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Metabolic function of the CTRP family of hormones

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Abstract

Maintaining proper energy balance in mammals entails intimate crosstalk between various tissues and organs. These inter-organ communications are mediated, to a great extent, by secreted hormones that circulate in blood. Regulation of the complex metabolic networks by secreted hormones (e.g., insulin, glucagon, leptin, adiponectin, FGF21) constitutes an important mechanism governing the integrated control of whole-body metabolism. Disruption of hormone-mediated metabolic circuits frequently results in dysregulated energy metabolism and pathology. As part of an effort to identify novel metabolic hormones, we recently characterized a highly conserved family of 15 secreted proteins, the C1q/TNF-related proteins (CTRP1-15). While related to adiponectin in sequence and structural organization, each CTRP has its own unique tissue expression profile and non-redundant function in regulating sugar and/or fat metabolism. Here, we summarize the current understanding of the physiological functions of CTRPs, emphasizing their metabolic roles. Future studies using gain-of-function and loss-of-function mouse models will provide greater mechanistic insights into the critical role CTRPs play in regulating systemic energy homeostasis.

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Abbreviations

ACC:

Acetyl Co-A carboxylase

AgRP:

Agouti-related protein

AMPK:

AMP-activated protein kinase

CTRP:

C1q/TNF-related protein

C/EBP-α:

CCAAT/enhancer binding protein alpha

DIO:

Diet-induced obese

Erk1/2:

Extracellular signal-regulated protein kinases 1 and 2

eNOS:

Endothelial nitric oxide synthase

FACS:

Fluorescent activated cell sorter

GLUT4:

Glucose transporter 4

G6Pase:

Glucose-6-phosphatase

GPCR:

G-protein coupled receptor

GPI:

Glycosylphosphatidylinositol

JNK:

c-Jun N-terminal kinase

KO:

Knock-out

LKB1:

Liver kinase B1

L-ORD:

Late-onset retinal macular degeneration

MAPK:

Mitogen activated protein kinase

NPY:

Neuropeptide Y

PPAR-γ:

Peroxisome proliferator-activated receptor gamma

PCSK:

Proprotein convertase subtilisin/kexin

PEPCK:

Phosphoenolpyruvate carboxykinase

SAPK:

Stress-activated protein kinase

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Acknowledgment

G.W.W. is supported by grants from the National Institute of Health (DK084171) and the American Heart Association (SDG2260721).

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The authors have declared that no competing interests exist.

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  1. Department of Physiology and Center for Metabolism and Obesity Research, The Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA

    Marcus M. Seldin, Stefanie Y. Tan & G. William Wong

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  1. Marcus M. Seldin
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Correspondence to G. William Wong.

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Seldin, M.M., Tan, S.Y. & Wong, G.W. Metabolic function of the CTRP family of hormones. Rev Endocr Metab Disord 15, 111–123 (2014). https://doi.org/10.1007/s11154-013-9255-7

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