Effect of Methyl Palmitate on the Formation of Epidural Fibrosis in an Experimental Epidural Fibrosis Model

ABSTRACT

Aim: To investigate the effects of local and systemic administration of methyl palmitate on the formation of epidural fibrosis. Material and Methods: Twenty-eight rats were randomly divided into four equal groups (control, Spongostan, local methyl palmitate and orally methyl palmitate) and laminectomy was performed between T11 and L1 in all rats. Local methyl palmitate (300 mg/kg) was applied with Spongostan; methyl palmitate (300 mg/kg) was given orally three times per week on different days for a total period of 4 weeks. Four weeks later, the vertebral column from T9 to L3, including the paraspinal muscles and epidural scar tissue, was removed en bloc and epidural fibrosis and arachnoidal involvement was graded and evaluated histopathologically. Kruskal-Wallis and Pearson Chi-Square test were used for statistical analysis. A statistically significant p-value was determined as p < 0.05. Results: The grading of epidural fibrosis was lower at a statistically significant level in orally-administrated methyl palmitate groups compared to the control and spongostan groups (p < 0.05). Conclusion: The findings of this study show that oral methyl palmitate decreases the formation of epidural fibrosis and that this effect of methyl palmitate could be mediated by reducing the functions of inflammatory cells such as macrophages, neutrophils and fibroblasts, including anti-inflammatory and antioxidant effects.

Keywords::

• laminectomy
• ınflammation
• failed back surgery
• epidural fibrosis
• methyl palmitate
• rat

Declaration of interest: The authors report no conflicts of interest. The authors alone are responsible for content and writing of the paper.

ABBREVIATIONS

(IP)	=	Intraperitoneal
(HCL)	=	Hydrochloride
(EF)	=	Epidural fibrosis
(MP)	=	Methyl palmitate
(NO)	=	Nitric oxide
(COX-2)	=	Cyclooxygenase-2
(LP)	=	Local methyl palmitate
(OP)	=	Oral methyl palmitate
(TNF-α)	=	Tumor necrosis factor alpha
(IL)	=	Interleukin
(TGF)	=	Transforming growth factor
(NF-κβ)	=	Nuclear factor kappa β