HOW LOCAL HERB PROTECTS ALCOHOL-INDUCED KIDNEY DAMAGE

A local Nigerian plant could provide the
source of a novel drug for alcohol induced
kidney damage and diabetes.
NIGERIAN researchers have isolated a local
plant, Abrus precatorious, which seed
extract has some anti-diabetic properties
similar to that of a conventional diabetic
drug and could protect the kidney against
alcohol-induced damage.
The researchers from the department of
human anatomy, Faculty of Basic Medical
Sciences, Niger Delta University, Bayelsa
State; and the Department of Anatomical
Pathology, University of Port-Harcourt
Teaching Hospital Port-Harcourt, Rivers
State, concluded: “The results of this study
strongly indicate that the aqueous extract
of the seed of Abrus precatorius has
protective effect on alcohol-induced renal
injury and that this effect is related to the
attenuation of alcohol- mediated lipid
peroxidation of renal parenchymal cells.
Lipid peroxidation refers to the oxidative
degradation of lipids. It is the process in
which free radicals “steal” electrons from
the lipids in cell membranes, resulting in cell
damage.
Parenchymal cells are the main functional
cells of an organ or tissue - as distinguished
from non-parenchymal cells (frequently
referred to as stromal cells) that provide
supporting structural elements such as cells
forming the connective tissue, blood
vessels, and nerves.
The study was published in European
Journal of Scientific Research.
Commonly called jequirity (from a Brazilian
name); crab’s eyes (the seeds); bird’s eye
(the seeds); prayer beads (the seeds); lucky
bean (the seeds); Indian liquorice, or wild
liquorice (the root), Abrus precatorious
belongs to the family Leguminosae-
Papilionoideae. In Nigeria, it is omisinmisin
in Yoruba, and empo in Esan.
Previous studies have shown that the leaf
extract of Abrus precatorius could be
applied on the eyes for cataract and
chewed for asthma.
According to The useful plants of west
tropical Africa, Vol. 3, Abrus precatorious is a
twining herbaceous, sub-woody, lianous
plant with stems up to 1?5 cm diameter; of
thickets, clearings, secondary jungle of all
types and galleried forest in slightly damp
sites, throughout the region from Senegal to
Nigeria and Fernando Po.
The study investigated the renal protective
activities of the seed extract of Abrus
precatorius following alcohol induced renal
damage in adult male Sprague dawley
wister rats. Experimental rats were divided
into six groups of five rats per group. Renal
damage was induced with alcohol (1.6g/kg)
orally. The treated group received the crude
extract (200mg/kg) orally in addition to
alcohol for six weeks, with normal feeds
and water ad libitum (water as desired).
Histological studies, biochemical indicators
of renal function and thiobarbituric acid-
reactive substances, as markers of lipid
peroxidation, were thereafter determined.
Thiobarbituric Acid Reactive Substances
(TBARS) is a well-established method for
screening and monitoring lipid
peroxidation.
The researchers wrote: “Oral administration
of alcohol caused significant elevation of
serum potassium and sodium levels as well
as creatinine and malondialdehyde levels.
There were structural alterations in renal
tubules, glomerular infiltration by chronic
inflammatory cells.
“Concurrent administration of same doses
of alcohol and seed extract of Abrus
precatorius resulted in a suppression of
alcohol-induced renal injury. Measurement
of malondialdehyde level indicated that this
effect is related to the attenuation of
alcohol-induced lipid peroxidation by the
seed extract. We conclude that the seed
extract of abrus precatorius could protect
the kidney against alcohol-induced
parenchymal injury.”
Creatinine is a chemical waste molecule that
is generated from muscle metabolism.
Creatinine is produced from creatine, a
molecule of major importance for energy
production in muscles. Approximately two
per cent of the body’s creatine is converted
to creatinine every day. . Creatinine is
transported through the bloodstream to the
kidneys. The kidneys filter out most of the
creatinine and dispose of it in the urine.
Although it is a waste, creatinine serves a
vital diagnostic function. Creatinine has
been found to be a fairly reliable indicator
of kidney function. As the kidneys become
impaired the creatinine will rise. Abnormally
high levels of creatinine thus warn of
possible malfunction or failure of the
kidneys, sometimes even before a patient
reports any symptoms. It is for this reason
that standard blood and urine tests
routinely check the amount of creatinine in
the blood.
Malondialdehyde level is the end product of
lipid peroxidation and is used as a marker
of free radical-induced tissue damage.
Glomerular filtration rate (GFR) is a test used
to check how well the kidneys are working.
Specifically, it estimates how much blood
passes through the tiny filters in the
kidneys, called glomeruli, each minute.
The researchers said the finding is
supportive evidence that the seed extract
of Abrus precatorius has protective effect
against alcohol induced renal injury and
that this effect may be related to a
reduction in alcohol-induced lipid
peroxidation. ß
The active metabolites in the seed of Abrus
precatorius include abrin, abrus agglutinin,
glycyrrhizin gallic acid, trigonelline,
precatorine and lipolytic enzymes. Glucine,
Coumestrans, resin asparagines and sterols,
among others, have also been
demonstrated. Gallic acid, glycyrrhizin and
trigonelline are potent antioxidants. These
metabolites may account for the ability of
the seed extract of Abrus precatorius to
attenuate alcohol induced lipid peroxidation
of renal cell membrane vivo.
The seed extract of Abrus precatorius have
also been shown to possess other
pharmacologic properties. It was shown to
have anti-fertility effect. Researchers have
also demonstrated ureterotonic effect and
antidiarrhoeal effect. More recently,
Adelowotan et al. demonstrated
antimicrobial activities with the aqueous
extract of the seed of Abrus precatorius.
The researchers added: “Although Abrus
precatorius has been shown to be stable in
the gastrointestinal tract, the presence of
toxic lectins in its seed limits its
pharmacologic utility. Abrin and Abrin
agglutinin are type IV ribosome inactivating
proteins that inhibit protein synthesis in
eukaryotes and induce apoptosis.
“Concurrent administration of vitamin E, a
potent antioxidant, with alcohol and Abrus
precatorius seed extract did not produce
enhanced antioxidant effect in this study.
This can be explained by the diversity of
the mechanisms by which antioxidants
restrict lipid peroxidation by free radicals.
Denisov and Azatyam explained that the co-
administration of two inhibitors of free
radicals to an oxidized hydrocarbon or
other substances may exhibit a net additive,
synergistic or antagonistic effect. It is not
unlikely therefore that a net antagonistic
effect was the outcome following
concurrent administration of the seed
extract of Abrus precatorius, alcohol and
vitamin E.”
Another study published in Journal of
Applied Sciences and Environmental
Management has shown that the
chloroform – methanol extract of Abrus
precatorius seed has some anti-diabetic
properties similar to that of chlopropamide
(a conventional diabetic drug).
The researchers from the Departments of
Biochemistry, University of Port Harcourt,
Rivers State, and University of Nigeria,
Nsukka, Enugu State, studied the anti-
diabetic effect of chloroform – methanol
extract of Abrus precatorious seed, in
alloxan diabetic rabbits.
The effect was compared to that of
chlorpropamide – a known anti-diabetic
drug in the class of sulphonylurea and a
control group that received normal saline
instead of the extract. Normal blood glucose
levels drawn before the alloxan injection
were 127.80 ± 2.55, 114.30 ± 4.17 and
123.60 ± 1.47 mg/100ml for chloroform –
methanol, chlorpropamide and control
respectively. When 50mg / kg body weight
of chloroform – methanol, chlorpropamide
and 5ml of normal saline for control were
given orally, blood glucose levels decreased
in chloroform – methanol and
chlorpropamide groups of alloxan diabetic
rabbits but not in control.
The percentage reduction of blood glucose
of chlorpropamide was 13.8, 32.3, 60.3,
53.5, 46.8, 46.3 and 46.2 after 05, 10, 20,
30, 40, 60 and 68 hours of oral
administration respectively, while that of
chloroform – methanol extract was 42.9,
58.7, 67.4, 69.1, 67.9, 56.6 and 51.8 per cent
respectively. The peak percentage reduction
was 69.1 per cent after 30 hours and 61.3
per cent after 20 hours, for chloroform –
methanol extract and chlorpropamide
respectively.
The researchers concluded: “This study
therefore has shown that the chloroform –
methanol extract of Abrus precatorius seed
has some anti-diabetic properties similar to
that of chlopropamide. This is shown in
their similar percentage reduction in blood
glucose level.”