General and Specific Cytotoxicity of Chimeric Antisense Oligonucleotides in Bacterial Cells and Human Cell Lines

In the last two decades, antisense oligonucleotide technology has emerged as a promising approach to tackling various healthcare issues and diseases, such as antimicrobial resistance, cancer, and neurodegenerative diseases. Despite the numerous improvements in the structure and modifications of the antisense oligonucleotides (ASOs), there are still specific problems with their clinical efficacy and preclinical cytotoxicity results. To better understand the effects of the ASOs in this paper, we conducted many MTT assays to assess the general and specific cytotoxicity of four new chimeric ASOs in bacterial cells and human cell lines. We demonstrate the absence of inhibitory activity in the human pathogenic bacteria Staphylococcus aureus by non-specific ASOs. The pVEC-ASO1 and pVEC-ASO2 are designed to have no specific targets in S. aureus. They have only partial hybridization to the guanylate kinase mRNA. The pVEC-ASO3 targets UBA2 mRNA, a hallmark cancer pathology in MYC-driven cancer, while pVEC-ASO4 has no complementary sequences. We discovered some cytotoxicity of the non-specific ASOs in healthy and cancer human cell lines. The results are compared with two other ASOs, targeting specific mRNA in cancer cells. All ASOs are delivered into the cell via the cell-penetrating oligopeptide pVEC, which is attached to them. We draw a good correlation between the thermodynamic stability of ASO/target RNA and the toxicity effect in human cell lines. The data obtained signify the importance of thorough bioinformatic analysis and high specificity in designing and developing novel ASOs for safer therapeutic agents in clinical practice.

Testing the Anticancer Effect of Matcha Using Zebrafish as an Animal Model

Cancer is the second leading cause of death worldwide, and triple-negative breast cancer (TNBC) patients show the poorest prognosis and survival and the highest metastasis prevalence among all breast cancer subtypes. Matcha has recently been associated with multiple health benefits, and in vitro studies showed the potential effect of matcha in inhibiting cancer development and metastasis. We aimed to determine the safe, non-toxic dose of matcha suitable for zebrafish and to investigate the anticancer effect of matcha on the metastasis and growth of human TBNC cells using a zebrafish xenograft model. Wild-type AB zebrafish were used to conduct multiple general toxicity assessments, including developmental, neuromuscular, and cardiovascular toxicities. The safe, non-toxic concentration of matcha was determined to be 50 µg/mL and 100 µg/mL. Afterward, the zebrafish xenograft model was successfully established for MDA-MB-468 and MDA-MB-231 TNBC cells. The tumor size and metastasis of the injected cancer cells were traced through CM-Dil red fluorescent dye. Upon exposure to matcha at the safe doses, MDA-MB-231 and MDA-MB-468 showed a trend toward reduction in tumor size in a dose-dependent manner, indicated by quantified fluorescence. Matcha also visibly suppressed metastasis of cancer cells in the zebrafish body. Our results point to a potential dose-dependent anticancer effect of matcha on TNBC cells; however, more extended observation periods after xenotransplantation are required to confirm the long-term anticancer effect of matcha on tumor growth and metastasis.

Toxicological profile of bisphenol F via comprehensive and extensive toxicity evaluations following dermal exposure

Bisphenol F (BPF) is classified as a harmful substance by the U.S. Environmental Protection Agency. Although previous studies focused on human exposure to BPF via direct consumption or inhalation, few investigators assessed potential toxicological effects following skin contact. The aim of this study was to examine (1) the degree and pattern by which BPF is absorbed onto the skin in vivo, and (2) determination of toxicity and safety using the following tests: acute dermal; a 28-day repeat dermal; a skin irritation; an eye irritation; and a skin sensitization. As indicated by the amount of BPF remaining in the epidermis or dermis, data demonstrated that BPF was absorbed through the skin at a 26.5% rate. BPF penetrated the subcutaneous layer at a "fast rate" (Kp: 2.2E-02). Although no toxicological changes or local irritation were observed following skin exposure, BPF induced potent sensitization. In summary, the findings of this study showed that BPF penetrated and was absorbed into the skin at a high rate which was associated with enhanced chemical-induced skin sensitization and this may have significant implications following exposure of skin to BPF.

Artemia species: An Important Tool to Screen General Toxicity Samples

Medicinal plants are a good source of novel therapeutic drugs, due to the phytochemicals present. Artemia, commonly known as brine shrimp, is a tiny halophilic invertebrate belonging to class Crustacean, which plays an important role in saline aquatic and marine eco-systems. Besides its usage in aquaculture, it is also highly valued for its application in toxicity detection and it is used in areas such as Ecology, Physiology, Ecotoxicology, Aquaculture and Genetics. Furthermore, Artemia based lethality assay (brine shrimp lethality assay, BSLA) is rapid, convenient and low cost. Presently, brine shrimp lethality assays are enormously employed in research and applied toxicology. It has been used in the study of natural products as a preliminary toxicity assay to screen a large number of extracts and compounds for drug discovery in medicinal plants. The aim of this review paper is to collect, organize, select and discuss the existing knowledge about the different uses of Artemia salina as a bench-top bioassay for the discovery and purification of bioactive natural products.

Effect of Pachybasin on General Toxicity and Developmental Toxicity in Vivo

To document the safety of pachybasin, a secondary metabolite of Trichoderma harzianum, for use as a bioagricultural agent, it was subjected to general toxicological testing in mice and developmental toxicity in zebrafish. With either 5 or 20 mg kg^-1 pachybasin i.p. injection, mice behavioral responses such as motor coordination, spontaneous locomotor activity, or nociceptive pain were not influenced. In long-term effect (daily injection for 14 days), the physiological, hematological, liver, and kidney functions were not altered either. Evidence for the developmental toxicity of pachybasin (10-100 μM) in 72-h exposure period was shown in zebrafish larvae, based on developmental retardation, impairment of chorion, and increase of mortality. In summary, there are no significant general toxicities presented in the pachybasin-treated adult male mice. However, the embryo-toxicity in aquatic biota should be taken into consideration during bioagricultural agent application.

In-vitro Bioactivity and Phytochemical Screening of Extracts from Rhizomes of Eremostachys azerbaijanica rech. f. Growing in Iran

The current study evaluated the general toxicity, antioxidant, antimicrobial, and cytotoxic activity of extracts obtained from the rhizomes of Eremostachys azerbaijanica (Labiatae) as well as analyzed the potent extracts using GC-MS. Extracts of E. azerbaijanica in n-hexane, dichloromethane (DCM) and methanol (MeOH) were prepared using a Soxhlet apparatus. The antioxidant activity of the extracts was evaluated for free radical scavenging activity by DPPH assay. The antimicrobial activity of samples was determined by disc diffusion and brine shrimp lethality assay (BSLA) was used to assess general toxicity. The cytotoxicity of each extract was determined by MTT assay against human colorectal adenocarcinoma (HT29), human lung carcinoma (A549) and a normal cell line (human umbilical vein endothelial cells, HUVEC). The MeOH extract showed significant antioxidant activity and the n-hexane and DCM extracts showed promising activity against gram-positive species when compared with amikacin as a standard. Moreover, the n-hexane extract displayed the most potent activity in general toxicity assay. The results showed that all three extracts have cytotoxic effects against the A549 cell line. In the case of HT29 cell lines, only the DCM extract exhibited cytotoxicity. Interestingly, none of the extracts showed significant cytotoxic activity against the HUVEC cell line. The bioassay-guided identification of constituents showed the presence of fatty acids and steroids as the compounds responsible for bioactivity in the non-polar extracts.

Chemical Composition and Biological Activities of Methanolic Extract of Scrophularia Oxysepala Boiss

Isolated five known iridoids glycosides (Scrophuloside A, Harpagoside B, 5-hydroxyloganin, 8-O-acetylharpagide and 6-O-methyl,1-glucopyranosyl catalpol), one phenyl ethanoid glycoside (Verbascoside) and a phenyl ethanol amine (2-(4-Chlorobenzyl amino) ethanol) compound from the methanolic extract of aerial parts of Scrophularia oxysepala using by high performance liquid chromatographyare based on isocratic and liner gradients by C18 column. The structure elucidations of the isolated compounds were performed by spectroscopic methods including1H-NMR, 13C-NMR, 2 D NMR technique such as HMBC( in deuterated methanol as solvent), GC-MS and UV, also methanolic extract and fractions( fractionated on solid phase extraction on C18 cartridge(Spack-C18)) of this plant was tested for free radical scavenging properties toward the 1, 1-diphenyl-1-picrylhydrazyl (DPPH), general toxicity (Brine shrimp toxicity assay) , insecticidal ( Contact toxicity insecticidal assay) and antimalarial activities (hemebiocrystallization inhibition assay).

Behavioral and general effects of subacute oral arsenic exposure in rats with and without fluoride

Consequences of oral arsenic and fluoride exposure on motor behavior and general toxicity were modeled in young adult male rats which received sodium (meta)arsenite (10 mg/kg b.w.), sodium fluoride (5 mg/kg b.w.), and their combination by gavage, once daily, 5 days a week for 6 weeks. After 6 weeks, 6 animals per group were dissected, while the other 6 were kept for 6 more weeks untreated. Body weight, together with food and water consumption, was measured daily. Arsenic, alone or along with fluoride, caused significant decrease in rearing, and increase in immobility and local activity in the open field in the 3rd and 6th week. By the 12th week, these changes mostly diminished. Weight gain, and food and water consumption were significantly reduced by arsenic but normalized post treatment. Fluoride had no own effect and mostly no influence on effects of arsenic. Massive deposition of arsenic in the rats' blood, cerebral cortex, and liver by the 6th week, and partial elimination by the 12th week, was seen. The results underline the risk of neuro-functional damage by arsenic and call for further investigations.