目的 從絲裂原活化蛋白激酶(MAPK)/胞外信號(hào)調(diào)節(jié)激酶1/2(ERK1/2)/c-Jun氨基末端激酶1/2(JNK1/2)通路探究染料木黃酮對(duì)蕁麻疹大鼠的保護(hù)機(jī)制。方法SD大鼠隨機(jī)分為對(duì)照組、模型組、染料木黃酮低、高劑量(150、300 mg/kg)組,MAPK激活劑(茴香霉素)組、染料木黃酮+茴香霉素組,每組12只。通過卵蛋白血清致敏誘導(dǎo)建立大鼠慢性蕁麻疹模型。觀察大鼠搔抓癥狀;ELISA法檢測(cè)血清免疫球蛋白E抗體(IgE)及炎癥介質(zhì)如組胺、白三烯、前列腺素(PGD2)、5-羥色胺(5-HT)水平;伊文思藍(lán)染色觀察血管通透性改變;蘇木精-伊紅(HE)染色觀察藍(lán)斑皮膚組織病理變化;取腹腔肥大細(xì)胞計(jì)算脫顆粒比率;免疫組化法觀察藍(lán)斑組織皮膚中磷酸化MAPK(p-MAPK)陽性表達(dá)水平;Western blotting法檢測(cè)藍(lán)斑組織皮膚中MAPK-ERK1/2-JNK1/2通路蛋白表達(dá)及上游酪氨酸激酶(Lyn)、脾酪氨酸激酶(Syk)磷酸化蛋白、下游激活蛋白-1(AP-1)、炎癥通路核轉(zhuǎn)錄因子κB(NF-κB)蛋白表達(dá)。結(jié)果 與對(duì)照組相比,模型組大鼠搔抓次數(shù)增多、耳部血管通透性升高、血清IgE及炎癥介質(zhì)分泌增多、肥大細(xì)胞脫顆粒比率升高、大鼠背部皮膚水腫及炎性浸潤(rùn)等病理損傷均加重,背部藍(lán)斑組織MAPK/ERK/JNK通路活化,其下游炎癥及脫顆粒相關(guān)通路蛋白表達(dá)升高(P<0.05)。與模型組相比,染料木黃酮低、高劑量組大鼠搔抓次數(shù)減少,耳部血管通透性和肥大細(xì)胞脫顆粒比率降低,血清IgE及炎癥反應(yīng)降低,背部皮膚水腫及炎性浸潤(rùn)等病理損傷減輕,MAPK/ERK/JNK通路及其介導(dǎo)的炎癥、脫顆粒等信號(hào)途徑活化受到抑制(P<0.05),且染料木黃酮300 mg/kg組上述抑制作用更明顯(P<0.05)。茴香霉素可逆轉(zhuǎn)染料木黃酮的上述作用(P<0.05)。結(jié)論 染料木黃酮可抑制MAPK-ERK1/2-JNK1/2通路活化,阻斷肥大細(xì)胞脫顆粒,改善蕁麻疹病理癥狀。

Objective From the mitogen-activated protein kinase (MAPK)/extracellular signal-regulated kinase 1/2 (ERK1/2)/c-Jun N-terminal kinase 1/2 (JNK1/2) pathway, to explore the protective mechanism of genistein on urticaria rats. Methods SD rats were randomly divided into control group, model group, genistein low and high dose groups, MAPK activator (anisomycin) group, and genistein + anisomycin group, with 12 rats in each group. The rat model of chronic urticaria was established by serum sensitization induced by albumin. The scratching symptoms of rats were observed, ELISA method was used to detect the levels of serum immunoglobulin E antibody (IgE) and inflammatory mediators such as histamine, leukotriene, PGD2, 5-HT, etc. Evans blue staining was used to observe changes in vascular permeability. HE staining was used to observe the pathological changes of locus coeruleus skin tissue, the mast cells of the abdominal cavity was taken to calculate the degranulation ratio, immunohistochemical method was used to observe the positive expression level of phosphorylated MAPK (p-MAPK) in the skin of locus coeruleus tissue. Western Blotting method was used to detect the expression of MAPK-ERK1/2-JNK1/2 pathway protein in the skin of locus coeruleus tissue, and the expression of upstream tyrosine kinase (Lyn), spleen tyrosine kinase (Syk) phosphorylation protein, downstream activator protein-1 (AP-1) and inflammatory pathway nuclear transcription factor-κB (NF-κB) protein. Results Compared with the control group, rats in the model group had increased the number of scratches, increased ear vascular permeability, increased the secretion of serum IgE and inflammatory mediators, and mast cell degranulation rate. The pathological damage of dorsal skin edema and inflammatory infiltration was aggravated. The MAPK/ERK/JNK pathway was activated in dorsal locus coeruleus, and the protein expression of downstream inflammation and degranulation related pathway was increased (P < 0.05). Compared with model group, genistein group reduced scratching times, ear vascular permeability, and mast cell degranulation rate. And the vascular permeability and mast cell degranulation ratio were decreased, serum IgE and inflammatory response were decreased, pathological damage of back skin edema and inflammatory infiltration were alleviated, and activation of MAPK/ERK/JNK pathway and its mediated inflammation and degranulation signal pathway were inhibited (P < 0.05). The higher the dose of genistein was, the more obvious the inhibition was (P < 0.05). Anisomycin could reverse the above effects of genistein (P < 0.05). Conclusion Genistein can inhibit the activation of the MAPK-ERK1/2-JNK1/2 pathway, block the degranulation of mast cells, and improve the pathological symptoms of urticaria.

R965

河南省醫(yī)學(xué)科技攻關(guān)計(jì)劃聯(lián)合共建項(xiàng)目（LHGJ20200904）