Eliciting a robust immune response at mucosal sites is critical in preventing the entry of mucosal pathogens such as influenza and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). This ...task is challenging to achieve without the inclusion of a strong and safe mucosal adjuvant. Previously, inulin acetate (InAc), a plant-based polymer, is shown to activate toll-like receptor-4 (TLR4) and elicit a robust systemic immune response as a vaccine adjuvant. This study investigates the potential of nanoparticles prepared with InAc (InAc-NPs) as an intranasal vaccine delivery system to generate both mucosal and systemic immune responses. InAc-NPs (∼250 nm in diameter) activated wild-type (WT) macrophages but failed to activate macrophages from TLR4 knockout mice or WT macrophages when pretreated with a TLR4 antagonist (lipopolysaccharide-RS (LPS-RS)), which indicates the selective nature of a InAc-based nanodelivery system as a TLR4 agonist. Intranasal immunization using antigen-loaded InAc-NPs generated ∼65-fold and 19-fold higher serum IgG1 and IgG2a titers against the antigen, respectively, as compared to PLGA-NPs as a delivery system. InAc-NPs have also stimulated the secretion of sIgA at various mucosal sites, including nasal-associated lymphoid tissues (NALTs), lungs, and intestine, and produced a strong memory response indicative of both humoral and cellular immune activation. Overall, by stimulating both systemic and mucosal immunity, InAc-NPs laid a basis for a potential intranasal delivery system for mucosal vaccination.
Data emerging from the past 10 years have consolidated the rationale for investigating the use of aspirin as a chemopreventive agent; however, the mechanisms leading to its anticancer effects are ...still being elucidated. We hypothesized that aspirin's chemopreventive actions may involve cell-cycle regulation through modulation of the levels or activity of cyclin A2/cyclin-dependent kinase-2 (CDK2). In this study, HT-29 and other diverse panel of cancer cells were used to demonstrate that both aspirin and its primary metabolite, salicylic acid, decreased cyclin A2 (CCNA2) and CDK2 protein and mRNA levels. The downregulatory effect of either drugs on cyclin A2 levels was prevented by pretreatment with lactacystin, an inhibitor of proteasomes, suggesting the involvement of 26S proteasomes. In-vitro kinase assays showed that lysates from cells treated with salicylic acid had lower levels of CDK2 activity. Importantly, three independent experiments revealed that salicylic acid directly binds to CDK2. First, inclusion of salicylic acid in naïve cell lysates, or in recombinant CDK2 preparations, increased the ability of the anti-CDK2 antibody to immunoprecipitate CDK2, suggesting that salicylic acid may directly bind and alter its conformation. Second, in 8-anilino-1-naphthalene-sulfonate (ANS)-CDK2 fluorescence assays, preincubation of CDK2 with salicylic acid dose-dependently quenched the fluorescence due to ANS. Third, computational analysis using molecular docking studies identified Asp145 and Lys33 as the potential sites of salicylic acid interactions with CDK2. These results demonstrate that aspirin and salicylic acid downregulate cyclin A2/CDK2 proteins in multiple cancer cell lines, suggesting a novel target and mechanism of action in chemoprevention.
Biochemical and structural studies indicate that the antiproliferative actions of aspirin are mediated through cyclin A2/CDK2.
Skin is an important site for local or systemic application of drugs. However, a majority of drugs have poor permeability through the skin’s topmost layer, stratum corneum (SC). The aim of this study ...was to identify safe and smaller peptides that could enhance the skin penetration of drug molecules. By screening phage display peptide library, we have identified a T2 peptide (LVGVFH), which enhanced the penetration of bacteriophages (∼800 nm long bacterial viruses) across porcine and mouse skin. Pretreating the skin with synthetic T2 peptide at pH 4.5 resulted in significant penetration enhancement of hydrophilic drug 5-fluorouracil (5-FU) across skin. FTIR spectroscopy showed that the T2 peptide interacted with skin lipids to enhance the skin penetration. Pretreating the skin with T2 peptide enhanced the partitioning of small molecules with different lipophilicities (5-FU, fluorescein isothiocyanate, and rhodamine 123 hydrochloride) into skin. Fluorescence studies showed that T2 peptide enhanced the diffusion of these molecules into intercellular lipids of SC and thus enhanced the penetration into the skin. Histidine at the c-terminus of T2 peptide was identified to be critical for the skin penetration enhancement. T2 peptide interacted with skin lipids to cause skin penetration enhancement. The study identified a novel, safe, and noninvasive peptide to improve the skin penetration of drugs without chemical conjugation.
Flavonoids have emerged as promising compounds capable of preventing colorectal cancer (CRC) due to their anti-oxidant and anti-inflammatory properties. It is hypothesized that the metabolites of ...flavonoids are primarily responsible for the observed anti-cancer effects owing to the unstable nature of the parent compounds and their degradation by colonic microflora. In this study, we investigated the ability of one metabolite, 2,4,6-trihydroxybenzoic acid (2,4,6-THBA) to inhibit Cyclin Dependent Kinase (CDK) activity and cancer cell proliferation. Using in vitro kinase assays, we demonstrated that 2,4,6-THBA dose-dependently inhibited CDKs 1, 2 and 4 and in silico studies identified key amino acids involved in these interactions. Interestingly, no significant CDK inhibition was observed with the structurally related compounds 3,4,5-trihydroxybenzoic acid (3,4,5-THBA) and phloroglucinol, suggesting that orientation of the functional groups and specific amino acid interactions may play a role in inhibition. We showed that cellular uptake of 2,4,6-THBA required the expression of functional SLC5A8, a monocarboxylic acid transporter. Consistent with this, in cells expressing functional SLC5A8, 2,4,6-THBA induced CDK inhibitory proteins p21
and p27
and inhibited cell proliferation. These findings, for the first time, suggest that the flavonoid metabolite 2,4,6-THBA may mediate its effects through a CDK- and SLC5A8-dependent pathway contributing to the prevention of CRC.
Inflammatory bowel disease (IBD) is a chronic gut disorder that also elevates the risk of colorectal cancer (CRC). The global incidence and severity of IBD are rising, yet existing therapies often ...lead to severe side effects. Curcumin offers potent anti-inflammatory and chemotherapeutic properties. However, its clinical translation is hindered by rapid metabolism, as well as poor water solubility and stability, which limits its bioavailability. To address these challenges, we developed OC-S, a water-soluble and colon-targeted curcumin formulation that protects against colitis in mice. The current study advances OC-S as a dietary supplement by establishing its stability and compatibility with various commercial dietary products. Further, OC-S exhibited specific binding to inflamed colon tissue, potentially aiding in targeted drug retention at the inflammation site in colitis with diarrhea symptoms. We further investigated its efficacy in vivo and in vitro using a murine model of colitis and tumoroids from APCsup.min mice. OC-S significantly reduced colitis severity and pro-inflammatory cytokine expression compared with curcumin, even at very low doses (5 mg/kg/day). It also demonstrated higher anti-proliferative activity in CRC cells and colon cancer tumoroids vs. curcumin. Overall, this study demonstrated that OC-S effectively targets and retains water-soluble curcumin at the inflamed colon sites, while showing promise in addressing both colitis and colorectal cancer, which potentially paves the way for OC-S to advance into clinical development as a dietary product for both IBD and CRC.
S-Nitrosothiol Depletion in Amyotrophic Lateral Sclerosis Schonhoff, Christopher M.; Matsuoka, Masaaki; Tummala, Hemachand ...
Proceedings of the National Academy of Sciences - PNAS,
02/2006, Letnik:
103, Številka:
7
Journal Article
Recenzirano
Odprti dostop
Recent data suggest that either excessive or deficient levels of protein S-nitrosylation may contribute to disease. Disruption of S-nitrosothiol (SNO) homeostasis may result not only from altered ...nitric oxide (NO) synthase activity but also from alterations in the activity of denitrosylases that remove NO groups. A subset of patients with familial amyotrophic lateral sclerosis (ALS) have mutations in superoxide dismutase 1 (SOD1) that increase the denitrosylase activity of SOD1. Here, we show that the increased denitrosylase activity of SOD1 mutants leads to an aberrant decrease in intracellular protein and peptide S-nitrosylation in cell and animal models of ALS. Deficient S-nitrosylation is particularly prominent in the mitochondria of cells expressing SOD1 mutants. Our results suggest that SNO depletion disrupts the function and/or subcellular localization of proteins that are regulated by S-nitrosylation such as glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and thereby contributes to ALS pathogenesis. Repletion of intracellular SNO levels with SNO donor compounds rescues cells from mutant SOD1-induced death. These results suggest that aberrant depletion of intracellular SNOs contributes to motor neuron death in ALS, and raises the possibility that deficient S-nitrosylation is a general mechanism of disease pathogenesis. SNO donor compounds may provide new therapeutic options for diseases such as ALS that are associated with deficient S-nitrosylation.
The goal of the present study is to develop a potent and safe vaccine adjuvant that can also stabilize vaccine formulations during lyophilization and storage. Inulin is a safe plant polysaccharide, ...and in its water soluble isoform, it is known to stabilize protein formulations during storage. However, soluble inulins have never been shown to stimulate the immune system. In this study, for the first time, we showed that water soluble inulins could be developed into vaccine adjuvants by formulating as antigen encapsulated microparticles. A method was developed to prepare soluble inulin microparticles (sIMs) with high encapsulation efficiency (∼75%) and loading (∼75 μg/mg) of the antigen. When immunized in mice, sIMs have generated robust Th2-type antibody titers (IgG1: 500,000) compared to unadjuvanted antigens (IgG1: 17,500) or alum adjuvanted antigens (IgG1: 80,000). In vitro assays showed that a higher proportion of antigen presenting cells (APC’s) have taken up the antigen when presented in sIMs versus in solution (99 % vs 22 %). In addition, the amount of antigen taken up per cell has also been enhanced by more than 25 times when antigen was presented in sIMs. Efficient uptake of the antigen by APCs through sIMS was attributed to the observed enhancement in the immune response by antigen loaded sIMs. The sIMs neither caused any granuloma/tissue damage at the injection site in mice nor were they toxic to the APC’s in cell culture. In conclusion, the current study has developed a safe, soluble inulin based vaccine adjuvant and delivery system.
Evaluating Student Performance and Perception of a Workshop Integrating Pharmacy Practice and a Pharmaceutics Lab.
Common methods for curricular integration are often time and faculty-intensive. An ...innovative approach to integration was developed and utilized in an introductory compounding workshop. Faculty members collaborated with a compounding pharmacist to design and facilitate a pharmaceutics workshop for first-year pharmacy students. The workshop was composed of four major sections, an introduction to pharmaceutical compounding and the regulations surrounding manufacturing and sterility, a case discussion involving a pediatric patient and the need to develop an appropriate drug delivery system, a short review of pharmaceutical calculations and labeling requirements, and then an introduction to logistics and active learning in a lab setting.
After taking part in the workshop, students indicated a significantly higher comfort level going into the pharmaceutics lab (3.48±0.83 to 4.04±0.70) and in the compounding process (3.06±0.83 to 3.71±0.80). Their views of the clinical application of the lab and the need to use knowledge gained from other courses in the lab were also significantly improved (4.36±0.68 to 4.61±0.49 and 3.71±0.77 to 4.26±0.74, respectively). In addition, their perceptions of how they will utilize the skills developed as a practicing pharmacist, and their feelings towards the safety procedures involved in compounding, were also positively affected (3.96±0.87 to 4.45±0.59 and 3.28±0.92 to 3.91±0.72, respectively). Finally, students' average quiz score in Spring 2016, when the workshop was instituted, significantly increased from Spring 2015 (90.154±4.98 versus 85.89±10.87, respectively).
Cancer metastasis is the major cause of cancer mortality. Despite extensive research efforts, effective treatment for cancer metastasis is still lacking. Cancer metastasis involves 4 essential steps: ...cell detachment, migration, invasion, and adhesion. Detachment is the first and required step for metastasis. Glutathione disulfide (GSSG) is derived from the oxidation of glutathione (GSH), which is present in biological systems in millimolar concentration. Although GSSG is commercially available, the impact of GSSG on cell functions/dysfunctions has not been fully explored due to the fact that GSSG is not cell membrane permeable and a lack of method to specifically increase GSSG in cells. We have developed GSSG liposomes that effectively deliver GSSG to cells. Unexpectedly, cells treated with GSSG liposomes were resistant to detachment by trypsinization. This observation led to the investigation of the antimetastatic effect of GSSG liposomes. Our data demonstrate that GSSG liposomes at 1 mg/mL completely blocked cell detachment and migration, and significantly inhibited cancer cell invasion. Aqueous GSSG showed no such effect, confirming that the effects on cell detachment, migration, and invasion were caused by the intracellular delivery of GSSG. An in vivo experiment with a murine melanoma experimental metastasis model showed that GSSG liposomes prevented melanoma lung metastasis. The unique antimetastatic mechanism through the effects on detachment and migration, and effective in vitro and in vivo metastasis inhibition, warrants further investigation of the GSSG liposomes as a potential treatment for cancer metastasis.
New and improved vaccines are needed against challenging diseases such as malaria, tuberculosis, Ebola, influenza, AIDS, and cancer. The majority of existing vaccine adjuvants lack the ability to ...significantly stimulate the cellular immune response, which is required to prevent the aforementioned diseases. This study designed a novel particulate based pathogen-mimicking vaccine delivery system (PMVDS) to target antigen-presenting-cells (APCs) such as dendritic cells. The uniqueness of PMVDS is that the polymer used to prepare the delivery system, Inulin Acetate (InAc), activates the innate immune system. InAc was synthesized from the plant polysaccharide, inulin. PMVDS provided improved and persistent antigen delivery to APCs as an efficient vaccine delivery system, and simultaneously, activated Toll-Like Receptor-4 (TLR-4) on APCs to release chemokine's/cytokines as an immune-adjuvant. Through this dual mechanism, PMVDS robustly stimulated both the humoral (>32 times of IgG1 levels vs alum) and the cell-mediated immune responses against the encapsulated antigen (ovalbumin) in mice. More importantly, PMVDS stimulated both cytotoxic T cells and natural killer cells of cell-mediated immunity to provide tumor (B16-ova-Melanoma) protection in around 40% of vaccinated mice and significantly delayed tumor progression in rest of the mice. PMVDS is a unique bio-active vaccine delivery technology with broader applications for vaccines against cancer and several intracellular pathogens, where both humoral and cellular immune responses are desired.
The PMVDS is a pathogen-mimicking, immune-active (TLR-4 agonist) vaccine delivery system that provides strong antibody and cell-mediated immune responses against encapsulated antigens for efficient cancer immunotherapy. Display omitted
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