红景天对大鼠重症急性胰腺炎的治疗作用及机制研究

An investigation on mechanisms and therapeutic effects of rhodiola on severe acute pancreatitis in rats

目的探讨红景天治疗重症急性胰腺炎（SAP）大鼠的作用及机制。方法将72只健康SD大鼠按随机数字表法分为对照组、SAP模型组、红景天干预组，每组24只。采用胰头夹闭法复制SAP模型；对照组开腹仅翻动胰腺3次然后关腹。对照组和SAP模型组给予10mL／kg0．9％生理盐水（NS）腹腔注射，红景天干预组腹腔注射10mL／kg的红景天注射液。于制模后12、24、36h随机取8只大鼠检测各组血淀粉酶、脂肪酶水平；用酶联免疫吸附试验（ELISA）检测血清白细胞介素（IL-1β、IL-6和IL-10）含量，再取胰腺组织行病理组织学观察，用间羟胺法检测大鼠胰腺组织超氧化物歧化酶（SOD）含量，用反转录一聚合酶链反应（RT—PCR）检测大鼠胰腺组织诱导型一氧化氮合酶（iNOS）mRNA表达水平。结果SAP模型组血淀粉酶、脂肪酶、IL-1β、IL-6、IL-10水平及胰腺组织iNOSmRNA表达水平均显著高于对照组，而SOD水平较对照组明显降低，以制模型后36h变化更显著[血淀粉酶（U／L）：4155．0±240．1比917．4±44，0，脂肪酶（U／L）：401．0±20．4比66．7±7．2，SOD（U／mg）：37．0±5．6比79．7±6．7，IL-1B（ng／L）：469．4±27．5比51．0±6．0，IL-6（ng／L）：467．4±28．2比58．0±6．0，IL-10（ng／L）：242．6±18．9比81．0±6．0，iNOS mRNA（×10^2）：88．5±11．4比0]；红景天干预组血淀粉酶、脂肪酶和IL-18、IL-6、iNOS mRNA水平较SAP模型组显著降低，而IL-10与SOD较SAP模型组明显升高，以制模型后制模后36h变化更显著，红景天干预组血淀粉酶（U／L）为3656．8±162．4，血脂肪酶（U／L）为360．8±16．9，SOD（U／mg）为46．8±5．8，IL-1β（ng／L）为357．6±24．1，IL-6（ng／L）为356．9±23．5，IL-10（ng／L）为372．6±21．4，iNOS mRNA（×10^2）为61．2±9．8，红景天干预组与模型组比较差异均有统计学意义（均P〈0．05）。对照组各时间点胰腺组织无异常；SAP模型组可见胰腺组织轻度肿胀，胰腺血管扩张；红景天干预组较SAP模型组胰腺损伤减轻。光镜下可见对照组胰腺组织结构无异常，SAP模型组胰腺间质水肿和大量炎性细胞浸润，胰腺泡细胞呈空泡样变和局灶性坏死，胰周脂肪组织坏死，部分腺泡细胞溶解，只剩下残留解体细胞。而红景天干预组见胰腺仍充血肿胀，但间质中炎性细胞明显减少，仅有点状出血坏死。结论红景天对SAP大鼠有较好的治疗作用，主要与抑制大鼠胰腺组织促炎细胞因子IL-1B、IL-6水平，促进抗炎性因子IL-10表达，阻止抗氧化酶SOD的下降，下调iNOS的mRNA表达，减少氧自由基的生成及一氧化氮（NO）对胰腺细胞的损害和提高胰腺的耐缺氧能力有关。

Objective To explore ihe therapeutic effects of rhodiola on severe acute pancreatitis （SAP） in rats and its mechanisms. Methods A total of 72 healthy Sprague-Dawley （SD） rats were divided into a control group, SAP model group, and a rhodiola-treated group （RTO group） by random number table, 24 rats in each group. The SAP model was replicated by the method of pancreatic head clamping. The pancreas was flipped only 3 times and then the abdomen was closed in the control group. The rats in control and SAP model groups were peritoneally injected with 10 mL/kg 0.9% normal saline after modeling in the latter group, while the rats in the RTO group were peritoneally injected with 10 mL/kg rhodiola injection. Eight rats were randomly selected from each group at 12, 24, and 36 hours after modeling to detect levels of serum amylase and lipase; serum levels of intedeukin （IL-1 β, IL-6 and IL-10） were detected by enzyme-linked immunosorbent assay （ELISA）. Pathological changes of the pancreas were observed under light microscope, the superoxide dismutase （SOD） content of pancreas was detected by xanthine oxidase method. The expression level of inducible nitric oxide synthase （iNOS） mRNA in the rat pancreatic tissue was detected by reverse transcription- polymerase chain reaction （RT-PCR）. Results Compared with the control group, the serum levels of amylase, lipase, IL-1 β, IL-6, IL-10, and the iNOS mRNA expression in pancreatic tissue were significantly higher in the SAP model group （P 〈 0.05）, the SOD level was obviously decreased in the SAP model group compared with that in control group, and the degree of change at 36 hours after modeling was more significant [the serum amylase （U/L）： 4 155.0 ± 240.1 vs. 917.4 ± 44.0, the lipase （U/L）： 401.0 ± 20.4 vs. 66.7 ± 7.2, the SOD （U/mg）： 37.0 ± 5.6 vs. 79.7 ± 6.7, the IL-1 ± （ng/L）：469.4 ± 27.5 vs. 51.0 ± 6.0, the IL-6 （ng/L）： 467.4 ±28.2 vs. 58.0 ± 6.0, the IL-10 （ng/L）： 242.6 ± 18.9 vs. 81.0 ± 6.0, the iNOS mRNA （× 10^2）： 88.5 ± 11.4 vs. 0]. Compared with the SAP model group, the levels of amylase, lipase, IL-1β, IL-6, and iNOS mRNA were significantly lower, but SOD and IL-10 levels were significantly higher in the RTO group, and the degrees of change at 36 hours after modeling were more significant [the serum amylase （U/L） was 3 656.8 ± 162.4, the lipase （U/L） was 360.8 ± 16.9, the SOD （U/mg） was 46.8 ± 5.8, the IL-1 β（ng/L） was 357.6 ± 24.1, the IL-6 （ng/L） was 356.9 ± 23.5, IL-10 （ng/L） was 372.6 ± 21.4, iNOS mRNA （× 10^2） was 61.2 ±9.8, all P 〈 0.05]. At each time point, the pancreatic tissues were not of any abnormal changes in the control group; in the SAP model group, the mild swelling of pancreatic tissue and slight blood vessel dilatation could be seen. The morphological damage of pancreas in the RTO group was milder than that in the SAP model group. Under light microscope, there were no abnormal changes in pancreatic tissue in the control group, while in the SAP model group, the pancreatic pathologic changes included interstitial edema with a large amount of inflammatory cell infiltration, acinar cells representing vacuole-like changes, focal necrosis, fat necrosis at the periphery of pancreas, some of the alveolar cells being dissolved, leaving only the remaining disintegrating cells. In the RTO group, the pancreas was still hyperemie and swelling, but interstitial inflammatory cells were significantly less than those in the SAP model group, only could petechial hemorrhage and spotty necrosis be seen. Conclusions Rhodiola has relatively good therapeutic effect on SAP in rats, which might be related mainly to its actions of inhibiting the levels of IL-1 β, IL-6 to promote inflammation, stimulating the expression of anti-inflammatory factor IL-10, preventing the decrease of anti-oxidation enzyme SOD, down-regulating iNOS mRNA expression, reducing the generation of oxygen free radicals and NO damage to pancreatic cells, and improving the pancreas capability of hypoxia tolerance.