Polyacetylenes function as anti-angiogenic agents.

Area of Science:

• Pharmacology
• Natural Products Chemistry
• Molecular Biology

Background:

• Bidens pilosa Linn. is a widely used medicinal herb and nutraceutical.
• Its extracts are traditionally employed for anti-inflammatory and antitumor properties.
• Angiogenesis plays a critical role in tumor growth and metastasis.

Purpose of the Study:

• To investigate the antiangiogenic potential of Bidens pilosa extracts and isolated polyacetylenes.
• To identify specific compounds responsible for these effects.
• To elucidate the molecular mechanisms underlying the anti-angiogenic activity.

Main Methods:

• Bioactivity-guided fractionation of Bidens pilosa extracts.
• In vitro assays including anti-cell proliferation, anti-tube formation, and cell migration.
• High-performance liquid chromatography (HPLC) and spectral analyses for compound identification.
• Western blot analysis to assess protein expression.

Main Results:

• An ethyl acetate fraction of Bidens pilosa demonstrated significant anti-angiogenic activity against human umbilical vein endothelium cells (HUVEC).
• Two polyacetylenes, 1,2-dihydroxytrideca-5,7,9,11-tetrayne (1) and 1,3-dihydroxy-6(E)-tetradecene-8,10,12-triyne (2), were isolated.
• Both compounds potently inhibited HUVEC proliferation and tube formation, with compound 2 showing higher efficacy in proliferation inhibition and compound 1 in tube formation inhibition.
• Compounds 1 and 2 upregulated cyclin-dependent kinase inhibitors p27(Kip1) and p21(Cip1) in HUVEC.

Conclusions:

• This study provides the first evidence that polyacetylenes from Bidens pilosa exhibit significant anti-angiogenic properties.
• The identified polyacetylenes effectively inhibit endothelial cell proliferation and angiogenesis.
• These compounds modulate the expression of key cell cycle regulators, suggesting a mechanism for their anti-angiogenic action.