目的 探討黃芩苷調控?；撬嵘险{基因1（taurine up-regulated gene 1，TUG1）/多嘧啶束結合蛋白1（polypyrimidine tract binding protein 1，PTBP1）/核苷酸結合寡聚化結構域樣受體蛋白3（nucleotide-binding oligomerization domain-like receptor protein 3，NLRP3）分子網絡抑制巨噬細胞焦亡治療潰瘍性結腸炎（ulcerative colitis，UC）的作用機制。方法 利用葡聚糖硫酸鈉（dextran sulfate sodium salt，DSS）誘導構建UC小鼠模型，將小鼠隨機分為對照組、模型組、美沙拉嗪（600 mg/kg）組和黃芩苷低、中、高劑量（25、50、100 mg/kg）組，連續(xù)ig給藥處理7 d，觀察小鼠日常活動變化，蘇木素-伊紅（hematoxylin eosin，HE）染色和透射電鏡觀察結腸組織的結構變化，生化檢測血清中髓過氧化物酶（myeloperoxidase，MPO）活性。通過脂多糖（lipopolysaccharide，LPS）＋三磷酸腺苷（adenosine triphosphate，ATP）誘導THP-1細胞分化構建UC體外模型，將其隨機分為對照組、模型組、美沙拉嗪（100μmol/L）組、黃芩苷不同劑量組。酶聯(lián)免疫吸附測定（enzyme linked immunosorbent assay，ELISA）檢測血清和細胞中白細胞介素-1β（interleukin-1β，IL-1β）、IL-18表達；流式檢測結腸組織和細胞中半胱氨酸天冬氨酸蛋白酶-1（cystein-asparate protease-1，Caspase-1）表達；Western blotting檢測結腸組織和細胞中PTBP1、NLRP3、凋亡相關顆粒樣蛋白（apoptosis-associated speck-like protein containing a CARD，ASC）、Caspase-1、GSDMD蛋白C端片段（gasdermin D-C，GSDMD-C）、GSDMD-N蛋白表達；逆轉錄實時定量聚合酶鏈式反應（reverse transcription quantitative polymerase chain reaction，RT-qPCR）檢測TUGI、PTBP1、NLRP3表達。RNA pull-down和RNA結合蛋白免疫沉淀（RNA immunoprecipitation，RIP）驗證TUG1與PTBP1的相互作用；挽救實驗進一步驗證TUG1-PTBP1在UC中調控巨噬細胞焦亡的作用。結果 體內外研究表明，與模型組比較，黃芩苷能夠顯著降低UC小鼠的疾病活動指數(shù)（disease activity index，DAI）評分（P＜0.001），抑制結腸縮短，減輕結腸病理損傷，降低IL-1β、IL-18、MPO、Caspase-1表達（P＜0.01、0.001），降低結腸組織和細胞中焦亡相關指標的表達（P＜0.05、0.01、0.001），其中以高劑量黃芩苷效果最為明顯。此外，黃芩苷通過降低TUG1的表達，影響PTBP1與TUG1的結合，進而抑制NLRP3炎癥體的活化，從而抑制巨噬細胞焦亡。結論 黃芩苷能夠有效緩解UC，可能與調控TUG1/PTBP1/NLRP3分子網絡抑制巨噬細胞焦亡有關。

Objective To explore the mechanism of action of baicalin in regulating the taurine up-regulated gene 1 (TUG1)/ polypyrimidine tract binding protein 1 (PTBP1)/nucleotide-binding oligomerization domain-like receptor protein 3 (NLRP3) molecular network to inhibit macrophage pyroptosis for the treatment of ulcerative colitis (UC).Methods UC mouse model was constructed using dextran sulfate sodium salt (DSS) induction, and the mice were randomly divided into control group, model group, mesalazine (600 mg/kg) group, and baicalin low, medium, and high dosage (25, 50, and 100 mg/kg) groups, and treated with baicalin administered by consecutive gavage for 7 d, and the changes in the daily activities of mice were observed, and the structural changes in colonic tissues were observed by hematoxylin eosin (HE) staining and transmission electron microscopy, and biochemical detection was performed on the activity of myeloperoxidase (MPO) in serum. An in vitro model of UC was constructed by lipopolysaccharide (LPS) + adenosine triphosphate (ATP)-induced THP-1 cell differentiation, and the mice were randomly divided into control, model, mesalazine (100 μmol/L), and baicalin intervention groups with different doses.The expression of interleukin-1β (IL-1β) and IL-18 in serum and cells was detected by enzyme-linked immunosorbent assay (ELISA), the expression of cystein-asparate protease-1 (Caspase-1) in colon tissues and cells was detected by flow cytometry; the expression of PTBP1, NLRP3, apoptosis-associated speck-like protein containing a CARD (ASC), Caspase-1, gasdermin D-C (GSDMD-C), GSDMD-N protein in colon tissues and cells was detected byWestern blotting; reverse transcription quantitative polymerase chain reaction (RT-qPCR) was used to detect TUGI, PTBP1, NLRP3 expression. RNA pull-down and RNA immunoprecipitation (RIP) were used to verify the interaction between TUG1 and PTBP1; rescue experiments were used to further validate the effect of TUG1-PTBP1 in UC to regulate macrophage pyroptosis. Results In vitro and in vivo studies showed that baicalin significantly reduced disease activity index (DAI) (P < 0.001), inhibited colonic shortening, attenuated colonic pathological injury, decreased the expression of IL-1β, IL-18, MPO and Caspase-1 (P < 0.01, 0.001), and decreased the expression of pyroptosis-related indexes in colonic tissues and cells in UC mice compared with the model group (P < 0.05, 0.01, 0.001), and the effect of baicalin was most obvious at high doses. In addition, baicalin inhibited macrophage pyroptosis by decreasing the expression of TUG1 and affecting the binding of PTBP1 to TUG1, which in turn inhibited the activation of NLRP3 inflammasome. Conclusion Baicalin can effectively alleviate UC, which may be related to the inhibition of macrophage pyroptosis by regulating the TUG1/PTBP1/NLRP3 molecular network.

R285.5

2022年度湖南省自然科學基金青年基金項目（2022JJ40325）;湖南省第一批中醫(yī)藥學科帶頭人（神農學者）（2100601）;中醫(yī)藥人才培養(yǎng)重點學科（中醫(yī)肛腸病學）（2023-01-16-006-011）