Relative Testis Research Articles

Eugenol alleviates acrylamide-induced rat testicular toxicity by modulating AMPK/p-AKT/mTOR signaling pathway and blood-testis barrier remodeling.

This study aimed to investigate the effects of eugenol treatment on reproductive parameters in acrylamide (ACR)-intoxicated rats. The study evaluated alterations in relative testes and epididymides weights, sperm quality, serum hormonal status, seminal plasma amino acids, testicular cell energy and phospholipids content, oxidative and nitrosative stress parameters, adenosine monophosphate-activated protein kinase/ phosphoinositide 3-kinase/phosphor-protein kinase B/mammalian target of rapamycin (AMPK/PI3K/p-AKT/mTOR) signaling pathway, blood-testis barrier (BTB) remodeling markers, testicular autophagy and apoptotic markers, as well as histopathological alterations in testicular tissues. The results revealed that eugenol treatment demonstrated a significant improvement in sperm quality parameters, with increased sperm cell concentration, progressive motility live sperm, and a reduction in abnormal sperm, compared to the ACR-intoxicated group. Furthermore, eugenol administration increased the levels of seminal plasma amino acids in a dose-dependent manner. In addition, eugenol treatment dose-dependently improved testicular oxidative/nitrosative stress biomarkers by increasing oxidized and reduced glutathione levels and reducing malondialdehyde and nitric oxide contents as compared to ACRgroup. However, eugenol treatment at a high dose restored the expression of AMPK, PI3K, and mTOR genes, to levels comparable to the control group, while significantly increasing p-AKT content compared to the ACRgroup. In conclusion, the obtained findings suggest the potential of eugenol as a therapeutic agent in mitigating ACR-induced detrimental effects on the male reproductive system via amelioration of ROS-mediated autophagy, apoptosis, AMPK/p-AKT/mTOR signaling pathways and BTB remodeling.

Antifertility effects of EP-1 (quinestrol and levonorgestrel) on Pacific rats (Rattus exulans).

Pest rodents pose a serious threat to island biodiversity. Fertility control could be an alternative approach to control the impact of rodents on these islands. In this study, we examined the antifertility effects of EP-1 baits containing quinestrol (E) and levonorgestrel (P) using a dose of 50 ppm E and P at three different ratios (E:P ratio = 1:2, 1:1, and 2:1) on Pacific rats (Rattus exulans) in the Xisha Islands, Hainan, China. Compared to the control group, all animals in EP-1 treatment groups showed significantly decreased food intake and body weight. In treated males, there were obvious abnormalities in testis structure and a significant decrease of relative seminal vesicle weight, but no significant effect on relative uterine and ovarian weights (gkg-1 body weight), or ovarian structure in females. Adding 8% sucrose to the original 50-ppm baits (E:P ratio = 1:1) significantly increased bait palatability for males and females. This dose induced uterine edema and abnormalities of ovarian structure in females but had no significant negative effect on the relative testis, epididymis, and seminal vesicle weights (gkg-1 body weight) or sperm density in males. In summary, 50-ppm EP-1 (1:1) baits have the potential to disrupt the fertility of females, and 8% sucrose addition to the EP-1 baits (E:P ratio = 1:1) could improve bait palatability. This dose disrupted the testis structure in males. Future studies are needed to improve bait acceptance and assess the antifertility effects of EP-1 (1:1) on Pacific rats in captive breeding trials and under field conditions.

Alterations in gonadotropin, prolactin, androgen and estrogen receptor and steroidogenesis-associated gene expression in gander testes in relation to the annual period

Physiological mechanisms of seasonal changes in testicular function in birds are not fully elucidated. The balance between androgens and estrogens and testis sensitivity for gonadotropin and gonadal steroids are still unclear. The aim of the study was to examine: (1) the changes in circulating and intra-testicular steroid hormone levels and their relationship; (2) the mRNA expression of testicular gonadotropin, prolactin (PRL), progesterone (P4), androgen, and estrogen receptors, and (3) key steroidogenesis processes-related genes with immunofluorescent localization of aromatase in gander testes during the annual period. Testes from ganders (n = 25) in the first reproduction season were obtained at five breeding stages, i.e., prebreeding (PrB), peak of reproduction (PR), postbreeding (PoB), nonbreeding (NB), and onset of reproduction (OR). Males were kept under breeding conditions. It was found that plasma P4 levels decreased at the PoB and NB stages, whereas intra-testicular P4 was the highest in the NB stage. Intra-testicular estradiol (E2) levels were higher at the PoB and NB stages than the other stages, whereas testosterone (T) levels showed a nearly opposite pattern. The plasma estradiol–to–testosterone ratios were higher at the PrB, PoB and NB stages compared to other stages. The transcript abundances for luteinizing hormone receptor (LHR), PRL receptor (PRLR), estrogen receptor alpha (ERα), and estrogen receptor beta (ERβ) also change in testicular tissue during the annual period. Moreover, StAR mRNA expression was upregulated at the PoB and NB stages, and CYP11A1 transcript level was the highest at the PoB stage. Stage-dependent changes in the CYP19A1 mRNA and aromatase protein levels with higher abundances of transcript at PoB and NB stages and protein at the NB stage were observed. Localization and immunofluorescent signal intensity for aromatase also differed in relation to the examined stages. It may be suggested that differential E2 levels, as well as aromatase expression and localization across annual stages are responsible for the seasonal activation/inactivation stages of testis spermatogenesis in domestic ganders. These data strongly suggest a role of aromatase in the control of gander steroidogenesis as changes in this enzyme level are associated with alternation in gonadal steroid hormones. In addition, joint action with others hormones, like PRL and LH, seems to be important in the final effect of seasonal reproduction potential.

Comparison of the spermatogenic process in three different mice strains: Swiss, Balb/C and C57BL/6

Many studies have been trying to establish standard protocols for animal experimentation, especially for animal species or strains, to master research variables with high precision. The main mouse strains used in the field of the biology of reproduction are Swiss, Balb/c, and C57BL/6. Since some of the strains show reproduction limitations, such as the size of the litter, the present study aimed to compare their spermatogenic processes to verify differences regarding the testicular parenchyma and germ cell populations, which could explain low offspring production. In addition, the present study provides additional information concerning the testicular parenchyma of such strains, which consequently would help researchers to choose the most suitable strain for reproductive studies. Six adult male mice were used for each of the strains. After euthanasia, the testes were weighed, fixated with Karnovsky fixative, embedded in methacrylate, sectioned, and stained with toluidine blue/sodium borate 1%. Morphometrical analyses from the testicular parenchyma (seminiferous tubules and interstitium) were made using the software ImageJ. Germ and Sertoli cells populations were counted in seminiferous tubules cross-sections at stage I of the seminiferous epithelium cycle. The lowest body and testicular weights were observed in C57BL/6 animals, followed by Balb/c and Swiss, however, the relative testes, parenchyma, and albuginea weights were significantly lower only in C57BL/6. Despite the seminiferous tubules and seminiferous epithelium proportions were lower in Swiss animals, their relative amount related to the body weight was the same among strains. The total number of germ cells was higher in Swiss animals, reflecting higher spermatogenic yield and daily sperm production. Due to the lower relative number of Sertoli cells, the Swiss animals showed the highest Sertoli cell index and support capacity. On the other hand, the lowest pathological indexes regarding the germ cells were observed in Balb/c animals, followed by Swiss and C57BL/6. In the interstitium, the proportion of blood vessels was lower in Swiss mice, while the lymphatic cell proportion was lower in C57BL/6 animals. Moreover, the highest proportions of Leydig cells and macrophages were noticed in Swiss mice, which may indicate increased testosterone levels. Altogether, such observations must be taken into account when choosing any of the studied strains for reproduction studies.

Growth of Japanese Quail Testes in Relation to Age: Morphological and Immunohistochemical Observation

Objective: The purpose of this research was to observe the age-related growth and histomorphological changes in Japanese quail testes from post-hatching to sexual maturity as well as spermatogenesis.Materials and Methods: After collection, the testes weight, length, width, and index analysis were performed, and histomorphological, histological and immunohistochemical observations were conducted using hematoxylin-eosin, PAS-hematoxylin, and anti-Hsc70t staining, respectively at different ages.Results: The weight of the testes increased gradually with age and reached a peak at 70 days. The length and width of the testes were maximal at 70 days. The testis index was positively correlated with age and body weight (BW) toward sexual maturity. Histologically, at 15 days of age, the seminiferous tubules (STs) remained in immature state with undifferentiated spermatogenic cells of only one to two layers of epithelial cells. At 28 days, the spermatogenic cells were differentiated from spermatogonia to spermatocytes. At 42 days, remarkable enlargement of STs with a series of spermatogenic cell development up to the round spermatids and Leydig cells in the interstitial region. Finally, at 70 days, extremely enlarged STs containing all stages of spermatogenic cells. The diameter and height of STs were maximal at 70 days than that of 42 days of age. A strong Hsc 70t immunoreaction was found in the round to elongated spermatids/spermatozoa near to the lumen of STs, clearly indicating well-characterized spermatogenesis in quail testis at 70 days of age.Conclusion: The findings may contribute to our understanding of quail’s spermatology and provide basic knowledge for reproductive toxicology, physiology and pathology studies.

Role of pyroglutamylated RFamide peptide43 in germ cell dynamics in mice testes in relation to energy metabolism

QRFP is a neuropeptide that regulates glucose homeostasis and increases insulin sensitivity in tissues. We have previously shown that QRFP and its receptor (GPR103) are predominantly expressed in germ cells and Sertoli cells, respectively, in mice testes. In the present study, we report that QRFP caused an increase in PCNA and a decrease in p27Kip1 expressions in the testis under both in vivo and ex vivo conditions. Besides, via an in vivo study, cell cycle analysis by FACS showed an increase in 2C cells and a decrease in 1C cells. QRFP also induced expression of GDNF and phosphorylation of Akt and ERK-1/2. Together these results suggest that QRFP has a proliferative effect on germ cells in mice testes, since it caused a proportional increase in the mitotic activity and the number of spermatogonial cells. Further, observations of increased expressions of STAT-3 and Neurog3 in treated mice suggest that QRFP treatment regulates priming of undifferentiated spermatogonia to undergo differentiation, while a decrease in c-Kit expression indicate that spermatogonia at this time point are in an undifferentiated state. In addition, QRFP administration also caused an increase in intratesticular levels of glucose and lactate, and in LDH activity accompanied by increased expressions of GLUT-3 and LDH-C in the testis. Also, the phosphorylation of IR-β and expressions of p-Akt and p-mTOR were increased under ex vivo conditions in testicular tissue. In conclusion, our findings suggest that QRFP treatment caused proliferation of germ cells independently from the hypothalamic-pituitary axis via regulation of testicular energy metabolism.

Effect of whey protein supplementation on sperm quality and fertility in male mice

Protein supplements are a billion-dollar industry and the intake of these supplements is increasing, especially among young men. However, little is known about whether consumption of these products affects the reproductive health. The aim of this study was to assess the effect of whey protein supplementation on the sperm quality and reproductive health of male mice. A total of 48 male NMRI mice were fed with either plain tap water or a high dose of whey protein (Whey100, BodyLab) supplemented in the drinking water for 3 months. Mice was individually housed with two female mice for five days and reproductive parameters were assessed. DNA fragmentation index (DFI) was assessed at 0 h and 4 h of in vitro incubation using a sperm DNA integrity test (SDI®-test). No significant differences were detected between the groups in the epididymal sperm count, sperm motility, DFI, oxidation-reduction potential (ORP), serum testosterone, body and seminal vesicles weights, relative testis and epididymal weights, testicular morphology, number of impregnated females, or litter size. No correlation was found between ORP and DFI. These results suggest that the highest recommended human dose of whey protein supplementation do not significantly impair the sperm quality and fertility in male mice.

Di-(2-Ethylhexyl) Phthalate Increases Obesity-Induced Damage to the Male Reproductive System in Mice.

Objective This study evaluated the effects of di-(2-ethylhexyl) phthalate (DEHP) and obesity on male reproductive organ function in male mice and the potential mechanism of male secondary hypogonadism (SH) in such mice. Methods 140 mice were assigned to six groups for 12 weeks: normal, DEHP, DIO, DIO + DEHP low, DIO + DEHP middle, and DIO + DEHP high. The effects of DEHP and obesity upon the reproductive organs were determined by measuring sperm count and motility, relative testis and epididymis weight, hormone level, and pathological changes. Oxidative stress was evaluated by determining malondialdehyde, T-AOC, SOD, GSH, H2O2, CAT, and GSH-PX in testicular tissues. Nrf2 and Keap1 protein were measured by Western blotting. Results DEHP and obesity reduced sperm count and motility, relative testis and epididymis weight, and testosterone level but increased the levels of MDA, H2O2, leptin, and estradiol. Pathological injury was observed in the testicular Leydig cells. Moreover, the activity of CAT, SOD, and GSH-Px enzymes was inhibited. Nrf2 protein expression was reduced but that of Keap1 was increased. Conclusions DEHP and obesity jointly caused damage to male productive function. Oxidative stress in testicular tissue, and a high level of leptin, may provide some evidence to clarify the mechanisms of male SH with DEHP and obesity.

Effect of Acrylamide Ingestion on Reproductive Organs of Adult Male Wistar Rats

Introduction: Acrylamide, an industrial toxic chemical, formed naturally in starchy foods, cooked at high temperature. Acrylamide is known to cause reproductive toxicity in male rats and extent of its effect with respect to sperm and histopathological parameters is not well studied.Aim: To evaluate the influence of acrylamide on male reproductive structural and functional alterations. Materials and Methods: We examined the toxic potential of acrylamide doses, including 0 (distilled water), 6.25, 25 mg/kg body weight/day, in 18 adult male Wistar rats administered by oral gavage for 21 days. Body weight was recorded daily, and the animals were sacrificed at the end of treatment. The relative testis and epididymis wet weights were measured. Sperm count, motility, and morphology were assessed from the epididymis sperm reserve. The testis and epididymis were examined for histological abnormalities. One-way ANOVA was used to test the significant difference in the quantitative responses, followed by Tukey HSD pairwise comparison test.Results: The acrylamide decreased the body weight (p<0.001) and epididymis weight (p<0.05) significantly. The epididymal sperm reserve in the high dose group were observed with significant changes in count, motility and morphology. Histologically, the high dose exposed epididymis, showed sloughing and apoptosis of germ cells inducing reduced sperm capacitance and vacuolar degeneration of basal epithelium. The high dose treated testis showed atrophy with reduced luminal diameter.C onclusion: We observed significant reproductive toxicity in male Wistar rats after the acrylamide ingestion, which is similar to the dose of exposure that can be taken in, by that population, who regularly consume food items having acrylamide in it. Hence, our findings strengthened the concern about male reproductive toxicity of acrylamide exposure and demanding the awareness on the same.

Effect of Supplementation Different Levels of Vitamin E and Pumpkin Seed Oil to the Diet on Productive, Physiological and Reproductive Performance of Japanese Quail

The principal goal of this study was to evaluate whether dietary vitamin E and pumpkin seed oil would affect the productive, physiological and reproductive performance of Japanese quail by using 120 birds at 22 weeks of age. The birds were randomly distribution into five dietary groups 24 birds each group contain three replicated pens, as follow: First group: kept on basal diet without any addition as control group, second and third groups were fed the basal diet supplemented with 150 and 200 mg/ kg vitamin E / kg of diet, fourth and fifth groups were fed the basal diet supplemented with 15 and 30 ml/kg pumpkin seed oil /kg of diet respectively. The results showed a significant improvement in egg production (H.D%), egg number, egg weight and egg mass produced for the vitamin E (200mg/ kg of diet) compared with the other groups. Additionally, the results showed that vitamin E (200mg/ kg of diet) significantly increased gonads relative weight , testes development, egg characterizes and serum testosterone, estrogen, FSH and LH hormones compared with other groups. Also , the birds were fed on 15 and 30 ml seed pumpkin oil/ kg of diet were significantly increased in the most parameter compared with control group. It can be concluded that the addition of vitamin E (200 mg/kg of diet) and pumpkin seed oil (30ml of diet), had positive effects on gonads, testicular histology, egg production and serum testosterone, estrogen, FSH and LH hormones concentration.

Sperm Supply from the Testes to the Seminal Vesicle over Consecutive Matings in the Sweetpotato Weevil, &amp;lt;i&amp;gt;Cylas formicarius&amp;lt;/i&amp;gt; (F&amp;lt;sub&amp;gt;ABRICIUS&amp;lt;/sub&amp;gt;) (Coleoptera: Curculionidae)

The sweetpotato weevil, Cylas formicarius, stores free sperm in both the testes and the seminal vesicle, even though the primary function of the testes is sperm production. Here, it was investigated sperm storage in the testes in relation to mating frequency. In particular, it was examined the effect of the positional relationship between the testes and seminal vesicle, on sperm storage by counting the number of sperm in those organs. After mating, not only were the number of free sperm in the seminal vesicle reduced, but also was the number in the testes, suggesting that free sperm stored in the testes moved into the seminal vesicle during or immediately after mating. Since this weevil seems to not regulate the number of sperm in the seminal vesicle for ejaculation, the sperm supply system of the testes may contribute ejaculate to support consecutive, multiple matings by this weevil.

Expression of Melatonin Receptor Subtype Genes and its Impact on Reproductive Traits in Japanese Quail in Different Lighting Systems

Melatonin receptors are G-protein coupled receptors which mediate the action of melatonin hormone. In this study, we investigated the effects of two different lighting systems, 23 h L: 1 h D (group I) and 12 h L: 12 h D (group II), on reproductive traits in Japanese Quail ( Coturnix coturnix japonica). As well as the expression pattern of three melatonin receptor subtypes, mRNA in ovaries and testes were analysed using quantitative real time PCR. The results revealed the expression of all three subtypes of melatonin receptors (MNTR1A, MNTR1B and MNTR1C) in ovaries and MNTR1B, MNTR1C in testes in both groups. Further, the expression of melatonin receptors was significantly higher in group II relative to group I. The fold change level of MNTR1C was 6.7 in ovaries and 3.1 in testes in short day light. Altered expression pattern of these genes associated with changes in Japanese Quail reproductive traits, while, Japanese Quail exposed to long day light started egg laying earlier than those in short day light. Egg weight and egg percentage increased significantly in group I compared to group II. The average of relative ovary and testis weight at six weeks of age were declined by 1.72 and 1.64 g, respectively, in group II. It was concluded that, different lighting system induced different expression levels of melatonin receptor genes accompanied with changes in reproductive traits in both sex of Japanese Quail.

Toxoplasma gondii decreases the reproductive fitness in mice.

Toxoplasma gondii is a common protozoan parasite that infects warm-blooded animals throughout the world, including mice and humans. During infection, both, the parasite and the host, utilize various mechanisms to maximize their own reproductive success. Mice and humans are both the intermediate hosts for Toxoplasma gondii, which forms specialized vacuoles containing reproductive cysts in the formers’ tissue. As half of the human population is infected, developing a disease called toxoplasmosis, along with an ever-growing number of couples suffering with idiopathic infertility, it is therefore surprising that there is a lack of research on how Toxoplasma gondii can alter reproductive parameters. In this study, a detailed histometric screening of the testicular function along with the levels of the pituitary luteinizing hormone (LH) were analysed in infected mice. Data on relative testis and epididymis weight, and sperm count were also collected. Based on the results obtained, the level of LH in the urine of Toxoplasma gondii infected mice was lower compared to the control. In direct correlation with the hormone level, testicular function and sperm production was also significantly lower in Toxoplasma gondii positive group using sperm count and histometric analysis as a marker. Not only were the number of leptotene primary spermatocytes and spermatids lowered, but the number of Sertoli cells and the tubule diameter were elevated. In parallel, a pilot epigenetic study on global testicular methylation, and specific methylation of Crem, Creb1 and Hspa1genes essential for successfully ongoing spermatogenesis was performed. Global methylation was elevated in Toxoplasma infected mice, and differences in the DNA methylation of selected genes were detected between the Toxoplasma positive and control group. These findings demonstrate a direct relation between Toxoplasma gondii infection and the decrease of male reproductive fitness in mice, which may contribute to an increase of idiopathic infertility in humans.

Desenvolvimento corporal e testicular em machos de codornas de corte e de postura de 25 a 360 dias

Codornas do tipo carne e tipo ovos foram analisadas para determinar o desenvolvimento reprodutivo, a puberdade e o início da senilidade. Para tal, 288 codornas (144 codornas de corte e 144 de postura) foram acompanhadas desde a eclosão até os 360 dias de idade. As aves foram distribuídas por idade em 18 grupos, sendo 8 codornas/grupo/tipo de codorna. Após 35 dias as codornas foram mantidas em condições de fotoperíodo de dias longos (17luz: 7escuro). O peso vivo e os valores morfométricos e histológicos testiculares foram determinados em cada período. Os dados obtidos foram analisados para determinar a curva de crescimento e o comportamento dos parâmetros analisados. O modelo que mais se adequou aos dados foi o modelo não linear de Gompertz (Y=A exp [-B e (-kt)]). O peso vivo e as características testiculares macro e microscópicas apresentaram comportamento alométrico entre si, sendo que, aproximadamente aos 60 dias os machos apresentaram-se sexualmente desenvolvidos, e estabilizaram o peso corporal por volta dos 100 dias. O testículo direito é mais cranial que o esquerdo e diferem em relação a comprimento e largura, porém não foi observada diferenças (P&gt;0,05) para peso testicular. As codornas de corte apresentaram peso corporal e peso testicular maiores que as codornas de postura, porém as codornas de postura apresentaram peso relativo testicular maior. Durante todo o período analisado os machos puderam ser considerados sexualmente aptos. Os reprodutores apresentaram características sexuais ativas até os 360 dias de idade, representadas pelo tamanho testicular e pela atividade celular nos túbulos seminíferos.

Selective Predation of Tawny Owls (Strix aluco) on Yellow-Necked Mice (Apodemus flavicollis) and Bank Voles (Myodes glareolus)

Differential predation on certain classes of individuals within prey populations might make owls strong selective agents on their prey. We investigated selective predation of tawny owls (Strix aluco) on yellow-necked mice (Apodemus flavicollis, A.f.) and bank voles (Myodes glareolus, M.g.) for two years by comparing prey from owl nests with live-trapped individuals. The owls killed significantly more male M.g. (73%) than females, but not more than expected from traps (57%). For A.f., owls selected adults in favour of subadults, and for adults, individuals with longer femurs. Adult males of A.f. killed by owls had significantly heavier testes in relation their size than the trapped males. Prey selection did not correlate with size-adjusted body or spleen mass. Owl-killed A.f. had higher prevalences of the intestinal helminth Heligmosomoides sp. than trapped individuals, but hosted similar numbers of parasite species. Differential predation of tawny owls on yellow-necked mice and bank voles seems to reflect higher exposure to predator encounters of prime individuals rather than selection for substandard individuals.

Allometric Growth of Testes in Relation to Age, Body Weight and Selected Blood Parameters in Male Japanese Quail (Coturnix japonica).

The Japanese quail is a very valuable animal model for research in a variety of biological disciplines. The purpose of this study was to characterize and interrelate age-dependent testicular parameters with various blood constituents: blood glucose, plasma proteins and packed cell volume that are developing concurrently in the growing bird. Another objective of the study was to identify selective physioanatomical markers for predicting the testicular growth and the onset of sexual maturity. Male Japanese quail hatchlings were raised in temperature controlled brooders for up to 3 weeks of age under a constant light and then shifted to hanging cages in an air conditioned room set at ~73° F under a 14L: 10D lighting system and ad libitum access to feed and water. Starting d8, a group of 8-10 birds of uniform size and weight were selected randomly at 4-day intervals up to d52 of age for the project. The birds were weighed and blood sampled using the brachial vein and Blood Glucose (BGL), Total Plasma Proteins (PP) and Packed Cell Volume (PCV) levels were measured prior to euthanization. The testes were removed and measured for weight, length, width and Volume (VOL). All the testicular measurements were then correlated with age and body weight. The left testes were larger than the right testes and their differences were evident at d36 of age. Testicular measurements also reflected two distinct growth surges at d28, d32 and d36 of age. Combined Testes Weight (CTW) and Combined Testes Volume (CTV) revealed a strong positive correlation with PCV and PP and a negative correlation with Blood Glucose Level (BGL). Accordingly, these measurements could serve as reliable markers of growth rate and sexual maturation in male Japanese quail.

Effects of Nobiletin on PhIP-Induced Prostate and Colon Carcinogenesis in F344 Rats

The current study was designed to investigate the effects of nobiletin (5,6,7,8,3′,4′-hexamethoxy flavone) on 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP)-induced prostate and colon carcinogenesis. PhIP was administered to 6-wk-old F344 male rats intragastrically (100 mg/kg) twice a wk for 10 wk. The animals were given 0.05% nobiletin or the basal diet for 50 wk. At the end of the experiment, serum testosterone, estrogen, and leptin did not differ between the 2 groups. The body weights of nobiletin-treated rats were significantly higher than controls (P < 0.05), and feeding of nobiletin significantly reduced the relative prostate (P < 0.05) and testes (P < 0.05) weights as well as the Ki67 labeling index in the normal epithelium in the ventral prostate (P < 0.01). The incidence and multiplicity of adenocarcinomas in nobiletin-treated ventral prostate were 50% and 36%, respectively, of controls, but the differences were not statistically significant. However, nobiletin did significantly reduce the total number of colonic aberrant crypt foci (ACF) compared to the control value (P < 0.05). Nobiletin, therefore, may have potential for chemoprevention of early changes associated with carcinogenesis in both the prostate and colon.

Intra-Abdominal Testis: Histological Alterations and Significance of Biopsy

Intra-abdominal testes represent only 5% of undescended testes. Review of the literature reveals that few data exist on the histological analysis of intra-abdominal testes. We studied histological alterations in intra-abdominal testes in relation to patient age at orchiopexy. A total of 57 boys underwent laparoscopy for impalpable undescended testes between October 2002 and June 2005. Testicular biopsies were taken from intra-abdominal testes, fixed in 3% glutaraldehyde, embedded in Epon, sectioned at 1 micron thickness and stained with toluidine blue. Histomorphometric analysis was performed by light microscopy. Effect of age at operation on histological evaluation of abdominal testes was also studied. Testicular biopsies from 29 patients with intra-abdominal testes showed the histological alterations of decreased mean diameter of seminiferous tubules, germinal cell depletion (55%) and presence of microliths (6.9%). As age at orchiopexy increases, deviation from the norm is more evident and absence of germ cells on biopsy becomes more pronounced, reaching a rate of 93% after age 3 years. Further studies on orchiopexy with or without biopsy in the first few months of life would likely improve our understanding and treatment of cryptorchidism.

Larger testes are associated with a higher level of polyandry, but a smaller ejaculate volume, across bushcricket species (Tettigoniidae)

While early models of ejaculate allocation predicted that both relative testes and ejaculate size should increase with sperm competition intensity across species, recent models predict that ejaculate size may actually decrease as testes size and sperm competition intensity increase, owing to the confounding effect of potential male mating rate. A recent study demonstrated that ejaculate volume decreased in relation to increased polyandry across bushcricket species, but testes mass was not measured. Here, we recorded testis mass for 21 bushcricket species, while ejaculate (ampulla) mass, nuptial gift mass, sperm number and polyandry data were largely obtained from the literature. Using phylogenetic-comparative analyses, we found that testis mass increased with the degree of polyandry, but decreased with increasing ejaculate mass. We found no significant relationship between testis mass and either sperm number or nuptial gift mass. While these results are consistent with recent models of ejaculate allocation, they could alternatively be driven by substances in the ejaculate that affect the degree of polyandry and/or by a trade-off between resources spent on testes mass versus non-sperm components of the ejaculate.

Divergent expression of 11β-hydroxysteroid dehydrogenase and 11β-hydroxylase genes between male morphs in the central nervous system, sonic muscle and testis of a vocal fish

The vocalizing midshipman fish, Porichthys notatus, has two male morphs that exhibit alternative mating tactics. Only territorial males acoustically court females with long duration (minutes to >1 h) calls, whereas sneaker males attempt to steal fertilizations. During the breeding season, morph-specific tactics are paralleled by a divergence in relative testis and vocal muscle size, plasma levels of the androgen 11-ketotestosterone (11KT) and the glucocorticoid cortisol, and mRNA expression levels in the central nervous system (CNS) of the steroid-synthesizing enzyme aromatase (estrogen synthase). Here, we tested the hypothesis that the midshipman’s two male morphs would further differ in the CNS, as well as in the testis and vocal muscle, in mRNA abundance for the enzymes 11β-hydroxylase (11βH) and 11β-hydroxysteroid dehydrogenase (11βHSD) that directly regulate both 11KT and cortisol synthesis. Quantitative real-time PCR demonstrated male morph-specific profiles for both enzymes. Territorial males had higher 11βH and 11βHSD mRNA levels in testis and vocal muscle. By contrast, sneaker males had the higher CNS expression, especially for 11βHSD, in the region containing an expansive vocal pacemaker circuit that directly determines the temporal attributes of natural calls. We propose for territorial males that higher enzyme expression in testis underlies its greater plasma 11KT levels, which in vocal muscle provides both gluconeogenic and androgenic support for its long duration calling. We further propose for sneaker males that higher enzyme expression in the vocal CNS contributes to known cortisol-specific effects on its vocal physiology.