Collagen metabolism in obesity: the effect of weight loss

Int J Obes Relat Metab Disord. 1995 Sep;19(9):659-63.


Objective: To investigate the impact of obesity, fat distribution and weight loss on collagen turnover using serum concentrations of the carboxyterminal propeptide of type I procollagen (S-PICP) and the aminoterminal propeptide of type III pro-collagen (S-PIIINP) as markers for collagen turnover.

Design: Blood samples were obtained once at baseline, and after 8 and 16 weeks of dietary treatment (5.0 MJ/day diet).

Setting: Outpatient clinic of Hvidovre University Hospital.

Main outcome measures: S-PICP, S-PIIINP, fat distribution and weight loss.

Results: S-PIIINP was associated with body weight (r = 0.37; P = 0.004), height (r = 0.27; P = 0.04), waist circumference (r = 0.35; P = 0.007), as well as with WHR (r = 0.33; P = 0.01) and was inversely correlated to age (r = -0.40; P = 0.002). Compared with randomly selected controls from a large pool of healthy volunteers, the obese patients had elevated S-PIIINP values before as well as during weight loss, whereas S-PICP levels were within the normal range and did not correlate with any anthropometric measures. The average weight loss after 16 weeks dietary treatment was 8.1 kg (s.d. = 0.8). S-PIIINP decreased during the 16 weeks of energy restriction (P < 0.05) and changes in S-PIIINP was correlated to body weight loss (r = 0.32; P < 0.05) and to changes in waist circumference (r = 0.34; P < 0.05) as well as changes in WHR (r = 0.30; P < 0.05).

Conclusion: S-PIIINP is elevated in obesity and associated with body fat distribution, suggesting an increased turnover of type III collagen related to obesity in general and to abdominal obesity in particular. S-PIIINP levels decreases during weight loss in obese subjects, whereas S-PICP levels seems un-related to obesity and weight loss.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Anthropometry
  • Body Constitution / physiology
  • Body Weight / physiology
  • Collagen / metabolism*
  • Fatty Acids, Nonesterified / blood
  • Female
  • Humans
  • Male
  • Middle Aged
  • Obesity / metabolism*
  • Peptide Fragments / metabolism*
  • Procollagen / metabolism*
  • Weight Loss / physiology*


  • Fatty Acids, Nonesterified
  • Peptide Fragments
  • Procollagen
  • procollagen Type III-N-terminal peptide
  • procollagen type I carboxy terminal peptide
  • Collagen