They found that increased Hh signaling is a hallmark of human meibomian gland carcinoma, a rare and aggressive cancer of the eyelid. Furthermore, the team discovered that aged glands show decreased Hh signaling and decreased epidermal growth factor receptor (EGFR) signaling, as well as impaired innervation and a loss of collagen in niche fibroblasts, suggesting that changes in both glandular epithelial cells and their surrounding microenvironment contribute to age-related degeneration.

These discoveries suggest that targeting Hh and EGFR signaling to stimulate stem cell activity in the meibomian glands could be a potential therapeutic option to treat evaporative dry eye disease.

A team of researchers has identified stem cell populations and mechanisms underlying age-related degeneration in glands that are vital to eye function. The findings, published in Nature Communications, may lead to new therapeutic approaches for evaporative dry eye disease, a common condition in older people.

Meibomian glands, tiny oil glands along the edges of the eyelids, secrete lipid-rich meibum to prevent tear evaporation and protect the eye surface. Aging-related shrinkage of the meibomian glands may result, in part, from stem cell exhaustion and is associated with evaporative dry eye disease, a common condition that causes swollen eyelids, itchy eyes, or blurred vision. Symptoms may be lessened with warm compressions, artificial tears, and thermal pulsation, but these treatments are only partially effective.

The researchers identified markers for stem cell populations that maintain distinct regions of the meibomian glands, and uncovered the hedgehog (Hh) cell-cell signaling pathway, which is broadly important in development and disease, as a key regulator of meibomian gland stem cell proliferation and tissue regeneration.

With clinical trials results trickling in, “antiaging” drugs that clear away senescent cells are proving to be promising — and confounding.

Researchers have shed new light on how tissues in the body are repaired following the damage and premature death of tissue cells.

Their study in fruit flies, which first appeared in eLife as a Reviewed Preprint and is now published as the final version, describes what the editors call fundamental discoveries with solid evidence for how dying (or necrotic) cells contribute to tissue regeneration through a previously uncharacterized mechanism. It suggests that these cells play a role in signaling for the body to produce other types of cells that are involved in controlling natural cell death and inflammation, with findings that may have implications for wound repair and tissue regeneration.

As our bodies grow and develop, cells naturally die off where they are no longer needed, in a process called apoptosis. On the other hand, cells can be damaged and die prematurely due to injury, infectious diseases or other factors, in a process known as necrosis.