Morin encapsulated chitosan nanoparticles (MCNPs) ameliorate arsenic induced liver damage through improvement of the antioxidant system and prevention of apoptosis and inflammation in mice

Chronic exposure to arsenic over a period of time induces toxicity, primarily in the liver but gradually in all systems of the body. Morin hydrate (MH; 2',3,4',5,7-pentahydroxyflavone), a potent flavonoid abundantly present in plants of the Moraceae family, is thought to be a major bioactive compound that may be used to prevent a wide range of disease pathologies including hepatotoxicity. Therapeutic applications of morin (MOR) are however seriously constrained because of its insolubility, poor bioavailability, high metabolism and rapid elimination from the human body. Nanoformulation of MOR is a possible solution to these problems. In the present study we investigated the effectiveness of morin encapsulated chitosan nanoparticles (MCNPs) against arsenic induced liver damage in mice. MNCPs with an average diameter of 124.5 nm, a zeta potential of +16.2 mV and an encapsulation efficiency of 78% were prepared. Co-treatment of MOR and MCNPs by oral gavage on alternate days reduced the serum levels of AST, ALT, and ALP that were elevated in arsenic treated mice. The efficiency of MCNPs was found to be nearly 4 times higher than that of free MOR. Haematological and serum biochemical parameters including lipid profiles altered by arsenic were normalized following MCNP treatment. Arsenic deposition was lowered in the presence of MCNPs. Administration of MCNPs markedly inhibited ROS generation and elevated MDA levels in arsenic exposed mice. The level of hepatic antioxidant factors such as nuclear Nrf2 (Nrf2), superoxide dismutase (SOD), catalase (CAT), glutathione (GSH), GSH peroxidase (GPx), glutathione-S-transferase (GST), heme oxygenase-1 (HO-1), and NADPH quinone oxidoreductase 1(NQO1) were markedly enhanced in the arsenic + MCNP group. Treatment by MCNPs prevented the arsenic induced damage of tissue histology. Also, MCNPs suppressed the arsenic induced pro- and anti-apoptotic parameters and attenuated the level of inflammatory mediators. Our data suggest that MCNPs are good hepatoprotective agents compared to free morin against arsenic induced toxicity and the protective effect results from its strong antioxidant, antiapoptotic and anti-inflammatory properties.

Sertaconazole provokes proapoptotic autophagy via stabilizing TRADD in nonsmall cell lung cancer cells

Nonsmall cell lung cancer (NSCLC) is one of the most commonly diagnosed and lethal cancers characterized by relatively low overall cure and poor survival rates with great challenge for consistent effective clinical treatment. Here we demonstrated that the antifungal sertaconazole displays potent anti-NSCLC effect by promoting apoptosis in vitro and in vivo. Further studies found that sertaconazole induces complete autophagic flux, which contributes to sertaconazole-induced apoptosis and subsequent growth suppression in NSCLC cells. Further studies demonstrated that sertaconazole provokes TNF receptor type 1 associated death domain protein (TRADD) expression via stabilizing it from ubiquitination-mediated degradation, which results in Akt dephosphorylation and thereby triggers proapoptotic autophagy in NSCLC cells. Moreover, we found that TRADD suppression reverses sertaconazole-induced proapoptotic autophagy and relieves growth suppression, indicating the vital role of TRADD-regulated proapoptotic autophagy in the anti-NSCLC activity of sertaconazole. In summary, our findings suggest that sertaconazole could be a highly promising anti-NSCLC drug by triggering proapoptotic autophagy via stabilizing TRADD, which may provide a new potential therapeutic option for patients with NSCLC.

Curcumin stably interacts with DNA hairpin through minor groove binding and demonstrates enhanced cytotoxicity in combination with FdU nucleotides

We report, based on biophysical studies and molecular mechanical calculations that curcumin binds DNA hairpin in the minor groove adjacent to the loop region forming a stable complex. UV-Vis and fluorescence spectroscopy indicated interaction of curcumin with DNA hairpin. In this novel binding motif, two ɣ H of curcumin heptadiene chain are closely positioned to the A₁₆-H8 and A₁₇-H8, while G₁₂-H8 is located in the close proximity of curcumin α H. Molecular dynamics (MD) simulations suggest, the complex is stabilized by noncovalent forces including; π-π stacking, H-bonding and hydrophobic interactions. Nuclear magnetic resonance (NMR) spectroscopy in combination with molecular dynamics simulations indicated curcumin is bound in the minor groove, while circular dichroism (CD) spectra suggested minute enhancement in base stacking and a little change in DNA helicity, without significant conformational change of DNA hairpin structure. The DNA:curcumin complex formed with FdU nucleotides rather than Thymidine, demonstrated enhanced cytotoxicity towards oral cancer cells relative to the only FdU substituted hairpin. Fluorescence co-localization demonstrated stability of the complex in biologically relevant conditions, including its cellular uptake. Acridine orange/EtBr staining further confirmed the enhanced cytotoxic effects of the complex, suggesting apoptosis as mode of cell death. Thus, curcumin can be noncovalently complexed to small DNA hairpin for cellular delivery and the complex showed increased cytotoxicity in combination with FdU nucleotides, demonstrating its potential for advanced cancer therapy.

Synthesis of gold(iii) ← gold(i)–NHC through disproportionation: the role of gold(i)–NHC in the induction of apoptosis in HepG2 cells

The anticancer activities of novel Au(i) and Au(iii)–NHC complexes based on 2-[(6-methylpyridin-2-yl)]imidazo[1,5-a]pyridin-4-ylium hexafluorophosphate have been investigated.

Intercellular network structure and regulatory motifs in the human hematopoietic system

The hematopoietic system is a distributed tissue that consists of functionally distinct cell types continuously produced through hematopoietic stem cell (HSC) differentiation. Combining genomic and phenotypic data with high-content experiments, we have built a directional cell-cell communication network between 12 cell types isolated from human umbilical cord blood. Network structure analysis revealed that ligand production is cell type dependent, whereas ligand binding is promiscuous. Consequently, additional control strategies such as cell frequency modulation and compartmentalization were needed to achieve specificity in HSC fate regulation. Incorporating the in vitro effects (quiescence, self-renewal, proliferation, or differentiation) of 27 HSC binding ligands into the topology of the cell-cell communication network allowed coding of cell type-dependent feedback regulation of HSC fate. Pathway enrichment analysis identified intracellular regulatory motifs enriched in these cell type- and ligand-coupled responses. This study uncovers cellular mechanisms of hematopoietic cell feedback in HSC fate regulation, provides insight into the design principles of the human hematopoietic system, and serves as a foundation for the analysis of intercellular regulation in multicellular systems.

Gold (I) N-heterocyclic carbene complex inhibits mouse melanoma growth by p53 upregulation

BACKGROUND

Cancer treatment using gold (I) complexes is becoming popular. In this study, a gold (I) N-heterocyclic complex designated as complex 3 was synthesized, its cytotoxicity was examined, and its anti-melanoma activity was evaluated in vitro and in vivo.

METHODS

Viability of cancer cells was determined by MTT assay upon treatment with various concentrations of a gold (I) N-heterocyclic carbene complex (complex 3) in a dose and time dependent manner. Mouse melanoma cells B16F10 were selected for further apoptotic studies, including flowcytometric analysis of annexin binding, cell cycle arrest, intracellular ROS generation and loss in the mitochondrial membrane potential. ELISA based assays were done for caspase activities and western blots for determining the expression of various survival and apoptotic proteins. Immunocytology was performed to visualize the translocation of p53 to the nucleus. B16F10 cells were inoculated into mice and post tumor formation, complex 3 was administered. Immunohistology was performed to determine the expressions of p53, p21, NF-κB (p65 and p50), MMP-9 and VEGF. Student's t test was used for determining statistical significance. The survival rate data were analyzed by Kaplan-Meier plots.

RESULTS

Complex 3 markedly inhibited the growth of HCT 116, HepG2, and A549, and induced apoptosis in B16F10 cells with nuclear condensation, DNA fragmentation, externalization of phosphatidylserine, activation of caspase 3 and caspase 9, PARP cleavage, downregulation of Bcl-2, upregulation of Bax, cytosolic cytochrome c elevation, ROS generation, and mitochondrial membrane potential loss indicating the involvement of an intrinsic mitochondrial death pathway. Further, upregulation of p53, p-p53 (ser 15) and p21 indicated the role of p53 in complex 3 mediated apoptosis. The complex reduced tumor size, and caused upregulation of p53 and p21 along with downregulation of NF-κB (p65 and p50), VEGF and MMP-9. These results suggest that it induced anti-melanoma effect in vitro and in vivo by modulating p53 and other apoptotic factors.

CONCLUSIONS

The gold (I) N-heterocyclic carbene complex (C22H26N6AuO2PF6) designated as complex 3 induced ROS and p53 dependent apoptosis in B16F10 cells involving the mitochondrial death pathway along with suppression of melanoma tumor growth by regulating the levels of pro and anti apoptotic factors (p53, p21, NF-κB, VEGF and MMP-9).

N-heterocyclic carbene supported Au(i) and Au(iii) complexes: a comparison of cytotoxicities

Au(i)–NHC (3) is more potent than Au(iii)–NHC (4) and cisplatin against the four cancer cell lines.

Cytotoxicity of silver(i), gold(i) and gold(iii) complexes of a pyridine wingtip substituted annelated N-heterocyclic carbene

Cl–Ag(i)–NHC, Cl–Au(i)–NHC, and Cl₃–Au(i)–NHC complexes based on the 1-methyl-2-pyridin-2-yl-2H-imidazo[1,5-a]pyridin-4-ylium chloride, were tested for their cytotoxicity towards different cancer cell lines.

Research Progress on Natural Triterpenoid Saponins in the Chemoprevention and Chemotherapy of Cancer

Triterpenoid saponins are glycosides with remarkable structural and bioactive diversity. They are becoming increasingly significant in the treatment of cancer due to their efficacy and safety. This chapter provides an update on the sources, pharmacological effects, structure-activity relationships, and clinical studies of anticancer triterpenoid saponins with a particular focus on the molecular mechanisms underlying their therapeutic properties. The correlative references and study reports described were collected through PubMed. The anticancer triterpenoid saponins enable the inhibition of cancer formation and progression by modulating multiple signaling targets related to cellular proliferation, apoptosis, autophagy, metastasis, angiogenesis, inflammation, oxidative stress, multidrug resistance, cancer stem cells, and microRNAs. This review provides new insights into the molecular basis of triterpenoid saponins in the chemoprevention and chemotherapy of cancer.

Effect of corchorusin-D, a saikosaponin like compound, on B16F10 melanoma cells (in vitro and in vivo)

Corchorusin-D (COR-D), isolated from Corchorus acutangulus, was reported to induce apoptosis in leukemic cells. However, no studies concerning its activity on melanoma cells have been reported. We have evaluated its in vitro anti-cancer activity on melanoma cells (B16F10, SK-MEL-28, and A375). The results demonstrate that COR-D showed maximum inhibition of B16F10 cells in vitro. COR-D induced mitochondrial dysfunction and altered the Bax/Bcl-2 ratio with down regulation of pro-caspases 9 and activation of caspase 3 in B16F10 cells, triggering intrinsic pathway of apoptosis. Moreover, it inhibited the in vivo B16F10 tumor growth and increased the survival rate of mice. Greater number of Annexin V-FITC and propidium iodide (PI)-positive tumor cells signified that COR-D induced apoptosis in vivo also. The reduction in tumor growth is well correlated with decreased microvascular density of the tumor cells in treated mice. In conclusion, this study reveals that COR-D-induced mitochondrial dysfunction is responsible for the induction of apoptotic cell death.