Investigation of N-acetylcysteine on contralateral testis tissue injury by experimental testicular torsion: long-term effect

The Impact of Vitamin D and L-Cysteine Co-Supplementation on Upregulating Glutathione and Vitamin D-Metabolizing Genes and in the Treatment of Circulating 25-Hydroxy Vitamin D Deficiency

Vitamin D receptors are expressed in many organs and tissues, which suggests that vitamin D (VD) affects physiological functions beyond its role in maintaining bone health. Deficiency or inadequacy of 25(OH)VD is widespread globally. Population studies demonstrate that a positive association exists between a high incidence of VD deficiency and a high incidence of chronic diseases, including dementia, diabetes, and heart disease. However, many subjects have difficulty achieving the required circulating levels of 25(OH)VD even after high-dose VD supplementation, and randomized controlled clinical trials have reported limited therapeutic success post-VD supplementation. Thus, there is a discordance between the benefits of VD supplementation and the prevention of chronic diseases in those with VD deficiency. Why this dissociation exists is currently under debate and is of significant public interest. This review discusses the downregulation of VD-metabolizing genes needed to convert consumed VD into 25(OH)VD to enable its metabolic action exhibited by subjects with metabolic syndrome, obesity, and other chronic diseases. Research findings indicate a positive correlation between the levels of 25(OH)VD and glutathione (GSH) in both healthy and diabetic individuals. Cell culture and animal experiments reveal a novel mechanism through which the status of GSH can positively impact the expression of VD metabolism genes. This review highlights that for better success, VD deficiency needs to be corrected at multiple levels: (i) VD supplements and/or VD-rich foods need to be consumed to provide adequate VD, and (ii) the body needs to be able to upregulate VD-metabolizing genes to convert VD into 25(OH)VD and then to 1,25(OH)2VD to enhance its metabolic action. This review outlines the association between 25(OH)VD deficiency/inadequacy and decreased GSH levels, highlighting the positive impact of combined VD+LC supplementation on upregulating GSH, VD-metabolizing genes, and VDR. These effects have the potential to enhance 25(OH)VD levels and its therapeutic efficacy.

Effect of N-acetyl-L-cysteine on Testicular Tissue in Busulfan-Induced Dysfunction in the Male Reproductive System

PURPOSE

This study aimed to evaluate the protective effect of N-acetyl-L-cysteine (NAC) as an antioxidant on busulfan-induced testicular dysfunction in mice and elucidate its possible mechanism of action.

MATERIALS AND METHODS

Thirty-two C57BL/6 male mice were randomly divided into four groups (n=8/group) as follows: (1) control group (oral administration of saline [0.1 mL daily] for 35 days); (2) NAC group (oral administration of NAC [10 mg/kg daily] for 35 days); (3) busulfan group (double intraperitoneal injections of 20 mg/kg; total dose of 40 mg/kg); and (4) busulfan+NAC group (after double intraperitoneal injections of 20 mg/kg; total dose of 40 mg/kg, NAC administration [10 mg/kg daily] for 35 days). The testes were removed, weighed, and subjected to sperm parameter analysis and morphology assessment. Reproductive hormone, serum/testicular reactive oxygen species (ROS) level, oxidative stress and antioxidant markers were evaluated. The testicular expression of Nrf2 and HO-1 was examined using RT-qPCR.

RESULTS

Busulfan treatment significantly decreased testicular weight, sperm count, and serum testosterone levels. Atrophy and degeneration of germinal epithelium were observed in the busulfan group. NAC administration after busulfan treatment partially attenuated the deterioration of testis weight, sperm quality, serum hormones, histomorphometric changes, and oxidative and antioxidative status. NAC treatment resulted in a considerable improvement in Nrf2 and HO-1 mRNA expression levels.

CONCLUSIONS

This study provides compelling evidence that NAC as a potent antioxidant has significant protective effects against busulfan-induced male reproductive impairment possibly through modification of the Nrf2/HO-1 signaling pathway.

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.

Sinapic acid reduces ischemia/reperfusion injury due to testicular torsion/detorsion in rats

This study aimed to investigate the protective effect of sinapic acid (SA) on biochemical and histopathological changes in an experimental testicular torsion-detorsion rat model. Twenty-four rats were randomised into four groups: sham group, ischemia/reperfusion (IR) group subjected to testicular torsion for 2 hr and then detorsion for 4 hr, and two groups treated with SA1 and SA2 (10 mg/kg and 20 mg/kg, by single intraperitoneal injection, 30 min before reperfusion). Serum testosterone, follicle-stimulating hormone (FSH), and luteinizing hormone (LH) were measured by an autoanalyzer, superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), malondialdehyde (MDA), protein carbonyl (PC), and nitric oxide (NO) oxidative stress parameters by spectrophotometric methods, and tumour necrosis factor (TNF-α), interleukin-1 beta (IL-1β), and interleukin 6 (IL-6) parameters by the Elisa method. In addition, immunohistochemical and histopathological examinations were performed on testicular tissues. There was no significant difference between the groups in terms of serum testosterone, FSH and LH levels (p > .05). SA significantly reduced increased testicular damage, oxidative stress, inflammation, cell death and also restored decreased antioxidant enzyme activities (p < .05). Pre-treatment of rats with SA reduced testicular dysfunction and morphological changes IRI. SA's antioxidant, anti-inflammatory, and antiapoptotic properties were found to be protective against testicular IR.

Antioxidant effects of N-acetylcysteine on the male reproductive system: A systematic review

This study aimed to evaluate the effect of N-acetyl cysteine on the male reproductive system and consensus and classification of data found from previous studies. It is undeniable that N-acetyl cysteine as a powerful antioxidant compound can medicate many diseases such as cardiovascular, kidney, liver and reproductive system disorders. With the increasing environmental pollution that has a direct adverse effect on male fertility, the use of this compound is able to positively function on human fertility health. In this study, we have been collected the main data of scientific articles (1994-2020) about N-acetyl cysteine effects. By searching in the scientific databases of PubMed, Google Scholar, Science Direct, Wiley and Web of Science, related articles were extracted. As a result, all observations have confirmed that N-acetyl cysteine can improve and normalise the spermatogenesis in the male reproduction system.

Prevention of the harmful effects of free oxygen radicals by using N-acetylcysteine in testicular torsion

INTRODUCTION

Testicular torsion is a urological emergency both in childhood and in adult life. Many studies on experimental testicular torsion have demonstrated biochemical and pathological ischemia-reperfusion injury and the efficacy of some drugs have been investigated to prevent this damage. N-acetylcysteine (NAC) promotes glutathione synthesis and acts as a glutathione precursor because of the fact that it increases the glutathione-reductase activity by transporting sulfhydryl groups.

AIM

In this experimental study, the authors aimed to investigate the effectiveness of NAC in preventing ischemia-reperfusion injury following testicular torsion and detorsion.

STUDY DESIGN

For this experimental study, 36 albino Wistar-male rats were used. The rats were randomly divided into 4 groups: sham (n = 8), ischemia-reperfusion (n = 8), ischemia-NAC -reperfusion (n = 10), and ischemia-NAC-reperfusion-NAC (n = 10) groups. Two hours of torsion and 4 h of detorsion were created in the left testis. After 4 h of detorsion, the rats were sacrificed. Each tissue was divided into two sections for biochemical and pathological examinations.

RESULTS

There was a statistically significant difference between the study groups in terms of the total-sulfhydryl level, nitric oxide level, and the malondialdehyde values. Histopathological examination revealed that NAC was effective in preventing reperfusion injury in the testis but ineffective in preventing the reduction in the spermatid count.

DISCUSSION

The results of this experimental study support that NAC can histopathologically maintain the structure of seminiferous tubules against ischemis reperfusion injury and prevent damage to the germinative cells. However, it was unable to prevent the reduction in spermatid count. There was no significant difference in the prevention of ischemia-reperfusion injury between NAC administration during the first hour of ischemia and NAC administration during reperfusion. Although NAC can prevent tissue damage from ischemia reperfusion injury, it is not effective against the reduction in the spermatid count.

CONCLUSION

N-acetylcysteine may be biochemically effective in preventing ischemia-reperfusion injury after testicular torsion and detorsion. NAC is a readily available and easy to use agent that can be used during testicular ischemia.

N-acetylcysteine protects testicular tissue against ischemia/reperfusion injury via inhibiting endoplasmic reticulum stress and apoptosis

BACKGROUND

In animal models, endoplasmic reticulum (ER) stress has been reported to play a vital role in mediating ischemia/reperfusion (I/R) injury in certain organs, such as brain, liver, and intestine. However, there are a limited number of studies examining the relationship between ER stress and torsion and detorsion (T/D)-induced testicular injury.

OBJECTIVE

To investigate the effects of N-acetylcysteine (NAC) on ER-stress and apoptosis in an experimental testicular I/R injury model.

DESIGN

A non-blinded experimental study with three arms. Rats were divided into three groups: control group, T/D group, and NAC group. In the pretreatment of the NAC group, 20 mg/kg NAC was given intraperitoneally 30 min before detorsion. Tissue 4-hydroxynonenal (4-HNE), 78-kDa glucose-regulated protein (GRP78), and activating transcription factor 6 (ATF6) levels were determined using enzyme-linked immunosorbent assay. The apoptosis levels were evaluated using terminal deoxynucleotide transferase-mediated dUTP nick-end label assay.

RESULTS

In T/D group, tissue 4-HNE, GRP78, ATF6, and apoptotic index levels were significantly higher than control group. These increases were significantly reversed with NAC pretreatment.

DISCUSSION

There are some potential drugs that have been shown to reduce ER stress in the experimental ischemia model, and it is questioned that these drug candidates can be used as a therapeutic agent in the treatment of ischemic diseases in the near future. This study was not without limitations. First, the authors applied NAC only 20 mg/kg. In a future study, a dose-dependent assay should be performed to assess the likelihood of an additional testicular protective effect. One limitation of this research is also that in vivo studies cannot be extrapolated to possible effect in clinics. More experiments therefore need to be conducted to extrapolate the study findings to humans.

CONCLUSION

The study results showed that, after testicular torsion (TT), the ER stress-related apoptotic pathway plays a pivotal role in testicular injury. Further studies of other experimental models of TT may prove that NAC is a useful agent as an adjunctive treatment in surgical repair in human cases.

Effects of platelet-rich plasma against experimental ischemia/reperfusion injury in rat testis

BACKGROUND

Testicular torsion is a common problem and, to date, there is no agent to preserve testicular function following detorsion. Platelet-rich plasma (PRP), with its rich growth factor composition, has proven beneficial in regenerative therapy. It is believed that PRP has not been studied in testis for ischemia/reperfusion (I/R) injury.

OBJECTIVE

This study investigated the effect of PRP in an I/R rat model 1 month after detorsion.

STUDY DESIGN

Of 24 adult male Sprague-Dawley rats, 18 were randomly assigned into three groups, with six in each: control, I/R and I/R + PRP. The PRP was prepared from the remaining six. Each group underwent right orchiectomy. Ischemia was performed by rotating the left testis 720° and fixing with a nylon suture for 4 h. Reperfusion occurred 4 h later by removing the suture, and PRP was administered at a dose of 10 μl (2000 × 10⁹/l) into the left testis via the intraparenchymal route. Animals were sacrificed at the fourth week, and testes were taken for malondialdehyde (MDA), glutathione (GSH), superoxide dismutase (SOD), myeloperoxidase (MPO), transforming growth factor β (TGF-β), and caspase-3 measurements.

RESULTS

Ischemia/reperfusion caused a significant increase in MDA, MPO and caspase-3 activity, and significant decrease in GSH levels and SOD activity. The PRP treatment helped correct the alterations in SOD, caspase-3, and MPO activities and MDA levels. However, the mean MDA level and MPO activity were not totally restored compared with the controls. Serum testosterone levels of the I/R group were significantly lower compared with the control and I/R + PRP groups. TGF-β and caspase-3 protein expressions were significantly higher in the I/R group compared with the control group and were low with PRP administration compared with I/R groups (summary Table).

DISCUSSION

The findings of the present study suggest that PRP, by inhibiting neutrophil infiltration and oxidative stress and increasing antioxidant defense, exerts protective effects on testicular tissues against I/R. This study had some limitations: a scoring system was not used in the assessment of spermatogenesis in the histopathological findings and specific testis cell types were not histologically assessed.

CONCLUSIONS

In light of the biochemical, histological and, especially, hormonal findings, intraparenchymal PRP injection may have a protective effect in testicular tissue against I/R injury.