Oxidative stress and protective effect of erythropoietin on methotrexate-induced esophageal damage

Repurposing of erythropoietin as a neuroprotective agent against methotrexate-induced neurotoxicity in rats

BACKGROUND

Methotrexate (MTX) is a cytotoxic drug that can trigger neurotoxicity via enhancing oxidative stress, apoptosis, and inflammation. On the other hand, erythropoietin (EPO) functions as an antioxidant, anti-apoptotic, and anti-inflammatory agent, in addition to its hematopoietic effects.

AIM

The present study was developed to examine the neuroprotective impact of EPO against MTX-provoked neurotoxicity in rats.

METHODS

Chemo fog was elicited in Wistar rats via injection of one dosage of MTX (20 mg/kg, i.p) on the sixth day of the study. EPO was injected at 500 IU/kg/day, i.p for 10 successive days.

RESULTS

MTX triggered memory and learning impairment as evidenced by Morris water maze, passive avoidance, and Y-maze cognitive tests. In addition, MTX induced oxidative stress as evident from the decline in hippocampal Nrf2 and HO-1 levels. MTX brought about apoptosis, as demonstrated by the elevation in p53, caspase-3, and Bax levels, as well as the decrease in Bcl2 levels. MTX also decreased Beclin-1, an autophagy-related marker, and increased P62 expression. In addition, MTX downregulated Sirt-1/AKT/FoxO3a pathway and increased miRNA-34a gene expression. Moreover, MTX increased acetylcholinesterase activity and reduced neurogenesis. EPO administration remarkably counteracted MTX-induced molecular and behavioral disorders in rat hippocampi.

CONCLUSION

Our findings impart preclinical indication for repurposing of EPO as a promising neuroprotective agent through modulating miRNA-34a, autophagy, and the Sirt-1/FoxO3a signaling pathway.

Impact of platelet-rich plasma versus selenium in ameliorating induced toxicity in rat testis: histological, immunohistochemical, and molecular study

This study was conducted on forty adult rats divided into four groups: Group I (control) that is divided into subgroups A, B, and C and Group II (methotrexate (MTX)-treated); the rats were injected intraperitoneally with MTX at a dose of 1 mg/kg/week, for 8 weeks. Group III (MTX-Se co-treated) was injected with MTX like Group II plus an oral administration of selenium at a dose of 10 μg/kg b.w/day, for 8 weeks. Group IV (MTX-PRP co-treated), rats were injected intraperitoneally with MTX like Group II plus platelet-rich plasma (PRP) injection under the scrotum, three times with 2-week intervals (volume-0.1 ml per injection) and euthanized after 8 weeks. Histological, immunohistochemical, and genetic expression using qPCR and western blotting technique were conducted. There was improvement in histological structure of testes in most specimens of Group IV. The latter group revealed a significant decrease in Bax and an increase in Bcl-2. The regeneration of testicular tissue was more observed in Group IV as measured by an increase in mean number of PCNA. Moreover, Group IV revealed an increased genetic level of FSCN3, GCNF, UBQLN3, and DAZL. Both MTX-Se and MTX-PRP have an anti-inflammatory effect as measured by a reduction in NF-κb. The anti-oxidative effect of selenium and PRP was noticed by a decrease in the level of the iNos and an increase in eNos protein and the autophagy marker LC3. PRP has ameliorative effects on induced rat testicular toxicity as evaluated by morphological changes and confirmed by immunohistochemical reactions, genetic expression, and western blotting analyses including oxidative and anti- oxidative markers.

Improvement of Inflammation through Antioxidant Pathway of Gardeniae Fructus 50% EtOH Extract (GE) from Acute Reflux Esophagitis Rats

Gardeniae Fructus 50% EtOH extract (GE) is a traditional herb that has been used to treat a variety of diseases. In this study, we investigate the antioxidant, anti-inflammatory, and antiapoptotic properties of GE on acute reflux-induced esophagitis (RE) model in rats. 2,2′-Azino-bis (3-ethylbenzothiazolin-6-sulfonic acid) (ABTS) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assays were performed to determine the antioxidant activity of GE. GE was given orally at 50 and 100 mg/kg body weight 1h 30 min prior to RE induction. And its effect was assessed in comparison with RE control and normal groups. The administration of the extract of the GE showed remarkable protection of mucosal damage in esophageal tissue, and the histologic observation showed that the gastric lesion was improved. Increased reactive oxygen species (ROS) levels in the serum were diminished by GE treatment. The antioxidative biomarkers including nuclear factor-erythroid 2-related factor 2 (Nrf-2), heme oxygenase-1 (HO-1), superoxide dismutase (SOD), catalase, and glutathione peroxidase (GPX) were significantly increased. GE administration significantly reduced the inflammatory protein expression through MAPK-related signaling pathways and the nuclear factor-kappa B (NF-κB) pathway. These results suggest that GE protects the esophagus mucosal membrane by attenuating oxidative stress and inflammatory response under reflux esophagitis condition through the antioxidant pathway. Therefore, it is suggested that GE may be a potential remedy for the treatment of reflux esophagitis.

Gastroesophageal reflux disease and esophagitis associated with the use of drugs: the modern state of the problem

From the standpoint of evidence - based medicine, the ability of various drugs to induce the development of gastroesophageal reflux disease and esophagitis is considered. Thus, all known drugs can be divided into 3 groups: drugs that have the ability to reduce pressure in the lower esophageal sphincter, for example, β-adrenoreceptor agonists, α-adrenoreceptor antagonists, anticholinergics, calcium channel blockers, nitrates, benzodiazepines (diazepam), estrogen, progesterone, aminophylline (theophylline), tricyclic antidepressants, selective serotonin reuptake inhibitors, glucocorticosteroids; means providing a direct damaging effect on the esophageal mucosa, as well as lowering its resistance reflyuktatu, e.g., bisphosphonates, acetylsalicylic acid / non - steroidal anti - inflammatory agents, anticoagulants, antiplatelet drugs, iron preparations, ascorbic acid, potassium chloride, quinidine, phenytoin, calcium dobesilate, 131I sodium iodide, antibiotics (tetracycline, doxycycline, clindamycin, ciprofloxacin, ornidazole, clindamycin, rifampicin), antitumor agents; drugs that impede gastric emptying: calcium channel blockers, anticholinergics. These data can be used in practice in the choice of treatment tactics, especially in individuals with a diagnosis of gastroesophageal reflux disease or heartburn.

Protective effect of Rhei Rhizoma on reflux esophagitis in rats via Nrf2-mediated inhibition of NF-κB signaling pathway

Background

Rhei Rhizoma has been widely used as a traditional herbal medicine to treat various inflammatory diseases. The present study was conducted to evaluate its anti-inflammatory activity against experimental reflux-induced esophagitis (RE) in SD rats.

Methods

Rhei Rhizoma was administered at 125 or 250 mg/kg body weight per day for 7 days prior to the induction of reflux esophagitis, and its effect was compared with RE control and normal rats.

Results

Rhei Rhizoma administration markedly ameliorated mucosal damage on histological evaluation. The elevated reactive oxygen species in the esophageal tissue of RE control rats decreased with the administration of Rhei Rhizoma. RE control rats exhibited the down-regulation of antioxidant-related proteins, such as nuclear factor-erythroid 2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1) expression levels, in the presence of esophagitis; however, the levels with Rhei Rhizoma treatment were significantly higher than those in RE control rats. Moreover, RE control rats exhibited the up-regulation of protein expressions related to oxidative stress in the presence of esophagitis, but Rhei Rhizoma administration significantly reduced the expression of inflammatory proteins through mitogen-activated protein kinase (MAPK)-related signaling pathways. The protein expressions of inflammatory mediators and cytokines by nuclear factor-kappa B (NF-κB) activation were modulated through blocking the phosphorylation of inhibitor of nuclear factor kappa B (IκB)α.

Conclusion

Our findings support the therapeutic evidence for Rhei Rhizoma ameliorating the development of esophagitis via regulating inflammation through the activation of the antioxidant pathway.

Electronic supplementary material

The online version of this article (doi:10.1186/s12906-015-0974-z) contains supplementary material, which is available to authorized users.

Protective effects of erythropoietin and N-acetylcysteine on methotrexate-induced lung injury in rats

OBJECTIVE

Methotrexate (MTX) is known to have deleterious side effects on lung tissue. We aimed to investigate the effects of erythropoietin (EPO) and N-acetyl-cysteine (NAC) on MTX-induced lung injury in rats.

STUDY DESIGN

Animal experiment.

MATERIAL AND METHODS

Twenty-six female Sprague-Dawley rats were divided into 4 groups. Sham group, 0.3 mL saline; MTX group, 5 mg/kg MTX; EPO group, 5mg/kg MTX and 2000 IU/kg EPO; NAC group, 5 mg/kg MTX and 200 mg/kg NAC were administered once daily for 4 consecutive days. Malondialdehyde (MDA), superoxide dismutase (SOD), catalase (CAT) and inflammation and congestion scores in lung tissues were evaluated.

RESULTS

In MTX group MDA were significantly higher, CAT and SOD were significantly lower than in sham, EPO and NAC groups (p<0.005). In EPO group MDA, CAT, and SOD were higher, but not significant than those in group NAC (p>0.005). In group MTX both scores were significantly higher than in sham (p<0.005). The congestion score of group MTX was significantly higher than those of group EPO and NAC (p<0.005).

CONCLUSION

EPO and NAC have significant preventive effects on MTX-induced lung injury in rats. Decreased antioxidant capacity and increased MDA level may cause the oxidative damage in MTX group. Also, higher antioxidant capacity and lower MDA level may be a response to oxidative stress in EPO and NAC groups.

The Effects of Erythropoietin on Bacterial Translocation and Inflammatory Response in an Experimental Intestinal Obstruction Model in Rats / Uticaj Eritropoetina Na Bakterijsku Translokaciju I Inflamatorni Odgovor U Eksperimentalnom Modelu Intestinalne Opstrukcije Kod Pacova

Background:Intestinal obstruction results in distortion of balance of antiinflammatory cytokines and release of oxidants, and also leads to bacterial translocation, sepsis and multiple organ failure. Asymmetric dimethylarginine is related to multiple organ failure as a new prognostic marker. Erythropoietin reduces the inflammatory response by decreasing the levels of proinflammatory cytokines and cytokine-induced apoptosis. In this study, we aimed to investigate the effectiveness of erythropoietin in reducing the severity of bacterial translocation and inflammatory response after intestinal obstruction and the relation between asymmetric dimethylarginine and inflammatory markers.

Methods:Forty Wistar albino rats (200-250 g) were divided into 4 groups as follows: Group 1 (Sham), only ileocaecal junction dissection; Group 2 (Erythropoietin), ileocaecal junction dissection and 3000 lU/kg erythropoietin subcutaneously; Group 3 (Intestinal Obstruction), complete ileal ligation; Group 4 (Intestinal Obstruction + Erythropoietin), complete ileal ligation and 3000 IU/kg erythropoietin subcutaneously. After 24 hours, the rats were sacrificed by taking blood from the heart for biochemical analyses. Peritoneal swab culture, liver, mesenteric lymph nodes, spleen and ileum were collected for microbiological and histopathological examinations.

Results:Erythropoietin reduced the secretion of inflammatory cytokines, oxidative damage and bacterial translocation, prevented the formation of inflammatory changes in the intestine, liver, spleen and mesenteric lymph nodes,and also significantly prevented the formation of intestinal damage after intestinal obstruction (p<0.05). Conclusions: Asymmetric dimethylarginine levels did not differ between the groups. Erythropoietin may be useful to preserve from intestinal injury and related sepsis in patients with intestinal obstruction. Asymmetric dimethylarginine is not a suitable prognostic marker.