Low-molecular-weight dextran for optical coherence tomography may not be protective against kidney injury in patients with renal insufficiency

BACKGROUND Low-molecular-weight dextran(LMWD)is considered a safe alternative to contrast media for blood displacement during optical coherence tomography(OCT)imaging.AIM To investigate whether the use of LMWD for OCT is protective against kidney injury in patients with advanced renal insufficiency.METHODS In this retrospective cohort study,we identified 421 patients with advanced renal insufficiency(estimated glomerular filtration rate<45 mL/min/1.73 m2)who underwent coronary angiography or percutaneous coronary intervention;79 patients who used additional LMWD for OCT imaging(LMWD group)and 342 patients who used contrast medium exclusively(control group).We evaluated the differences between these two groups and performed a propensity score-matched subgroup comparison.RESULTS The median total volume of contrast medium was 133.0 mL in the control group vs 140.0 mL in the LMWD group.Although baseline renal function was not statistically different between these two groups,the LMWD group demonstrated a strong trend toward the progression of renal insufficiency as indicated by the greater change in serum creatinine level during the 1-year follow-up compared with the control group.Patients in the LMWD group experienced worsening renal function more frequently than patients in the control group.Propensity score matching adjusted for total contrast media volume consistently indicated a trend toward worsening renal function in the LMWD group at the 1-year follow-up.Delta serum creatinine at 1-year follow-up was significantly greater in the LMWD group than that in the control group[0.06(-0.06,0.29)vs-0.04(-0.23,0.08)mg/dL,P=0.001],despite using similar contrast volume.CONCLUSION OCT using LMWD may not be protective against worsening renal function in patients with advanced renal insufficiency.

Low-molecular-weight heparin and preeclampsia—does the sword cut both ways?Three case reports and review of literature

BACKGROUND Low-molecular-weight heparins(LMWH)are the most commonly used anticoagulants during pregnancy.It is considered to be the drug of choice due to its safety in not crossing placenta.Considering the beneficial effect in the improvement of microcirculation,prophylactic application of LMWH in patients with preeclampsia became a trend.However,the bleeding risk related with LMWH in preeclampsia patients has seldomly been evaluated.This current study aimed to identify the potential risks regarding LMWH application in patients with preeclampsia.CASE SUMMARY Herein we present a case series of three pregnant women diagnosed with preeclampsia on LMWH therapy during pregnancy.All the cases experienced catastrophic hemorrhagic events.After reviewing the twenty-one meta-analyses,the bleeding risk related with LMWH seems ignorable.Only one study analyzed the bleeding risk of LMWH and found a significantly higher risk of developing PPH in women receiving LMWH.Other studies reported minor bleeding risks,none of these were serious enough to stop LMWH treatment.Possibilities of bleeding either from uterus or from intrabdominal organs in preeclampsia patients on LMWH therapy should not be ignored.Intensive management of blood pressure even after delivery and homeostasis suture in surgery are crucial.CONCLUSION Consideration should be given to the balance between benefits and risks of LMWH in patients with preeclampsia.

Differences in the effects and action modes of gut commensals against dextran sulfate sodium-induced intestinal inflammation

Inflammatory bowel disease(IBD)is a complex relapsing inflammatory disease in the gut and is driven by complicated host-gut microbiome interactions.Gut commensals have shown different functions in IBD prevention and treatment.To gain a mechanistic understanding of how different commensals affect intestinal inflammation,we compared the protective effects of 6 probiotics(belonging to the genera Akkermansia,Bifidobacterium,Clostridium,and Enterococcus)on dextran sulfate sodium(DSS)-induced colitis in mice with or without gut microbiota.Anti-inflammatory properties(ratio of interleukin(IL)-10 and IL-12)of these strains were also evaluated in an in vitro mesenteric lymph nodes(MLN)co-culture system.Results showed that 4 probiotics(belonging to the species Bifidobacterium breve,Bifidobacterium bifidum,and Enterococcus faecalis)can alleviate colitis in normal mice.The probiotic strains differed in regulating the intestinal microbiota,cytokines(IL-10,IL-1βand interferon(IFN)-γ),and tight junction function(Zonulin-1 and Occludin).By constrast,Akkermansia muciniphila AH39 and Clostridium butyricum FHuNHHMY49T1 were not protective.Interestingly,B.breve JSNJJNM2 with high anti-inflammatory potential in the MLN model could relieve colitis symptoms in antibiotic cocktail(Abx)-treated mice.Meanwhile,E.faecalis FJSWX25M1induced low levels of cytokines in vitro and showed no beneficial effects.Therefore,we provided insight into the clinical application of probiotics in IBD treatment.

Low-molecular-weight fucoidan inhibits the proliferation of melanoma via Bcl-2 phosphorylation and PTEN/AKT pathway

Fucoidan,a sulfate polysaccharide obtained from brown seaweed,has various bioactive properties,including anti-inflammatory,anti-cancer,anti-viral,anti-oxidant,anti-coagulant,anti-thrombotic,anti-angiogenic,and anti-Helicobacter pylori properties.However,the effects of low-molecular-weight fucoidan(LMW-F)on melanoma cell lines and three dimensional(3D)cell culture models are not well understood.This study aimed to investigate the effects of LMW-F on A375 human melanoma cells and cryopreserved biospecimens derived from patients with advanced melanoma.Ultrasonic wave was used to fragment fucoidan derived from Fucus vesiculosus into smaller LMW-F.MTT and live/dead assays showed that LMW-F inhibited cell proliferation in both A375 cells and patientderived melanoma explants in a 3D-printed collagen scaffold.The PTEN/AKT pathway was found to be involved in the anti-melanoma effects of fucoidan.Western blot analysis revealed that LMW-F reduced the phosphorylation of Bcl-2 at Thr 56,which was associated with the prevention of anti-apoptotic activity of cancer cells.Our findings suggested that LMW-F could enhance anti-melanoma chemotherapy and improve the outcomes of patients with melanoma resistance.

Alkaline sphingomyelinase deficiency impairs intestinal mucosal barrier integrity and reduces antioxidant capacity in dextran sulfate sodium-induced colitis

BACKGROUND Ulcerative colitis is a chronic inflammatory disease of the colon with an unknown etiology.Alkaline sphingomyelinase(alk-SMase)is specifically expressed by intestinal epithelial cells,and has been reported to play an anti-inflammatory role.However,the underlying mechanism is still unclear.AIM To explore the mechanism of alk-SMase anti-inflammatory effects on intestinal barrier function and oxidative stress in dextran sulfate sodium(DSS)-induced colitis.METHODS Mice were administered 3%DSS drinking water,and disease activity index was determined to evaluate the status of colitis.Intestinal permeability was evaluated by gavage administration of fluorescein isothiocyanate dextran,and bacterial translocation was evaluated by measuring serum lipopolysaccharide.Intestinal epithelial cell ultrastructure was observed by electron microscopy.Western blotting and quantitative real-time reverse transcription-polymerase chain reaction were used to detect the expression of intestinal barrier proteins and mRNA,respectively.Serum oxidant and antioxidant marker levels were analyzed using commercial kits to assess oxidative stress levels.RESULTS Compared to wild-type(WT)mice,inflammation and intestinal permeability in alk-SMase knockout(KO)mice were more severe beginning 4 d after DSS induction.The mRNA and protein levels of intestinal barrier proteins,including zonula occludens-1,occludin,claudin-3,claudin-5,claudin-8,mucin 2,and secretory immunoglobulin A,were significantly reduced on 4 d after DSS treatment.Ultrastructural observations revealed progressive damage to the tight junctions of intestinal epithelial cells.Furthermore,by day 4,mitochondria appeared swollen and degenerated.Additionally,compared to WT mice,serum malondialdehyde levels in KO mice were higher,and the antioxidant capacity was significantly lower.The expression of the transcription factor nuclear factor erythroid 2-related factor 2(Nrf2)in the colonic mucosal tissue of KO mice was significantly decreased after DSS treatment.mRNA levels of Nrf2-regulated downstream antioxidant enzymes were also decreased.Finally,colitis in KO mice could be effectively relieved by the injection of tertiary butylhydroquinone,which is an Nrf2 activator.CONCLUSION Alk-SMase regulates the stability of the intestinal mucosal barrier and enhances antioxidant activity through the Nrf2 signaling pathway.

Dextran微球末梢性肝动脉栓塞治疗肝癌的实验研究及临床初步应用

采用Dextran微球G—50,φ50～150μ作实验性肝肾动脉栓塞及临床肝动脉栓塞治疗肝癌,并以1×1×1mm明胶海绵颗粒作近侧性肝动脉栓塞作为对照。研究结果表明:Dextran微球能产生更为均一、更为末梢的微动脉栓塞。动物实验及临床应用均表明,它能栓塞到直径约100μ的微动脉水平。实验动物肝动脉栓塞后8周,微球仍不为组织所吸收;人体肝动脉栓塞后16周微球依然存在。能有效地减少或阻止肝肿瘤患者肝动脉栓塞后肝内、外侧支循环的建立,栓塞对癌瘤主灶及子灶均有显著作用。因此,Dextran微球是一很有希望的长效栓塞剂。

Effect of Berberine Chloride on Experimental Murine Colitis Induced by Dextran Sulfate Sodium

Aim To investigate the effect in berberine chloride （BER） on experimental ulcerative colitis in mice. Methods BALB/C mice in 6 groups were allowed to drink either 4% dextran sulfate sodium （DSS） solution or distilled water freely with different doses of BER （15 mg·kg^-1, 45 mg·kg^-1, 150 mg·kg^-1） or sallcylazosulfapyridine （SASP, 520 mg·kg^-1）, and solvent （0. 2 mL/10 mg Wt） once a day for 7 d, respectively. The symptom of ulcerative colitis was evaluated by disease activity index （DAI）. Myeloperoxidase （MPO） and superoxide dismutase （SOD） activities and malondialdehyde （MDA） content were determined by HE staining and immunohistochemistry of expressions of NF-κB p65 and intercellular adhesion molecule 1 （ ICAM-1 ） proteins to observe the damage to colon tissues and possible mechanisms. Results DAI, MPO activity, MDA content and expressions of ICAM-1 and NF-κB p65 were markedly increased, while SOD activity decreased in DSS-treated mice. Treatment of mice with different doses of BER or SASP significantly decreased DAI, MPO activity and MDA content, improved histological changes of colon tissues, blunted the expressions of NF-κB p65 and ICAM-1 proteins, and enhanced SOD activity. Conclusion Berberine chloride has excellent therapeutic effect on ulcerative colitis caused by DSS in mice. The possible mechanism may be related to its antioxidant and anti-inflammatory activities associated with inhibiting the NF-κB activation and ICAM-1 expression.

顺磁纳米颗粒经AEAPS及Dextran生物修饰后标记MSCs

目的对超顺磁纳米颗粒(SPION)进行AEAPS及Dextran共修饰以增强其生物相容性,探讨生物修饰后的SPI-ON标记间充质干细胞(MSCs)的方法及合适条件。方法共沉淀一步法制备SPION,并进行AEAPS与Dextran共修饰,检测其性质。从大鼠骨髓中获得MSCs,进行SPION标记,利用普鲁士蓝染色、锥虫蓝染色和MTT实验分别检测标记细胞的效率、活性和增殖情况,并确定标记的合适条件。结果制得的SPION经生物修饰后稳定、均匀,具有超顺磁性,在30μg/mL的浓度时细胞标记率达到100%,且标记细胞的活性、增殖能力与对照组比较差异无统计学意义(P>0.05)。而未经生物修饰的SPION在此浓度下的细胞标记率为67.2%,且标记细胞的活性和增殖受到显著性影响(P<0.05)。结论经AEAPS与Dextran修饰,增加了SPION的生物相容性,可对MSCs进行标记,标记的合适浓度为30μg/mL。

基于Au_(nano)-PB、AEAPS-Dextran-Fe_3O_4和Au_(nano)修饰的前列腺特异性抗原电流型免疫传感器的研究

目的采用普鲁士兰-纳米金(Au_(nano)-PB)、氨基硅烷化-葡聚糖-四氧化三铁纳米复合物(AEAPS-Dextran-Fe_3O_4)及纳米金(Aunano)共修饰于氧化铟锡(ITO)电极表面固载抗体制得高灵敏前列腺特异性抗原电流型免疫传感器。方法先将ITO电极表面滴加适量Au_(nano)-PB,随后将AEAPS-Dextran-Fe_3O_4滴涂在ITO玻璃电极的Au_(nano)-PB膜上,然后通过静电吸附Au-nano并固定前列腺特异性抗体(anti-PSA),制得电流型免疫传感器。结果在最佳实验条件下,该传感器响应的峰电流值与前列腺特异性抗原(PSA)浓度在该传感器(0.8～20)ng/mL及(20～170)ng/mL的范围内保持良好的线性关系,检测下限为0.6ng/mL。结论成功建立了前列腺特异性抗原免疫传感器,该方法制备简单,操作便捷,检测下限低。

^(99m)Tc—Dextran淋巴显像在恶性淋巴瘤诊断和治疗中的临床应用

本文探讨了^(99m)Tc—Dextran淋巴显像在恶性淋巴瘤诊断和治疗中的应用.结果表明:(1)^(99m)Tc—Dextran淋巴显像有一定可靠性,对恶性淋巴瘤临床分期有较好应用价值,特别对腹膜后淋巴瘤更为重要,本组63.5%病人改变了临床分期,可指导临床治疗和判断疗效.(2)^(99m)Tc—Dextran淋巴显像可确定淋巴瘤所在淋巴链中位置,同时对检测淋巴回流也是一种较好的方法.(3)本方法不需破坏淋巴管,因此也是淋巴管内注入抗癌药物必要的筛选手段.

犬脾梗死量与栓塞剂Dextran量和脾血流量关系的实验研究

目的 探讨栓塞材料Dextran微球 (SephadexG5 0 )剂量与脾梗死量及脾动脉血流量变化的关系。方法 15只成年杂种犬分为 5个剂量组 ,即 5 0、10 0、15 0mg组各 3只 ,2 0 0mg组 4只 ,2 5 0mg组 2只。脾栓塞前后用电磁血流计测脾动脉血流量 ,脾动脉造影。用体视学方法测量脾梗死量。结果 栓塞剂SephadexG5 0剂量与脾梗死量有非常显著的线性正相关 (r =0 888,P <0 0 0 1) ,栓塞剂量与脾动脉血流减少量也有非常显著的线性关系 (r =0 869,P <0 0 0 1) ,脾梗死量与脾动脉血流减少量有非常明显的平行变化趋势 (r=0 794,P <0 0 0 1)。结论 探索栓塞剂量与脾梗死量之间的关系的影响因素 ,有可能实现通过栓塞剂量来预测脾梗死量 ;血流量的变化可反映脾梗死量 。

兔眼葡萄膜巩膜引流术后FITC-Dextran在眼组织中的分布

目的观察兔眼葡萄膜巩膜引流术后房水流出道的形态学改变。方法 20只中国白兔随机分为2组,一组行葡萄膜巩膜引流术,另一组行小梁切除术,均行右眼手术。术后2周术眼前房内灌注异硫氰酸荧光素标记的葡聚糖(FITC-Dextran),处死后取完整眼球做冰冻切片,在激光共聚焦显微镜下观察荧光素的分布。与手术部位处在眼环同一子午线上的同眼的对称部位未手术眼组织作为对照。结果在葡萄膜巩膜引流术组,荧光素的分布在前、中部巩膜最强,前葡萄膜次之;而在小梁切除术组,荧光素的分布在前葡萄膜最强,前、中部巩膜次之,两组的后葡萄膜和后巩膜均有部分中等亮度的显影,对照组的后葡萄膜和后巩膜则几乎无显影,且两组的前、中部巩膜荧光素强度均明显高于对照组。结论葡萄膜巩膜引流术和小梁切除术术后房水引流均是多途径的,既有外滤过,还增强了葡萄膜巩膜引流。与小梁切除术相比,葡萄膜巩膜引流术还明显增加了跨巩膜引流。

单抗导向药物3A1-Dextran-DM对白血病CEM细胞特异性杀伤效应的观察

抗T淋巴母细胞单克隆抗体与柔红霉素的结合物,在体外对T淋巴母细胞CEM显示出选择性杀伤作用,而对K562、Raji、SP2/0等非T淋巴细胞则无杀伤效应。由此证实单抗3Al-柔红霉素免疫结合物具有导向杀伤癌细胞的性能,为临床特异性治疗肿瘤带来了新的希望。

Research Progress in Formation and Detection Method of Dextran in Sugarcane Production

Dextran in sugarcane production process is formed by Leuconostoc rnesenteroides. The content levels of dextran is related to sugarcane varieties, field condition （planting pattern, temperature, humidity, sunlight, soil, foreign material）, de- gree of injury （refractory cane, harvesting methods）, and can be rapidly and accu- rately measured by Dextran Immunonephelometric Test Kit. The presence of dextran indicates that sucrose has been lost, so sugarcane dextran is a direct and reliable indicator to measure sugarcane freshness and quality.

Dextran sodium sulfate colitis murine model: An indispensable tool for advancing our understanding of inflammatory bowel diseases pathogenesis

Inflammatory bowel diseases(IBD),including Crohn's disease and ulcerative colitis,are complex diseases that result from the chronic dysregulated immune response in the gastrointestinal tract. The exact etiology is not fully understood,but it is accepted that it occurs when an inappropriate aggressive inflammatory respon-se in a genetically susceptible host due to inciting environmental factors occurs. To investigate the path-ogenesis and etiology of human IBD,various animal models of IBD have been developed that provided indispensable insights into the histopathological and morphological changes as well as factors associated with the pathogenesis of IBD and evaluation of therapeutic options in the last few decades. The most widely used experimental model employs dextran sodium sulfate(DSS) to induce epithelial damage. The DSS colitis model in IBD research has advantages over other various chemically induced experimental models due to its rapidity,simplicity,reproducibility and controllability. In this manuscript,we review the newer publicized advances of research in murine colitis models that focus upon the disruption of the barrier function of the intestine,effects of mucin on the development of colitis,alterations found in microbial balance and resultant changes in the metabolome specifically in the DSS colitis murine model and its relation to the pathogenesis of IBD.

Negative impact of bone-marrow-derived mesenchymal stem cells on dextran sulfate sodium-induced colitis

AIM:To investigate the effects of mesenchymal stem cells(MSCs)on dextran sulfate sodium-induced inflammatory bowel disease(IBD).METHODS:C57BL/6 mice were fed 3.5%(g/L)dextran sulfate sodium.On day seven,the mice received intraperitoneal injections of 1×106 MSCs.The survival rate,disease activity index values,and body weight,were monitored daily.On day ten,colon lengths and histopathologic changes were assessed.In addition,immunoregulatory changes following MSC administration were evaluated by determining the levels of effector T cell responses in the spleen and mesenteric lymph nodes,and the expression levels of inflammatory cytokines in homogenized colons.RESULTS:Intraperitoneal administration of MSCs did not prevent development of colitis and did not reduce the clinicopathologic severity of IBD.No significant difference was evident in either survival rate or disease activity index score between the control and MSCtreated group.Day ten-sacrificed mice exhibited no significant difference in either colon length or histopathologic findings.Indeed,the MSC-treated group exhibited elevated levels of interleukin(IL)-6 and transforming growth factor-β,and a reduced level of IL-10,in spleens,mesenteric lymph nodes,and homogenized colons.The IL-17 level was lower in the mesenteric lymph nodes of the MSC-treated group(P=0.0126).In homogenized colons,the IL-17 and tumor necrosis factor-α(P=0.0092)expression levels were also lower in the treated group.CONCLUSION:MSC infusion provided no significanthistopathologic or clinical improvement,thus representing a limited therapeutic approach for IBD.Functional enhancement of MSCs is needed in further study.

Temporal clinical, proteomic, histological and cellular immune responses of dextran sulfate sodium-induced acute colitis

AIM To investigate the temporal clinical, proteomic, histological and cellular immune profiles of dextran sulfate sodium(DSS)-induced acute colitis.METHODS Acute colitis was induced in C57 BL/6 female mice by administration of 1%, 2% or 3% DSS in drinking water for 7 d. Animals were monitored daily for weight loss, stool consistency and blood in the stool, while spleens and colons were harvested on day 8. A time course analysis was performed in mice ingesting 3% DSS, which included colon proteomics through multiplex assay, colon histological scoring by a blinded investigator, and immune response through flow cytometry or immunohistochemistry of the spleen, mesenteric lymph node and colon.RESULTS Progressive worsening of clinical colitis was observed with increasing DSS from 1% to 3%. In mice ingesting 3% DSS, colon shortening and increase in proinflammatory factors starting at day 3 was observed, with increased spleen weights at day 6 and day 8. This coincided with cellular infiltration in the colon from day 2 to day 8, with progressive accumulation of macrophages F4/80^+, T helper CD4^+(Th), T cytotoxic CD8^+(Tcyt) and T regulatory CD25^+(Treg) cells, and progressive changes in colonic pathology including destruction of crypts, loss of goblet cells and depletion of the epithelial barrier. Starting on day 4, mesenteric lymph node and/or spleen presented with lower levels of Treg, Th and Tcyt cells, suggesting an immune cell tropism to the gut. CONCLUSION These results demonstrate that the severity of experimental colitis is dependent on DSS concentration, correlated with clinical, proteomic, histological and cellular immune response on 3% DSS.

Suppressive effect of pectic polysaccharides extracted from Rauwolfia verticillata(Lour.) Baill.var.hainanensis Tsiang on inflammation by regulation of NF-κB pathway and interleukin-17 in mice with dextran sulphatesodium-induced ulcerative colitis

Objective:To investigate the effects of pectic polysaccharides extracted from Rauwolfia verticillata(Lour.) Baill.var.hainanensis Tsiang on an experimental murine colitis model.Methods:Experimental colitis was induced by dextran sulfate sodium(DSS),and mice were divided into 4 groups:control.DSS alone.DSS plus SASP,DSS plus pectic polysaccharides.The disease activity index(DAI) and histological score were observed.The tumor necrosis factor(TNF)-α and interleukin(IL)-17 levels were measured by enzyme-linked immunosorbent assay.I κ B and NF-κB p65 expression were assessed by western blot analysis.Myeloperoxidase(MPO) activity was determined by using MPO assay kit.Re.sults:Administration of pectic polysaccharides significantly reduced the severity of DSS-induced colitis as assessed by DAT and histological score,and resulted in down regulation of MPO activity and NF-κB p65 expression and subsequent degradation of IκB protein,strikingly reduced the production of TNF-α and IL-17.Conclusions:Pectic polysaccharides extracted from Rauvolfia verticillata(Lour.)Baill.var.hainanensis Tsiang exerts beneficial effects in experimental colitis and may therefore provide a useful therapeutic approach for the treatment of UC.

益肾止血颗粒对Dextran诱发大鼠肠系膜急性微循环障碍的影响

目的探讨益肾止血颗粒对Dextran诱发大鼠肠系膜急性微循环障碍的改善作用。方法大鼠50只随机分成对照组,阳性对照组(肾炎康复片10.8 g/kg)和益肾止血颗粒13.5 g/kg、6.75 g/kg、3.4 g/kg 3个剂量组。试验共分5组,每组10只。灌胃给药1 h后,以10%Dextran 6 mL/kg舌静脉给药,制备急性微循环障碍模型。通过微循环显微镜和微图像计算机处理装置观察记录肠系膜注射Dextran 0、5、15、30、45、60 min的微动脉流速、微静脉流速、微动脉血管口径、微静脉血管口径、毛细血管开放数和微静脉血流状态的变化。结果在注射Dextran后5、15、30、45、60 min时,益肾止血颗粒能增快微血管血流速度,与对照组比较有显著差异性(P<0.01或P<0.05);注射Dextran后30、45、60 min,益肾止血颗粒能显著改善微血管痉挛状态,微动脉、微静脉血管口径与对照组比较均有显著差异性(P<0.01或P<0.05);注射Dextran后45、60 min,益肾止血颗粒能显著增加毛细血管开放数,毛细血管开放数与对照组比较均有显著差异性(P<0.05);益肾止血颗粒在注射Dextran后15、30、45、60 min,可以明显改善微循环血液流态,与对照组比较均有显著差异性(P<0.01或P<0.05)。结论益肾止血颗粒可以明显改善大鼠肠系膜微循环障碍。

Kefir treatment ameliorates dextran sulfate sodium-induced colitis in rats

AIM: To investigate the preventive effect of kefir on colitis induced with dextran sulfate sodium(DSS) in rats.METHODS: Twenty-four male Wistar-albino rats were randomized into four groups: normal control,kefircontrol,colitis,and kefir-colitis groups. Rats in the normal and kefir-control groups were administered tap water as drinking water for 14 d. Rats in the colitis and kefir-colitis groups were administered a 3% DSS solution as drinking water for 8-14 d to induce colitis. Rats in the kefir-control and kefir-colitis groups were administered 5 m L kefir once a day for 14 d while rats in the normal control and colitis group were administered an identical volume of the placebo(skim milk) using an orogastric feeding tube. Clinical colitis was evaluated with reference to the disease activity index(DAI),based on daily weight loss,stool consistency,and presence of bleeding in feces. Rats were sacrificed on the 15 th day,blood specimens were collected,and colon tissues were rapidly removed. Levels of myeloperoxidase(MPO),tumor necrosisfactor(TNF)-α,interleukin(IL)-10,malondialdehyde,and inducible nitric oxide synthase(i NOS) were measured in colon tissue.RESULTS: The DAI was lower in the kefir-colitis group than in the colitis group(on the 3rd and 5th days of colitis induction; P < 0.01). The DAI was also significantly higher in the colitis group between days 2 and 6 of colitis induction when compared to the normal control and kefir-control groups. The DAI was statistically higher only on the 6th day in the kefircolitis group when compared to that in the normal control groups. Increased colon weight and decreased colon length were observed in colitis-induced rats. Mean colon length in the colitis group was significantly shorter than that of the kefir-control group. Kefir treatment significantly decreased histologic colitis scores(P < 0.05). MPO activity in the colitis group was significantly higher than in the kefir-control group(P < 0.05). Kefir treatment significantly reduced the DSS colitis-induced TNF-α increase(P < 0.01). No statistically significant differences were observed among groups for IL-10 and MDA levels. Colon tissue i NOS levels in the colitis group were significantly higher than those in the control and kefir-colitis groups(P < 0.05).CONCLUSION: Kefir reduces the clinical DAI and histologic colitis scores in a DSS-induced colitis model,possibly via reduction of MPO,TNF-α,and i NOS levels.