Faculty of Science - Mahidol University

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The water decoction of heartwood and stem bark of Ventilago
harmandiana Pierre (Family Rhammnaceae) are used in Thai
traditional medicine for the treatment of diabetes as well as wound
and chronic inflammation. Methanolic extracts from the heart wood,
stem bark, stem wood and pure compounds of the herb exerted strong
inhibitory effects on the acute phase of inflammation as seen in
ethyl phenylpropiolate (EPP)-induced ear edema as well as in
carragenin-induced paw edema in rats. Activated macrophages
participate actively in the inflammatory response by producing large
amounts of pro-inflammatory cytokines such as TNF-α,
chemoattractant cytokines such as IL-8 and pro-inflammatory
products of arachidonic acid metabolism as well as nitric oxide.
This study examined whether a quinone and two anthraquinone
compounds from Ventilago harmandiana modulate the production
of PGE 2 , tumour necrosis factor-á (TNF-á) and nitric oxide (NO) by
LPS-activated human macrophages. The expression of the mRNA
of COX-2 and TNF-á was also investgated. All three compounds
from Ventilago harmandiana were shown to significantly inhibit
the production of TNF-á and PGE 2 in a concentration-dependent
manner without notable cytotoxic effects on these cells. The
expression of both TNF-á and COX-2 mRNA was also significantly
inhibited by these compounds. However, neither the production of
NO nor iNOS mRNA expression could be detected from LPS-human
activated macrophages. These results indicated that the inhibitory
effects of a quinone and the two anthraquinone compounds from
Ventilago harmandiana Pierre on the production, by activated human
macrophages, of PGE 2 and TNF-á which is regulated at the
transcriptional level might be attributed, in part, to their antiinflammatory
activities.
INHIBITORY EFFECTS OF NEUTROPHIL FUNC-
TION AND T-LYMPHOCYTES PROLIFERTION
BY PUERARIA MIRIFICA EXTRACTS (NO. 856)
Payong Wanikiat 1 , Yupin Sanvarinda 1 , Taworn Jaipetch 2 ,
Vichai Reutrakul 2
1 Department of Pharmacology, 2 Department of Chemistry,
Faculty of Science, Mahidol University, Bangkok 10400,
Thailand.
Key words : Pueraria mirifica; Inflammation; Anti-inflammation;
Neutrophil functions; Chemotaxis; Superoxide anion generation;
MPO production; Elastase release
Pueraria mirifica (P. mirifica) Airy Shaw (Legumunosae),
a phytoestrogen – rich plant with a local name of white Kwao Krrua,
has long been used in Thailand as a rejuvenating folk medicine. It
has also been used by menopausal women for the hormonal
replacement purpose. The chemical compounds found in the plant
including Isoflavones and glycosides e.g. daidzein, genistein,
kwakurin; Chromenes e.g. miroestrol, deoxymiroestrol,
isomiroestrol, Comestans e.g. coumestrol and Pterocarpans e.g.
puemiricarpene etc. It is believed that the content of phytoestrogen
in the plants are of therapeutic benefit. Some active ingredients of
P. mirifica such as miroestrol exhibit estrogenic like activity.
Estrogen plays a protective role on cardiovascular system and has
been known to exert anti-inflammatory effects both in vivo and in
vitro by inhibiting the expression and production of various proinflammatory
mediators. In this study, methanol and ethylacetate
extracts of Pueraria mirifica were investigated for their antiinflammatory
activities based on neutrophil functions, including
chemotaxis, superoxide anion generation (SAG), myeloperoxidase
(MPO) production, and elastase release, and on T-lymphocyte
proliferation. Both crude extracts were primarily investigated for
their cytotoxic effects on both neutrophils and lymphocytes using
MTT assay. Neutrophil viability was not affected by these
compounds (1-100 μg/ml) either at 4 hours incubation period, except
at a concentration of 1000 μg/ml (IC 50 >1000). After incubation of
human neutrophils with various concentrations of both methanol
and ethylacetate extracts of Pueraria mirifica, neutrophil
chemotaxis, SAG, MPO production, and elastase release induced
by N-formyl-methionyl-leucyl-phenylalanine (fMLP) were strongly
inhibited in a concentration-dependent manner. Both crude extracts
also inhibited T-lymphocyte proliferation as quantified by [H 3 ]
thymidine incorporation.
These results suggested that the inhibitory effects of the
Pueraria mirifica extracts on neutrophil functions and T-lymphocyte
proliferation might be attributed, in part, to their anti-inflammatory
activities.
CONCERTED MECHANISM OF SWE1/WEE1
REGULATION BY MULTIPLE KINASES IN
BUDDING YEAST. (NO. 857)
Satoshi Asano 1 , Jung-Eun Park 1 , Krisada Sakchaisri 1, 2 , Li-
Rong Yu 3 , Sukgil Song 4 , Porntip Supavilai 2 , Timothy D Veenstra 3
and Kyung S Lee 1
1 Laboratory of Metabolism, Center for Cancer Research,
National Cancer Institute, NIH, Bethesda, MD, USA.
2 Department of Pharmacology, Faculty of Science, Mahidol
University, Bangkok, Thailand. 3 Laboratory of Proteomics and
Analytical Technologies, NCI-Frederick, Frederick, MD, USA.
4 College of Pharmacy, Chungbuk National University, South
Korea.
Key words : Cdc5, Cdc28, G2/M transition, Swe1
In eukaryotes, entry into mitosis is induced by cyclin Bbound
Cdk1, which is held in check by the protein kinase, Wee1. In
budding yeast, Swe1 (Wee1 ortholog) is targeted to the bud neck
through Hsl1 (Nim1-related kinase) and its adaptor Hsl7, and is
hyperphosphorylated prior to ubiquitin-mediated degradation. Here,
we show that Hsl1 and Hsl7 are required for proper localization of
Cdc5 (Polo-like kinase homolog) to the bud neck and Cdc5dependent
Swe1 phosphorylation. Mitotic cyclin (Clb2)-bound
Cdc28 (Cdk1 homolog) directly phosphorylated Swe1 and this
modification served as a priming step to promote subsequent Cdc5dependent
Swe1 hyperphosphorylation and degradation. Clb2-Cdc28
also facilitated Cdc5 localization to the bud neck through the
enhanced interaction between the Clb2-Cdc28-phosphorylated Swe1
and the polo-box domain of Cdc5. We propose that the concerted
action of Cdc28/Cdk1 and Cdc5/Polo on their common substrates
is an evolutionarily conserved mechanism that is crucial for
effectively triggering mitotic entry and other critical mitotic events.
(EMBO J. 24, (2005) 2194-2204.)
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Faculty of Science