Abstract
Purpose: :
We have demonstrated that repeated jogging board (JB) treatment in desiccating condition, induced abnormal tear dynamics and superficial punctate keratopathy (SPK) similar to that in humans (IOVS, 2005). The purpose of this study was to investigate the effect of D–ß–Hydroxybutyrate (HBA) on chronic SPK. We compared the potency of HBA with serum, of which the efficacy in clinical application has been well proven.
Methods: :
A series of treatments were performed under continuous exposure to low–humidity airflow (25 ± 5%, 2–4 m/s). Female SD rats aged 7 weeks were used for this study. Rats were placed on a JB made of a plastic pipe for 7.5 h/d, and, for 16.5 hours, they were placed in individual cages without JB treatment.Ten days after rat eyes were applied phosphate–buffered saline (PBS) every 2 hours during JB treatment, eyes that showed SPK were examined. Eyes were randomly selected for 0.04, 0.2, 1% HBA eye drops, 20% rat serum or PBS as a control (n=13–14). Five microlitters of eye drops were then given every 2 hours for 8 hours during JB treatment. After the onset of 14 and 21 days application, SPK was recorded according to the protocol described by Shimmura and associates (Shimmura et. al. Br J Ophthalmol 1995).
Results: :
For the PBS and 0.04% HBA group, the SPK score were not changed compared to the initial values during experiment. Topically applied 0.2, 1% HBA and 20% rat serum, dramatically recovered the SPK score after 14 and 21 days of treatment and significant decreases were observed compared to the initial (P < 0.01) and PBS treatment values (P < 0.05) . The effect of 0.2, 1% HBA was as potent as 20% serum.
Conclusions: :
This study suggests the potential usefulness of HBA in the clinical treatment of ocular surface epithelial disorders in patients with chronic symptom of dry eye.
Keywords: cornea: tears/tear film/dry eye • cornea: epithelium • cornea: basic science