Experimental and Clinical Applications of Chamaecyparis obtusa Extracts in Dry Eye Disease

Abstract

Purpose To investigate the effects of Chamaecyparis obtusa (CO) on human corneal epithelial (HCE) cells, a murine experimental dry eye (EDE) model, and the efficacy of antioxidant eye mask in dry eye disease (DED) patients. Methods 0.001%, 0.01%, and 0.1% CO extracts were used to treat HCE cells, cell viability, and production of antioxidative enzymes, and reactive oxygen species (ROS) were assessed. Afterwards, CO extracts or balanced salt solution (BSS) was applied in EDE. Clinical and experimental parameters were measured at 7 days after treatment. In addition, DED patients were randomly assigned to wear either an eye mask containing CO extracts or a placebo. Clinical parameters were evaluated. Results The viability of HCE cells and antioxidative enzyme expression significantly improved after treatment with 0.1% CO extracts. Mice treated with 0.1% CO extracts showed significant improvement in clinical parameters. During the trial, the clinical parameters significantly improved in the treatment group at 4 weeks after application. Conclusions 0.1% CO extracts could promote the expression of antioxidative proteins and ROS production. In addition, an eye mask containing CO extracts could improve DED clinical parameters. These suggest that CO extracts may be useful as an adjunctive option for the DED treatment.

Olive Pomace Phenolic Compounds and Extracts Can Inhibit Inflammatory- and Oxidative-Related Diseases of Human Ocular Surface Epithelium

“…Further, it compares extracts with different composition obtained from the same material, explaining their distinct activities. Regarding different plant materials, extracts from Camellia japonica [87], Chamaecyparis obtuse [88], Aloe vera [44], Euphrasia officinalis [89], Lamium album [90], Polygonum cuspidatum [46], and Maple leaves [45] have also been found to reduce inflammatory biomarkers in human corneal cells. Hence, the potential of naturally derived polyphenols and polyphenols-rich extract is becoming an emerging issue in the field.…”

Effects of Eurya japonica extracts on human corneal epithelial cells and experimental dry eye

“…The close relationship between lipid peroxidation-related membrane injury, protein oxidation, ROS production and inflammation was confirmed in patients and animal models of DE (7)(8)(9). Previous studies have demonstrated that topically applied medicinal plant extracts or tropical tree leaf extracts are effective for stressed human corneal epithelial (HCE) cells and murine DE by exhibiting anti-oxidative and anti-inflammatory properties (10)(11)(12). Furthermore, anti-oxidative glasses containing extracts of medicinal plants were also indicated to be effective in improving symptoms of DE, both reducing dryness and redness and increasing tear break up time (TBUT) and Schirmer's test results (13).…”

“…However, these agents have variable therapeutic responses and are unable to achieve complete resolution of inflammatory DE (11,31). Topical or local application of anti-oxidative agents may be a novel treatment approach for DE (10)(11)(12). Among agents that have anti-inflammatory and anti-oxidant effects for the treatment of DE, the efficacy of different concentrations of EJ extracts was evaluated via topical application.…”

“…Previous studies have demonstrated that topical administration of anti-oxidants could decrease inflammation on the ocular surface of animal EDE (10)(11)(12)(13). It has also been demonstrated that topical application of anti-inflammatory medicines exerted beneficial effects on tear film stability and ocular surface integrity (44,45).…”

“…Levels of intracellular ROS production were measured using a CM-H2DCFDA kit according to the manufacturer's protocol, as previously described ( 12 ). In summary, the conjunctivas of the mice (5 eyes/group) were surgically harvested, dipped in PBS, torn apart using scissors and incubated at 37°C for 1 h in the presence of 0.5 mg/ml collagenase type D (Roche Applied Science).…”