Protective effects of montelukast on ischemia-reperfusion injury in rat ovaries subjected to torsion and detorsion: biochemical and histopathologic evaluation

Montelukast, an available and safe anti-asthmatic drug, prevents maladaptive remodelling and maintains cardiac functionality following myocardial infarction

Preclinical and clinical data indicate that the 5-lipoxygenase pathway becomes activated in cardiovascular diseases suggesting an important role of CysLTs in atherosclerosis and in its ischemic complications. This study aims to investigate the effects of montelukast, a CysLTR-1 antagonist, in a mouse model of myocardial infarction (MI). C57BL/6N female mice were subjected to coronary artery ligation and received montelukast (10 mg/kg/day, intraperitoneal) or vehicle. Montelukast exerted beneficial effects in the infarcted area, decreasing mRNA expression of inflammatory genes, such Il1β and Ccl2 (p < 0.05), at 48 h after MI, and reducing infarct size and preventing ischemic wall thinning (p < 0.05) at 4 weeks. Furthermore, montelukast counteracted maladaptive remodelling of whole heart. Indeed, montelukast reduced LV mass (p < 0.05) and remote wall thickening (p < 0.05), and improved cardiac pumping function, as evidenced by increased global ejection fraction (p < 0.01), and regional contractility in infarcted (p < 0.05) and in remote non-infarcted (p < 0.05) myocardium. Finally, montelukast prevented cardiomyocytes hypertrophy (p < 0.05) in remote myocardium, reducing the phosphorylation of GSK3β, a regulator of hypertrophic pathway (p < 0.05). Our data strongly demonstrate the ability of montelukast to contrast the MI-induced maladaptive conditions, thus sustaining cardiac contractility. The results provide evidences for montelukast "repurposing" in cardiovascular diseases and in particular in myocardial infarction.

Protective effects of esculetin against ovary ischemia-reperfusion injury model in rats

AIMS

Ovarian ischemia-reperfusion (I/R) injury is a phenomenon that necessitates urgent intervention, which occurs as a result of ovarian torsion, and it is frequently seen in young women. A large amount of free radical and oxidative damage as a result of I/R plays a role in the cause of the incident. Antioxidant agents are thought to be beneficial in preventing this damage, and the potential protective effects of esculetin, which had not been tested previously, were investigated in this study.

STUDY DESIGN

The rats in the study were divided into five groups at random: control, sham, esculetin, I/R, and treatment. Oxidative stress parameters, proinflammatory cytokines, nuclear factor erythroid 2-related factor 2 (Nrf-2)/nuclear factor-kβ (NF-κβ) pathway, and histopathological analyses were evaluated at the end of the study.

KEY FINDINGS

After I/R, malondialdehyde levels, proinflammatory cytokines, tumor necrosis factor-α and interleukin-1β levels and NF-κβ expressions were increased, Nrf-2 expression and glutathione level decreased and the histopathologic picture deteriorated. However, as a result of the esculetin treatment, ameliorative effects in the aforementioned parameters were determined, and it was ensured that they returned to normal levels.

CONCLUSION

According to these findings, esculetin has protective effects on I/R damage by lowering lipid peroxidation and having antioxidant and anti-inflammatory properties.

SIGNIFICANCE

Our results proved the protective effect of esculetin against ovarian IR injury in rats and this may be attributed to Nrf-2/NF-κβ axis which showed antioxidant and anti-inflammatory effects. Therefore, esculetin can be used in the future for preventive effects to ovarian IR injury.

Montelukast sodium protects against focal cerebral ischemic injury by regulating inflammatory reaction via promoting microglia polarization

BACKGROUND

Neuroinflammation plays an important role in brain injury and repair. Regulation of post-stroke inflammation may be a reasonable strategy to treat ischemic stroke. The present study demonstrates that montelukast sodium protected brain tissue by regulating the post-stroke inflammatory reaction.

METHODS

Adult male mice underwent distal occlusion of the middle cerebral artery (d-MCAO) surgery, followed by intraperitoneal injection of montelukast sodium or equivalent saline, from day 0-7 after the operation. On the 7th day, Rotarod and adhesive-removal test were performed. M AP2 staining, and Iba1, CD206, and CD16/32 co staining were performed. BV2 microglial cell lines were co-cultured with different concentrations of montelukast sodium with or without lipopolysaccharide (LPS). Real-time polymerase chain reaction (rt-PCR) and enzyme linked immunosorbent assay (ELISA) were used to detect the mRNA expression of M1 and M2 phenotypic microglia markers and the release of cytokines representing from different phenotypes of microglia cells.

RESULTS

Montelukast sodium prolonged the time that d-MCAO mice remained on the rotating bar, shortened the time to remove the sticker on the opposite claw, and reduced the infarct volume, promoting the transformation of microglial cells/macrophages around the infarct to the M2 phenotype. Montelukast sodium increased the mRNA expression of Arg-1, CD206, TGF-β, and IL-10 in BV2 microglial cell lines stimulated by LPS, while decreased the expression of iNOS, TNF-α, and CD16/32.

CONCLUSION

Montelukast sodium can protect against focal cerebral ischemic injury by regulating inflammatory reaction via promoting microglia polarization.

Atorvastatin-mediated downregulation of VCAM-1 and XO/UA/caspase 3 signaling averts oxidative damage and apoptosis induced by ovarian ischaemia/reperfusion injury

Background

Oxidative damage is critical in the pathogenesis of ovarian ischaemia/reperfusion (I/R) injury, and statins have been reported to exert antioxidant activity. However, the role of VCAM-1 and xanthine oxidase (XO)/uric acid (UA) in ovarian I/R injury is not known. Also, whether or not atorvastatin exerts antioxidant activity like other statins is unclear.

Objectives

This study investigated the involvement of VCAM-1 and XO/UA in ovarian I/R injury and the likely protective role of atorvastatin.

Methods

Forty female Wistar rats were randomized into sham-operated, ischaemia, ischaemia/reperfusion (I/R), ischaemia and atorvastatin, and I/R and atorvastatin.

Results

In comparison with the sham-operated group, atorvastatin blunted ischaemia and I/R-induced distortion of ovarian histoarchitecture and follicular degeneration. Also, atorvastatin alleviated ischaemia and I/R-induced rise in XO, UA, and malondialdehyde, which was accompanied by inhibition of ischaemia and I/R-induced reductions in reduced glutathione level, enzymatic antioxidant activities and increase in myeloperoxidase activity and TNF-α and IL-6 levels by atorvastatin treatment. Additionally, atorvastatin blocked ischaemia and I/R-induced increase in VCAM-1 expression, caspase 3 activity, 8-hydroxydeoxyguanosine level and ovarian DNA fragmentation index.

Conclusion

For the first time, this study revealed that atorvastatin-mediated downregulation of VCAM-1 and XO/UA/caspase 3 signaling averts oxidative injury, inflammation, and apoptosis induced by ovarian ischaemia/reperfusion injury.

The effect of medical ozone therapy in addition to ovarian detorsion in ischemia reperfusion model

This study aimed to investigate the protective effect of ozone therapy on ovarian reserve, number of ovarian follicles, ovarian morphology in a rat ischaemia reperfusion (IR) injury model. Twenty-four, Wistar Hannover rats were included. The rats were divided into three groups as control, detorsion-only, and ozone therapy + detorsion groups. There was a statistically significant difference in the follicular damage and inflammation scores between the study groups (p = .019, p = .002, respectively). The highest AMH decrease was observed in the detorsion-only group (p = .012). The total damage score was higher in the detorsion-only group than the ozone therapy + detorsion group. Preantral, small and large antral follicle numbers were less in the detorsion-only group than the ozone therapy + detorsion group. The highest postoperative day 7 TAS level was in the ozone therapy + detorsion group. TOS levels did not differ significantly between the study groups. The combination of the ozone therapy with ovarian detorsion is more effective in protecting the ovarian reserve than ovarian detorsion-only.Impact StatementWhat is already known on this subject? Adnexal torsion is a common gynecological emergency in reproductive-age women. The recommended management is the detorsion of the adnexal pedicle in patients with fertility desire.What do the results of this study add? The combination of the medical ozone therapy with conventional surgical ovarian detorsion is more effective in the protection of the ovarian reserve compared to surgical ovarian detorsion.What are the implications of these findings for clinical practice and/or further research? This study speculates that medical ozone therapy in addition to conventional surgical ovarian detorsion could preserve ovarian reserve and function if confirmed in further clinical studies.

Leukotriene receptor antagonism with montelukast as a possible therapeutic for venous thromboembolism prophylaxis: An observational study

BACKGROUND

Arachidonic acid (AA), which is metabolized via the cyclooxygenase (COX) and the lipoxygenase (LOX) pathways, was found to be associated with venous thromboembolism (VTE). Metabolites of the LOX pathway include cysteinyl (Cys) Leukotrienes (LT), potent proinflammatory mediators, which have also been implicated in cardiovascular disease.

OBJECTIVE

The purpose of this study was to examine if cysteinyl leukotriene receptor blockade by montelukast, lowers the risk of VTE.

METHODS

We conducted a retrospective cohort study examining VTE risk among COPD patients from the United States Department of Veterans Affairs. We use propensity score matching and Cox survival models to estimate the hazard ratio comparing montelukast exposure to non-exposure. Montelukast exposure was associated with a 15.9% reduction in risk of VTE compared to those unexposed (HR= 0.841; 95% CI= (0.758-0.934)).

CONCLUSION

The results of this study demonstrate that targeting LTs might be beneficial for VTE prophylaxis using the clinically available LT inhibitor, montelukast. Importantly, further research on LTs is warranted to fully understand and validate this relationship.

The effect of intratesticular dexpanthenol on experimentally-induced testicular ischaemia/reperfusion injury

INTRODUCTION

Testis torsion is a urological emergency and a serious situation that may cause testis atrophy, testicular dysfunction and infertility due to ischaemia/reperfusion(I/R) injury even with early intervention.

OBJECTIVE

To assess the protective effect of dexpanthenol administered intratesticular after detorsion against testis I/R injury.

STUDY DESIGN

Twenty-seven rats were randomly divided into 3 groups containing 9 rats each. The 1st group comprised the sham group with no procedure performed. The 2nd group had only torsion applied, while the 3rd group had torsion + dexpanthenol applied. Rats had 720° clockwise rotation applied to the left testis. After 2 h of ischaemia, testes were de-torsioned and the dexpanthenol group had 500 mg/kg dexpanthenol administered intratesticular after detorsion. After 4 h of reperfusion, rats had blood samples taken and orchiectomy was performed for histologic assessment.

RESULTS

A significant difference was detected in all parameters [necrosis(p:<0.001), Cosentino grade (p < 0.001), congestion (p:0.005), fibrosis (p:<0.001), interstitial oedema (p:0.017), JTBS score (p:<0.001), apoptosis (p < 0.001) and testosterone levels (p:0.006)] when the sham, torsion, and torsion + dexpanthenol groups were compared. Significant differences were observed for fibrosis (p:0.010), Cosentino score (p < 0.001), JTBS score (p:<0.001), apoptosis (p:0.001) and total testosterone levels (p:0.013) when torsion and torsion + dexpanthenol groups were compared. The torsion + dexpanthenol group was identified to have more preservation of testis function observed histologically and hormonally compared to the torsion group.

DISCUSSION

Dexpanthenol is used in many areas due to both epithelizing and antioxidant effects and lack of clear side effects. In spite of use of many chemical and biological agents to protect against testis I/R injury, none have entered routine use. This study showed that dexpanthenol, which can be easily injected intratesticular during detorsion surgery, has protective effect against histological and functional injury that may develop linked to testis I/R injury. The main limitations of the study are short duration of follow-up due to being a rat experiment and lack of comparison of lipid peroxidation products.

CONCLUSION

This study identified that dexpanthenol with clinically easy use by intratesticular injection after detorsion during surgery had a protective effect against histological and functional injury that will develop linked to I/R injury in the testis.

Influence of Systemic Administration of Coq10 Nanoparticles on Ischemia-Reperfusion Injury on Ovaries in Rat

Using a rat ovary model, effects of COQ10 nanoparticles (NCOQ10) were studied on ischemia-reperfusion injury. In the present experimental study, following randomization of thirty healthy female Wistar rats ∼250 g, the animals were subjected to five experimental groups (n = 6): group SHAM : only laparotomy was performed, group IS: only a 3-hour ischemia was performed, group IS/REP: the procedure included a 3-hour ischemia followed by a 3-hour reperfusion, and 50 µL soybean oil (solvent of NCOQ10) was administered 30 min before cessation of reperfusion, group IS/NCOQ10: the procedure included a 3-hour ischemia only and 50 µL (0.3 mmol/lit/IP) of NCOQ10 30 min before cessation of ischemia, and group IS/REP/NCOQ10: the procedure included a 3-hour ischemia, a 3-hour reperfusion, and 20 µL (0.3 mmol/lit) of NCOQ10 30 min before cessation of ischemia. Significantly amended development of ischemia/reperfusion tissue injury was observed in animals treated with NCOQ10 compared to those of other groups (P=0.001). Mean values of biochemical indices were significantly higher than those observed for other groups (P=0.001). Significantly lower values of MDA were observed in IS/REP/NCOQ10 animals compared to those of other groups (P=0.001).Where ovarian tissue is exposed to ischemia, intraperitoneal administration of NCOQ10 could bear clinical benefits in diminishing ischemia-reperfusion injury.

Montelukast Drug May Improve COVID-19 Prognosis: A Review of Evidence

With the lack of effective therapy, chemoprevention and vaccination, focusing on the immediate repurposing of existing drugs gives hope of curbing the pandemic. Interestingly, montelukast, a drug usually used in asthma, may be proposed as a potential adjuvant therapy in COVID-19. The aim of the present article was to review the properties of montelukast that could be beneficial in COVID-19. Ten experimentally supported properties were retrieved, either related to SARS-CoV-2 (antiviral properties, prevention of endotheliitis and of neurological disorders linked to SARS-CoV-2), and/or related to the host (improvement of atherogenic vascular inflammation, limitation of the ischemia/reperfusion phenomenon, improvement of respiratory symptoms), and/or related to serious COVID-19 outcomes (limitation of the cytokine storm, mitigation of acute respiratory distress syndrome), and/or related to tissue sequelae (antioxidant properties, anti-fibrosis effects). Based on gathered theoretical evidence, we argue that montelukast should be further tested to prevent and treat COVID-19 outcomes.

Protective Effect of Lycopene against Reperfusion Injury in Rats with Ovarian Torsion: A Biochemical and Histopathological Evaluation

Objective  The aim of our study was to evaluate the effect of two different doses of lycopene, an antioxidant, on experimentally induced ovarian ischemia/reperfusion (IR) injury in rat model.

Materials and Methods  Twenty-four female rats were randomly divided into four groups: sham operation (group 1), 3-hour ischemia, 3-hour reperfusion (IR) (group 2), and IR + 100 mg/kg lycopene (PO) (group 3), IR + 200 mg/kg of lycopene (group 4). The rats’ superoxide dismutase (SOD), myeloperoxidase (MPO) activities, malondialdehyde (MDA), and glutathione (GSH) levels were calculated. Ovarian tissue damage was assessed using a histopathological scoring system.

Results  Serum parameter levels and histological scores showed that treatment with lycopene may be conservative approach to prevent IR injury after the ovarian detorsion procedure.The improvement with lycopene was higher at 200 mg than at 100 mg. The MPO and MDA values were significantly lower in groups 3 and 4 as compared with group 2 ( p < 0.05), whereas the MPO and MDA values were lower in group 4 as compared with group 3.The SOD and GSH values were significantly higher in groups 3 and 4 as compared with group 2 ( p < 0.05), whereas the SOD and GSH values were higher in group 4 as compared with group 3.Tissue damage scores were elevated in the IR group compared with the sham group, but the treatment with different lycopene doses after reperfusion improved the histopathological tissue damage scores.

Conclusion  The results showed that lycopene treatment reduced ovarian IR damage. Antioxidant activity was found to increase in a dose-dependent manner. Lycopene treatment may be conservative approach for ovarian torsion patients after the detorsion procedure to prevent IR damage.

Effect of metformin and detorsion treatment on serum anti-Müllerian hormonelevels and ovarian histopathology in a rat ovarian torsion model

Background/aim

Adnexal torsion is a common gynaecological emergency, and considered to be a problem mostly in reproductive-age women. To evaluatethe effect of metformin and detorsion treatment on reducing ovarian reserve in an ovarian torsion model.

Materials and methods

Twenty-four nonpregnant, Wistar Hannover rats were included in the study. Animals were divided into 3 groups: the control group, the detorsion only group, and the metformin + detorsion group. The first group received only laparotomy. In the second group, ovaries were fixed to the abdominal wall after performing 360° ovarian torsion, followed by detorsion after a 3-h period of ischemia. The third group underwent the same torsion and detorsion procedures as the second group, and received 50 mg/kg metformin by gavage for 14 days. Ovarian damage scores, follicle counts, and AMH levels were evaluated.

Results

The total damage score was significantly increased in the detorsion only group compared to the metformin+detorsion and control groups. Pre-operative/post-operative AMH decreases were statistically significant in negative direction in the detorsion only group when compared to the metformin+detorsion and control groups (P = 0.001).

Conclusion

Metformin+detorsion treatment may be effective in protecting the ovarian reserve after ovarian torsion.

Montelukast for Medical Delay in Flap Surgery

BACKGROUND

Delay phenomenon can be used for better blood supply of the flap in plastic surgery. Effects of Montelukast have been observed to reduce ischemia/reperfusion injury in various organs due to angiogenic and anti-oxidant effects. The present study aimed to determine the role of Montelukast as medical delay of the flaps.

METHODS

In this experimental study, 42 Wistar rats were divided into 3 equal groups. These groups were Surgical Delay Group (SDG), Medical Delay Group (MDG) and Control Group (CG). In SDG, 8×3 cm rectangular randomized random skin flap was first surgically delayed at rats' back. The MDG received 10 mg/kg oral Montelukast via orogastric tube for 5 days as medical delay. In MDG and SDG flap, harvesting was undertaken after a delayed period, but there was not any delayed period in CG. After delayed period, a segment of the skin flap was biopsied for assessing angiogenesis. After 14th days, the photos were taken and the size of the necrotic area of the flap was measured.

RESULTS

A significant difference was observed between the mean survival and angiogenesis (p=0.002). The same performance was reported between MDG and SDG, which were alike regarding survival and angiogenesis (p>0.05); while there was a significant difference between the control and surgical groups, as well as control and medical groups (p<0.05). Finally, the inflammation showed no significant difference (p>0.05).

CONCLUSION

Regarding positive effects of Montelukast on survival and angiogenesis, it is recommended to be used as a medication for larger studies.

An investigation of the effects of metformin on ovarian ischemia-reperfusion injury in rats

Damage to the ovaries or tissue torsion can significantly reduce the ovarian reserve and thus cause severe gynecological and hormonal deficiencies. The discovery of new agents is always needed in the treatment of this condition. Metformin (MET) has been shown to be beneficial in attenuating ovarian ischemia-reperfusion injury. Fifty-six female Sprague Dawley rats were divided into seven groups. Group 1 represented the control group (C), Group 2, the ischemia group (I), and Group 3, the ischemia/reperfusion group (I/R). Group 4, the ischemia (I)+250 group, and Group 5, the ischemia (I)+500 group, received 250 mg/kg and 500 mg/kg MET, respectively. Group 6, the ischemia/reperfusion (I/R)+250 group, and Group 7, the ischemia/reperfusion (I/R)+500 group, received 250 mg/kg and 500 mg/kg MET, respectively. Tissue malondialdehyde (MDA), glutathione (GSH), and tumor necrosis factor-alpha (TNF-α) levels in ovarian tissue increased following I/R, while estradiol (E₂) levels decreased. Moreover, infiltration and diffuse edematous areas were observed in addition to diffuse vascular congestion and hemorrhage findings. Caspase-3 and nuclear factor kappa B (NF-κβ) expression levels also increased. MDA and TNF-α concentrations decreased in the MET treatment groups, while GSH and E₂ levels increased. The findings showed that I/R causes ovarian damage through the induction of oxidative stress, inflammation, and apoptosis. However, MET application was effective in preventing damage in ovarian tissue by reducing levels of reactive oxygen species, proinflammatory cytokines, caspase-3 and NF-κβ.

The propolis and boric acid can be highly suitable, alone/or as a combinatory approach on ovary ischemia-reperfusion injury

PURPOSE

Ovarian ischemia-reperfusion (IR) damage continues to be a serious infertility problem. The oxidative stress plays central role in the development of IR injuries. Activation of antioxidants decreases IR injuries; however, the efficacy of antioxidant agents remains controversial. Unfortunately, there has been no evidence for medicinal use of boric acid (BA) and propolis (Prop) on ovarian IR injury on rats so far. This study will provide to reveal the potential applications of the Prop and BA in ovarian IR therapy.

METHODS

The Sprague-Dawley rats were randomized into five groups: I-control, II-IR, 3 h of ischemia and 3 h of reperfusion, III and IV-a signal dose of oral BA (7 mg/kg) and Prop (100 mg/kg) alone 1 h before induction of IR, V-Prop and BA together 1 h before induction of IR. SOD (superoxide dismutase), CAT (catalase), GSH (glutathione), MPO (myeloperoxidase), MDA (malondialdehyde), and IL-6 (interleukin-6) levels were quantified by ELISA and the TNF-α (tumor necrosis factor-α), 8-OHdG (8-hydroxylo-2'-deoxyguanosin) and Caspase-3 expressions were performed by immunohistochemical analyses.

RESULTS

BA and Prop pretreatment significantly reduced MPO, MDA, and IL-6 levels and pathologic score in IR rats, with no effects in control group. These agents used in therapy also decreased TNF-α, 8-OHdG and Caspase-3 protein expressions increased by IR. Furthermore, BA and Prop combination showed significant ameliorative effects on ovary injury caused by IR through acting as an antioxidant, anti-inflammatory and antiapoptotic agent.

CONCLUSION

BA and Prop alone and especially in combination could be developed as therapeutic agents against ovary IR injury.

Montelukast inhibits inflammatory response in rheumatoid arthritis fibroblast-like synoviocytes

Montelukast, a potent selective antagonist of cysteinyl leukotriene (cysLT) receptors, has displayed its important anti-oxidative and anti-inflammatory effects in various tissues and organs. Rheumatoid arthritis (RA) is an immune disease defined by hyperplastic synovitis and joint destruction. Fibroblast-like synoviocytes in RA (RA-FLSs) are the main cell component of the hyperplastic synovium. Whether montelukast can protect against the inflammatory milieu of RA remains unclear. Here, it is shown that cysLT1R is present in FLSs and unregulated in RA-FLSs. Montelukast has an inhibitory effect on the inflammatory microenvironment of RA by decreasing the secretion of IL-6, IL-8, MMP-3 and MMP-13 in FLSs induced by IL-1β. Notably, treatment with montelukast attenuated IL-1β-induced phosphorylation of IκBα, IκBα degradation, nuclear translocation of p65 and NF-κB activity to express a luciferase reporter gene in FLSs. The findings of the current study provide evidence for a novel therapeutic strategy for RA using montelukast.

Interaperitoneal Administration of Αlpha-Tocopherol Loaded Nanoparticles Improves Ischemia-Reperfusion Injury in Rat Ovaries Torsion and Detorsion Model

Objective:

To investigate effects of intraperitoneally administration of α-tocopherol loaded nanoparticles (TNP) on ischemia-reperfusion injury in ovaries.

Methods:

Thirty-five healthy female Wistar rats ~250g were randomized into seven experimental groups (n = 5): Group SHAM: The rats underwent only laparotomy. Group Ischemia: A 3- hour ischemia only. Group I/R: A 3-hour ischemia and a 3-hour reperfusion. Group I/T: A 3-hour ischemia only and 100 mg/kg intraperitoneal administration (IP) of α-tocopherol 2.5 hours after induction of ischemia. Group I/R/T: A 3-hour ischemia, a 3-hour reperfusion and 100 mg/kg IP of α-tocopherol 2.5 hours after induction of ischemia. Group I/TNP: A 3-hour ischemia only and 1 mg/kg IP of TNP 2.5 hours after induction of ischemia. Group I/R/TNP: A 3-hour ischemia, a 3-hour reperfusion and 1 mg/kg IP of TNP 2.5 hours after induction of ischemia.  

Results:

Animals treated with αTNP showed significantly ameliorated development of ischemia and reperfusion tissue injury compared to those of other groups (p=0.001). The significant higher values of SOD, tGSH, GPO, GSHRd and GST were observed in I/R/NC animals compared to those of other groups (p=0.001). Damage indicators (NOS, MDA, MPO and DNA damage level) were significantly lower in I/R/NC animal compared to those of other groups (p=0.001).

Conclusion:

Intraperitoneal administration of TNP could be helpful in minimizing ischemia-reperfusion injury in ovarian tissue exposed to ischemia.

Zileuton alleviates acute cisplatin nephrotoxicity: Inhibition of lipoxygenase pathway favorably modulates the renal oxidative/inflammatory/caspase-3 axis

OBJECTIVE

The current study investigated for the first time the possible beneficial effect of zileuton, a selective 5-lipoxygenase inhibitor (5-LOX), against cisplatin-induced acute renal failure.

METHODOLOGY

Male Sprague-Dawley rats (180-200 g) were administered cisplatin once (5 mg/kg, i.p.) alone or combined with oral zileuton (10 mg/kg, given twice; 1 h before and 12 h after cisplatin).

RESULTS

Compared with control rats, acute cisplatin administration caused significant increases of BUN (33.76 ± 7.74 vs 61.88 ± 11.35 mg/dl), serum creatinine (0.61 ± 0.21 vs 1.56 ± 0.28 mg/dl), renal levels of MDA (6.40 ± 1.04 vs 20.52 ± 2.18 nmol/g tissue), NOx (3.45 ± 1.20 vs 17.70 ± 2.27 nmol/g tissue), TNF-α (6.71 ± 0.66 vs 23.71 ± 3.41 pg/g tissue), MPO (0.87 ± 0.09 vs 3.12 ± 0.41 U/mg tissue protein) and renal caspase-3 activity (2.81 ± 0.37 vs 12.70 ± 2.94 U/mg tissue protein). Whereas, total SOD activity (1.99 ± 0.53 vs 0.79 ± 0.06 U/mg tissue protein) and IL-10 (110.98 ± 19.70 vs 62.34 ± 14.42 pg/g tissue) were significantly decreased. Cisplatin-induced nephrotoxicity was further confirmed histopathologically (tubular necrosis, cystic dilatation of renal tubules, vacuolar degeneration of renal tubular epithelium with perivascular oedema, and interstitial fibrosis). These changes were accompanied by alteration in 5-LOX pathway manifested as elevated renal levels of 5-LOX, LTD4 and LTB4. Simultaneous administration of zileuton to the cisplatin-treated rats reversed the deleterious renal insults and restored the measured parameters near to control values.

CONCLUSIONS

These data establish the first experimental evidence that zileuton abrogates cisplatin nephrotoxicity in rats probably via the inhibition of detrimental actions of 5-LOX products, thus favorably affecting renal oxidative/inflammatory/caspase-3 axis. Based on current findings, the therapeutic prospect of zileuton for this purpose is recommended.

Protective effects of tempol in an experimental ovarian ischemia-reperfusion injury model in female Wistar albino rats

The aim of this study was to investigate the antioxidant effects of tempol on ovarian ischemia-reperfusion (I/R) injury in rats. Forty female Wistar albino rats were randomly divided into 5 groups: Group I, sham; Group II, ischemia (I); Group III, I/R; Group IV, I/R + tempol 30 mg/kg i.p; Group V, I/R + tempol 50 mg/kg i.p. Oxidative stress index (OSI) was significantly higher in the ischemia group and the I/R group than in the sham group. Catalase levels were significantly lower in the I/R group than in the I/R + tempol 30 mg/kg i.p. and the I/R + tempol 50 mg/kg i.p. groups. Glutathione peroxidase levels were lower in the I/R group than in the I/R + tempol 30 mg/kg i.p. and the I/R + tempol 50 mg/kg i.p. groups. MDA levels were significantly lower in the I/R + tempol 30 mg/kg i.p. group and the I/R + tempol 50 mg/kg i.p. group than in the I/R group. The levels of the histopathological parameters were significantly decreased in the I/R + tempol 50 mg/kg i.p. group compared with the I/R group. Tempol can be used for reducing ovarian I/R injury.

The leukotriene receptor antagonist montelukast and its possible role in the cardiovascular field

BACKGROUND

Cysteinyl leukotrienes (LTC4, LTD4, and LTE4) are pro-inflammatory mediators of the 5-lipooxygenase (5-LO) pathway, that play an important role in bronchoconstriction, but can also enhance endothelial cell permeability and myocardial contractility, and are involved in many other inflammatory conditions. In the late 1990s, leukotriene receptor antagonists (LTRAs) were introduced in therapy for asthma and later on, approved for the relief of the symptoms of allergic rhinitis, chronic obstructive pulmonary disease, and urticaria. In addition, it has been shown that LTRAs may have a potential role in preventing atherosclerosis progression.

PURPOSE

The aims of this short review are to delineate the potential cardiovascular protective role of a LTRA, montelukast, beyond its traditional use, and to foster the design of appropriate clinical trials to test this hypothesis.

RESULTS AND CONCLUSIONS

What it is known about leukotriene receptor antagonists? •Leukotriene receptor antagonist, such as montelukast and zafirlukast, is used in asthma, COPD, and allergic rhinitis. • Montelukast is the most prescribed CysLT₁ antagonist used in asthmatic patients. • Different in vivo animal studies have shown that leukotriene receptor antagonists can prevent the atherosclerosis progression, and have a protective role after cerebral ischemia. What we still need to know? • Today, there is a need for conducting clinical trials to assess the role of montelukast in reducing cardiovascular risk and to further understand the mechanism of action behind this effect.

Protective effects of intraperitoneal administration of nimodipine on ischemia-reperfusion injury in ovaries: Histological and biochemical assessments in a rat model

PURPOSE

Ovarian torsion must be diagnosed and treated as much early as possible. The aim of the present study was to investigate effects of intraperitoneal administration of nimodipine on ischemia-reperfusion injury in ovaries.

METHODS

Thirty healthy male Wistar rats weighing approximately 250g were randomized into six experimental groups (n=5): Group Sham: The rats underwent only laparotomy. Group I: A 3-h ischemia only. Group I/R: A 3-h ischemia and a 3-h reperfusion. Group I/Nimodipine: A 3-h ischemia only and 1mg/kg intraperitoneal administration of nimodipine 2.5h after induction of ischemia. Group I/R/Nimodipine: A 3-h ischemia, a 3-h reperfusion and 1mg/kg intraperitoneal administration of nimodipine 2.5h after induction of ischemia.

RESULTS

Nimodipine treated animals showed significantly ameliorated development of ischemia and reperfusion tissue injury compared to those of other groups (P<0.05). The significant higher values of SOD, tGSH, GPO, GSHRd and GST were observed in I/R/Nimodipine animals compared to those of other groups (P<0.05). The damage indicators (NOS, MDA, MPO and DNA damage level) were significantly lower in I/R/Nimodipine animal compared to those of other groups (P<0.05).

CONCLUSIONS

Intraperitoneal administration of nimodipine could be helpful in minimizing ischemia-reperfusion injury in ovarian tissue exposed to ischemia.

Protection from ischemia by preconditioning, postconditioning, and combined treatment in rabbit testicular ischemia reperfusion injury

This study aimed to investigate the protection of ischemic preconditioning (IPreC), ischemic postconditioning (IPostC) and combined treatment on ischemia reperfusion injury (IRI) of testis. A rabbit testicular ischemia reperfusion (IR) model was established with determining of rabbit serum testosterone, nitric oxide (NO), malondialdehyde (MDA), protein carbonyl (PC), superoxide dismutase (SOD), myeloperoxidase (MPO), glutathione peroxidase (GSH-Px), and tissues pathology. After IR, the NO, MDA, PC, SOD, MPO, and GSH-Px expression significantly increased in torsive testis, and significantly decreased after IPreC, IPostC, and combined treatment in torsive testis when compared to contralateral testis. In torsive testis, testicular tissues was severely damaged with spermatogenic cells disappearing, and were filled with light eosin edema liquid. Cell apoptosis index significantly increased, and the ratio of Bcl-2/Bax significantly decreased. After IPreC, IPostC, and combined treatment, testicular tissues were restored to normal, cell apoptosis index significantly decreased, and the ratio of Bcl-2/Bax significantly increased. It indicates that IPreC, IPostC, and combined treatment has an obvious protective effect on testicular IRI, by decreasing the oxidative stress index and cell apoptosis, provides a significant reference for the treatment of testicular torsion induced infertility, and exhibits a great value in clinical applications.

Aliskiren - a promising strategy for ovarian ischemia/reperfusion injury protection in rats via RAAS

The aim of this study was to evaluate the effects of aliskiren, direct renin inhibitor, as an antioxidant and tissue protective agent and evaluate the molecular, biochemical, and histopathological changes in experimental ischemia and ischemia/reperfusion injury in rat ovaries. Forty-eight female rats were randomly divided into eight groups: in Group 1, only sham operation was performed. Group 2 received 100 mg/kg aliskiren and sham operated. In Group 3, 3 h-period of bilateral ovarian ischemia was applied. Group 4 received a 3-h period of ischemia followed by 3 h of reperfusion. Groups 5 and 6 received 50 and 100 mg/kg, respectively, of aliskiren and bilateral ovarian ischemia was applied (after a 3-h period of ischemia, both ovaries were surgically removed). To Groups 7 and 8, 50 and 100 mg/kg of aliskiren were administered, respectively, and the induction of ischemia was performed. At the end of a 3-h period of ischemia, bilateral vascular clips were removed, and 3 h of reperfusion continued. After the experiments, IL-1β, IL-6, TNF-α, and iNOS mRNA expressions and SOD, GSH, MDA, renin, and angiotensin-II levels were determined and histopathological changes were examined in rat ovaries. Aliskiren treatment normalized excessive changes in cytokine and oxidative stress markers in both ischemia and ischemia/reperfusion injury. Histopathologically, treatment with aliskiren ameliorated the development of ischemia and/or ischemia/reperfusion tissue injury. This study concluded that aliskiren treatment is effective in reversing ischemia and/or ischemia/reperfusion induced ovary damage via the improvement of oxidative stress, reduction of inflammation, and suppression of the renin-angiotensin aldosterone system.

The Protective Effects of Alpha-Lipoic Acid and Coenzyme Q10 Combination on Ovarian Ischemia-Reperfusion Injury: An Experimental Study

Objective. This study aims to evaluate whether alpha-lipoic acid and/or coenzyme Q10 can protect the prepubertal ovarian tissue from ischemia-reperfusion injury in an experimental rat model of ovarian torsion. Materials and Methods. Forty-two female preadolescent Wistar-Albino rats were divided into 6 equal groups randomly. The sham group had laparotomy without torsion; the other groups had torsion/detorsion procedure. After undergoing torsion, group 2 received saline, group 3 received olive oil, group 4 received alpha-lipoic acid, group 5 received coenzyme Q10, and group 6 received both alpha-lipoic acid and coenzyme Q10 orally. The oxidant-antioxidant statuses of these groups were compared using biochemical measurement of oxidized/reduced glutathione, glutathione peroxidase and malondialdehyde, pathological evaluation of damage and apoptosis within the ovarian tissue, and immunohistochemical assessment of nitric oxide synthase. Results. The left ovaries of the alpha-lipoic acid + coenzyme Q10 group had significantly lower apoptosis scores and significantly higher nitric oxide synthase content than the left ovaries of the control groups. The alpha-lipoic acid + coenzyme Q10 group had significantly higher glutathione peroxidase levels and serum malondialdehyde concentrations than the sham group. Conclusions. The combination of alpha-lipoic acid and coenzyme Q10 has beneficial effects on oxidative stress induced by ischemia-reperfusion injury related to ovarian torsion.

Biochemical, Histopathological and Immunohistochemical Evaluation of the Protective and Therapeutic Effects of Thymoquinone against Ischemia and Ischemia/Reperfusion Injury in the Rat Ovary

AIM

To evaluate the antioxidant effects of thymoquinone (TQ) and to investigate the biochemical, histopathological and immunohistochemical changes in experimental rat ovarian torsion.

METHODS

A total of 48 female adult rats were used in this study and randomly divided into 7 groups: (1) sham operation; (2) bilateral 3-hour ovarian ischemia; (3) 3-hour ischemia and 3-hour reperfusion; (4) and (5) rats were administered 20 and 40 mg/kg of TQ, respectively, before 0.5 h of ischemia, and then 3 h of ovarian ischemia was applied; (6) and (7) 3-hour ovarian ischemia was applied; 2.5 h after the induction of ischemia, rats were administered the same doses of TQ; at the end of 3 h of ischemia, a 3-hour reperfusion was applied. Histologic changes under light microscopy, immunoreactivity for anticaspase-3 and serum levels of malondialdehyde, interleukin-6, catalase and glutathione peroxidase were noted and compared between the 7 groups.

RESULTS

Ischemia and ischemia/reperfusion cause a deterioration of biochemical and histopathological parameters. Administration of TQ seems to reverse these alterations and alleviate the injury. Antioxidant defense mechanisms appear to be enhanced by the administration of TQ.

CONCLUSION

TQ at different doses attenuates ovarian ischemia and ischemia/reperfusion injury in rats.

Effects of amlodipine on ischaemia/reperfusion injury in the rat testis

The aim of this study was to examine the effects of amlodipine (AML) in rat testicular torsion/detorsion damage. In this study, rats were divided into eight groups: (i) sham; (ii) testicular ischaemia, 2 h of ischaemia; (iii) testicular ischaemia/reperfusion (I/R), 2 h of ischaemia followed by 2 h of reperfusion; (iv) ischaemia + AML (5 mg kg(-1)) administered 30 min before ischaemia; (v) ischaemia + AML (10 mg kg(-1)) administered 30 min before ischaemia; (vi) and (vii) I/R + AML (5 mg kg(-1)) and I/R + AML (10 mg kg(-1)) administered 1.5 h after the induction of ischaemia, respectively, and at the end of a 2-h ischaemia period and a 2-h reperfusion period applied; and (viii) sham + AML (10 mg kg(-1)). Significant decreases in levels of superoxide dismutase and glutathione were observed in ischaemia and reperfusion groups when compared with healthy controls. These antioxidant levels increased in AML groups while malondialdehyde levels significantly decreased. While increases in tumour necrosis factor-alpha and transforming growth factor-beta levels were found in the torsion and detorsion groups, significant decreases in the levels of these inflammatory cytokines were observed in the treatment groups. These results demonstrate that AML significantly produced protective effects on testis tissue damage that occurs in the torsion/detorsion model via biochemical, histopathological and molecular pathways.

Dose dependent protective effects of vardenafil on ischemia-reperfusion injury with biochemical and histopathologic evaluation in rat ovary

PURPOSE

The purpose of the study is to evaluate the effect of vardenafil on the histopathology and biochemical parameters in reducing damage in experimental ovarian ischemia and ischemia/reperfusion injury in a rat model and to compare the effect of two different doses of vardenafil.

METHODS

Forty-two rats with experimental ovarian torsion. Group-I: sham; Group-II: ovarian ischemia; Group-III: 2 hours of ischemia followed by a 2-hour reperfusion. Group-IV: two hours before the sham operation, rats received 1mg/kg vardenafil; Group V and VI: A 2-hour period of ovarian ischemia was applied, in which rats were treated with intraperitoneal vardenafil 1 and 2mg/kg dose, after 1.5 hours of ovarian ischemia. After 2 hours of reperfusion, the ovaries on the right side were removed for examination. The ovarian ischemia/reperfusion injury was evaluated by calculating total antioxidant status, total oxidant status and oxidative stress index; and histopathologic examination of all ovarian rat tissue.

RESULTS

The histologic findings in vardenafil treatment groups were statistically significant decreased edema and follicle degeneration, with vascular congestion, hemorrhage and follicle degeneration being dose-dependent. There were no statistically significant changes in the biochemical parameters.

CONCLUSIONS

According to histopathological examination, low and high dose vardenafil is effective in attenuating ischemia-reperfusion induced ovary injury.

Effect of detorsion alone and in combination with enoxaparin therapy on ovarian reserve and serum antimüllerian hormone levels in a rat ovarian torsion model

OBJECTIVE

To investigate the effect of enoxaparin on ovarian reserve and serum antimüllerian hormone (AMH) levels in a rat ovarian torsion model.

DESIGN

Experimental study.

SETTING

Experimental surgery laboratory in a training and research hospital.

ANIMAL(S)

Fourteen female Wistar Hannover rats.

INTERVENTION(S)

1) Control group received no special treatment other than abdominal exposure; 2) detorsion-only group received bilateral adnexal torsion (3-hour ischemia), and then after 3-hour torsion period, detorsion (reperfusion) was performed; and 3) detorsion-enoxaparin group received 0.5 mg/kg enoxaparin subcutaneously 2 hours before the same surgery as the detorsion-only group and a second 0.5 mg/kg dose of enoxaparin 24 hours after the first surgeries. Apart from the surgeries, preoperative and postoperative 1-mL blood samples were drawn from the right jugular vein of each rat.

MAIN OUTCOME MEASURE(S)

Preoperative and postoperative serum AMH levels, histopathologic damage scores, and follicle counts in the ovarian tissue of the rats.

RESULT(S)

Vascular congestion and hemorrhage scores were higher in the detorsion-enoxaparin group than in the detorsion-only and control groups. The number of small antral follicles was smaller in the detorsion-only group than in the control group. The difference in the pre- and postoperative AMH levels was higher in the detorsion-only group than in the control and detorsion-enoxaparin groups.

CONCLUSION(S)

The combination of enoxaparin therapy with conventional ovarian detorsion is more effective in protecting the ovarian reserve than detorsion alone.

Protective effect of oxytocin on ovarian ischemia-reperfusion injury in rats

Oxytocin (OT), a neurohypophysial nonapeptide, plays dual role as a neurotransmitter/neuromodulator and a hormone. It has also well known protective properties against ischemia/reperfusion organ damage. This study investigated the effect of OT on experimentally induced ovarian torsion/de-torsion ischemia/reperfusion (I/R) injury in rats. Sprague-Dawley rats were assigned to five treatment groups (n=7/group): Group 1, sham-operated; Group 2, torsion; Group 3, 80 IU/kg of OT administration 30 min prior to torsion; Group 4, torsion/de-torsion; and Group 5, torsion followed by 80 IU/kg of OT administration 30 min prior to de-torsion. OT administration significantly decreased the tissue malondialdehyde (MDA) levels in both the torsion and OT group (Group 3), and torsion/de-torsion OT group (Group 5) in comparison with the torsion-only group (Group 2) and torsion/de-torsion group (Group 4). Histopathological finding scores including follicular degeneration, edema, hemorrhage, vascular congestion, and infiltration by inflammatory cells were found to be significantly decreased in the torsion and OT group (Group 3), and torsion/de-torsion OT group (Group 5) when compared with the torsion-only group (Group 2) and torsion/de-torsion group (Group 4). In conclusion, these results, verified with histopathologic evaluation and biochemical assays, suggest a probable protective role for OT in ischemia and I/R injury in rat ovaries.

The effects of zileuton and montelukast in reperfusion-induced arrhythmias in anesthetized rats

Background

5-Lipoxygenase is an enzyme involved in the synthesis of leukotriene eicosanoids from arachidonic acid. The therapeutic potential of zileuton, an inhibitor of 5-lipoxygenase, and montelukast, a cysteinyl leukotriene receptor antagonist, for the treatment of ischemia/reperfusion (I/R) injury of the heart has been proposed in a few studies. However, the effects of zileuton and montelukast on I/R-induced arrhythmias have not been determined.

Objective

We assessed the possible protective effects of zileuton and montelukast against I/R-induced arrhythmias.

Methods

Forty-five male Wistar albino rats were divided into 5 groups, each containing 9 rats. Group 1: control, Groups 2 and 3: rats treated with montelukast (10 and 30 mg/kg IP); and Groups 4 and 5: rats treated with zileuton (1 and 3 mg/kg IV) 15 minutes before the induction of ischemia. Ischemia and reperfusion were induced by occluding the left main coronary artery of anesthetized rats for 6 minutes followed by reopening the artery for 6 minutes.

Results

Both doses of zileuton decreased the mean [SE] arrhythmia score (zileuton 1 mg/kg: 1.4 [0.8]; zileuton 3 mg/kg: 1.3 [0.5] vs control: 2.9 [0.3]; P < 0.05), the duration of ventricular tachycardia, and the total length of arrhythmias, but montelukast was not effective to decrease the ventricular arrhythmias during the 6 minutes of reperfusion.

Conclusions

The results indicate for the first time that zileuton exerts an antiarrhythmic effect at different doses and that montelukast is not effective against I/R-induced arrhythmias. These results indicate that zileuton may be a candidate for drug treatment of I/R-induced arrhythmias.

Montelukast prevents ischaemia/reperfusion-induced ovarian damage in rats

OBJECTIVE

To investigate the efficacy of montelukast for prevention of ischaemia/reperfusion (I/R) injury in rat ovary.

STUDY DESIGN

Twenty-four female adult rats were included in the study. I/R injury was induced by CO2 pneumoperitoneum in a laparoscopic rat model. The rats were divided at random into three groups: the sham group was subjected to catheter insertion but was not subjected to pneumoperitoneum; the saline group was subjected to 60 min of pneumoperitoneum and 30 min of reperfusion, with 1 mg/kg physiological saline administered 10 min before pneumoperitoneum; and the montelukast group was subjected to 60 min of pneumoperitoneum and 30 min of reperfusion, with 20mg/kg montelukast administered 10 min before pneumoperitoneum. Damage to ovarian tissue was scored by histopathological evaluation. Caspase-3 expression was determined immunohistochemically. Ovarian tissue levels of malondialdehyde and glutathione, and plasma total antioxidant capacity were measured biochemically.

RESULTS

In comparison with the sham group, ovarian sections in the montelukast group had higher scores for follicular degeneration and oedema (p<0.001). Montelukast treatment prevented tissue damage in ovaries, and this result was significant. Caspase-3 expression was only observed in ovarian surface epithelium in the saline and montelukast groups. However, the mean caspase-3 expression score was higher in the saline group than the montelukast group (p<0.001). Tissue levels of malondialdehyde were higher in the montelukast group than the sham group, but plasma total antioxidant capacity and tissue levels of glutathione were significantly lower. Pretreatment with montelukast reduced lipid peroxidation (p<0.005) and improved antioxidant status in rats (p<0.001).

CONCLUSION

Montelukast is effective for the prevention of I/R-induced damage in rat ovary.

Vitamin E modulates apoptosis and c-jun N-terminal kinase activation in ovarian torsion-detorsion injury

The aim of this study was to evaluate the role of vitamin E in follicular degeneration and to assess histopathological and biochemical changes following ischemia-reperfusion (IR) injury in rat ovaries. Twenty-eight Wistar albino rats were randomly divided into four groups: sham, 4h torsion, 24h detorsion, and a vitamin E group. Thirty minutes before detorsion, a single dose of 200mg/kg vitamin E was administered intraperitoneally. The ovarian histology score was determined, serum levels of malondialdehyde (MDA) and myeloperoxidase (MPO) were measured. The apoptosis of granulosa cells and the phospho-c-jun N-terminal kinase (p-JNK) and phospho-p38 (p-p38) immunoreactivities of these cells were determined. MDA and MPO levels were significantly increased in the torsion and detorsion groups. Hemorrhage, edema, and congestion were also apparent in these groups. In addition, the apoptotic index and the immunoreactivity of p-JNK were highest in the detorsion group, which also showed marked follicular degeneration. However, p-p38 activity was not affected by torsion-detorsion (TD) induction. Vitamin E ameliorated TD-induced histological alterations. It also decreased serum levels of MDA and MPO, reduced the activity of p-JNK in the ovaries, and reduced numbers of apoptotic follicular cells. In conclusion, these data indicate that vitamin E attenuated ovarian follicular degeneration by inhibiting the immunoreactivity of p-JNK and reducing the apoptosis of granulosa cells.

Blockade of endothelin receptors with bosentan limits ischaemia/reperfusion-induced injury in rat ovaries

OBJECTIVE

To investigate the role of endothelin receptors in ovarian ischaemia/reperfusion (I/R) injury in rats using the endothelin receptor antagonist bosentan.

STUDY DESIGN

Group 1: sham operation; Group 2: sham operation and bosentan 60 mg/kg; Group 3: bilateral ovarian ischaemia; Group 4: 3-h period of ischaemia followed by 3h of reperfusion; Groups 5 and 6: bosentan 30 and 60 mg/kg, respectively, with bilateral ovarian ischaemia applied 30 min later; the bilateral ovaries were removed after 3h of ischaemia; Groups 7 and 8: 3h of bilateral ovarian ischaemia was applied, with bosentan 30 and 60 mg/kg, respectively, administered 2.5h after the induction of ischaemia; following the 3-h period of ischaemia, 3h of reperfusion was applied, after which the ovaries were removed.

RESULTS

Ischaemia and I/R decreased superoxide dismutase (SOD) activity and the level of glutathione (GSH) in ovarian tissue, but increased the level of malondialdehyde (MDA) significantly compared with the sham operation group. Bosentan 30 and 60 mg/kg before ischaemia and I/R decreased the MDA level and increased SOD activity and the GSH level in the experimental groups. The serum levels of the inflammatory cytokines interleukin (IL)-1β, IL-6 and tumour necrosis factor-α were also measured in the I/R injury model in rat ovaries. The levels of these cytokines were significantly higher in the ischaemia and I/R groups compared with the sham operation and sham operation plus bosentan groups. The histopathological findings also demonstrated the protective role of bosentan against I/R-induced injury in rat ovaries.

CONCLUSION

Administration of bosentan protects the ovaries against oxidative damage and I/R-induced injury.

[Ovarian cryopreservation: what future?]

Ovarian cortex cryobanking is a technique of fertility preservation that led to the birth of about 20 children in the world since 2004. Its main limitations are low follicular survival rate after thawing and transplantation and the risk of disease reintroduction. A lot of research is currently conducted in order to optimize both efficacy and safety of the graft and to develop alternative techniques to restore fertility. These advances will allow oncologists to offer this technique to a growing number of patients in the context of fertility preservation (for medical or social indications), but also in other indications such as puberty induction or menopause treatment.