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Citation: Arene Ebube Chinwe, Ajemba Michael Nnaemeka, Ugo Chinemerem Henry, Ojukwu Charles Kenechukwu, Anyadike Ikenna
Kelechi (2022). Anti-Inflammatory Potentials of Aqueous Soursop Pulp Extracts on Induced Benign Prostatic Hyperplasia in Adult Male
Wistar Rats. Saudi J Med Pharm Sci, 8(8): 397-402.
397
Saudi Journal of Medical and Pharmaceutical Sciences
Abbreviated Key Title: Saudi J Med Pharm Sci
ISSN 2413-4929 (Print) | ISSN 2413-4910 (Online)
Scholars Middle East Publishers, Dubai, United Arab Emirates
Journal homepage: https://saudijournals.com
Original Research Article
Nutrition and Dietetics
Anti-Inflammatory Potentials of Aqueous Soursop Pulp Extracts on
Induced Benign Prostatic Hyperplasia in Adult Male Wistar Rats
Arene Ebube Chinwe1*, Ajemba Michael Nnaemeka2, Ugo Chinemerem Henry1, Ojukwu Charles Kenechukwu2,
Anyadike Ikenna Kelechi1
1Department of Nutrition and Dietetics, University of Nigeria, Nsukka, Nsukka - Onitsha Rd, Nsukka, Nigeria
2Faculty of Medicine, Nnamdi Azikiwe University, Along Enugu-Onitsha Expressway, Ifite Road, 420110, Awka, Nigeria
DOI: 10.36348/sjmps.2022.v08i08.004 | Received: 29.06.2022 | Accepted: 02.08.2022 | Published: 10.08.2022
*Corresponding author: Arene Ebube Chinwe
Department of Nutrition and Dietetics, University of Nigeria, Nsukka, Nsukka - Onitsha Rd, Nsukka, Nigeria
Abstract
Background: Benign Prostate Hyperplasia (BPH) is an age associated prostate gland enlargement in men that can lead to
urination difficulty. The exact etiology of BPH is unknown. However, inflammation is a critical factor in the
development of BPH. Soursop as a traditional medicine has anti-inflammatory properties. This study investigated the
anti-inflammatory potentials of soursop pulp extracts on induced benign prostatic hyperplasia (BPH) in adult male wistar
rats. Materials and methods: Twenty-four adult male rats grouped into five were used for the study. BPH was induced
subcutaneously in the inguinal region with testosterone propionate 3mg/kg/day. Acute toxicity test was carried out to
determine the safety of the extract. The rats in group A served as the control group. Rats in group B, C and D were
administered 200mg, 400mg, and 600mg of aqueous soursop extract per kg body weight/day. Biochemical analyses of
the protein specific antigen, albumin, white blood cell count, testosterone, and C-reactive protein were performed after
the trial. Statistical analysis was done using SPSS version 23. Results: Aqueous soursop pulp extract significantly
decreased (p<0.05) the protein specific antigen by 58.87%. The extract at 400mg resulted in a percentage decrease in
white blood cell count by 35.37% and albumin by 31.23 %. The extract at 600mg significantly decreased the testosterone
and C- Reactive Protein by 59.88% and 69.47% respectively. Conclusion: The inflammatory bio-markers (prostate
specific antigen, albumin, white blood cell count, testosterone, and C-reactive protein) studied after treatment revealed
that aqueous soursop pulp extract is promising in the management of benign prostate hyperplasia.
Keywords: Benign prostatic hyperplasia, inflammation, soursop pulp, extract, administered, bio-markers.
Copyright © 2022 The Author(s): This is an open-access article distributed under the terms of the Creative Commons Attribution 4.0 International
License (CC BY-NC 4.0) which permits unrestricted use, distribution, and reproduction in any medium for non-commercial use provided the original
author and source are credited.
INTRODUCTION
Benign prostatic hyperplasia (BPH), is a
histologic diagnosis that refers to the non-cancerous
proliferation of smooth muscle and epithelial cells
within the prostatic transition zone (Auffenberg et al.,
2010). According to recent research, BPH’s stroma or
epithelial proliferation is influenced by chronic
inflammation (Madersbacher et al., 2019). The
prevalence of benign prostate hyperplasia (prostate
enlargement) is increasing in both developed and
developing countries. According to Nickel (2006), BPH
affects more than 42% of men from age 51 to 60, 70%
of men from 61-70 and as many as 90% of men in their
80s and above. As the population of ageing men
increases, BPH has become an important topic of health
concern (Ojewola et al., 2016). Consequently, prostatic
diseases are one of the major causes of enormous
morbidity among men worldwide (Achukwu et al.,
2017). BPH may also be involved in sexual functions
and performance such as painful orgasms, pain in the
testicles, difficulty achieving erection and painful
ejaculation (Propert et al., 2016). In the
Furthermore, there is yet no medicinal cure for
BPH and the related cancers (Doku, 2016).
Management of benign prostate hyperplasia has been
mainly to provide relief-treatment for the symptoms of
the condition. Currently, there is widespread interest in
developing phytotherapeutic agents for the management
of benign prostate hyperplasia due to the perception that
they are safer, more cost-effective and have fewer side
effects than their conventional alternatives (Thompson
et al., 2013).
Arene Ebube Chinwe et al., Saudi J Med Pharm Sci, Aug, 2022; 8(8): 397-402
© 2022 |Published by Scholars Middle East Publishers, Dubai, United Arab Emirates 398
Soursop, botanically known as Annona
muricata L, a tropical fruit trees belonging to the
Annonaceae family. The fruits are large, heart-shaped
and dark green in color. A. muricata fruit consists of
80% water, 18% carbohydrates, 1% protein and small
quantities of vitamins B1, B2, C and dietary fiber (Pier,
2014). The fruit also contains various significant
minerals such as potassium, calcium, sodium, copper,
iron and magnesium. Studies have linked A. muricata to
a variety of anticancer effects including cytotoxicity
and inhibition of proliferation on a variety of cancer cell
(Rady et al., 2018). Due to its anti-proliferative effect
on cancer cell, it is presumed that the plant can be used
in the treatment of enlarged prostate. This study aimed
to determine the anti-inflammatory effects of soursop
pulp extracts on benign prostatic hyperplasia in male
wistar rats.
MATERIALS AND METHODS
Procurement and preparation of samples
Fresh soursop fruits were plucked from a
farmland located at 1 Mbonu Ojike Street, University of
Nigeria, Nsukka, Enugu State. They were identified in
the Harbarium Center of the Department of Plant
Science and Biotechnology, University of Nigeria,
Nsukka. Fresh ripped soursop fruits were washed,
allowed to drain in a colander, cut open with a knife to
scoop out the pulp and the seeds were handpicked. Fifty
grams of the pulp was blended with 100mls of water in
a household blender into a creamy liquid. The content
was sieved with 1-mm mesh to obtain the extract.
Animal procurement
Twenty-four adult male Albino rats were
procured from the animal house of the Department of
Veterinary Medicine, University of Nigeria, Nsukka.
The metabolic cages were washed with detergent and
clean water, disinfected and left to air dry. The rats
were housed individually at standard environmental
conditions of temperature (27 +2oC), humidity (55
+10%) with 12-hour light and dark cycle. All the rats
were fed water and rat chow ad libitum for 4 days for
acclimatization. After this, the rats were allotted to five
groups of six rats each on the basis of body weight with
difference in weights within each group not exceeding
5g.
Induction of BPH
Testosterone propionate (3 mg/kg body
weight) was used to inject subcutaneously in the
inguinal region for 7 days to induce proliferation. This
proliferative stimulation with testosterone propionate
resulted in the development of benign prostatic
hyperplasia in rats (Shin et al., 2012). Successful
induction of BPH was ascertained by testing prostate
specific antigen (PSA) level of the rats on the 9th day.
Experimental Design
The study was conducted for thirty-four days
consisting of four days of acclimatization, seven days
for inducement of benign prostatic hyperplasia (BPH),
two days for establishment of prostatic enlargement and
twenty-one days on experimental diets. The male
Wistar rats after acclimatization for a period of four
days were rested overnight and evenly distributed into
five groups of six rats each. The aqueous soursop pulp
and leaf extract were fed to the rat groups in different
concentrations. Group A containing 6 Prostate enlarged
rats that were not treated, group B containing 6 Prostate
enlarged rats fed with 200mg of aqueous soursop pulp
extract /kg body weight daily, group C containing 6
Prostate enlarged rats fed with 400mg of aqueous
soursop pulp extract / kg body weight daily, group D
containing about 6 rats fed with 600mg of aqueous
soursop pulp extract / kg body weight daily. All the rats
received rat chow and water ad libitum for the period of
the study. The route of administration of the soursop
extracts was oral through the use of cannula.
Blood Sample Collection
Blood were collected twice for the
determination of the presence of prostatic enlargement
prognosis and inflammatory markers parameters; after
BPH induction and after treatment (experiment). The
rats were fasted overnight for ten hours. After fasting,
the media cantus of the eye was punctured. Then drops
of blood that appeared on the skin surface were
collected in a capillary tube while a little pressure was
applied to stop the bleeding. Blood was collected into
EDTA and non-EDTA bottles and centrifuged at 3500
rpm for 10 minutes and the clear serum and plasma
aspirated off respectively for biochemical evaluation.
Inflammatory bio-marker analysis
PSA was determined by using the quantitative
sandwich enzyme immunoassay technique Antibody
specific for PSA according to Nandecha (2010) method.
Albumin was determined with Bromocresol green
(BCG) method by Doumas et al., (1971). Testosterone
was determined using enzyme linked immunosorbent
assay (ELISA) kit. White blood cell count was done
using standard technique as describe by Ramnik (2003).
C-reactive protein (CRP) was determined using Mark
Wener (2007) Nephelometry method.
Acute toxicity (LD50) test
The LD50 of the aqueous soursop pulp extracts
were tested to determine the safety of the extract
according to the guidelines set by Lorke (1983).
Statistical analysis
All data obtained were subjected to statistical
analysis using SPSS version 23.0. All values obtained
were expressed as means and standard deviation and
data were analysed using analysis of variance
(ANOVA) for separation of mean. Duncan Multiple
range test was used to determine which experimental
diet was significantly better in relation to the
parameters tested at 5% probability level (p≤ 0.05).
Arene Ebube Chinwe et al., Saudi J Med Pharm Sci, Aug, 2022; 8(8): 397-402
© 2022 |Published by Scholars Middle East Publishers, Dubai, United Arab Emirates 399
RESULTS AND DISCUSSIONS
Acute Toxicity Results
The acute toxicity result showed that there was
no toxicity/death observed for the soursop pulp at doses
less than or equal to 1000mg/kg body weight after 24
hours. However, the animal survived at higher doses of
1600mg/kg body weight while at 2900 and 5000mg/kg
body weight death was observed. This implies that at
extremely high doses, the sample can be toxic. This
implies that the sample is safe for consumption and is
non-toxic up to dose of 1000mg/kg body weight.
Prostate specific antigen (PSA) of the rats
Treatment with aqueous soursop pulp extract
significantly decreased the PSA levels of the rats in
treated groups when compared to the control group A
(Table 1). Highest percentage decrease in PSA level
occurred with 400mg of the test sample. Testosterone
propionate induced BPH indicates the ameliorative
impact of testosterone propionate induced BPH
(Onyegeme-Okerenta et al., 2022). As a result of
inhibiting 5-reductase, a decrease in PSA is linked to a
reduction in BPH (Sing et al., 1991). The fact that the
PSA level in the negative control group remained high
indicates that the observed decline in PSA in treated
rats was due to the role of aqueous soursop pulp in
reducing the effect of PSA which is one of the factors
that plays a crucial role in higher chance of developing
BPH. This corroborates the findings of Ogbu et al.,
(2020) who discovered acetogenins rich fraction
isolated from soursop plant reduced the levels of PSA
in induced BPH rats.
Table 1: Mean prostate specific antigen (PSA) levels of the rats (miu/ml)
Groups
Baseline
End Value
End value – baseline
% diff.
A
1.53 + 0.28 b
2.32 + 0.32 b
0.79
51.63
B
1.35 + 0.42 b
0.71 + 0.01 a
-0.64
47.41
C
1.30 + 0.42 b
0.61 + 0.06 a
-0.69
58.87
D
1.08 + 0.17 b
0.68 + 0.13 a
-0.40
37.04
Values are expressed as Mean + SD of each rat group (n=6). Mean values with different letters as superscripts across the
column are considered significant at p<0.05.
Baseline= after experiment, End value= after the study.
Group A =Induced and not treated.
Group B = Induced rats fed 200mg/kg bwt of aqueous soursop pulp extract.
Group C= Induced rats fed 400mg/kg bwt of aqueous soursop pulp extract.
Group D= Induced rats fed 600mg/kg bwt of aqueous soursop pulp extract.
White blood cell count of the rats
White blood cells (WBCs) are considered a
valid biomarker of inflammation. Aqueous soursop pulp
extract showed a reduction in WBC count of the rats.
Percentage decline in WBC was observed with
administered doses of soursop pulp extract with
maximum reduction (35.73%) in group treated with
400mg/kg body weight (Table 2). Elevated levels of
WBC have been linked to several chronic diseases
(Libby et al., 2016). This was observed in control group
A. The ability of the test groups to show a decrease in
white blood cell count could be attributed to the anti-
inflammatory properties of the extract.
Table 2: Mean total white blood cell count of the rats (x10 mm3)
Group
Baseline
End value
End value -baseline)
% diff
A
16633.33 + 524.09b
18016.67+1431.67c
1383.34
8.32
B
16166.67 + 1458.31b
12183.33+1062.86 b
-3991.61
24.69↓
C
16650.00 + 926.82b
10700.00+389.87 a
-5950.00
35.73↓
D
13680.00 + 458.3b
10575.00+289.87 a
-3105.00
22.70↓
Values are expressed as Mean + SD of each rat group (n=6). Mean values with different letters as superscripts across the
column are considered significant at p<0.05.
Baseline= after experiment, End value= after the study.
Group A =Induced and not treated.
Group B = Induced rats fed 200mg/kg bwt of aqueous soursop pulp extract.
Group C= Induced rats fed 400mg/kg bwt of aqueous soursop pulp extract.
Group D= Induced rats fed 600mg/kg bwt of aqueous soursop pulp extract.
Albumin levels of the rats
Albumin concentration reflects the nutritional
status of the experimental rats. The control group
showed an increase in albumin level
(hypalbuminaemia) in Table 3. Treatment with aqueous
soursop pulp extract significantly decreased the
albumin levels of the rats in treated groups when
compared to the control group A. Highest percentage
decrease in albumin level occurred with 400mg/kg body
weight while the lowest percentage decrease was
observed in 600mg/kg body weight of the test sample.
Studies have shown that there is always a significant
Arene Ebube Chinwe et al., Saudi J Med Pharm Sci, Aug, 2022; 8(8): 397-402
© 2022 |Published by Scholars Middle East Publishers, Dubai, United Arab Emirates 400
decrease in albumin concentration in BPH condition,
(Kappor, 2012). On the other hand, this study shows that the albumin concentration was properly managed in
rats fed with the extracts.
Table 3: Mean albumin levels of the rats (mg/dl)
Group
Baseline
End value
End value –baseline
% diff
A
6.36 + 0.33 b
8.52+0.62 d
2.16
33.96
B
5.82 + 0.85 b
5.14 + 0.47c
-0.68
11.68
C
5.89 + 0.46 b
4.05 + 0.79 b
-1.84
31.23
D
5.86 + 0.29 b
5.25 + 0.55 b
-0.61
10.40
Values are expressed as Mean + SD of each rat group (n=6). Mean values with different letters as superscripts across the
column are considered significant at p<0.05.
Baseline= after experiment, End value= after the study,
Group A =Induced and not treated.
Group B = Induced rats fed 200mg/kg bwt of aqueous soursop pulp extract.
Group C= Induced rats fed 400mg/kg bwt of aqueous soursop pulp extract.
Group D= Induced rats fed 600mg/kg bwt of aqueous soursop pulp extract.
Testosterone level of the rats
Treatment with aqueous soursop pulp extract
significantly lowered the testosterone level of the rats in
treated groups when compared to the control group B
(Table 4). Highest percentage decrease was observed in
600mg/kg body weight of the test sample. The decline
in testosterone levels in treated groups suggested that its
phytochemical composition of soursop plant may
reduce the effect of the pituitary gland and testosterone
synthesis (Yakubu et al., 2017).
Table 4: Mean testosterone levels of the rats (mg/dl)
Group
Baseline
End value
End value –baseline
% diff
A
0.88+0.03b
2.47+0.45c
1.59
180.68
B
1.54+0.31b
0.96+0.08b
-0.58
37.66↓
C
1.52+0.25b
0.77+0.18b
-0.75
49.34↓
D
8.15+0.81ab
3.27+0.61b
-4.88
59.88↓
Values are expressed as Mean + SD of each rat group (n=6). Mean values with different letters as superscripts across the
column are considered significant at p<0.05.
Baseline= after experiment, End value= after the study.
Group A =Induced and not treated.
Group B = Induced rats fed 200mg/kg bwt of aqueous soursop pulp extract.
Group C= Induced rats fed 400mg/kg bwt of aqueous soursop pulp extract.
Group D= Induced rats fed 600mg/kg bwt of aqueous soursop pulp extract.
Table 5 shows the C-Reactive Protein (CRP)
levels of the rats after induction and after treatment.
CRP is a non-specific marker of inflammation and it
may reflect the presence of inflammation in urologic
pathways that could lead to BPH (Nnatuanya et al.,
2022). Treatment with aqueous soursop pulp extract
significantly lowered the CRP level of the rats in the
treated groups when compared to the control group A.
Highest percentage decrease was observed in 600mg/kg
body weight of the test sample. This indicates that CRP
was controlled because its decrease could be related to
an effective management of the implication of BPH in
the treated animals.
Table 5: Mean C- reactive protein (CRP) levels of the rats (µg/Ml)
Group
Baseline)
End value
End value-baseline
Percentage diff (%)
A
8.44 + 0.21b
8.89 + 0.55d
0.45
5.33
B
8.89 + 0.90b
4.34 + 0.21c
-4.55
51.18↓
C
8.54 + 0.90b
2.89 + 0.40c
-5.65
66.16↓
D
8.55 + 0.70b
2.61 + 0.53c
-5.94
69.47↓
Values are expressed as Mean + SD of each rat group (n=6). Mean values with different letters as superscripts across the
column are considered significant at p<0.05.
Baseline= after experiment, End value= after the study.
Group A =Induced and not treated.
Group B = Induced rats fed 200mg/kg bwt of aqueous soursop pulp extract.
Group C= Induced rats fed 400mg/kg bwt of aqueous soursop pulp extract.
Group D= Induced rats fed 600mg/kg bwt of aqueous soursop pulp extract.
Arene Ebube Chinwe et al., Saudi J Med Pharm Sci, Aug, 2022; 8(8): 397-402
© 2022 |Published by Scholars Middle East Publishers, Dubai, United Arab Emirates 401
CONCLUSION
The findings of this study indicates that
aqueous soursop pulp extract have beneficial effect on
the inflammatory bio-markers of enlarged prostate. The
ability of the extracts to have ameliorative effect on
induced prostate enlargement makes them potentially
useful in the management of BPH. Because the majority
of previous studies were focused on the biological
activities of the leaf extract, additional studies are
required to isolate the active components responsible
for the observed effects in the fruit extract.
Acknowledgements
The authors sincerely thank Professor U.A.
Onyechi of the Department of Nutrition and Dietetics,
University of Nigeria, Nsukka for her constructive
criticism throughout the course of this work and to Mr.
A.I. Agbo of the Department of Veterinary Medicine,
University of Nigeria, Nsukka for his technical
assistance.
Declaration of Conflict of Interests
The authors declared no potential conflicts of
interests with respect to the research.
Funding: The authors received no financial support for
the research and/or publication of this article.
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