Protective effects of pentoxifylline on acute liver injury induced by thioacetamide in rats

Pentoxifylline (PTX) is a non-selective phosphodiesterase inhibitor with the effects of antioxidation, anti-inflammation and anti-fibrosis that has been shown to induce damage in liver. The purpose of this study is to investigate the effects and possible mechanisms of PTX on thioacetamide (TAA)-induced acute liver injury in rats. Male Sprague-Dawley (SD) rats were divided into four groups: control, PTX, TAA and PTX+TAA treated groups. Rats were administrated TAA together with or without PTX for a week and sacrificed 24 h after the last intragastric administration of PTX. Histopathological analysis was carried out. The liver function, the indices of oxidative stress including malondialdehyde (MDA), superoxide dismutase (SOD), and glutathione (GSH) in liver tissues, and pro-inflammatory cytokines expressions were examined. The mRNA level of NF-κB p65 in liver was also determined. PTX significantly attenuated TAA-induced liver injury. The serum transaminase and MDA levels were reduced while the levels of SOD and GSH were increased, as compared with the TAA-treated group. PTX also remarkably suppressed the secretions of pro-inflammatory cytokines and the nuclear factor-κB (NF-κB) activation induced by TAA. In addition, the histopathological analysis showed that the range and degree of liver tissue lesions were improved obviously in PTX treated group. Pentoxifylline could ameliorate the effects of thioacetamide-induced acute liver injury in rats by inhibiting oxidative stress, expressions of pro-inflammatory cytokines and NF-κB activation.     

Anti-inflammatory and antioxidant effects of curcumin on acute lung injury in a rodent model of intestinal ischemia reperfusion by inhibiting the pathway of NF-Kb

Objective: To investigate the anti-inflammatory and antioxidant effect of curcumin on lung lesion induced by intestinal ischemia reperfusion injury (IIR). Methods: Rats were divided into four groups: sham, intestinal IIR (IIR), 1 mg/kg of curcumin treatment group (1 mg/kg), and 5 mg/kg of curcumin treatment group (5 mg/kg). Curcumin was given respectively (1 mg/kg and 5 mg/kg) following the above doses. IIR was produced by 1 h of intestinal ischemia followed by 2 h of reperfusion. Rats were sacrificed at the end of reperfusion and lung tissues were collected for biochemical and histopathological examination in 4 groups. Lung tissues histology and bronchoalveolar lavage fluid (BALF) protein were assayed. Serum IL-6, lung superoxide dismutase (SOD) and myeloperoxidase (MPO) were measured. The expression level of NF-κB and ICAM-1 (including immunohistochemical analysis and western blot analysis) were also measured. Results: Lung tissue injury induced by IIR was obviously observed through pathology and BALF protein. MPO activity, IL-6 level and ICAM-1 expression were significantly increased with the elevation of NF-κB, simultaneously, SOD activity was decreased. With Treatment of curcumin, pathology and BALF protein of lung tissue were improved clearly. Inflammatory indexes (MPO activity, IL-6 level and ICAM-1) were improved and antioxidant index (SOD activity) was enhanced paralleled with NF-κB. Conclusion: Using curcumin effectively prevented IIR-induced lung injury. Anti-inflammatory and antioxidant effects of curcumin could be observed by inhibiting the pathway of NF-κB.     

Unfractionated heparin attenuates intestinal injury in mouse model of sepsis by inhibiting heparanase

Intestinal injury is a key feature in sepsis. Heparanase, a heparin sulfate-specific glucuronidase, mediates the onset of organ injury during early sepsis. Heparin has the function to attenuate inflammation and injury induced by multiple factors; however, whether unfractionated heparin (UFH) can attenuate the intestinal injury induced by sepsis as well as the underlying mechanism is still unknown. In the present study, the function of UFH in intestinal injury induced by sepsis was explored. Results of our study showed that after CLP operation, the inflammatory response and expression of heparanase were increased and NF-κB and MAPK P38 signaling pathways were activated. However, pretreatment with UFH will inhibit the expression and activation of heparanase, and reverse the activation of NF-κB and MAPK P38 signaling pathways, thus attenuating inflammatory responses induced by sepsis. These results suggest that UFH may be a promising therapeutic drug for intestinal injury caused by sepsis.     

Ectopic expressed miR-203 contributes to chronic obstructive pulmonary disease via targeting TAK1 and PIK3CA

MiRNA is a group of powerful short non-coding RNAs that suppress the expression of protein coding genes by targeting to the 3’UTRs of mRNAs. Some researchers have detected the miRNAs expression profile in tissue and blood samples of chronic obstructive pulmonary disease (COPD) patients recently. Several disturbed miRNAs were found to be related to COPD; however, the mechanisms were still well understood. In this study, we first detected the expression of 11 candidate miRNAs in the lung samples of COPD patients, non-COPD smokers and non-smock controls. We found that the expression of miR-181a, miR-203, miR-338, miR-1 and miR-199a was altered compared with control. Subsequently, we detected these five miRNAs expression in the blood samples of the participants. A significant higher expression of miR-203 was found in the blood samples of smokers and COPD patients. Predicted by bioinformatics tools and confirmed by luciferase assay and western blot, we demonstrated that TAK1 and PIK3CA are two direct targets of miR-203. Furthermore, we detected a lower p-IκBα and p-p65 level in the bronchial/tracheal epithelial cells from COPD patients compared with the cells from healthy controls, when stimulated by LPS. The concentration of TNF-α and IL-6 in the medium from bronchial/tracheal epithelial cells from COPD patients is also lower. Meanwhile, the miR-203 level was down-regulated significantly in the control cells, but non-significant change in the cells from COPD patients. miR-203 represses NF-κB signaling via targeting TAK1 and PI3KCA and miR-203 overexpression may contribute to the COPD initiation.     

Effect of mesodiencephalic modulation on small intestinal mucosa after massive blood loss in rats

Effect of mesodiencephalic modulation on small intestinal mucosa was studied in rats subjected to massive blood loss. Massive blood loss induced structural changes in intestinal epitheliocytes typical of tissue hypoxia: intraintestinal edema, mitochondrial alterations, and microcirculation disturbances. A single session of mesodiencephalic stimulation carried out 60 min after massive blood loss produced a pronounced adaptive effect, restored disturbed structure of the intestinal villi, and induced compensatory hypertrophy of the mitochondria. This suggests that mesodiencephalic modulation promotes normalization of intracellular energy metabolism, improves the absorption capacity of bordered enterocytes, and restores the disturbed intestinal barrier.     

Ozone preconditioning and exposure to ketamine attenuates hepatic inflammation in septic rats

Introduction

The objective of this study was to evaluate the interaction between ozone oxidative preconditioning and the anesthetic ketamine on cytoplasmic nuclear factor κB (NF-κB) levels in a rat endotoxic shock model.

Material and methods

Forty Wistar rats were randomly divided into 5 groups: I – control group; II – rats intraperitoneally (i.p.) treated with LPS; III – rats treated with LPS and then treated with ketamine; IV – animals pre-treated with O₃/O₂ mixture for 5 days, then treated with LPS for 24 h followed by infusion with ketamine; V – O₃/O₂ pre-treatment, as described above for IV, followed by LPS infusion, and then 0.9% saline. In addition to histological examination of the liver, the levels of NF-κB were determined by SABC immunohistochemistry in each group.

Results

Histological damage was observed in the lipopolysaccharide (LPS) group. It was characterized by hepatic disarray, hepatic lobule distortion, congestion of liver sinusoids, hepatocyte swelling and necrosis, and granulocyte infiltration. These changes were not obvious in the O₃/O₂ + LPS + ketamine group. The normal control group had low activity of NF-κB, but that activity was markedly increased in the LPS group (p < 0.05). The NF-κB level was significantly decreased in the O₃/O₂ + LPS + ketamine group (p < 0.05) when compared with the ketamine-treated group, and was almost equal to the control group.

Conclusions

We confirmed that the preconditioning effect of ozone enhances the biological effectiveness of ketamine by altering NF-κB activity, which may play an important role in sepsis-induced liver injury in rats.     

Effects of propofol on lipopolysaccharide-induced expression and release of HMGB1 in macrophages

This study aimed to determine the effects of different concentrations of propofol (2,6-diisopropylphenol) on lipopolysaccharide (LPS)-induced expression and release of high-mobility group box 1 protein (HMGB1) in mouse macrophages. Mouse macrophage cell line RAW264.7 cells were randomly divided into 5 treatment groups. Expression levels of HMGB1 mRNA were detected using RT-PCR, and cell culture supernatant HMGB1 protein levels were detected using enzyme-linked immunosorbent assay (ELISA). Translocation of HMGB1 from the nucleus to the cytoplasm in macrophages was observed by Western blotting and activity of nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) in the nucleus was detected using ELISA. HMGB1 mRNA expression levels increased significantly in the cell culture supernatant and in cells after 24 h of stimulating RAW264.7 cells with LPS (500 ng/mL). However, HMGB1 mRNA expression levels in the P2 and P3 groups, which received 500 ng/mL LPS with 25 or 50 μmol/mL propofol, respectively, were significantly lower than those in the group receiving LPS stimulation (P<0.05). After stimulation by LPS, HMGB1 protein levels were reduced significantly in the nucleus but were increased in the cytoplasm (P<0.05). Simultaneously, the activity of NF-κB was enhanced significantly (P<0.05). After propofol intervention, HMGB1 translocation from the nucleus to the cytoplasm and NF-κB activity were inhibited significantly (each P<0.05). Thus, propofol can inhibit the LPS-induced expression and release of HMGB1 by inhibiting HMGB1 translocation and NF-κB activity in RAW264.7 cells, suggesting propofol may be protective in patients with sepsis.     

Synergistic and feedback signaling mechanisms in the regulation of inflammation in respiratory infections

Pneumonia, the most typical and frequent lower respiratory tract infection (LRTI), is a leading cause of health problems in the United States. Bacteria represent the most prevailing cause of pneumonia in both children and adults. Although pneumonia with a single bacterial infection is common, a significant portion of patients with pneumonia is polymicrobial. This infection is often complexed with other physiological factors such as cytokines and growth factors. Nontypeable Haemophilus influenzae (NTHi) is the most frequently recovered Gram-negative bacterial pathogen in the respiratory system and induces strong inflammatory responses. NTHi also synergizes with other respiratory pathogens, such as Streptococcus pneumoniae and respiratory viruses and pro-inflammatory cytokines, such as tumor necrosis factor-alpha (TNF-α). It is noteworthy that NTHi not only synergizes with growth factors such as transforming growth factor-beta (TGF-β), but also utilizes growth factor receptors such as TGF-β receptor and epidermal growth factor receptor (EGFR), to enhance inflammatory responses. Although appropriate inflammation is a protective response against invading pathogens, an uncontrolled inflammatory response is often detrimental to the host. Thus, inflammation must be tightly regulated. The human immune system has evolved strategies for controlling overactive inflammatory response. One such important mechanism is via regulation of negative feedback regulators for inflammation. CYLD, a multifunctional deubiquitinase, was originally reported as a tumor suppressor, but was recently identified as a negative regulator for nuclear factor-kappa B (NF-κB) signaling. It is induced by NTHi and TNF-α via a NF-κB-dependent mechanism, thereby serving as an inducible negative feedback regulator for tightly controlling inflammation in NTHi infection.     

Different doses of partial liver irradiation promotes hepatic regeneration in rat

The aim of this study is to investigate whether partial liver irradiation promotes hepatic regeneration in rat. Left-half liver of rat was irradiated to 10 Gy, and the Right-half to 0, 5, 10 and 15 Gy, respectively. Then, serum alanine aminotransferase (ALT), aspartate aminotransferase (AST) and alkaline phosphatase (ALP) levels were evaluated on 0 day, 15-day, 30-day, 45-day and 60-day after liver irradiation. Next, the serum HGF, NF-κB and TGF-β1 levels were also analyzed on 60-day after liver irradiation. Lastly, the cyclinD1 protein expression was appraised by western blots on 60-day after liver irradiation. ALT, AST and ALP levels were reduced compared with that of controls. The serum HGF, NF-κB and TGF-β1 levels, and the cyclinD1 protein expression in liver irradiation group were increased compared with that of controls group. However, hepatic regeneration of higher dose-irradiated cirrhotic liver was triggered a more enhanced regeneration, compared with that of higher doses group. In summary, these results suggest that different doses of partial liver irradiation promotes hepatic regeneration in rat.     

盐酸戊乙奎醚对粘连性肠梗阻大鼠肠黏膜免疫屏障的保护作用

目的 探讨盐酸戊乙奎醚(PHC)对粘连性肠梗阻(AIO)大鼠肠黏膜免疫屏障功能的影响及可能机制.方法 将60只SD大鼠分为正常组(N组)、假手术组(S组)、生理盐水组(NS组)及盐酸戊乙奎醚组(P2、P4、P8组).建立AIO模型.正常组不予处理,生理盐水组及假手术组均给予0.4 ml生理盐水,PHC组按0.2、0.4、0.8 mg/kg配成0.4 ml,于术后第7d开始连续肌注7d.ELISA法测量血清中IL-4、IL-10含量以及肠内容物中分泌型免疫球蛋白A(sIgA)含量.结果 与S组、NS组比较,P2、P4、P8组血清IL-4[(19.34±2.87),(23.85±2.72),(27.89±2.71) vs (6.18±1.42),(8.37±2.69) ng/L)]、IL-10[(118.93±20.78),(121.61±24.932),(127.41±22.61) vs (78.19±19.41),(42.72±21.31) ng/L]以及肠内容物中sIgA含量(0.64±0.089,0.99±0.093,1.02±0.12 vs 0.41±0.06,0.14±0.03 ng/L)均有明显增高,差异均有统计学意义(均P＜ 0.05).与P2组比较,P4、P8组IL-4与sIgA水平升高更为明显,差异均有统计学意义(P＜ 0.05).结论 中、高剂量PHC对AIO大鼠肠黏膜的免疫屏障有一定保护作用,且以高剂量更为显著,其机制可能与增加抗炎因子释放和抑制炎性因子产生有关.     

Angiotensin Receptor Blockers and Statins Could Alleviate Atrial Fibrosis via Regulating Platelet-Derived Growth Factor/Rac1 /Nuclear Factor-Kappa B Axis

Aims: To investigate whether the administration of renin-angiotensin system (RAS) inhibitors and statins could alleviate atrial fibrosis via platelet-derived growth factor (PDGF)/Rac1 /nuclear factor-kappa B (NF-κB) axis.Methods and Results: In human left atrium, the degree of atrial fibrosis, as well as the expression levels of PDGF, Rac1 and NF-κB increased 1.5 to 2.9 folds in patients with atrial fibrillation compared to that with sinus rhythm, (P<0.0001). There were strongly positive correlations between angiotensin II (Ang II) or procollagen type III-alpha-1 (COL3A1) with PDGF, Rac1, NF-κB, and among PDGF, Rac1 and NF-κB (all P<0.05). At 3 weeks after the transverse aorta constriction (TAC) operation in rat model and with intervention of irbesartan or/and simvastatin, the collagen volume fraction (CVF) and atrial natriuretic peptide (ANP) values respectively increased 6-folds and 3.5-folds in the TAC group compared to SHAM group (P<0.0001), but these levels decreased by 16% to 63% with following drug intervention (all P<0.0001), the combined treatment was the lowest. Accordingly, the expression levels of PDGF (3-folds), Rac1 (1.6-folds), NF-κB (7-folds) and AngII (12-folds) significantly increased in the TAC group compared to the SHAM group, and these levels were also reduced by 25% to 64% with following drug intervention. The highest reduction could be seen after treatment with irbesartan and simvastatin in combination (all P<0.001).There were strongly positive correlations between AngII or CVF with PDGF, Rac1, NF-κB, and among PDGF, Rac1 and NF-κB (all P<0.05).Conclusions: Irbesartan or/and simvastatin can improve atrial fibrosis by regulating PDGF/Rac1/NF-κB axis.     

Inhibitory effect of Paeonia lactiflora Pallas extract (PE) on poly (I:C)-induced immune response of epidermal keratinocytes

Epidermal keratinocytes provide protective role against external stimuli by barrier formation. In addition, kertinocytes exerts their role as the defense cells via activation of innate immunity. Disturbance of keratinocyte functions is related with skin disorders. Psoriasis is a common skin disease related with inflammatory reaction in epidermal cells. We attempted to find therapeutics for psoriasis, and found that Paeonia lactiflora Pallas extract (PE) has an inhibitory potential on poly (I:C)-induced inflammation of keratinocytes. PE significantly inhibited poly (I:C)-induced expression of crucial psoriatic cytokines, such as IL-6, IL-8, CCL20 and TNF-α, via down-regulation of NF-κB signaling pathway in human keratinocytes. In addition, PE significantly inhibited poly (I:C)-induced inflammasome activation, in terms of IL-1β and caspase-1 secretion. Finally, PE markedly inhibited poly (I:C)-increased NLRP3, an important component of inflammasome. These results indicate that PE has an inhibitory effect on poly (I:C)-induced inflammatory reaction of keratinocytes, suggesting that PE can be developed for the treatment of psoriasis.     

Activation of AKT/ERK confers non-small cell lung cancer cells resistance to vinorelbine

Vinorelbine is a semi-synthetic vinca-alkaloid approved for the treatment of non-small cell lung cancer (NSCLC). However, the lower objective response rate and higher adverse effects of vinorelbine hinder its wide use in treatment of advanced NSCLC. Therefore, it is of great interest to uncover the biomarkers for sensitivity of NSCLC cells to vinorelbine to allow the identification of patients most likely to benefit from vinorelbine-based chemotherapy and to improve the therapy. In present work, four NSCLC cell lines were divided into vinorelbine-sensitive (VS) group and vinorelbine-resistant (VR) group according to their sensitivities to vinorelbine. And then the gene expression profiles of these two groups was compared, the differentially expressed genes (expression difference higher than 100% and p<0.05, totally 496 genes) were applied to Ingenuity Pathway Analysis (IPA). IPA results showed that NF-κB and PTEN signaling were predicted to be inactivated in VR cell lines, which was partially validated by quantitative PCR or western blotting experiments. The higher expression of RAF1 mRNA and the activation of AKT/ERK proteins in VR NSCLC cell lines may confer resistance to vinorelbine. Our work may provide potential pathway signature for vinorelbine sensitivity and some therapeutic targets for combined therapy.     

Wortmannin,PI3K/Akt signaling pathway inhibitor,attenuates thyroid injury associated with severe acute pancreatitis in rats

Increasing evidences suggest that PI3K/AKT pathway plays an important role in the pathogenesis of inflammatory diseases such as acute pancreatitis. However, the exact effect of PI3K/AKT on thyroid injury associated with acute pancreatitis has not been investigated. This study aimed to investigate the protective effects of wortmannin, PI3K/AKT inhibitor, on thyroid injury in a rat model of severe acute pancreatitis (SAP). Sixty male SD rats were randomly divided into four groups: sham operating group (SO), SAP group, wortmannin treatment (WOR) group and drug control (WOR-CON) group. Serum amylase (AMY), lipase (LIP) and thyroid hormone levels were evaluated. The morphological change of thyroid tissue was analyzed under the light and transmission electron microscopy. AKT, P38MAPK and NF-κB expression in the thyroid tissue was evaluated by immunohistochemical staining. Oxidative stress and inflammatory cytokines were detected. Results showed that wortmannin attenuated the following: (1) serum AMY, LIP and thyroid hormone (2) pancreatic and thyroid pathological injuries (3) thyroid MDA, (4) thyroid ultrastructural change, (5) serum TNF-α, IL-6 and IL-1β (6) AKT, MAPKP38 and NF-κB expression in thyroid tissues. These results suggested that wortmannin attenuates thyroid injury in SAP rats, presumably because of its role on prevent ROS generation and inhibits the activation of P38MAPK, NF-κB pathway. Our findings provide new therapeutic targets for thyroid injury associated with SAP.     

Intrathecal siRNA against Toll-like receptor 4 reduces nociception in a rat model of neuropathic pain

Background: Neuropathic pain is characterized by hyperalgesia, allodynia and spontaneous pain. It often occurs as a result of injury to peripheral nerves, dorsal root ganglions (DRG), spinal cord, or brain. Recent studies have suggested that Toll-like receptor 4 (TLR4) might play a role in neuropathic pain. Methodology/Principal Findings: In this study, we investigated the role of TLR4 in a rat chronic constriction injury (CCI) model and explored the feasibility of treating neuropathic pain by inhibiting TLR4. Our results demonstrated that intrathecal siRNA-mediated suppression of TLR4 attenuated CCI-induced mechanical allodynia and thermal hyperalgesia through inhibiting the activation of NF-κB p65 and production of proinflammatory cytokines (e.g., TNF-α and IL-1β). Conclusions/Significance: These findings suggest that suppression of TLR4 mediated by intrathecally administered siRNA may be a new strategy for the treatment of neuropathic pain.     

Delayed preconditioning effect of isoflurane on spinal cord ischemia in rats

Paraplegia is one of the most common complications following aortic aneurysmal surgery. This study was designed to determine if isoflurane-induced delayed preconditioning is mediated by nuclear factor kappaB (NF-kappaB) in the rat spinal cord. The animals were divided into four groups: the control group, the pyrrolidinedithio carbamate (PDTC, an NF-kappaB inhibitor)-treated group, the isoflurane-treated group, and the PDTC/isoflurane-treated group. In the PDTC-treated groups, 2% 100mg/kg PDTC was administered intraperitoneally at 1h before operation and at 24h and 48 h after reperfusion. The rats in the isoflurane-treated groups received 30 min inhalation of 2.8% isoflurane at 24h before spinal cord ischemia. Pretreatment with NF-kappaB inhibitor significantly reduced NF-kappaB expression and the number of intact motor neurons when compared to the control group. Preconditioning with isoflurane increased the number of normal motor neurons, whereas pretreatment with both PDTC and isoflurane significantly decreased them, compared to the isoflurane-treated group. Isoflurane-induced delayed preconditioning on spinal cord ischemia improved histopathological outcomes. This neuroprotective effect of isoflurane preconditioning on spinal cord ischemia is associated with NF-kappaB expression.