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1.
J Nanobiotechnology ; 22(1): 409, 2024 Jul 11.
Article in English | MEDLINE | ID: mdl-38992688

ABSTRACT

OBJECTIVE: This study aimed to investigate the critical role of MDSCs in CRC immune suppression, focusing on the CSF1R and JAK/STAT3 signaling axis. Additionally, it assessed the therapeutic efficacy of LNCs@CSF1R siRNA and anti-PD-1 in combination. METHODS: Single-cell transcriptome sequencing data from CRC and adjacent normal tissues identified MDSC-related differentially expressed genes. RNA-seq analysis comprehensively profiled MDSC gene expression in murine CRC tumors. LNCs@CSF1R siRNA nanocarriers effectively targeted and inhibited CSF1R. Flow cytometry quantified changes in MDSC surface markers post-CSF1R inhibition. RNA-seq and pathway enrichment analyses revealed the impact of CSF1R on MDSC metabolism and signaling. The effect of CSF1R inhibition on the JAK/STAT3 signaling axis was validated using Colivelin and metabolic assessments. Glucose and fatty acid uptake were measured via fluorescence-based flow cytometry. The efficacy of LNCs@CSF1R siRNA and anti-PD-1, alone and in combination, was evaluated in a murine CRC model with extensive tumor section analyses. RESULTS: CSF1R played a significant role in MDSC-mediated immune suppression. LNCs@CSF1R siRNA nanocarriers effectively targeted MDSCs and inhibited CSF1R. CSF1R regulated MDSC fatty acid metabolism and immune suppression through the JAK/STAT3 signaling axis. Inhibition of CSF1R reduced STAT3 activation and target gene expression, which was rescued by Colivelin. Combined treatment with LNCs@CSF1R siRNA and anti-PD-1 significantly slowed tumor growth and reduced MDSC abundance within CRC tumors. CONCLUSION: CSF1R via the JAK/STAT3 axis critically regulates MDSCs, particularly in fatty acid metabolism and immune suppression. Combined therapy with LNCs@CSF1R siRNA and anti-PD-1 enhances therapeutic efficacy in a murine CRC model, providing a strong foundation for future clinical applications.


Subject(s)
Colorectal Neoplasms , Myeloid-Derived Suppressor Cells , RNA, Small Interfering , Receptors, Granulocyte-Macrophage Colony-Stimulating Factor , STAT3 Transcription Factor , Animals , Myeloid-Derived Suppressor Cells/metabolism , Mice , Colorectal Neoplasms/drug therapy , Colorectal Neoplasms/immunology , Receptors, Granulocyte-Macrophage Colony-Stimulating Factor/antagonists & inhibitors , Receptors, Granulocyte-Macrophage Colony-Stimulating Factor/metabolism , STAT3 Transcription Factor/metabolism , Cell Line, Tumor , Humans , Signal Transduction/drug effects , Programmed Cell Death 1 Receptor/metabolism , Female , Mice, Inbred BALB C , Janus Kinases/metabolism , Immunomodulation/drug effects , Receptor, Macrophage Colony-Stimulating Factor
2.
Article in English | MEDLINE | ID: mdl-36508590

ABSTRACT

The current assessment estimated exposure to four low- and no-calorie sweeteners (LNCS) (aspartame, acesulfame potassium (AceK), steviol glycosides and sucralose) from beverages in Brazil, Canada, Mexico and the United States, using up-to-date nationally representative consumption data and industry reported-use level information. Two modelling scenarios were applied - the probabilistic model was guided by reported use level data, with estimated intake for an individual leveraging market-weighted average use level of a particular LNCS in any given LNCS-sweetened beverage type, while the distributional (brand-loyal) model assumed consumer behaviour-led patterns, namely that an individual will be brand loyal to a pre-determined beverage type. Consumer-only and general population intake estimates were derived for the overall population and individual age categories, and compared to the respective acceptable daily intake (ADI) as established by the Joint FAO/WHO Expert Committee on Food Additives (JECFA) for each LNCS. The mean, 90th percentile and 95th percentile intake estimates were substantially lower than the ADI in both modelling scenarios, regardless of the population group or market. In the probabilistic model, the highest consumer-only intake was observed for AceK in Brazilian adolescents (95th percentile, 12.4% of the ADI), while the highest 95th percentile intakes in the distributional model were observed for sucralose in Canadian adults at 20.9% of the ADI. This study provides the latest insights into current intakes of LNCS from water-based non-alcoholic LNCS-sweetened beverages in these regions, aligning well with those published elsewhere.


Subject(s)
Beverages , Sweetening Agents , Adult , Adolescent , Humans , United States , Brazil , Mexico , Canada
3.
Int J Pharm ; 629: 122375, 2022 Dec 15.
Article in English | MEDLINE | ID: mdl-36351506

ABSTRACT

Luteolin is an excellent flavone possessing several beneficial properties such as antioxidant and anti-inflammatory effects which are interesting for skin delivery. Development of an appropriate skin delivery system could be a promising strategy to improve luteolin cutaneous performance.So, the main aim of this work was to fabricate, characterize and evaluate phospholipid-based luteolin-loaded lipid nanocapsules for skin delivery. The influence of phospholipid/oil ratio, surfactant type and chitosan coating were investigated. The prepared formulations underwent in vitro assessment and the selected formulations were evaluated ex vivo and in vivo. The mean diameters of investigated formulations varied between 174 nm and 628 nm while zeta potential varied between -25.7 ± 4.8 mV and 6.8 ± 1.7 mV. Increasing in phospholipid/oil ratios resulted in decrease in particles size with little effect on zeta potential and drug encapsulation. Cremophor EL showed the lowest particle sizes and the highest drug encapsulation. Chitosan coating shifted zeta potential towards positive values. Structural analyses showed that luteolin is incorporated into lipid core of nanocapsules. Selected formulations (LNC4 and LNC13) exhibited sustained in vitro release and antioxidant activity. LNC13 (chitosan coated) showed higher flux (0.457 ± 0.113 µg/cm2/h), permeability (45.70 ± 11.66 *10-5 cm2/h) and skin retention (121.66 ± 7.6 µg/cm2 after 24 h) when compared to LNC4 and suspension. It also showed disordered the integrity of the stratum corneum, increased epidermal thickness and relieving most of inflammatory features in animal model. In conclusion, this study proves that lipid nanocapsules could effectively deliver luteolin into skin and then can be established as a potential system in the pharmaceutical and cosmeceutical horizons.


Subject(s)
Chitosan , Nanocapsules , Animals , Nanocapsules/chemistry , Phospholipids/chemistry , Chitosan/chemistry , Luteolin/pharmacology , Skin , Particle Size
4.
Int J Pharm X ; 4: 100127, 2022 Dec.
Article in English | MEDLINE | ID: mdl-36177093

ABSTRACT

Several studies previously showed that the NFL-TBS.40-63 peptide (NFL-peptide) is capable to specifically penetrating several glioblastoma cell lines (rat, mouse, human) and inhibiting their cell division in vitro and their tumor development in vivo. When lipid nanocapsules (LNCs) are functionalized with the NFL-peptide, their absorption is targeted in glioblastoma cells both in vitro and in vivo. In the present study, we investigated the molecular architecture of these nanovectors (LNC-NFL) by using several microscopy techniques (transmission electron microscopy, cryo-electron microscopy, and cryo-electron tomography). We also used high-performance liquid chromatography (UPLC) technique to evaluate the interaction between LNCs and peptides. The work shows that the NFL-peptide forms stable long filaments along which the lipid nanocapsules interact strongly to form some sort of nanomolecular bracelets. This new construction composed of the NFL-peptide and lipid nanocapsules shows a better internalization in rat glioblastoma cells (F98 cells) than lipid nanocapsules alone.

5.
Article in English | MEDLINE | ID: mdl-35020577

ABSTRACT

This research examined the intakes of six low- and no-calorie sweeteners (LNCS) (acesulfame-K, aspartame, cyclamate, saccharin, steviol glycosides, and sucralose) by the Brazilian population using an added sugar substitution approach. Detailed exposure modelling requires the use of proprietary concentration data, which can be difficult to obtain. Two exposure models were conducted using nationally representative food consumption data. The first model ('per person') estimated added sugar intakes on an individual person basis, replacing 50% of added sugar intakes >10% total energy with each LNCS considering sucrose sweetness equivalence. The second model ('per food') replaced 50% of the added sugar content in foods and beverages with each LNCS, incorporating sucrose sweetness equivalence and Brazilian tonnage data. Both models predicted that intakes would be below the JECFA ADI for five of the six LNCS in all population groups examined (≥10 years) for average and heavy consumers. For cyclamate, exceedance of the ADI was determined for all age groups amongst heavy consumers in the 'per person' model, while estimated intakes in the 'per food' model were below or reached the ADI for the cohort. Additional research is needed for younger age groups to confirm whether these findings are applicable to the entire Brazilian population.


Subject(s)
Beverages/analysis , Food Analysis , Sweetening Agents/analysis , Adolescent , Adult , Brazil , Child , Humans , Middle Aged , Sweetening Agents/administration & dosage , Young Adult
6.
Article in English | MEDLINE | ID: mdl-34461023

ABSTRACT

As obesity rates increase, several countries in Latin America have implemented strategies to curb the consumption of sugars, resulting in reformulations of products with low and no-calorie sweeteners (LNCS). The increased availability of LNCS-containing products raises concerns about the potential risk of exceeding the Acceptable Daily Intake (ADI). Information on the intake of LNCS among Latin American countries are limited by the lack of publicly available national consumption data. Using the Budget Method, screening level intake estimates of six LNCS (acesulfame potassium, aspartame, cyclamate, saccharin, steviol glycosides, and sucralose) were derived for Argentina, Chile, and Peru based on national sales data and product labels. Four tiered assessments were conducted where assumption of LNCS use ranged from the most conservative Tier 1 to the more refined yet conservative LNCS use and concentrations in subsequent tiers. The estimated intakes, applicable to the total population as well as children, were below their ADIs for all tiers. For Tier 2 where average LNCS concentrations were assumed present in all LNCS-containing products, intakes were <60% of the ADI. Estimates for the more refined tiers were comparable to published estimates based on select subpopulations in these countries, validating the approach used in this study.


Subject(s)
Beverages/analysis , Food Analysis , Sweetening Agents/analysis , Argentina , Chile , Energy Intake , Humans , No-Observed-Adverse-Effect Level , Peru
7.
Acta Pharm Sin B ; 11(1): 55-70, 2021 Jan.
Article in English | MEDLINE | ID: mdl-33532180

ABSTRACT

Cancer stem cells (CSCs) are a subpopulation of cancer cells with functions similar to those of normal stem cells. Although few in number, they are capable of self-renewal, unlimited proliferation, and multi-directional differentiation potential. In addition, CSCs have the ability to escape immune surveillance. Thus, they play an important role in the occurrence and development of tumors, and they are closely related to tumor invasion, metastasis, drug resistance, and recurrence after treatment. Therefore, specific targeting of CSCs may improve the efficiency of cancer therapy. A series of corresponding promising therapeutic strategies based on CSC targeting, such as the targeting of CSC niche, CSC signaling pathways, and CSC mitochondria, are currently under development. Given the rapid progression in this field and nanotechnology, drug delivery systems (DDSs) for CSC targeting are increasingly being developed. In this review, we summarize the advances in CSC-targeted DDSs. Furthermore, we highlight the latest developmental trends through the main line of CSC occurrence and development process; some considerations about the rationale, advantages, and limitations of different DDSs for CSC-targeted therapies were discussed.

8.
Article in English | MEDLINE | ID: mdl-33451265

ABSTRACT

A tiered intake assessment approach is presented and applied to derive the maximum potential global low- and no-calorie sweeteners (LNCS) intake estimates. The US and Uk markets served as representative for the world and the EU region, respectively, to determine the maximum potential exposure for acesulfame potassium (AceK), aspartame, saccharin, steviol glycosides, and sucralose in various subpopulations, including brand-loyal consumers. Conservative intake estimates for LNCS used in non-alcoholic beverages were calculated for the general population 2 + y, toddlers (12-35 months (US) or 18-35 months (UK)), young children 3-9 y, adolescents 10-17 y, adults 18-64 y, elderly 65-74 y, and very elderly 75 + y based on assumed uses in high beverage consumption markets, leveraging either the 2-day food consumption data from the 2013-2016 US National Health and Nutrition Examination Survey or the 4-day food consumption data from the 2008-2017 UK National Diet and Nutrition Survey Rolling Programme. Strong concordance between the refined budget method and the brand-loyal deterministic approach was shown, the latter assumes the maximum industry-reported global LNCS use level is present in 100% of non-alcoholic beverages. This study shows that safety of LNCS in beverages at proposed use levels can be supported for any geography, with all intake estimates falling below the acceptable daily intake in refined assessments. Importantly, this study shows the refined budget method to be a valid first-tier screening assessment in prioritising those LNCS that may benefit from more refined intake assessments when warranted.


Subject(s)
Beverages/analysis , Energy Intake , Food Analysis , Food Contamination/analysis , Sweetening Agents/analysis , Adolescent , Adult , Aged , Child , Child, Preschool , Female , Humans , Infant , Male , Middle Aged , No-Observed-Adverse-Effect Level , Nutrition Surveys , Young Adult
9.
Article in English | MEDLINE | ID: mdl-33337974

ABSTRACT

Estimated intake of six low and no-calorie sweeteners (LNCS) (acesulfame potassium, aspartame, cyclamate, saccharin, steviol glycosides and sucralose) from processed foods and beverages, as well as from tabletop sweeteners uses, by the Brazilian population were derived and compared to the respective Acceptable Daily Intake (ADI). The estimates were based on dietary consumption data from a nationwide cross-sectional survey conducted by the Instituto Brasileiro de Geografia e Estatística (IBGE) in 2008-2009 and LNCS use rates and associated market share information based on data provided by Brazilian industry members. Two intake scenarios were considered: a conservative brand loyal consumer scenario that assumes all LNCS-containing foods and beverages and tabletop sweeteners contain the maximum reported LNCS concentrations (Scenario A) and a scenario representative of the general consumer population that uses a market share weighted average of the reported concentrations (Scenario B). Intake estimates were derived for the total Brazilian population (age 10 + y), and for the subpopulations of adolescents (10-18y), adults (19-59y), and older adults (60 + y). Intake of LNCS up to the 95th percentile did not exceed their respective ADI for all subpopulations considered, in either the general consumer scenario or the brand loyal scenario. Among consumers age 10 + y, the 95th percentile intakes of the various LNCS ranged from 6.8% to 54% of their respective ADI for the brand loyal scenario and from <1% to 6.0% of their respective ADIs for the general consumer scenario.


Subject(s)
Beverages/analysis , Energy Intake , Food Analysis , Food Contamination/analysis , Sweetening Agents/analysis , Adolescent , Adult , Brazil , Child , Female , Humans , Male , Middle Aged , Nutrition Surveys , Young Adult
10.
Colloids Surf B Biointerfaces ; 190: 110927, 2020 Jun.
Article in English | MEDLINE | ID: mdl-32169777

ABSTRACT

Lipid Nanocapsules (LNCs) have been used for drug delivery in cells and animal models for several years. LNCs with unique physicochemical properties for favorable biorecognition, biocompatibility and stimuli responsive (pH/temperature etc.) properties i.e., smart-LNCs, are most promising for future nanomedicine applications. However, conventional phase inversion temperature (PIT) method of LNCs preparation may not be suitable for the fabrication of thermally labile drug loaded LNCs and smart-LNCs. Herein, we report for the first time, a novel low temperature (LT) method for the preparation of LNCs (including smart-LNCs of size 25-150 nm), hereafter, named as nanostructure hybrid lipid capsules (nHLCs), comprising safe excipients such as oil (Labrafac™ PG), surfactant (Kolliphor® HS 15, Brij® S100), and lipid (Lipoid S-75, Lipoid S PC-3, Lipoid PE 18:1/18:1, Lipoid PC 16:0/16:0 etc.). Effects of process parameters on the physicochemical properties of nHLCs were probed to optimize the process. Ternary phase diagram shows that our method allows for great flexibility in the formation of nHLCs with tailored size and composition. This method resulted in drug loaded (regorafenib used as model drug) nHLCs with 95 % encapsulation efficiency and sustained release profile at 37 °C. The drug loaded nHLCs (as prepared or in lyophilized form) has excellent storage stability at 4 °C (for more than one month) as well as biocompatibility similar to that of LNCs prepared by PIT method. Our novel LT method of LNCs (i.e. nHLCs) preparation is a generic method for the development of drug loaded (including thermally labile) and smart-LNCs for future nanomedicine applications.


Subject(s)
Biocompatible Materials/chemistry , Drug Delivery Systems , Lipids/chemistry , Nanostructures/chemistry , Phenylurea Compounds/chemistry , Pyridines/chemistry , Temperature , Capsules/chemistry , Particle Size , Surface Properties
11.
Curr Med Chem ; 27(22): 3623-3656, 2020.
Article in English | MEDLINE | ID: mdl-31232233

ABSTRACT

Colloidal carriers diverge depending on their composition, ability to incorporate drugs and applicability, but the common feature is the small average particle size. Among the carriers with the potential nanostructured drug delivery application there are SLN and NLC. These nanostructured systems consist of complex lipids and highly purified mixtures of glycerides having varying particle size. Also, these systems have shown physical stability, protection capacity of unstable drugs, release control ability, excellent tolerability, possibility of vectorization, and no reported production problems related to large-scale. Several production procedures can be applied to achieve high association efficiency between the bioactive and the carrier, depending on the physicochemical properties of both, as well as on the production procedure applied. The whole set of unique advantages such as enhanced drug loading capacity, prevention of drug expulsion, leads to more flexibility for modulation of drug release and makes Lipid-based nanocarriers (LNCs) versatile delivery system for various routes of administration. The route of administration has a significant impact on the therapeutic outcome of a drug. Thus, the non-invasive routes, which were of minor importance as parts of drug delivery in the past, have assumed added importance drugs, proteins, peptides and biopharmaceuticals drug delivery and these include nasal, buccal, vaginal and transdermal routes. The objective of this paper is to present the state of the art concerning the application of the lipid nanocarriers designated for non-invasive routes of administration. In this manner, this review presents an innovative technological platform to develop nanostructured delivery systems with great versatility of application in non-invasive routes of administration and targeting drug release.


Subject(s)
Nanoparticles , Nanostructures , Administration, Cutaneous , Drug Carriers , Drug Delivery Systems , Lipids , Particle Size
12.
Colloids Surf B Biointerfaces ; 135: 441-447, 2015 Nov 01.
Article in English | MEDLINE | ID: mdl-26280818

ABSTRACT

In this paper, we investigated the potential of lipid nanocapsules (LNCs) as a delivery system of small hydrophobic molecules, polycyclic aromatic hydrocarbons (PAHs) - pyrene, fluoranthene, phenanthrene, in the copepod Acartia tonsa. The LNCs were produced by a phase inversion process with a nominal size of 50 nm. These nanocapsules were obtained without organic solvent and with pharmaceutically acceptable excipients. The PAHs-LNCs displayed a stable monodisperse size distribution and a good stability in sea water for 7 days. By using fluorescent LNCs, it was possible to evidence LNCs ingestion by the copepods using confocal laser scanning microscopy. While blank LNCs are not toxic to copepods at tested concentrations, PAH-loaded LNCs were found to be very toxic on A. tonsa with a high mortality rate reaching 95% after 72 h exposure to 200 nM pyrene-loaded LNCs. On the other hand, when acetone is used to dissolve an equivalent concentration of PAHs in sea water, the copepod mortality is 10 times lower than using LNCs as nano-delivery system. This confirms the efficiency of using LNCs to deliver molecules directly in the gut or copepod carapace. The small size and non toxicity of these delivery nano-systems make them suitable for drug delivery to copepods.


Subject(s)
Copepoda , Lipids/chemistry , Nanocapsules/chemistry , Acetone/chemistry , Animals , Drug Delivery Systems , Drug Stability , Excipients , Lipids/toxicity , Nanocapsules/toxicity , Particle Size , Polycyclic Aromatic Hydrocarbons/administration & dosage , Polycyclic Aromatic Hydrocarbons/toxicity , Reproduction/drug effects , Seawater/chemistry , Toxicity Tests
13.
C R Biol ; 336(9): 425-32, 2013 Sep.
Article in English | MEDLINE | ID: mdl-24161239

ABSTRACT

Plant organs grow in coordinated and continuous way. Such growth is of a tensor nature, hence there is an infinite number of different directions of growth rate in each point of the growing organ. Three mutually orthogonal directions of growth can be recognized in which growth achieves extreme values (principal directions of growth [PDGs]). Models based on the growth tensor have already been successfully applied to the root and shoot apex. This paper presents the 2D model of growth applied to the arabidopsis leaf. The model employs the growth tensor method with a non-stationary velocity field. The postulated velocity functions are confirmed by growth measurements with the aid of the replica method.


Subject(s)
Arabidopsis/growth & development , Computer Simulation , Models, Biological , Plant Leaves/growth & development , Biomechanical Phenomena
14.
J Neuroimmunol ; 262(1-2): 19-26, 2013 Sep 15.
Article in English | MEDLINE | ID: mdl-23768729

ABSTRACT

The pathogenic role of antibodies in multiple sclerosis (MS) is still controversial. We transferred to mice with experimental autoimmune encephalomyelitis (EAE), animal model of MS, IgG antibodies purified from a MS patient presenting a dramatic clinical improvement during relapse after selective IgG removal with immunoadsorption. Passive transfer of patient's IgG exacerbated motor paralysis and increased mouse central nervous system (CNS) inflammation and demyelination. Binding of patient's IgG was demonstrated in mouse CNS, with a diffuse staining of white matter oligodendrocytes. These data support a growing body of evidence that antibodies can play an important role in the pathobiology of MS.


Subject(s)
Central Nervous System/drug effects , Encephalomyelitis, Autoimmune, Experimental/immunology , Encephalomyelitis, Autoimmune, Experimental/pathology , Immunoglobulin G/administration & dosage , Immunosorbents/administration & dosage , Multiple Sclerosis, Relapsing-Remitting/immunology , Adult , Animals , Demyelinating Diseases/chemically induced , Disease Models, Animal , Female , Humans , Immunization, Passive/methods , Immunosorbent Techniques , Mice , Plasma Exchange/methods
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