The impact of hUC MSC-derived exosome-nanoliposome hybrids on α-synuclein fibrillation and neurotoxicity.

Amyloid aggregation of α-synuclein (αSN) protein amplifies the pathogenesis of neurodegenerative diseases (NDs) such as Parkinson's disease (PD). Consequently, blocking aggregation or redirecting self-assembly to less toxic aggregates could be therapeutic. Here, we improve brain-specific nanocarriers using a hybrid of exosomes (Ex) from human umbilical cord mesenchymal stem cells (hUC MSCs) and nanoliposomes containing baicalein (Ex-NLP-Ba) and oleuropein (Ex-NLP-Ole). The hybrids contained both lipid membranes, Ex proteins, and baicalein or oleuropein. Fluorescence resonance energy transfer analysis confirmed their proper integration. The hybrids reduced the extent of αSN fibrillation and interfered with secondary nucleation and disaggregation. They not only reduced αSN pathogenicity but also enhanced drug internalization into cells, surpassing the efficacy of NLP alone, and also crossed the blood-brain barrier in a cellular model. We conclude that Ex can be successfully extracted and efficiently merged with NLPs while retaining its original properties, demonstrating great potential as a theranostic drug delivery vehicle against NDs like PD.

Characterization of exogenous αSN response genes and their relation to Parkinson's disease using network analyses.

Despite extensive research, the molecular mechanisms underlying the toxicity of αSN in Parkinson's disease (PD) pathology are still poorly understood. To address this, we used a microarray dataset to identify genes that are induced and differentially expressed after exposure to toxic αSN aggregates, which we call exogenous αSN response (EASR) genes. Using systems biology approaches, we then determined, at multiple levels of analysis, how these EASR genes could be related to PD pathology. A key result was the identification of functional connections between EASR genes and previously identified PD-related genes by employing the proteins' interactions networks and 9 brain region-specific co-expression networks. In each brain region, co-expression modules of EASR genes were enriched for gene sets whose expression are altered by SARS-CoV-2 infection, leading to the hypothesis that EASR co-expression genes may explain the observed links between COVID-19 and PD. An examination of the expression pattern of EASR genes in different non-neurological healthy brain regions revealed that regions with lower mean expression of the upregulated EASR genes, such as substantia nigra, are more vulnerable to αSN aggregates and lose their neurological functions during PD progression. Gene Set Enrichment Analysis of healthy and PD samples from substantia nigra revealed that a specific co-expression network, "TNF-α signaling via NF-κB", is an upregulated pathway associated with the PD phenotype. Inhibitors of the "TNF-α signaling via NF-κB" pathway may, therefore, decrease the activity level of this pathway and thereby provide therapeutic benefits for PD patients. We virtually screened FDA-approved drugs against these upregulated genes (NR4A1, DUSP1, and FOS) using docking-based drug discovery and identified several promising drugs. Altogether, our study provides a better understanding of αSN toxicity mechanisms in PD and identifies potential therapeutic targets and small molecules for treatment of PD.

Insights into the inhibitory mechanism of skullcapflavone II against α-synuclein aggregation and its mediated cytotoxicity.

The dangerous self-assembled and infectious seeds of α-synuclein (αSN) play primary roles in Parkinson's disease. Accordingly, the inhibition of αSN fibrillation and elimination of toxic aggregates are the main therapeutic strategies. Skullcapflavone II (S.FII), a compound isolated from S. pinnatifida, has shown multiple neuroprotective features. Herein, we demonstrated that S.FII inhibited αSN aggregation with IC50 of 7.2 µM. It increased nucleation time and decreased fibril elongation rate and the species formed in the presence of S.FII were unable to act as seeds. Additionally, S.FII inhibited both secondary nucleation and seeding of αSN and disaggregated the mature preformed fibrils as well. The species formed in the presence of S.FII showed less toxicity. It also preserved neurite length and dopamine content of SH-SY5Y cells and attenuated the inflammatory responses in mixed glial cells. The Localized Surface Plasmon Resonance (LSPR) analysis indicated that S.FII interacts with αSN. Docking simulation studies on αSN fibrils revealed that S.FII could interact with the key residues of the salt bridges and glutamine ladder, which might lead to the destruction of fibril's structures. We also showed that S.FII passes through the blood-brain barrier in vitro and in vivo. Overall, these findings elucidate the neuroprotective roles of S.FII in reducing αSN pathogenicity.

Multiple neuroprotective features of Scutellaria pinnatifida-derived small molecule.

Parkinson's disease (PD) is one of the most prevalent neurodegenerative disorders with no precise etiology. Multiple lines of evidence support that environmental factors, either neurotoxins or neuroinflammation, can induce Parkinsonism. In this study, we purified an active compound, neobaicalein (Skullcapflavone II), from the roots of Scutellaria pinnatifida (S. pinnatifida). Neobaicalein not only had protective impacts on rotenone-induced neurotoxicity but in glial cultures, it dampened the inflammatory response when stimulated with lipopolysaccharide (LPS). Neobaicalein had high antioxidant activity without any obvious toxicity. In addition, it could raise the cell viability, decrease early apoptosis, reduce the generation of reactive oxygen species (ROS), and keep the neurite's length normal in the treated SH-SY5Y cells. Pathway enrichment analysis (PEA) and target prediction provided insights into the PD related genes, protein-protein interaction (PPI) network, and the key proteins enriched in the signaling pathways. Furthermore, docking simulation (DS) on the proteins of the PD-PPI network revealed that neobaicalein might interact with the key proteins involved in PD pathology, including MAPK14, MAPK8, and CASP3. It also blocks the destructive processes, such as cell death, inflammation, and oxidative stress pathways. Our results demonstrate that neobaicalein alleviates pathological effects of factors related to PD, and may provide new insight into PD therapy.

TP53 rs1625895 is Related to Breast Cancer Incidence and Early Death in Iranian Population.

Breast cancer as the second most common cancer worldwide tend to be experienced by Iranian women 10 years earlier with a peak incidence at the premenopausal stage. Genetic mutations of TP53 tumor suppressor gene has been shown to be related to early onset of breast cancer. It has been shown already that rs1625895 polymorphic site is related to glioma as well as lung cancer. In this study, we have investigated the role of rs1625895 polymorphism in breast cancer incidence in Iranian women. DNA extraction of 86 breast cancer patients and 96 control individuals have been used for allele-specific primer-PCR and genotyping of allele A and allele G of the TP53 rs1625895. Genotypes frequencies have been shown that GG homozygosis as the most frequent genotype is a significant association with increased risk of breast cancer development in Iranian women (odds ratio = 6, p = 0.002). On the other hand and in comparison to allele G, allele A could cause early death of breast cancer patients by threefolds significantly (p = 0.011). As a conclusion, we show that allele A is the minor allele in both breast cancer patients and also control individuals and major allele G, is related to the increased risk of breast cancer development in Iranian women.

The primary neuronal cells are more resistant than PC12 cells to α-synuclein toxic aggregates.

BACKGROUND: Alpha-synuclein (αSN) is an abundant presynaptic brain protein that its aggregated species believed to play pivotal roles in the development of neurodegenerative diseases, especially Parkinson's disease (PD). In this study, we compared the response of primary neuronal cells with a well-known cell line model, PC12, against the toxic aggregates of αSN. METHODS: Primary hippocampal neurons (PHNs) were isolated from 17 to 18 days old rat embryos. Fibrillization was induced in recombinant αSN and monitored by standard methods. The toxicity of different aggregates of αSN on the treated cells was then studied. Furthermore, changes in the intracellular reactive oxygen species (ROS) and Ca2+ levels were also compared in two kinds of treated cells. We also studied the gene expression profile of certain Ca2+ channels and carriers using the GEO2 database. RESULTS: The viability rate was significantly lower in PC12 versus PHNs, in response to αSN. This is while the intracellular ROS and Ca2+ levels were significantly increased in both cell types. Analysis of microarray data indicated that some factors involved in Ca2+ hemostasis may face significant changes in the PD condition. CONCLUSION: By putting these data together, it is clear that PHN is more resistant than PC12 toward αSN cytotoxicity even in the presence of rising cytoplasmic ROS and Ca2+ levels. Exploring the supporting mechanisms which PHN uses to be more resistant to αSN cytotoxicity can help to open a roadmap toward therapeutic plans in PD and other synucleinopathy disorders.

A detailed image of rutin underlying intracellular signaling pathways in human SW480 colorectal cancer cells based on miRNAs-lncRNAs-mRNAs-TFs interactions.

Natural dietary ingredients like flavonoids are important for body improvement against diseases. The flavonol rutin is widely found in fruits and vegetables and shows significant anticancer properties. However, the underlined signaling pathways have not been elucidated yet. In this study, the impacts of various doses of rutin (400-700 mM/ml) have been examined on human colon cancer SW480 cells metabolism, cell cycle, and apoptosis. The transcriptome was analyzed by bioinformatics tools and the interactions between rutin modulated microRNAs (miRNAs), long noncoding RNAs (lncRNAs), messenger RNAs (mRNAs), and transcription factors (TFs) were built, filtered and enriched. A dose of 600 mM of rutin significantly decreased cells metabolic activity, halved the population and arrested the cell cycle at the sub-G1 phase. The enrichment analysis of miRNAs-lncRNAs-mRNAs-TFs network showed that these effects were mediated through alteration of glucose, lipid, and protein metabolism, modulating endoplasmic reticulum stress responses, negative regulation of cell cycle process, and inducing the extrinsic and intrinsic apoptotic signaling pathways. Additionally, the key parent nodes of each annotation were illustrated. These findings create a detailed image of rutin underlying intracellular signaling pathways in CRC and also help us to better understand the role of dietary natural compounds in cancer treatment.

ErbB4 receptor polymorphism 2368A>C and risk of breast cancer.

PURPOSE: A number of single nucleotide polymorphisms (SNPs) in EebB4 gene have been studied, which has clarified their impact on breast cancer in different populations. Nevertheless, the importance of rs13423759 in breast cancer has not been studied and its effect remained almost unclear. In this paper, we evaluated the frequency of rs13423759 different alleles in Iranian population and statistically analyzed their association with breast cancer risk. MATERIALS AND METHODS: Allele-specific Primer PCR (ASP-PCR) was recruited in this study to genotype rs13423759 position in 172 breast cancer and 148 healthy control subjects. The genotypes of control and cases were analyzed statistically to find the association between rs13423759 alleles and breast cancer incidence and its clinicopathological characteristics. In silico studies were performed in order to find the mechanistic viewpoint of rs13423759 alleles in breast cancer. RESULTS: rs13423759 allele C was shown to be significantly associated with breast cancer risk, HER2 positivity and increased risk of metastasis. Reciprocally, allele A was correlated with the lowered risk of breast cancer. The in silico studies showed that rs13423759 allele C is capable to strengthen the interaction between miR-548as, an oncomiRNA, and ErbB4 mRNA, leading to its lowered concentration in the cells. CONCLUSION: rs13423759 allele C is significantly associated with the enhanced risk of breast cancer, elevated metastasis and HER2 positivity.

Polymorphic GT dinucleotide repeat in the PIK3CA gene and risk of colorectal cancer.

BACKGROUND: Activated PI3K generate PIP3 to trigger different signaling pathways which regulate a number of cellular functions including cell survival, apoptosis, proliferation and motility. Mutations in many cancers were discovered in the gene encoding the PI3K catalytic subunit, PIK3CA. OBJECTIVE: To date, there has been no report on the association between polymorphism of PIK3CA gene microsatellites and risk of colorectal cancer. In this study, we investigate the relation between the GT dinucleotide repeat in intron 1 of the PIK3CA gene and colorectal cancer risk. METHODS: A case-control study of 103 colorectal cancer patients and 150 controls was conducted in Iranian people. RESULTS: The results of our study demonstrate that PIK3CA gene allele distribution in Iranian population varies between 13 and 20 repeats. Here we demonstrate that individuals who carry alleles shorter than 17 GT repeat are at higher risk of developing colorectal cancer (OR = 4.0, p= 0), by contrast, those individuals with two alleles longer than 16 GT repeats are at a significantly lower risk of developing colorectal cancer (OR = 0.12, p= 0). CONCLUSION: This result suggests polymorphic GT repeat of PIK3CA gene may be a potential predictive marker of colorectal cancer risk in Iranian population.