Prevention of endotoxin-induced uveitis in rats by plant sterol guggulsterone.
OBJECTIVE
To investigate the anti-inflammatory effects of guggulsterone, an antioxidant and antitumor agent, in endotoxin-induced uveitis (EIU) in rats and to elucidate the underlying molecular mechanism or mechanisms related to ocular inflammation.


METHODS
EIU was induced by subcutaneous injection of lipopolysaccharide (LPS; 150 μg) into Lewis rats treated with guggulsterone (30 mg/kg body weight, intraperitoneally) or its carrier. After 24 hours the rats were killed, eyes were enucleated, and aqueous humor (AqH) was collected. Numbers of infiltrating cells and levels of matrix metalloproteinase-2 (MMP-2), nitric oxide (NO), and prostaglandin E(2) (PGE(2)) were determined in AqH by specific ELISAs. An antibody array was used to measure the expression of various inflammatory cytokines in AqH. The expression of MMP-2, iNOS, Cox-2, phospho-IκB, and phospho-NF-κB was determined immunohistochemically. Human primary nonpigment ciliary epithelial cells (HNPECs) were used to determine the in vitro efficacy of guggulsterone on the LPS-induced inflammatory response.


RESULTS
Compared with control, the EIU rat eye AqH had a significantly higher number of infiltrating cells, total protein, and inflammatory markers, such as MMP-2, NO, and PGE(2), and the treatment of guggulsterone prevented EIU-induced increases. Guggulsterone also prevented the expression of MMP-2, iNOS, and Cox-2 proteins and of IκB and NF-κB in various eye tissues. Moreover, in cultured HNPECs, guggulsterone inhibited LPS-induced expression of inflammatory proteins.


CONCLUSIONS
These results for the first time demonstrate that the plant sterol guggulsterone suppresses ocular inflammation in EIU, suggesting that the supplementation of guggulsterone could be a novel approach for the treatment of ocular inflammation.
Kalariya
Nilesh M
NM
Department of Ophthalmology and Visual Sciences, University of Texas Medical Branch, Galveston, Texas, USA.
Shoeb
Mohammad
M
Reddy
Aramati B M
AB
Zhang
Min
M
van Kuijk
Frederik J G M
FJ
Ramana
Kota V
KV
D000818:Animals; D000970:Antineoplastic Agents / Q000627:therapeutic use*; D000975:Antioxidants / Q000627:therapeutic use*; D001082:Aqueous Humor / Q000166:cytology / Q000378:metabolism; D015153:Blotting, Western; D002478:Cells, Cultured; D002924:Ciliary Body / Q000187:drug effects; D029744:Commiphora; D016207:Cytokines / Q000378:metabolism; D015232:Dinoprostone / Q000378:metabolism; D004195:Disease Models, Animal; D004797:Enzyme-Linked Immunosorbent Assay; D004926:Escherichia coli; D006801:Humans; D020672:I-kappa B Proteins / Q000378:metabolism; D007274:Injections, Intraperitoneal; D008070:Lipopolysaccharides; D008297:Male; D020778:Matrix Metalloproteinase 2 / Q000378:metabolism; D016328:NF-kappa B / Q000378:metabolism; D009569:Nitric Oxide / Q000378:metabolism; D052247:Nitric Oxide Synthase Type II / Q000378:metabolism; D011282:Pregnenediones / Q000627:therapeutic use*; D051381:Rats; D011917:Rats, Inbred Lew; D014605:Uveitis / Q000139:chemically induced / Q000378:metabolism / Q000517:prevention & control*
D000970:Antineoplastic Agents; D000975:Antioxidants; D016207:Cytokines; D020672:I-kappa B Proteins; D008070:Lipopolysaccharides; D016328:NF-kappa B; D011282:Pregnenediones; D009569:Nitric Oxide; C023617:pregna-4,17-diene-3,16-dione; D052247:Nitric Oxide Synthase Type II; C496318:Nos2 protein, rat; D020778:Matrix Metalloproteinase 2; D015232:Dinoprostone