scholarly journals The Hypoxic Testicle: Physiology and Pathophysiology

2012 ◽  
Vol 2012 ◽  
pp. 1-15 ◽  
Author(s):  
Juan G. Reyes ◽  
Jorge G. Farias ◽  
Sebastián Henríquez-Olavarrieta ◽  
Eva Madrid ◽  
Mario Parraga ◽  
...  
Keyword(s):  
Germ Cell ◽  
Testicular Torsion ◽  
Oxygen Supply ◽  
Cell Function ◽  
Cell Damage ◽  
The Body ◽  
Body Core Temperature ◽  
Seminiferous Tubules ◽  
Low Oxygen ◽  
Complex Biological Process

Mammalian spermatogenesis is a complex biological process occurring in the seminiferous tubules in the testis. This process represents a delicate balance between cell proliferation, differentiation, and apoptosis. In most mammals, the testicles are kept in the scrotum 2 to 7°C below body core temperature, and the spermatogenic process proceeds with a blood and oxygen supply that is fairly independent of changes in other vascular beds in the body. Despite this apparently well-controlled local environment, pathologies such as varicocele or testicular torsion and environmental exposure to low oxygen (hypoxia) can result in changes in blood flow, nutrients, and oxygen supply along with an increased local temperature that may induce adverse effects on Leydig cell function and spermatogenesis. These conditions may lead to male subfertility or infertility. Our literature analyses and our own results suggest that conditions such as germ cell apoptosis and DNA damage are common features in hypoxia and varicocele and testicular torsion. Furthermore, oxidative damage seems to be present in these conditions during the initiation stages of germ cell damage and apoptosis. Other mechanisms like membrane-bound metalloproteinases and phospholipase A2 activation could also be part of the pathophysiological consequences of testicular hypoxia.

Zinc and selenium combination treatment protected diabetes-induced testicular and epididymal damage in rat

2020 ◽  
Vol 39 (9) ◽  
pp. 1235-1256 ◽  
Author(s):  
C Sahu ◽  
DK Dwivedi ◽  
GB Jena
Keyword(s):  
Glutathione Peroxidase ◽  
Germ Cell ◽  
Combination Treatment ◽  
Cell Damage ◽  
Combined Treatment ◽  
Tunel Assay ◽  
The Body ◽  
Terminal Deoxynucleotidyl Transferase ◽  
Feed Water ◽  
Related Factor

Diabetes increases the possibility of germ cell damage, hypogonadism, and male infertility. Diabetic condition negatively impacts zinc (Zn) and selenium (Se) levels in the body. Zn and Se are among the most important trace elements involved in the regulation of redox reaction, antioxidants enzymes activities, and DNA expression in a germ cell. The present study aimed to elucidate the combined effects of Zn and Se treatment on diabetes-induced germ cell damage in male Sprague Dawley rats. Type 1 diabetes was induced by the single intraperitoneal (i.p.) injection of streptozotocin (55 mg/kg). Zn (3 mg/kg, i.p.) and Se (0.5 mg/kg, i.p.) were administered daily for 8 consecutive weeks. All the animals were provided with normal feed and water throughout the study. The effects on germ cell damage were evaluated by body weight, feed-water intake, organ weight, sperm count, motility, sperm head morphology, biochemical analysis, histology, immunohistochemistry, halo assay, germ cell comet assay, testes terminal deoxynucleotidyl transferase deoxyuridine triphosphate nick end-labeling (TUNEL) assay, sperm TUNEL assay, serum protein pattern analysis, and subcellular analysis using transmission electron microscopy. Further, the expressions of nuclear erythroid-derived related factor 2, catalase, glutathione peroxidase 4, and glutathione peroxidase 5 were carried out to ascertain the mechanism of protection. The present results demonstrated that 8 weeks combined treatment of Zn (3 mg/kg, i.p.) and Se (0.5 mg/kg, i.p.) reduced diabetes-induced germ cell damage. This study further highlighted that Zn and Se combination treatment might be a better strategy for the germ cell protection in diabetes and deserve further investigation.

scholarly journals Hypoxia/HIF Modulates Immune Responses

Biomedicines ◽  
2021 ◽  
Vol 9 (3) ◽  
pp. 260
Author(s):  
Yuling Chen ◽  
Timo Gaber
Keyword(s):  
Immune Response ◽  
Cancer Progression ◽  
Immune Cells ◽  
Cell Function ◽  
Immune Cell ◽  
Adaptive Immune Response ◽  
Oxygen Availability ◽  
The Body ◽  
Low Oxygen ◽  
Adaptive Immune

Oxygen availability varies throughout the human body in health and disease. Under physiological conditions, oxygen availability drops from the lungs over the blood stream towards the different tissues into the cells and the mitochondrial cavities leading to physiological low oxygen conditions or physiological hypoxia in all organs including primary lymphoid organs. Moreover, immune cells travel throughout the body searching for damaged cells and foreign antigens facing a variety of oxygen levels. Consequently, physiological hypoxia impacts immune cell function finally controlling innate and adaptive immune response mainly by transcriptional regulation via hypoxia-inducible factors (HIFs). Under pathophysiological conditions such as found in inflammation, injury, infection, ischemia and cancer, severe hypoxia can alter immune cells leading to dysfunctional immune response finally leading to tissue damage, cancer progression and autoimmunity. Here we summarize the effects of physiological and pathophysiological hypoxia on innate and adaptive immune activity, we provide an overview on the control of immune response by cellular hypoxia-induced pathways with focus on the role of HIFs and discuss the opportunity to target hypoxia-sensitive pathways for the treatment of cancer and autoimmunity.

Mechanisms of Nickel-Induced Cell Damage in Allergic Contact Dermatitis and Nutritional Intervention Strategies

2020 ◽  
Vol 20 (7) ◽  
pp. 1010-1014 ◽  
Author(s):  
Dana Filatova ◽  
Christine Cherpak
Keyword(s):  
Lipid Peroxidation ◽  
Contact Dermatitis ◽  
Oxidative Damage ◽  
Allergic Contact Dermatitis ◽  
Cell Damage ◽  
Consumer Products ◽  
The Body ◽  
Cellular Damage ◽  
Nutritional Interventions ◽  
Allergic Contact

Background: Hypersensitivity to nickel is a very common cause of allergic contact dermatitis since this metal is largely present in industrial and consumer products as well as in some commonly consumed foods, air, soil, and water. In nickel-sensitized individuals, a cell-mediated delayed hypersensitivity response results in contact to dermatitis due to mucous membranes coming in long-term contact with nickel-containing objects. This process involves the generation of reactive oxidative species and lipid peroxidation-induced oxidative damage. Immunologically, the involvement of T helper (h)-1 and Th-2 cells, as well as the reduced function of T regulatory cells, are of importance. The toxicity, mutagenicity, and carcinogenicity of nickel are attributed to the generation of reactive oxygen species and induction of oxidative damage via lipid peroxidation, which results in DNA damage. Objective: The aim of this research is to identify nutritionally actionable interventions that can intercept nickel-induced cell damage due to their antioxidant capacities. Conclusion: Nutritional interventions may be used to modulate immune dysregulation, thereby intercepting nickel-induced cellular damage. Among these nutritional interventions are a low-nickel diet and an antioxidant-rich diet that is sufficient in iron needed to minimize nickel absorption. These dietary approaches not only reduce the likelihood of nickel toxicity by minimizing nickel exposure but also help prevent oxidative damage by supplying the body with antioxidants that neutralize free radicals.

scholarly journals Post-Transplant Diabetes Mellitus and Prediabetes in Renal Transplant Recipients: An Update

Nephron ◽  
2021 ◽  
pp. 1-13
Author(s):  
Ana Elena Rodríguez-Rodríguez ◽  
Esteban Porrini ◽  
Mads Hornum ◽  
Javier Donate-Correa ◽  
Raúl Morales-Febles ◽  
...  
Keyword(s):  
Diabetes Mellitus ◽  
Renal Transplant ◽  
Cell Function ◽  
Cell Damage ◽  
Current Evidence ◽  
Renal Transplant Recipients ◽  
Transplant Recipients ◽  
Post Transplant ◽  
Β Cell Function

Post-transplant diabetes mellitus (PTDM) is a frequent and relevant complication after renal transplantation: it affects 20–30% of renal transplant recipients and increases the risk for cardiovascular and infectious events. Thus, understanding pathogenesis of PTDM would help limiting its consequences. In this review, we analyse novel aspects of PTDM, based on studies of the last decade, such as the clinical evolution of PTDM, early and late, the reversibility rate, diagnostic criteria, risk factors, including pre-transplant metabolic syndrome and insulin resistance (IR) and the interaction between these factors and immunosuppressive medications. Also, we discuss novel pathogenic factors, in particular the role of β-cell function in an environment of IR and common pathways between pre-existing cell damage and tacrolimus-induced toxicity. The relevant role of prediabetes in the pathogenesis of PTDM and cardiovascular disease is also addressed. Finally, current evidence on PTDM treatment is discussed.

Seasonal changes in pancreatic B-cell function in euthermic yellow-bellied marmots

1985 ◽  
Vol 249 (2) ◽  
pp. R159-R165 ◽  
Author(s):  
G. L. Florant ◽  
A. K. Lawrence ◽  
K. Williams ◽  
W. A. Bauman
Keyword(s):  
Insulin Resistance ◽  
Body Weight ◽  
B Cell ◽  
Cell Function ◽  
Peripheral Resistance ◽  
The Body ◽  
Pancreatic B Cell ◽  
Peripheral Insulin Resistance ◽  
Body Weights ◽  
System Input

Fasting plasma insulin (PI) and glucose (PG) concentrations were measured throughout the body weight cycle of marmots. Animals gained weight during summer, and in late fall body weight peaked, after which they ceased feeding. Each month euthermic animals were injected intra-arterially with either dextrose (500 mg/kg) or porcine insulin (0.1 U/kg), and blood samples were collected over the subsequent 2 h. During weight gain fasting PI concentration and pancreatic B-cell response to injected dextrose increased markedly. Maximal insulin release to a dextrose challenge was measured during peak body weight or when body weight initially began to decline. The PG concentration after exogenous insulin administration was slight (less than 10%) in the fall but increased approximately 25% in the spring after marmots lost weight. Basal PG levels were not significantly different throughout the year. Basal fasting PI concentrations were significantly higher during the fall (P less than 0.01). It is suggested that in the fall, when marmots are obese, hyperinsulinemia and peripheral insulin resistance appear. Furthermore, in two animals with an increase in body weight of approximately 30% or less over the summer, peripheral resistance was demonstrable, albeit not as marked as in animals that appropriately doubled their body weights when given food ad libitum. Thus we hypothesize that factors other than adiposity, i.e., food intake, central nervous system input to the pancreatic B-cell, and/or changes in B-cell sensitivity to PG, may contribute to the observed peripheral insulin resistance and may be involved in body weight regulation.

CLASSIFICATION OF HUMAN FACIAL AND AURAL TEMPERATURE USING NEURAL NETWORKS AND IR FEVER SCANNER: A RESPONSIBLE SECOND LOOK

2005 ◽  
Vol 05 (01) ◽  
pp. 165-190 ◽  
Author(s):  
E. Y. K. NG ◽  
COLIN CHONG ◽  
G. J. L. KAW
Keyword(s):  
Neural Network ◽  
Body Temperature ◽  
False Negative ◽  
The Body ◽  
Body Core Temperature ◽  
Thermal Imager ◽  
Facial Skin ◽  
Thermal Imagers ◽  
Cardinal Symptom ◽  
Elevated Body Temperature

Severe Acute Respiratory Syndrome (SARS) is a highly infectious disease caused by a coronavirus. Screening to detect potential SARS infected subject with elevated body temperature plays an important role in preventing the spread of SARS. The use of infrared (IR) thermal imaging cameras has thus been proposed as a non-invasive, speedy, cost-effective and fairly accurate means for mass blind screening of potential SARS infected persons. Infrared thermography provides a digital image showing temperature patterns. This has been previously utilized in the detection of inflammation and nerve dysfunctions. It is believed that IR cameras may potentially be used to detect subjects with fever, the cardinal symptom of SARS and avian influenza. The accuracy of the infrared system can, however, be affected by human, environmental, and equipment variables. It is also limited by the fact that the thermal imager measures the skin temperature and not the body core temperature. Thus, the use of IR thermal systems at various checkpoints for mass screening of febrile persons is scientifically unjustified such as what is the false negative rate and most importantly not to create false sense of security. This paper aims to study the effectiveness of infrared systems for its application in mass blind screening to detect subjects with elevated body temperature. For this application, it is critical for thermal imagers to be able to identify febrile from normal subjects accurately. Minimizing the number of false positive and false negative cases improves the efficiency of the screening stations. False negative results should be avoided at all costs, as letting a SARS infected person through the screening process may result in potentially catastrophic results. Hitherto, there is lack of empirical data in correlating facial skin with body temperature. The current work evaluates the correlations (and classification) between the facial skin temperatures to the aural temperature using the artificial neural network approach to confirm the suitability of the thermal imagers for human temperature screening. We show that the Train Back Propagation and Kohonen self-organizing map (SOM) can form an opinion about the type of network that is better to complement thermogram technology in fever diagnosis to drive a better parameters for reducing the size of the neural network classifier while maintaining good classification accuracy.

Implications of body condition and seasonality on morphological and functional parameters of testes of Myotis nigricans (Chiroptera: Vespertilionidae)

2018 ◽  
Vol 30 (7) ◽  
pp. 1029
Author(s):  
Marcelo Ferreira ◽  
Aline Soldati ◽  
Sirlene S. S. Rodrigues ◽  
Laércio dos Anjos Benjamin
Keyword(s):  
Light Microscopy ◽  
Body Condition ◽  
Environmental Variables ◽  
Reproductive Strategies ◽  
Leydig Cells ◽  
Dry Season ◽  
The Body ◽  
Reproductive Capacity ◽  
Seminiferous Tubules ◽  
The Mean

The insectivorous bat Myotis nigricans is widely distributed throughout the Neotropics, including Brazil, and has a reproductive biology that is affected by climate and food availability. To evaluate the reproductive capacity of this species, morphofunctional parameters of the testes were correlated with environmental variables and the body condition of individuals captured. After bats had been killed, their testes were removed, fixed in Karnovsky’s fluid for 24 h and embedded in resin for evaluation by light microscopy. The mean annual tubulosomatic index (0.58%) and the percentage of seminiferous tubules in the testes (88.96%) were the highest ever recorded for the Order Chiroptera. The percentage of Leydig cells and volume of the cytoplasm of Leydig cells were higher in the rainy than dry season (80.62 ± 3.19% and 573.57 ± 166.95 μm, respectively; mean ± s.d.). Conversely, the percentage of nuclei of the Leydig cells in the dry season (26.17 ± 3.70%; mean ± s.d.) and the total number of Leydig cells (6.38 ± 1.84 × 109; mean ± s.d.) were higher in the dry season. The results of the present study could help in future conservation of these bats because they provide a better understanding of the bats’ reproductive strategies and how the species can adapt to changes.

Impaired Testicular Function in Patients With Carcinoma-In-Situ of the Testis

1999 ◽  
Vol 17 (1) ◽  
pp. 173-173 ◽  
Author(s):  
Peter Meidahl Petersen ◽  
Aleksander Giwercman ◽  
Steen W. Hansen ◽  
Jørgen G. Berthelsen ◽  
Gedske Daugaard ◽  
...  
Keyword(s):  
Testicular Cancer ◽  
Germ Cell ◽  
Leydig Cell ◽  
Carcinoma In Situ ◽  
Cell Function ◽  
Semen Quality ◽  
Sperm Concentration ◽  
Testicular Dysfunction ◽  
Leydig Cell Function

PURPOSE: To elucidate the biologic association between germ cell neoplasia and testicular dysfunction, through investigation of Leydig cell function and semen quality in men with carcinoma-in-situ (CIS) of the testis. PATIENTS AND METHODS: We examined two groups of men, unilaterally orchidectomized for testicular cancer. Biopsy of the contralateral testis had showed CIS in a group of 24 patients and no evidence of CIS in the other group of 30 patients. Semen quality and serum levels of testosterone, luteinizing hormone (LH), and follicle-stimulating hormone (FSH) were compared in these two groups of men after orchidectomy but before further treatment for testicular cancer. RESULTS: Significantly higher LH levels (median, 8.1 IU/L v 4.8 IU/L; P < .001) and generally lower testosterone levels (median, 12.5 nmol/L v 15.5 nmol/L; P = .13) were found in the CIS group. The proportion of patients with Leydig cell dysfunction was higher in the group of patients with CIS (11 of 24) than in the group of patients without (two of 30) (P = .01). Sperm concentration and total sperm count were significantly lower (P < .001) in patients with CIS (median, 0.03 × 106/mL and 0.10 × 106, respectively) than in patients without (median, 9.1 × 106/mL and 32 × 106, respectively), whereas the levels of FSH were significantly higher (P < .001) in the former group of men (median, 19.6 IU/L v 9.0 IU/L). CONCLUSION: Not only spermatogenesis but also Leydig cell function is impaired in testes with CIS. This impairment could be due to common factors in the pathogenesis of germ cell neoplasm and testicular dysfunction. Alternatively, CIS cells may have a negative impact on Leydig cell function.

Annual Meeting of the Section on Pediatric Urology

PEDIATRICS ◽  
1985 ◽  
Vol 76 (6) ◽  
pp. 1000-1003
Author(s):  
KENNETH I. GLASSBERG
Keyword(s):  
Animal Models ◽  
Annual Meeting ◽  
Testicular Torsion ◽  
Cell Damage ◽  
Basic Research ◽  
Testicular Biopsy ◽  
Pediatric Urology ◽  
Prepubertal Boys ◽  
Histologic Changes

The Section of Urology of the American Academy of Pediatrics met for three days in conjunction with the 53rd annual meeting of the Academy in Chicago. Papers and panel discussions that would be of interest to the pediatrician are summarized herein according to topic. As there has been an increasing number of basic research papers presented in recent years, the Section, this year, initiated a prize for basic research. Also new to the meeting was the awarding of the first annual Pediatric Urology Medal, which was given to Harry Spence for contributions made to the field. TESTICULAR TORSION Recent reports of unilateral testicular torsion have suggested that adverse effects may occur to the contralateral testicle, if the ischemic testicle is treated by surgical detorsion and left in place rather than removed.1-4 Three authors addressed this problem by investigating animal models. Animal Models In prepubertal rats undergoing experimentally produced testicular torsion, Rabinowitz and associates found histologic changes in the contralateral testicle. The changes in the contralateral testicle were dependent upon the duration of torsion and were significantly greater when the ischemic testicle was detorsed and left in place. The degree of histologic changes in the ischemic testicle, especially the degree of germ cell damage, was the best prediction of long-term damage to the contralateral testicle. In the animal model, these changes could be averted by removing the ischemic testicle. Although not going as far to recommend orchiectomy as the treatment of choice for all cases of torsion, Dr. Rabinowitz did suggest that a testicular biopsy in prepubertal boys with testicular torsion may be a reliable index to subsequent long-term contralateral damage if the ischemic testicle is detorsed and pexed rather than removed.

scholarly journals Male germ cell transplantation in livestock

2006 ◽  
Vol 18 (2) ◽  
pp. 13 ◽  
Author(s):  
J. R. Hill ◽  
I. Dobrinski
Keyword(s):  
Stem Cells ◽  
Germ Cell ◽  
Cell Transplantation ◽  
Large Scale ◽  
Developmental State ◽  
Male Germ Cell ◽  
Seminiferous Tubules ◽  
Cell Transfer ◽  
Donor Sperm ◽  
Germ Cell Transplantation

Male germ cell transplantation is a powerful approach to study the control of spermatogenesis with the ultimate goal to enhance or suppress male fertility. In livestock animals, applications can be expanded to provide an alternative method of transgenesis and an alternative means of artificial insemination (AI). The transplantation technique uses testis stem cells, harvested from the donor animal. These donor stem cells are injected into seminiferous tubules, migrate from the lumen to relocate to the basement membrane and, amazingly, they can retain the capability to produce donor sperm in their new host. Adaptation of the mouse technique for livestock is progressing, with gradual gains in efficiency. Germ cell transfer in goats has produced offspring, but not yet in cattle and pigs. In goats and pigs, the applications of germ cell transplantation are mainly in facilitating transgenic animal production. In cattle, successful male germ cell transfer could create an alternative to AI in areas where it is impractical. Large-scale culture of testis stem cells would enhance the use of elite bulls by providing a renewable source of stem cells for transfer. Although still in a developmental state, germ cell transplantation is an emerging technology with the potential to create new opportunities in livestock production.

Sign in / Sign up

Export Citation Format

Share Document