Anti-proliferative effect of olmesartan on Tenon's capsule fibroblasts.
OBJECTIVE
To evaluate the inhibitive effect of olmesartan to fibroblast proliferation and the anti-scarring effect in Tenon's capsule, both in vitro and in vivo.


METHODS
Human primary Tenon's capsule fibroblasts were cultured in vitro, treated with up titrating concentrations of olmesartan. The rate of inhibition was tested with methyl thiazol tetrazolium (MTT) method. Real-time PCR was performed to analyze changes in mRNA expressions of the fibrosis-related factors: matrix metalloproteinase-2 (MMP-2), tissue inhibitor of metalloproteinase (TIMP-1,2) and proliferating cell nuclear antigen (PCNA). Thirty rabbits were divided into 5 groups (3, 7, 14, 21, and 28d). A rabbit conjunctiva flap model was created in each eye. Olmesartan solution was injected subconjunctivally and then evaluated its anti-proliferation and anti-fibrosis effects through the histological morphology and immunohistochemistry of MMP-2 and PCNA in each group. Only the 7d group was treated with Masson's trichrome to compare the neovascularization in the subconjunctiva area.


RESULTS
In vitro, cultured Tenon's capsule human fibroblasts showed a dose dependent inhibition by olmesartan in MTT. Olmesartan reduced mRNA expressions of MMP-2 and PCNA but increased mRNA expressions of TIMP-1 and TIMP-2. In vivo, the rabbit eyes treated with olmesartan at 3(rd), 7(th), 14(th) and 21(st) days demonstrated a significant reduced expressions of MMP-2 and PCNA compared with control eye, no significant difference observed in 28(th) day group. The cellular proliferation and neovascularization was suppressed by olmesartan in Masson's trichrome observation.


CONCLUSIONS
By inhibiting fibroblasts in vitro and in vivo, olmesartan prevents the proliferation and activity of fibroblasts in scar tissue formation, which might benefit glaucoma filtering surgery.
Department of Ophthalmology, the Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an 710004, Shaanxi Province, China.
Xuan
X
Wang
Department of Ophthalmology, the Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an 710004, Shaanxi Province, China.
Ya-Zhi
YZ
Fan
Department of Ophthalmology, the Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an 710004, Shaanxi Province, China.
Liang
L
Yao
Department of Ophthalmology, the Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an 710004, Shaanxi Province, China.
Jian-Ming
JM
Wang
anti-proliferative; matrix metalloproteinase-2; olmesartan; proliferating cell nuclear antigen; trabeculectomy