PG2-2000 Activity Profile
PG2-2000 is a
further-refined and better-characterized complex polysaccharide.
It has similar activities as PG2 in that it promotes recovery of white
blood cells (WBCs) but PG2-2000 has augmented activities relative to PG2 in that
it promotes recovery of red blood cells (RBCs), and platelets (PLTs).
PG2-2000, tested in vitro and
in in vivo murine models of myelosuppression, acts as a multipotential
hematopoietic-stimulating agent, promotes recovery of WBCs, RBCs, and PLTs, and
alleviates leukopenia, anemia and thrombocytopenia associated with
myelosuppression. In addition, it accelerates multilineage hematopoietic reconstitution in syngeneic bone
marrow transplantation with both the donor and recipient treated with PG2-2000
to receive the best benefit. Most
importantly, PG2-2000 potentiates the response to G-CSF in models of
myelosuppression and autologous bone marrow transplantation.
In vitro assays demonstrated
that PG2-2000 triggered significant, dose-dependent release of hematopoietic
cytokines such as G-CSF, GM-CSF and IL-6 in Peripheral Blood Monocytes.
In a total body
irradiation-induced pancytopenia murine model, PG2-2000 was shown to accelerate
recovery of WBCs, RBCs and PLTs. It
also improved the RBC and PLT nadir value, and shortened the duration of
leukopenia, anemia and thrombocytopenia induced by radiation. Furthermore, in vivo results suggest that combination use of
PG2-2000 and G-CSF may provide an alternative therapy to reduce the pancytopenia
associated with myelosuppressive regimens for cancer patients in the clinic.
In addition to its
effect on myelosuppressed mice, PG2-2000 administered to normal mice increased
the number of bone marrow (BM) progenitors/stem cells (CD34+/-, c-Kit+, Sca-1+
and Lin-). These studies suggested
that treatment of the donor and recipient with PG2-2000 alone or in combination
with G-CSF may be an effective way to accelerate multilineage reconstitution
after myelosuppression and autologous bone marrow transplantation in the clinic.
Chemistry of PG2-2000
PG2-2000 is a
chemically-modified preparation of a specific arabinogalactan protein that is extracted and
purified, under FDA cGMP guidelines, from the Chinese medicinal plant we
Research at Pharmagenesis, Inc. has identified this arabinogalactan protein as being the
active component with respect to hematopoiesis.
elucidating the structure-activity relationships of PG2-2000 is a vital
aspect of our Large Molecule Research. Understanding
the structural basis of the biological activities of PG2-2000 will not only
facilitate regulatory approval, but may lead to the development of
pharmaceutical successors that are more efficacious, more economical to produce,
or more easily administered. A chemical derivative of PG2-2000 with oral bioavailability,
for instance, would be a worthy successor to PG2-2000.
Research and other candidates for hematopoiesis
The herbs that can
stimulate the hematopoietic systems are described in TCM to add tone to ‘Qi’
(energy), the Blood, the Yin and the Yang.
These herbs can strengthen or supplement an area of the body that is
insufficient or weakened. They are
used to benefit patients who have been ill with chronic or degenerative
In particular, cancer patients after chemotherapy have developed many symptoms like lethargy, lack of appetite, diarrhea; shortness of breath, shallow breathing, dyspnea on exertion, weak voice, pallid complexion, spontaneous sweating; pale tongue, fear of cold, cold extremities, sore or weak lower back; loss of voice, thirst, dry throat, etc. According to TCM theory, these symptoms are associated with Deficient Qi, Deficient Blood, Deficient Yang and Deficient Yin. It is the expertise of Pharmagenesis, Inc. to associate the TCM symptom description with the appropriate Western biological and medical parameters.