Does gradual detorsion protect the ovary against ischemia-reperfusion injury in rats?

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.

Artemisinin reduces acute ovarian ischemia-reperfusion injury in rats

Artemisinin (ARS) is well known as an effective agent in the treatment of malaria through the rapid elimination of Plasmodium falciparum parasites. This study aims to investigate the effect of ARS in treating adnexal torsion, one of the most common gynecological surgical emergencies. ARS was administered intraperitoneally once 30 min before unilateral ovarian torsion in two different doses (10 mg/kg vs. 50 mg/kg). Torsion was maintained for 3 h and then held in the detorted state for 3 h. Bilateral adnexectomy was performed to measure antioxidant enzyme activities and oxidant levels on the ipsilateral ovary and to make histopathological and immunohistochemical analyses on the contralateral ovary. Ischemia-reperfusion (I/R) injury dramatically upregulated the activities of CAT, GST, and MDA levels in the ipsilateral ovary, which were all downregulated by ARS treatment. A significant increase in follicular cell degeneration, congestion, and edema in the contralateral ovary was seen in the I/R group, which was significantly reduced with ARS treatment. Furthermore, I/R injury resulted in a significant increase in apoptosis as shown by the increased levels of BAX and CASP-3, and decreased levels of BCL-2 whereas ARS significantly reduced the impact of the injury. Our data, based on a rat I/R injury model, show that both ipsilateral and contralateral ovaries are protected with ARS pretreatment, and 50 mg/kg ARS treatment demonstrates to be more effective than the 10 mg/kg ARS.

Cysteamine Attenuate Intestinal Reperfusion Injury Induced by Occlusion of Mesenteric Artery by Enhancing Intracellular Thiol Activities

BACKGROUND

Ischemia/reperfusion has been reported to further damage the intestine reperfusion injury (IRI) and cause multiple distal organ dysfunction through oxidative stress, inflammation, and apoptosis. Cysteamine is known to inhibit oxidative stress, inflammatory cytokines and apoptosis. This experiment was designed to evaluate the role of cysteamine against IRI in rats METHODS: Thirty-two Wistar rat strains were assigned to four groups: sham, Intestinal-reperfusion injury (IRI), 50 mg/kg and 100 mg/kg cysteamine treatment IRI. A 5 cm segment of terminal ileum was twisted 360° clockwise along the mesentery for 45 minutes to induce ischemia before detorsion. Tissues were preserved for biochemical evaluation and histology 4 hours after detorsion. Activities of GPx, GSH, protein and non-protein thiol, H₂O₂, MDA were evaluated. Serum concentration of nitrite, MPO, ALT, AST TNF-alpha and IL-6 were measured. Caspase 3 and bax were evaluated by immunohistochemistry. Statistical significance was set as p<0.05 RESULTS: Significant (p<0.05) increase in H₂O_2, MDA and nitrite but reduction in GPx, GSH, protein thiol and non-protein thiol in the IRI rats was reversed by 50 and 100 mg/kg cysteamine. Serum MPO, TNF-α, IL6, AST and ALT was significantly elevated in IRI while the rats treated with cysteamine showed a significant decrease (p<0.05) in the activities of these inflammatory and hepatic injury markers.

CONCLUSION

Cysteamine mitigate IRI by enhancing intracellular antioxidant defense system, inhibiting inflammatory mediators and intestinal tissue expression of pro-apoptotic protein.

Appearances Are Deceptive: Two Case Reports in Teenagers on the Conservative Laparoscopic Surgery for Adnexal Torsion with Apparent Infarction

Introduction. Torsion of the ovary, tube, or both is estimated to be responsible for 2-7% of all gynaecological emergencies. Oophorectomy is commonly performed for adnexal torsion with a possible negative impact on fertility in women of reproductive age. Case Presentations. We report two cases of teenage girls presented with adnexal torsion describing their laparoscopy features. Detorsion without additional surgical intervention could save their ovaries. Discussion. Detorsion is a more conservative surgical approach that should be considered in all younger women with ovarian torsion.

Cysteamine mitigates torsion/detorsion-induced reperfusion injury via inhibition of apoptosis, oxidative stress and inflammatory responses in experimental rat model

Oxidative stress, inflammation and apoptosis are major pathways in pathophysiology of testicular torsion/detorsion (TTDT) reperfusion injury. This study evaluated the antioxidant, anti-inflammatory and anti-apoptotic role of cysteamine in TTDT-induced injury. Male Wistar rats (n = 32) were grouped into four (n = 8): sham, ischaemia-reperfusion injury (IRI), cysteamine (100 mg/kg and 200 mg/kg) for in vivo study. Samples were taken for biomolecular and histological evaluation 48 hr after detorsion. Tissue SOD, GPx, GSH, GST activity, total thiol, H₂ O₂ and MDA were assessed. Serum levels of NO, MPO, TNF-alpha and IL-6 and sperm motility, count and viability were assessed. Caspase-3 and bax were evaluated by immunohistochemistry. Significant difference was set as p < .05. Significant increase in H₂ O_2, MDA and nitrite but reduction in SOD, GPx, GSH, GST and total thiol in the testicular tissue of IRI rats was reversed by cysteamine. Serum MPO and TNF-α were significantly elevated in RI, while treated-RI rats showed decrease (p < .05) in tissue level of the inflammation markers. Reduced sperm motility in RI was significantly reversed by cysteamine. Increased tissue expression of bax and caspase-3 was reversed by cysteamine. Cysteamine protected the testis against reperfusion injury through anti-inflammatory, antioxidant effects and inhibition of apoptosis in rats.

The long-term protective effect of hypothermia and gradual detorsion on ovarian tissue in adnexal torsion/detorsion model in rats

INTRODUCTION

Ischemia in ovarian torsion and subsequent reperfusion has significant effects on fertility in the long term. The most important reason for these changes is thought to be a reperfusion injury rather than ischemia. We aimed to evaluate whether the reperfusion injury following ovarian detorsion could be reduced by hypothermia and intermittent reperfusion.

MATERIALS AND METHODS

Forty adult female rats were divided into five groups as follows: Sham (Sh) (n = 8), torsion detorsion (control TD) (n = 8), progressive reperfusion "gradual detorsion" (GD) (n = 8), hypothermia (H) (n = 8) and the progressive reperfusion + hypothermia (GD + H) (n = 8). In all rats, except for the Sh group, the left ovary was rotated counter clockwise 1080° and fixed to the abdominal wall by three 5-0 non-absorbable sutures followed by the closure of the laparotomy. After 30 h, reperfusion was achieved following the detorsion of the ovaries. In both the control TD and H groups, the torsed ovaries were detorsed. H group, however, was subjected to hypothermia with ice packs 30 min before and during the detorsion. Tissue temperature was kept constant at 4 °C, controlled by a digital thermometer. In the GD group, the torsed ovary and pedicle were detorsed by 360°, followed by a 5 min pause. This procedure was repeated twice until a complete detorsion was achieved. GD + H group underwent hypothermia with ice packs 30 min before the procedure and the torsed ovary and pedicle were detorsed by 360°. After a 5 min pause, we repeated this process twice to provide full detorsion. The tissue temperature was constantly held at 4 °C. In the hypothermia groups, we applied hypothermia for an additional 30 min after detorsion and then left the rats at normal body temperature during reperfusion. We followed the rats in all groups for 60 days. Then we excised the left ovaries of all rats through laparotomy and spared some of the ovaries for biochemical and pathological examination. Intracardiac blood was taken at the end of the procedure and it was sent to the biochemical laboratory to assess oxidative stress markers. Finally, all the animals were sacrificed with high-dose of anesthesia.

RESULTS

Evaluation of the results revealed that oxidative stress markers were significantly lower, and antioxidant parameters were higher in the experimental groups compared with the control TD group (p < 0.05). Histopathologically, we found that tissues were preserved in GD, H, GD + H groups (p < 0.05). When we compared the groups among each other, both biochemical and histopathological values in GD + H group showed that the tissue was preserved from oxidative damage, albeit the difference did not reach a level of significance.

DISCUSSION

Several studies have shown that both hypothermia and intermittent reperfusion protect tissue from IR damage in the early period. However, as far as we know there is no study on long-term outcomes of both practices. Our study showed that both hypothermia and intermittent reperfusion alone protect tissue from IR damage in the long term. However, it did not show the superiority of the combination of both methods compared to that of individual application. The advantages of these methods lie in their easy application and cost-effectiveness. We believe that our study will serve as a base for future studies on the subject.

Ischemia modified albumin in experimental ovarian torsion with and without controlled reperfusion

Purpose: Ovarian torsion, being a gynecological emergency, requires to be rapidly diagnosed and treated with minimal consequences on ovarian function after the removal of torsion. As ischemia modified albumin (IMA) is considered a good biomarker in diverse ischemic diseases, the aim of our study was to determine the effect of different ovarian torsion/detorsion models on serum and ovarian homogenates levels of IMA in an experimental study.

Methods: IMA was measured in the serum and ovarian homogenates of 7 groups of female rats (10 animals in each group): 1 - control (no intervention); 2 - sham (only laparotomy); 3 - ischemia group: 3 hours ovarian torsion (OT); 4 - 3 hours OT (ischemia), 1 hour simple reperfusion; 5 - 3 hours ischemia, 1 hour controlled reperfusion that was assured during the first two minutes by opening and closing the clips on the ovarian pedicles in 10 seconds intervals, followed by simple reperfusion; 6 - 3 hours ischemia, 24 hours simple reperfusion; 7 - 3 hours OT, 24 hours controlled reperfusion. The results were analyzed by Welch’s ANOVA and Spearman correlation.

Results: Ischemia increases the IMA in both serum and ovarian homogenates compared to control and sham groups. The controlled reperfusion groups had a statistically significant lower IMA in serum compared to simple reperfusion groups. IMA was found to be higher in the ovarian homogenates of simple reperfusion compared to controlled reperfusion groups.

Conclusion: Our results suggest that controlled reperfusion prevent the processes that increase the IMA in ovarian torsion.

Magnesium: does it reduce ischemia/reperfusion injury in an adnexal torsion rat model?

Aim

The aim of the present study was to assess the protective effects of magnesium sulfate (MgSO₄) on ischemia/reperfusion (I/R) induced ovarian damage in a rat ovarian torsion model.

Methods

Forty-two female Sprague Dawley rats were included in the study. They were divided into six groups as Group 1, sham; Group 2, bilateral ovarian torsion; Group 3, bilateral ovarian torsion–detorsion; Group 4, MgSO₄–sham; Group 5, MgSO₄–bilateral ovarian torsion; Group 6, bilateral ovarian torsion–MgSO₄–detorsion. Both torsion and detorsion periods lasted 3 hours. In Groups 4, 5 and 6, MgSO₄ (600 mg/kg) was administered by intraperitoneal route 30 minutes before sham operation, torsion and detorsion, respectively. At the end of the study period, both ovaries were removed. One of the ovaries was used for histopathological analyses and the other for biochemical analyses.

Results

In the torsion–detorsion group, all the histopathological scores were higher compared to the sham and torsion only group (p<0.05). Administration of MgSO₄ only caused significant decrease in the inflammatory cell scores of the torsion–detorsion group (p<0.05). MgSO₄, whether given before torsion or before detorsion, suppressed malondialdehyde levels when compared to the untreated groups (p<0.01 and p<0.001, respectively). Glutathione peroxidase activities were significantly higher in the MgSO₄ applied torsion and detorsion groups than Groups 2 and 3 (p<0.05, for both). Administration of MgSO₄ also caused an increase in glutathione levels in the torsion and detorsion groups compared to the torsion only and detorsion only groups (p<0.05, for both). Also, total oxidant status levels decreased in the MgSO₄ applied torsion and detorsion groups compared to the untreated corresponding ones (p<0.01 and p<0.001, respectively). MgSO₄ significantly decreased the Oxidative Stress Index levels in the torsion–detorsion group compared to Group 2 (p<0.001).

Conclusion

Histopathological and biochemical analysis revealed that prophylactic treatment with MgSO₄ reduces the changes observed in I/R injury in a rat model.

Effects of curcumin on ovarian ischemia-reperfusion injury in a rat model

Ischemia-reperfusion injury is a significant problem following reperfusion treatment for ovarian torsion. It is generally caused by reactive oxygen species-induced damage. Antioxidant agents, such as curcumin, may protect ovaries from this adverse effect. The aim of the present randomized, controlled study was to evaluate the short-term protective effect of curcumin on a rat model of ovarian ischemia-reperfusion injury. A total of 30 female Wistar albino rats, weighing 160-230 g, were divided into 2 groups depending upon the time of unilateral, left ovary ischemia/reperfusion (group 1, 2 h ischemia/2 h reperfusion and group 2, 4 h ischemia/4 h reperfusion). These groups were subdivided into 3 subgroups (sham, control and curcumin). The sham subgroups were not subjected to ischemia/reperfusion. Control and curcumin subgroups were performed under ischemia for 2 h plus 2 h reperfusion or 4 h ischemia plus 4 h reperfusion. Curcumin, 200 mg/kg, was intraperitoneally administered simultaneously with reperfusion to the curcumin subgroups. Serum nitric oxide (NO), NO synthase (NOS), xanthine oxidase (XO), total antioxidant status (TAS), total oxidant status (TOS) and histological scores were measured and compared between subgroups. For group 1, no significant differences were observed between NO, NOS, XO, TAS or TOS. The left ovary histological grade was significantly higher in the control and curcumin subgroups compared with the sham subgroup (P=0.036). For group 2, TOS was significantly higher in the control group compared with the sham and curcumin groups (P=0.023). However, TAS was also significantly higher in the control subgroup compared with the other 2 subgroups (P=0.005). Left ovary histological grade was significantly higher in the control and curcumin subgroups compared with the sham subgroup (P=0.038). No significant differences were observed between NO, NOS or XO between the group 2 subgroups. The results showed that curcumin exerted no major significant protective effect on ischemia-reperfusion injury in the rat ovary.

The Effect of Controlled Reperfusion in the Prevention of Infertility Caused by Ischemia Induced in the Contralateral Ovary in Rats with Unilateral Ovariectomy

BACKGROUND/AIMS

To investigate the effectiveness of controlled reperfusion (CR) on ovarian tissue malondialdehyde, total glutathione and 8-hydroxyguanine levels and infertility rates in a rat model of induced ischemia-reperfusion (I/R) injury with unilateral oophorectomy.

METHODS

A total of 135 adult female albino Wistar rats were divided into 9 groups (n = 15 for each group): unilateral ovariectomy + ovarian I/R (OIR), unilateral ovariectomy alone (OEG), a sham operation group (SG), and unilateral ovariectomy + CR performed at different intervals (the clips were released 10 times for 10, 8, 6, 4, 2 or 1 s and closed again 10 times for 10, 8, 6, 4, 2 or 1 s; OCR-1-6, respectively). Five rats from each group were sacrificed, and their ovaries were removed.

RESULTS

Higher ovarian tissue malondialdehyde and 8-hydroxyguanine levels and lower ovarian tissue total glutathione levels were found in the OIR group compared with the SG, OEG and OCR-4-6 groups. The number of rats giving birth during the study period was found to be similar among the SG (n = 8), OEG (n = 8) and OCR-6 (n = 7) groups.

CONCLUSION

These results suggest that sterility and ovarian oxidative stress caused by I/R injury decreases in parallel to the shortening of CR duration.