Evaluation of Oxidative Stress Status in Familial Hypercholesterolemia.

BACKGROUND: Familial hypercholesterolemia (FH) is an autosomal dominant genetic disorder characterizied by elevated levels of circulating low-density lipoprotein cholesterol (LDL-C) which is an important source of substrates to be oxidized by different oxidative agents. Subsequently, the oxidized LDLs (oxLDLs) induce further oxidative reactions in FH patients, which contributes to the development of atherosclerosis and advanced cardiovascular events in these patients. This study aimed to investigate the association of oxidant/antioxidant markers with FH. METHODS: This case-control study comprised 18 HoFH, 18 HeFH, and 20 healthy subjects. Oxidant/antioxidant markers including MDA, MPO, thiol, nitric oxide (NO), myeloperoxidase (MPO), glutathione peroxidase (GPx), SOD, and CAT were assessed by colorimetric methods. Prooxidant-antioxidant balance was also measured by pro-oxidant antioxidant balance (PAB) assay. RESULTS: The levels of MDA (p < 0.001), MPO activity (p < 0.001), thiol (p < 0.001), NO (p < 0.01), and PAB (p < 0.001) were notably higher in HoFH group in comparison with healthy subjects. HeFH group also showed significantly higher levels of thiol (p < 0.001) and PAB (p < 0.001) when compared to healthy subjects. Elevated levels of MDA (p < 0.001) and PAB (p < 0.001) were also observed in HoFH relative to HeFH. No significant differences were found between the studied groups in the case of antioxidant enzyme activities. The results of binary logistic regression showed that PAB (OR: 0.979; p = 0.033), and MDA (OR: 0.996; p = 0.018) levels were inversely associated with HoFH, although, after adjustment for age and LDL-C levels, these associations were diminished. CONCLUSION: Several oxidant/antioxidant differences were found between FH patients and healthy individuals as well as between HoFH and HeFH patients. These differences might be strongly dependent on plasma LDL-C levels.

Dendrosomal nanocurcumin and exogenous p53 can act synergistically to elicit anticancer effects on breast cancer cells.

Triple-negative breast cancer (TNBC) constitutes an important histological subtype of breast cancer with a highly metastatic phenotype. The aim of the current study was to investigate the possible synergism between dendrosomal nanocurcumin (DNC) and exogenously delivered p53 in producing anticancer effects on a TNBC cell line. MTT assay was exploited to determine the viability of MDA-MB-231 cells against DNC and measure the impact of p53 overexpresssion on DNC-related cytotoxicity. Annexin-V/PI staining followed by flow cytometry and wound healing assay were used to evaluate the effects of DNC and exogenous p53, alone and in combination, on apoptosis induction and migratory capacity of MDA-MB-231 cells, respectively. Also, quantitative real-time PCR was applied to analyze the transcript levels of EMT- and metastasis-associated genes. Cell viability measurements demonstrated that DNC suppresses the proliferation of MDA-MB-231 cells in a time- and dose-dependent mode and exogenous p53 elevates the sensitivity of cells to DNC-mediated cytotoxic effects. Apoptosis and wound healing assays indicated that combination treatment with DNC and exogenous p53 leads to significantly increased apoptosis and decreased migration of breast cancer cells, compared with single treatment. The results of gene expression analysis highlighted the high potency of combination strategy to significantly reduce the expression of ZEB1 and BMI1 transcript levels. Altogether, our findings reveal that DNC and exogenous p53 act in a synergistic manner to elicit anticancer effects on MDA-MB-231 breast cancer cells. Therefore, our combination approach might be considered as a promising strategy for the development of new therapeutic modalities against breast cancer.

Biased selection of propagation-related TUPs from phage display peptide libraries.

Phage display is rapidly advancing as a screening strategy in drug discovery and drug delivery. Phage-encoded combinatorial peptide libraries can be screened through the affinity selection procedure of biopanning to find pharmaceutically relevant cell-specific ligands. However, the unwanted enrichment of target-unrelated peptides (TUPs) with no true affinity for the target presents an important barrier to the successful screening of phage display libraries. Propagation-related TUPs (Pr-TUPs) are an emerging but less-studied category of phage display-derived false-positive hits that are displayed on the surface of clones with faster propagation rates. Despite long regarded as an unbiased selection system, accumulating evidence suggests that biopanning may create biological bias toward selection of phage clones with certain displayed peptides. This bias can be dependent on or independent of the displayed sequence and may act as a major driving force for the isolation of fast-growing clones. Sequence-dependent bias is reflected by censorship or over-representation of some amino acids in the displayed peptide and sequence-independent bias is derived from either point mutations or rare recombination events occurring in the phage genome. It is of utmost interest to clean biopanning data by identifying and removing Pr-TUPs. Experimental and bioinformatic approaches can be exploited for Pr-TUP discovery. With no doubt, obtaining deeper insight into how Pr-TUPs emerge during biopanning and how they could be detected provides a basis for using cell-targeting peptides isolated from phage display screening in the development of disease-specific diagnostic and therapeutic platforms.

Dendrosomal nanocurcumin and p53 overexpression synergistically trigger apoptosis in glioblastoma cells.

OBJECTIVES: Glioblastoma is the most lethal tumor of the central nervous system. Here, we aimed to evaluate the effects of exogenous delivery of p53 and a nanoformulation of curcumin called dendrosomal curcumin (DNC), alone and in combination, on glioblastoma tumor cells. MATERIALS AND METHODS: MTT assay was exploited to measure the viability of U87-MG cells against DNC treatment. Cells were separately subjected to DNC treatment and transfected with p53-containing vector and then were co-exposed to DNC and p53 overexpression[A GA1][B2]. Annexin-V-FLUOS staining followed by flow cytometry and real-time PCR were applied to examine apoptosis and analyze the expression levels of the genes involved in cell cycle and oncogenesis, respectively. RESULTS: The results of cell viability assay through MTT indicated that DNC inhibits the proliferation of U87-MG cells in a time- and dose-dependent manner. Apoptosis evaluation revealed that p53 overexpression accompanied by DNC treatment can act in a synergistic manner to significantly enhance the number of apoptotic cells (90%) compared with their application alone (15% and 38% for p53 overexpression and DNC, respectively). Also, real-time PCR data showed that the concomitant exposure of cells to both DNC and p53 overexpression leads to an enhanced expression of GADD45 and a reduced expression of NF-κB and c-Myc. CONCLUSION: The findings of the current study suggest that our combination strategy, which merges two detached gene (p53) and drug (curcumin) delivery systems into an integrated platform, may represent huge potential as a novel and efficient modality for glioblastoma treatment.