Omega-3 polyunsaturated fatty acids: a modified approach for chemo-prevention of bladder cancer in a rat model and molecular studies of antineoplastic mechanisms.

OBJECTIVES: To test the chemo-preventative effects of omega-3 against bladder cancer (BC) induction in a rat model and its potential antineoplastic mechanisms. MATERIAL AND METHODS: Ninety male Fisher rats were divided into three groups during a 22-week protocol: group 1 (control), group 2 (Placebo + N-butyl-N-4- hydroxybutyl nitrosamine (BBN) for induction of BC and group 3 received omega-3 (1200 mg/kg/day) + BBN. At the end, blood samples and bladder tissues were collected and checked for the presence of malignancy, markers of angiogenesis (VEGF relative gene expression), inflammation (IL-6), proliferation (KI-67 expressions), oxidative stress (serum MDA and serum SOD) and epigenetic control (miRNA-145 level). RESULTS: At the end of the study, 60% and 86.6% rats survived in group 2 and 3 with significant weight loss among rats in group 2 when compared with other groups. In group 2, all rats developed visible bladder lesions of which five and 13 developed squamous cell carcinoma (SCC) and transitional cell carcinoma (TCC). In omega3-treated group, only one developed low grade SCC and one developed high grade non- invasive TCC. Bladders from omega-3-treated rats showed lower expression ofKI-67 (p < 0.05), VEGF (p < 0.001) and IL-6 (p < 0.001) and significant higher expression of mi-RNA (p < 0.001). Also, omega-3-treated group showed statistically significant lower MDA level (p < 0.001). CONCLUSION: Omega-3 inhibits bladder tumor growth in the BBN-induced BC rat model, due to anti-inflammatory, antioxidant, anti-proliferative, and anti-angiogenic properties together with epigenetic control.

Preventive effect of pomegranate juice against chemically induced bladder cancer: An experimental study.

OBJECTIVES: Pomegranate juice (PJ) is rich in important compounds with anti-cancer activities. This study aims to investigate the preventive effect of pomegranate juice (PJ) against bladder cancer (BC). METHODS: Eighty male Sprague Dawley rats were randomly classified into 4 equal groups: (1) Normal controls; (2) PJ group: supplied by PJ for 12 weeks; (3) Cancer-induced group: intake 0.05% v/v N-butyl-N-(4-hydroxybutyl)-nitrosamine (BBN) for 8 weeks; (4) Cancer-prevented group: BBN + PJ. After 12 weeks, all rats were sacrificed and their urinary bladder tissues were subjected to histopathological and immunohistochemical (p53) examinations, expression of interleukin 6 (IL-6), tumor necrosis factor alpha (TNF-α), hypoxia-inducible factor 1 (HIF-1) and the tumor protein p53 (TP53) and analysis of oxidative stress markers. RESULTS: The development of BC was: 0/20 (0%) in normal, PJ and cancer-prevented groups and 20/20 (100%) in cancer-induced group. Significant neoplastic lesions were observed in cancer-induced group. Mild preneoplastic alterations were noticed in 25% (5/20) of cancer-prevented group. p53 immunostaining were significantly elevated in the cancer-induced group, which was decreased in the cancer-prevented group. The relative expressions of IL-6, TNF-α, HIF-1 and TP53 were significantly lower in the cancer-prevented group compared to the cancer-treated group. Correction in the oxidative stress markers were also observed in the cancer-prevented group. CONCLUSION: PJ possesses a promising inhibitory effect on BC development, probably due to its anti-oxidant and anti-inflammatory properties.

Prophylaxis against renal ischemia-reperfusion injury in canine model: Stem cell approach.

INTRODUCTION: Stem cell therapy at the time of ischemia/reperfusion (I/R) injury has been hypothesized to attenuate the severity of acute kidney injury and to accelerate the regeneration process in lower animal models. Data in higher animal models is limited and discordant. We aimed to explore the reno-protective effects of stem cells on I/R related renal injury in a canine model. MATERIALS AND METHODS: Twenty-seven dogs that were treated with bone marrow-derived mesenchymal stem cells (BM-MSCs) were compared with another 27 dogs treated with adipose tissue-derived MSCs (AT-MSCs) following 90 min of warm ischemia to assess IR injury. Each group was divided into three subgroups (nine dogs each), according to the stem cell dose (5, 10, 15 × 106 in 500 µl volume) injected directly into the renal cortex after reperfusion. All dogs were re-evaluated by renogram, histopathology, and pro-inflammatory markers at 2 weeks, 2, and 3 months. RESULTS: In Group I, there was a mean reduction of creatinine clearance by 78%, 64%, and 74% at the three used doses, respectively, at 2 weeks. At 3 months, these kidneys regained a mean of 84%, 92%, and 72%, respectively, of its basal function. In Group II, the reduction of clearance was much more modest with mean of 14%, 6%, and 24% respectively at 2 weeks with more intense recovery of renal function by mean of 90%, 100%, and 76%, respectively, at 3 months. Group I had significantly more tubular necrosis and delayed regeneration compared with the Group II. Expressions of pro-inflammatory markers were upregulated in both the groups with a higher and more sustained expression in Group I. CONCLUSION: Stem cells protected against ischemic reperfusion injury in a canine model. AT-MSCs provided better protection than BM-MSCs.

Is solitary kidney really more resistant to ischemia? An experimental canine study.

PURPOSE: To our knowledge there are no evidence-based medicine data to date to critically judge the vulnerability of a solitary kidney to warm ischemia compared to paired kidneys. MATERIALS AND METHODS: Ten dogs were exposed to open right nephrectomy to create a solitary kidney model (group 1). Ten dogs with both kidneys were considered group 2. All dogs underwent warm ischemia by open occlusion of the left renal artery for 90 minutes. Dogs were sacrificed at different intervals (3 days to 4 weeks). All dogs were reevaluated by renogram before sacrifice and histopathology of the investigated kidney. The proinflammatory markers CD95 and tumor necrosis factor-α were assessed using real-time polymerase chain reaction. RESULTS: In group 1 clearance decreased by 20% at 1 week but basal function was regained starting at week 2. In group 2 clearance decreased more than 90% up to week 2. Recovery started at week 3 and by 4 weeks there was a 23% clearance reduction. Histopathological examination in group 1 revealed significant tubular necrosis (60%) at 3 days with regeneration starting at 1 week. In group 2 there was more pronounced tubular necrosis (90%) with regeneration starting at 2 weeks. The expression of proinflammatory markers was up-regulated in each group with higher, more sustained expression in group 2. CONCLUSIONS: Solitary kidney in a canine model is more resistant to ischemia than paired kidneys based on radiological, pathological and genetic evidence.

Effects of combined erythropoietin and epidermal growth factor on renal ischaemia/reperfusion injury: a randomized experimental controlled study.

OBJECTIVE: To investigate effects of combination of erythropoietin (EPO) and epidermal growth factor (EGF) on renal ischaemia and on reactive oxygen species in a rat model. MATERIALS AND METHODS: In all, 90 male Sprague-Dawley rats were allocated into five groups of 18, designated: Sham; treated with right nephrectomy only; Control, subjected to left renal ischaemia for 45 min with no treatment; EPO-treated, as the control but with EPO pretreatment; EGF-treated, as the control but with EGF pretreatment; EPO + EGF-treated, as the control but with EPO and EGF pretreatment. Renal function, histopathology and malondialdehyde (MDA), superoxide dismutase (SOD) and reduced glutathione (GSH) levels in kidneys were assessed at 1, 2 and 7 days after ischaemia. RESULTS: All rats except the controls had a significant improvement in serum creatinine, creatinine clearance and fractional excretion of Na(+) ; all three were significantly better in EPO + EGF group than in all other groups Histopathological examination showed marked structural damage in control rats. The tubular damage was least in the EPO + EGF group. The control group had a significant increase in MDA level and a significant decrease in SOD and GSH, while the EPO + EGF group had a marked significant reduction in MDA and increase in GSH and SOD. CONCLUSION: The protection against ischaemia/reperfusion injury might be maximal when EPO and EGF are administered concomitantly, and their protective effect might be partly due to their antioxidant effects.