Title:SRC-3/AIB-1 may Enhance Hepatic NFATC1 Transcription and Mediate Inflammation in a Tissue-Specific Manner in Morbid Obesity
Volume: 20
Issue: 2
Author(s): Athina Chasapi*, Konstantinos Balampanis, Anna Tanoglidi, Eleni Kourea, George I. Lambrou, Vaia Lambadiari, Fotios Kalfarentzos, Erifili Hatziagelaki, Maria Melachrinou and Georgia Sotiropoulou-Bonikou
Affiliation:
- Department of Pathology, Medical School, University of Patras, 26500 Patras,Greece
Keywords:
Obesity, diabetes, NFATc1, SRC-3/AIB-1, Inflammation, Liver (Hepar), metabolic syndrome.
Abstract:
Background: Obesity is a global epidemic which is associated with several cardiometabolic
comorbidities and is characterized by chronic, low grade systemic inflammation. Numerous biomarkers
have been implicated in the pathophysiology of the disease, including transcription factors and
coregulators. Steroid Receptor Coactivator (SRC)-family represent the master regulators of metabolic
pathways and their dysregulation is strongly associated with numerous metabolic disorders.
Methods: 50 morbidly obese patients participated in the present study. Biopsies were collected from
visceral adipose tissue, subcutaneous adipose tissue, skeletal muscle, extra-myocellular adipose tissue
and liver. We evaluated the differential protein expression of NFATc1, SRC-2/TIF-2, SRC-3/AIB-1
and inflammatory biomarkers CD68 and CD3 by immunohistochemistry. The current study was designed
to determine any correlations between the transcription factor NFATc1 and the SRC coregulators,
as well as any associations with the inflammatory biomarkers.
Results: We identified SRC-3 as a hepatic NFATc1 coactivator and we demonstrated its possible role
in energy homeostasis and lipid metabolism. Moreover, we revealed a complex and extensive intraand
inter-tissue network among the three main investigated proteins and the inflammatory biomarkers,
suggesting their potential participation in the obesity-induced inflammatory cascade.
Conclusion: Steroid receptor coactivators are critical regulators of human metabolism with pleiotropic
and tissue-specific actions. We believe that our study will contribute to the better understanding of the
complex multi-tissue interactions that are disrupted in obesity and can therefore lead to numerous cardiometabolic
diseases. Further on, our present findings suggest that SRC-3/AIB-1 could constitute
possible future drug targets.