Nonsynergistic effects of trimetazidine and selenium combination therapy on renal ischemic-reperfusion injury in rats

Trimetazidine an emerging paradigm in renal therapeutics: Preclinical and clinical insights

Trimetazidine (TMZ) is a well-known anti-ischemic agent used for the treatment of angina pectoris. In the past decades, the efficacy of this drug has been tested in a wide range of kidney injuries, including drug-induced nephrotoxicity (DIN), radio-contrast agent-induced nephropathy, and surgically induced renal ischemic injury. TMZhas renoprotective effects by attenuating oxidative stress, inflammatory cytokine release, maintaining oxygen and energy balance. Moreover, TMZ administration prevented kidney graft rejection in the porcine model by suppressing the infiltration of mononuclear cells, preserving mitochondrial functions, and maintaining Ca+ homeostasis. In DIN and diabetic kidney diseases,TMZ treatment prevents renal injury by inactivating immune cells, attenuating renal fibrosis, inflammation, apoptosis, and histological abnormalities. Interestingly, the clinical therapeutic efficacy of TMZ has also been documented in pre-existing kidney disease patients undergoing contrast exposure for diagnostic intervention. However, the mechanistic insights into the TMZ mediated renoprotective effects in other forms of renal injuries, including type-2 diabetes, drug-induced nephrotoxicity, and hypertension-induced chronic kidney diseases, remain uninvestigated and incomplete. Moreover, the clinical utility of TMZ as a renoprotective agent in radio-contrast-induced nephrotoxicity needs to be tested in a large patient population. Nevertheless, the available pieces of evidence suggest that TMZ is a promising and emerging renal therapy for the treatment and management of kidney diseases of variable etiologies. This review discusses the various pre-clinical and clinical findings and provides mechanistic insights into the TMZ mediated beneficial effects in various kidney diseases.

Comparison of pre-treatment and post-treatment use of selenium in retinal ischemia reperfusion injury

AIM

To investigate the effects of selenium in rat retinal ischemia reperfusion (IR) model and compare pre-treatment and post-treatment use.

METHODS

Selenium pre-treatment group (n=8) was treated with intraperitoneal (i.p.) selenium 0.5 mg/kg for 7d and terminated 24h after the IR injury. Selenium post-treatment group (n=8) was treated with i.p. selenium 0.5 mg/kg for 7d after the IR injury with termination at the end of the 7d period. Sham group (n=8) received i.p. saline injections identical to the selenium volume for 7d with termination 24h after the IR injury. Control group (n=8) received no intervention. Main outcome measures were retina superoxide dismutase (SOD), glutathione (GSH), total antioxidant status (TAS), malondialdehyde (MDA), DNA fragmentation levels, and immunohistological apoptosis evaluation.

RESULTS

Compared to the Sham group, selenium pre-treatment had a statistical difference in all parameters except SOD. Post-treatment selenium also resulted in statistical differences in all parameters except the MDA levels. When comparing selenium groups, the pre-treatment selenium group had a statistically higher success in reduction of markers of cell damage such as MDA and DNA fragmentation. In contrast, the post-selenium treatment group had resulted in statistically higher levels of GSH. Histologically both selenium groups succeeded to limit retinal thickening and apoptosis. Pre-treatment use was statistically more successful in decreasing apoptosis in ganglion cell layer compared to post-treatment use.

CONCLUSION

Selenium was successful in retinal protection in IR injuries. Pre-treatment efficacy was superior in terms of prevention of tissue damage and apoptosis.

Effects of trimetazidine in acute pancreatitis induced by L-arginine

BACKGROUND

In acute pancreatitis, oxygen free radicals (OFRs) and cytokines have been shown to play a role in the failure of pancreatic microcirculation and the development of local tissue damage. We studied the effects of trimetazidine (TMZ), a potent antioxidant and anti-ischemic agent, on acute pancreatitis.

METHODS

Rats were randomized into 3 groups: a control group (n = 15), a study group (n = 15) in which acute pancreatitis was induced with with L-arginine, and a treatment group (n = 15) in which pancreatitis was induced and treated with TMZ intraperitoneally. The rats were followed for 24 hours. At the 24th hour we determined serum levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), amylase, lactate dehydrogenase (LDH), interleukin 1-β (IL-1β), interleukin 6 (IL-6) and tumour necrosis factor-α (TNF-α), and the pancreatic tissues were analyzed histopathologically.

RESULTS

The AST (p < 0.001), ALT (p < 0.01), amylase (p < 0.001), LDH (p < 0.01), TNF-α (p < 0.01), IL-1β (p < 0.001) and IL-6 (p < 0.001) levels, and pancreatic tissue edema (p < 0.01), hemorrhage (p < 0.05), acinar cell necrosis (p < 0.001) and level of perivascular inflammation (p < 0.01), were significantly lower in the treatment group than the study group.

CONCLUSION

Trimetazidine markedly decreases biochemical and histopathologic changes during the early stages of acute pancreatitis, thus preserving the pancreas histologically.

Selenium has a protective effect on ischemia/reperfusion injury in a rat ovary model: biochemical and histopathologic evaluation

BACKGROUND/PURPOSE

The aim of the study was to evaluate the effects of selenium (Se) on ischemia/reperfusion (I/R) injury in rat ovaries.

METHODS

Thirty-five female Sprague-Dawley rats were randomly divided into 5 groups (n = 7): sham (S), I/R1, I/R2, Se1, and Se2. In the I/R1 and Se1 groups, 4 hours of ischemia was followed by 6 hours of reperfusion, and in the I/R2 and Se2 groups, 4 hours of ischemia was followed by 12 hours of reperfusion. In the Se groups, 30 minutes before reperfusion, a single dose of 0.2 mg/kg Se was administered intraperitoneally. The ovarian tissue levels of malondialdehyde (MDA) and nitric oxide (NO), and the activities of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) were measured biochemically. Tissue damage to ovarian tissue was scored by histopathologic examination.

RESULTS

The I/R groups had significantly higher MDA levels and lower CAT, SOD, and GPx activities than the sham group (P < .05). Although NO levels were significantly higher in the I/R1 group than in the sham group (P < .05), the NO levels in the I/R2 and sham groups were similar. Selenium pretreatment significantly lowered tissue MDA and NO levels and increased tissue SOD and GPx activities in the Se groups, compared with those in the I/R groups (P < .05). Catalase activities were significantly higher in the Se2 group than in the I/R2 group (P < .05). Catalase activities were higher in the Se1 group than in the I/R1 group, but the difference was not statistically significant. Treatment with Se significantly decreased the ovarian tissue damage scores in the Se2 group compared with those in the I/R2 group (P < .05).

CONCLUSION

Selenium is effective in preventing tissue damage induced by I/R in rat ovaries.