[关键词]
[摘要]
目的 探究苦豆子总碱(TAS)凝胶对糖尿病大鼠伤口愈合的作用机制。方法 (1)采用链脲佐菌素(STZ, 60 mg·kg-1 )腹腔注射建立糖尿病大鼠模型,切除背部全层皮肤复制糖尿病大鼠全层皮肤缺损模型。将 40 只大 鼠随机分为对照组、模型组、TAS 低剂量组(1% TAS 凝胶)、TAS 高剂量组(2% TAS 凝胶)、阳性组(牛碱性成 纤维细胞生长因子凝胶),每组 8 只。TAS 低、高剂量组与阳性组涂抹对应药物凝胶,对照组和模型组涂抹等 量空白凝胶,每天 1 次,连续给药 12 d。采用 HE 染色观察大鼠伤口组织病理变化;Masson 染色和免疫组化 法检测大鼠伤口皮肤组织胶原沉积和血管新生;TUNEL 染色检测大鼠伤口组织细胞凋亡;免疫荧光染色法测 定大鼠伤口组织 F4/80+ 、CD86+ 、CD206+ 细胞表达;ELISA 法检测大鼠伤口组织肿瘤坏死因子 α(TNF-α)、转 化生长因子 β1(TGF-β1)、白细胞介素(IL)1β、IL-10 的表达水平。(2)采用脂多糖(LPS)、干扰素 γ(IFN-γ) 和 IL-4 诱导 THP-1 细胞 M1/M2 表型极化,将 THP-1 细胞分为 M0 组、M1 组、M2 组、TAS 低剂量组(M1/ M2+10 µg·mL-1 TAS)、TAS 高剂量组(M1/M2+20 µg·mL-1 TAS)、糖酵解抑制剂(2-DG)组(M1+2 mmol·L-1 2-DG)。 给药 48 h 后,采用流式细胞仪检测细胞 CD86+ 百分比、CD206+ 百分比。采用乳酸试剂盒检测 THP-1 细胞 M1 极化下乳酸含量;Western Blot 法检测细胞己糖激酶 2(HK2)和葡萄糖转运蛋白 1(Glut1)的蛋白表达。结果 (1)与对照组比较,模型组大鼠伤口上皮未闭合,出现组织结构紊乱、大量炎性细胞浸润、新生血管结构不完 整等现象,胶原蛋白含量、新生血管数减少(P<0.01);与模型组比较,TAS 给药组大鼠伤口上皮闭合,组织 结构紊乱、大量炎性细胞浸润、新生血管结构不完整等现象减少,胶原蛋白含量、新生血管数明显增加(P< 0.05,P<0.01)。与对照组比较,模型组大鼠伤口未愈合率及伤口组织 TUNEL 阳性细胞百分比、CD86+ (/ F4/ 80+ )百分比增加(P<0.01),TNF-α 和 IL-1β 水平升高(P<0.01);CD206+ (/ F4/80+ )百分比减少(P<0.01), IL-10 和 TGF-β1 水平降低(P<0.05,P<0.01)。与模型组比较,TAS 给药组伤口组织 TUNEL 阳性细胞百分 比、CD86+ (/ F4/80+ )百分比减少(P<0.01),TNF-α 和 IL-1β 水平降低(P<0.05,P<0.01),CD206+ (/ F4/80+ )百 分比增加(P<0.01),IL-10、TGF-β1 水平升高(P<0.05,P<0.01)。(2)与 M0 组比较,M1 组细胞 CD86+ 百分 比、乳酸水平升高(P<0.01),HK2 和 Glut1 蛋白表达上调(P<0.01),M2 组 CD206+ 百分比增加(P<0.01)。与 M2 组比较,TAS 给药组细胞 CD206+ 百分比减少(P<0.01);与 M1 组比较,TAS 给药组与 2-DG 组细胞 CD86+ 百分比减少(P<0.01),且 TAS 给药组乳酸水平与 HK2、Glut1 蛋白表达降低(P<0.05,P<0.01)。结论 TAS 凝胶能够抑制糖尿病大鼠炎症反应,促进伤口组织血管新生与胶原沉积,加快糖尿病伤口愈合,其抗炎机制与 抑制糖酵解代谢,调控巨噬细胞 M1/M2 表型极化有关。
[Key word]
[Abstract]
Objective To investigate the mechanism of total alkaloids of Sophora Alopecuroides (TAS) gel in promoting wound healing in diabetic rats. Methods (1) A diabetic rat model was established by intraperitoneal injection of Streptozotocin (STZ,60 mg·kg-1 ),and a full-thickness skin defect model was created by excising the dorsal skin. Forty rats were randomly divided into a control group,a model group,a low-dose TAS group (1% TAS gel),a high-dose TAS group (2% TAS gel),and a positive control group (recombinant bovine basic fibroblast growth factor gel),with eight rats in each group. The low- and high-dose TAS groups and the positive control group were treated with the corresponding gels,while the control and model groups were treated with blank gel,once daily for 12 days. HE staining was used to observe pathological changes in wound tissues; Masson staining and immunohistochemistry were used to detect collagen deposition and angiogenesis in wound tissues;TUNEL staining was used to detect apoptosis in wound tissues;immunofluorescence staining was used to measure the expressions of F4/80+ , CD86+ ,and CD206+ cells in wound tissues;ELISA was used to detect the levels of tumor necrosis factor-α (TNF-α), transforming growth factor- β1 (TGF-β1),interleukin (IL)-1β,and IL-10 in wound tissues. (2) THP-1 cells were polarized into M1/M2 phenotypes using lipopolysaccharide (LPS) /interferon-γ (IFN-γ) and IL-4. The cells were divided into an M0 group,an M1 group,an M2 group,a low-dose TAS group (M1/M2 + 10 µg·mL-1 TAS),a high-dose TAS group (M1/M2 + 20 µg·mL-1 TAS),and a glycolysis inhibitor(2-DG)group (M1 + 2 mmol·L-1 2- DG). After 48 hours of treatment,flow cytometry was used to detect the percentages of CD86+ and CD206+ cells. A lactate assay kit was used to measure lactate levels in M1-polarized THP-1 cells;Western Blot was used to detect the protein expressions of hexokinase 2 (HK2) and glucose transporter 1 (Glut1). Results (1)Compared with the control group,the model group showed unclosed wound epithelium,disordered tissue structure,massive inflammatory cell infiltration,incomplete neovascularization,reduced collagen content,and decreased neovascularization (P<0.01). Compared with the model group,the TAS-treated groups showed closed wound epithelium,reduced disordered tissue structure, inflammatory cell infiltration, and incomplete neovascularization, and significantly increased collagen content and neovascularization (P<0.01). Compared with the control group,the model group showed increased wound non-healing rate,TUNEL-positive cell percentage,and CD86+ (/ F4/80+ ) percentage (P<0.01),elevated TNF-α and IL-1β levels (P<0.01),decreased CD206+ (/ F4/80+ ) percentage (P<0.01),and reduced IL-10 and TGF-β1 levels (P<0.05, P<0.01). Compared with the model group, the TAS-treated groups showed reduced TUNELpositive cell percentage and CD86+ (/ F4/80+ ) percentage (P<0.01), decreased TNF- α and IL-1β levels (P< 0.05,P<0.01),increased CD206+ (/ F4/80+ ) percentage (P<0.01),and elevated IL-10 and TGF-β1 levels (P< 0.05,P<0.01). (2) Compared with the M0 group,the M1 group showed increased CD86+ percentage and lactate levels (P<0.01),upregulated HK2 and Glut1 protein expression (P<0.01),and the M2 group showed increased CD206+ percentage (P<0.01). Compared with the M2 group, the TAS-treated group showed reduced CD206+ percentage (P<0.01); compared with the M1 group, the TAS-treated and 2-DG groups showed reduced CD86+ percentage (P<0.01), and the TAS-treated group showed decreased lactate levels and HK2 and Glut1 protein expression (P<0.05). Conclusion TAS gel can inhibit inflammatory responses,promote angiogenesis and collagen deposition in wound tissues,and accelerate diabetic wound healing. Its anti-inflammatory mechanism is related to the inhibition of glycolysis metabolism and regulation of macrophage M1/M2 phenotypic polarization.
[中图分类号]
R285.5;R587.1
[基金项目]
国家自然科学基金地区项目(82160777,82260803)