Hirudin improves renal interstitial fibrosis by reducing renal tubule injury and inflammation in unilateral ureteral obstruction (UUO) mice

Renal interstitial fibrosis (RIF) often occurs in many chronic kidney diseases (CKD). Hirudin now is applied to treat fibrosis in some organs. In this study, we verified the treatment effects of hirudin on RIF in vivo and in vitro with the underlying mechanism. The RIF in vivo was the unilateral ureteral obstruction (UUO) model and RIF in vitro was the renal tubular epithelial cells induced by TGF-β. The renal pathological changes and renal fibrosis were observed by hematoxylin and eosin (H&E) staining and Masson staining. The α-SMA in renal tissues was detected by immunohistochemistry. The inflammatory factors were analyzed by the ELISA assay. The cell apoptosis was observed by TUNEL assay. The related proteins of fibrosis, epithelial-mesenchymal transition (EMT) and apoptosis were assessed by western blot analysis. The experimental data demonstrated that hirudin decreased fibrosis, EMT, inflammation and cell apoptosis in renal tissues of UUO rats and TGF-β-induced renal tubular epithelial cells. Furthermore, hirudin also reduced the expression of collgen-I, FN, α-SMA, N-cad, slug, E-cad, IL-1β, IL-6 and TNF-α in mice serum and TGF-β-induced renal tubular epithelial cells. The apoptosis related proteins (pro-caspase3, pro-caspase9, bcl2 and bax) expression was also down-regulated in renal tissues of UUO rats. In conclusion, hirudin depressed the fibrosis in renal tissues and renal tubular epithelial cells by inhibiting the inflammation, regulating the related proteins of fibrosis and ETM and decreasing the apoptosis of renal tubular epithelial cells. These findings may offer an effective treatment method for RIF.     

Splenectomy enhances the Ly6Clow phenotype in hepatic macrophages by activating the ERK1/2 pathway during liver fibrosis

Background and aim: Splenectomy has been reported to attenuate liver fibrosis. In addition, phenotype transitions of infiltrating macrophages, including Ly6C^high and Ly6C^low, play an essential role in the liver fibrosis. However, whether the spleen can regulate the phenotype switch of macrophages and the underlying mechanism still remain unclear. Methods: Chronic liver fibrosis in mice was induced by intraperitoneal injection with carbon tetrachloride. Splenectomy or sham operation was performed with or without depletion of macrophages during liver fibrosis. Liver fibrosis and the proportion of Ly6C^high and Ly6C^low macrophages were analyzed. Western blotting of ERK1/2 signals was performed in isolated macrophages to investigate the underlying mechanism of phenotype transition. RAW264.7 cells were stimulated by liver total cells conditioned medium with or without preincubation of SCH772984, the ERK1/2 inhibitor, and the phenotype switch of RAW264.7 cells was examined. In vivo, intraperitoneal injection of SCH772984 was performed on the splenectomy mice and the phenotype switch of liver infiltrating macrophages was tested. Results: Splenectomy alleviated the liver inflammation and fibrosis and also promoted the phenotypic switch of infiltrating macrophages to a Ly6C^low phenotype in fibrotic liver. The p-ERK1/2 expression was upregulated in macrophages at the same time. Furthermore, splenectomy increased the percentage of Ly6C^low macrophages and decreased the percentage of Ly6C^high macrophages both in vivo and in vitro, which was reversed by SCH772984. Conclusions: Splenectomy attenuates both the liver fibrosis and inflammation, and promotes the phenotype switch of infiltrating macrophages to an anti-inflammatory Ly6C^low phenotype by activating the ERK1/2 pathway during liver fibrosis.     

Epigallocatechin-3-gallate attenuates cadmium-induced chronic renal injury and fibrosis

Cadmium (Cd) pollution is a serious environmental problem. Kidney is a main target organ of Cd toxicity. This study was undertaken to investigate the potential protective effects of epigallocatechin-3-gallate (EGCG) against chronic renal injury and fibrosis induced by CdCl₂. Rat model was induced by exposing to 250 mg/L CdCl₂ through drinking water. The renal function was evaluated by detecting the levels of blood urea nitrogen (BUN) and serum creatinine (SCR). The oxidative stress was measured by detecting the levels of malondialdehyde (MDA), nitric oxide (NO), reduced glutathione/oxidized glutathione (GSH/GSSG) and renal enzymatic antioxidant status. Additionally, the renal levels of transforming growth factor-β1 (TGF-β1), Smad3, phosphorylation-Smad3 (pp-Smad3), α-smooth muscle actin (α-SMA), vimentin and E-cadherin were measured by western blot assay. Renal levels of microRNA-21 (miR-21), miR-29a/b/c and miR-192 were measured by quantitative RT-PCR. It was found that EGCG ameliorated the CdCl₂-induced renal injury, inhibited the level of oxidative stress, normalized renal enzymatic antioxidant status and E-cadherin level, as well as attenuated the over generation of TGF-β1, pp-Smad3, vimentin and α-SMA. EGCG also decreased the production of miR-21 and miR-192, and enhanced the levels of miR-29a/b/c. These results showed that EGCG could attenuate Cd induced chronic renal injury.     

Emodin attenuates severe acute pancreatitis-associated acute lung injury by suppressing pancreatic exosome-mediated alveolar macrophage activation

Severe acute pancreatitis-associated acute lung injury (SAP-ALI) is a serious disease associated with high mortality. Emodin has been applied to alleviate SAP-ALI; however, the mechanism remains unclear. We report that the therapeutic role of emodin in attenuating SAP-ALI is partly dependent on an exosomal mechanism. SAP rats had increased levels of plasma exosomes with altered protein contents compared to the sham rats. These infused plasma exosomes tended to accumulate in the lungs and promoted the hyper-activation of alveolar macrophages and inflammatory damage. Conversely, emodin treatment decreased the plasma/pancreatic exosome levels in the SAP rats. Emodin-primed exosomes showed less pro-inflammatory effects in alveolar macrophages and lung tissues than SAP exosomes. In detail, emodin-primed exosomes suppressed the NF-κB pathway to reduce the activation of alveolar macrophage and ameliorate lung inflammation by regulating PPARγ pathway, while these effects were amplified/abolished by PPARγ agonist/antagonist. Blockage of pancreatic acinar cell exosome biogenesis also exhibited suppression of alveolar macrophage activation and reduction of lung inflammation. This study suggests a vital role of exosomes in participating inflammation-associated organ-injury, and indicates emodin can attenuate SAP-ALI by reducing the pancreatic exosome-mediated alveolar macrophage activation.     

乌司他丁对脓毒症致急性肾损伤大鼠肾脏病理及尿相关指标的影响

目的探讨乌司他丁对盲肠结扎穿孔术（CLP）所致大鼠脓毒症急性肾损伤肾脏病理及尿相关指标的影响。方法 SD健康雄性大鼠55只,按随机化原则分成3组：正常对照组5只、模型组25只、乌司他丁治疗组25只,后两组再随机分为5个时间点（1、6、12、24、48 h）,每组每时间点各5只,采用CLP复制脓毒症模型,乌司他丁治疗组造模后立即给予乌司他丁100 000 U/kg,尾静脉注射,分别在各个时间点采血、留尿标本,处死大鼠摘取肾脏,进行肾功能血肌酐（SCr）、尿素氮（BUN）,尿肾损伤分子（KIM-1）、白细胞介素-18（IL-18）和中性粒细胞明胶酶相关脂质运载蛋白（NGAL）检测分析,光镜下观察肾脏病理变化。结果模型组SCr、BUN的浓度CLP术后6 h开始升高,24 h达高峰,48 h开始下降,均显著高于对照组（P〈0.05）,乌司他丁治疗组12、24、48 h均显著低于相应时间点模型组（P〈0.05）。模型组尿KIM-1、NGAL、IL-18含量于CLP术后1 h开始升高,12 h达高峰,24 h开始下降,均显著高于对照组,乌司他丁治疗组6、12、24、48 h均显著低于相应时间点模型组（P〈0.05）。肾脏病理改变明显好于模型组。结论乌司他丁对脓毒症所致急性肾损伤具有肾脏保护作用。     

全反式维甲酸抑制核因子 E2相关因子 2和血红素加氧酶 1加重大鼠肾脏缺血再灌注损伤表达

目的观察用全反式维甲酸( all-trans retinoic acid,ATRA)抑制核因子 E2相关因子 2(Nrf2)和血红素加氧酶 1(HO-1)是否会加重大鼠肾脏缺血再灌注损伤( IRI)表达。方法 2020年 10月至 2022年 2月选取 24只健康成年雄性 SD大鼠切除右肾,并按随机数字表法分为 3组( n=8),即假手术组( Sham)、肾脏缺血再灌注( I/R)组、全反式维甲酸( I/R+ATRA)组。其中 Sham组和 I/R组给予腹腔注射玉米油( 1 mL·kg?1·d?1)1周, ATRA组则给予腹腔注射溶于玉米油的 ATRA(10 mg·kg?1·d?1)1周后, 3组大鼠用 10%的水合氯醛( 0.3 mL/100 g)进行麻醉后固定四肢,将其在 37 ℃条件下沿腹中线打开腹腔并分离出左肾动脉。其中 Sham组切除右肾,不予以夹闭左肾动脉; I/R组和 ATRA组采用右肾切除联合左肾动脉夹闭 45 min后再灌注 24 h的方法建立大鼠肾脏 I/R模型。实验结束后收集 3组大鼠血清及肾组织标本,用比色法检测血清肌酐(Scr)、血尿素氮(BUN)浓度; HE染色法观察肾组织病理改变; TUNEL法进行肾组织细胞凋亡的检测;二氢乙啶( DHE)荧光染色评估肾组织活性氧的表达情况;通过比色法检测肾组织丙二醛( MDA)浓度、超氧化物歧化酶( SOD)活性;用蛋白质印迹法分别对 Nrf2、HO-1的表达进行检测。结果与 Sham组相比, I/R组大鼠肾组织 Nrf2、HO-1蛋白表达量均增加( P<0.01)活性氧表达量增加, SOD活性下降, MDA含量、血清 Scr、BUN浓度升高( P<0.01)肾小管损伤评分及凋亡细胞表达较高(P<0.05),其中 Nrf2蛋白和 HO-1蛋白分别为 0.52±0.09和 0.37±0.79,高于Sham组的0.06±,0.01和 0.02±0.01。与 I/R组相比, I/R+ATRA组大,鼠肾组织 Nrf2、HO-1蛋白显著减少( P<0.01)活性氧表达量明显增加, SOD活性严重下降, MDA含量、血清 Scr、BUN浓度明显升高( P<0.01)肾小管损伤评分显著增加,凋亡细胞表达亦增高( P<0.05)其中 I/R+ATRA组 Nrf2蛋白和 HO-1蛋白分别为 0.29±0.04.15±0.03,显著低于 I/R组。结论 Nrf2/HO-1通路参与肾脏缺灌注损伤过程, ATRA可能通过抑制 Nrf2/HO-1通路,加重氧化应激,进一步加重肾肾脏,和0,血再,     

Yiguanjian decoction inhibits macrophage M1 polarization and attenuates hepatic fibrosis induced by CCl4/2-AAF

ContextOur previous studies indicated that Yiguanjian decoction (YGJ) has an anti-hepatic-fibrosis effect and could regulate macrophage status.ObjectiveTo elucidate the mechanism of YGJ in regulating macrophages.Materials and methodsLiver cirrhosis was induced by CCl₄ for 12 weeks combined with 2-acetylaminofluorene (2-AAF) for the last 4 weeks in male Wistar rats. YGJ (3.56 mg/kg) orally administered in the last 4 weeks, and SORA (1 mg/kg) as control. In vitro, RAW264.7 cells were treated with lipopolysaccharides (LPSs) to induce macrophage polarization to the M1 phenotype, and they were co-cultured with WB-F344 cells and allocated to M group, YGJ group (2 μg/mL) and WIF-1 group (1 μg/mL) with untreated cells as control. The differentiation direction of WB-F344 cell line was observed in the presence or absence of YGJ. Pathology, fibrosis-related cytokines, macrophage polarization-related components, and Wnt signalling pathway components were detected.ResultsIn vivo, the expression levels of α-SMA, Col (1), OV6, SOX9, EpCAM and M1 macrophage-related components (STAT1, IRF3, IRF5, IRF8, SOCS3) significantly decreased in the YGJ group compared with those in the 2-AAF/CCl₄ group (p < 0.01 or 0.05). In vitro, the expression levels of M1 macrophage-related components, including STAT1, NF-κB, IRF3, IRF5, and SOCS3, in RAW264.7 cells decreased significantly in the YGJ group compared with those in the M group (p < 0.05 or p < 0.01). The expression levels of Wnt3A, FZD5, LRP-5/-6, and β-catenin significantly increased in the YGJ group compared with those in the M group (p < 0.05 or p < 0.01). In addition, the expression levels of Wnt-4/-5A/-5B, and FZD2 significantly decreased in the YGJ group compared with those in the M group (p < 0.05 or p < 0.01).ConclusionThis study suggests that the anti-cirrhosis effect of YGJ is associated with its ability to inhibit macrophage M1-polarization, which provides a scientific basis for the clinical application of YGJ.     

Metformin attenuates renal fibrosis in both AMPKα2‐dependent and independent manners

Metformin is a well‐known AMP ‐activated protein kinase (AMPK ) activator, and it has been shown to inhibit organ fibrosis. Whether AMPK α2 mediates metformin protection against renal fibrosis remains unknown. Here, we aimed to investigate the role of the AMPK α2 isoform in mediating the inhibitory effect of metformin on renal fibrosis. Unilateral ureteral obstruction (UUO ) was used to induce renal fibrosis in wild‐type (WT ) and AMPK α2 knockout (AMPK α2^?/?) mice. Metformin treatment was initiated 3 days before UUO and was continued until 7 days after UUO . In WT mice, metformin significantly inhibited UUO ‐induced renal fibrosis. In AMPK α2^?/? mice, metformin also tended to inhibit UUO ‐induced renal fibrosis. Specifically, metformin significantly reduced UUO ‐induced transforming growth factor β1 (TGF β1) mRNA and protein expression in WT mice but not in AMPK α2^?/? mice. In contrast, metformin reduced UUO ‐induced TGF β1 downstream Smad3 phosphorylation in both WT and AMPK α2^?/? mice, suggesting that this regulation occurs in an AMPK α2‐independent manner. In conclusion, the underlying mechanisms for the protective effects of metformin against renal fibrosis include AMPK α2‐dependent targeting of TGF β1 production and AMPK α2‐independent targeting of TGF β1 downstream signalling. In this regard, metformin has an advantage over other AMPK activators for the treatment of renal fibrosis.     

C1q/TNF-related protein 6 (CTRP6) attenuates renal ischaemia-reperfusion injury through the activation of PI3K/Akt signalling pathway

C1q/TNF-related protein 6 (CTRP6) is a member of the CTRP family that has been reported to exhibit a nephroprotective effect. However, the role of CTRP6 in renal ischaemia/reperfusion (I/R) injury (IRI) remains unclear. In the present study, we aimed to explore the protective effect of CTRP6 in renal IRI and the potential mechanism. We found that CTRP6 expression was markedly decreased in the kidneys of mice subjected to I/R and HK-2 cells in response to hypoxia/reoxygenation (H/R) stimulation. Recombinant CTRP6 protein protected against renal I/R injury by the reduction of blood urea nitrogen (BUN) and creatinine levels. The increased production of ROS and malondialdehyde (MDA), as well the decreased activities of glutathione peroxidase (GPx) and superoxide dismutase (SOD) caused by H/R induction were mitigated by CTRP6 in HK-2 cells. The caspase-3 activity and apoptotic rate were both decreased in CTRP6-overexpressing HK-2 cells. In addition, we also found that knockdown of CTRP6 aggravated H/R-caused oxidative stress and cell apoptosis in HK-2 cells. Moreover, CTRP6 overexpression enhanced the H/R-stimulated activation of PI3K/Akt pathway in HK-2 cells. Inhibition of PI3K reversed the nephroprotective effects of CTRP6 in HK-2 cells. Taken together, CTRP6 exerted protective effects against H/R-caused oxidative injury in HK-2 cells via activating the PI3K/Akt pathway.     

MRP-1 expression levels determine strain-specific susceptibility to sodium arsenic-induced renal injury between C57BL/6 and BALB/c mice

To clarify the pathophysiological mechanism underlying acute renal injury caused by acute exposure to arsenic, we subcutaneously injected both BALB/c and C57BL/6 mice with sodium arsenite (NaAs; 13.5 mg/kg). BALB/c mice exhibited exaggerated elevation of serum blood urea nitrogen (BUN) and creatinine (CRE) levels, compared with C57BL/6 mice. Moreover, half of BALB/c mice died by 24 h, whereas all C57BL/6 mice survived. Histopathological examination on kidney revealed severe hemorrhages, acute tubular necrosis, neutrophil infiltration, cast formation, and disappearance of PAS-positive brush borders in BALB/c mice, later than 10 h. These pathological changes were remarkably attenuated in C57BL/6 mice, accompanied with lower intrarenal arsenic concentrations, compared with BALB/c mice. Among heavy metal inducible proteins including multidrug resistance-associated protein (MRP)-1, multidrug resistance gene (MDR)-1, metallothionein (MT)-1, and arsenite inducible, cysteine- and histidine-rich RNA-associated protein (AIRAP), intrarenal MDR-1, MT-1, and AIRAP gene expression was enhanced to a similar extent in both strains, whereas NaAs challenge augmented intrarenal MRP-1 mRNA and protein expression levels in C57BL/6 but not BALB/c mice. Moreover, the administration of a specific inhibitor of MRP-1, MK-571, significantly exaggerated acute renal injury in C57BL/6 mice. Thus, MRP-1 is crucially involved in arsenic efflux and eventually prevention of acute renal injury upon acute exposure to NaAs.     

比索洛尔预处理通过调控ERK1/2途径抑制缺氧/复氧诱导的心肌细胞凋亡和纤维化

目的 探讨比索洛尔预处理对缺氧/复氧诱导的心肌细胞凋亡和纤维化的影响,并分析分子机制。方法 构建缺氧/复氧细胞模型,将H9c2细胞分为对照组、模型组、比索洛尔组、细胞外信号调节激酶（ERK1/2）通路激活剂（LM22B-10）组。采用酶联免疫吸附测定法（ELISA）检测细胞中乳酸脱氢酶（LDH）和肌酸激酶同工酶（CK-MB）水平,CCK-8法检测细胞活力,流式细胞术检测细胞凋亡水平,免疫印迹法（Western blotting）法检测凋亡蛋白、纤维化蛋白和ERK1/2信号通路蛋白表达。结果 与模型组比较,比索洛尔组H9c2细胞中LDH和CK-MB水平、细胞凋亡率,切割型半胱氨酸天冬氨酸蛋白水解酶-3（cleaved Caspase-3）、B淋巴细胞瘤-2相关蛋白（Bax）、I型胶原（Col I）、III型胶原（Col III）、α-平滑肌肌动蛋白（α-SMA）、基质金属蛋白酶9（MMP-9）蛋白表达以及磷酸化细胞外信号调节激酶1/2（p-ERK1/2）/（ERK1/2）比值显著降低;细胞活力,B淋巴细胞瘤2（Bcl2）、金属蛋白酶组织抑制因子1（TIMP-1）蛋白表达显著升高（P<0.05）。与比索洛尔组比较,LM22B-10组H9c2细胞中LDH和CK-MB水平、细胞凋亡率,Cleaved Caspase-3、Bax、Col I、Col III、α-SMA、MMP-9蛋白表达以及（p-ERK1/2）/（ERK1/2）比值均显著升高,细胞活力,Bcl-2、TIMP-1蛋白表达均显著降低（P<0.05）。结论 比索洛尔预处理通过抑制ERK1/2信号通路活化减轻缺氧/复氧诱导的心肌细胞凋亡和纤维化。     

Influence of bradykinin B1 and B2 receptors in the immune response triggered by renal ischemia–reperfusion injury

Bradykinin B1 receptors are exclusively expressed in inflamed tissues. For this reason, they have been related with the outcomes of several pathologies. Ischemia–reperfusion injury is caused by the activation of inflammatory and cytoprotective genes, such as macrophage chemoattractant protein-1 and heme oxygenase-1, respectively. This study was aimed to analyze the involvement of bradykinin B1 and B2 receptors (B1R and B2R) in tissue response after renal ischemia–reperfusion injury. For that, B1R (B1−/−), B2R (B2−/−) knockout animals and its control (wild-type mice, B1B2+/+) were subjected to renal bilateral ischemia, followed by 24, 48 and 120 h of reperfusion. At these time points, blood serum samples were collected for creatinine and urea dosages. Kidneys were harvested for histology and molecular analyses by real-time PCR. At 24 and 48 h of reperfusion, B1−/− group resulted in the lowest serum creatinine and urea levels, indicating less renal damage, which was proved by renal histology. Renal protection associated with B1−/− mice was also related with higher expression of HO-1 and lower expression of MCP-1. In conclusion, the absence of B1R had a protective role against inflammatory responses developed after renal ischemia–reperfusion injury.     

Dose-dependent inhibition of CYP1A2, CYP2C19 and CYP2D6 by citalopram,fluoxetine, fluvoxamine and paroxetine

Objectives: The purpose of this pharmacokinetic study was to investigate the dose-dependent inhibition of model substrates for CYP2D6, CYP2C19 and CYP1A2 by four marketed selective serotonin reuptake inhibitors (SSRIs): citalopram, fluoxetine, fluvoxamine and paroxetine. Methods: The study was carried out as an in vivo single-dose study including 24 young, healthy men. All volunteers had been identified as sparteine- and mephenytoin-extensive metabolisers. The volunteers received in randomised order, at weekly intervals, increasing single oral doses of one of the four SSRIs, followed 3 h later by sparteine (CYP2D6), mephenytoin (CYP2C19) and caffeine (CYP1A2) tests. Fluoxetine was given at 3-week intervals because of the long half-life of fluoxetine and its metabolite norfluoxetine. Citalopram, fluoxetine and paroxetine were given in doses of 10, 20, 40 and 80 mg and fluvoxamine was given in doses of 25, 50, 100 and 200 mg. Results: With increasing doses, there was a statistically significant increase in the sparteine metabolic ratio (MR) (P < 0.01, Page’s test for trend) for all four SSRIs. The increase was modest after intake of citalopram and fluvoxamine, while the increase was more pronounced after fluoxetine intake, although no volunteers changed phenotype from extensive metabolisers to poor metabolisers. Three of the six volunteers changed phenotype from extensive metabolisers to poor metabolisers after intake of 40 or 80 mg paroxetine. There was a statistically significant increase in the mephenytoin S/R ratio (P < 0.01, Page’s test for trend) with increasing doses of fluoxetine and fluvoxamine, but not after citalopram and paroxetine. However, no volunteers changed phenotype from extensive to poor metabolisers of S-mephenytoin. After intake of fluvoxamine, the urinary excretion of the metabolites related to N3 demethylation of caffeine were below the limit of quantification, whereas there were no significant changes in the urinary caffeine metabolic ratios after intake of the other three SSRIs. Conclusion: This investigation confirms that paroxetine and fluoxetine are potent inhibitors of CYP2D6, that fluvoxamine and fluoxetine are moderate inhibitors of CYP2C19 and that fluvoxamine is a potent inhibitor of CYP1A2 in humans in vivo. The clinical prediction of interaction from single-dose experiments may have to take the degree of accumulation during steady-state after multiple doses into account. Received: 11 December 1995/Accepted in revised form: 29 February 1996     

Akebia Saponin D ameliorated kidney injury and exerted anti-inflammatory and anti-apoptotic effects in diabetic nephropathy by activation of NRF2/HO-1 and inhibition of NF-KB pathway

Diabetic nephropathy (DN), a common microvascular complication of type 2 diabetes mellitus (T2DM), causes increasing mortality and morbidity due to its high prevalence and severe consequences. Hence, it is urgent to search for effective agents that provide new insights into novel molecular therapeutic targets for DN. This study was designed to investigate the critical role of Akebia saponin D (ASD) in kidney damage, inflammation and apoptosis of renal tubular cells in DN. To probe the protective effects of ASD on DN in vivo, diabetes mellitus model was established by intraperitoneal (ip) injection of STZ (60 mg/kg) for 5 days consecutively. Besides, HG-induced human renal tubular cells (HK-2) were used to analyze the defined effects and underlying mechanism of ASD on DN in vitro. Blood glucose, insulin, serum creatinine (Scr), blood urea nitrogen (BUN), renal injury, inflammation, oxidative stress and apoptosis of renal tubular cells were respectively measured and evaluated. ASD prevented kidney damage, improved renal function and inflammatory reaction, ameliorated oxidative stress and inhibited apoptosis of renal tubular cells in DN mice via activation of NRF2/HO-1 pathway and inhibition of NF-KB pathway.     

S-allylmercaptocysteine ameliorates lipopolysaccharide-induced acute lung injury in mice by inhibiting inflammation and oxidative stress via nuclear factor kappa B and Keap1/Nrf2 pathways

The garlic-derived organosulfur compound S-allylmercaptocysteine (SAMC) has been reported to exhibit anti-inflammatory and anti-oxidative activities, whereas its potential therapeutic effect on lipopolysaccharide (LPS)-induced acute lung injury (ALI) is unknown. In this study, we focused on exploring the therapeutic effects of SAMC on LPS-induced ALI mice and the involvement of underlying molecular mechanisms. BalB/c mice were treated with SAMC (10, 30 and 60 mg/kg) or positive control N-acetylcysteine (NAC, 500 mg/kg) by gavage after intratracheal instillation of LPS for 30 min and were sacrificed 24 h after LPS administration. Our results indicate that the treatment with SAMC not only ameliorated the histological changes but also decreased LPS-triggered lung edema. Moreover, SAMC displayed an anti-inflammatory effect through reducing inflammatory cells infiltration, myeloperoxidase (MPO) formation and inhibiting pro-inflammatory cytokines/mediator production including tumor necrosis factor alpha (TNF-α), interleukin-1β (IL-1β), interleukin-6 (IL-6), inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX2) via suppressing the activation of nuclear factor-kappaB (NF-κB) signaling pathway. Furthermore, SAMC attenuated oxidative stress evoked by LPS via diminishing malondialdehyde (MDA) formation and reversing glutathione (GSH) and superoxide dismutase (SOD) depletion. Meanwhile, SAMC up-regulated expressions of endogenous antioxidant/detoxifying proteins including heme oxygenase-1 (HO-1) and NAD(P)H: quinone oxidoreductase 1(NQO1) through reversing the suppression of Kelch-like ECH-associated protein 1 (Keap1)/nuclear factor erythroid-2 related factor 2 (Nrf2) signaling pathway. Our results demonstrate that SAMC effectively attenuated LPS-induced ALI which was largely dependent upon inhibition of inflammation and oxidative stress via NF-κB and Keap1/Nrf2 signaling pathways.     

Genistein promotes M1 macrophage apoptosis and reduces inflammatory response by disrupting miR-21/TIPE2 pathway

Cardiovascular diseases are a major cause of mortality, and vascular injury, a common pathological basis of cardiovascular disease, is deeply correlated with macrophage apoptosis and inflammatory response. Genistein, a type of phytoestrogen, exerts cardiovascular protective activities, but the underlying mechanism has not been fully elucidated. In this study, RAW264.7 cells were treated with genistein, lipopolysaccharide (LPS), nuclear factor-kappa B (NF-κB) inhibitor, and/or protein kinase B (AKT) agonist to determine the role of genistein in apoptosis and inflammation in LPS-stimulated cells. Simultaneously, high fat diet-fed C57BL/6 mice were administered genistein to evaluate the function of genistein on LPS-induced cardiovascular injury mouse model. Here, we demonstrated that LPS obviously increased apoptosis resistance and inflammatory response of macrophages by promoting miR-21 expression, and miR-21 downregulated tumor necrosis factor-α-induced protein 8-like 2 (TIPE2) expression by targeting the coding region. Genistein reduced miR-21 expression by inhibiting NF-κB, then blocked toll-like receptor 4 (TLR4) pathway and AKT phosphorylation dependent on TIPE2, resulting in inhibition of LPS. Our research suggests that miR-21/TIPE2 pathway is involved in M1 macrophage apoptosis and inflammatory response, and genistein inhibits the progression of LPS-induced cardiovascular injury at the epigenetic level via regulating the promoter region of Vmp1 by NF-κB.