TY - JOUR
T1 - Tryptophan-Derived 3-Hydroxyanthranilic Acid Contributes to Angiotensin II-Induced Abdominal Aortic Aneurysm Formation in Mice in Vivo
AU - Wang, Qiongxin
AU - Ding, Ye
AU - Song, Ping
AU - Zhu, Huaiping
AU - Okon, Imoh
AU - Ding, Yang Nan
AU - Chen, Hou Zao
AU - Liu, De Pei
AU - Zou, Ming Hui
N1 - Funding Information:
This study was supported by National Institutes of Health grants (HL079584, HL080499, HL089920, HL110488, HL128014, HL132500, HL137371, HL140954, AG047776, and CA213022). This work was supported, in part, by the Georgia Research Alliance. Dr Zou is a Georgia Research Alliance Eminent Scholar in Molecular Medicine. Dr Chen is supported by the Youth Top-Notch Talent Support Program and the Youth Yangtze River Scholar Program in China.
PY - 2017/12/5
Y1 - 2017/12/5
N2 - Background: Abnormal amino acid metabolism is associated with vascular disease. However, the causative link between dysregulated tryptophan metabolism and abdominal aortic aneurysm (AAA) is unknown. Methods: Indoleamine 2,3-dioxygenase (IDO) is the first and rate-limiting enzyme in the kynurenine pathway of tryptophan metabolism. Mice with deficiencies in both apolipoprotein e (Apoe) and IDO (Apoe-/-/IDO-/-) were generated by cross-breeding IDO-/- mice with Apoe-/- mice. Results: The acute infusion of angiotensin II markedly increased the incidence of AAA in Apoe-/- mice, but not in Apoe-/-/IDO-/- mice, which presented decreased elastic lamina degradation and aortic expansion. These features were not altered by the reconstitution of bone marrow cells from IDO+/+ mice. Moreover, angiotensin II infusion instigated interferon-γ, which induced the expression of IDO and kynureninase and increased 3-hydroxyanthranilic acid (3-HAA) levels in the plasma and aortas of Apoe-/- mice, but not in IDO-/- mice. Both IDO and kynureninase controlled the production of 3-HAA in vascular smooth muscle cells. 3-HAA upregulated matrix metallopeptidase 2 via transcription factor nuclear factor-κB. Furthermore, kynureninase knockdown in mice restrained 3-HAA, matrix metallopeptidase 2, and resultant AAA formation by angiotensin II infusion. Intraperitoneal injections of 3-HAA into Apoe-/- and Apoe-/-/IDO-/- mice for 6 weeks increased the expression and activity of matrix metallopeptidase 2 in aortas without affecting metabolic parameters. Finally, human AAA samples had stronger staining with the antibodies against 3-HAA, IDO, and kynureninase than those in adjacent nonaneurysmal aortic sections of human AAA samples. Conclusions: These data define a previously undescribed causative role for 3-HAA, which is a product of tryptophan metabolism, in AAA formation. Furthermore, these findings suggest that 3-HAA reduction may be a new target for treating cardiovascular diseases.
AB - Background: Abnormal amino acid metabolism is associated with vascular disease. However, the causative link between dysregulated tryptophan metabolism and abdominal aortic aneurysm (AAA) is unknown. Methods: Indoleamine 2,3-dioxygenase (IDO) is the first and rate-limiting enzyme in the kynurenine pathway of tryptophan metabolism. Mice with deficiencies in both apolipoprotein e (Apoe) and IDO (Apoe-/-/IDO-/-) were generated by cross-breeding IDO-/- mice with Apoe-/- mice. Results: The acute infusion of angiotensin II markedly increased the incidence of AAA in Apoe-/- mice, but not in Apoe-/-/IDO-/- mice, which presented decreased elastic lamina degradation and aortic expansion. These features were not altered by the reconstitution of bone marrow cells from IDO+/+ mice. Moreover, angiotensin II infusion instigated interferon-γ, which induced the expression of IDO and kynureninase and increased 3-hydroxyanthranilic acid (3-HAA) levels in the plasma and aortas of Apoe-/- mice, but not in IDO-/- mice. Both IDO and kynureninase controlled the production of 3-HAA in vascular smooth muscle cells. 3-HAA upregulated matrix metallopeptidase 2 via transcription factor nuclear factor-κB. Furthermore, kynureninase knockdown in mice restrained 3-HAA, matrix metallopeptidase 2, and resultant AAA formation by angiotensin II infusion. Intraperitoneal injections of 3-HAA into Apoe-/- and Apoe-/-/IDO-/- mice for 6 weeks increased the expression and activity of matrix metallopeptidase 2 in aortas without affecting metabolic parameters. Finally, human AAA samples had stronger staining with the antibodies against 3-HAA, IDO, and kynureninase than those in adjacent nonaneurysmal aortic sections of human AAA samples. Conclusions: These data define a previously undescribed causative role for 3-HAA, which is a product of tryptophan metabolism, in AAA formation. Furthermore, these findings suggest that 3-HAA reduction may be a new target for treating cardiovascular diseases.
KW - 3-hydroxyanthranilic acid
KW - angiotensin II
KW - aortic aneurysm, abdominal
KW - indoleamine-pyrrole 2,3-dioxygenase
KW - matrix metallopeptidases
KW - tryptophan
UR - http://www.scopus.com/inward/record.url?scp=85037085504&partnerID=8YFLogxK
U2 - 10.1161/CIRCULATIONAHA.117.030972
DO - 10.1161/CIRCULATIONAHA.117.030972
M3 - Article
C2 - 28978552
AN - SCOPUS:85037085504
SN - 0009-7322
VL - 136
SP - 2271
EP - 2283
JO - Circulation
JF - Circulation
IS - 23
ER -