Polymers as enhancers of photodynamic activity of chlorin photosensitizers for photodynamic therapy

2013 ◽  
Vol 2 (3) ◽  
Author(s):  
Nadezhda A. Aksenova ◽  
Timur M. Zhientaev ◽  
Anna A. Brilkina ◽  
Ljubov V. Dubasova ◽  
Andrey V. Ivanov ◽  
...  
Keyword(s):  
Photodynamic Therapy ◽  
Dosage Form ◽  
Considerable Increase ◽  
Model Reaction ◽  
Water Soluble ◽  
Effective Dosage ◽  
Polymer Systems ◽  
Photodynamic Activity ◽  
Polymer Interactions ◽  
The Impact

Abstract:The impact of water-soluble and amphiphilic polymers with different structures, namely carboxymethyl cellulose (CMC), polyvinyl alcohol (PVA) and polyvinylpyrrolidone (PVP), was studied on the photoactivity of chlorin photosensitizers (PSs) in photodynamic therapy (PDT). It was shown that such polymers can cause a considerable increase in the PS activity, both in the process of singlet oxygen photogeneration in cell experiments, and in the model reaction of a substrate photooxidation in water. Amongst the studied polymers, CMC and PVP appeared to have the most significant influence on the photoactivity of PSs. The observed effect of the polymers on the photosensitizing activity of PSs can be attributed to the presence of chlorin-polymer interactions resulting in the porphyrin disaggregation in aqueous phase. The effect of the polymers on the photocytotoxicity of PSs is attributed to the absence of interactions between chlorin and polypeptide or lipoproteins which results in a decrease of the photoactivity of chlorins in cell culture. The PS/polymer systems appear to be a new effective dosage form of PDT drugs.

scholarly journals Effect of Chitosan on the Activity of Water-Soluble and Hydrophobic Porphyrin Photosensitizers Solubilized by Amphiphilic Polymers

Polymers ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 1007
Author(s):  
Valeriya V. Kardumyan ◽  
Nadejda A. Aksenova ◽  
Victoria A. Timofeeva ◽  
Alexey V. Krivandin ◽  
Olga V. Shatalova ◽  
...  
Keyword(s):  
Inhibitory Effect ◽  
Amphiphilic Polymers ◽  
Model Reaction ◽  
Amphiphilic Polymer ◽  
Water Soluble ◽  
Pluronic F127 ◽  
Polymer Systems ◽  
Photo Oxidation ◽  
Porphyrin Photosensitizers ◽  
Trisodium Salt

In this work, we studied the photocatalytic activity of photosensitizers (PSs) of various natures solubilized with polyvinylpyrrolidone (PVP) and ternary block copolymer ethylene and propylene oxide Pluronic F127 (F127) in a model reaction of tryptophan photo-oxidation in water in the presence of chitosan (CT). Water-soluble compounds (dimegin and trisodium salt of chlorin e6 (Ce6)) and hydrophobic porphyrins (tetraphenylporphyrin (TPP) and its fluorine derivative (TPPF20)) were used as PSs. It was shown that the use of chitosan (Mw ~100 kDa) makes it possible to obtain a system whose activity is comparable to that of the photosensitizer-amphiphilic polymer systems. Thus, the previously observed drop in the photosensitizing activity of PS in the presence of a polysaccharide and amphiphilic polymers (AP) was absent in this case. At the same time, chitosan had practically no inhibitory effect on hydrophobic porphyrins solubilized by Pluronic F127.

Water-soluble conjugated polymer with near-infrared absorption for synergistic tumor therapy using photothermal and photodynamic activity

2019 ◽  
Vol 55 (59) ◽  
pp. 8615-8618 ◽  
Author(s):  
Sirong Zhou ◽  
Changgang Yang ◽  
Lixia Guo ◽  
Yunxia Wang ◽  
Guofeng Zhang ◽  
...  
Keyword(s):  
Photodynamic Therapy ◽  
Infrared Absorption ◽  
Conjugated Polymer ◽  
Near Infrared ◽  
Tumor Therapy ◽  
Water Soluble ◽  
Nir Light ◽  
Photodynamic Activity

A novel NIR-absorbing and water-soluble conjugated polymer (PTDBD) for single-NIR-light induced synergetic photothermal/photodynamic therapy was developed.

Genetic Variation: Impact on Folate (and Choline) Bioefficacy

2010 ◽  
Vol 80 (45) ◽  
pp. 319-329 ◽  
Author(s):  
Allyson A. West ◽  
Marie A. Caudill
Keyword(s):  
Carbon Metabolism ◽  
Genetic Variants ◽  
Plasma Homocysteine ◽  
Water Soluble ◽  
Gene Interactions ◽  
Dietary Folate ◽  
Methyl Donors ◽  
Common Genetic Variants ◽  
One Carbon Metabolism ◽  
The Impact

Folate and choline are water-soluble micronutrients that serve as methyl donors in the conversion of homocysteine to methionine. Inadequacy of these nutrients can disturb one-carbon metabolism as evidenced by alterations in circulating folate and/or plasma homocysteine. Among common genetic variants that reside in genes regulating folate absorptive and metabolic processes, homozygosity for the MTHFR 677C > T variant has consistently been shown to have robust effects on status markers. This paper will review the impact of genetic variants in folate-metabolizing genes on folate and choline bioefficacy. Nutrient-gene and gene-gene interactions will be considered along with the need to account for these genetic variants when updating dietary folate and choline recommendations.

scholarly journals Desiccation time and rainfall control gaseous carbon fluxes in an intermittent stream

2021 ◽  
Author(s):  
Maria Isabel Arce ◽  
Mia M. Bengtsson ◽  
Daniel von Schiller ◽  
Dominik Zak ◽  
Jana Täumer ◽  
...  
Keyword(s):  
Water Soluble ◽  
Intermittent Flow ◽  
Dry Period ◽  
Intermittent Stream ◽  
Aerobic Activity ◽  
Water Soluble Organic Carbon ◽  
Soluble Organic Carbon ◽  
Microbial C ◽  
Global Biogeochemical Cycles ◽  
The Impact

AbstractDroughts are recognized to impact global biogeochemical cycles. However, the implication of desiccation on in-stream carbon (C) cycling is not well understood yet. We subjected sediments from a lowland, organic rich intermittent stream to experimental desiccation over a 9-week-period to investigate temporal changes in microbial functional traits in relation to their redox requirements, carbon dioxide (CO2) and methane (CH4) fluxes and water-soluble organic carbon (WSOC). Concurrently, the implications of rewetting by simulated short rainfalls (4 and 21 mm) on gaseous C fluxes were tested. Early desiccation triggered dynamic fluxes of CO2 and CH4 with peak values of 383 and 30 mg C m−2 h−1 (mean ± SD), respectively, likely in response to enhanced aerobic mineralization and accelerated evasion. At longer desiccation, CH4 dropped abruptly, likely because of reduced abundance of anaerobic microbial traits. The CO2 fluxes ceased later, suggesting aerobic activity was constrained only by extended desiccation over time. We found that rainfall boosted fluxes of CO2, which were modulated by rainfall size and the preceding desiccation time. Desiccation also reduced the amount of WSOC and the proportion of labile compounds leaching from sediment. It remains questionable to which extent changes of the sediment C pool are influenced by respiration processes, microbial C uptake and cell lysis due to drying-rewetting cycles. We highlight that the severity of the dry period, which is controlled by its duration and the presence of precipitation events, needs detailed consideration to estimate the impact of intermittent flow on global riverine C fluxes.

scholarly journals A non-toxic, reversibly released imaging probe for oral cancer that is derived from natural compounds

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Magda Ghanim ◽  
Nicola Relitti ◽  
Gavin McManus ◽  
Stefania Butini ◽  
Andrea Cappelli ◽  
...  
Keyword(s):  
Oral Cancer ◽  
Cancer Progression ◽  
Intraoperative Imaging ◽  
Critical Role ◽  
Water Soluble ◽  
Stem Cell Marker ◽  
Squamous Cells ◽  
Tissue Identification ◽  
Tumorigenic Potential ◽  
The Impact

AbstractCD44 is emerging as an important receptor biomarker for various cancers. Amongst these is oral cancer, where surgical resection remains an essential mode of treatment. Unfortunately, surgery is frequently associated with permanent disfigurement, malnutrition, and functional comorbidities due to the difficultly of tumour removal. Optical imaging agents that can guide tumour tissue identification represent an attractive approach to minimising the impact of surgery. Here, we report the synthesis of a water-soluble fluorescent probe, namely HA-FA-HEG-OE (compound 1), that comprises components originating from natural sources: oleic acid, ferulic acid and hyaluronic acid. Compound 1 was found to be non-toxic, displayed aggregation induced emission and accumulated intracellularly in vesicles in SCC-9 oral squamous cells. The uptake of 1 was fully reversible over time. Internalization of compound 1 occurs through receptor mediated endocytosis; uniquely mediated through the CD44 receptor. Uptake is related to tumorigenic potential, with non-tumorigenic, dysplastic DOK cells and poorly tumorigenic MCF-7 cells showing only low intracellular levels and highlighting the critical role of endocytosis in cancer progression and metastasis. Together, the recognised importance of CD44 as a cancer stem cell marker in oral cancer, and the reversible, non-toxic nature of 1, makes it a promising agent for real time intraoperative imaging.

Jam processing: Effect of pectin replacement by locust bean gum on its characteristics

2020 ◽  
pp. 1-12
Author(s):  
Aida Mekhoukhe ◽  
Nacer Mohellebi ◽  
Tayeb Mohellebi ◽  
Leila Deflaoui-Abdelfettah ◽  
Sonia Medouni-Adrar ◽  
...  
Keyword(s):  
Cold Water ◽  
Physicochemical Characteristics ◽  
Water Soluble ◽  
Sensory Profile ◽  
Locust Bean Gum ◽  
Locust Bean ◽  
Preference Map ◽  
The Right ◽  
High Level ◽  
The Impact

OBJECTIVE: the present work proposed to extract Locust Bean Gum (LBG) from Algerian carob fruits, evaluate physicochemical and rheological properties (solubility). It aimed also to develop different formulations of strawberry jams with a mixture of LBG and pectin in order to obtain a product with a high sensory acceptance. METHODS: the physicochemical characteristics of LBG were assessed. The impact of temperature on solubility was also studied. The physical and the sensory profile and acceptance of five Jams were evaluated. RESULTS: composition results revealed that LBG presented a high level of carbohydrate but low concentrations of fat and ash. The LBG was partially cold-water-soluble (∼62% at 25°C) and needed heating to reach a higher solubility value (∼89% at 80 °C). Overall, the sensorial acceptances decreased in jams J3 which was formulated with 100% pectin and commercial one (J5). The external preference map explained that most consumers were located to the right side of the map providing evidence that most samples appreciated were J4 and J2 (rate of 80–100%). CONCLUSION: In this investigation, the LBG was used successfully in the strawberry jam’s formulation.

scholarly journals The Correlation between Physical Crosslinking and Water-Soluble Drug Release from Chitosan-Based Microparticles

Pharmaceutics ◽  
2020 ◽  
Vol 12 (5) ◽  
pp. 455
Author(s):  
Emilia Szymańska ◽  
Katarzyna Woś-Latosi ◽  
Julia Jacyna ◽  
Magdalena Dąbrowska ◽  
Joanna Potaś ◽  
...  
Keyword(s):  
Drug Release ◽  
Polymer Matrix ◽  
Drug Loading ◽  
Water Soluble ◽  
Dissolution Behavior ◽  
Complex Nature ◽  
Prolonged Release ◽  
Scanning Calorimetry ◽  
Burst Effect ◽  
The Impact

Microparticles containing water-soluble zidovudine were prepared by spray-drying using chitosan glutamate and beta-glycerophosphate as an ion crosslinker (CF). The Box–Behnken design was applied to optimize the microparticles in terms of their drug loading and release behavior. Physicochemical studies were undertaken to support the results from dissolution tests and to evaluate the impact of the crosslinking ratio on the microparticles’ characteristics. The zidovudine dissolution behavior had a complex nature which comprised two phases: an initial burst effect followed with a prolonged release stage. The initial drug release, which can be modulated by the crosslinking degree, was primarily governed by the dissolution of the drug crystals located on the microparticles’ surfaces. In turn, the further dissolution stage was related to the drug diffusion from the swollen polymer matrix and was found to correlate with the drug loading. Differential Scanning Calorimetry (DSC) studies revealed the partial incorporation of a non-crystallized drug within the polymer matrix, which correlated with the amount of CF. Although CF influenced the swelling capacity of chitosan glutamate microparticles, surprisingly a higher amount of CF did not impact the time required for 80% of the drug to be released markedly. The formulation with the lowest polymer:CF ratio, 3:1, was selected as optimal, providing satisfactory drug loading and displaying a moderate burst effect within the first 30 min of the study, followed with a prolonged drug release of up to 210 min.

scholarly journals An Efficient Photodynamic Therapy Treatment for Human Pancreatic Adenocarcinoma

2020 ◽  
Vol 9 (1) ◽  
pp. 192 ◽  
Author(s):  
Alexandre Quilbe ◽  
Olivier Moralès ◽  
Martha Baydoun ◽  
Abhishek Kumar ◽  
Rami Mustapha ◽  
...  
Keyword(s):  
Pancreatic Cancer ◽  
Photodynamic Therapy ◽  
Immune System ◽  
Cancer Cells ◽  
Pancreatic Adenocarcinoma ◽  
Cell Lines ◽  
Folate Receptor ◽  
Mice Model ◽  
Gene And Protein Expression ◽  
The Impact

To date, pancreatic adenocarcinoma (ADKP) is a devastating disease for which the incidence rate is close to the mortality rate. The survival rate has evolved only 2–5% in 45 years, highlighting the failure of current therapies. Otherwise, the use of photodynamic therapy (PDT), based on the use of an adapted photosensitizer (PS) has already proved its worth and has prompted a growing interest in the field of oncology. We have developed a new photosensitizer (PS-FOL/PS2), protected by a recently published patent (WO2019 016397-A1, 24 January 2019). This photosensitizer is associated with an addressing molecule (folic acid) targeting the folate receptor 1 (FOLR1) with a high affinity. Folate binds to FOLR1, in a specific way, expressed in 100% of ADKP or over-expressed in 30% of cases. The first objective of this study is to evaluate the effectiveness of this PS2-PDT in four ADKP cell lines: Capan-1, Capan-2, MiapaCa-2, and Panc-1. For this purpose, we first evaluated the gene and protein expression of FOLR1 on four ADKP cell lines. Subsequently, we evaluated PS2’s efficacy in our cell lines and we assessed the impact of PDT on the secretome of cancer cells and its impact on the immune system. Finally, we evaluate the PDT efficacy on a humanized SCID mouse model of pancreatic cancer. In a very interesting way, we observed a significant increase in the proliferation of activated-human PBMC when cultured with conditioned media of ADKP cancer cells subjected to PDT. Furthermore, to evaluate in vivo the impact of this new PS, we analyzed the tumor growth in a humanized SCID mice model of pancreatic cancer. Four conditions were tested: Untreated, mice (nontreated), mice with PS (PS2), mice subjected to illumination (Light only), and mice subjected to illumination in the presence of PS (PDT). We noticed that the mice subjected to PDT presented a strong decrease in the growth of the tumor over time after illumination. Our investigations have not only suggested that PS2-PDT is an effective therapy in the treatment of PDAC but also that it activates the immune system and could be considered as a real adjuvant for anti-cancer vaccination. Thus, this new study provides new treatment options for patients in a therapeutic impasse and will provide a new arsenal in the fight against PDAC.

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