Nupr1 deficiency downregulates HtrA1, enhances SMAD1 signaling, and suppresses age-related bone loss in male mice.

Nuclear protein 1 (NUPR1) is a stress-induced protein activated by various stresses, such as inflammation and oxidative stress. We previously reported that Nupr1 deficiency increased bone volume by enhancing bone formation in 11-week-old mice. Analysis of differentially expressed genes between wild-type (WT) and Nupr1-knockout (Nupr1-KO) osteocytes revealed that high temperature requirement A 1 (HTRA1), a serine protease implicated in osteogenesis and transforming growth factor-ß signaling was markedly downregulated in Nupr1-KO osteocytes. Nupr1 deficiency also markedly reduced HtrA1 expression, but enhanced SMAD1 signaling in in vitro-cultured primary osteoblasts. In contrast, Nupr1 overexpression enhanced HtrA1 expression in osteoblasts, suggesting that Nupr1 regulates HtrA1 expression, thereby suppressing osteoblastogenesis. Since HtrA1 is also involved in cellular senescence and age-related diseases, we analyzed aging-related bone loss in Nupr1-KO mice. Significant spine trabecular bone loss was noted in WT male and female mice during 6-19 months of age, whereas aging-related trabecular bone loss was attenuated, especially in Nupr1-KO male mice. Moreover, cellular senescence-related markers were upregulated in the osteocytes of 6-19-month-old WT male mice but markedly downregulated in the osteocytes of 19-month-old Nupr1-KO male mice. Oxidative stress-induced cellular senescence stimulated Nupr1 and HtrA1 expression in in vitro-cultured primary osteoblasts, and Nupr1 overexpression enhanced p16ink4a expression in osteoblasts. Finally, NUPR1 expression in osteocytes isolated from the bones of patients with osteoarthritis was correlated with age. Collectively, these results indicate that Nupr1 regulates HtrA1-mediated osteoblast differentiation and senescence. Our findings unveil a novel Nupr1/HtrA1 axis, which may play pivotal roles in bone formation and age-related bone loss.

Whole-cage randomization for animal studies with unequal cage or group sizes.

Following good statistical practice, in vivo study investigators allocate animals into two or more treatment groups using a randomization routine to eliminate selection bias and balance known and unknown confounding factors. For some studies, however, randomization at the individual animal level cannot be implemented. For example, for studies that involve co-housed male mice, an animal-level randomization can place unfamiliar mice together in the same cage, which can trigger fighting. To meet the ethical obligations to enhance the welfare of an animal used in science, the experimental procedures are, therefore, often modified, and male mice, possibly from the same brood, may be housed together. It follows that animal allocation into groups must proceed at the whole-cage level. Given the small sample sizes in animal studies, controlling baseline variables can be quite challenging. The difficulty greatly increases with a whole-cage randomization restriction. When the number of animals per cage or the treatment group sizes are unequal, there is no algorithm in the literature to perform the task. We propose a novel, fast, and reliable algorithm to provide a whole-cage randomization that balances one or more baseline variables across groups. The algorithm was applied to a realistic example dataset.

Infection of Trichinella spiralis Affects the Reproductive Capacity of ICR/CD-1 Male Mice by Reducing the Urine Pheromone Contents and Sperm Quality.

Female mice can discriminate the urinary odors of male mice due to their olfactory acuity. Parasitic infection or subclinical infection can decrease the odor attractiveness of male mice and finally lead to aversion or avoidance responses in odor selection for female mice. Trichinella spiralis is a kind of tissue-parasitizing nematode that causes trichinellosis, a zoonotic parasitic disease that spreads throughout the world. However, the reproductive injury caused by Trichinella spiralis infection was not fully revealed. In this study, we explored the effect of Trichinella spiralis infection on the reproductive capacity in ICR/CD-1 male mice. We identified eight volatile compounds in urine by GC-MS analysis, and the results indicated that the contents of dimethyl sulfone, Z-7-tetradecen-1-ol, 6-Hydroxy-6-methyl-3-heptanone and (S)-2-sec-butyl-4,5-dihydrothiazole were significantly downregulated after parasitic infection, which might lead to the reduction of attractiveness of male mice urine to females. On the other hand, parasitic infection decreased sperm quality and downregulated the expression levels of Herc4, Ipo11, and Mrto4, and these genes were strongly related to spermatogenesis. In summary, this study revealed that the reproductive injury caused by Trichinella spiralis infection in ICR/CD-1 male mice could be associated with a decrease in urine pheromone content and sperm quality.

Serotonin 5-HT7 receptor overexpression in the raphe nuclei area produces antidepressive effect and affects brain serotonin system in male mice.

Heterodimerization between 5-HT7 and 5-HT1A receptors seems to play an important role in the mechanism of depression and antidepressant drug action. It was suggested that the shift of the ratio between 5-HT1A /5-HT7 hetero- and 5-HT1A /5-HT1A homodimers in presynaptic neurons toward 5-HT1A /5-HT1A homodimers is one of the reasons of depression. Consequently, the artificial elevation of 5-HT7 receptor number in presynaptic terminals might restore physiological homo-/heterodimer ratio resulting in antidepressive effect. Here we showed that adeno-associated virus (AAV)-based 5-HT7 receptor overexpression in the midbrain raphe nuclei area produced antidepressive effect in male mice of both C57Bl/6J and genetically predisposed to depressive-like behavior ASC (antidepressant sensitive cataleptics) strains. These changes were accompanied by the elevation of 5-HT7 receptor mRNA level in the frontal cortex of C57Bl/6J and its reduction in the hippocampus of ASC mice. The presence of engineered 5-HT7 receptor in the midbrain of both mouse strains was further demonstrated. Importantly that 5-HT7 receptor overexpression resulted in the reduction of 5-HT1A receptor level in the membrane protein fraction from the midbrain samples of C57Bl/6J, but not ASC, mice. 5-HT7 receptor overexpression caused an increase of 5-HIAA/5-HT ratio in the midbrain and the frontal cortex of C57Bl/6J and in all investigated brain structures of ASC mice. Thus, 5-HT7 receptor overexpression in the raphe nuclei area affects brain 5-HT system and causes antidepressive effect both in C57Bl/6J and in "depressive" ASC male mice. Obtained results indicate the involvement of 5-HT7 receptor in the mechanisms underlying depressive behavior.

Effects of dietary supplementation of different oils and conjugated linoleic acid on the reproductive and metabolic aspects of male mice.

The present study was carried out to examine first, if diets enriched with 320 g of the base diet with common dietary oils including fish oil, olive oil, hydrogenated sunflower seed (H-SFS) oil, flaxseed oil and sunflower seed oil (SFS) could induce weight gain and alter reproductive and metabolic characteristics of male mice. Second, whether the addition of conjugated linoleic acid (CLA, 10% of the diet) could ameliorate any negative effects. In this cross-sectional study, 90 four-week-old male NMRI mice were used in two consecutive experiments. A high level of dietary oils negatively affected some reproductive and metabolic characteristics of male mice (p < 0.05), specifically, sunflower seed oil enrichment resulted in higher HDL levels and apoptosis of germinal epithelial cells. An olive oil-enriched diet caused an increase in plasma triglyceride concentrations and germinal cell apoptosis, as well as a decrease in sperm concentration and perturbed spermatogenesis. When CLA was fed in conjunction with dietary oils it successfully mitigated some of the negative reproductive and metabolic characteristics. We conclude that male reproductive processes are affected by high dietary oils, even before signs of obesity are evident. Inclusion of dietary CLA may provide some benefit to offset negative effects, although further studies are required.

Age-related changes in endogenous glucocorticoids, gonadal steroids, endocannabinoids and their ratios in plasma and hair from the male C57BL/6 mice.

Age-related level changes of hormones, endocannabinoids and their ratios are of pathophysiological significance for understanding functions, activities and interactions of the endocrine systems, including the hypothalamic-pituitaryadrenal (HPA), hypothalamic-pituitary-gonadal (HPG) axes and endogenous cannabinoid system (ECS). The present study aimed to investigate the age-dependent fluctuations of glucocorticoids, gonadal steroids, endocannabinoids and their ratios from 21 days to 10 months in both plasma and hair from the male C57BL/6 mice. A novel framework based on the liquid chromatography-tandem mass spectrometry was developed to simultaneously determine ten hormones and two endocannabinoids in plasma and hair. Results showed that glucocorticoids, corticosterone (CORT), aldosterone (ALD), 11-dehydrocorticosterone (11-DHC), gonadal steroids, progesterone (P), dehydroepiandrosterone (DHEA), testosterone (T) and dihydrotestosterone (DHT) in plasma were unimodally fluctuated (ps < 0.001) along age with the maximum value at 2.7-month-old. In contrast, the other two gonadal steroids, estrone (E1) and estradiol (E2) were declined with age (ps < 0.001). Differently, endocannabinoids, N-arachidonoyl-ethanolamine (AEA) and 1-arachydonoyl glycerol (1-AG) showed nadir and zenith values at 2.7-month-old and 3.4-month-old, respectively (ps < 0.001). Additionally, the ratios of CORT to 11-DHC and ALD in plasma were dropped similarly with age (ps < 0.001). The ratios of 1-AG to AEA, and of T to A4 and DHT, and of DHEA to A4 were unimodally changed (ps < 0.001) along age with maximum value at 2.7- or 3.4-month-old. In contrast, the ratios of E2 to T and E1 to A4 were decreased with age (ps < 0.05). The rest six ratios that reflected the interactions among the three endocrine systems, were similar age-dependent and showed nadir and zenith values at 2.7-month-old and 3.4-month-old, respectively (ps < 0.05). Most importantly, these findings in light of age-related changing patterns in plasma were repeated in hair, suggesting that the fi41-ndings in the two matrices were mutually validated. However, it was worth noting that their magnitude of levels in the two bio-matrices were markedly different. The current findings could provide reliable hormone and endocannabinoid signatures with age on neuroendocrine profiles as well as their ratios for the male C57BL/6 mice.

Tramadol Biological Effects: 4: Effective Therapeutic Efficacy of Lagenaria siceraria Preparation (Gamal & Aref1) and Melatonin on Cell Biological, Histochemical, and Histopathological Changes in the Kidney of Tramadol-Induced Male Mice.

Tramadol is used worldwide and is listed in many medical guidelines to treat both acute and chronic pains. There is a growing evidence of abuse of tramadol in some African and West Asian countries. Tramadol has some side effects. The present study designed to follow up the treatment of the cellular responses which might be induced in the kidney of tramadol mice. Treated mice received daily injection of tramadol dose (125 µg/100 g b.wt) for 20 and 40 days. Other mice received tramadol for 40 days and then were divided into three groups: the first received distilled water, the second received Lagenaria siceraria, and the third received melatonin daily for 40 days. Both the daily injection of tramadol for 20 and 40 days resulted in radical, extensive, and severe alterations in the normal histological architecture of the kidney. Treatment with Lagenaria siceraria or melatonin after tramadol administration for a long-term, markedly changed the collagen content and other chemical components, that may reach nearly normal levels. Such findings propose that although tramadol has many cytological and histopathological side effects on the kidneys of male mice, the treatments via Lagenaria siceraria and melatonin have effective therapeutic impacts on the tramadol side effects.

Molecular mechanisms associated with oxidative damage in the mouse testis induced by LaCl3.

China is the world's largest rare earth producer and exporter, previous studies have shown that rare earth elements can cause oxidative damage in animal testis. However, the molecular mechanisms underlying these observations have yet to be elucidated. In this paper, male mice were fed with different doses (10, 20, and 40 mg/kg BW) of LaCl3 for 90 consecutive days, regulatory role of nuclear factor erythroid-2 related factor 2 (Nrf-2)/antioxidant response element (ARE) pathway in testicular oxidative stress induced by LaCl3 were investigated. Analysis showed that LaCl3 exposure could lead to severe testicular pathological changes and apoptosis in spermatogenic cells, it up-regulated the peroxidation of lipids, proteins and DNA, and induced the excessive levels of reactive oxygen species (ROS) production in mouse testis, reduced the activities of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and glutathione S epoxide transferase (GST) as well as the glutathione (GSH) content. Furthermore, exposure to LaCl3 also downregulated the expression of Nrf2 and its target gene products, including heme oxygenase 1 (HO-1), glutamate-cysteine ligase catalytic subunit (GCLC), NAD(P)H dehydrogenase [quinine] 1(NQO1), protein kinase C (PKC), and phosphatidylinositol 3-kinase (PI3K), but upregulated the expression of Kelch-like ECH-related protein 1 (Keap1) in damaged mouse testes. Collectively, our data imply that the oxidative damage induced by LaCl3 in testis was related to inhibition of the Nrf-2/AREs pathway activation.

Sex Differences in Photoprotective Responses to 1,25-Dihydroxyvitamin D3 in Mice Are Modulated by the Estrogen Receptor-ß.

Susceptibility to photoimmune suppression and photocarcinogenesis is greater in male than in female humans and mice and is exacerbated in female estrogen receptor-beta knockout (ER-ß-/-) mice. We previously reported that the active vitamin D hormone, 1,25-dihydroxyvitamin D3 (1,25(OH)2D), applied topically protects against the ultraviolet radiation (UV) induction of cutaneous cyclobutane pyrimidine dimers (CPDs) and the suppression of contact hypersensitivity (CHS) in female mice. Here, we compare these responses in female versus male Skh:hr1 mice, in ER-ß-/-/-- versus wild-type C57BL/6 mice, and in female ER-blockaded Skh:hr1 mice. The induction of CPDs was significantly greater in male than female Skh:hr1 mice and was more effectively reduced by 1,25(OH)2D in female Skh:hr1 and C57BL/6 mice than in male Skh:hr1 or ER-ß-/- mice, respectively. This correlated with the reduced sunburn inflammation due to 1,25(OH)2D in female but not male Skh:hr1 mice. Furthermore, although 1,25(OH)2D alone dose-dependently suppressed basal CHS responses in male Skh:hr1 and ER-ß-/- mice, UV-induced immunosuppression was universally observed. In female Skh:hr1 and C57BL/6 mice, the immunosuppression was decreased by 1,25(OH)2D dose-dependently, but not in male Skh:hr1, ER-ß-/-, or ER-blockaded mice. These results reveal a sex bias in genetic, inflammatory, and immune photoprotection by 1,25(OH)2D favoring female mice that is dependent on the presence of ER-ß.

Effects of maternal exposure to arsenic on social behavior and related gene expression in F2 male mice.

BACKGROUND: Arsenic is a developmental neurotoxicant. It means that its neurotoxic effect could occur in offspring by maternal arsenic exposure. Our previous study showed that developmental arsenic exposure impaired social behavior and serotonergic system in C3H adult male mice. These effects might affect the next generation with no direct exposure to arsenic. This study aimed to detect the social behavior and related gene expression changes in F2 male mice born to gestationally arsenite-exposed F1 mice. METHODS: Pregnant C3H/HeN mice (F0) were given free access to tap water (control mice) or tap water containing 85 ppm sodium arsenite from days 8 to 18 of gestation. Arsenite was not given to F1 or F2 mice. The F2 mice were generated by mating among control F1 males and females, and arsenite-F1 males and females at the age of 10 weeks. At 41 weeks and 74 weeks of age respectively, F2 males were used for the assessment of social behavior by a three-chamber social behavior apparatus. Histological features of the prefrontal cortex were studied by ordinary light microscope. Social behavior-related gene expressions were determined in the prefrontal cortex by real time RT-PCR method. RESULTS: The arsenite-F2 male mice showed significantly poor sociability and social novelty preference in both 41-week-old group and 74-week-old group. There was no significant histological difference between the control mice and the arsenite-F2 mice. Regarding gene expression, serotonin receptor 5B (5-HT 5B) mRNA expression was significantly decreased (p < 0.05) in the arsenite-F2 male mice compared to the control F2 male mice in both groups. Brain-derived neurotrophic factor (BDNF) and dopamine receptor D1a (Drd1a) gene expressions were significantly decreased (p < 0.05) only in the arsenite-F2 male mice of the 74-week-old group. Heme oxygenase-1 (HO-1) gene expression was significantly increased (p < 0.001) in the arsenite-F2 male mice of both groups, but plasma 8-hydroxy-2'-deoxyguanosine (8-OHdG) and cyclooxygenase-2 (COX-2) gene expression were not significantly different. Interleukin-1ß (IL-1ß) mRNA expression was significantly increased only in 41-week-old arsenite-F2 mice. CONCLUSIONS: These findings suggest that maternal arsenic exposure affects social behavior in F2 male mice via serotonergic system in the prefrontal cortex. In this study, COX-2 were not increased although oxidative stress marker (HO-1) was increased significantly in arsnite-F2 male mice.

Novel catheter design enables transurethral catheterization of male mice.

The male mouse is underrepresented in research of the urinary tract due to the difficulty of transurethral catheterization. As a result, there is a lack of analysis of sex differences in urinary tract research. Here, we present a novel catheter design and technique that enables urethral catheterization of male mice for bladder inoculation. Our catheterization technique uses the resistance met at the level of the external urinary sphincter and prostate to guide the retraction, positioning, and advancement of the catheter into the urinary bladder. We have shown that this method can be used to reproducibly catheterize 12 male mice with minimal urogenital trauma but cannot be used as a cystometric technique. This method will facilitate the expansion of research into sex differences in various genitourinary conditions that require transurethral catheterization of mice.

Genipin improves reproductive health problems caused by circadian disruption in male mice.

BACKGROUND: Circadian rhythm disruption impacts a wide range of physiological processes, including fertility. However, the effect of circadian disruption on male spermatogenesis and fertility, and treatments for these effects have been largely unexplored at the molecular level. METHODS: In this study, we examined the effects of genipin on improving the reproductive health problems caused by circadian disruption. Three groups of animals were fed under different conditions: control group (normal T cycle with saline), group of shortened T cycles (Light/Dark = 4 hours/4 hours) with saline, and a group of shortened T cycles with genipin by oral gavage. The male fertility was evaluated by fertility study and pups parameters analysis after successful sexual behavior and mating with female mice. We sacrificed the treated animals after 5 or 10 weeks and collected the testis, sperm and serum for histological analysis, sperm motility assay, and serum hormone detection, respectively. Furthermore, the effect of genipin was assessed by detection of progesterone secretion and steroidogenic key proteins expression, including StAR and CYP11A1, in mouse Leydig tumor MLTC-1 cells. RESULTS: Male mice exposed to shortened light-dark cycles, much shorter than 24 hours, had reduced fertility with decreased sperm concentrations and sperm motility. Male mice under circadian disruption have reduced testis size and abnormal morphology, leading to lower fertility rates, reduced litter size and pup body weight. Treatment with exogenous genipin, a natural plant-derived compound, alleviated circadian disruption-induced damage to fertility and spermatogenesis and normalized testosterone, dihydrotestosterone (DHT), and androstenedione (ASD) levels in the male mice. The levels of key proteins involved in steroidogenesis, StAR and CYP11A1, were reduced in mouse testes after the circadian disruption, but genipin treatment restored the reduction. The mRNA expression of SRD5A1, which encodes an androgen synthesis enzyme, was also upregulated by genipin treatment. Furthermore, genipin treatment showed a positive effect on steroidogenesis in MLTC-1 cells, resulting in an increase in hormone secretion and the upregulation of StAR and CYP11A1. CONCLUSIONS: Our results showed an association between circadian disruption and reproductive health problems in male mice and indicated that treatments with genipin have positive effects on the reproductive health of male mice with circadian rhythm disorders.

Evaluation of the protective effects of icariin on nicotine-induced reproductive toxicity in male mouse -a pilot study.

BACKGROUND: Nicotine, a pharmacologically active component of tobacco adversely affects the male reproductive system and fertility whereas icariin (ICA), the main active ingredient in Epimedium herba has been used in the treatment of several male reproductive problems. This study aimed at evaluating the protective or ameliorative effect of ICA against reproductive toxicity induced by intraperitoneal injection of nicotine in mice. METHODS: Using simple random allocation, forty male mice were randomly divided into 4 groups: control (received 0.35 mL physiological saline via gastric gavage), nicotine (0.75 mg/kg BW/day intraperitoneally), ICA (75 mg/kg BW/day gastric gavage), and nicotine plus ICA (nicotine, 0.75 mg/kg BW/day intraperitoneally + ICA, 75 mg/kg BW/day gastric gavage) group. After 35 days of treatment, the mice were weighed, sacrificed, and their reproductive organs (testis and epididymis) were collected and examined for further studies. RESULTS: The nicotine-treated group showed significantly decreased epididymal sperm density and serum testosterone concentration relative to the control group. Nicotine also caused oxidative damage shown by significant reduction in the activities of antioxidant enzymes and elevation in Malondialdehyde (MDA) levels. ICA on the other hand, improved the reduction in sperm density, hormone levels, and activities of antioxidant enzymes altered in the nicotine treated mice. CONCLUSIONS: These findings indicate that nicotine-induced reproductive toxicity and oxidative damage on male reproductive tissues could be attenuated by ICA.

The glucagon-like peptide-1 receptor agonist, exendin-4, reduces sexual interaction behaviors in a brain site-specific manner in sexually naïve male mice.

Besides reducing food intake and controlling energy balance, glucagon-like peptide-1 (GLP-1) suppresses the reinforcing properties of palatable foods and addictive drugs. This reduction in reward involves activation of GLP-1 receptors (GLP-1R) within areas processing natural and artificial rewards, including the laterodorsal tegmental area (LDTg), ventral tegmental area (VTA) and nucleus accumbens (NAc) shell. These areas are part of a neurocircuitry mediating reward from addictive drugs and natural rewards including sexual behaviors. The male sexual encounter with a female includes three different stages: a pre-sexual interaction phase with social behaviors, which is followed by a sexual interaction phase with mounting and intromission of the female, and ends with a post-sexual interaction phase characterized by self-grooming behaviors. Albeit GLP-1 modulates reward, the influence of GLP-1R activation on sexual interaction is unknown. Thus, we infused the GLP-1R agonist, exendin-4 (Ex4), into sub-regions of the reward neurocircuitry in sexually naïve male mice and recorded their novel interaction with an estrus female. We found that Ex4 into the LDTg, posterior VTA or NAc shell reduces pre-sexual interaction behaviors and activation of GLP-1R in the LDTg or posterior VTA decreases sexual interaction behaviors. Contrarily, Ex4 infusion into anterior VTA does not influence these behaviors. Furthermore, self-grooming behaviors are not influenced by activation of GLP-1R in the aforementioned areas. These data highlight that activation of GLP-1R in reward-related areas reduces different aspects of the sexual interaction chain and further supports a role of the GLP-1R in social behaviors.

Study on the damage of sperm induced by nickel nanoparticle exposure.

As a new type of nanomaterials, nickel nanoparticles (Ni NPs) have been widely used by human beings, whose exposure probability was greatly increasing. Many studies have shown that Ni NPs can induce apoptosis, oxidative stress and DNA damage. Nowadays, male reproductive health is an important public health problem, which is a hot topic in toxicological research. In the present study, to protect reproductive health, the effect of Ni NPs exposure on spermatogenesis injury was assessed, understanding the toxicity and safety of Ni NPs. Sixty ICR male mice with 20 ± 2 g were randomly divided into five groups. The experimental groups were treated with 5 mg/kg, 15 mg/kg and 45 mg/kg Ni NPs. The reproductive toxicity of Ni NPs on male mice was evaluated by the indexes of testicular organ coefficient, testicular marker enzyme, sperm motility and histopathology. As a result, the somatic index of testis and epididymis increased in each group. Compared with the control group, the activity of testicular markers increased and the sperm motility index decreased in the low-, middle- and high-dose groups. Pathological results indicated that various cell apoptosis and disordered arrangement of cells occurred in the seminiferous tubules of the exposed groups. In conclusion, the findings of this study suggest that Ni NPs have certain damage to spermatogenesis in mice.

[Injury of procymidone on testis and sperm in the male adolescent mice].

OBJECTIVE: To investigate the damage of procymidone to penile, testis and sperm in adolescent male mice. METHODS: 4-week-old male ICR mice were allocated randomly to the treatment groups and the control group, with 8 mice in each group. Procymidone was administered to mice by gavage with dose 50 mg/kg(low dose), 100 mg/kg and 200 mg/kg, while the control group was given only an equal volume of soybean oil. On the 11 th days, the mice were sacrificed by spinal dislocation, their body masses were weighed, and the anogenital distance(AGD), testicular volume and penis length were measured. Furthermore the weight of the testes, epididymis and penis were weighed, the organ coefficients were calculated, and then a testis on one side and 1/2 penis tissue were fixed in 4% paraformaldehyde and used for histology analysis. The testis on the other side and the remaining 1/2 penis were used to detect androgen content and Caspase-3, Caspase-9, Caspase-12 and Bax gene expression. At the same time, one epididymis was randomly selected to detect sperm motility, density and morphology. RESULTS: The weight, penis length and testicular volume of mice in each experimental group did not change significantly, while the weight of testes and epididymis and testicular and epididymal coefficients of mice in the high-dose group decreased significantly(P<0. 05). The testis seminiferous tubules of every treatment group showed different degrees of degeneration, spermatogenic cell damage, and decreased number of luminal sperm. Meanwhile, medium and high dose treatment groups showed hyperplasia of testicular stromal cells. However, there was no significant pathologic change in penile tissue in every treatment group. The sperm density of mice in the middle and high dose groups was lower than that of the control group(P<0. 05), and the sperm deformity rate in the two groups was significantly higher than that of the control group(P<0. 01), while the sperm motility of every dose treatment group was lower than that of the control(P<0. 05). The testosterone in the testis of the middle and high dose groups were high than the control(P<0. 001), while there was no statistically significant difference of the testosterone among all the groups in the penis(P>0. 05). In addition, the expression of pro-apoptotic genes Caspase-3, Caspase-9, Caspase-12 and Bax in testis tissues of the high-dose group were significantly increased(P<0. 05). CONCLUSION: Procymidone can cause damage to the structure and function of testes, reduce sperm quality, and increase the expression of certain pro-apoptotic genes in adolescent male mice.

Microglial cell hyper-ramification and neuronal dendritic spine loss in the hippocampus and medial prefrontal cortex in a mouse model of PTSD.

Few animal models exist that successfully reproduce several core associative and non-associative behaviours relevant to post-traumatic stress disorder (PTSD), such as long-lasting fear reactions, hyperarousal, and subtle attentional and cognitive dysfunction. As such, these models may lack the face validity required to adequately model pathophysiological features of PTSD such as CNS grey matter loss and neuroinflammation. Here we aimed to investigate in a mouse model of PTSD whether contextual fear conditioning associated with a relatively high intensity footshock exposure induces loss of neuronal dendritic spines in various corticolimbic brain regions, as their regression may help explain grey matter reductions in PTSD patients. Further, we aimed to observe whether these changes were accompanied by alterations in microglial cell number and morphology, and increased expression of complement factors implicated in the mediation of microglial cell-mediated engulfment of dendritic spines. Adult male C57Bl6J mice were exposed to a single electric footshock and subsequently underwent phenotyping of various PTSD-relevant behaviours in the short (day 2-4) and longer-term (day 29-31). 32 days post-exposure the brains of these animals were subjected to Golgi staining of dendritic spines, microglial cell Iba-1 immunohistochemistry and immunofluorescent staining of the complement factors C1q and C4. Shock exposure promoted a lasting contextual fear response, decreased locomotor activity, exaggerated acoustic startle responses indicative of hyperarousal, and a short-term facilitation of sensorimotor gating function. The shock triggered loss of dendritic spines on pyramidal neurons was accompanied by increased microglial cell number and complexity in the medial prefrontal cortex and dorsal hippocampus, but not in the amygdala. Shock also increased expression of C1q in the pyramidal layer of the CA1 region of the hippocampus but not in other brain regions. The present study further elaborates on the face and construct validity of a mouse model of PTSD and provides a good foundation to explore potential molecular interactions between microglia and dendritic spines.

No Difference Between Age-Matched Male and Female C57BL/6J Mice in Photopic and Scotopic Electroretinogram a- and b-Wave Amplitudes or in Peak Diurnal Outer Segment Phagocytosis by the Retinal Pigment Epithelium.

Mice provide informative models of enormous utility for eye research. Sex as biological variable must be considered when conducting studies exploring mouse models. To determine if sex confounds neural retina or retinal pigment epithelium (RPE) activity in wild-type C57BL/6J mice, we compared male and female mice with respect to retinal light response and RPE phagocytosis. We tested 2-month-old mice at peak fertility and 12-month-old mice past fertility. Retinal function was assessed by quantifying a- and b-wave amplitudes of photopic and scotopic electroretinograms (ERGs). These experiments did not reveal differences between male and female mice at either age. As expected from earlier studies, 12-month-old mice showed reduced light responses compared to 2-month-old mice, but age-related decline was identical for male and female mice. RPE functionality was assessed by quantifying RPE phagosome content 1 h after light onset in mice 2 months of age, an age of maturity of the process of outer segment turnover that includes RPE phagocytosis. These experiments did not reveal differences in RPE phagocytosis between male and female mice. Altogether, male and female C57BL/6J mice do not differ in retinal light response and peak RPE phagocytic activity. Retinal activity is impaired with age to the same extent in male and female mice. Our results justify testing mixed-sex mouse cohorts in studies on outer segment renewal and RPE phagocytosis and illustrate the importance of careful consideration of cohort age.

Sweeteners modulate bioactivity of endothelial progenitor cells but not induce detrimental effects both on inflammation and behavioural changes.

This study sought to determine the possible detrimental effects of several low- or non-caloric sweeteners on endothelial progenitor cells (EPCs), inflammation and behavioural changes in mice. C57BL/6 male mice received low and high dose of natural and artificial sweeteners for 4 weeks. EPCs, physical and biochemical variables, inflammation and behavioural changes were evaluated. A significant reduction of about 25% of EPCs was found when mice received a moderate amount of all sweeteners (p < .05). This reduction was more strongly significant when a double dose of glucose, aspartame, rebaudioside A and cyclamate (p < .005) in comparison to fructose and sucrose (p < .05) was administered. During inflammation carrageenan-induced, all sweeteners produced a significant increase of EPCs compared to the control group (p < .05). Consumption of glucose and sugar substitutes affect mouse EPC number according to the absence or presence of an inflammatory status, but does not induce detrimental effects on inflammation and behavioural changes.

NMDA receptor blockade ameliorates abnormalities of spike firing of subthalamic nucleus neurons in a parkinsonian nonhuman primate.

N-methyl-D-aspartate receptors (NMDARs) are ion channels comprising tetrameric assemblies of GluN1 and GluN2 receptor subunits that mediate excitatory neurotransmission in the central nervous system. Of the four different GluN2 subunits, the GluN2D subunit-containing NMDARs have been suggested as a target for antiparkinsonian therapy because of their expression pattern in some of the basal ganglia nuclei that show abnormal firing patterns in the parkinsonian state, specifically the subthalamic nucleus (STN). In this study, we demonstrate that blockade of NMDARs altered spike firing in the STN in a male nonhuman primate that had been rendered parkinsonian by treatment with the neurotoxin 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine. In accompanying experiments in male rodents, we found that GluN2D-NMDAR expression in the STN was reduced in acutely or chronically dopamine-depleted animals. Taken together, our data suggest that blockade of NMDARs in the STN may be a viable antiparkinsonian strategy, but that the ultimate success of this approach may be complicated by parkinsonism-associated changes in NMDAR expression in the STN.