In non-diabetic mice, preserved Brn3A+ cells were significantly greater in group 2 (2382 ± 140 Brn3A+ cells/mm2, n = 7) than in group 1 (1920 ± 228 Brn3A+ cells/mm2; p = 0.03, n = 4), group 3 (1938 ± 213 Brn3A+ cells/mm2; p = 0.002, n = 4), and group 4 (2138 ± 126 Brn3A+ cells/mm2; p = 0.03, n = 4), respectively; PGZ confers protection to RGCs from damage caused by ischemic optic neuropathy in diabetic and non-diabetic mice. The gene discussed is POU4F1; the disease is anterior ischemic optic neuropathy.