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

The Effects of Dexmedetomidine on Abdominal Aortic Occlusion-Induced Ovarian Injury via Oxidative Stress and Apoptosis

Ischemia/reperfusion (I/R) induced ovarian damage is caused by various diseases such as ovarian torsion, ovarian transplantation, cardiovascular surgery, sepsis, or intra-abdominal surgery. I/R-related oxidative damage can impair ovarian functions, from oocyte maturation to fertilization. This study investigated the effects of dexmedetomidine (DEX), which has been shown to exhibit antiapoptotic, anti-inflammatory, and antioxidant effects, on ovarian I/R injury. We designed four study groups: group 1 (n = 6): control group; group 2 (n = 6): only DEX group; group 3 (n = 6): I/R group; group 4 (n = 6): I/R + DEX group. Then, ovarian samples were taken and examined histologically and immunohistochemically, and tissue malondialdehyde (MDA) and glutathione (GSH) levels were measured. In the I/R group MDA levels, caspase-3, NF-κB/p65, 8-OHdG positivity, and follicular degeneration, edema, and inflammation were increased compared to the control group (p = 0.000). In addition, GSH levels were significantly decreased in the I/R group compared to the control group (p = 0.000). On the other hand, in the I/R + DEX treatment group MDA levels, caspase-3, NF-κB/p65, 8-OHdG positivity, follicular degeneration, edema, and inflammation findings were decreased than in the I/R group (p = 0.000, p = 0.005, p = 0.005, p = 0.001, p = 0.005, respectively). However, GSH levels increased significantly in the I/R + DEX treatment group compared to the I/R group (p = 0.000). DEX protects against ovarian I/R injury through antioxidation and by suppressing inflammation and apoptosis.

Urapidil alleviates ovarian torsion detorsion injury via regulating oxidative stress, apoptosis, autophagia, and inflammation

Objective(s):

This study aimed to determine anti-inflammatory, antioxidant, and antiapoptotic properties of urapidil (Ura) against ovarian torsion detorsion (T/D) injury in rats.

Materials and Methods:

40 female Wistar albino rats were grouped as sham, T/D, T/D+dimethyl sulfoxide (DMSO), T/D+Urapidil (Ura) 0.5 mg/kg (low dose), and T/D+Urapidil (Ura) 5 mg/kg (high dose) groups. In treatment groups, Ura was administered intraperitoneally just before detorsion. Biochemical parameters (TAS, TOS, MDA, MPO, and SOD) and immunohistochemical (IL-1β, TNF-α, NF-κB, LC3B, and Caspase-3) analyzes were performed.

Results:

In the T/D group, OSI and MPO levels were elevated significantly while TAS values decreased compared with the sham group. A significant difference occurred in the low dose treatment group in TAS and OSI levels compared with the T/D group. In the high dose treatment group, significant elevation in TAS but reduction in OSI and MDA levels were observed compared with the T/D group. Immunohistochemical staining resulted in IL-1β, TNF-α, NF-κB, LC3B, and caspase-3 immunopositivity in the T/D group, while Ura treatment decreased those parameters. Intensive congestion and hemorrhage were observed in the T/D group, but contrary to this, treatment groups had alleviated congestion and hemorrhage.

Conclusion:

These results suggest that Ura demonstrated protective effects against ovarian T/D injury via anti-oxidative, anti-inflammatory, and anti-apoptotic features.

Protective Effects of Reduced Glutathione and Ulinastatin on Xeno-transplanted Human Ovarian Tissue Against Ischemia and Reperfusion Injury

Recently, transplantation of cryopreserved ovarian tissue is the method for fertility preservation for oncologic and nononcologic reasons. The main challenge of ovarian cryopreservation followed by transplantation is that ischemia reperfusion injury (IRI) induced the loss of follicles. The aim of this study was to evaluate the effects of glutathione (GSH), ulinastatin (UTI) or both (GSH+UTI) on preventing ischemia reperfusion-induced follicles depletion in ovarian grafts.

Ovarian fragments were collected from 20 women aged 29±6 years. Frozen-thawed human ovarian tissue was xenografted into SCID mice, at the same time GSH, UTI and GSH+UTI was administrated respectively. The ovarian grafts were collected at the 1st, 3rd, 7th, 14th, 28th, 56th, and 85th day after xenotransplantation. Follicle survival rate was measured by H&E staining and Live/Dead staining. Angiogenic activity and macrophage recruitment was evidenced by immunohistochemical staining. The oxidative stress and inflammatory cytokines in human ovarian xenografts were measured by real-time PCR. The results indicated that after the treatments of GSH, UTI and GSH+UTI in the hosts, follicular survival in ovarian grafts were improved. The level of VEGF, CD31, and antioxidant enzymes superoxide dismutase 1 and superoxide dismutase 2 in ovarian grafts were increased. Accumulation of macrophages, level of IL6 and TNF-α, as well as malondialdehyde was decreased in ovarian grafts from treated groups. In conclusion, administration of GSH, UTI and GSH+UTI decreased the depletion of follicles in human grafts post-transplantation by inhibiting IRI-induced antiangiogenesis, oxidative stress and inflammation.

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 effects of bosentan on hyperoxia-induced lung injury in neonatal rats

BACKGROUND

Bronchopulmonary dysplasia (BPD) remains an important cause of morbidity and mortality in premature infants. There is currently no proven effective treatment modality for BPD, and inflammation and oxidative injury play an important role in the pathogenesis of this disease. This study investigated the histopathological and biochemical effects of bosentan, which is a non-specific endothelin receptor antagonist with known antioxidant and anti-inflammatory properties, on hyperoxia-induced lung injury (HILI) in neonatal rats.

METHODS

The experiment was performed on newborn rats from the 3rd to the 13th postnatal day. The rats were randomly divided into six groups: Group 1 (air-exposed + saline, n = 6); Group 2 (HILI, n = 8); Group 3 (air-exposed + bosentan, n = 7); Group 4 (HILI + saline, n = 7); Group 5 (HILI + early bosentan-treated group, n = 6), and Group 6 (HILI + late bosentan-treated group, n = 7). Bosentan was administered (30 mg/kg/day) intraperitoneally. The histopathological effects of bosentan on lung tissue were assessed by their alveolar surface area, fibrosis, and smooth muscle actin (SMA) scores, and the biochemical effects on lung tissue were assessed by interleukin-1 beta (IL-1β), IL-6, IL-10, and tumor necrosis factor-alpha (TNF-α).

RESULTS

The alveolar surface area and fibrosis scores were found to be significantly higher in HILI groups compared with Group 1 (P < 0.01). The SMA scores in HILI groups were also significantly higher than Group 1 (P < 0.01). Bosentan treatment, especially late therapy, reduced all of these histopathological scores and the levels of IL-6 and TNF-α in the hyperoxia groups (P < 0.01).

CONCLUSION

This experimental study showed that bosentan had a protective effect on hyperoxic lung injury through its anti-inflammatory properties.

The effect of rutin on ovarian ischemia-reperfusion injury in a rat model

The effect of rutin on ovarian ischemia-reperfusion (I/R) injury was investigated in this experimental study. Eighteen Wistar albino female rats were divided into three groups as follows: I/R group (IRG; n = 6), 50 mg/kg rutin + I/R group (RG; n = 6), and a healthy control group scheduled for a sham operation (SG; n = 6). 2 h of ischemia and following 2 h of reperfusion were created in the IRG and RG by using a torsion model involving atraumatic vascular clips. Rutin, a flavonoid glycoside, was injected intraperitoneally at the dose of 50 mg/kg to RG group 1 h before reperfusion. Then, rats were euthanized and their ovaries were removed for biochemical and histopathological examination and also assessment of the gene expressions. IRG group had a significant increase in malondialdehyde (MDA) levels, in the expressions of tumor necrosis factor alpha (TNF-α) and interleukin 1 beta (IL-1β), and also in the activity of cyclooxygenase 2 (COX-2) unlike the significant decrease in total glutathione (tGSH) levels and the activity of COX-1 when compared to the SG group. However, rutin significantly decreased MDA levels, the expressions of TNF-α and IL-1β, and also the activity of COX-2 while it increased significantly tGSH levels and the activity of COX-1 in the RG group in comparison with the IRG group. Rutin ameliorated the I/R-induced ovarian injury in rats via its possible antioxidative and anti-inflammatory effects.

Nigella Sativa Oil Protects the Rat Ovary from Oxidative Injury Due to Ischemia-Reperfusion

Background

The aim of this study was to evaluate the effects of Nigella sativa (N. sativa) oil (NSO) on ovarian oxidative damage following ischemia-reperfusion injury, using a rat model of ovarian torsion.

Material/Methods

Forty-eight female albino Wistar rats were divided into six groups: (Group 1) laparotomy only; (Group 2) intraperitoneal NSO (2 ml/kg), 1 hour following laparotomy; (Group 3) 3 hours of ovarian ischemia; (Group 4) 3 hours of ovarian ischemia followed by 3 hours of reperfusion; (Group 5) 3 hours of ovarian ischemia and 2 ml/kg of NSO 1 hour before laparotomy; (Group 6) 3 hours of reperfusion after 3 hours of ovarian ischemia and 2 ml/mg of NSO 1 hour before laparotomy.

Results

The antioxidant status, ceruloplasmin level, native thiol, total thiol, and disulfide levels of the control group (Group 1) were significantly increased compared with the ovarian ischemia-reperfusion group treated with NSO (Group 6) (p=0.003, p=0.002, p=0.006, p=0.001 and p=0.003, respectively); these levels in the ovarian ischemia group (Group 3) and ischemia-reperfusion group (Group 4) were statistically similar to those of the ovarian ischemia + NSO group (Group 5) and ovarian ischemia-reperfusion + NSO group (Group 6).

Conclusions

In this preliminary rat study, administration of NSO shortly after the onset of ovarian ischemia-reperfusion injury, did not significantly reduce levels of markers of oxidative injury. Further studies are required to evaluate the ovarian changes at the tissue level, and to determine the optimum dose of NSO.

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.

Effects of carvedilol on an ischemia/reperfusion model: Biochemical, histopathological and immunohistochemical evaluation

AIM

The aim of this study was to investigate the effects of carvedilol (CVD) on experimentally induced ovarian ischemia/reperfusion (I/R) injury in rats.

METHODS

An ovarian I/R model was applied to rats, classified into three groups: 1 (n = 7), sham operated (control); 2 (n = 7), 3 h ischemia + 3 h reperfusion (I/R); 3 (n = 7), 3 h ischemia + CVD + 3 h reperfusion (I/R + CVD). Malondialdehyde (MDA) levels and glutathione peroxidase (GSH-Px) and superoxide dismutase (SOD) activities in ovarian tissues and serum were measured. Tissue damage was examined histopathologically; Bax and caspase-3 expression was determined immunhistochemically. Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay was performed to show apoptotic cell death.

RESULTS

MDA levels in ovarian tissues were significantly increased in the I/R group compared with the control. CVD administration significantly decreased tissue MDA levels in the I/R + CVD in comparison with the I/R group. GSH-Px activities in serum were higher in the I/R + CVD than in the I/R group. SOD activities in tissue and serum were significantly decreased in the I/R compared with the control group. Histological examination showed a significant improvement in ovarian morphology in the I/R + CVD compared with the I/R group. Bax and caspase-3 protein was more strongly expressed in the I/R group compared with the control and I/R + CVD groups. Apoptotic index detected by TUNEL assay was significantly increased in the I/R and decreased in the I/R + CVD group.

CONCLUSION

Our results suggest that CVD reduces the deleterious effects of oxidative damage on ovaries in a rat I/R model.

The role of endothelin-1 and endothelin receptor antagonists in inflammatory response and sepsis

Endothelin-1 (ET-1) is a potent endogenous vasoconstrictor, mainly secreted by endothelial cells. It acts through two types of receptors: ETA and ETB. Apart from a vasoconstrictive action, ET-1 causes fibrosis of the vascular cells and stimulates production of reactive oxygen species. It is claimed that ET-1 induces proinflammatory mechanisms, increasing superoxide anion production and cytokine secretion. A recent study has shown that ET-1 is involved in the activation of transcription factors such as NF-κB and expression of proinflammatory cytokines including TNF-α, IL-1, and IL-6. It has been also indicated that during endotoxaemia, the plasma level of ET-1 is increased in various animal species. Some authors indicate a clear correlation between endothelin plasma level and morbidity/mortality rate in septic patients. These pathological effects of ET-1 may be abrogated at least partly by endothelin receptor blockade. ET-1 receptor antagonists may be useful for prevention of various vascular diseases. This review summarises the current knowledge regarding endothelin receptor antagonists and the role of ET-1 in sepsis and inflammation.