Testis Testosterone Concentrations Research Articles

Beneficial effects of roots of Argyreia nervosa (Brum.f.) Bojer on testosterone biosynthesis in testis and spermatogenesis in Wistar rats

Ethnopharmacological relevanceRoots of Argyreia nervosa (Burm.f.) Bojer is used traditionally as an aphrodisiac and mentioned in the indigenous system of medicine as spermatogenic. The roots of the plant are also used as bitter, tonic, and alternative. Aim of the studyTo study the effect of n-butanol fraction (BTF) and ethyl acetate fraction (ETF) of methanol extract prepared from the roots of Argyreia nervosa and scopoletin isolated from ETF on testosterone biosynthesis in testis and spermatogenesis using rats. Materials and methodsThe effect of BTF, ETF, and scopoletin on the testosterone biosynthesis was evaluated by determining the alteration in expression of mRNA corresponding to steroidogenic enzymes and concentration of testosterone using TM-3 cell line. The ability of BTF and ETF in altering the level of testicular cholesterol and testosterone along with mRNA expression corresponding to 3β-Hydroxy-Δ5-steroid dehydrogenase (3β-HSD) and Acute Steroid Regulatory Protein (StAR) was evaluated using rats as experimental animals. The sperm concentration in the seminal fluid was determined, and histological studies of testicular tissues were also carried out. ResultsTest solutions containing BTF, ETF, and scopoletin showed a dose-dependent and statistically significant increase in the testosterone content when incubated with TM-3 cells. The test solutions also increased the fold expression of mRNA corresponding to StAR and 3β-HSD enzymes from TM-3 cells. BTF and ETF elevated testicular testosterone levels by 3.57 and 3.84-fold as compared to control animals, while the fractions showed 9.04 and 10.41-fold alteration in expression of mRNA corresponding to StAR, respectively. BTF and ETF altered the expression of mRNA corresponding to 3β-HSD by 13.43 and 15.04-fold in testicular tissues; moreover, they elevated the activity of 3β-HSD by 7.11 and 7.73 fold, respectively. The animals treated with BTF and ETF showed increased sperm concentration. Histological observations showed that the lumen of seminiferous tubules was densely populated with spermatozoa and Leydig cells were intensely stained. Extract prepared from fruits of Tribulus terrestris Linn and testosterone served as positive controls. ConclusionBTF, ETF, and scopoletin could promote testosterone biosynthesis by elevating mRNA expression corresponding to StAR, 3β-HSD, and by increasing 3β-HSD activity in the testicular tissues. Elevated testosterone concentration in testis promoted spermatogenesis. The studies provided the probable mechanism through which the roots of A. nervosa act as spermatogenic.

The Administration of Epididymis Extract Increased the Testosterone Concentration without Affects the Dihydrotestosterone Concentration in Local Male Goat

This study was aimed to determine the effect of epididymis extract (EE) on the testosterone and dihydrotestosterone (DHT) level of local male goat. An experimental study was performed using a completely randomized design (CRD) pattern of one-way analysis of variance (ANOVA). 15 local male goats aged 1.5 years with body weight 14-16 kg were used in this study. The K0 group as a control group, injected with only 1 ml physiological saline, while each KP1, KP2, KP3, and KP4 groups treated with multilevel EE dose, ie 1, 2, 3, and 4 ml / goat for 13 consecutive days. At the end of treatment (day 14th), testes, epididymis (caput, corpus, and cauda) and ductus deferens samples were taken through the close-castration method for examining the testosterone and DHT concentration by using enzyme-linked immunosorbent assay (ELISA) technique. Data gathered were later analyzed using ANOVA followed by Tukey’s HSD in SPSS 16.0 for Windows. The result showed that the average concentration of testosterone on K0, KP1, KP2, KP3, and KP 4 in testis respectively were 10.00±2.64 ng/ml; 7.66±2.51 ng/ml; 10.00±6.55 ng/ml; 0.66±0.57 ng/ml; 11.66±7.37 ng/ml; caput epididymis; 5.00±1.73 ng/ml; 2.33±1.52 ng/ml; 5.00±2.64 ng/ml; 1.33±0.57 ng/ml; 5.66±1.15 ng/ml; corpus epididymis; 1.33±0.57 ng/ml; 0.66±0.57 ng/ml; 4.00±2.64 ng/ml; 0.66±0.57 ng/ml; 4.33±2.30 ng/ml; cauda epididymis: 1.00±0.00 ng/ml; 0.66±0.57 ng/ml; 1.66±0.57 ng/ml; 1.00 ± 0.00 ng/ml; 2.00±1.73 ng/ml; ductus deferens: 3.66±2.51 ng/ml; 0.66±0.57 ng/ml; 3.00±1.00 ng/ml; 1.00±0.00 ng/ml and 3.66±1.15 ng/ml. While the average concentration of DHT on K0, KP1, KP2, KP3, and KP 4 in testis respectively; 10.00±2.64 ng/ml; 7.66±2.51 ng/ml; 10.00±6.55 ng/ml; 0.66±0.57 ng/ml; 11.66±7.37 ng/ml; caput epididymis; 5.00±1.73 ng/ml; 2.33±1.52 ng/ml; 5.00±2.64 ng/ml; 1.33±0.57 ng/ml; 5.66±1.15 ng/ml; corpus epididymis; 1.33±0.57 ng/ml; 0.66±0.57 ng/ml; 4.00±2.64 ng/ml; 0.66±0.57 ng/ml; 4.33±2.30 ng/ml; cauda epididymis: 1.00±0.00 ng/ml; 0.66±0.57 ng/ml; 1.66±0.57 ng/ml; 1.00 ± 0.00 ng/ml; 2.00±1.73 ng/ml; ductus deferens: 3.66±2.51 ng/ml; 0.66±0.57 ng/ml; 3.00±1.00 ng/ml; 1.00±0.00 ng/ml and 3.66±1.15 ng/ml. Statistical analysis showed that the administration of EE only increased testosterone concentration in testes had significant effect (P 0.05). From this study, it can be concluded that the EE has the potential to improve spermatogenesis and sperm quality through increasing the testosterone concentration in the local male goats.

Gestational and lactational exposure to di-isobutyl phthalate via diet in maternal mice decreases testosterone levels in male offspring

Phthalates are a large family of ubiquitous environmental chemicals suspected of being endocrine disruptors, with exposure to these chemicals during prenatal and postnatal development possibly resulting in reproductive disorders. Di-isobutyl phthalate (DiBP) is widely used in consumer and industrial products, and although its exposure in the general population has increased in recent years, the mechanisms behind DiBP-induced reproductive disorders in male offspring remain unclear. Here, pregnant mice were exposed to 0 or 450 mg/kg bw/day DiBP via diet from gestation day (GD) 0 to GD21. Until postnatal day 21 (PD21), half of the exposed pups were also exposed to DiBP by lactation (TT), while the rest were not (TC). Half of each group were sacrificed on PD21, with the remaining mice fed a normal diet until PD80 (TCC and TTC, respectively). Reproductive toxicological parameters such as relative organ weights and testosterone levels were determined in male offspring on PD21 and PD80 and sperm quality was tested on PD80. Maternal exposure (pregnancy and lactation) led to decreased serum and testis testosterone concentrations, accompanied by decreased expression of 3β-hydroxysteroid dehydrogenase (3β-HSD) and cytochrome P450 family 11 subfamily A member 1 (CYP11A1) in PD21 pups and PD80 adults. Furthermore, the TTC group showed decreased epididymis sperm concentration and motility. Taken together, DiBP exposure in early life (prenatal and postnatal) impaired male reproductive function in later life, possibly by interfering with testosterone levels and CYP11A1, which might be a major steroidogenic enzyme targeted by DiBP or other phthalates.

Cold exposure inhibits hypothalamic Kiss-1 gene expression, serum leptin concentration, and delays reproductive development in male Brandt's vole (Lasiopodomys brandtii).

Cold commonly affects growth and reproductive development in small mammals. Here, we test the hypothesis that low ambient temperature will affect growth and puberty onset, associated with altered hypothalamic Kiss-1 gene expression and serum leptin concentration in wild rodents. Male Brandt's voles (Lasiopodomys brandtii) were exposed to cold (4 ± 1 °C) and warm (23 ± 1 °C) conditions from the birth and sacrificed on different developmental stages (day 26, day 40, day 60, and day 90, respectively). Brandt's voles increased the thermogenic capacity of brown adipose tissue, mobilized body fat, decreased serum leptin levels, and delayed the reproductive development especially on day 40 in the cold condition. They increased food intake to compensate for the high energy demands in the cold. The hypothalamic Kiss-1 gene expression on day 26 was decreased, associated with lower wet testis mass and testis testosterone concentration on day 40, in the cold-exposed voles compared to that in the warm. Serum leptin was positively correlated with body fat, testis mass, and testosterone concentration. These data suggested that cold exposure inhibited hypothalamic Kiss-1 gene expression during the early stage of development, decreased serum leptin concentration, and delayed reproductive development in male Brandt's voles.

Differential investment into testes and sperm production in alternative male reproductive tactics of the African striped mouse (Rhabdomys pumilio)

Males that follow alternative reproductive tactics might differ in their investment into testis development and sperm production. The resource-allocation hypothesis predicts that males following a sneaker tactic should invest more into sperm production than dominant territorial males which should invest more into mate guarding. This hypothesis is supported by studies in species where individual males cannot switch between tactics (fixed tactics). Here we present the first data for a species where males can switch between tactics (plastic tactics). We studied African striped mice (Rhabdomys pumilio) in captivity, mimicking three tactics observed in the field: philopatric group-living males, singly-housed males representing roaming males, and group-living breeding males. We measured quantitative and qualitative reproductive traits, as well as serum and testis hormone concentrations. We found no support for the resource-allocation hypothesis, since breeding and singly-housed males invested similarly in testes and sperm. However, philopatric males had significantly smaller testes and epididymides, lower sperm counts, lower testosterone and higher corticosterone levels than males of the two other tactics. Philopatric males did not reach a larger body mass than singly-housed males with well developed reproductive traits, indicating that they did not trade investment in sperm production against growth. Interestingly, testis testosterone concentrations of philopatric males did not differ from those of other males. Our data suggest that philopatric males are reproductively suppressed by the breeding male, but might be ready to increase their serum testosterone levels when social and environmental conditions allow for this physiological switch accompanying the behavioral switch between tactics.

Spermatogenic Defects in a New Inbred Strain SD/gShi Male Rat with Small Testes.

A new inbred strain SD/gShi male rat with small testes was studied from the reproductive, histopathological and endocrinological viewpoints from 3 to 35 weeks of age. SD/gShi males showed only a slight increase in sperm production at puberty, in contrast to a rapid increase in normal SD males. At 6 weeks of age, spermiation became detectable in both SD/gShi and normal SD males, however, the numbers of spermatocytes and round spermatids per Sertoli cell in SD/gShi males were less than those in normal SD males. Moreover, the number of round spermatids per Sertoli cell did not increase in SD/gShi males at puberty, while they did in normal SD males. Histological analysis of germ cell numbers in SD/gShi males indicated that the lower numbers of spermatocytes and spermatids are caused by suppression of germ cell proliferation at the step from the spermatogonium to the preleptotene spermatocyte. Adult SD/gShi males showed normal fertilization ability, however, they had only 10-20% of sperm production in normal adult SD males and showed depressed sperm motion. Plasma total testosterone in SD/gShi males was lower for all ages, though testis testosterone concentration was normal. Plasma gonadotropin concentrations, especially FSH, remained higher than in normal SD males, suggesting that the spermatogenic defects are not caused by gonadotropin deficiency. These results indicate that the SD/gShi male is characterized by spermatogenic defects at the preleptotene spermatocyte step which occur from the first spermatogenic wave. The SD/gShi male rat can serve as a useful model for studying spermatogenesis in rats.

Steroid hormone content of the gonads of the tammar wallaby during sexual differentiation.

The gonads of the tammar wallaby, Macropus eugenii, are sexually indifferent at birth (Day 0) despite the fact that phenotypic sexual differentiation has already commenced as evidenced by the presence of a scrotum in males and mammary anlagen in females. The seminiferous cords of the testis first become clearly recognizable on Day 2 of pouch life, and ovarian differentiation is recognizable by Day 10. To monitor the endocrine development of the gonads during sexual differentiation of the urogenital tract, we measured the steroid hormone content in 92 pools of gonads from male and female tammar pouch young from the day of birth to 206 days of pouch life. Progesterone, estradiol, and dihydrotestosterone concentrations were low (less than 0.05 ng/mg protein) in both ovaries and testes at all stages examined, and testosterone concentrations were uniformly low in ovaries. Testosterone concentrations in testes were low on Days 0-4, averaging about 0.2 ng/mg protein; they rose by Days 5-10 to an average of 0.9 ng/mg protein, remained elevated until about Day 40, and thereafter fell to values similar to those in the ovaries. The phallus and urogenital sinus were able to convert testosterone to dihydrotestosterone from the earliest stages examined (Days 10 and 11). Thus in the tammar wallaby, as in eutherian mammals, testosterone is the androgen secreted by the developing testis, and dihydrotestosterone is formed in certain androgen target tissues.(ABSTRACT TRUNCATED AT 250 WORDS)

The effect of guanethidine treatment of testicular blood flow and testosterone production in rats

Testicular blood flow was measured by means of Xenon-133 clearance in control rats and rats treated with guanethidine for 3 weeks. Plasma and testis testosterone concentrations were also measured, and the effect of hCG-treatment was examined. No difference in testicular blood flow between the control group and the guanethidine-treated group was found. However, in guanethidine-treated rats, plasma and testis testosterone concentrations after hCG-treatment were significantly decreased. The results may indicate that adrenergic nerves are involved in the regulation of Leydig cell function.

Inhibition of testosterone biosynthesis by ethanol. Relation to hepatic and testicular acetaldehyde, ketone bodies and cytosolic redox state in rats.

In experiments in which liver and testis freeze-stops were performed on pentobarbital-anaesthetized rats, ethanol (1.5 g/kg body wt.) reduced plasma testosterone concentration from 13.1 to 3.2 nmol/litre. 4-Methylpyrazole abolished the ethanol-induced hepatic and testicular increase in the lactate/pyruvate ratio, and the testicular acetaldehyde level, but did not diminish the reduction in plasma testosterone concentration. In testes, but not in liver, ethanol decreased the 3-hydroxybutyrate/acetoacetate ratio, and 4-methylpyrazole did not prevent this effect. In experiments in which freeze-stop was performed after cervical dislocation, ethanol decreased the testis testosterone concentration from 590 to 220 pmol per g wet wt. The effects of ethanol and 4-methylpyrazole on testis acetaldehyde, lactate/pyruvate and 3-hydroxybutyrate/acetoacetate ratios were the same as found during anaesthesia. The NAD+-dependent ethanol oxidation capacity in testis ranged from 0.1 to 0.2 mumol/min per g wet wt. and seemed to be inhibited by 4-methylpyrazole both in vivo and in vitro. In additional experiments, ethanol doses between 0.3 and 0.9 g/kg body wt. did not alter the plasma testosterone concentration in rats treated, or not treated, with cyanamide, which induced elevated acetaldehyde levels in blood and testes. The results suggest that ethanol-induced inhibition of testosterone biosynthesis was not caused by extratesticular redox increases, or by extra- or intra-testicular acetaldehyde per se. The inhibition is accompanied by changes in testicular ketone-body metabolism.

Morphological and Endocrinological Differences between the Abdominal Testes in Bilateral and Unilateral Cryptorchid Rats

Using a new experimental model of cryptorchism in rats, where testicular descent was prevented, testicular development and function were studied in bilateral and unilateral cryptorchid animals Morphometric and radioimmunological techniques were used. Up to 30 days after birth testicular development was identical in the two types of abdominal testes but in adult rats differences were observed. In these rats spermatogenesis was damaged to a similar extent, but total tubular length and testicular weight were increased in the bilateral abdominal testes. Moreover, in these testes, the volume density of Leydig cells, the total Leydig cell mass, the average Leydig cell size and the testis testosterone concentration were larger than in unilateral abdominal testes. It is suggested that the impaired spermatogenesis seen in both kinds of abdominal testes may be unrelated to Leydig cell function.

STUDIES OF THE HUMAN TESTIS. XI. LEYDIG CELL CLUSTERS AND LEVELS OF INTRATESTICULAR TESTOSTERONE AND 20α-DIHYDROPROGESTERONE1

Testosterone concentration in testes of 23 men, ages 51 to 90, was determined as 490 +/- 172 ng/g tissue (M +/- S.D.) and 20 alpha-dihydroprogesterone concentration as 10.0 +/- 2.3 ng/g tissue (M +/- S.D.) in 18 men of the same patient group. Leydig cells were estimated by the number of Leydig cell clusters per tubule. There was a high correlation (r = 0.88, p less than .001) of the Leydig cell index with intratesticular testosterone. It is proposed that the Leydig cell cluster index provides a direct index of steroid biosynthetic activity in the human testis as reflected in intratesticular testosterone levels. Although there was no significant correlation of 20 alpha-dihydroprogesterone levels in the testis with either the Leydig cell index or intratesticular testosterone, the high level of 20 alpha-dihydroprogesterone compared to peripheral levels suggests its production by the testis.

Comparative toxicity of polychlorinated biphenyls and dibenzofurans in rats

Comparative Toxicity of Polychlorinated Biphenyls and Dibenzofurans in Rats. Oishi, S., Morita, M., and Fukuda, H. (1978). Toxicol. Appl. Pharmacol. 43, 13–22 (1978). The toxic effects of polychlorinated biphenyl (PCB) mixtures and polychlorinated dibenzofurans (PCDFs) were compared on male SD-derived rats fed diets containing 100 ppm of PCB and 1 or 10 ppm of PCDF for 4 weeks. Rats fed 10-ppm diets of PCDF developed chloracne-like lesions on the ears within 3 weeks. PCDF markedly and PCB slightly depressed body weight gain. In rats fed diets containing 10 ppm of PCDF, significantly decreased thymus, ventral prostate, and seminal vesicle weights were found. Hemoglobin and hematocrit values were decreased in rats fed either diet containing PCDF. PCBs produced very minimal effects on thymus and accessory sex organ weights and hematologic values. Both PCB and PCDF increased serum cholesterol concentrations and cholinesterase activity and decreased triglyceride concentrations and leucine aminopeptidase activity. PCDF decreased serum glutamic-pyruvic transaminase activity and testosterone concentration in testis, and increased serum glutamicoxaloacetic transaminase activity. These results suggest that, in the rat, PCDFs are more toxic substances than PCBs when administered in the diet.

Influence of DDT, DDVP and malathion on FSH, LH and testosterone serum levels and testosterone concentration in testis.

Groups of adult male rats were treated with DDT, DDVP or malathion orally for two or three weeks. Body weight and testis weight did not change. FSH and LH levels in serum also remained unchanged, whereas that of testosterone was decreased by DDT. This substance also diminished the concentration of testosterone in the testis. Therefore, the previously observed damage to spermatogenesis by DDT are assumed to be caused by a lack of androgens. Those following treatment with DDVP or malathion seem to be due to a direct cytotoxic effect.

The effects of barbiturate anesthesia and laparotomy on testis and plasma testosterone in rats.

Abstract Plasma and testis testosterone concentrations were measured in rats 2.5 and 24 h after barbiturate (thiomebumal) anesthesia and 24 h after laparotomy. The testicular concentration of testosterone was significantly reduced after barbiturate treatment but plasma testosterone concentration was not significantly affected. Laparotomy did not cause any effect on plasma or testis testosterone concentrations.

No effect of oxygen in vivo on plasma or testis testosterone in rats and no induction of testicular superoxide dismutase

Male rats were exposed to 100% O 2 for 24 h in a temperature-controlled cage and compared to a control group, similarly exposed to air. No effect of O 2 was observed on plasma testosterone concentrations or on testis testosterone concentrations. The rat testis was found to contain a comparatively high level of superoxide dismutase activity, an enzyme believed to protect against the toxicity of oxygen. Oxygen did not induce the enzyme in testis under these conditions.

Testicular development and testosterone concentrations in the testis and plasma of young male shrews ( Suncus murinus)

Testicular development and testosterone concentrations in the peripheral plasma and testes of young, adult, and castrated male musk shrews ( Suncus murinus) were examined. Fifty immature, 24 adult, and eight castrated males were used. Immature males ranged from 5–45 days of age. Plasma and testis homogenates were assayed for testosterone by radioimmunoassay. Testes were examined histologically for spermatogenic development. Plasma testosterone concentrations increased gradually from Day 5 to Day 24, then rapidly to Day 30. There was a sharp decrease between Day 30 and 33, then a gradual increase to Day 45. Testis testosterone concentrations followed the same pattern, except that on Day 5, the concentration was significantly higher than on Day 10. Adult males had higher testis testosterone and lower plasma testosterone concentrations than Day 45 males. Castrated males had barely detectable plasma testosterone levels. Testis weights increased linearly with age, except for a slight decrease between Day 30 and 33. Spermatogenic development was already initiated by Day 5. Cap-phase spermatids were present on Day 23, acrosome-phase spermatids on Day 30, and mature spermatozoa on Day 31. Epididymal sperm were present by Day 45.