damage from UVB irradiation. However, the role of baicalin in vivo has not been well studied, particularly in the setting of UVA irradiation. To explore the protective effects and mechanisms of baicalin treatment in mice after UVA irradiation, mice were exposed to acute and chronic doses of UVA irradiation with or without baicalin or vehicle. Skin samples were collected for histological staining, RNA isolation, flow cytometry and protein extraction. Our results demonstrate the protective effect of baicalin against UVA‐induced oxidative damage and inflammation in mouse skin. These effects are likely mediated via the TLR4 pathway, which may serve as a target for photochemoprevention against skin inflammation.  相似文献   

7.
Excessive reactive oxygen species (ROS) can oxidatively damage DNA to cause severe biological consequences. In the study, a natural flavonoid, myricitrin (myricetin‐3‐O‐α‐L‐rhamnopyranoside), was found to have a protective effect against hydroxyl‐induced DNA damage (IC50 159.86 ± 54.24 μg/mL). To investigate the mechanism, it was determined by various antioxidant assays. The results revealed that myricitrin could effectively scavenge ·OH, ·O2?, DPPH· (1,1‐diphenyl‐2‐picrylhydrazyl radical), and ABTS+· (2,2′‐Azino‐bis(3‐ethylbenzothiazoline‐6‐sulfonic acid) radicals (IC50 values were respectively 69.71 ± 5.93, 69.71 ± 5.93, 25.34 ± 2.14, and 1.71 ± 0.09 μg/mL), and bind Cu2+ (IC50 27.33 ± 2.36 μg/mL). Based on the mechanistic analysis, it can be concluded that: (i) myricitrin can effectively protect against hydroxyl‐induced DNA oxidative damage via ROS scavenging and deoxynucleotide radicals repairing approaches. Both approaches can be attributed to its antioxidant. From a structure‐activity relationship viewpoint, its antioxidant ability can be attributed to the ortho‐dihydroxyl moiety, and ultimately to the stability of its oxidized form ortho‐benzoquinone; (ii) its ROS scavenging is mediated via metal‐chelating, and direct radical‐scavenging which is through donating hydrogen (H·) and electron (e); and (iii) its protective effect against DNA oxidative damage may be primarily responsible for the pharmacological effects, and offers promise as a new therapeutic reagent for diseases from DNA oxidative damage.  相似文献   

8.
9.
A group of experimental rats under free radical damage are given various amounts of a lipophilic vitamin C(ascorbyl-6-1aurate, VC-12), and its parent compound, vitamin C, respectively. It has been found that the effects of 1.12 mmol/kg VC-12 on decreasing triglyceride(TG), total cholesterol(TC), low density lipopro-tein cholesterol (LDL-c) and lipid peroxide (LPO), and increasing high density lipoprotein cholesterol (HDL-c) and superoxide dismutase(SOD) are similar to those of 2.27 mmol/kg vitamin C. In addition, VC-12(1.12 mmol/kg) can increase the prostacycline(PGI2) and decrease the thromboxane(TXA2) even better than vita-min C(2. 27 mmol/kg). The above facts demonstrate that the antioxidative activity of VC-12 is higher than twice that of vitamin C. So, ascorbyl-6-1aurate may be a novel antioxidant drug against free radical damage.  相似文献   

10.
Phototherapy with broadband UVB is an effective treatment for inflammatory dermatoses. A newly developed fluorescent UVB lamp (Philips TL01) that emits a narrowband UVB around 311 nm was shown to be superior for the phototherapy of psoriasis. In order to contribute to the knowledge about the carcinogenic potential of this UVB source, we measured the DNA damage in lymphoblasts and keratinocytes induced by narrowband UVB and compared it with that by conventional broadband UVB using the single cell gel electrophoresis (comet as-say). At equal doses, broadband UVB produced more DNA damage than narrowband UVB. However, in phototherapy of psoriasis, up to 10-fold higher doses are used with TLO1. When therapeutically equivalent doses were compared (10-fold correction for narrowband UVB), we found only slight differences in the amount of DNA damage produced by broadband and narrowband UVB. This supports the already existing evidence that for phototherapy narrowband UVB is not more carcinogenic than broadband UVB.  相似文献   

11.
过氧亚硝酸根--一氧化氮和超氧根阴离子快速结合的产物,是生物体内产生的一种强氧化剂和细胞毒性物质,它可以介导生物大分子包括DNA、蛋白质和脂质的修饰和损伤。近年来,由于许多疾病条件下都发现大量过氧亚硝酸根诱导的蛋白质损伤产物,因此过氧亚硝酸根与蛋白质的相互作用引起了人们的广泛关注。本文详尽地介绍了过氧亚硝酸根介导蛋白质损伤对人体的病理作用和过氧亚硝酸根与蛋白质作用机制等方面的最新研究进展,并对未来过氧亚硝酸根与蛋白质相互作用的研究作了展望。  相似文献   

12.
Mannosylerythritol lipids (MELs) may prevent skin barrier damage, although their protective mechanisms and active monomeric constituents remain unclear. Here, three MELs were extracted from Candida antarctica cultures containing fermented olive oil then purified using silica gel-based column chromatography and semipreparative HPLC. All three compounds (MEL-A, MEL-B, MEL-C) were well separated and stable, and reliable materials were used for NMR and HRESIMS chemical structure determinations and for assessing MELs’ protective effects against skin damage. Notably, MEL-B and MEL-C effectively protected HaCaT cells from UVB-induced damage by upregulating the contents of filaggrin (FLG) and transglutaminase-1 (TGM1), as determined via ELISA. Moreover, MEL-B treatment (20 μg/mL) of UVB-irradiated HaCaT cells led to the upregulation of both the expression of mRNA genes and the key proteins FLG, LOR, and TGM1, which are known to be decreased in damaged skin cells. Additionally, histopathological analysis results revealed a markedly reduced intracellular vacuolation and cell damage, reflecting improved skin function after MEL-B treatment. Furthermore, immunofluorescence results revealed that MEL-B protected EpiKutis® three-dimensional cultured human skin cells from sodium dodecyl sulfate-induced damage by up-regulating FLG, LOR, and TGM1 expression. Accordingly, MELs’ protection against skin barrier damage depended on MEL-B monomeric constituent activities, thus highlighting their promise as beneficial ingredients for use in skin-care products.  相似文献   

13.
Solar ultraviolet (UV) radiation, particularly its UVB (280–320 nm) spectrum, is the primary environmental stimulus leading to skin carcinogenesis. Several botanical species with antioxidant properties have shown photochemopreventive effects against UVB damage. Costa Rica's tropical highland blackberry (Rubus adenotrichos) contains important levels of phenolic compounds, mainly ellagitannins and anthocyanins, with strong antioxidant properties. In this study, we examined the photochemopreventive effect of R. adenotrichos blackberry juice (BBJ) on UVB‐mediated responses in human epidermal keratinocytes and in a three‐dimensional (3D) reconstituted normal human skin equivalent (SE). Pretreatment (2 h) and posttreatment (24 h) of normal human epidermal keratinocytes (NHEKs) with BBJ reduced UVB (25 mJ cm?2)‐mediated (1) cyclobutane pyrimidine dimers (CPDs) and (2) 8‐oxo‐7,8‐dihydro‐2′‐deoxyguanosine (8‐oxodG) formation. Furthermore, treatment of NHEKs with BBJ increased UVB‐mediated (1) poly(ADP‐ribose) polymerase cleavage and (2) activation of caspases 3, 8 and 9. Thus, BBJ seems to alleviate UVB‐induced effects by reducing DNA damage and increasing apoptosis of damaged cells. To establish the in vivo significance of these findings to human skin, immunohistochemistry studies were performed in a 3D SE model, where BBJ was also found to decrease CPDs formation. These data suggest that BBJ may be developed as an agent to ameliorate UV‐induced skin damage.  相似文献   

14.
Advanced glycation end products (AGEs) have recently been increasingly discussed as one factor of skin aging. In this study, we investigated the effects of Cirsium japonicum flower (CFE) extract on glycation in relation to skin aging and skin elasticity. Moreover, we learned the main active constituent of CFE that has effects against glycation. To demonstrate the effects of CFE on glycation, we carried out an in vitro glycation study, 3-dimensional culture, and clinical study. As a result, CFE inhibited formation of AGEs in both bovine serum albumin (BSA)/glucose glycation system and aldehyde-derived glycation system. Moreover, CFE reduced Nε-(carboxymethyl), lysine (CML), and carbonylated proteins that increased by glycation. Furthermore, CFE broke crosslinks of collagen–AGEs and inhibited the increase of matrix metalloproteinase-1 (MMP-1) gene expression by AGEs. In the 3D culture condition, CFE restored the reduction of collagen gel contraction by glycation. Moreover, apigenin was detected as the main active constituent in CFE that has anti-glycation effects. In the clinical study, we confirmed that CFE has effects on skin wrinkles and skin elasticity. Our findings suggest that CFE can be used as a cosmetic or cosmeceutical ingredient for improving skin elasticity and wrinkles. Regulation of AGEs can be an interesting target for anti-aging.  相似文献   

15.
The barrier function of the skin is largely due to the stratum corneum which is essentially composed of lipids. Different external factors, such as UV irradiation, affect this skin layer and are responsible for a destabilization of the supramolecular organization of its constituted lipids. In this work, mass spectrometry and infrared spectroscopy are combined to study the correlation between the formation of oxidative compounds by UV irradiation and the lipid organization. Experiments were carried out on unsaturated lipids in film or solution form, exposed to UVA or UVB irradiation. UV exposure leads to the formation of oxygenated entities in the case of lipids with an unsaturated fatty acid moiety, resulting in a decrease in their packing which is greater when the lipids are in solution. The packing decrease is even greater following UVB irradiation.  相似文献   

16.
吴萍  蔡习美  颜朝国 《有机化学》2006,26(12):1673-1676
氯化N-氰甲基吡啶在微波辐射下于醋酸铵/醋酸体系中和4种查尔酮反应, 或直接与芳香醛和取代苯乙酮一锅煮反应, 高产率地生成了2-氨基-4,6-二芳基吡啶衍生物. 化合物的结构经过IR, 1H NMR和HPLC-MS的表征.  相似文献   

17.
The present study reports beneficial effect of hydroxytyrosol (HT) against arsenic (As)-induced oxidative stress in the rat brain. Rats were orally administered with sodium arsenite dissolved in distilled water (25 ppm, by oral gavage) for 8 weeks or HT (10 mg/kg b. wt.) in combination with As. Results showed increase in protein oxidation and lipid peroxidation, while catalase and superoxide dismutase (SOD) activities as well as GSH content were decreased after As exposure in rat brain. Fourier transform infrared analysis showed significant alteration in peak area values that also validated the oxidative damage to lipids and proteins. In addition, As exposure caused increase in protein expression of caspase-3 and Bax, while Bcl-2 expression was downregulated resulting in translocation of cytochrome c from mitochondria to cytosol. Treatment of HT with As reversed protein oxidation, lipid peroxidation, and increased GSH content as well as catalase and SOD activities. Administration of HT also prevented translocation of cytochrome c from mitochondria and increased mitochondria/cytosol ratio of cytochrome c. Hence, treatment of HT with As improved antioxidant system and efficiently lowered the generation of oxidative stress in rat brain.  相似文献   

18.
Brimonidine at 0.18%, 1% and 2% concentrations applied topically in hairless mice significantly decreased tumor burden and incidences of erythema, flaking, wrinkling and skin thickening induced by UVR. The unbiased median week to tumor ≥1 mm was increased by the 1% and 2% concentrations. The tumor yield was reduced by all concentrations at week 40 for all tumor sizes but the ≥4 mm tumors with the 0.18% concentration. At week 52, the tumor yield was reduced for all tumor sizes and all brimonidine concentrations. The tumor incidence was reduced by all concentrations at week 40 for all tumor sizes, but the ≥4 mm tumor with the 0.18% concentration and at week 52 for all tumor sizes with the 1% and 2% concentrations and with the 0.18% concentration only for the ≥4 mm tumors. Reductions in ≥4 mm tumor incidences compared to the vehicle control group were 54%, 91% and 86% by week 52 for the 0.18%, 1% and 2% concentrations, respectively. Brimonidine at 2% applied 1 h before or just after UVB irradiation on hairless mice decreased epidermal hyperplasia by 23% and 32% and epithelial cell proliferation by 59% and 64%, respectively, similar to an epidermal growth factor receptor (EGFR) inhibitor.  相似文献   

19.
Dermal macrophages containing melanin increase skin pigmentation since dermal melanin removal is slower than epidermal melanin removal. Lymphatic vessels are also involved in melanin clearance. We evaluated whether radiofrequency (RF) irradiation induced an increase in HSP90, which promotes lymphangiogenesis by activating the BRAF/MEK/ERK pathway and decreasing tyrosinase activity, in the UV-B exposed animal model. The HSP90/BRAF/MEK/ERK pathway was upregulated by RF. Tyrosinase activity and the VEGF-C/VEGFR 3/PI3K/pAKT1/2/pERK1/2 pathway, which increase lymphangiogenesis, as well as the expression of the lymphatic endothelial marker LYVE-1, were increased by RF. Additionally, the number of melanin-containing dermal macrophages, the melanin content in the lymph nodes, and melanin deposition in the skin were decreased by RF. In conclusion, RF increased HSP90/BRAF/MEK/ERK expression, which decreased tyrosinase activity and increased lymphangiogenesis to eventually promote the clearance of dermal melanin-containing macrophages, thereby decreasing skin pigmentation.  相似文献   

20.
Abstract— Ultraviolet A (UVA,315–400 nm) radiation is known to be a complete carcinogen, but in contrast to UVB (280-315 nm) radiation, much of the cell damage is oxygen dependent (mediated through reactive oxygen species), and the dominant premutational DNA lesion(s) remains to be identified. To investigate further the basic differences in UVA and UVB carcinogenesis, we compared in vivo cellular responses, viz. cell cycle progression and transient p53 expression in the epidermis, after UVA1 (340-400 nm) exposure with those after broadband UVB exposure of hairless mice. Using flow cytometry we found a temporary suppression of bromodeoxyuridine (BrdU) uptake in S-phase cells both after UVB and UVA1 irradiation, which only in the case of UVB is followed by an increase to well over control levels. With equally erythemogenic doses (1-2 MED), the modulation of BrdU uptake was more profound after UVB than after UVA1 irradiation. Also, a marked transient increase in the percentage of S-phase cells occurred both after UVB and after UVA1 irradiation, but this increase evolved more rapidly after UVA1 irradiation. Further, p53 expression increased both after UVB and UVA1 irradiations, with peak expression already occurring from 12 to 24 h after UVA1 exposure and around 24 h after UVB exposure. Overall, UVA1 radiation appears to have less of an impact on the cell cycle than UVB radiation, as measured by the magnitude and duration of changes in DNA synthesis and cells in S phase. These differences are likely to reflect basic differences between UVB and UVA1 in genotoxicity and carcinogenic action.  相似文献   

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