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Dive into the research topics where Amon Asgharpour is active.

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Featured researches published by Amon Asgharpour.


Journal of Hepatology | 2016

A diet-induced animal model of non-alcoholic fatty liver disease and hepatocellular cancer.

Amon Asgharpour; Sophie C. Cazanave; Tommy Pacana; Mulugeta Seneshaw; Robert Vincent; B. Banini; Divya P. Kumar; Kalyani Daita; Hae-Ki Min; Faridoddin Mirshahi; Pierre Bedossa; Xiaochen Sun; Yujin Hoshida; Srinivas V. Koduru; Daniel Contaifer; Urszula Osinska Warncke; Dayanjan S. Wijesinghe; Arun J. Sanyal

Background & Aims The lack of a preclinical model of progressive non-alcoholic steatohepatitis (NASH) that recapitulates human disease is a barrier to therapeutic development. Methods A stable isogenic cross between C57BL/6J (B6) and 129S1/SvImJ (S129) mice were fed a high fat diet with ad libitum consumption of glucose and fructose in physiologically relevant concentrations and compared to mice fed a chow diet and also to both parent strains. Results Following initiation of the obesogenic diet, B6/129 mice developed obesity, insulin resistance, hypertriglyceridemia and increased LDL-cholesterol. They sequentially also developed steatosis (4–8 weeks), steatohepatitis (16–24 weeks), progressive fibrosis (16 weeks onwards) and spontaneous hepatocellular cancer (HCC). There was a strong concordance between the pattern of pathway activation at a transcriptomic level between humans and mice with similar histological phenotypes (FDR 0.02 for early and 0.08 for late time points). Lipogenic, inflammatory and apoptotic signaling pathways activated in human NASH were also activated in these mice. The HCC gene signature resembled the S1 and S2 human subclasses of HCC (FDR 0.01 for both). Only the B6/129 mouse but not the parent strains recapitulated all of these aspects of human NAFLD. Conclusions We here describe a diet-induced animal model of non-alcoholic fatty liver disease (DIAMOND) that recapitulates the key physiological, metabolic, histologic, transcriptomic and cell-signaling changes seen in humans with progressive NASH. Lay summary We have developed a diet-induced mouse model of non-alcoholic steatohepatitis (NASH) and hepatic cancers in a cross between two mouse strains (129S1/SvImJ and C57Bl/6J). This model mimics all the physiological, metabolic, histological, transcriptomic gene signature and clinical endpoints of human NASH and can facilitate preclinical development of therapeutic targets for NASH.


Hepatology International | 2015

Bile acids: emerging role in management of liver diseases.

Amon Asgharpour; Divya P. Kumar; Arun J. Sanyal

Bile acids are well known for their effects on cholesterol homeostasis and lipid digestion. Since the discovery of bile acid receptors, of which there are farnesoid X receptor (FXR), a nuclear receptor, and the plasma membrane G-protein receptor, as well as Takeda G-protein coupled receptor clone 5, further roles have been elucidated for bile acids including glucose and lipid metabolism as well as inflammation. Additionally, treatment with bile acid receptor agonists has shown a decrease in the amount of atherosclerosis plaque formation and decreased portal vascular resistance and portal hypotension in animal models. Furthermore, rodent models have demonstrated antifibrotic activity using bile acid receptor agonists. Early human data using a FXR agonist, obeticholic acid, have shown promising results with improvement of histological activity and even a reduction of fibrosis. Human studies are ongoing and will provide further information on bile acid receptor agonist therapies. Thus, bile acids and their derivatives have the potential for management of liver diseases and potentially other disease states including diabetes and the metabolic syndrome.


Hepatology | 2017

Dual-photon microscopy-based quantitation of fibrosis-related parameters (q-FP) to model disease progression in steatohepatitis

Yan Wang; Robert Vincent; Jinlian Yang; Amon Asgharpour; Xieer Liang; Michael O. Idowu; Melissa J. Contos; Kalyani Daitya; Mohammed S. Siddiqui; Faridoddin Mirshahi; Arun J. Sanyal

There is a need for further refinement of current histological systems for assessment of hepatic fibrosis in nonalcoholic fatty liver disease (NAFLD). This study evaluated hepatic fibrosis in NAFLD using dual‐photon microscopy‐based quantitation of fibrosis‐related parameters (q‐FPs). Fifty test cohort subjects and 42 validation cohort subjects with NAFLD and the full spectrum of fibrosis were studied. q‐FPs were measured in specific predefined regions of interest (general, vessel, perisinusoid, and vascular septa). Seventy q‐FPs had inter‐ and intraobserver concordance ≥0.8 and were related to the NASH Clinical Research Network fibrosis staging. Of these, 16 q‐FPs with the strongest correlations (P < 0.001 for all) were entered in a principal component analysis model (odds ratio [OR] 7.8, P < 0.001), which separated any stage of fibrosis versus no fibrosis, and cirrhosis versus earlier stages with the areas under the receiver operating characteristic curves of 0.88 and 0.93 (P ≤ 0.01 for both), respectively. In an independent multivariable analysis, four q‐FPs—the number of collagen strands (OR 8.5, P = 0.004), strand length (OR 12.0, P = 0.02), strand eccentricity (OR 8.3, P = 0.004), and strand solidity (OR 8.0, P = 0.003)—were independently associated with fibrosis stages and were used to model fibrosis along a continuous linear scale using desirability functions; this linear scale of fibrosis measurement was also related to fibrosis stage (P < 0.0001). The robustness of both the multivariable model and the linear scale of measurement was confirmed in the validation cohort. Conclusion: The q‐FP model provides an accurate reproducible method to evaluate fibrosis in NAFLD along a quantitative and continuous scale. (Hepatology 2017;65:1891‐1903).


Scientific Reports | 2018

An Evaluation of the Collagen Fragments Related to Fibrogenesis and Fibrolysis in Nonalcoholic Steatohepatitis

Yi Luo; Abdul M. Oseini; Robert Gagnon; Edgar D. Charles; Kurex Sidik; Robert Vincent; Rebeca Collen; Michael O. Idowu; Melissa J. Contos; Faridoddin Mirshahi; Kalyani Daita; Amon Asgharpour; Mohammed S. Siddiqui; Gabor Jarai; Glenn D. Rosen; Rose Christian; Arun J. Sanyal

Fibrosis, resulted from the imbalance of fibrogenesis and fibrolysis, is a key readout of disease progression in nonalcoholic steatohepatitis (NASH) and reflects mortality risk. Non-invasive biomarkers capable of diagnosing fibrosis stages and monitoring fibrosis changes in NASH patients are urgently needed. This study is to evaluate collagen formation and degradation biomarkers, reflective of fibrogenesis or fibrolysis, in patients with biopsy proven NASH. Collagen formation biomarker PRO-C3 and PRO-C6 levels were significantly higher in patients with advanced fibrosis stage 3–4 than those with fibrosis stage 0–2. Elevated PRO-C3 levels were also associated with severe lobular inflammation and ballooning, but not with steatosis. Multivariate logistic regression analysis identified PRO-C3 and PRO-C6 to be independently related to fibrosis stage. PRO-C3 showed similar performance to identify patients with advanced fibrosis in discovery and validation cohorts. Furthermore, in a longitudinal study cohort with paired biopsies, mean PRO-C3 increased with worsening of fibrosis and decreased with fibrosis improvement. The results suggest that PRO-C3 may be a potentially useful biomarker in identifying patients with advanced fibrosis and active fibrogenesis, as well as in assessing changes in fibrosis over time. It is worthy of further evaluation to confirm its diagnostic value and clinical utility.


Journal of Visualized Experiments | 2016

Fast and Simplified Method for High Through-put Isolation of miRNA from Highly Purified High Density Lipoprotein.

Mulugeta Seneshaw; Faridoddin Mirshahi; Hae-Ki Min; Amon Asgharpour; Shervin Mirshahi; Kalyani Daita; Sherry Boyett; Prasanna K. Santhekadur; Michael Fuchs; Arun J. Sanyal

Small non-coding RNAs (miRNAs) have been implicated in a variety of human diseases including metabolic syndromes. They may be utilized as biomarkers for diagnosis and prognosis or may serve as targets for drug development, respectively. Recently it has been shown that miRNAs are carried in lipoproteins, particularly high density lipoproteins (HDL) and are delivered to recipient cells for uptake. This raises the possibility that miRNAs play a critical and pivotal role in cellular and organ function via regulation of gene expression as well as messenger for cell-cell communications and crosstalk between organs. Current methods for miRNA isolation from purified HDL are impractical when utilizing small samples on a large scale. This is largely due to the time consuming and laborious methods used for lipoprotein isolation. We have developed a simplified approach to rapidly isolate purified HDL suitable for miRNA analysis from plasma samples. This method should facilitate investigations into the role of miRNAs in health and disease and in particular provide new insights into the variety of biological functions, outside of the reverse cholesterol transport, that have been ascribed to HDL. Also, the miRNA species which are present in HDL can provide valuable information of clinical biomarkers for diagnosis of various diseases.


Journal of Hepatology | 2015

P0953 : FXR resistance characterizes human and mouse model of NASH

Sophie C. Cazanave; Robert Vincent; J. Srivastava; Amon Asgharpour; M. Sheneshaw; Faridoddin Mirshahi; D. Prasanna Kumar; Puneet Puri; Devanand Sarkar; Arun J. Sanyal


Journal of Hepatology | 2015

P0971 : A diet-induced mouse model of nonalcoholic fatty liver disease with progression to advanced fibrosis and hepatocellular carcinoma with a gene expression signature mimicking human disease

Amon Asgharpour; Pierre Bedossa; Yujin Hoshida; Sophie C. Cazanave; Robert Vincent; Tommy Pacana; Faridoddin Mirshahi; M. Sheneshaw; Kalyani Daita; Puneet Puri; Arun J. Sanyal


Journal of Hepatology | 2016

Omega-3 Carboxylic Acids, Epanova®, and the Sodium-Glucose Co-Transporter 2 Inhibitor, Dapagliflozin®, Improve Steatohepatitis and Fibrosis Scoring in a Mouse Model of Non-Alcoholic Steatohepatitis

Sophie C. Cazanave; B. Banini; Amon Asgharpour; Robert Vincent; Mulugeta Seneshaw; D. Prassana Kumar; Faridoddin Mirshahi; Kalyani Daita; Puneet Puri; J. Oscarsson; Pierre Bedossa; Arun J. Sanyal


The FASEB Journal | 2015

Regulation of pancreatic β cell function by GLP-1 released from α cells in response to activation of TGR5 by bile acids

Divya P. Kumar; Amon Asgharpour; Fariddodin Mirshahi; John R. Grider; Karnam S. Murthy; Arun J. Sanyal


Journal of Hepatology | 2015

O044 : Distinct fecal and plasma bile acid metabolome of microbial origin characterizes human nonalcoholic fatty liver disease (NAFLD)

Puneet Puri; S.M. Siddiqui; S. Boyette; C. Sargeant; L.D. White; S. Walker; Kalyani Daita; C. Ammons; Sophie C. Cazanave; Amon Asgharpour; Faridoddin Mirshahi; A. Joyce; Arun J. Sanyal

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Arun J. Sanyal

Virginia Commonwealth University

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Faridoddin Mirshahi

Virginia Commonwealth University

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Robert Vincent

Virginia Commonwealth University

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Kalyani Daita

Virginia Commonwealth University

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Puneet Puri

Virginia Commonwealth University

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Divya P. Kumar

Virginia Commonwealth University

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Mulugeta Seneshaw

Virginia Commonwealth University

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B. Banini

Virginia Commonwealth University

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