*2.3. Cell Treatments and UVA-Irradiation*

Before UVA irradiation, the cells were pre-treated with Ectoine (0.5–1.5 μM for 24 h) or vehicle (PBS). Post incubation, PBS washed cells were exposed to 3 J/cm<sup>2</sup> UVA radiations (for 27 min, λmax, 365 nm, no detectable emissions below 320 nm) using the UV CROSS-LINKER CL-508 (UVItec, Cambridge, UK) [21].
