Protein expression levels and the significances of nuclear factor-kappa B, interleukin-18 and substance P in degenerative endplates with type Ⅱ Modic changes

English Keywords:Modic Ⅱ changes  Low back pain  Nuclear factor-kappa B  Interleukin-18  Substance P

English Abstract:

  【Abstract】 Objectives: To investigate the protein expression levels and significances of nuclear factor-kappa B (NF-κB), interleukin(IL)-18 and substance P(SP) in degenerative endplates with type Ⅱ Modic changes (MCs). Methods: Forty-one patients who received single level interbody fusion from October 2010 to October 2011(18 males, 23 females) and with a mean age of 47.13±13.67 years(range, 20-70 years) were included in the study. Patients were divided into 2 groups: group A, type Ⅱ MCs on magnetic resonance imaging(MRI) and group B, without MCs. In addition, 5 patients(3 males, 2 females) with a mean age of 24.20±3.70 years with lumbar vertebral fractures were included as control group (group C). Endplate specimens were stained with hematoxylin and eosin(HE) and observed with light microscopy. Concentrations of NF-κB, IL-18 and SP were detected by immunochemistry. Results: Light microscopy showed no obvious degeneration in group C, and the staining of group B was lighter than that of group A. The positive cell index of NF-κB in group A, B and C was 55.39±17.74, 36.01±14.80 and 4.42±2.84 respectively. That of IL-18 in group A, B and C was 45.23±12.95, 30.22±12.01 and 5.22±3.46 respectively. That of SP in group A, B and C was 38.29±19.26, 25.83±16.52 and 0.97±1.32 respectively. Immunochemistry showed that the positive cell indexes of NF-κB, IL-18 and SP in group A and B were higher than those in group C(P<0.05), and group A was higher than group B(P<0.05). A positive relationship between the levels of NF-κB and IL-18 was noted(P<0.05). Conclusions: The early results of interbody fusion are better than simple discectomy for single segmental LDH when type Ⅱ MCs occur in lumbar endplates, the protein expression levels of NF-κB, IL-18 and SP in cartilage endplates will increase. Elevated levels of NF-κB, IL-18 and SP may be the cause of low back pain in patients with degenerative endplates with type II MCs.