scholarly journals HO-1/CO Maintains Intestinal Barrier Integrity through NF-κB/MLCK Pathway in Intestinal HO-1-/- Mice

2021 ◽  
Vol 2021 ◽  
pp. 1-19
Author(s):  
Zhenling Zhang ◽  
Lijing Zhang ◽  
Qiuping Zhang ◽  
Bojia Liu ◽  
Fang Li ◽  
...  
Keyword(s):  
Molecular Mechanisms ◽  
Intestinal Barrier ◽  
Heme Oxygenase 1 ◽  
Zinc Protoporphyrin ◽  
Barrier Integrity ◽  
Tnf Α ◽  
Intestinal Barrier Integrity ◽  
Deficient Mice

Background. Intestinal barrier injury is an important contributor to many diseases. We previously found that heme oxygenase-1 (HO-1) and carbon monoxide (CO) protect the intestinal barrier. This study is aimed at elucidating the molecular mechanisms of HO-1/CO in barrier loss. Materials and Methods. We induced gut leakiness by injecting carbon tetrachloride (CCl4) to wildtype or intestinal HO-1-deficient mice. In addition, we administrated tumor necrosis factor-α (TNF-α) to cells with gain- or loss-of-HO-1 function. The effects of HO-1/CO maintaining intestinal barrier integrity were investigated in vivo and in vitro. Results. Cobalt protoporphyrin and CO-releasing molecule-2 alleviated colonic mucosal injury and TNF-α levels; upregulated tight junction (TJ) expression; and inhibited epithelial IκB-α degradation and phosphorylation, NF-κB p65 phosphorylation, long MLCK expression, and MLC-2 phosphorylation after administration of CCl4. Zinc protoporphyrin completely reversed these effects. These findings were further confirmed in vitro, using Caco-2 cells with gain- or loss-of-HO-1-function after TNF-α. Pretreated with JSH-23 (NF-κB inhibitor) or ML-7 (long MLCK inhibitor), HO-1 overexpression prevented TNF-α-induced TJ disruption, while HO-1 shRNA promoted TJ damage even in the presence of JSH-23 or ML-7, thus suggesting that HO-1 dependently protected intestinal barrier via the NF-κB p65/MLCK/p-MLC-2 pathway. Intestinal HO-1-deficient mice further demonstrated the effects of HO-1 in maintaining intestinal barrier integrity and its relative mechanisms. Alleviated hepatic fibrogenesis and serum ALT levels finally confirmed the clinical significance of HO-1/CO repairing barrier loss in liver injury. Conclusion. HO-1/CO maintains intestinal barrier integrity through the NF-κB/MLCK pathway. Therefore, the intestinal HO-1/CO-NF-κB/MLCK system is a potential therapeutic target for diseases with a leaky gut.

scholarly journals Spermine Protects Intestinal Barrier Integrity Through Rac1/PLC-γ1 Signalling Pathway in Piglets

2020 ◽  
Author(s):  
Guangmang Liu ◽  
Xiaomei Xu ◽  
Caimei Wu ◽  
Gang Jia ◽  
Hua Zhao ◽  
...  
Keyword(s):  
Tight Junction ◽  
Intestinal Barrier ◽  
Signalling Pathway ◽  
Tight Junction Protein ◽  
Intestinal Integrity ◽  
Tnf Α ◽  
Junction Protein ◽  
Intestinal Barrier Integrity

Abstract Background: Weaning stress can lead to the disruption of tight junctions and increased intestinal permeabilty, which contributes to the initiation and development of many disease, such as Crohn’s disease and ulcerative colitis. Pigs are more ideal models for human studies than other animals. However, no information is found about the relationship of intestinal integrity and spermine supplementation in pigs. The objective of this study is to investigate whether spermine protects intestinal barrier integrity via Rac1/PLC-γ1 signalling pathway in piglets. Methods: In vivo, the piglets were categorised into the control group and the spermine group, which was fed with spermine at 0.4 mmol kg−1 body weight for 7 hours and 3, 6 and 9 days. In vitro, we examined whether spermine protects the intestinal barrier after TNF-α challenge through Ras-related C3 botulinum toxin substrate 1 (Rac1)/Phospho-lipase C-γ1 (PLC-γ1) signalling pathway. Results: In vivo study revealed that the spermine treatment upregulated tight junction protein mRNA levels and Rac1/PLC-γ1 signalling pathway gene expression in the jejunum of piglets. The serum D-lactate content was significantly reduced after spermine treatment (P < 0.05). In vitro study revealed that 0.1 μM spermine significantly increased the levels of tight junction protein expression, Rac1/PLC-γ1 signalling pathway and transepithelial electrical resistance, and decreased paracellular permeability (P < 0.05). Further experiments showed that spermine treatment increased the levels of tight junction protein expression, Rac1/PLC-γ1 signalling pathway and transepithelial electrical resistance, and decreased paracellular permeability compared with the NSC-23766 and U73122 treatment with spermine after TNF-α challenge (P < 0.05). Conclusion: spermine protects intestinal integrity through the Rac1/PLC-γ1 signalling pathway.

Kaposi sarcoma-associated herpesvirus (KSHV) induces heme oxygenase-1 expression and activity in KSHV-infected endothelial cells

Blood ◽  
2004 ◽  
Vol 103 (9) ◽  
pp. 3465-3473 ◽  
Author(s):  
Shane C. McAllister ◽  
Scott G. Hansen ◽  
Rebecca A. Ruhl ◽  
Camilo M. Raggo ◽  
Victor R. DeFilippis ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Heme Oxygenase ◽  
Cell Biology ◽  
Molecular Mechanisms ◽  
Expression Profiles ◽  
Kaposi Sarcoma ◽  
Heme Oxygenase 1 ◽  
Spindle Cell Proliferation

Abstract Kaposi sarcoma (KS) is the most common AIDS-associated malignancy and is characterized by angiogenesis and the presence of spindle cells. Kaposi sarcoma-associated herpesvirus (KSHV) is consistently associated with all clinical forms of KS, and in vitro infection of dermal microvascular endothelial cells (DMVECs) with KSHV recapitulates many of the features of KS, including transformation, spindle cell proliferation, and angiogenesis. To study the molecular mechanisms of KSHV pathogenesis, we compared the protein expression profiles of KSHV-infected and uninfected DMVECs. This comparison revealed that heme oxygenase-1 (HO-1), the inducible enzyme responsible for the rate-limiting step in heme catabolism, was up-regulated in infected endothelial cells. Recent evidence suggests that the products of heme catabolism have important roles in endothelial cell biology, including apoptosis and angiogenesis. Here we show that HO-1 mRNA and protein are up-regulated in KSHV-infected cultures. Comparison of oral and cutaneous AIDS-KS tissues with normal tissues revealed that HO-1 mRNA and protein were also up-regulated in vivo. Increased HO-1 enzymatic activity in vitro enhanced proliferation of KSHV-infected DMVECs in the presence of free heme. Treatment with the HO-1 inhibitor chromium mesoporphyrin IX abolished heme-induced proliferation. These data suggest that HO-1 is a potential therapeutic target for KS that warrants further study. (Blood. 2004;103: 3465-3473)

Role of NHE3 in the Maintenance of Intestinal Barrier Integrity in IL-10-Deficient Mice

2011 ◽  
Vol 140 (5) ◽  
pp. S-634-S-635
Author(s):  
Claire B. Larmonier ◽  
Daniel Laubitz ◽  
Alexis L. Bucknam ◽  
Robert D. Thurston ◽  
Faihza M. Hill ◽  
...  
Keyword(s):  
Intestinal Barrier ◽  
Barrier Integrity ◽  
Intestinal Barrier Integrity ◽  
Deficient Mice

scholarly journals A comprehensive protein–protein interactome for yeast PAS kinase 1 reveals direct inhibition of respiration through the phosphorylation of Cbf1

2014 ◽  
Vol 25 (14) ◽  
pp. 2199-2215 ◽  
Author(s):  
Desiree DeMille ◽  
Benjamin T. Bikman ◽  
Andrew D. Mathis ◽  
John T. Prince ◽  
Jordan T. Mackay ◽  
...  
Keyword(s):  
Glucose Homeostasis ◽  
Protein Modification ◽  
Molecular Mechanisms ◽  
Binding Partners ◽  
Pas Kinase ◽  
Protein Interactome ◽  
Deficient Mice

Per-Arnt-Sim (PAS) kinase is a sensory protein kinase required for glucose homeostasis in yeast, mice, and humans, yet little is known about the molecular mechanisms of its function. Using both yeast two-hybrid and copurification approaches, we identified the protein–protein interactome for yeast PAS kinase 1 (Psk1), revealing 93 novel putative protein binding partners. Several of the Psk1 binding partners expand the role of PAS kinase in glucose homeostasis, including new pathways involved in mitochondrial metabolism. In addition, the interactome suggests novel roles for PAS kinase in cell growth (gene/protein expression, replication/cell division, and protein modification and degradation), vacuole function, and stress tolerance. In vitro kinase studies using a subset of 25 of these binding partners identified Mot3, Zds1, Utr1, and Cbf1 as substrates. Further evidence is provided for the in vivo phosphorylation of Cbf1 at T211/T212 and for the subsequent inhibition of respiration. This respiratory role of PAS kinase is consistent with the reported hypermetabolism of PAS kinase–deficient mice, identifying a possible molecular mechanism and solidifying the evolutionary importance of PAS kinase in the regulation of glucose homeostasis.

scholarly journals Targeted Deletion of the Lipopolysaccharide (LPS)-binding Protein Gene Leads to Profound Suppression of LPS Responses Ex Vivo, whereas In Vivo Responses Remain Intact

1997 ◽  
Vol 186 (12) ◽  
pp. 2051-2056 ◽  
Author(s):  
Mark M. Wurfel ◽  
Brian G. Monks ◽  
Robin R. Ingalls ◽  
Russell L. Dedrick ◽  
Russell Delude ◽  
...  
Keyword(s):  
Lipid Transfer Protein ◽  
Ex Vivo ◽  
Binding Protein ◽  
Embryonic Stem ◽  
Cellular Responses ◽  
Tnf Α ◽  
Deficient Mice ◽  
Lps Binding

Gram-negative bacterial lipopolysaccharide (LPS) stimulates phagocytic leukocytes by interacting with the cell surface protein CD14. Cellular responses to LPS are markedly potentiated by the LPS-binding protein (LBP), a lipid-transfer protein that binds LPS aggregates and transfers LPS monomers to CD14. LBP also transfers LPS to lipoproteins, thereby promoting the neutralization of LPS. LBP present in normal plasma has been shown to enhance the LPS responsiveness of cells in vitro. The role of LBP in promoting LPS responsiveness in vivo was tested in LBP-deficient mice produced by gene targeting in embryonic stem cells. Whole blood from LBP-deficient animals was 1,000-fold less responsive to LPS as assessed by the release of tumor necrosis factor (TNF)-α. Blood from gene-targeted mice was devoid of immunoreactive LBP, essentially incapable of transferring LPS to CD14 in vitro, and failed to support cellular responses to LPS. These activities were restored by the addition of exogenous recombinant murine LBP to the plasma. Despite these striking in vitro findings, no significant differences in TNF-α levels were observed in plasma from wild-type and LBP-deficient mice injected with LPS. These data suggest the presence of an LBP-independent mechanism for responding to LPS. These LBP knockout mice may provide a tool for discovering the nature of the presumed second mechanism for transferring LPS to responsive cells.

Dendritic cell-derived IL-2 production is regulated by IL-15 in humans and in mice

Blood ◽  
2005 ◽  
Vol 105 (2) ◽  
pp. 697-702 ◽  
Author(s):  
Sonia Feau ◽  
Valeria Facchinetti ◽  
Francesca Granucci ◽  
Stefania Citterio ◽  
David Jarrossay ◽  
...  
Keyword(s):  
Dendritic Cells ◽  
T Cell ◽  
Molecular Mechanisms ◽  
Interleukin 2 ◽  
Adaptive Immune ◽  
Deficient Mice ◽  
Mouse System

Abstract Dendritic cells (DCs) are involved in the initiation and regulation of innate and adaptive immune responses. Several molecular mechanisms regulate these diverse DC functions, and we have previously reported that mouse dendritic cells (mDCs) can produce interleukin-2 (IL-2) in vitro and in vivo, in response to microbial activation and T-cell-mediated stimuli. This property is shared by different DC subtypes, including Langerhans cells. Here we show that, on appropriate stimulation, human DCs, both plasmacytoid and myeloid subtypes, also express IL-2. Interestingly, the production of IL-2 by myeloid DCs is induced by T-cell-mediated stimuli and depends on the presence of IL-15. The key role of this cytokine in regulating IL-2 production was also confirmed in the mouse system. In particular, we could show that DCs from IL-15-deficient mice were strongly impaired in the ability to produce IL-2 after interactions with different microbial stimuli. Our results indicate that DC-produced IL-2 is tightly coregulated with the expression of IL-15.

scholarly journals Polygonatum sibiricum Polysaccharides Protect against MPP-Induced Neurotoxicity via the Akt/mTOR and Nrf2 Pathways

2021 ◽  
Vol 2021 ◽  
pp. 1-13
Author(s):  
Si Huang ◽  
Haiyan Yuan ◽  
Wenqun Li ◽  
Xinyi Liu ◽  
Xiaojie Zhang ◽  
...  
Keyword(s):  
Molecular Mechanisms ◽  
Neuronal Loss ◽  
Heme Oxygenase 1 ◽  
Related Factor ◽  
Dependent Manner ◽  
Quinone Oxidoreductase ◽  
Glutamate Cysteine Ligase ◽  
Dopaminergic Neuronal Loss

Polygonatum sibiricum, a well-known life-prolonging tonic in Chinese medicine, has been widely used for nourishing nerves in the orient, but the underlying molecular mechanisms remain unclear. In this study, we found that P. sibiricum polysaccharides (PSP) ameliorated 1-methyl-4-phenyl-1,2.3,6-tetrahydropyridine- (MPTP-) induced locomotor activity deficiency and dopaminergic neuronal loss in an in vivo Parkinson’s disease (PD) mouse model. Additionally, PSP pretreatment inhibited N-methyl-4-phenylpyridine (MPP+) induced the production of reactive oxygen species, increasing the ratio of reduced glutathione/oxidized glutathione. In vitro experiments showed that PSP promoted the proliferation of N2a cells in a dose-dependent manner, while exhibiting effects against oxidative stress and neuronal apoptosis elicited by MPP+. These effects were found to be associated with the activation of Akt/mTOR-mediated p70S6K and 4E-BP1 signaling pathways, as well as nuclear factor erythroid 2-related factor 2- (Nrf2-) mediated NAD(P)H quinone oxidoreductase 1 (NQO1), heme oxygenase-1 (HO-1), glutamate-cysteine ligase catalytic subunit (Gclc), and glutamate-cysteine ligase modulatory subunit (Gclm), resulting in antiapoptotic and antioxidative effects. Meanwhile, PSP exhibited no chronic toxicity in C57BJ/6 mice. Together, our results suggest that PSP can serve as a promising therapeutic candidate with neuroprotective properties in preventing PD.

scholarly journals Nrf2 Regulation by Curcumin: Molecular Aspects for Therapeutic Prospects

Molecules ◽  
2021 ◽  
Vol 27 (1) ◽  
pp. 167
Author(s):  
Seyed Hossein Shahcheraghi ◽  
Fateme Salemi ◽  
Niloufar Peirovi ◽  
Jamshid Ayatollahi ◽  
Waqas Alam ◽  
...  
Keyword(s):  
Molecular Mechanisms ◽  
Heme Oxygenase 1 ◽  
Related Factor ◽  
Glutamate Cysteine Ligase ◽  
Response Elements ◽  
Nrf2 Signaling Pathway ◽  
Anti Inflammatory ◽  
Molecular Aspects

Nuclear factor erythroid 2 p45-related factor (2Nrf2) is an essential leucine zipper protein (bZIP) that is primarily located in the cytoplasm under physiological conditions. Nrf2 principally modulates endogenous defense in response to oxidative stress in the brain.In this regard, Nrf2 translocates into the nucleus and heterodimerizes with the tiny Maf or Jun proteins. It then attaches to certain DNA locations in the nucleus, such as electrophile response elements (EpRE) or antioxidant response elements (ARE), to start the transcription of cytoprotective genes. Many neoplasms have been shown to have over activated Nrf2, strongly suggesting that it is responsible for tumors with a poor prognosis. Exactly like curcumin, Zinc–curcumin Zn (II)–curc compound has been shown to induce Nrf2 activation. In the cancer cell lines analyzed, Zinc–curcumin Zn (II)–curc compound can also display anticancer effects via diverse molecular mechanisms, including markedly increasing heme oxygenase-1 (HO-1) p62/SQSTM1 and the Nrf2 protein levels along with its targets. It also strikingly decreases the levels of Nrf2 inhibitor, Kelch-like ECH-associated protein 1 (Keap1) protein.As a result, the crosstalk between p62/SQSTM1 and Nrf2 could be used to improve cancer patient response to treatments. The interconnected anti-inflammatory and antioxidative properties of curcumin resulted from its modulatory effects on Nrf2 signaling pathway have been shown to improve insulin resistance. Curcumin exerts its anti-inflammatory impact through suppressing metabolic reactions and proteins such as Keap1 that provoke inflammation and oxidation. A rational amount of curcumin-activated antioxidant Nrf2 HO-1 and Nrf2-Keap1 pathways and upregulated the modifier subunit of glutamate-cysteine ligase involved in the production of the intracellular antioxidant glutathione. Enhanced expression of glutamate-cysteine ligase, a modifier subunit (GLCM), inhibited transcription of glutamate-cysteine ligase, a catalytic subunit (GCLC). A variety of in vivo, in vitro and clinical studies has been done so far to confirm the protective role of curcumin via Nrf2 regulation. This manuscript is designed to provide a comprehensive review on the molecular aspects of curcumin and its derivatives/analogs via regulation of Nrf2 regulation.

Tanshinone I Exerts Cardiovascular Protective Effects in Vivo and in Vitro Through Inhibiting Necroptosis via Akt/nrf2 Signaling Pathway

2021 ◽  
Author(s):  
Youqiong Zhuo ◽  
Renyikun Yuan ◽  
Xinxin Chen ◽  
Jia He ◽  
Yangling Chen ◽  
...  
Keyword(s):  
Protective Effect ◽  
Enzyme Linked Immunosorbent Assay ◽  
Heme Oxygenase 1 ◽  
Protective Agent ◽  
H9c2 Cells ◽  
Cardiovascular Protection ◽  
Tnf Α ◽  
Nrf2 Signaling Pathway

Abstract BackgroundTanshinone I (TI) is a primary component of Salvia miltiorrhiza Bunge (Danshen), which confers a favorable role in a variety of pharmacological activities including cardiovascular protection. However, the exact mechanism of the cardiovascular protection activity of TI remains to be illustrated. In this study, the cardiovascular protective effect and its mechanism of TI were investigated.MethodsIn this study, tert-butyl hydroperoxide (t-BHP)-stimulated H9c2 cells model was employed to investigate the protective effect in vitro. The cell viability was determined by 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyl tetrazolium bromide (MTT) assay and lactate dehydrogenase (LDH) kit. The reactive-oxygen-species (ROS) level and mitochondrial membrane potential (MMP) were investigated by the flow cytometry and JC-1 assay, respectively. While in vivo experiment, the cardiovascular protective effect of TI was determined by using myocardial ischemia-reperfusion (MI/R) model including hematoxylin-eosin (H&E) staining assay and determination of superoxide dismutase (SOD) and malondialdehyde (MDA). Tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) release were detected by Enzyme-linked immunosorbent assay (ELISA). All related protein expression was determined by western blotting.ResultsOur data demonstrated that TI pretreatment attenuated t-BHP- and MI/R injury-induced necroptosis by inhibiting the expression of p-RIP1, p-RIP3, and p-MLKL. TI activated the Akt/Nrf2 pathway to promote the expression of antioxidant-related proteins such as phosphorylation of Akt, nuclear factor erythroid 2 related factor 2 (Nrf2), quinone oxidoreductase-1 (NQO-1) and heme oxygenase-1 (HO-1) expression in t-BHP-stimulated H9c2 cells. TI relieved oxidative stress by mitigating ROS generation and reversing MMP loss. In vivo experiment, TI made electrocardiograph (ECG) recovery better and lessened the degree of myocardial tissue damage. The counts of white blood cell (WBC), neutrophil (Neu), lymphocyte (Lym), and the release of TNF-α and IL-6 were reversed by TI treatment. SOD level was increased, while MDA level was decreased by TI treatment.ConclusionCollectively, our findings indicated that TI exerted cardiovascular protective activities in vitro and in vivo through suppressing RIP1/RIP3/MLKL and activating Akt/Nrf2 signaling pathways, which could be developed into a cardiovascular protective agent.

scholarly journals The Promising Effects of Astaxanthin on Lung Diseases

2020 ◽  
Author(s):  
Junrui Cheng ◽  
Abdulkerim Eroglu
Keyword(s):  
Lung Cancer ◽  
Lung Diseases ◽  
Molecular Mechanisms ◽  
Janus Kinase ◽  
In Vivo Studies ◽  
Chronic Obstructive ◽  
Heme Oxygenase 1 ◽  
Related Factor

ABSTRACT Astaxanthin (ASX) is a naturally occurring xanthophyll carotenoid. Both in vitro and in vivo studies have shown that it is a potent antioxidant with anti-inflammatory properties. Lung cancer is the leading cause of cancer death worldwide, whereas other lung diseases such as chronic obstructive pulmonary disease, emphysema, and asthma are of high prevalence. In the past decade, mounting evidence has suggested a protective role for ASX against lung diseases. This article reviews the potential role of ASX in protecting against lung diseases, including lung cancer. It also summarizes the underlying molecular mechanisms by which ASX protects against pulmonary diseases, including regulating the nuclear factor erythroid 2–related factor/heme oxygenase-1 pathway, NF-κB signaling, mitogen-activated protein kinase signaling, Janus kinase–signal transducers and activators of transcription-3 signaling, the phosphoinositide 3-kinase/Akt pathway, and modulating immune response. Several future directions are proposed in this review. However, most in vitro and in vivo studies have used ASX at concentrations that are not achievable by humans. Also, no clinical trials have been conducted and/or reported. Thus, preclinical studies with ASX treatment within physiological concentrations as well as human studies are required to examine the health benefits of ASX with respect to lung diseases.

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