pharmacokinetic, toxicological and clinical studies on protodioscin
I. Viktorov, E. Bozadjieva, M. Protich, et al.
Higher Medical Institute; Medical Academy Institute of Endocrinology,
Gerontology and Geriatrics; Medical Academy Institute of Obstetrics
and Gynecology, Bulgaria
IIMS Therapeutic Focus (1994)
Clinical investigations on a total of 212 males with disorders of
sexual functions confirmed experimental data pointing at a pronounced
stimulating effect on these sexual functions by the new phytochemical
preparation of Tribulus terrestris extract. Administered in average
daily doses of 1.5 g in the course of 30 to 40 days, it restores
and improves libido sexualis in all forms of impotentia coeundi.
Studies on the acute, subchronic and chronic toxicities of protodioscin,
the active ingredient of Tribulus terrestris extract, determined
that the compound is to be classified as practically non-toxic substances.
The harmlessness of the preparation deserves particular attention.
No data about toxic manifestations were established under experimental
conditions with acute, subchronic and chronic toxicities (behavioral,
hematological, biochemical, functional and morphological studies).
No data were established concerning carcinogenic and teratogenic
The combined action of the preparation (stimulation of the sexual
behavior and spermatogenesis) and the absence of adverse effects
characterize the preparation as an original agent for the treatment
of males with disorders in the sexual functions.
The problem of stimulation of sexual function, and of spermatogenesis
and ovogenesis in particular, is both of biological and medical
significance, as it is associated with the problem of preservation
of the sexual potential of male and female individuals. According
to statistical data, 10 - 20% of all marriages are childless. In
about 30 - 50% of the cases, male sterility is the cause. The diagnostics
and treatment of male sterility is still a very difficult task.
At present, drugs on hormonal basis are predominantly used in the
treatment of hypogonadism and genital anomalies. In fact, the substitutive
hormonal therapy is sometimes ineffective and quite often it induces
a lasting hypofunction of the hypothalamic-pituitary-gonadal axis.
Therefore, regardless of the great number of new, highly effective
and possibly less harmful drugs, studies in this field are very
topical. The formulation of a non-hormonal preparation with sufficient
activity and without harmful side effects, could contribute to overcoming
of the therapeutic problems in the sphere of sexual functional disorders.
The plant Tribulus terrestris L., has long been known in folk medicine
of Eastern countries and Bulgaria and has been used in the treatment
of sexual deficiency. The present article is intended to acquaint
the reader with the pharmacological, toxicological and clinical-therapeutic
characteristics of the phytochemical preparation, marketed under
the name Libilov and Tribestan®.
The active components of the plant Tribulus terrestris L. extract
are non-steroid saponins of the furostanol type, termed protodioscin.
A pronounced stimulating effect on the spermatogenesis is observed
after the preparation is administered orally to sexually mature
Increased numbers of spermatogonia, spermatocytes, spermatids and
mature spermatozoa in the testes has been observed without widening
of the diameter of the seminiferous tubules. In parallel, increased
number of Sertoli cells is observed in a volume unit from rat testes.
Oral administration stimulates the mitotic activity of spermatogonia
in mature rats. Oral administration of the preparation leads to
intensification of spermatogenesis and enhancement of the quality
of spermatozoa in sexually mature rats. The percentage of motile
spermatozoa increases, the characteristics of their motility improve,
prolonging the period of their viability at the same time. Given
orally to swine, protodioscin stimulates their sexual behavior.
The clinical trials of the preparation have also confirmed the experimental
Protodioscin, administered to male subjects with disorders in the
spermiogram, due to varicocele, increases the volume of ejaculated
sperm by 1-2 ml, increases spermatozoid concentration by 30 million/ml,
increases the percentage of motile spermatozoa by 30%. The preparation
has a marked effect on the motility of spermatozoa in case of oligoasthenozoospermia,
as revealed by the study of its therapeutic properties in men. The
mean number of motile spermatozoa in the group studied was 29% prior
to the study, and later it reached up to 36.6%. The motility rate
of the spermatozoa prior to the treatment was 1.95 mm/sec and 3.76
mm/sec post treatment.
Of definite interest is the treatment of patients with unilateral
and bilateral hypotrophy of the testes, combined with disorders
of the spermiogram. The libido was enhanced after a 60-day protodioscin
treatment and the characteristics of the spermiogram were improved.
Recovery and enhanced libido were observed in patients with primary
and secondary hypogonadism after administration, as well as prolonged
Both experimental and clinical studies reveal that protodioscin
is not toxic and induces no adverse effects.
CHEMICAL AND PHYSICAL
Protodioscin is yellow-brown amorphous powder with a specific aroma
and bitter taste; soluble in water, sparingly soluble in methyl
alcohol and insoluble in chloroform.
the stimulating effect on spermatogenesis
Spermatogenesis is a complicated process, covering proliferation
of the spermatogonia, long-lasting process of the tissue meiosis
and numerous changes in the spermatids during their preformation.
The effect on the sexual cells can occur during the reproductive
period - mitotic division of the spermatogonia or during the maturation
of the spermatozoa. The effect on protodioscin on mitosis and maturation
of the gonocytes has been studied using quantitative cytological
methods. After oral administration of protodioscin in a single daily
dose of 70 mg/kg body mass for 20 days, the testes of 8 rats were
fixed in neutral formol-calcium and in Serra's solution, and later
embedded in paraffin. The testes of 8 untreated animals were used
as the control. The histological preparations from the testes were
stained with hematoxylin (after Mayer) and fast-green (after Yordanov,
1976). Spermatogonia, spermatocytes and spermatids of 40 cross-sections
through the seminiferous tubules were counted for each animal from
both experimental and control groups (a total of 640), with identical
diameter of the tubules (determined by eyepiece micrometer) in phase
VII, according to the classification of Leblond and Clermon (1952).
Using light microscopy, the thickening of the layer of the spermatogenesis
cells was observed in the cross-sections of the seminiferous tubules
and a narrowing of their lumen in the treated animals (Fig 1). That
resulted from the increased number of rows of sexual cells. The
number of spermatogonia in the 8 experimental animals (i.e. in 320
sections of the seminiferous tubules) was 58 spermatogonia on the
average per seminiferous tubule (between 48 and 63). The number
of spermatogonia in one seminiferous tubule in the control animals
was 36 (between 36 and 40 spermatogonia per tubule). The mean number
of spermatocytes in a seminiferous tubules was identical to that
of the spermatogonia. The number of spermatids in phase VII varied
from 148 to 180 per seminiferous tubule in the treated animals (mean
value 176). Their number in the control animals was between 112
and 125 (mean 119). The preparation significantly increased the
number of spermatogonia, spermatocytes and spermatids in the testes
of rats, with no other effect on the diameter of the seminiferous
Figure 1. Stimulation of spermatogenesis by protodioscin
Effect on DNA synthesis in gonocytes
The preparation's effect on DNA synthesis in the sexual cells has
been studied by cytohistoradiography. The testes of rats treated
with protodioscin (for 7 days) and with 3H-thymidine (every second
day), and later with colchicine (3 hours prior to decapitation),
were fixed in Serra's solution and embedded in paraffin. The sections
were covered with Ilford liquid emulsion and left to stay for 25
days. A higher number of 3H-thymidine-labelled spermatogonia type
"A" and "B" was found in the treated rats compared to the control
animals (Fig. 2)
Figure 2. Effect of protodioscin on DNA synthesis.
The percentage of
3H-thymidine-labelled spermatogonia vs. total number
The mean number of spermatogonia per section from the seminiferous
tubules was 56 in the treated animals, 41 of them labeled with radioisotopes.
These numbers were 50 and 18 respectively, in the control animals.
The increased number of spermatogonia, with 3H-thymidine included
for the treated animals, suggested an intensified DNA synthesis
under the effect of protodioscin, as well as an increased number
of spermatogonia during the phase V of the cell cycle.
Effect on Leydig and
Sertoli cells in the testes
It is well known that Leydig and Sertoli cells participate in the
process of spermatogenesis. Quantitative cytological methods were
used for the evaluation of the effect of the protodioscin on these
cells. The results show that the number of Sertoli cells was increased
in the seminiferous tubules of protodioscin-treated animals, compared
to the controls (Fig. 3).
Figure 3. Effect of protodioscin on Leydig and
The mean number of Sertoli cells in a section of the seminiferous
tubule in the treated animals was 29 versus 19.50 in the controls
(increase by 40%). The cytological studies of the testes showed
no differences in the number of Leydig cells between the experimental
and control animals.
Effect on concentration,
motility and survival of spermatozoa
The concentration, motility and viability of spermatozoa in the
epididymis of rats treated for 30 days with protodioscin were studied
immediately after decapitation. Sodium citrate was used as diluent.
The mean spermatozoa number per ml was higher by two million in
the treated animals, compared to the controls (Fig. 4).
Figure 4. Effect of protodioscin on the concentration
and motility of rat spermatozoa.
The number of motile spermatozoa under the microscope was 8% higher
in the treated animals. Furthermore, their spermatozoa were more
viable. The loss of their advancing movements could be observed
on the 75th minute, on the average, and in the control animal group
- by the 45th minute (Fig. 5).
Figure 5. The effect of protodioscin on the viability
of rat spermatozoa.
Effect on the sexual
The effect of protodioscin on the sexual behavior was studied on
male pigs with confirmed lasting impotence. The preparation was
administered orally and its effect on the sexual behavior and sexual
reflexes was followed up daily. Individual animal reaction to the
preparation was observed. The libido and sexual reflexes were restored
in 71% of the animals with complete absence of libido, treated with
a daily dose of 70 mg/kg for 10 days. In the animals with poor libido
and long reflex period of sexual reflexes, recovery was recorded
in 100% of the cases (Fig. 6).
Figure 6. Effect of protodioscin on animal libido.
Studies on serum concentration
of the hormones from the hypophyseal-gonadal axis
The experiments were carried out on healthy subjects (8 male and
8 female), aged between 28 and 45 years (Milanov et al., 1981).
The preparation was administered orally in a dose of one tablet,
three times daily at 8-hour intervals for 5 days. The basal hormonal
levels were determined before and after the intake of the protodioscin
(at 8:00 am and at noon). The concentrations of the luteinizing
(LH) and follicle-stimulating (FSH) hormones were determined by
kits provided by Biodata (Italy). Serum testosterone was determined
by the method of R.H.Williams (1967), serum estradiol - by the method
of C.P.Orezyk (1974), using kits provided by the Sorin (Belgium).
The results reveal that the drug elevated the level of the luteinizing
hormone and testosterone in the orally treated healthy males, not
affecting FSH (Fig. 7A).
In the females, the concentration of FSH and estradiol were increased
under the effect of protodioscin, whereas the testosterone concentration
was not significantly changed (Fig. 7B). The results show that the
preparation has an effect on the hormones from the hypophyseal-gonadal
axis, while at the same time not disturbing the hormonal balance
in the body, thus enabling its administration as an agent stimulating
the reproductive function.
Figure 7. Effect of protodioscin on the concentration
of hormones in the hypophyseal-gonadal axis in the blood plasma
of healthy males (A) and females (B).
Effect on the central
The screening system for neuro-pharmacological tests (R.Nikolov,
1980) was used in the studies. The following parameters of the treated
animals were observed during the first stage of the screening: awareness,
mood, motor activity, muscle tone and somatic reflexes.
The second stage of the screening covered the administration of
many substances with an effect on the central nervous system, e.g.
corazol, strychnine, nicotine, arecoline, phenamine, sodium hexobarbital,
reserpine. The drug was applied intraperiotoneally to albino mice,
H line, with a body mass of 18 - 22 g.
With a dose of 100 mg/kg body mass (1/4 of LD50), the drug had no
effect on the behavior of the contact animals in the cage. During
observations out of the cage, the animals became more excited, with
enhanced reactivity. Their muscle tone was simultaneously reduced.
In that dose, the drug inhibited moderately the corazol-induced
convulsions, but the other reflexes were suppressed. The maximum
tolerance dose - 300 mg/kg body mass - led to reduction of the motor
activity, slight disturbance of gait and lower muscle tone of the
limbs and stomach.
Effect on the cardiovascular
The effect of the drug on the blood pressure values of cats under
urethan narcosis was studied by the method of Ludwig Zyon (S.Vankov,
1981). The drug was injected intramuscularly and intraperitoneally
as 10% aqueous solution. The intramuscular application of the drug
in doses of 50, 100 and 150 mg/kg body mass had no significant effect
on the blood pressure of the urethanized cats. A significant hypotensive
effect was observed with the intraperitoneal application of the
drug in a dose of 150 mg/kg body weight, advancing from the 5th
to the 10th minute after application. The values of the arterial
pressure decreased by 20% compared to the initial ones. The oral
administration of protodioscin in a dose of 150 mg/kg on awake dogs
had no effect on the blood pressure. The oral administration in
doses of 50, 100 and 150 mg/kg body mass had no effect on the autonomic
nervous system of the urethanized cats.
The experiments were carried out on albino, Wistar rats (180 - 200
g body mass) in 1981 by N. Dikova and V.Ognianova. The unchanged
protodioscin in plasma, bile and urine was measured by thin-layer
chromatography. Semi-quantitative measures were recorded and standardized
by the precisely determined protodioscin concentrations. To determine
the concentration of plasma protodioscin, the animals were intravenously
injected with single doses of 50 and 200 mg/kg body mass. Citrate
blood was withdrawn 2, 4, 10, 20, 30, 45, 60, 90, 120 and 180 min.
after injection. To determine protodioscin excretion in the bile
the animals were treated intravenously and orally with single doses
of 50 and 200 mg/kg.
The bile was dynamically collected: up to the 6th hour, from the
6th to the 9th hour, from the 9th to the 24th hour after each application.
Twenty-four-hour urine was collected. The results show that protodioscin
was rapidly eliminated from the plasma and its concentrations were
insignificant after the 180th minute. About 12 to 14% protodioscin
were excreted in the bile and about 6 - 7 % in the urine within
24 hours after the intravenous administration of the doses of 50
and 200 mg/kg. Protodioscin from 2 to 4% were excreted with the
bile after oral administration. No measurable concentration of unchanged
protodioscin was found in 24-hour urine after oral administration.
(G.Tanev, S.Zarkova, 1980)
The acute toxicity of protodioscin was studied after intraperitoneal
and oral application to albino mice, H line (18 - 20 mg body mass)
and albino rats (160 - 180 g body mass). LD50 was also studied.
It was concluded that the product can be included in the group of
practically nontoxic substances. LD50 was 1942 mg/kg body mass with
intraperitoneal application to mice and over 10,000 mg/kg body mass
- with oral administration. The mean lethal dose of protodioscin
with intraperitoneal application to rats was 750 (375 +/- 1,500
) mg body mass, and after oral administration - over 10,000 mg/kg.
The protodioscin was administered orally to albino Wistar rats for
30 and 90 days in the following doses: 75 mg/kg, 150 mg/kg, 225
mg/kg and 300 mg/kg body mass. No increased lethality was observed,
nor a change in the behavior of the animals. No significant changes
were observed in the routine clinical-laboratory and biochemical
indices, nor morphological changes in the internal organs.
Protodioscin was administered orally to albino rats for 6 months
in doses of 75 mg/kg and 150 mg/kg body mass, as well as in 75 mg/kg
body mass for 180 days to beagle dogs. The following toxic symptoms
were looked for: changes in behavior, changes in the hematological,
biochemical, functional and morphological parameters. No significant
changes were found both in the behavior and in the reflexes of the
animals. No increased lethality was observed. No pathological deviations
from the physiological values were found in all hematological and
clinical-chemical indices studied. No pathological changes in the
structure of the internal organs, related to the toxic effect of
the preparation, were detected.
Teratological and embryotoxic studies were simultaneously performed,
as well as some experiments to follow the pre- and postnatal development
No teratogenic and embryotoxic action, nor deleterious effect on
the development of the first generation after its littering, were
found after the oral administration of the product in a dose of
750 mg/kg body mass to pregnant Wistar rats.
Studies were carried out to exclude the possible carcinogenic potential
of protodioscin during a long-term treatment of rats (Gendzhev,
Increased incidence of neoplasms compared to the control animals
was not observed with daily doses of 50 and 150 mg/kg body weight,
administered orally for 23 months. No toxic damage was found morphologically
in the rat organs.
DISCUSSION OF THE RESULTS
The experimental data on the biological activity of protodioscin
show that its oral administration to rats significantly increased
the number of spermatogonia, spermatocytes and spermatids, without
any changes in the diameter of the seminiferous tubules. This fact
is associated with the confirmed stimulating effect on spermatogenesis
as a whole. It is well known that DNA synthesis occurs in the s-phase
of the mitotic cycle. A fact of certain interest is that a significant
increase of type A and B spermatogonia was found in the rats simultaneously
treated with protodioscin and 3H-thymidine during the s-phase.
Hence, it can be concluded that the product intensifies the mitotic
activity of spermatogonia. The cytologically detected increased
incidence of Sertoli cells, caused by the product, presupposes that
the mitosis of these cells has also been stimulated. The important
role of Sertoli cells in the regulation of spermatogenesis is well
known (Lacy, 1967; Kerr and Klester, 1974, Steinberger, 1971), hence
the increased number of Sertoli cells during protodioscin treatment
should be associated with the intensification of spermatogenesis.
No changes were identified in the Leydig cells of the experimental
animals, which suggests that the effect of the product on the spermatogenesis
probably does not include these cells. The literature data show
that the proliferation of spermatogonia in mammals and birds is
FSH-stimulated (Stoinberger et al., 1964; Mancini et al., 1966;
Ishiis and Furua, 1975; Krueger et al., 1974). The authors presume
that the effect of FSH on spermatogenesis is due to Sertoli cells.
The radioimmunological studies on healthy males showed no changes
in the FSH-level under protodioscin effect, which suggests presence
of a selective effect of the product on gonocytes. On the other
hand, elevated LH-levels were found in protodioscin treated healthy
males, which suggests the existence of central action.
The pharmacokinetic studies reveal no measurable concentrations
of the product in the plasma after oral administration to rats,
but spots unidentified so far were detected by the chromatographic
The authors (Dikova and Ognyanova) presume a biotransformation of
the product in the body. In such cases, some of the metabolites
formed during the biotransformation can be expected to possess a
stimulating effect at hypothalamic level.
The effect on the libido of the male pigs is clearly manifested.
Protodioscin not only stimulates the libido, but also possesses
a therapeutic effect as well in the cases of impotence, manifested
in complete absence of libido. The effect of the product on the
quality of the spermatozoa clearly shows that the spermatozoa of
the treated animals are more viable and more resistant, suggesting
a better fertility. Many researchers believe that the sexual behavior
of the animals and the motility of the spermatozoa depend on testosterone
levels. Other authors think that the sexual behavior is modulated
by dihydrotestosterone. The problem of the mode of modulation of
the sexual behavior remains debatable. If we assume that androgen-like
factors are formed through biotransformation in the body, they would
not induce changes in the interstitial cells.
Special attention should be paid to the harmlessness of the product.
No evidence of acute, subacute and chronic toxicity has been found
during the experimental behavioral, hematological, functional, biochemical
and morphological studies. No data on carcinogenic and teratogenic
effect are available.
The fact that the product has an effect on the hormonal balance
in the body, without disordering its regulatory mechanisms, is of
equal importance. The combined action of the drug (stimulation of
sexual libido and spermatogenesis) and the absence of adverse effects,
characterize it as an original agent for the treatment of males
with disordered sexual function.
Materials and methods
The experimental data from protodioscin administration have been
clinically confirmed so far by three groups of researchers: by the
Higher Military Medical Institute under the guidance of Prof. I.
Viktorov, Corresponding Member of the Bulgarian Academy of Sciences;
by the Medical University of Sofia; State University Hospital of
Endocrinology, Gerontology and Geriatry, under the guidance of Prof.
E. Bozadzhieva, and by the National Institute of Obstetrics and
Gynecology - under the guidance of Prof. M. Protich.
The studies were carried on 212 male individuals, aged between 14
and 60 years. The therapeutic properties of protodioscin were studied
in patients with partial or complete impotence. Both the tolerance
and the adverse effects of the product were studied. The studies
were carried out by the method of simple blind experiment, using
placebo. In nozological terms, the studies covered various types
of male impotence: idiopathic oligoasthenozoospermia - 39 patients,
resection of the left internal testicular vein in varicocele, with
subsequent oligoasthenozoospermia - 50 patients; inflammatory process
of the prostate with oligo- and azoospermia - 53 patients, primary
and secondary male hypogonadism - 20 patients, impotentia coeundi
- 50 patients. The product was individually administered to all
patients who had not received hormonal agents for at least one month
prior to the treatment. The duration of the treatment depended on
acuteness of the disease - 30 - 60 days on the average (Bozadzhieva
et al., and Protich et al.) and 90 days (Victorov et al.) the mean
daily dose was 3 - 6 film tablets of 0.250g. Some of the patients
were favorably affected by 3 tablets daily (Protich et al.), whereas
the other research teams administered 6 tablets (3 x 2). The andrological
state was used as the basis for the adequate evaluation of the reproductivity
of the patients by all three teams. The basic parameters of sperm
were observed, i.e. volume and pH of the ejaculate, concentration
of spermatozoa (number/ml), percentage of motile spermatozoa, mean
rate of population motility and percentage of pathological forms
of the spermatozoa. Detailed case history on the sexual behavior
of the patients was recorded prior to and after the therapeutic
protodioscin course. The effect of the product on hair growth was
observed in some patients. One of the teams (Bozadzhieva et al.)
also observed the changes in the serum levels of gonadotropins,
progesterone, testosterone, estradiol and cholesterol. The other
team (Victorov et al.) followed up the changes in testosterone serum
levels in the protodioscin treated patients. The hormonal levels
were radioimmunologically determined using kits and reagents provided
by the French-Italian-Belgian Association CEA-IRE-SORIN. The results
from these studies were statistically assessed by variation analysis.
Significant changes in spermatozoon motility were found after protodioscin
intake for 60 days (with a daily dose of 3 film tablets) by males
with idiopathic oligoasthenozoospermia. The number of spermatozoa
with normal motility, as well as the mean motility rate, were increased.
The percentage of the motile spermatozoa was 29, on the average,
prior to the treatment and reached up to 36.66 after the treatment
(p < 0.005). The mean motility rate of spermatozoa prior to the
treatment was 1.95 mm/sec, after the treatment - 3.63 respectively
(p < 0.001). No changes were observed in the ejaculate volume (Fig.
8). In both cases (before and after treatment) the ejaculate volume
was within the limits of the norm, about 4 ml on the average. The
number of spermatozoa in the treated patients was higher by 3 ml
per ml of ejaculate on the average. In some cases, normalization
of the spermiogram occurred during repeated treatment with a daily
dose of 6 tablets. In these cases, the improvement of the spermiogram
(normalization of the increased viscosity, increased ejaculate volume,
increased concentration and accelerated motility of the spermatozoa)
was accompanied be elevation of the serum levels of the luteinizing
hormone and testosterone, and reduction of the estradiol level.
Figure 8. Effect of protodioscin treatment on spermatozoa
concentration and motility.
The patients with idiopathic azoospermia after 90-day treatment
with a daily dose of 1.5g are of particular interest. The results
were significant in three of all 7 patients treated. No spermatozoa
were detected prior to the treatment. After the treatment, 3.5 million/ml
ejaculate were recorded in one of the patients, 15 million/ml in
the second and 28 million/ml in the third. The percentage of motile
spermatozoa in the first patient was 10, and in the other two -
between 25 and 30. The motility rate of the spermatozoa was about
5 mm/sec. In two of the patients, 30 - 40 spermatozoa per field
were observed, and in the third - about 5 spermatozoa per field
after the treatment, compared with the absence of any prior to the
treatment (Fig. 9).
Figure 9. Effect of protodioscin on patients with
One of the patients failed to be affected by the product. The studies
on the patients from that nozological group continued with the administration
of maintenance dose.
The clinical comparison of the results from the treatment with provirone
of patients with idiopathic azoospermia and after protodioscin administration
revealed a favorable effect on three of the patients (out of 6),
unsuccessfully treated with provirone for a long period of time.
The results in the patients with varicocele and oligoasthenozoospermia
as regards the motility of the spermatozoa were identical in the
reports of all research teams, regardless of the differences in
the doses and duration of the treatment. Protich et al. found an
average of 26.88% motile spermatozoa prior to the treatment and
after a 60-day course with a dose of 1 tablet, three times daily
- 39% (p < 0.02) with a mean motility rate of spermatozoa 2.06 mm/sec
prior to the treatment and 4.44 mm/sec post treatment respectively
(Fig. 10). No change in the ejaculate volume was found. The other
team (Victorov at al.) observed more pronounced changes in the ejaculate
volume after the 90-day treatment with a daily dose of 1.5 g (4.5
ml compared to 1 - 2 ml prior to the treatment, i.e. an average
of 1.55 ml of ejaculate volume in all patients). The number of spermatozoa
in 1 ml reached the values in 100% of the patients treated. The
mean percentage of motile spermatozoa prior to the treatment was
2.06 and was increased to 33.09 (Tables 1,2,3).
Figure 10. Effect of protodioscin in patients with
varicocele and oligoasthenozoospermia.
|| Before treatment
|| After treatment
| Concentration of spermatozoa, millions/ml
| Motility, %
| Motility rate, mm/sec
Table 1. Results of protodioscin treatment (1
tablet 3 times daily for 60 days) of 38 males with idiopathic oligozoospermia
(represented in mean values).
|| Before treatment
|| After treatment
| Concentration of spermatozoa, millions/ml
| Motility, %
| Motility rate, mm/sec
Table 2. Results of protodioscin treatment (1
tablet 3 times daily for 60 days) of 16 males after varicocele operation
with existing oligoasthenozoospermia.
|| Before treatment
|| After treatment
| Concentration of spermatozoa, millions/ml
| Motility, %
| Motility rate, mm/sec
Table 3. Results of protodioscin treatment (2
tablets 3 times daily for 90 days) of 36 males after varicocele operation
and existing oligoasthenozoospermia.
*These data are statistically significant.
The results of protodioscin administration to patients with unilateral
or bilateral hypotrophy of the testes and azoospermia deserve particular
attention. The patients complained of a sense of heaviness and distention,
as well as of a slight pain in the testes between 40th and 60th day
after the start of the treatment with a daily dose of 6 tablets. Upon
examination, a slight pain in the testes occurred upon palpation,
as well as a slight swelling, with no other evidence of pathological
changes. Improvement both as regards to the ejaculate volume and the
concentration and motility of the spermatozoa was observed towards
the end of the treatment. The testosterone serum level was elevated
from 1.75 mg/ml to 3.75 mg/ml. The pain in the testicular region upon
palpation abated within 2 - 3 months after treatment. Protodioscin
administration to patients with chronic inflammatory process of the
prostate and disorders in the spermiogram led to insignificant changes
in these cases when the inflammatory process had been treated previously.
No changes were found in patients with chronic inflammation of the
prostate (not treated previously). Out of 14 patients with reduced
libido and absence of pathology in the male genital organs, treated
for 30-days (daily dose - 2 tablets, three times), 12 manifested obvious
improvement of the libido, one patient - a slight improvement (after
a 60-day treatment cycle) and no effect was observed in another one.
Out of a total of 36 patients with chronic prostatitis and reduced
libido, 15 were very favorably affected by the end of the treatment
cycle (a total dose of 90 - 100 g), 12 - favorably, and in 9 of the
cases with a duration of the inflammatory process over 5 years, no
effect occurred. The patients with hypotrophy of the testes and idiopathic
azoospermia had no complaints as regards to the libido, but in the
course of the treatment aimed at improving the spermiogram an apparent
libido enhancement was recorded. Out of 9 patients treated for one
of the gravest forms of male hypogonadism (Klinefelter's syndrome,
due to chromosomal anomalies), the libido was enhanced in three of
the patients, erection was reported in two and sexual intercourse
and masturbation were reported in another two patients. Elevated levels
of luteinizing hormone after the treatment were found in these patients.
The levels of the remaining sexual hormones and cholesterol were reduced.
Two of the patients with secondary insufficiency of sexual glands
(Noonan's syndrome) attained improvement of the libido and erections
during the treatment. The self-confidence was improved in one of them,
and in the second - hair grew in the male genital region.
The results of the treatment of three patients with cryptorchidism
(one of them with uncorrected mal- formation) comprised improvement
of the libido and often masturbation. The duration of the erection
was prolonged in one patient from that group, aged 37. The spermiogram
of the same patient was significantly better compared to the initial
status one month after treatment, i.e. on day 90 after the beginning.
One patient with secondary hypogonadism reported hair growing in the
axillary and genital region, parallel with enhanced libido and frequent
The serum testosterone levels were elevated in 20 patients from various
nozological groups, the initial and final values being within the
norm. In seven patients with testosterone serum level below the lower
limit of the norm, the physiological levels were reached after the
treatment, whereas in the rest of the patients with normal initial
levels, the testosterone was not significantly changed after treatment.
Tolerance and side effects
All clinicians engaged in the studies reported a very good tolerance
and no drug-related side effects. The clinical laboratory data on
protodioscin treated males showed no deviations in the blood count,
ESR, flocculation tests and urine.
DISCUSSION OF THE RESULTS
The clinical studies of all three research teams on a total of 212
patients (males with disorders in the sexual function) confirmed the
experimental data on a pronounced stimulating effect of the new Bulgarian
phytochemical preparation on the sexual functions. It restored and
improved the libido in all forms of impotentia coeundi after the administration
of a mean daily dose of 1.5 g for 30 - 40 days. This suggests that
not only the diminished libido was stimulated, but also that a therapeutic
effect on both primary and secondary male hypogonadism was present.
The assumption that the product has a favorable effect on spermatozoa
motility after 60-day administration corresponds to the experimental
data, according to which it stimulates both the mitosis and maturation
of the germinal cells.
It is well known that at least 80 days elapse from the time of the
division of the spermatogonia till the formation of a mature spermatozoon
in males, hence the concentrations of the spermatozoa in the semen
are different within that period. The team that used a therapeutic
course of 90 days observed very good results in terms of both the
motility and the concentration of the spermatozoa in the ejaculate.
The studies of ejaculate from patients receiving the product for 60
days proved its apparent effect on the motility of the spermatozoa
and an insignificant effect on their concentration on the basis of
identical initial spermatozoal levels, as well as the presence of
identity in the nozological groups prior to the treatment. This confirms
the fact that the minimum therapeutic cycle should last at least as
long as one complete germinal cycle (i.e. 80 - 90 days in males).
Both idiopathic oligo- and azoospermia are diseases with so far undistinguished
etiology. The serum levels of sex steroids are not changed in the
majority of the patients with such deviations and good therapeutic
levels of the product are observed. No data are available from testes
biopsy that can throw light as to which of the phases of this complicated
process of spermatogenesis has been affected pathologically and hence
favorably affected by the product. Kumanov at al. advanced the hypothesis
of diminished central effect of the product, associated with its mechanism
of action, based on the elevated level of the luteinizing hormone.
On the other hand, they admitted the existence of a peripheral effect,
which could be responsible for the effect of the product on hair growth.
The reduced level of serum cholesterol under the effect of the product
provided grounds for the same authors to assume that it also had an
effect of cholesterol metabolism. The mechanism of action of protodioscin
has not been elucidated so far. It can be concluded, on the basis
of the clinical studies carried out so far, that it has a very good
stimulating and therapeutic effect in all forms of impotentia coeundi,
as well as a very good therapeutic effect in patients with oligoasthenospermia.
The product has a very good tolerance and no undesired side effects.
Based on the data presented so far, we recommend protodioscin for
the treatment of impotentia coeundi and generaldi, due to oligospermia
and diminished motility of spermatozoa.
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