Effects of Roscovitine and Serum Starvation on the Viability and G0/G1 Synchronization in Somatic Cells from the Antillean Manatee (Trichechus manatus manatus, Linnaeus 1758).

The success of nuclear reprogramming techniques, including the G0/G1 synchronization of somatic cells, depends on species-specific optimization. While roscovitine and serum starvation have been successfully applied in domestic and wild terrestrial mammals, their use in aquatic mammals remains poorly investigated. The development of cellular reprogramming protocols in Antillean manatees, a flagship and endangered aquatic species, represents a promising tool for advancing conservation efforts. This study evaluated the effects of 10 µM roscovitine (12 and 24 h) and serum starvation (0.5% serum for 24 h) on G0/G1 phase synchronization and viability in somatic cells of the Antillean manatee using flow cytometry. Additionally, we assessed cell morphology, viability, and apoptosis through microscopy-based analyses. The results showed that neither serum starvation (68.4%) nor roscovitine treatment (12 h: 84.3%; 24 h: 79.3%) enhanced G0/G1 synchronization compared to the control group (83.4%). Serum starvation significantly reduced the proportion of G0/G1-phase cells compared to the 12 h roscovitine group and the control (p < 0.05). No differences were observed in morphology or viability across groups (p > 0.05). However, extended exposure to roscovitine (24 h) increased apoptotic markers compared to the control group. In summary, although roscovitine (12 h) and serum starvation did not compromise cell viability, neither method effectively induced G0/G1 synchronization under the conditions tested. Studies are needed to elucidate the in vitro behavior of Antillean manatee somatic cells and to optimize protocols for nuclear reprogramming applications.