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The antimicrobial properties of essential oil from various Santolina species have not been investigated enough in the previous studies dealing with the biological activities of medicinal plants. In Tunisia, Santolina chamaecyparissus L. (Asteraceae) is the only Santolina species recorded and is used as vermifuge and emmenagogue. The chemical composition, antibacterial and antifungal properties of essential oils from the flowerheads and roots of spontaneous S. chamaecyparissus growing in Tunisia and the chemical composition which leads to the Tunisian chemotype are investigated here for the first time. Essential oils isolated by hydro distillation from flowerheads and roots of S. chamaecyparissus were analyzed by GC and GC/MS. Two methods served for antimicrobial assays of the essential oils: diffusion in a solid medium and micro-well dilution assay. Antifungal tests were carried out by the agar incorporation method. Sixty-seven constituents were identified from the essential oil of the flowerhead. The major constituents were: 1,8-cineole and β-eudesmol. Two non identified compounds were present at the highest concentration in root oil. Flowerhead oil was characterized by high contents in monoterpenes and sesquiterpenes oxygenated compounds. The flowerhead essential oil demonstrated potent of antibacterial properties against Pseudomonas aeruginosa ATCC and Enterococcus faecalis ATCC, with MIC of 0.625 μg/ml. These findings demonstrate that the flowerhead essential oils of S. chamaecyparissus have excellent antibacterial properties and for this reason they could contribute to decrease the problem of microbial resistance to antibiotics.  相似文献   
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Chemokines are important mediators of cell migration, and thymus and activation-regulated chemokine (TARC/CCL17) and macrophage-derived chemokine (MDC/CCL22) are well-known typical inflammatory chemokines involved in atopic dermatitis (AD). (+)-Nootkatone is the major component of Cyperus rotundus. (+)-Nootkatone has antiallergic, anti-inflammatory, and antiplatelet activities. The purpose of this study was to investigate the effect of (+)-nootkatone on tumor necrosis factor α (TNF-α)/interferon γ (IFN-γ)-induced expression of Th2 chemokines in HaCaT cells. We found that (+)-nootkatone inhibited the TNF-α/IFN-γ-induced expression of TARC/CCL17 and MDC/CCL22 mRNA in HaCaT cells. It also significantly inhibited TNF-α/IFN-γ-induced activation of nuclear factor kappa B (NF-κB), p38 mitogen-activated protein kinase (MAPK), and protein kinase Cζ (PKCζ). Furthermore, we showed that PKCζ and p38 MAPK contributed to the inhibition of TNF-α/IFN-γ-induced TARC/CCL17 and MDC/CCL22 expression by blocking IκBα degradation in HaCaT cells. Taken together, these results suggest that (+)-nootkatone may suppress TNF-α/IFN-γ-induced TARC/CCL17 and MDC/CCL22 expression in HaCaT cells by inhibiting of PKCζ and p38 MAPK signaling pathways that lead to activation of NF-κB. We propose that (+)-nootkatone may be a useful therapeutic candidate for inflammatory skin diseases such as AD.  相似文献   
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Mitochondrial hexokinase (HK) and creatine kinase (CK) known to form complexes with a voltage dependent anion channel (VDAC) have been reported to increase cell death resistance under hypoxia/anoxia. In this work we propose a new, non-Mitchell mechanism of generation of the inner and outer membrane potentials at anaerobic conditions. The driving force is provided by the Gibbs free energy of the HK and CK reactions associated with the VDAC–HK and the ANT (adenine nucleotide translocator)–CK–VDAC complexes, respectively, both functioning as voltage generators. In the absence of oxygen, the cytosolic creatine phosphate can be directly used by the ANT–CK–VDAC contact sites to produce ATP from ADP in the mitochondrial matrix. After that, ATP released through the fraction of unbound ANTs in exchange for ADP is used in the mitochondrial intermembrane space by the outer membrane VDAC–HK electrogenic complexes to convert cytosolic glucose into glucose-6-phosphate. A simple computational model based on the application of Ohm's law to an equivalent electrical circuit showed a possibility of generation of the inner membrane potential up to − 160 mV, under certain conditions, and of relatively high outer membrane potential without wasting of ATP that normally leads to cell death. The calculated membrane potentials depended on the restriction of ATP/ADP diffusion in narrow cristae and through the cristae junctions. We suggest that high inner membrane potential and calcium extrusion from the mitochondrial intermembrane space by generated positive outer membrane potential prevent mitochondrial permeability transition, thus allowing the maintenance of mitochondrial integrity and cell survival in the absence of oxygen.  相似文献   
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It has been shown that cholesterol modulates activity of protein kinase C (PKC), and PKC phosphorylates connexin 43 (Cx43) to regulate its function, respectively. However, it is not known whether cholesterol modulates function of Cx43 through regulating activity of PKC. In the present study, we demonstrated that cholesterol enrichment reduced the dye transfer ability of Cx43 in cultured H9c2 cells. Western blot analysis indicated that cholesterol enrichment enhanced the phosphorylated state of Cx43. Immunofluorescent images showed that cholesterol enrichment made the Cx43 distribution from condensed to diffused manner in the interface between the cells. In cholesterol enriched cells, PKC antagonists partially restored the dye transfer ability among the cells, downregulated the phosphorylation of Cx43 and redistributed Cx43 from the diffused manner to the condensed manner in the cell interface. In addition, reduction of cholesterol level suppressed PKC activity to phosphorylate Cx43 and restored Cx43 function in PKC agonist-treated cells. Furthermore, we demonstrated that cholesterol enrichment upregulated the phosphorylated state of Cx43 at Ser368, while PKC antagonists reversed the effect. Taken together, cholesterol level in the cells plays important roles in regulating Cx43 function through activation of the PKC signaling pathway.  相似文献   
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目的:探讨Src 激酶特异性抑制剂PP2 对人胆管癌QBC939 细胞侵袭能力的影响和机制。方法:通过Western Blotting 技术 检测PP2 对人胆管癌QBC939细胞中Src 激酶活化的影响;用Transwell 小室法观察PP2 对QBC939细胞的影响;用RT-PCR 和 Western Blotting 技术检测PP2对QBC939 细胞侵袭能力相关分子的作用。结果:实验组p-Src 蛋白表达水平明显低于对照组,差 异具有统计学意义(P<0.05);实验组QBC939 细胞体外侵袭能力较对照组显著降低,差异具有统计学意义(P<0.05);与对照组相 比,实验组E-cadherin 表达显著增强,CD44表达明显减弱,差异具有统计学意义(P<0.05)。结论:PP2 通过抑制Src 激酶活化,增 强E-cadherin 表达、减弱CD44 表达,抑制人胆管癌QBC939 细胞侵袭能力。  相似文献   
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With the world-wide increase of patients with renal failure, the development of functional renal replacement therapies have gained significant interest and novel technologies are rapidly evolving. Currently used renal replacement therapies insufficiently remove accumulating waste products, resulting in the uremic syndrome. A more preferred treatment option is kidney transplantation, but the shortage of donor organs and the increasing number of patients waiting for a transplant warrant the development of novel technologies. The bioartificial kidney (BAK) is such promising biotechnological approach to replace essential renal functions together with the active secretion of waste products. The development of the BAK requires a multidisciplinary approach and evolves at the intersection of regenerative medicine and renal replacement therapy. Here we provide a concise review embracing a compact historical overview of bioartificial kidney development and highlighting the current state-of-the-art, including implementation of living-membranes and the relevance of extracellular matrices. We focus further on the choice of relevant renal epithelial cell lines versus the use of stem cells and co-cultures that need to be implemented in a suitable device. Moreover, the future of the BAK in regenerative nephrology is discussed.  相似文献   
10.
A novel method for studying differential expression of multigene family members based on the high sensitivity of RT-PCR completed by restriction site polymorphism of DNA is described. This method allows the identification of specific patterns of expression of fourchalcone synthase genes in a Hunnegem poplar clone (Populus trichocarpa ×Populus deltoides).  相似文献   
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