Local plant show promise indiabetes, HIV/AIDS

Extracts of a local plant have shown great
promise in boosting immune functions
and controlling blood glucose or managing
diabetes.
RESEARCHERS have validated the folklore
uses of a local plant, Phyllanthus niruri, in
boosting the immune system against
infectious diseases such as Human Immuno-
deficiency Virus (HIV)/Acquired Immune
Deficiency Syndrome (AIDS) and lowering of
sugar and cholesterol levels, and in the
prevention of heart diseases.
Phyllanthus niruri also known as “Chanca
pledra” belongs to the family
Euphorbiaceae. It is known as Enyikwonwa
in Ibo of the southeastern part of the
country.
Phyllanthus niruri is similar to Phyllanthus
amarus, which also belongs to the plant
family Euphorbiaceae, called oyomokeso
amanke edem in Efik, geeron-tsuntsaayee
(bird ’s millet) in Hausa, ngwu in Ibo, ehin
olobe and yin-olobe in Yoruba.
The first study titled “The Effects of
Phyllanthus niruri Aqueous Extract on the
Activation of Murine Lymphocytes and Bone
Marrow-Derived Macrophages ” was
published in Immunological Investigations.
Murine relates to a rodent of the family
Muridae or subfamily Murinae, including
rats and mice. A lymphocyte is a type of
white blood cell in the vertebrate immune
system. It has two types B and T
lymphocytes. T lymphocytes play a central
role in immune responses, carrying out a
number of effector and regulatory
functions. They represent the CD4 and CD8
count, which are markers for the immune
system.
Bone marrow derived macrophage (BMDM)
refers to a white blood cell that is generated
in a research laboratory from mammalian
bone marrow.
The researchers wrote: “Phyllanthus niruri
is acclaimed world-wide for its versatile
ethno-medicinal uses. It features in recipes
used by some herbalists to manage
different diseases, including claims of
efficacy against many life-threatening
infections, such as HIV/AIDS and hepatitis. In
order to understand the mechanisms and
the involvement of the immune system in
mediating these activities, the effects of the
aqueous extract of P. niruri on the
activation of murine lymphocytes and
macrophages were investigated.
“The study showed that the extract of P.
niruri is a potent murine lymphocytes
mitogen, inducing significant increases in
the expression of surface activation maker
(CD69) and proliferation of B and T
lymphocytes.
The production of interferon (IFN) and
interleukine-4 (IL-4) by P. niruri extract-
stimulated naïve splenocytes (the different
white blood cell types situated in the spleen
or purified from splenic tissue) cultures was
also significantly increased in a
concentration-dependent manner. ”
A mitogen is a chemical substance that
encourages a cell to commence cell division,
triggering mitosis. CD69 (Cluster of
Differentiation 69) is a human
transmembrane C-Type lectin protein
encoded by the CD69 gene. The activation
of T lymphocytes, both in vivo and in vitro,
induces expression of CD69.
The term “cytokine” has been used to refer
to the immuno-modulating agents, such as
interleukins and interferons. IFN-?, or type II
interferon, is a cytokine that is critical for
innate and adaptive immunity against viral
and intracellular bacterial infections and for
tumor control.
IL-4 is a cytokine that induces
differentiation of naive helper T cells. It has
many biological roles, including the
stimulation of activated B-cell and T-cell
proliferation.
The researchers concluded: “Various indices
of activation and functions murine bone
marrow-derived macrophages were
significantly enhanced by pre-treatment
with the extract, including phagocytosis,
lysosomal enzymes activity, and Tumour
Necrosis Factor-alpha (TNF) release.
Phyllanthus niruri extract was also shown
to modulate nitric oxide release by
macrophages. These activities suggest that
stimulation of the immune system by the
extracts of P. niruri could be partly
responsible for the ethnomedicinal
applications in the management of
infectious diseases. ”
Phagocytosis is involved in the acquisition
of nutrients for some cells, and in the
immune system, it is a major mechanism
used to remove pathogens and cell debris.
Lysosomes are cellular organelles that
contain acid hydrolase enzymes to break up
waste materials and cellular debris.
Lysosomes are the cell ’s waste disposal
system and can break up anything.
Tumour necrosis factor (TNF, cachexin or
cachectin and formerly known as tumor
necrosis factor-alpha) is a cytokine involved
in systemic inflammation and is a member
of a group of cytokines that stimulate the
acute phase reaction. The primary role of
TNF is in the regulation of immune cells.
Nigerian researchers have also investigated
the effects of various concentrations of
aqueous extract of Phyllanthus niruri on
plasma glucose level and some hepato
specific markers in diabetic Wistar strain
rats.
The study was published in the Internet
Journal of Laboratory Medicine.
The lead researchers H. U. Nwanjo from the
Department of Medical Laboratory Science
Imo State University wrote: “The classes of
chemical components of the aqueous
extract of the plant were determined;
alkaloids, flavonoids and saponins were
found to be present. Acute toxicity test in
rats gave an LD50 of 516.2 mg/kg. The
name LD50 comes from toxicology, the
study of poisons. It is an abbreviation for
‘ Lethal Dose, 50 per cent’ or median lethal
dose. It gives the amount of the substance
required (usually per body weight) to kill 50
per cent of the test population.
“In this study we observed that the
administrated of aqueous extract of P.
niruri at the doses of 120 and 240 mg/kg
body weight to diabetic rats not only
caused a significant decrease in blood
glucose but also has a significant effect in
controlling the loss of body weight, which is
caused during diabetes.
“There were no significant difference in
alanine aminotransferase (ALT), aspartate
aminotransferase (AST), alkaline
phosphatase (ALP) activities as well as total,
conjugated and unconjugated billrubin
levels for the two experimental groups
respectively when compared with the
control group. The observations show that
the aqueous crude extract of Phyllanthus
niruri may have hypoglycaemic (low blood
glucose or low blood sugar) effect in
diabetic rats and that no evidence of
hepatotoxicity (implies chemical-driven liver
damage) of the extract was established.”
ALT is found in serum and in various bodily
tissues, but is most commonly associated
with the liver. It is commonly measured
clinically as a part of a diagnostic liver
function test, to determine liver health.
AST is similar to ALT in that it is another
enzyme associated with liver parenchymal
cells. The difference being ALT is found
predominately in the liver, with clinically
negligible quantities found in the kidneys,
heart, and skeletal muscle. AST is found in
the liver, heart, skeletal muscle, kidneys,
brain and red blood cells.
ALP is a hydrolase enzyme responsible for
removing phosphate groups from many
types of molecules, including nucleotides,
proteins, and alkaloids. The process of
removing the phosphate group is called
dephosphorylation.
Bilirubin (formerly referred to as
hematoidin) is the yellow breakdown
product of normal haeme catabolism.
Haeme is found in haemoglobin, a principal
component of red blood cells. Bilirubin is
excreted in bile and urine, and elevated
levels may indicate certain diseases. It is
responsible for the yellow color of bruises,
urine (dubious – discuss) and the yellow
discoloration in jaundice.
A lot of researchers who worked on
Phyllanthus niruri confirmed that it has
hypoglycaemic properties. It has also been
used for the treatment of other disease
conditions in various parts of the world. It
has been shown an excellent remedy of
jaundice and infective hepatitis. It is
effective in jaundice in children. The plant is
of medicinal importance for numerous
ailments like dysentery, diuretics, kidney
stones, influenza, antibacterial, anti-
hyperglycaemic and antiviral.
A lot of researchers have shown that
Phyllanthus niruri has protective action on
the different body organs especially the
liver and the kidney, and that no form of
toxicity has been associated with the usage
of this plant.
Another study published in African Journal
of Biotechnology by researchers at the
Department of Pharmacology and
Toxicology, Faculty of Pharmaceutical
Sciences, University of Nigeria, Nsukka,
concluded: “The results of this study
showed that aerial parts of P. niruri have
great potentials as anti-diabetic remedy due
to the ability of its extract to lower blood
glucose and lipid levels in diabetic rats and
suppress postprandial rise in blood glucose
levels.
These effects reduce the risk of
complications associated with diabetes. It
may additionally protect the pancreas from
further damage through antioxidant effect
and effective glycaemic control.
“Chronic use may not cause any deleterious
effect on haematological indices and body
weight. The whole extract of the aerial parts
may be more effective than the fractions
although this does not preclude the
isolation of hypoglycaemic constituents.
Studies on the effect of the plant extract on
peripheral glucose metabolism are
ongoing. ”
Researchers have also explored the
protective role of Phyllanthus niruri extract
on serum lipid profiles and oxidative stress
in hepatocytes of diabetic rats. The study
was published in African Journal of
Biotechnology by researchers at Imo State
University.
They wrote: “Diabetes mellitus has been
associated with lipid abnormalities and
oxidative stress. Some phytochemical
properties have been shown to possess
antioxidant activities, improving the effects
of oxidative stress on diabetes. This present
investigations confirmed that untreated
diabetic rats were associated with lipid
abnormalities as indicated by high level of
total and Low density Lipoprotein (LDL)-
cholesterol, that is bad cholesterol,
triacylglycerols (the main constituent of
vegetable oil and animal fats) and low levels
of High Density Lipoprotein (HDL)
cholesterol, that is good cholesterol, and
phospholipids (are a class of lipids and are a
major component of all cell membranes as
they can form lipid bilayers), compared to
non-diabetic rats (control).
“The aqueous extract of Phyllanthus niruri
significantly normalised the serum lipids
levels. The study also showed that
untreated diabetic rats were subjected to
oxidative stress as indicated by
significantly abnormal activities of their
scavenging enzymnes (superoxide
dismutase and catalase) and significantly
low levels of non-enzymic antioxidants
(Vitamin C, Vitamin E and reduced
glutathione) in liver and plasma when
compared with controls and in the extent of
lipid peroxidation (increased
malondialdehyde levels) in plasma and liver
cells. The aqueous extract of P. niruri
possessed antioxidant activities as shown
by increased activities of enzymic and non-
enzymic antioxidants and decrease in
malondialdehyde levels. ”
Catalase is a common enzyme found in
nearly all living organisms that are exposed
to oxygen, where it functions to catalyse
the decomposition of hydrogen peroxide to
water and oxygen.
Superoxide dismutase’s are a class of
enzymes that catalyze the dismutation of
superoxide into oxygen and hydrogen
peroxide. As such, they are an important
antioxidant defense in nearly all cells
exposed to oxygen.
Glutathione is an antioxidant, preventing
damage to important cellular components
caused by reactive oxygen species such as
free radicals and peroxides.
An antioxidant is a molecule capable of
inhibiting the oxidation of other molecules.
Oxidation is a chemical reaction that
transfers electrons from a substance to an
oxidizing agent. Oxidation reactions can
produce free radicals. In turn, these radicals
can start chain reactions that damage cells.
Antioxidants terminate these chain
reactions by removing free radical
intermediates, and inhibit other oxidation
reactions. They do this by being oxidised
themselves, so antioxidants are often
reducing agents such as thiols, ascorbic acid
or polyphenols.
It has been shown that although oxidation
reactions are crucial for life, they can also
be damaging; hence, plants and animals
maintain complex systems of multiple types
of antioxidants, such as glutathione, Vitamin
C, and Vitamin E as well as enzymes such as
catalase, superoxide dismutase and various
peroxidases. Low levels of antioxidants, or
inhibition of the antioxidant enzymes,
cause oxidative stress and may damage or
kill cells.
As oxidative stress might be an important
part of many human diseases, the use of
antioxidants in pharmacology is intensively
studied, particularly as treatments for stroke
and neurodegenerative diseases. However,
it is unknown whether oxidative stress is
the cause or the consequence of disease.
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.