The following is a summary of “Mid-old cells are a potential target for anti-aging interventions in the elderly,” published in the November 2023 issue of Dermatology by Kim et al.

The aging process often involves the accumulation of senescent cells within organs. However, the study conducted by the researchers has identified a distinct subset of fibroblasts and smooth muscle cells in the organ stroma of elderly individuals, which is termed “mid-old status” cells. Unlike proliferative or senescent cells, these mid-old cells exhibit a unique state neither associated with active growth nor senescence. Notably, these cells show an altered genetic profile, characterized by the upregulation of pro-inflammatory genes like IL1B and SAA1, alongside the downregulation of anti-inflammatory genes such as SLIT2 and CXCL12. Within the stroma, the upregulated SAA1 contributes to the creation of an inflammatory microenvironment by increasing the expression of MMP9. 

This results in reduced stability of epithelial cells found on the basement membrane, thereby diminishing their functionality. Interestingly, their research highlights that the changes in the microenvironment and the functional decline of mid-old cells can be reversed by a protein originating from young cells, namely SLIT2. These findings underscore the potential of reverting the functionality of mid-old cells as a strategy to potentially prevent or alleviate age-related tissue dysfunctions.

The identification of these mid-old status cells, their distinct genetic profile, and their response to protein interventions shed light on potential avenues for interventions targeting age-related tissue dysfunction. Understanding the mechanisms governing mid-old cells offers promising prospects for anti-aging interventions in the elderly.

Source: nature.com/articles/s41467-023-43491-w