Mechanism mediating the protective effect of diacerein in ischemia-reperfusion-induced testicular injury in rats

Diacerein and myo-inositol alleviate letrozole-induced PCOS via modulation of HMGB1, SIRT1, and NF-kB: A comparative study

Polycystic ovary syndrome (PCOS) is the most prevalent cause of anovulatory infertility in women. Myo-inositol supplementation has displayed effectiveness in curing PCOS patients. Diacerein, an anti-inflammatory medication, has not been extensively studied in the context of reproductive disorders. This study aimed to compare the role of myo-inositol and diacerein in PCOS and the probable mechanisms mediating their actions. Forty adult female rats were divided equally into the following: control, PCOS, PCOS+Myo-inositol, and PCOS+Diacerein groups. Rats were subjected to arterial blood pressure (ABP), electromyography (EMG), and uterine reactivity measurements. Blood samples were collected for measuring hormonal assays, glycemic state, lipid profile, oxidative stress, and inflammatory markers. Ovaries and uteri were extracted for histological examination, including hematoxylin and eosin staining, Masson's trichrome staining, immunohistochemistry, and rt-PCR analysis of ovarian tissues. PCOS was associated with significant increases in ABP, uterine frequency and amplitude of contraction, luteinizing hormone, testosterone, lipid, glycemic and inflammatory markers, malondialdehyde, high-mobility group box 1 (HMGB1), nuclear factor kappa (NF-kB), ovarian fibrosis, and endometrial thickening. In contrast, there was a significant reduction in follicular stimulating hormone, reduced glutathione, and Sirtuin 1 (SIRT1) when compared with control group. Both myo-inositol and diacerein counteract PCOS changes; but diacerein's effects were superior to myo-inositol's for all parameters, except for lipid and glycemic markers. Diacerein possessed anti-inflammatory properties and showed significant efficacy in mitigating the endocrinal, metabolic, and ovarian structural alterations linked to PCOS. Its beneficial actions likely stem from reducing oxidative stress, dyslipidemia, and hyperglycemia, potentially through the modulation of HMGB1, SIRT1, and NF-kB pathways.

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

BACKGROUNDS & AIM

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

MATERIAL & METHODS

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

KEY FINDINGS

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

CONCLUSION

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

Reduction of osteoclast formation and survival following suppression of cytokines by diacerein in periodontitis

Periodontitis causes an increase in several bioactive agents such as interleukins (IL), tumor necrosis factor (TNF)-α and receptor activator of NF-kB ligand (RANKL), which induce the osteoclast formation and activity. Since diacerein exerts anti-TNF-α and anti-IL-1 effects, alleviating bone destruction in osteoarthritis, we investigated whether this drug inhibits the formation and survival of osteoclast in the periodontitis. Rats were distributed into 3 groups: 1) group with periodontitis treated with 100 mg/kg diacerein (PDG), 2) group with periodontitis treated with saline (PSG) and group control (CG) without any treatment. After 7, 15 and 30 days, the maxillae were collected for light and transmission electron microscopy analyses. Gingiva samples were collected to evaluate the mRNA levels for Tnf, Il1b, Tnfsf11 and Tnfrsf11b by RT-qPCR. In PDG, the expression of Tnf and Il1b genes reduced significantly compared to PSG, except for Tnf expression at 7 days. The number of osteoclasts reduced significantly in the PDG in comparison with PSG at 7 and 15 days. In all periods, the IL-6 immunoexpression, RANKL/OPG immunoexpression and mRNA levels of Tnfsf11/Tnfrsf11b ratio were significantly lower in PDG than in PSG. PDG exhibited significantly higher frequency of TUNEL-positive osteoclasts than in PSG and CG at all time points. Osteoclasts with caspase-3-immunolabelled cytoplasm and nuclei with masses of condensed chromatin were observed in PDG, confirming osteoclast apoptosis. Diacerein inhibits osteoclastogenesis by decreasing Tnf and Il1b mRNA levels, resulting in decreased RANKL/OPG ratio, and induces apoptosis in osteoclasts of alveolar process of rat molars with periodontitis.

Diacerein mitigates endocrine and cardio-metabolic disruptions in experimental PCOS mice model by modulating AdipoR1/ PON 1

BACKGROUND

This study aimed to explore the impact of Diacerein (DIC) on endocrine and cardio-metabolic changes in polycystic ovarian syndrome (PCOS) mouse model.

METHODS

A total of 18 adult female mice (Parkes strain), aged 4-5 weeks, were randomly assigned to three groups, each comprising 6 animals, as follows: Group I (control), received normal diet and normal saline as vehicle for 51 days; Group II received Letrozole (LET; 6 mg/kg bw) for 21 days to induce PCOS; Group III received LET, followed by daily oral gavage administration of DIC (35 mg/kg bw) for 30 days.

RESULTS

This study indicates that treatment with LET resulted in PCOS with characteristics such as polycystic ovaries, elevated testosterone, weight gain, visceral adiposity, high levels of insulin as well as fasting blood glucose in addition to insulin resistance, improper handling of ovarian lipids, atherogenic dyslipidemia, impaired Na + /K + -ATPase activity and serum, cardiac, and ovarian oxidative stress. Serum/ovarian adiponectin levels were lowered in LET-treated mice. In mice treated with LET, we also discovered a reduction in cardiac and serum paraoxonase 1 (PON1). Interestingly, DIC restored ovarian andcardio-metabolic abnormalities in LET-induced PCOS mice. DIC prevented the endocrine and cardio-metabolic changes brought on by letrozole-induced PCOS in mice.

CONCLUSION

The ameliorative effects of DIC on letrozole-induced PCOS with concurrent oxidative stress, abdominal fat deposition, cardiac and ovarian substrate mishandling, glucometabolic dysfunction, and adiponectin/PON1 activation support the idea that DIC perhaps, restore compromised endocrine and cardio-metabolic regulators in PCOS.

Sodium acetate prevents testicular damage in Wistar rats subjected to testicular ischaemia/reperfusion injury

AIMS

The aim of this study was to investigate the potential antioxidant, anti-inflammatory, and sperm function-preserving properties of sodium acetate (ACE), a histone deacetylase (HDAC) inhibitor, in a rat model of testicular torsion/detorsion (T/D).

MAIN METHODS

Littermate Wistar rats of identical weight were subjected to sham surgery or testicular T/D by rotating the left testis at 720° around its axis along the spermatic cord clockwise and fixing it in this position for two and a half hours. 1 h before detorsion, T/D + ACE-treated rats were treated with ACE (200 mg/kg/day, per os) while T/D rats were vehicle-treated by administering 0.5 mL of distilled water. After 72 h, animals were euthanized, and the left testes were harvested for bio-molecular and histological analysis.

KEY FINDINGS

Acetate administration attenuated T/D-induced rises in serum and testicular HDAC and testicular xanthine oxidase, uric acid, MDA, GSSG, MPO, TNF-α, IL-1β, IL-6, NFkB, HIF-1α, and VCAM-1. In addition, acetate treatment alleviated T/D-induced decline in sperm quality (count, motility, viability, and normal morphology) and testicular 3β-HSD, 17β-HSD, testosterone, GSH, GSH/GSSG, SOD, catalase, GPx, GST, Nrf2, and HO-1. Furthermore, acetate prevented T/D-distorted testicular histoarchitecture and spermatogenic germ cell loss.

SIGNIFICANCE

Sodium acetate during the post-ischaemic phase of testicular T/D may be beneficial in preventing I/R injury and maintaining fertility.

Role of Nrf2/HO-1, PPAR-γ, and cytoglobin signals in the pathogenesis of methotrexate-induced testicular intoxication in rats and the protective effect of diacerein

Methotrexate (MTX) is an inhibitor of folic acid reductase used in managing a variety of malignancies. Testicular injury by MTX is one of its serious adverse effects. The current investigation aims to assess the protective effects of diacerein (DIA) on testicular injury by MTX and clarify the possible underlying mechanisms. Testicular injury in rats was induced by a single injection of 20 mg/kg body weight of MTX. DIA was given in 25 mg/kg body weight/day and 50 mg/kg body weight/day doses for 10 days. Compared to the MTX group, DIA attenuated testicular intoxication as evidenced by improvement of testicular histopathological abnormalities and increased serum testosterone and luteinizing hormone. DIA attenuated testicular oxidative stress changes by lowering testicular MDA and boosting GSH content and SOD activity. Moreover, administration of DIA attenuated MTX-induced testicular inflammation, as proved by decreased TNF-α and IL-6. At the molecular level, DIA induced significant upregulation in Nrf2, HO-1, PPAR-γ, and cytoglobin protein expression. The present results proved that DIA, in a dose-dependent manner, exhibited notable amelioration of testicular toxicity induced by MTX through augmentation of anti-inflammatory and antioxidant effects combined by upregulating Nrf2/HO-1, PPAR-γ, and cytoglobin signaling.

Pathophysiology and management of testicular ischemia/reperfusion injury: Lessons from animal models

Testicular torsion is a urological emergency that involves the twisting of the spermatic cord along its course. Compelling pieces of evidence have implicated oxidative stress-sensitive signaling in pathogenesis of testicular I/R injury. Although, surgical detorsion is the mainstay management; blockade of the pathways involved in the pathogenesis may improve the surgical outcome. Experimental studies using various testicular I/R models have been reported in a bid to explore the mechanisms associated with testicular I/R and evaluate the benefits of potential therapeutic measures; however, most are limited by their shortcomings. Thus, this review was intended to describe the details of the available testicular I/R models as well as their merits and drawbacks, the pathophysiological basis and consequences of testicular I/R, and the pharmacological agents that have being proposed to confer testicular benefits against testicular I/R. This provides an understanding of the pathophysiological events and available models used in studying testicular I/R. In addition, this research provides evidence-based molecules with therapeutic potentials as well as their mechanisms of action in testicular I/R.

Inhibition of NLRP3 inflammasome-A potential mechanistic therapeutic for treatment of polycystic ovary syndrome?

This review article explores the relationship between the NOD-like receptor protein 3 (NLRP3) inflammasome and the risk of developing polycystic ovary syndrome (PCOS). The NLRP3 inflammasome, a fundamental element of the innate immune system, plays a crucial role in the production of proinflammatory mediators and pyroptosis, a type inflammatory cell death. We conducted a thorough search on scientific databases to gather relevant information on this topic, utilizing relevant keywords. The reviewed studies indicated a correlation between PCOS and a higher incidence of granulosa cell (GC) death and the presence of ovarian tissue fibrosis. NLRP3 inflammasome stimulation and subsequent pyroptosis in GCs play a significant role in the pathophysiology of PCOS. Active NLRP3 inflammasome is involved in the production of inflammatory mediators like interleukin-1β (IL-1β) and IL-18, contributing to the development of PCOS, particularly in overweight patients. Therefore, inhibiting NLRP3 activation and pyroptosis could potentially offer novel therapeutic strategies for PCOS. Some limited studies have explored the use of agents with antioxidant and anti-inflammatory properties, as well as gene therapy approaches, to target the NLRP3 and pyroptosis signaling pathways. This study overview the understanding of the relationship between NLRP3 inflammasome activation, pyroptosis, and PCOS. It highlights the potential of targeting the NLRP3 inflammasome as an approach for treating PCOS. Nonetheless, further research and clinical trials are imperative to validate these results and explore the effectiveness of NLRP3 inflammasome inhibition in the management of PCOS.

Diacerein provokes apoptosis, improves redox balance, and downregulates PCNA and TNF-α in a rat model of testosterone-induced benign prostatic hyperplasia: A new non-invasive approach

One of the most prevalent chronic conditions affecting older men is benign prostatic hyperplasia (BPH), causing severe annoyance and embarrassment to patients. The pathogenesis of BPH has been connected to epithelial proliferation, inflammation, deranged redox balance, and apoptosis. Diacerein (DIA), the anthraquinone derivative, is a non-steroidal anti-inflammatory drug. This study intended to investigate the ameliorative effect of DIA on the prostatic histology in testosterone-induced BPH in rats. BPH was experimentally induced by daily subcutaneous injection of testosterone propionate for four weeks. The treated group received DIA daily for a further two weeks after induction of BPH. Rats' body and prostate weights, serum-free testosterone, dihydrotestosterone, and PSA were evaluated. Prostatic tissue was processed for measuring redox balance and histopathological examination. The BPH group had increased body and prostate weights, serum testosterone, dihydrotestosterone, PSA, and oxidative stress. Histologically, there were marked acinar epithelial and stromal hyperplasia, inflammatory infiltrates, and increased collagen deposition. An immunohistochemical study showed an increase in the inflammatory TNF-α and the proliferative PCNA markers. Treatment with DIA markedly decreased the prostate weight and plasma hormones, improved tissue redox balance, repaired the histological changes, and increased the proapoptotic caspase 3 expression besides the substantial reduction in TNF-α and PCNA expression. In conclusion, our study underscored DIA's potential to alleviate the prostatic hyperplastic and inflammatory changes in BPH through its antioxidant, anti-inflammatory, antiproliferative, and apoptosis-inducing effects, rendering it an effective, innovative treatment for BPH.

Testicular torsion in vivo models: Mechanisms and treatments

BACKGROUND

Testicular torsion is a condition in which a testis rotates around its longitudinal axis and twists the spermatic cord. This in turn results in a significant decrease in blood flow and perfusion of testicular tissue. During Testicular torsion, the testicular tissue is affected by ischemia, heat stress, hypoxia, and oxidative and nitrosative stress. The testicular torsion should be considered an emergency condition and surgical intervention (testicular detorsion ) as the sole treatment option in viable cases involves counter-rotation on twisted testes associated, when possible, to orchipexy, in order to avoid recurrence. Possible testicular detorsion side-effects occur due to reperfusion and endothelial cells injury, microcirculation disturbances, and intense germ cells loss.

OBJECTIVES

To discuss testicular torsion surgery-based methods, different time frames for testicular torsion induction, and the associated pathophysiology by emphasizing cellular and molecular events as well as different therapeutic agent applications for testicular torsion.

MATERIALS AND METHODS

We reviewed all original research and epidemiological papers related to testicular torsion condition.

RESULTS

Testicular torsion causes germ cell necrosis, arrested spermatogenesis, and diminished testosterone levels, with consequent infertility. Among different involved pathophysiological impacts, testicular torsion/detorsion-induced ischemia seems to play the key role by leading the tissue toward other series of events in testis. Numerous studies have used adjuvant antioxidants, calcium channel blockers, anti-inflammatory agents, or vasodilating agents in order to decrease these effects.

DISCUSSION AND CONCLUSION

To the best of our knowledge, no previously conducted study examined therapeutical agents' beneficial effects post clinical I/R condition in humans. Different agents targeting different pathophysiological conditions were used to ameliorate the ischemia/reperfusion-induced condition in animal models, however, none of the administrated agents were tested in human cases. Although considering testicular detorsion surgery is still the golden method to reverse the testicular torsion condition and the surgical approach is undeniable, the evaluated agents with beneficial effects, need to be investigated furthermore in clinical conditions. Thus, furthermore clinical studies and case reports are required to approve the animal models proposed agents' beneficial impacts.

Diacerein modulates TLR4/ NF-κB/IL-1β and TRPC1/CHOP signalling pathways in gentamicin-induced parotid toxicity in rats

The present study aimed to identify the possible protective effect of diacerein (DIA) on gentamicin (GNT)-induced parotid toxicity in rats. DIA was administered in the presence and absence of GNT. Thirty-two Wistar adult male rats were randomly arranged into four groups: control, DIA (50 mg/kg/day), GNT (100 mg/kg) and GNT+DIA groups for 8 days. Parotid oxidative stress parameters, besides inflammatory and apoptotic biomarkers, were evaluated. Salivary flow rate, transient receptor potential canonical 1 (TRCP1), and C/EBP homologous protein (CHOP) in parotid tissue were measured. A parotid histopathological examination and an interleukin-1 beta (IL-1β) immunohistochemical study were also performed. GNT significantly increased parotid oxidative stress, inflammatory, apoptotic and CHOP biomarkers with decreased salivary flow rate and TRCP1 level. A histopathological picture of parotid damage and high IL-1β immunoexpression were detected. DIA significantly normalized the distributed oxidative, inflammatory and apoptotic indicators, CHOP and TRCP1, with a prompt improvement in the histopathological picture and a decrease in IL-1β immunoexpression. These results reported that DIA protects against GNT-induced parotid toxicity via modulation of TLR4/NF-κB/IL-1β and TRPC1/CHOP signalling pathways.

Role of diacerein on steroidogenesis and folliculogenesis related genes in ovary of letrozole-induced PCOS mice

Polycystic ovary syndrome (PCOS), an intricate and multifaceted metabolic-endocrine disorder that typically affects 6-20% of women of reproductive age and accounts for 70-80% of all occurrences of infertility globally. In this study we focussed on the effect of diacerein (DIC) on steroidogenesis and follicle development in addition to the basic metabolic and endocrine problems which are associated with PCOS. Eighteen mature female parkes strain mice were separated into three groups at random with 6 animals in a group as follows: Group I, received water and normal diet for 66 days; group II received letrozole (LETZ) (6 mg/kg bw) for the induction of PCOS; Group III received LETZ (6 mg/kg) for 3 weeks followed by the administration of DIC (35mg/kg) for 45 days. In our study we observed that mice with PCOS had irregular estrous cycle with increased LH/FSH, estrogen level and decline in expression of Kitl, Bmp, Cyp11a1, CYP19a1, Ar, lhr, Fshr and Esr1 as well as decreased SOD and CAT activity in ovary. Moreover, we observed increase in the expression of CYP17a1, as well as increase in serum cholesterol, triglycerides, testosterone, LH, VEGF and insulin levels. All these changes were reversed after the administration of DIC in PCOS mice. Diacerin administration reversed abnormalities in mice with PCOS by modulating the regulation of genes which are related to steroidogenesis and folliculogenesis.

TLR4/ MyD88/NF-κB signaling pathway involved in the protective effect of diacerein against lung fibrosis in rats

PURPOSE

Pulmonary fibrosis (PF) is an inescapable problem. Diacerein, a chondro-protective drug, has antioxidant and anti-inflammatory effects. Its effect on PF injury has not yet been fully clarified. Therefore, the current study aimed to detect its protective effect on lung tissue with the explanation of possible underlying mechanisms.

METHODS

Adult male albino rats were assigned to four groups: control group, diacerein control group, PF non-treated group, and PF diacerein pretreated group. Lung tissue oxidative stress parameters, inflammatory biomarkers mainly Toll-like receptors-4 (TLR4), and myeloid differentiation factor 88 (MyD88) levels were determined. Histopathological examination of lung tissue and immunohistochemical studies of nuclear factor-kappa B (NF-κB), and transforming growth factor- β (TGF-β) were also done.

RESULTS

Diacerein pretreatment has the ability to restore the PF damaging effect, proved by the reduction of the oxidative stress and lung tissue inflammation via downregulation of TLR4/NF-κB signaling pathway together with the restoration of TGF-β level and improvement of the histopathological and immunohistochemical study findings in the lung tissue.

CONCLUSION

These results suggested the protective effect of diacerein on PF relies on its antioxidant and anti-inflammatory effects reducing TLR4/NF-κB signaling pathway.

Diacerein alleviates Ang II-induced cardiac inflammation and remodeling by inhibiting the MAPKs/c-Myc pathway

BACKGROUND

Heart failure is a common event in the course of hypertension. Recent studies have highlighted the key role of the non-hemodynamic activity of angiotensin II (Ang II) in hypertension-related cardiac inflammation and remodeling. A naturally occurring compound, diacerein, exhibits anti-inflammatory activities in various systems.

HYPOTHESIS/PURPOSE

In this study, we have examined the potential effects of diacerein on Ang II-induced heart failure.

METHODS

C57BL/6 mice were administered Ang II by micro-osmotic pump infusion for 4 weeks to develop hypertensive heart failure. Mice were treated with diacerein by gavage for final 2 weeks. RNA-sequencing analysis was performed to explore the potential mechanism of diacerein.

RESULTS

We found that diacerein could inhibit inflammation, myocardial fibrosis, and hypertrophy to prevent heart dysfunction, without the alteration of blood pressure. To explore the potential mechanism of diacerein, RNA-sequencing analysis was performed, indicating that MAPKs/c-Myc pathway is involved in that cardioprotective effects of Diacerein. We further confirmed that diacerein inhibits Ang II-activated MAPKs/c-Myc pathway to reduce inflammatory response in mouse hearts and cultured cardiomyocytes. Deficiency of MAPKs or c-Myc in cardiomyocytes abolished the anti-inflammatory effects of diacerein.

CONCLUSION

Our results indicate that diacerein protects hearts in Ang II-induced mice through inhibiting MAPKs/c-Myc-mediated inflammatory responses, rendering diacerein a potential therapeutic candidate agent for hypertensive heart failure.

Diacerein ameliorates acetaminophen hepatotoxicity in rats via inhibiting HMGB1/TLR4/NF-κB and upregulating PPAR-γ signal

BACKGROUND

Acetaminophen (APAP) is a worldwide antipyretic as well as an analgesic medication. It has been extensively utilized during the outbreak of coronavirus 2019 (COVID-19). APAP misuse would lead to liver injury. Diacerein (DIA), an anthraquinone derivative, has antioxidant and inflammatory properties. Hence, this study attempted to evaluate the impact of DIA treatment on liver injury induced by APAP and its influence on nuclear factor-κB (NF-κB) /toll-like receptor 4 (TLR4)/high mobility group box-1(HMGB-1) signaling as well as the expression of peroxisome proliferator-activated receptor-gamma (PPAR-γ) expression.

METHODS

Male albino rats received 25 as well as 50 mg/kg/day DIA orally for seven days. One hour after the last administration, rats received APAP (1gm/kg, orally). For histopathological analysis, liver tissues and blood were collected, immunohistochemical (IHC) assay, biochemical assay, as well as quantitative real-time polymerase chain reaction (qRT-PCR).

RESULTS

DIA markedly reduced liver injury markers and ameliorated histopathological changes. Moreover, DIA dose-dependently alleviated oxidative stress status caused by APAP administration along with inflammatory markers, including the level of interleukin-1 beta (IL-1β), myeloperoxidase (MPO), tumor necrosis factor-alpha (TNF-α), and interleukin 6 (IL-6). Furthermore, DIA downregulated protein levels as well as mRNA of HMGB-1, TLR4, NF-κB p65 expression, and enhanced PPAR-γ expression. Moreover, DIA ameliorated apoptotic (Bax) and caspase-3 expressions and increased the anti-apoptotic (Bcl2) expression.

CONCLUSIONS

This study demonstrated that DIA exerts anti-apoptotic, anti-inflammatory, and antioxidant properties against liver injury induced by APAP that is attributed to inhibition of the HMGB1/TLR4/NF-κB pathway, besides upregulation of the expression of PPAR-γ.

The NLRP3 inflammasome: molecular activation and regulation in spermatogenesis and male infertility; a systematic review

Background

Infertility related to varicocele, infections, metabolic dysfunctions, oxidative stress and environmental toxicants is also associated with inflammatory processes that ultimately lead to the activation of the inflammasome pathway (IP). IP is classically activated by DAMPs, MAMPs or LAMPs, which stand for Damage-, Microbe- or Lifestyle-Associated Molecular Patterns, respectively. The most important player in IP activation is the NLRP3 (NOD[Nuclear oligomerization domain]-, LRR[Leucine rich repeat]- and pyrin domain-containing protein 3) which functions as an intracellular sensor of D/M/L-AMPs resulting in activation of caspase-1, promotion of apoptosis, pyroptosis and generation of inflammatory cytokines. This review addresses the question of whether IP activation might be associated with male infertility situations.

Results & conclusions

We conducted a systematic review of articles published in the Google Scholar, and PubMed databases through October 2021. It turns out that inflammasome activation and its consequences including cytokine storms, apoptosis and pyroptosis could be associated with the reduced sperm count as well as the structural and functional sperm defects recorded in several situations associated with male infertility suggesting that anti-inflammatory therapeutic strategies could be possibly considered to restore male fertility in future research.

Diacerein ameliorates letrozole-induced polycystic ovarian syndrome in rats

Polycystic ovary syndrome (PCOS) is the most common gynaecological endocrine disease that causes anovulatory infertility. The current study aimed to explore the possible role of diacerein (DIA), an IL-1β inhibitor, in treating letrozole-induced PCOS in rats that exhibit the metabolic and endocrinal criteria of PCOS patients. PCOS was induced in female Wistar rats by the oral administration of letrozole (1 mg/kg, per orally, p.o.) for 21 days. Rats were then treated with DIA (25 mg/kg/day, p.o.), DIA (50 mg/kg/day, p.o.), or metformin (2 mg/100 g/day, p.o.) for 14 days after the PCOS induction. PCOS resulted in a significantly higher body weight, ovarian weight, ovarian size, and cysts, as well as an elevation in serum testosterone, LH, insulin, glycemia, and lipid profile levels. All of these effects were significantly reduced by the DIA administration. Additionally, DIA remarkably inhibited the letrozole-induced oxidative stress in the ovaries, muscles, and liver by reducing the upraised levels of malondialdehyde and total nitrite and increasing the suppressed levels of superoxide dismutase and catalase. DIA enhanced the protective proteins Keap-1, Nrf2, and OH-1 levels. Finally, DIA inhibited the elevated mRNA levels of NLRP3 and caspase-1, the up-regulated inflammatory cytokines IL-6, TNF-α, and the IL-1β/NFκB signaling pathway. Our results proved that DIA ameliorates letrozole-induced PCOS through its antioxidant and anti-inflammatory properties.

Idebenone regulates sirt1/Nrf2/TNF-α pathway with inhibition of oxidative stress, inflammation, and apoptosis in testicular torsion/detorsion in juvenile rats

Testicular torsion is an emergency, mainly in newborn and adolescent males, resulting in testicular ischemia. The current study aimed to evaluate the effect of Idebenone (IDE) on testicular torsion/detorsion (T/D) in juvenile rats. Thirty-two rats were randomized into: (1) the sham group: rats received sham operations with no other interventions; (2) the IDE group: rats received idebenone (100 mg/kg, i. p) without T/D; (3) the T/D group: rats underwent torsion for 2 h and detorsion for 4 h; and (4) the IDE+ T/D group: rats received IDE 1 h before T/D. Testicular malondialdehyde (MDA), total nitrite/nitrate (NOx), total antioxidant capacity (TAC), tumor necrosis factor-α (TNF-α), caspase-3, sirtuin type 1 (Sirt1), serum interleukin-1β (IL-1β), total cholesterol, and testosterone were measured. Histological changes, nuclear factor (erythroid-derived 2)-like-2 factors (Nrf2), and proliferating cell nuclear antigen (PCNA) immuno-expressions were assessed. T/D displayed an increase in MDA, NOx, TNF-α, caspase-3, IL-1β, and total cholesterol with a significant decrease in TAC, Sirt1, and testosterone and strong positive Nrf2 and negative PCNA immuno-expressions. IDE could improve all oxidative, inflammatory, and apoptotic indicators. Therefore, IDE significantly reduced testicular ischemia-reperfusion injury in the juvenile rat testicular T/D model by limiting oxidative stress, inflammation, and apoptosis via the Sirt1/Nrf2/TNF-α pathway.

Molecular mechanisms underlying the effect of diacerein on trichloroacetic acid-induced hepatic pre-neoplastic lesions in rats

CONCLUSION

IL-1β mediates angiogenesis indirectly, as it has been shown to induce hypoxia-inducible factor-1α (HIF-1α) which upregulates VEGF.

Dose dependent effect of cilostazol in induced testicular ischemia reperfusion via modulation of HIF/VEGF and cAMP/SIRT1 pathways

Twisting of the spermatic cord is a common dangerous health problem that may be accompanied with testicular necrosis and infertility. Cilostazol (CLZ) is a selective phosphodiesterase (PDE) 3A inhibitor used for treatment of intermittent claudication. It has a great role in myocardial, spinal cord and hepatic ischaemia/reperfusion. However, till now, there are no researches evaluating its role in testicular ischaemia/reperfusion (TIR). The current work studies its capability to improve TIR induced injury with more concentration on the mechanisms involved in such effect. Four groups of animals were included: sham, TIR induced group, TIR plus CLZ low dose (10 mg/kg), TIR plus CLZ high dose (30 mg/kg). Our results proved that TIR had significant decrease of the serum ELISA of testosterone, marked disturbances in oxidative stress evaluated parameters as malondialdehyde (MDA), reduced glutathione (GSH), total antioxidant capacity (TAC), ELISA measurement of tumor necrosis factor alpha (TNFα) and interleukin 1 beta (IL1β) inflammatory mediators, apoptotic marker (caspase3) using western blotting, immunohistochemistry of hypoxia inducible factor-1α (HIF-1α) and vascular endothelial growth factor (VEGF). TIR reduced the protective agents as cyclic adenosine monophosphate (cAMP) and sirtuin-1 (SIRT1) by ELISA method with marked germinal cell apoptosis. The biochemical results were confirmed by the histopathological findings that showed marked decrease in both Johnsen's score and Cosentino's score. However, treatment with CLZ significantly reversed the profound TIR damaging effects, on the basis of its anti-inflammatory, anti-oxidant, and anti-apoptotic activities with recuperation of the testicular vascularity. Modulation of HIF/VEGF and cAMP/SIRT1 pathways showed a great role in mediating such effect.

Protective effects of crocin on testicular torsion/detorsion in rats

Oxidative stress, caused by extreme accumulation of un-scavenged reactive oxygen species, plays an integral role in the Ischemia-Reperfusion (I/R) injury to the testicles following testicular torsion. The current research aimed to examine the protective effects of crocin as a natural antioxidant on testicular I/R injury in rats. Animals were divided randomly into five groups (seven each): (1) sham group, (2) torsion/detorsion (T/D) group, (3) intact group with 100 mg/kg crocin, (4) and (5) T/D groups followed by treatment with two different doses of crocin (50 and 100 mg/kg (IP)). I/R injury was induced by 720° clockwise torsion of the left testicles for 2 h. After 24 h of reperfusion, blood samples and epididymal sperms were collected to measure biochemical (GPx, SOD, and MDA), hormonal (testosterone), and sperm parameters (total sperm recovery, motility, viability, and morphology). Moreover, affected testicles were subjected to histopathology examination. I/R injury caused a significant reduction in sperm characteristics (except for morphology) (P < 0.05), which could not be significantly improved by crocin administration at either dose (P > 0.05). Johnsen's testicular score, mean seminiferous tubular diameter, and germinal epithelial cell thickness were significantly decreased in the T/D group compared to the intact and sham groups. However, crocin could significantly improve the histopathological parameters in both treatment groups compared to the T/D group (P < 0.05). T/D reduced SOD and GPx activity and testosterone level significantly (except for GPx) compared to the sham group (P < 0.05). However, crocin administration could significantly reverse them. Also, crocin reduced the amount of MDA significantly in the high-dose treatment group in comparison to T/D group (P < 0.05). The results of the current study revealed that crocin could be a promising agent to protect against I/R injury following surgical correction of the testicular torsion.

Impaired macrophages and failure of steroidogenesis and spermatogenesis in rat testes with cytokines deficiency induced by diacerein

The role of cytokines in testicular function under normal conditions has not been completely understood. Here, we evaluated testicular macrophages (TM), steroidogenesis by Leydig cells (LC) and seminiferous tubules integrity in cytokines-deficient rat testes induced by diacerein, an anti-inflammatory drug that inhibits interleukin-1 (IL-1) and tumor necrosis factor-alpha (TNF-α). Male rats received daily 100 mg/kg of diacerein (DIAG; n = 8) or saline (CG; n = 8) for 30 days. Serum testosterone (T) levels were measured and the seminiferous tubule (ST) area, epithelial area (EA), frequency of damaged ST and number of Sertoli cells (SC) were evaluated. TUNEL method and immunoreactions for detection of pro-IL-1β, TNF-α, steroidogenic acute regulatory protein (StAR), 17β-hydroxysteroid dehydrogenase (17β-HSD), androgen receptor (AR) and scavenger receptor for hemoglobin-haptoglobin complexes (CD163), a TM marker, were performed. Testicular AR, 17β-HSD and IL-1β levels were detected by Western blot. Data were submitted to Student t test (p ≤ 0.05). In DIAG, T and testicular AR, 17β-HSD and IL-1β levels decreased significantly (p < 0.05). The number of TUNEL-positive interstitial cells increased and LC showed weak StAR, 17β-HSD and AR immunoexpression in association with reduced IL-1β immunoexpression and number of CD163-positive TM in the interstitial tissue from diacerein-treated rats. Numerous damaged ST were found in DIAG, and reduction in the EA were associated with germ cells death. Moreover, the number of SC reduced and weak AR and TNF-α immunoexpression was observed in SC and germ cells, respectively. The cytokines deficiency induced by diacerein impairs TM, LC and spermatogenesis, and points to a role of IL-1β in steroidogenesis under normal conditions. In the ST, the weak AR and TNF-α immunoexpression in SC and germ cells, respectively, reinforces the idea that TNF-α plays a role in the SC androgenic control.

Diacerein ameliorates testosterone-induced benign prostatic hyperplasia in rats: Effect on oxidative stress, inflammation and apoptosis

Benign prostatic hypertrophy (BPH) is a serious medical condition among elderly male population. BPH pathogenesis has been linked to inflammation, cellular proliferation, oxidative stress and apoptosis. Diacerein (DIA) is a FDA approved anthraquinone drug that is used to treat joint diseases such as osteoarthritis. DIA has been studied for its potent anti-inflammatory and antioxidant effects, yet its role in managing BPH has not been investigated. In this study, DIA administration for two weeks at 50 mg/kg in testosterone-induced BPH rats significantly reduced prostate weight and index. Moreover, prostatic biochemical and structural features in BPH rats were significantly improved upon DIA treatment. Mechanistically, DIA treatment associated prostatic anti-hyperplastic effects were linked to downregulation of Nrf-2/HO-1 axis, downregulation of inflammatory TNF-a, IL-1β, IL-6, downregulation of the cell proliferative marker PCNA and upregulation of caspase-3 levels. In addition, DIA treatment upregulated prostatic antioxidant GSH, the enzymatic SOD and CAT activities and reduced prostatic lipid peroxidation levels. Altogether, the present study provides evidence that DIA treatment might limit BPH progression via its potent anti-oxidant, anti-inflammatory, anti-proliferative and apoptosis inducing effects.

Co-administration of Salvia miltiorrhiza and verapamil inhibits detrimental effects of torsion/detorsion on testicular tissue in rats

Testicular torsion/detorsion is one of the important emergencies that requires fast surgical intervention. This study aimed to investigate the effects of Salvia miltiorrhiza hydroalcoholic extract combined with verapamil on testicular ischaemia/reperfusion damage in Wistar albino rats. All animals were distributed in 3 groups (n = 8), including the sham-operated group, torsion/detorsion (TD) group and torsion/detorsion + pretreatment with 200 mg/kg Salvia miltiorrhiza extract combined with 0.3 mg/kg verapamil (SMV) group. Oxidative stress biomarkers (MDA, GPx, CAT and TAC) both in plasma and testicular tissue, sperm parameters (motility, vitality, concentration and morphology) and histopathological parameters (MSTD, GECT, Johnson's score, Cosentino's score and testicular cell thickness) were assessed in all groups. Ischaemia/reperfusion significantly increased MDA and decreased GPx, CAT and TAC levels (p < .05). Pretreatment with SMV significantly increased GPx, CAT and TAC levels (p < .05). SMV group increased progressive sperm motility and vitality and reduced non-progressive motility of spermatozoon (p < .05). Testicular torsion significantly decreased all histopathological parameters compared to the sham group (p < .05). SMV pretreatment remarkably increased MSTD, GECT and Cosentino's score in comparison with the TD group (p < .05). A combination of Salvia miltiorrhiza with verapamil could reduce damages triggered by testicular torsion detorsion and improve sperm functionality parameters and oxidative stress defence systems.

Peroxynitrite activates NLRP3 inflammasome and contributes to hemorrhagic transformation and poor outcome in ischemic stroke with hyperglycemia

This study aims to test the hypothesis that peroxynitrite-mediated inflammasome activation could be a crucial player in the blood-brain barrier (BBB) disruption, hemorrhagic transformation (HT) and poor outcome in ischemic stroke with hyperglycemia. We used an experimental rat stroke model subjected to 90 min of middle cerebral artery occlusion plus 24 h or 7 days of reperfusion with or without acute hyperglycemia. We detected the production of peroxynitrite, the expression of NADPH oxidase, iNOS, MMPs and NLRP3 inflammasome in the ischemic brains, and evaluated infarct volume, brain edema, HT, neurological deficit score and survival rates. Our results show that: (1) Hyperglycemia increased the expression of NADPH oxidase subunits p47phox and p67phox, and iNOS, and the production of peroxynitrite. (2) Hyperglycemia increased infarct volume, aggravated the BBB hyperpermeability, induced brain edema and HT, and worsened neurological outcomes. These brain damages and poor outcome were reversed by the treatments of FeTmPyP (a representative peroxynitrite decomposition catalyst, PDC), peroxynitrite scavenger uric acid, and iNOS inhibitor 1400W. Furthermore, the activations of MMPs and NLRP3 inflammasome including pro/active-caspase-1 and IL-1β were inhibited both PDC and 1400W, indicating the roles of peroxynitrite in the inductions of MMPs and NLRP3 inflammasome in the ischemic brains under hyperglycemia. (3) NLRP3 inflammasome inhibitor MCC950, caspase-1 inhibitor VX-765 and IL-1β inhibitor diacerein attenuated brain edema, minimized hemorrhagic transformation and improved neurological outcome, demonstrating the roles of NLRP3 inflammasome in the hyperglycemia-mediated HT and poor outcome in the ischemic stroke rats with acute hyperglycemia. In conclusion, peroxynitrite could mediate activations of MMPs and NLRP3 inflammasome, aggravate the BBB damage and HT, and induce poor outcome in ischemic stroke with hyperglycemia. Therefore, targeting peroxynitrite-mediated NLRP3 inflammasome could be a promising strategy for ischemic stroke with hyperglycemia.

Diacerein protects rats with liver ischemia/reperfusion damage: Down-regulation of TLR4/ NFκ-B signaling pathway

PURPOSE

Liver ischemia-reperfusion (I/R) injury is an inescapable problem. Diacerein, a chondro-protective drug, has antioxidant and anti-inflammatory effects. Its effect on liver I/R injury has not yet been fully clarified. Therefore, the current study aimed to detect its hepatic protective effect with the explanation of possible underlying mechanisms.

METHODS

Adult male albino rats were assigned to 4 groups: sham group, diacerein pretreated sham group, I/R non-treated group, and I/R diacerein pretreated group. Serum liver enzymes, hepatic tissue oxidative stress parameters, inflammatory biomarkers mainly Toll-like receptors-4 (TLR4), and liver fatty acid binding protein (L-FABP) levels were determined. Histopathological examination of liver tissues and immunohistochemical studies of heat shock protein 70, nuclear factor-kappa B, and Cluster of Differentiation 68 were also done.

RESULTS

Diacerein pretreatment has the ability to restore the hepatic I/R damaging effect, proved by the reduction of serum liver enzymes, the decrease of the oxidative stress and hepatic inflammation via down-regulation of TLR4/ NFκ-B signaling pathway together with the restoration of L-FABP level and improvement of the histopathological and immunohistochemical study findings in the hepatic tissue.

CONCLUSION

These results suggested the hepatoprotective effect of diacerein relies on its antioxidant and anti-inflammatory effects reducing TLR4/ NFκ-B signaling pathway.

Sildenafil ameliorates Alzheimer disease via the modulation of vascular endothelial growth factor and vascular cell adhesion molecule-1 in rats

Alzheimer disease (AD) is a chronic neurodegenerative disease with multi-pathways pathogenesis. Sildenafil is a selective phosphodiesterase-5 inhibitor with a potential benefit in the treatment of AD. This study investigated the possible mechanisms underlying the effect of sildenafil in AD with emphasis on vascular endothelial growth factor (VEGF), and vascular cell adhesion molecule-1 (VCAM-1). Twenty-four adult male rats were classified into four groups; control group: received vehicles, sildenafil-control: received sildenafil (15 mg/kg/day, p.o.), AD group received Aluminum (25 mg/kg/day, p.o.), AD-treated group: received sildenafil (15 mg/kg/day, p.o.) for 6 weeks. AD was assessed by memory performance test and confirmed by histopathological examination and immunostaining of, neurogenesis marker nestin and α-synuclein. The levels of VEGF-A, VCAM-1, oxidative stress markers and TNF-α in brain tissue were evaluated. AD rats showed histopathological evidences of AD; along with increased latency time in the memory test. There was a decrease in VEGF-A, and an increase in VCAM-1, TNF-α, and oxidative stress markers. Immunohistochemical study showed a significant increase in α-synuclein and a significant decrease in nestin expressions in brain tissues. Sildenafil administration ameliorated the histopathological changes and decreased latency time. Such effect was associated with a decrease in VCAM-1, TNF-α and oxidative stress as well as an increase in VEGF-A. Sildenafil caused a significant increase in nestin and a decrease in α-synuclein immunostaining. These findings suggested a protective effect of sildenafil via modulation of VEGF-A, and VCAM-1.

Diacerein: Recent insight into pharmacological activities and molecular pathways

Diacerein is a symptomatic slow-acting drug in osteoarthritis (SYSADOA) and the active metabolite is rhein. It is a non-steroidal anti-inflammatory drug with unique pharmacological properties as anti-oxidant and anti-apoptosis. Diacerein has recently shown to have a potential role by mediating anti-inflammatory as well as anti-oxidant and anti-apoptosis in kidney injury, diabetes mullites, and a beneficial effect on pain relief. It may have a therapeutic role in cancer, ulcerative colitis, testicular injury and cervical hyperkeratosis. Furthermore, diacerein has a valuable addition in combination therapy as a synergetic agent. This review, the first of its kind, highlights the proposed roles of diacerein in osteoarthritis and discusses recent results supporting its emerging roles with a particular focus on how these new insights may facilitate the rational development of diacerein for targeted therapies in the future.

Diacerein Downregulates NLRP3/Caspase-1/IL-1β and IL-6/STAT3 Pathways of Inflammation and Apoptosis in a Rat Model of Cadmium Testicular Toxicity

The potential gonadal protective effect of diacerein (DCN) and its underlying mechanisms were studied in a rat model of cadmium-induced testicular toxicity. The rats received DCN (50 mg/kg/day, p.o.) for 10 days and one injection of CdCl₂ (2 mg/kg, i.p.) on day 9. Cadmium significantly declined serum testosterone and significantly raised interleukin-1β, interleukin-6, interleukin-18, tumor necrosis factor-α, caspase-1, phosphorylated signal transducer and activator of transcription-3 (pSTAT3), nuclear factor-κB p65, Bax, and caspase-3 in rat testes. DCN significantly ameliorated the changes in the biochemical measurements observed with CdCl₂ insult. Additionally, DCN preserved the normal testicular architecture, maintained spermatogenesis, and lowered the expression of NOD-like receptor family protein 3 (NLRP3) inflammasome in testes of rats that received CdCl₂. It was concluded that DCN significantly protected the gonads of male rats exposed to cadmium toxicity through modulation of NLRP3/caspase-1/IL-1β and IL-6/STAT3 pathways of inflammation and apoptosis.

Possible mechanisms mediating the protective effect of cilostazol in L-arginine induced acute pancreatitis in rats: role of cGMP, cAMP, and HO-1

Acute pancreatitis (AP) is an inflammatory disorder with a high mortality rate. Cilostazol is a selective phosphodiesterase-3 inhibitor drug that is commonly used as an antiplatelet, antithrombotic, and vasodilator drug. It exhibits antioxidant, anti-inflammatory, and anti-apoptotic activities, but its effect on AP has not been fully elucidated yet. The present study aimed to investigate the effects of cilostazol on L-arginine-induced AP and the possible protective mechanisms. A rat model of AP was established by a single i.p. injection of 3-g/kg L-arginine on day 13 of the experiment. The treated groups received a single daily oral dose of either 100 or 300 mg/kg/day for 14 consecutive days. Rats with AP showed histopathological changes of pancreatic tissue injury together with increased serum amylase enzyme activity and decreased serum insulin, pancreatic adiponectin, and cGMP levels. Moreover, AP rats showed increased pancreatic inflammatory biomarker (TNF-α, VCAM-1, and MPO) levels with decreased anti-inflammatory IL-10 levels. In addition, oxidative stress biomarkers (MDA and NO) were increased in AP with decreased antioxidant SOD activity and GSH level. Moreover, HO-1 immunostaining was increased in the AP group. Cilostazol pretreatment reversed the histopathological change; decreased the amylase activity and the levels of TNF-α, VCAM-1, and MPO; and increased the levels of insulin, adiponectin, cGMP, cAMP, and IL-10. Moreover, cilostazol decreased MDA and NO but increased SOD and GSH. Lastly, cilostazol increased the HO-1 immunostaining more than in the AP group. These data suggest that cilostazol protects against L-arginine-induced AP, which may be related to an increase in cGMP, cAMP, and upregulation of HO-1 with subsequent anti-inflammatory and antioxidant properties.

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.

Ameliorative effect of nicorandil in ovarian ischemia-reperfusion-induced injury in rats: role of potassium channel

Ovarian torsion is a gynecological emergency that leads to serious outcomes. Nicorandil (NIC) is an ATP-sensitive potassium (K_ATP) channel activator that protects the heart from ischemia. The current study aimed to investigate the role and mechanism of action of NIC in ovarian ischemia-reperfusion (OIR) and possible K_ATP participation. Twenty-four female albino rats were classified into 4 groups: sham control, OIR, OIR + NIC, OIR + NIC+ glibenclamide (GLB) groups. Serum anti-Müllerian hormone (AMH), ovarian malondialdehyde (MDA), total nitrites (NO_x) contents, and superoxide dismutase (SOD) activity were evaluated. Bax and Bcl2 mRNA were also assessed. Histological and immunohistochemical (anti-COX-2 and anti CD68) studies were done. The OIR non-treated group showed histopathological ovarian injury with decreased AMH level. Ovarian MDA, NO_x, and Bax mRNA and the expression of COX-2 and CD68 were increased; however, SOD activity and Bcl2 mRNA level were decreased by OIR. NIC significantly ameliorated the histopathological ovarian injury with the restoration of AMH level. NIC significantly corrected oxidative stress and apoptotic biomarkers with decreased COX-2 and CD68 immunostaining. GLB co-administration significantly decreased the protection afforded by NIC. These results imply that NIC has a protective role against OIR via antioxidant, anti-inflammatory, and anti-apoptotic effects and such protection relies, at least partially, on the K_ATP channel.

Protective effect of hydrogen sulfide on experimental testicular ischemia reperfusion in rats

AIM

Testicular torsion is an urgent urological condition. Ischemia-reperfusion (I/R) processes that occur after detorsion as a treatment for torsion are caused by testicular injury. The purpose of our study is investigating the protecting effect of hydrogen sulfide (H₂S) on the testicular ischemia reperfusion injury.

MATERIALS AND METHODS

Thirty-eight Wistar-Albino rats were divided randomly into 6 different groups: Control (6); sham (6); IR-E (6)-2 h of torsion and 4 h of reperfusion; IR-E + H₂S (6)-in addition to the IR-E group, 75 μmol/kg of sodium hydrogen sulfide (NaHS) was administered intraperitoneally 30 min before reperfusion; IR-L (7)-2 h of torsion and 24 h of reperfusion; IR-L + H₂S (7)-in addition to the IR-L group, 75 μmol/kg NaHS was administered intraperitoneally 30 min before reperfusion. Biochemically, nitric oxide (NO), malondialdehyde (MDA), superoxide dismutase (SOD), reductive glutathione (GSH), and tumor TNF-α levels were measured in the testis. Serum TNF-α levels were also measured. Hematoxylin and eosin (H & E) was used for histopathological staining and microscopic findings were examined. The Johnsen score was performed to assess spermatogenesis activity in the testis. Apoptosis protease activating factor-1 (Apaf-1) and inducible nitric oxide synthase (iNOS) activity were evaluated immunohistochemically as well. Statistical analyses were made by the Chi-squared test and one-way analysis of variance.

RESULTS

MDA and NO levels were significantly increased in the IR-L group compared with sham and which decreased by the addition of H₂S treatment to the IR-L group (p < 0.05) in biochemical evaluation. GSH vs SOD levels were decreased in the IR-L group compared with sham and which increased by the addition of H₂S treatment to the IR-L group, but this correlations were not statistically significant (p > 0.05). Tissue and serum TNF-α levels were significantly increased in the IR-E group compared with sham and which decreased by the addition of H₂S treatment to the IR-E group. Johnsen score was the lowest in IR-L group (p < 0.05). Apaf-1 and iNOS activity were significantly increased in the IR-L group compared with sham and which decreased by the addition of H₂S treatment to the IR-L group (p < 0.05) in immunohistochemical evaluation.

CONCLUSIONS

First, the authors would like to say that H₂S treatment is protective and it is against ischemia reperfusion injury in testicular torsion. The anti-inflammatory, antioxidant, and antiapoptotic properties of H₂S caused protective effect as shown in this study.

Picroside II attenuates ischemia/reperfusion testicular injury by alleviating oxidative stress and apoptosis through reducing nitric oxide synthesis

Purpose:

To investigate the effect of Picroside II on testicular ischemia and reperfusion (l/R) injury and the underlying mechanism.

Methods:

Sprague-Dawley rats were randomly divided into 4 groups: sham operated group (Sham), Sham with Picroside II treatment group (Sham+ Pic II), l/R group (l/R) and l/R with Picroside II treatment group (I/R+ Pic II). l/R model was established by rotating the left testis 720° in a clock-wise direction for 4 hours. The histopathologic and spermatogenetic evaluation was performed. The apoptosis changes and the levels of HO-1 (heme oxygenase-1), MPO (myeloperoxidase), NOX (NADPH oxidase), SOD (superoxide dismutase), XO (xanthine oxidase) and NOS (nitric oxide synthase) were measured.

Results:

The seminiferous tubules were damaged in l/R rats, but Picroside II alleviated the changes induced by l/R. The increased level of apoptosis was decreased by Picroside II (P=0.01, 9.05±0.35 vs. 4.85±0.25). The activities of HO-1, MPO, NOX, XO and MDA content were increased and the SOD activity was decreased in l/R (P<0.05) and could be reversed by Picroside II (P=0.03, 405.5±7.5 vs. 304±17U/mgprot; P=0.02, 0.99±0.05 vs. 0.52±0.04 mgprot; P=0.01, 260+7 vs. 189±2 mgprot; P=0.04, 10.95+0.55 vs. 8.75+0.35 U/mgprot; P=0.045, 6.8+0.7 vs. 3.75+0.35 mgprot; P=0.04, 44.5+3.5 vs. 57.5+3.5 mgprot). Western blot showed that the expression of iNOS, nNOS and eNOS were increased in l/R (P<0.05); however, they were decreased after Picroside II treatment (P<0.05).

Conclusion:

Picroside II attenuated testicular I/R injury in rats mainly through suppressing apoptosis and oxidative stress through reduction of nitric oxide synthesis.

The hepatoprotective effect of sitagliptin against hepatic ischemia reperfusion-induced injury in rats involves Nrf-2/HO-1 pathway

BACKGROUND

Oxidative stress and inflammation play a key role in the development of hepatic ischemia reperfusion (HIR)-induced injury. Nuclear factor-erythroid 2-related factor-2 (Nrf-2) is a main regulator of numerous genes, encoding cytoprotective molecules including heme oxygenase-1 (HO-1). Sitagliptin (Sit) is an incretin enhancer acting via inhibition of dipeptidyl peptidase-4 (DPP-4) enzyme. This study was undertaken to investigate the ability of Sit to prevent the hepatic pathological changes of HIR induced injury and to modify Nrf-2 and its target HO-1.

METHODS

Pringle's maneuver was used to induce total HIR in adult male rats that were randomly assigned into 4 groups. Group1 (sham-operated control), Group 2 (sham-operated + Sit-control group), Group 3 (HIR non-treated), and Group 4 (HIR + Sit). Alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activities together with hepatic contents of malondialdhyde (MDA), nitric oxide (NO) and reduced glutathione (GSH) and superoxide dismutase (SOD) activity were evaluated. Hepatic tissue mRNA of Nrf-2 and protein content of HO-1 along with histopathological examination and scoring of hepatic injury were performed.

RESULTS

Sit caused a significant reduction in ALT and AST activities together with attenuation of HIR-induced histopathological liver injury. Effect of Sit was associated with decreased hepatic level of MDA and NO with increased GSH level and SOD activity. Non-treated rats with HIR showed an increase in Nrf-2 mRNA expression and HO-1 content in hepatic tissue which was further increased by Sit treatment.

CONCLUSIONS

These results indicate that hepatoprotective activity of Sit against HIR is attributed at least in part to modulation of Nrf-2/ HO-1 signaling pathway.

Ameliorative effects of silymarin on HCl-induced acute lung injury in rats; role of the Nrf-2/HO-1 pathway

OBJECTIVES

Aspiration is a common cause of acute lung injury (ALI), which lacks an effective treatment. Inflammation and oxidative stress play key roles in ALI development. Silymarin is an active extract of Silybum marianum plant seeds (milk thistle). Silymarin has potent anti-inflammatory and antioxidant effects; however its role in aspiration induced ALI has not been investigated. The aim of this study is to investigate the role of silymarin in the treatment of hydrochloric acid (HCl) aspiration induced ALI and explores its mechanisms of action.

MATERIALS AND METHODS

The study included three groups of rats: Control non-treated group, ALI group (intra-tracheal HCl injected), and silymarin treated ALI group. White blood cells (WBCs) with differential count, oxidative stress parameters, B-cell lymphoma 2 (Bcl-2), transforming growth factor-beta (TGF-β), cyclooxygenase 2 (COX-2), nuclear factor erythroid 2-related factor-2 (Nrf-2), and heme oxygenase-1 (HO-1) were investigated. Lung tissue histopathology and immunohistochemical expression of survivin and proliferating cell nuclear antigen (PCNA) were also examined.

RESULTS

The results of the study showed that HCL caused histopathological changes in ALI with leukocytopenia and increased oxidative stress biomarkers. It increased TGF-β, up-regulated mRNA expression of COX-2, Nrf-2, and HO-1 and increased survivin and PCNA but decreased Bcl-2. Silymarin ameliorated the histopathological lung injury with further up-regulation of Nrf-2 and HO-1 mRNA and decreased the inflammatory and fibrotic parameters together with up-regulation of the anti-apoptotic and the proliferation parameters.

CONCLUSION

The protective effect of silymarin against ALI is mediated by Nrf-2/HO-1 pathway with subsequent antioxidant, anti-inflammatory, antiapoptotic, and proliferating activities.

Protective effect of dipeptidyl peptidase-4 inhibitors in testicular torsion/detorsion in rats: a possible role of HIF-1α and nitric oxide

Spermatic cord torsion is a serious and common urologic emergency. It requires early diagnosis for prevention of subfertility and testicular necrosis. Vildagliptin and sitagliptin are anti-diabetic drugs of the dipeptidyl peptidase-4 (DPP-4) inhibitors that have a protective role against cerebral ischemic stroke and cardiac ischemia reperfusion. This study aimed to investigate the role and mechanism of action of vildagliptin and sitagliptin in a model of testicular ischemia/reperfusion injury by testicular torsion/detorsion (T/D). Testicular T/D was done and vildagliptin and sitagliptin were administered either alone or in combination with nitric oxide synthase (NOS) inhibitor. Serum total cholesterol and testosterone were measured, while in testicular tissue testosterone, malondialdehyde (MDA) level, total antioxidant capacity (TAC), nitric oxide level, caspase-3, superoxide dismutase (SOD), hypoxia-inducible factor-1α (HIF-1α), tumor necrosis factor-α (TNF-α) and endothelial NOS (eNOS), and inducible NOS (iNOS) and neuronal NOS (nNOS) were measured. Histopathology of testicular tissue was done. Vildagliptin and sitagliptin increased serum testosterone, expression, and activity of SOD and testicular TAC. It also reduced total serum cholesterol, testicular MDA, caspase-3, HIF-1α, TNF-α, and expression of eNOS, iNOS, and nNOS. Vildagliptin and sitagliptin also improved histopathological picture of testicular tissue. NOS inhibitor produced similar result to DDP-4 inhibitors; however, its co-administration augmented the effect of vildagliptin and sitagliptin on these parameters. DPP-4 inhibitors, vildagliptin, and sitagliptin were protective against testicular T/D-induced injury mostly by anti-oxidative stress, and anti-apoptotic and anti-inflammatory actions that was augmented by NOS inhibition with a possible role for HIF-1α expression.

Sitagliptin protects male albino rats with testicular ischaemia/reperfusion damage: Modulation of VCAM-1 and VEGF-A

Twisting of the spermatic cord is considered a popular problem in the urological field, which may lead to testicular necrosis and male infertility. Sitagliptin, a glucose-lowering agent, proved to have a vindicatory function in myocardial and renal ischaemia/reperfusion (I/R), but its role in testicular I/R has not yet been studied. The current work investigates its capability to recover the testicular I/R injury with shedding more light on the mechanism of its action. Four groups were used: sham, sham pretreated with sitagliptin, I/R and sitagliptin/I/R-pretreated groups. The outcomes proved that I/R significantly decreased the serum testosterone, with a major increase in oxidative, inflammatory and nitrosative stress, along with a reduction in testicular vascular endothelial growth factor-A level with marked germinal cell apoptosis. However, pretreatment with sitagliptin significantly reversed the profound testicular I/R damaging effects, on the basis of its antioxidant, anti-inflammatory and anti-apoptotic activities with the ability of recuperation of the testicular vascularity.

Purine versus non-purine xanthine oxidase inhibitors against cyclophosphamide-induced cardiac and bone marrow toxicity in rats

BACKGROUND AND AIM

Cancer is a fatal and serious disease. Cyclophosphamide (CYC) is a commonly used anticancer drug. Cardiotoxicity and myelotoxicity are life-threatening side effects of CYC treatment. We aimed to evaluate the effect of the xanthine oxidase (XO) inhibitors, allopurinol (ALL) and febuxostat (FEB), on CYC-induced cardio- and hematopoietic toxicity in rats.

METHODS

ALL (100 mg/kg/day) or FEB (10 mg/kg/day) were administered orally to rats in the presence and absence of CYC (200 mg/kg kg i.p. single dose) treatment. Serum creatine kinase-MB creatine kinase myocardial band (CK-MB) and lactate dehydrogenase (LDH) activities were estimated. Complete blood counting (CBC), cardiac and bone marrow XO activity, malondialdehyde level, and superoxide dismutase activity were determined. Cardiac and bone marrow histopathological changes were also evaluated.

RESULTS

ALL and FEB significantly decreased CK-MB and LDH induced by CYC. Disturbed levels of XO, oxidative stress parameters, and CBC were also corrected by both XO inhibitors tested, with amelioration of cardiac histopathological changes caused by CYC. Treatment with FEB, but not ALL, prior to CYC challenges normalized bone marrow histopathological changes.

CONCLUSION

These results suggest that both XO inhibitors tested; ALL and FEB can ameliorate CYC-induced cardiotoxicity. However, only FEB can protect against CYC-induced myelotoxicity, whereas ALL, to the contrary, might aggravate it.