Effect of oxidative stress on development of silicosis

Table 1 Comparison of general indicators between control group, dust-exposed group and silicosis patient group

Group	n	Age (yr)	Systolic pressure (mmHg)	Diastolic pressure (mmHg)	Blood glucose (mmol/L)	Triglyceride (mmol/L)	Cholesterol (mmol/L)	Creatinine (μmol/L)	Urea nitrogen (mmol/L)	Alanine transarninase (mmol/L)
Control	100	48.7 ± 8.0	130.42 ± 8.65	82.65 ± 7.68	4.93 ± 0.94	1.45 ± 0.94	5.15 ± 1.03	71.80 ± 16.50	5.53 ± 1.20	24.31 ± 17.44
Dust-exposed	200	50.8 ± 9.4	129.53 ± 9.45	84.72 ± 8.96	4.95 ± 0.79	1.52 ± 0.42	4.24 ± 0.89	69.97 ± 18.96	6.37 ± 1.16	29.16 ± 16.68
Silicosis	130	52.0 ± 10.4	131.42 ± 10.23	84.52 ± 8.14	5.06 ± 0.94	1.53 ± 0.90	4.75 ± 0.92	80.12 ± 19.10	6.47 ± 1.87	27.10 ± 16.83

Table 2 Comparison of nitric oxide, superoxide dismutase, malondialdehyde, total antioxidant capacity, nitric oxide synthase and serum glutathione peroxidase between control, dust-exposed group and silicosis patient group

Group	n	NO (μmol/L)	SOD (U/mL)	MDA (μmol/L)	T-AOC (U/mL)	NOS (μmol/L)	GSH-Px (U/mL)
Control	100	45.622 ± 24.081	75.239 ± 24.020	4.027 ± 0.822	11.639 ± 3.707	33.812 ± 6.398	223.360 ± 46.838
Dust-exposed	200	77.148 ± 30.188b	70.515 ± 20.034b	4.240 ± 1.167	11.814 ± 4.758	35.598 ± 5.664	231.164 ± 36.484a
Silicosis	130	81.162 ± 35.176b	68.209 ± 21.528b	5.054 ± 1.204ad	13.048 ± 4.153ac	36.201 ± 7.782ac	270.469 ± 39.228bd

^aP < 0.05,

^bP < 0.01 vs control group;

^cP < 0.05,

^dP < 0.01 vs dust-exposed group. NO: Nitric oxide; SOD: Superoxide dismutase; MDA: Malondialdehyde; T-AOC: Total antioxidant capacity; NOS: Nitric oxide synthase; GSH-Px: Serum glutathione peroxidase.

Table 3 Comparison of nitric oxide, superoxide dismutase, malondialdehyde, total antioxidant capacity, nitric oxide synthase and serum glutathione peroxidase between observation group and silicosis at different stages

Group	n	NO (μmol/L)	SOD (U/mL)	MDA (μmol/L)	T-AOC (U/mL)	NOS (μmol/L)	GSH-Px (U/mL)
Observation	32	74.130 ± 38.049	70.414 ± 20.036	4.489 ± 1.154	12.903 ± 3.790	35.379 ± 5.504	256.906 ± 21.418
Silicosis
Phase I	64	79.145 ± 36.149	69.215 ± 25.033	4.994 ± 1.237	12.905 ± 4.448	35.626 ± 7.234	259.594 ± 34.79
Phase II	46	80.173 ± 36.215	67.896 ± 26.018	5.038 ± 1.208	12.834 ± 3.481	36.078 ± 5.911	276.783 ± 40.969
Phase III	20	83.176 ± 34.131	67.201 ± 30.030	5.244 ± 1.127	13.993 ± 4.662	36.899 ± 4.162	290.750 ± 39.129ac

^aP < 0.05 vs observation group;

^cP < 0.05 vs phase I silicosis. NO: Nitric oxide; SOD: Superoxide dismutase; MDA: Malondialdehyde; T-AOC: Total antioxidant capacity; NOS: Nitric oxide synthase; GSH-Px: Serum glutathione peroxidase.

Table 4 Serum glutathione peroxidase Pearson correlation test

	Silicosis stage	Category	Length of dust exposure	Type of occupation
r value	0.507	0.456	0.365	0.341
P value	0.000	0.000	0.000	0.000