益气化瘀化痰方对UUO诱导的肾间质纤维化大鼠KLF15、HMGB1、NF-κB及其下游炎症因子表达的影响

目的:观察益气化瘀化痰方(YHHD)对单侧输尿管结扎(UUO)模型大鼠肾间质纤维化的作用及其可能机制。方法:48只雌性SD大鼠,随机分为假手术组、UUO模型组、替米沙坦组及YHHD低、中、高剂量组,每组8只。除假手术组外,其余各组采用UUO法建立肾间质纤维化模型。各药物干预组以相应浓度的药物灌胃,模型组及假手术组以等体积生理盐水灌胃,每日1次,连续用药12周后采集标本并处死大鼠,检测大鼠血清胱抑素C(Cys-C)和尿酸(UA)的水平,PAS染色观察肾组织形态学改变,Masson染色计算肾间质胶原纤维沉积率,realtime PCR检测肾组织Krüppel样因子15(KLF15)、高迁移率族盒蛋白1(HMGB1)、核因子κB(NF-κB)及其抑制蛋白IκB、单核细胞趋化蛋白1(MCP-1)、白细胞介素1β(IL-1β)、肿瘤坏死因子α(TNF-α)、纤维连接蛋白(FN)、I型胶原(Col I)和Ⅳ型胶原(ColⅣ)的m RNA表达水平,Western blot检测KLF15、HMGB1和NF-κB的蛋白表达,免疫组化检测MCP-1的蛋白表达。结果:与假手术组相比,模型组的胶原纤维沉积率及Cys-C水平显著升高(P0.05),KLF15的m RNA及蛋白表达显著下调(P0.05),HMGB1、NF-κB、IκB、MCP-1、IL-1β、TNF-α、FN、Col I和ColⅣ的m RNA及HMGB1、NF-κB和MCP-1的蛋白表达显著上调(P0.05);与模型组相比,YHHD中、高剂量组及替米沙坦组的胶原纤维沉积率显著降低(P0.05),且HMGB1和NF-κB的蛋白表达以及IL-1β和TNF-α的m RNA表达显著下调(P0.05);YHHD高剂量组及替米沙坦组KLF15的蛋白表达显著上调(P0.05),MCP-1的蛋白表达及FN的m RNA表达显著下调(P0.05);YHHD高剂量组KLF15的m RNA表达显著上调(P0.05),MCP-1、Col I和ColⅣ的m RNA表达明显下调(P0.05);YHHD各剂量组及替米沙坦组NF-κB和IκB的m RNA表达及Cys-C水平明显降低(P0.05)。各组间UA水平的差异无统计学显著性。结论:益气化瘀化痰方对肾间质纤维化的抑制作用呈剂量依赖性,高剂量组作用最明显;其机制可能与上调KLF15表达、抑制肾组织HMGB1和NF-κB及其下游炎症相关因子的表达有关。

Effect of Yiqi Huayu Huatan decoction on expression of KLF15, HMGB1, NF-κB and its downstream inflammatory factors in rats with UUO-induced renal interstitial fibrosis

AIM: To observe the effect of Yiqi Huayu Huatan decoction (YHHD) on unilaterral ureteral obstruction (UUO)-induced renal interstitial fibrosis in rats, and to investigate the possible mechanism. METHODS: Female SD rats (n=48) were randomly divided into sham group, model group, telmisartan group, and low-, middle-and high-dose YHHD groups, with 8 rats in each group. The UUO model rats was established by ligating left ureter. The rats in sham group and model group were treated with equal volume of normal saline, others were treated with the corresponding drugs daily. After 12 weeks, the rats were sacrificed. The serum samples were collected for determining the concentrations of cystatin C (Cys-C) and uric acid (UA). The morphological changes of the renal tissue were observed by PAS staining. The collagen fiber was observed by Masson staining. The mRNA expression of Krüppel-like factor 15 (KLF15), high-mo-bility group box protein 1 (HMGB1), nuclear factor-κB (NF-κB), IκB, monocyte chemotactic protein-1 (MCP-1), interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α), fibronectin (FN), collagen type I (Col I) and Col-Ⅳ was detected by real-time PCR. The protein expression of KLF15, HMGB1 and NF-κB was detected by Western blot. The protein expression of MCP-1 was determined by the method of immunohistochemistry. RESULTS: Compared with sham group, the deposition rate of collagen fibers and the concentration of Cys-C in model group were significantly increased (P<0.05), the mRNA and protein expression of KLF15 was significantly down-regulated (P<0.05), while the mRNA expression of HMGB1, NF-κB, IκB, MCP-1, IL-1β, TNF-α, FN, Col I and Col Ⅳ and the protein expression of HMGB1, NF-κB and MCP-1 were significantly up-regulated (P<0.05). Compared with model group, the deposition rates of collagen fibers in middle-and high-dose YHHD groups and telmisartan group were significantly decreased (P<0.05), with down-regulated protein expression of HMGB1 and NF-κB and mRNA expression of IL-1β and TNF-α (P<0.05). The protein expression of KLF15 was significantly up-regulated in high-dose YHHD group and telmisartan group (P<0.05), while the protein expression of MCP-1 and the mRNA expression of FN were significantly down-regulated (P<0.05). The mRNA expression of KLF15 was significantly up-regulated in high-dose YHHD group (P<0.05), while the mRNA expression of MCP-1, Col I and Col IV was significantly down-regulated (P<0.05). The mRNA expression of NF-κB and IκB was significantly down-regulated and the concentration of Cys-C was significantly decreased in each dose of YHHD groups and telmisartan group (P<0.05). No significant difference of UA level among the groups was observed. CONCLUSION: YHHD alleviates renal interstitial fibrosis in a dose-dependent manner, and YHHD at high dose shows the most obvious effect. The mechanism may be associated with the up-regulation of KLF15 and the down-regulation of HMGB1, NF-κB and its downstream inflammation-related factors in the renal tissue.