Abstract
目的
溃疡性结肠炎(ulcerative colitis，UC)是一类以结肠黏膜及黏膜下层炎症、溃疡、糜烂为主的炎症性肠病(inflammatory bowel disease，IBD)。瞬时受体电位香草酸1(transient receptor potential vanilloid 1，TRPV1)是内脏痛及炎症性肠病的重要介质。本研究旨在探讨水溶性蜂胶(water soluble propolis，WSP)对UC结肠炎症组织的保护作用，以及TRPV1在其中的作用。
方法
将雄性SD大鼠随机分成6组(n=8)：正常对照(normal control，NC)组、UC组、低剂量蜂胶(low-WSP，L-WSP)组、中剂量蜂胶(middle-WSP，M-WSP)组、高剂量蜂胶(high-WSP，H-WSP)组和柳氮磺胺吡啶(salazosulfapyridine，SASP)组。NC组大鼠自由饮水，其余组大鼠自由饮用4%右旋糖酐硫酸钠(dextran sulfate sodium，DSS)溶液7 d后复制UC模型。在UC模型复制成功基础上，L-WSP、M-WSP、H-WSP组每天分别给予50、100、200 mg/kg的WSP灌胃处理7 d，SASP组每天给予100 mg/kg的SASP灌胃7 d。每天同一时间测量各组大鼠体重，观察其粪便性状和便血情况，行大鼠的疾病活动指数(disease activity index，DAI)评分。采用比色法检测丙二醛(malondialdehyde，MDA)的水平，ELISA法检测白细胞介素-6(interleukin-6，IL-6)、肿瘤坏死因子α(tumor necrosis factor-α，TNF-α)的变化，HE染色观察结肠病理学变化，蛋白质印迹法、免疫组织化学和免疫荧光实验观察结肠组织中TRPV1的表达情况。
结果
自由饮用DSS的各组动物出现体重下降、食欲下降、状态低迷、拖尾便血等症状，表明造模成功。与NC组相比，其余各组大鼠服用DSS后DAI评分均增加(均P<0.05)。与NC组相比，UC组大鼠血清和结肠组织中MDA、IL-6、TNF-α表达水平均升高(均P<0.01)，WSP和SASP用药后MDA、IL-6、TNF-α表达水平均降低(均P<0.01)。UC组大鼠结肠组织结构明显被破环，炎性浸润，H-WSP和SASP组结肠组织明显改善，炎性浸润缓解。与NC组相比，UC组大鼠结肠组织TRPV1的表达水平升高(均P<0.01)，WSP和SASP组结肠组织TRPV1的表达水平降低。
结论
WSP可以缓解DSS诱导的UC大鼠结肠组织的炎症状态，其机制可能与抑制炎症因子释放，下调TRPV1或TRPV1脱敏等机制有关。
Keywords: 瞬时受体电位香草酸1, 溃疡性结肠炎, 蜂胶, 炎性介质
Abstract
Objective
Ulcerative colitis (UC) is a type of inflammatory bowel disease (IBD) mainly characterized by inflammation, ulceration and erosion of colonic mucosa and submucosa. Transient receptor potential vanilloid 1 (TRPV1) is an important mediator of visceral pain and inflammatory bowel disease. This study aims to investigate the protective effect of water soluble propolis (WSP) on UC colon inflammatory tissue and the role of TRPV1.
Methods
Male SD rats were randomly divided into 6 groups (n=8): a normal control (NC) group, an ulcerative colitis model (UC) group, a low-WSP (L-WSP) group, a medium-WSP (M-WSP) group, a high-WSP (H-WSP) group, and a salazosulfapyridine (SASP) group. The rats in the NC group drank water freely, and the other groups drank 4% dextran sulfate sodium (DSS) solution freely for 7 d to replicate the ulcerative colitis model. Based on the successful replication of the UC, the L-WSP, M-WSP, and H-WSP groups were given 50, 100, and 200 mg/kg of water-soluble propolis by gavage for 7 d, and the SASP group was given 100 mg/kg of sulfasalazine by gavage for 7 d. The body weight of rats in each group was measured at the same time every day, the fecal traits and occult blood were observed to record the disease activity index (DAI). After intragastric administration, the animals were sacrificed after fasted 24 h. Serum and colonic tissue were collected, and the changes of MDA, IL-6 and TNF-α were detected. The pathological changes of colon tissues were observed by HE staining, and the expression of TRPV1 in colon tissues was observed by Western blotting, immunohistochemistry, and immunofluorescence.
Results
The animals in each group that drank DSS freely showed symptoms such as weight loss, decreased appetite, depressed state, and hematochezia, indicating that the model was successfully established. Compared with the NC group, DAI scores of other groups were increased (all P<0.05). MDA, IL-6, TNF-α in serum and colon tissues of the UC group were increased compared with the NC group (all P<0.01), and they were decreased after WSP and SASP treatment (all P<0.01). The results of showed that the colon tissue structure was obviously broken and inflammatory infiltration in the UC group, while the H-WSP group and the SASP group significantly improved the colon tissue and alleviated inflammatory infiltration. The expression of TRPV1 in colon tissues in the UC group was increased compared with the NC group (all P<0.01), and it was decreased after WSP and SASP treatment.
Conclusion
WSP can alleviate the inflammatory state of ulcerative colitis induced by DSS, which might be related to the inhibition of inflammatory factors release, and down-regulation or desensitization of TRPV1.
Keywords: transient receptor potential vanilloid 1, ulcerative colitis, propolis, inflammatory medium
溃疡性结肠炎(ulcerative colitis，UC)是一种炎症性肠病(inflammatory bowel disease，IBD)，是一类慢性胃肠道功能紊乱性疾病，病变主要累及结肠黏膜及黏膜下层，病因复杂，涉及遗传、饮食、感染、环境等多种因素，具体发病机制仍不明确[1-3]。UC的临床表现有腹痛、腹泻、血便以及体重减轻，而且此病易反复、病程长，严重影响患者的生活质量。近年来，UC的发病率呈逐年上升趋势，其治疗多采用生物制剂、抗生素、氨基水杨酸制剂、糖皮质激素等，治疗机制主要是保护肠黏膜、抗炎、清除致病源等，但疗效欠佳且不良反应多[4-5]。因此寻找安全有效的治疗UC的药物至关重要。蜂胶是蜜蜂采集植物树脂及其分泌物，混合其自身上颚腺、蜡腺的分泌物而形成的胶状物质。已有研究[6-8]表明：蜂胶具有杀菌、抗炎、镇痛、抗氧化、抗肿瘤、保护心血管系统等多种生物学功能，已被广泛应用于医药、保健品、日用护肤品等。本研究旨在探讨水溶性蜂胶(water soluble propolis，WSP)对UC的结肠组织是否具有保护作用，并探讨其保护机制是否与瞬时受体电位香草酸1(transient receptor potential vanilloid 1，TRPV1)有关。
1. 材料与方法
1.1. 材料
WSP购自广州市杰禾蜂业有限公司(20210325-B)；DSS购自Sigma公司(MP 0216011080)；SASP购自上海信谊天平药业有限公司(09210103)；白细胞介素-6(interleukin-6，IL-6)(H007-1)、肿瘤坏死因子α(tumor necrosis factor α，TNF-α)(H0052-1)、丙二醛(malondialdehyde，MDA)(a003-1)购自南京建成生物工程研究所；蛋白质印迹法、免疫组织化学(以下简称免疫组化)、免疫荧光实验一抗(anti-TRPV1，ab203103)购自英国Abcam公司；蛋白质印迹法二抗(BL001A)、免疫组化试剂盒(BL733A)购自广州硕谱生物科技有限公司；免疫荧光实验二抗(715-585-150)购自美国Jackson公司。
1.2. 实验动物分组及造模
雄性SD大鼠48只，SPF级，(200±20) g，购于杭州医学院，SCXK(浙)2019-0002，实验前自由饮食和饮水，适应性喂养1周。随后将大鼠随机分成6组(n=8)：1)正常对照(normal control，NC)组，实验过程中自由饮水，于其他组灌胃给药的相同时间点灌胃生理盐水。2)UC组，自由饮用4%右旋糖酐硫酸钠(dextran sulfate sodium，DSS)7 d复制UC模型，随后继续自由饮水喂养7 d，并在灌胃给药的相同时间点灌胃生理盐水。3)低剂量蜂胶(low-WSP，L-WSP)组，在UC模型复制成功的基础上，每天给予50 mg/kg的WSP灌胃处理7 d。4)中剂量蜂胶(middle-WSP，M-WSP)组，在UC模型复制成功的基础上，每天给予100 mg/kg的WSP灌胃处理7 d。5)高剂量蜂胶(high-WSP group，H-WSP)组，在UC模型复制成功的基础上，每天给予200 mg/kg的WSP灌胃处理7 d。6)柳氮磺胺吡啶(salazosulfapyridine，SASP)组，在UC模型复制成功的基础上，每天给予100 mg/kg的SASP灌胃处理7 d。本研究已通过皖南医学院动物伦理委员会的批准(审批号：LLSC-2021-024)。
1.3. 大鼠活动状态观察
1.3.1. 大鼠体重及大便性状观察
实验开始每天观察大鼠饮水、饮食情况，大便性状。每天同一时间点测量动物体重，将第1天体重标记为实验前起始体重。各组大鼠体重变化百分数用以下公式计算：体重变化率=[(实验后某天体重-实验前起始体重)/实验前起始体重]×100%。
1.3.2. 大鼠便血监测
使用隐血检测试剂盒检测大鼠便血情况。检测方法：取大鼠粪便，涂压于滤纸上，滴加试剂盒中A、B混合液，观察显色结果，参照表1的评分标准。
表1.
大便隐血检测判断标准
Table 1 Standard for detecting fecal occult blood
| 大便隐血 | 判断标准 |
|---|---|
| ++++ | 加入试剂后立即呈现深紫蓝色 |
| +++ | 加入试剂后10 s内产生紫蓝色 |
| ++ | 加入试剂后1 min内产生紫红色 |
| + | 加入试剂后1~2 min内产生紫红色 |
| - | 加入试剂后2 min后仍不显色 |
1.3.3. 疾病活动指数评分
从第2天开始记录体重变化、粪便性状及便血情况，根据表2的评分标准评估疾病活动指数(disease activity index，DAI)。
表2.
疾病活动指数评分标准
Table 2 Standard for scoring disease activity index
| 评分 | 体重下降率/% | 粪便性状 | 便血 |
|---|---|---|---|
| 0 | ≤1 | 正常 | - |
| 1 | 1~5 | 较软但成形 | + |
| 2 | >5~10 | 稀便 | ++ |
| 3 | >10~15 | 较重稀便，松散 | +++ |
| 4 | >15 | 水样便 | ++++ |
1.4. 标本采集
药物灌胃结束后，将大鼠禁食24 h后处死，取血清及结肠组织。结肠组织经4 ℃生理盐水清洗干净后，测量结肠长度，取一部分结肠组织置于4%多聚甲醛固定，后期用于冰冻切片，进行苏木精-伊红(hematoxylin-eosin staining，HE)染色、免疫组化和免疫荧光实验；一部分结肠组织于-80 ℃保存，用于蛋白质提取，进行炎症因子检测和蛋白质印迹法检测。
1.5. 血清及结肠组织炎症因子检测
动物处死后取血清和结肠组织，采用ELISA法检测血清和结肠组织中IL-6、TNF-α的表达水平，比色法检测血清和结肠组织中MDA的表达水平，操作按试剂盒说明书进行。
1.6. 结肠组织病理学变化观察
4%多聚甲醛固定的结肠组织，经15%和30%的蔗糖溶液各脱水1 d，用组织最佳切割温度包埋剂(optimal cutting temperature，OCT)进行包埋，经Leica冰冻切片机切成8 μm的切片，置于-20 ℃保存。切片经固定液固定45 s，水洗，苏木精染色4 min，分化，返蓝20 s，伊红染色20 s，乙醇梯度脱水，透明，封片，观察结肠组织结构变化。
1.7. 蛋白质印迹法
称取0.1 g结肠组织加1 mL裂解液，充分剪碎匀浆，静置30 min。于4 ℃，以12 000 r/min离心30 min，取上清按照4꞉1加入上样缓冲液，充分混匀后于95 ℃水浴10 min。取样5 mL经SDS-PAGE，转至PVDF膜，用脱脂牛奶封闭，TRPV1一抗孵育过夜，TBST摇洗3次后孵育二抗1 h，ECL显影液曝光拍照，Image J软件分析蛋白质条带灰度值。
1.8. 免疫组化实验
取-20 ℃保存的切片室温晾干，于37 ℃烘箱烤片2 h，用3% H2O2室温孵育30 min，5% BSA封闭20 min，一抗孵育过夜，生物素孵育2 h，SABC复合物孵育 30 min，DAB显色，HE染色10 s，盐酸乙醇分色，乙醇梯度脱水，封片，镜下观察，Image pro plus软件分析TRPV1在结肠组织的相对表达。
1.9. 免疫荧光实验
取-20 ℃保存的切片在室温下晾干，于37 ℃烘箱中烤片2 h，用马血清于暗盒中封闭30 min，一抗孵育过夜，恢复室温37 ℃烤片30 min，PBS摇洗，二抗暗室孵育2 h，最后30 min加入DAPI，在激光共聚焦显微镜下观察，Image pro plus软件分析TRPV1在结肠组织表达的荧光强度。
1.10. 统计学处理
采用SPSS 18.0统计软件分析数据。计量资料以均数±标准差( ±s)表示，多组间比较采用单因素方差分析和重复测量方差分析，多组间两两比较采用LSD-t检验，P<0.05为差异有统计学意义。
2. 结 果
2.1. WSP对UC大鼠体重的影响
NC组大鼠体重呈缓慢增长趋势，其他组大鼠在服用DSS后体重呈逐渐下降趋势，从第6天开始与NC组的差异有统计学意义(P<0.05)。与UC组相比，M-WSP(P<0.05)、H-WSP(P<0.01)和SASP组(P<0.01)用药5 d后，大鼠体重出现增长趋势(表3)。
表3.
实验过程中大鼠体重的变化(n=8)
Table 3 Changes in body weight of rats during the experiment (n=8)
| Group | Weight/g | ||||||
|---|---|---|---|---|---|---|---|
| Day 2 | Day 4 | Day 6 | Day 8 | Day 10 | Day 12 | Day 14 | |
| NC | 242.27±17.62 | 253.47±19.43 | 267.72±16.25 | 278.39±19.22 | 288.12±21.30 | 295.58±18.56 | 305.85±17.41 |
| UC | 240.06±14.32 | 242.22±17.55 | 238.01±13.17* | 235.05±15.16** | 226.41±14.84** | 220.23±13.37** | 207.31±10.19** |
| L-WSP | 236.43±6.91 | 240.45±9.20 | 240.65±16.76* | 244.30±18.00** | 238.52±14.41** | 246.03±15.23** | 245.98±18.61** |
| M-WSP | 246.67±8.92 | 253.00±6.92 | 246.00±6.35* | 244.20± 4.41** | 252.04±6.29** | 255.07±7.37**† | 257.16±8.42**†† |
| H-WSP | 242.34±14.57 | 250.62±11.04 | 254.00±2.84* | 248.04± 6.28** | 256.96±11.21** | 259.86±16.94**†† | 267.41±21.35**†† |
| SASP | 244.51±6.95 | 248.05±5.76 | 252.35±6.65* | 255.66±6.12** | 259.33±6.50** | 266.83±4.53**†† | 275.51±5.39**†† |
**P<0.01 vs the NC group; †P<0.05, ††P<0.01 vs the UC group. NC: Normal control; UC: Ulcerative colitis; WSP: Water soluble propolis; L-WSP: Low-WSP; M-WSP: Middle-WSP; H-WSP: High-WSP; SASP: Salazosulfapyridine.
2.2. WSP对UC大鼠结肠长度的影响
与NC组相比，UC组大鼠结肠明显变短(P<0.01)；与UC组相比，WSP组和SASP组的结肠长度均增加(均P<0.01，图1)。
图1.
实验结束后大鼠结肠的长度(n=8)
Figure 1 Colon length after the experiment (n=8)
*P<0.05, **P<0.01 vs the NC group; †P<0.05, ††P<0.01 vs the UC group. NC: Normal control; UC: Ulcerative colitis; WSP: Water soluble propolis; L-WSP: Low-WSP; M-WSP: Middle-WSP; H-WSP: High-WSP; SASP: Salazosulfapyridine.
2.3. WSP对UC大鼠DAI评分的影响
与NC组相比，其他各组大鼠DAI评分均有升高(第2天P<0.05，第6天起P<0.01)。与UC组相比，H-WSP和SASP组大鼠在第10天(给药后第3天)DAI评分明显降低(P<0.05)；至第14天(给药后第7天)，M-WSP、H-WSP和SASP组大鼠DAI评分均显著降低 (均P<0.01，图2)。
图2.
实验过程中大鼠DAI评分的变化(n=8)
Figure 2 Changes in DAI scores of rats during the experiment (n=8)
*P<0.05, **P<0.01 vs the NC group; †P<0.05, ††P<0.01 vs the UC group. NC: Normal control; UC: Ulcerative colitis; WSP: Water soluble propolis; L-WSP: Low-WSP; M-WSP: Middle-WSP; H-WSP: High-WSP; SASP: Salazosulfapyridine.
2.4. 结肠组织炎症因子水平变化
与NC组相比，UC组大鼠结肠组织和血清中IL-6、TNF-α、MDA水平均显著升高(均P<0.01)。与UC组相比，M-WSP、H-WSP和SASP组灌胃给药7 d后，大鼠结肠组织和血清中IL-6、TNF-α、MDA水平均明显降低(均P<0.01)；L-WSP组血清中IL-6、TNF-α水平均降低(均P<0.05)，L-WSP组结肠组织中TNF-α、MDA水平均显著降低(均P<0.01，图3)。
图3.
大鼠血清和结肠组织炎症因子变化(n=8)
Figure 3 Changes of inflammatory factors in serum and colonic tissue (n=8)
*P<0.05, **P<0.01 vs the NC group; †P<0.05, ††P<0.01 vs the UC group. NC: Normal control; UC: Ulcerative colitis; WSP: Water soluble propolis; L-WSP: Low-WSP; M-WSP: Middle-WSP; H-WSP: High-WSP; SASP: Salazosulfapyridine.
2.5. 结肠组织HE染色结果
HE染色结果显示：与NC组大鼠结肠组织结构相比，UC组大鼠结肠黏膜损伤严重，有明显溃疡和炎症，上皮细胞大面积脱落，隐窝出现不同程度的损伤。经WSP和SASP灌胃给药后，结肠组织有不同程度的修复，炎性浸润逐渐消失，上皮细胞和隐窝损伤逐渐修复(图4)。
图4.
结肠组织HE染色结果
Figure 4 HE staining of colonic tissue in the groups
A: Glands are aligned without inflammatory infiltration. B: Glands are partially absent, severely damaged, and have severe inflammatory infiltration. C: Glands are partially injured, scattered ulcers are obvious, and some inflammatory infiltrates are observed. D: Glands are a small amount of inflammatory infiltration with a small number of scattered ulcers. E: Structure of the glands is basically restored and aligned. F: Structure of the glands is basically restored and aligned. NC: Normal control; UC: Ulcerative colitis; WSP: Water soluble propolis; L-WSP: Low-WSP; M-WSP: Middle-WSP; H-WSP: High-WSP; SASP: Salazosulfapyridine.
2.6. 蛋白质印迹法检测结肠组织中TRPV1的表达
蛋白质印迹法结果显示：与NC组相比，UC组大鼠结肠组织TRPV1表达水平明显升高(P<0.01)；与UC组相比，L-WSP组(P<0.05)、M-WSP组(P<0.01)、H-WSP组(P<0.01)和SASP组(P<0.01)大鼠结肠组织的TRPV1表达水平均降低(图5)。
图5.
大鼠结肠组织TRPV1表达情况
Figure 5 TRPV1 expression in colon tissue of rats
**P<0.01 vs the NC group; †P<0.05, ††P<0.01 vs the UC group. NC: Normal control; UC: Ulcerative colitis; WSP: Water soluble propolis; L-WSP: Low-WSP; M-WSP: Middle-WSP; H-WSP: High-WSP; SASP: Salazosulfapyridine.
2.7. 免疫组化检测结肠组织中TRPV1的表达
免疫组化结果显示：与NC组相比，UC组大鼠结肠组织TRPV1的表达水平明显升高(P<0.01)；与UC组相比，WSP和SASP用药组大鼠结肠组织的TRPV1的表达水平均显著降低(均P<0.01，图6)。
图6.
结肠组织TRPV1免疫组化染色结果
Figure 6 TRPV1 immunohistochemical staining of colon tissue
**P<0.01 vs the NC group; ††P<0.01 vs the UC group. NC: Normal control; UC: Ulcerative colitis; WSP: Water soluble propolis; L-WSP: Low-WSP; M-WSP: Middle-WSP; H-WSP: High-WSP; SASP: Salazosulfapyridine.
2.8. 免疫荧光检测结肠组织TRPV1的表达
免疫荧光结果显示：与NC组相比，UC组大鼠结肠组织TRPV1荧光染色强度明显增加(P<0.01)；与UC组相比，WSP和SASP组大鼠结肠组织的TRPV1荧光染色强度均显著降低(均P<0.01)；其中H-WSP和SASP组TRPV1荧光染色强度与NC组差异无统计学意义(均P>0.05，图7、8)。
图7.
结肠组织TRPV1免疫荧光染色图
Figure 7 TRPV1 immunofluorescence staining of colon tissue
NC: Normal control; UC: Ulcerative colitis; WSP: Water soluble propolis; L-WSP: Low-WSP; M-WSP: Middle-WSP; H-WSP: High-WSP; SASP: Salazosulfapyridine; DAPI: 4', 6-diamidino-2-phenylindole; TRPV1: Transient receptor potential vanilloid 1.
图8.
结肠组织TRPV1免疫荧光染色结果(n=3)
Figure 8 Results of TRPV1 immunofluorescence staining of colon tissue (n=3)
*P<0.05, **P<0.01 vs the NC group; ††P<0.01 vs the UC group. TRPV1: Transient receptor potential vanilloid 1; NC: Normal control; UC: Ulcerative colitis; WSP: Water soluble propolis; L-WSP: Low-WSP; M-WSP: Middle-WSP; H-WSP: High-WSP; SASP: Salazosulfapyridine.
3. 讨 论
瞬时受体电位(transient receptor potential，TRP)家族是一类位于细胞膜和胞内细胞器膜上的非电压依赖性阳离子通道，广泛分布于中枢和外周神经系统，是躯体和内脏伤害性信号的感受者和传导者[5]。TRP通道通过调节炎症因子、趋化因子和免疫细胞等参与IBD的发展，TRP通道的敏化可以降低刺激的阈值，而TRP通道脱敏可以阻止伤害性信号的转入，在炎症反应期间，TRP通道对刺激更加敏感，所以TRP通道被看作是治疗炎性疾病的新靶点[9-10]。TRPV1是最早发现的TRP家族的亚型之一，同样广泛分布于中枢和外周神经系统，心血管系统，消化系统、呼吸系统等[11]，TRPV1可以调控多种组织和器官的功能，如参与脂类代谢，具有减肥的功效[12]；参与肝脏代谢，防止肝脏脂肪变性[13]；减少动脉粥样斑块形成[14]；改善线粒体功能，增强心肌功能[15]；还参与呼吸、消化、泌尿、生殖和皮肤等系统疾病的发生[16-17]；甚至与某些肿瘤的发病相关[18]。近期有研究[19]表明：多食辣能降低血压，改善血脂，减少心血管疾病的发生。
TRPV1可以被辣椒素、炎症介质、高温(>43 ℃)等有害刺激激活，引起Na+、Ca2+、Mg2+等阳离子跨膜移动，产生动作电位，继而产生痛觉。TRPV1参与IBD免疫炎症反应，促进T细胞介导的结肠炎肠道炎症反应，当TRPV1被抑制后，T细胞介导的结肠炎症状减轻。研究[20]发现TRPV1可以通过调节结肠中树突状细胞，提高促炎因子表达，增强Th17免疫反应，来增加DSS诱导的UC小鼠的易感性。TRPV1是内脏痛觉和炎症发生的关键介质，本研究发现WSP对DSS诱导的UC结肠组织具有很好的保护作用，同时降低了结肠组织和外周血中炎症因子水平。UC组大鼠结肠组织TRPV1高表达，使用WSP和SASP后，UC结肠组织损伤得到有效缓解，同时结肠组织TRPV1表达降低。由此推测，WSP对UC结肠组织的保护作用与TRPV1有关。蛋白质印迹法、免疫组化实验、免疫荧光实验均证实蜂胶对UC炎症组织的改善作用与TRPV1有关。炎症因子可以通过激活G蛋白偶联受体致敏TRPV1，从而产生痛觉过敏，同时TRPV1的激活促进炎症因子的释放，它们互相促进放大痛觉感受[20]，这与本研究结果一致，在UC发生过程中，炎症因子和TRPV1有相互促进效应，致使结肠组织发生溃疡及痛觉反应。使用WSP和SASP后，炎症因子和TRPV1表达均出现下降趋势，表明在UC发生和修复过程中，炎症因子和TRPV1都起到重要作用。
本研究明确了WSP降低结肠组织炎症因子释放以及TRPV1的表达，并具有一定的浓度依赖性，但尚未阐明WSP与TRPV1表达降低的具体分子机制，未来我们将进一步探索WSP与TRPV1在防治UC中的相互关系及其分子机制。
基金资助
安徽省高校自然科学研究项目(2022AH051243)；皖南医学院中青年重点科研项目(WK2022Z03)；国家级大学生创新创业训练计划项目(202110368034)。
This work was supported by the Natural Science Research Project of Anhui Province (2022AH051243), the Key Fund for Young People of Wannan Medical College (WK2022Z03), and the College Students Innovation and Entrepreneurship Program (202110368034), China.
利益冲突声明
作者声称无任何利益冲突。
作者贡献
王静 实验设计与操作，论文撰写与修改；钱臻、卢泰愚、李瑞瑞 实验操作，数据统计分析；李慧、张浩、孙丽 实验数据采集；王海华 实验设计与指导，论文修改。所有作者阅读并同意最终文本。
原文网址
http://xbyxb.csu.edu.cn/xbwk/fileup/PDF/202302182.pdf
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