Modulation of Cell Cycle Profile by Chlorella vulgaris Prevents Replicative Senescence of Human Diploid Fibroblasts

Figure 3

DNA damage. The cell nuclei were classified into five categories: (Score 0), undamaged (nuclei without comet tail); (Score 1), low damaged (nuclei with comet tails up to two- fold longer than nucleus diameter); (Score 2), damaged (nuclei with comet tail two- to threefold longer than nucleus diameter); (Score 3), highly damaged (nuclei with comet tails threefold longer than nucleus diameter); and (Score 4), severely damaged (cell nuclei were almost not visible with long and dispersed comet tails).