Abstract
Purpose :
Hyaluronic acid (HA) is a natural glycosaminoglycan polymer, produced endogenously in human skin, joints, eyes and other issues. HA loss can cause different physiological diseases with increasing age. The oral HA replenishment had been proved effective in improving corneal epithelial wound healing as well as other related ocular diseases. This paper aims to investigate whether Hyaluronic Acid (HA) with different molecular weight(MW) can protect the cornea in a benzalkonium chloride (BAC)-induced mice dry eye model.
Methods :
Fifty-six female C57BL6/J mice (18-20 g) were used for this study. The experimental protocol was approved and had obtained audit number as JN.No20210330i0560901[064] from IACUC Issue. Every mice was checked for none ocular surface disorders in advance and were randomly divided into 7 groups : control group, model group, HA-1 (80-100 kda) group, HA-2 (200-400 kda ) group, HA-3 (500-700 kda), HA-4 (800-1000 kda ), HA5 (1000-1300 kda ) group. The dosage of different MW HA was 30 mg/kg/day and the intervention lasted for 42 days. The eyes were topically administered with 10ul of 0.05% BAC for 20 days twice daily (9 am, 9 pm) to create the dry eye condition except control group. The Fluorescein staining, tear break-up time (BUT), and tear fluid were evaluated on the ocular surface. Inflammatory factor level of TNF-α, IL-1β and content of HA in eyeballs was detected.
Results :
HA with MW 200-400, 500-700, 800-1000, 1000-1300 kDa could significantly increase the tear film rupture time and improve the stability of the tear film in mice. The HA treated in the MW range of 800-1000, 1000-1300 kDa has no obvious effect on tear secretion, and HA of 80-100, 200-400, 500-700 kDa can promote the secretion of tear volume. The corneal coloration in each group of HA intervention decreased compared with model group. Altogether, HA with 200-400 kda MW resulted in significantly longer tear break-up time, lower fluorescein staining scores and more tear fluid secretion. In addition, Benzalkonium chloride moldings induced an increase of inflammatory factors TNF-α and IL-6 in the eyeball. HA exerting the effect of reducing inflammatory factors and the MW of 200-400 kda HA was the most prominent. Moreover 200-400 HA oral treated could improve eye endogenous HA content in our research.
Conclusions :
HA with 200-400 kda MW is a potential active substance for the treatment of dry eye disease.
This abstract was presented at the 2023 ARVO Annual Meeting, held in New Orleans, LA, April 23-27, 2023.