Mature Male Mice Research Articles

The Relation Between the Noise Stress Effects and Neurotransmitters, Sex Hormones Levels in the Male and Female Balb/c Mice

Many studies suggest that noise stress could damage many body systems such as nervous and endocrine systems, so the goal of this study was to demonstrate how the levels of neurotransmitters and sex hormones in mature male and female mice are affected by different noise stress exposure durations? In this study, 60 Balb/C mice (males and females) were used. Fifty mice were exposed to 90dB noise stress for 4h/daily and were scarified in different time points; 1,7,14,21, and 28 days while the rest 10mice were not exposed to noise stress and they serve as control. After the end of the experiment, the blood was collected and the serum samples were used to determine neurotransmitters levels, serotonin (5-HT) and noradrenaline (NA), and hormones levels included testosterone, estrogen and cortisol levels. The findings showed that neurotransmitters levels were significantly higher in mice exposed to noise stress for 1,8,14, and 21days which was non-significant decrease compared to the control in the 28-day stress group. While the levels of cortisone were continuously rising in the exposed noise stress mice groups with the length of duration, the levels of estrogen in female and testosterone in male were continuously decreasing. Interestingly, the levels of neurotransmitters and cortisol were significantly higher in females than males in all noise stress groups. Additionally, these effects completely differ after 28 days of noise exposure, which needs more future studies to prove the risk of exposure to this type of stress on the body systems.

C1473G Polymorphism in Tph2 Gene Affects Activation of Serotonin Metabolism in Mouse Brain 24 h after LPS Administration.

We studied the effect of the C1473G polymorphism in the Tph2 gene that reduces the activity of the tryptophan hydroxylase 2 in the brain on the severity of changes in motor activity (23 h after intraperitoneal administration of 0.8 mg/kg LPS or saline) and on the level of serotonin (5-HT) and its metabolite 5-hydroxyindoleacetic acid (5-HIAA) in the endings of 5-HT neurons in the cortex, hippocampus, and striatum (24 h after administration) of mature male mice of congenic lines B6-1473CC (high activity) and B6-1473GG (low activity). The state of the immune system in these structures was assessed by the expression of genes for proinflammatory cytokines IL-1β and TNF. LPS caused a decrease in motor and exploratory activities and increased the expression of the Il1b and Tnf genes in the studied brain structures in mice of both genotypes. LPS did not affect the level of 5-HT in any of the studied brain structures, but dramatically increased the level of 5-HIAA in these structures. The influence of the C1473G polymorphism on the intensity of the LPS-dependent increase in the level of 5-HIAA in the cortex and striatum was shown: in B6-1473CC mice this increase was more pronounced than in B6-1473GG mice. Demonstration of the influence of this polymorphism on the response of the 5-HT system after stimulation of the innate immunity is important for understanding of the role of tryptophan hydroxylase 2 in the mechanism of adaptation of the nervous system during infections and for predicting and reducing the risks of mental disorders.

Long-term intake of aspartame-induced cardiovascular toxicity is reflected in altered histochemical parameters, evokes oxidative stress, and trigger P53-dependent apoptosis in a mouse model.

Aspartame (ASP) is probably the best known artificial sugar substitute that is used widely in food. Many experimental studies have reported the toxicity of long-term administration of ASP in various organ tissues. However, there is little evidence available about the nature and mechanisms of the adverse effects of long-term consumption of ASP on the cardiovascular system. This study was conducted to evaluate the possible effects of ASP on heart tissue. For this study 36 mature male mice were divided into one control group and three groups which received respectively 40 mg/kg, 80 mg/kg and 160 mg/kg ASP orally, for 90 days. ASP at the doses of 80 and 160 mg/kg increased the serum content of malondialdehyde (MDA), but decreased serum nitric oxide (NO), creatine kinase (CK) and CK-MB, as well as blood superoxide dismutase (SOD) levels. Serum level of total anti-oxidant capacity (TAC) in blood was also reduced in serum at the dose of 80 mg/kg. Histochemical staining, including Periodic acid-Schiff, Masson's trichrome and Verhoeff-van Gieson staining, indicated that ASP at doses of 80 and 160 mg/kg reduced glycogen deposition and decreased the number of collagen and elastic fibres in the cardiac tissue. The cardiac expression of pro-apoptotic genes, including P53, Bax, Bcl-2 and Caspase-3, was modulated at the dose of 160 mg/kg. Moreover, transcription of Caspase-3 was up-regulated at the dose of 80 mg/kg. In conclusion, long-term consumption of ASP any higher than the acceptable daily intake (40 mg/kg) appears to act by promoting oxidative stress, has the potential to alter both histopathological and biochemical parameters, and induces P53-dependent apoptosis in cardiac tissue.

Manual versus automatic analysis of microglial density and distribution: a comparison in the hippocampus of healthy and lipopolysaccharide-challenged mature male mice

Microglia, the immune resident cells of the central nervous system (CNS), are now recognized as performing crucial roles for maintaining homeostasis and determining the outcomes of various pathological challenges across life. While brightfield microscopy is a powerful and established tool to study microglia-mediated mechanisms underlying neurological diseases, microglial density and distribution are some of the most frequently investigated parameters. Their quantitative assessment provides relevant clues regarding dynamic densitometric changes in the microglial population across various CNS regions. Investigators often rely on a manual identification and analysis of these cells within key regions of interest, which can be time-consuming and introduce an experimenter bias. Automation of this process, which has been gaining popularity in recent years, represents a potential solution to minimize both experimenter’s bias and time investment, thus increasing the efficacy of the experiment and uniformity of the collected data. We aimed to compare manual versus automatic analysis methods to determine whether an automatic analysis is efficient and accurate enough to replace a manual analysis in both homeostatic and pathological contexts (i.e., adult healthy and lipopolysaccharide-challenged adolescent male mice, respectively). To do so, we used a script that runs on the ImageJ software to perform microglial density analysis by automatic detection of microglial cells from brightfield microscopy images. The main core of the macro script consists in an automatic cell selection step using a threshold followed by a spatial analysis for each selected cell. The resulting data were then compared with the values obtained using a well-established manual method. Overall, the evaluation of the established automatic densitometry method with manual density and distribution analysis revealed similar results for the density and nearest neighbor distance in healthy adult mice, as well as density and distribution in lipopolysaccharide-challenged adolescent mice. Applying machine learning to the automatic process could further improve the accuracy and robustness of the method.

P-047 The effects of dietary branched-chain amino acids on mice semen parameters and plasma amino acids profile

Abstract Study question Are there any differences between the effect of each member of the branched-chain amino acids (BCAAs) on sperm parameters and plasma amino acids profile? Summary answer Valine supplementation had destructive effects on sperm parameters and viability. However, blood amino acids profile were similar among treatments. What is known already BCAAs, a group of three essential amino acids, have a crucial role on protein synthesis, besides being strongly associated with impaired glucose and fat metabolism. Although BCAAs supplements are one of the most demanding products for the fitness industry to increase the lean body mass and boost exercise performance, little information exists on the advantages and disadvantages of dietary BCAAs on male fertility. Study design, size, duration Fifty NMRI mature male mice were divided into five groups and were fed diets as follow: Control (CTR): 2.4% Beta-alanine, Leucine (Leu): 1.18% Leu + 1.2% Beta-alanine, Isoleucine (Ile): 0.58% Ile + 1.8% Beta-alanine, Valine (Val): 0.65% + 1.7% Beta-alanine, and BCAAs (Leu:Ile:Val ratio of 2:1:1): 2.4% BCAA: 1.18% Leu + 0.58% Ile + 0.65% Val. After 5 weeks, testes and epididymides were dissected, and sperm parameters and plasma amino acids profile were assessed. Participants/materials, setting, methods Semen parameters were evaluated by a Computer-Aided Semen Analysis (CASA) system. Plasma amino acids concentrations were determined by HPLC. Data were analyzed using SPSS and statistical differences among various groups were determined by ANOVA and Tukey’s post-hoc test. Main results and the role of chance Higher BCAAs intake, particularly Val, increased the destructive mechanisms on sperm viability. The results showed no significant difference on body weight after 40 days. Sperm concentration (8.4 vs. 4.5 ×106), progressive motility (51.5 vs. 27.2 %), and viability (67 vs. 56 % for CTR and Val group, respectively) decreased dominantly in the Val group compared to CTR (p≤0.05). The immotile parameter was significantly higher in the Val group compared to the CTR (p≤0.05). In addition, there were no significant differences on plasma amino acids profile. Limitations, reasons for caution The current study's limitation is that only one level of BCAAs was used. Given the potential role of Val on sperm cell death, further data on different levels of all BCAAs, especially Val administration and evaluation of the related mechanisms are needed. Wider implications of the findings The findings of our study show, for the first time, that individual levels of Ile and Leu have different effects on sperm parameters compared with all BCAAs or Val. More attention should be given to BCAAs supplementation and semen quality that was previously ignored. Trial registration number not applicable

Social Network Plasticity of Mice Parental Behavior.

Neural plasticity occurs during developmental stages and is essential for sexual differentiation of the brain and the ensuing sex-dependent behavioral changes in adults. Maternal behavior is primarily affected by sex-related differences in the brain; however, chronic social isolation even in mature male mice can induce maternal retrieving and crouching behavior when they are first exposed to pups. Social milieus influence the inherent behavior of adults and alter the molecular architecture in the brain, thereby allowing higher levels of associated gene expression and molecular activity. This review explores the possibility that although the development of neural circuits is closely associated with maternal behavior, the brain can still retain its neuroplasticity in adults from a neuromolecular perspective. In addition, neuronal machinery such as neurotransmitters and neuropeptides might influence sociobehavioral changes. This review also discusses that the neural circuits regulating behaviors such as parenting and infanticide (including neglect behavior), might be controlled by neural relay on melanin concentrating hormone (MCH)–oxytocin in the hypothalamus during the positive and negative mode of action in maternal behavior. Furthermore, MCH–oxytocin neural relay might contribute to the anxiolytic effect on maternal behavior, which is involved with reward circuits.

The anti-inflammatory and antioxidant effects of Montelukast on lung sepsis in adult mice.

One of the most complex clinical challenges facing medical practice is sepsis-induced lung dysfunction resulting from polymicrobial sepsis. Although many therapeutic approaches have been used in such clinical challenges, there is still further need for a new effective therapeutic approach. The objective of this study was to investigate if Montelukast could protect the lungs during polymicrobial sepsis by regulating inflammatory markers and the oxidative stress pathways. Twenty-four mature male Swiss-albino mice aged 8–12 weeks, with a weight of 20–30 g, were randomized into 4 equal groups (n=6), sham (laparotomy without cecal ligation and puncture (CLP)), CLP (laparotomy with CLP), vehicle 1 (equivalent volume of DMSO 1 hour prior to CLP), Montelukast (10 mg/kg IP 1 hour prior to CLP). Lung tissue pro-inflammatory mediators IL-6, IL-1β, IL-17, LTB-4 12(S) HETE, and oxidative stress were assessed using ELISA. The levels of F2 isoprostane were considerably greater in the sepsis group (p<0.05) as compared to the sham group, while Montelukast was significantly lower (p<0.05) in these inflammatory mediators and oxidative stress as compared to the sepsis group. Histologically, the lung tissue damage was significant (p<0.05) in all mice in the sepsis group, while Montelukast significantly reduced lung tissue injury (p<0.05). The current findings indicated that Montelukast could attenuate lung dysfunction during CLP-induced polymicrobial sepsis in male mice through their modulating effects on pro-inflammatory and oxidative stress downstream signalling pathways and subsequently decrease lung tissue cytokine concentrations (IL-1β, IL-6, IL-17, LTB-4, and 12(S)HETE).

Nephroprotective properties of chitosan/sodium lignosulfonate/Au nanoparticles in streptozotocin-induced nephropathy in mice: Introducing a novel therapeutic drug for the treatment of nephropathy

In this study, we report the green synthesis of nontoxic, stable, and small size gold nanoparticle by using chitosan/sodium lignosulfonate hydrogel with capping/reducing ability for the synthesis of CS/NaLS/Au NPs. The prepared bio-nanocomposite were characterized by advanced physicochemical techniques like Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), Energy Dispersive X-ray spectroscopy (EDX) and X-ray Diffraction (XRD) study. It has been established that CS/NaLS/Au NPs have a spherical shape with a mean diameter from 20 to 30 nm. Diabetes was induced by administration of 60 mg/kg of streptozotocin (STZ) intraperitoneally in 100 mature male mice and they were randomly divided into 5 groups. The negative control group received normal saline and treatment groups received glibenclamide with dose 0.5 mg/kg and 10 and 40 μg/kg of CS/NaLS/Au NPs through gavage for 50 days. In addition, one group considered as positive control (in treated-diabetic). On the last day, serum levels of samples blood glucose, urea and creatinine were measured. After tissue processing, 5 μm sections of the kidneys were prepared and they were stained by periodic acid Schiff (PAS) and used for stereological analysis. In the antioxidant test, the IC50 of CS/NaLS/Au NPs and BHT against DPPH free radicals were 117 and 86 µg/mL, respectively. In the cellular and molecular part of the recent study, the treated cells with CS/NaLS/Au NPs were assessed by MTT assay for 48 h about the cytotoxicity properties on normal (HUVEC) cell line. The increased levels of blood glucose and urea were decreased ( p < 0.05) significantly in CS/NaLS/Au NPs-treated groups as compared to the untreated diabetic. The kidney weight, kidney volume (Volume of cortex, medulla, glomerulus, proximal and distal tubules, collecting ducts, loop of Henle, interstitial tissues, and vessels) and kidney structures length (length of proximal and distal tubules, collecting ducts, loop of Henle, and vessels) decreased significantly ( p < 0.05) after treatment with high dose of CS/NaLS/Au NPs ( p < 0.05). According to the obtained results, CS/NaLS/Au NPs can regulates the levels of blood glucose and urea and inhibits from kidney damages in STZ-induced diabetic mice. This study suggested CS/NaLS/Au NPs as an antidiabetic and nephroprotective drug in the developing countries.

Development of Dihydroquercetin-based Oral tablets and Evalution of the General Toxic Effect

Development of Dihydroquercetin-based Oral tablets and Evalution of the General Toxic Effect

Deletion of IL-17ra in osteoclast precursors increases bone mass by decreasing osteoclast precursor abundance.

Metabolic bone diseases, such as osteoporosis, typically reflect an increase in the number and activity of bone-resorbing osteoclasts that result in a loss of bone mass. Inflammatory mediators have been identified as drivers of both osteoclast formation and activity. The IL-17 family of inflammatory cytokines has gained attention as important contributors to both bone formation and resorption. The majority of IL-17 cytokines signal through receptor complexes containing IL-17a receptor (IL-17ra); however, the role of IL-17ra signaling in osteoclasts remains elusive. In this study, we conditionally deleted Il17ra in osteoclast precursors using LysM-Cre and evaluated the phenotypes of skeletally mature male and female conditional knockout and control mice. The conditional knockout mice displayed an increase in trabecular bone microarchitecture in both the appendicular and axial skeleton. Assessment of osteoclast formation in vitro revealed that deletion of Il17ra decreased osteoclast number, which was confirmed in vivo using histomorphometry. This phenotype was likely driven by a lower abundance of osteoclast precursors in IL-17ra conditional knockout mice. This study suggests that IL-17ra signaling in preosteoclasts can contribute to osteoclast formation and subsequent bone loss.

Pretreatment with gonadotropin-releasing hormone antagonist protects against chemotherapy-induced testicular damage 'in mice.

Background:Testicular toxicity following chemotherapy is of increasing importance with the continuous improvement of survival rates. Gonadotropin-releasing hormone (GnRH) was suggested to protect testis against such toxicity; however, its suppressive quality and mechanism of action are still unclear. We examined whether and how pretreatment with GnRH antagonist protects against the testicular damage caused by chemotherapy.Methods:Mature male mice were injected subcutaneously eight times in 2-day intervals with either saline or GnRH antagonist (Cetrotide; 1 g/mg), followed by an intraperitoneal injection with either saline or cyclophosphamide (CTX;100 mg/kg BW) and sacrificed 2 weeks or 3 months later. Testicular weight, epididymis weight, epididymal sperm count and sperm motility were measured. Serum anti-Müllerian hormone (AMH) was measured by enzyme-linked immunosorbent assay. Immunohistochemistry (Ki-67), immunofluorescence (PCNA, CD34), terminal transferase-mediated deoxyuridine 5-triphosphate nick-end labeling (TUNEL) and computerized analysis were performed to examine testicular proliferation, apoptosis and vascularization. Quantitative real-time PCR was used to assess the amount of spermatogonial reserve (Id4 and Gfra1 mRNAs).Results:Pretreatment with GnRH antagonist transiently reduced testicular weight, epididymal weight, germinal proliferation and sperm count; it also abolished the permanent long-term effect of CTX on these parameters and prevented cyclophosphamide-induced testicular toxicity characterized by apoptosis and serum AMH increase and irreversible loss of spermatogonial reserve.Conclusions:Our findings imply that pretreatment with GnRH antagonist temporarily reduces spermatogenesis and may be used as pretreatment for reducing chemotherapeutic testicular toxicity.

Multi-Domain Touchscreen-Based Cognitive Assessment of C57BL/6J Female Mice Shows Whole-Body Exposure to 56Fe Particle Space Radiation in Maturity Improves Discrimination Learning Yet Impairs Stimulus-Response Rule-Based Habit Learning.

Astronauts during interplanetary missions will be exposed to galactic cosmic radiation, including charged particles like 56Fe. Most preclinical studies with mature, “astronaut-aged” rodents suggest space radiation diminishes performance in classical hippocampal- and prefrontal cortex-dependent tasks. However, a rodent cognitive touchscreen battery unexpectedly revealed 56Fe radiation improves the performance of C57BL/6J male mice in a hippocampal-dependent task (discrimination learning) without changing performance in a striatal-dependent task (rule-based learning). As there are conflicting results on whether the female rodent brain is preferentially injured by or resistant to charged particle exposure, and as the proportion of female vs. male astronauts is increasing, further study on how charged particles influence the touchscreen cognitive performance of female mice is warranted. We hypothesized that, similar to mature male mice, mature female C57BL/6J mice exposed to fractionated whole-body 56Fe irradiation (3 × 6.7cGy 56Fe over 5 days, 600 MeV/n) would improve performance vs. Sham conditions in touchscreen tasks relevant to hippocampal and prefrontal cortical function [e.g., location discrimination reversal (LDR) and extinction, respectively]. In LDR, 56Fe female mice more accurately discriminated two discrete conditioned stimuli relative to Sham mice, suggesting improved hippocampal function. However, 56Fe and Sham female mice acquired a new simple stimulus-response behavior and extinguished this acquired behavior at similar rates, suggesting similar prefrontal cortical function. Based on prior work on multiple memory systems, we next tested whether improved hippocampal-dependent function (discrimination learning) came at the expense of striatal stimulus-response rule-based habit learning (visuomotor conditional learning). Interestingly, 56Fe female mice took more days to reach criteria in this striatal-dependent rule-based test relative to Sham mice. Together, our data support the idea of competition between memory systems, as an 56Fe-induced decrease in striatal-based learning is associated with enhanced hippocampal-based learning. These data emphasize the power of using a touchscreen-based battery to advance our understanding of the effects of space radiation on mission critical cognitive function in females, and underscore the importance of preclinical space radiation risk studies measuring multiple cognitive processes, thereby preventing NASA’s risk assessments from being based on a single cognitive domain.

P–060 Dose- dependent mitigation of lead acetate toxicity in males on embryo development in female mice

Abstract Study question Does quercetin (75 or 100 mg/kg BW/day) co-administration with lead acetate to male mice affects embryonic development in female mice? Summary answer The low-dose quercetin (75 mg/kg BW/day) ameliorated the adverse effects of lead acetate on mouse embryogenesis. What is known already Lead causes male infertility by impacting on endocrine system and spermatogenesis, and may exert undesirable effects on the offspring. The currently approved treatment for lead poisoning is the use of chelating agents, which form an insoluble complex with lead and shield it from biological targets; thus, reducing its toxicity. One of the main mechanisms of lead-induced toxicity is oxidative stress, and it has been reported that natural antioxidants can reduce the heavy metals toxicity. The aim of the present study was to examine the protective effects of quercetin on the toxicity induced by lead acetate on the embryogenesis in mice. Study design, size, duration Sexually mature (eight-week-old) NMRI male mice (n = 24) were randomly divided into four groups (n = 6 per group) receiving (i) distilled water (control group); (ii) lead acetate (150 mg/kg BW/day) dissolved in deionized water (LA); (iii) lead acetate (150 mg/kg BW/day) + quercetin (75 mg/kg BW/day) (LQ75); (IV) lead acetate (150 mg/kg BW/day) + quercetin (100 mg/kg BW/day) (LQ100). Treatments were applied daily as oral gavages for one cycle of the seminiferous epithelium (35 days). Participants/materials, setting, methods At the end of treatment administration, the males were joined with super-ovulated females, and the retrieved zygotes were cultured for evaluation of the embryo development (at 2-cell, 4-cell, 8-cell, and blastocyst stages), and blastocyst cell number using differential staining (propidium iodide and bisbenzimide). After incubation of capacitated sperm with oocytes, an ultraviolet light microscope was used following 3 min incubation with 25 µg⁄mL bisbenzamide solution for fertilization assessment. Main results and the role of chance Lead acetate (LA) treatment of male mice decreased the 2-cell stage compared with the control group (P &amp;gt; 0.05). There was no difference between control and LQ75, and between LA and LQ100. The other stages of embryonic development were not significantly affected by the treatment. Overall, early embryonic development in the control and LQ75 mice were better than LQ100 and LA mice. The number of cells in the trophectoderm and inner-cell mass were not affected by treatments. However, the total blastocyst cell number in the control was higher than in the other groups; there was no significant difference between LQ100, LQ75 and LA groups. Fertilization rate was not affected by the treatments (P &amp;lt; 0.05). Quercetin acts as a potent antioxidant at low doses, but at high doses exerts a pro-oxidant action. According to previous reports, higher concentrations of quercetin increased apoptosis and necrosis while decreasing the activities of the antioxidant enzymes. Also, it has been suggested that quercetin might disrupt the endocrine system and interfere with Sertoli cell function and sperm motility. Limitations, reasons for caution A limitation of this study is narrow dose selection; more studies are needed to determine the effective dose of quercetin in ameliorating the lead toxicity. There are also side effects of lead-quercetin chelates such as metal redistribution, essential metal loss, accumulation and persistency in intracellular sites, and peroxidation. Wider implications of the findings: Lead administration adversely impacted on the embryogenesis; on the other hand, paternal quercetin co-administration somewhat ameliorated the adverse effects of lead on mice embryogenesis. Trial registration number Not applicable

Varenicline limits ischemia reperfusion injury following testicular torsion in mice

Torsion of the spermatic cord and the resulting testicular ischemia leads to the production of inflammatory cytokines and cell death due to impaired aerobic metabolism. Following reperfusion of the testis, a robust innate inflammatory response furthers tissue injury due to the production of reactive oxygen species and disruption of normal capillary function. Blunting the innate immune response with antioxidants, anti-inflammatory medications and targeted genetic interventions reduces long term testicular injury in animal models of torsion, however these approaches have limited clinical applicability. Mediated via α7 nACh receptors, the cholinergic anti-inflammatory pathway limits NFKB signaling and prevents renal fibrosis following warm renal ischemia. We identified varenicline as an FDA approved α7 nAChR agonist and hypothesized that varenicline administration would decrease long-term testicular atrophy and fibrosis in a murine model of testicular torsion. Using an established model, unilateral testicular torsion was induced in mature male CD1 mice by rotating the right testicle 720° for 2h. In the treatment group, 4 doses of varenicline (1mg/grm) were administered via intraperitoneal injection every 12h, with the first dose given 1h after the creation of testicular torsion. The acute inflammatory response was evaluated 48h following reperfusion of the testis. Long term outcomes were evaluated 30 days following testicular perfusion. 48h following reperfusion, the testis of animals treated with varenicline demonstrated a significant reduction in the inflammatory response as measured by the acute immune cell infiltrate, myeloperoxidase activity, concentration of reduced glutathione and expression of downstream NF-KB targets. 30 days following reperfusion, animals treated with varenicline, demonstrated decreased testicular atrophy (Summary Figure), fibrosis and expression of pro-fibrotic genes. Activation of a central immunosuppressive cascade with varenicline after the onset of testicular torsion reduces ischemia reperfusion injury and prevents long term testicular atrophy and fibrosis. Further studies are needed to define the optimum dose and varenicline administration regimen. Our results suggest that varenicline offers a novel, FDA approved, adjunct to the current management of testicular torsion.

Lymphocytic Choriomeningitis Virus Alters the Expression of Male Mouse Scent Proteins.

Mature male mice produce a particularly high concentration of major urinary proteins (MUPs) in their scent marks that provide identity and status information to conspecifics. Darcin (MUP20) is inherently attractive to females and, by inducing rapid associative learning, leads to specific attraction to the individual male’s odour and location. Other polymorphic central MUPs, produced at much higher abundance, bind volatile ligands that are slowly released from a male’s scent marks, forming the male’s individual odour that females learn. Here, we show that infection of C57BL/6 males with LCMV WE variants (v2.2 or v54) alters MUP expression according to a male’s infection status and ability to clear the virus. MUP output is substantially reduced during acute adult infection with LCMV WE v2.2 and when males are persistently infected with LCMV WE v2.2 or v54. Infection differentially alters expression of darcin and, particularly, suppresses expression of a male’s central MUP signature. However, following clearance of acute v2.2 infection through a robust virus-specific CD8 cytotoxic T cell response that leads to immunity to the virus, males regain their normal mature male MUP pattern and exhibit enhanced MUP output by 30 days post-infection relative to uninfected controls. We discuss the likely impact of these changes in male MUP signals on female attraction and mate selection. As LCMV infection during pregnancy can substantially reduce embryo survival and lead to lifelong infection in surviving offspring, we speculate that females use LCMV-induced changes in MUP expression both to avoid direct infection from a male and to select mates able to develop immunity to local variants that will be inherited by their offspring.

Effects of cisplatin and acacetin on total antioxidant status, apoptosis and expression of OCTN3 in mouse testis

ABSTRACT Cisplatin is a chemotherapeutic medication that also exhibits toxic effects on normal cells. Acacetin (ACA) is an herbal compound that exhibits anticancer properties with few side effects. We investigated the use and side effects of ACA and cisplatin on the male reproductive system. Mature male mice were divided into six groups: control group treated with DMSO, cisplatin group treated with 1 mg/kg cisplatin and three ACA groups treated with 10, 25 or 50 mg/kg ACA. All treatments were applied for three days. A final experimental group was treated with 50 mg/kg ACA for 10 days. At the end of the experiment, animals were sacrificed and reactive oxygen species (ROS), total antioxidant capacity (TAC), OCTN3 gene expression and apoptosis were measured in testis. TAC and OCTN3 gene expression were decreased, while ROS and apoptosis were increased in cisplatin group compared to other groups. All ACA groups exhibited decreased apoptosis and ROS levels, and increased TAC and OCTN3 gene expression compared to the cisplatin treated mice. ACA caused fewer adverse effects in testicular tissue than cisplatin. ACA appears to improve the oxidant-antioxidant system, accelerates cell regeneration and inhibits apoptosis.

Maintenance of muscle mass in adult male mice is independent of testosterone.

Testosterone is considered a potent anabolic agent in skeletal muscle with a well-established role in adolescent growth and development in males. However, the role of testosterone in the regulation of skeletal muscle mass and function throughout the lifespan has yet to be fully established. While some studies suggest that testosterone is important for the maintenance of skeletal muscle mass, an understanding of the role this hormone plays in young, adult, and old males with normal and low serum testosterone levels is lacking. We investigated the role testosterone plays in the maintenance of muscle mass by examining the effect of orchiectomy-induced testosterone depletion in C57Bl6 male mice at ages ranging from early postnatal through old age (1.5-, 5-, 12-, and 24-month old mice). Following 28 days of testosterone depletion, we assessed mass and fiber cross-sectional-area (CSA) of the tibialis anterior, gastrocnemius, and quadriceps muscles. In addition, we measured global rates of protein synthesis and degradation using the SuNSET method, western blots, and enzyme activity assays. Twenty-eight days of testosterone depletion resulted in reduced muscle mass in the two youngest cohorts, but had no effect in the two oldest cohorts. Mean CSA decreased only in the youngest cohort and only in the tibialis anterior muscle. Testosterone depletion resulted in a general increase in proteasome activity at all ages. No change in protein synthesis was detected at the terminal time point. These data suggest that within physiological serum concentrations, testosterone may not be critical for the maintenance of muscle mass in mature male mice; however, in young mice testosterone is crucial for normal growth.

Dysregulation of erythropoiesis and altered erythroblastic NMDA receptor-mediated calcium influx in Lrfn2-deficient mice.

LRFN2 encodes a synaptic adhesion-like molecule that physically interacts with N-methyl-D-aspartate (NMDA) receptor 1 and its scaffold proteins. Previous studies in humans and mice have demonstrated its genetic association with neurodevelopmental disorders such as learning deficiency and autism. In this study, we showed that Lrfn2-deficient (KO) mice exhibit abnormalities of erythropoietic systems due to altered NMDA receptor function. In mature Lrfn2 KO male mice, peripheral blood tests showed multilineage abnormalities, including normocytic erythrocythemia, and reduced platelet volume. Colony forming unit assay using bone marrow cells revealed decreases in the counts of erythrocyte progenitors (CFU-E) as well as granulocytes and monocyte progenitors (CFU-GM). Whole bone marrow cell staining showed that serum erythropoietin (EPO) level was decreased and EPO receptor-like immunoreactivity was increased. Flow cytometry analysis of bone marrow cells revealed increased early erythroblast count and increased transferrin receptor expression in late erythroblasts. Further, we found that late erythroblasts in Lrfn2 KO exhibited defective NMDA receptor-mediated calcium influx, which was inhibited by the NMDA receptor antagonist MK801. These results indicate that Lrfn2 has biphasic roles in hematopoiesis and is associated with the functional integrity of NMDA receptors in hematopoietic cells. Furthermore, taken together with previous studies that showed the involvement of NMDA receptors in hematopoiesis, the results of this study indicate that Lrfn2 may regulate erythropoiesis through its regulatory activity on NMDA receptors.

Ablation of AMPK-Related Kinase MPK38/MELK Leads to Male-Specific Obesity in Aged Mature Adult Mice.

Murine protein serine-threonine kinase 38 (MPK38)/maternal embryonic leucine zipper kinase (MELK) is implicated in diverse biological processes, including the cell cycle, apoptosis, and tumorigenesis; however, its physiological role is unknown. Using mice lacking MPK38 (MPK38-/-), we found that MPK38-/- male, but not female, mice (7 months of age) became obese while consuming a standard diet, displayed impairments in metabolism and inflammation, became more obese than wild-type mice while consuming a high-fat diet, and exhibited no castration/testosterone replacement-induced metabolic changes. The adenoviral restoration of MPK38 ameliorated the obesity-induced adverse metabolic profile of the obese male, but not female, mice. Seven-month-old MPK38-/- males displayed typical postcastration concentrations of serum testosterone with an accompanying decrease in serum luteinizing hormone (LH) levels, suggesting a role for MPK38 in the age-related changes in serum testosterone in aged mature adult male mice. The stability and activity of MPK38 were increased by dihydrotestosterone but reduced by estradiol (E2). These findings suggest MPK38 as a therapeutic target for obesity-related metabolic disorders in males.

Ameliorative effects of deferiprone and tetraethylammonium salt of salinomycinic acid on lead-induced toxicity in mouse testes.

In this study, we compare the effects of deferiprone (Def) and tetraethylammonium salt of salinomycinic acid (Sal) on lead (Pb)-induced toxicity in testes of Pb-exposed mice. Mature male ICR mice were allocated into four groups as follows: untreated control mice (ctrl)-received distilled water for 4 weeks; Pb-exposed mice (Pb)-subjected to 14-day Pb (II) nitrate administration at dose 80 mg/kg body weight (b.w.); Pb + Def group-Pb-exposed mice, treated with 20 mg/kg b.w. Def for 2 weeks; and Pb + Sal group-Pb-intoxicated mice, treated with 16 mg/kg b.w. Sal for 14 days. The results demonstrated that Pb exposure significantly increased blood and testicular Pb concentrations, decreased testicular calcium (Ca) content, significantly elevated testicular levels of magnesium (Mg), zinc (Zn), and selenium (Se) but did not significantly affect the endogenous contents of phosphorous (P) and iron (Fe) compared with untreated controls. Pb intoxication induced disorganization of the seminiferous epithelium. Def or Sal administration reduced blood Pb and testicular Pb concentrations in Pb-exposed mice compared with the Pb-intoxicated group. Mg, Zn, and Se concentrations in testes of Pb-exposed mice, treated with Def or Sal, remained higher compared with the untreated controls. Sal significantly increased testicular P concentration compared with untreated controls and significantly elevated the testicular Ca and Fe concentrations compared with the toxic control group. Both chelating agents improved testicular morphology to a great extent. The results demonstrate the potential of both compounds as antidotes for treatment of Pb-induced impairment of male reproductive function.