Evaluation of the effect of designed PLGA-arctiin nanoparticles modified with folic acid and chitosan on colon cancer cells.

In this study, we designed nanoparticles (NPs) based on polylactic acid glycolic acid modified with chitosan and folic acid to optimize the anti-cancer, anti-inflammatory, and antioxidant effects of arctiin (ARC), and we measured its effects on cancer cells, including colon cancer. NPs were synthesized using the W1/O/W2 double-emulsion solvent evaporation method. Physicochemical characteristics of synthesized NPs (ARC-PCF-NPs), including average particle size, dispersity index (PDI), zeta potential (ZP), field emission scanning electron microscope figures, and encapsulation efficiency (EE), were evaluated. 2,2'-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), 2,2-diphenyl-1-picrylhydrazyl (DPPH), and ferric reducing antioxidant power (FRAP) methods were carried out to determine the antioxidant properties of NPs. 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide assay was performed to investigate cytotoxicity effects on cancer cells and normal fibroblasts. Quantitative polymerase chain reaction was also performed on inflammatory and antioxidant genes. The obtained results indicated that the synthesized NPs have a size of 100 nm, a DPI of 0.36, a ZP of 26.30 mV, and EE was calculated at about 87.5%. The antioxidant influence of ARC-PCF-NPs was confirmed by inhibiting ABTS and DPPH free radicals and ferrous reduction in the FRAP method. Moreover, the reduction of inflammatory and antioxidant genes confirmed the anti-inflammatory and antioxidant properties of NPs. These results indicate the modification of the surface of NPs in order to increase the bioavailability, stability, and effectiveness of medicinal compounds in therapeutic applications.

Investigation of the expression of Cis P-tau and Pin1 proteins following air pollution induction in the brain tissue of C57BL/6 mice.

Alzheimer's disease (AD) is a multifactorial disease in which environmental factors play a role. Among environmental factors, air pollution is a vital issue in modern life. Despite extensive considerations, it remains uncertain how pollution mediates neurodegeneration in AD. Beta-amyloids and hyperphosphorylated tau proteins are the two main pathological markers that have been studied in AD so far. Tau protein is basically a phosphoprotein whose functions are controlled by phosphorylation. The function of tau protein is to be located on the surface of microtubules and stabilize them. Studies have shown that phosphorylated tau protein (p-tau) exists in cis and trans conformations at Thr231, among which cis is highly neurotoxic. The Pin1 enzyme performs the conversion of cis to trans or vice versa. In this study, an experimental mouse model was designed to investigate the formation of cis p-tau by inducing air pollution. In this way, mice were randomly exposed to pollution at 2-week, 1-month, and 2-month intervals. We investigated the formation of phosphorylated cis tau form during air pollution on mouse brains using Western blots and immunofluorescence. The fluorescent imaging results and Western blotting analysis of mouse brains revealed a significant accumulation of cis p-tau in pollution-treated mice models compared to the healthy control mice. According to Western blot results, air pollution induction caused a significant decrease in Pin1 protein. The results clearly show that the tauopathy observed during air pollution is mediated through the formation of cis tau. Our findings unravel tauopathy mysteries upon pollution and would help find a possible therapeutic target to fight the devastating disorder caused by modern life.

Benzenesulfonamide as a novel, pharmaceutical small molecule inhibitor on Aß gene expression and oxidative stress in Alzheimer's Wistar rats.

Alzheimer's disease (AD) is the most prevalent acute neurodegenerative disease described by memory loss and other cognitive functions. Benzenesulfonamide, a novel, potent, and small organic molecule, was synthesized to investigate its effects on the levels of oxidative biomarkers (GPx, ROS, and MDA) and expression of beta-amyloid peptides (Aß40 and Aß42) in the pathology of AD. The results were compared with the rivastigmine drug. Applying benzenesulfonamide to Alzheimer's-induced Wistar rats showed a significant increase in the level of oxidative biomarkers (GPx, ROS, and MDA) in both the brain and blood serum as well as amyloid-ß40 and 42 gene expressions. Therefore, benzenesulfonamide could be considered a novel therapeutic agent against AD.

Anti-Microbial Peptides: Strategies of Design and Development and Their Promising Wound-Healing Activities.

BACKGROUND: Current approaches used to overcome microbial infections are becoming inefficient due to the overuse or misuse of antibiotics. Antimicrobial peptides (AMPs) are one of the most promising substitutional candidates for commercial antibiotics. METHODS AND RESULTS: The publications in the field of in silico design of AMPs with focus on the wound-healing AMPs were searched though SCOPUS and PubMed. Through publications, it was reported that a number of AMPs approved for clinical use have also showed efficient wound-healing activity. Todays, the design and production of synthetic types of AMPs have attracted attention in order to expand their applications and to cope with their limitations and adverse effects. In this paper, the currently published researches in the field of AMPs and their wound-healing features were summarized and the strategies used in AMPs design and development have been reviewed. Moreover, different databases and online servers used in this regard were summarized. CONCLUSION: Design and development of active AMPs, especially those with wound-healing activity, can be performed using bioinformatics servers and software, regarding AMPs structure-activity relationships.

Interaction of Aß(25-35) fibrillation products with mitochondria: Effect of small-molecule natural products.

The 25-35 fragment of the amyloid ß (Aß) peptide is a naturally occurring proteolytic by-product that retains the pathophysiology of its larger parent molecule, whose deposition has been shown to involve mitochondrial dysfunction. Hence, disruption of Aß(25-35) aggregates could afford an effective remedial strategy for Alzheimer's disease (AD). In the present study, the effect of a number of selected small-molecule natural products (polyphenols: resveratrol, quercetin, biochanin A, and indoles: indole-3-acetic acid, indole-3-carbinol (I3C)) on Aß(25-35) fibrillogenesis was explored under physiological conditions, and interaction of the resulting structures with rat brain mitochondria was investigated. Several techniques, including fluorescence, circular dichroism, and transmission electron microscopy were utilized to characterize the aggregation products, and possible mitochondrial membrane permeabilization was determined following release of marker enzymes. Results demonstrate the capacity of Aß(25-35) fibrils to damage mitochondria and suggest how small molecules may afford protection. While I3C appeared more effective in inhibiting the fibrillation process, all natural products behaved similarly in destabilizing preformed aggregates. It is concluded that elucidation of such protection may provide important insights into the development of preventive and therapeutic agents for AD.

Promising anti-inflammatory activity of a novel designed anti-microbial peptide for wound healing.

Chronic wounds can develop as a result of prolonged inflammation during the healing process, which can happen due to bacterial infection. Therefore, preventing infection and controlling inflammation can accelerate wound healing. Antimicrobial peptides have different protective properties in addition to antimicrobial activity. Some of these activities include the stimulation of cytokine or chemokine synthesis, the facilitation of chemotaxis and cell proliferation, the acceleration of cell proliferation, the induction of anti-inflammatory responses, and the promotion of wound repair. This study aimed to assess the wound healing potential of a novel in silico-designed antimicrobial peptide. Then, its anti-inflammatory activity was investigated by measuring the level of tumor necrosis factor-α (TNF-α) and transforming growth factor beta (TGF-ß) as indicators of the wound healing process. In addition, the influence of the peptide on cell migration was evaluated by a scratch test on human dermal fibroblasts (HDF) and HaCaT cells as a human epidermal keratinocyte cell line. The results showed that our new peptide could act well in inhibiting TNF-α over-secretion while increasing the expression of TGF-ß as an anti-inflammatory factor. This peptide showed a significant potential to stimulate HDF and HaCaT cell migration and proliferation. Therefore, using this peptide as an anti-inflammatory component of wound dressings may be promising.

Preparation and Characterization of Allicin-Loaded Solid Lipid Nanoparticles Surface-Functionalized with Folic Acid-Bonded Chitosan: In Vitro Anticancer and Antioxidant Activities.

OBJECTIVE: This investigation aimed to increase the bioavailability and anticancer effects of allicin (AC) by encapsulating it in solid lipid nanoparticles (SLN) decorated with chitosan (CS)-conjugated folic acid (FA). MATERIAL AND METHODS: Nanoparticles (NPs) were synthesized by high-pressure homogenization, and then, Fourier-transform infrared (FTIR), Field-Emission Scanning Electron Microscopy (FESEM), Dynamic Light Scattering (DLS), and zeta potential methods were used to determine their physicochemical characteristics. 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was performed to assess the effect of toxicity and flow cytometry, while fluorescent staining methods were used to investigate the type of cell death. Real-time quantitative polymerase chain reaction (qPCR) was used to evaluate the expression levels of apoptotic genes: Bcl-2, and caspase-8. RESULTS: The presence of AC-SLN-CS-FA with a spherical morphology, an average size of 86.7 ± 9.4 nm, uniform distribution (0.31), a surface charge of +21.3 ± 13.3 mV, an encapsulation percentage of 86.3%, and a folate binding rate of 63% confirmed the success of the preparation method. Suppression of MCF-7 cancer cells and non-toxicity of AC-SLN-CS-FA on Human foreskin fibroblast (HFF) normal cells were confirmed by cytotoxic assay. The results of flow cytometry revealed that the cells were arrested in the sub-G1 phase, and the activation of the intrinsic apoptosis pathway was confirmed by the results of real-time qPCR. CONCLUSIONS: In general, AC-SLN-CS-FA has the potential to prevent free radicals and trigger apoptosis in cancer cells by activating the intrinsic apoptosis pathway; thus, making it a promising subject in preclinical research.

Synthesis of Novel Magnetic Quercetin-Neuropeptide Nanocomposite as a Smart Nano-Drug Shuttle System: Investigation of Its Effect on Behavior, Histopathological Characteristics, and Expression of MAPT and APP Genes in Alzheimer's Disease Rats.

BACKGROUND: Alzheimer's disease (AD) is the most common type of dementia. The drugs introduced for this disease have many side effects and limitations in use, so the production of a suitable herbal medicine to cure AD patients is essential. OBJECTIVE: The aim of this research is to make a magnetic neuropeptide nano shuttle as a targeted carrier for the transfer of quercetin to the brains of AD model rats. METHODS: In this work, a magnetic quercetin-neuropeptide nanocomposite (MQNPN) was fabricated and administered to the rat's brain by the shuttle drug of the Margatoxin scorpion venom neuropeptide, and will be a prospect for targeted drug delivery in AD. The MQNPN has been characterized by FTIR, spectroscopy, FE-SEM, XRD, and VSM. Investigations into the efficacy of MQNPN, MTT, and real Time PCR for MAPT and APP genes expression were performed. After 7 days treatment with Fe3O4 (Ctr) and MQNPN treatment in AD rat, superoxide dismutase activity and quercetin in blood serum and brain was detected. Hematoxylin-Eosin staining was applied for histopathological analysis. RESULTS: Analysis of data showed that MQNPN increased the activity of superoxide dismutase. The histopathology results of the hippocampal region of AD rats also confirmed their improvement after treatment with MQNPN. MQNPN treatment caused a significant decrease in the relative expression of MAPT and APP genes. CONCLUSION: MQNPN is a suitable carrier for the transfer of quercetin to the rat hippocampus, and has a significant effect in reducing AD symptoms in terms of histopathology, behavioral testing, and changing the expression of AD-related genes.

The anticancer, anti-oxidant, and antibacterial activities of chitosan-lecithin-coated parthenolide/tyrosol hybrid nanoparticles.

Tyrosol (TYR) and parthenolide (PLT) have been used as synthetic antioxidant and natural anticancer compounds. In the current study, we aimed to synthesize an encapsulated complex of both PLT and TYR in a hybrid coating layer consisting of lecithin and chitosan molecules, a proper biocompatible drug delivery system to evaluate its antibacterial and anticancer potentials on human liver HepG2 and pancreatic Panc cancer cell lines. The chitosan-lecithin-coated PLT/TYR nanoparticles (clPT-NPs) were synthesized applying an auto-self-assembling method. The clPT-NPs were characterized utilizing DLS, FTIR, zeta potential, and TEM analysis. The clPT-NPs' antioxidant activity was measured by running ABTS and DPPH antioxidant assays. Moreover, the antibacterial potential of clPT-NPs was evaluated by applying disk diffusion, MIC, and MBC assays. Finally, the nanoparticles' cytotoxicity and apoptotic activity were studied by conducting MTT, Flow cytometry, AO/PI cell staining, and real-time PCR techniques. The clPT-NPs (38 nm) exhibited significant antioxidant activity by inhibiting ABTS and DPPH radicals at 187 and 290 µg/mL IC50 concentrations, respectively. Also, the nanoparticles induced a notable antibacterial activity against Staphylococcus aureus at 0.0625 mg/mL MIC and 0.125 mg/mL MBC concentrations. The clPT-NPs selectively decreased the cancer cells' survival and increased the apoptotic dead cells by up-regulating apoptotic gene expression (BAX and Cas-8) and down-regulating BCL-2 anti-apoptotic gene expression. The PLT toxicity has been merged with improved TYR antioxidant activity, which has been functionalized in a safe, biocompatible hybrid nano-delivery system.

Design and Evaluation of a Novel Anti-microbial Peptide from Cathelicidin-2: Selectively Active Against Acinetobacter baumannii.

Background: Infections caused by pathogenic microorganisms have increased the need for hospital care and have thus represented a public health problem and a significant financial burden. Classical treatments consisting of traditional antibiotics face several challenges today. Anti-microbial peptides (AMPs) are a conserved characteristic of the innate immune response among different animal species to defend against pathogenic microorganisms. Objectives: In this study, a new peptide sequence (mCHTL131-140) was designed using the in silico approach. Methods: Cathelicidin-2 (UniprotID: Q2IAL7) was used as a potential antimicrobial protein, and a novel 10 - 12 amino acids sequence AMP was designed using bioinformatics tools and the AMP databases. Then, the anti-bacterial, anti-biofilm, and anti-fungal properties of the peptide, as well as its hemolytic activity and cytotoxicity towards human fibroblast (HDF) cells, were investigated in vitro. Results: Online bioinformatics tools indicated that the peptide sequence could have anti-bacterial, anti-viral, anti-fungal, and anti-biofilm properties with little hemolytic properties. The experimental tests confirmed that mCHTL131-140 exhibited the best anti-bacterial properties against Acinetobacter baumannii and had fair anti-fungal properties. Besides, it did not cause red blood cell lysis and showed no cytotoxicity towards HDF cells. Conclusions: In general, the designed peptide can be considered a promising AMP to control hospital-acquired infections by A. baumannii.

Purification of Therapeutic Serums of Snake Anti-Venom with Caprylic Acid.

Objectives: Antivenom serums have been used extensively for over a century and are the only effective treatment option for snake bites and other dangerous animal envenomations. In therapeutic serum centers, a wide range of antivenoms is made from animal serum, mainly equine and sheep, that are immunized with single or multiple venoms. This work aimed to use caprylic acid (CA) to purify therapeutic snake antivenom. Methods: Plasma was obtained from equine immunized with a mixture of venoms. Immunized plasma was obtained by precipitation of different concentrations (2-5%) of CA. This methodology was compared to that based on ammonium sulfate (AS) precipitation. Sediment plasma proteins were purified by ion-exchange chromatography. Protein assay, SDS-PAGE, and agar gel diffusion were performed. Results: The total protein precipitation with AS was higher than precipitation with CA, but the best results were obtained when CA was added to the plasma until a final CA concentration of 5% was reached. Chromatography and electrophoresis indicated a stronger band for the 5% CA, and the gel diffusion assay showed antigen-antibody interaction in the purified serum. Conclusion: The use of CA compared to the routine method for purifying hyperimmune serums is a practical and cost-effective method for preparing and producing therapeutic serums. It constitutes a potentially valuable technology for alleviating the critical shortage of antivenom in Iran.

Cymene consumption and physical activity effect in Alzheimer's disease model: an in vivo and in vitro study.

PURPOSE: Alzheimer's disease (AD) is one of the most important neurodegenerative diseases and accompanied by the production of free radicals and inflammatory factors. Studies have shown that p-cymene has anti-inflammatory and anti-oxidant effects. Here, the effects of this compound were investigated on a rat model of AD. METHODS: In order to create Alzheimer's rat model, bilateral injection of Amyloid ß1-42 (Aß1-42) into rats hippocampus was performed. Both therapeutic (post-AD induction) and preventive effects of p-cymene consumption with doses of 50 and 100 mg/kg were investigated. In addition, the effects of adding short-term exercise to the process were also observed. In vitro, Aß1-42 peptide was driven toward fibril formation and effect of p-cymene was observed on the resulting fibrils. RESULTS: Learning and memory indices in the AD rats were significantly reduced compared to the Sham group, while p-cymene consumption with both doses, as well as performing exercise counteracted AD consequences. Moreover, increased neurogenesis and reduced amyloid plaques counts were observed in treated rats. In vitro formed fibrils of Aß1-42 were partially disaggregated in the presence of p-cymene. DISCUSSION: p-Cymene could act on this AD model via antioxidant and anti-inflammatory properties as well as direct anti-fibril effect. CONCLUSION: p-cymene can improve AD-related disorders including memory impairment.

An investigation into non-covalent functionalization of a single-walled carbon nanotube and a graphene sheet with protein G:A combined experimental and molecular dynamics study.

Investigation of non-covalent interaction of hydrophobic surfaces with the protein G (PrG) is necessary due to their frequent utilization in immunosensors and ELISA. It has been confirmed that surfaces, including carbonous-nanostructures (CNS) could orient proteins for a better activation. Herein, PrG interaction with single-walled carbon nanotube (SWCNT) and graphene (Gra) nanostructures was studied by employing experimental and MD simulation techniques. It is confirmed that the PrG could adequately interact with both SWCNT and Gra and therefore fine dispersion for them was achieved in the media. Results indicated that even though SWCNT was loaded with more content of PrG in comparison with the Gra, the adsorption of the PrG on Gra did not induce significant changes in the IgG tendency. Several orientations of the PrG were adopted in the presence of SWCNT or Gra; however, SWCNT could block the PrG-FcR. Moreover, it was confirmed that SWCNT reduced the α-helical structure content in the PrG. Reduction of α-helical structure of the PrG and improper orientation of the PrG-SWCNT could remarkably decrease the PrG tendency to the Fc of the IgG. Importantly, the Gra could appropriately orient the PrG by both exposing the PrG-FcR and also by blocking the fragment of the PrG that had tendency to interact with Fab in IgG.

Protein G selects two binding sites for carbon nanotube with dissimilar behavior; a molecular dynamics study.

BACKGROUND: Study of nanostructure-protein interaction for development of various types of nano-devices is very essential. Among carbon nanostructures, carbon nanotube (CNT) provides a suitable platform for functionalization by proteins. Previous studies have confirmed that the CNT induces changes in the protein structure. METHODS: Molecular dynamics (MD) simulation study was employed to illustrate the changes occurring in the protein G (PGB) in the presence of a CNT. In order to predict the PGB surface patches for the CNT, Autodock tools were utilized. RESULTS: Docking results indicate the presence of two different surface patches with diverse amino acids: the dominant polar residues in the first (PGB-CNT1) and the aromatic residues in the second (PGB-CNT2) surface patch. Displacement of amino acids in the PGB-CNT2 complex occurred during the simulation and it caused an increase in its stability at the end of simulation. The amino acids' displacements diminished the PGB α-helix structure by breakage of hydrogen bonds and generated more transient structures. Principal component analysis determined that the interaction of the CNT with the second surface patch of the PGB raised the extent and modes of the PGB motions. In contrast, insignificant structural changes induced in the PGB while the CNT bonded through the first surface patch. CONCLUSION: Even though neither of the PGB-CNT complexes could prevent structural changes in the PGB, development of the PGB-CNT1 complex induce slight structural changes in its fragment of crystallizable receptor (FCR). Dissimilar structural changes induced in the PGB-CNT complexes are possibly related to various characteristics of the PGB binding sites.

A study on alpha-terpineol in Alzheimer's disease with the use of rodent in vivo model, restraint stress effect and in vitro Amyloid beta fibrils

Abstract Alzheimer's disease (AD) is a neurological disorder in which the neuronal degeneration is associated with inflammatory processes and oxidative stress. Since alpha-terpineol was shown to possess antioxidant and anti-inflammatory effects, the administration of this compound was studied on a rat model of AD. To create this model, Aβ1-42 was injected into the hippocampus of male Wistar rats. Generated AD models were divided into simple AD models and AD models in which short-term immobilization stress was added. Preventive and therapeutic (post-AD induction) effects of alpha-terpineol consumption (100 mg/Kg) were subsequently investigated in AD models, which were compared with control groups. Biochemical factors (superoxide dismutase and malondialdehyde), histological manifestations (amyloid plaques and neuron counts) and possible memory impairment (shuttle-box experiment) were investigated in all groups. For the in vitro experiment, alpha-terpineol effect was checked on Aβ1-42 fibril formation. In preventive and therapeutic modes, alpha-terpineol consumption could improve neurogenesis and long-term memory while reducing amyloid plaque counts and ameliorating biochemical factors (higher levels of superoxide dismutase and malondialdehyde and reduced levels of MDA). In vitro, shorter fibrillar structures were formed in the presence of alpha-terpineol, which indicates an anti-amyloid effect for this compound. In conclusion, alpha-terpineol significantly counteracted AD consequences.

Inhibition of HEWL fibril formation by taxifolin: Mechanism of action.

Among therapeutic approaches for amyloid-related diseases, attention has recently turned to the use of natural products as effective anti-aggregation compounds. Although a wealth of in vitro and in vivo evidence indicates some common inhibitory activity of these compounds, they don't generally suggest the same mechanism of action. Here, we show that taxifolin, a ubiquitous bioactive constituent of foods and herbs, inhibits formation of HEWL amyloid fibrils and their related toxicity by causing formation of very large globular, chain-like aggregates. A range of amyloid-specific techniques were employed to characterize this process. We found that taxifolin exerts its effect by binding to HEWL prefibrillar species, rather than by stabilizing the molecule in its native-like state. Furthermore, it's binding results in diverting the amyloid pathway toward formation of very large globular, chain-like aggregates with low ß-sheet content and reduced solvent-exposed hydrophobic patches. ThT fluorescence measurements show that the binding capacity of taxifolin is significantly reduced, upon generation of large protofibrillar aggregates at the end of growth phase. We believe these results may help design promising inhibitors of protein aggregation for amyloid-related diseases.