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1.
FASEB J ; 36 Suppl 12022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35555429

RESUMO

BACKGROUND & AIM: Cholestatic liver diseases present with ductular reaction, biliary senescence, peribiliary inflammation and bridging fibrosis, and sex-dependent differences in liver injury exist in different pathologies. The multidrug resistance 2 knockout (Mdr2-/- ) mouse is a model of toxic bile-induced cholangitis which show a higher degree of injury in female mice. Estrogen signals through its receptors, ER-α and ER-ß, that form homodimers and act as transcription factors. Interestingly, ER-α and ER-ß can have differing downstream responses. In a model of autoimmune cholestasis, inhibition of ER-ß reduces biliary damage, inflammation, immune cell infiltration and liver fibrosis in both male and female mice. We aimed to determine the role of estrogen/ER-ß signaling on biliary and liver damage in female Mdr2-/- mice. METHODS: Studies were performed in female wild-type (WT) and Mdr2-/- mice at 12 wks of age, with a subset of Mdr2-/- mice subjected to ovariectomy (OVX, to reduce estrogen levels) or treated with PHTPP (ER-ß antagonist, 15 mg/kg BW/day by I.P. implanted minipump) for 1 wk. All studies utilized n=4 mice per group. We evaluated liver damage by H&E staining. Ductular reaction was measured by CK-19 staining and semi-quantification, and biliary senescence was imaged using p16 co-staining with CK-19 (to mark bile ducts). Peribiliary inflammation was evaluated using F4/80 (macrophage marker) staining and semi-quantification, and qPCR for IL-6 and TNF-α in total liver samples. Immune cell infiltration was visualized by staining for CD3 (pan-T cell marker) and CD20 (pan-B cell marker). We determined liver fibrosis by (i) Sirius red staining and semi-quantification, (ii) qPCR for TIMP1, Col1a1 and αSMA in total liver samples and (iii) co-staining for desmin (hepatic stellate cell marker) with CK-19. Human female control (avg. age 24.5 yr) and late-stage, untreated PSC patient (avg. age 51.8 yr) serum samples were evaluated for estrogen levels by EIA. RESULTS: OVX exacerbated liver damage, ductular reaction, biliary senescence, inflammation, immune response and liver fibrosis in female Mdr2-/- mice, demonstrating a protective effect of estrogen signaling during cholangitis. Interestingly, female Mdr2-/- mice treated with PHTPP (blocks ER-ß activity) had no change in any parameters of biliary damage or liver injury when compared to controls suggesting that estrogen's protective effects are not mediated through ER-ß. Serum estrogen levels increased in female PSC samples versus control, potentially as a compensatory response or abnormal dysregulation as a consequence of injury. CONCLUSION: Estrogen may have a protective effect against biliary damage, inflammation, immune response and liver fibrosis during cholestasis. However, the protective effects are not dependent upon ER-ß signaling in female Mdr2-/- mice and future work is ongoing to understand the role or ER-α in this setting. Alteration of specific estrogen signaling mechanisms may be important for targeting cholestatic liver diseases in female patients.

2.
FASEB J ; 36 Suppl 12022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35557100

RESUMO

BACKGROUND: Neuropeptides modulate the pathogenesis of primary sclerosing cholangitis (PSC) by affecting i) biliary senescence/ductular reaction (DR), and ii) liver inflammation and fibrosis. Damaged cholangiocytes develop a neuroendocrine phenotype and respond to neurokinin 1 (NK1, i.e. substance P [SP]) signaling via NK1 receptor (NK1R). SP serum levels increase in PSC patients and depletion of NK1R in Mdr2-/- mice (NK1R/Mdr2 double knockout (DKO)) ameliorates DR and fibrosis compared to Mdr2-/- mice. Mast cells (MCs) (i) respond to sensory neuropeptide signaling; (ii) infiltrate the liver following injury; (iii) reside near bile ducts and (iv) promote PSC phenotypes in Mdr2-/- mice, and injection of MCs into WT mice increases DR, inflammation and hepatic fibrosis. We hypothesize that MCs contribute to DR and liver fibrosis via SP/NK1R signaling in cholestasis. METHODS: Male WT, NK1R-/- , Mdr2-/- and DKO mice at 12 wks were used. NK1R-/- and DKO mice received a single tail vein injection of cultured, tagged murine MCs (ATCC MC/9, 105 cells/injection) or saline. Liver damage was evaluated by H&E staining. MC presence was confirmed by tryptase ß2 immunohistochemistry (IHC). MC activation was determined by serum histamine (HA) levels using enzyme-linked immunoassay (EIA). DR was measured by cytokeratin-19 (CK-19) IHC and biliary senescence by co-immunofluorescence (co-IF) for p16/CK-19. Inflammation was measured by F4/80 IHC and hepatic fibrosis by Sirius Red staining. Serum SP levels were measured by EIA. αSMA immunoreactivity was measured by co-IF with CK-19 in liver sections. Ingenuity Pathway Analysis (IPA) showed that SP modulates TGF-ß1 expression; therefore, serum TGF-ß1 levels were measured by EIA. In vitro, primary cholangiocytes from PSC patients were treated with an NK1R antagonist, Aprepitant (10 µM, 24 hrs) or vehicle in the bottom of Boyden chambers. MCs were added to the upper chamber and MC migration was evaluated by toluidine blue staining. RESULTS: Injected MCs localized in peribiliary regions of NK1R-/- and DKO mice and increased hepatic damage, DR, biliary senescence, inflammation and fibrosis in both NK1R-/- and DKO mice compared to their respective controls and WT. Serum HA and SP levels were reduced in NK1R-/- and DKO mice compared to Mdr2-/- mice, which increased following MC injection. Serum TGF-ß1 levels were reduced in NK1R-/- and DKO mice compared to Mdr2-/- and increased following MC injection. By Pearson's correlation analysis, serum TGF-ß1 positively correlated with HA in all groups. In vitro, NK1R antagonist treatment reduced MC migration towards isolated PSC cholangiocytes compared to control. CONCLUSION: MCs contribute to hepatic SP/NK1R signaling, biliary damage and peribiliary fibrosis via TGF-ß1 signaling. MC activation of NK1R signaling is critical for MC-mediated damage in PSC.

3.
FASEB J ; 36 Suppl 12022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35557275

RESUMO

BACKGROUND & AIM: Primary Sclerosing Cholangitis (PSC) is a cholestatic liver disease characterized by hepatic fibrosis and portal inflammation. Melatonin is synthesized by arylalkylamine N-acetyltransferase (AANAT) in the pineal gland, as well as extrapineal sites such as cholangiocytes. We previously found that: (i) the MT1 receptor is primarily expressed in cholangiocytes with low and absent expression in hepatic stellate cells and hepatocytes, respectively; (ii) melatonin reduces biliary proliferation via MT1 receptor signaling; and (iii) melatonin treatment for 1 wk decreases biliary proliferation and liver fibrosis in bile duct ligated rats by downregulation of MT1 and clock genes (PER1, CRY1, CLOCK and BMAL1). We aimed to evaluate the beneficial effects of long-term melatonin treatment and MT1 signaling on biliary phenotypes, liver fibrosis and portal inflammation in Mdr2-/- mice (a model of PSC). METHODS: Male FVB/NJ and Mdr2-/- mice had access ad libitum to drinking water with/without melatonin for 3 months. We evaluated: (i) ductular reaction (DR) by immunohistochemistry (IHC) for CK19, (ii) liver fibrosis by Sirius Red staining and (iii) portal inflammation by IHC for F4/80. MT1, AANAT, and clock genes immunoreactivity was evaluated by immunofluorescence (IF) co-stained with CK19 and qPCR in isolated cholangiocytes. Male C3H-Hej (WT for MT1-/- ), FVB/NJ (WT for Mdr2-/- ), MT1-/- , Mdr2-/- mice and MT1-/- /Mdr2-/- (DKO) mice were euthanized at 12 wk of age. We analyzed: (i) MT1 expression by IF and mRNA expression in total liver by qPCR to validate our model; (ii) liver damage by H&E, DR by IHC for CK19 and liver fibrosis by Sirius Red staining and (iii) portal inflammation by IHC for F4/80 and expression of the inflammatory markers by qPCR in total liver. RESULTS: Long-term melatonin treatment reduces DR, liver fibrosis and portal inflammation in Mdr2-/- mice. Prolonged administration of melatonin in Mdr2-/- mice improves liver phenotype by decreasing the immunoreactivity of MT1, AANAT and clock genes in Mdr2-/- mice, which suggests the chronobiotic action of melatonin on biliary circadian rhythm. DKO mice have no MT1 expression and display ameliorated liver phenotype compared to Mdr2-/- mice. CONCLUSION: We demonstrated that chronic melatonin treatment improves liver histology and restores the biliary circadian rhythm by interaction with MT1. Suppression of MT1 receptor in Mdr2-/- mice ameliorates biliary/liver phenotypes through changes in clock genes and AANAT. Restoration of the circadian rhythm by modulation of melatonin/MT1 signaling may be key for the management of cholangiopathies.

4.
Cells ; 11(9)2022 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-35563897

RESUMO

BACKGROUND & AIMS: Cholangiocytes are the target cells of liver diseases that are characterized by biliary senescence (evidenced by enhanced levels of senescence-associated secretory phenotype, SASP, e.g., TGF-ß1), and liver inflammation and fibrosis accompanied by altered bile acid (BA) homeostasis. Taurocholic acid (TC) stimulates biliary hyperplasia by activation of 3',5'-cyclic cyclic adenosine monophosphate (cAMP) signaling, thereby preventing biliary damage (caused by cholinergic/adrenergic denervation) through enhanced liver angiogenesis. Also: (i) α-calcitonin gene-related peptide (α-CGRP, which activates the calcitonin receptor-like receptor, CRLR), stimulates biliary proliferation/senescence and liver fibrosis by enhanced biliary secretion of SASPs; and (ii) knock-out of α-CGRP reduces these phenotypes by decreased cAMP levels in cholestatic models. We aimed to demonstrate that TC effects on liver phenotypes are dependent on changes in the α-CGRP/CALCRL/cAMP/PKA/ERK1/2/TGF-ß1/VEGF axis. METHODS: Wild-type and α-CGRP-/- mice were fed with a control (BAC) or TC diet for 1 or 2 wk. We measured: (i) CGRP levels by both ELISA kits in serum and by qPCR in isolated cholangiocytes (CALCA gene for α-CGRP); (ii) CALCRL immunoreactivity by immunohistochemistry (IHC) in liver sections; (iii) liver histology, intrahepatic biliary mass, biliary senescence (by ß-GAL staining and double immunofluorescence (IF) for p16/CK19), and liver fibrosis (by Red Sirius staining and double IF for collagen/CK19 in liver sections), as well as by qPCR for senescence markers in isolated cholangiocytes; and (iv) phosphorylation of PKA/ERK1/2, immunoreactivity of TGF-ß1/TGF- ßRI and angiogenic factors by IHC/immunofluorescence in liver sections and qPCR in isolated cholangiocytes. We measured changes in BA composition in total liver by liquid chromatography/mass spectrometry. RESULTS: TC feeding increased CALCA expression, biliary damage, and liver inflammation and fibrosis, as well as phenotypes that were associated with enhanced immunoreactivity of the PKA/ERK1/2/TGF-ß1/TGF-ßRI/VEGF axis compared to BAC-fed mice and phenotypes that were reversed in α-CGRP-/- mice fed TC coupled with changes in hepatic BA composition. CONCLUSION: Modulation of the TC/ α-CGRP/CALCRL/PKA/ERK1/2/TGF-ß1/VEGF axis may be important in the management of cholangiopathies characterized by BA accumulation.

7.
Cancers (Basel) ; 14(6)2022 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-35326593

RESUMO

The poor prognosis of cholangiocarcinoma in humans is related to several factors, such as (i) the heterogeneity of the disease, (ii) the late onset of symptoms and (iii) the limited comprehension of the carcinogenic pathways determining neoplastic changes, which all limit the pursuit of appropriate treatment. Several risk factors have been recognized, including different infective, immune-mediated, and dysmorphogenic disorders of the biliary tree. In this review, we report the details of possible mechanisms that lead a specific premalignant pathological condition to become cholangiocarcinoma. For instance, during liver fluke infection, factors secreted from the worms may play a major role in pathogenesis. In primary sclerosing cholangitis, deregulation of histamine and bile-acid signaling may determine important changes in cellular pathways. The study of these molecular events may also shed some light on the pathogenesis of sporadic (unrelated to risk factors) forms of cholangiocarcinoma, which represent the majority (nearly 75%) of cases.

8.
Hepatol Commun ; 2022 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-35271760

RESUMO

Fibroblast growth factor 1 (FGF1) belongs to a family of growth factors involved in cellular growth and division. MicroRNA 16 (miR-16) is a regulator of gene expression, which is dysregulated during liver injury and insult. However, the role of FGF1 in the progression of biliary proliferation, senescence, fibrosis, inflammation, angiogenesis, and its potential interaction with miR-16, are unknown. In vivo studies were performed in male bile duct-ligated (BDL, 12-week-old) mice, multidrug resistance 2 knockout (Mdr2-/-) mice (10-week-old), and their corresponding controls, treated with recombinant human FGF1 (rhFGF1), fibroblast growth factor receptor (FGFR) antagonist (AZD4547), or anti-FGF1 monoclonal antibody (mAb). In vitro, the human cholangiocyte cell line (H69) and human hepatic stellate cells (HSCs) were used to determine the expression of proliferation, fibrosis, angiogenesis, and inflammatory genes following rhFGF1 treatment. PSC patient and control livers were used to evaluate FGF1 and miR-16 expression. Intrahepatic bile duct mass (IBDM), along with hepatic fibrosis and inflammation, increased in BDL mice treated with rhFGF1, with a corresponding decrease in miR-16, while treatment with AZD4547 or anti-FGF1 mAb decreased hepatic fibrosis, IBDM, and inflammation in BDL and Mdr2-/- mice. In vitro, H69 and HSCs treated with rhFGF1 had increased expression of proliferation, fibrosis, and inflammatory markers. PSC samples also showed increased FGF1 and FGFRs with corresponding decreases in miR-16 compared with healthy controls. Conclusion: Our study demonstrates that suppression of FGF1 and miR-16 signaling decreases the presence of hepatic fibrosis, biliary proliferation, inflammation, senescence, and angiogenesis. Targeting the FGF1 and miR-16 axis may provide therapeutic options in treating cholangiopathies such as PSC.

9.
Am J Pathol ; 2022 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-35337836

RESUMO

Primary liver cancer includes hepatocellular carcinoma (HCC) and cholangiocarcinoma (CCA). Incidence of liver cancer has been increasing in recent years, and the 5-year survival is still <20%. HCC and CCA are often accompanied with a dense stroma coupled with infiltrated immune cells, which is referred to as the tumor microenvironment. Populations of specific immune cells, such as high density of CD163+ macrophages and low density of CD8+ T cells, are associated with prognosis and survival rates in both HCC and CCA. Immune cells in the tumor microenvironment can be a therapeutic target for liver cancer treatments. Previous studies have introduced immunotherapy using immune checkpoint inhibitors, pulsed dendritic cells, or transduced T cells, to enhance cytotoxicity of immune cells and inhibit tumor growth. This review summarizes current understanding of the roles of immune cells in primary liver cancer covering HCC and CCA.

13.
Hepatology ; 75(4): 797-813, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34743371

RESUMO

BACKGROUND AND AIMS: Melatonin reduces biliary damage and liver fibrosis in cholestatic models by interaction with melatonin receptors 1A (MT1) and 1B (MT2). MT1 and MT2 can form heterodimers and homodimers, but MT1 and MT2 can heterodimerize with the orphan receptor G protein-coupled receptor 50 (GPR50). MT1/GPR50 dimerization blocks melatonin binding, but MT2/GPR50 dimerization does not affect melatonin binding. GPR50 can dimerize with TGFß receptor type I (TGFßRI) to activate this receptor. We aimed to determine the differential roles of MT1 and MT2 during cholestasis. APPROACH AND RESULTS: Wild-type (WT), MT1 knockout (KO), MT2KO, and MT1/MT2 double KO (DKO) mice underwent sham or bile duct ligation (BDL); these mice were also treated with melatonin. BDL WT and multidrug resistance 2 KO (Mdr2-/- ) mice received mismatch, MT1, or MT2 Vivo-Morpholino. Biliary expression of MT1 and GPR50 increases in cholestatic rodents and human primary sclerosing cholangitis (PSC) samples. Loss of MT1 in BDL and Mdr2-/- mice ameliorated biliary and liver damage, whereas these parameters were enhanced following loss of MT2 and in DKO mice. Interestingly, melatonin treatment alleviated BDL-induced biliary and liver injury in BDL WT and BDL MT2KO mice but not in BDL MT1KO or BDL DKO mice, demonstrating melatonin's interaction with MT1. Loss of MT2 or DKO mice exhibited enhanced GPR50/TGFßR1 signaling, which was reduced by loss of MT1. CONCLUSIONS: Melatonin ameliorates liver phenotypes through MT1, whereas down-regulation of MT2 promotes liver damage through GPR50/TGFßR1 activation. Blocking GPR50/TGFßR1 binding through modulation of melatonin signaling may be a therapeutic approach for PSC.


Assuntos
Colestase , Melatonina , Animais , Colestase/complicações , Colestase/tratamento farmacológico , Cirrose Hepática/tratamento farmacológico , Cirrose Hepática/etiologia , Melatonina/metabolismo , Melatonina/farmacologia , Melatonina/uso terapêutico , Camundongos , Camundongos Knockout , Receptor MT1 de Melatonina/genética , Receptor MT1 de Melatonina/metabolismo , Receptor MT2 de Melatonina/genética , Receptor MT2 de Melatonina/metabolismo
15.
Cells ; 10(8)2021 08 12.
Artigo em Inglês | MEDLINE | ID: mdl-34440841

RESUMO

Fatty liver diseases, such as non-alcoholic fatty liver disease (NAFLD), are global health disparities, particularly in the United States, as a result of cultural eating habits and lifestyle. Pathological studies on NAFLD have been mostly focused on hepatocytes and other inflammatory cell types; however, the impact of other biliary epithelial cells (i.e., cholangiocytes) in the promotion of NAFLD is growing. This review article will discuss how cholestatic injury and cholangiocyte activity/ductular reaction influence NAFLD progression. Furthermore, this review will provide informative details regarding the fundamental properties of cholangiocytes and bile acid signaling that can influence NAFLD. Lastly, studies relating to the pathogenesis of NAFLD, cholangiopathies, and ductular reaction will be analyzed to help gain insight for potential therapies.


Assuntos
Ductos Biliares/metabolismo , Colestase/patologia , Hepatopatia Gordurosa não Alcoólica/patologia , Transdução de Sinais , Ácidos e Sais Biliares/metabolismo , Ductos Biliares/citologia , Canabinoides/metabolismo , Colestase/etiologia , Células Epiteliais/citologia , Células Epiteliais/metabolismo , Humanos , Sistemas Neurossecretores/metabolismo , Hepatopatia Gordurosa não Alcoólica/complicações , Fator A de Crescimento do Endotélio Vascular/metabolismo
16.
Cells ; 10(7)2021 07 04.
Artigo em Inglês | MEDLINE | ID: mdl-34359861

RESUMO

Cholangiocarcinoma is a lethal disease with scarce response to current systemic therapy. The rare occurrence and large heterogeneity of this cancer, together with poor knowledge of its molecular mechanisms, are elements contributing to the difficulties in finding an appropriate cure. Cholangiocytes (and their cellular precursors) are considered the liver component giving rise to cholangiocarcinoma. These cells respond to several hormones, neuropeptides and molecular stimuli employing the cAMP/PKA system for the translation of messages in the intracellular space. For instance, in physiological conditions, stimulation of the secretin receptor determines an increase of intracellular levels of cAMP, thus activating a series of molecular events, finally determining in bicarbonate-enriched choleresis. However, activation of the same receptor during cholangiocytes' injury promotes cellular growth again, using cAMP as the second messenger. Since several scientific pieces of evidence link cAMP signaling system to cholangiocytes' proliferation, the possible changes of this pathway during cancer growth also seem relevant. In this review, we summarize the current findings regarding the cAMP pathway and its role in biliary normal and neoplastic cell proliferation. Perspectives for targeting the cAMP machinery in cholangiocarcinoma therapy are also discussed.


Assuntos
Neoplasias dos Ductos Biliares/tratamento farmacológico , Neoplasias dos Ductos Biliares/patologia , Sistema Biliar/patologia , Colangiocarcinoma/tratamento farmacológico , Colangiocarcinoma/patologia , AMP Cíclico/metabolismo , Terapia de Alvo Molecular , Transdução de Sinais , Animais , Proliferação de Células , Humanos
17.
Hepatol Commun ; 5(7): 1125-1137, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34278165

RESUMO

The aging process is represented by the time-dependent decay in physiologic functions of living beings. Major interest has been focused in recent years on the determinants of this progressive condition due to its correlative relationship with the onset of diseases. Several hallmark features have been observed in aging, such as genetic alterations, mitochondrial impairment, and telomere shortening. At the cellular level, a senescent phenotype has been identified in response to aging that is characterized by a flat appearance, proliferative arrest, and production of specific molecules. The net effect of these cells in the course of diseases is an argument of debate. In fact, while the onset of a senescent phenotype may prevent tumor spreading, these cells appear to support pathological processes in some conditions. Several studies are now focused on clarifying the specific molecular pathways of aging/senescence in different cells, tissues, or organs. Biliary and vascular components, within the liver, have emerged as important determinants of some form of liver disease. In this review we summarize the most recent achievements on aging/senescence, focusing on the biliary and vascular liver system. Conclusion: Several findings, in both preclinical animal models and on human liver specimens, converge in supporting the presence of specific aging hallmarks in the diseases involving these hepatic compartments.

18.
Cancers (Basel) ; 13(13)2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34282753

RESUMO

Cholangiocarcinoma (CCA) is a type of biliary tract cancer emerging from the biliary tree. CCA is the second most common primary liver cancer after hepatocellular carcinoma and is highly aggressive resulting in poor prognosis and patient survival. Treatment options for CCA patients are limited since early diagnosis is challenging, and the efficacy of chemotherapy or radiotherapy is also limited because CCA is a heterogeneous malignancy. Basic research is important for CCA to establish novel diagnostic testing and more effective therapies. Previous studies have introduced new techniques and methodologies for animal models, in vitro models, and biomarkers. Recent experimental strategies include patient-derived xenograft, syngeneic mouse models, and CCA organoids to mimic heterogeneous CCA characteristics of each patient or three-dimensional cellular architecture in vitro. Recent studies have identified various novel CCA biomarkers, especially non-coding RNAs that were associated with poor prognosis or metastases in CCA patients. This review summarizes current advances and limitations in basic and translational studies of CCA.

19.
Hepatology ; 74(5): 2684-2698, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34164827

RESUMO

BACKGROUND AND AIMS: Cholestasis is characterized by increased total bile acid (TBA) levels, which are regulated by farnesoid X receptor (FXR)/FGF15. Patients with primary sclerosing cholangitis (PSC) typically present with inflammatory bowel disease (IBD). Mast cells (MCs) (i) express FXR and (ii) infiltrate the liver during cholestasis promoting liver fibrosis. In bile-duct-ligated (BDL) MC-deficient mice (B6.Cg-KitW-sh /HNihrJaeBsmJ [KitW-sh ]), ductular reaction (DR) and liver fibrosis decrease compared with BDL wild type, and MC injection exacerbates liver damage in normal mice. APPROACH AND RESULTS: In this study, we demonstrated that MC-FXR regulates biliary FXR/FGF15, DR, and hepatic fibrosis and alters intestinal FXR/FGF15. We found increased MC number and biliary FXR expression in patients with liver injury compared with control. Histamine and FGF19 serum levels and small heterodimer partner expression increase in patients PSC and PSC-IBD compared with healthy controls. MC injection increased liver damage, DR, inflammation, biliary senescence/senescence-associated secretory phenotype (SASP), fibrosis, and histamine in KitW-sh mice. Inhibition of MC-FXR before injection reduced these parameters. BDL and KitW-sh mice injected with MCs displayed increased TBA content, biliary FXR/FGF15, and intestinal inflammation, which decreased in BDL KitW-sh and KitW-sh mice injected with MC-FXR. MCs increased ileal FXR/FGF15 expression in KitW-sh mice that was reduced following FXR inhibition. BDL and multidrug resistance 2/ATP-binding cassette family 2 member 4 knockout (Mdr2-/- ) mice, models of PSC, displayed increased intestinal MC infiltration and FXR/FGF15 expression. These were reduced following MC stabilization with cromolyn sodium in Mdr2-/- mice. In vitro, MC-FXR inhibition decreased biliary proliferation/SASP/FGF and hepatic stellate cell activation. CONCLUSIONS: Our studies demonstrate that MC-FXR plays a key role in liver damage and DR, including TBA regulation through alteration of intestinal and biliary FXR/FGF15 signaling.


Assuntos
Colangite Esclerosante/complicações , Colestase/imunologia , Doenças Inflamatórias Intestinais/imunologia , Mastócitos/imunologia , Receptores Citoplasmáticos e Nucleares/metabolismo , Animais , Ductos Biliares/imunologia , Ductos Biliares/patologia , Colangite Esclerosante/imunologia , Colangite Esclerosante/patologia , Colestase/patologia , Modelos Animais de Doenças , Fatores de Crescimento de Fibroblastos/metabolismo , Humanos , Masculino , Mastócitos/metabolismo , Camundongos
20.
Hepatology ; 74(4): 1845-1863, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-33928675

RESUMO

BACKGROUND AND AIMS: Human NAFLD is characterized at early stages by hepatic steatosis, which may progress to NASH when the liver displays microvesicular steatosis, lobular inflammation, and pericellular fibrosis. The secretin (SCT)/secretin receptor (SCTR) axis promotes biliary senescence and liver fibrosis in cholestatic models through down-regulation of miR-125b signaling. We aim to evaluate the effect of disrupting biliary SCT/SCTR/miR-125b signaling on hepatic steatosis, biliary senescence, and liver fibrosis in NAFLD/NASH. APPROACH AND RESULTS: In vivo, 4-week-old male wild-type, Sct-/- and Sctr-/- mice were fed a control diet or high-fat diet (HFD) for 16 weeks. The expression of SCT/SCTR/miR-125b axis was measured in human NAFLD/NASH liver samples and HFD mouse livers by immunohistochemistry and quantitative PCR. Biliary/hepatocyte senescence, ductular reaction, and liver angiogenesis were evaluated in mouse liver and human NAFLD/NASH liver samples. miR-125b target lipogenesis genes in hepatocytes were screened and validated by custom RT2 Profiler PCR array and luciferase assay. Biliary SCT/SCTR expression was increased in human NAFLD/NASH samples and in livers of HFD mice, whereas the expression of miR-125b was decreased. Biliary/hepatocyte senescence, ductular reaction, and liver angiogenesis were observed in human NAFLD/NASH samples as well as HFD mice, which were decreased in Sct-/- and Sctr-/- HFD mice. Elovl1 is a lipogenesis gene targeted by miR-125b, and its expression was also decreased in HFD mouse hepatocytes following Sct or Sctr knockout. Bile acid profile in fecal samples have the greatest changes between wild-type mice and Sct-/- /Sctr-/- mice. CONCLUSION: The biliary SCT/SCTR/miR-125b axis promotes liver steatosis by up-regulating lipid biosynthesis gene Elovl1. Targeting the biliary SCT/SCTR/miR-125b axis may be key for ameliorating phenotypes of human NAFLD/NASH.


Assuntos
Hepatopatia Gordurosa não Alcoólica/genética , Receptores Acoplados a Proteínas G/genética , Receptores dos Hormônios Gastrointestinais/genética , Secretina/genética , Animais , Ductos Biliares/citologia , Ductos Biliares/metabolismo , Linhagem Celular , Senescência Celular/genética , Modelos Animais de Doenças , Elongases de Ácidos Graxos/genética , Elongases de Ácidos Graxos/metabolismo , Ácidos Graxos não Esterificados , Hepatócitos/metabolismo , Humanos , Lipogênese/genética , Camundongos , Camundongos Knockout , MicroRNAs/genética , MicroRNAs/metabolismo , Hepatopatia Gordurosa não Alcoólica/metabolismo , Fenótipo , Receptores Acoplados a Proteínas G/metabolismo , Receptores dos Hormônios Gastrointestinais/metabolismo , Secretina/metabolismo , Regulação para Cima
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