Vol. 15(2), pp. 86-95, February, 2021
DOI: 10.5897/JMPR2020.7070
Article Number: 3FA24C166151
ISSN 1996-0875
Copyright © 2021
Author(s) retain the copyright of this article
http://www.academicjournals.org/JMPR
Journal of Medicinal Plants Research
Full Length Research Paper
Aphrodisiac activity of ethanol extract and fractions of
Fadogia cienkowskii Shweinf. Rubiaceae roots in
albino rats
Jurbe Gofwan Gotep1,2*, Sunday Yakubu Sabo2, Sunday Makama3, Mary Ogonnaya Uguru2
and Francis Kanayo Okwuasaba2
1
Drug Development Division, National Veterinary Research Institute, Vom, Plateau State, Nigeria.
Pharmacology and Toxicology Department, Faculty of Pharmaceutical Sciences, University of Jos, Nigeria.
3
Biochemistry Division, National Veterinary Research Institute, Vom, Plateau State, Nigeria.
2
Received 3 December, 2020; Accepted 1 February, 2020.
Fadogia cienkowskii is a shrub whose roots are used in many communities of Northern Nigeria to
improve sexual performance; however, there is no scientific study to verify this claim. This study
determined the effect of 70% ethanol extract of F. cienkowskii roots and its fractions (ethyl acetate, nbutanol, and residual ethanol) on mating behaviour (mounting, intromission and ejaculation) and serum
testosterone concentration of male albino rats. Five groups of rats each containing 6 rats were treated
with 50, 100 and 200 mg/kg of the crude ethanol extract, while Sildenafil and distilled water were
administered to the control groups. Another set of 6 groups of rats were also used in the study and
were treated with 12.5 and 25 mg/kg of the ethyl acetate, n-butanol and residual ethanol fractions,
respectively. The crude extract and fractions significantly increased mount, intromission and
ejaculation frequencies. The copulation efficiency also increased significantly – indicative of the plant’s
aphrodisiac potential. Significant increase of testosterone in serum of extract treated rats was also
observed, which is a further credence to the plant’s aphrodisiac potential. It was thus concluded that
the 70% ethanol root extract of F. cienkowskii and its fractions have aphrodisiac activity with the nbutanol and residual ethanol fractions being more active.
Key words: Fadogia cienkowskii extract, aphrodisiac activity, rats
INTRODUCTION
Sexual function is an important index of assessing quality
of life and sexuality has wide ramifications on the social
and psychological well-being of an individual (Brody,
2006). For many people, sexual dysfunction is associated
with significant negative effects on quality of life (Avci and
Dogan, 2016; Yafi et al., 2016), sometimes requiring
medical interventions which may include lifestyle
modification (Gupta et al., 2011), surgery (Yafi et al.,
2016) and pharmacotherapy (Hatzimouratidis et al.,
2016; Yafi et al., 2016) – involving the use of aphrodisiacs
to improve sexual function and quality of life.
Medicinal plants are used to enhance sexual function in
*Corresponding author. E-mail: jurbegotep@gmail.com Tel: +2348033927539.
Author(s) agree that this article remain permanently open access under the terms of the Creative Commons Attribution
License 4.0 International License
Gotep et al.
many regions of the world. In Uganda, 30 plants from 25
families and 30 genera have been reportedly used in
managing sexual impotence and erectile dysfunction
(Kamatenesi-Mugisha
and
Oryem-Origa,
2005).
Vajikaran Rayana is a concept in Indian Ayurvedic
medicine that describes the use of medicinal plants to
improve sexual function (Chauhan et al., 2014). In
Nigeria, a substantial proportion of the population,
especially in rural areas, use plants to enhance sexual
function and treat erectile dysfunction (Afolayan and
Yakubu, 2009). Some plants that have been scientifically
shown to enhance sexual function include Schisandra
chinensis (Choi et al., 2018), Pueraria tuberosa (Maji et
al., 2014) and Fadogia agrestis (Yakubu et al., 2005).
Fadogia cienkowskii is a plant belonging to the
Rubiaceae family, an erect shrub about 3 ft high and
forms stout underground bases, distributed in the
savannah from Mali to Northern and Southern Nigeria,
and widely dispersed into the drier parts of tropical Africa
(Burkhill, 1985). The common name in Hausa is bakin
gaggai which means “black aphrodisiac”. The Igbos of
southeastern Nigeria calls it Ogwu-Agu (translated as
Lion’s drug). F. cienkowskii is used in traditional medicine
for the treatment of different ailments including general
body debility, inflammation, diarrhea, fever, malaria
(Chukwube et al., 2018), infertility (Ruffo, 1991) and male
impotence (Chukwube et al., 2018; Odeghe et al., 2016).
Despite the reported use of F. cienkowskii to enhance
male sexual performance, there is no scientific study to
verify this claim. This study evaluated the effect of F.
cienkowskii ethanolic root extract and its successive fractions
on some parameters of sexual performance in male
albino rats.
MATERIALS AND METHODS
87
Fractionation of crude extract
Fractions of the crude ethanol extract were obtained using the
method described by Hossain et al. (2014). Briefly, 50 g of the
crude extract was suspended in 200 ml of distilled water in a 500-ml
separating funnel. The suspension was successively extracted
using solvents of increasing polarity (n-hexane, ethyl acetate and nbutanol). First, 100 ml of n-hexane was added to the suspension
and gently mixed. The mixture was allowed to stand and separate
into the aqueous and hexane layers. The hexane layer was
collected and the process was repeated 3 times to obtain the
hexane fraction. In the same way, ethyl acetate and butanol were
used to extract the aqueous suspension of the ethanol extract to
obtain the n-hexane, ethyl acetate (EA), butanol (NB) and residual
ethanol (RE) fractions (Figure 1). The ethyl acetate, butanol and
residual ethanol fractions were weighed to obtain their percentage
yield.
Preliminary phytochemical screening
The crude extract and fractions were tested for the presence of
secondary metabolites using the methods described by Evans
(2009). The phytochemicals tested for were alkaloids, saponins,
tannins, cardiac glycosides, flavonoids and steroids.
Determination of acute toxicity (LD50)
The LD50 of the crude extract was determined using the method
described by Lorke (1983). Male rats weighing between 150 to 200
g were used. The determination was carried out in two phases. In
Phase I, nine rats were divided into 3 groups of 3 rats each and
labeled as Groups 1, 2 and 3. They were administered 10, 100 and
1000 mg/kg body weight dose of F. cienkowskii extract orally and
were observed for mortality or any signs of toxicity. After 24 h, the
phase II treatment was initiated with administration of 1600, 2900
and 5000 mg/kg body weight dosage of the extract each to 1 rat.
The rats were observed for mortality or signs of toxicity hourly for
the first 6 h, then after 24 h observation continued for 14 days to
assess for signs of delayed toxicity.
Plant collection authentication and preparation
F. cienkowskii roots was collected from Wuntin Dada in Bauchi
State, Nigeria in November 2016. The plant was identified by Mr
Joseph J. Azila of the Federal College of Forestry Jos and
authenticated by Prof. Emmanuel Aigbokhan. A voucher specimen
was deposited in the Federal College of Forestry herbarium with
voucher number FHJ 258. The root was cleaned of debris and dried
under shade in the Drug Development Division of National
Veterinary Research Institute, Vom, Nigeria.
The dried root was pulverized using wooden pestle and mortar
into coarse powder. Six hundred (600) grams of the pulverized
plant material was poured into a 6-L round bottom flask and 3 L of
70% ethanol was poured onto it to extract by maceration. The
mixture was allowed to stand for 72 h with shaking at intervals of 12
h. After 72 h, the mixture was successively passed through sieves
of varying pore sizes (800, 500 and 150 µm); followed by filtration
using cotton wool plug and finally Whatmann No. 1 filter paper to
obtain a clear filtrate.
The filtrate was dried by passing a steady stream of air using an
exhaust fan to reduce the volume to about one third of the original
volume. The remainder was transferred into an oven to dry at a
temperature of 40°C after which the dried extract was scrapped and
stored in air tight containers at 25 ± 2°C pending use.
Evaluation of mating performance of male rats
Preparation of male rats
Male albino rats weighing between 250 and 330 g were used for the
experiment. They were obtained from the experimental animal
house of the National Veterinary Research Institute, Vom, Nigeria.
The rats were housed in plastic cages with stainless steel cover in a
natural light/dark cycle (7 pm to 6 am dark) and were allowed free
access to food and water. The food was pelleted feed from the
Dagwom Farm Mill National Veterinary Research Institute, Vom.
Preparation of female rats
Female rats weighing between 180 and 230 g were used. They
were allowed free access to food and water. The female rats were
artificially brought to oestrus by administering oestradiol 25 µg per
rat and progesterone 500 µg 48 and 8 h respectively prior to mating
via subcutaneous injection under the skin of the neck. The
receptivity of the female rats was tested by mating with male rats
other than the ones used for the experiment (Yakubu et al., 2007;
88
J. Med. Plants Res.
Chan, 2010; Chu et al., 2014).
Experimental design
For evaluation of the crude extract, male rats were divided into five
groups each containing six rats. Group 1 rats served as the control
and were treated with distilled water at equivalent volume with the
rats taking the extract. Rats in Groups 2, 3 and 4 were treated with
50, 100 and 200 mg/kg body weight of the crude extracts while rats
in Group 5 were treated with Sildenafil 5 mg/kg. Treatment was
administered once daily for 14 days and the male rats were paired
with the females and mating behaviour observed on days 1, 7 and
14. Administration of the extract continued for 40 days after which
the rats were humanely sacrificed by ether anaesthesia and blood
collected for hormonal assay.
For evaluation of the fractions (ethyl acetate, butanol and
residual ethanol fractions), male rats weighing 250 to 330 g were
divided into 7 groups each containing 6 rats. Two doses per fraction
(12.5 and 25 mg/kg) and a control group that was administered
distilled water with volume equivalent to that of fractions
administered to constituted groups. The treatment was administered
once daily for 7 days by oral route and the mating performance was
evaluated on the 1st and 7th day.
cobas e 411.
The concentration of Follicle Stimulating Hormone (FSH) was
estimated using the FSH immunoradiometric assay (FSH IRMA)
with kits according to the manufacturer’s protocol. The assay is
based on a non-competitive principle in which the analyte is
sandwiched between two monoclonal antibodies. The first antibody
was coated on the walls of the tubes used in the analysis, while the
second antibody was radiolabeled for detection. The unbound
fraction was removed by a washing step. The amount of
radioactivity counted in the assay tubes is directly proportional to
the amount of analyte in the sample (Arslan et al., 2003; Tietz,
1995). The analysis was carried out using the automatic Roche
Diagnostics Immuno analyser cobas e 411.
The concentration of luteinizing hormone was determined by
radioimmunoassay with kits according to the manufacturer’s
protocol. The assay is based on the principle that a hormone can
be radiolabeled and still produces an immunologic and biologically
active product while possessing high specific activity (Midgley,
1966). The labeled hormone reacts with an antiserum in a
quantitative manner. Iodine 131I labeled Human Chorionic
Gonadotropin (HCG-131I) competes with un-labeled luteinizing
hormone for limited amount of antibody. The fluorescence is
proportional to the quantity of unbound hormone (Midgley, 1966;
Midgley and Jaffe, 1966; Monroe et al., 1969; Niswender et al.,
1969). The analysis was carried out using the automatic Roche
Diagnostics Immuno analyser cobas e 411.
Determination of mating performance
Male and female rats were mated in a ratio of 1:1. Each male rat
was placed in a glass cage measuring 60 cm × 30 cm × 30 cm (L ×
B × H) and allowed to acclimatize for 10 min. Thereafter, a female
that had been experimentally brought to oestrous was introduced
into the cage and allowed to cohabit for 30 min. The sequence of
events was captured using a document camera. The recorded
video was then played back to evaluate mating behaviour
parameters. The behaviours of interest were the mount,
intromission and ejaculation. A mount was defined as the male
assuming the copulation position without introducing its penis into
the female vagina. Intromission was defined as the introduction of
the male penis into the female vagina and it is characterized by
pelvic thrusting and springing dismount. Ejaculation is the ejection
of semen by the male into the female vagina. It is characterized by
deeper pelvic thrust and slow dismount followed by a period of
inactivity. The mount, intromission and ejaculation latencies and
frequencies were recorded and copulation efficiency was calculated
as
Ethical consideration
The study was conducted in accordance with guidelines for the
handling and care of experimental animals (National Research
Council, 2011). The protocol for experiments was approved by the
Animal Ethics Committee of the National Veterinary Research
Institute, Vom. Ethical Clearance Certificate No. AEC/02/34/16 was
issued.
Statistical analysis
Data were expressed as mean ± SEM (n=6). Difference between
means of various treatment groups was determined by analysis of
variance and Tukey’s post-test using SPSS version 20 IBM®,
SPSS® (NY, USA). Value of P < 0.05 was considered significant.
RESULTS
Yield of plant extract and phytochemical constituents
Determination of serum testosterone, follicle stimulating
hormone and luteinizing hormone concentration
After administration of the crude extract for 40 days, the male rats
were humanely sacrificed and blood was collected by
exsanguination into plain sample bottles. The blood was allowed to
clot and the serum to separate. The blood was then centrifuged in a
refrigerated centrifuge and the serum was aspirated into plain
sample bottles using Pasteur pipettes and stored at -20°C pending
analysis. Assay was carried out within 48 h after sample collection.
The concentration of testosterone in the serum was determined
using the testosterone enzyme immunoassay kit according to the
manufacturer’s protocol based on the principle of direct competitive
assay following antigen-antibody reaction as in the Enzyme-Linked
Immunosorbent Assay (ELISA) (Tietz, 1995). Estimation was
carried out using the automatic Roche Diagnostics Immuno analyser
The extraction yielded a dark brown and highly
hygroscopic extract with percentage yield of 5.03%. The
percentage yield of fractions from the crude extract
showed that the ethyl acetate, butanol and residual
ethanol fractions were 16.23, 22.22 and 38.06%
respectively (Table 1).
The preliminary phytochemical analysis of the crude
extract showed the presence of tannins, saponins,
steroids, terpenes, alkaloids flavonoids and cardiac
glycosides (Table 1). In the ethyl acetate fraction, tannins
and flavonoids were not detected while saponins,
steroids, terpenes, alkaloids and cardiac glycosides were
detected (Table 1). The butanol fraction tested positive
for tannins, steroids, terpenes and cardiac glycosides
while saponins, alkaloids, flavonoids were not detected.
Gotep et al.
89
Table 1. Result of phytochemical screening of crude ethanol extract and fractions of Fadogia cienkowskii roots.
Phytochemical
Tannins
Saponins
Steroids
Terpenes
Alkaloids
Flavonoids
Cardiac glycosides
Percentage yield
Crude Ethanol
+
+
+
+
+
+
+
Ethyl acetate Fraction
+
+
+
+
+
7.52
Extract
Butanol Fraction
+
+
+
+
42.68
Residual Ethanol Fraction
+
+
+
+
+
+
29.49
+ = Detected; - = Not Detected.
Table 2. Effect of Fadogia cienkowskii ethanol root extract on mount, intromission and ejaculation latencies of male albino rats after
daily treatment for 14 days.
Treatment
Distilled water 5 ml/kg
Extract 50 mg/kg
Extract 100 mg/kg
Extract 200 mg/kg
Sildenafil 5 mg/kg
Mount Latency (s)
58.33 ± 5.53
32.17 ± 7.03*
30.17 ± 4.23*
33.17 ± 5.58*
37.57 ± 3.11
Mating behavior parameter
Intromission Latency (s)
59.67 ± 4.75
33.33 ± 6.43*
31.17 ± 3.95*
34.17 ± 5.36*
34.83 ± 5.61*
Ejaculation Latency (min)
19.22 ± 5.29
10.55 ± 2.75
7.13 ± 1.76*
6.77 ± 1.68*
17.30 ± 4.23
* = P < 0.05; N = 6.
The residual ethanol fraction showed positive reactions
for tannins, saponins, steroids, terpenes, alkaloids and
cardiac glycosides while the test for flavonoids showed a
negative reaction (Table 1).
Acute toxicity
There was no mortality observed in all the rats treated
with the extracts even at the highest dose administered.
This indicated that the ethanol extract of F. cienkowskii
roots is relatively safe for the purposes of evaluation of
therapeutic activity.
Effect of crude extract on mount, intromission and
ejaculation frequency
There was no significant difference in the mount
frequency of rats treated with the extract on the first day
when compared with the control (distilled water).
However, on the 7th and 14th days of treatment, significant
increase was observed in the mount frequency of rats
treated with all doses of the extract. The same trend was
observed in the intromission frequency and copulation
efficiency. For the ejaculation frequency, a dose
dependent increase was observed which was statistically
significant (P<0.05) only at 200 mg/kg - the highest dose
administered (Table 3).
Effect of extract on mating behaviour of male rats
Effect of crude extract on copulation efficiency
Effect of crude extract on mount, intromission and
ejaculation latencies
F. cienkowskii extract significantly (P < 0.05) decreased
mount, intromission and ejaculation latencies in albino
rats over the 14 days of treatment when compared with
the control (distilled water). The mount and intromission
latencies were comparable to that of rats treated with the
standard drug sildenafil (Table 2).
The extract (200 mg/kg) significantly increased copulation
efficiency (P < 0.05) on day 1 of treatment compared to
the control whereas 50 and 100 mg/kg did not statistically
(P > 0.05) increase copulation efficiency on day 1 of
treatment. However, increased copulation efficiency was
observed after 7 and 14 days of treatment with 50, 100
and 200 mg/kg respectively which was statistically
significant (P < 0.05) compared to control. The effect of
90
J. Med. Plants Res.
Table 3. Effect of Fadogia cienkowskii ethanol root extract on mount, intromission and ejaculation frequencies of male albino
rats after daily administration for 14 days.
Treatment
Distilled water 5 ml/kg
Extract 50 mg/kg
Extract 100 mg/kg
Extract 200 mg/kg
Sildenafil 5 mg/kg
Mount
17.00 ± 1.52
23.67 ± 1.33*
24.17 ± 1.40*
25.00 ± 2.00*
27.00 ± 2.25*
Mating behavior frequency
Intromission
14.50 ± 0.99
21.67 ± 1.33*
22.17 ± 1.40*
23.00 ± 2.00*
25.00 ± 2.25*
Ejaculation
0.83 ± 0.31
2.17 ± 0.75
2.33 ± 0.67
2.83 ± 0.31*
2.68 ± 0.62*
* = P < 0.05, N = 6
D
A
B
C
Figure 1. Schematic representation of fractionation of crude ethanol root extract of Fadogia cienkowskii
A) Hexane, B) Ethylacetate, C) N-butanol, and D) Aqueous (containing residual ethanol) fractions.
the extract was both dose and time dependent.
Copulation Efficiency after 14 days of treatment is shown
in Figure 2.
RE > NB > EA (Table 5).
Effect of Fadogia cienkowskii fractions on copulation
efficiency
Effect of extract on serum testosterone, FSH and LH
concentrations
Administration of the extract (50, 100 and 200 mg/kg)
significantly (P < 0.05) increased the serum testosterone
concentration of rats when compared to control (Table 4),
while LH concentration decreased and FSH concentration
was not significantly (P < 0.05) affected (Table 4).
After treatment for 14 days, there was significant (P <
0.05) increase in the copulation efficiency of rats treated
with all the fractions of the extract when compared to that
of the control rats treated with distilled water (Figure 3).
The magnitude of increase was RE > NB > EA.
DISCUSSION
Effect of Fadogia cienkowskii fractions on mount,
intromission and ejaculation frequency
Rats treated with the extract had statistically (P < 0.05)
higher mount, intromission and ejaculation frequencies
after treatment for 7 days with the order of increase as
The 70% ethanol extract of the root of F. cienkowskii
showed positive presence for tannins, saponins, steroids,
terpenes, alkaloids flavonoids and cardiac glycosides
(Table 1). These constituents have also been reported to
be present in the leaves of the plant (Bruce et al., 2019;
Chukwube et al., 2018; Odeghe et al., 2016; Orabueze et
Gotep et al.
91
Figure 2. Copulation efficiency of rats treated with F. cienkowskii ethanol root extract daily for
14 days. * = P < 0.05. N = 6.
Table 4. Effect of Fadogia cienkowskii root extract on serum testosterone, FSH and LH concentration.
Treatment
Distilled water (5 ml/kg)
Extract (50 mg/kg)
Extract (100 mg/kg)
Extract (200 mg/kg)
Testosterone (nmol/L)
0.81 ± 0.37
9.35 ± 2.44*
6.28 ± 1.13*
4.53 ± 1.18*
Hormone
FSH (mIU/ml)
0.085 ± 0.002
0.086 ± 0.004
0.088 ± 0.006
0.085 ± 0.003
LH (mIU/ml)
0.456 ± 0.015
0.424 ± 0.030*
0.422 ± 0.020*
0.415 ± 0.005*
FSH = Follicle Stimulating Hormone, LH = Luteinizing Hormone *= P < 0.05 compared to untreated group, N = 6.
Table 5. Effect of fractions of ethanol extract of Fadogia cienkowskii root on mount, intromission and ejaculation
frequencies of male albino rats.
Treatment
DW (5 ml/kg)
EA (12.5 mg/kg)
EA (25 mg/kg)
NB (12.5 mg/kg)
NB (25 mg/kg)
RE (12.5 mg/kg)
RE (25 mg/kg)
Mount
20.00 ± 6.93
20.67 ± 0.92
26.67 ± 4.62*
25.33 ± 1.97*
30.33 ± 0.46*
33.67 ± 4.67*
28.0 ± 3.17*
Mating behavior frequency
Intromission
13.50 ± 0.67
16.33 ± 1.73
22.67 ± 3.75*
24.00 ± 0.97*
29.00 ± 0.37*
32.33 ± 4.10*
27.00 ± 2.90*
Ejaculation
0.50 ± 0.37
1.33 ± 0.61*
2.33 ± 0.23*
3.00 ± 0.40*
2.33 ± 0.23*
3.33 ± 0.23*
3.33 ± 0.23*
* = P < 0.05 compared to untreated group in the same column, N = 6, DW = Distilled Water, EA = Ethyl acetate fraction, NB = NButanol fraction, RE = Residual ethanol fraction.
al., 2019). However, to the best of our knowledge, this is
the first report on the constituents of the roots. Saponins
and alkaloids have been associated with enhancing
aphrodisiac activity. Protodioscin is a saponin found in
Tribulus terrestris and has been shown to increase mount
and intromission frequencies; decrease mount latency,
92
J. Med. Plants Res.
Figure 3. Copulation efficiency of rats treated with Fadogia cienkowskii fractions daily for 14 days. DW
= Distilled Water, EA = Ethyl acetate fraction, NB = N-Butanol fraction, RE = Residual ethanol fraction.
* = P < 0.05, ** = P < 0.01. N = 6.
intromission latency and post ejaculation interval as well
as increase intracavernosal pressure in rats (Gauthaman
and Ganesan, 2008). The alkaloid fraction of the seeds of
Hygrophila spinosa reportedly increased testosterone
production by Leydig cells in vitro and increased mount
and intromission frequency in male rats (Vyas and Raval,
2016). Arecoline, which is an alkaloid derived from the
betel nuts (Areca catechu) has also been shown to
increase testosterone secretion by the Leydig cells in rats
(Wang et al., 2008).
It is interesting that flavonoids detected in the crude
extract was not detected in any of the fractions evaluated
(ethyl acetate, butanol and residual ethanol). This
observation raises questions that need further
investigation. A possible reason may be our inability to
carry out phytochemical screening of the n-hexane
fraction. The aphrodisiac activity of the n-hexane fraction
was also not evaluated due to low yield.
The absence of mortality in the acute toxicity test at
5000 mg/kg dose suggests the safety of the ethanol root
extract of F. cienkowskii. No apparent toxic effect had
been associated with the folkloric use of F. cienkowskii.
This finding agrees with reports that the LD50 of the
methanol and hydromethanol extract of the leaves of F.
cienkowskii is higher than 4000 mg/kg (Ode et al., 2015;
Orabueze et al., 2019).
In the evaluation of aphrodisiac activity, the significantly
shorter mount latency of rats treated with the extract
compared with that of control rats treated with distilled
water is indicative of sexual behaviour
stimulating
activity of the extract; particularly the desire or appetite
component of sexual behaviour. While there are no
studies evaluating the aphrodisiac potential of the root
extract of F. cienkowskii, it is interesting that F. agrestis
has been reported to significantly decrease mount
latency in albino rats (Yakubu et al., 2005).
Significantly lower intromission latency in rats is
indicative of the ability of the extract to also increase the
arousal and potency components of mating. Successful
intromission indicates potency and functional penile
erectile mechanisms which occurs only when the male
copulation organ is sufficiently erect to penetrate the
female organ. Substances with aphrodisiac potential have
been reported to significantly reduce the intromission
latency (Yakubu et al., 2007).
The shortened ejaculation latency observed is an
indication of the ability of the extract to stimulate sexual
activity in rats. It is known that drugs which inhibit sexual
function such as Selective Serotonin Reuptake Inhibitors
(Chan, 2010), some antihypertensives (Seidl et al., 1991)
and antipsychotics (Allen et al., 2019) prolong ejaculation
latency. Drugs that stimulate sexual activity on the other
hand decrease ejaculation latency and increase
ejaculation frequency (Chan, 2010). These findings agree
with those of Gundidza et al. (2009) and Allouh et al.
(2014) where administration of Mondia whitei and Allium
cepa extract respectively to rabbits and rats decreased
mount, intromission and ejaculation latencies. In addition,
administration of A. cepa attenuated paroxetine-induced
prolongation of ejaculation latency. In this study,
Gotep et al.
significant decrease in mount and intromission latencies
along with decrease in ejaculation latency observed in
rats does not agree with the findings of Yakubu et al.
(2005) and Suresh et al. (2009). These authors reported
significant increase in ejaculation latency of rats but their
treatment was with F. agrestis aqueous stem extract and
Mucuna pruriens ethanol seed extract respectively.
Mount frequency is considered as an index of sexual
motivation and stamina (Gauthaman et al., 2002; Yakubu
et al., 2007). The significant increase in mount frequency
of rats treated with the crude root extract shows that F.
cienkowskii extract increased sexual motivation and
stamina of the rats.
The increased intromission frequency of rats treated
with the extract may be an indication of increased erectile
function. The decrease in intromission latency coupled
with increased intromission frequency further supports
the probable erectile function enhancing activity of F.
cienkowskii. Furthermore, sexual stimulation usually
manifests in higher frequency of ejaculation within a
specified time period (Chan, 2010). In our study, a cut-off
period of thirty minutes was used. The significantly higher
frequency of ejaculation in rats treated with the extracts
on day 7 and 14 of treatment suggests that the extract
possesses sexual stimulation activity and extended
administration could lead to a furtherance of enhanced
sexual activity.
Copulation efficiency is a measure of sexual potency
and index of successful intromission at every attempt.
The higher copulation efficiency of rats treated with the
extracts is a further indication that the extract enhanced
sexual potency.
When all the results are considered together, the
overall improvement in the parameters of sexual
stimulation and stamina indicate that the aqueous ethanol
root extract of F. cienkowskii has aphrodisiac potential.
Similarly, the fractions of the crude extract also showed
significant increases in copulation efficiency signifying
further their ability to increase mating potency of rats
even at lower doses than those used to evaluate
aphrodisiac activity of the crude ethanol extract.
Significant increase in serum testosterone concentration
of rats treated with the crude extract suggests that the
extract enhances steroidogenesis. It is plausible that the
significant increase in testosterone in rats treated with the
extract may in part account for their sexual behaviour
enhancing activity. Testosterone supplementation has
been reported to improve sexual function and libido (Rizk
et al., 2017). Androgen deficiency in castrated rats has
been shown to impair penile erectile function (Alcorn et
al., 1999). Conversely, testosterone replacement has
been shown to maintain smooth muscle content in the
corpus cavernosum of castrated rats (Halmenschlager et
al., 2017) and increased the intensity of orgasms and
ejaculation in men (Morales, 1996). The significant
increase in testosterone concentration was accompanied
by a significant decrease in luteinizing hormone (LH)
concentration. Increased level of testosterone is usually
93
accompanied by lower concentration of luteinizing
hormone (Bridges et al., 1993; Plant and Dubey, 1984),
due to the inhibitory effect of testosterone on the
hypothalamus through negative feedback, thus limiting
the release of gonadotropin releasing hormone by the
hypothalamus (Shibata et al., 2007; Finkelstein et al.,
1991; Steiner et al., 1982).
Conclusion
The aphrodisiac potential of F. cienkowskii ethanol roots
extract and its fractions were evaluated in male albino
rats. Results obtained showed enhanced mating
behaviour parameters of mount, intromission, ejaculation
and copulation efficiency. In addition, the ethanol extract
increased serum concentration of testosterone and this
may in part be a possible mechanism of action of the
extract. Further work on the mechanism of action of the
extract and determination of the active compounds is
recommended.
CONFLICT OF INTERESTS
The authors have not declared any conflict of interests.
REFERENCES
Afolayan AJ, Yakubu, MT (2009). Erectile dysfunction management
options in Nigeria. Journal of Sexual Medicine 6(4):1090-1102.
https://doi.org/10.1111/j.1743-6109.2008.01064.x
Alcorn JF, Toepfer JR, Leipheimer RE (1999). The effects of castration
on relaxation of rat corpus cavernosum smooth muscle in vitro. The
Journal
of
Urology
161(2):686-689.
http://www.ncbi.nlm.nih.gov/pubmed/9915483
Allen K, Baban A, Munjiza J, Pappa S (2019). Management of
Antipsychotic-Related Sexual Dysfunction: Systematic Review.
Journal
of
Sexual
Medicine
16(12):1978-1987.
https://doi.org/10.1016/j.jsxm.2019.08.022
Allouh MZ, Daradka HM, Barbarawi MMA, Mustafa AG (2014). Fresh
onion juice enhanced copulatory behavior in male rats with and
without paroxetine-induced sexual dysfunction. Experimental Biology
and
Medicine
239(2):177-182.
https://doi.org/10.1177/1535370213508360
Arslan AA, Zeleniuch-Jacquotte A, Lukanova A, Rinaldi S, Kaaks R,
Toniolo P (2003). Reliability of follicle-stimulating hormone
measurements in serum. Reproductive Biology and Endocrinology
1:1-5. https://doi.org/10.1186/1477-7827-1-49
Avci D, Dogan S (2016). The impact of sexual dysfunction and quality of
life of patients with asthma in Turkey. Sexuality and Disability
35(1):107-118. https//doi.org/10.1007/S11195-016-9468-2.
Bridges NA, Hindmarsh PC, Pringle PJ, Matthews DR, Brook CGD
(1993). The relationship between endogenous testosterone and
gonadotrophin secretion. Clinical Endocrinology 38(4):373-378.
https://doi.org/10.1111/j.1365-2265.1993.tb00517.x
Brody S (2006). Blood pressure reactivity to stress is better for people
who recently had penile-vaginal intercourse than for people who had
other or no sexual activity. Biological Psychology 71(2):214-222.
https://doi.org/10.1016/j.biopsycho.2005.03.005
Bruce S, Onyegbule F, Ezugwu CO (2019). Pharmacognostic ,
physicochemical and phytochemical evaluation of the leaves of
Fadogia
cienkowskii
Schweinf
(Rubiaceae).
Journal
of
Pharmacognosy
and
Phytotherapy
11(3):52-60.
https://doi.org/10.5897/JPP2019.0552
94
J. Med. Plants Res.
Burkhill HM (1985). Useful Plants of West tropical Africa (2nd ed.).
Royal Botanical Gardens, Kews.
Chan J (2010). In search of animal models for male sexual dysfunction.
PhD. Dissertation, Division of Pharmacology, Utrecht Institute for
Pharmaceutical
Sciences.
http://igiturarchive.library.uu.nl/dissertations/2010-1105-200234/UUindex.html
Chauhan NS, Sharma V, Dixit VK, Thakur M (2014). A review on plants
used for improvement of sexual performance and virility. BioMed
Research
International,
Article
ID
868062
1-19.
https://doi.org/10.1155/2014/868062
Choi BR, Kim HK, Park JK (2018). Effects of Schisandra chinensis fruit
extract and gomisin A on the contractility of penile corpus
cavernosum smooth muscle: A potential mechanism through the
nitric oxide - cyclic guanosine monophosphate pathway. Nutrition
Research
and
Practice
12(4):291-297.
https://doi.org/10.4162/nrp.2018.12.4.291
Chu X, Zhavbert ES, Dugina JL, Kheyfets IA, Sergeeva, SA, Epstein OI,
Ågmo A (2014). Effects of chronic treatment with the eNOS stimulator
Impaza on penis length and sexual behaviors in rats with a high
baseline of sexual activity. International Journal of Impotence
Research 26(1):35-40. https://doi.org/10.1038/ijir.2013.12
Chukwube VO, Ezugwu CO, Odoh UE, Inya-Agha SI, Ugwuja CO.
(2018). Pharmacognostic standardization of the leaf of Fadogia
cienkowskii Shweinf. fam . Rubiaceae. Journal of Pharmacognosy
and Phytochemistry 7(6):1971-1975.
Evans WC (2009). Trease and Evans Pharmacognosy (16th Edition).
Saunders, Elsevier.
Finkelstein JS, Whitcomb RW, O'Dea LS, Longcope C, Schoenfeld DA,
Crowley WF Jr. (1991). Sex steroid control of gonadotropin secretion
in the human male. I. Effects of testosterone administration in normal
and gonadotropin-releasing hormone-deficient men. Journal of
Clinical Endocrinology and Metabolism 73(3):609-20. doi:
10.1210/jcem-73-3-609.
Gauthaman K, Adaikan PG, Prasad RNV (2002). Aphrodisiac properties
of Tribulus Terrestris extract (Protodioscin) in normal and castrated
rats. Life Sciences 71(12):1385-1396. https://doi.org/10.1016/S00243205(02)01858-1
Gauthaman K, Ganesan AP (2008). The hormonal effects of Tribulus
terrestris and its role in the management of male erectile dysfunction
- an evaluation using primates, rabbit and rat. Phytomedicine 15(12):44-54. https://doi.org/10.1016/j.phymed.2007.11.011
Gundidza GM, Mmbengwa VM, Magwa ML, Ramalivhana NJ,
Mukwevho NT, Ndaradzi W, Samie A (2009). Aphrodisiac properties
of some Zimbabwean medicinal plants formulations. African Journal
of Biotechnology 8(22):6402-6407.
Gupta BP, Murad MH, Clifton MM, Prokop L, Nehra A, Kopecky SL
(2011). The effect of lifestyle modification and cardiovascular risk
factor reduction on erectile dysfunction: A systematic review and
meta-analysis. Archives of Internal Medicine 171(20):1797-1803.
https://doi.org/10.1001/archinternmed.2011.440
Halmenschlager G, Rhoden EL, Motta GA, Sagrillo FL, Medeiros JL,
Meurer R, Rhoden CR (2017). Testosterone replacement maintains
smooth muscle content in the corpus cavernosum of orchiectomized
rats.
Asian
Journal
of
Urology
4(4):223-229.
https://doi.org/10.1016/j.ajur.2017.02.001
Hatzimouratidis K, Salonia A, Adaikan G, Buvat J, Carrier S, El-Meliegy
A, McCullough A, Torres LO, Khera M (2016). Pharmacotherapy for
Erectile Dysfunction: Recommendations from the Fourth International
Consultation for Sexual Medicine (ICSM 2015). Journal of Sexual
Medicine 13(4):465-488. https://doi.org/10.1016/j.jsxm.2016.01.016
Hossain MA, Al-Hdhrami SS, Weli AM, Al-Riyami Q, Al-Sabahi JN
(2014). Isolation, fractionation and identification of chemical
constituents from the leaves crude extracts of Mentha piperita L
grown in Sultanate of Oman. Asian Pacific Journal of Tropical
Biomedicine
4(Suppl
1):S368-S372.
https://doi.org/10.12980/APJTB.4.2014C1051
Kamatenesi-Mugisha M, Oryem-Origa H (2005). Traditional herbal
remedies used in the management of sexual impotence and erectile
dysfunction in western Uganda. African Health Sciences 5(1):40-49.
https://doi.org/10.4314/ahs.v5i1.6896
Lorke D. (1983). A new approach to practical acute toxicity testing.
Archives of Toxicology 54(4):275-287.
https://doi.org/10.1007/BF01234480.
Maji AK, Pandit S, Banerji P, Banerjee D (2014). Pueraria tuberosa: a
review on its phytochemical and therapeutic potential. Natural
Product
Research
28(23):2111-2127.
https://doi.org/10.1080/14786419.2014.928291
Midgley AR (1966). Radioimmunoassay: a method for human chorionic
gonadotropin and human luteinizing hormone. Endocrinology
79(1):10-18. https://doi.org/10.1210/endo-79-1-10
Midgley AR, Jaffe RB (1966). Human luteinizing hormone in serum
during the menstrual cycle: determination by radioimmunoassay. The
Journal of Clinical Endocrinology and Metabolism 26(12):1375-1381.
https://doi.org/10.1210/jcem-26-12-1375
Monroe SE, Rebar RW, Gay VL, Midgley AR (1969).
Radioimmunoassay determination of luteinizing hormone during the
estrous cycle of the rat. Endocrinology 85(4):720-724.
https://doi.org/10.1210/endo-85-4-720
Morales A (1996). Androgen supplementation in practice: the treatment
of erectile dysfunction associated with hypotestosteronemia. In:
Oddens BJ, Vermeulen A (Eds.), Androgens and aging male (pp.
233-245). Parthenon Publishing Group.
National Research Council (2011). Guide for the care and use of
Laboratory animals (8th edition). The National Academies Press.
Nicolosi A, Moreira ED, Villa M, Glasser DB (2004). A population study
of the association between sexual function, sexual satisfaction and
depressive symptoms in men. Journal of Affective Disorders
82(2):235-243. https://doi.org/10.1016/j.jad.2003.12.008
Niswender GD, Reichert LE, Midgley AR, Nalbandov AV (1969).
Radioimmunoassay for bovine and ovine luteinizing hormone.
Endocrinology 84(5):1166-1173. https://doi.org/10.1210/endo-84-51166
Ode OJ, Omeje JN, Nuhu U, Oladele GM, Madubuike SA (2015). The
Central and Peripheral effects of the methanol extract of Fadogia
cienkowskii schweinf. var cienkowskii Leaves. IOSR Journal of
Pharmacy and Biological Sciences (IOSR-JPBS) 10(6):6-11.
https://doi.org/10.9790/3008-10610611
Odeghe OB, Monanu MO, Anacletus FC (2016). Phytochemistry of
Achomanes difformis Stem, Dioscorea bulbifera Stem Bark, Fadogia
cienkowskii Leaf, Hannoa klaineana Stem and Vitex simplicifolia
Leaf. Advances in Multidisciplinary and Scientific Research 2(1):1-8.
Orabueze CI, Adesegun SA, Ejeatuluchukwu O, Ota DA, Coker HA
(2019). In vivo antimalarial and in vitro antioxidant activities of hydromethanol leaf extract of Fadogia cienkowskii Schweinf. (Rubiaceae).
African Journal of Pharmacy and Therapeutics 8(1):6-13.
Plant TM, Dubey AK (1984). Evidence from the rhesus monkey
(Macaco, mulatto) for the view that negative feedback control of
luteinizing hormone secretion by the testis is mediated by a
deceleration of hypothalamic gonadotropin-releasing hormone pulse
frequency.
Endocrinology
115(6):2145-2153.
https://doi.org/10.1210/endo-115-6-2145
Rizk PJ, Kohn TP, Pastuszak AW, Khera M. (2017). Testosterone
therapy improves erectile function and libido in hypogonadal men.
Current
Opinion
in
Urology
27(6):511-515.
https://doi.org/10.1097/MOU.0000000000000442
Ruffo CK (1991). A Survey of medicinal plants in Tabora region,
Tanzania. Proceeding of International Conference on Traditional
Medicinal Plants, Dar Es Salaam University Press, Ministry of Health,
Tanzania 131-146.
Seidl A, Bullough B, Haughey B, Scherer Y, Rhodes M, Brown G
(1991). Understanding the Effects of a Myocardial Infarction on
Sexual Functioning: A Basis for Sexual Counseling. Rehabilitation
Nursing
16(5):255-264.
https://doi.org/10.1002/j.20487940.1991.tb01230.x
Shibata M, Friedman RL, Ramaswamy S, Plant TM (2007). Evidence
that down regulation of hypothalamic KiSS-1 expression is involved in
the negative feedback action of testosterone to regulate luteinising
hormone secretion in the adult male rhesus monkey (Macaca
mulatta). Journal of Neuroendocrinology 19(6):432-438. doi:
10.1111/j.1365-2826.2007.01549.x.
Steiner RA, Bremner WJ, Clifton DK (1982). Regulation of Luteinizing
Hormone Pulse Frequency and Amplitude by Testosterone in the
Adult
Male
Rat.
Endocrinology
111(6):2055-2061.
https://doi.org/10.1210/endo-111-6-2055
Gotep et al.
Suresh S, Prithiviraj E, Prakash S (2009). Dose- and time-dependent
effects of ethanolic extract of Mucuna pruriens Linn. seed on sexual
behaviour of normal male rats. Journal of Ethnopharmacology
122(3):497-501. https://doi.org/10.1016/j.jep.2009.01.032
Tietz NW (1995). Clinical Guide to Laboratory tests (3rd ed.). WB.
Saunders.
Vyas NY, Raval MA (2016). Aphrodisiac and spermatogenic potential of
alkaloidal fraction of Hygrophila spinosa T. Ander in rats. Journal of
Ethnopharmacology
194:947-953.
https://doi.org/10.1016/j.jep.2016.10.080
Wang SW, Hwang GS, Chen TJ, Wang PS (2008). Effects of arecoline
on testosterone release in rats. American Journal of Physiology Endocrinology
and
Metabolism
295(2):E497-E504.
https://doi.org/10.1152/ajpendo.00045.2008
Yafi FA, Jenkins L, Albersen M, Corona G, Isidori AM, Goldfarb S,
Maggi M, Nelson CJ, Parish S, Salonia A, Tan R, Mulhall JP,
Hellstrom WJ (2016). Erectile Dysfunction. Nature Reviews Disease
Primer 2:1-20. https://doi.org/10.1038/nrdp.2016.3
95
Yakubu MT, Akanji MA, Oladiji AT (2007). Male Sexual Dysfunction and
Methods used in Assessing Medicinal Plants with Aphrodisiac
Potentials.
Pharmacognosy
Reviews
1(1):49-56.
https://doi.org/citeulike-article-id:7290532
Yakubu MT, Akanji, MA, Oladiji AT (2005). Aphrodisiac potentials of the
aqueous extract of Fadogia agrestis (Schweinf. Ex Hiern) stem in
male albino rats. Asian Journal of Andrology, 7(4):399-404.
https://doi.org/10.1111/j.1745-7262.2005.00052.x