Effects of selenium onPteridium aquilinumand urethane-induced lung carcinogenesis

Abstract

The results of our previous study demonstrated that ptaquiloside, the main toxic agent found in Pteridium aquilinum, suppresses natural killer (NK) cell-mediated cytotoxicity. However, the ability of ptaquiloside to suppress the cytotoxicity of NK cells was prevented by selenium supplementation. NK cells play an important role in the innate immune response and have the ability to kill tumor cells. Therefore, we hypothesized that selenium may prevent the higher susceptibility to urethane-induced lung carcinogenesis that has been observed in mice treated with P. aquilinum. The immunosuppressive effects of ptaquiloside have been associated with a higher number of urethane-induced lung nodules in mice. Hence, we assessed the effects of P. aquilinum-induced immunosuppression on urethane-induced lung carcinogenesis in C57BL/6 mice that had been supplemented with selenium. For these experiments, mice were treated with both an aqueous extract of P. aquilinum (20 g/kg/day) and selenium (1.3 mg/kg) by gavage once daily for 14 days followed by a once-weekly intraperitoneal injection of urethane (1 g/kg) for 10 weeks that was accompanied by gavage 5 days a week. Lung adenomas in mice that had been treated with P. aquilinum plus urethane occurred with a frequency that was 44% higher than that in mice that had been treated with only urethane. In mice that had been supplemented with selenium and treated with P. aquilinum plus urethane, the occurrence of lung adenomas was reduced to 26%. These results suggest that selenium prevents the immunosuppressive effects of P. aquilinum on urethane-induced lung carcinogenesis.

An Additional risk of Lung Cancer from Recurrent Exposure to Ethyl Carbamate (EC) in BALB/C Mice

“…They play a major role in pulmonary inflammation and adenocarcinoma [27]. It has been well documented that the molecular mechanism of ethyl carbamateinduced lung cancer is based on integration of TNF signals with NF-кB that accelerate tumour progression [28]. Histological studies confirmed the biochemical results of the current work.…”

PSTK is a novel gene associated with early lung injury in Paraquat Poisoning

“…All the GO terms assigned to these genes were examined, and obtained by Fisher's exact test and x 2 test for calculating the level of significance as described [16,17].…”

Antitumor activity of intratracheal inhalation of temozolomide (TMZ) loaded into gold nanoparticles and/or liposomes against urethane-induced lung cancer in BALB/c mice

“…The results were in agreement with earlier studies that postulated urethane induce over expression of key molecules such as NF-κB, Stat3, pStat3; IL-1β, those play a major role in chronic inflammation and lung adenocarcinoma (Bernert et al, 2003 ). The molecular mechanism of urethane-induced lung cancer based on integration of TNF signals with NF-кB that accelerate tumor progression (Nakahara et al, 2013 ). Intratracheal inhalation of either GNPs or LGNPs showed non-significant difference in LDH, CEA and AFP in comparison to control group.…”