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Background: Cirrhosis is associated with a proinflammatory environment., Aims: To analyse aetiology-specific inflammation patterns in compensated cirrhosis in animal models and patients., Methods: Portal pressure (PP), fibrosis (collagen proportionate area [CPA]) and hepatic inflammation were measured in cirrhotic rat models (thioacetamide [TAA;n = 12]; choline-deficient high-fat diet [CDHFD;n = 12]; bile duct ligation [BDL;n = 16]). Compensated cirrhotic patients (alcohol-related liver disease [ALD;n = 67]; metabolic dysfunction-associated steatohepatitis [MASH;n = 50]; cholestatic liver disease [primary biliary cholangitis [PBC]/primary sclerosing cholangitis [PSC];n = 22]) undergoing hepatic venous pressure gradient (HVPG) measurement were included., Results: In rats, hepatic proinflammatory gene expression was highest in CDHFD and lowest in TAA, despite comparable PP levels. Across all animal models, Tnfa/Il6 correlated positively with CPA, and Mcp1 with elevated PP. Mcp1 was also associated with increased CPA in TAA/CDHFD. Mcp1/Cxcl1 showed a model-independent positive correlation to transaminases. Il1b correlated positively with CPA/PP in BDL and with transaminases in CDHFD. In patients, CRP/IL-6 were lower in MASH compared to ALD or PBC/PSC, regardless of hepatic function. IgA/IgG were highest and complement factors lowest in ALD. More pronounced systemic inflammation was linked to higher HVPG primarily in ALD/MASH., Conclusion: Proinflammatory pathways are upregulated across all liver disease aetiologies, yet their association with fibrosis and portal hypertension can vary., Competing Interests: Conflict of interest B.S.H., P.K., K.B., O.P., V.T., T.S. and K.Z. declare no conflict of interest. B.S. received travel support from AbbVie and Gilead. G.S. received travel support from Gilead and Amgen. S.G.K. and L.P. are employees of Boehringer Ingelheim. M.T. received grant support from Albireo, Alnylam, Cymabay, Falk, Gilead, Intercept, MSD, Takeda and UltraGenyx, honoraria for consulting from AbbVie, Albireo, Boehringer Ingelheim, BiomX, Falk, Genfit, Gilead, Hightide, Intercept, Jannsen, MSD, Novartis, Phenex, Pliant, Regulus, Siemens and Shire, speaker fees from Albireo, Bristol-Myers Squibb, Falk, Gilead, Intercept, MSD and Madrigal, as well as travel support from AbbVie, Falk, Gilead and Intercept. M.M. served as a speaker and/or consultant and/or advisory board member for AbbVie, Collective Acumen, Gilead, and W. L. Gore & Associates and received travel support from AbbVie and Gilead. P.S. received consulting fees from PharmaIN. T.R. received grant support from AbbVie, Boehringer Ingelheim, Gilead, MSD, Philips Healthcare, Gore; speaking honoraria from AbbVie, Gilead, Gore, Intercept, Roche, MSD; consulting/advisory board fee from AbbVie, Bayer, Boehringer Ingelheim, Gilead, Intercept, MSD, Siemens; as well as travel support from Boehringer Ingelheim, Gilead and Roche., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Persistent liver injury triggers a fibrogenic program that causes pathologic remodeling of the hepatic microenvironment (i.e., liver fibrosis) and portal hypertension. The dynamics of gene regulation during liver disease progression and early regression remain understudied. Here, we generated hepatic transcriptome profiles in two well-established liver disease models at peak fibrosis and during spontaneous regression after the removal of the inducing agents. We linked the dynamics of key disease readouts, such as portal pressure, collagen area, and transaminase levels, to differentially expressed genes, enabling the identification of transcriptomic signatures of progressive vs. regressive liver fibrosis and portal hypertension. These candidate biomarkers (e.g., Tcf4 , Mmp7 , Trem2 , Spp1 , Scube1 , Islr ) were validated in RNA sequencing datasets of patients with cirrhosis and portal hypertension, and those cured from hepatitis C infection. Finally, deconvolution identified major cell types and suggested an association of macrophage and portal hepatocyte signatures with portal hypertension and fibrosis area., Competing Interests: The authors declare no competing interests., (© 2024 The Author(s).)

Non-alcoholic steatohepatitis (NASH) has emerged as a major challenge for public health because of high global prevalence and lack of evidence-based therapies. Most animal models of NASH lack sufficient validation regarding disease progression and pharmacological treatment. The Gubra-Amylin NASH (GAN) diet-induced obese (DIO) mouse demonstrate clinical translatability with respect to disease etiology and hallmarks of NASH. This study aimed to evaluate disease progression and responsiveness to clinically effective interventions in GAN DIO-NASH mice. Disease phenotyping was performed in male C57BL/6J mice fed the GAN diet high in fat, fructose, and cholesterol for 28-88 weeks. GAN DIO-NASH mice with biopsy-confirmed NASH and fibrosis received low-caloric dietary intervention, semaglutide (30 nmol/kg/day, s.c.) or lanifibranor (30 mg/kg/day, p.o.) for 8 and 12 weeks, respectively. Within-subject change in nonalcoholic fatty liver disease (NAFLD) Activity Score (NAS) and fibrosis stage was evaluated using automated deep learning-based image analysis. GAN DIO-NASH mice showed clear and reproducible progression in NASH, fibrosis stage, and tumor burden with high incidence of hepatocellular carcinoma. Consistent with clinical trial outcomes, semaglutide and lanifibranor improved NAS, whereas only lanifibranor induced regression in the fibrosis stage. Dietary intervention also demonstrated substantial benefits on metabolic outcomes and liver histology. Differential therapeutic efficacy of semaglutide, lanifibranor, and dietary intervention was supported by quantitative histology, RNA sequencing, and blood/liver biochemistry. In conclusion, the GAN DIO-NASH mouse model recapitulates various histological stages of NASH and faithfully reproduces histological efficacy profiles of compounds in advanced clinical development for NASH. Collectively, these features highlight the utility of GAN DIO-NASH mice in preclinical drug development., (© 2022 Gubra. Clinical and Translational Science published by Wiley Periodicals LLC on behalf of American Society for Clinical Pharmacology and Therapeutics.)

Background and Aims: Preclinical data suggest that the ageing-induced miR-34a regulates vascular senescence. Herein we sought to assess whether the miR-34 family members miR-34a, miR-34b and miR-34c are involved in human arterial disease., Methods: Expression levels of miR-34a/b/c were quantified by TaqMan assay in peripheral blood mononuclear cells (PBMCs) derived from a consecutive cohort of 221 subjects who underwent cardiovascular risk assessment and thorough vascular examination for aortic stiffness and extent of arterial atherosclerosis., Results: High miR-34a was independently associated with the presence of CAD [OR (95%C.I.): 3.87 (1.56-9.56); p = 0.003] and high miR-34c with the number of diseased arterial beds [OR (95%C.I.): 1.88 (1.034-3.41); p = 0.038], while concurrent high expression of miR-34-a/c or all three miR-34a/b/c was associated with aortic stiffening (miR-34a/c: p = 0.022; miR-34a/b/c: p = 0.041) and with the extent of atherosclerosis [OR (95%C.I.) for number of coronary arteries [miR-34a/c: 3.29 (1.085-9.95); miR-34a/b/c: 6.06 (1.74-21.2)] and number of diseased arterial beds [miR-34a/c: 3.51 (1.45-8.52); miR-34a/b/c: 2.89 (1.05-7.92)] after controlling for possible confounders (p < 0.05 for all). Mechanistically, the increased levels of miR-34a or miR-34c were inversely associated with expression of SIRT1 or JAG1, NOTCH2, CTNNB1 and ATF1, respectively. The association of miR-34a/c or miR-34a/b/c with CAD was mainly mediated through SIRT1 and to a lesser extent through JAG1 as revealed by generalized structural equation modeling. Leukocyte-specific ablation of miR-34a/b/c ameliorates atherosclerotic plaque development and increases Sirt1 and Jag1 expression in an atherosclerosis mouse model confirming the human findings., Conclusions: The present study reveals the clinical significance of the additive role of miR-34a/b/c in vascular ageing and atherosclerotic vascular disease., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Background: The majority of the human genome comprises noncoding sequences, which are in part transcribed as long noncoding RNAs (lncRNAs). lncRNAs exhibit multiple functions, including the epigenetic control of gene expression. In this study, the effect of the lncRNA MALAT1 (metastasis-associated lung adenocarcinoma transcript 1) on atherosclerosis was examined., Methods: The effect of MALAT1 on atherosclerosis was determined in apolipoprotein E-deficient (Apoe - /- ) MALAT1-deficient (Malat1 -/- ) mice that were fed with a high-fat diet and by studying the regulation of MALAT1 in human plaques., Results: Apoe -/- Malat1 -/- mice that were fed a high-fat diet showed increased plaque size and infiltration of inflammatory CD45 + cells compared with Apoe -/- Malat1 +/+ control mice. Bone marrow transplantation of Apoe -/- Malat1 -/- bone marrow cells in Apoe -/- Malat1 +/+ mice enhanced atherosclerotic lesion formation, which suggests that hematopoietic cells mediate the proatherosclerotic phenotype. Indeed, bone marrow cells isolated from Malat1 -/- mice showed increased adhesion to endothelial cells and elevated levels of proinflammatory mediators. Moreover, myeloid cells of Malat1 -/- mice displayed enhanced adhesion to atherosclerotic arteries in vivo. The anti-inflammatory effects of MALAT1 were attributed in part to reduction of the microRNA miR-503. MALAT1 expression was further significantly decreased in human plaques compared with normal arteries and was lower in symptomatic versus asymptomatic patients. Lower levels of MALAT1 in human plaques were associated with a worse prognosis., Conclusions: Reduced levels of MALAT1 augment atherosclerotic lesion formation in mice and are associated with human atherosclerotic disease. The proatherosclerotic effects observed in Malat1 -/- mice were mainly caused by enhanced accumulation of hematopoietic cells.

In vitro models mimicking capillary sprouting are important tools to investigate the tumor angiogenesis, developmental blood vessel formation, and pathophysiological remodeling processes of the capillary system in the adult. With this focus, in 1998 Korff et al. introduced endothelial cell (EC) spheroids as a three-dimensional in vitro model resembling angiogenic responses and sprouting behavior [1]. As such, EC spheroids are capable of giving rise to capillary-like sprouts which are relatively close to the physiologically and genetically programmed arrangement of endothelial cells in vessels. Co-culture spheroids consisting of endothelial cells and smooth muscle cells form a spheroidal core composed of smooth muscle cells and an outer monolayer of endothelial cells, similar to the physiological architecture of larger blood vessels. In practise, a defined number of endothelial cells are cultured in a round-bottom well plate or in "hanging drops" to allow the formation and arrangement of the spheroidal three-dimensional structure. Subsequently, they are harvested and embedded in a collagen gel to allow outgrowth of endothelial cell sprouts originating from each spheroid. To evaluate the pro- or antiangiogenic impact of a cytokine or compound, the number and length of sprouts is determined.

Background: The effectiveness of point of care (POC) right upper quadrant ultrasound (RUQ US) in the diagnosis of biliary disease has been well studied. Extrabiliary pathology that might remain undetected in the course of typical, focused POC RUQ US has not been directly examined., Objectives: Our objective was to determine the prevalence and clinical significance of extrabiliary findings (EBFs) seen on radiology-performed, comprehensive RUQ US., Methods: We conducted a retrospective review of all adult patients undergoing radiology-performed RUQ US in the emergency department (ED) between January 2007 and April 2012. Ultrasound findings and contemporaneous laboratory values were collected. EBFs were identified and further classified by clinical significance., Results: A total of 1579 charts were included, demonstrating a total of 1030 EBFs, with 747 (47.3% [95% confidence interval {CI}, 44.8-49.8%]) patients demonstrating ≥ 1 EBF. Of these EBFs, 184 were classified as clinically significant (CSEBFs) and 150 (9.5% [95% CI, 8.1-11.0%]) patients had ≥ 1 CSEBF. A total of 50 unspecified masses were seen in 47 (3.0% [95% CI, 2.1-3.8%]) patients, with 8 (0.5%) representing a previously undiagnosed malignancy., Conclusion: CSEBFs were seen in < 10% of ED patients undergoing comprehensive RUQ US. Nonspecific masses were seen in 3% of patients, but < 1% of patients were found to have a new malignancy., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Despite the high prevalence of venous diseases that are associated with and based on the structural reorganization of the venous vessel wall, not much is known about their mechanistic causes. In this context, we demonstrated that the quantity of myocardin, a transcriptional regulator of the contractile and quiescent smooth muscle cell phenotype, was diminished in proliferating synthetic venous smooth muscle cells (VSMCs) of human and mouse varicose veins by 51 and 60%, respectively. On the basis of the relevance of proteasomal activity for such phenotypic changes, we hypothesized that the observed VSMC activation is attenuated by the proteasome inhibitor bortezomib. This drug fully abolished VSMC proliferation and loss of myocardin in perfused mouse veins and blocked VSMC invasion in collagen gels by almost 80%. In line with this, topical transdermal treatment with bortezomib diminished VSMC proliferation by 80%, rescued 90% of VSMC myocardin abundance, and inhibited varicose-like venous remodeling by 67 to 72% in a mouse model. Collectively, our data indicate that the proteasome plays a pivotal role in VSMC phenotype changes during venous remodeling processes. Its inhibition protects from varicose-like vein remodeling in mice and may thus serve as a putative therapeutic strategy to treat human varicose veins., (© FASEB.)

Arteriogenesis-the growth of collateral arterioles-partially compensates for the progressive occlusion of large conductance arteries as it may occur as a consequence of coronary, cerebral or peripheral artery disease. Despite being clinically highly relevant, mechanisms driving this process remain elusive. In this context, our study revealed that abundance of regulator of G-protein signalling 5 (RGS5) is increased in vascular smooth muscle cells (SMCs) of remodelling collateral arterioles. RGS5 terminates G-protein-coupled signalling cascades which control contractile responses of SMCs. Consequently, overexpression of RGS5 blunted Gαq/11-mediated mobilization of intracellular calcium, thereby facilitating Gα12/13-mediated RhoA signalling which is crucial for arteriogenesis. Knockdown of RGS5 evoked opposite effects and thus strongly impaired collateral growth as evidenced by a blockade of RhoA activation, SMC proliferation and the inability of these cells to acquire an activated phenotype in RGS5-deficient mice after the onset of arteriogenesis. Collectively, these findings establish RGS5 as a novel determinant of arteriogenesis which shifts G-protein signalling from Gαq/11-mediated calcium-dependent contraction towards Gα12/13-mediated Rho kinase-dependent SMC activation., (© 2014 The Authors. Published under the terms of the CC BY 4.0 license.)

Background: Nuclear factor of activated T-cells 5 (NFAT5) has recently been described to control the phenotype of vascular smooth muscle cells (VSMCs). Although an increase in wall stress or stretch (eg, elicited by hypertension) is a prototypic determinant of VSMC activation, the impact of this biomechanical force on the activity of NFAT5 is unknown. This study intended to reveal the function of NFAT5 and to explore potential signal transduction pathways leading to its activation in stretch-stimulated VSMCs., Methods and Results: Human arterial VSMCs were exposed to biomechanical stretch and subjected to immunofluorescence and protein-biochemical analyses. Stretch promoted the translocation of NFAT5 to the nucleus within 24 hours. While the protein abundance of NFAT5 was regulated through activation of c-Jun N-terminal kinase under these conditions, its translocation required prior activation of palmitoyltransferases. DNA microarray and ChiP analyses identified the matrix molecule tenascin-C as a prominent transcriptional target of NFAT5 under these conditions that stimulates migration of VSMCs. Analyses of isolated mouse femoral arteries exposed to hypertensive perfusion conditions verified that NFAT5 translocation to the nucleus is followed by an increase in tenascin-C abundance in the vessel wall., Conclusions: Collectively, our data suggest that biomechanical stretch is sufficient to activate NFAT5 both in native and cultured VSMCs where it regulates the expression of tenascin-C. This may contribute to an improved migratory activity of VSMCs and thus promote maladaptive vascular remodeling processes such as hypertension-induced arterial stiffening.

The development of varicose veins or chronic venous insufficiency is preceded by and associated with the pathophysiological remodelling of the venous wall. Recent work suggests that an increase in venous filling pressure is sufficient to promote varicose remodelling of veins by augmenting wall stress and activating venous endothelial and smooth muscle cells. In line with this, known risk factors such as prolonged standing or an obesity-induced increase in venous filling pressure may contribute to varicosis. This review focuses on biomechanically mediated mechanisms such as an increase in wall stress caused by venous hypertension or alterations in blood flow, which may be involved in the onset of varicose vein development. Finally, possible therapeutic options to counteract or delay the progress of this venous disease are discussed.

Aims: Hypertension evokes detrimental changes in the arterial vessel wall that facilitate stiffening and thus lead to a further rise in mean blood pressure, eventually causing heart failure. The underlying pathophysiological remodelling process is elicited by an increase in wall stress (WS) and is strictly dependent on the activation of vascular smooth muscle cells (SMC). However, it remains unclear as to why these cells fail to maintain their contractile and quiescent phenotype in a hypertensive environment., Methods and Results: In this context, we reveal that the knockdown of myocardin--a pivotal transcriptional determinant of the contractile SMC phenotype--is sufficient to induce SMC proliferation. In line with this observation, immunofluorescence analysis of the media of remodelling arteries from hypertensive mice demonstrated a significant decrease in the abundance of myocardin and an increase in SMC proliferation. Subsequent analyses of isolated perfused mouse arteries and human cultured SMCs exposed to cyclic stretch (i.e. mimicking one component of WS) suggested that this biomechanical force facilitates serine phosphorylation of myocardin. Furthermore, this biomechanical stimulus promotes rapid translocation of myocardin from the nucleus to the cytoplasm, inhibits its mRNA expression, and causes proteasomal degradation of the cytoplasmic protein., Conclusions: Collectively, these findings suggest that hypertension negates the activity of myocardin in SMCs on multiple levels, hence eliminating a crucial determinant of SMC quiescence. This mechanism may control the initial switch from the contractile towards the synthetic SMC phenotype during hypertension and may offer an interesting novel approach to prevent cardiovascular disease.