The effects of Ginger on spermatogenesis and sperm parameters of rat

Abstract

Background: Ginger rhizome (Zingiber officinale R., family: Zingiberaceae) is used medicinally and as a culinary spice. Objective: Medicinal use of ginger dates back to ancient China and India. Ginger and its constituents are stated to have antiemetic, antithrombotic, antihepatotoxic, anti-inflammatory, stimulant, cholagogue and antioxidant. It has been used since ancient time as medicinal and food origins it contain antioxidative and androgenic activities and have well effect in diseases treatment in more countries world-wide. As an antioxidant's ginger has a useful effect on spermatogenesis and sperm parameters. Materials and Methods: Wistar male rat (n=30) were allocated into three groups, control (n=10) and test groups (n=20), that subdivided into groups of 2 that received ginger rhizome powder (50 and 100mg/kg/day) for 20 consequence day. Animals were kept in standard conditions. In twentieth day the testes tissue of Rats in whole groups were removed and sperm was collected from epididymis and prepared for analysis. Results: Serum total testosterones significantly increased in experimental group that has received 100 mg/kg/day Ginger (p<0.05) in comparison to control group. Besides, the percentage of sperm viability and motility in both test groups significantly increased (p<0.05) in comparison to control group, Whereas, LH, FSH hormones, sperm concentration, morphology and testes weights in both experimental and control group were similar. Conclusion: Results revealed that administration of 100 mg/kg/day of ginger significantly increased sperm percentage, viability, motility and serum total testosterones. This suggested that ginger may be promising in enhancing sperm healthy parameters.

Full text

Iranian Journal of Reproductive Medicine Vol.7. No.1. pp: 7-12, Winter 2009
The effects of Ginger on spermatogenesis and sperm
parameters of rat
Arash Khaki1 D.V.M., Ph.D., Fatemeh Fathiazad2 Ph.D., Mohammad Nouri3 Ph.D., Amir Afshin
Khaki4 Ph.D., Chelar C Ozanci5 D.D.S., Ph.D., Marefat Ghafari-Novin6 M.D., Ph.D., Mohammad
Hamadeh7 D.V.M., Ph.D.
1 Department of Veterinary Pathology (YRC), Islamic Azad University Tabriz Branch, Tabriz, Iran.
2 Department of Pharmacognosy, Tabriz University of Medical Sciences, Tabriz, Iran.
3 Department of Biochemistry Science, Tabriz University of Medical Sciences, Tabriz, Iran.
4 Department of Anatomical Science, National Public Health Management Center (NPMC), Tabriz
University of Medical Sciences, Tabriz, Iran.
5 Department of Embryology and Histology, Acdeniz University, Antalya, Antalya, Turkey.
6 Department of Cell and Molecular Biology Research Center, Shaheed Beheshti University M.C.,
Tehran, Iran.
7 Department of Obstetrics and Gynecology, University of Saarland, Germany.
Received: 11 August 2008; accepted: 6 February 2009
Abstract
Background: Ginger rhizome (Zingiber officinale R., family: Zingiberaceae) is used
medicinally and as a culinary spice.
Objective: Medicinal use of ginger dates back to ancient China and India. Ginger and
its constituents are stated to have antiemetic, antithrombotic, antihepatotoxic, anti-
inflammatory, stimulant, cholagogue and antioxidant. It has been used since ancient
time as medicinal and food origins it contain antioxidative and androgenic activities and
have well effect in diseases treatment in more countries world-wide. As an antioxidant’s
ginger has a useful effect on spermatogenesis and sperm parameters.
Materials and Methods: Wistar male rat (n=30) were allocated into three groups,
control (n=10) and test groups (n=20), that subdivided into groups of 2 that received
ginger rhizome powder (50 and 100mg/kg/day) for 20 consequence day. Animals were
kept in standard conditions. In twentieth day the testes tissue of Rats in whole groups
were removed and sperm was collected from epididymis and prepared for analysis.
Results: Serum total testosterones significantly increased in experimental group that has
received 100 mg/kg/day Ginger (p<0.05) in comparison to control group. Besides, the
percentage of sperm viability and motility in both test groups significantly increased
(p<0.05) in comparison to control group, Whereas, LH, FSH hormones, sperm
concentration, morphology and testes weights in both experimental and control group
were similar.
Conclusion: Results revealed that administration of 100 mg/kg/day of ginger
significantly increased sperm percentage, viability, motility and serum total
testosterones. This suggested that ginger may be promising in enhancing sperm healthy
parameters.
Key words: Ginger rhizome, Sperm, Spermatogenesis, Rat, Testis, Testosterone.
Introduction
Infertility is one of the major health problems in
life, and approximately 30 % of infertilities are
Corresponding Author:
Arash Khaki, Department of Veterinary Pathology,
Islamic Azad University Tabriz Branch, Tabriz, Iran.
E-mail: arashkhaki@yahoo.com
due to a male factor (1, 2). Several conditions can
interfere with spermatogenesis and reduce sperm
quality and production. More factors such as drug
treatment, chemotherapy, toxins, air pollutions and
insufficient vitamins intake have harmful effects
on spermatogenesis and sperm normal production
(3). Several studies have reported that antioxidants
and vitamin A, B, C, and E in diet can protect

Khaki et al
Iranian Journal of Reproductive Medicine Vol.7. No.1. pp: 7-12, Winter 2009
8
sperm DNA from free radicals and increase blood
testis barrier stability (4, 5). Nowadays ginger
rhizome (Zingiber officinale R., family:
Zingiberaceae), is used worldwide as a spice. Both
antioxidative (6) and androgenic activity (27) of Z.
officinale were reported in animal models. All
major active ingredients of Z. officinale, such as
Zingerone, Gingerdiol, Zingibrene, gingerols and
shogaols, have antioxidant activity (7). Besides,
other researches showed that ginger oil has
dominative protective effect on DNA damage
induced by H2O2 and might act as a scavenger of
oxygen radical and might be used as an antioxidant
(8).
Antioxidants protect DNA and other important
molecules from oxidation and damage, and can
improve sperm quality and consequently increase
fertility rate in men (9, 10).
Therefore, the role of nutritional and
biochemical factors in reproduction and sub-
fertility treatment is very important. The present
study was planned to asses the ability of ginger to
promote sperm parameters and modulate follicle
stimulating hormone (FSH), luteinizing hormone
(LH), testosterone concentration, spermatogenesis
and oxidative stress. The results obtained will
provide further insights into appropriate treatment
of male patients by improving spermatogenesis and
sperm parameters.
Materials and methods
Experimental animals
Adult Wistar albino male rats (n=30) were
included in the present study. The rats were 8
weeks old and weighing 250±10g each. They were
obtained from animal facility of Pasture Institute of
Iran. Male rats were housed in temperature
controlled rooms (25C) with constant humidity
(40-70%) and 12h/12h light/ dark cycle prior to
experimental protocols. All animals were treated in
accordance to the Principles of Laboratory Animal
Care. All rats were fed a standard diet and water.
The daily intake of animal water was monitored at
least one week prior to start of treatments in order
to determine the amount of water needed per
experimental animal. Thereafter, the rats were
randomly divided into control (n=10) and
experimental (n=20) groups. The control group just
received 4CC distilled water daily. However, the
experimental groups split into two groups each
included ten rates. (G.1) received 50mg/kg/rat and
(G.2) received 100mg/kg/rat of ginger for 20
consequence days. Body weight daily intake of
food and water were determined several times per
week throughout the study (11).
Surgical procedure
In twentieth day, the Pentobarbital sodium (40
mg/kg) was administered intra peritoneal for
anesthesia, and the peritoneal cavity was opened
through a lower transverse abdominal incision.
Thereafter testis in control and experimental
groups were immediately removed. The weights of
testis in each group were registered. The animals
were decapitated between 9:00 AM and 11:00 AM,
and blood samples were obtained. Blood samples
were centrifuged at 4°C for 10 min at 250Xg and
the serum obtained was stored at −20°C until
assayed.
Epididymis sperm count, viability and motility
Sperms from the cauda epididymis were
released by cutting into 2 ml of medium (Hams
F10) containing 0.5% bovine serum albumin
(11).After 5 min incubation at 37C (with 5%
CO2), the cauda epididymis sperm reserves were
determined using the standard hemocytometric
method and sperm motility was analyzed with
microscope (Olympus IX70) at 10 field and
reported as mean of motile sperm according to
WHO method (12).
Serum FSH, LH total testosterone hormone
measurements
Serum concentration of FSH and LH were
determined in duplicated samples using
radioimmunoassay (RIA). Rat FSH / LH kits
obtained from Biocode Company-Belgium,
according to the protocol provided with each kit.
The sensitivities of hormone detected per assay
tube were 0.2ng/ml and 0.14ng/ml for FSH and LH
respectively. Serum concentration of total
testosterone was measured by using a double
antibody RIA kit from immunotech Beckman
Coulter Company-USA. The sensitivities of
hormone detected per assay tube were 0.025ng/ml
(13, 14)
Total antioxidant capacity (TAC) and
Malondialdehyde (MDA) concentration
measurement in serum
A TAC detecting kit was obtained from Nanjing
Jiancheng Bioengineering Institute-China.
According to this method, the antioxidant defense
system, which consists of enzymatic and non-
enzymatic antioxidants, is able to reduce Fe3+ to
Fe2+. TAC was measured by the reaction of
phenanthroline and Fe2+ using a
spectrophotometer at 520 nm. At 37°C, a TAC unit
is defined as the amount of antioxidants required to
make absorbance increase 0.01 in 1 mL of serum
(15). Free radical damage was determined by

The effects of Ginger rhizome on sperms of rat
Iranian Journal of Reproductive Medicine Vol.7. No.1. pp: 7-12, Winter 2009
9
specifically measuring malondialdehyde (MDA).
MDA was formed as an end product of lipid
peroxidation which was treated with thiobarbituric
acid to generate a colored product that was
measured at 532 nm (MDA detecting kit from
Nanjing Jiancheng Bioengineering Institute-China)
(16).
Histopathology and Light microscopy
The testis was fixed in 10% formalin and
embedded in paraffin. Five-micron thick sections
were prepared and stained with Hematoxylin and
Eosin (H&E). The specimens were examined
under Olympus/3H light microscope-Japan.
Statistical analysis
Statistical comparisons were made using the
ANOVA test for comparison of data in the control
group and the experimental groups. The results
were expressed as mean ± S.E.M (standard error of
means). Significant difference is written in
parentheses.
Results
Weight of individual male testis
The obtained results in this study are illustrated
in tables I. There was no significant difference in
testes weights between the groups.
Results of sperm motility, viability and count
Administration of 50mg/kg/rat and
100mg/kg/rat ginger for twenty consecutive days
significantly increased Sperm motility and viability
in both experimental groups as compared with the
control group. The motility and vitality were
(73±4.35% and 95.80±1.68%) in G.1 and the
corresponding value in G.2 were (81±5.33%;
98.80±80%). However, the motility and vitality in
control group were significantly lower in
comparison to the values in G.1 and G.2
(33.75±6.88%; and 66.25±4.73%) (Table I). In
addition, sperm concentrations were similar in
control and both experimental groups. The results
were as follow: Control group, 48.68±7.70mill/ml;
G.1= 51.90±5.36mill /ml and 61.60±2.34 mill/ml
in G.2) (Table I).
Results of serum total testosterone, LH and
FSH hormones measurement
Administration of 50mg/kg/rat and
100mg/kg/rat ginger for twenty consecutive days
hadn’t significant effect on LH and FSH
concentration in the serum between the control and
G.1 and G.2 groups. The concentration of LH and
FSH were (1.66±0.316 and 21.59±2.69) in G.1 and
the corresponding value in G.2 were (2.23±0.453
and 21.68±2.11) However, the LH and FSH in
control group were (1.51±0.138and 20.37±1.788)
(Table I). In addition, serum total testosterone level
increased significantly (p<0.05) in animals
received 100mg/kg/rat ginger (G.2) in comparison
to control group. The concentration of serum total
testosterone level was (2.91±0.349, 3.71±0.387and
1.60±0.091 ngr/ml, respectively) in G.1, G.2 and in
control group (Table I).
Results of total antioxidant capacity (TAC) and
Malondialdehyde (MDA) concentration
measurement in Serum
The mean concentration of Malondialdehyde
(MDA) level was significantly (p<0.05) lower in
G.1 (2.64±0.193) and G.2 (0.81±0.192) in
comparison to control group (4.80±0.212).Total
antioxidant capacity (TAC) was significantly
higher (p<0.05) in G.1 (0.92±0.016) and G.2
(0.88±0.341) as compared with control group
(0.53±0.77) (Table I).
Table I. The effect of the 50mg/kg/rat and 100mg/kg/rat ginger on sperm parameters, serum FSH, LH, total Testosterone and testis
weight of control and experimental groups in the rats.
Control(n=10)
G. 1 Ginger rhizome
(50mg/kg-perday) (n=10)
G.2 Ginger rhizome
(100mg/kg-perday) (n=10)
Testis (gr)
1.40±0.821
1.47±0.373
1.41±0.479
Sperm concentration (total count) (No of sperm/rat 106)
48.68±7.70
51.90±5.36
61.60±2.34*
Motility (℅)
33.75±6.88
73±4. 35*
81±5.33*
Viability(℅)
66.25±4.73
95.80±1.68*
98.80±80*
Serum Testosterone levels (ngr/ml)
1.60±0.091
2.91±0.349
3.71±0.387*
LH levels (ngr/ml)
1.51±0.138
1.66±0.316
2.23±0.453
FSH levels (ngr/ml)
20.37±1.788
21.59±2.69
21.68±2.11
Total Antioxidant capacity (TAC)
0.53±0.777
0.92±0.016*
0.88±0.341*
Malondialdehyde (MDA)
4.80±0.212
2.64±0.193*
0.81±0.192*
Data are presented as mean ± SE.
*Significant different at p< 0.05 level, (compared with the control group).

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Iranian Journal of Reproductive Medicine Vol.7. No.1. pp: 7-12, Winter 2009
10
Result of light microscopic study
Histopathological study showed the cycle of
spermatogenesis was regular in all experimental
and control group. However, in all animals
exposed to 50mg/kg/rat and 100mg/kg/rat ginger
accumulations of sperm, in lumen of seminiferous
tubules were seen (Figure 1).
Figure 1. A) Regular seminiferous tubule with normal
germinal epithelium morphology, (x640). B) Regular
seminiferous tubule with normal germinal epithelium
morphology in 50mg/kg/rat of ginger (G.1) group. (x640). C)
Regular seminiferous tubule with normal germinal epithelium
morphology and sperm presence In lumen (arrow) in
100mg/kg/rat of ginger (G.2) group. (x640).
Discussion
The main pharmacological actions of ginger
and compounds isolated there from include
immuno-modulatory, anti-tumorigenic, anti-
inflammatory, anti-apoptotic, anti-hyperglycemic,
anti-lipidemic and anti-emetic actions. Ginger is a
strong anti-oxidant substance and may either
mitigate or prevent generation of free radicals. It is
considered a safe herbal medicine with only few
and insignificant adverse/side effects (17).Oxidants
and antioxidants have attracted widespread interest
in nutrition research, biology and medicine. It has
become clear that constant generation of pro-
oxidants, including oxygen free radicals, is an
essential attribute of aerobic life (18). A
disturbance in the pro-oxidant/antioxidant system
has been defined as oxidative stress. Reactive
oxygen species (ROS) are very reactive molecules
ranked as free radicals owing to the presence of
one unpaired electron such as a superoxide ion
(O─2 ), nitrogen oxide (NO) and hydroxyl radical
(HO─). Even though naturally present in the
organism, they are mainly confined to cell
compartments and counterbalanced by natural
antioxidant molecules, such as glutathione,
glutathione peroxidase, superoxide dismutase,
vitamin E and vitamin C, acting as free radical
scavengers (19,20).
Ginger extracts have been extensively studied
for a broad range of biological activities, especially
antioxidant activities (21) found that ginger
significantly lowered lipid per oxidation by
maintaining the activities of the antioxidant
enzymes –super oxide dismutase, catalase and
glutathione peroxides in rats. Cellular damage in
the semen is the result of an improper balance
between ROS generation and scavenging activities.
Excessive ROS production that exceeds critical
levels can overwhelm all antioxidants defense
strategies of spermatozoa and seminal plasma
causing oxidative stress (22, 23).
Therefore, ROS production and total
antioxidant capacity (TAC) can be used as a
marker of oxidative stress in seminal fluid and is
correlated with male infertility. Infertile men with
male factor or idiopathic diagnoses had
significantly lower ROS-TAC scores than controls
(24).
Besides, Said et al (2005) suggested that
abnormal sperm morphology combined with
elevated ROS production may serve as a useful
indicator of potential damage to sperm DNA. On
the other hand, spermatozoa are highly susceptible
to damage by excessive concentrations of ROS due
A
B

The effects of Ginger rhizome on sperms of rat
Iranian Journal of Reproductive Medicine Vol.7. No.1. pp: 7-12, Winter 2009
11
to the high content of polyunsaturated fatty acids
within their plasma membrane. The lipid
peroxidation destroys the structure of lipid matrix
in the membranes of spermatozoa, and it is
associated with loss of motility and impairment of
spermatogenesis (24).
In the present study, administration of
50mg/kg/rar and 100mg/kg/rat ginger for twenty
consecutive days significantly increased sperm
motility and viability in both experimental groups
as compared with the control group (Table I).
These results are supported by the finding of
Aitken et al (1995), who reported that the
conventional basic semen characteristics other than
motility are not obviously influenced by the
oxidative state of semen (25). This increase in
sperm motility of experimental groups in
comparison to control group could be due to the
protective effect of ginger rhizoma administration.
Besid, these productive effects is reflected by the
decrease of malonaldehyde level and increase in
total anti oxidants capacity (Table I).
In according with these results, Hamza et al
(2006) have demonstrated that Z. officinale
treatment increased the activities of testicular
antioxidants enzyme and restore sperm motility of
cisplatin-treated rats. Amr et al (26), reported in
animal models that Z. officinale have protective
effects against cisplatin-induced testicular damage
and oxidative stress in rats. Ginger rhizome
contains a wide variety of both antioxidative (6)
and androgenic activity (27).
The major active phenolic ingredients isolated
from Z. officinale (Zingerone, Gingerdiol,
Zingibrene, gingerols and shogaols) have
antioxidant activity (7, 27, 28). Others reported
that Z. officinale extracts have a potent androgenic
activity in male rats (26). In agreement with these
reports; the present study showed an increase in the
testes weight, serum testosterone levels and
accumulations of sperm in the lumen of
seminiferous tubules (Figure 1).
In conclusion, the present study has
demonstrated that, ginger possess an antioxidant
and androgenic activity in doses of 50 mg/kg/rat
and 100mg/kg/rat and have a useful effects on
spermatogenesis and sperm parameters in rats.
Acknowledgment
The authors are grateful to the staff at Islamic
Azad University Tabriz branch for their help and
support and also to Tabriz Porcina herbal shopping
center.
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