Anticancer activity of new cationic arylthiophenes against hepatocellular carcinoma

New bithiophene derivative attenuated Alzheimer's disease induced by aluminum in a rat model via antioxidant activity and restoration of neuronal and synaptic transmission

BACKGROUND

One of the hypotheses that leads to an increased incidence of Alzheimer's disease (AD) is the accumulation of aluminum in the brain's frontal cortex. The present study aimed to evaluate the therapeutic role of a novel bithiophene derivative at two doses against AlCl3-induced AD in a rat model.

METHODOLOGY

Adult male rats were divided into six groups, 18 rats each. Group 1: naïve animals, group 2: animals received a daily oral administration of bithiophene dissolved in DMSO (1 mg/kg) for 30 days every other day, groups 3-6: animals received a daily oral administration of AlCl3 (100 mg/kg/day) for 45 consecutive days. Groups 4 and 5 received an oral administration of low or high dose of the bithiophene (0.5 or 1 mg/kg, respectively). Group 6; Animals were treated with a daily oral dose of memantine (20 mg/kg) for 30 consecutive days.

MAIN FINDINGS

Al disturbed the antioxidant milieu, elevated the lipid peroxidation, and depleted the antioxidants. It also disturbed the synaptic neurotransmission by elevating the activities of acetylcholine esterase and monoamine oxidase resulting in the depletion of dopamine and serotonin and accumulation of glutamate and norepinephrine. Al also deteriorated the expression of genes involved in apoptosis and the production of amyloid-β plaques as well as phosphorylation of tau. The new bithiophene at the low dose reversed most of the previous deleterious effects of aluminum in the cerebral cortex and was in many instances superior to the reference drug; memantine.

CONCLUSION

Taking together, the bithiophene modulated the AD etiology through antioxidant activity, prevention of neuronal and synaptic loss, and probably mitigating the formation of amyloid-β plaques and phosphorylation of tau.

Azafuramidines as potential anticancer Agents: Pro-apoptotic profile and cell cycle arrest

The current study aimed to test the antiproliferative activity of three azafuramidines (X, Y, and Z) against three different human cell lines; liver HepG2, breast MCF-7, and bone U2OS. And to explore the molecular mechanism(s) of the antiproliferative activity of these derivatives. The three new azafuramidines demonstrated a potent cytotoxicity at < 2 μM against the three cell lines investigated. The azafuramidines were highly selective with selectivity index ∼ 47 - 61 folds indicating safety to the normal cells. In the scratch assay, azafuramidines significantly reduced the percentage of wound healing indicating ability to prevent or reduce metastasis. Derivatives X and Z arrested the HepG2 cells at S and G2/M phases detected by the flow cytometry. Derivatives X, Y, and Z elevated the apoptosis of HepG2 cells by ∼ 71 %, 66 %, and 59 %, respectively. Derivatives X and Z were superior to derivative Y. The potent antiproliferative, cell cycle arrest, and pro-apoptotic efficacy of these chlorophenyl derivatives could be attributed to their ability of inducing the overexpression of p53, p21, and p27. These derivatives had the potential to act as anticancer agents and merit further investigations.

Micrococcus lylae MW407006 Pigment: Production, Optimization, Nano-Pigment Synthesis, and Biological Activities

Simple Summary

The global crisis of increased mortality rates due to the emergence of antimicrobial resistance and cancers has increased researchers’ efforts to find new, potent solutions through implementing natural products in the pharmaceutical industry. The present investigation produced echinenone (yellowish-orange pigment) from Micrococcus lylae MW407006 with potent pharmacological activities. A response surface methodology statistical design was used to optimize the biomass production, pigment concentration, and antimicrobial activity. The Spearman correlation coefficient was assessed, which indicated a strong linear relationship between biomass production, pigment concentration, and antimicrobial activity. Nano-echinenone was physically synthesized through the ball-milling technique. The synthesized nano-echinenone showed higher pharmacological activities (antimicrobial, antioxidant, and antitumor activities) in comparison with the crude pigment. The significantly high selectivity index of the synthesized nano-echinenone proved its safety and paved the way for its possible use in the pharmaceutical industry.

Abstract

Bacterial pigments (e.g., melanin and carotenoids) are considered to be among the most important secondary metabolites due to their various pharmacological activities against cancer and microbial resistance. Different pigmented bacterial strains were isolated from soil samples from El Mahmoudiyah governance and screened for their antimicrobial activity. The most promising pigment producer was identified as Micrococcus lylae MW407006; furthermore, the produced pigment was identified as echinenone (β-carotene pigment). The pigment production was optimized through a central composite statistical design to maximize the biomass production, pigment concentration, and the antimicrobial activity. It was revealed that the most significant fermentation parameters were the glucose (as a carbon source) and asparagine (as a nitrogen source) concentrations. Nano-echinenone was synthesized using the ball milling technique, characterized, and finally assessed for potential antimicrobial, antioxidant, and antitumor activities. The data revealed that the synthesized nano-echinenone had higher antimicrobial activity than the crude pigment. The cytotoxic potency of echinenone and nano-echinenone was investigated in different cell lines (normal and cancer cells). The inhibition of cell proliferation and induction of cell death was observed in Caco-2 and Hep-G2 cells. The data proved that nano-echinenone is a suitable candidate for use as a safe antimicrobial and anti-hepatocellular-carcinoma agent.

Synthesis of new thienylnicotinamidines: Proapoptotic profile and cell cycle arrest of HepG2 cells

Fourteen new thienylnicotinamidines and their analogs 5a-5k, 12, 13a, and 13b were prepared and their antiproliferative potential was evaluated against the growth of 60 cancer cell lines. The tested compounds had a strong antiproliferative efficacy against almost all cancer cell lines, with the average GI₅₀ at ~2.20 µM. The effect of the thienylnicotinamidines on the growth of normal lung fibroblast cells (WI-38) indicated that these derivatives are safe to the normal cells. The selectivity index (SI) ranges from 5.5- to 42.0-fold. The conceivable mechanisms of action of the effective compounds 5d, 5f, 5g, 5i, 5j, and 5k with high SI were investigated. Although the thienylnicotinamidines are similar in structure, they could be divided into three groups as per their effects on gene expression: The first group (5d and 5f) elevated p53 and caspase 3 expression, the second group (5g and 5i) elevated p53 expression, and the last group (5j and 5k) elevated p53 and reduced topoII expression. Many thienylnicotinamides inhibited the vascular endothelial growth factor receptor-2 (VEGFR-2) in cell lysates at concentrations comparable to or better than pazopanib. The data of caspase 3 expression were confirmed by measuring the protein level by Western blot and the activity of the cleaved active enzyme. The ability to arrest the cell cycle and induce apoptosis was confirmed by flow cytometry. Taken together, two derivatives, 5d and 5f, with a distinctive VEGFR-2 inhibitory activity and a proapoptotic and cell cycle arrest profile merit further investigations.

Enhancing the chemosensitivity of HepG2 cells towards cisplatin by organoselenium pseudopeptides

Despite all recent advances in the treatment of hepatocellular carcinoma (HCC), chemotherapy resistance still represents a major challenge in its successful clinical management. Chemo-sensitization offers an attractive strategy to counter drug resistance. Herein we report the identification of novel organoselenium-based pseudopeptides as promising highly effective chemo-sensitizers in treating HCC with cisplatin. A series of functionalized pseudopeptide- (5-9 and 17-19), peptidomimetic- (10-12 and 20-23), and tetrazole-based (13-16 and 24-27) organoselenium compounds were synthesized via isonitrile-based multicomponent reactions from two novel selenium-containing isocyanides. All compounds were evaluated for their cytotoxicity against HepG2 and the non-cytotoxic doses were used to restor the sensitivity of the cells to cisplatin. New organoselenium compounds (7, 9, 15, or 23) led to an effective chemo-sensitization of HepG2 cells towards cisplatin (up-to 27-fold). Cell cycle studies indicate that the most potent peptidomimetic diselenide 23 arrested cells at the S phase and induced apoptosis via ROS modulation.