Publications by authors named "SL Friedman"

The peptide hormone kisspeptin attenuates liver steatosis, metabolic dysfunction-associated steatohepatitis (MASH), and fibrosis in mouse models by signaling via the kisspeptin 1 receptor (KISS1R). However, whether kisspeptin impacts fibrogenesis in the human liver is not known. We investigated the impact of a potent kisspeptin analog (KPA) on fibrogenesis using human precision-cut liver slices (hPCLS) from fibrotic livers from male patients, in human hepatic stellate cells (HSCs), LX-2, and in primary mouse HSCs.

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Objectives: Hepatic CEACAM1 expression declines with advanced hepatic fibrosis stage in patients with metabolic dysfunction-associated steatohepatitis (MASH). Global and hepatocyte-specific deletions of Ceacam1 impair insulin clearance to cause hepatic insulin resistance and steatosis. They also cause hepatic inflammation and fibrosis, a condition characterized by excessive collagen production from activated hepatic stellate cells (HSCs).

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The worldwide epidemic of steatotic (fatty) liver disease also affects children and adolescents. The consensus statement by Zhang et al. summarizes key evidence on detection, risk factors, manifestations, comorbidities, and potential treatments in children and adolescents.

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Article Synopsis
  • The study aimed to compare traditional pathology methods with a new digital image analysis technique to assess the antifibrotic effects of Aramchol, a drug for metabolic liver disease.
  • In a trial with 51 patients, Aramchol treatment showed varying degrees of fibrosis improvement based on different assessment methods, with 31% of patients showing improvement according to conventional metrics, while digital analysis indicated a 74.5% reduction in fibrosis at least modestly.
  • Results also revealed that longer treatment duration led to greater fibrosis improvement, suggesting that digital image analysis provides a more sensitive measure of treatment effects than traditional methods.
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Metabolic dysfunction-associated steatotic liver disease (MASLD), previously known as non-alcoholic fatty liver disease, encompasses steatosis and metabolic dysfunction-associated steatohepatitis (MASH), leading to cirrhosis and hepatocellular carcinoma. Preclinical MASLD research is mainly performed in rodents; however, the model that best recapitulates human disease is yet to be defined. We conducted a wide-ranging retrospective review (metabolic phenotype, liver histopathology, transcriptome benchmarked against humans) of murine models (mostly male) and ranked them using an unbiased MASLD 'human proximity score' to define their metabolic relevance and ability to induce MASH-fibrosis.

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[Correction Notice: An Erratum for this article was reported online in on Jul 15 2024 (see record 2025-04658-001). In the article, three sentences and a reference were redacted related to proceedings against a university concerning its psychology program because appropriate context was not provided in the article. All versions of this article have been corrected.

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Objectives: Hepatic CEACAM1 expression declines with advanced hepatic fibrosis stage in patients with MASH. Global and hepatocyte-specific deletions of impair insulin clearance to cause hepatic insulin resistance and steatosis. They also cause hepatic inflammation and fibrosis, a condition characterized by excessive collagen production from activated hepatic stellate cells (HSCs).

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Background & Aims: Hepatic stellate cells (HSCs) are the key drivers of fibrosis in metabolic dysfunction-associated steatohepatitis (MASH), the fastest growing cause of hepatocellular carcinoma (HCC) worldwide. HSCs are heterogenous, and a senescent subset of HSCs is implicated in hepatic fibrosis and HCC. Administration of anti-uPAR (urokinase-type plasminogen activator receptor) CAR T cells has been shown to deplete senescent HSCs and attenuate fibrosis in murine models.

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The hepatic content of amyloid beta (Aβ) decreases drastically in human and rodent cirrhosis highlighting the importance of understanding the consequences of Aβ deficiency in the liver. This is especially relevant in view of recent advances in anti-Aβ therapies for Alzheimer's disease (AD). Here, it is shown that partial hepatic loss of Aβ in transgenic AD mice immunized with Aβ antibody 3D6 and its absence in amyloid precursor protein (APP) knockout mice (APP-KO), as well as in human liver spheroids with APP knockdown upregulates classical hallmarks of fibrosis, smooth muscle alpha-actin, and collagen type I.

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Background And Aims: Sustained inflammation and hepatocyte injury in chronic liver disease activate HSCs to transdifferentiate into fibrogenic, contractile myofibroblasts. We investigated the role of protocadherin 7 (PCDH7), a cadherin family member not previously characterized in the liver, whose expression is restricted to HSCs.

Approach And Results: We created a PCDH7 fl/fl mouse line, which was crossed to lecithin retinol acyltransferase-Cre mice to generate HSC-specific PCDH7 knockout animals.

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Metabolic dysfunction-associated steatohepatitis (MASH) can progress to cirrhosis and liver cancer. There are no approved medical therapies to prevent or reverse disease progression. Fructose and its metabolism in the liver play integral roles in MASH pathogenesis and progression.

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Metabolic dysfunction-associated steatotic (fatty) liver disease (MASLD), previously termed non-alcoholic fatty liver disease, is a worldwide epidemic that can lead to hepatic inflammation, fibrosis, cirrhosis, and hepatocellular carcinoma (HCC). The disease is typically a component of the metabolic syndrome that accompanies obesity, and is often overlooked because the liver manifestations are clinically silent until late-stage disease is present (i.e.

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Clinical studies suggest that non-alcoholic steatohepatitis (NASH) is an independent risk factor for chronic kidney disease (CKD), but causality and mechanisms linking these two major diseases are lacking. To assess whether NASH can induce CKD, we have characterized kidney function, histological features, transcriptomic and lipidomic profiles in a well-validated murine NASH model. Mice with NASH progressively developed significant podocyte foot process effacement, proteinuria, glomerulosclerosis, tubular epithelial cell injury, lipid accumulation, and interstitial fibrosis.

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The worldwide prevalence of non-alcoholic steatohepatitis (NASH) is increasing, causing a significant medical burden, but no approved therapeutics are currently available. NASH drug development requires histological analysis of liver biopsies by expert pathologists for trial enrolment and efficacy assessment, which can be hindered by multiple issues including sample heterogeneity, inter-reader and intra-reader variability, and ordinal scoring systems. Consequently, there is a high unmet need for accurate, reproducible, quantitative, and automated methods to assist pathologists with histological analysis to improve the precision around treatment and efficacy assessment.

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Background: Nonalcoholic fatty liver disease (NAFLD) is a disease characterized by lipid accumulation within hepatocytes, ranging from simple steatosis to steatohepatitis, in the absence of secondary causes of hepatic fat accumulation. Although air pollution (AP) has been associated with several conditions related to NAFLD (e.g.

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Metabolic dysfunction-associated steatohepatitis (MASH) is a severe form of liver disease that poses a global health threat because of its potential to progress to advanced fibrosis, leading to cirrhosis and liver cancer. Recent advances in single-cell methodologies, refined disease models, and genetic and epigenetic insights have provided a nuanced understanding of MASH fibrogenesis, with substantial cellular heterogeneity in MASH livers providing potentially targetable cell-cell interactions and behavior. Unlike fibrogenesis, mechanisms underlying fibrosis regression in MASH are still inadequately understood, although antifibrotic targets have been recently identified.

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Hepatic fibrosis is the primary determinant of mortality in patients with metabolic dysfunction-associated steatohepatitis (MASH). Transforming growth factor-β (TGFβ), a master profibrogenic cytokine, is a promising therapeutic target that has not yet been translated into an effective therapy in part because of liabilities associated with systemic TGFβ antagonism. We have identified that soluble folate receptor γ (FOLR3), which is expressed in humans but not in rodents, is a secreted protein that is elevated in the livers of patients with MASH but not in those with metabolic dysfunction-associated steatotic liver disease, those with type II diabetes, or healthy individuals.

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Liver fibrosis is a substantial risk factor for the development and progression of liver cancer, which includes hepatocellular carcinoma (HCC) and intrahepatic cholangiocarcinoma (iCCA). Studies utilizing cell fate mapping and single-cell transcriptomics techniques have identified quiescent perisinusoidal hepatic stellate cells (HSCs) as the primary source of activated collagen-producing HSCs and liver cancer-associated fibroblasts (CAFs) in HCC and liver metastasis, complemented in iCCA by contributions from portal fibroblasts. At the same time, integrative computational analysis of single-cell, single-nucleus and spatial RNA sequencing data have revealed marked heterogeneity among HSCs and CAFs, with distinct subpopulations displaying unique gene expression signatures and functions.

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Nonalcoholic fatty liver disease (NAFLD) affects an estimated 17% of pregnant patients in the USA. However, there are limited data on the impact of maternal NAFLD on pediatric outcomes. We prospectively evaluated outcomes in infants born to mothers with and without NAFLD in pregnancy over their first 2 years of life.

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Organ size is maintained by the controlled proliferation of distinct cell populations. In the mouse liver, hepatocytes in the midlobular zone that are positive for cyclin D1 (CCND1) repopulate the parenchyma at a constant rate to preserve liver mass. Here, we investigated how hepatocyte proliferation is supported by hepatic stellate cells (HSCs), pericytes that are in close proximity to hepatocytes.

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Hepatic stellate cells (HSCs) are the major cellular source of extracellular matrix production in the liver. Therefore, this cell population has received considerable attention in studies investigating fundamental features of hepatic fibrosis. However, the limited supply and ever-increasing demand for these cells, combined with the additional tightening of formal standards in animal welfare policy, make working with these primary cells increasingly difficult.

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Article Synopsis
  • Developing effective treatments for non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steatohepatitis (NASH) is complex due to their pathways leading to severe outcomes like cirrhosis, necessitating approaches that target metabolic issues, inflammation, and fibrosis.
  • Current treatment strategies include targeting inflammatory responses with nuclear receptor agonists and hormonal therapies, while also focusing on the impact of genetic variants and lifestyle changes.
  • The variability in disease progression among patients complicates the development of universally effective medications, as therapies also need to address the activation and deactivation of immune responses and liver cell activities.
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The field of hepatology has made impressive progress over its ~75 years of existence. Advances in understanding liver function and its dysregulation in disease, genetic determinants of disease, antiviral therapy, and transplantation have transformed the lives of patients. However, there are still significant challenges that require ongoing creativity and discipline, particularly with the emergence of fatty liver diseases, as well as managing autoimmune disease, cancer, and liver disease in children.

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Nonalcoholic fatty liver disease (NAFLD), including its more severe manifestation, nonalcoholic steatohepatitis (NASH), has a global prevalence of 20-25% and is a major public health problem. Its incidence is increasing in parallel to the rise in obesity, diabetes and metabolic syndrome. Progression from NASH to NASH-related hepatocellular carcinoma (HCC) (~2% of cases per year) is influenced by many factors, including the tissue and immune microenvironment, germline mutations in PNPLA3, and the microbiome.

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