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Eating soursop to beat diabetes, cancer
Researchers have shown that a meal of soursop could be the cure for
diabetes, heart disease, cancer, and diarrhea. CHUKWUMA MUANYA reports.
THEY are known for their succulent white endocarp. They are replete in
southern Nigeria. The fruit-pulp is soft with an agreeably sour flavour.
It is usually eaten raw but unfortunately contains a quantity of fibre. It
may be more acceptable after some preparation, that is either as juice,
ice-cream, jellies but not jams.
Commonly called Soursop, Annona muricata is a plant, which belongs to the
family Annonaceae. H. M. Burkill in the Useful Plants of West Tropical
Africa described the Soursop plant as "a small tree attaining a height of
about eight metre. A native of tropical America, but now widespread in the
tropics, it is thought to have reached Africa (Angola) by 1686. The trunk
and timber do not appear to have any particular uses."
Soursop is a medicinal plant that has been used as a natural remedy for a
variety of illnesses. Several studies by different researchers
demonstrated that the bark as well as the leaves has anti-hypertensive,
vasodilator, anti-spasmodic (smooth muscle relaxant) and cardio depressant
(slowing of heart rate) activities in animals.
Researchers had re-verified Soursop leaf's hypotensive (reduce blood
pressure) properties in rats. Other properties and actions of Soursop
documented by traditional uses include its use as anti-cancerous,
anti-diabetes, anti-bacterial, anti-fungal, anti-malarial, anti-mutagenic
(cellular protector), emetic (induce vomiting), anti-convulsant, sedative
(induces sleep), insecticidal and uterine stimulant (helps in childbirth).
It is also believed to be a digestive stimulant, antiviral, cardio tonic
(tones, balances and strengthens the heart), febrifuge (cures fever),
nerviness (balances/calms the nerves), vermifuge (expels worms),
pediculocide (kills lice) and as an analgesic (pain-reliever).
Researchers have confirmed the anti-viral activity of ethanolic extracts
of Soursop against Herpes simplex virus.
Extracts of Soursop have been shown to have anti-parasitic,
anti-rheumatic, astringent, anti-leishmanial and cytotoxic effects.
Soursop has also been shown to be effective against Multi-Drug Resistant (MDR)
cancer cell lines. Extracts of Soursop were also shown to be effective
against the cancer cell line U973, and hematoma cell lines in-vitro.
Extracts were also shown to be lethal to the fresh water mollusk,
Biomphalaria glabrata, which act as a host for the parasitic worm
Schistosoma mansoni.
But recent studies have described how extracts of Soursop reduces blood
sugar in diabetics by improving insulin production, improves
cardiovascular health by reducing blood fats, treat drug resistant cancer,
stop diarrhea in children, among others.
Nigerian researchers have evaluated the effects of methanolic extract of
Soursop leaves on the pancreatic islet cells of streptozotocin induced-
diabetic rats. The results of the study indicated that Soursop extract
treatment decreased the blood glucose concentration of diabetic rats due
to the regeneration/proliferation in the pancreatic Beta cells ( -cells).
The pancreas is a gland organ in the digestive and endocrine system of
vertebrates. It is both an endocrine gland producing several important
hormones, including insulin, glucagon and somatostatin, as well as an
exocrine gland, secreting pancreatic juice containing digestive enzymes
that pass to the small intestine. These enzymes help in the further
breakdown of the carbohydrates, protein, and fat in the chyme.
Beta cells (beta-cells, _-cells) are a type of cell in the pancreas in
areas called the islets of Langerhans. They make up 65-80 per cent of the
cells in the islets. Beta cells make and release insulin, a hormone that
controls the level of glucose in the blood.
Streptozotocin (Streptozocin, STZ, Zanosar) is a naturally occurring
chemical that is particularly toxic to the insulin-producing beta cells of
the pancreas in mammals. It is used in medicine for treating certain
cancers of the Islets of Langerhans and used in medical research to
produce an animal model for Type 2 diabetes.
Streptozotocin-induced hyperglycemia in rats is considered a good model
for the preliminary screening of agents active against Type 2 diabetes and
is widely used. Generally, destruction of _-cells starts three days after
STZ administration and reaches its peak at three to four weeks in rats.
Streptozotocin-induced diabetes in laboratory animals has been widely used
for research on diabetes and its long-term complications.
The study titled "Effects Of Annona muricata (Soursop) On The Morphology
Of Pancreatic Islet Cells Of Experimentally-Induced Diabetic Wistar Rats"
was published in Internet Journal of Alternative Medicine, 2008 Volume 5
Number 2 by David Olawale Adeyemi, Omobola Aderibigbe Komolafe, Stephen
Olarinde Adewole, Efere Martins Obuotor, Thomas Kehinde Adenowo.
Soursop has been found to contain numerous bioactive compounds useful for
the management of various ailments including Diabetes Mellitus (DM), Type
2 diabetes, in folkloric medicine. The management of DM depends on
continuous hypoglycemic therapy, which may not be consistently adhered to
by the patient.
The researchers; therefore, investigated whether or not extracts of
Soursop could provide lasting hypoglycemic control through regeneration of
the destroyed - cells of the pancreatic islets of experimentally induced
diabetic Wistar rats.
The result of this study demonstrated that Soursop possesses anti-hyperlipidemic
activities. Hyperlipidemia, hyperlipoproteinemia, dyslipidemia or
hyperlipidaemia (British English) is the presence of raised or abnormal
levels of lipids (fatty molecules) and/or lipoproteins in the blood.
The researchers from Obafemi Awolowo University (OAU) Ile-Ife, Osun State,
include David Olawale Adeyemi, Omobola Aderibigbe Komolafe, Stephen
Olarinde Adewole all of the Department of Anatomy and Cell Biology and
Efere Martins Obuotor of Department of Biochemistry.
The study was published in The Internet Journal of Alternative Medicine,
2009 Volume 7 Number 1.
30 adult Wistar rats were randomly assigned into three groups (A, B and C)
of ten rats each. Group A was the control, Group B was untreated diabetic
group and group C was Soursop-treated group.
DM was experimentally induced in groups B and C by a single
intra-peritoneal injection of 80mg/kg streptozotocin dissolved in 0.1M
citrate buffer. Group A rats were intraperitoneally injected with
equivalent volume of citrate buffer.
Daily intra peritoneal injection of 100mg/kg
Soursop was administered to group C rats for two weeks. The rats were
sacrificed and the pancreas were removed and fixed in Bouins fluid. The
tissues were processed for paraffin embedding and sections of 5µm
thickness were produced and stained. Histopathological examination of the
stained sections showed regeneration _-cells of islets of pancreas of
Soursop-treated rats when compared to untreated diabetic group of rats.
The researchers concluded: "The result of this present study indicated
that decreased in the blood glucose concentration of diabetic rats by
Soursop treatment is due to the regeneration/proliferation in the
pancreatic _-cells."
Nigerian researchers have also demonstrated the effects of methanolic
extracts of Soursop on serum lipid profile changes in
experimentally-induced diabetic Wistar rats with view to elucidate its
possible effects on cardiovascular diseases induced by hyperglycemia.
Diabetes mellitus (DM) is associated with an increased risk of thrombotic,
atherosclerotic and cardiovascular disease. Hyperlipidemia is metabolic
complication of both clinical and experimental diabetes. Low-density
lipoprotein (LDL)- 'bad cholesterol'- in diabetic patients leads to
abnormal metabolism and is associated with increase in very low-density
lipoprotein (VLDL) secretion and impaired VLDL catabolism. Ultimately this
leads to atherosclerotic plaque. A number of known factors for coronary
artery disease such as hypertension, obesity and dyslipidemia/hyperlipidemia
are more common in diabetics than in the general population.
The World Health Organisation (WHO) predicts that the number of cases
worldwide for diabetes, now as of 171 million, will touch 366 million or
more by the year 2030.
Patients with DM are more likely to develop microvascular and
macrovascular complications than the non-diabetic population. Dyslipidemia/hyperlipidemia
is a frequent complication of DM and is characterised by low levels of
high-density lipoprotein (HDL)- 'good cholesterol'- and high levels of
low-density lipoprotein (LDL) and triglyceride (TG). Triglycerides, as
major components of (VLDL), play an important role in metabolism as energy
sources and transporters of dietary fat.
30 adult Wistar rats were randomly assigned into three groups (A, B and C)
of ten rats each. Group A was the control, Group B was untreated diabetic
group and group C was Soursop-treated group. The changes in the serum
lipid profiles were monitored in all the animals four weeks before the
commencement of the experiment and throughout the experimental period.
Diabetes mellitus was induced in groups B and C by a single
intra-peritoneal injection of 80mg/kg streptozotocin dissolved in 0.1M
citrate buffer. The control group was intraperitoneally injected with
equivalent volume of citrate buffer and all the animals were monitored for
another four weeks. Daily intra peritoneal injection of 100mg/kg Soursop
was administered to group C rats for two weeks and the animals were
monitored for another two weeks.
The data obtained were analysed with descriptive and inferential
statistics. The result of the serum lipid analysis showed a significant
reduction in the serum total cholesterol, triglyceride, low-density
lipoprotein cholesterol and very low-density lipoprotein cholesterol, and
a significant increase in the serum high-density lipoprotein cholesterol
and antiatherogenic index of Soursop-treated group when compared to
untreated diabetic group of rats. Atherogenesis is the process of forming
atheromas, plaques in the inner lining (the intima) of arteries.
The researchers concluded: "The result of this present study clearly shows
that Annona muricata has a lipid lowering effects on serum triglycerides,
total cholesterol and low-density lipoprotein cholesterol of STZ induced
diabetic rats. A. muricata treatment also increase the serum level of
High-density lipoprotein cholesterol termed 'good cholesterol'. There is a
substantial evidence that lowering the total cholesterol, particularly LDL
level will lead to a reduction in the incidence of coronary heart disease
which is still the leading cause of death in diabetic patients."
Nigerian researchers have used the fruit juice of Soursop to stop diarrhea
in children and adults. The study, titled "Use of Soursop and Sweetsop
Juice in the Management of Diarrhoea in Children", was published in
Journal Diarrhoeal Disease Resident by Dr. Ifeoma B. Enweani of the
Department of Microbiology Faculty of Natural Sciences, Edo State
University, Ekpoma, Edo State.
The juice was administered onto 25 children aged six - 20 months and five
adults with acute watery diarrhea. Children with prolonged diarrhea,
malnutrition, or other major systemic illnesses were excluded. Five mL of
the juice was administered on to the patients three times daily for up to
72 hours.
The fruit juice was able to resolve the diarrheic condition at 48 hours.
This conforms to the report that at 48 hours 42 per cent of the diarrheic
patients treated with smectite were free from diarrhea. Zinc available in
the juice had been reported to bring about significant reduction in
intestinal fluid loss. This suggests that Soursop juice can be used as a
complementary source for Oral Rehydration Therapy (ORT) in the management
of diarrhea in children and adults. This could reduce morbidity and
mortality rate in children, specially in the developing nations.
Many active compounds and chemicals have been found in Soursop, as
scientists have been studying its properties since the 1940s. Most of the
research on Soursop focuses on a novel set of chemicals called Annonaceous
acetogenins. Soursop produces these natural compounds in its leaf and
stem, bark, and fruit seeds.
Three separate research groups have confirmed that
these chemicals have significant anti-tumorous properties and selective
toxicity against various types of cancer cells (without harming
healthy cells) publishing eight clinical studies on their
findings. Many of the acetogenins have demonstrated selective
toxicity to tumour cells at very low dosages-as little as one part per
million. Four studies were published in 1998, which further specify
the chemicals and acetogenins in Soursop, which are demonstrating the
strongest anti-cancerous, antitumorous, and antiviral properties.
In a 1997 clinical study, novel alkaloids found in
Soursop fruit exhibited antidepressive effects in animals.
Researchers in Taiwan reported in 2003 that the main Soursop acetogenin,
annonacin, was highly toxic to ovarian, cervical, breast,
bladder and skin cancer cell lines at very low dosages
saying; " . . . annonacin is a promising anti-cancer agent and worthy of
further animal studies and, we would hope, clinical trials.
According to the Useful Plants of West Tropical Africa, the fruit contains
over 11 per cent sugar, mostly glucose and fructose. It is deficient in
calcium, phosphorus and vitamin A but very rich in vitamins B and C. |