scholarly journals The Decrease in Farnesoid X Receptor, Pregnane X Receptor and Constitutive Androstane Receptor in the Liver after Intestinal Ischemia-Reperfusion

2012 ◽  
Vol 15 (5) ◽  
pp. 616 ◽  
Author(s):  
Jiro Ogura ◽  
Yusuke Terada ◽  
Takashi Tsujimoto ◽  
Takahiro Koizumi ◽  
Kaori Kuwayama ◽  
...  

Purpose. Intestinal ischemia-reperfusion (I/R) damages remote organs, including the liver, and promotes multi-organ failure (MOF). However, the molecular mechanisms underlying acute liver injury after intestinal I/R have not been completely elucidated. Farnesoid X receptor (FXR), pregnane X receptor (PXR) and constitutive androstane receptor (CAR) regulate metabolizing enzymes and transporters, and coordinately prevent hepatotoxicity reflecting an inability of appropriate excretion of endogenous toxic compounds. In this study, we assessed FXR, PXR and CAR expression levels and their localization levels in nuclei in the liver after intestinal I/R. We also investigated the effect of IL-6 on FXR, PXR and CAR expression levels and their localization levels in nuclei in in vitro experiments. Methods. We used intestinal I/R model rats. Moreover, HepG2 cells were used in in vitro study. Real-time PCR and Western blotting were used to assess mRNA and protein expression levels. Nuclear receptor localization in nuclei was analyzed by Western blotting using nuclear extracts. Results. FXR and PXR expression levels began to be decreased at 3 h, and FXR, PXR and CAR expression levels were decreased at 6 h after intestinal I/R. The localization levels of FXR, PXR and CAR in nuclei began to be decreased at 3 h, and all of them were decreased at 6 h after intestinal I/R. In HepG2 cells, FXR, PXR and CAR expression levels were decreased by 0.5-1 ng/mL, 0.5-100 ng/mL and 100 ng/mL IL-6 treatment for 24 h, respectively. FXR, PXR and CAR localization levels in nuclei were suppressed by 0.5-10 ng/mL, 10-100 ng/mL and 10-100 ng/mL IL-6 treatment for 24 h, respectively. Conclusions. FXR, PXR and CAR expression levels are decreased in the liver after intestinal I/R. IL-6 is one of main causes the decreases in expressions of these receptors. This article is open to POST-PUBLICATION REVIEW. Registered readers (see “For Readers”) may comment by clicking on ABSTRACT on the issue’s contents page.

2021 ◽  
Vol 2021 ◽  
pp. 1-13
Author(s):  
Daili Chen ◽  
Chaojin Chen ◽  
Xue Xiao ◽  
Ziyan Huang ◽  
Xiaolei Huang ◽  
...  

Background. Intestinal ischemia is a common clinical critical illness. Intestinal ischemia-reperfusion (IIR) leads to acute lung injury (ALI), but the causative factors of ALI are unknown. The aim of this study was to reveal the causative factors and mechanisms of IIR-induced lung injury. Methods. A mouse model of IIR was developed using C57BL/6 mice, followed by detection of lung injury status and plasma levels of inflammatory factors in sham-operated mice and model mice. Some model mice were treated with a tumor necrosis factor-α (TNF-α) inhibitor lenalidomide (10 mg/kg), followed by observation of lung injury status through hematoxylin and eosin staining and detection of neutrophil infiltration levels through naphthol esterase and Ly6G immunohistochemical staining. Additionally, peripheral blood polymorphonuclear neutrophils (PMNs) were cultured in vitro and then stimulated by TNF-α to mimic in vivo inflammatory stimuli; this TNF-α stimulation was also performed on PMNs after knockdown of FoxO3a or treatment with the c-Jun N-terminal kinase (JNK) inhibitor SP600125. PMN apoptosis after stimulation was detected using flow cytometry. Finally, the role of PMN apoptosis in IIR-induced lung injury was evaluated in vivo by detecting the ALI status in the model mice administered with ABT-199, a Bcl-2 inhibitor. Results. IIR led to pulmonary histopathological injury and increased lung water content, which were accompanied by increased plasma levels of inflammatory factors, with the TNF-α plasma level showing the most pronounced increase. Inhibition of TNF-α led to effective reduction of lung tissue injury, especially that of the damaging infiltration of PMNs in the lung. In vitro knockdown of FoxO3a or inhibition of JNK activity could inhibit TNF-α-induced PMN apoptosis. Further in vivo experiments revealed that ABT-199 effectively alleviated lung injury and decreased inflammation levels by promoting PMN apoptosis during IIR-induced lung injury. Conclusion. TNF-α activates the JNK/FoxO3a pathway to induce a delay in PMN apoptosis, which promotes IIR-induced lung injury.


2009 ◽  
Vol 296 (5) ◽  
pp. G1119-G1129 ◽  
Author(s):  
Pilar Martínez-Fernández ◽  
Loreto Hierro ◽  
Paloma Jara ◽  
Luis Alvarez

Farnesoid X receptor (FXR) is a bile acid-sensing nuclear receptor that controls bile acid homeostasis. It has been suggested that downregulation of FXR contributes to the pathogenesis of an inherited disorder of bile secretion caused by mutations in ATP8B1. We have investigated the relationship between ATP8B1 knockdown and FXR downregulation in the human hepatoblastoma cell line HepG2. Transfection of HepG2 cells with ATP8B1 small interfering RNA (siRNA) duplexes led to a 60% reduction in the endogenous levels of ATP8B1 mRNA and protein and a concomitant decrease in FXR mRNA and protein content, as well as in FXR phosphorylation. This decrease was accompanied by a marked reduction in mRNA levels of a subset of FXR targets, such as bile salt export pump ( ABCB11), small heterodimer partner, and uridine 5′-diphosphate-glucuronosyltransferase. ATP8B1 inhibition specifically targeted FXR since mRNA expression of other prominent nuclear receptors, such as pregnane X receptor and constitutive androstane receptor, or liver-enriched transcription factors, such as hepatocyte nuclear factor 1α ( HNF-1α) and HNF-4α, was not altered. The expression of other key genes involved in bile acid synthesis, detoxification, and transport also remained unchanged upon ATP8B1 knockdown. Supporting the specificity of the effect, siRNA-mediated silencing of ABCB11, whose defect is associated with another inherited disorder of bile secretion, did not affect FXR expression. Treatment with the synthetic FXR agonist GW4064 was able to partially neutralize ATP8B1 siRNA-mediated FXR downregulation and fully counteract inhibition of FXR target genes. Collectively these findings indicate that ATP8B1 knockdown specifically downregulates FXR, and this action can be circumvented by treatment with FXR agonists.


2014 ◽  
Vol 17 (2) ◽  
pp. 266 ◽  
Author(s):  
Yusuke Terada ◽  
Jiro Ogura ◽  
Takashi Tsujimoto ◽  
Kaori Kuwayama ◽  
Takahiro Koizumi ◽  
...  

Purpose. Reactive oxygen species (ROS) have multiple physiological effects that are amount-dependent. ROS are one of the causes of intestinal ischemia-reperfusion (I/R) injury. In this study, we investigated whether the amount of ROS and the degree of intestinal I/R injury affect the expression level of P-glycoprotein (P-gp). Methods. We used hydrogen peroxide (H2O2) as ROS in in vitro experiments. Intestinal I/R model rats, which were subjected 15-min ischemia (I/R-15), were used in in vivo experiments. Results. P-gp expression in Caco-2 cells was increased in response to 1 µM of H2O2 but decreased upon exposure to 10 mM of H2O2. We previously reported that P-gp expression is decreased after intestinal I/R with 30-min ischemia (I/R-30), which time a large amount of ROS is generated. I/R-15 induced slightly less mucosal and oxidative injury than did I/R-30. P-gp expression in the jejunum was increased at 1 h after I/R-15, and ileal paracellular permeability was increased. The blood concentration of tacrolimus, a P-gp substrate, was lower during 0-20 min but was higher during 40-90 min post-administration compared with that in the sham-operated rats. P-gp expression in the ileum was decreased at 6 h after I/R-15, due to abnormal localization of P-gp, resulting in a high blood tacrolimus concentration in rats reperfused for 6 h. Conclusions. ROS multimodally regulate P-gp expression depending on its amount. This is important for understanding the pattern of P-gp expression after intestinal I/R. This article is open to POST-PUBLICATION REVIEW. Registered readers (see “For Readers”) may comment by clicking on ABSTRACT on the issue’s contents page.


2017 ◽  
Vol 131 (8) ◽  
pp. 759-773 ◽  
Author(s):  
Dongcheng Feng ◽  
Jihong Yao ◽  
Guangzhi Wang ◽  
Zhenlu Li ◽  
Guo Zu ◽  
...  

Intestinal epithelial oxidative stress and apoptosis constitute key pathogenic mechanisms underlying intestinal ischemia/reperfusion (I/R) injury. We previously reported that the adaptor 66 kDa isoform of the adaptor molecule ShcA (p66Shc)-mediated pro-apoptotic pathway was activated after intestinal I/R. However, the upstream regulators of the p66Shc pathway involved in intestinal I/R remain to be fully identified. Here, we focused on the role of a prolyl-isomerase, peptidyl–prolyl cis–trans isomerase (Pin1), in the regulation of p66Shc activity during intestinal I/R. Intestinal I/R was induced in rats by superior mesenteric artery (SMA) occlusion. Juglone (Pin1 inhibitor) or vehicle was injected intraperitoneally before I/R challenge. Caco-2 cells were exposed to hypoxia/reoxygenation (H/R) in vitro to simulate an in vivo I/R model. We found that p66Shc was significantly up-regulated in the I/R intestine and that this up-regulation resulted in the accumulation of intestinal mitochondrial reactive oxygen species (ROS) and massive epithelial apoptosis. Moreover, intestinal I/R resulted in elevated protein expression and enzyme activity of Pin1 as well as increased interaction between Pin1 and p66Shc. This Pin1 activation was responsible for the translocation of p66Shc to the mitochondria during intestinal I/R, as Pin1 suppression by juglone or siRNA markedly blunted p66Shc mitochondrial translocation and the subsequent ROS generation and cellular apoptosis. Additionally, Pin1 inhibition alleviated gut damage and secondary lung injury, leading to improvement of survival after I/R. Collectively, our findings demonstrate for the first time that Pin1 inhibition protects against intestinal I/R injury, which could be partially attributed to the p66Shc-mediated mitochondrial apoptosis pathway. This may represent a novel prophylactic target for intestinal I/R injury.


PLoS ONE ◽  
2017 ◽  
Vol 12 (1) ◽  
pp. e0169331 ◽  
Author(s):  
Laurens J. Ceulemans ◽  
Len Verbeke ◽  
Jean-Paul Decuypere ◽  
Ricard Farré ◽  
Gert De Hertogh ◽  
...  

2013 ◽  
Vol 16 (5) ◽  
pp. 722 ◽  
Author(s):  
Hajime Maruyama ◽  
Jiro Ogura ◽  
Asuka Fujikawa ◽  
Yusuke Terada ◽  
Takashi Tsujimoto ◽  
...  

Purpose. Intestinal ischemia-reperfusion (I/R) causes gut dysfunction and promotes multi-organ failure. The liver and kidney can be affected by multi-organ failure after intestinal I/R. Organic anion transporting polypeptides (OATPs) and organic anion transporters (OATs) are recognized in a broad spectrum from endogenous compounds to xenobiotics, including clinically important drugs. Therefore, it is important for understanding the pharmacokinetics to obtain evidence of alterations in OATPs and OATs expression and transport activities. In the present study, we investigated the expression of rat Oatps and Oats after intestinal I/R. Methods. We used intestinal ischemia-reperfusion (I/R) model rats. Real-time PCR and Western blotting were used to assess mRNA and protein expression levels. Plasma concentration and biliary excretion of sulfobromophthalein (BSP), which is used as a model compound of organic anion drugs, were measured after intravenous administration in intestinal I/R rats. Results. Although Oat1 and Oat3 mRNA levels were not altered in the kidney, Oatp1a1, Oatp1b2 and Oatp2b1 mRNA levels in the liver were significantly decreased at 1-6 h after intestinal I/R. Moreover, Oatp1a1 and Oatp2b1 protein expression levels were decreased at 1 h after intestinal I/R. Plasma concentration of BSP, which is a typical substrate of Oatps, in intestinal I/R rats reperfused 1 h was increased than that in sham-operated rats. Moreover, the area under the concentration-time curve (AUC0-90) in intestinal I/R rats reperfused 1 h was significantly increased than that in sham-operated rats. The total clearance (CLtot) and the biliary clearance (CLbile) in intestinal I/R rats reperfused 1 h were significantly decreased than those in sham-operated rats. Conclusions. Oatp1a1 and Oatp2b1 expression levels are decreased by intestinal I/R. The decreases in these transporters cause alteration of pharmacokinetics of organic anion compound. The newly found influence of intestinal I/R on the expression and function of Oatps may be a key to perform appropriate drug therapy.This article is open to POST-PUBLICATION REVIEW. Registered readers (see “For Readers”) may comment by clicking on ABSTRACT on the issue’s contents page


PLoS ONE ◽  
2019 ◽  
Vol 14 (1) ◽  
pp. e0211195 ◽  
Author(s):  
Rui Zhang ◽  
Guizhen He ◽  
Yukang Wang ◽  
Jie Wang ◽  
Wei Chen ◽  
...  

2021 ◽  
Author(s):  
Meng Wang ◽  
Yong Zhu ◽  
Shujuan Liu ◽  
Zhaochun Tian ◽  
Pengfei Zhu ◽  
...  

Abstract Background: This study was performed to determine the protection and molecular responses of Chinese medicine Qingchang mixture on intestinal ischemia-reperfusion (IR) injury.Methods: The rat intestinal IR model was prepared. Intestinal ischemic injury was evaluated by the HE staining, biochemical assay and western blot. In addition, human intestinal epithelial cells (IEC-6) hypoxia-reoxygenation (HR) in vitro model was prepared. The viability and apoptosis of IEC-6 cells were measured by CCK8 and apoptosis detection. TAK242 or PDTC was used as the small molecule inhibitor of TLR4 or NF-κB.Results: Compared with the IR group, the pretreatment of Qingchang mixture relieved the morphological damage, oxidative stress, inflammatory response and barrier function damage of small intestine tissue. IR significantly increased the expression of TLR4 and NF-κB, while the pretreatment of Qingchang mixture inhibited the expression of TLR4 and NF-κB. Furthermore, the pretreatment of Qingchang mixture, TAK242 or PDTC effectively improved the viability, and hindered apoptosis of the HR-induced IEC-6 cells.Conclusions: Chinese medicine Qingchang mixture prevents the intestinal IR injury through TLR4/NF-kB pathway.


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