Figure 2

Effects of niacinamide (NA) and undenatured type II collagen (UCII) supplementation on paw area [on days 7 (A), 14 (B), and 21 (C)] and pad width [on days 7 (D), 14 (E), and 21 (F)] in monosodium iodoacetate (MIA)-induced osteoarthritis in rats (n = 7). Representative images of the paw area and pad width measured on day 21 of the study are shown (G). Control as a non-supplemental group with no osteoarthritis-induced rats, MIA as a non-supplemental group with monosodium iodoacetate (MIA)-induced knee osteoarthritis, MIA + UCII as MIA group gavage-fed a supplemental UCII at 4 mg/kg, MIA + NA40 as MIA group gavage-fed supplemental niacinamide (NA) at 40 mg/kg, MIA + NA200 as MIA group gavage-fed a supplemental NA at 200 mg/kg, MIA + UCII + NA40 as MIA group gavage-fed both supplemental UCII at 4 mg/kg and NA at 40 mg/kg, and MIA + UCII + NA200 as MIA group gavage-fed both supplemental UCII at 4 mg/kg and NA at 200 mg/kg. Oral gavage delivery of supplements was applied from d7 to d30. ANOVA and Tukey’s post-hoc test were used for comparing the results among different treatment groups. Statistical significance between groups is shown by: *p < 0.05; **p < 0.01; ***p < 0.001; ****p < 0.0001 compared as Control group and, ^#p < 0.05; ^##p < 0.01; ^###p < 0.001; ^####p < 0.0001 compared as MIA group and, ⁺p < 0.05; ⁺⁺⁺⁺p < 0.0001 compared as MIA + UCII group and, ^⬛p < 0.05; ^⬛⬛⬛p < 0.001; ^⬛⬛⬛⬛p < 0.0001 compared as MIA + NA40 group and, •p < 0.05; ••p < 0.01; ••••p < 0.0001 compared as pairwise comparisons between the groups). (ANOVA and Tukey's post-hoc test; p < 0.05).