Design of a peptide-based vector, PepFect6, for efficient delivery of siRNA in cell culture and systemically in vivo

While small interfering RNAs (siRNAs) have been rapidly appreciated to silence genes, efficient and non-toxic vectors for primary cells and for systemic in vivo delivery are lacking. Several siRNA-delivery vehicles, including cell-penetrating peptides (CPPs), have been developed but their utility is often restricted by entrapment following endocytosis. Hence, developing CPPs that promote endosomal escape is a prerequisite for successful siRNA implementation. We here present a novel CPP, PepFect 6 (PF6), comprising the previously reported stearyl-TP10 peptide, having pH titratable trifluoromethylquinoline moieties covalently incorporated to facilitate endosomal release. Stable PF6/siRNA nanoparticles enter entire cell populations and rapidly promote endosomal escape, resulting in robust RNAi responses in various cell types (including primary cells), with minimal associated transcriptomic or proteomic changes. Furthermore, PF6-mediated delivery is independent of cell confluence and, in most cases, not significantly hampered by serum proteins. Finally, these nanoparticles promote strong RNAi responses in different organs following systemic delivery in mice without any associated toxicity. Strikingly, similar knockdown in liver is achieved by PF6/siRNA nanoparticles and siRNA injected by hydrodynamic infusion, a golden standard technique for liver transfection. These results imply that the peptide, in addition to having utility for RNAi screens in vitro, displays therapeutic potential

Antagonist Temperature Variation Affects the Photosynthetic Parameters and Secondary Metabolites of <i>Ocimum basilicum</i> L. and <i>Salvia officinalis</i> L.

Climate change is one of the main challenges for actual and future generations. Global warming affects plants and animals and is responsible for considerable crop loss. This study studied the influence of antagonist successive stresses, cold–heat and heat–cold, on two medicinal plants Ocimum basilicum L. and Salvia officinalis L. The photosynthetic parameters decreased for plants under the variation of subsequent stress. Net assimilation rates and stomatal conductance to water vapor are more affected in the case of plants under cold–heat consecutive stress than heat–cold successive stress. Emissions of volatile organic compounds have been enhanced for plants under successive stress when compared with control plants. Chlorophyll concentrations for plants under successive stress decreased for basil and sage plants. The total phenolic and flavonoid contents were not affected by the successive stresses when compared with the plants under only one type of treatment

Green Synthesis, Characterization, and Antibacterial Properties of Silver Nanoparticles Obtained by Using Diverse Varieties of Cannabis sativa Leaf Extracts

Cannabis sativa L. (hemp) is a plant used in the textile industry and green building material industry, as well as for the phytoremediation of soil, medical treatments, and supplementary food products. The synergistic effect of terpenes, flavonoids, and cannabinoids in hemp extracts may mediate the biogenic synthesis of metal nanoparticles. In this study, the chemical composition of aqueous leaf extracts of three varieties of Romanian hemp (two monoecious, and one dioecious) have been determined by Fourier-Transformed Infrared spectroscopy (FT-IR), high-performance liquid chromatography, and mass spectrometry (UHPLC-DAD-MS). Then, their capability to mediate the green synthesis of silver nanoparticles (AgNPs) and their pottential antibacterial applications were evaluated. The average antioxidant capacity of the extracts had 18.4 ± 3.9% inhibition determined by 2,2-diphenyl-1-picrylhydrazyl (DPPH•) and 78.2 ± 4.1% determined by 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS™) assays. The total polyphenolic content of the extracts was 1642 ± 32 mg gallic acid equivalent (GAE) L−1. After this, these extracts were reacted with an aqueous solution of AgNO3 resulting in AgNPs, which were characterized by UV−VIS spectroscopy, FT-IR, scanning electron microscopy (SEM-EDX), and dynamic light scattering (DLS). The results demonstrated obtaining spherical, stable AgNPs with a diameter of less than 69 nm and an absorbance peak at 435 nm. The mixture of extracts and AgNPs showed a superior antioxidant capacity of 2.3 ± 0.4% inhibition determined by the DPPH• assay, 88.5 ± 0.9% inhibition as determined by the ABTS•+ assay, and a good antibacterial activity against several human pathogens: Escherichia coli, Klebsiella pneumoniae, Pseudomonas fluorescens, and Staphylococcus aureus

Camelina sativa Methanolic and Ethanolic Extract Potential in Alleviating Oxidative Stress, Memory Deficits, and Affective Impairments in Stress Exposure-Based Irritable Bowel Syndrome Mouse Models

Camelina sativa is mainly used as an oilseed crop; its edible oil is being also used as a traditional home remedy for the treatment of ulcers, wounds, and eye inflammations, due to the antioxidant activities. In the present study, the chemically characterized alcoholic extracts of Camelina sativa var. Madalina defatted seeds (5 g/kg body weight p.o., suspended in CMC-Na 0.1%) were administered to stress-induced animal models of irritable bowel syndrome (based on combinations of contention stress and multifactorial stress and maternal stress) and evaluated for the behavioural (short-term memory by the Y maze test, the anxious behaviour using the elevated plus maze test, and the antidepressant effect using the forced swimming test) and brain and bowel tissue oxidative status (superoxide dismutase and glutathione peroxidase enzymes activities and malondialdehyde and total soluble protein levels) improving effects. According to the chemical characterization, the extracts were rich in sinapine, glucosinolates, and flavonol glycosides. Moreover, this study showed the beneficial effects of Camelina sativa seed methanolic and ethanolic extracts on the behaviour and brain and bowel tissues oxidative stress status of stress exposure-based IBS mouse models. Despite the slight differences in the chemical composition of the methanolic and ethanolic extracts, the results suggested that the Camelina sativa extracts could reverse the short-term memory impairments caused by stress exposure and also could decrease the intensity and frequency of the anxiety and depressive-like behaviours observed in the stress-exposed animal models of IBS. Furthermore, the Camelina sativa extracts showed a significant effect on the oxidative stress markers in the brain and bowel tissues of the studied animal model by decreasing the superoxide dismutase activity and increasing the glutathione peroxidase activity. However, the results suggested that the extracts could also increase lipid peroxidation in bowel tissues. In this way, this study provides additional evidence that the administration of Camelina sativa seed alcoholic extracts could improve cognitive performances and mood and exhibit the antioxidant capacity in both the brain and bowel tissues

A Peptide-based Vector for Efficient Gene Transfer In Vitro and In Vivo

Finding suitable nonviral delivery vehicles for nucleic acid–based therapeutics is a landmark goal in gene therapy. Cell-penetrating peptides (CPPs) are one class of delivery vectors that has been exploited for this purpose. However, since CPPs use endocytosis to enter cells, a large fraction of peptides remain trapped in endosomes. We have previously reported that stearylation of amphipathic CPPs, such as transportan 10 (TP10), dramatically increases transfection of oligonucleotides in vitro partially by promoting endosomal escape. Therefore, we aimed to evaluate whether stearyl-TP10 could be used for the delivery of plasmids as well. Our results demonstrate that stearyl-TP10 forms stable nanoparticles with plasmids that efficiently enter different cell-types in a ubiquitous manner, including primary cells, resulting in significantly higher gene expression levels than when using stearyl-Arg9 or unmodified CPPs. In fact, the transfection efficacy of stearyl-TP10 almost reached the levels of Lipofectamine 2000 (LF2000), however, without any of the observed lipofection-associated toxicities. Most importantly, stearyl-TP10/plasmid nanoparticles are nonimmunogenic, mediate efficient gene delivery in vivo, when administrated intramuscularly (i.m.) or intradermally (i.d.) without any associated toxicity in mice

Peptide Synthesis Using Proteases as Catalyst

Proteolytic enzymes (proteases) comprise a group of hydrolases (EC 3.4, NC-IUBMB) which share the common feature of acting on peptide bonds. Proteases are among the best studied enzymes in terms of structure-function relationship (Krowarsch et al., 2005). Proteases, by catalyzing the cleavage of other proteins and even themselves, have an enormous physiological significance, their coding genes representing as much as 2% of the total human genome (Schilling and Overall, 2008).Proteases, together with lipases, represent the most important family of enzymes at industrial level, accounting for well over 50% of the enzyme market (Feijoo-Siota and Villa, 2011). Proteases have been used industrially since the onset of enzyme technology in the first decades of the 20th century; many of the early patents issued for the use of enzymes with commercial purposes were proteases, mostly from plant (papain, bromelain) and animal (trypsin, pepsin) origin. Intended uses were in brewing and in leather and rubber manufacturing (Neidelman, 1991). In the decades that follow many large-scale industrial processes were developed using now mostly microbial proteases. A common feature of them was the degradation of proteins and most relevant areas of applications were the food and beverage (Sumantha et al., 2006), detergent (Maurer 2004), leather (Foroughi et al., 2006) and pharmaceutical sectors (Monteiro de Souza et al., 2015). Acid and neutral proteases are relevant to the food industry for the production of protein hydrolyzates (Nielsen and Olsen, 2002), beer chill-proofing (Monsan et al., 1978), meat tenderization (Ashie et al., 2002) and above all, for cheese production (Kim et al., 2004). Alkaline proteases are of paramount importance for the detergent industry (Sellami-Kamoun et al., 2008) and also in tannery (Varela et al., 1997; Thanikaivelan, 2004) and fish-meal production (Schaffeld et al., 1989; Chalamaiah et al., 2012). These conventional applications are by no means outside of continuous technological development (Monteiro de Souza et al. 2015). This is illustrated by the optimization of detergent enzyme performance under the harsh conditions of laundry at high and low temperatures, which has been a continuous challenge tackled by the construction of subtilisin (alkaline protease) variants by random and site-directed mutagenesis and by directed evolution (Kirk et al., 2002; Jares Contesini et al., 2017). It is also illustrated by the production of chymosin in microbial hosts by recombinant DNA technology and further improvement by protein engineering (Mohanty et al., 1999). Therapeutic application of proteases acting as protein hydrolases goes from conventional digestive-aids and anti-inflammatory agents to more sophisticated uses as trombolytic drugs (i.e. urokinase and tissue plasminogen activator) and more recently for the treatment of haemophilia. A comprehensive review on the therapeutic uses of proteases is suggested for the interested reader (Craik et al., 2011)The potential of hydrolytic enzymes for catalyzing reverse reactions of bond formation has been known for quite some time. However, its technological potential as catalysts for organic synthesis developed in the 1980s (Bornscheuer and Kazlauskas, 1999) paralleling the outburst of biocatalysis in non-conventional (non-aqueous) media (Illanes, 2016).Proteases can not only catalyze the cleavage of peptide bonds but, in a proper reaction medium, they can also catalyze the reaction of peptide bond formation. Proteases are highly stereo- and regiospecific, active under mild reaction conditions, do not require coenzymes and are readily available as commodity enzymes, these properties making them quite attractive catalysts for organic synthesis (Bordusa, 2002; Kumar and Bhalla, 2005). Such reactions will not proceed efficiently in aqueous medium where the hydrolytic potential of the enzyme will prevail, so reaction media at low, and hopefully controlled, water activity is necessary for peptide synthesis. This is a major threat since proteases, different from lipases, are not structurally conditioned to act in such environments. The use of proteases in peptide synthesis is analyzed in depth in section 3.4.Fil: Barberis, Sonia Esther. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Física Aplicada "Dr. Jorge Andrés Zgrablich". Universidad Nacional de San Luis; ArgentinaFil: Adaro, Mauricio Omar. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Física Aplicada "Dr. Jorge Andrés Zgrablich". Universidad Nacional de San Luis; ArgentinaFil: Origone, Anabella Lucía. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Física Aplicada "Dr. Jorge Andrés Zgrablich". Universidad Nacional de San Luis; ArgentinaFil: Bersi, Grisel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Física Aplicada "Dr. Jorge Andrés Zgrablich". Universidad Nacional de San Luis; ArgentinaFil: Guzman, Fanny. Pontificia Universidad Catolica de Valparaiso. Escuela de Ingeniería Bioquímica; ChileFil: Illanes, Andres. Pontificia Universidad Catolica de Valparaiso. Escuela de Ingeniería Bioquímica; Chil