Semaphorin 7A impairs barrier function in cultured human corneal epithelial cells in a manner dependent on nuclear factor-kappa B

●AIM:To evaluate the role of semaphorin 7A(Sema7A)and its associated regulatory mechanisms in modulating the barrier function of cultured human corneal epithelial cells(HCEs).●METHODS:Barrier models of HCEs were treated with recombinant human Sema7A at concentrations of 0,125,250,or 500 ng/mL for 24,48,or 72h in vitro.Transepithelial electrical resistance(TEER)as well as Dextran-fluorescein isothiocyanate(FITC)permeability assays were conducted to assess barrier function.To quantify tight junctions(TJs)such as occludin and zonula occludens-1(ZO-1)at the mRNA level,reverse transcriptionpolymerase chain reaction(RT-PCR)analysis was performed.Immunoblotting was used to examine the activity of the nuclear factor-kappa B(NF-κB)signaling pathway and the production of TJs proteins.Immunofluorescence analyses were employed to localize the TJs.Enzyme-linked immunosorbent assay(ELISA)and RT-PCR were utilized to observe changes in interleukin(IL)-1βlevels.To investigate the role of NF-κB signaling activation and IL^(-1)βin Sema7A’s anti-barrier mechanism,we employed 0.1μmol/L IκB kinase 2(IKK2)inhibitor IV or 500 ng/mL IL^(-1)receptor(IL-1R)antagonist.●RESULTS:Treatment with Sema7A resulted in decreased TEER and increased permeability of Dextran-FITC in HCEs through down-regulating mRNA and protein levels of TJs in a time-and dose-dependent manner,as well as altering the localization of TJs.Furthermore,Sema7A stimulated the activation of inhibitor of kappa B alpha(IκBα)and expression of IL-1β.The anti-barrier function of Sema7A was significantly suppressed by treatment with IKK2 inhibitor IV or IL-1R antagonists.●CONCLUSION:Sema7A disrupts barrier function through its influence on NF-κB-mediated expression of TJ proteins,as well as the expression of IL-1β.These findings suggest that Sema7A could be a potential therapeutic target for the diseases in corneal epithelium.

Jianpi Gushen Huayu decoction ameliorated diabetic nephropathy through modulating metabolites in kidney,and inhibiting TLR4/NF-κB/NLRP3 and JNK/P38 pathways

BACKGROUND Jianpi Gushen Huayu Decoction(JPGS)has been used to clinically treat diabetic nephropathy(DN)for many years.However,the protective mechanism of JPGS in treating DN remains unclear.AIM To evaluate the therapeutic effects and the possible mechanism of JPGS on DN.METHODS We first evaluated the therapeutic potential of JPGS on a DN mouse model.We then investigated the effect of JPGS on the renal metabolite levels of DN mice using non-targeted metabolomics.Furthermore,we examined the effects of JPGS on c-Jun N-terminal kinase(JNK)/P38-mediated apoptosis and the inflammatory responses mediated by toll-like receptor 4(TLR4)/nuclear factor-kappa B(NF-κB)/NOD-like receptor family pyrin domain containing 3(NLRP3).RESULTS The ameliorative effects of JPGS on DN mice included the alleviation of renal injury and the control of inflammation and oxidative stress.Untargeted metabolomic analysis revealed that JPGS altered the metabolites of the kidneys in DN mice.A total of 51 differential metabolites were screened.Pathway analysis results indicated that nine pathways significantly changed between the control and model groups,while six pathways significantly altered between the model and JPGS groups.Pathways related to cysteine and methionine metabolism;alanine,tryptophan metabolism;aspartate and glutamate metabolism;and riboflavin metabolism were identified as the key pathways through which JPGS affects DN.Further experimental validation showed that JPGS treatment reduced the expression of TLR4/NF-κB/NLRP3 pathways and JNK/P38 pathway-mediated apoptosis related factors.CONCLUSION JPGS could markedly treat mice with streptozotocin(STZ)-induced DN,which is possibly related to the regulation of several metabolic pathways found in kidneys.Furthermore,JPGS could improve kidney inflammatory responses and ameliorate kidney injuries in DN mice via the TLR4/NF-κB/NLRP3 pathway and inhibit JNK/P38 pathwaymediated apoptosis in DN mice.

Delayed hepatocarcinogenesis through antiangiogenic intervention in the nuclear factor-kappa B activation pathway in rats

BACKGROUND: The active form of nuclear factor-kappa B (NF-kappa B) is involved in the initiation, generation, and development of hepatocellular carcinoma (HCC), and is up-regulated in inflammation-associated malignancies. We investigated the dynamic expression of NF-kappa B and its influences on the occurrence of HCC through antiangiogenic (thalidomide) intervention in NF-kappa B activation. METHODS : Hepatoma models were induced with 2-fluorenylacetamide (2-FAA, 0.05%) in male Sprague-Dawley rats, and thalidomide (100 mg/kg body weight) was administered intragastrically to intervene in NF-kappa B activation. The pathological changes in the liver of sacrificed rats were assessed after hematoxylin and eosin staining. NF-kappa B mRNA was amplified by RT-nested PCR. The alterations of NF-kappa B and vascular endothelial growth factor (VEGF) expression were analyzed by enzyme-linked immunosorbent assay, immunohistochemistry, and Western blotting. RESULTS: Rat hepatocytes showed denatured, precancerous, and cancerous stages in hepatocarcinogenesis, with an increasing tendency of hepatic NF-kappa B, NF-kappa B mRNA, and VEGF expression, and their values in the HCC group were higher than those in controls (P<0.001). In the thalidomide-treated group, the morphologic changes generated only punctiform denaturation and necrosis at the early or middle stages, and nodular hyperplasia or a little atypical hyperplasia at the final stages, with the expression of NF-kappa B (chi(2)=9.93, P<0.001) and VEGF (chi(2)=8.024, P<0.001) lower than that in the 2-FAA group. CONCLUSION: NF-kappa B is overexpressed in hepatocarcinogenesis and antiangiogenic treatment down-regulates the expression of NF-kappa B and VEGF, and delays the occurrence of HCC. (Hepatobiliary Pancreat Dis Int 2010; 9: 169-174)

Urinary trypsin inhibitor attenuates hepatic ischemia-reperfusion injury by reducing nuclear factor-kappa B activation

BACKGROUND: Urinary trypsin inhibitor (UTI) inhibits the inflammatory response and protects against ischemia-reperfusion (I/R) injury. The inflammatory response is mediated by nuclear factor-kappa B (NF-kappa B) and its related target genes and products such as vascular endothelial cell adhesion molecule and CXC chemokines. We aimed to assess the roles of those mediators in a UTI-treated mouse model of hepatic I/R injury. METHODS: Treatment group 1 (UTI given 5 minutes prior to liver ischemia), treatment group 2 (UTI given 5 minutes after the anhepatic phase) and a control group were investigated. Blood and liver samples were obtained and compared at 1, 3, 6 and 24 hours after reperfusion. RESULTS: Attenuation of pathological hepatocellular damage was greater in the treatment groups than in the control group (P < 0.05). Compared with the control group, the UTI treatment groups showed significantly lower serum alanine aminotransferase and aspartate aminotransferase levels, decreased myeloperoxidase activity, and reduced NF-kappa B activation. Also downregulated was the expression of tumor necrosis factor-alpha, cytokine-induced neutrophil chemoattractant, and macrophage inflammatory protein-2 at the mRNA level. P-selectin protein and intercellular adhesion molecule-1 protein expression were also downregulated. In addition, the treatment group I showed a better protective effect against I/R injury than the treatment group 2. CONCLUSIONS: UTI reduces NF-kappa B activation and downregulates the expression of its related mediators, followed by the inhibition of neutrophil aggregation and infiltration in hepatic I/R injury. The protective role of UTI is more effective in prevention than in treatment.

Characteristics of hepatic nuclear-transcription factor-kappa B expression and quantitative analysis in rat hepatocarcinogenesis

BACKGROUND: Hepatocellular carcinoma (HCC) is one of the most common malignant tumors. We analyzed the expression of miclear-transcription factor-kappa B (NF-kappa B) during hepatocarcinogenesis in order to evaluate its dynamic expression and its clinical value in the development and diagnosis of HCC. METHODS: Hepatoma models were induced by oral administration of 2-acetamidoflurene (2-FAA) to male Sprague-Dawley rats. Morphological changes were observed after hematoxylin and eosin staining. The cellular distribution of NF-kappa B expression during different stages of cancer development was investigated by immunohistochemistry, and the level of NF-kappa B expression in liver tissues was quantitatively analyzed by ELISA. The gene fragments of hepatic NF-kappa B were amplified by nested-polymerase chain reaction assay. RESULTS: Hepatocytes showed vacuole-like degeneration during the early stages, then had a hyperplastic nodal appearance during the middle stages, and finally progressed to tubercles of cancerous nests with high differentiation. The NF-kappa B-positive material was buff-colored, fine particles localized in the nucleus, and the incidence of NF-kappa B-positive cells was 81.8% in degeneration, 83.3% in precancerous lesions, and 100% in cancerous tissues. All of these values were higher than those in controls (P<0.01). Hepatic NF-kappa B expression and hepatic NF-kappa B-mRNA were also higher during the course of HCC development (P<0.01). CONCLUSION: The NF-kappa B signal transduction pathway is activated during the early stages of HCC development, and its abnormal expression may be associated with the occurrence of HCC.

Dietary saturated fatty acid and polyunsaturated fatty acid oppositely affect hepatic NOD-like receptor protein 3 inflammasome through regulating nuclear factor-kappa B activation

AIM: To investigate the effect of different dietary fatty acids on hepatic inflammasome activation.METHODS: Wild-type C57BL/6 mice were fed either a high-fat diet or polyunsaturated fatty acid (PUFA)-enriched diet. Primary hepatocytes were treated with either saturated fatty acids (SFAs) or PUFAs as well as combined with lipopolysaccharide (LPS). The expression of NOD-like receptor protein 3 (NLRP3) inflammasome, peroxisome proliferator-activated receptor-&#x003b3; and nuclear factor-kappa B (NF-&#x003ba;B) was determined by real-time PCR and Western blot. The activity of Caspase-1 and interleukine-1&#x003b2; production were measured.RESULTS: High-fat diet-induced hepatic steatosis was sufficient to induce and activate hepatic NLRP3 inflammasome. SFA palmitic acid (PA) directly activated NLRP3 inflammasome and increased sensitization to LPS-induced inflammasome activation in hepatocytes. In contrast, PUFA docosahexaenoic acid (DHA) had the potential to inhibit NLRP3 inflammasome expression in hepatocytes and partly abolished LPS-induced NLRP3 inflammasome activation. Furthermore, a high-fat diet increased but PUFA-enriched diet decreased sensitization to LPS-induced hepatic NLRP3 inflammasome activation in vivo. Moreover, PA increased but DHA decreased phosphorylated NF-&#x003ba;B p65 protein expression in hepatocytes.CONCLUSION: Hepatic NLRP3 inflammasome activation played an important role in the development of non-alcoholic fatty liver disease. Dietary SFAs and PUFAs oppositely regulated the activity of NLRP3 inflammasome through direct activation or inhibition of NF-&#x003ba;B.

Testosterone alleviates tumor necrosis factor-alpha-mediated tissue factor pathway inhibitor downregulation via suppression of nuclear factor-kappa B in endothelial cells

We have observed earlier that testosterone at physiological concentrations can stimulate tissue factor pathway inhibitor(TFPI)gene expression through the androgen receptor in endothelial cells.This study further investigated the impact of testosterone on TFPI levels in response to inflammatory cytokine tumor necrosis factor-alpha(TNF-α).Cultured human umbilical vein endothelial cells were incubated in the presence or absence of testosterone or TNF-α.TFPI protein and mRNA levels were assessed by enzyme-linked immunosorbent assay and quantitative real-time reverse transcription polymerase chain reaction.To study the cellular mechanism of testosterone’s action,nuclear factor-kappa B(NF-κB)translocation was confirmed by electrophoretic mobility shift assays.We found that after NF-κB was activated by TNF-α,TFPI protein levels declined significantly by 37.3%compared with controls(P<0.001),and the mRNA levels of TFPI also decreased greatly(P<0.001).A concentration of 30 nmol L-1 testosterone increased the secretion of TFPI compared with the TNF-α-treated group.NF-κB DNA-binding activity was significantly suppressed by testosterone(P<0.05).This suggests that physiological testosterone concentrations may exert their antithrombotic effects on TFPI expression during inflammation by downregulating NF-κB activity.

Inhibitory effects of Shuanghuanglian injection on nuclear factor-kappa B expression in mice with viral encephalitis in a time-and dose-dependent manner

Previous studies have confirmed that the anti-virus effects of Shuanghuanglian injection may be associated with nuclear factor-kappa B activity. This study observed nuclear factor-kappa B expression in mice with viral encephalitis, and showed significant decreases in nuclear factor-kappa B protein and mRNA levels following Shuanghuanglian injection. The inhibitory effect was more significant with prolonged intervention duration and increased treatment dose. These findings verify that Shuanghuanglian injection plays a therapeutic role in viral encephalitis by reducing expression of nuclear factor-kappa B in a time- and dose-dependent manner.

Shuanghuanglian injection downregulates nuclear factor-kappa B expression in mice with viral encephalitis

A mouse model of viral encephalitis was induced by intracranial injection of a Coxsackie virus B3 suspension. Quantitative real-time reverse transcription-PCR and western blot assay were applied to detect mRNA and protein expression of intelectin-2 and nuclear factor-kappa B in the viral encephalitis and control groups. Nuclear factor-kappa B and intelectin-2 mRNA and protein expression were significantly increased in mice with viral encephalitis. After intraperitoneal injection of Shuanghuanglian at a dose of 1.5 mg/kg for 5 successive days, intelectin-2 and nuclear factor-kappa B protein and mRNA expression were significantly decreased. To elucidate the relationship between intelectin-2 and nuclear factor-kappa B, mice with viral encephalitis were administered an intracerebral injection of 107 pfu recombinant lentivirus expressing intelectin shRNA. Both protein and mRNA levels of intelectin and nuclear factor-kappa B in brain tissue of mice were significantly decreased. Experimental findings suggest that Shuanghuanglian injection may downregulate nuclear factor-kappa B production via suppression of intelectin production, thus inhibiting inflammation associated with viral encephalitis.

Effects of Five Chitosan Oligosaccharides on Nuclear Factor-kappa B Signaling Pathway

The effects of five chito-oligomers, from dimer to hexamer （chitobiose, chitotriose, chitotetraose, chitopentaose, chitohexaose） separated from chitosan oligosaccharides, on nuclear factor -kappaB （NF-rd3） signaling pathway were investigated by using luciferase assay and laser scanning microscopy. The expression of NF-rd3 downstream genes （cyclin DI, TNFa and IL-6） were tested by real time PCR. We found that all five chitosan oligosaccharides increased NF-KB-dependent luciferase gene expression and NF-KB downstream genes transcription, and the most significant were chitotetraose and chitohexaose. In addition, laser scanning microscopy experiments showed that chitotetraose and chitohexaose also activated the p65 subunite of NF-kB translocating from cytoplasm to nucleus, which suggested that they were the most potent activators of NF-kB signaling pathway.

Ketogenic diet alleviates cognitive dysfunction and neuroinflammation in APP/PS1 mice via the Nrf2/HO-1 and NF-κB signaling pathways

Alzheimer's disease is a progressive neurological disorder characterized by cognitive decline and chronic inflammation within the brain.The ketogenic diet,a widely recognized therapeutic intervention for refractory epilepsy,has recently been proposed as a potential treatment for a variety of neurological diseases,including Alzheimer's disease.However,the efficacy of ketogenic diet in treating Alzheimer's disease and the underlying mechanism remains unclear.The current investigation aimed to explore the effect of ketogenic diet on cognitive function and the underlying biological mechanisms in a mouse model of Alzheimer's disease.Male amyloid precursor protein/presenilin 1(APP/PS1)mice were randomly assigned to either a ketogenic diet or control diet group,and received their respective diets for a duration of 3 months.The findings show that ketogenic diet administration enhanced cognitive function,attenuated amyloid plaque formation and proinflammatory cytokine levels in APP/PS1 mice,and augmented the nuclear factor-erythroid 2-p45 derived factor 2/heme oxygenase-1 signaling pathway while suppressing the nuclear factor-kappa B pathway.Collectively,these data suggest that ketogenic diet may have a therapeutic potential in treating Alzheimer's disease by ameliorating the neurotoxicity associated with Aβ-induced inflammation.This study highlights the urgent need for further research into the use of ketogenic diet as a potential therapy for Alzheimer's disease.

Effects of transplantation of microencapsulated rabbit sciatic nerve on nuclear factor-kappa B expression after spinal cord injury in rats

BACKGROUND： It has been reported that nuclear factor-kappa B （NF- κB）, activated after spinal cord injury in rats, plays a key role in inflammatory responses in the central nervous system. OBJECTIVE： To investigate the effects of transplantation of microencapsulated rabbit sciatic nerve on NF- κB expression and motor function after spinal cord injury in rats, and to compare the results with the transplantation of rabbit sciatic nerve alone. DESIGN, TIME AND SETTING： This completely randomized, controlled study was performed at the Department of Neurobiology, Medical College of Nanchang University between December 2007 and July 2008. MATERIALS： A rabbit anti-NF- κB P65 monoclonal antibody was made by the Santa Cruz Company, USA and a streptavidin peroxidase immunohistochemical kit was provided by the Sequoia Company, China. METHODS： Eight rabbits were used to prepare a sciatic nerve cell suspension that was divided into two parts： one stored for transplantation, and the other mixed with a 1.5% sodium alginate solution. One hundred and twenty adult Sprague Dawley rats weighing 220-250 g were randomly divided into four groups： the microencapsulated cell group （n = 36）, the non-encapsulated cell group （n = 36）, the saline group （n = 36） and the sham operation group （n = 12）. The first three groups underwent a right hemisection injury of the spinal cord at the T10 level, into which was transplanted a gelatin sponge soaked with 10 μL of a microencapsulated nerve tissue/cell suspension （microencapsulated cell group）, a tissue/cell suspension （non-encapsulated cell group） or physiological saline （saline group）. In the sham operation group the vertebrae were exposed, but the spinal cord was not injured, and no implantation was given. MAIN OUTCOME MEASURES： Pathological changes were detected using hematoxylin-eosin staining; NF- κB expression was quantified using immunohistochemical staining; motor function was assessed using the Basso, Beattie and Bresnahan （BBB） scale. RESULTS： Spinal cord injuries, such as neuronal death and inflammatory cell infiltration, were found in the microencapsulated cell group, the non-encapsulated cell group and the saline group. However, the damage in the microencapsulated cell group was milder than in the non-encapsulated cell or saline groups. NF- κB expression in the microencapsulated cell group, the non-encapsulated cell group and the saline group was increased after spinal cord injury; it reached a peak after 24 hours, gradually decreased after 3 days, and was close to normal levels after 7 days. NF- κB expression in the microencapsulated cell group was significantly lower than in the saline group and the non-encapsulated cell group （P 〈 0.05）. With time, the motor function of the animals in each group improved to a certain extent, but did not reach normal levels. There were no significant differences in BBB scores between the different groups on post-operative day 3; however, the BBB scores for the microencapsulated cell group and the non-encapsulated cell group were significantly higher than the saline group on post-operative day 7 （P 〈 0.05）. In addition, the motor function recovered better in the microencapsulated cell group than in the non-encapsulated cell group （P 〈 0.05）. CONCLUSION： The transplantation of microencapsulated rabbit sciatic nerve can inhibit NF- κB expression and inflammatory reactions and promote recovery of motor function after spinal cord injury in rats. The effects of microencapsulated cell transplantation are superior to those of transplantation of cells alone.

L-and T-type Ca^(2+)channels dichotomously contribute to retinal ganglion cell injury in experimental glaucoma

Retinal ganglion cell apoptotic death is the main pathological characteristic of glaucoma,which is the leading cause of irreversible blindness.Disruption of Ca^(2+)homeostasis plays an important role in glaucoma.Voltage-gated Ca^(2+)channel blockers have been shown to improve vision in patients with glaucoma.However,whether and how voltage-gated Ca^(2+)channels are involved in retinal ganglion cell apoptotic death are largely unknown.In this study,we found that total Ca^(2+)current densities in retinal ganglion cells were reduced in a rat model of chronic ocular hypertension experimental glaucoma,as determined by whole-cell patch-clamp electrophysiological recordings.Further analysis showed that L-type Ca^(2+)currents were downregulated while T-type Ca^(2+)currents were upregulated at the later stage of glaucoma.Western blot assay and immunofluorescence experiments confirmed that expression of the Ca_(V)1.2 subunit of L-type Ca^(2+)channels was reduced and expression of the Ca_(V)3.3 subunit of T-type Ca^(2+)channels was increased in retinas of the chronic ocular hypertension model.Soluble tumor necrosis factor-α,an important inflammatory factor,inhibited the L-type Ca^(2+)current of isolated retinal ganglion cells from control rats and enhanced the T-type Ca^(2+)current.These changes were blocked by the tumor necrosis factor-αinhibitor XPro1595,indicating that both types of Ca^(2+)currents may be mediated by soluble tumor necrosis factor-α.The intracellular mitogen-activated protein kinase/extracellular signal-regulated kinase pathway and nuclear factor kappa-B signaling pathway mediate the effects of tumor necrosis factor-α.TUNEL assays revealed that mibefradil,a T-type calcium channel blocker,reduced the number of apoptotic retinal ganglion cells in the rat model of chronic ocular hypertension.These results suggest that T-type Ca^(2+)channels are involved in disrupted Ca^(2+)homeostasis and apoptosis of retinal ganglion cells in glaucoma,and application of T-type Ca^(2+)channel blockers,especially a specific CaV3.3 blocker,may be a potential strategy for the treatment of glaucoma.

肾衰泻浊丸对单侧输尿管梗阻大鼠肾组织核转录因子κB与肝细胞生长因子及骨桥蛋白mRNA表达的影响

目的:通过研究中药复方——肾衰泻浊丸对单侧输尿管梗阻(UUO)大鼠肾间质核转录因子κB(NF-κB)、骨桥蛋白(OPN)、肝细胞生长因子(HGF)表达的影响,探讨其抗肾间质纤维化的机制。方法:建立UUO大鼠模型,72只成年雄性Wistar大鼠随机分为假手术组、模型组、贝那普利组及肾衰泻浊丸低、中、高剂量组。在不同的时间点(14、21、28d)检测每组4只实验大鼠治疗后的血清尿素氮(BUN)、肌酐(Scr)变化。观察梗阻侧肾脏病理变化;采用免疫组化法检测肾组织中的NF-κB、HGF及OPN的表达;RT-PCR法检测肾组织中OPNmRNA的表达水平。结果:与假手术组相比,模型组大鼠血清BUN、Scr水平、NF-κB、OPN表达显著升高,HGF表达减少差异有统计学意义(P<0.01,P<0.05);与模型组相比,各治疗组血BUN、Scr水平、NF-κB、OPN表达均显著降低,HGF表达均有所增多差异有统计学意义(P<0.01,P<0.05)。肾衰泻浊丸能够明显降低UUO大鼠血BUN、Scr水平,减轻肾间质损伤,明显下调肾组织中NF-κB和OPN的表达、上调HGF的表达,与贝那普利组比较差异有统计学意义(P<0.01,P<0.05)。结论:肾衰泻浊丸可能通过改善肾功能、抑制NF-κB、OPN的表达、诱导HGF的高表达,从而改善肾间质纤维化。

siRNA阻断NF-κB信号通路抑制胃癌SGC-7901细胞的增殖及侵袭

目的采用RNA干扰(RNA interference,RNAi)技术下调胃癌细胞株SGC-7901中NF-κB p65基因的表达,探讨其对肿瘤细胞增殖活性和侵袭能力的影响。方法利用阳离子脂质体LipofectamineTM2000将化学合成的人NF-κB p65的小干扰RNA(small interference RNA,siRNA)转染入胃癌细胞株SGC-7901中。采用RT-PCR法测定细胞内NF-κB p65mRNA的表达;酶联免疫吸附测定法(ELISA)检测NF-κB亚单位p65的DNA结合活性的改变;采用MTT法测定细胞增殖活性的变化;利用Transwell侵袭实验检测细胞体外侵袭能力的变化。结果与对照组比较,化学合成的人NF-κB p65siRNA能有效地抑制SGC-7901细胞中NF-κB p65mRNA的表达(P<0.05);RelAsiRNA组的p65亚单位与DNA结合活性明显低于对照组(P<0.05),并且RelA siRNA组中SGC-7901细胞的体外侵袭力减弱,增殖活性降低。结论特异的siRNA可以有效阻断NF-κB信号通路,影响人胃癌细胞的增殖活性和体外侵袭能力。

核因子-kappa B反义核苷酸对小鼠移植心脏存活时间的影响

目的;设计特定的反义硫代寡聚脱氧核苷酸(ODN)来特异性地抑制小鼠核因子-kappa B(NF-кB)的mRNA,并观察其对小鼠移植心脏存活时间的影响。方法;将30只小鼠随机分成NF-кB反义ODN给药组、碱基错配ODN对照组和未给药组,小鼠心脏移植血管重建后经腹腔缓释泵分别以12.5mg·kg^(-1)·d^(-1)的剂量全身给予NF-кB反义ODN和碱基错配ODN,持续给药14d,而未给药组不给药物。观察受体小鼠移植心脏存活时间;术后d7各组分别处死5只小鼠,测定受体小鼠脾细胞的混合淋巴细胞培养(MLC)和细胞毒T细胞(CTL)活性。结果:给药组小鼠的移植心脏存活时间较对照组和未给药组明显延长 (P<0.05);MLC显示给药组小鼠脾细胞对供体抗原刺激的增殖反应受到抑制(P<0.05);给药组受体小鼠的脾细胞的CTL活性也明显减弱(P<0.05)。结论:NF-кB反义ODN能有效抑制受体对小鼠移植物的细胞免疫反应,使同种异体的心脏移植存活时间延长。

Heme oxygenase-1 prevents liver fibrosis in rats by regulating the expression of PPAR_γ and NF-_κB

AIM:To investigate the effects of heme oxygenase(HO)-1 on liver fibrosis and the expression of peroxisome proliferator-activated receptor gamma(PPARγ) and nuclear factor-kappa B(NF-κB) in rats.METHODS:Sixty Wistar rats were used to construct liver fibrosis models and were randomly divided into 5 groups:group A(normal,untreated),group B(model for 4 wk,untreated),group C(model for 6 wk,untreated),group D [model for 6 wk,treated with zinc protoporphyrin Ⅸ(ZnPP-Ⅸ) from week 4 to week 6],group E(model for 6 wk,treated with hemin from week 4 to week 6).Next,liver injury was assessed by measuring serum alanine aminotransferase(ALT),aspartate aminotransferase(AST) and albumin levels.The degree of hepatic fibrosis was evaluated by measuring serum hyaluronate acid(HA),type Ⅳ collagen(Ⅳ-C) and by histological examination.Hydroxyproline(Hyp) content in the liver homogenate was determined.The expres-sion levels of alpha-smooth muscle actin(α-SMA) in liver tissue were measured by real-time quantitative polymerase chain reaction(RT-PCR).The expression levels of PPARγ and NF-κB were determined by RT-PCR and Western blotting.RESULTS:The expression of HO-1 increased with the development of fibrosis.Induction of HO-1 by hemin significantly attenuated the severity of liver injury and the levels of liver fibrosis as compared with inhibition of HO-1 by ZnPP-Ⅸ.The concentrations of serum ALT,AST,HA and Ⅳ-C in group E decreased compared with group C and group D(P < 0.01).Amount of Hyp and α-SMA in the liver tissues in group E decreased compared with group C(0.62 ± 0.14 vs 0.84 ± 0.07,1.42 ± 0.17 vs 1.84 ± 0.17,respectively,P < 0.01) and group D(0.62 ± 0.14 vs 1.11 ± 0.16,1.42 ± 0.17 vs 2.56 ± 0.37,respectively,P < 0.01).The expression of PPARγ at levels of transcription and translation decreased with the development of fibrosis especially in group D;and it increased in group E compared with groups C and D(0.88 ± 0.15 vs 0.56 ± 0.19,0.88 ± 0.15 vs 0.41 ± 0.11,respectively,P < 0.01).The expression of NF-κB increased with the development of fibrosis especially in group D;and it decreased in group E compared with groups C and D(1.43 ± 0.31 vs 1.89 ± 0.29,1.43 ± 0.31 vs 2.53 ± 0.54,respectively,P < 0.01).CONCLUSION:Our data demonstrate a potential mechanism that HO-1 can prevent liver fibrosis by enhancing the expression of PPARγ and decreasing the expression of NF-κB in liver tissues.

TLR4 upregulates CBS expression through NF-κB activation in a rat model of irritable bowel syndrome with chronic visceral hypersensitivity

AIM:To investigate the roles of toll-like receptor 4(TLR4) and nuclear factor(NF)-κB on cystathionine βsynthetase(CBS) expression and visceral hypersensitivity in rats.METHODS:This study used 1-7-wk-old male SpragueDawley rats.Western blot analysis was employed to measure the expression of TLR4,NF-kB and the endogenous hydrogen sulfide-producing enzyme CBS in colon dorsal root ganglia(DRG) from control and "irritable bowel syndrome" rats induced by neonatal colonic inflammation(NCI).Colon-specific DRG neurons were labeled with Dil and acutely dissociated to measure excitability with patch-clamp techniques.Immunofluorescence was employed to determine the co-expression of TLR4,NF-kB and CBS in Dil-labeled DRG neurons.RESULTS:NCI significantly upregulated the expression of TLR4 in colon-related DRGs(0.34 ± 0.12 vs 0.72 ±0.02 for the control and NCI groups,respectively,P <0.05).Intrathecal administration of the TLR4-selective inhibitor CLI-095 significantly enhanced the colorectal distention threshold of NCI rats.CLI-095 treatment also markedly reversed the hyperexcitability of colonspecific DRG neurons and reduced the expression of CBS(1.7 ± 0.1 vs 1.1 ± 0.04,p < 0.05) and of the NF-kB subunit p65(0.8 ± 0.1 vs 0.5 ± 0.1,P< 0.05).Furthermore,the NF-KB-selective inhibitor pyrrolidine dithiocarbamate(PDTC) significantly reduced the upregulation of CBS(1.0 ± 0.1 vs 0.6 ± 0.1,P< 0.05)and attenuated visceral hypersensitivity in the NCI rats.In vitro,incubation of cultured DRG neurons with the TLR4 agonist lipopolysaccharide significantly enhanced the expression of p65(control vs 8 h:0.9 ± 0.1 vs1.3 ± 0.1;control vs 12 h:0.9 ± 0.1 vs 1.3 ± 0.1,P< 0.05;control vs 24 h:0.9 ± 0.1 vs 1.6 ± 0.1,P <0.01) and CBS(control vs 12 h:1.0 ± 0.1 vs 2.2 ±0.4;control vs 24 h:1.0 ± 0.1 vs 2.6 ± 0.1,P< 0.05),whereas the inhibition of p65 via pre-incubation with PDTC significantly reversed the upregulation of CBS expression(1.2 ± 0.1 vs 0.6 ± 0.0,P< 0.01).CONCLUSION:Our results suggest that the activation of TLR4 by NCI upregulates CBS expression,which is mediated by the NF-kB signaling pathway,thus contributing to visceral hypersensitivity.

Medicinal plant activity on Helicobacter pylori related diseases

More than 50% of the world population is infected with Helicobacter pylori (H. pylori). The bacterium highly links to peptic ulcer diseases and duodenal ulcer, which was classified as a group&#x02005;I&#x02005;carcinogen in 1994 by the WHO. The pathogenesis of H. pylori is contributed by its virulence factors including urease, flagella, vacuolating cytotoxin A (VacA), cytotoxin-associated gene antigen (Cag A), and others. Of those virulence factors, VacA and CagA play the key roles. Infection with H. pylori vacA-positive strains can lead to vacuolation and apoptosis, whereas infection with cagA-positive strains might result in severe gastric inflammation and gastric cancer. Numerous medicinal plants have been reported for their anti-H. pylori activity, and the relevant active compounds including polyphenols, flavonoids, quinones, coumarins, terpenoids, and alkaloids have been studied. The anti-H. pylori action mechanisms, including inhibition of enzymatic (urease, DNA gyrase, dihydrofolate reductase, N-acetyltransferase, and myeloperoxidase) and adhesive activities, high redox potential, and hydrophilic/hydrophobic natures of compounds, have also been discussed in detail. H. pylori-induced gastric inflammation may progress to superficial gastritis, atrophic gastritis, and finally gastric cancer. Many natural products have anti-H. pylori-induced inflammation activity and the relevant mechanisms include suppression of nuclear factor-&#x003ba;B and mitogen-activated protein kinase pathway activation and inhibition of oxidative stress. Anti-H. pylori induced gastric inflammatory effects of plant products, including quercetin, apigenin, carotenoids-rich algae, tea product, garlic extract, apple peel polyphenol, and finger-root extract, have been documented. In conclusion, many medicinal plant products possess anti-H. pylori activity as well as an anti-H. pylori-induced gastric inflammatory effect. Those plant products have showed great potential as pharmaceutical candidates for H. pylori eradication and H. pylori induced related gastric disease prevention.

Role of moxibustion in inflammatory responses during treatment of rat ulcerative colitis

AIM: To investigate the efficacy of moxibustion in ulcerative colitis (UC) rats from morphological, immunological and molecular biological perspectives. METHODS: Thirty-two Sprague-Dawley rats were randomly assigned to a blank control group (normal rats, n = 6) and a model replication (MR) group (UC rats, n = 26). A UC model was established by 2,4,6-trinitrobenzenesulfonic acid/dextran sulfate sodium enema. Rats in the MR group were further randomly assigned to a 9-min moxibustion (9M) group (9 moxa-cone, n = 6), 6-min moxibustion (6M) group (6 moxa-cone, n = 6), 3-min moxibustion (3M) group (3 moxa-cone, n = 6), and a waiting list control (WLC) group (no moxibustion treatment, n = 6). Rats in the moxibustion treatment group were treated in 14 sessions over 28 d. Disease activity, local tissue morphology, serum level of interleukin (IL)-8 and IL-10, and expression of Toll-like receptor (TLR)9 as well as nuclear factor (NF)-kappa B p65 in colonic tissue were determined by disease activity index (DAI), hematoxylin and eosin staining, electron microscopy, enzyme-linked immunosorbent assay and Western blotting, respectively. RESULTS: DAI was lowest in the 9M group and highest in the WLC group. The differences in DAI between the moxibustion treatment (3M, 6M, 9M) and no treatment groups were significant for all one-to-one comparisons (0.60 +/- 0.54 vs 1.20 +/- 0.44, 0.60 +/- 0.54 vs 1.80 +/- 0.45, 0.60 +/- 0.54 vs 3.0 +/- 0.45, respectively, P < 0.05). Light and electron microscopy showed that the neatness of the glandular arrangement in colonic mucosal epithelia gradually increased in the WLC, 3M, 6M to 9M groups. IL-8 level successively decreased while IL-10 level increased from the WLC to 3M, 6M and 9M groups. The differences among these groups were significant for all comparisons (105.46 +/- 8.75 vs 76.61 +/- 3.58, 105.46 +/- 8.75 vs 69.78 +/- 1.87, 105.46 +/- 8.75 vs 67.41 +/- 1.84, respectively, P < 0.01 for IL-8; and 30.83 +/- 1.29 vs 75.64 +/- 1.90, 30.83 +/- 1.29 vs 80.90 +/- 3.16, 30.83 +/- 1.29 vs 83.46 +/- 2.37, respectively, P < 0.01 for IL-10), except comparison of 6M vs 9M. Expression of TLR9 and NF-kappa B p65 decreased in order: highest in the WLC group and lowest in the 9M group. In addition, the differences among the WLC, 3M, 6M and 9M groups were significant for all comparisons (0.492 +/- 0.026 vs 0.380 +/- 0.022, 0.492 +/- 0.026 vs 0.355 +/- 0.005, 0.492 +/- 0.026 vs 0.327 +/- 0.015, respectively, P < 0.05 for TLR9; and 0.436 +/- 0.041 vs 0.326 +/- 0.022, 0.436 +/- 0.041 vs 0.293 +/- 0.006, 0.436 +/- 0.041 vs 0.265 +/- 0.017, respectively, P < 0.05 for NF-kappa B p65). CONCLUSION: Moxibustion repairs damaged colonic mucosa, suppresses serum IL-8, activates serum IL-10 level, and decreases expression of TLR-9 and NF-kappa B p65 in UC rats. (C) 2014 Baishideng Publishing Group Inc. All rights reserved.