Evaluation of tear quantity and quality treated with gintonin eye drops in Labrador retrievers and English springer spaniels

Abstract

The aims of this study were to determine the relationship between tear osmolarity (TO), Schirmer tear test-1 (STT-
1) and tear film break-up time (TBUT) values in canines and to determine the impact of eye drops containing gintonin
- a ginseng-derived lysophosphatidic acid (LPA) receptor ligand - on these indices. Fourteen canines (four English
springer spaniels and ten Labrador retrievers) were randomized into two groups: the control group received only
placebo eye drops (carboxymethylcellulose), while the experimental group received carboxymethylcellulose eye drops
containing 5 µg of gintonin. Treatment was applied twice per day for a period of four weeks and STT-1, TBUT and TO
were evaluated both prior to and following the treatment period; the latter using I-PEN® VET (I-MED Animal Health,
QC, Canada). Pearson's correlation coefficients were calculated to investigate potential associations between baseline
TO, STT-1 and TBUT values. Within-group statistical significance of value changes induced by treatment was
determined using Student’s t-test. Positive correlations exist between TO and STT-1 values, as well as between TO and
TBUT values (P = 0.001 and P = 0.032, respectively). Gintonin treatment significantly increased only TBUT (21.0 ± 11.2
s versus 7.5 ± 2.8 s) and TO (317.1 ± 18.1 mOsm/L versus 302.2 ± 19.3 mOsm/L) values (P < 0.01 and P < 0.05,
respectively). The results suggest that gintonin improves canine tear film quality, as indicated by increased TBUT and
TO values.