Involvement of lysosomal enzymes in flutamide-induced stimulation of rat testis

Nitrobenzene-induced hormonal disruption, alteration of steroidogenic pathway, and oxidative damage in rat: protective effects of Vernonia amygdalina

Background

Infertility is a global health burden which affect more than 15% of couples’ population. An impaired hormonal balance, oxidative stress and alteration in the physiological function of the reproductive organ are factors leading to infertility. The present study investigated the protective role of methanolic leaf extract of Vernonia amygdalina (MLVA) against Nitrobenzene-induced oxidative testicular damage and hormonal imbalance in rats. Thirty sexually active male wistar rats were sorted into five groups, each group containing six rats. Group I received distilled water while 100 mg/kg bw of Nitrobenzene was administered to groups (II, III, IV and V) to induce testicular damage and hormonal imbalance. Group III and IV were treated with oral administration of 200 mg/kg bw and 400 mg/kg bw of MLVA respectively and group V with vitamin E for 14 days.

Results

Nitrobenzene-treated rats showed significant (P < 0.05) decrease in the body weight gain, testis and epididymis weights. However, upon administration of MLVA or vitamin E, these changes were significantly reversed in Nitrobenzene-treated rats. Also, Nitrobenzene significantly (P˂0.05) induced endocrine disruption as shown by decreased activities level of serum Thyroid stimulating hormone (TSH), luteinizing hormone (LH), follicle stimulating hormone (FSH), prolactin, testosterone, triiodothyronine (T3), and tetraiodothyronine (T4). Administration of Nitrobenzene also induced oxidative damage as shown by increased level of testicular lipid peroxidation (MDA), and decreased levels of glutathione (GSH). Histological studies of the testes revealed mild congestion of interstitial vessels and oedema in rats administered Nitrobenzene only.

Conclusion

Taken together, MLVA obliterated the adverse effects of Nitrobenzene on the antioxidant enzymes, markers of testicular oxidative damage, endocrine and testicular structure in rats.

Protective effect of Abutilon indicum against lead-induced reproductive toxicity in male Wistar rats

Despite ample literature on the toxic impact of lead on the environment and health, the exact mechanism of pathogenesis/toxicity is not clearly known. Because it is well established that lead induces oxidative stress, it is assumed that exposure to antioxidants may reduce the toxic impact of lead. In this study, we evaluated the impact of coadministration of the methanolic root extract of a plant Abutilon indicum (50, 100, 200 mg kg ^-1 b.wt.) in mitigating the toxic impact of lead on the reproductive system of rats. In brief, Wistar rats were exposed to lead acetate in drinking water with or without coadministration of plant root extract and compared with that of control animals. After 45 days of exposure as outlined above, the animals were killed and the reproductive toxicity was assessed by sperm parameters, hormone and antioxidant enzyme assays, and testis histopathology. Significant reduction in testis weight, sperm count, testosterone levels, and antioxidant enzymes levels such as Superoxide Dismutase, Catalase, and Glutathione peroxidase was seen in lead-treated animals, confirming the toxic impact. The coadministration of A. Indicum (100 and 200 mg kg ^-1 b.wt.) was found to bring the studied parameters close to the levels seen in untreated (control) animals. Our findings are indicative of the protective nature of A. Indicum against lead-induced reproductive toxicity in a dose-dependent manner. However, further characterization of the root extract is required to elucidate the probable mechanism of protection.

Reversible Testicular Toxicity of Piperine on Male Albino Rats

Background:

Piperine was widely used in traditional medicine for inducing sterility and abortion.

Objective:

To evaluate the effect of the piperine on testis of male albino rats

Materials and Methods:

Adult male rats were divided into four groups (n = 12). Group I (control): Rats were given vehicle p.o. i.e. 0.5% carboxymethyl cellulose in normal saline daily for 60 days, Group II (ED): Rats received piperine at a dose of 10 mg/kg body weight (b.w.) daily, Group III (E4D): Rats received piperine at a dose of 10 mg/kg b.w. on every 4^th day, Group IV (E7D): Rats received piperine at a dose of 10 mg/kg b.w. on every 7^th day. Half of the animals from each group were sacrificed after the treatment period (60 days), and the remaining were kept for drug-free withdrawal period (60 days) and then sacrificed.

Results:

Piperine significantly decreased the reproductive organ weights in groups ED and E4D. Piperine induced hormonal imbalance by altering the serum levels of follicle-stimulating hormone, luteinizing hormone, sex hormone binding globulin, serum, and testicular testosterone in groups ED and E4D. Furthermore, piperine decreased the activity of germ cell markers and Leydig cellular steroidogenic enzymes in the groups ED and E4D after 60 days. All the above-altered values returned to normal levels after withdrawal period. Histopathological findings also supported the above findings.

Conclusion:

From the above data, it can be concluded that piperine could be a good lead molecule for the development of reversible oral male contraceptive.

SUMMARY

Piperine was employed for the contraceptive purposes in traditional medicine

Piperine significantly impaired the spermatogenesis by decreasing the testicular hormone synthesis in groups ED and E4D

Piperine disrupted the testicular antioxidant system by promoting the ROS production and hydroxyl radical generation in rat testis in groups ED and E4D

Histopathological evidence supported the disruption of spermatogenesis by piperine

All the effects of piperine after the treatment period (i.e. 60 days) were back to normal after the withdrawal period (i.e., after 120 days).

Protective effect of Satureja montana extract on cyclophosphamide-induced testicular injury in rats

The present study investigated the protective effect of Satureja montana extract against cyclophosphamide-induced testicular injury in rats. Total phenolic and flavonoid contents of the extract were 1.03% and 0.34%w/w of dry herb expressed as chlorogenic acid and quercetin, respectively. HPLC analysis identified caffeic, syringic and rosmarinic acids as the chief phenolic acids, and rutin as the major flavonoid in the extract. Oral daily administration of S.montana extract (50mg/kg/day) for 7days before and 7days after an intraperitoneal injection of cyclophosphamide (200mg/kg) restored the reduced relative testicular weight, serum testosterone level and testicular alkaline phosphatase activity, raised the lowered testicular sorbitol dehydrogenase and acid phosphatase activities, and decreased the elevated testicular hemoglobin absorbance. It also attenuated lipid peroxidation, restored the lowered glutathione content, glucose-6-phosphate dehydrogenase, glutathione peroxidase and glutathione reductase activities, and improved total antioxidant capacity. Moreover, S.montana extract mitigated testicular DNA fragmentation, decreased the elevated Fas and Bax gene expression, up-regulated the decreased Bcl-2 and peroxisome proliferator-activated receptor-gamma (PPAR-γ) gene expression and normalized Akt1 protein level. Histopathological investigation confirmed the protective effects of the extract. Conclusively, S.montana extract protects the rat testis against cyclophosphamide-induced damage via anti-oxidative and anti-apoptotic mechanisms that seem to be mediated, at least in part, by PPAR-γ and Akt1 up-regulation.

Recovery of lead-induced suppressed reproduction in male rats by testosterone

The objective of the present study was to investigate the effects of testosterone in recuperation of lead-induced suppressed reproduction in adult male rats. Lead acetate was administered orally to adult male rats (95 ± 5 days) at dosage level of 0.05 and 0.15% for 55 days through drinking water and injected intraperitoneally with either testoviron depot at a dose of 4.16 mg kg(-1) body weight or vehicle alone on days 1, 7 and 14 respectively. At the end of treatment, control and treated males were cohabited with untreated normal-cycling females. After cohabitation for 5 days, all the male rats were killed and weights of reproductive organs were determined. Significant increase in the indices of testis, epididymis, seminal vesicles, vas deferens and prostate glands was observed in testosterone (T)-treated rats when compared to those of lead-exposed rats. Testosterone treatment significantly increased epididymal sperm count, motile spermatozoa, viable spermatozoa and HOS tail-coiled spermatozoa and also the activity levels of testicular 3β- and 17β-hydroxysteroid dehydrogenases when compared to those of lead-exposed males. From the results, it can be hypothesised that supplementation of testosterone mitigated lead-induced suppressed reproduction in male rats.

Influence of Tribulus terrestris on testicular enzyme in fresh water ornamental fish Poecilia latipinna

The influence of Tribulus terrestris on the activities of testicular enzyme in Poecilia latipinna was assessed in lieu of reproductive manipulation. Different concentrations of (100, 150, 200, 250, and 300 mg) Tribulus terrestris extract and of a control were tested for testicular activity of enzymes in Poecilia latipinna for 2 months. The testis and liver were homogenized separately in 0.1 mol/l potassium phosphate buffer (0.1 mol/l, pH 7.2). The crude homogenate was centrifuged, and supernatant obtained was used as an enzyme extract for determination of activities. The activities of testicular functional enzyme ALP, ACP, SDH, LDH, and G6PDH levels were changed to different extent in treated groups compared with that of the control. The total body weight and testis weight were increased with the Tribulus terrestris-treated fish (Poecilia latipinna). These results suggest that Tribulus terrestris induced the testicular enzyme activity that may aid in the male reproductive functions. It is discernible from the present study that Tribulus terrestris has the inducing effect on reproductive system of Poecilia latipinna.

Protective role of Centella asiatica on lead-induced oxidative stress and suppressed reproductive health in male rats

Centella asiatica has been mentioned in ancient ayurvedic text of the Indian system of medicine for its properties to promote intelligence. The objective of the present study was to investigate the beneficial effects of C. asiatica on lead-induced oxidative stress and suppressed reproductive performance in male rats. Significant decrease in the weights of testes and epididymis were observed in lead treated animals. Exposure to lead acetate significantly increased malondialdehyde levels with a significant decrease in the superoxide dismutase and catalase activities in the liver, brain, kidneys and testes of rats. Epididymal sperm count, viable sperms, motile sperms and HOS-tail coiled sperms decreased significantly in lead-exposed rats. Testicular steroidogenic enzyme activities also decreased significantly in lead-exposed rats. No significant changes in the selected reproductive variables were observed in the plant extract alone treated rats. Whereas, co-administration of aqueous extracts of C. asiatica to lead exposed rats showed a significant increase in the weights of reproductive organs, reduction in lead-induced oxidative stress in the tissues and improvement in selected reproductive parameters over lead-exposed rats indicating the beneficial role of C. asiatica to counteract lead-induced oxidative stress and to restore the suppressed reproduction in male rats.

Lead acetate induced reproductive and paternal mediated developmental toxicity in rats

Lead was administered orally to adult male rats at exposure level of 273 or 819 mg/L (0.05% or 0.15% lead acetate, respectively) for 45 days via drinking water. At the end of the exposure period, control and experimental males were mated with untreated females. Of the females mated with treated males, 73.3% in the 0.05% group and 53.33% in the 0.15% group showed copulatory plugs. Significant decrease in number of implantations and pre- and post-implantation loss was also observed in females mated with treated males. Significant decrease in the weight of the reproductive organs, reduction in epididymal sperm count, motile sperm and viable sperm were observed in lead-exposed rats indicating decreased sperm production and deteriorated sperm quality. Significant decrease in serum testosterone levels were also observed in treated rats indicating decreased steroidogenesis. The decreased serum testosterone levels and deteriorated sperm quality might be responsible for the suppressed reproduction in rats after exposure to lead.

Protective role of curcumin on lindane induced reproductive toxicity in male Wistar rats

The aim of this study was to explore the adverse effects of lindane pesticide on testes and epididymus weight, sperm head counts, sperm motility, abnormal changes in sperm morphology, biochemical changes in endogenous antioxidants and oxidative enzymes in male wistar rats as well as to assess ameliorating role of 'curcumin'. Rats were exposed daily to lindane (30 mg/kg bw) for 14 and 28 days and administered with curcumin (100 mg/kg bw) in pretreatment, post treatment and combination groups. We observed decrease (p < 0.001) in testes and cauda epididymus weight, decrease (p < 0.001) in testicular sperm head count, increase (p < 0.001) in abnormal tail morphology (headless tail, multiple tail, broken tail, coiled tail and bent tail), abnormal head morphology (excessive hook, amorphous head, pin head, short head, blunt hook and detached hook) and decrease (p < 0.001) in sperm motility after lindane exposure, as compared to control. There was (p < 0.01) decline in superoxide dismutase, catalase and glutathione-s-transferase activity on lindane exposure, however, no change (p > 0.05) was observed in glutathione level. Lipid peroxidation was (p < 0.01) enhanced on lindane exposure as compared to control. Curcumin administration was able to ameliorate lindane induced reproductive toxicity in pretreatment, post treatment and combination groups. The study indicated that even after 14 days of metabolism, toxic effects of lindane were evident.

Di-(2 ethylhexyl) phthalate and flutamide alter gene expression in the testis of immature male rats

We previously demonstrated that the androgenic and anti-androgenic effects of endocrine disruptors (EDs) alter reproductive function and exert distinct effects on developing male reproductive organs. To further investigate these effects, we used an immature rat model to examine the effects of di-(2 ethylhexyl) phthalate (DEHP) and flutamide (Flu) on the male reproductive system. Immature male SD rats were treated daily with DEHP and Flu on postnatal days (PNDs) 21 to 35, in a dose-dependent manner. As results, the weights of the testes, prostate, and seminal vesicle and anogenital distances (AGD) decreased significantly in response to high doses of DEHP or Flu. Testosterone (T) levels significantly decreased in all DEHP- treated groups, whereas luteinizing hormone (LH) plasma levels were not altered by any of the two treatments at PND 36. However, treatment with DEHP or Flu induced histopathological changes in the testes, wherein degeneration and disorders of Leydig cells, germ cells and dilatation of tubular lumen were observed in a dose-dependent manner. Conversely, hyperplasia and denseness of Leydig, Sertoli and germ cells were observed in rats given with high doses of Flu. The results by cDNA microarray analysis indicated that 1,272 genes were up-regulated by more than two-fold, and 1,969 genes were down-regulated in response to DEHP, Flu or both EDs. These genes were selected based on their markedly increased or decreased expression levels. These genes have been also classified on the basis of gene ontology (e.g., steroid hormone biosynthetic process, regulation of transcription, signal transduction, metabolic process, biosynthetic process...). Significant decreases in gene expression were observed in steroidogenic genes (i.e., Star, Cyp11a1 and Hsd3b). In addition, the expression of a common set of target genes, including CaBP1, Vav2, Plcd1, Lhx1 and Isoc1, was altered following exposure to EDs, suggesting that they may be marker genes to screen for the anti-androgenic or androgenic effects of EDs. Overall, our results demonstrated that exposure to DEHP, Flu or both EDs resulted in a alteration of gene expression in the testes of immature male rats. Furthermore, the toxicological effects of these EDs on the male reproductive system resulted from their anti-androgenic effects. Taken together, these results provide a new insight into the molecular mechanisms underlying the detrimental impacts of EDs, in regards to anti-androgenic effects in humans and wildlife.

Effects of diallyl sulfide and zinc on testicular steroidogenesis in cadmium-treated male rats

Cadmium (Cd) is one of the environmental pollutants that affect various tissues and organs including testis. Harmful effect of cadmium on testis is known to be germ cell degeneration and impairment of testicular steroidogenesis. In the present study, the effect of diallyl sulfide (DAS), a sulfur-containing volatile compound present in garlic, and zinc (Zn) was investigated on cadmium-induced testicular toxicity in rats. Male adult Wistar rats treated with cadmium (2.5 mg/kg body wt, five times a week for 4 weeks) showed decreased body weight, paired testicular weight, relative testicular weight, serum testosterone, luteinizing hormone, follicle-stimulating hormone, and testicular total antioxidant capacity (TAC) and protein levels. Testicular steroidogenic enzymes, such as 3beta-hydroxysteroid dehydrogenase (3beta-HSD) and 17beta-hydroxysteroid dehydrogenase (17beta-HSD), and marker enzymes, such as sorbitol dehydrogenase (SDH), lactate dehydrogenase (LDH), acid phosphatase (ACP), alkaline phosphatase (ALP), and glucose-6-phosphate dehydrogenase (G6PD), showed a significant decrease in activities whereas that of gamma-glutamyl transferase was significantly increased after cadmium exposure. The results have revealed that concurrent treatment with DAS or zinc restored key steroidogenic enzymes, SDH, LDH, and G6PD and increased testicular weight significantly. DAS restored the TAC level and increased testosterone level and relative testicular weight significantly. Zinc restored testicular protein level and body weight. It can be concluded that cadmium causes testicular toxicity and inhibits androgen production in adult male rats probably by affecting pituitary gonadotrophins and that concurrent administration of DAS or zinc provides protection against cadmium-induced testicular toxicity.

Effects of vitamin E on reactive oxygen species-mediated 2,3,7,8-tetrachlorodi-benzo-p-dioxin toxicity in rat testis

This study was undertaken to investigate whether treatment with vitamin E protects rat testis from oxidative stress induced by 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). Male rats of Wistar strain were administered TCDD at doses of 1, 10 and 100 ng kg(-1) body wt. day(-1) for 45 days. Other groups of animals were co-administered TCDD (1, 10 and 100 ng kg(-1) body wt. day(-1)) and vitamin E (20 mg kg(-1) body wt. day(-1)) for 45 days. Animals administered TCDD and those co-administered TCDD and vitamin E did not show any significant change in body weight. Administration of TCDD decreased the weights of the testis, epididymis, seminal vesicles and ventral prostate. The daily sperm production decreased in the animals administered TCDD from the control values of 22.19 +/- 2.67 to 13.10 +/- 3.16 x 10(6). There was a significant decline in the activities of superoxide dismutase, catalase, glutathione reductase and glutathione peroxidase with concomitant increased levels of hydrogen peroxide and lipid peroxidation. Co-administration of TCDD and vitamin E did not show any significant changes in the weights of the testis, epididymis, seminal vesicles and ventral prostate. The daily sperm production remained unchanged in the animals co-administered TCDD and vitamin E. The activities of antioxidant enzymes and the levels of hydrogen peroxide and lipid peroxidation did not change in the animals co-administered TCDD and vitamin E. The results suggested that administration of TCDD induces oxidative stress in testis, and vitamin E could impart a protective effect against TCDD-induced oxidative stress.

Effect of methoxychlor on the antioxidant system in mitochondrial and microsome-rich fractions of rat testis

Methoxychlor, an environmental contaminant, which is widely used as a pesticide in many countries, has been shown to induce reproductive abnormalities in male rats. The precise nature and mechanism of action of methoxychlor on the male reproductive system is not clear. In the present study, we have sought to investigate the induction of oxidative stress in the testis of rat after exposure to methoxychlor. Methoxychlor (1, 10, and 100 mg kg(-1) body weight per day) was administered orally to the rats for 45 days. After 24 h of the last treatment the animals were killed using anesthetic ether. The body weight of the animals administered with methoxychlor did not show any significant change. The weights of the testis, epididymis, seminal vesicles and ventral prostate decreased significantly in 100 mg dose but remained unchanged in 1 and 10 mg doses. Mitochondrial and microsome-rich fractions of the testis were obtained by the method of differential centrifugation. The activities of antioxidant enzymes such as superoxide dismutase, catalase, glutathione reductase and glutathione peroxidase decreased significantly in the animals treated with methoxychlor in a dose-dependent manner in the mitochondrial and microsome-rich fractions of rat testis. The levels of hydrogen peroxide generation (H(2)O(2)) and lipid peroxidation increased in mitochondrial and microsome-rich fractions of the testis of the rats treated with methoxychlor. The results suggested that the low to medium doses of methoxychlor elicit depletion of antioxidant enzymes and concomitant increase in the levels of H(2)O(2) and lipid peroxidation differentially in mitochondrial and microsome-rich fractions of rat testis. In conclusion, the adverse effect of methoxychlor on male reproduction could be due to the induction of oxidative stress in testis.

The effect of methoxychlor on the epididymal antioxidant system of adult rats

Methoxychlor is widely used as a pesticide in many countries and has been shown to induce reproductive abnormalities in male rats, causing reduced fertility. The mechanism of action of methoxychlor on the male reproductive system is not clear. In the present study we investigated whether administration of methoxychlor induces oxidative stress in the epididymis and epididymal sperm of adult rats. Methoxychlor (50, 100, or 200 mg/kg body weight/day) was administered orally for 1, 4, or 7 days. The animals were killed using anesthetic ether 24 h after of the last treatment. Epididymal sperm were collected by cutting the epididymis into small pieces in Ham's F-12 medium at 35 degrees C. The body weight and weights of the testis, liver, and kidney did not show any significant changes in the methoxychlor-treated rats. The weight of the epididymis, seminal vesicles, and ventral prostate as well as epididymal sperm counts decreased after 50, 100, or 200 mg/kg/day for 7 days but remained unchanged after shorter courses of treatment. Epididymal sperm motility was decreased in a dose-dependent manner in the animals treated with methoxychlor for 4 or 7 days. The activities of the antioxidant enzymes superoxide dismutase, catalase, glutathione reductase, and glutathione peroxidase were decreased while the levels of hydrogen peroxide and lipid peroxidation were increased in the epididymal sperm as well as in the caput, corpus, and cauda epididymis after 4 or 7 days of treatment. The activities of superoxide dismutase decreased while the levels of lipid peroxidation increased in the liver but not in the kidney in all groups. Co-administration of the antioxidant vitamin E (20 mg/kg body weight/ day) to the 200 mg/kg/d methoxychlor-treated rats for 7 days prevented significant changes in the antioxidant systems in the epididymis and epididymal sperm and prevented alterations in sperm counts and motility. The results indicated that methoxychlor induces oxidative stress in the epididymis and epididymal sperm by decreasing antioxidant enzymes, possibly by inducing reactive oxygen species. In conclusion the adverse effect of methoxychlor on the male reproduction could be due to induction of oxidative stress.

Effect of flutamide on the physiological status of epididymis and epididymal sperms

Flutamide, a pure antiandrogen, increases the levels of plasma luteinizing hormone but antagonizes the biological expression of androgen on target organs. Flutamide was administered to rats to study the effect of altered availability of hormones on the functional status of epididymis. The weights of ventral prostate, seminal vesicles and epididymis showed antiandrogenic effects of flutamide. However, increased activity of kidney beta-glucuronidase reflected increased availability of testosterone. The concentrations of protein and DNA along with the activities of acid phosphatase and hyaluronidase decreased in flutamide-treated rats. The activities of acid phosphatase and hyaluronidase in epididymal sperms along with protein concentration increased in flutamide-treated rats. Alteration of epididymal function by treatments affecting lysosomal stability was indicated.

Partial purification and properties of lysosomes from rabbit testes

Rabbit testes lysosomes were prepared by differential centrifugation and density gradient centrifugation on Percoll. The particulate material sedimented at 1.054 g/cm3. The enrichment in the activities of lysosomal marker enzymes was 9-fold. The contamination by other subcellular organelles such as mitochondria, microsomes and the plasma membrane was limited to 0.1% or less. The marker enzymes of isolated lysosomes exhibited bound activity of 80%, thus indicating the integrity of granules. The testicular lysosomes also exhibited osmofragility characteristics.

Effect of ectopic pituitary homograft on the physiological status of rat testis

Pituitary glands grafted under the kidney capsule provide a continuous supply of prolactin due to the absence of hypothalamic inhibitory factor. Increase in the level of prolactin in the rat may affect availability of hormone for reproductive function. Single pituitaries were transplanted under the kidney capsule of male rats. After six weeks of the transplant, the recipient rats were sacrificed and trophic activity of testosterone and intratesticular functions were assessed. The weights of ventral prostate and seminal vesicles, full and empty, showed significant increase from the control value. The activity of beta-glucuronidase in kidney, an androgen inducible enzyme, also increased in comparison with the control value. Incorporation of 32P in the nucleic acid fraction showed an increase. The increased rate of testosterone production and an alteration in spermatogenesis was associated with increased activity of acid phosphatase and decreased activity of beta-glucuronidase. The active mediation of lysosomal enzyme in testicular function as altered by prolactin was indicated.

Effect of intratesticular administration of serum on the physiological status of rat testis

The effect of loss of integrity of seminiferous tubules on intracellular mechanisms in the testis of rats was studied after intratesticular administration of homologous serum. The increased weights of ventral prostate, seminal vesicles and increased activity of beta glucuronidase in kidney reflected an increased availability of testosterone to the target organs. The pulse labelling of 32P in the nucleic acid fraction of testis was significantly increased. The concentration of testicular DNA was increased while the ascorbic acid was slightly decreased. Activities of the lysosomal enzymes, acid phosphatase and beta glucuronidase increased. The involvement of lysosomal enzymes in the testicular function under altered condition was indicated.