Caffeine alters the effects of bone marrow-derived mesenchymal stem cells on neutrophils

It has been shown that mesenchymal stem cells (MSCs) express all four adenosine receptors' subtypes, and stimulation of these receptors plays an active role in bone marrow-derived mesenchymal stem cell proliferation and differentiation. The interaction between MSCs and immunocytes, such as neutrophils, has been investigated in some recent studies.

This study was carried out to investigate the effects of caffeine as an adenosine antagonist on the effects of bone marrow-derived MSCs on neutrophils.

Mesenchymal stem cells were isolated from the bone marrow of rats and pulsed with different concentrations of caffeine (0.1, 0.5 and 1 mM) at different times (24, 48 and 72 h). Mesenchymal stem cells were co-cultured with neutrophils for 4 h and the functions of neutrophils were evaluated.

The findings showed that MSCs pulsed with caffeine at low to moderate concentrations preserved the neutral red uptake by neutrophils and established the MSCs' ability to protect neutrophils from apoptosis. Mesenchymal stem cells treated with caffeine increased the phagocytosis of neutrophils and simultaneously diminished the production of potentially harmful reactive oxygen substances, more profound than MSCs without treatment. Nevertheless, a high concentration of caffeine could interfere with some aspects of the crosstalk between MSCs and neutrophils.

These findings may offer new insight into the potential mechanisms underlying the immunomodulatory effects of caffeine.