Abstract
Purpose :
Meibomian gland dysfunction (MGD) is known to be a major cause of dry eye disease, with various ocular surface disorders. Currently, appropriate eye drops are prescribed to deal with MGD, as well with thermal and mechanical means such as warm compresses or lid scrubs. Minocycline is one of the tetracycline antibiotics, routinely being prescribed to MGD patients for oral administration. It is proven to be effective in dealing with MGD symptoms but has potential risks such as photosensitivity, gastrointestinal disturbances (emesis, diarrhea, and dyspepsia), and genitourinary symptoms, etc. If possible, the use of minocycline ointment may reduce some of the known risks with the same effect. Since there is no study yet regarding the use of minocycline ointment on MGD, the authors aimed to investigate the effect of minocycline ointment in the MGD rat model.
Methods :
Cell viability test was conducted using human corneal epithelial cells and the appropriate concentration of minocycline without toxicity was confirmed. Then the proven concentration was compared with the currently available minocycline ointment for in vivo experiment. MGD rat model was established using CFA injection on the nasal and lateral eyelid margin of six-week-old male SD rats. After MGD induction for a week, the rats were treated with minocycline ointment twice a day for three weeks. A total of six experimental groups were used, including control, control with minocycline ointment, MGD, MGD with hyaluronic acid, MGD with oxytetracycline, MGD with cyclosporine, and MGD with minocycline ointment. Symptom scores (tear break-up time, corneal fluorescent staining score, telangiectasia score, and eyelid swelling score) were assessed every week for three weeks, then the rats were sacrificed for immunohistochemistry.
Results :
The use of minocycline ointment in MGD rat model alleviated the symptoms showing decreased corneal fluorescent, lid swelling, and telangiectasia scores, as well with increased tear break-up time. Also, the level of inflammatory cytokines, IL-1b, IL-6, and TNF-a, were lowered after minocycline ointment treatment in corneal, conjunctiva, and meibomian gland tissues.
Conclusions :
In conclusion, this study confirmed the positive effect of minocycline ointment in the MGD rat model, having lower symptom scores, higher tear break-up time, and showing the reduced level of inflammation in cornea, conjunctiva, and meibomian gland tissues.
This abstract was presented at the 2022 ARVO Annual Meeting, held in Denver, CO, May 1-4, 2022, and virtually.