基于CREB3L1探讨矾冰纳米乳对兔耳增生性瘢痕模型相关蛋白及炎症因子的影响

Based on CREB3L1 to Explore Effect of Alum-borneol Nanoemulsion on Related Protein and Inflammatory Factors in Rabbit Ear Hypertrophic Scarring Model

目的观察矾冰纳米乳对兔耳增生性瘢痕组织环腺苷酸应答元件结合蛋白3样1(CREB3L1)及炎症损伤的影响,探讨其预防增生性瘢痕的作用机制。方法将30只新西兰大耳白兔随机分为空白组、模型组、积雪草苷组及矾冰纳米乳低、中、高剂量组(8.15、16.3、32.6 mg·mL^(-1))。采用热力烫伤法进行造模,深Ⅱ度烧伤造模成功后第14天给予相应药物外用,空白组、模型组外用等量生理盐水,每日2次,连续给药至第35天。苏木素-伊红(HE)染色观察兔耳瘢痕组织病理学改变;马松(Masson)染色观察瘢痕组织胶原沉积情况;免疫荧光双标法检测兔耳瘢痕组织CREB3L1/α-平滑肌肌动蛋白(α-SMA)共表达情况;酶联免疫吸附测定法(ELISA)检测瘢痕组织白细胞介素6(IL-6)、白细胞介素10(IL-10)等炎性因子表达;实时荧光定量聚合酶链式反应(Real-time PCR)检测CREB3L1、Ⅰ型胶原蛋白(COL-Ⅰ)、Ⅲ型胶原蛋白(COL-Ⅲ)、α-SMA mRNA表达;蛋白免疫印迹法(Western Bolt)检测CREB3L1、COL-Ⅰ、COL-Ⅲ、α-SMA的蛋白表达情况。结果与空白组比较,模型组瘢痕增生指数明显升高(P<0.01);病理学改变包括真皮层增厚,形成致密的网状纤维,伴见炎症细胞浸润;Masson染色可见真皮层增厚,蓝染的胶原纤维大量沉积排列紊乱;免疫荧光双标结果显示,瘢痕组织中CREB3L1阳性表达增加,α-SMA阳性表达增加,IL-6含量明显升高(P<0.01),IL-10含量明显降低(P<0.01),兔耳瘢痕组织中的CREB3L1、COL-Ⅰ、COL-Ⅲ、α-SMA mRNA相对表达量明显增加(P<0.01),CREB3L1、COL-Ⅰ、COL-Ⅲ、α-SMA蛋白的表达明显增加(P<0.01)。与模型组比较,矾冰纳米乳中、高剂量组及积雪草苷组治疗后瘢痕增生指数均明显下降(P<0.05,P<0.01),病理改变可见真皮层变薄,炎性细胞均有不同程度减少,蓝染的胶原纤维减少,免疫荧光双染可见瘢痕组织中CREB3L1阳性表达降低,α-SMA阳性表达降低,IL-6含量明显降低(P<0.01),IL-10含量明显升高(P<0.01),矾冰纳米乳中、高剂量组和积雪草苷组均能够明显下调CREB3L1、COL-Ⅰ、COL-Ⅲ、α-SMA mRNA的表达(均P<0.01),降低CREB3L1、COL-Ⅰ、COL-Ⅲ、α-SMA蛋白的表达(P<0.05,P<0.01)。结论矾冰纳米乳能够通过调节CREB3L1及相关纤维化蛋白的表达,降低炎症水平,从而预防增生性瘢痕形成,丰富了中医“既病防变”“治未病”思想的科学内涵。

Objective To investigate the mechanism of the preventive effect of alum-borneol nanoemulsion on hypertrophic scars by observing its effect on cAMP-response element-binding protein 3-like 1(CREB3L1)and inflammatory damage in hypertrophic scar tissues of rabbit ear.Methods Thirty New Zealand big-eared white rabbits were randomly divided into blank group,model group,alum-borneol nanoemulsion low-,medium-,and high dose groups(8.15,16.3,and 32.6 mg·mL^(-1)),and asiaticoside group.The animal model was established by thermal injury.Topical application of appropriate drugs was given on the 14th day after successful modeling of deep II-degree burns.Equal amounts of saline were applied externally to the blank and model groups twice daily and administered continuously until the 35th day.Histopathological changes in rabbit ear scar tissue were observed by hematoxylin-eosin(HE)staining.Masson staining was used for collagen deposition in scar tissue.Coexpression of CREB3L1/alpha-smooth muscle actin(α-SMA)in rabbit ear scar tissue was detected by immunofluorescence double-labeling assay.Enzyme-linked immunosorbent assay(ELISA)was applied for the detection of interleukin-6(IL-6)and interleukin-10(IL-10)in scar tissue.Real-time fluorescence quantitative polymerase chain reaction(Real-time PCR)was applied for the detection of CREB3L1,Collagen Type I(COL-Ⅰ),Collagen TypeⅢ(COL-III),andα-SMA mRNA expression.Protein expression of CREB3L1,COL-Ⅰ,COL-Ⅲ,andα-SMA was detected by protein immunoblotting analysis(Western Bolt).Results Compared with the blank group,the scar proliferation index of the model group was significantly increased(P<0.01).Pathologic changes including the thickening of the dermis,the formation of dense reticular fibers,and accompaniment of inflammatory cell infiltration were observed.Masson staining reveals thickening of the dermis,disordered arrangement and large deposits of blue stained collagen fibers.Double-labeling immunofluorescence results showed that positive expression of CREB3L1 andα-SMA in scar tissue increased.IL-6 levels were significantly increased(P<0.01),while IL-10 levels were significantly decreased(P<0.01).The relative mRNA expression of CREB3L1,COL-Ⅰ,COL-Ⅲ,andα-SMA in the scar tissue of rabbit ear was significantly increased(P<0.01).The protein expression of CREB3L1,COL-Ⅰ,COLⅢ,andα-SMA was significantly increased(P<0.01).Compared with the model group,the scar proliferation index was significantly decreased after the treatment of medium,high-dose of alum-borneol nanoemulsion and asiaticoside(P<0.01,P<0.05,P<0.01).Pathologic changes including the thinning of the dermis,as well as varying degrees of reduction of inflammatory cells and blue-stained collagen fibers were found.Double-labeling immunofluorescence showed positive expression of CREB3L1 andα-SMA in scar tissue decreased.IL-6 levels significantly reduced(P<0.01),while IL-10 levels significantly raised(P<0.01).The alum-borneol nanoemulsion medium-,high-dose and asiaticoside groups could significantly down-regulate the mRNA expression of CREB3L1,COL-Ⅰ,COL-Ⅲ,andα-SMA(all P<0.01),and reduce the protein expression of CREB3L1,COL-Ⅰ,COL-Ⅲ,andα-SMA(P<0.05,P<0.01).Conclusion Alum-borneol nanoemulsion may prevent hyperplastic scar formation by regulating the expression of CREB3L1 and related fibrotic proteins and reducing inflammatory level,which enriches the scientific connotation of“prevention of disease from exacerbating”and“treatment of the disease before its onset”in Chinese medicine.