Radiofrequency irradiation attenuates angiogenesis and inflammation in UVB-induced rosacea in mouse skin

Rosacea is a skin inflammatory condition accompanied by cutaneous signs such as oedema, flushing, erythema, telangiectasia and pustules. Generally, rosacea is triggered by ultraviolet B (UVB) exposure. When exposed to UVB, skin epidermis thickens and produces elevated levels of pro-inflammatory cytokines, especially keratinocyte-related VEGF, a potent angiogenic factor. The upregulations of VEGF expression and its secretion promote the formation of new blood vessels and exacerbates rosacea. In this study, radiofrequency (RF) irradiation reduced keratinocyte proliferation in the epidermal layer, the expressions of pro-inflammatory cytokines, angiogenesis-related inflammatory factors and VEGF in our UVB-induced model of rosacea in vitro and in vivo. RF irradiation attenuated VEGF-induced angiogenesis-associated processes such as tube formation, cell migration and endothelial cell proliferation. Notably, blood vessel densities in the skins of UVB-treated mice and rosacea patients were significantly decreased by RF irradiation. These results provide experimental and molecular evidence regarding the effectiveness of RF irradiation for the treatment of rosacea.     

Melatonin compensates silencing of heat shock protein 70 and suppresses ultraviolet radiation‐induced inflammation in human skin ex vivo and cultured keratinocytes

Melatonin, a lipophilic compound synthesized and released from the pineal gland, effectively acts against ultraviolet radiation (UVR), one of the main inducers of epidermal damage, skin cancer, inflammation, and DNA photo damage. One of the common known stress protein induced by UVR is heat shock protein 70 (Hsp70), highly expressed in human keratinocytes, providing cellular resistance to such stressors. Here, using human full‐thickness skin and normal human epidermal keratinocytes (NHEK), we investigated the interaction of melatonin and Hsp70 toward UVR‐induced inflammatory and apoptotic responses. The following observations were made: (i) UVR upregulated Hsp70 gene expression in human epidermis while melatonin significantly inverted this effect, (ii) similar patterns of regulation were observed within Hsp70 protein level, and (iii) mechanistic studies involving silencing of Hsp70 RNA (Hsp70 siRNA) showed prominent decrease of IκB‐α (an inhibitor of NF‐κB) and enhanced gene expression of pro‐inflammatory cytokines (IL‐1β, IL‐6, Casp‐1) and pro‐apoptotic protein (Casp‐3) in NHEK. Parallel investigation using melatonin (10^?3 m ) significantly inverted these responses regardless depletion of Hsp70 RNA suggesting a compensatory action of this compound in the defense mechanisms. Our findings combined with data reported so far thus enrich existing knowledge about the potent anti‐apoptotic and anti‐inflammatory action of melatonin.     

窄谱中波紫外线治疗白癜风治疗参数选择

【摘要】 我国窄谱中波紫外线应用于白癜风治疗已有十余年，目前，其临床治疗参数尚缺乏统一标准，不规范的治疗不仅不能使患者从中获益，还易引起红斑、水疱、光老化等不良反应。基于世界白癜风工作组光疗委员会制定的窄谱中波紫外线治疗白癜风的专家共识，结合相关文献及临床治疗经验，本文从治疗频率、初始治疗剂量、连续治疗或中断治疗后剂量调整、平台期及疗程选择、可接受的最大光疗总次数等方面讨论窄谱中波紫外线治疗参数的选择，提高窄谱中波紫外线治疗白癜风的疗效。     

Glycyrrhizic acid prevents ultraviolet‐B‐induced photodamage: a role for mitogen‐activated protein kinases,nuclear factor kappa B and mitochondrial apoptotic pathway

Glycyrrhizic acid (GA), a natural triterpene, has received attention as an agent that has protective effects against chronic diseases including ultraviolet UV‐B‐induced skin photodamage. However, the mechanism of its protective effect remains elusive. Here, we used an immortalized human keratinocyte cell line (HaCaT) and a small animal model (BALB/c mice), to investigate the protective effects of GA against UV‐B‐induced oxidative damage, and additionally, delineated the molecular mechanisms involved in the UV‐B‐mediated inflammatory and apoptotic response. In the HaCaT cells, GA inhibited the UV‐B‐mediated increase in intracellular reactive oxygen species (ROS) and down‐regulated the release of pro‐inflammatory cytokines interleukin (IL)‐1α, ‐1β and ‐6, tumor necrosis factor (TNF)‐α and prostaglandin E2 (PGE2). GA inhibited UV‐B‐mediated activation of p38 and JNK MAP kinases, COX‐2 expression and nuclear translocation of NF‐κB. Furthermore, GA inhibited UV‐B‐mediated apoptosis by attenuating translocation of Bax from the cytosol to mitochondria, thus preserving mitochondrial integrity. GA‐treated HaCaT cells also exhibited elevated antiapoptotic Bcl‐2 protein, concomitant with reduced caspase‐3 cleavage and decreased PARP‐1 protein. In BALB/c mice, topical application of GA on dorsal skin exposed to UV‐B irradiation protected against epidermal hyperplasia, lymphocyte infiltration and expression of several inflammatory proteins, p38, JNK, COX‐2, NF‐κB and ICAM‐1. Based on the above findings, we conclude that GA protects against UV‐B‐mediated photodamage by inhibiting the signalling cascades triggered by oxidative stress, including MAPK/NF‐κB activation, as well as apoptosis. Thus, GA has strong potential to be used as a therapeutic/cosmeceutical agent against photodamage.     

黄芩素对UVB诱导HaCaT细胞光老化及相关p38信号通路的影响

目的:研究黄芩素对中波紫外线(UVB)诱导人皮肤角质形成细胞(HaCaT)光老化及相关p38丝裂原活化蛋白激酶(p38MAPK)信号通路的影响。方法:选择1×10~(-11),1×10~(-10),1×10~(-9),1×10~(-8),1×10~(-7),1×10~(-6),1×10~(-5),1×10~(-4),1×10~(-3)mol·L~(-1)9种浓度黄芩素作用于HaCaT细胞,噻唑蓝(MTT)法筛选出最佳有效浓度。经预实验筛选出辐射强度为0.5 mW·cm~(-2)的UVB,辐射时间为5 min建立光老化模型,筛选出最佳有效浓度作用于光老化模型,另设空白组MTT法检测各组细胞活性。超氧化物歧化酶(SOD),谷胱甘肽过氧化物酶(GSH-Px),过氧化氢酶(CAT)及丙二醛(MDA)试剂盒检测SOD,GSH-Px,CAT活性及MDA含量。实时定量荧光定量聚合酶连式反应(RT-PCR)及蛋白免疫印迹法(Western blot)分别检测各组细胞中mRNA及蛋白表达。结果:筛选出1×10~(-7),1×10~(-6),1×10~(-5)mol·L~(-1)黄芩素为最佳有效浓度;与空白组比较,UVB组对HaCaT细胞无明显的增殖作用。与UVB组比较,1×10~(-7),1×10~(-6),1×10~(-5)mol·L~(-1)黄芩素组对光老化模型无明显增殖作用。与空白组比较,UVB组SOD,GSH-Px及CAT活性明显的降低,MDA含量显著升高(P0.01);与UVB组比较,1×10~(-7),1×10~(-6),1×10~(-5)mol·L~(-1)黄芩素组SOD,GSH,CAT活性明显升高,MDA含量明显降低(P0.05,P0.01)。与空白组比较,UVB组肿瘤坏死因子-α(TNF-α)mRNA及TNF-α,磷酸化p38(p-p38)蛋白表达显著升高(P0.01);与UVB组比较,1×10~(-7),1×10~(-6),1×10~(-5)mol·L~(-1)黄芩素组TNF-αmRNA及TNF-α,p-p38蛋白表达明显降低(P0.05,P0.01)。结论:黄芩素对UVB诱导HaCaT细胞光老化保护作用主要是通过提高氧化酶活性以及阻断p38MAPK信号通路,抑制炎症因子产生。     

正交试验结合苯酚-硫酸法优选茅苍术中多糖的提取工艺

目的:优选出茅苍术中多糖成分的最佳水提取工艺。方法:采用水提醇沉法提取多糖成分,以苯酚-硫酸法测定总多糖的含量。以总多糖含量为评价指标,以提取时间、提取次数和加水量为影响因素,采用正交试验优选茅苍术中总多糖的最佳提取工艺。结果:茅苍术中多糖成分的最佳提取工艺为水提取3次,每次加水10倍量,每次提取1.0小时。结论:正交试验结合苯酚-硫酸法考察茅苍术中多糖成分的最佳水提取工艺稳定可行。     

人转化生长因子β3的构建

目的:获取人转化生长因子β₃的编码基因,开发抗衰老的皮肤药物。 方法：采用重叠PCR的方法,设计4对引物,进行4次PCR合成人转化生长因子β₃的编码基 因。 结果：4次PCR后,经2％的琼脂糖凝胶电泳可见一357 bp的条带,将电泳产物回收,连接入pMD-18T载体,经测序分析证实,所获得DNA片段为人转化生长因子β₃的编码基因。 结论：利用重叠PCR方法能够成功构建人转化生长因子β₃的编码基因。