Gene delivery of TIPE2 attenuates collagen-induced arthritis by modulating inflammation

Rheumatoid arthritis (RA) is an autoimmune disease that leads to severe disabilities through the induction of synovitis and subsequent cartilage and bone destruction. The development of a novel therapeutic strategy for suppressing inflammatory responses in RA will be of great benefit to patients. Tumor necrosis factor-alpha-induced protein 8-like 2 (TIPE2) is an important regulator of immune response in various diseases. However, the expression and function of TIPE2 in RA are still unclear. In the present study, the expression of TIPE2 during the development of collagen-induced arthritis (CIA) was determined. Lentivirus (LV) was utilized to deliver a TIPE2 overexpression system into the joints of CIA mice, and this was followed by pathological analysis, immune cell infiltration analysis, and inflammatory cytokine detection. TIPE2 was downregulated in CIA mice, which was inversely correlated with arthritis progression. The ectopic expression of TIPE2 from gene delivery prevented susceptibility and disease severity by inhibiting the infiltration of macrophages and myeloid-derived suppressor cells (MDSCs) in the joints of CIA mice. Furthermore, lower expression of proinflammatory cytokines was observed in LV-TIPE2-injected CIA mice, which was in part associated with the activation of STAT3 and NF-κB signaling pathways in the cartilage cells. These data support the suppressive function of TIPE2 in autoimmune diseases and identify the gene delivery of TIPE2 as an important therapeutic agent for the treatment of RA and perhaps other autoimmune diseases.     

Protective effects of thymoquinone and methotrexate on the renal injury in collagen-induced arthritis

The goal of this investigation was to study the protective effects of thymoquinone (TQ) and methotrexate (MTX) on collagen-induced arthritis (CIA) in rats. On day 0 under ether anesthesia, the experimental groups were immunized with 0.5 mg native chick collagen II (CII) solubilized in 0.1 M acetic acid and emulsified in Freund's incomplete adjuvant. Control rats were gavaged with vehicle, whereas CII was administered intradermally. In addition, arthritis treated with TQ group received TQ (10 mg kg(-1) bw by gavage once a week for 3 weeks starting on day 0); and arthritis treated with MTX group received MTX (MTX was suspended in corn oil and administered by gavage at 1 mg kg (-1) bw once a week for 3 weeks starting on day 0). A significant decrease in the incidence and severity of arthritis by clinical and radiographic assessments was found in recipients of therapy, compared with that of controls. The MTX treatment significantly (P<0.01) decreased the elevated serum NO, urea and creatinine in arthritic rats. Likewise, TQ treatment was also able to reduce significantly (P<0.05) serum NO, urea and creatinine levels, but to lesser extent than MTX. The histopathologic abnormalities are consistent with the hydropic epithelial cell degenerations and moderate tubular dilatation in the some proximal and distal tubules. The severity of the degenerative changes in most of the shrunken glomerules and vascular congestion were also observed in arthritic animals. Preventive treatment of TQ and especially MTX significantly inhibited kidney dysfunction and this histopathologic alterations. These studies indicate that TQ can be used similar to MTX as a safe and effective therapy for CIA and may be useful in the treatment of rheumatoid arthritis.     

N-acetylcysteine attenuates dimethylnitrosamine induced oxidative stress in rats

Oxidative stress has been implicated in the pathogenesis and progression of various hepatic disorders and hence screening for a good hepatoprotective and antioxidant agent is the need of the hour. The present study was aimed to investigate the hepatoprotective and antioxidant property of N-acetylcysteine (NAC) against dimethylnitrosamine (DMN) induced oxidative stress and hepatocellular damage in male Wistar albino rats. Administration of single dose of DMN (5 mg/kg b.w.; i.p.) resulted in significant elevation in the levels of serum aspartate transaminase and alanine transaminase, indicating hepatocellular damage. Oxidative stress induced by DMN treatment was confirmed by an elevation in the status of lipid peroxidation (LPO) and reduction in the activities of enzymic antioxidants such as superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase and glutathione-S-transferase and in the levels of non-enzymic antioxidants, reduced glutathione, vitamin-C and vitamin-E in the liver tissue. DMN induced oxidative stress and hepatocellular membrane instability was further substantiated by a decline in the status of the membrane bound ATPases in the liver tissue. Post-treatment with NAC (50 mg/kg b.w.; p.o.) for 7 days effectively protected against the DMN induced insult to liver by preventing the elevation in the status of the serum marker enzymes and LPO, and restoring the activities of both the enzymic and non-enzymic antioxidants and membrane bound ATPases towards normalcy. These results demonstrate that NAC acts as a good hepatoprotective and antioxidant agent in attenuating DMN induced oxidative stress and hepatocellular damage.     

Crocin ameliorates methotrexate-induced liver injury via inhibition of oxidative stress and inflammation in rats

BackgroundMethotrexate (MTX) is used commonly in the treatment of various cancers and inflammatory diseases; nevertheless, the associated hepatotoxicity has limited its clinical application. Crocin (CRO) is described as a natural carotenoid with analgesic, antioxidant, and antiinflammatory properties. This study aimed to determine the effects of CRO on MTX-induced hepatotoxicity.MethodsFor pretreatment, CRO at doses of 25 and 50 mg/kg (po), as well as 20 mg/kg (ip) of MTX, was injected in rats.ResultsMTX led to hepatotoxicity, as confirmed by the significant increase in liver markers, histopathological changes, decreased GSH content, and reduced antioxidant enzyme activity (i.e., CAT, SOD, and GPx). It increased TNF-α, IL-1β, lipid peroxidation, and nitric oxide levels. Nevertheless, by increasing antioxidant defense in hepatic tissues and reducing oxidative stress and proinflammatory mediators, pretreatment with CRO could alleviate hepatotoxicity.ConclusionCRO can inhibit MTX-induced hepatotoxicity through improving antioxidant defense and reducing oxidative stress and inflammation.     

Crocin attenuates hemorrhagic shock-induced oxidative stress and organ injuries in rats

We aimed to evaluate the effect of natural antioxidant crocin in alleviating hemorrhagic shock (HS)-induced organ damages. HS rats were treated with crocin during resuscitation. Mortality at 12 h and 24 h post resuscitation was documented. HS and resuscitation induced organ injuries, as characterized by elevated wet/dry ratio, quantitative assessment ratio, blood urea nitrogen, creatinine, aspartate aminotransferase and alanine aminotransferase, whereas rats received crocin treatment demonstrated improvements in all the above characteristics. This protective effect coincided with reduced malondialdehyde and increased glutathione in both serum and lung tissues, indicating attenuated oxidative stress in crocin-treated rats. Myeloperoxide levels in lung, kidney and liver were also reduced. Crocin can potentially be used to protect organs from HS-induced damages during resuscitation due to its anti-oxidative role.     

Involvement of oxidative stress in hepatocellular tumor-promoting activity of oxfendazole in rats

The tumor-promoting effects of oxfendazole (OX), a benzimidazole anthelmintic, were investigated using a medium-term rat hepatocarcinogenesis model. Six-week-old male F344 rats received an intraperitoneal injection of N-diethylnitrosamine (DEN) and were given a powdered diet containing 0 or 500 ppm OX for 6 weeks from 2 weeks after DEN treatment. All animals were subjected to two-thirds partial hepatectomy 1 week after OX treatment. The numbers and areas of glutathione S-transferase placental form (GST-P)-positive foci were significantly increased in the livers of rats treated with OX, with concomitantly increased cell proliferation, compared with those in the livers of the DEN alone group. Quantitative real-time RT-PCR analysis revealed that OX induced not only mRNA expression of phase I enzymes Cyp1a1, Cyp1a2, but also Nrf2-regulated phase II enzymes such as Gpx2, Nqo1, Yc2, Akr7a3 and Gstm1, presumably due to an adaptive response against OX-induced oxidative stress. Reactive oxygen species production increased in microsomes isolated from the livers of OX-treated rats. Furthermore, OX enhanced oxidative DNA damage (as assessed by 8-hydroxydeoxyguanosine; 8-OHdG) and lipid peroxidation (as assessed by thiobarbituric acid-reactive substances; TBARS). These results suggest that administration of OX at a high dose and for a long term enhances oxidative stress responses, which may contribute to its tumor-promoting potential in rats.     

染料木素对野百合碱诱导的大鼠肺动脉高血压的保护作用

目的 研究染料木素对野百合碱引起的肺动脉高血压（PH）模型大鼠的降压作用及机制。方法 大鼠随机分组后,模型组及染料木素组大鼠sc 50 mg/kg野百合碱制备PH模型,对照组sc生理盐水。野百合碱注射后第3天,染料木素低、中、高剂量组ig染料木素10、50、100 mg/kg,对照组和模型组大鼠ig给予等体积生理盐水,1次/d,连续2周。末次给药后,采用尾套法测量清醒大鼠尾部动脉血压;小动物生理仪检测大鼠平均心室压和收缩压;荧光实时定量PCR（RT-qPCR）检测血清白细胞介素（IL）-6、IL-8、IL-1β、肿瘤坏死因子-α（TNF-α）、转化生长因子-β（TGF-β）水平;试剂盒测定大鼠血清超氧化物歧化酶（SOD）值及丙二醛（MDA）、总抗氧化能力（T-AOC）和活性氧（ROS）水平。结果 与模型组比较,染料木素50、100 mg/kg组动脉血压、右心室收缩压（RVSP）和右心室舒张末期压（RVeDP）均显著下降（P<0.05、0.01）;染料木素10、50、100 mg/kg剂量均可显著降低大鼠血清中IL-6、IL-8、IL-1β、TNF-α、TGF-β的表达（P<0.05、0.01）;染料木素10、50、100 mg/kg剂量组ROS和MDA水平显著降低,而T-AOC和SOD水平显著增加（P<0.05、0.01）。结论 染料木素对野百合碱诱导的PH大鼠具有降低血压的作用,其机制可能与其阻断氧化应激有关。     

Yohimbine hydrochloride ameliorates collagen type‐II‐induced arthritis targeting oxidative stress and inflammatory cytokines in Wistar rats

Rheumatoid arthritis (RA) is the most common type of chronic inflammatory disease which is triggered by dysfunction in the immune system which in turn affects synovial joints. Current treatment of RA with NSAIDs and DMRDs is limited by their side effect. As a result, the interest in alternative, well tolerated anti‐inflammatory remedies has re‐emerged. Our aim was to evaluate the antioxidant and anti‐inflammatory activities underlying the anti‐RA effect of Yohimbine hydrochloride (YCL) in collagen induced arthritis (CIA) in Wistar rats. The YCL was administered at doses of 5 and 10 mg kg^?1 body weight once daily for 28 days. The effects of treatment in the rats were assessed by biochemical parameter (articular elastase, LPO, GSH, catalase, SOD), hematological parameter (ESR, WBC, C‐reactive protein (CRP), immunohistochemical expression (COX2, TNF‐α, and NF‐κB), and histological changes in joints. YCL showed anti‐RA efficacy as it significantly reduced articular elastase, LPO and catalase level and ameliorates histological changes. This is in addition to its antioxidant efficacy as YCL shown a significant increase in GSH and SOD level. Also, YCL showed effective anti‐inflammatory activity as it significantly decreased the expression of COX‐2, TNF‐α, and NF‐?B. The therapeutic effect of YCL against RA was also evident from lower arthritis scoring and reduced hematological parameter (ESR, WBC, and C‐reactive protein level). The abilities to inhibit proinflammatory cytokines and modulation of antioxidant states that the protective effect of YCL on arthritis rats might be mediated via the modulation of the immune system. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 619–629, 2017.     

Metallothionein attenuates carmustine-induced oxidative stress and protects against pulmonary fibrosis in rats

The present study was carried out to evaluate the effect of exogenously administered metallothionein (MT) against carmustine (BCNU)-induced lung toxicity in rats. A total of 60 rats were randomly divided into four groups (15/group): control group in which the animals received 0.5 ml physiologic saline containing 10% ethanol (IP) weekly, MT-administered group in which rats received MT (30 μmol/kg, IP) weekly, BCNU-administered group in which rats received BCNU (5 mg/kg, IP) weekly and MT + BCNU group in which rats received weekly doses of BCNU (5 mg/kg, IP) followed 24 h later by MT (30 μmol/kg, IP). At the end of the experiment (after 6 weeks), lung histological changes, collagen staining, the activity of glutathione reductase (GR) and contents of reduced glutathione (GSH) and hydroxyproline (Hpr) in the lung as well as serum level of tumor necrosis factor-alpha (TNF-α) were evaluated. The obtained data revealed that BCNU induced pathological changes and markedly increased lung collagen and level of Hpr but decreased GSH content and GR activity and increased serum TNF-α compared to both control and MT-administered rats. Administration of MT + BCNU markedly improved histological features and decreased staining of collagen along with increased GR activity, GSH content but decreased level of Hpr in lung tissue as well as decreased serum level of TNF-α compared with BCNU-treated rats. Based on our results, it is possible to postulate that exogenous MT can act against BCNU-induced lung toxicity by a mechanism related, at least in part, to its ability to decrease oxidative stress and fibrosis.     

Toxic effects of zearalenone on oxidative stress,inflammatory cytokines,biochemical and pathological changes induced by this toxin in the kidney of pregnant rats

An experiment was conducted to determine the toxic effects of zearalenone (ZEN) on oxidative stress, inflammatory cytokines, biochemical and pathological changes in the kidney of pregnant rats, and to explore the possible mechanism in ZEN induced kidney damage. The rats were fed a normal diet treated with 0.3, 48.5, 97.6 or 146 mg/kg ZEN in feed on gestation days (GDs) 0 through 7, and then all the rats were fed with a normal diet on GDs 8 through 20. The results showed that ZEN induced kidney dysfunction, oxidative damage, pathological changes and increased mRNA and protein expression of TLR4 and inflammatory cytokines in kidney in dose-dependent manner. The results indicated that ZEN caused kidney damage of pregnant rats and TLR4-mediated inflammatory reactions signal pathway was one of the mechanisms of ZEN mediated toxicity in kidney.     

热休克蛋白70肽段抑制胶原诱导关节炎小鼠Th17细胞生成

目的:研究HSP70肽段对CIA小鼠Th17细胞的影响,探讨其抑制CIA小鼠炎症损伤的机制。方法:将DBA/1小鼠随机分为HSP70肽段实验组、阴性对照组、结核菌素(PPD)对照组、阳性对照组。除阴性对照组外,其它各组小鼠用牛Ⅱ型胶原蛋白诱导关节炎。通过关节评分和病理改变评价病变程度。取外周淋巴结用流式细胞仪检测Th17细胞的数量,用实时定量PCR检测Th17细胞相关调控因子。结果:注射HSP70肽段的CIA小鼠其Th17细胞数量明显低于阳性对照组和PPD对照组,促进Th17细胞分化发育的相关因子IL-6、IL-23、TGF-β1、RORγt的表达水平低于阳性对照组和PPD对照组(P<0.05)。结论:HSP70肽段可调节Th17细胞分化的调控因子,抑制Th17细胞的分化,进而减轻CIA小鼠的炎症程度。     

Crocin attenuates cisplatin-induced renal oxidative stress in rats

Reactive oxygen species (ROS) and oxidative damage are the most important factors in cisplatin-induced acute renal failure. This study examined the protective effects of crocin against cisplatin-induced renal oxidative stress in rat. Animals were divided into five groups (n = 6). Group 1 received normal saline (2 ml/day, i.p.). Group 2 received a single dose of cisplatin (5 mg/kg, i.p.). Groups 3–5 received crocin (100, 200, and 400 mg/kg, i.p., respectively) for four consecutive days beginning 1-h before a single dose of cisplatin (5 mg/kg) on day 1. On day 5, blood samples were drawn and kidneys were removed for histopathological, biochemical and RT-PCR examinations. Twenty four hours urinary chemistries were measured. Blood urea and creatinine and urinary glucose and protein concentrations in crocin-treated groups were significantly lower compared to the cisplatin-treated group. Histopathological studies showed massive damage in the S₃ segment of proximal tubules in cisplatin-treated group but not in crocin-treated groups. Crocin treatment resulted in a significant reduction in malondialdehyde (MDA) concentration and produced a significant elevation in total thiol and glutathione peroxidase concentrations. There was a significant elevation in the mRNA expression of glutathione peroxidase in crocin-treated groups. The results suggest that crocin attenuates cisplatin-induced renal oxidative stress in rats.     

大鼠胶原诱导性关节炎模型的制备及评价

目的:制备型胶原诱导性关节炎大鼠模型(CIA模型)。方法:将40只大鼠随机分为正常组和模型组。以酶联免疫吸附测定法(ELISA法)检测模型组和正常组大鼠血清中炎性细胞因子肿瘤坏死因子-α(TNF-α)水平,同时采用组织病理学和X线摄片的方法显示关节炎大鼠的发病程度和病理学特征。结果:与正常组相比,模型组在免疫后第36天关节肿胀达到最高峰。ELISA法检测结果显示模型组TNF-α的水平均较正常组大鼠明显增高(P<0.05)。组织病理学和X射线摄片结果显示,关节软骨组织、骨组织和滑膜组织呈典型的关节炎病变。结论:胶原诱导的大鼠关节炎模型,其病理特征和人类类风湿关节炎(RA)极为相似,为进一步深入研究人类RA的发病机制及其临床治疗提供了有价值的实验材料。     

Transient oxidative stress and inflammation after intraperitoneal administration of multiwalled carbon nanotubes functionalized with single strand DNA in rats

Multi-walled carbon nanotubes (MWCNTs) are widely used for nanotechnology. Their impact on living organisms is, however, not entirely clarified. Oxidative stress and inflammation seem to be the key mechanisms involved in MWCNTs' cytotoxicity. Until present, pulmonary and skin models were the main tested experimental designs to assess carbon nanotubes' toxicity. The systemic administration of MWCNTs is essential, with respect for future medical applications. Our research is performed on Wistar rats and is focused on the dynamics of oxidative stress parameters in blood and liver and pro-inflammatory cytokines in liver, after single dose (270 mg l^− 1) ip administration of MWCNTs (exterior diameter 15-25 nm, interior diameter 10-15 nm, surface 88 m² g^− 1) functionalized with single strand DNA (ss-DNA). The presence of MWCNTs in blood was assessed by Raman spectroscopy, while in liver histological examination and confocal microscopy were used. It was found that ss-DNA-MWCNTs induce oxidative stress in plasma and liver, with the return of the tested parameters to normal values, 6 h after ip injection of nanotubes, with the exception of reduced glutathione in plasma. The inflammatory cytokines (TNF-α, IL-1β) had a similar pattern of evolution. We also assessed the level of ERK1/2 and the phosphorylation of p65 subunit of NF-kB in liver that had a transient increase and returned to normal at the end of the tested period. Our results demonstrate that ss-DNA-MWCNTs produce oxidative stress and inflammation, but with a transient pattern. Given the fact that antioxidants modify the profile not only for oxidative stress, but also of inflammation, the dynamics of these alterations may be of practical importance for future protective strategies.     

Therapeutic effects of TACI-Ig on collagen-induced arthritis by regulating T and B lymphocytes function in DBA/1 mice

To investigate the abnormal function of T and B lymphocytes involved in collagen-induced arthritis in DBA/1 mice and the regulation role of TACI-Ig on T and B lymphocytes, collagen-induced arthritis models were established in DBA/1 mice. Mice were divided randomly into eight groups, including normal, collagen-induced arthritis model, TACI-Ig (0.350, 1.105, 3.333, 10, and 30 mg/kg) and IgG-Fc (10 mg/kg) treated groups. The effect of TACI-Ig on collagen-induced arthritis was evaluated by arthritis scores, joints and spleens histopathology, paws radiology, and indices of thymus and spleen. T and B lymphocyte proliferations were assayed by [³H]-TdR method. B lymphocyte stimulator and prostaglandin E₂ in serum were assayed by enzyme linked immunosorbent assay. The subsets of T and B lymphocytes were assayed by flow cytometry. Results showed that the onset of paw-swelling was on day 31 after immunization. The peak of inflammation appeared on day 42 and then declined after day 63. Compared with normal mice, collagen-induced arthritis mice have increased arthritis scores, spleen and thymus indices, radiograph scores of joints, and pathology scores of joints and spleens. TACI-Ig could ameliorate these changes and reduce the increased serum level of B lymphocyte stimulator and prostaglandin E₂. Further studies showed that TACI-Ig inhibited T and B lymphocyte proliferation response, and inhibited differentiation and activity of T and B lymphocytes in collagen-induced arthritis mice. In conclusion, TACI-Ig has a good therapeutic action on collagen-induced arthritis mice, which might be related to the regulation of TACI-Ig on inflammation mediators and abnormal function of T and B lymphocytes.     

Tangeretin ameliorates oxidative stress in the renal tissues of rats with experimental breast cancer induced by 7,12-dimethylbenz[a]anthracene

Tangeretin, a citrus polymethoxyflavone, is an antioxidant modulator which has been shown to exhibit a surfeit of pharmacological properties. The present study was hypothesized to explore the therapeutic activity of tangeretin against 7,12-dimethylbenz[a]anthracene (DMBA) induced kidney injury in mammary tumor bearing rats. Recently, we have reported the chemotherapeutic effect of tangeretin in the breast tissue of DMBA induced rats. Breast cancer was induced by “air pouch technique” with a single dose of 25 mg/kg of DMBA. Tangeretin (50 mg/kg/day) was administered orally for four weeks. The renoprotective nature of tangeretin was assessed by analyzing the markers of oxidative stress, proinflammatory cytokines and antioxidant competence in DMBA induced rats. Tangeretin treatment revealed a significant decline in the levels of lipid peroxides, inflammatory cytokines and markers of DNA damage, and a significant improvement in the levels of enzymatic and non-enzymatic antioxidants in the kidney tissue. Similarly, mRNA, protein and immunohistochemical analysis substantiated that tangeretin treatment notably normalizes the renal expression of Nrf2/Keap1, its downstream regulatory proteins and the inflammatory cytokines in the DMBA induced rats. Histological and ultrastructural observations also evidenced that the treatment with tangeretin effectively protects the kidney from DMBA-mediated oxidative damage, hence, proving its nephroprotective nature.     

Amelioration of collagen-induced arthritis by Salix nigra bark extract via suppression of pro-inflammatory cytokines and oxidative stress

Our study goals to investigate the anti-arthritic potential of Salix nigra bark methanol extract (SNME) against both inflammation and oxidative stress in the collagen-induced arthritis (CIA) rat model. Results showed that SNME exhibited maximum scavenging activity against superoxide, hypochlorous acid and hydrogen peroxide radicals along with the suppression of lipid peroxidation. Female wistar rats were immunized with porcine type II collagen and treated with SNME (100 mg/kg body weight) for 15 days starting on day 20. SNME significantly inhibited the paw swelling and arthritic score; exhibited maximum CIA inhibition of 93.7% by the end of the experimental period. Administration of SNME to arthritic rats significantly improved the histological findings in joints as evident by reduced infiltration of polymorphonuclear cells and smooth synovial lining. Roentgenograms of tibiotarsal joints of both SNME and indomethacin-treated rats showed protection against osteophyte formation, soft tissue swelling and bone resorption. Furthermore, levels of inflammatory mediators (nitric oxide, TNF-α, IL-1β, IL-6) measured in both plasma and joint exudates were significantly reduced by SNME treatment. Increased oxidative stress observed in the arthritic animals was also found to be significantly restored in SNME- treated rats. Taken together, our studies clearly indicate the potential of S. nigra as an anti-arthritic agent.     

Hesperetin attenuated acetaminophen-induced hepatotoxicity by inhibiting hepatocyte necrosis and apoptosis,oxidative stress and inflammatory response via upregulation of heme oxygenase-1 expression

Acetaminophen (APAP) is a common antipyretic and analgesic drug, but its overdose can induce acute liver failure with lack of effective therapies. Hesperetin, a dihydrogen flavonoid compound, has been revealed to exert multiple pharmacological activities. Here, we explored the protective effects and mechanism of hesperetin on APAP-induced hepatotoxicity. The results showed that pretreatment with hesperetin dose-dependently attenuated APAP-induced acute liver injury in mice, as measured by alleviated serum enzymes activities, hepatic pathological damage and apoptosis. Moreover, hesperetin mitigated APAP-induced oxidative stress and inflammatory response in mice by inhibiting oxidative molecules but increasing antioxidative molecules production, reducing inflammatory cells infiltration and proinflammatory cytokines production, blocking Toll-like receptor (TLR)-4 signal activation. In vitro experiment indicated that hesperetin dose-dependently inhibited APAP-primed cytotoxicity, apoptosis, and reactive oxygen species (ROS) in murine AML12 hepatocytes. Notably, hesperetin up-regulated expression of heme oxygenase-1 (HO-1) mRNA and protein in the liver of mice and AML12 cells exposed to APAP. Furthermore, knockdown of HO-1 by adenovirus-mediated HO-1 siRNA reverted these beneficial effects of hesperetin on APAP-induced hepatocytotoxicity as well as ROS and inflammatory response in vivo and in vitro. These findings demonstrated that hesperetin exerted a protective prophylaxis on APAP-induced acute liver injury by inhibiting hepatocyte necrosis and apoptosis, oxidative stress and inflammatory response via up-regulating HO-1 expression.     

Curcumin attenuates indomethacin-induced oxidative stress and mitochondrial dysfunction

Oxidative stress and mitochondrial dysfunction have been implicated in the pathogenesis of indomethacin-induced enteropathy. We evaluated the potential of curcumin, a known cytoprotectant, as an agent to protect against such effects. Rats were pretreated with curcumin (40 mg/kg by intra-peritoneal injection) before administration of indomethacin (20 mg/kg by gavage). One hour later, the small intestine was isolated and used for assessment of parameters of oxidative stress. Mitochondria, brush border membranes (BBM) and surfactant-like particles (SLP) were also isolated from the tissue. Mitochondria were used for assessment of functional integrity, estimation of products of lipid peroxidation and lipid content. BBM were used for estimation of products of lipid peroxidation and lipid content, while the SLP were used for measurement of lipid content. The results showed that oxidative stress and mitochondrial dysfunction occurred in the small intestine of indomethacin-treated rats. Pre-treatment with curcumin was found to ameliorate these drug-induced changes. Significant changes were seen in some of the lipids in the mitochondria, BBM and SLP in response to indomethacin. However, curcumin did not have any significant effect on these drug-induced changes. We conclude that curcumin, by attenuating oxidative stress and mitochondrial dysfunction, holds promise as an agent that can potentially reduce NSAID-induced adverse effects in the small intestine.