Clinical microdose study of gossypol: effect on sperm motility and renal function

This study is part of a series designed to identify the smallest effective gossypol dose for male fertility control. Three men, aged 31-35 years, were administered gossypol, 10 mg/day, orally for 3 months. Urinalysis and assays for plasma hormone values, including cortisol, beta 2-microglobulin, potassium, and BUN, showed no changes during treatment. Forward sperm motility, however, was severely affected by the end of the treatment period (less than 4% forward motility). Sperm density also showed a marked decrease. The subjects developed no undue side effects.

Effect of high energy shock waves on human spermatozoa in vitro

We investigated the effect of high energy shock waves on human spermatozoa in vitro. Human semen samples of proven motility, kept in polyethylene tubes, were subjected to shock waves (100, 500, and 1,000) using a HM3 Dornier lithotripter. A progressive decrease in the spermatozoa vitality was observed with increasing doses of shock waves. Spermatozoa decapitation became significant with increasing doses of shock waves. A progressive decrease in sperm motility was observed following exposure to shock waves, but these changes were not significant.

Demonstration of direct effect of estrogen on rat spermatogenesis

The presence of an estrogen receptor in Leydig cell cytosol suggests that estrogen could have a direct action on Leydig cell function. We have shown earlier the direct effect of estradiol on testosterone biosynthesis. We report in this communication effect of estradiol on spermatogenesis using hypophysectomized rats treated daily for four days with 400 IU hCG/Pregnyl) and 1 IU FSH (Pergonal), a model that eliminates the possibility of feedback effects of estradiol on gonadotropin secretion. Estradiol was administered in subcutaneous silastic capsules. The control animals had empty capsules. The inhibition of spermatogenesis, after estradiol treatment, was marked by the presence of multinucleated giant cells, disorganization of the germinal elements, accumulation of cellular debris and the absence of late spermatid and spermatozoa. These changes in the histoarchitecture of testis were accompanied by the reduction in the diameter of the seminiferous tubules and the thickness of the basement membrane. Morphologically Leydig cells were, however, normal. Inhibition of spermatogenesis was in relation to the amount of estrogen available/administered as estradiol capsule of 0.25 cm did not evoke significant changes in the histology of the testis whereas estradiol capsule of 4 cm caused maximum damage to the spermatogenesis. Similarly progressive damage to the spermatogenesis was quite apparent as the number of days increased after estradiol capsule implantation. Neither high (1600 IU/day/4 days) nor low /5.25 IU/day) doses of hCG synergized the effect of estradiol on spermatogenesis. Testis weight was significantly reduced after estradiol treatment but weight of the epididymis and accessory sex organs did not change. Body weight was also not effected by estradiol treatment.

Studies on low molecular weight follicle stimulating hormone receptor binding inhibitor (FSH-RBI) from ovine testis

Follicle stimulating hormone receptor binding inhibitor (FSH-RBI) has been isolated from the aqueous extracts of ovine testis using Sephadex column chromatography. Sephadex G-75 fraction IV was found to inhibit the binding of (125I) FSH to rat testis receptors. Further purification of Sephadex G-75 fraction on Sephadex G-25 column gave three fractions (I-III). The maximum inhibitory activity to inhibit (125I) FSH binding to rat testis receptor was associated with fraction III only. FSH-RBI exerted a greater inhibitory effect on the formation of the hormone-receptor complex rather than on the dissociation of the preformed complex. FSH-RBI did not inhibit the binding of (125I) LH to rat testis receptors. A significant decrease in the mouse ovarian weight was observed when FSH-RBI was injected to hCG-primed female mice. The molecular weight determination studies show that molecular weight of FSH-RBI is approximately 1400 Daltons.

Ultrastructure of monkey (Macaca radiata) spermatozoa: effect of gossypol in vivo

The present study examines the ultrastructure of ejaculated spermatoza from bonnet monkey, Macaca radiata under normal conditions, with gossypol treatment and during recovery from such treatment. Monkeys were fed orally with gossypol acetic acid (GAA) for 3 months (4 mg/monkey/5 days a week). Semen samples collected by electro-ejaculation, and the spermatozoa were examined using both light and electron microscopy. The degree of motility was also noted by Kalla et al. Ejaculated spermatoza were immotile 90 days after GAA treatment, but little evidence for any abnormality in the spermatozoa could be seen by light microscopy. Some ultrastructural changes were observed, but not to the extent previously reported in spermatozoa of Macaca fascicularis. After termination of treatment, semen samples were obtained every 5th day until sperm count and motility recovered to the normal level. After 90 days only a small proportion of spermatozoa showed abnormal structure. We conclude that in a subhuman animal model gossypol induced effects on sperm motility and morphology are reversible.

Involvement of prostaglandin in the antifertility effects of gossypol

This study was undertaken to determine the effects of gossypol alone and gossypol in combination with prostaglandin and aspirin. Rats were administered gossypol (40 mg/kg/day), gossypol and prostaglandin (PGF2 alpha-2 mg/kg/day), gossypol and aspirin (300 mg/kg) for 4 weeks. A marked effect of the gossypol-prostaglandin combination was observed on sperm motility and spermatogenesis. The effect of the gossypol-aspirin combination was less pronounced. The ratio of body weight to testicular and epididymal weights between the different groups showed no marked difference. No effect of drug treatment on plasma testosterone, LH and FSH was observed. The data presented in this paper suggest that prostaglandin plays an important role in the antifertility effects of gossypol.

Studies on the male antifertility agent gossypol acetic acid. VII. Effect of motility stimulated factors on the revival of human spermatozoal motility after gossypol treatment in vitro

Human spermatozoa were incubated with gossypol acetic acid (100 micrograms/1 X 10(6) spermatozoa/ml) at 37 degrees C for 30 min. The drug treatment inhibited the spermatozoal motility significantly. Washing of the spermatozoa, after gossypol treatment, did not effect their motility. A partial revival in the motility of the spermatozoa was observed when gossypol treated spermatozoa were incubated, after washing, with motility stimulating factors, e.g. theophylline, dibutyryl-cAMP and Kallikrein.

Effect of gossypol on immature male rats

In immature male rats the body growth rate, the testis and epididymis weight were not affected by gossypol treatment (4, 8 and 40 mg/kg body weight/24 hrs. for 30 days). There was however a marked reduction in the weight of the prostate after high dose gossypol administration. Furthermore gossypol treatment did not show any effect on the histoarchitecture of the testis nor did the drug treatment have any effect on sperm motility. The plasma levels of testosterone, LH and FSH in gossypol treated animals were no different from those on the controls.

Effect of gossypol on bull spermatozoa in vitro

Gossypol acetic acid in a concentration of 1,000 microgram/ml solvent is able to immobilize 1 ml of native bull semen (sperm concentration: 8.5 X 10(8)/ml; motility rate: 87.4%) within 30 min. After GAA treatment the spermatozoa show severe morphological damage on the membrane system, on the acrosomal complex and on the tubular complex of the end piece. The working mechanism of GAA can be assumed to be inactivation of enzyme activities or in direct reactions with plasma membrane material.

Studies on the male antifertility agent gossypol acetic acid. VI. Effect of gossypol acetic acid on the fertility of bonnet monkey. Macaca radiata

Gossypol acetic acid (4 mg/day/5 days a week) suspended in Tonoferon tonic was given to male bonnet monkeys, Macaca radiata, by oral route for 3 months. Marked reduction in the sperm count/ejaculate and sperm motility were observed after gossypol treatment; both motility and sperm count/ejaculate returned to the normal level 8-10 weeks after termination of gossypol treatment. The citric acid and fructose levels in the semen of gossypol treated monkeys were not different from those of the controls.

Effect of cyproterone acetate on testis and accessory sex organs of male rat

A significant reduction in testis, epididymis, seminal vesicles, prostate, and adrenal weight of adult rats was observed after CA treatment (10 mg/animal/day) for 13, 26 and 39 days. Biochemical assay on the epididymis showed a fall in the activities of acid and alkaline phosphatase. A significant fall in citric acid content of seminal vesicle and prostate in experimental animals was noted after CA treatment. Histoarchitecture of accessory sex organs was severely impaired.

Effect of gossypol on testicular testosterone production in vitro

Testicular minces were utilized to study the effect of gossypol on testosterone production. Testosterone production was assessed in both control nd gossypol treated groups after 0 to 4 hours incubation in the presence of hCG. Media testosterone was measured by radioimmunoassay. Gossypol did not alter testosterone production when present in incubates at the concentrations of 3.5 x 10(-5) M, 7 x 10(-5) M and 3.5 x 10(-4) M. Preincubation of testis mince with gossypol (7 x 10(-6) M, 7 x 10(-5) M, 3.5 x 10(-4) M) for 1 to 4 hours did not alter subsequent hCG induced testosterone production in mature rats. Testosterone production however, was inhibited in immature rat testis when the whole testis was incubated for 4 hours with different concentrations of gossypol (7 x 10(-6) M, 7 x 10(-5) M, 3.5 x 10(-4) M). In vivo testosterone production was not inhibited in the immature rat testis 24 hours after oral administration of gossypol (100 mg/kg).

Biochemical analysis of rat testis and epididymis after cyproterone acetate treatment

Male rats were treated with cyproterone acetate (10 mg/day/rat) for 13, 26 and 39 days. A marked decrease in proteins, nucleic acid and phospholipid content was recorded in testis and epididymis after CA treatment. However, a significant increase in glycogen and cholesterol content in testis and epididymis was observed after CA treatment.

Studies on the male antifertility agent--gossypol acetic acid. V. Effect of gossypol acetic acid on the fertility of male rats

Gossypol acetic acid was given to male rats at a dose of 7.5 mg/rat/day six days a week for ten weeks. After nine weeks of gossypol treatment no implantation sites were observed in the females mated with gossypol treated males. After ten weeks of gossypol treatment all the spermatozoa in the vas deferens were non-motile. Gossypol treatment did not affect the body weight and the weights of the accessory sex organs. Plasma LH and FSH levels, hCG binding in testis and succinic dehydrogenase (SDH) and adenosine triphosphatase (ATPase) activities in liver, kidney and testis were not affected by gossypol treatment. Histological observations of the testis revealed partial damage to the seminiferous tubules. Single high doses of gossypol did not induce significant changes in the body weight and weights of testis and accessory sex organs. ATPase activity in the testis was reduced significantly after gossypol treatment, the enzyme activity in liver and kidney, was however, affected at high doses only. Gossypol treatment had no effect on the histoarchitecture of the testis. Intratesticular administration of gossypol evoked localized damage in the testis. Gossypol treatment had no effect on I125 FSH binding to the rat testis homogenate in vitro.

Presence of luteinizing hormone receptor binding inhibitor (LH-RBI) in ovine testis

Luteinizing hormone receptor binding inhibitor (LH-RBI has been isolated from the aqueous extracts of ram testis using Sephadex column chromatography. Sephadex G-75 fraction I was found to inhibit the binding of I125 LH to rat testis receptors. Further purification of Sephadex G-75-I fraction on G-200 column gave four fractions (I-IV), the maximum inhibitory activity to inhibit I125 LH binding to rat testis receptor was associated with the fraction I only. Fraction II gave marginal inhibition only, whereas fractions III and IV did not have any inhibitory effect on I125 LH binding to rat testis receptors. Our findings suggest that LH-RBI isolated from ram testis is a protein having molecular weight more than 10,000 Daltons.

Studies on the male antifertility agent--gossypol acetic acid. III. Effect of gossypol acetic acid on rat testis

Gossypol acetic acid at the dose of 5 mg/rat/day for 2 and 4 weeks did not cause any significant effect on the body weight, testis, epididymis, seminal vesicle and prostate weight, nor gossypol treatment had any significant effect on the activities of acid phosphatase and succinic dehydrogenase in the testis. Changes in the testis ATPase activity were, however, significant after gossypol treatment. During the course of present investigations no effect of gossypol treatment on 3H thymidine incorporation into DNA of testicular cells was observed, nor there were any changes in the DNA and total protein content of the testis after gossypol treatment. Gossypol treatment did not cause any effect on the plasma Na+ level. However, transient decrease in the plasma K+ level was observed; decrease in K+ level two weeks after gossypol treatment was restored to normal after 4 weeks of gossypol treatment. No changes in the histology of the testis were observed 2 weeks after gossypol treatment but marked inhibition of spermatogenesis was observed 4 weeks after gossypol treatment. Motility of vas deferens spermatozoa was also markedly inhibited 4 weeks after gossypol treatment. In the light of the present observations and those of others, there is a clear demonstration that gossypol acts directly on the spermatozoa and on the testis; at both the sites the drug interferes in the ATPase activity.

Studies on the male antifertility agent-gossypol acetic acid. II. Effect of gossypol acetic acid on the motility and ATPase activity of human spermatozoa

A marked reduction in the motility of the human spermatozoa was observed when spermatozoa were incubated with 10 and 100 microgram of gossypol acetic acid for different time period at 37 degrees C; the motility was reduced from 83% to 4% after 210 minutes (P less than 0.001). A significant decrease in the activities of Ca++ and Mg++ activated ATPase in the spermatozoa was observed after gossypol treatment (P less than 0.005). Changes in the zinc++ concentration in the spermatozoa after gossypol treatment were, however, not significant. The present investigations suggest that inhibition of the sperm motility after gossypol treatment may be due to the inhibition of the ATPase activity in the spermatozoa.

Studies on the mechanism of action of alpha-monochlorohydrin

After a single oral dose of 100 mg/kg of alpha-chlorohydrine, two distinct phases in the response of the testes to the treatment have been observed: (i) the immediate onset of testicular swelling lasting up to five days, accompanied with a steady increase in the weight of the testes and (ii) thereafter a constant decrease in the testes weight. Changes in the diameter of the seminiferous tubules and the thickness of the basement membrane were observed after the administration of the drug. Multinucleated giant cells were encountered 5 days after drug administration. Alkaline phosphatase, SDH, nucleic acids and proteins showed a fall after treatment with the drug. On the contrary, cholesterol, phospholipids and glycogen showed an increase after its administration. Acid phosphatase showed a fall in the initial stages only, but the activity was higher after 10, 20 and 40 days of the treatment with the drug. The level of plasma and testes testosterone remained normal after chlorohydrin administration. The induction of lesions in hypophysectomised gonadotropin-stimulated animals suggests that the action of chlorohydrin is not mediated through gonadotropins. Alpha-chlorohydrin administered intratesticularly did not evoke any changes in the histo-architecture of the testis.

Response of scrotal and non-scrotal vertebrate testis to the male antifertility agent alpha-chlorohydrin

Effect of single oral dose (90 mg/kg body weight), multiple doses (90 mg/kg body weight for 7 days) or even higher doses (180-300 mg/kg body weight) of alpha-chlorohydrin on the testis-epididymis complex of dog, rat, cryptorchid rat, hedgehog, domestic fowl, lizard, frog, and toad has been studied. alpha-chlorohydrin treatment, at any dose, did not induce lesions in the testis-epididymis complex of dog and hedgehog having testis in scrotum and inguinal canal respectively. Abdominal testis of cryptorchid rat, domestic fowl, lizard, frog and toad also did not respond to alpha-chlorohydrin treatment. Lesions in normal rat testis-epididymis complex, after single oral dose of alpha-chlorohydrin, were quite prominent. Non-sensitivity of alpha-chlorohydrin to these animal species may be due to the absence of the pampiniform plexus complex in hedgehog and sub-mammalian animal species. Absence of conventional epididymis in the sub-mammalian animal species may be the additional reason of the non-sensitivity of the drug. Prominence of collateral blood vasculature in dog testis-epididymis complex and some alterations in the blood supply due to cryptorchidity in cryptorchid rat testis seems to be the reason of non-sensitivity of alpha-chlorohydrin to dog and cryptorchid rat testis. These observations confirm the hypothesis that the action of a single oral dose of alpha-chlorohydrin is associted with the blood vasculature of the testis-epididymis complex.