Dermal thirdhand smoke exposure induced epidermal alterations in human keratinocyte cells through oxidative damage and MMP-1 expression.

Thirdhand smoke (THS) is the residual cigarette smoke that settles on indoor surface fabrics, dust and can accumulate in the environment. Therefore, it can be a risk factor for individuals who have frequent dermal contact with THS-contaminated surfaces. In the present study, it was aimed to elucidate the toxicity of dermal THS exposure in HaCaT human keratinocytes. The THS was extracted from terrycloth exposed to 3R4F research cigarette smoke in a closed chamber and the adverse outcomes induced by THS were determined through assessment of cytotoxicity tests (MTT and NRU), intracellular GSH level, total SOD activity, matrix metalloproteinase-1 (MMP-1) and IL-6 levels. The wound healing capacity of THS-exposed keratinocytes was evaluated via scratch assay. A potent antioxidant isothiocyanate compound, sulforaphane (SFN), was used as a negative control. THS was dose-dependently cytotoxic (12.5%-100%, v/v) to the HaCaT cells through mitochondrial cell dysfunction (p < 0.01), which was ameliorated by SFN (0.62 µM) pre-treatment. In parallel, THS exposure significantly decreased the intracellular GSH deposits and T-SOD activity in keratinocytes. Collagen degradation through elevated MMP-1 expression was observed in THS-exposed cells in parallel with the delay of wound healing and increased pro-inflammatory response in a dose-dependent manner (p < 0.05). The findings are expected to raise awareness about THS as an environmental pollutant for skin, particularly in the highest-ranked countries in cigarette consumption. To conclude, these results might contribute to the studies on the importance of dermal exposure to THS in the pathogenesis of epidermal alterations and the other skin diseases.

Alpha-Lipoic Acid Modulates the Oxidative and Inflammatory Responses Induced by Traditional and Novel Tobacco Products in Human Liver Epithelial Cells.

Smoking has been associated with NAFLD recently, thus might be a contributing factor for liver disease progression. In this study, we identified the modulative action of α-lipoic acid (α-LA), an organosulphur compound, towards heated tobacco product (HTP) and cigarette smoke extract (CSE)-induced oxidative stress and inflammation in human liver HepG2 cells. The cells were pre-treated with α-LA and exposed to tobacco extracts, and cytotoxicity, oxidative response (SOD, CAT activities and GSH, MDA levels), inflammation (nitrite, IL-6, AhR levels), and liver function (AST/ALT) were assessed. According to the results, a notable increase in oxidative response was observed with CSE, whereas GSH depletion and decreased SOD activity were the key toxicological events induced by HTP (p<0.05). The oxidative and inflammatory responses were ameliorated with α-LA treatment, particularly through GSH restoration and IL-6 modulation. To conclude, these findings on α-LA might contribute to the design of novel adjuvant therapies for people exposed to tobacco smoke.

Synthesis, Molecular Docking and Anticancer Activity of Diflunisal Derivatives as Cyclooxygenase Enzyme Inhibitors.

Cyclooxygenase enzymes play a vital role in inflammatory pathways in the human body. Apart from their relation with inflammation, the additional involvement of COX-2 enzyme with cancer activity was recently discovered. In some cancer types the level of COX-2 enzyme is increased indicating that this enzyme could be a suitable target for cancer therapy. Based on these findings, we have synthesized some new diflunisal thiosemicarbazides and 1,2,4-triazoles and tested them against androgen-independent prostate adenocarcinoma (PC-3), colon carcinoma (HCT-116), human breast cancer (T47D), breast carcinoma (MCF7) and human embryonic kidney (HEK-293) cell lines. Specifically, the diflunisal and thiosemicarbazide functionality are combined during the synthesis of original compounds anticipating a potency enhancement. Compounds 6, 10, 15 and 16 did not show cytotoxic effects for the HEK293 cell line. Among them, compounds 15 and 16 demonstrated anticancer activity for the breast cancer cell line T47D, whereas compounds 6 and 10 which are thiosemicarbazide derivatives displayed anti-tumourigenic activity against the PC-3 cell line, consistent with the literature. However, no activity was observed for the HCT-116 cancer cell line with the tested thiosemicarbazide derivatives. Only compound 16 displayed activity against the HCT-116 cell line. Therefore, it was speculated that the diflunisal and thiosemicarbazide functionalities potentiate anticancer activity on prostate cancer and the thiosemicarbazide functionality decreases the anticancer activity of diflunisal on colon cancer cell lines. In order to gain insight into the anticancer activity and COX-2 inhibition, molecular docking studies were carried out for COX-1 and COX-2 enzymes utilizing the newly synthesized compounds 15, and 16. Both 15 and 16 showed high selectivity and affinity toward COX-2 isozyme over COX-1, which is in agreement with the experimental results.

Discovery of Novel Thiophene/Hydrazones: In Vitro and In Silico Studies against Pancreatic Cancer.

Cancer is the disease with the highest mortality. Drug studies contribute to promising treatments; however there is an urgent need for selective drug candidates. Pancreatic cancer is difficult to treat and the cancer progresses rapidly. Unfortunately, current treatments are ineffective. In this study, ten new diarylthiophene-2-carbohydrazide derivatives were synthesized and evaluated for their pharmacological activity. The 2D and 3D anticancer activity studies suggested the compounds 7a, 7d, and 7f were promising. Among these, 7f (4.86 µM) showed the best 2D inhibitory activity against PaCa-2 cells. Compounds 7a, 7d and 7f were also tested for their cytotoxic effects on healthy cell line but only compound 7d showed selectivity. Compounds 7a, 7d, and 7f showed the best 3D cell line inhibitory effect according to spheroid diameters. The compounds were screened for their COX-2 and 5-LOX inhibitory activity. For COX-2, the best IC50 value was observed for 7c (10.13 µM) and all compounds showed significantly lower inhibition compared to standard. In the 5-LOX inhibition study, compounds 7a (3.78 µM), 7c (2.60 µM), 7e (3.3 µM), and 7f (2.94 µM) demonstrated influential activity compared to standard. Regarding molecular docking studies, binding mode of compounds 7c, 7e, and 7f to the 5-LOX enzyme were non-redox or redox types, but not the iron-binding type. As dual inhibitors of 5-LOX and pancreatic cancer cell line, 7a and 7f were identified as the most promising compounds.

PEG4000 modified liposomes enhance the solubility of quercetin and improve the liposome functionality: in vitro characterization and the cellular efficacy.

Quercetin, a multifunctional therapeutic agent, is used in various types of cancer. However, its therapeutic effect is limited by virtue of poorly aqueous solubility and instability in the physiological medium. To overcome these limitations, we aimed (i) to design quercetin loaded liposomes with unlinked-PEG4000 with regard to not only surface modification but also solubility enhancement, and (ii) to investigate the antineoplastic effects on HeLa cells. PEG4000 increased the quercetin solubility 2.2 fold. PEG4000 modified liposomes displayed small particle size (254 ± 69 nm), low polydispersity index (0.236 ± 0.018), favorable zeta potential (-35.4 ± 0.6 mV), high quercetin encapsulation efficiency (87.6 ± 5.6%), and drug loading (22.2 ± 6.9%). The homogeneity and particle size of stable PEGylated liposomes were proved by transmission electron microscopy. The drug release was reached up to 65.1 ± 3.8% in 6 h. The IC50 value of quercetin loaded PEGylated liposomes was 16.3 µg/mL on HeLa cells, while that of quercetin was 88.3 µg/mL. PEGylated liposomes remarkably hampered the adherence and colony formation ability of cells according to crystal violet staining tests. The convenience of PEGylated liposomes for the parenteral application was stated by the hemolysis assay. The high-throughput screening assays based on AO/PI staining proved the drastic decrease of viable cell count. Moreover, qPCR tests based on gene expression levels revealed that the quercetin loaded PEGylated liposomes treatment could be more effective than free quercetin on the mitochondrial apoptosis of HeLa cells. These promising results allow considering further in vivo studies for efficient cancer treatment with quercetin loaded PEG4000 modified liposomes.

Long chain fatty acids can form aggregates and affect the membrane integrity.

Stearic acid (SA) and oleic acid (OA) which are inherently existing fatty acids (FAs) in the body can alter cell membrane function and interact with each other. However, discrepancies arise as to whether these effects are beneficial or harmful on the body. To resolve this ambiguity, there is a dire need to study how FAs can affect the etiology of diseases and their treatment. In this study, we aimed to investigate long chain FAs aggregation behaviors and their effects on membrane integrity and cell viability. We determined the critical aggregation concentration (CAC) of SA and OA (1110 µM and 300 µM, respectively which were less amount than that used in nanocarriers). In TEM images, hexagonal overlapped or fused structures of SA were seen, whereas quite small spherical clusters of OA were obtained. Membrane integrity assessments demonstrated that SA and OA at their own CAC and below could crack the lipid junctions on membrane mimicking systems. Moreover, they completely disrupt the membrane integrity above the CAC at pH 7.2. Cell viabilities on various cell lines were assessed after exposed to SA or OA aggregates. SA was more aggressive than OA on cell death in all cell lines. The effect of SA on PC3 cell lines was in a concentration-dependent manner. The effect of SA above CAC boosted the inhibition of cell viability. Furthermore, OA showed a proliferation effect on PC3 cells. Consequently, the aggregation behavior of FAs should be considered as a noteworthy factor in physiological functions.