Remote ischemic conditioning in a rat model of testicular torsion: does it offer testicular protection?

The protective effect of pregabalin and xanthenone on testicular ischemia/reperfusion injury in rats

BACKGROUND

Torsion of the spermatic cord is a hazardous and common urologic issue. The current work evaluates the possible protective effect of pregabalin (PGB) and xanthenone (XAN) in testicular ischemia/reperfusion injury induced by testicular torsion/detorsion in rats.

MATERIALS AND METHODS

Seven groups of adult male Wistar albino rats were allocated randomly into seven groups, namely, sham control, torsion/detorsion (T/D), PGB 50 mg/kg, PGB 100 mg/kg, XAN 1 mg/kg, XAN 2 mg/kg, and PGB 50 mg/kg plus XAN 1 mg/kg groups. Serum cholesterol and testosterone levels were determined. Also, the levels of malondialdehyde (MDA), reduced glutathione (GSH), nitric oxide (NO), superoxide dismutase (SOD), tumor necrosis factor-α (TNF-α), nuclear factor kappa B (NF-қB), angiotensin (Ang) II, Ang-(1-7), and angiotensin-converting enzyme2 (ACE2) were assessed in testicular tissue. Immunohistochemical analysis of heme oxygenase-1 (HO-1) and caspase-3 was performed. Finally, the histopathological examination of the testicular tissues was performed.

RESULTS

The PGB 50 mg/kg, PGB 100 mg/kg, XAN 1 mg/kg, XAN 2 mg/kg, and PGB 50 mg/kg plus XAN 1 mg/kg groups showed a significant decrease in serum cholesterol, MDA, NO, TNF-α, NF-қB, and Ang-II levels coupled with a significant increase in both testosterone and ACE2 expression. Furthermore, all test groups showed a significant improvement in the histopathological picture with a reduction in caspase-3 and an increase in HO-1 immunoexpression in testicular tissue.

CONCLUSION

PGB and XAN may have promising effects on preventing testicular T/D injury through antioxidant, anti-inflammatory, and antiapoptotic actions.

Effect of sulforaphane on testicular ischemia-reperfusion injury induced by testicular torsion-detorsion in rats

Testicular ischemia-reperfusion induces enhanced concentration of reactive oxygen species. The increased reactive oxygen species harm cellular lipids, nucleic acids, proteins, and carbohydrates, and ultimately cause testicular injury. Sulforaphane, a kind of natural dietary isothiocyanate, exists predominantly in some cruciferous vegetables, like broccoli and cabbage. It can protect tissues from oxidative stress-induced damage. Herein, we analyzed the effectiveness of sulforaphane in treating ischemia-reperfusion injury occurring after testicular torsion-detorsion. Male rats (n = 60) were grouped as follows: sham-operated group, unilateral testicular ischemia-reperfusion group, and unilateral testicular ischemia-reperfusion group receiving sulforaphane treatment at 5 mg/kg. No testicular torsion-detorsion was performed in the sham group. Unilateral testicular ischemia-reperfusion model was created by detorsion after 2 h of left testicular torsion. In the sulforaphane-treated group, intraperitoneal sulforaphane (5 mg/kg) was administered at left testicular detorsion. Biochemical assay, Western blot, and hematoxylin and eosin staining were used to evaluate testicular malondialdehyde content (an important marker of reactive oxygen species), protein levels of superoxide dismutase and catalase (intracellular antioxidant defense mechanism), and testicular reproductive function, respectively. In testicular tissues, malondialdehyde content was significantly promoted, while protein levels of superoxide dismutase and catalase, and testicular reproductive function were significantly reduced in ipsilateral testes by testicular ischemia-reperfusion. Nevertheless, sulforaphane administration partially reversed the effect of testicular ischemia-reperfusion on these indexes. It can be concluded that sulforaphane elevates protein levels of superoxide dismutase and catalase, and suppresses reactive oxygen species content, thereby preventing ischemia-reperfusion injury in testis.

Testicular Vascularization after Pediatric Inguinal Hernia Repair: A Systematic Review and Meta-Analysis

BACKGROUND

The effect of pediatric inguinal hernia repair (IHR) on testicular vascularization remains unclear. Manipulating the spermatic cord during surgery may reduce blood flow due to edema and vasoconstriction. This can lead to testicular atrophy. The study aims to review current knowledge of testicular vascular impairment following IHR in children.

METHODS

A systematic literature search was conducted in PubMed/Medline, Embase, Cochrane Library, and Web of Science. Methodological quality was assessed using validated tools. Data were extracted, and a pooled data analysis was performed.

RESULTS

Ten studies were included in the systematic review. Six of these studies were eligible for meta-analysis. This revealed a significant decrease in testicular vascularization during the short-term follow-up (1 day-1 week) after IHR using the open surgical approach. This decrease was not present after laparoscopic intervention. There was no more increased resistance in the vessels at long-term follow-up (1 month-6 months), suggesting that the impaired vascularity is only temporary.

CONCLUSIONS

There seems to be a short-term transient vascular impairment of the testis after open IHR in children. This might be of clinical relevance to prefer the laparoscopic approach for IHR in children, even though the open approach is the gold standard, in contrast to adult IHR. The impact on testicular function and sperm quality later in life remains unclear. Comparative studies of both techniques are needed to determine if there is a significant difference in testicular vascularity. Long-term studies are necessary to assess the impact of transiently reduced vascularity on sperm quality and fertility later in life.

Pretreatment with remote ischemic conditioning attenuates testicular damage after testicular ischemia and reperfusion injury in rats

Testicular torsion is a urological emergency. However, surgical detorsion of the torsed spermatic cord can cause testicular reperfusion injury. Although remote ischemic preconditioning (RIPC) has been convincingly shown to protect organs against ischemia/reperfusion (I/R) injury, little is known regarding the effect of RIPC on testicular torsion/detorsion-induced reperfusion injury. Therefore, we aimed to evaluate the effect of RIPC on testes after testicular I/R injury in a rat model in vivo. Male Sprague-Dawley rats were randomly classified into 4 groups: sham-operated (sham), testicular I/R (TI/R), or remote liver (RIPC liver) and limb (RIPC limb) ischemic preconditioning groups. Testis I/R was induced by 3 h of right spermatic cord torsion (720° clockwise), and reperfusion was allowed for 3 hours. In the RIPC group, four cycles of 5 min of ischemia and 5 min of reperfusion were completed 30 min prior to testicular torsion. The ERK1/2 inhibitor U0126 was administered intravenously at the beginning of reperfusion (1 mg/kg). The testes were taken for the oxidative stress evaluations, histology, apoptosis, immunohistochemical and western blotting analysis. Remote liver and limb ischemic preconditioning attenuated ipsilateral and contralateral testicular damage after testicular I/R injury. For example. RIPC reduced testicular swelling and oxidative stress, lessened structural damage, and inhibited the testicular inflammatory response and apoptosis. Furthermore, RIPC treatment enhanced testicular ERK1/2 phosphorylation postI/R. Inhibition of ERK1/2 activity using U0126 eliminated the protection offered by RIPC. Our data demonstrate for the first time that RIPC protects testes against testicular I/R injury via activation of the ERK1/2 signaling pathway.

Adjuvant pharmacological and surgical therapy for testicular torsion: Current state of the art

INTRODUCTION

Although the consequences of testicular torsion (TT) have been recognized for centuries, little progress has been made to improve outcomes beyond those seen with timely scrotal exploration. Even with testicular salvage, ischemia/reperfusion injury cause significant atrophy and functional impairment. Recent efforts have sought to identify adjuvant pharmacological or surgical interventions that may attenuate these consequences. In this review, we assess the evidence supporting clinical use of these nascent interventions.

METHODS

We conducted a review of the literature published from 2000 to 2020, using the search terms "torsion", "testicular", "reperfusion", "ischemia", and "injury". Clinical and laboratory research focused on adjuvant pharmacological and surgical techniques mitigating torsion-associated injury in animal models and humans were identified. We recorded intervention timing/dose/route, and outcome timing/category through biomarkers of reperfusion injury, histology, and hormonal/reproductive function.

RESULTS

Fifty-four FDA-approved agents, plus 52 herbal/investigational drugs, were reported in animal TT models. In every study, the investigated agents showed beneficial effects on measured endpoints compared to controls. Despite these universally promising animal findings, no pharmacological trials in humans were reported. Surgical techniques studied in animal models included decompression (tunica albuginea incision, TAI), "ischemic conditioning", and hypothermia. Only three human studies on surgical adjuvant maneuvers have been reported, all involving TAI; these showed potential benefit, but the level of evidence is low.

CONCLUSION

There is preliminary evidence that adjuvant treatments may mitigate the effects of ischemia/reperfusion injury. However, the pool of investigated pharmacological agents is wide, yet remarkably shallow; most compounds have been reported in a single animal study. To advance this field, a mechanism-based approach should be used to select promising agents that can be tested systematically. This will determine treatment parameters that maximize safety, efficacy, and tolerability. Only then is it possible to move toward human trials. Adjuvant surgical methods such as TAI show promise in humans but require more robust clinical evaluation.

Effects of myricetin on testicular torsion-detorsion injury in rats

Testicular torsion is an emergency, and unless there is an urgent intervention, irreversible ischaemic damage and gonad loss occur in the testicle. We aimed to investigate myricetin's antioxidant properties as well as its protective effect against ischaemia-reperfusion (I/R) damage in the testicular torsion model. A total of 18 rats were divided into three equal groups. Group 1 was the sham group. Group 2: testicular torsion was performed, and orchiectomy was done 2 hr after detorsion. Group 3: received torsion and 1 mg/kg intraperitoneal myricetin was given 30 min before detorsion, and orchiectomy was applied 2 hr after detorsion. We evaluated tissue malondialdehyde, superoxide dismutase, and catalase levels and Johnsen Testicular Biopsy Score to show its histopathological effect. There was a statistically significant decrease in MDA values in myricetin group compared to Group 2 (p < .017). There was no significant difference in the statistical analysis of SOD and CAT values (p = .337 and p = .025). There was a statistically significant difference in testicular I/R damage in the myricetin group compared to Group 1 and Group 2 (p < .017). Myricetin treatment significantly decreased testicular tissue damage compared to the torsion group but did not reach the values close to the control group.

Sesamol Protects Testis from Ischemia-Reperfusion Injury through Scavenging Reactive Oxygen Species and Upregulating CREMτ Expression

Testicular torsion/detorsion-induced damage is considered as a typical ischemia-reperfusion injury attributed to excessive reactive oxygen species (ROS) production. ROS may regulate many genes whose expression affects cell-cycle regulation, cell proliferation, and apoptosis. The cAMP-responsive element modulator-τ (CREMτ) gene expression in the testis is essential for normal germ cell differentiation. The present study was aimed at investigating the effect of sesamol, a powerful antioxidant, on testicular ischemia-reperfusion injury and related mechanisms in an experimental testicular torsion-detorsion rat model. The type of our study was a randomized controlled trial. Sixty rats were randomly divided into the following 3 groups: (1) sham-operated control group (n = 20), (2) testicular ischemia-reperfusion group (n = 20), and (3) testicular ischemia-reperfusion+sesamol-treated group (n = 20). Testicular ischemia-reperfusion was induced by left testicular torsion (720° rotation in a counterclockwise direction) for 2 hours, followed by detorsion. Orchiectomy was performed at 4 hours or 3 months after detorsion. The testis was obtained for the analysis of the following parameters, including malondialdehyde level (a sensitive indicator of ROS), CREMτ expression, and spermatogenesis. In the testicular ischemia-reperfusion group, the malondialdehyde level was significantly increased with a concomitant significant decrease in CREMτ expression and spermatogenesis in ipsilateral testis. These results suggest that overproduction of ROS after testicular ischemia-reperfusion may downregulate CREMτ expression, which causes spermatogenic injury. Sesamol treatment resulted in a significant reduction in the malondialdehyde level and significant increase in CREMτ expression and spermatogenesis in ipsilateral testis. These data support the above suggestion. Our study shows that sesamol can attenuate testicular ischemia-reperfusion injury through scavenging ROS and upregulating CREMτ expression.