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Antibodies against Aß amyloid are indispensable research tools and potential therapeutics for Alzheimer's disease. They display several unusual properties, such as specificity for aggregated forms of the peptide, the ability to distinguish polymorphic aggregate structures, and the ability to recognize generic aggregation-related epitopes formed by unrelated amyloid sequences. Understanding the mechanisms underlying these unusual properties and the structures of their corresponding epitopes is crucial for the understanding why antibodies display different therapeutic activities and for the development of more effective therapeutic agents. Here we employed a novel "epitomic" approach to map the fine structure of the epitopes of 28 monoclonal antibodies against amyloid-beta using immunoselection of random sequences from a phage display library, deep sequencing, and pattern analysis to define the critical sequence elements recognized by the antibodies. Although most of the antibodies map to major linear epitopes in the amino terminal 1 to 14 residues of Aß, the antibodies display differences in the target sequence residues that are critical for binding and in their individual preferences for nontarget residues, indicating that the antibodies bind to alternative conformations of the sequence by different mechanisms. Epitomic analysis also identifies discontinuous, nonoverlapping sequence Aß segments that may constitute the conformational epitopes that underlie the aggregation specificity of antibodies. Aggregation-specific antibodies recognize sequences that display a significantly higher predicted propensity for forming amyloid than antibodies that recognize the monomer, indicating that the ability of random sequences to aggregate into amyloid is a critical element of their binding mechanism.

Antibodies against Aß amyloid are indispensable research tools and potential therapeutics for Alzheimer's disease. They display several unusual properties, such as specificity for aggregated forms of the peptide, the ability to distinguish polymorphic aggregate structures, and the ability to recognize generic aggregation-related epitopes formed by unrelated amyloid sequences. Understanding the mechanisms underlying these unusual properties and the structures of their corresponding epitopes is crucial for the understanding why antibodies display different therapeutic activities and for the development of more effective therapeutic agents. Here we employed a novel "epitomic" approach to map the fine structure of the epitopes of 28 monoclonal antibodies against amyloid-beta using immunoselection of random sequences from a phage display library, deep sequencing, and pattern analysis to define the critical sequence elements recognized by the antibodies. Although most of the antibodies map to major linear epitopes in the amino terminal 1 to 14 residues of Aß, the antibodies display differences in the target sequence residues that are critical for binding and in their individual preferences for nontarget residues, indicating that the antibodies bind to alternative conformations of the sequence by different mechanisms. Epitomic analysis also identifies discontinuous, nonoverlapping sequence Aß segments that may constitute the conformational epitopes that underlie the aggregation specificity of antibodies. Aggregation-specific antibodies recognize sequences that display a significantly higher predicted propensity for forming amyloid than antibodies that recognize the monomer, indicating that the ability of random sequences to aggregate into amyloid is a critical element of their binding mechanism.

Human hepatocellular carcinoma (HCC) is the most common and recurrent type of primary adult liver cancer without any effective therapy. Plant-derived compounds acting as anticancer agents can induce apoptosis by targeting several signaling pathways. Strigolactone (SL) is a novel class of phytohormone, whose analogues have been reported to possess anticancer properties on a panel of human cancer cell lines through inducing cell cycle arrest, destabilizing microtubular integrity, reducing damaged in the DNA repair machinery, and inducing apoptosis. In our previous study, we reported that a novel SL analogue, TIT3, reduces HepG2 cell proliferation, inhibits cell migration, and induces apoptosis. To decipher the mechanisms of TIT3-induced anticancer activity in HepG2, we performed RNA sequencing and the differential expression of genes was analyzed using different tools. RNA-Seq data showed that the genes responsible for microtubule organization such as TUBB, BUB1B, TUBG2, TUBGCP6, TPX2, and MAP7 were significantly downregulated. Several epigenetic modulators such as UHRF1, HDAC7, and DNMT1 were also considerably downregulated, and this effect was associated with significant upregulation of various proapoptotic genes including CASP3, TNF-α, CASP7, and CDKN1A (p21). Likewise, damaged DNA repair genes such as RAD51, RAD52, and DDB2 were also significantly downregulated. This study indicates that TIT3-induced antiproliferative and proapoptotic activities on HCC cells could involve several signaling pathways. Our results suggest that TIT3 might be a promising drug to treat HCC.

Background: Skin infection by Methicillin-Resistant Staphylococcus aureus (MRSA) is a common disease in Saudi Arabia. This bacterium is resistance to Methicillin and other antibiotics. Skin and soft tissue are the greatest common infected areas by these strains include abscesses, wound infections and other diseases. Materials and Methods: This study evaluated the in vitro antibacterial action of different plants extracts using different solvents from Saudi Arabia against MRSA. Different Plants were extracted by different solvents: methanol, chloroform and n-hexane. Agar well diffusion method was used to determine antibacterial efficacy with 100 µL (5 mg /0.5 mL) of plant extracts. Results: Minimum inhibitory concentration was determined on plant extracts that showed high effectiveness against MRSA. Conclusion: The obtained from Gas chromatography/mass spectrum analysis of the most active four plants, revealed the active volatile oils and flavonoids contents of Artemisia monosperma, Mentha longifolia, Vernonia schimperi and Rumex nervosu have antibacterial activity against MRSA. These plants demonstrate promising anti-MRSA potential. [ABSTRACT FROM AUTHOR]

Background: Herbal medicine and its bioproducts are rich in bioactive compounds that promising in drug development. These phytochemical constituents may be secondary metabolites that exert high potency. Materials and Methods: This study investigated the phyto-constituents bioactive compounds from the aerial parts of some Saudi medicinal plants using n-hexane extracts (Trichodesma trichodesmoides, Baccharoides schimperi, Anabasis articulate and Achillea fragrantissima) and a mixture of essentials oils in equal ratio (Arnica montana, Chamomile, Salvia officinalis, Oenothera, Walnut leaves and Flaxseed) using GC-MS. Results: The GC-MS analysis of plants and essentials oils revealed the presence of various compounds like terpenoids and vitamins related to its anti-microbial activity, antioxidant and anti-inflammatory activity. Conclusion: It was concluded that, the broad range of terpenoids and vitamins are the main components in the hexane extract. These possess different biological activities. Further studies will be carried out in vivo and in vitro to identify the mechanism of action via signaling pathway. [ABSTRACT FROM AUTHOR]

Introduction: Atherosclerosis is common CHD caused by accumulation of oxidized LDL-c forming foam cell with macrophage that narrowing blood vessels. It increased risk of CVD. Green vegetables rich with PUFA is important to maintain healthy status. This study investigated the mechanistic pathway mediate combination of Decosapentanoic acid (DPA) and linoleic acid (LA) as anti-atherothengic effect in rats fed high fat diet. Materials and Methods: Seventy-five male albino rats were divided into five groups (15 rats each) were fed high fat diet (40% Saturated fat) for 3 months: Group (I): Rats given 10 % DPA. Group (II): Rats given 10 % LA. Group (III): Rats given 10 % DPA+10% LA. Group (IV): Rats treated with atorvastatin (10 mg/kg BW) and Group (v) Untreated. In addition, Group (VI): 15 rats fed normal diet. Results: Data obtained showed that, plasma cholesterol and LDL-c levels were highly significant reduced in group III (p < 0.001) versus other groups compared with untreated. Level of triglycerides was reduced but still high than normal (p=0.05) and atherogenic index. The activity of HMG-CoA reductase was reduced while apo-A, apo-c elevated, JAK was upregulated in combination therapy (p< 0.001). The elevated Apo-A, apo-c activate clearing factor and decreased triglycerides. Conclusion: It was concluded that, upregulated of JAK by combination therapy mediate inhibition of HMG-CoA reductase that decreased endogenous synthesis of cholesterol and reduced its level in circulation. [ABSTRACT FROM AUTHOR]

Autophagy is a protective mechanism important in human diseases as cancer. We evaluated the impact of khalas date extract (KDE) (20-60 mg/mL) on cell viability, morphological changes, DNA fragmentation and gene expression of LC3B-II associated with autophagosome on HepG2 cell line. The GC/MS identification of KDE showed its high content of flavonoids including quercetin, myricetin, kaempferol and catechol. KDE reduced cell viability of HepG2 with IC50 (31.52 mg/mL). Cells treated with KDE showed two band of DNA fragments at (30 and 40 mg) indicating that KDE induced DNA damage and apoptosis in HepG2. The analysis RT-PCR data showed a 0.2-fold increase in the expression of LC3-B in the cells treated with KDE versus control. We concluded that, KDE flavonoids such as quercetin, myricetin kaempferol exhibited anticancer properties manifested by inhibition of HepG2 cell viability and induction of apoptosis and upregulation of the pro-autophagy LC3-B gene. [ABSTRACT FROM AUTHOR]

The current study identified the specific antibodies that recognise amyloid protein for Alzheimer disease – immunotherapy. The immune-selection of random sequences from a phage display library and sequencing to obtain the random 12 amino acids peptide library for each antibody, and then we analysed these peptides for unique and common sequences, relation to Aβ42 sequence and shape and pattern of the amino acid reaction to the antibody to predict the epitopes. Data obtained for 4G8 showed that, the sequence segment related to the putative epitope of 4G8 was LVFFAED. Nine of the ten top sequences contain the sequence RHD corresponding to the Aβ sequence from residues 5-7. Peptide 7 has the sequence IRYDTGSYHIH, which has a RYD. It was concluded that, 4G8 and 6E10 can tolerate the binding the sequences that explain it is able to recognise amyloid aggregates. [ABSTRACT FROM AUTHOR]

Alzheimer's disease (AD) is atrophy of brain cells that lead to decline in the mental capacity and memory. This study investigated the mechanism which postulates that intraneuronal accumulation of amyloid aggregates for pathogenesis of AD. The PC12 cell line was used to examine the amyloid beta (Aβ) aggregation in different stages. It was found that dot-blot filter retardation assay for Ub-CTF was 0.25 and 0.2 µM for SS-CTF. In addition, incubation of SS-CTF with 200 µM Aβ-42 then bounded with an antibody directed against Aβ. It was suggested that most bound Aβ-42 in the oligomeric form. Confocal microscope showed that stained with DAPI (blue) in the neuritic plaques, APP-GFP (green) and specific monoclonal M78 (red). Aß oligomeric taken up by neurons and accumulation of misfolded Aß aggregates continue in a perinuclear location. Fluorescence intensities correlate with the priming effect observed on the Aβ (p <.001). It was concluded that a new amyloid hypothesis is promising in therapy development to reduce the incidence of disease by inhibition of intraneuronal amyloid aggregation. [ABSTRACT FROM AUTHOR]