Effect of allopurinol on germ cell apoptosis following testicular ischemia-reperfusion injury in a rat

Role of EGF/ERK1/2/HO-1 axis in mediating methotrexate induced testicular damage in rats and the ameliorative effect of xanthine oxidase inhibitors

Objectives: Methotrexate (MTX) is commonly used in the management of several malignancies and autoimmune disorders; however, testicular damage is one of the most detrimental effects of MTX administration. The current the protective effect of xanthine oxidase inhibitors either purine analogue; allopurinol (ALL) or non-purine analogue; febuxostat (FEB) in testicular injury induced by MTX in rats.Materials and methods: Thirty-two rats were randomly allocated to four groups; control (received vehicles), MTX (received single dose, 20 mg/kg, i.p.), MTX + ALL (received MTX plus ALL) and MTX + FEB (received MTX plus ALL). ALL and FEB were administered orally at 100- and 10 mg/kg, respectively for 15 days. Total and free testosterone were measured in serum. In addition, total antioxidant capacity (TAC), epidermal growth factor (EGF), malondialdehyde (MDA), tumor necrosis factor-α (TNF-α), extracellular signal-regulating kinase1/2 (ERK1/2), and total nitrite/nitrate (NOx) end products were measured in testicular tissues. At the same time, immunoexpression of HO-1in testicular tissue was measured. Histopathological examination was done.Results: ALL and FEB increased total and free serum testosterone. Both drugs showed a significant reduction in testicular MDA, NOx, TNF-α levels with an increase in TAC, EGF, and ERK1/2 levels in testicular tissue. Furthermore, both drugs enhanced HO-1 immunoexpression in testicular tissue. All these findings were parallel to the preservation of normal testicular architecture in rats treated with ALL and FEB.Conclusion: All and FEB were equally protective against testicular damage induced by MTX through anti-inflammatory, anti-apoptotic, and antioxidant actions. Their effects might be through activation of the EGF/ERK1/2/HO-1 pathway.

The effect of hydroethanolic extract of Matricaria chamomilla on the reproductive system of male rats exposed to formaldehyde

Formaldehyde is a common agent in our surrounding environment and can adversely affect the male reproductive system. In this study, the effectiveness of Matricaria chamomilla (MC) extract as an antioxidant was investigated in rats treated with formaldehyde. Thirty-two male Wistar rats were randomly divided into six groups: F (10 mg/kg formaldehyde), M200 (200 mg/kg MC extract), M500 (500 mg/kg MC extract), FM200 (10 mg/kg formaldehyde and 200 mg/kg MC extract), FM500 (10 mg/kg formaldehyde and 500 mg/kg MC extract) and control group (0.9% normal saline). Formaldehyde and MC extract were administered daily for 30 consecutive days via intraperitoneal injection. Hormonal status, sperm parameters, testis tissue histology, germinal cells apoptosis and stereological analyses of testis tissue were investigated. Testosterone and LH levels were significantly increased in FM200, FM500, F200 and F500 groups compared to F group (p ≤ 0.05). Sperm count, motility and viability were significantly enhanced in FM200, FM500, F200 and F500 groups compared to F group (p ≤ 0.05). A decrease in the number of apoptotic germ cells in FM200, FM500, M200 and M500 groups (p ≤ 0.05) was evident. In particular, the MC extract in dose 500 mg/kg is seen to reduce the adverse effects of formaldehyde on the reproductive system of male rats.

The teratogenicity of allopurinol: A comprehensive review of animal and human studies

Allopurinol is widely used in the management of multiple disorders including gout, kidney stones and inflammatory bowel disease. Despite of long-term experience, its safety in pregnancy has been debated due to reports on possible teratogenicity. We aimed to review the literature on the safety of allopurinol in pregnancy and offspring. In animals, allopurinol induced species-specific reproductive toxicity. In humans, a total of 53 allopurinol exposed infants were reported in the literature. Major congenital malformations were reported in two cases with a comparable pattern of multiple abnormalities. Five other infants had minor birth defects. In conclusion, the association between allopurinol and teratogenicity appears to be weak and limited to two reports with uncertain causality. However, the available data are insufficient to make a certain judgement, and as allopurinol treatment evolves, report and prospective follow-up of all exposed infants (i.e. deviant and normal cases) should be encouraged.

Testicular compartment syndrome: an overview of pathophysiology, etiology, evaluation, and management

Testicular compartment syndrome (TCS) refers to the impairment of microcirculation in the testicle due to either increased venous resistance or extraluminal compression, which leads to hypoxia. TCS releases oxidants through hypoxia and ischemia/reperfusion injury (IRI). The pathophysiology, etiology, evaluation, and management of TCS are reviewed. Based on the properties of TCS, specific causes, e.g., varicocele, hydrocele, orchitis, cryptorchidism, and scrotal hernia, are suggested and categorized. The oxidant-induced stress from TCS may explain the correlations between these causes and infertility. A chief shortcoming of current imaging modalities is that they detect TCS late after it has progressed to impair the macrocirculation of the testicle. We propose frequent sequential periodic power Doppler ultrasonography to monitoring for earlier detection. Intraoperatively, TCS can be diagnosed by the dull purple appearance of a hypoxic testicle and by tissue pressures above 30 mmHg. When compartment pressure is low, the underlying etiology must be promptly treated. During acute presentation, an incision of the resilient tunica albuginea may be necessary. A great challenge of treating TCS is restoring microcirculation while minimizing IRI; concomitant antioxidant therapy secondary to treatment may be effective and harmless at the least. Because testicular oxidant stress is common in infertility and since TCS can cause such a stress, TCS may be a larger factor in infertility than currently suspected.

Xanthine oxidoreductase: a journey from purine metabolism to cardiovascular excitation-contraction coupling

Xanthine oxidoreductase (XOR) is a ubiquitous complex cytosolic molybdoflavoprotein which controls the rate limiting step of purine catabolism by converting xanthine to uric acid. It is known that optimum concentrations of uric acid (UA) and reactive oxygen species (ROS) are necessary for normal functioning of the body. The ability of XOR to perform detoxification reactions, and to synthesize UA and reactive oxygen species (ROS) makes it a versatile intra- and extra-cellular protective "housekeeping enzyme". It is also an important component of the innate immune system. The enzyme is a target of drugs against gout and hyperuricemia and the protein is of major interest as it is associated with ischemia reperfusion (I/R) injury, vascular disorders in diabetes, cardiovascular disorders, adipogenesis, metabolic syndrome, cancer, and many other disease conditions. Xanthine oxidoreductase in conjugation with antibodies has been shown to have an anti-tumor effect due to its ability to produce ROS, which in turn reduces the growth of cancer tissues. Apart from this, XOR in association with nitric oxide synthase also participates in myocardial excitation-contraction coupling. Although XOR was discovered over 100 years ago, its physiological and pathophysiological roles are still not clearly elucidated. In this review, various physiological and pathophysiological functional aspects of XOR and its association with various forms of cancer are discussed in detail.