scholarly journals Synergistic Inhibitory Effect of the Gut Microbiome and Lithocholic Acid on Liver Fibrosis

Author(s):  
Junwei Shao ◽  
Tiantian Ge ◽  
Senzhong Chen ◽  
Zhi Chen

Abstract Background: Lithocholic acid are essential signaling molecules that mediate the relationship between the gut microbiome and liver function by regulating inflammation. The purpose of this study is to investigate the role of lithocholic acid in liver fibrosis. Methods: A liver fibrosis mouse model was induced by carbon tetrachloride followed by gavage of lithocholic acid, and the effects of lithocholic acid were evaluated by serum biochemical analysis and liver histology. Plasma cytokine levels and the number of immune cells were determined by cytometric bead array and flow cytometry, respectively. Results: Lithocholic acid treatment increased the recruitment of NK cells and reduced the activation of NKT cells, and reduced M1 macrophages differentiation and increased M2 macrophages differentiation. Furthermore, the lithocholic acid prevented inflammatory liver disease by reducing TNF-α and IL-22 secretion. However, the effect of lithocholic acid disappeared when the host gut microbiome was treated with antibiotics. Conclusions: It showed that the activation of lithocholic acid-mediated signaling was linked to the inhibition of inflammation and improvement of liver fibrosis. The role of lithocholic acid in liver fibrosis is mediated by the gut microbiome. The association between the gut microbiome, lithocholic acid, and liver function can serve as a therapeutic target for liver fibrosis.

2021 ◽  
Vol 16 (1) ◽  
Author(s):  
Jianwei Zhang ◽  
Lei Han ◽  
Feng Chen

Abstract Background Let-7a-5p is demonstrated to be a tumor inhibitor in nasopharyngeal carcinoma. However, the role of let-7a-5p in chronic rhinosinusitis with nasal polyps (CRSwNP) has not been reported. This study is designed to determine the pattern of expression and role of let-7a-5p in CRSwNP. Methods The expression level of let-7a-5p, TNF-α, IL-1β, and IL-6 in CRSwNP tissues and cells were detected by RT-qPCR. Western blot assay was carried out to measure the protein expression of the Ras-MAPK pathway. Dual luciferase reporter assay and RNA pull-down assay were used to explore the relationship between let-7a-5p and IL-6. Results Let-7a-5p was significantly downregulated in CRSwNP tissues and cells. Moreover, the mRNA expression of TNF-α, IL-1β and IL-6 was increased in CRSwNP tissues, while let-7a-5p mimic inhibited the expression of TNF-α, IL-1β and IL-6. Besides that, let-7a-5p was negatively correlated with TNF-α, IL-1β and IL-6 in CRSwNP tissues. In our study, IL-6 was found to be a target gene of let-7a-5p. Additionally, let-7-5p mimic obviously reduced the protein levels of Ras, p-Raf1, p-MEK1 and p-ERK1/2, while IL-6 overexpression destroyed the inhibitory effect of let-7a-5p on the Ras-MAPK pathway in CRSwNP. Conclusion We demonstrated that let-7a-5p/IL-6 interaction regulated the inflammatory response through the Ras-MAPK pathway in CRSwNP.


2020 ◽  
Vol 22 (1) ◽  
pp. 199
Author(s):  
Na Young Lee ◽  
Ki Tae Suk

Liver cirrhosis is one of the most prevalent chronic liver diseases worldwide. In addition to viral hepatitis, diseases such as steatohepatitis, autoimmune hepatitis, sclerosing cholangitis and Wilson’s disease can also lead to cirrhosis. Moreover, alcohol can cause cirrhosis on its own and exacerbate chronic liver disease of other causes. The treatment of cirrhosis can be divided into addressing the cause of cirrhosis and reversing liver fibrosis. To this date, there is still no clear consensus on the treatment of cirrhosis. Recently, there has been a lot of interest in potential treatments that modulate the gut microbiota and gut-liver axis for the treatment of cirrhosis. According to recent studies, modulation of the gut microbiome by probiotics ameliorates the progression of liver disease. The precise mechanism for relieving cirrhosis via gut microbial modulation has not been identified. This paper summarizes the role and effects of the gut microbiome in cirrhosis based on experimental and clinical studies on absorbable antibiotics, probiotics, prebiotics, and synbiotics. Moreover, it provides evidence of a relationship between the gut microbiome and liver fibrosis.


2021 ◽  
Author(s):  
Shuang Zhang ◽  
Hui-Min Wu ◽  
Xiang-Ni Cao ◽  
Xian-Qi Zhang ◽  
Gui-ping Gao

Abstract Background: We investigated bilateral tear cytokine levels including interleukin (IL)-1β, IL-10, IL-17, tumor necrosis factor (TNF)-α and Matrix metalloproteinase-9 (MMP-9) in patients with fungal keratitis(FK). Meanwhile, we evaluated the relationship between the changes of tear cytokines with corneal perception and pain in infected eyes, and the relationship between tear cytokines and tear film function in contralateral uninfected eyes .Methods : A total of 60(20 FK, 20 contralateral, 20 healthy controls) tear samples were collected prospectively and analyzed by enzyme linked immunosorbent assay(ELISA). Approximately 50 to 60 ul of tear samples in each case were collected. Meanwhile ,we analyzed the changes of visual analogue scale(VAS), tear breakup time (TBUT), Schirmer I test (SIT) and corneal perception compared with healthy controls. Results :The concentrations of IL-1β, IL-10 and IL-17 increased in bilateral eyes compared with healthy controls(P<0.05). The tear concentrations of MMP-9 , TNF-α only significantly increased in affected eyes (P <0.05). Patients with FK showed significant reduction in corneal perception of infected eyes compared with controls(P<0.05). Corneal perception of the normal eyes in FK patients was slightly lower than that of control group, but there was not statistical difference (P>0.05).TBUT and SIT of contralateral uninfected eyes were significantly lower than that of control group(P<0.05), which were significantly correlated with levels of IL-1β, IL-17(P<0.05). SIT were also negatively correlated with MMP-9(P<0.05), while the levels of IL-1β, IL-10, IL-17, TNF-α and MMP-9 in the tears of the healthy control group had no significant correlation with TBUT and SIT indicators(P>0.05).The corneal perception and VAS score of the affected FK eyes showed correlation with IL-1β, IL-17 and TNF-α(P<0.05).In addition, concentration of IL-10 inversely was correlated with VAS (P<0.05). Conclusion: Proinflammatory tear cytokines are elevated in bilateral eyes with unilateral FK as associated with tear film function ,pain and corneal sensitivity.


2020 ◽  
Vol 18 (1) ◽  
Author(s):  
Junfeng Ye ◽  
Yuanqiang Lin ◽  
Ying Yu ◽  
Di Sun

Abstract Background Long non-coding RNA nuclear paraspeckle assembly transcript 1 (NEAT1) has been reported to play an essential role in non-alcoholic fatty liver disease. However, the role of NEAT1 in regulation of alcoholic steatohepatitis (ASH) remains largely unknown. This study aims to explore the role of NEAT1 in ASH by mediating microRNA-129-5p (miR-129-5p) targeting suppressor of cytokine signaling 2 (SOCS2). Methods NEAT1, miR-129-5p and SOCS2 expression in serum of ASH patients were assessed. In the in vitro cellular experiment, we transfected siRNAs, oligonucleotides or plasmids into ethanol-induced AML-12 mouse hepatocytes to alter NEAT1 and miR-129-5p expression, and inflammatory factors and lipid content were determined. In the in vivo animal experiment, we injected lentiviruses carrying siRNAs, oligonucleotides or plasmids onto ASH mice (ASH induced by feeding mice a Lieber-DeCarli ethanol diet) to alter NEAT1 and miR-129-5p expression through the tail vein. Serum liver function, blood lipids and inflammatory factors were detected; liver histopathology, liver cell apoptosis, and fibrosis were observed. The relationship between NEAT1 and miR-129-5p, or between miR-129-5p and SOCS2 was verified. Results MiR-129-5p was reduced while NEAT1 and SOCS2 were elevated in ASH. Inhibited NEAT1 or elevated miR-129-5p suppressed the elevated lipid metabolism and restrained inflammation reaction in ethanol-stimulated AML-12 cells. The promoted miR-129-5p and inhibited NEAT1 could improve the liver function and repress blood lipid, inflammation reaction, hepatocyte apoptosis and liver fibrosis in ethanol-induced ASH mice. Furthermore, NEAT1 could negatively regulate miR-129-5p to target SOCS2. Conclusion We have found that the inhibited NEAT1 could suppress liver fibrosis in ASH mice by promoting miR-129-5p and restraining SOCS2, thereby decelerating the development of ASH.


1998 ◽  
Vol 274 (1) ◽  
pp. L26-L31 ◽  
Author(s):  
Paul J. Jagielo ◽  
Timothy J. Quinn ◽  
Nilofer Qureshi ◽  
David A. Schwartz

To further determine the importance of endotoxin in grain dust-induced inflammation of the lower respiratory tract, we evaluated the efficacy of pentaacylated diphosphoryl lipid A derived from the lipopolysaccharide of Rhodobacter sphaeroides (RsDPLA) as a partial agonist of grain dust-induced airway inflammation. RsDPLA is a relatively inactive compound compared with lipid A derived from Escherichia coli (LPS) and has been demonstrated to act as a partial agonist of LPS-induced inflammation. To assess the potential stimulatory effect of RsDPLA in relation to LPS, we incubated THP-1 cells with RsDPLA (0.001–100 μg/ml), LPS (0.02 μg endotoxin activity/ml), or corn dust extract (CDE; 0.02 μg endotoxin activity/ml). Incubation with RsDPLA revealed a tumor necrosis factor (TNF)-α stimulatory effect at 100 μg/ml. In contrast, incubation with LPS or CDE resulted in TNF-α release at 0.02 μg/ml. Pretreatment of THP-1 cells with varying concentrations of RsDPLA before incubation with LPS or CDE (0.02 μg endotoxin activity/ml) resulted in a dose-dependent reduction in the LPS- or CDE-induced release of TNF-α with concentrations of RsDPLA of up to 10 μg/ml but not at 100 μg/ml. To further understand the role of endotoxin in grain dust-induced airway inflammation, we utilized the unique LPS inhibitory property of RsDPLA to determine the inflammatory response to inhaled CDE in mice in the presence of RsDPLA. Ten micrograms of RsDPLA intratracheally did not cause a significant inflammatory response compared with intratracheal saline. However, pretreatment of mice with 10 μg of RsDPLA intratracheally before exposure to CDE (5.4 and 0.2 μg/m3) or LPS (7.2 and 0.28 μg/m3) resulted in significant reductions in the lung lavage concentrations of total cells, neutrophils, and specific proinflammatory cytokines compared with mice pretreated with sterile saline. These results confirm the LPS-inhibitory effect of RsDPLA and support the role of endotoxin as the principal agent in grain dust causing airway inflammation.


2015 ◽  
Vol 309 (5) ◽  
pp. H827-H834 ◽  
Author(s):  
Liping Zhu ◽  
Oscar A. Carretero ◽  
Jiang Xu ◽  
Pamela Harding ◽  
Nithya Ramadurai ◽  
...  

ANG II type 2 receptor (AT2) and ANG I-converting enzyme 2 (ACE2) are important components of the renin-ANG system. Activation of AT2 and ACE2 reportedly counteracts proinflammatory effects of ANG II. However, the possible interaction between AT2 and ACE2 has never been established. We hypothesized that activation of AT2 increases ACE2 activity, thereby preventing TNF-α-stimulated ICAM-1 expression via inhibition of NF-κB signaling. Human coronary artery endothelial cells were pretreated with AT2 antagonist PD123319 (PD) or ACE2 inhibitor DX600 and then stimulated with TNF-α in the presence or absence of AT2 agonist CGP42112 (CGP). We found that AT2 agonist CGP increased both ACE2 protein expression and activity. This effect was blunted by AT2 antagonist PD. ICAM-1 expression was very low in untreated cells but greatly increased by TNF-α. Activation of AT2 with agonist CGP or with ANG II under concomitant AT1 antagonist reduced TNF-α-induced ICAM-1 expression, which was reversed by AT2 antagonist PD or ACE2 inhibitor DX600 or knockdown of ACE2 with small interfering RNA. AT2 activation also suppressed TNF-α-stimulated phosphorylation of inhibitory κB (p-IκB) and NF-κB activity. Inhibition of ACE2 reversed the inhibitory effect of AT2 on TNF-α-stimulated p-IκB and NF-κB activity. Our findings suggest that stimulation of AT2 reduces TNF-α-stimulated ICAM-1 expression, which is partly through ACE2-mediated inhibition of NF-κB signaling.


2015 ◽  
Vol 2015 ◽  
pp. 1-6 ◽  
Author(s):  
Hirayuki Enomoto ◽  
Nobuhiro Aizawa ◽  
Hideji Nakamura ◽  
Ryo Takata ◽  
Yoshiyuki Sakai ◽  
...  

Background. Only a few biomarkers based on metabolic parameters for evaluating liver fibrosis have been reported. The aim of this study was to investigate the relevance of an index obtained from three metabolic variables (glycated albumin: GA, glycated hemoglobin: HbA1c, and branched-chain amino acids to tyrosine ratio: BTR) to the degree of liver fibrosis in hepatitis C virus virus- (HCV-) positive patients.Methods. A total of 394 HCV-positive patients were assessed based on the values of a new index (GA/HbA1c/BTR). The index findings were used to investigate the relationship with the degree of liver fibrosis.Results. The new index showed an association with the stage of fibrosis (METAVIR scores: F0-1: 0.42 ± 0.10, F2: 0.48 ± 0.15, F3: 0.56 ± 0.22, and F4: 0.71 ± 0.30). The index was negatively correlated with three variables of liver function: the prothrombin time percentage (P<0.0001), albumin level (P<0.0001), and cholinesterase level (P<0.0001). The new index showed a higher correlation related to liver function than FIB-4 and the APRI did. In addition, the index showed a higher AUROC value than that of FIB-4 and the APRI for prediction of liver cirrhosis.Conclusion. The new metabolism-related index, GA/HbA1c/BTR value, is shown to relate to the degree of liver fibrosis in HCV-positive patients.


Endocrinology ◽  
2004 ◽  
Vol 145 (11) ◽  
pp. 4806-4812 ◽  
Author(s):  
Mischael Dehoux ◽  
Ronald Van Beneden ◽  
Nevi Pasko ◽  
Pascale Lause ◽  
Josiane Verniers ◽  
...  

Abstract In catabolic conditions, atrogin-1/MAFbx, a muscle-specific ubiquitin-ligase required for muscle atrophy, is increased, and concentrations of IGF-I, a growth factor known to have antiproteolytic action, are reduced. To define the relationship between the decline in IGF-I and the induction of atrogin-1/MAFbx, we studied the effect of IGF-I replacement on atrogin-1/MAFbx mRNA in rats fasted for 51 h and in rats made diabetic with streptozotocin (STZ). Fasting produced a 5.8-fold increase in atrogin-1/MAFbx (P &lt; 0.001). This was attenuated to a 2.5-fold increase by injections of IGF-I (P &lt; 0.05 vs. fasting). Animals with STZ-induced diabetes experienced a 15.1-fold increase in atrogin-1/MAFbx (P &lt; 0.001). Normalization of their circulating IGF-I concentrations by IGF-I infusion blunted the induction of atrogin-1/MAFbx to 6.3-fold (P &lt; 0.05 vs. STZ diabetes without IGF-I). To further delineate the regulation of atrogin-1/MAFbx by IGF-I, we studied a model of cultured muscle cells. We observed that IGF-I produced a time- and dose-dependent reduction of atrogin-1/MAFbx mRNA, with a 50% effective dose of 5 nm IGF-I, a physiological concentration. The degradation rate of atrogin-1/MAFbx mRNA was not affected by IGF-I, suggesting that the reduction of atrogin-1/MAFbx mRNA by IGF-I is a transcriptional effect. Exposure of muscle cells in culture to dexamethasone increased atrogin-1/MAFbx mRNA with a 50% effective dose of 10 nm, a pharmacological concentration. In the presence of dexamethasone, IGF-I at physiological concentrations retained its full inhibitory effect on atrogin-1/MAFbx mRNA. We conclude that IGF-I inhibits atrogin-1/MAFbx expression and speculate that this effect might contribute to the antiproteolytic action of IGF-I in muscle.


Author(s):  
Ghada Araji ◽  
Julian Maamari ◽  
Fatima Ali Ahmad ◽  
Rana Zareef ◽  
Patrick Chaftari ◽  
...  

ABSTRACT The discovery of immune checkpoint inhibitors (ICIs) has revolutionized the care of cancer patients. However, the response to ICI therapy exhibits substantial interindividual variability. Efforts have been directed to identify biomarkers that predict the clinical response to ICIs. In recent years, the gut microbiome has emerged as a critical player that influences the efficacy of immunotherapy. An increasing number of studies have suggested that the baseline composition of a patient's gut microbiota and its dysbiosis are correlated with the outcome of cancer immunotherapy. This review tackles the rapidly growing body of evidence evaluating the relationship between the gut microbiome and the response to ICI therapy. Additionally, this review highlights the impact of antibiotic-induced dysbiosis on ICI efficacy and discusses the possible therapeutic interventions to optimize the gut microbiota composition to augment immunotherapy efficacy.


2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Yan Yang ◽  
Zeyang Lin ◽  
Zhaopu Han ◽  
Zhengxin Wu ◽  
Jianyu Hua ◽  
...  

AbstractColorectal cancer (CRC) is a common tumor that harms human health with a high recurrence rate. It has been reported that the expression of microRNA-539 (miR-539) is low in several types of cancer, including CRC. Tumor necrosis factor (TNF)-α-induced protein 8 (TNFAIP8/TIPE) is highly expressed in CRC and promotes the proliferation, migration and angiogenesis of CRC. However, the relationship between miR-539 and TIPE and the mechanisms by which they regulate the proliferation of CRC remain to be explored. We aimed to investigate the functions and mechanisms of miR-539 in CRC proliferation. Functionally, miR-539 can bind to and regulate the expression of TIPE, and miR-539 activates SAPK/JNK to downregulate the expression of glutathione peroxidase 4 (GPX4) and promote ferroptosis. Our data reveal the novel role of miR-539 in regulating ferroptosis in CRC via activation of the SAPK/JNK axis, providing new insight into the mechanism of abnormal proliferation in CRC and a novel potential therapeutic target for advanced CRC.


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