Ginseng ameliorates pulmonary toxicity induced by silicon dioxide nanoparticles in rats

Objective:To investigate the protective and therapeutic role of ginseng against silicon dioxide nanoparticles(SiO2NPs)-induced toxicity in the lungs.Methods:Sixty male rats were divided into five groups(n=12/group);group 1 was used as a control,group 2 received ginseng,group 3 was treated with SiO2NPs,and group 4 was pretreated with ginseng one week before SiO2NPs,while group 5 was given SiO2NPs one week before supplementation with ginseng.Animals were treated with both ginseng and SiO2NPs orally for five weeks.Real-time PCR was used to measure gene expression.Besides,DNA damage and cell cycle changes were determined by comet assay and flow cytometry,respectively.Histological study was also done to assess the effect of ginseng on SiO2NPs-induced toxicity.Results:SiO2NPs increased lipid peroxidation and decreased the activities of antioxidant enzymes.SiO2NPs induced apoptosis in lung tissues as revealed by upregulation of Bax and caspase 3 and downregulation of Bcl-2 as well as the induction of DNA damage.SiO2NPs also caused inflammation as indicated by upregulation of the inflammation-related genes[interleukin 1 beta(IL-1β),tumor necrosis factor-alpha(TNF-α),nuclear factor kappa B(NF-κB),cyclooxygenase 2(COX2),and transforming growth factor-beta 1(TGFβ1)]as well as cell cycle arrest in the G0/G1 phase of lung cells.Moreover,histopathological examination proved the biochemical and molecular perturbations that occurred due to SiO2NPs toxicity.However,ginseng alleviated SiO2NPs-induced toxicity in rat lung.Conclusions:Ginseng has a potent preventive and therapeutic effect and could be used in the treatment of SiO2NPs-induced pulmonary toxicity.

Impact of Traffic Emissions on Local Air Quality and the Potential Toxicity of Traffic-related Particulates in Beijing, China

Objective Air-borne particulates from different sources could have different physicochemical properties and inflammatory potentials. This study aims to characterize the chemical compositions and the toxicity of ambient particulate matter （PM） associated with traffic emissions. Methods The concentrations of trace elements, organic carbon （OC）, elemental carbon （EC） and polycyclic aromatic hydrocarbons （PAHs） in PM2.5 and PMlo were measured in samples collected at sites in Beijing, China. Their toxic effects on the pulmonary system of rats were investigated. Biochemical parameters （LDH, T-AOC, TP） and inflammatory cytokine（IL-6, IL-1, TNF-a） levels were measured in the lungs of rats exposed to traffic-related PM. Oxidative damage was observed. PM samples were taken from a near road site and an off road site in summer time in 2006. Results The concentrations of the USEPA priority pollutant PAHs in both PMlo and PM2.s were higher （299.658 and 348.412） at the near road site than those （237.728 and 268.472） at the off road site. The similar trend was observed for the concentrations of trace elements in PM. Compared to coarse particles （PM^0）, fine particles （PM2.s） have a greater adsorption capacity to enrich toxic elements than inhalable particles. Decrease in antioxidant capacity and an increase in the amount of lipid peroxidation products in rat lung tissues was observed. Conclusion The findings of the present study suggest that the differing inflammatory responses of PM collected from the two road sites might have been mediated by the differing physicochemical characteristics.

EFFECTS OF INHALED TiO_2 NANOTUBES ON LUNG TISSUE AND SERUM BIOCHEMICAL INDEXES OF MICE

To evaluate the acute lung toxicity and the effect on serum biochemical indexes of inhaled TiO2 nanotubes , healthy and adult Kunming mice are exposed to aerosols of TiO2nanotubes in a sealed chamber , the concentration of which is 250mg / m 3 while another group of mice are exposed to room air only served as control.The blood , alveolar lavaged fluid and lungs of the mice are collected and examined after exposed for 7 , 14and 28d , respectively.The serum analysis shows that glucose ( Glu ) values with 7dexposure , alanine aminotransferase ( ALT ) and aspartate aminotransferase ( AST ) activities with 28dinhalation , and total bile acid ( TBA ) values with 7 , 28d as well as the creatine kinase ( CK ) levels with 28dexposure are significantly different from those of controls ( P< 0.05 ) .The pathological findings exhibit that more TiO 2 nanotubes are found in the interstitium of pulmonary alveoli with the experimental time prolonged.The results suggest that TiO 2 nanotubes do produce adverse responses to the lung and serum biochemical indexes of mice.Moreover , the responses become severer with the exposed-time prolonged.

The Physical and Chemical Properties of Cooking Oil Vapor and Its Biological Effects

The paper discussed the physical and chemical properties of cooking oil vapor(COV) and its biological effects. The study showed that: (1)By ultraviolet spectrophotometry, the method to determine the concentration of COV was simple, reliable and suitable; (2)At 220℃, about 60%-80% particles′ diameter of COV were less than 10 μm which referred to they are capable of reaching the deeper parts of the respiratory tract; (3)Pulmonary toxicity study of COV revealed that in acute toxicity test, there was lung tissue injury in rats and the degree increased as the concentration of oil vapor increased; subacute test in rats indicated that pulmonary injury might be the result of lipid peroxidation brought about by the activation of more general free radical system; (4)The average concentration of emitted oil vapor in the environment ranged from 0.10 to 0.20 mg/m3, the emission outlets in most restaurants were very simple or located in residential areas without any filtering device; (5)Irritative effect threshold levels of COV to volunteers and the effects on occupational exposed cooks also suggested that COV might produce harmful effects on pulmonary function in occupationally exposed personnel.