British Journal of Nutrition

Full Papers

Human and Clinical Nutrition

Cystatin C levels in plasma and peripheral blood mononuclear cells among hyperhomocysteinaemic subjects: effect of treatment with B-vitamins

Kari Anne R. Tobina1a2, Kirsten B. Holvena3, Kjetil Retterstøla1, Ellen Strøma1, Leiv Osea1, Pål Aukrusta2a4 and Marit S. Nensetera1a2 c1

a1 Lipid Clinic, Oslo University Hospital, Rikshospitalet, 0027 Oslo, Norway

a2 Research Institute for Internal Medicine, Oslo University Hospital, Rikshospitalet, University of Oslo, 0027 Oslo, Norway

a3 Department of Nutrition, Institute for Basic Medical Sciences, University of Oslo, Oslo, Norway

a4 Section of Clinical Immunology and Infectious Diseases, Oslo University Hospital, Rikshospitalet, University of Oslo, 0027 Oslo, Norway


Homocysteine has been related to increased risk of CVD. Matrix degradation and inflammation may be involved in this link between hyperhomocysteinaemia and CVD. Recent studies suggest that cystatin C can modulate matrix degradation and inflammation. The present study measured cystatin C at protein (plasma) and mRNA levels (peripheral blood mononuclear cells (PBMC)) in hyperhomocysteinaemic individuals (n 37, female seven and male thirty, aged 20–70 years) before and after B-vitamin supplementation for 3 months in a randomised, placebo-controlled double-blind trial. In a cross-sectional study, seventeen of the hyperhomocysteinaemic subjects were age- and sex-matched to healthy controls (n 17). Our main findings were: (i) as compared with controls, hyperhomocysteinaemic subjects tended to have higher plasma concentrations of cystatin C and lower mRNA levels of cystatin C in PBMC; (ii) compared with placebo, treatment of hyperhomocysteinaemic individuals with B-vitamins significantly increased plasma levels of cystatin C and mRNA levels of cystatin C in PBMC; (iii) while plasma levels of cystatin C were positively correlated with plasma levels of TNF receptor-1, mRNA levels of cystatin C in PBMC were inversely correlated with this TNF parameter. Taken together, our findings suggest that disturbed cystatin C levels may be a characteristic of hyperhomocysteinaemic individuals, potentially related to low-grade systemic inflammation in hyperhomocysteinaemic subjects, and that B-vitamins may modulate cystatin C levels in these individuals.

(Received March 25 2009)

(Revised June 17 2009)

(Accepted June 22 2009)

(Online publication August 17 2009)


c1 Corresponding author: Marit S. Nenseter, fax +47 23073630, email


Abbreviations: PBMC, peripheral blood mononuclear cells; TNFR, TNF receptor