Morphometric analysis of the collagen changes induced by subcutaneous injection of interferon-gamma after bladder outlet obstruction in the rat

Evaluation of the effects of omega-3 & interferon alpha-2b administration on partial bladder outlet obstruction in a rat model

BACKGROUND & OBJECTIVES

In bladder outlet obstruction-induced rat models, the transforming growth factor-beta (TGF-β) and collagen ratios have been shown to be increased. Increased TGF-β leads to fibrosis. In this study, the effect of omega-3 and interferon alpha-2b (IFN α-2b) was investigated on oxidative stress, inflammation and fibrosis in bladder structure in a partial bladder outlet obstruction (PBOO) rat model.

METHODS

A total of 35 male Wistar albino rats, weighing 300-350 g, were used in the study. The rats were randomly divided into five groups. At the end of the experimental period, bladders were harvested from all the rats, and pathological analysis of the rat bladder tissues was performed. In addition, investigations were carried out with enzymatic and non-enzymatic antioxidant systems to study the antioxidant properties of omega-3 fatty acid and IFN alpha-2b.

RESULTS

Increased bladder weight in the PBOO group, in comparison to the control group, was decreased by the administration of omega-3 and IFN α-2b (P=0.002). Significantly higher superoxide dismutase (SOD) levels were detected in group 2 in comparison to the control group. It was also detected that serum SOD, glutathione peroxidase and nitric oxide (NO) levels were significantly higher in group 2 when compared to the control group (P<0.05). In the pathologic evaluation, group 2 showed significantly increased inflammation and fibrosis compared to the control group. Omega-3 treatment significantly decreased inflammation. It was shown that IFN α-2b application partially decreased inflammation.

INTERPRETATION & CONCLUSIONS

The results of the present study showed that in addition to the standard primary approaches to prevent the damage to the upper urinary tract secondary to PBOO, omega-3 fatty acid and IFN α-2b could be beneficial as adjunct treatment in clinical practice. However, this needs to be further investigated with prospective, randomized clinical trials with larger sample sizes.

In Vivo Hepatocyte Growth Factor Gene Transfer to Bladder Smooth Muscle After Bladder Outlet Obstruction in the Rat: A Morphometric Analysis

PURPOSE

We determined whether hepatocyte growth factor gene transfer after partial bladder outlet obstruction would prove effective for decreasing transforming growth factor-beta expression and consequently decreasing collagen deposition in partially obstructed rat bladders.

MATERIALS AND METHODS

Ten-week-old male Sprague-Dawley rats were divided into 3 groups of 10 each, including group 1--sham operation, group 2--bladder outlet obstruction for 4 weeks and group 3--hepatocyte growth factor gene transfer after bladder outlet obstruction. Two weeks after the onset of bladder outlet obstruction in group 3 hepatocyte growth factor-liposome complex (50 microg human hepatocyte growth factor cDNA) was injected into the smooth muscle of the rats.

RESULTS

We noted no difference between groups 2 and 3 with regard to the ratio of bladder weight to body weight. The ratio in groups 2 and 3 was significantly higher than in group 1 (p = 0.043). The mean percent of collagen area +/- SE was 36.32% +/- 1.83%, 27.90% +/- 2.66% and 8.97% +/- 3.35% in groups 1 to 3, respectively (p <0.05). Relative hepatocyte growth factor and c-met mRNA and protein expression were higher in group 3 than in groups 1 and 2. However, the expression of transforming growth factor-beta1 mRNA and protein was higher in group 2 than in groups 1 and 3.

CONCLUSIONS

These findings may imply a possible novel therapeutic strategy against bladder dysfunction arising in patients with bladder outlet obstruction.