Effects of selenium onPteridium aquilinumand urethane-induced lung carcinogenesis

Fabrication and in vivo evaluation of ligand appended paclitaxel and artemether loaded lipid nanoparticulate systems for the treatment of NSCLC: A nanoparticle assisted combination oncotherapy

The aim of present study was to develop folate appended PEGylated solid lipid nanoparticles(SLNs) of paclitaxel(FPS) and artemether(FAS). The SLNs were prepared by employing high pressure homogenization technique. The results of MTT assays revealed better cytotoxicity of FPS when given in combination with FAS on human lung cancer cell line H-1299 as compared to pure drugs, unconjugated SLNs and FPS alone. The cellular uptake of FPS and FAS was confirmed by fluorescence imaging and flow cytometric analysis. In-vivo pharmacokinetic study revealed better absorption and long circulation of FPS and FAS, which further leads to increased relative bioavailability of drugs(13.81-folds and 7.07-folds for PTX and ART, respectively) as compared to their solutions counterpart. In-vivo pharmacodynamic study confirmed tumor regression of developed SLNs formulations, which was observed highest when used in combination of FPS and FAS. Serum creatinine, blood urea nitrogen(BUN), SGOT, albumin and total protein levels revealed that formulated FPS and FAS does not exhibit any renal and hepatic toxicity. It can be concluded that by administering ART-SLNs along with PTX-SLNs via oral route, anticancer potential of PTX was improved without any toxicity (both renal, hepatic), thus, indicating the potential of developed formulations in reducing dose related toxicity of PTX.

The role of bracken fern illudanes in bracken fern-induced toxicities

Bracken fern is carcinogenic when fed to domestic and laboratory animals inducing bladder and ileal tumours and is currently classified as a possible human carcinogen by IARC. The carcinogenic illudane, ptaquiloside (PTQ) was isolated from bracken fern and is widely assumed to be the major bracken carcinogen. However, several other structurally similar illudanes are found in bracken fern, in some cases at higher levels than PTQ and so may contribute to the overall toxicity and carcinogenicity of bracken fern. In this review, we critically evaluate the role of illudanes in bracken fern induced toxicity and carcinogenicity, the mechanistic basis of these effects including the role of DNA damage, and the potential for human exposure in order to highlight deficiencies in the current literature. Critical gaps remain in our understanding of bracken fern induced carcinogenesis, a better understanding of these processes is essential to establish whether bracken fern is also a human carcinogen.

Ethyl carbamate: An emerging food and environmental toxicant

Ethyl carbamate (EC), a chemical substance widely present in fermented food products and alcoholic beverages, has been classified as a Group 2A carcinogen by the International Agency for Research on Cancer (IARC). New evidence indicates that long-term exposure to EC may cause neurological disorders. Formation of EC in food and its metabolism have therefore been studied extensively and analytical methods for EC in various food matrices have been established. Due to the potential threat of EC to human health, mitigation strategies for EC in food products by physical, chemical, enzymatic, and genetic engineering methods have been developed. Natural products are suggested to provide protection against EC-induced toxicity through the modulation of oxidative stress. This review summarizes knowledge on the formation and metabolism of EC, detection of EC in food products, toxic effects of EC on various organs, and mitigation strategies including prevention of EC-induced tumorigenesis and genotoxicity by natural products.

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 current study aimed to develop gold nanoparticles (GNPs) and liposome-embedded gold nanoparticles (LGNPs) as drug carriers for temozolomide (TMZ) and investigate the possible therapeutic effects of intratracheal inhalation of nanoformulation of TMZ-loaded gold nanoparticles (TGNPs) and liposome-embedded TGNPs (LTGNPs) against urethane-induced lung cancer in BALB/c mice. Physicochemical characters and zeta potential studies for gold nanoparticles (GNPs) and liposome-embedded gold nanoparticles (LGNPs) were performed. The current study was conducted by inducing lung cancer chemically via repeated exposure to urethane in BALB/C mice. GNPs and LGNPs were exhibited in uniform spherical shape with adequate dispersion stability. GNPs and LGNPs showed no significant changes in comparison to control group with high safety profile, while TGNPs and LTGNPs succeed to improve all biochemical data and histological patterns. GNPs and LGNPs are promising drug carriers and succeeded in the delivery of small and efficient dose of temozolomide in treatment lung cancer. Antitumor activity was pronounced in animal-treated LTGNPs, these effects may be due to synergistic effects resulted from combination of temozolomide and gold nanoparticles and liposomes that may improve the drug distribution and penetration.

The Epidemiology of Selenium and Human Cancer

The relation between selenium and cancer has been one of the most hotly debated topics in human health over the last decades. Early observational studies reported an inverse relation between selenium exposure and cancer risk. Subsequently, randomized controlled trials showed that selenium supplementation does not reduce the risk of cancer and may even increase it for some types, including advanced prostate cancer and skin cancer. An increased risk of diabetes has also been reported. These findings have been consistent in the most methodologically sound trials, suggesting that the early observational studies were misleading. Other studies have investigated selenium compounds as adjuvant therapy for cancer. Though there is currently insufficient evidence regarding the utility and safety of selenium compounds for such treatments, this issue is worthy of further investigation. The study of selenium and cancer is complicated by the existence of a diverse array of organic and inorganic selenium compounds, each with distinct biological properties, and this must be taken into consideration in the interpretation of both observational and experimental human studies.

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

AIMS

Paraquat Poisoning (PQ) can cause illness and death, and its main causes of mortality are acute respiratory failure and lung fibrosis. Early recognition of this condition and early treatment are vital. Thus, it is of importance to target the key genes controlling pathogenesis in the early stage of PQ.

MAIN METHODS

C57BL/6 mice were used for Paraquat intragastric administration as a model of PQ. Following a gene chip-based screening, the change of gene expression in the lung was further validated by bioinformatic analyses, co-expression network construction and real-time RT-PCR, Western blot and immunofluorescence assays.

KEY FINDINGS

2287 genes with differential expression were identified at the very early stage of PQ. From these, 76 genes that were linked to mitochondrion function were further pursued. Among these genes, PSTK was a phosphorylase kinase which serves a protective role in oxidative stress lung damage. PSTK was the central gene in a 30-gene network that is important for mitochondrial complex I assembly, mitochondrial apoptosis and mitochondrial fatty acid beta-oxidation, suggesting that they could conceivably be related to the pathogenesis of PQ induced lung damage. Lastly, we confirmed that PSTK was lowered in rodent lungs following PQ.

SIGNIFICANCE

PSTK emerges as a central gene in a network of mitochondrial function genes in PQ exposed mice. The functional role of PSTK in PQ induced lung injury warrants further examination.