The protective effects of tacrolimus on rat uteri exposed to ischemia-reperfusion injury: a biochemical and histopathologic evaluation

Tacrolimus trough level and oxidative stress in Tunisian kidney transplanted patients

BACKGROUND

The effect of tacrolimus (TAC) on oxidative stress after kidney transplantation (KT) is unclear. This study aimed to evaluate the influence of TAC trough levels of oxidative stress status in Tunisian KT patients during the post-transplantation period (PTP).

METHODS

A prospective study including 90 KT patients was performed. TAC whole-blood concentrations were measured by the microparticle enzyme immunoassay method and adjusted according to the target range. Plasma levels of oxidants (malondialdehyde (MDA) and advanced oxidation protein products (AOPP)) and antioxidants (ascorbic acid, glutathione (GSH), glutathione peroxidase (GPx), and superoxide dismutase (SOD)) were measured using spectrophotometry. The subjects were subdivided according to PTP into three groups: patients with early, intermediate, and late PT. According to the TAC level, they were subdivided into LL-TAC, NL-TAC, and HL-TAC groups.

RESULTS

A decrease in MDA levels, SOD activity, and an increase in GSH levels and GPx activity were observed in patients with late PT compared to those with early and intermediate PT (p < 0.05). Patients with LL-TAC had lower MDA levels and higher GSH levels and GPx activity compared with the NL-TAC and HL-TAC groups (p < 0.05).

CONCLUSION

Our results have shown that in KT patients, despite the recovery of kidney function, the TAC reduced but did not normalize oxidative stress levels in long-term therapy, and the TAC effect significantly depends on the concentration used.

Relaxin and Erythropoietin Significantly Reduce Uterine Tissue Damage during Experimental Ischemia–Reperfusion Injury

Successful uterus transplantation, a potential treatment method for women suffering from absolute uterine infertility, is negatively affected by ischemia–reperfusion injury (IRI). The aim of this study is to investigate the protective effect of relaxin (RLX) or/and erythropoietin (EPO) on experimental uterus IRI. Eighty rats, randomly assigned into eight groups (n = 10/group), were pretreated with either saline, 5 μg/kg human relaxin-2, 4000 IU/kg recombinant human erythropoietin or their combination. Ischemia was achieved by clamping the aorta and ovarian arteries for 60 min, following 120 min of reperfusion and tissue sampling. For sham animals, clamping was omitted during surgery. There were no differences in tissue histological score, malondialdehyde (MDA) and superoxide dismutase (SOD) levels, myeloperoxidase (MPO) and TUNEL-positive cell count between all sham-operated rats. Pretreatment with RLX preserved normal tissue morphology, reduced MDA levels, MPO and TUNEL-positive cell count, preserved SOD activity and upregulated NICD and HES1 gene expression when compared to the control group. Pretreatment with EPO reduced MDA levels. In conclusion, pretreatment with RLX, EPO or a combination of both EPO and RLX significantly alleviates uterine tissue damage caused by IRI.

Melatonin and Glycine Reduce Uterus Ischemia/Reperfusion Injury in a Rat Model of Warm Ischemia

Ischemia/reperfusion injury (IRI) remains a significant problem to be solved in uterus transplantation (UTx). Melatonin and glycine have been shown to possess direct cytoprotective activities, mainly due to their antioxidative and anti-inflammatory properties. The aim of this study was to investigate the protective effects of melatonin and glycine and their combination on IRI in a rat model of warm ischemia. In this study, Sprague-Dawley rats were assigned to eight groups, including sham and IRI (n = 80). Melatonin and glycine alone or their combination were administered prior to 1 h of uterus ischemia followed by 1 h of reperfusion. Melatonin (50 mg/kg) was administered via gavage 2 h before IRI and glycine in an enriched diet for 5 days prior to intervention. Uterus IRI was estimated by histology, including immunohistochemistry, and biochemical tissue analyses. Histology revealed that uterus IRI was significantly attenuated by pretreatment with melatonin (p = 0.019) and glycine (p = 0.044) alone as well as their combination (p = 0.003). Uterus IRI led to increased myeloperoxidase expression, which was significantly reduced by melatonin (p = 0.004), glycine (p < 0.001) or their combination (p < 0.001). The decline in superoxide dismutase activity was significantly reduced in the melatonin (p = 0.027), glycine (p = 0.038) and combined treatment groups (p = 0.015) when compared to the IRI control group. In conclusion, melatonin, glycine and their combination significantly reduced oxidative stress-induced cell damage after IRI in a small animal warm ischemia model, and, therefore, clinical studies are required to evaluate the protective effects of these well-characterized substances in uterus IRI.

Clinicopathologic Analysis of Uterine Allografts Including Proposed Scoring of Ischemia-reperfusion Injury and T Cell-mediated Rejection-Dallas UtErus Transplant Study: A Pilot Study

BACKGROUND

Uterus transplantation (UTx) enables pregnancy in infertile women. This study describes the histopathological changes of ischemia reperfusion injury and mostly acute T cell-mediated rejection (TCMR) in UTx and proposes modification toward a working formulation grading system with associated treatments.

METHODS

Protocol and indication biopsies from 11 living and 2 deceased donor UTx recipients were analyzed. Serving as a control were 49 age-matched nontransplanted uteri. All posttransplant histopathological specimens were evaluated in a blinded fashion by 3 pathologists. Response to treatment was assessed by follow-up biopsies. Serial serum donor-specific antibody (DSA) responses were also recorded.

RESULTS

Changes attributed to ischemia reperfusion resolved within 2 weeks of UTx in most of the patients. For TCMR grading, perivascular inflammation, focal capillary disruption, and interstitial hemorrhage were added to interface inflammation, intercellular edema, stromal inflammation, and epithelial apoptotic bodies. Of the 173 protocol biopsies, 98 were classified as negative for TCMR; 34, indeterminate-borderline; 35, mild; 3, moderate; and 3, severe, 1 of which occurred in a DSA-positive recipient and also showed microvascular injury. Corticosteroids successfully treated all moderate to severe TCMR episodes. Mild TCMR was treated by increasing existing baseline immunosuppression. Indeterminate-borderline episodes were not treated. Neither ischemia reperfusion injury nor TCMR with DSA adversely affected embryo transfer.

CONCLUSION

Relying on a modified histopathological grading system, we developed a treatment strategy resulting in resolution of TCMR and successful pregnancies.

The Activation of Cannabinoid Type-2 Receptor with JWH-133 Protects Uterine Ischemia/Reperfusion-Induced Damage

INTRODUCTION

Uterus transplantation is a complex surgical procedure. Uterine ischemia/reperfusion (IR) damage occurring in this process may cause loss of function in the uterus. Cell damage must be prevented for a healthy uterine function and successful transplantation. Cannabinoids, with their increasing clinical use, are substances with strong anti-inflammatory and antioxidative effects and have a role in immune system regulation. However, their efficacy in uterine IR damage is still unknown. This study provides information on the potential applications cannabinoids agonist JWH-133 in uterine IR damage and, hence, in the transplant process.

METHODS

Rats were divided into 4 groups (n = 8), performed uterine IR, and treated 2 groups with JWH-133. After anesthesia, ischemia was applied for 1 h to the uterus while reperfusion was applied for 3 h. After the experiment, malondialdehyde (MDA) levels and phosphorylated nuclear factor-kappa B (p-NF-κB) expression were examined in the tissue samples. Also, cell damage was evaluated by histopathological imaging and TUNEL staining.

RESULTS

In the uterine IR group, NF-κB expression and MDA levels were detected at high levels. Histopathological examinations and TUNEL staining revealed extensive cell damage. On the other hand, in groups treated with JWH-133, dose-dependent NF-κB expression and MDA levels decreased (p < 0.05). Depending on the dose, the rate of surviving cells increased in TUNEL staining results.

CONCLUSION

The results showed that JWH-133 was effective in reducing uterine IR damage. Cannabinoids may be a new alternative that may be used in the transplantation process in the future.

Live birth after cervical ectopic uterus transplantation in mice

An ideal animal model is a prerequisite for the basic research of uterus transplantation. This study aimed to develop a new cervical ectopic uterus transplantation mice model, which was established by vascular anastomosis of the right common iliac artery and vein of the donor with the right common carotid artery and external jugular vein of the recipient, respectively, using the cuff method. The survival status of the transplanted uterus was assessed by macroscopic observation and histological examination after surgery, and the function of the graft uterus was tested by verifying whether the pregnancy is possible. A total of 40 transplants were performed, of which only 1 failed due to donor hemorrhage. After 26 transplants, the total operation time reduced to 52.4 ± 3.8 minutes, of which the total ischemia time took 6.6 ± 1.1 minutes. Sixty days after transplantation, all the graft uteri had a good blood supply and spontaneous contraction. The histology showed no significant difference between the transplanted uterus and the native. Embryo transfer experiments have proven that the transplanted uterus has uterine function. In conclusion, this new model is an effective and simple mice model for the studies of the scientific issues related to uterus transplantation.

Ischemia and reperfusion injury in uterus transplantation: A comprehensive review

Uterus transplantation (UTx) is the only available treatment for human beings who cannot carry children out to term. However, despite several clinical studies with a very limited number of UTx many issues have to be addressed. Up to date, there is a limited number of successful UTx with livebirth and the majority was achieved with live donors. Wide clinical application is inherently limited by the lack of organs, ischemia/reperfusion injury (IRI) as well as immunosuppression after UTx. The objective of this comprehensive literature review is to discuss these arising limitations of UTx with main focus on strategies to reduce IRI. This review showed, that usage of immunosuppressants, opioids or supplements, like amino acids, protects uterus from IRI, improving rising level of antioxidants and decreasing level of oxidative stress markers. The available data of experimental and clinical studies was compiled and will be discussed.

The Key Role of Warm and Cold Ischemia in Uterus Transplantation: A Review

Introduction: Uterus transplantation (UTx) is a promising treatment for uterine infertility that has resulted in several births since 2014. Ischemia is a key step in organ transplantation because it may lead to changes jeopardizing graft viability. Method: We performed a systematic review of animal and human studies relating to uterine ischemia. Results: We retained 64 studies published since 2000. There were 35 studies in animals, 24 in humans, and five literature reviews. Modest preliminary results in large animals and humans are limited but encouraging. In small animals, pregnancies have been reported to occur after 24 h of cold ischemia (CI). In ewes, uterine contractions have been detected after 24 h of CI. Furthermore, it has been shown in animals that uterine tolerance to CI and to warm ischemia (WI) can be increased by pharmacological products. In women, mean CI time in studies of births from uteri obtained from live donors was between 2 h 47 min and 6 h 20 min from a deceased donor; with only one birth in this case. Muscle contractions have also been demonstrated in myometrial samples from women, after six or more hours of CI. Conclusion: The uterus seems to be able to tolerate a prolonged period of CI, of at least six hours. Studies of the ischemia tolerance of the uterus and ways to improve it are essential for the development of UTx, particularly for procedures using grafts from deceased donors.

The Effects and Possible Mechanisms of Puerarin to Treat Uterine Fibrosis Induced by Ischemia-Reperfusion Injury in Rats

Background

Tissues fibrosis is caused by ischemia-reperfusion injury (IRI) and results in organ dysfunction. In this study, we aimed to investigate whether fibrosis occurs after uterine ischemia-reperfusion injury, and to investigate the effects of puerarin (Pur) on the fibrosis process in rats.

Material/Methods

Twenty-four female Wistar rats were randomly divided into three groups (8 in each group): the control group rats only received operation without uterine ischemic, the IRI group and the IRI + Pur group rats received 30-minutes ischemia and 2-weeks of reperfusion. Pur was orally administered at the onset of reperfusion. Picrosirius red staining was used to assess uterine fibrosis. Immunohistochemistry was used to detect the expression levels of transforming growth factor (TGF)-β and α-smooth muscle actin (α-SMA). Western blotting was used to evaluate the expression of chymase, TGF-β, α-SMA, and the activity of the Wnt/β-catenin pathway.

Results

Uterine fibrosis in the IRI+Pur group was significantly decreased compared with the IRI group. In addition, immunohistochemistry reveals that TGF-β and α-SMA were decreased in the IRI+Pur group compared with the IRI group. Western blotting results showed that Pur significantly suppresses the increase in chymase, α-SMA, TGF-β, and β-catenin expression levels induced by IRI.

Conclusions

The results indicated that IRI could induce uterine fibrosis and that Pur had an improvement effect on IRI-induced uterine fibrosis by downregulating the activity of mast cell chymase, TGF-β, α-SMA, and the Wnt/β-catenin pathway.

Mycophenolate mofetil attenuates uterine ischaemia/reperfusion injury in a rat model

This study evaluated the effect of mycophenolate mofetil (MMF) on uterine tissue preservation following ischaemia/reperfusion (I/R) injury. Uterine I/R injury was induced in rats by clamping the lower abdominal aorta and ovarian arteries for 30 min. Group I/R + V (n = 7) received vehicle alone while Group I/R + M (n = 7) received 20 mg/kg/day MMF. Control groups underwent sham surgery and received vehicle (Group C) or 20 mg/kg/day MMF (Group M) (n = 7 for both). Four hours after detorsion, uterine tissue 8-hydroxy-2'-deoxyguanosine (8-OHdG), glutathione, malondialdehyde (MDA), myeloperoxidase (MPO), superoxide dismutase (SOD) and serum ischaemia modified albumin (IMA) concentrations were measured. Histopathological analyses were performed. The I/R + M group showed significant reduction in serum IMA and uterine tissue 8-OHdG, MDA and MPO and significant increase in SOD concentrations compared with the I/R + V group, indicating a protective effect against I/R oxidative damage (P = 0.009, P = 0.006, P = 0.002, P = 0.003 and P = 0.009, respectively). Histopathological evaluation revealed MMF treatment resulted in significantly less tissue and cellular damage and apoptosis compared with the I/R + V group. These results indicate MMF is effective in attenuating uterine tissue damage and preventing apoptosis following uterine I/R injury, probably via anti-inflammatory and anti-oxidative action.

Remifentanil protects uterus against ischemia-reperfusion injury in rats

PURPOSE

To investigate the effects of remifentanil as an antioxidant and analyze the histopathologic, biochemical changes in experimental ischemia-reperfusion (I/R) exposed rat uteri.

METHODS

Wistar albino rats were assigned to three groups (n = 7). 2h period of ischemia was followed by 1h of reperfusion in the I/R and the I/R-remifentanil groups. After ischemia, no drug was administered in the sham and I/R groups. In the I/R-remifentanil group, remifentanil infusion (2 μg/kg/min) was started in the ischemia period, and continued until the end of reperfusion. After the ischemic and reperfusion period, the ischemic uterine horns were removed surgically for biochemical and histopathologic examination. Tissue damage scores (endometrial epithelial glandular leukocytosis, degeneration, and endometrial stromal changes) were examined. Malondialdehyde levels and catalase, superoxide dismutase enzyme activities in tissue were measured.

RESULTS

We found significantly lower epithelial leukocytosis and cell degeneration in the I/R-remifentanil group (p<0.05). Remifentanil administration significantly decreased concentrations of malondialdehyde, and increased catalase and superoxide dismutase enzyme activities (p<0.05).

CONCLUSION

Remifentanil appears to protect the uterine tissue against ischemia-reperfusion and can be used safely in uterus transplantation.

Quantification of propionaldehyde in breath of patients after lung transplantation

Oxygen-derived free radicals (ROS) have been identified to contribute significantly to ischemia-reperfusion (I/R) injury by initiating chain reactions with polyunsaturated membrane lipids (lipid peroxidation, LPO) resulting in the generation of several aldehydes and ketones. Due to their volatile nature these LPO products can be measured noninvasively in breath. We hypothesized that one of these markers, namely propionaldehyde, will be increased in lung and heart-lung transplant patients where severe oxidative stress due to I/R injury with early graft dysfunction represents one of the major postoperative complications resulting in prolonged ventilation and increased in-hospital morbidity and mortality. Expiratory air measurements for acetone, isoprene, and propionaldehyde were performed in seven patients after lung (n = 5) or heart-lung (n = 2) transplantation, ventilated patients (n = 12), and healthy volunteers (n = 17) using online ion-molecule reaction mass spectrometry. Increased concentrations of acetone (transplanted: 3812 [2347-12498]; ventilated: 1255 [276-1959]; healthy: 631 [520-784] ppbv; P < .001) and propionaldehyde (transplanted: 270 [70-424]; ventilated: 82 [41.8-142]; healthy: 1.7 [0.1-11.8] ppbv; P < .001) were found in expiratory air of transplanted and ventilated patients. Propionaldehyde resulting from spontaneous fragmentation of peroxides due to free radical-induced LPO after I/R injury in patients after lung or heart-lung transplantation can be quantified in expired breath.

The effects of tacrolimus on the activity and expression of tissue factor in the rat ovary with ischemia-reperfusion induced injury

In the present study, the effects of tacrolimus on the activity and expression of tissue factor (TF) were investigated in the ovarian ischemia-reperfusion induced injury in rats. Twenty-eight female rats (8-12 weeks, 300-350 g) were divided into four groups: control, ischemia-reperfusion (IR), tacrolimus treated before ischemia (TBI), and tacrolimus treated before reperfusion (TBR) groups (n=7/per group). TF activity was measured using Quick's method, whereas TF expression was examined immunohistochemically. TF activity was significantly higher in all treated groups compared with the control group. Strong ovarian TF expression was demonstrated in the IR and TBR groups. Moreover, tacrolimus decreased TF activity in the TBI group compared with the IR group. The decreased activity of TF in the ovarian IR model may prevent IR-related inflammation during transplant procedure.

Uterus transplantation: Experimental animal models and recent experience in humans

Uterus transplantation has been considered as an alternative management modality in the last few years for adoption or gestational surrogacy for women with absence of uterus due to congenital or acquired reasons. Surrogacy is legal in only a few countries because of ethical, social and legal issues. Up to date, a total of 11 uterus transplantation cases have been reported in which uteri were harvested from ten live donors and one donor with brain death. After unsuccessful attempt of first uterus transplantation, many studies have been conducted in animals and these experimental models enabled our knowledge to increase on this topic. First experimental studies were performed in rodents; later uterus transplantation was accomplished in sheep, pigs and rabbits. Recently, researches in non-human primates have led the experience regarding transplantation technique and success to improve. In this review, we reviewed the experimental animal researches in the area of uterus transplantation and recent experience in humans.

Tacrolimus and mycophenolate mofetil associations

Gastrointestinal risk factors after organ transplantation are prevalent, due to the chronic use of immunosuppressant. The immunosuppressive drugs such as tacrolimus/mycophenolate mofetil (TAC/MMF) association are the most commonly used therapy. TAC and MMF have been implicated in gastrotoxicity, but their direct effects, alone and combined, on intestinal cells are not completely elucidated. This study investigated the effect of TAC and MMF alone and combined on human colon carcinoma cells. Our results demonstrated that TAC and MMF individually inhibit clearly cells proliferation, enhanced free radicals, lipid peroxidation production, induced DNA lesions and reduced mitochondrial membrane potential. In this study, we also showed that the two molecules TAC and MMF combined at high concentrations amplified the cell damage. Furthermore, the TAC (5 µM) prevented cell death induced by MMF (half maximal inhibitory concentration (IC50)). Also, MMF (50 µM) induced cytoprotection in HCT116 cells against TAC (IC50) toxicity. Our findings provide additional evidence that oxidative damage is the major contribution of TAC and MMF combined toxicities. In fact, MMF and TAC exert a gastroprotective effect by modulating reactive oxygen species production. These data underscore the pleiotropic effect of TAC and MMF on HCT116 cells that play a preventive and critical role on intestinal function.