Topiramate ameliorates abdominal aorta cross-clamping induced liver injury in rats

The Promising Effect of Topiramate on Random-Pattern Skin Flap Survival in Rats

BACKGROUND

Partial necrosis of skin flaps following plastic and reconstructive surgeries is one of the major problems in these medical interventions. This study was conducted to evaluate the beneficial effects of topiramate an anti-epileptic agent on ischemic random skin flaps.

MATERIALS AND METHODS

Twenty-four Wistar rats were provided and randomly divided into four experimental groups (control group and low-, intermediate- and high-dose treatment groups). A rat random-pattern skin flap model was performed in all groups, and animals in the low-, intermediate- and high-dose experimental groups were administered topiramate intraperitoneally at doses of 25, 50 and 100 mg/kg, respectively, 1 h before raising the flap and once daily for 7 consecutive days after the initial surgical procedure. Control rats received vehicle according to the same schedule. On postoperative day 7 the flap necrotic area was measured, and tissue samples were stained with hematoxylin and eosin for histological analysis. Furthermore, the oxidative stress in flap tissue was assessed by measuring the activity of superoxide dismutase (SOD), glutathione (GSH) level and the content of malondialdehyde (MDA).

RESULTS

Treating animals with 50 and 100 mg/kg topiramate significantly decreased the necrotic flap areas as compared to the control group. Histological studies demonstrated that in intermediate and high dose topiramate groups the inflammatory cell numbers were attenuated and microvessel development were markedly increased. Furthermore, the MDA contents were significantly reduced and GSH levels were significantly increased in these groups as compared to the control group. However, the SOD activity was increased significantly only in high-dose group as compared to the control group.

CONCLUSIONS

These findings indicated that topiramate in doses of 50 and 100 mg/kg increases random skin flap survival.

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Gastro protecting influence of Topiramate in ethanol produced gastric ulcers in rats

BACKGROUND

Topiramate (TPM), an antiepileptic drug, is also effective against alcohol dependency, a crucial factor in forming gastric ulcers. There is an increased possibility of patients with compromised gastric conditions getting exposed to TPM, but its effect on gastric ulcers is unknown. This study investigates the implication of acute TPM in ethanol-produced gastric ulceration in rats.

MATERIAL AND METHODS

The effect of TPM studied in male 200-225 g Sprague Dawley rats against ethanol-induced gastric ulcers and for gastric secretion and acidity. The factors assessed include gastric secretion and acidity, gastric ulcer score, biochemical and histological changes, NF-kB, and p53 expression. The analysis of data performed by using the Kruskal Wallis test and Dunnett's multiple comparison tests.

RESULTS

TPM pretreatment showed gastroprotective effects. It significantly reduced ethanol-induced increased gastric secretion, acidity, and gastric ulcer index and prevented gastric mucus depletion. The ethanol-induced inflammation and apoptosis were also significantly decreased by reducing the increased gastric myeloperoxidase activity and the expression of NF-kB and p53. TPM pretreatment also reduced the ethanol-induced damage to the gastric histology in rats.

CONCLUSION

TPM exerted a gastro-protective effect against ethanol-induced gastric ulcers mediated by reducing the gastric ulcer index, preventing a decrease of the mucus levels, reduction in inflammation, damage to gastric histology, and a decrease in the enhanced expression of NF-kB and TPM. Further detailed investigations are essential to understand the chronic influence of TPM on gastric ulcers.

The Role of Vaccinium Myrtillus in the Prevention of Renal Injury in an Experimental Model of Ruptured Abdominal Aortic Aneurysm

Objective

To examine the biochemical and histopathological renal effects of ischemia/reperfusion (I/R) injury using a ruptured abdominal aortic aneurysm (RAAA) model in rats and to investigate the potential protective effects of whortleberry (Vaccinium myrtillus).

Methods

Thirty-two male Sprague-Dawley rats were randomly assigned into four groups - control, sham (I/R+glycerol), I/R, and I/R+whortleberry. Midline laparotomy alone was performed in the control group. Atraumatic abdominal clamps were attached under anesthesia to the abdominal aorta beneath the level of the renal artery in the groups subjected to I/R. Sixty-minute reperfusion was established one hour after ischemia. The sham group received five intraperitoneal doses of glycerol five days before I/R. The I/R+whortleberry group received a single intraperitoneal 50 mg/kg dose diluted with saline solution five days before I/R. All animals were finally euthanized by cervical dislocation following 60-min reperfusion.

Results

Increases were observed in malondialdehyde (MDA) levels and tubular necrosis scores (TNS) in thin kidney tissues and in numbers of apoptotic renal tubule cells, together with a decrease in glutathione (GSH) levels, in sham and I/R groups. In contrast, we observed a decrease in MDA levels, TNS, and numbers of apoptotic renal tubule cells, and an increase in GSH levels with whortleberry treatment compared to the I/R group.

Conclusion

Our findings suggest that whortleberry may be effective against acute kidney injury by reducing oxidative stress and apoptosis.

Cardiovascular effects of antiobesity drugs: are the new medicines all the same?

Waiting for a definite answer from well-designed randomized prospective clinical trials, the impact of the new antiobesity drugs -liraglutide, bupropion/naltrexone, phentermine/topiramate and lorcaserin- on cardiovascular outcomes remains uncertain. What has been learned from previous experience with older medicines is that antiobesity drugs may influence cardiovascular health not only causing weight reduction but also through direct actions on the cardiovascular system. Therefore, in the present review, we examine what is known, mainly from preclinical investigations, about the cardiovascular pharmacology of the new antiobesity medicines with the aim of highlighting potential mechanistic differences. We will show that the two active substances of the bupropion/naltrexone combination both exert beneficial and unwanted cardiovascular effects. Indeed, bupropion exerts anti-inflammatory effects but at the same time it does increase heart rate and blood pressure by potentiating catecholaminergic neurotransmission, whereas naltrexone reduces TLR4-dependent inflammation and has potential protective effects in stroke but also impairs cardiac adaption to ischemia and the beneficial opioid protective effects mediated in the endothelium. On the contrary, with the only exception of a small increase in heat rate, liraglutide only exerts favorable cardiovascular effects by protecting myocardium and brain from ischemic damage, improving heart contractility, lowering blood pressure and reducing atherogenesis. As far as the phentermine/topiramate combination is concerned, no direct cardiovascular beneficial effect is expected for phentermine (as this drug is an amphetamine derivative), whereas topiramate may exert cardioprotective and neuroprotective effects in ischemia and anti-inflammatory and antiatherogenic actions. Finally, lorcaserin, a selective 5HT_2C receptor agonist, does not seem to exert significant direct effects on the cardiovascular system though at very high concentrations this drug may also interact with other serotonin receptor subtypes and exert unwanted cardiovascular effects. In conclusion, the final effect of the new antiobesity drugs on cardiovascular outcomes will be a balance between possible (but still unproved) beneficial effects of weight loss and "mixed" weight-independent drug-specific effects. Therefore comparative studies will be required to establish which one of the new medicines is more appropriate in patients with specific cardiovascular diseases.

Topiramate Reduces Aortic Cross-Clamping-Induced Lung Injury in Male Rats

BACKGROUND

Topiramate (TPM) decreases cytokine release and generation of reactive oxygen species (ROS). Cytokine and endothelin-1 (ET-1) secretion and ROS formation play an important role in ischemia-reperfusion (I/R) injury. We aimed to evaluate whether TPM prevents damage occurring in lung tissue during I/R.

MATERIALS AND METHODS

A total of 27 Wistar albino rats were divided into three groups of nine. To the I/R group, two hours of ischemia via infrarenal abdominal aorta cross-ligation and then two hours of reperfusion process were applied. TPM (100 mg/kg/day) orally for seven days was administered in the TPM treatment group. After the last dose of TPM treatment, respectively, two hours of ischemia and two hours of reperfusion were applied in this group.

RESULTS

Tumor necrosis factor-alpha (TNF-α) (p < 0.05), malondialdehyde (MDA) (p < 0.05), myeloperoxidase (MPO) (p < 0.05) and ET-1 (p < 0.05) levels of TPM treatment group's lung tissue were significantly lower than for the I/R group. Caspase-3 and histopathological damage were rather lower than that of the I/R group.

CONCLUSIONS

During I/R, lung damage occurs due to excessive TNF-α and ET-1 release and ROS generation. TPM could well reduce development of lung damage by decreasing cytokine and ET-1 release and levels of ROS produced.

Infliximab Modulates Cisplatin-Induced Hepatotoxicity in Rats

BACKGROUND

Cisplatin (Cis) is one of the most commonly used antineoplastic drugs. It is used as chemotherapy for many solid organ malignancies such as brain, neck, male and female urogenital, vesical and pulmonary cancers. Infliximab blocks tumor necrosis factor alpha (TNF-α). Several studies have reported that infliximab ameliorates cell damage by reducing cytokine levels.

AIMS

We aimed to investigate whether infliximab has a preventive effect against cisplatin-induced hepatotoxicity and whether it has a synergistic effect when combined with Cis.

STUDY DESIGN

Animal experimentation.

METHODS

Male Wistar albino rats were divided in three groups as follows: Cis group, infliximab + Cis (CIN) group and the control group. Each group comprised 10 animals. Animals in the Cis group received an intraperitoneal single-dose injection of Cis (7 mg/kg). In the CIN group, a single dose of infliximab (7 mg/kg) was administered 72 h prior to the Cis injection. After 72 h, a single dose of Cis (7 mg/kg) was administered. All rats were sacrificed five days after Cis injection.

RESULTS

TNF-α levels in the Cis group were significantly higher (345.5±40.0 pg/mg protein) than those of the control (278.7±62.1 pg/mg protein, p=0.003) and CIN groups (239.0±64.2 pg/mg protein, p=0.013). The Cis group was found to have high carbonic anhydrase (CA)-II and low carbamoyl phosphate synthetase-1 (CPS-1) levels. Aspartate transaminase (AST) and alanine transaminase (ALT) levels were lower in the CIN group as compared to the Cis group. Total histological damage was greater in the Cis group as compared to the control and CIN groups.

CONCLUSION

Cis may lead to liver damage by increasing cytokine levels. It may increase oxidative stress-induced tissue damage by increasing carbonic anhydrase II (CA-II) enzyme levels and decreasing CPS-1 enzyme levels. Infliximab decreases Cis-induced hepatic damage by blocking TNF-α and it may also protect against liver damage by regulating CPS-1 and CA-II enzyme levels.

Infliximab Modulates Cisplatin-Induced Hepatotoxicity in Rats

BACKGROUND

Cisplatin (Cis) is one of the most commonly used antineoplastic drugs. It is used as chemotherapy for many solid organ malignancies such as brain, neck, male and female urogenital, vesical and pulmonary cancers. Infliximab blocks tumor necrosis factor alpha (TNF-α). Several studies have reported that infliximab ameliorates cell damage by reducing cytokine levels.

AIMS

We aimed to investigate whether infliximab has a preventive effect against cisplatin-induced hepatotoxicity and whether it has a synergistic effect when combined with Cis.

STUDY DESIGN

Animal experimentation.

METHODS

Male Wistar albino rats were divided in three groups as follows: Cis group, infliximab + Cis (CIN) group and the control group. Each group comprised 10 animals. Animals in the Cis group received an intraperitoneal single-dose injection of Cis (7 mg/kg). In the CIN group, a single dose of infliximab (7 mg/kg) was administered 72 h prior to the Cis injection. After 72 h, a single dose of Cis (7 mg/kg) was administered. All rats were sacrificed five days after Cis injection.

RESULTS

TNF-α levels in the Cis group were significantly higher (345.5±40.0 pg/mg protein) than those of the control (278.7±62.1 pg/mg protein, p=0.003) and CIN groups (239.0±64.2 pg/mg protein, p=0.013). The Cis group was found to have high carbonic anhydrase (CA)-II and low carbamoyl phosphate synthetase-1 (CPS-1) levels. Aspartate transaminase (AST) and alanine transaminase (ALT) levels were lower in the CIN group as compared to the Cis group. Total histological damage was greater in the Cis group as compared to the control and CIN groups.

CONCLUSION

Cis may lead to liver damage by increasing cytokine levels. It may increase oxidative stress-induced tissue damage by increasing carbonic anhydrase II (CA-II) enzyme levels and decreasing CPS-1 enzyme levels. Infliximab decreases Cis-induced hepatic damage by blocking TNF-α and it may also protect against liver damage by regulating CPS-1 and CA-II enzyme levels.

Effect of infliximab on acute hepatic ischemia/reperfusion injury in rats

This study aimed to investigate the hepatoprotective and antioxidant effects of infliximab (IFX) against liver ischemia/reperfusion (I/R) injury in rats. A total of 30 male Wistar albino rats were divided into three groups: sham, I/R, and I/R+IFX. IFX was given at a dose of 3 mg/kg for three days before I/R. Rat livers were subjected to 60 min of ischemia followed by 90 h of reperfusion. Aspartate aminotransferase (AST), alanine aminotransferase (ALT), TNF-α, malondialdehyde (MDA), and glutathione peroxidase (GSH-Px) levels were measured in the serum. The liver was removed to evaluate the histopathologic changes. The I/R group had a significant increase in AST, ALT, MDA, and TNF-α levels, and a decrease in GSH-Px activity compared with the sham group. The use of IFX significantly reduced the ALT, AST, MDA and TNF-α levels and significantly increased GSH-Px activity. IFX attenuated the histopathologic changes. IFX has a protective effect on liver I/R injury. This liver protective effect may be related to antioxidant and anti-TNF-α effects. We propose that, for the relief of liver injury subsequent to transplantation, liver resection, trauma, and shock, tentative treatments can be incorporated with IFX, which is already approved for clinical use.

Is adalimumab protective in ischemia-reperfusion injury in lung?

OBJECTIVES

Increasing cytokines and reactive oxygen species (ROS) during ischemia reperfusion (I-R) leads to the lung damage. Adalimumab (Ada) is a potent tumor necrosis factor-alpha (TNF-α) inhibitor agent. We aimed to evaluate whether Ada would prevent the lung tissue from damage development over the I-R process.

MATERIALS AND METHODS

Twenty seven Wistar albino male rats were divided into three groups (each group had 9 rats). To the control group, only laparotomy procedure was carried out. For I-R group, first infrarenal abdominal aorta was cross-clamped during 2 hr, and then reperfusion was performed for 2 hr. To I-R+Ada group, first a single dose of 50 mg/kg Ada was given intraperitoneally and 5 days later, same I-R procedure was carried out.

RESULTS

Levels of TNF-α, malondialdehyde (MDA), myeloperoxidase (MPO), endothelin-1 (ET-1) and caspase-3 enzyme activity of I-R group were higher than that of both I-R+ Ada [TNF-α (P=0.021), MDA (P=0.029), MPO (P=0.012), ET-1 (P=0.036, caspase-3 (P=0.007), respectively] and control group [TNF-α (P=0.008), MDA (P<0.001), MPO (P=0.001), ET-1 (P<0.001), caspase-3 (P<0.001), respectively]. In I-R group, severe damage was detected by hematoxylin-eosin staining. This damage was found less severe in Ada treatment group.

CONCLUSION

The release of cytokines and ET-1 in a large proportion after I-R injury, and generating of ROS in excessive quantity could cause severe damage in the lung tissue. Ada could be considered as a protective agent for lung tissue during I-R process.

Topiramate attenuates early brain injury following subarachnoid haemorrhage in rats via duplex protection against inflammation and neuronal cell death

Early brain injury (EBI) following aneurysmal subarachnoid haemorrhage (SAH) insults contributes to the poor prognosis and high mortality observed in SAH patients. Topiramate (TPM) is a novel, broad-spectrum, antiepileptic drug with a reported protective effect against several brain injuries. The current study aimed to investigate the potential of TPM for neuroprotection against EBI after SAH and the possible dose-dependency of this effect. An endovascular perforation SAH model was established in rats, and TPM was administered by intraperitoneal injection after surgery at three different doses (20mg/kg, 40mg/kg, and 80mg/kg). The animals' neurological scores and brain water content were evaluated, and ELISA, Western blotting and immunostaining assays were conducted to assess the effect of TPM. The results revealed that TPM lowers the elevated levels of myeloperoxidase and proinflammatory mediators observed after SAH in a dose-related fashion, and the nuclear factor-kappa B (NF-κB) signalling pathway is the target of neuroinflammation regulation. In addition, TPM ameliorated SAH-induced cortical neuronal apoptosis by influencing Bax, Bcl-2 and cleaved caspase-3 protein expression, and the effect of TPM was enhanced in a dose-dependent manner. Various dosages of TPM also upregulated the protein expression of the γ-aminobutyric acid (GABA)-ergic signalling molecules, GABAA receptor (GABAAR) α1, GABAAR γ2, and K(+)-Cl(-) co-transporter 2 (KCC2) together and downregulated Na(+)-K(+)-Cl(-) co-transporter 1 (NKCC1) expression. Thus, TPM may be an effective neuroprotectant in EBI after SAH by regulating neuroinflammation and neuronal cell death.