内毒素对人皮肤成纤维细胞转化生长因子-β1和γ-干扰素分泌的诱导作用及意义

目的：观察细菌内毒素（LPS）对体外培养人皮肤成纤维细胞分泌转化生长因子-β1（TGF-β1）和γ-干扰素（IFN-γ）作用的影响,探讨其在增生性瘢痕形成中的可能作用。方法：取增生性瘢痕患者的正常皮肤进行成纤维细胞培养,分别用终浓度为0．005、0．010、0．050、0．100、0．500和1．000μg／ml的大肠杆菌LPS（E．coli055：B5）刺激,传代至表型稳定（第8代）。酶联免疫吸附法测定LPS刺激后8、24和γ2h细胞培养上清液中TGF-β1和IFN-γ含量的变化。阴性对照为DMEM培养基;阳性对照为增生性瘢痕成纤维细胞培养上清液。结果：随着LPS浓度的增加（0．005～0．100μg／ml）,各时间点细胞培养上清液中TGF-β1的含量增加,而IFN-γ的含量降低,呈明显量一效依赖关系,在0．100μg／ml浓度时作用最为明显,TGF-β1、IFN-γ的含量与阳性对照相近（P〉0．05）。但随着浓度的进一步增加（0．500μg／ml）,这一作用开始下降,当刺激浓度达到（1．000μg／ml）时,则呈相反作用。结论：一定浓度的LPS刺激可促进成纤维细胞分泌TGF-β1并抑制IFN-γ的分泌,这可能是增生性瘢痕形成的重要机制之一。     

交感神经递质NE对内毒素诱导大鼠kupffer细胞TNF-α/IL-1β表达的影响

目的探讨交感神经递质去甲肾上腺素对体外培养大鼠kupffer细胞TNF-α、IL-1β炎症相关细胞因子表达的影响。方法分离大鼠kupffer细胞体外分三组培养,经体外培养48h后,给予外源性内毒素（LPS10μg／m1）刺激,同时给予不同浓度的去甲。肾上腺素（0．1μmol／L～10μmol／L）分别作用12h,运用定量逆转录多聚酶链反应检测各处理组TNF-α和IL-1β mRNA的表达,ELISA检测细胞培养上清TNF-α IL-1β蛋白的表达。结果同时给予LPS（10μg/ml）刺激和去甲肾上腺素（1μmol／L及10μmol／L）作用后,kupffer细胞培养上清TNF-α和IL-1β蛋白较LPS组显著增高（P〈0．05）;TNF-α mRNA表达分别较LPS组增加50．9％（P〈0．05）和59．1％（P〈0．05）;IL-1β mRNA较LPS组表达增加53．7％（P〈0．05）和57．8％（P〈0．05）。结论应激浓度的去甲肾上腺素能增加内毒素诱导大鼠kupffer细胞TNF-α、IL-1β表达,具有促炎效应。     

羧甲基壳多糖对瘢痕疙瘩成纤维细胞增殖和胶原合成的影响

目的 观察羧甲基壳多糖（carboxymethyl-chitosan，CM-CH）对体外培养的瘢痕疙瘩成纤维细胞（keloid fibroblasts，KFB）增殖和胶原合成的作用，探讨其治疗瘢痕疙瘩的机制。方法 采用四噻唑蓝（methylthiazoletrazolium，MTT）测定法和羟脯氨酸比色法（hydroxyproline，HP）测定不同浓度CM-CH作用KFB后对其增殖和上清液中胶原合成的影响。结果 CM-CH在10、50、100、200μg／ml作用KFB48、72h后，对KFB增殖有明显抑制作用（P〈0．05）。200μg／ml作用24、48、72h后，对KFB增殖抑制作用与曲安萘德组比较差异无统计学意义（P〉0．05）。CM-CH在10、50、100、200μg／ml对KFB作用48h后，能显著抑制该细胞胶原的合成（P〈0．01）。100、200μg／ml CM-CH抑制作用与曲安萘德组比较差异无统计学意义（P〉0．05）。结论 CM-CH对体外培养的KFB增殖和胶原合成有明显抑制作用，从而提示该物质治疗瘢痕疙瘩具有潜在前景。     

角质形成细胞源IL-1α对成纤维细胞增殖及胶原分泌的影响

目的：研究角质形成细胞分泌的IL-1α对成纤维细胞生物学行为的影响。方法：组织块法培养成纤维细胞，消化法培养角质形成细胞，采用免疫组化方法检测角质形成细胞分泌的IL-1α；成纤维细胞中加入含不同浓度IL-1α抗体（0．04μg／ml，0．2μg／ml，1μg／ml）的角质形成细胞条件培养液为实验组，含DMEM的条件培养液为对照组，采用Cell counting kit-8、放免法测定成纤维细胞增殖、胶原合成。结果：细胞爬片可见大量染色阳性角质形成细胞，细胞增殖测定，各实验组吸光度（A）值与对照组比较，差异均有统计学意义（P（0．01）；随抗体浓度增高，A值减小，0．2μg／ml及1μg／ml浓度组与0．04μg／ml浓度组比较，差异有统计学意义（P〈0．01）；胶原分泌浓度测定，各实验组与对照组比较，差异均有统计学意义（P〈0．01）：随抗体浓度及胶原浓度增高，0．2μg／ml及1μg／ml浓度组与0．04μg／ml浓度组比较，差异有统计学意义（P（0．01）。结论：正常角质形成细胞分泌大量IL-1α，可促进成纤维细胞增殖，抑制胶原分泌。     

白鲜皮提取物拮抗内毒素/脂多糖的实验观察

目的 了解白鲜皮提取物2（DPR-2）对内毒素／脂多糖（LPS）的体外拮抗活性。方法 采用动态比浊法鲎试验定量检测DPR-2对LPS（0．1μg／L）的中和作用，激光共聚焦扫描显微镜观察不同浓度DPR-2（0、8、0、16．0、32．0、64．0mg／L）对异硫氰酸荧光素-LPS（FITC-LPS，100．0μg／L）与小鼠单核细胞株RAW264、7结合力的影响，用荧光定量反转录．聚合酶链反应（RT-PCR）法检测以上浓度DPR-2对LPS（100．0μg／L）刺激的RAW264．7细胞肿瘤坏死因子α（TNF-α）和白细胞介素6（IL-6）mRNA表达的影响。结果 DPR-2对LPS具有一定的中和作用（P〈0．05或P〈0．01）；浓度为32．0、64．0mg／L时可显著抑制FITC-LPS与RAW264．7细胞结合（P〈0.01）；对LPS刺激的小鼠RAW264．7细胞TNF-α和IL-6mRNA的表达有抑制作用，该作用具有一定的剂量-效应关系。结论 DPR-2可通过中和LPS的作用阻断与RAW264．7细胞膜受体结合，从而抑制LPS介导的细胞活化。     

异烟肼对大鼠成骨细胞影响的观察

目的：研究异烟肼（isoniazid，INH）对大鼠成骨细胞（osteoblasts，OB）增殖、碱性磷酸酶（Alkaline phosphatase，ALP）活性和Ⅰ型胶原合成的影响。方法：分离、培养新生SD大鼠头盖骨OB，分别加入不同浓度的INH（1、10、20、40、60、100、1000μg／ml）共同培养96h，对照组不加INH，分别采用四唑盐（MTT）比色实验、ALP活性测定法和^3H—Proline（^3氢-脯氨酸）法测定OB增殖、ALP活性和Ⅰ型胶原合成的情况。结果：与对照组比较，INH在60μg／ml即可抑制大鼠OB增殖（P〈0．05），40μg／ml时大鼠成骨细胞ALP活性明显下降（P〈0．05）．20μg/ml时大鼠成骨细胞Ⅰ型胶原合成（P〈0．05）明品减少，且都随浓度增加抑制作用加强。结论：INH存较低浓度时对OB增殖、ALP活性和Ⅰ型胶原合成即有抑制作用，故在骨结核治疗中应该严格控制药物剂量．特别是在局部用药时。     

三七总甙对人增生性瘢痕成纤维细胞转分化的作用

目的 观察三七总甙（PNS）对人增生性瘢痕成纤维细胞（HSF）向肌成纤维细胞转分化的作用，探讨PNS抗瘢痕纤维化的机制。方法 体外培养HSF，采用不同浓度的PNS进行干预，根据细胞培养所加PNS浓度分为400μg／ml组、800μg／ml组及空白对照组（不加PNS）。采用细胞三维培养法检测HSF凝胶收缩情况，计算其收缩指数；免疫细胞化学染色法检测HSF中“平滑肌肌动蛋白（α-SMA）的表达；流式细胞仪检测HSF中α-SMA阳性细胞率。结果 400μg／ml、800μg／ml组各时相点的胶原凝胶块收缩程度明显减轻，其收缩指数均小于空白对照组（P〈0．05或P〈0．01）。HSF中α-SMA阳性表达颗粒在细胞质内呈弥漫性分布；空白对照组HSF中α-SMA的阳性表达明显强于400μg／ml、800μg／ml组。400μg／ml、800μg／ml组α-SMA的阳性细胞率（31．52％、24．28％）均明显低于空白对照组（45．74％，P〈0．05）。400l,Lg／ml、800μg／ml组α-SMA的阳性细胞染色强度积分均明显低于空白对照组（P〈0．05或P〈0．01）。结论 PNS能够抑制HSF向肌成纤维细胞的转分化，具有体外抗瘢痕纤维化的作用。     

瑞芬太尼和异丙酚对健康成人静脉血中性粒细胞CD11b表达的影响

目的探讨瑞芬太尼和异丙酚对健康成人静脉血中性粒细胞（PMNs）CD11b表达的影响。方法取成人静脉血，采用正交实验设计确立实验因素为瑞芬太尼和异丙酚；实验水平数为5水平，即瑞芬太尼空白对照、溶媒（甘氨酸）对照、5ng／ml、50ng／ml、500ng／ml和异丙酚空白对照、溶媒（脂肪乳）对照、5μg／ml、50μg／ml、500／μg／ml，用正交表L25（5^6），观察药物对静息状态和脂多糖（LPS）激活状态PMNs下CD11b表达的影响，对激活状态的PMNs根据用药时机的不同又分为预防性用药和治疗性用药。预防性用药加入药物后1h用终浓度为1μg／ml的LPS进行刺激；治疗性用药在LPS刺激后1h加药。各标本均放入37℃、95％的空气-5％的CO2培养箱中孵育3h，其间每隔1h混匀1次。用流式细胞仪测定PMNs CD11b表达。结果瑞芬太尼和异丙酚对静息状态PMNs CD11b的表达无影响。预防性用药对PMNs CD11b表达的比较：与空白对照比较，5、50、500ng／ml瑞芬太尼可上调激活状态PMNs CD11b表达（P〈0．05或0．01）；与甘氨酸对照比较，50、500ng／ml瑞芬太尼可上调激活状态PMNs CD11b表达（P〈0．05和0．01）；异丙酚对激活状态PMNs CD11b表达无影响。治疗性用药对PMNs CD11b表达的比较：与空白对照和甘氨酸对照比较，500ng／ml瑞芬太尼可上调激活状态PMNs CD11b表达（P〈0．01）；与空白对照比较，50ng／ml异丙酚可上调激活状态PMNs CD11b表达（P〈0．05）。结论瑞芬太尼和异丙酚对PMNs的CD11b表达的影响可能与PMNs所处的状态、用药剂量以及用药时机有关。     

异丙酚对脂多糖诱导大鼠腹腔巨噬细胞Toll样受体-4 mRNA表达的影响

目的 观察异丙酚对脂多糖（LPS）诱导大鼠腹腔巨噬细胞Toll样受体-4（TLR-4）mRNA表达的影响，探讨异丙酚抑制LPS诱导白细胞介素-6（IL-6）和肿瘤坏死因子-α（TNF—α）产生的机制。方法 雄性Wistar大鼠32只，处死后分离腹腔巨噬细胞，随机分为4组（n=8）：A组（阴性对照组）；B组LPS（终浓度为1μg／ml）／加入巨噬细胞中；C组LPS（终浓度为1μg／ml）＋异丙酚（终浓度为1μg／ml）加入巨噬细胞中；D组LPS（终浓度为1μg／ml）＋异丙酚（终浓度为5μg／ml）加入巨噬细胞中。细胞培养12h后。用ELISA方法检测培养上清液中IL-6、TNF-α的浓度，用RT-PCR方法检测TLR-4mRNA的表达水平。结果 与A组相比，B组IL-6、TNF-α和TLR-4m RNA水平均增加，C组IL-6、TLR-4m RNA水平升高（P〈0．01）；与B组相比，C组、D组IL-6、TNF-α和TLR-4m RNA水平降低（P〈0．05或〈0．01）。结论 异丙酚通过下调TLR-4m RNA的表达水平，从而一定程度上抑制了LPS诱导大鼠腹腔巨噬细胞，TNF-α和IL-6的产生。     

当归挥发油对人脐静脉内皮细胞增殖、凋亡及Ⅲ型胶原合成的影响

目的探讨当归挥发油对人脐静脉内皮细胞增殖、凋亡和胶原合成的影响。方法体外培养人脐静脉内皮细胞，用噻唑蓝比色法检测细胞增殖活性，用流式细胞术分析细胞周期及凋亡，用放射免疫法测定胶原合成。结果低浓度（≤4mg／L）当归挥发油促进细胞增殖（P〈0．05），降低G0/G1期细胞且增加S期细胞（P〈0．05），降低凋亡率（P〈0．05），而高浓度（≥16mg／L）时抑制增殖（P〈0．05），增加G0/G1期细胞且减少S期细胞（P〈0．05），增加凋亡率（P〈0．05）。当归挥发油呈剂量和时问依赖性抑制细胞合成胶原（P〈0．05或0．01）。结论当归挥发油对人脐静脉内皮细胞的增殖呈低浓度刺激高浓度抑制的双向调节作用，但对胶原合成呈抑制效应。     

肝素对大鼠Ⅱ度烧伤创面愈合的影响

目的　研究肝素对大鼠 度烧伤创面愈合的影响。方法　 2 0只 SD大鼠随机分为两组 ,制成2 0 %面积深 度烧伤 ,实验组采用肝素 10 0 U /kg加生理盐水至 1ml皮下注射 ;对照组采用生理盐水 1ml皮下注射 ,每天一次直至创面完全愈合。从大体观察创面愈合天数及全身有无出血现象 ,光镜观察肉芽组织及胶原纤维生长情况 ,电镜观察成纤维细胞生长情况。结果　大鼠全部成活。实验组创面愈合时间为 (2 2 .8± 1.87)天 ,对照组为(2 6 .2± 2 .82 )天 ,实验组创面愈合所需时间明显少于对照组 (P<0 .0 0 5 )。光镜观察发现实验组肉芽组织及胶原纤维生长明显优于对照组。电镜观察发现实验组成纤维细胞生长优于对照组。结论　肝素皮下注射能加速创面愈合。     

Celosia argentea Linn. leaf extract improves wound healing in a rat burn wound model

Celosia argentea (CA) is used in traditional medicine for sores, ulcers, and skin eruptions. The present study was aimed at investigating the healing efficacy of CA extract in an ointment formulated (10 % w/w) as an alcohol extract of CA using a rat burn wound model. Wound closure occurred earlier in the treated rats (15 days vs. 30 in the untreated group; p < 0.05). Granulation tissue collected on every fifth day of healing showed an increase in collagen and hexosamine content at a faster rate in the treated wounds. This correlated with the accelerated wound closure observed in the treated groups. To probe the cellular basis of this effect, we investigated the effect of this extract on two major cellular responses; cell proliferation and cell motility, in two key cell lineages, fibroblasts and keratinocytes. CA was not toxic at concentrations of < 3 microg/ml in fibroblasts and < 30 microg/ml in keratinocytes. The alcohol extract promoted cell motility and proliferation of primary dermal fibroblasts at 0.1-1.0 microg/ml but did not alter these responses in primary keratinocytes. In an initial examination of molecular mechanisms, we found that the CA extract did not alter fibroblast and keratinocyte responses to the wound repair-associated epidermal growth factor receptor ligands. In short, we demonstrate a salutary action of the CA extract on wound healing, and suggest that this may be due to mitogenic and motogenic promotion of dermal fibroblasts.     

辐射对伤口液调节成纤维细胞特性的影响和苯妥英钠的应用

目的研究全身辐射后伤口液对成纤维细胞（ＦＢＳ）特性的调节作用的变化及苯妥英钠的作用。方法采用大鼠背部置入聚乙烯醇海绵的切口伤模型,收集伤口液和ＦＢＳ,并测定ＦＢＳ的增殖和胶原合成特性。结果在伤后５～８天,伤口液刺激ＦＢＳ增殖和胶原合成的作用最强,６Ｇｙ全身辐射后,伤口液刺激ＦＢＳ增殖和胶原合成的作用都明显降低,而苯妥英钠对非辐射组和辐射组伤口液刺激ＦＢＳ增殖和胶原合成的作用都有明显的提高。结论全身辐射后,伤口局部环境的改变不利于组织细胞的修复;苯妥英钠能加强伤口液刺激ＦＢＳ增殖和胶原合成的作用,有利于创伤愈合。     

In vitro studies on the antioxidant and growth stimulatory activities of a polyphenolic extract from Cudrania cochinchinensis used in the treatment of wounds in Vietnam

The leaves of Cudrania cochinchinensis, a Vietnamese folk remedy, have been suggested as a beneficial agent for wound healing. Animal studies and clinical observations in Vietnam have shown positive wound healing activity. We studied the effects of a polyphenolic extract from the plant on the proliferation of cells in culture and their response to oxidative damage by hydrogen peroxide. Fibroblasts were incubated with different concentrations of the extract in 0.4% fetal calf serum, and proliferation was monitored by a colorimetric assay. Cell damage was induced by exposure to hydrogen peroxide 7 x 10(-5) mol/L for 3 hours. The same colorimetric assay was used to assess cell damage and the protective effect of the extract against oxidative damage. The extract at low concentrations (0.1 to 5 microg/ml) had a stimulatory effect on fibroblast growth. The effect was significant by 7 days after the addition of the extract and was strongest at a concentration of 1 microg/ml of extract (p< or = 0.01). The extract at concentrations of 5 or 50 microg/ml protected fibroblasts and endothelial cells against hydrogen peroxide-induced damage. Pretreatment with the extract or exposure to extract simultaneously with hydrogen peroxide gave only partial protection against oxidative damage, whereas a combination of the two treatments gave complete protection (p< or = 0.005). Stimulation of fibroblast proliferation and protection of cells against destruction by inflammatory mediators may be ways in which the polyphenolic substances from the plant, Cudrania cochinchinensis, contribute to wound healing.     

Basic fibroblast growth factor in an artificial dermis promotes apoptosis and inhibits expression of α-smooth muscle actin, leading to reduction of wound contraction

To clarify the mechanisms underlying declines in wound contraction caused by basic fibroblast growth factor (bFGF) and the role of autologous fibroblasts in modulating wound healing, we have examined the expression of alpha-smooth muscle actin (alpha-SMA) and apoptosis in a model of wound healing using collagen sponges with and without bFGF (1 microg) and/or fibroblasts (1 x 10(6) cells/cm(2)) applied to experimentally produced full-thickness skin wounds in rats (n=10 for each group). At 7 days postoperatively, wounds filled with a fibroblast-seeded collagen sponge (fibroblast-seeded group) displayed a greater area of collagen sponge and a smaller area of fibroblasts compared with control wounds filled with collagen sponge alone (control group). Therefore, seeding of fibroblasts in the dermal substitute might retard degradation of the collagen sponge, inhibiting fibroblast infiltration into the substitute. By day 14, wounds filled with bFGF-treated collagen sponge without fibroblast seeding (bFGF group) displayed decreased alpha-SMA expression and significantly increased apoptosis compared with other wounds. Double staining revealed that apoptosis in alpha-SMA-positive fibroblastic cells was significantly increased in the bFGF group, suggesting that bFGF treatment is a potent stimulator of myofibroblast apoptosis. Furthermore, morphometric analysis demonstrated the significant decrease in the level of wound contraction and the degree of mature collagen bundle formation in the bFGF group by day 42. The bFGF group also showed increased bFGF expression in macrophages by day 28. These results suggest that bFGF administration to an artificial dermis promotes apoptosis of alpha-SMA-positive fibroblastic cells and inhibits alpha-SMA expression in the treated wound, thus reducing wound contraction.     

瘦素对体外大鼠成纤维细胞增殖与胶原合成的影响

目的　研究瘦素对体外培养大鼠成纤维细胞 (fibroblast,FB)增殖与胶原合成的影响 ,以阐明 FB介导瘦素在大鼠皮肤创伤愈合中的促进作用。　方法　体外培养乳鼠真皮 FB,通过 MTT比色分析法、3H-胸腺嘧啶核苷(3H- Td R)和 3H-脯氨酸 (3H- Pro)掺入法观察不同浓度的瘦素 ,分别为 0、10、5 0、10 0、2 0 0及 4 0 0 ng/ ml对其增殖和胶原合成的影响。　结果　瘦素剂量在 4 0 0 ng/ ml以下时 ,随瘦素剂量增加明显增加了体外培养大鼠 FB MTT的光密度值和 3H- Td R的掺入量。3H- Pro的掺入量随瘦素剂量增加基本呈增大趋势。 2 0 0、4 0 0 ng/ ml剂量组的3H- Td R掺入量 379±10 1cpm、32 6± 33cpm,与对照组 2 19± 5 6 cpm比较有统计学差异 (P<0 .0 5 ) ;且 2 0 0、4 0 0 ng/ ml剂量组的 MTT吸光度(A)值 0 .0 82± 0 .0 13、0 .0 91± 0 .0 18与对照组 0 .0 6 3± 0 .0 10比较有统计学差异 (P<0 .0 5 ) ;2 0 0、4 0 0 ng/ ml剂量组的 3H- Pro掺入量 911± 5 5 cpm、10 72± 2 5 9cpm,与对照组 6 79± 176 cpm比较有统计学差异 (P<0 .0 5 )。　结论　瘦素促进了 FB的增殖和胶原蛋白的合成 ,这可能是瘦素发挥促进大鼠皮肤愈合作用的途径之一。     

The role of iNOS in wound healing

BACKGROUND: We have previously shown that the blockade of nitric oxide (NO) synthesis impairs wound healing, in particular collagen synthesis. Conversely, impaired wound healing is accompanied by decreased wound NO synthesis. Fibroblast collagen synthesis, proliferation, and fibroblast-mediated matrix contraction are critical to wound healing. We examined the wound healing-related phenotypic changes that are induced by the loss of inducible nitric oxide synthase (iNOS) gene function in fibroblasts. METHODS: Dermal fibroblasts were obtained from 8- to 12-week-old iNOS--knock out (KO; C57BL/Ai-[KO] Nos2 N5) and wild type mice by an explant technique and used after 1 to 3 passages. Proliferation ([(3)H]-thymidine incorporation) and collagen synthesis ([(3)H]-proline incorporation into collagenase-sensitive protein) were studied after stimulation with 10% fetal bovine serum. Matrix remodeling was assessed by the measurement of the contraction of fibroblast-populated collagen lattices. RESULTS: iNOS-KO fibroblasts proliferated more slowly, synthesized less collagen, and contracted fibroblast-populated collagen lattices more slowly than wild-type fibroblast. Collagen synthesis was restored to normal in KO fibroblasts in response to NO donors (s-nitroso-N-acetylpenicillamine). CONCLUSIONS: iNOS deficiency causes significant impairment in wound healing-related properties of fibroblasts, which suggests that NO plays an important role in wound healing.     

单核巨噬细胞集落刺激因子对人皮肤成纤维细胞增殖及胶原合成的影响

目的：研究单核巨噬细胞集落刺激因子（granulocyte/macrophage colony-stimulating factor,GMCSF）对人皮肤成纤维细胞增殖及胶原合成的影响,探讨其促进创面愈合的机制并为临床准确定量应用该因子促进创面愈合提供理论依据。方法：分别应用浓度为0、25、50、75、100、150ng/mlGMCSF培养液孵育离体培养的人皮肤成纤维细胞,作用24h后四甲基偶氮唑盐比色法（MTT）检测细胞的活性。选择最适浓度GMCSF干预细胞,用流式细胞仪检测成纤维细胞的周期变化;应用ELISA检测上清液中Ⅰ、Ⅲ型胶原合成情况。结果：GMCSF在浓度为25～100ng/ml之间对人皮肤成纤维细胞有明显的促增殖作用,其中以50/ml最为显著;成纤维细胞在最适浓度GMCSF干预24h后,细胞大多处于DNA合成前期和合成期;与空白组比较,GMCSF组Ⅰ、Ⅲ型胶原分泌明显增加（P〈0.01）,且Ⅰ、Ⅲ型胶原比值下降（P〈0.01）。结论：GMCSF在浓度为25～100ng/ml对人皮肤成纤维细胞有明显的促增殖作用,且能刺激成纤维细胞合成大量Ⅰ、Ⅲ型胶原,这可能是其加速创面愈合的机制之一。     

Comparison of human umbilical cord blood‐derived mesenchymal stem cells with healthy fibroblasts on wound‐healing activity of diabetic fibroblasts

Various types of skin substitutes composed of fibroblasts and/or keratinocytes have been used for the treatment of diabetic ulcers. However, the effects have generally not been very dramatic. Recently, human umbilical cord blood‐derived mesenchymal stromal cells (hUCB‐MSCs) have been commercialised for cartilage repair as a first cell therapy product using allogeneic stem cells. In a previous pilot study, we reported that hUCB‐MSCs have a superior wound‐healing capability compared with fibroblasts. The present study was designed to compare the treatment effect of hUCB‐MSCs with that of fibroblasts on the diabetic wound healing in vitro. Diabetic fibroblasts were cocultured with healthy fibroblasts or hUCB‐MSCs. Five groups were evaluated: group I, diabetic fibroblasts without coculture; groups II and III, diabetic fibroblasts cocultured with healthy fibroblasts or hUCB‐MSCs; and groups IV and V, no cell cocultured with healthy fibroblasts or hUCB‐MSCs. After a 3‐day incubation, cell proliferation, collagen synthesis levels and glycosaminoglycan levels, which are the major contributing factors in wound healing, were measured. As a result, a hUCB‐MSC‐treated group showed higher cell proliferation, collagen synthesis and glycosaminoglycan level than a fibroblast‐treated group. In particular, there were significant statistical differences in collagen synthesis and glycosaminoglycan levels (P = 0·029 and P = 0·019, respectively). In conclusion, these results demonstrate that hUCB‐MSCs may have a superior effect to fibroblasts in stimulating diabetic wound healing.     

Glucan stimulates human dermal fibroblast collagen biosynthesis through a nuclear factor-1 dependent mechanism

Glucan, an immunomodulator, has been reported to increase collagen deposition and tensile strength in experimental models of wound repair. Previous data suggest that glucan modulates wound healing via an indirect mechanism in which macrophages are stimulated to release growth factors and cytokines. However, recent data have shown the presence of glucan receptors on normal human dermal fibroblasts, suggesting that glucans may be able to directly stimulate fibroblast collagen biosynthesis. To test this hypothesis, we examined the effect of glucan on collagen biosynthesis in normal human dermal fibroblasts. We assessed nuclear factor-1 (NF-1) activation, procollagen mRNA expression, collagen biosynthesis, and whether there was a causal link between glucan treatment, NF-1 activation, and collagen expression. Glucan (1 microg/ml) increased NF-1 binding activity by 46% (8 hours), 64% (24 hours), 215% (36 hours), and 119% (48 hours) in cultured normal human dermal fibroblasts. Alpha 1(I) and alpha1 (III) procollagen mRNA were increased in glucan-treated normal human dermal fibroblasts when compared with the untreated fibroblasts. Collagen synthesis was increased at 24 hours and 48 hours following glucan treatment of normal human dermal fibroblasts. Down-regulation of NF-1 by pentifylline inhibited glucan-induced procollagen mRNA expression. These data indicate that glucan can directly stimulate human fibroblast collagen biosynthesis through an NF-1-dependent mechanism.