Programmed cell death evidence in wheat (Triticum aestivum L.) roots induced by aluminum oxide (Al₂O₃) nanoparticles

Figures & data

Table 1. The effects of Al₂O₃ NP (5, 25 and 50 mg ml^–1) on the mitotic index, chromosome abnormalities and micronuclei in wheat roots after 96 h. The data with different letter are significantly different according to Tukey’s post-hoc HSD test for independent samples at p < 0.05. Values represent means ± SD.

	Control	5 mg ml^–1	25 mg ml^–1	50 mg ml^–1
Total cell number	1138	1255	1182	1067
% Mitotic index (±SD)	20.94^a ±11.8	15.90^ab ±10.3	13.15^b ±11.7	12.82^b ±10.0
‰ Micronucleus	—	6.4^b ±1.8	7.6^a ±1.1	6.6^b ±1.5
‰ C-mitosis	—	2.4^b ±1.2	7.6^a ±0.9	1.9^b ±0.9
‰ Stickiness	—	—	2.5 ±0.6	—
‰ Monopolar metaphase	—	0.8^b ±0.1	2.6^a±0.5	0.9^b ±0.3
Total abnormalities (‰)	—	9.6^b ±3.1	20.3^a ±3.1	9.4^b ±2.7

Figure 1. Micronuclei and chromosomal abnormalities in Al₂O₃ NP (5, 25 and 50 mg ml^–1) treated wheat roots after 96 h. (a) Micronuclei in the 5 mg ml^–1 (arrows) treatment; (b) C-mitosis in the 25 mg ml^–1 treatment; (b) stickiness in the 25 mg ml^–1 treatment; (c) monopolar metaphase in the 25 mg ml^–1 treatment; (d) monopolar metaphase in the 50 mg ml^–1 treatment. Scale bar = 10 μm.

Figure 2. Immunostaining of microtubule structures in control and Al₂O₃ NP (5, 25 and 50 mg ml^–1) treated wheat roots after 96 h. (a) Control; (b) 5 mg ml^–1; (c) 25 mg ml^–1; (d) 50 mg ml^–1. Arrows show microtubule disruption. Scale bar = 50 μm.

Figure 3. Loss of plasma membrane integrity in control and Al NP-treated wheat roots after 96 h. All data are significantly different from the control at the p < 0.05 level.

Figure 4. Control and Al₂O₃ NP (5, 25 and 50 mg ml^–1) treated wheat root cells stained with DAPI. (a) Spherical nucleus in control. (b–d) Nucleus degenerations (arrow) in (b) the 5 mg ml^–1 treatment; (c) the 25 mg ml^–1 treatment; and (d) the 50 mg ml^–1 treatment. Scale bar = 10 μm.

Figure 5. TUNEL staining of control and Al₂O₃ NP (5, 25 and 50 mg ml^–1) treated wheat roots after 96 h. a. Control (no reaction), b. 5 mg ml^–1 c. 25 mg ml^–1 d. 50 mg ml^–1. Arrows show TUNEL positive nuclei. Scale bar = 50 μm.

Figure 6. The % fold increase of caspase-3, -8 and -9 activities in control and Al NP-treated wheat roots after 96 h.