Relaxin exerts a protective effect during ischemia-reperfusion in the rat model

Protective effect of rupatadine on testicular ischemia/reperfusion injury in rats: Modulation of IL-6/STAT3, Akt/ mTOR signaling pathways

BACKGROUNDS & AIM

Spermatic cord rotation is a common problem in the field of urology, that finally results in necrosis of testicular tissue as well as male infertility. Rupatadine (RUP); a second-generation antihistaminic drug; demonstrated to have a possible protective effect in variable ischemia/reperfusion (I/R) rat models, but its role has not been studied yet in testicular I/R model.

MATERIAL & METHODS

The present study investigated RUP ability to ameliorate testicular I/R injury. The study includes four groups (6 rats/group); sham group, sham group pretreated with RUP (6 mg/kg/day; orally) for 14 days, I/R group, and RUP-I/R pretreated group.

KEY FINDINGS

The results demonstrated that I/R significantly lowered serum testosterone level and testicular tissue content of reduced glutathione. Besides, a significant elevation in malondialdehyde level, hypoxia-inducible factor-1, signal transducers and activators of transcription-3 (STAT-3), interleukin-6 (IL-6), histamine, and platelet activating factor levels along with an inhibition in testicular tissue level of vascular endothelial growth factor-A (VEGF-A) with an evident increase in caspase-3 immunoexpression in germ cells. Also, I/R significantly lowered p-AKT and mTOR testicular expression. While, RUP-I/R pretreated group showed a reversal in the testicular I/R damaging effects in a significant manner in the all the aforementioned parameters.

CONCLUSION

Based on these findings; RUP was proved to have a possible protective effect in testicular I/R injury via its antioxidant effect and its ability to modulate IL-6/STAT3, Akt/ mTOR inflammatory signaling pathways with improvement in the testicular VEGF-A level.

Phoenixin-14 may ameliorate testicular damage caused by torsion-detorsion by reducing oxidative stress and inflammation in prepubertal rats

The present study aimed to investigate the effects of Phoenixin-14 (PNX-14) on oxidative damage, inflammatory response, histopathological variations, and serum testosterone levels in testicular tissues. Forty-eight Wistar albino prepubertal male rats were divided into 4 groups (Sham, TTD, TT+PNX+TD, TTD+PNX) (n=12). The torsion period was 2 hours and the detorsion period was 24 hours in the testicular torsion/detorsion (TD) groups. A single PNX-14 (50 µg/kg) dose was injected into the rats in the TT+PNX TD group on the 90th minute of torsion, and it was injected into the rats in the TTD+PNX group at the beginning of detorsion. Oxidative damage in testicular tissues was determined based on superoxide dismutase (SOD), malondialdehyde (MDA), total antioxidant status (TAS) and total oxidant status (TOS), and inflammatory damage was determined based on TNF-α and IL-6 levels. Histopathological variations were investigated with the Periodic Acid Schiff (PAS) staining method in testicular tissues and analyzed based on Johnsen scores. Spermatogonia cells were examined immunohistochemically. Serum testosterone levels were determined with the enzyme-linked immunosorbent assay (ELISA). A significant increase in oxidative stress and inflammation parameters was determined in the TTD group when compared to the other groups (p<0.05). PNX-14 treatment led to a statistically significant decrease in these parameters and significantly repaired the TD damage in testicular tissue (p<0.05). Johnsen scoring revealed significant improvement in PNX-14 groups and an increase in spermatogonia count, supporting the biochemical findings (p<0.05). PNX-14 could be a potential therapeutic agent in testicular TD damage and further studies should be conducted to elucidate the present study findings.

Vanillic acid attenuates testicular ischemia/reperfusion injury in rats

Background

Testicular torsion is an important pediatric problem and ischemia/reperfusion injury (IRI) is involved in its etiopathogenesis. Vanillic acid (VA) is a phenolic acid has strong antioxidant properties. To our knowledge, the ability of VA to reduce testicular IRI has not been previously investigated. It was therefore aimed to evaluate whether VA had a beneficial effect against testicular IRI model in rats for the first time. Twenty-four rats were segregated into four groups: sham control, torsion/detorsion (T/D), T/D + VA (50 mg/kg and 100 mg/kg). The levels of testicular oxidative stress, inflammation, endoplasmic reticulum (ER) stress and apoptosis markers were determined using colorimetric methods. Hematoxylin–eosin staining method was used in the histopathological evaluation.

Results

Oxidative stress, inflammation, ER stress and apoptosis levels were significantly higher in testicular tissues of rats with only IRI model (p < 0.05). VA applications improved these injuries in a dose-dependent manner (p < 0.05). Moreover, it was found that the results of histological examinations supported the biochemical results to a statistically significant extent.

Conclusions

It was revealed that VA application can remove testicular IRI for the first time. This testicular protective efficacy of VA needs to be supported by more extensive preclinical studies.

Baicalein Alleviates Testicular Ischemia-Reperfusion Injury in a Rat Model of Testicular Torsion-Detorsion

Testicular torsion/detorsion-induced ischemia/reperfusion injury is partly due to the overgeneration of reactive oxygen species. Baicalein, a main bioactive constituent derived from the dried root of Scutellaria baicalensis Georgi, possesses powerful antioxidative and anti-inflammatory properties. Therefore, we designed the research to explore the possible protective effect of baicalein against testicular ischemia-reperfusion injury. Sprague-Dawley rats were randomized into 4 groups, including control, testicular ischemia-reperfusion, testicular ischemia-reperfusion+vehicle injection, and testicular ischemia-reperfusion+baicalein therapy groups. The control group received surgical exposure of the left testis without torsion-detorsion. In the testicular ischemia-reperfusion group, the left testis underwent 720° counterclockwise torsion for two hours and then was allowed detorsion. Rats in the testicular ischemia-reperfusion+vehicle injection group received intraperitoneal injection of the vehicle at detorsion. In the baicalein-treated group, the intraperitoneal administration of baicalein dissolved in the vehicle was performed at detorsion. At four hours or three months following testicular detorsion, testicular tissues were removed to detect the levels of tumor necrosis factor-alpha (TNF-α) and interleukin-1beta (IL-1β) which can recruit neutrophils into the testis, myeloperoxidase activity (an index of neutrophil infiltration in the testis), protein expression of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase in neutrophils which can catalyze reactive oxygen species production, malondialdehyde concentration (a common marker of reactive oxygen species), and spermatogenesis. Both testicular ischemia-reperfusion and testicular ischemia-reperfusion+vehicle injection significantly increased the TNF-α and IL-1β levels, myeloperoxidase activity, NADPH oxidase protein expression, and malondialdehyde concentration, while decreased spermatogenesis in ipsilateral testes. In contrast, baicalein administration remarkably reduced TNF-α and IL-1β levels, myeloperoxidase activity, NADPH oxidase protein expression, and malondialdehyde concentration and also elevated spermatogenesis in ipsilateral testes. The results of our experiment demonstrate that baicalein alleviates testicular ischemia-reperfusion injury by inhibiting TNF-α and IL-1β secretion, neutrophil infiltration in the testis, and NADPH oxidase protein expression in neutrophils to reduce reactive oxygen species production.

Oleuropein attenuates testicular ischemia-reperfusion by inhibiting apoptosis and inflammation

BACKGROUND

Ischemia-reperfusion injury (IRI) is the key reason of injury after testicular torsion and may eventually lead to male infertility. Oleuropein, a natural antioxidant isolated from Olea europaea, has shown beneficial effects in different models of ischemia. We evaluated the effects of oleuropein on testicular IRI and explored the underlying protective mechanisms.

METHODS

A mouse testicular torsion/detorsion (T/D) model and an oxygen-glucose deprivation/reperfusion (OGD/R) germ cell model were established and treated with oleuropein. H&E staining was used to evaluate testicular pathological changes. Apoptosis and apoptosis-associated protein levels in testis tissues were assessed by TUNEL staining, immunohistochemical staining and western blot. Apoptosis levels and apoptosis-associated protein levels in GC-1 were evaluated by flow cytometry, immunofluorescence and western blot. Oxidative stress levels were assessed by malondialdehyde (MDA) and superoxide dismutase (SOD) kits. Cell viability and inflammatory protein levels were evaluated by CCK-8 assay coupled with qRT-PCR.

RESULTS

Relative to the control group, SOD activity was markedly suppressed, while MDA, Bax, Caspase-3, TNF-α as well as IL-1β levels were significantly increased in the T/D model and OGD/R model. However, all of the aforementioned alterations were relieved by oleuropein treatment.

CONCLUSION

Our findings indicate that oleuropein may be a promising treatment option to attenuate testicular IRI via its anti-oxidant, anti-inflammatory as well as anti-apoptotic properties.

Salidroside Exerts Beneficial Effect on Testicular Ischemia-Reperfusion Injury in Rats

Testicular torsion-detorsion results in testicular ischemia-reperfusion injury, which is associated with overgeneration of reactive oxygen species. Salidroside, a major bioactive ingredient extracted from Rhodiola rosea, has strong antioxidant activity. The purpose of this study was to examine the effect of salidroside on testicular ischemia-reperfusion injury. Sixty rats were randomly separated into 3 experimental groups: group A = sham-operated control; group B = testicular ischemia-reperfusion; and group C = testicular ischemia-reperfusion treated with salidroside. The rats in the sham-operated control group received all surgical procedures except testicular torsion-detorsion. The testicular ischemia-reperfusion group underwent 2 hours of left testicular torsion followed by detorsion. The rats in the salidroside-treated group received the same surgical procedure as in testicular ischemia-reperfusion group, but salidroside was injected intraperitoneally at reperfusion. Testicular malondialdehyde content (a reliable index of reactive oxygen species) and protein expression of superoxide dismutase and catalase which are primary antioxidant enzymes in testes were measured at 4 hours after reperfusion. Testicular spermatogenesis was evaluated at 3 months after reperfusion. The malondialdehyde content increased significantly, while superoxide dismutase and catalase protein expression and testicular spermatogenesis reduced significantly in ipsilateral testes of testicular ischemia-reperfusion group, as compared with sham-operated control group. Therapy with salidroside significantly reduced malondialdehyde content and significantly enhanced superoxide dismutase and catalase protein expression and spermatogenesis in ipsilateral testes, as compared with testicular ischemia-reperfusion group. The present findings indicate that treatment with salidroside ameliorates testicular ischemia-reperfusion injury by reducing reactive oxygen species level by upregulating superoxide dismutase and catalase protein expression.