High-fat diets and increased lipid levels may cause meibomian gland inflammation

A murine study used induced hyperlipidemia to investigate the effects of a high-fat diet on the meibomian gland.

Study design

Two groups of mice were given either a high-fat (60% fat) or a standard (10% fat) diet for 4 to 16 weeks. A third group was given a high-fat diet and also injected with rosiglitazone 10 mg/kg once daily for 4 weeks. Fasting plasma cholesterol levels were measured, and eyelid margins and corneas were imaged. Real-time PCR and western blot tests were used to detect inflammation biomarkers in the meibomian gland.

Outcomes

A high-fat diet leading to cholesterol levels similar to that seen in humans with moderate hyperlipidemia led to meibomian gland inflammation and apoptosis, as indicated by upregulated signaling pathways and downregulated peroxisome proliferator-activated receptor gamma (PPAR-γ) expression. These inflammatory signs were alleviated by a return to a standard diet or supplementation with rosiglitazone, a PPAR-γ agonist.

Limitations

Results seen in mice cannot automatically be translated to humans. Furthermore, the investigator did not include indicators of evaporative dry eye often seen in meibomian gland dysfunction (MGD), such as tear breakup time or osmolarity.

Clinical significance

The results of this study support the notion that diet plays a significant role in meibomian gland health, and that high-fat diets may have a deleterious effect on meibomian gland function. As well, PPAR-γ agonists may be a potential treatment option for inflammation induced by a high-fat diet.