Beta-endorphin concentrations in peripheral blood mononuclear cells of patients with multiple sclerosis: effects of treatment with interferon beta

Arch Neurol. 2000 Aug;57(8):1178-81. doi: 10.1001/archneur.57.8.1178.


Context: It has been reported that the opioid peptide beta-endorphin (BE) has immunosuppressive effects. Interferon beta (IFN-beta) is a well-established therapy for multiple sclerosis (MS), but immunological mechanisms underlying its beneficial effects in MS are partially undefined.

Objectives: To determine BE levels in peripheral blood mononuclear cells (PBMCs) of patients with relapsing-remitting MS during different phases of disease activity and the possible modulating effects of IFN-beta treatment on PBMC BE synthesis in patients with MS.

Design: We measured BE levels in blood samples collected from 6 patients with MS who had not experienced clinical changes during the previous 3 months (patients with stable MS) and from 7 patients with MS during a clinical relapse. We also surveyed BE levels in PBMC samples from 8 patients with MS before treatment and for 6 months after the beginning of IFN-beta administration. The control group was 13 healthy subjects.

Results: Low PBMC BE levels were detected in patients with stable MS and in those entering IFN-beta treatment compared with control subjects. Increased BE concentrations were observed in MS patients experiencing a clinical relapse compared with patients with stable MS. During IFN-beta treatment, the levels of BE in PBMC samples from patients with MS increased significantly (after 1 month, P =.02; after 3 months, P =.007; and after 6 months, P =.16).

Conclusions: A reduction of BE levels was present in patients with clinically inactive MS. Treatment with IFN-beta seems to induce an increase of this opioid in PBMCs of MS patients. The increase of BE concentration during a clinical relapse may represent a possible control mechanism aimed at counterbalancing the inflammatory phase of the disease. Arch Neurol. 2000;57:1178-1181

MeSH terms

  • Adjuvants, Immunologic / therapeutic use
  • Adult
  • Female
  • Humans
  • Interferon-beta / therapeutic use
  • Leukocytes, Mononuclear / chemistry*
  • Leukocytes, Mononuclear / immunology*
  • Male
  • Multiple Sclerosis, Relapsing-Remitting / drug therapy
  • Multiple Sclerosis, Relapsing-Remitting / immunology*
  • Recurrence
  • beta-Endorphin / analysis*


  • Adjuvants, Immunologic
  • beta-Endorphin
  • Interferon-beta