Butyrate-induced proapoptotic and antiangiogenic pathways in EAT cells require activation of CAD and downregulation of VEGF.

Abstract

Butyrate, a short-chain fatty acid produced in the colon, induces cell cycle arrest, differentiation, and apoptosis in transformed cell lines. In this report, we study the effects of butyrate (BuA) on the growth of Ehrlich ascites tumor (EAT) cells in vivo. BuA, when injected intraperitoneally (i.p) into mice, inhibited proliferation of EAT cells. Further, induction of apoptosis in EAT cells was monitored by nuclear condensation, annexin-V staining, DNA fragmentation, and translocation of caspase-activated DNase into nucleus upon BuA-treatment. Ac-DEVD-CHO, a caspase-3 inhibitor, completely inhibited BuA-induced apoptosis, indicating that activation of caspase-3 mediates the apoptotic pathway in EAT cells. The proapoptotic effect of BuA also reflects on the antiangiogenic pathway in EAT cells. The antiangiogenic effect of BuA in vivo was demonstrated by the downregulation of the secretion of VEGF in EAT cells. CD31 immunohistochemical staining of peritoneum sections clearly indicated a potential angioinhibitory effect of BuA in EAT cells. These results suggest that BuA, besides regulating other fundamental cellular processes, is able to modulate the expression/secretion of the key angiogenic growth factor VEGF in EAT cells.

• Authors: Madesh Belakavadi, B T Prabhakar, Bharathi P Salimath
• Journal: Biochemical and biophysical research communications (Biochem Biophys Res Commun) Vol. 335 Issue 4 Pg. 993-1001 (Oct 07 2005) ISSN: 0006-291X [Print] United States
• PMID: 16105646 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Vascular Endothelial Growth Factor A
• vascular endothelial growth factor A, mouse
• Butyric Acid
• Deoxyribonucleases
• caspase-activated deoxyribonuclease

Topics

• Animals
• Apoptosis (drug effects)
• Butyric Acid (administration & dosage)
• Carcinoma, Ehrlich Tumor (blood supply, drug therapy, metabolism, pathology)
• Cell Line, Tumor
• Cell Proliferation (drug effects)
• Deoxyribonucleases (drug effects, metabolism)
• Down-Regulation (drug effects)
• Enzyme Activation (drug effects)
• Gene Expression Regulation, Neoplastic (drug effects)
• Mice
• Neovascularization, Pathologic (metabolism, prevention & control)
• Signal Transduction (drug effects)
• Vascular Endothelial Growth Factor A (metabolism)