Effect of methylene blue on intra-abdominal adhesion formation in rats

Abstract

a b s t r a c tBackground: Adhesion formation represents an important clinical challenge in gastro-intestinal surgery. In the late era, methylene blue (MB) has been claimed to play a helping role in combating such a problem. In the present study, we investigated the effects of MB administered intraperitoneally on the surgically-induced adhesions in rats and tried to clarify whether its impact is concentration-dependent.Material & Methods: Seventy adult male Wistar rats were used. They were allocated into seven groups, ten rats each: one control, two sham-operated and four experimental ones. Peritoneal adhesions were evoked by scraping the cecal serosa in the four experimental groups which were given different concentrations of MB, intraperitoneally. The animals of the control group were similarly dealt but were given saline. The rats of the sham-operated groups were given either MB or saline but without any serosal damage.Results: After the elapse of two weeks, the resulting adhesions, inflammation and fibrosis were evaluated. In the rats treated with MB 1%, adhesions, inflammatory process and fibrosis scores were similar to those in the sham-operated rats and were significantly lower than those in all other groups.Conclusion: It could be concluded that MB, 1%, had the best anti-adhesion potential.

Abdominal Adhesion Prevention: Still a Sticky Subject

“…The risk of bleeding associated with NSAIDs, or impaired wound healing with steroid use, has limited their use in the clinical setting. More recently, free radical scavengers [34,96,97] including methylene blue [105] as well as inhibitors of pro-inflammatory cytokines [35] and antihistamines [36,37,72,73,74] have been trialled. Although there have been promising results from animal studies, no single agent has progressed to widespread clinical use.…”

Abdominal Adhesions: Current and Novel Therapies

“…Increases cGMP leading to reduced collagen synthesis and increases in fibroblast apoptosis [276,277] Some efficacy in rat models (oral delivery) [278,279] Increased colonic bursting pressure and angiogenesis in rat model in the presence of infection [279] Methylene blue Inhibits NO synthase; reduces free radical oxygen but mechanism in preventing adhesions unknown [280] Some efficacy in rat models [280][281][282] May induce adhesions at high doses [280] Impairs anastomotic healing [282] Catalase Reduces oxidative stress Some efficacy in rat model [283] Vitamin E Antioxidant Efficacy comparable to Seprafilm in rat model [284] Opioids (opium, morphine) Unknown mechanism; postulated that opium receptor decreases inflammation [285] Some efficacy in rat model (reduced length, thickness, and severity) [285] (Continued ) WARD AND PANITCH: ABDOMINAL ADHESIONS: PATHOGENESIS AND SOLUTIONS May reduce oxidative stress [286] Some efficacy in rat bacterial peritonitis model [286] Mixture of lidocaine and prilocaine more effective than lidocaine alone [286] Honey Unknown mechanism; may reduce oxidative stress [287] Some efficacy in rat model (oral delivery [288] and peritoneal delivery [287]) Improved histology and anastomotic busting pressure in rats [288] Sphingosine kinase 1 delivered by adenovirus Enhances mesothelial cell migration accelerating wound healing [289] Some efficacy in rat model [289] neurokinin-1 receptor antagonist (aprepitant, CJ-12-255]…”

Methylene blue 1% solution on the prevention of intraperitoneal adhesion formation in a dog model

“…Thus, the reduced rate of colonic adhesions was probably reached due to the antioxidant mechanism of MB solution over the colonic serosa and consequent enhanced fi brinolysis. Such hypothesis was confi rmed in other trials involving the uterine horn deserosation (KLUGER et al, 2000;YILDIZ et al, 2011) or cauterization (CETIN et al, 2003), cecal serosa damage (RAŞA et al, 2002;MAHDY et al, 2008), section and anastomosis of the right colon (DINC et al, 2006) and parietal peritoneum ischemia (HEYDRICK et al, 2007) in blinded controlled trials rats.…”

“…Intraperitoneal MB solution attenuates postsurgical oxidative stress and decreases intraperitoneal adhesion formation enhancing peritoneal fi brinolysis (BINDA et al, 2003;MAHDY et al, 2008). Such effect is attributed to the decline of oxidative stress following neutralization of the instable electron from molecules of xanthine oxidase and NADPH-oxidase (HEYDRICK et al, 2007).…”