The effects of α-lipoic acid against testicular ischemia-reperfusion injury in Rats

L-Citrulline Alleviates Testicular Ischemia/Reperfusion Injury in Rats by Modulating eNOS/iNOS Induced Nitric Oxide Production, Inflammation, and Apoptosis

Testicular ischemia/reperfusion injury (TI/RI) is a significant clinical contributor to subfertility and infertility resulting from testicular torsion and subsequent detortion. Insufficient nitric oxide (NO) synthesis in TI/RI can result in endothelial dysfunction, as the vascular endothelium fails to produce sufficient NO to sustain appropriate vasodilation and blood perfusion. Many studies have found that NO plays an important role in the I/RI and its increase or decrease can affect the progression and outcome of I/RI. However, the role of NO in I/RI is controversial and complicated. NO derived by endothelial NO synthase (eNOS) shows a protective role in I/RI, while excessive NO derived by inducible NO synthase (iNOS) accelerates inflammation and increases oxidative stress, further aggravating I/RI. Nevertheless, the overexpression of eNOS may exacerbate I/RI. Here we try to investigate the new progress in the understanding of the roles of NO during I/RI. This study examined the interplay between cytotoxic and cytoprotective mechanisms underpinning NO produced from L-citrulline (L-Cit) on TI/R injured rats. Thirty-two adult Sprague-Dawley albino rats were equally randomized into the following groups: normal control group, sham group, TI/R group (3 h/4 h), and TI/R + L-Cit group (600 mg/kg) orally at 1 h before reperfusion. Compared to the TI/R-operated group, the injection of L-Cit markedly enhanced serum concentrations of reproductive hormones (p < 0.05). Elevated SOD, CAT, and GPx activity, along with reduced MDA and NO concentrations, indicated a diminished oxidative stress. The testicular levels of TNF-α, IL-1β, caspase-3, BAX, eNOS, iNOS, and NF-κB p65 were markedly reduced. Histopathological analysis corroborated the protective effect of L-Cit. The findings confirmed molecular models, demonstrating that L-Cit inhibited eNOS, iNOS, and IKKβ. The results showed that giving torsioned rats NO made from L-Cit protected them against hormonal imbalance, oxidative stress, inflammation, and apoptosis in I/RI. This makes L-Cit even more important for protecting against tissue I/RI during surgery. L-Cit not only promoted NO synthesis through eNOS activation, but it also facilitated the neutralization of iNOS production and its pathogenic NO levels during the reperfusion phase in I/R-injured rats.

Sequential administration of febuxostat and vitamin E protects against testicular ischemia/reperfusion injury via inhibition of sperm DNA damage in Wistar rats

The pathway of testicular ischemia-reperfusion injury (TIRI) has been shown to involve reactive oxygen species (ROS) generation in the ischemic phase and later phase of reperfusion. This study was therefore designed to investigate the effect of blockage of ROS in the ischemic and reperfusion phases of TIRI. Thirty male Wistar rats were grouped into five groups (n = 6 rats each): sham, torsion + detorsion (TD), febuxostat (FEB)-administered (TFD) group, vitamin E (V)-administered (TDV) group, and FEB and vitamin E-administered (TFDV) group. Blood samples (for inflammatory and hormonal assay), testicular (for oxidative stress and histopathology), and epididymal (for sperm DNA damage and indices) tissues were collected after 3 days of detorsion. The TFD and TFDV groups showed a significant reduction in XO and MDA (p < 0.001; η2 > 0.7), as well as a concomitant increase in CAT, thiols, and SOD levels when compared with the TD group (p < 0.01, η2 > 0.5). The TFD group significantly reduced all inflammatory markers (p < 0.05; η2 = 0.75). The observed increase (p < 0.05; η2 = 0.92) in LH level, in response to a low level of testosterone in the TD group, was significantly raised in TFD and TFDV groups. The observed decrease (p < 0.001) in inhibin level in the TD group was raised (p < 0.05; η2 = 0.90) in the TDV group only. A significant increase (p < 0.001) in sperm DNA damage in the TD group was significantly reduced (p < 0.05; η2 = 0.88) in all the treatment groups while the reduced sperm viability (p < 0.01) in the TD group was increased (p < 0.05) in the TFDV group only. There was an improvement in the testicular cytoarchitecture in the TFD and TFDV groups. This study showed that sequential administration of febuxostat in the ischemic phase of TT and vitamin E in the later phase of reperfusion protects the testes against TIRI via inhibition of oxidative stress, inflammation, and sperm DNA damage.

Effects of edaravone on testicular torsion-detorsion injury in rats

BACKGROUND AND OBJECTIVE

This study aimed to assess the protective ability of edaravone on testicular torsion-detorsion injury in rats.

METHODS

Eighteen adult male Sprague-Dawley rats were randomly divided into three groups: Sham group (control, n = 6); testicular torsion/detorsion (T/D group, n = 6) and T/D+edaravone (T/D+E group, n = 6). The spermatic cords of rats of the T/D group and the T/D+E group were rotated 720° in a clockwise direction and maintained for 120 min in this torsion position. Around 90 min after the torsion, edaravone at a dose of 10 mg/kg dissolved in saline was administered IP to the T/D+E group. The testicle was counter-rotated to its normal position to allow reperfusion for 4 h. Left testes of each animal were excised 240 min after beginning of reperfusion. Oxidative stress markers (TAS, TOS, SOD, and MDA) and apoptotic pathways (Caspase 3, Caspase 8, Caspase 9, Bcl-2, and Bax,) were assessed by ELISA methods. Also, testicles were subjected to the histopathologic and ultrasound examinations.

RESULTS

Ultrasound imaging showed that edaravone reduced the surface area and increased vascularization in testicles with T/D (p < 0.0001, p < 0.05, respectively). Edaravone pretreatment markedly decreased the levels of MDA, TOS, Bcl-2, Bax, Caspase 3, Caspase 8, and Caspase 9 (p < 0.0001). Also, it increased significantly TAS levels (p < 0.0001) and reduced insignificantly SOD activity. Histopathologic examinations demonstrated that edaravone significantly attenuated the histological damage caused by T/D in testicles.

CONCLUSION

Taken together, the findings indicate that pretreatment of edaravone has protective effect against testicular T/D injury.

Avanafil Mitigates Testicular Ischemia/Reperfusion Injury via NLRP3 Pathway Modulation in Rats

OBJECTIVE

In our study, the effectiveness of avanafil, a second-generation phosphodiesterase-5 (PDE5) inhibitor, on testicular torsion (TT) related ischemia/reperfusion injury via NOD-, LRR- and pyrin domain-containing protein 3 (NLRP3), which triggers inflammatory response, are studied molecularly, biochemically and histopathologically.

MATERIAL AND METHOD

This study was performed on 24 male Wistar albino rats randomized into four groups. Testicular ischemia/reperfusion (I/R) model was created for groups 2, 3 and 4. Groups 3 and 4, respectively, were administered a dose of 5 and 10 mg/kg avanafil before reperfusion by gavage. The testicles which were left in ischemia for two hours, were detorsioned for four hours. All animals were sacrificed after reperfusion. Testicular tissues were examined molecularly, biochemically and histopathologically.

RESULTS

The NLRP3, Interleukin-1β (IL-1β) and Tumor Necrosis alpha (TNF-α) mRNA expression levels were observed to be significantly increased in the I/R group compared to the healthy group (p < 0.001). After both doses of avanafil, NLRP3, IL-1β and TNF-α mRNA expression levels, which increased as a result of I/R, decreased in both avanafil groups. (p < 0.001). The greatest decrease was seen at the dose of 10 mg/kg (p < 0.001). Increased Malondialdehyde (MDA) levels due to I/R were statistically significantly decreased in both doses of avanafil (p < 0.001). Decreased Superoxide Dismutase (SOD) levels due to I/R damage increased statistically significantly in both doses of avanafil (p < 0.001).

CONCLUSION

It was found that avanafil can reduce the damage caused by testicular I/R and that it will find new applications in the future with the support of advanced experimental and clinical studies.

Usnic acid alleviates testicular ischemia/reperfusion injury in rats by modulating endoplasmic reticulum stress

Testicular torsion (TT) is a urological condition that can result in infertility in men. The etiopathogenesis of TT includes ischemia/reperfusion injury (IRI) characterized by oxidative stress (OS), inflammation and apoptosis resulting from increased levels of free radicals. Usnic acid (UA), a dibenzofuran, is one of the most common metabolites found in lichens and is known to possess powerful antioxidant properties. The aim of this study was to investigate the potential protective activity of UA in an experimental testicular IRI model for the first time. A total of 18 rats were randomly assigned to three groups (n=6): sham control, IRI and IRI+UA. The IRI groups underwent a four-hour period of ischemia and a two-hour period of reperfusion. The OS, inflammation, endoplasmic reticulum stress (ERS) and apoptosis markers in testicular tissue were evaluated using colorimetric methods. Furthermore, tissue samples were subjected to histological examination, with staining using hematoxylin and eosin. Histopathological findings supported by increased OS, inflammation, ERS and apoptosis levels were obtained in IRI group compared with sham control group. However, UA treatment restored these pathological and biochemical changes. Although this study provides the first preliminary evidence that UA may be used as a useful molecule against testicular IRI, further extensive molecular preclinical studies should be performed before clinical use is considered.

Proanthocyanidin alleviates testicular torsion/detorsion-induced ischemia/reperfusion injury in rats

Testicular torsion is an urological emergency and can lead to ischemia damage and testicular loss if not diagnosed in time. Proanthocyanidin is reported to have anti-inflammatory and antioxidant properties. The current study aimed to examine the possible effects of proanthocyanidin (P) on the testis in torsion/detorsion (T/D)-induced testicular ischemia/reperfusion (I/R) injury in rats. Forty rats were divided into four groups (n=10 for each): sham-operated (sham), I/R, I/R + P100 (100 mg/kg, 30 min before torsion), and I/R + P200 (200 mg/kg, 30 min before torsion). Testicular T/D was performed on the left testicle by 3 hours of torsion at 720° clockwise, followed by 3 hours of detorsion. In the I/R group, an increase in malondialdehyde (MDA) levels and a decrease in glutathione (GSH), vitamin C (Vit C), glutathione peroxidase (GPx), glucose-6-phosphate dehydrogenase (G6PD) values were determined compared to the sham group (p<0.001). Moreover, an increase in the expression of cleaved caspase-3 and Bcl2-associated X protein (Bax), a decrease in the expression of B-cell lymphoma 2 (Bcl-2) and proliferating cell nuclear antigen (PCNA) were detected in the I/R group (p<0.001). Histopathologically, it was determined that the Johnsen and Cosentino scores of the testicles were irregular in the I/R group (p<0.001). Proanthocyanidin treatment caused a decrease in MDA, cleaved caspase-3 and Bax levels and an increase in GSH, Vit C, GPx, G6PD, Bcl-2 and PCNA values. Additionally, Johnsen and Cosentino rearranged the scores. The present findings revealed the protective and curative effects of proanthocyanidin in organ damage due to testicular torsion/detorsion-induced ischemia/reperfusion with their antioxidative and antiapoptotic properties.

Determination of M1/M2 Macrophage Polarization in Ipsilateral and Contralateral Rat Testis Tissue Following Unilateral Torsion/Detorsion

The present study investigates the changes in M1/M2 macrophage polarization resulting from unilateral testicular torsion in the bilateral testis. The study sample included 63 male Sprague-Dawley rats, which were randomly divided into nine groups (n = 7): Control, Sham (4 h (4 h), 24 h, 7 days (7d), 14d), and Torsion/Detorsion (T/D) (4 h, 24 h, 7d, 14d). Histopathological evaluations revealed no changes in the Sham groups, while T/D was noted to cause edema, vascular occlusion, disruption of seminiferous tubule epithelial organization, germ cell abnormalities and structural anomalies in the experimental rats, the severity and extent of which increased from 4 h to 14d after T/D. The Cosentino scores used to determine the degree of histological damage were consistent with the histopathological findings in all groups, while the Johnsen scores, as a marker of spermatogenesis, were lower in the T/D groups. Seminiferous tubule diameters and germinal epithelial thickness decreased significantly in parallel with increased tubule damage in the ipsilateral testicles. Testicular torsion significantly affected sperm motility, with significant reductions observed in the T/D 7d and T/D 14d groups. A hormone profile analysis revealed decreased testosterone levels in both the Sham and T/D groups when compared to the Controls. CD68 and CD163 immunoreactivities, as M1 and M2 macrophage surface markers, were determined in the testicular tissue using the avidin-biotin-peroxidase complex method. T/D interventions caused M1/M2 macrophage polarization changes and increased M1 macrophages, particularly in contralateral testicular tissue. The increase in M1 macrophages in contralateral testicular tissue following T/D in the present study suggests that cell processes, including macrophages, may play an important role in contralateral testicular injury.

Forskolin Improves Male Reproductive Complications Caused by Hyperglycemia in Type 2 Diabetic Rats

BACKGROUND

In many diabetic patients, spermatogenesis complications are frequent causing infertility problems. This study aimed to demonstrate the effect of Forskolin on male reproductive dysfunction caused by type 2 diabetes.

MATERIALS AND METHODS

In this experimental study, type 2 diabetes was induced by a high-fat diet (HFD) for one month and then a low single dose injection (35 mg/kg) of streptozotocin (STZ) in Wistar rats. After 72 hours, rats with more than 200 mg/dl of blood glucose were considered type 2 diabetic rats. Forty rats (200-250 g) were divided into four groups (n=10) including group 1 (G1): rats with normal diet and buffer citrate (STZ solvent) injection, group 2 (G2): control type 2 diabetic rats with HFD and STZ injection, group 3 (G3): type 2 diabetic rats received phosphate buffer saline (PBS) as Forskolin solvent, and group 4 (G4): Forskolin treated diabetic rats (10 mg/kg) for 1 month.

RESULTS

In comparison to control group, in diabetic groups (G2 and G3) some parameters are increased significantly: The blood glucose (P=0.00078), testicular malondialdehyde (MDA) level and body weight (P=0.00009) and Bax gene expression (P=0.00007). Unlike, some parameters are decreased significantly: The serum level of testosterone (P=0.0009), testicular superoxide dismutase (SOD, P=0.00007) and glutathione peroxidase (GPX) levels (P=0.00008), sperm concentration (P=0.00008), motility (P=0.00009), normal morphological sperm (P=0.00008) and Bcl-2 gene expression (P=0.00009). However, in Forskolin treated group (G4) the parameters stayed close to control values that was significantly (P=0.00007) higher than in G2 and G3 groups. Therefore, treatment with Forskolin significantly improved these abnormal changes in Forskolin-treated group.

CONCLUSION

Our study demonstrates that Forskolin is an effective antidiabetic agent, which significantly improves sperm concentration, testosterone levels, and antioxidant activity in diabetic rats.

Samarcandin protects against testicular ischemia/reperfusion injury in rats via activation of Nrf2/HO-1-mediated antioxidant responses

The purpose of this study was to evaluate the effectiveness of samarcandin (SMR) in preventing testicular injury caused by ischemia/reperfusion (I/R) in rats. Rats were divided into 4 groups at random: the sham group, the T/D control group (CONT), the T/D group receiving SMR treatment at 10 mg/kg (SMR-10), and the T/D group receiving SMR treatment at 20 mg/kg (SMR-20). When compared to the CONT group, SMR improved the oxidant/antioxidant balance by reducing malondialdehyde (MDA), nitric oxide (NOx), and increasing reduced glutathione (GSH), gluta-thione peroxide (GSH-Px), and superoxide dismutase (SOD). Moreover, SMR increased the levels of the steroid hormones' testosterone (TST), follicle-stimulating hormone (FSH), and luteinizing hormone (LH) in the blood as well as controlled the inflammatory mediators; interleukin-6 (IL6), tumor necrosis factor alpha (TNF-α), and nuclear factor κB (NF-κB). Nevertheless, SMR-treated animals showed a considerable downregulation of the apoptotic marker caspase-3. The T/D-induced histopathological changes were reduced and Proliferating Cell Nuclear Antigen (PCNA) protein expression was enhanced by SMR. These effects are associated with upregulation of testicular (Nuclear factor erythroid 2-related factor 2 (Nrf2), Heme oxygenase-1 (HO-1), and downregulation of NF-κB mRNA expression levels. These findings suggest that SMR may be able to prevent T/D-induced testis damage by mainly regulating the expression of Nrf2 and NF-B, which seems to mediate its promising antioxidant, anti-inflammatory and antiapoptotic effects seen in this study.

Rescuing fertility during COVID-19 infection: exploring potential pharmacological and natural therapeutic approaches for comorbidity, by focusing on NLRP3 inflammasome mechanism

The respiratory system was primarily considered the only organ affected by Coronavirus disease 2019 (COVID-19). As the pandemic continues, there is an increasing concern from the scientific community about the future effects of the virus on male and female reproductive organs, infertility, and, most significantly, its impact on the future generation. The general presumption is that if the primary clinical symptoms of COVID-19 are not controlled, we will face several challenges, including compromised infertility, infection-exposed cryopreserved germ cells or embryos, and health complications in future generations, likely connected to the COVID-19 infections of parents and ancestors. In this review article, we dedicatedly studied severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2) virology, its receptors, and the effect of the virus to induce the activation of inflammasome as the main arm of the innate immune response. Among inflammasomes, nucleotide oligomerization domain-like receptor protein, pyrin domain containing 3 (NLRP3) inflammasome pathway activation is partly responsible for the inflicted damages in both COVID-19 infection and some reproductive disorders, so the main focus of the discussion is on NLRP3 inflammasome in the pathogenesis of COVID-19 infection alongside in the reproductive biology. In addition, the potential effects of the virus on male and female gonad functions were discussed, and we further explored the potential natural and pharmacological therapeutic approaches for comorbidity via NLRP3 inflammasome neutralization to develop a hypothesis for averting the long-term repercussions of COVID-19. Since activation of the NLRP3 inflammasome pathway contributes to the damage caused by COVID-19 infection and some reproductive disorders, NLRP3 inflammasome inhibitors have a great potential to be considered candidates for alleviating the pathological effects of the COVID-19 infection on the germ cells and reproductive tissues. This would impede the subsequent massive wave of infertility that may threaten the patients.

Effect of ferulic acid on testicular damage caused by torsion-detorsion in rats

Testicular torsion is twisting of the spermatic cord around its axis, which impairs blood flow and causes ischemia and formation of free radicals. Ferulic acid is a phenolic acid of the hydroxycinnamic family that is found in the seeds and leaves of plants; it is present in substantial amounts in fruits and vegetables. We investigated the protective effect of ferulic acid on experimental testicular torsion in rats. Animals were divided randomly into five groups: control, ethyl alcohol, torsion, torsion-detorsion, and torsion-detorsion + ferulic acid. Histopathology was assessed using hematoxylin and eosin, and periodic acid-Schiff staining. Tissues were assessed using TUNEL, active caspase-3, myeloperoxidase and inducible nitric oxide synthase immunostaining. Biochemical changes were assessed using assays for superoxide dismutase, malondialdehyde, glutathione peroxidase and glutathione. Ferulic acid reduced the levels of free radicals and increased the levels of antioxidants. Ferulic acid also reduced histopathological changes and germ cell differentiation in the testis following torsion-detorsion. Ferulic acid should be investigated further as a potential treatment for sequelae of torsion-detorsion injury.

Protective effect of cerium oxide on testicular function and oxidative stress after torsion/detorsion in adult male rats

Testicular torsion (T)/detorsion (D) can cause testicular injury due to the rotation of the spermatic cord and its vessels, therefore it represents an urological emergency that is surgically treated. Oxidative damage occurs in the testis and distant organs because of the overproduction of free radicals and overexpression of proinflammatory cytokines by reperfusion after surgery. Cerium oxide (CeO2) nanoparticles, a material also known as nanoceria, have regenerative antioxidant properties on oxidative stress. The present study aimed to investigate the effects of nanoceria on testis tissues in testicular T/D in rats. A total of 24 rats were equally and randomly divided into four groups: Control, CeO2, T/D and CeO2-T/D groups. Left inguinoscrotal incision was performed in the control group. In the CeO2 group, 0.5 mg/kg CeO2 was given intraperitoneally 30 min before inguinoscrotal incision. In the T/D group, unilateral testicular T/D was performed through an inguinoscrotal incision and rotating the left testis 720˚ clockwise, which was then left ischemic for 120 min, followed by 120 min of reperfusion. In the CeO2-T/D group, 0.5 mg/kg CeO2 was given intraperitoneally 30 min before testicular T/D. At the end of the experiment, testis tissues were removed for histopathological and biochemical examinations. The samples were histologically examined, Glutathione-s transferase (GST), catalase (CAT), paraoxonase (PON) activities and malondialdehyde (MDA) levels were measured via biochemical analysis methods, while the expression levels of p53, Bax and Bcl-2 were detected using immunohistochemistry. The present results revealed statistically significant inter-group differences in PON, CAT and GST activities and MDA levels. GST, CAT and PON activities were significantly higher, whereas MDA levels in the CeO2-T/D group were significantly lower compared with those in the T/D group. The T/D group had increased Bax and decreased Bcl-2 expression levels in their seminiferous tubules compared with the control and CeO2 groups. CeO2 treatment led to downregulation of Bax and upregulation of Bcl-2. The expression of p53 was high in the T/D group compared with that in the control and CeO2 groups, and was upregulated in all germinal cells. However, compared with that in the T/D group, p53 expression was significantly decreased in the CeO2-T/D group. The testicular injury score significantly increased in the CeO2-T/D group compared with the control and CeO2 groups. Rats in the CeO2-T/D group demonstrated significantly milder tissue lesions compared with those in T/D group. The present findings indicated that nanoceria may protect testis in rats against the harmful effects of T/D. Further studies are required to evaluate how CeO2 reduces oxidative stress and cell death in testis tissue that underwent T/D-related injury.

Oridonin attenuates hind limb ischemia-reperfusion injury by modulating Nrf2-mediated oxidative stress and NLRP3-mediated inflammation

ETHNOPHARMACOLOGICAL RELEVANCE

Oridonin (Ori), extracted from Isodon rubescens (Hemsl.) H.Hara, is a well-known traditional Chinese herbal medicinal product that possesses antioxidant and anti-inflammatory activities. Oxidative stress and inflammation are the main pathophysiological mechanisms in hindlimb IR injury. However, whether Ori has a protective effect on hind limb IR injury is unknown.

AIM OF THE STUDY

The present study was designed to determine the effect of Ori on hindlimb IR injury and its relationship with oxidative stress and inflammation.

MATERIALS AND METHODS

The hind limb IR injury model in mice was used to evaluate the protective effect and related mechanisms of Ori. Forty-eight C57BL/6 mice (n = 12 per group) were randomly divided into four groups: Sham group; IR group; IR + Ori (10 mg/kg) group and IR + Ori (20 mg/kg) group. Mice in the IR and IR + Ori groups were subjected to hindlimb IR injury, while mice in the Sham group were subjected to no hindlimb IR injury. HE staining, Masson's staining, TTC staining, DHE staining, TUNEL staining, western blotting analysis and quantitative real-time PCR were employed to explore the mechanisms by which Ori exerts a protective effect on a classical hindlimb IR model in mice.

RESULTS

We found that Ori pretreatment prevented muscle damage and decreased cell apoptosis levels compared with the vehicle control. Moreover, the SOD2, CAT, MDA and ROS levels in muscle showed that Ori could significantly reduce oxidative stress in hindlimb IR mice, while the IL-1β and TNF-α levels in muscle showed that Ori could significantly attenuate IR-induced inflammation. We also found that Ori could increase the expression of Nrf2 and its downstream protein HO-1 and inhibit the expression levels of NLRP3-related proteins (NLRP3, ASC and Caspase-1) in vivo.

CONCLUSIONS

Our study suggested that Ori has a protective effect on hindlimb IR injury, which may be related to Nrf2-mediated oxidative stress and NLRP3-mediated inflammasome activation.

Effects of Lipoic Acid on Ischemia-Reperfusion Injury

Ischemia-reperfusion (I/R) injury often occurred in some pathologies and surgeries. I/R injury not only harmed to physiological functions of corresponding organ and tissue but also induced multiple tissue or organ dysfunctions (even these in distant locations). Although the reperfusion of blood attenuated I/R injury to a certain degree, the risk of secondary damages was difficult to be controlled and it even caused failures of these tissues and organs. Lipoic acid (LA), as an endogenous active substance and a functional agent in food, owns better safety and effects in our body (e.g., enhancing antioxidant activity, improving cognition and dementia, controlling weight, and preventing multiple sclerosis, diabetes complication, and cancer). The literature searching was conducted in PubMed, Embase, Cochrane Library, Web of Science, and SCOPUS from inception to 20 May 2021. It had showed that endogenous LA was exhausted in the process of I/R, which further aggravated I/R injury. Thus, supplements with LA timely (especially pretreatments) may be the prospective way to prevent I/R injury. Recently, studies had demonstrated that LA supplements significantly attenuated I/R injuries of many organs, though clinic investigations were short at present. Hence, it was urgent to summarize these progresses about the effects of LA on different I/R organs as well as the potential mechanisms, which would enlighten further investigations and prepare for clinic applications in the future.

Cross-link between mitochondrial-dependent apoptosis and cell cycle checkpoint proteins after experimental torsion and detorsion in rats

The current study assessed the cross-link between mitochondria-related apoptosis and cell cycle machinery systems during ischemia and reperfusion in a rat model of testicular torsion and detorsion. The Wistar male rats were divided into control, 1 h, 2 h, 4 h and 8 h testicular torsion-induced, and 1 h, 2 h, 4 h and 8 h testicular detorsion-induced groups. The Johnson's score was analyzed. The mRNA and protein contents of Bcl-2, Bax, Caspase-3, Cyclin D1, Cdk4, P21 and P53 were investigated by sqRT-PCR and immunohistochemical staining, respectively. The apoptosis index was analyzed by TUNEL staining. The mRNA levels of bax, p53, p21 and cyclin D1 were increased, and the mRNA levels of bcl-2 and cdk4 were decreased in torsion and reperfusion-induced groups, time-dependently. The caspase-3 mRNA was increased in torsion-induced and diminished in detorsion-induced groups. A time-dependent reduction in Bcl-2⁺, Caspase-3⁺, Cyclin D1⁺, Cdk4⁺ and P53⁺ and increment in P21⁺ cells distribution per mm² of tissue were revealed after torsion and detorsion. The apoptosis index was increased after torsion and decreased after detorsion. In conclusion, torsion-induced severe DNA damage stimulates the cyclin D1, p53 and p21 mRNA expression while more than 8 h is needed to reveal them as protein content in testicular tissue. About detorsion, decreased Cyclin D1 and Cdk4 proteins and the P53-induced transcriptional effect on p21 expression, stimulates the p21 bind to cdk4 and consequent failure in Cyclin D1/Cdk4 complex formation. This situation in association with apoptotic genes results in spermatogenesis failure.

Effects of hypothermia and pentoxifylline on the adnexal torsion/detorsion injuries in a rat testis model

This study was designed to investigate the effects of separate and combined administration of hypothermia and pentoxifylline to preserve the effects on the testicles in an experimental model of testicular torsion/ detorsion injuries in rats. Forty male adult Wistar rats were randomly divided into five groups, control, torsion/detorsion (TD), torsion/detorsion/hypothermia (TD+ICE), torsion/detorsion received of pentoxifylline (40mg/kg, ip) (TD+PTX) and torsion/detorsion/hypothermia/PTX (TD+ICE+PTX). Left testicular torsion (TT) was performed for 4 and half hours, and ice fragments have been used at the beginning of torsion. After the reperfusion period (a week), oxidative maker's serum levels, testosterone hormone, sperm parameters, and histopathological and gene expression evaluations have been performed. Significant adverse changes were observed in the TD group for histological variables, sperm count, oxidative marker, testosterone hormone, Bax, BCL2 and caspase-3 expression. The parameters studied in the group receiving PTX improved in comparison with the TD group, while macroscopical parameters of both the hypothermia and PTX+ICE groups were not different compared with the TD group. The results revealed that PTX, as an antioxidant component, was protective against testicular torsion, while hypothermia and hypothermia plus PTX did not exhibit this property, which may have been due to the duration of hypothermia (4 hr) or reperfusion period.

The effects of CoQ10 supplement on matrix metalloproteinases, oxidative DNA damage and pro-inflammatory cytokines in testicular ischaemia/reperfusion injury in rats

We aimed to study the effect of coenzyme Q10 on pro-inflammatory cytokine, matrix metalloproteinase, oxidative DNA damage, caspase 3 and caspase 8 in ischaemia/reperfusion injury led to by testicular torsion/detorsion. Our research is a controlled experimental animal research using rats. This study was conducted with fifty-six adult male Albino Wistar rats. Interleucine-1β, 2, 6, 10, tumour necrosis factor-α, matrix metalloproteinase-2, 3, 9, 13, tissue inhibitor matrix metalloproteinase-1, 2, malondialdehyde and leucocyte 8-hydroxy-2-deoxy guanosine/10⁶ deoxyguanosine was detected in serum and tissue samples. In addition, immunohistochemical analysis of caspase 2 and caspase 8 was performed. In testicular I/R injury, especially 24 hr after detorsion, oxidative damage pro-inflammatory cytokines and matrix metalloproteinases were increased. At the coenzyme Q10 group, a meaningful decrease was observed in these parameters. In addition, a decrease in the expression of caspase3 and caspase 8 was viewed in coenzyme Q10-treated groups. The coenzyme Q10 has beneficial effects on oxidative damage, pro-inflammatory cytokine levels, remodelling of extracellular matrix and apoptosis in testicular I/R injury.

Protective effect of hypothermia and vitamin E on spermatogenic function after reduction of testicular torsion in rats

This study was designed to investigate the protective effect of hypothermia and vitamin E on spermatogenic function after reduction of testicular torsion in rats. Ninety-six pure inbred male SD rats were divided into group A, B, C and D according to the principle of body weight and birth similarity, with 24 rats in each group. Four groups of rats were respectively twisted on the left testis to establish unilateral testicular torsion rats. Rats in groups A, B, C, D were respectively given normal saline, hypothermia therapy, vitamin E therapy, and hypothermia and vitamin E therapy. The superoxide dismutase (SOD) activity and malondialdehyde (MDA) content of the four groups were detected, and the correlation levels of inflammatory factors IL-1β, hs-CRP and related sex hormones luteinizing hormone (LH), follicle-stimulating hormone (FSH), total testosterone (T) were detected by ELISA. Apoptosis of spermatogenic cells of testis in the four groups was detected by flow cytometry. SOD activity and MDA content in groups B, C and D were significantly higher than those in group A, MDA content was significantly lower than that in group A (P<0.05), SOD activity in group D was higher than that in groups B and C, while MDA content was lower than that in groups B and C (P<0.05). The levels of IL-1β and hs-CRP in group A were much higher than those in groups B, C and D (P<0.05). LH and FSH levels in group A were significantly higher than those in groups B, C and D (P<0.05), and in group D were significantly lower than those in groups B and C (P<0.05). Apoptosis rate of spermatogenic cells in group A was significantly higher than that in groups B, C and D (P<0.05). Hypothermia combined with vitamin E can reverse testicular injury in rats and reduce the apoptosis rate of spermatogenic cells.

Amelioration of cyclosporine-induced testicular toxicity by carvedilol and/or alpha-lipoic acid: Role of TGF-β1, the proinflammatory cytokines, Nrf2/HO-1 pathway and apoptosis

Cyclosporine is an immunosuppressive agent that is used to prevent organ rejection after organ transplantation. Due to the widespread use of this type of surgery, the effect of cyclosporine on reproduction and fertility should have a specific interest. Our aim was to assess the effect of carvedilol and/or alpha-lipoic acid on cyclosporine-induced testicular toxicity in rats. Sixty male Wistar rats were divided into six equal groups: Control; cyclosporine; cyclosporine + carvedilol; cyclosporine + alpha-lipoic acid; cyclosporine + carboxymethyl cellulose; and cyclosporine + carvedilol +alpha-lipoic acid. Food intake, testis weight, testicular functions, serum testosterone, luteinizing hormone and follicle-stimulating hormone were measured. Also, testicular tissue 3 β-hydroxysteroid dehydrogenase, 17 β- hydroxysteroid dehydrogenase, paroxonase-1, proinflammatory cytokines, transforming growth factor beta-1, nuclear factor (erythroid-derived 2)-like 2 (Nrf2)/Heme oxygenase-1 (HO-1) content and sperm characteristics were determined. Parts of the testes were subjected to histopathological and electron microscopic examination. The carvedilol/alpha-lipoic acid combination restored the food intake, testicular weight and functions, sperm characteristics, hormonal profile and the antioxidant defences compared to the use of each of these drugs alone. Also, this combination significantly ameliorated inflammation (P < .05) and induced significant increase in tissue Nrf2/HO-1 content (P < .05) and significant improvement of the histopathological and electron microscopic picture (P < .05) compared to the use of each of these drugs alone. So, carvedilol/alpha-lipoic acid combination might represent a novel therapeutic strategy to ameliorate testicular damage induced by cyclosporine.

Paeonol protects against testicular ischaemia-reperfusion injury in rats through inhibition of oxidative stress and inflammation

Ischaemia-reperfusion (IR) is the most common form of testicular injury that results in oxidative damage and inflammation ending by subinfertility. Paeonol, a natural phenolic compound, exhibits antioxidant and anti-inflammatory effects. Thus, the present study investigated the role of paeonol in rat testicular IR injury. Thirty adult Wistar rats were randomly divided into five groups; sham, sham treated with paeonol, IR injury, and IR pre-treated with paeonol at low and high doses. Serum testosterone and testicular levels of malondialdehyde and reduced glutathione (GSH) besides superoxide dismutase (SOD) activity were determined. Gene quantifications for tumour necrosis factor-α (TNF-α), hypoxia-inducible factor-1α (HIF-1α) and heat shock protein 70 (HSP70) were also assessed. Histopathological pictures and the immunohistochemical expression of testicular nuclear factor erythroid 2-related factor 2 (Nrf2), interleukin-1β (IL-1β) and interleukin-6 (IL-6) were shown. Pre-treatment with paeonol prevented the drop in serum testosterone, alongside with improvement of testicular malondialdehyde and GSH levels plus SOD activity. Paeonol regained the normal spermatogenesis with prevention of IR-induced increase in TNF-α, HIF-1α and HSP70 gene expression besides IL-1β and IL-6 immunostaining and reduction in Nrf2 protein expression. Paeonol exerted a dose-dependent beneficial effect on testicular IR injury. This effect was achieved by its antioxidant and anti-inflammatory effects.

Protective effect of alpha-lipoic acid on di-(2-ethylhexyl) phthalate-induced testicular toxicity in mice

Phthalates are synthetic chemicals, widely used as plasticizers due to their flexibility in plastics. Human populations may be exposed to phthalates through direct contact or environmental contamination. Most studies have focused on the effects of phthalates on the reproductive tract and have classified these compounds as endocrine disruptors. In this study, we aimed to investigate the possible oxidative damage induced by di-(2-ethylhexyl) phthalate (DEHP) in the mouse testis and to evaluate the regulatory effects of alpha-lipoic acid (LA). For this purpose, forty male mice were divided into four experimental groups. Group I received normal saline (2 mL/kg; p.o.) and corn oil (5 mL/kg; p.o.) as the control group, group II received DEHP (2 g/kg; p.o.), group III received DEHP and LA (20 mg/kg; p.o.), and group IV was treated with LA alone; treatments continued for 2 weeks. The glutathione level (GSH), as well as glutathione peroxidase (GPx), superoxide dismutase (SOD), and catalase (CAT) activities, was determined in mice. In addition, serum concentrations of follicle-stimulating hormone (FSH), luteinizing hormone (LH), testosterone, interleukin-1β (IL-1β), and tumor necrosis factor-alpha (TNF-α) were measured. Nitric oxide (NO) level, malondialdehyde (MDA) level, sperm characteristics, and histological changes of the testes were also evaluated. The results showed that 2 g/kg of DEHP could significantly decrease the sperm motility. Based on our findings, DEHP significantly reduced the production and count of sperms; these toxic effects were associated with alterations in the serum hormone levels. In the DEHP group, a significant reduction was reported in the serum testosterone, FSH, and LH levels. LA improved DEHP-induced changes in hormonal levels and sperm index. According to our findings, treatment with DEHP triggered histopathological changes and oxidative stress, which were normalized by LA pretreatment. In conclusion, DEHP disrupts the testicular function in rats, at least partly through induction of oxidative stress. On the other hand, LA exhibits potential protective effects on testicular toxicity induced by DEHP.

The effects of verapamil and heparin co-administration on sperm parameters and oxidative stress in prevention of testicular torsion/detorsion damage in rats

In this research, the impacts of combined administration of verapamil and heparin on testicular torsion damage were examined. In this experimental study, 30 sexually mature male Wistar albino rats were divided into five equal groups haphazardly (n = 6): Group 1 was the sham group. In group 2, a 2-hr testicular torsion was induced, and thereafter, detorsion was done. Rats in group 3 and group 4 experienced an identical surgical procedure like group 2, but verapamil and heparin were administered in 0.3 mg/kg and 800 IU/kg doses respectively, and in group 5, a combination of verapamil and heparin were administered. Intraperitoneal drug injection in all treatment groups was done 30 min before testicular detorsion. Testicular torsion significantly changed sperm parameters, oxidative stress biomarkers and Cosentino's histological score compared to the sham group (p < .05). All treatment groups reduced testicular damage by decreasing oxidative stress and improving sperm parameters, but heparin and co-administration of verapamil and heparin were significantly better than verapamil injection alone. However, heparin injected group was more effective than other treatment groups (p < .05). Overall, an anticoagulant like heparin is more effective than a calcium channel blocker such as verapamil, and it is more likely to reduce testicular torsion injuries.

Protective effects of persian honey, Apis Mellifera Meda Skorikov on side effects of chemotherapy and ischemia/reperfusion induced testicular injury

Introduction The aim of the present study was to survey the protective effect of pretreatment with Persian honey on amelioration of side effects of chemotherapy and ischemia/reperfusion induced testicular injury. Materials and methods Forty adult's male wistar rats were divided into four groups of ischemia-reperfusion (IR), honey + ischemia-reperfusion (HIR), Busulfan (B) and Busulfan intraperitoneally+ honey (BH). The seminiferous tubules were rated for their modified spermatogenesis index (SI) by Johnsons score. Detection of single- and double-stranded DNA breaks at the early stages of apoptosis was performed using the in-situ cell death detection kit. Total serum concentration of Follicle-stimulating hormone (FSH) , Luteinizing hormone (LH) and testosterone was measured using ELISA. All data were expressed as mean ± SD and significance was set at p≤0.05. Results Honey improved SI in the HIR and BH groups and serum levels of FSH and LH in the BH and HIR groups (p<0.001). Also, serum levels of testosterone were significantly higher in BH and HIR groups. But, apoptotic cells in IR and B groups significantly increased (p<0.001), while in HIR and BH groups, the number of apoptotic cells decreased and the positive cells of TUNEL (TdT-mediated dUTP-X nick end labelling) staining were detected in spermatocytes and spermatid. Discussion Pretreatment with honey protect testis against chemotherapy and testicular IR injury, increase FSH and LH and testosterone and decrease the cellular damage and apoptosis. Honey can decrease the side effects of chemotherapy on reproductive system and prevent sterility.

Alpha Lipoic Acid: A Therapeutic Strategy that Tend to Limit the Action of Free Radicals in Transplantation

Organ replacement is an option to mitigate irreversible organ damage. This procedure has achieved a considerable degree of acceptance. However, several factors significantly limit its effectiveness. Among them, the initial inflammatory graft reaction due to ischemia-reperfusion injury (IRI) has a fundamental influence on the short and long term organ function. The reactive oxygen species (ROS) produced during the IRI actively participates in these adverse events. Therapeutic strategies that tend to limit the action of free radicals could result in beneficial effects in transplantation outcome. Accordingly, the anti-oxidant α-lipoic acid (ALA) have been proved to be protective in several animal experimental models and humans. In a clinical trial, ALA was found to decrease hepatic IRI after hepatic occlusion and resection. Furthermore, the treatment of cadaveric donor and recipient with ALA had a protective effect in the short-term outcome in simultaneous kidney and pancreas transplanted patients. These studies support ALA as a drug to mitigate the damage caused by IRI and reinforce the knowledge about the deleterious consequences of ROS on graft injury in transplantation. The goal of this review is to overview the current knowledge about ROS in transplantation and the use of ALA to mitigate it.

Effects of folic acid administration on testicular ischemia/reperfusion injury in rats

PURPOSE

To determine the effect of folic acid (FA) on experimental testicular ischemia/reperfusion (I/R) in rats.

METHODS

Sixty male Wistar rats were randomly divided into 6 groups. The control group received physiologic saline orally. The sham-operated group received physiologic saline orally then exposed to midline laparotomy without clamping the IR. The I/R rats received oral gavage of the saline then subjected to 1h ischemia /24h reperfusion, period. In folic acid (2mg/kg+IR) rats received oral gavage of the FA (2mg/kg) then subjected to 1h I/24h R. groups 5-6 received FA (5 and 10 mg/kg), then subjected to 1 h I/24 h, respectively. At the end of the study, semen samples were collected for spermatozoa characteristics. The left testis was removed for histological analysis and superoxide dismutase (SOD), malondialdehyde (MDA) and glutathione peroxidase (GPx) measurement.

RESULTS

Spermatozoa mobility, mortality (%) significantly decreased in I/R group (P<0.05). Dose dependent increase observed on spermatozoa mobility, mortality (%) using different levels of the FA (2, 5 and 10 mg/kg) treated rat (P<0.05). Tissue MDA levels significantly increased in I/R rat (P<0.05) while FA (2, 5 and 10mg/kg) in a dose dependent manner decreased I/R-induced MDA (P<0.05). Experimental I/R significantly decreased SOD and GPx activity (P<0.05). Administration of the FA (2, 5 and 10mg/kg) significantly increased tissue SOD and GPx activity in I/R rat (P<0.05). Seminiferous tubules degenerated and loss of spermatogenesis with few spermatocytes was observed in degenerated testis tubules in I/R rat. Orally administration of the FA (5 and 10 mg/kg) improved testis characteristics with few normal seminiferous tubules and spermatocyte in seminiferous tubules in experimental I/R-induced rat.

CONCLUSION

The treatment of folic acid had a benefit effect against ischemia-reperfusion.

Antioxidants in experimental ischemia-reperfusion injury of the testis: Where are we heading towards?

Testicular torsion (TT) is a medical emergency that primary affects newborns and young adolescents. It causes testicular injury due to the torsion of the spermatic cord and its components, initially in the venous blood flow and finally in the arterial blood flow. Prompt diagnosis and early surgical management are necessary in managing this urgent situation. The process of the pathophysiological events in ischemia-reperfusion is multifactorial and deals with the perception of the oxidative stress responsible for the consequences of ischemia/reperfusion (I/R) stress following TT. Duration and severity of torsion also play a significant role in the oxidative stress. A detrimental result of the defense system of the testes takes place resulting finally in testicular atrophy and impaired function. Antioxidant factors have been experimentally studied in an effort to front this state. They have been classified as endogenous or exogenous antioxidants. Endogenous antioxidants comprise a structure of enzymic enzymatic and non-enzymic enzymatic particles presented within cytoplasm and numerous other subunits in the cells. Exogenous antioxidants include a variety of natural and pharmaceutical agents that may prevent or ameliorate the harmful effects of I/R injury. In this study we review those factors and their ability to enhance the oxidative status of the testis. A feature insight into where we are heading is attempted.

The effects of melatonin and colchicine on ischemia-reperfusion injury in experimental rat testicular torsion model

PURPOSE

The aim of the present study is to investigate the efficiency of colchicine and melatonın in an experimental rat testicular torsion model in the light of histological and biochemical data.

METHODS

A total of 34 Wistar albino male rats were randomly divided into 5 groups as: Group C (control, n=6), Group S (sham; underwent only left scrotal exploration, n=7), Group TD (torsion and detorsion; 6h of ischemia and 7days of reperfusion, n=7), Group TD/M (TD+Melatonin; 6h of ischemia and 7days of reperfusion and 7days of 17mg/kg intraperitoneal melatonin per day, n=7), group TD/Col (TD+Colchicine; 6h of ischemia and 7days of reperfusion and 7days of 1mg/kg oral colchicine per day, n=7). Histopathologic evaluation of seminiferous tubule deterioration was performed by Johnsen's scoring system. Total antioxidant status (TAS), total oxidant status (TOS), IL-6, TNF alpha levels were analyzed in each group.

RESULTS

The histopathologic scores, total antioxidant status (TAS), total oxidant status (TOS), IL-6, TNF alpha levels in groups C and TD/Col were significantly lower than groups TD and TD/M (P<.001).

CONCLUSION

Our study results revealed that colchicine reduced testicular ischemia-reperfusion injury in experimental rat testis torsion model. Although detorsion of testis is crucial for the preserving the testicular viability, antioxidant and anti-inflammatory treatment modalities like colchicine might help to reduce ischemia-reperfusion injury in detorsed testis.

Medical perspective in testicular ischemia-reperfusion injury

Testicular torsion or torsion of the spermatic cord is one of the most serious urological conditions. It causes testicular injury, which potentially leads to male subfertility. The turning of the spermatic cord and spermatic structures around themselves results in biochemical and histological changes; however, following testicular detorsion, tissues undergo reperfusion that causes more severe damage than that induced by ischemia. Since the primary causes of testicular damage are reactive oxygen species production, an increase in intra-mitochondrial calcium concentration and an increased rate of cellular apoptosis, different medications may potentially be effective. It seems that several medications, experimentally and sometimes clinically, serve an adjuvant role in the cellular damage that occurs following ischemia-reperfusion. Antioxidants, calcium channel blockers, phytotherapeutical medicinals, anaesthetics, hormones and platelet inhibitors may potentially create a solid basis for an adjuvant restoring therapy and ameliorate testicular function following torsion. The current study aimed to review the relevant literature and discuss the actions of a number of molecules that may protect the testes during ischemia/reperfusion injury.

Honey improves spermatogenesis and hormone secretion in testicular ischaemia-reperfusion-induced injury in rats

This study was conducted to survey the protective effect of pre-treatment with Persian honey during post-ischaemia reperfusion on ischaemia-reperfusion (IR)-induced testis injury. Animals were divided into four groups of IR, honey + ischaemia- reperfusion (HIR), vitamin C + ischaemia- reperfusion (VIR) and carbohydrates + ischaemia- reperfusion (CIR). The testes were examined for spermatogenesis index. Detection of single- and double-stranded DNA breaks at the early stages of apoptosis was performed. Total serum concentration of FSH, LH and testosterone was measured using ELISA. All data were expressed as mean ± SD in each group, and significance was set at p ≤ .05. Spermatogenesis index was significant in the HIR group (p < .001). Serum levels of FSH and LH were significantly higher in the CIR and HIR groups. Serum levels of testosterone were significantly higher in VIR and HIR groups. Apoptotic cells in IR and CIR groups increased significantly statistically (p < .001), while in HIR and VIR groups, the number of apoptotic cells decreased and the positive cells of TUNEL staining were detected in spermatocytes and spermatid. The present study indicates that honey decreases the cellular damage and apoptosis during testicular I/R injury, with significant protective effects on reproductive hormone production.

Mannitol has a protective effect on testicular torsion: An experimental rat model

OBJECTIVE

Testicular torsion is an emergency condition that causes testicular injury. Any treatment opportunity reducing the destructive effect of testicular torsion is important for the future life of patients. In this experimental study we investigated the protective effect of mannitol on ischemia-reperfusion (I/R) injury in a rat testes torsion model.

METHOD

In total, 32 male Sprague Dawley rats were included. Four experimental groups included eight rats each. Group A was a sham group in which the right testis was brought out through a scrotal incision and then replaced in the scrotum without torsion. In Group B, the right testis was torsioned, by rotating 720° clockwise and fixed to the scrotum with no treatment. In Group C, the same testicular torsion process was performed with saline infusion just after testicular torsion. In group D, mannitol infusion was used just after testicular torsion. Testicles were detorsioned after 3 h and left inside for more than 2 h before orchiectomy. Histopathological, immunohistochemical, and biochemical analyses were performed.

RESULTS

Testicular architecture was disturbed significantly in the torsion groups without mannitol infusion. However, testicular tissue structure was significantly better in the mannitol-treated group, demonstrating a protective effect. Similar findings were also shown for the proliferating cell nuclear antigen (PCNA) index and antioxidant activity; both were higher in the mannitol group than in the no-treatment and saline groups (p < 0.01). The apoptotic index was also significantly lower in the mannitol-treated group compared with the no treatment and saline groups (p < 0.01).

CONCLUSIONS

The seminiferous tubule structure in testicular torsion without mannitol treatment was significantly disturbed, whereas the structural disruption was considerably less in the mannitol group. Mannitol treatment also decreased reactive oxygen radical levels significantly and was able to decrease apoptosis. These results were consistent with other organ model studies that evaluated the protective effects of mannitol treatment in I/R injury. Mannitol infusion had a protective effect against I/R injury in testicular torsion in rats. This experimental study may guide clinicians to evaluate the effectiveness of mannitol in human testicular torsion.

ROS-Mediated NLRP3 Inflammasome Activation in Brain, Heart, Kidney, and Testis Ischemia/Reperfusion Injury

Ischemia and reperfusion (I/R) causes a reduction in arterial blood supply to tissues, followed by the restoration of perfusion and consequent reoxygenation. The reestablishment of blood flow triggers further damage to the ischemic tissue through reactive oxygen species (ROS) accumulation, interference with cellular ion homeostasis, and inflammatory responses to cell death. In normal conditions, ROS mediate important beneficial responses. When their production is prolonged or elevated, harmful events are observed with peculiar cellular changes. In particular, during I/R, ROS stimulate tissue inflammation and induce NLRP3 inflammasome activation. The mechanisms underlying the activation of NLRP3 are several and not completely elucidated. It was recently shown that NLRP3 might sense directly the presence of ROS produced by normal or malfunctioning mitochondria or indirectly by other activators of NLRP3. Aim of the present review is to describe the current knowledge on the role of NLRP3 in some organs (brain, heart, kidney, and testis) after I/R injury, with particular regard to the role played by ROS in its activation. Furthermore, as no specific therapy for the prevention or treatment of the high mortality and morbidity associated with I/R is available, the state of the art of the development of novel therapeutic approaches is illustrated.

The protective effect of lipoic acid on selected cardiovascular diseases caused by age-related oxidative stress

Oxidative stress is considered to be the primary cause of many cardiovascular diseases, including endothelial dysfunction in atherosclerosis and ischemic heart disease, hypertension, and heart failure. Oxidative stress increases during the aging process, resulting in either increased reactive oxygen species (ROS) production or decreased antioxidant defense. The increase in the incidence of cardiovascular disease is directly related to age. Aging is also associated with oxidative stress, which in turn leads to accelerated cellular senescence and organ dysfunction. Antioxidants may help lower the incidence of some pathologies of cardiovascular diseases and have antiaging properties. Lipoic acid (LA) is a natural antioxidant which is believed to have a beneficial effect on oxidative stress parameters in relation to diseases of the cardiovascular system.

The beneficial effect of melatonin in brain endothelial cells against oxygen-glucose deprivation followed by reperfusion-induced injury

Melatonin has a cellular protective effect in cerebrovascular and neurodegenerative diseases. Protection of brain endothelial cells against hypoxia and oxidative stress is important for treatment of central nervous system (CNS) diseases, since brain endothelial cells constitute the blood brain barrier (BBB). In the present study, we investigated the protective effect of melatonin against oxygen-glucose deprivation, followed by reperfusion- (OGD/R-) induced injury, in bEnd.3 cells. The effect of melatonin was examined by western blot analysis, cell viability assays, measurement of intracellular reactive oxygen species (ROS), and immunocytochemistry (ICC). Our results showed that treatment with melatonin prevents cell death and degradation of tight junction protein in the setting of OGD/R-induced injury. In response to OGD/R injury of bEnd.3 cells, melatonin activates Akt, which promotes cell survival, and attenuates phosphorylation of JNK, which triggers apoptosis. Thus, melatonin protects bEnd.3 cells against OGD/R-induced injury.

Mechanisms of testicular torsion and potential protective agents

Testicular torsion is a urological emergency most commonly seen in adolescence, involving a decrease in blood flow in the testis resulting from torsion of the spermatic cord that can result in gonad injury or even loss if not treated in time. Testicular ischaemia-reperfusion injury represents the principle pathophysiology of testicular torsion, with ischaemia caused by twisting of the spermatic cord, and reperfusion on its subsequent release. Many cellular and molecular mechanisms are involved in ischaemia-reperfusion injury following testicular torsion. Studies have investigated the use of pharmacological agents as supportive therapy to surgical repair in order to prevent the adverse effects of testicular torsion. Numerous substances have been proposed as important in the prevention of post-ischaemia-reperfusion testicular injury. A range of chemicals and drugs has been successfully tested in animal models for the purpose of mitigating the dangerous effects of ischaemia-reperfusion in testis torsion.

The short term effects of resveratrol on ischemia-reperfusion injury in rat testis

PURPOSE

The purpose of this study was to identify changes taking place in the rat testis at the 24th hour of reperfusion following testicular torsion and to evaluate the effects of resveratrol (RSV), a powerful antioxidant, in preventing these changes using novel biochemical parameters and histopathology.

METHODS

Eighteen adult male rats were divided into three groups: Sham-operated (S), torsion/detorsion (T/D), and T/D+RSV groups. In the T/D group, testicular ischemia was achieved by rotating the left testis 720° clockwise for 4h. In the T/D+RSV group, 20mg/kg RSV was administered intraperitoneally 30 min before detorsion. All rats were sacrificed 24h after detorsion. Serum and tissue malondialdehyde (MDA) concentrations, ischemia modified albumin (IMA), total oxidative status (TOS), total antioxidant status (TAS), oxidative stress index (OSI), and histopathological damage score were analyzed.

RESULTS

Serum MDA, IMA, TOS, and OSI levels rose significantly in the T/D group. Serum MDA and IMA values were lower in the T/D+RES groups, but not significantly. OSI and TOS values were lower in the T/D+RES group, and the difference was significant. TAS values decreased significantly in the T/D group and rose in the T/D+RSV group, but not significantly. Ipsilateral tissue MDA values were significantly elevated in the T/D group and decreased in the T/D+RSV group, but not significantly. Apoptosis and histopathological damage increased significantly in the T/D group and decreased significantly in the T/D+RSV group. In the contralateral testis, apoptosis increased significantly in the T/D group. It decreased significantly in the T/D+RSV group.

CONCLUSIONS

Our findings show that RSV had a protective effect against oxidative damage induced with a testicular T/D model, especially at the antiapoptotic and histopathological level. OSI may be a good guide to the clinical status of testicular T/D.

The effects of α-lipoic acid on liver oxidative stress and free fatty acid composition in methionine-choline deficient diet-induced NAFLD

Development of nonalcoholic fatty liver disease (NAFLD) occurs through initial steatosis and subsequent oxidative stress. The aim of this study was to examine the effects of α-lipoic acid (LA) on methionine-choline deficient (MCD) diet-induced NAFLD in mice. Male C57BL/6 mice (n=21) were divided into three groups (n=7 per group): (1) control fed with standard chow, (2) MCD2 group--fed with MCD diet for 2 weeks, and (3) MCD2+LA group--2 weeks on MCD receiving LA i.p. 100 mg/kg/day. After the treatment, liver samples were taken for pathohistology, oxidative stress parameters, antioxidative enzymes, and liver free fatty acid (FFA) composition. Mild microvesicular hepatic steatosis was found in MCD2 group, while it was reduced to single fat droplets evident in MCD2+LA group. Lipid peroxidation and nitrosative stress were increased by MCD diet, while LA administration induced a decrease in liver malondialdehyde and nitrates+nitrites level. Similary, LA improved liver antioxidative capacity by increasing total superoxide dismutase (tSOD), manganese SOD (MnSOD), and copper/zinc-SOD (Cu/ZnSOD) activity as well as glutathione (GSH) content. Liver FFA profile has shown a significant decrease in saturated acids, arachidonic, and docosahexaenoic acid (DHA), while LA treatment increased their proportions. It can be concluded that LA ameliorates lipid peroxidation and nitrosative stress in MCD diet-induced hepatic steatosis through an increase in SOD activity and GSH level. In addition, LA increases the proportion of palmitic, stearic, arachidonic, and DHA in the fatty liver. An increase in DHA may be a potential mechanism of anti-inflammatory and antioxidant effects of LA in MCD diet-induced NAFLD.

The effects of alpha-lipoic acid on MMP-2 and MMP-9 activities in a rat renal ischemia and re-perfusion model

Matrix metalloproteinases (MMPs) are enzymes that are responsible for degradation of extracellular matrix (ECM); they are involved in the pathogenesis of ischemia-re-perfusion (I-R) injury. We investigated the possible preventive effect of alpha-lipoic acid (LA) in a renal I-R injury model in rats by assessing its reducing effect on the expression and activation of MMP-2 and MMP-9 induced by I-R. Rats were assigned to four groups: control, sham-operated, I-R (saline, i.p.) and I-R+ LA (100 mg/kg, i.p.). After a right nephrectomy, I-R was induced by clamping the left renal pedicle for 1 h, followed by 6 h re-perfusion. In the sham group, a right nephrectomy was performed and left renal pedicles were dissected without clamping and the entire left kidney was excised after 6 h. LA pretreatment was started 30 min prior to induction of ischemia. Injury to tubules was evaluated using light and electron microscopy. The expressions of MMP-2 and MMP-9 were determined by immunohistochemistry and their activities were analyzed by gelatin zymography. Serum creatinine was measured using a quantitative kit based on the Jaffe colorimetric technique. Malondialdehyde (MDA) and glutathione (GSH) were analyzed using high performance liquid chromatography. Tissue inhibitor of metalloproteinase (TIMP)-2 and TIMP-1 were assessed using enzyme-linked immunosorbent assay (ELISA). I-R caused tubular dilatation and brush border loss. LA decreased both renal dysfunction and abnormal levels of MDA and GSH during I-R. Moreover, LA decreased significantly both MMP-2 and MMP-9 expressions and activations during I-R. TIMP-1 and TIMP-2 levels were increased significantly by LA administration. LA modulated increased MMP-2 and MMP-9 activities and decreased TIMP-1 and TIMP-2 levels during renal I-R.