ascorbic-acid and Silicosis

Workers involved in mining activities are exposed to crystalline silica, which leads to constant pulmonary inflammatory reactions and severe oxidative damage, resulting in silicosis. In this work, we aimed to evaluate inflammatory and oxidative stress parameters as potential early biomarkers of effect to assess crystalline silica toxicity in workers who had occupational exposure during mining. We enrolled 38 workers exposed to crystalline silica (WECS), 24 individuals with silicosis (IWS), and 30 occupationally unexposed workers (OUW), a total of 92 participants. The WECS were divided into 2 groups, according to the time of exposure: 19 workers with 1-15 years of occupational exposure (WECS I) and 19 workers with >16 years of occupational exposure (WECS II). The inflammatory parameters assessed were L-selectin, β-2 integrin, and intercellular adhesion molecule-1 (ICAM-1) surface protein expression in lymphocytes and monocytes, complement C3 and C4, high sensitivity C-reactive protein (hsCRP), and adenosine deaminase (ADA) in serum. Plasma levels of malondialdehyde (MDA) and serum levels of vitamin C were determined as biomarkers of oxidative stress. Biochemical and hematological parameters were also investigated. L-selectin surface protein expression was significantly decreased in the WECS II group (p < 0.05), indicating the importance of this immune system component as a potential marker of crystalline-silica-induced toxicity. The MDA levels were significantly increased in the WECS I, WECS II, and IWS groups compared to the OUW group (p < 0.05). Vitamin C levels were decreased, while C3, hsCRP, ADA, and aspartate aminotransferase (AST) levels were increased in the IWS group compared to the OUW group (p < 0.05). Glucose and urea levels were significantly higher in the WECS I, II, and IWS groups compared to the OUW group (p < 0.05). Negative partial association was found between L-selectin and time of exposure (p < 0.001), supporting the relevance of this biomarker evaluation in long-term exposure to crystalline silica. Significant associations were also observed among inflammatory and oxidative stress biomarkers. Therefore, our results demonstrated the relevance of L-selectin as a potential peripheral biomarker for monitoring crystalline silica-induced toxicity in miners after chronic exposure, before silicosis has developed. However, more studies are necessary for better understanding of the use L-selectin as an early biomarker in exposed workers.

Topics: Ascorbic Acid; Biomarkers; Humans; Inflammation; Malondialdehyde; Oxidative Stress; Silicosis

To explore the effect of tea polypheonls (TP) combined with ascorbic acid on the activity of antioxidant enzymes of rats induced by silica, the activities of nitric oxide synthase (NOS), glutathione peroxidase (GSH-PX) and superoxide dismutase (SOD) were determined. Compared with the normal saline control group, the activities of SOD and NOS of the silica-induced group increased (P < 0.05), but the activity of GSH-PX was gradually decreased. The activities of SOD and NOS decreased and GSH-PX increased in the intervention group. It is concluded that TP combined with ascorbic acid can alleviate the abnormal change of antioxidant enzymes in rats induced by silica.

Topics: Animals; Ascorbic Acid; Flavonoids; Glutathione Peroxidase; Male; Nitric Oxide Synthase; Phenols; Polymers; Polyphenols; Random Allocation; Rats; Rats, Wistar; Silicosis; Superoxide Dismutase; Tea

Plasma vitamin C(P-VC), vitamin E(P-VE) and beta-carotene(P-beta-CAR) contents and the activities of superoxide dismutase(E-SOD), catalase(E-CAT) and glutathione peroxidase (E-GSH-Px) in erythrocyte in 73 silicosis patients and 60 healthy control subjects were measured. The average levels of P-VC, P-VE, P-beta-CAR, E-SOD, E-CAT and E-GSH-Px of patients were significantly lower than those of the controls (P < 0.001). All indexes were correlated to the course, condition and pulmonary function of silicosis patients. The results analyzed by stepwise regression showed that the correlation between course, condition and pulmonary function of patients and P-VE and E-SOD was close. The balance between oxidation and the antioxidation in silicosis patients may be disturbed, and oxygen free radical reaction may be pathologically exacerbated.

Topics: Adult; Aged; Antioxidants; Ascorbic Acid; Catalase; Erythrocytes; Humans; Middle Aged; Respiratory Function Tests; Silicosis; Superoxide Dismutase; Vitamin E

To explore the relationship between nitric oxide, oxidation, lipoperoxidation and silicosis.. Blood plasma levels of nitric oxide (P-NO), vitamin C (P-VC), vitamin E (P-VE), beta-carotene (P-beta-CAR), lipoperoxidase (P-LPO), and erythrocyte activities of superoxide dismutase (E-SOD), catalase (E-CAT), glutathione peroxidase (E-GSH-Px) and lipoperoxidase (E-LPO) were measured in 73 patients with silicosis and 60 healthy subjects.. The average levels of P-VC, P-VE, P-beta-CAR, E-SOD, E-CAT and E-GSH-Px were significantly lower and the average levels of P-NO, P-LPO and E-LPO significantly increased in the silicosis with varied severity of the disease and lung function status more than in the controls. There was linear relationship between all the above indices and length of the disease. Stepwise regression analysis showed that the severity of the disease and lung function status correlated most closely with the levels of P-NO, P-VE, E-SOD and E-LPO.. Metabolism of nitric oxide was abnormal, balance between oxidation and antioxidation was disturbed seriously, and oxidation and lipoperoxidation reaction pathologically exacerbated in the bodies of the patient with silicosis.

Topics: Adult; Aged; Ascorbic Acid; Humans; Lipid Peroxides; Male; Middle Aged; Nitric Oxide; Oxidation-Reduction; Regression Analysis; Sampling Studies; Silicosis; Superoxide Dismutase

Topics: Adult; Ascorbic Acid; beta Carotene; Bronchitis; Carbon; Carotenoids; Diamond; Humans; Middle Aged; Mining; Siberia; Silicosis; Vitamin A

Topics: Animals; Ascorbic Acid; Collagen; Disease Models, Animal; Hydroxyproline; Iron; Ketoglutaric Acids; Mixed Function Oxygenases; Proline; Pulmonary Fibrosis; Rats; Silicosis

Topics: Animals; Ascorbic Acid; Capillary Permeability; Drug Synergism; Flavonoids; Rats; Silicosis

Topics: Adrenal Glands; Animals; Ascorbic Acid; Collagen; Guinea Pigs; Histocytochemistry; Lung; Methods; Scurvy; Silicon Dioxide; Silicosis; Silver

Topics: Adult; Aerosols; Ascorbic Acid; Bronchitis; Dermatologic Agents; Dust; Humans; Infections; Inflammation; Middle Aged; Occupational Diseases; Silicosis; Tannins

Topics: Adult; Aged; Ascorbic Acid; Humans; Injections, Intravenous; Lymphocytes; Male; Middle Aged; Muramidase; Silicosis

Topics: Aerosols; Animals; Ascorbic Acid; Ascorbic Acid Deficiency; Bicarbonates; Collagen; Connective Tissue; Diet; Guinea Pigs; Hexosamines; Lung; Organ Size; Silicon Dioxide; Silicosis; Time Factors

Topics: Animals; Ascorbic Acid; Carbon Isotopes; Collagen; Dust; Granuloma; Guinea Pigs; Hydroxyproline; Liver; Lung; Muscles; Organ Size; Proline; Silicon Dioxide; Silicosis

Topics: Adrenal Glands; Ascorbic Acid; Blood; Dust; Humans; Mining; Pathology; Pituitary-Adrenal Function Tests; Silicosis

Topics: Alanine Transaminase; Animals; Ascorbic Acid; Aspartate Aminotransferases; D-Alanine Transaminase; Guinea Pigs; Histocytochemistry; Lung; Pulmonary Fibrosis; Research; Silicosis

Topics: Adrenal Cortex; Ascorbic Acid; Pharmacology; Pituitary-Adrenal Function Tests; Pneumoconiosis; Silicosis

Topics: Ascorbic Acid; Collagen Diseases; DNA; Eukaryota; Granulation Tissue; Granuloma; Guinea Pigs; Inflammation; Rats; Research; Silicosis; Toxicology

Topics: Ascorbic Acid; Collagen; Connective Tissue; Histocytochemistry; Leukocytes; Lung; Rats; Research; Silicosis

Topics: Adolescent; Adrenal Insufficiency; Ascorbic Acid; Blood Chemical Analysis; Child; Geriatrics; Silicosis