title: Targeted deletion of fibrinogen like protein 1 reveals a novel role in energy substrate utilization.
abstract: Fibrinogen like protein 1(Fgl1) is a secreted protein with mitogenic activity on primary hepatocytes. Fgl1 is expressed in the liver and its expression is enhanced following acute liver injury. In animals with acute liver failure, administration of recombinant Fgl1 results in decreased mortality supporting the notion that Fgl1 stimulates hepatocyte proliferation and/or protects hepatocytes from injury. However, because Fgl1 is secreted and detected in the plasma, it is possible that the role of Fgl1 extends far beyond its effect on hepatocytes. In this study, we show that Fgl1 is additionally expressed in brown adipose tissue. We find that signals elaborated following liver injury also enhance the expression of Fgl1 in brown adipose tissue suggesting that there is a cross talk between the injured liver and adipose tissues. To identify extra hepatic effects, we generated Fgl1 deficient mice. These mice exhibit a phenotype suggestive of a global metabolic defect: Fgl1 null mice are heavier than wild type mates, have abnormal plasma lipid profiles, fasting hyperglycemia with enhanced gluconeogenesis and exhibit differences in white and brown adipose tissue morphology when compared to wild types. Because Fgl1 shares structural similarity to Angiopoietin like factors 2, 3, 4 and 6 which regulate lipid metabolism and energy utilization, we postulate that Fgl1 is a member of an emerging group of proteins with key roles in metabolism and liver regeneration.
authors.affiliation: Division of Gastroenterology, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, United States of America.
authors.forename: Valeriy
authors.initials: V
authors.lastname: Demchev
authors.forename: Geraldine
authors.initials: G
authors.lastname: Malana
authors.forename: Divya
authors.initials: D
authors.lastname: Vangala
authors.forename: Janis
authors.initials: J
authors.lastname: Stoll
authors.forename: Anal
authors.initials: A
authors.lastname: Desai
authors.forename: Hye Won
authors.initials: HW
authors.lastname: Kang
authors.forename: Yingxia
authors.initials: Y
authors.lastname: Li
authors.forename: Hamed
authors.initials: H
authors.lastname: Nayeb-Hashemi
authors.forename: Michele
authors.initials: M
authors.lastname: Niepel
authors.forename: David E
authors.initials: DE
authors.lastname: Cohen
authors.forename: Chinweike
authors.initials: C
authors.lastname: Ukomadu
mesh_terms: D002001:Adipose Tissue, Brown / Q000378:metabolism; D000818:Animals; D001835:Body Weight; D002153:Calorimetry, Indirect; D002784:Cholesterol / Q000097:blood; D004734:Energy Metabolism; D005215:Fasting / Q000097:blood; D005230:Fatty Acids, Nonesterified / Q000097:blood; D005247:Feeding Behavior; D005340:Fibrinogen / Q000378:metabolism*; D017353:Gene Deletion; D018390:Gene Targeting; D005947:Glucose / Q000378:metabolism; D006943:Hyperglycemia / Q000378:metabolism; D008055:Lipids / Q000097:blood; D008099:Liver / Q000378:metabolism; D051379:Mice; D018345:Mice, Knockout; D009929:Organ Size
chemical_list: D005230:Fatty Acids, Nonesterified; C476403:Fgl1 protein, mouse; D008055:Lipids; D005340:Fibrinogen; D002784:Cholesterol; D005947:Glucose