Abstract
Purpose :
Vitamin D (vitD) has been associated not only with bone metabolism but also with inflammatory and degenerative processes. The vitamin D receptor (VDR) is a transcription factor that, linked to vitD, regulates the expression of numerous genes. Dry eye disease (DED) is a frequent multifactorial disease that leads to a serious deterioration in the quality of life. Studies have shown an association of DED with vitD deficiency, however, there are no studies that have analyzed the metabolism of this pathway at the cellular level. It is our objective to study the expression of the VDR in patients with DED.
Methods :
Nineteen patients with DED without previous treatment and 10 age matched healthy subjects were studied. The Ocular Surface Disease Index (OSDI) and a cytobrush ocular surface cytology were performed on all patients. Squamous metaplasia was morphologically evaluated by liquid phase cytology with PAP-PAS staining using the Nelson’s score (scale 0 to 3, higher score to higher metaplastic change). The immunohistochemical expression of VDR by fully automated immunohistochemistry was also evaluated by multiplying the percentage of cells with nuclear positivity (0-100) by their intensity (0-3) generating a score ranging from 0 to 300 (VDR-SCORE).
Results :
Squamous metaplasia was observed in 74% of the individuals with DED in contrast to 0% in the control group. In patients with DED, there was lower expression of VDR compared to the control group (VDR-SCORE: 11.2 ± 13.9 versus 80.9 ± 56; P = 0.0001). Furthermore, an inverse correlation was observed between the Nelson score and VDR-SCORE (P = 0.0001, Sp = -0.71), No correlation was observed between OSDI and VDR-SCORE.
Conclusions :
To the best of our knowledge, this is the first study to evaluate VDR in patients with DED. Patients with DED present a lower expression of VDR and this decrease was associated with a greater degree of squamous metaplasia, indicating a greater alteration of the ocular surface. However, the expression of VDR would not be related to the symptoms. The findings described support that VitD could be a therapeutic target in patients with DED.
This abstract was presented at the 2022 ARVO Annual Meeting, held in Denver, CO, May 1-4, 2022, and virtually.