Green Tea Catechins Attenuate Human Primary Pterygium Cell Survival and Migration Via Modulation of ERK p42/p44 and p38 Pathways

Abstract

Pterygium belongs to an ocular surface disease with triangular-shaped hyperplastic growth, characterized by conjunctivalization, inflammation, and connective tissue remodeling. We previously demonstrated neoplastic-like properties of pterygium cells. Green tea catechin, (−)-epigallocatechin gallate (EGCG), has been shown to possess antitumorigenic properties; herein, we aimed to determine the effects of green tea catechins on human primary pterygium cell survival and migration and compared to that on patients' conjunctival cells. Both human primary pterygium and conjunctival cells expressed EGCG receptor, the 67 kDa laminin receptor. Seven-day treatment of green tea extract (Theaphenon E; 16.25 μg/mL) and EGCG (25 μM) attenuated pterygium cell proliferation by 16.78% (p < 0.001) and 24.09% (p < 0.001) respectively, without significantly influencing conjunctival cells. Moreover, green tea extract (16.25 μg/mL) and EGCG (25 μM) treatments also hindered pterygium cell migration by 35.22% (p < 0.001) and 25.20% (p = 0.019), respectively, but not conjunctival cells. Yet, green tea extract and EGCG treatments did not significantly induce pterygium cell apoptosis. Furthermore, green tea extract and EGCG treatments significantly increased the phosphorylation of p38 protein but reduced the phosphorylation of p42/p44 protein in pterygium cells. In summary, this study revealed that green tea extract and EGCG attenuated human primary pterygium cell survival and migration in vitro without damaging conjunctival cells, suggesting a novel potential therapeutic approach for primary pterygium treatment.

Green Tea Catechins as Therapeutic Antioxidants for Glaucoma Treatment

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Hydroxychloroquine treatment on SARS-CoV-2 receptor ACE2, TMPRSS2 and NRP1 expression in human primary pterygium and conjunctival cells

“…Written informed consent was obtained from all study subjects before inclusion into the study. Human primary pterygium ( n = 3) and conjunctival ( n = 3) cell lines have been established and characterized as previously described ( Yang et al, 2019a , 2021 ). Briefly, full-length primary pterygium tissues from the affected eyes as well as conjunctiva tissues from contra-lateral unaffected eyes were freshly collected from pterygium excision surgery with conjunctival autograft.…”

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