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Objective. To explore the impact of genistein (Gen) on the apoptosis of neuronal cells in naturally aged rats and its mechanism. Methods. Fifty SD male rats were allocated into five groups at random, including youth group (3M group), natural aging group (24M group), and Gen low-, medium-, and high-dose groups. Starting from 18 months of age, Gen 10, 30, and 60 mg-kg-1 were administered via gavage to the Gen low-, medium-, and high-dose groups, respectively, while the rats in the natural aging group was given saline by gavage until 24 months of age, and the drug was stopped for 1 d per week for 6 months. The protein expression of target genes was examined using western blotting. Results. In contrast to the 3M group, the 24M group rats showed disturbed neuronal cell arrangement and massive cell degeneration. After 6 months of Gen intervention, in contrast to the 24M group, the neural cell pathology in the CA3 area of the hippocampus improved and cell apoptotic decreased observably. In contrast to the 3M group, the protein expression of c-Jun amino-terminal kinase (p-JNK), C/EBP homologous protein (CHOP), inflammatory vesicle 3-associated factor (NLRP3), cysteine protease-1 (Caspase-1), and apoptosis-related punctate protein (ASC) and downstream inflammatory factors in the hippocampus was obviously increased in the 24M group. In contrast to the 24M group, the protein expression of p-JNK, CHOP, NLRP3, Caspase-1, and ASC and downstream inflammatory factors in the hippocampus was observably declined in Gen groups. Conclusion. Gen has a protective effect on hippocampal neurons in aging rat brain tissue via the inhibition of the ERS apoptotic signaling pathway and NLRP3 inflammatory vesicle activation. [ABSTRACT FROM AUTHOR]

The present study aimed to characterize the glucan from C. mollissima Blume fruits and its selenium derivative, then investigate their antitumor activity in vitro. A glucan, designated as CPA, was firstly isolated from the fruits of C. mollissima Blume. Structure analysis indicated that CPA was a linear 1,6-α-D-glucan with the average molecular weight about 2.0 × 10 kDa. The selenylation modification derivative of CPA (sCPA), exhibited a stronger antiproliferative effect on tumor cells than CPA in vitro. CPA and sCPA could induce HeLa cells apoptosis and decrease mitochondrial membrane potential. sCPA could also arrest HeLa cells in S phase, promote reactive oxygen species generation and activate caspase-3 activity in HeLa cells. These results manifest that CPA and sCPA inhibit the proliferation of HeLa cells via different mechanisms, which is meaningful for their potential use as antitumor drugs. [ABSTRACT FROM AUTHOR]

Abstract A 1,6-α-D-glucan (CPA) with a high molecular weight of 2.0 × 103 kDa was isolated from the fruits of Castanea mollissima Blume. CPA showed good water solubility, low side effects on normal cells, and moderate cytotoxicity on cancer cells. Selenium nanoparticles (SeNPs) possess significant anticancer effects, but poor water solubility and dispersity. Therefore, an effective nanocomposite was designed in order to enhance the stability and anticancer effects of SeNPs decorated with CPA. Water soluble and dispersed selenium nanoparticles (CPA-SeNPs) were fabricated using CPA and Na 2 SeO 3 by redox reaction with ascorbic acid. The average diameter of CPA-SeNPs was 53.7 ± 4.0 with a Se content of approximately 171.4 mg/g. CPA-SeNPs showed a significant anti-proliferative effect on HeLa cells in vitro. Since these NPs could induce apoptosis and S phase arrest. The apoptotic pathway triggered by CPA-SeNPs on HeLa cells was also characterized as induced by reactive oxygen species (ROS) overproduction, mitochondrial dysfunction and activation of caspase-3. This study suggested that CPA-SeNPs could be developed as a potential candidate in cancer treatment, especially against human cervical cancer. Highlights • CPA-SeNPs was fabricated using CPA and Na 2 SeO 3 by reducing with ascorbic acid. • CPA-SeNPs was approximately 50 nm with a Se content about 171.4 mg/g. • CPA-SeNPs showed a significant anti-proliferative effect on HeLa cells in vitro. • CPA-SeNPs induced HeLa cells apoptosis in an intrinsic apoptosis pathway. [ABSTRACT FROM AUTHOR]

Acquired resistance to growth factor receptor tyrosine kinase inhibitors limits the therapeutic benefits gained by EGFR-mutant lung adenocarcinoma (LUAD) patients treated with gefitinib. Circular RNAs (circRNAs) are novel noncoding RNAs implicated in the regulation of chemoresistance in malignancies. However, whether circRNAs participate in the development of EGFR-TKI resistance in LUAD remains to be clarified. Here, we report that circASK1 (hsa_circ_0007798) is significantly downregulated in gefitinib-resistant cells and enhances the gefitinib sensitivity of LUAD cells. Mechanistically, we identified a novel protein encoded by circASK1, ASK1-272a.a, which is essential for ASK1/JNK/p38 signaling activation and mediates the chemosensitivity-inducing effect of circASK1 in LUAD. Importantly, this novel isoform competes with ASK1 for binding to Akt1, therefore antagonizing Akt1-induced ASK1 phosphorylation and inactivation, leading to the activation of ASK1-induced apoptosis and alleviating gefitinib resistance. Moreover, increased YTHDF2-mediated endoribonucleolytic cleavage of m6A-modified circASK1 accounts for its downregulation in gefitinib-resistant cells. The clinical data and in vivo model further corroborated the suppressive effect of circASK1 and its encoded protein on gefitinib resistance. Our study provides a novel therapeutic target to overcome gefitinib resistance in LUAD patients. [ABSTRACT FROM AUTHOR]

Based on the synthesis of curcumin and its derivatives from aromatic aldehydes, a novel series of palladium(II) complexes with curcumin (or its derivatives) and 2,2′-bipyridine have been synthesized through a directed self-assembly approach that involves spontaneous deprotonation of the curcuminoid ligands in H 2 O/acetone solution. These complexes have been characterized by 1 H ( 13 C) NMR, HRMS and elemental analysis. Crystal structure of 3h has been determined by X-ray diffraction analysis. Their cytotoxicity was tested by MTT. The preliminary results showed that complexes 3d , 3f , 3h have significant inhibition on proliferation of three carcinoma cells such as MCF-7, HeLa and A549 cells, which were more active than cisplatin. Further mechanistic studies indicated that the tested complex 3h arrested the cell cycle in the S phase and can disrupted mitochondrial membrane potential and induced tumor cell apoptosis through reactive oxygen species (ROS)-dependent pathway. [ABSTRACT FROM AUTHOR]

Thirteen novel palladium(II) complexes of the general formula [Pd(bipy)(O , O ′-dkt)](PF 6), (where bipy is 2,2′-bipyridine and O , O ′-dkt is β-diketonate ligand hispolon or its derivative) have been prepared through a metal-ligand coordination method that involves spontaneous formation of the corresponding diketonate scaffold. The obtained palladium(II) complexes have been characterized by NMR spectroscopy, ESI-mass spectrometry as well as elemental analysis. The cytotoxicity analysis indicates that most of the obtained palladium(II) complexes show promising growth inhibition in three human cancer cell lines. Flow cytometry analysis shows complex 3e could promote intracellular reactive oxygen species (ROS) accumulation and lead cancer cell death. And the suppression of ROS accumulation and the rescue of cell viability in HeLa cells by N -acetyl-L-cysteine (NAC) suggest the possible link between the increase in ROS generation and cytotoxicity of complex 3e. Flow cytometry analysis also reveal that complex 3e cause cell cycle arrest in the G2/M phase and collapse of the mitochondrial membrane potential, promote the generation of ROS and lead to tumor cell apoptosis. The interactions of complex 3e with calf thymus DNA (CT-DNA) have been evaluated by UV–Vis spectroscopy, fluorescence quenching experiments and viscosity measurements, which reveal that the complex interact with CT-DNA through minor groove binding and/or electrostatic interactions. Further, the results of fluorescence titration and site marker competitive experiment on bovine serum albumin (BSA) suggest that complex 3e can quench the fluorescence of BSA via a static quenching process and bind to BSA in Sudlow's site II. Thirteen palladium (II) complexes of hispolon derivatives were synthesized. Most of them possess promising growth inhibition activities. Mechanistic studies indicate that complex 3e cause cell cycle arrest in the G2/M phase, reactive oxygen species (ROS) accumulation and cell apoptosis. Its interactions with DNA/BSA (bovine serum albumin) have also been studied. Unlabelled Image • A novel series of palladium (II) complexes of hispolon derivatives was obtained. • Most complexes were found to be more toxic against HeLa than MCF-7 and MGC803 cells. • Complex 3e inhibits HeLa cells proliferation via apoptosis induction and cell cycle arrest. • Minor groove binding and/or electrostatic interactions of complex 3e with DNA were found. • Complex 3e exhibits moderate binding affinity toward BSA (bovine serum albumin). [ABSTRACT FROM AUTHOR]