Role of VEGF in small bowel adaptation after resection: the adaptive response is angiogenesis dependent.
Previous work in our group has demonstrated that mouse salivary gland has the highest concentration of salivary-derived VEGF protein compared with other organs and is essential for normal palatal mucosal wound healing. We hypothesize that salivary VEGF plays an important role in maintaining the integrity of the gastrointestinal mucosa following small bowel resection (SBR). Thirty-five 8- to 10-wk-old C57BL/6 female mice were divided into seven treatment groups: 1) sham (transaction and anastomosis, n = 5); 2) SBR (n = 8); 3) sialoadenectomy and small bowel resection (SAL+SBR, n = 8); 4) sialoadenectomy and small bowel resection with EGF supplementation (SAL+SBR+EGF, n = 9); 5) sialoadenectomy and small bowel resection with VEGF supplementation (SAL+SBR+VEGF, n = 9); 6) sialoadenectomy and small bowel resection supplemented with EGF and VEGF (SAL+ SBR+VEGF+EGF, n = 6); 7) selective inhibition of VEGF in the submandibular gland by Ad-VEGF-Trap following small bowel resection (Ad-VEGF-Trap+SBR, n = 7). Adaptation was after 3 days by ileal villus height and crypt depth. The microvascular response was evaluated by CD31 immunostaining and for villus-vessel area ratio by FITC-labeled von Willebrand factor immunostaining. The adaptive response after SBR was significantly attenuated in the SAL group in terms of villus height (250.4 +/- 8.816 vs. 310 +/- 19.35, P = 0.01) and crypt depth (100.021 +/- 4.025 vs. 120.541 +/- 2.82, P = 0.01). This response was partially corrected by orogastric VEGF or EGF alone. The adaptive response was completely restored when both were administered together, suggesting that salivary VEGF and EGF both contribute to intestinal adaptation. VEGF increases the vascular density (6.4 +/- 0.29 vs. 6.1 +/- 0.29 vs. 5.96 +/- 0.20) and villus-vessel area ratio (0.713 +/- 0.01 vs. 0.73 +/- 0.01) in the adapting bowel. Supplementation of both EGF and VEGF fully rescues adaptation, suggesting that the adaptive response may be dependent on VEGF-driven angiogenesis. These results support a previously unrecognized role for VEGF in the small bowel adaptive response.
Parvadia
Jignesh K
JK
Center for Molecular and Fetal Therapy, Division of Pediatric General, Thoracic, and Fetal Surgery, Cincinnati Children's Hospital Medical Center, 3333 Burnet Avenue, Cincinnati, OH 45229-3039, USA.
Keswani
Sundeep G
SG
Vaikunth
Sachin
S
Maldonado
Arturo R
AR
Marwan
A
A
Stehr
Wolfgang
W
Erwin
Christopher
C
Uzvolgyi
Eva
E
Warner
Brad W
BW
Yamano
Seichii
S
Taichman
Norton
N
Crombleholme
Timothy M
TM
D000222:Adaptation, Physiological; D000256:Adenoviridae / Q000235:genetics; D000818:Animals; D049109:Cell Proliferation; D004815:Epidermal Growth Factor / Q000378:metabolism; D005260:Female; D018014:Gene Transfer Techniques; D005822:Genetic Vectors; D007082:Ileum / Q000098:blood supply / Q000378:metabolism* / Q000503:physiopathology / Q000601:surgery; D007413:Intestinal Mucosa / Q000378:metabolism* / Q000473:pathology / Q000503:physiopathology / Q000601:surgery; D051379:Mice; D008810:Mice, Inbred C57BL; D008871:Microvilli / Q000378:metabolism / Q000473:pathology; D023421:Models, Animal; D018919:Neovascularization, Physiologic; D040262:Receptors, Vascular Endothelial Growth Factor / Q000235:genetics / Q000378:metabolism; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D012469:Salivary Glands / Q000378:metabolism* / Q000601:surgery; D013997:Time Factors; D042461:Vascular Endothelial Growth Factor A / Q000097:blood / Q000378:metabolism*
D011993:Recombinant Fusion Proteins; C475927:VEGF-Trap fusion protein, recombinant; D042461:Vascular Endothelial Growth Factor A; C467480:vascular endothelial growth factor A, mouse; D004815:Epidermal Growth Factor; D040262:Receptors, Vascular Endothelial Growth Factor