Triton X-100 induces apoptosis in human hepatoma cell lines

Investigation of quinolone-tethered aminoguanidine as novel antibacterial agents

A recent study identified quinolone-based thiosemicarbazone with an MIC₉₀ value of 2 µM against Mycobacterium tuberculosis (Mtb). Herein, we report further optimization of the previous hit, which led to the discovery of quinolone-tethered aminoguanidine molecules with generally good antitubercular activity. Compounds 7f and 8e emerged as the hits of the series with submicromolar antitubercular activity, exhibiting MIC₉₀ values of 0.49/0.90 and 0.49/0.60 µM, respectively, in the 7H9 CAS GLU Tx medium. This shows a fivefold increase in antitubercular activity compared to the previous study. Target compounds were also screened against ESKAPE (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter species) pathogens. However, the series generally exhibited poor antibacterial activities, with only compounds 8d and 8e demonstrating >50% growth inhibition of Staphylococcus aureus and Pseudomonas aeruginosa at 32 µg/ml. The compounds displayed selective antitubercular activity as they showed no cytotoxicity effects against two noncancerous human cell lines. In silico studies predict 7f to have good solubility, no inhibitory effect on cytochrome P450 isoenzymes, and to be a non-pan-assay interfering compound.

Exploration of 4-aminopyrrolo[2,3-d]pyrimidine as antitubercular agents

Tuberculosis (TB) is one of the leading causes of death worldwide. Developing new anti-TB compounds using cost-effective processes is critical to reduce TB incidence and accomplish the End TB Strategy milestone. Herein, we describe the synthesis and structure–activity relationships of a library of thirty 7H-Pyrrolo[2,3-d]pyrimidine derivatives providing insights into the contributions of different aromatic, aryl and alkyl substitution at the C-4 position of the 7-deazapurine ring. The minimum inhibitory concentration (MIC) of the compounds against the green fluorescent protein (GFP) reporter strain of Mycobacterium tuberculosis was assayed using the standard broth microdilution method, and cell toxicity was determined using the MTT assay. Sixteen compounds displayed in vitro activity against the GFP reporter strain of Mycobacterium tuberculosis with MIC₉₀ values of 0.488–62.5 µM. This study highlights the most potent derivative, N-(4-phenoxy phenyl)-7H-pyrrolo[2,3-d]pyrimidin-4-amine with a MIC₉₀ value of 0.488 µM and was non-cytotoxic to the Vero cell line. Moreover, all the potent compounds from this series have a ClogP value less than 4 and molecular weight < 400; thus, likely to maintain drug-likeness during lead optimisation.

Synthesis and in vitro antitrypanosomal evaluation of novel 6-heteroarylidene-substituted quinolone derivatives

Human African trypanosomiasis is a vector-borne tropical disease of African origin. Presently, due to human migration and climate change, the disease might present global health and economic burdens as current chemotherapy of trypanosomiasis remains a challenge due to limited existing drugs, which are of poor efficacy, cause severe adverse events and are very costly. Recently, Beteck and co-workers identified a small library of 1,3,6-substituted non-fluoroquinolones that showed moderate to weak trypanocidal activity without cytotoxic effects. The current study further explored SARs of the quinolone scaffold in search for more potent trypanocidal agents. Fifteen novel quinolone derivatives bearing a heteroarylidene moiety at positon-6 and varied chemical entities at positions -1 and -3 of the quinolone scaffold were synthesized and evaluated in vitro for antitrypanosomal activity. The compounds exhibit exceptionally good antitrypanosomal activity with IC₅₀ values in the low-micromolar to sub-micromolar range (0.08-15.26 μM), with compound 6d being the most active having an IC₅₀ value of 80 nM against T.b. brucei. Compounds in this study generally have molecular weight less than 600Da, ClogP value of 2-4 and a BBB score of 1-5, hence they could be potentially effective against both stages of trypanosomiasis.

Topography-Guided Control of Local Migratory Behaviors and Protein Expression of Cancer Cells

In vivo cancer cell migration and invasion are directed by biophysical guidance mechanisms such as pre-existing microtracks and basement membrane extracellular matrices. Here, this paper reports the correlation of the local migratory behavior of cancer cells and the biochemical signal expression using the topography that can guide or inhibit cell behaviors. To this end, the local apparent migration and the protein expression level are investigated with respect to the topographical feature size (flat, nanoline, and microline) and orientation (microline, microconcentric, and microradial) with the collectively migrating (A431) and individually migrating (MDA-MB-231 and U-87-MG) cancer cells. The results show that the migration and the protein expression of focal adhesion kinase, rho-associated protein kinase, and extracellular signal-regulated kinase are localized in the periphery of cell colony. Furthermore, the inhibition of migratory behavior at the periphery recues the protein expression, while the guidance of migration enhances the aforementioned protein expression. The results may imply the employ of biophysical inhibitory factors can help to control invasiveness of cancer cells during the progression state.

Final Report on the Safety Assessment of Octoxynol-1, Octoxynol-3, Octoxynol-5, Octoxynol- 6, Octoxynol-7, Octoxynol-8, Octoxynol-9, Octoxynol-10, Octoxynol-11, Octoxynol-12, Octoxynol-13, Octoxynol-16, Octoxynol-20, Octoxynol-25, Octoxynol-30, Octoxynol-33, Octoxynol-40, Octoxynol-70, Octoxynol-9 Carboxylic Acid, Octoxynol-20 Carboxylic Acid, Potassium Octoxynol-12 Phosphate, Sodium Octoxynol-2 Ethane Sulfonate, Sodium Octoxynol-2 Sulfate, Sodium Octoxynol-6 Sulfate, and Sodium Octoxynol-9 Sulfate1

Octoxynols are ethoxylated alkylphenols in which the size of the molecule is related to the number of moles of ethylene oxide used in synthesis. Reactions are performed at elevated temperature, under pressure, and in the presence of NaOH. It is possible that the synthesis may leave trace amounts of ethylene oxide, 1,4-dioxane, and unreacted C9 phenols. Octoxynols of various chain lengths as well as octoxynol salts and organic acids function in cosmetics either as surfactants—emulsifying agents, surfactants—cleansing agents, surfactant—solubilizing agents, or surfactants—hydrotropes in a wide variety of cosmetic products at concentrations ranging from 0.0008% to 25%, with most less than 5.0%. The octoxynols are chemically similar to nonoxynols, the safety of which were previously considered. Long-chain nonoxynols (9 and above) were considered safe as used, whereas short-chain nonoxynols (8 and below) were considered safe as used in rinse-off products and safe at concentrations less than 5% in leave-on formulations.

Neuroprotection of Grape Seed Extract and Pyridoxine against Triton-Induced Neurotoxicity

Triton WR-1339 administration causes neurotoxicity. Natural products and herbal extracts can attenuate cerebral injury. In the present study, we investigated the neuroprotective role of grape seed extract and/or vitamin B6 against triton-induced neurotoxicity. Thirty-five adult male albino rats of the Sprague-Dawley strain, weighing 140-145 g, were divided into five groups: control, triton, grape seed extract + triton, grape seed extract + triton + vitamin B6, and vitamin B6 + triton. The hematological and biochemical analyses were carried out. Alteration in iNOS mRNA gene expression was determined using reverse-transcriptase PCR analysis. In addition, qualitative DNA fragmentation was examined using agarose gel electrophoresis. Triton-treatment caused significant disturbances in the hematological parameters, the neurological functions, and the antioxidant profile. Also, triton significantly increased the iNOS mRNA expression and DNA damage. Our results showed that grape seed extract and/or vitamin B6 could attenuate all the examined parameters. These natural substances could exhibit protective effects against triton-induced neurological damage because of their antioxidative and antiapoptotic capacities.

Intima/medulla reconstruction and vascular contraction-relaxation recovery for acellular small diameter vessels prepared by hyperosmotic electrolyte solution treatment

This study aims at the evaluation of blood vessel reconstruction process of decellularized small diameter vessels prepared by a hyperosmotic electrolyte solution treatment not only histologically but also physiologically in rat transplantation model. Complete cell removal by a hyperosmotic electrolyte solution treatment was confirmed by hematoxylin/eosin staining and scanning electron microscopic observation. All acellular vessels transplanted into the rat abdominal aorta were patent up to 14 months. One week post-transplantation, the vWF-positive cells were observed on the luminal surface but the layer formation did not complete. Five weeks following transplantation, the vWF-positive endothelial cells were located on the intima consistent with intact endothelial cells. Beneath the endothelial cells, α-SMA-positive smooth muscle cells were distributed. The harvested vessels displayed formation of tunica intima (endothelial cells) and tunica medulla (smooth muscle cell) layers. We also examined the physiological properties of the vessels 12 months post-transplantation using a wire myograph system. The transplanted vessels contracted upon addition of norepinephrine and relaxed upon addition of sodium nitroprusside as well as the native vessels. In conclusion, the acellular vessels prepared with hyperosmotic electrolytic solution showed excellent and long-term patency, which may be related to the successful preservation of vascular ECM. In addition, the acellular vessels revealed the intima/medulla regeneration with the physiological contraction-relaxation functions in response to the each substance.

Polyethylene glycol induces apoptosis in HT-29 cells: potential mechanism for chemoprevention of colon cancer

Recent experimental evidence suggests that polyethylene glycol (PEG) is a highly effective chemopreventive agent against colon cancer; however, the mechanism(s) remain largely unexplored. To further elucidate this issue, we evaluated the effect of PEG on two human colon cancer cell lines. PEG treatment resulted in a dose- and time-dependent reduction in cell number without alteration in markers of cell proliferation. However, there was a dramatic and specific, concentration-dependent induction of apoptosis, with 50 mM PEG rendering approximately half the cells apoptotic. This corresponded with a 17-fold induction in the expression of the pro-apoptotic protein, prostate apoptosis response-4. Our data suggest that induction of apoptosis may be responsible, at least in part, for the ability of PEG to prevent experimental colon cancer.