A Characterization and Cell Toxicity Assessment of Particulate Pollutants from Road Traffic Sites in Kano State, Nigeria

Emerging African countries are characterized by explosive population growth and urbanization, which threaten environmental sustainability. This study comparatively characterized ambient aerosols and assessed cytotoxicity to facilitate improving health and environmental policy. Twenty-four air samples were collected at high and low-density traffic sites in Kano State using polysulfone and stainless steel filters attached to an automated pump. The physico-chemical properties of particulate matter were determined using scanning electron microscopy and energy dispersive X-ray analysis (SEM-EDX). In vitro, their potential toxicity was assessed using macrophages and cell fixation with staining. Results showed 51.7% of particles as PM2.5, with the highest particle concentration in mixed sites (urban and industrial). Particle classification into four groups by elemental composition and structure showed: Si, Al, and Ca 58–67%; other fibres, Fe, S, Mo, and Zn 1–17%; non-sand non-fibres 23–56%; and silicone-based fibres 2–28%. The abundant elements are: Si, Al, Ca, Ce, Ti, Fe, Cl, Pb, and Mn. The lowest viability on cytotoxicity assessment was recorded in mixed site M2. The majority of households were located within 50 m of air sampling sites. Proximity to traffic sites worsens health, as evidenced in cytotoxicity findings. We recommend improved urban planning and intensification of emissions control.

In vitro Anti-inflammatory Evaluation of 6-Thioguanine and 6-Hydroxy-2-Mercaptopurine as A Potential Treatment for Rheumatoid Arthritis

BACKGROUND: Eventhough 6-Mercaptopurine act as a major drug for rheumatoid arthritis (RA) treatment, however, its toxicity become a limitation. Therefore, this current study investigated whether 6-hydroxy-2-mercaptopurine (6H2MP) and 6-thioguanine (6TG) compounds are purine nucleoside analogues as a potential treatment of RA. The objective was to evaluate the therapeutics effects, especially the anti-inflammatory potential of 6H2MP and 6TG in the lipopolysaccharides (LPS)-induced RAW264.7 cells and phorbol myristate acetate (PMA)-induced HIG-82 cells.METHODS: Macrophage cells (RAW264.7) and rabbit synoviocytes (HIG-82) cells were induced using LPS and PMA to evaluate the anti-inflammatory potential of 6H2MP and 6TG. The cytotoxicity assessment was done by using MTT assay, while enzyme-linked immunosorbent assay (ELISA) was used to determine the anti‑inflammatory potential, including tumour necrosis factor (TNF-α), interleukins (IL-1β, and IL-6).RESULTS: Upon LPS-induced, RAW 264.7 macrophages demonstrated that 6H2MP and 6TG could suppress the production of nitric oxide (NO) in vitro. The half-maximal inhibitory concentration (IC50) value of 6TG and 6H2MP were 10.73 and 13.31, respectively. Further studied in PMA-induced HIG-82 synovial fibroblast cells showed that 6H2MP and 6TG also suppressed the release of NO, Prostaglandin E2 (PGE2), and inflammatory cytokines such as TNF-α, IL-1β and IL-6. The 6TG is more effective to reduce inflammatory reactions compared to 6H2MP, by the lower dose needed compared to 6H2MP in all experiments except in PGE2.CONCLUSION: The inhibition of inflammatory mediators is an important mechanism by which 6TG and 6H2MP may alleviate pain and articular inflammation. These results indicated that 6H2MP and 6TG are effective candidates for ameliorating inflammatory-associated complications.KEYWORDS: anti-inflammatory, HIG-82 cells, RAW264.7 cells, 6-Thioguanine, 6-Hydroxy-2-Mercaptopurine

Effects of Adper™ Scotchbond™ 1 XT, Clearfil™ SE Bond 2 and Scotchbond™ Universal in Odontoblasts

This study aimed to assess the cytotoxicity of commercially available adhesive strategies—etch-and-rinse (Adper™ Scotchbond™ 1 XT, 3M ESPE, St. Paul, MN, USA, SB1), self-etch (Clearfil™ SE Bond 2, Kuraray Noritake Dental Inc., Tokyo, Japan, CSE), and universal (Scotchbond™ Universal, 3M Deutschland GmbH, Neuss, Germany, SBU). MDPC-23 cells were exposed to adhesives extracts in different concentrations and exposure times. To access cell metabolic activity, viability, types of cell death, and cell cycle, the MTT assay, SRB assay, double labeling with annexin V and propidium iodide, and labeling with propidium iodide/RNAse were performed, respectively. Cultures were stained with May-Grünwald Giemsa for qualitative cytotoxicity assessment. The SB1, CSE, and SBU extracts determined a significant reduction in cell metabolism and viability. This reduction was higher for prolonged exposures, even for less concentrated extracts. CSE extracts significantly reduced the cell’s metabolic activity at higher concentrations (50% and 100%) from 2 h of exposure. After 24 and 96 h, a metabolic activity reduction was verified for all adhesives, even at lower concentrations. These changes were dependent on the adhesive, its concentration, and the incubation time. Regarding cell viability, SBU extracts were the least cytotoxic, and CSE was significantly more cytotoxic than SB1 and SBU. The adhesives determined a reduction in viable cells and an increase in apoptotic, late apoptosis/necrosis, and necrotic cells. Moreover, on cultures exposed to SB1 and CSE extracts, a decrease in the cells in S and G2/M phases and an increase in the cells in G0/G1 phase was observed. Exposure to SBU led to an increase of cells in the S phase. In general, all adhesives determined cytotoxicity. CSE extracts were the most cytotoxic and were classified as having a higher degree of reactivity, leading to more significant inhibition of cell growth and destruction of the cell’s layers.

Formulation, Optimization and Evaluation of Luteolin-Loaded Topical Nanoparticulate Delivery System for the Skin Cancer

In the present study, luteolin (LT)-loaded nanosized vesicles (LT-NVs) were prepared by a solvent evaporation–hydration method using phospholipid and edge activator. The formulation was optimized using three factors at a three-level Box–Behnken design. The formulated LT-NVs were prepared using the three independent variables phospholipid (A), edge activator (B) and sonication time (C). The effect of used variables was assessed on the vesicle size (Y1) and encapsulation efficiency (Y2). The selection of optimum composition (LT-NVopt) was based on the point prediction method of the software. The prepared LT-NVopt showed the particle size of 189.92 ± 3.25 nm with an encapsulation efficiency of 92.43 ± 4.12% with PDI and zeta potential value of 0.32 and −21 mV, respectively. The formulation LT-NVopt was further converted into Carbopol 934 gel (1% w/v) to enhance skin retention. LT-NVoptG was further characterized for viscosity, spreadability, drug content, drug release, drug permeation and antioxidant, antimicrobial and cytotoxicity assessment. The evaluation result revealed optimum pH, viscosity, spreadability and good drug content. There was enhanced LT release (60.81 ± 2.87%), as well as LT permeation (128.21 ± 3.56 µg/cm2/h), which was found in comparison to the pure LT. The antioxidant and antimicrobial study results revealed significantly (p ˂ 0.05) better antioxidant potential and antimicrobial activity against the tested organisms. Finally, the samples were evaluated for cytotoxicity assessment using skin cancer cell line and results revealed a significant difference in the viability % at the tested concentration. LT-NVoptG showed a significantly lower IC50 value than the pure LT. From the study, it can be concluded that the prepared LT-NVoptG was found to be an alternative to the synthetic drug as well as conventional delivery systems.