"" Modulating Role of <em>Panax Ginseng</em> in Experimentally Induced Benign Prostatic Hyperplasia in Adult Male Albino Rats

Research Article

Austin J Anat. 2015;2(1): 1030.

Modulating Role of Panax Ginseng in Experimentally Induced Benign Prostatic Hyperplasia in Adult Male Albino Rats

*Abeer El-Said El-Mehi and Neveen Mohamed El-Sherif

Department of Anatomy and Embryology, Menoufiya University, Egypt

*Corresponding author: Abeer El-Said El-Mehi, Department of Anatomy and Embryology, Menoufiya University, Egypt.

Received: February 04, 2015; Accepted: March 10, 2015 Published: March 13, 2015

Abstract

Benign Prostatic Hyperplasia (BPH) is a common non-malignant disease in elderly men. It has a significant impact on the quality of life. Ginseng is one of the most commonly used herbal medicines with a wide range of beneficial effects. The aim of this study was to investigate the beneficial effects of ginseng on experimentally induced benign prostatic hyperplasia in adult male albino rat. Twenty four (3-month old) male albino rats, with average weight 180-200 gm, were assigned into three groups: Group I (control group), Group II (ginseng treated) and Group III (BPH). The latter group was then subdivided into 2 groups; BPH+basal diet and BPH+ ginseng. BPH was induced by testosterone propionate 7.5 mg/kg body weight/day intramuscularly for 10 days. Panax ginseng was administered at a dose of 10 mg/kg body weight /day orally by gastric tube for 4 weeks. Induction of BPH resulted in significantly increased prostatic weight and increased Dihydrotestosterone (DHT) level in prostate. The histopathological features showed evidence of hyperplasia and inflammation. Quantitative immunohistochemical assessment showed significant upregulation of a-Smooth muscle actin (a-SMA) and Tumor necrosis factor-a (TNF-a). On the other hand, there was significant down regulation of transforming growth factor-β receptor1 (TGFΒRI) and Caspase-3. Panax ginseng treatment significantly ameliorated the changes associated. Panax ginseng treatment inhibits prostatic hyperplasia by reducing epithelial cell proliferation and smooth muscle hyperplasia that may be attributed to potential anti-inflammatory, antiproliferative, anti-oxidant and apoptotic effects. This provides a new insight into the management of BPH using natural agents.

Keywords: Panax ginseng; Benign prostatic hyperplasia; Immunohistochemistry

Introduction

The prostate is a key gland in the sexual physiology of male mammals. Its location in the reproductive tract influences several vital functions such as those related to micturition, seminal emission, and ejaculation [1]. The general pattern of the prostate gland is common to all rodents and human [2]. The ventral lobe as well as the lateral lobe of rat prostate is the most homologous to human prostate, although the ventral one is an essential target for prostatic hyperplasia [3].

Benign Prostatic Hyperplasia (BPH) is a urological disorder characterized by the noncancerous enlargement of the prostate. Problems associated with BPH shows a prevalence of 30% to 60% in menolder than 60 years and 80% in men by age 80 years [4]. As the prostate enlarges, it puts pressure on the urethra and causes the muscles around the urethra to contract leading to a weak urinary stream, incomplete bladder emptying, nocturia, dysuria, bladder outlet obstruction and recurrent infections [5].

BPH is characterized by proliferation of the cellular elements of the prostate. Glandular enlargement may result from an imbalance between prostate cell growth and apoptosis. This imbalance is complex and influenced by factors that stimulate proliferation and minimize cell apoptosis such as growth factors, cytokines and steroid hormones [6,7].

Testosterone produced through hypothalamic-pituitarygonadal axis activity is believed to regulate prostate growth [8]. The enzyme 5a-reductase, found in prostatic cells, catalyzes testosterone conversion into the potent androgen Dihydrotestosterone (DHT). DHT can stimulate a variety of growth factors that accelerate hyperplasia of the stromal and epithelial cells of the prostate resulting in prostatic enlargement. Inflammation can play an important role in BPH. The more the inflammation, the larger the prostate will be [9].

At present, pharmacotherapy becomes the modality of choice for BPH treatment with a shift from surgical treatment. The main drugs used for the management of BHP symptoms include a-blockers and 5a-reductase inhibitors. However, these drugs are limited because of their side effects, including decreased libido, ejaculatory or erectile dysfunction [10].

Due to these risks, natural products appear to have important role in the treatment of BPH. Ginseng (the root of Panax ginseng) is a widely used herbal medicine [11]. Ginseng roots contain multiple active constituents, ginsenosides being the major biologically active compounds [12]. The potential therapeutic effects of ginseng have been attributed to its immunostimulatory, antioxidant, vasorelaxant, anti-neoplastic and anti-inflammatory activities [13]. With respect to the mechanism responsible for the anticancer effects of ginseng, most investigations have focused on cell growth arrest or apoptosis [14]. As BPH is attributable to the uncontrolled growth, we investigate whether ginseng prevents BPH by controlling prostate cell proliferation and apoptosis.

Materials and Methods

Animals

Twenty four male Wistar albino rats (3 months old, weighing 180–200 g) were obtained and housed in the animal house of Faculty of Medicine, Menoufia University, Egypt. Animals of each group were housed in separate hygienic cages at the room temperature. The animals received a standard diet for rodents and allowed free access to water. All experimental procedures were conducted with approval of the Research Ethics Committee, Faculty of Medicine, Menoufia University.

Drugs / Material

Experimental design

Animals were divided into three groups:

Group I (control group): consisted of six rats.

Group II (ginseng treated group) (six rats) received basal diet for 10 days followed by panax ginseng, at a dose of 10 mg/kg body weight (dissolved in distilled water), orally by a gastric tube once daily for 4 weeks [15].

Group III (12 rats) received testosterone propionate 7.5 mg/kg body weight/day intramuscularly for 10 days to induce prostatic hyperplasia [16]. This group was then subdivided into two equal subgroups:

Subgroup IIIa: received ordinary diet for 4 weeks.

Subgroup IIIb (testosterone+ginseng treated group): Received panax ginseng, at the same dose mentioned before, for 4 weeks.

At the end of each experimental period, animals were fasted overnight. Rats were killed by cervical dislocation under ether anesthesia. The prostatic gland was excised, weighed and divided into two halves. One half was fixed in Bouin’s solution for 48 hours and processed to prepare paraffin sections. The other half was stored at -80C in liquid nitrogen for hormonal assay.

Tissue biochemical study

Prostatic tissue levels of DHT were determined using an Enzyme-Linked Immunosorbent Assay (ELISA) kit according to the manufacturer’s instructions (ALPCO Diagnostics, Salem, NH, USA). The absorbance was measured at 450 nm using a microplate ELISA reader (Bio-Rad Laboratories, Inc.). Values were expressed per mg protein for the prostate.

Histological and immunohistochemical studies

Paraffin sections were prepared with a thickness of 5 microns, mounted on glass slides and stained with H&E and Mallory’s trichrome technique [17]. In each slide, the ventral lobe of the prostate was chosen, according to its histological criteria, for examination and description.

For immunohistochemical staining, Sections were rinsed with PBS, blocked for 30 min in 0.1% H2O2 as inhibitor for endogenous peroxidase activity. After rinsing in PBS, sections were incubated for 60 min in blocking solution (10% normal goat serum) at Room Temperature (RT) (22oC). The sections were then incubated with the primary antibody. Sections were rinsed with PBS, followed by 20 min of incubation at RT with secondary biotinylated antibody. After rinsing the sections in PBS, enzyme conjugate “Streptavidin- Horseradish peroxidase” solution was applied to the sections for 10 min. Secondary antibody binding was visualized using 3, 3-Diaminobenzoic Acid (DAB) dissolved in PBS with the addition of H2O2 to a concentration of 0.03% immediately before use. Finally, sections were PBS rinsed and counterstaining of slides was done using two drops of hemotoxylin. Slides were washed in distilled water until the sections turned blue. Finally, slides were dehydrated in ascending grades of ethanol (70%, 95%, and 100%) for 5 min each and were cleared in xylene and finally coverslipped using histomount mounting solution [18]. Sections were examined with an Olympus light microscope (BX51TF; Olympus, Tokyo, Japan) and photographed.

Quantitative assessment and statistical analysis

Data were obtained using “Leica Qwin-C500” image analyzer computer system (England). The following parameters were measured:

For each parameter, 10 non overlapping fields for every specimen, at magnification X 400, were examined.

Statistical analysis

The data obtained were presented as mean ± SD. Data was statistically analyzed using one-way ANOVA followed by Tukey’s post-test. All statistical analyses were performed using Prism version 4.03 for Windows (GraphPad software Inc., San Diego, California, USA). P Value =0.05 was considered statistically significant [19].

Results

There was no significant difference between Group I (control) and Group II (ginseng treated) rats in all the outcomes at each time point used in the study; therefore, these two groups were pooled in one group (control).

Gross observations

There were no deaths in any of the groups. Testosterone treated group revealed prostatic enlargement by inspection.

Prostatic weight

The mean prostatic weight of testosterone treated rat was significantly higher than that of the control group. However, ginseng treated group was significantly lower than that of testosterone treated rats. No significant difference was found between ginseng treated and control groups (Graph 1).

Measurement of DHT level in prostate

The DHT level in the prostate of testosterone treated group was significantly higher than in controls. However, prostatic DHT level in the ginseng treated group was significantly lower than in testosterone treated group to become non significant from control group (Graph 2).

Histological results

H&E stained sections: Sections of control rats showed that the prostatic parenchyma was composed of packed acini of different sizes. Acini were lined with simple columnar cells with basal nuclei and a small number of epithelial papillary folds. The acini were separated by minimal fibromuscular stroma. Some acini contained homogenous acidophilic secretion (Figure 1a &1b).