title: Circulating ANGPTL8/Betatrophin Is Increased in Obesity and Reduced after Exercise Training.
abstract: OBJECTIVE
  ANGPTL8 is a liver and adipose tissue produced protein that regulates the level of triglyceride in plasma as well as glucose homeostasis. This study was designed to evaluate the level of ANGPTL8 in obese and non-obese subjects before and after exercise training.
  
  
  METHODS
  A total of 82 non-obese and 62 adult obese were enrolled in this study. Subjects underwent a three months of exercise training. Both full length and C-terminal 139-198 form of ANGPTL8 were measured by ELISA.
  
  
  RESULTS
  Our data show that the full length ANGPTL8 level was increased in obese subjects (1150.04 ± 108.10 pg/mL) compared to non-obese (775.54 ± 46.12) pg/mL (p-Value = 0.002). C-terminal 139-198 form of ANGPTL8 was also increased in obese subjects 0.28 ± 0.04 ng/mL vs 0.20 ± 0.02 ng/mL in non-obese (p-value = 0.058). In obese subjects, the levels of both forms were reduced after three months of exercise training; full length was reduced from 1150.04 ± 108.10 pg/mL to 852.04 ± 51.95 pg/mL (p-Values 0.015) and c-terminal form was reduced from 0.28 ± 0.04 ng/mL to 0.19 ± 0.03 ng/mL (p-Value = 0.058). Interestingly, full length ANGPTL8 was positively associated with fasting blood glucose (FBG) in non-obese (r = 0.317, p-Value = 0.006) and obese subjects (r = 0.346, p-Value = 0.006) C-terminal 139-198 form of ANGPTL8 on the other hand, did not show any correlation in both groups.
  
  
  CONCLUSIONS
  In conclusion, our data demonstrate that ANGPTL8 was increased in obesity and reduced after exercise training supporting the potential therapeutic benefit of reducing ANGPTL8. The various forms of ANGPTL8 associated differently with FBG suggesting that they have different roles in glucose homeostasis.
authors.affiliation: Biochemistry and Molecular Biology Unit, Dasman Diabetes Institute, Kuwait City, Kuwait.
authors.forename: Mohamed
authors.initials: M
authors.lastname: Abu-Farha
authors.affiliation: Tissue Banking Unit, Dasman Diabetes Institute, Kuwait City, Kuwait.
authors.forename: Devarajan
authors.initials: D
authors.lastname: Sriraman
authors.affiliation: Biochemistry and Molecular Biology Unit, Dasman Diabetes Institute, Kuwait City, Kuwait.
authors.forename: Preethi
authors.initials: P
authors.lastname: Cherian
authors.affiliation: Biochemistry and Molecular Biology Unit, Dasman Diabetes Institute, Kuwait City, Kuwait.
authors.forename: Irina
authors.initials: I
authors.lastname: AlKhairi
authors.affiliation: Sidra Medical and Research Center, Doha, Qatar.
authors.forename: Naser
authors.initials: N
authors.lastname: Elkum
authors.affiliation: Biochemistry and Molecular Biology Unit, Dasman Diabetes Institute, Kuwait City, Kuwait.|Tissue Banking Unit, Dasman Diabetes Institute, Kuwait City, Kuwait.
authors.forename: Kazem
authors.initials: K
authors.lastname: Behbehani
authors.affiliation: Biochemistry and Molecular Biology Unit, Dasman Diabetes Institute, Kuwait City, Kuwait.
authors.forename: Jehad
authors.initials: J
authors.lastname: Abubaker
mesh_terms: D000328:Adult; D000091306:Angiopoietin-Like Protein 8; D000075802:Angiopoietin-like Proteins; D001786:Blood Glucose / Q000378:metabolism; D005080:Exercise Test / Q000379:methods*; D005786:Gene Expression Regulation; D006801:Humans; D008875:Middle Aged; D009765:Obesity / Q000097:blood / Q000378:metabolism*; D036361:Peptide Hormones / Q000097:blood*; D020033:Protein Isoforms / Q000097:blood; D015854:Up-Regulation
chemical_list: C576683:ANGPTL8 protein, human; D000091306:Angiopoietin-Like Protein 8; D000075802:Angiopoietin-like Proteins; D001786:Blood Glucose; D036361:Peptide Hormones; D020033:Protein Isoforms