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1.
J Infect Dis ; 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38990787

RESUMO

BACKGROUND: Paracoccidioidomycosis (PCM), a systemic mycosis in Latin America, is regulated by suppressive mechanisms mediated by tolerogenic plasmacytoid-dendritic-cells and regulatory T-cells. Our recent studies revealed that myeloid-derived suppressor cells (MDSCs), are important mediators in PCM. Their suppressive activity on Th1/Th17 immunity was shown to be mediated by inhibitory effect of IL-10, IDO-1 and PD-L1. Studies revealed the chemotherapeutic drug 5-Fluorouracil (5-FU) as a selective MDSC apoptosis-inducing agent, but its in vivo effect on infectious processes remains poorly investigated. METHODS: MDSCs and other leukocytes were evaluated in the lungs of 5-FU-treated mice after four, six, and eight weeks of P. brasiliensis infection. Disease severity and immunological response were evaluated in MDSCs-depleted. RESULTS: 5-FU treatment caused a significant reduction of pulmonary MDSCs and fungal loads. The specific depletion of MDSCs by 5-FU reduced all pulmonary CD4+ T-cell populations (Th1, Th2, Th17, and Treg) resulting in improved tissue pathology and increased survival rates. Importantly, this reduction was concomitant with increased frequencies of Th1/Th17 cells and the increased levels of Th1/Th2/Th17 cytokines in the lungs and liver of treated mice suggesting an early and efficient protective effect of these cells. Furthermore, the immuneprotection conferred by the specific depletion of MDSCs by 5FU treatment could be reversed by the adoptive transfer of MDSCs. CONCLUSIONS: 5-FU treatment depletes lung-MDSCs of P. brasiliensis-infected mice resulting in enhanced immunity. The protective effect of 5-FU treatment in pulmonary PCM suggests that the specific depletion of MDSCs can be viewed as a potential immunotherapeutic tool for PCM.

2.
Oncol Lett ; 28(1): 296, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38737977

RESUMO

Gastric cancer (GC) ranks fifth globally in cancer diagnoses and third for cancer-related deaths. Chemotherapy with 5-fluorouracil (5-FU), a primary treatment, faces challenges due to the development of chemoresistance. Tumor microenvironment factors, including C-C motif chemokine receptor 3 (CCR3), can contribute to chemoresistance. The present study evaluated the effect of CCR3 receptor inhibition using the antagonist SB 328437 and the molecular dynamics of this interaction on resistance to 5-FU in gastric cancer cells. The 5-FU-resistant AGS cell line (AGS R-5FU) demonstrated notable tolerance to higher concentrations of 5-FU, with a 2.6-fold increase compared with the parental AGS cell line. Furthermore, the mRNA expression levels of thymidylate synthase (TS), a molecular marker for 5-FU resistance, were significantly elevated in AGS R-5FU cells. CCR3 was shown to be expressed at significantly higher levels in these resistant cells. Combining SB 328437 with 5-FU resulted in a significant decrease in cell viability, particularly at higher concentrations of 5-FU. Furthermore, when SB 328437 was combined with 5-FU at a high concentration, the relative mRNA expression levels of CCR3 and TS decreased significantly. Computational analysis of CCR3 demonstrated dynamic conformational changes, especially in extracellular loop 2 region, which indicated potential alterations in ligand recognition. Docking simulations demonstrated that SB 328437 bound to the allosteric site of CCR3, inducing a conformational change in ECL2 and hindering ligand recognition. The present study provides comprehensive information on the molecular and structural aspects of 5-FU resistance and CCR3 modulation, highlighting the potential for therapeutic application of SB 328437 in GC treatment.

3.
Nutr Res ; 125: 1-15, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38428258

RESUMO

Açaí seed extract (ASE) is obtained from Euterpe oleracea Mart. (açaí) plant (Amazon region) has high nutritional and functional value. ASE is rich in polyphenolic compounds, mainly proanthocyanidins. Proanthocyanidins can modulate the immune system and oxidative stress by inhibiting the toll-like receptor-4 (TLR-4)/myeloid differentiation primary response 88 (MyD88)/nuclear factor-κB (NF-κB) pathway. A great deal of evidence suggests that inflammatory cytokines and oxidative stress contribute to the pathogenesis of intestinal mucositis, and these events can lead to intestinal dysmotility. We hypothesized that ASE acts as an anti-inflammatory and antioxidant compound in intestinal mucositis induced by 5-fluorouracil (5-FU) through modulation of the TLR-4/MyD88/phosphatidylinositol-3-kinase α/mechanistic target of rapamycin/NF-κBp65 pathway. The animals were divided into linear 5-FU (450 mg/kg) and 5-FU + ASE (10, 30, and 100 mg/kg) groups. The weight loss of the animals was evaluated daily. Samples from duodenum, jejunum, and ileum were obtained for histopathological, biochemical, and functional analyses. ASE reduced weight loss, inflammatory parameters (interleukin-1ß; tumor necrosis factor-α; myeloperoxidase activity) and the gene expression of mediators involved in the TLR-2/MyD88/NF-κB pathway. ASE prevented histopathological changes with beneficial effects on gastrointestinal transit delay, gastric emptying, and intestinal absorption/permeability. In conclusion, ASE protects the integrity of the intestinal epithelial barrier by inhibiting the TLR/MyD88/PI3K/mechanistic target of rapamycin/NF-κBp65 pathway.


Assuntos
Euterpe , Fluoruracila , Mucosite , Fator 88 de Diferenciação Mieloide , Extratos Vegetais , Polifenóis , Sementes , Transdução de Sinais , Serina-Treonina Quinases TOR , Receptor 4 Toll-Like , Animais , Receptor 4 Toll-Like/metabolismo , Mucosite/induzido quimicamente , Mucosite/tratamento farmacológico , Mucosite/prevenção & controle , Mucosite/metabolismo , Fator 88 de Diferenciação Mieloide/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Transdução de Sinais/efeitos dos fármacos , Extratos Vegetais/farmacologia , Sementes/química , Polifenóis/farmacologia , Masculino , Euterpe/química , Camundongos , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/metabolismo , Fator de Transcrição RelA/metabolismo , Antioxidantes/farmacologia , Fosfatidilinositol 3-Quinases/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Anti-Inflamatórios/farmacologia , NF-kappa B/metabolismo
4.
Toxicol Res (Camb) ; 13(2): tfae049, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38533178

RESUMO

Introduction: 5-fluorouracil (5-FU) and methotrexate (MTX) are the antineoplastic drugs most commonly used worldwide. Considered cytotoxic, these pharmaceuticals exhibit low specificity, causing damage not only to cancer cells but also to healthy cells in organisms. After being consumed and metabolized, these drugs are excreted through urine and feces, followed by wastewater treatment. However, conventional treatments do not have the capacity to completely remove these substances, risking their introduction into freshwater systems. This could pose a risk to human health even at low concentrations. Aims: Thus, the present study aimed to investigate the genotoxicity, cytotoxicity, and mutagenicity of 5-FU and MTX at environmentally relevant concentrations after a long-term exposure, using adult male rats as an experimental model. Methods: Male Wistar rats (70 days old) were distributed into 4 groups (n = 10/group): control, received only vehicle; MTX, received methotrexate at 10ngL-1; 5-FU received 5-fluorouracil at 10ngL-1; and MTX + 5-FU, received a combination of MTX and 5-FU at 10ngL-1 each. The period of exposure was from postnatal day (PND) 70 to PND 160, through drinking water. After that, the animals were euthanized and the samples (liver, testis, femoral bone marrow, and peripheral blood) were obtained. Results: Increased DNA fragmentation was observed in the peripheral blood, liver, and testis, altering the parameters of the tail moment and tail intensity in the Comet assay. Besides, the change in the ratio between PCE and NCE indicates bone marrow suppression. Conclusion: These findings warn the adverse effects for the general population worldwide chronically exposed to these drugs at trace concentration unintentionally.

5.
J Cell Biochem ; 125(2): e30517, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38224178

RESUMO

Colorectal cancer (CRC) is the third most common and deadliest cancer globally. Regimens using 5-fluorouracil (5FU) and Oxaliplatin (OXA) are the first-line treatment for CRC, but tumor recurrence is frequent. It is plausible to hypothesize that differential cellular responses are triggered after treatments depending on the genetic background of CRC cells and that the rational modulation of cell tolerance mechanisms like autophagy may reduce the regrowth of CRC cells. This study proposes investigating the cellular mechanisms triggered by CRC cells exposed to 5FU and OXA using a preclinical experimental design mimicking one cycle of the clinical regimen (i.e., 48 h of treatment repeated every 2 weeks). To test this, we treated CRC human cell lines HCT116 and HT29 with the 5FU and OXA, combined or not, for 48 h, followed by analysis for two additional weeks. Compared to single-drug treatments, the co-treatment reduced tumor cell regrowth, clonogenicity and stemness, phenotypes associated with tumor aggressiveness and poor prognosis in clinics. This effect was exerted by the induction of apoptosis and senescence only in the co-treatment. However, a week after treatment, cells that tolerated the treatment had high levels of autophagy features and restored the proliferative phenotype, resembling tumor recurrence. The pharmacologic suppression of early autophagy during its peak of occurrence, but not concomitant with chemotherapeutics, strongly reduced cell regrowth. Overall, our experimental model provides new insights into the cellular mechanisms that underlie the response and tolerance of CRC cells to 5FU and OXA, suggesting optimized, time-specific autophagy inhibition as a new avenue for improving the efficacy of current treatments.


Assuntos
Neoplasias Colorretais , Humanos , Oxaliplatina/farmacologia , Oxaliplatina/uso terapêutico , Neoplasias Colorretais/genética , Recidiva Local de Neoplasia , Células HT29 , Fluoruracila/farmacologia , Fluoruracila/uso terapêutico , Apoptose , Autofagia , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos/genética
6.
Anticancer Agents Med Chem ; 24(7): 477-487, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38265381

RESUMO

Colorectal cancer is the third most common cancer and the second in cases of cancer-related death. Polytherapy generates many adverse effects, leading the patient to give up. Nanotechnology has been studied in recent years to circumvent limitations. Groups composed of polymeric, lipid, and inorganic nanoparticles are the most purpose. Thus, the objective of this work is to bring information on how nanosystems can improve the chemotherapeutic treatment for colorectal cancer. Therefore, a search in journals such as "LILACS", "SciELO" and "PubMed/Medline" was performed, resulting in 25,000 articles found when applied the search engines "nanoparticle," "colorectal cancer," "malignant neoplasms," and "chemotherapy." After inclusion and exclusion factors, 24 articles remained, which were used as the basis for this integrative review. The results reveal that, regardless of the choice of matrix, nanoparticles showed an increase in bioavailability of the active, increasing the half-life by up to 13 times, modified release, as well as a significant reduction in tumor size, with cell viability up to 20% lower than the free drug tested, in different colorectal cancer cell lines, such as HCT-116, HT-29, and CaCo-2. However, more in vivo and clinical studies need to be performed, regardless of the formulation of its matrix, aiming at a higher rate of safety for patients and stability of the formulations, as well as knowledge of detailed indices of its pharmacokinetics and pharmacodynamics, seeking to avoid further damage to the recipient organism.


Assuntos
Antineoplásicos , Neoplasias Colorretais , Nanomedicina , Nanopartículas , Humanos , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/patologia , Antineoplásicos/farmacologia , Antineoplásicos/química , Nanopartículas/química , Ensaios de Seleção de Medicamentos Antitumorais , Proliferação de Células/efeitos dos fármacos , Animais , Sobrevivência Celular/efeitos dos fármacos
7.
Aesthetic Plast Surg ; 48(3): 510-518, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37620566

RESUMO

INTRODUCTION: Seroma is a frequent complication that can affect the final result of reconstructive and cosmetic surgeries. METHODOLOGY: This study evaluated the effectiveness of 5-Fluorouracil and 75% hypertonic glucose in preventing seroma in a mastectomy rat model, as well as cellular and vascular events in adjacent tissues. A left mastectomy with lymphadenectomy was performed in 60 Wistar-Albino female rats. Animals randomly allocated to the control group (Group I; n = 20) were sutured right after mastectomy. The intervention groups received 1.0 mL of 75% hypertonic glucose (Group II; n = 20) or 1.0 mL of 5-Fluorouracil (Group III; n = 20) at the surgical site before suturing. The assessment of the presence of seroma was performed in all animals at 24, 48, and 72 h and on the 7th and 12th postoperative day. After the 12th day, a tissue sample was taken from the surgical site and sent for histological analysis. The occurrence of seroma was assessed using GEE. A significance level of 5% was adopted. RESULTS: Differences in seroma formation over time were observed for both Control Group I (p=0.041) and Intervention Group II (p<0.001). In Intervention Group III, there was no difference in the percentage and volume of seroma across the assessment points (p=0.627). When both the Control and Intervention Group II were compared to Intervention Group III, we found a reduction in seroma formation in the last group. The reduction in the inflammatory process was more regular to Intervention Group III. CONCLUSION: In this animal model, 5-Fluorouracil was more effective in preventing seroma formation than 75% Hypertonic Glucose. No Level Assigned This journal requires that authors assign a level of evidence to each submission to which Evidence-Based Medicine rankings are applicable. This excludes Review Articles, Book Reviews, and manuscripts that concern Basic Science, Animal Studies, Cadaver Studies, and Experimental Studies. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .


Assuntos
Glucose , Mastectomia , Ratos , Animais , Mastectomia/efeitos adversos , Seroma/etiologia , Seroma/prevenção & controle , Seroma/cirurgia , Fluoruracila , Ratos Wistar , Modelos Animais
8.
Eur J Pharm Sci ; 192: 106638, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37967657

RESUMO

In this study, nanostructured lipid carriers (NLC) were developed and employed to obtain in situ thermosensitive formulations for the ductal administration and prolonged retention of drugs as a new strategy for breast cancer local treatment. NLC size was influenced by the type and concentration of the oil phase, surfactants, and drug incorporation, ranging from 221.6 to 467.5 nm. The type of liquid lipid influenced paclitaxel and 5-fluorouracil cytotoxicity, with tributyrin-containing NLC reducing IC50 values by 2.0-7.0-fold compared to tricaprylin NLC in MCF-7, T-47D and MDA-MB-231 cells. In spheroids, the NLCs reduced IC50 compared to either drug solution (3.2-6.2-fold). Although a significant reduction (1.26 points, p < 0.001) on the health index of Galleria mellonella larvae was observed 5 days after NLC administration, survival was not significantly reduced. To produce thermosensitive gels, the NLCs were incorporated in a poloxamer (11 %, w/w) dispersion, which gained viscosity (2-fold) at 37 °C. After 24 h, ∼53 % of paclitaxel and 83 % of 5-fluorouracil were released from the NLC; incorporation in the poloxamer gel further prolonged release. Intraductal administration of NLC-loaded gel increased the permanence of hydrophilic (2.2-3.0-fold) and lipophilic (2.1-2.3-fold) fluorescent markers in the mammary tissue compared to the NLC (as dispersion) and the markers solutions. In conclusion, these results contribute to improving our understanding of nanocarrier design with increased cytotoxicity and prolonged retention for the intraductal route. Tributyrin incorporation increased the cytotoxicity of paclitaxel and 5-fluorouracil in monolayer and spheroids, while NLC incorporation in thermosensitive gels prolonged tissue retention of both hydrophilic and hydrophobic compounds.


Assuntos
Neoplasias da Mama , Nanoestruturas , Humanos , Feminino , Portadores de Fármacos/química , Neoplasias da Mama/tratamento farmacológico , Poloxâmero , Lipídeos/química , Nanoestruturas/química , Géis/química , Paclitaxel , Fluoruracila , Tamanho da Partícula
9.
Probiotics Antimicrob Proteins ; 16(1): 275-292, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36652108

RESUMO

Mucositis is a high-incidence side effect in cancer patients undergoing chemotherapy. Next-generation probiotics are emerging as new therapeutic tools for managing various disorders. Studies have demonstrated the potential of Akkermansia muciniphila to increase the efficiency of anticancer treatment and to mitigate mucositis. Due to the beneficial effect of A. muciniphila on the host, we evaluated the dose-response, the microorganism viability, and the treatment protocol of A. muciniphila BAA-835 in a murine model of chemotherapy-induced mucositis. Female Balb/c mice were divided into groups that received either sterile 0.9% saline or A. muciniphila by gavage. Mucositis was induced using a single intraperitoneal injection of 5-fluorouracil. The animals were euthanized three days after the induction of mucositis, and tissue and blood were collected for analysis. Prevention of weight loss and small intestine shortening and reduction of neutrophil and eosinophil influx were observed when animals were pretreated with viable A. muciniphila at 1010 colony-forming units per mL (CFU/mL). The A. muciniphila improved mucosal damage by preserving tissue architecture and increasing villus height and goblet cell number. It also improved the integrity of the epithelial barrier, decreasing intestinal permeability and bacterial translocation. In addition, the treatment prevented the expansion of Enterobacteriaceae. The immunological parameters were also improved by decreasing the expression of pro-inflammatory cytokines (IL6, IL1ß, and TNF) and increasing IL10. In conclusion, pretreatment with 1010 CFU/mL of viable A. muciniphila effectively controlled inflammation, protected the intestinal mucosa and the epithelial barrier, and prevented Enterobacteriaceae expansion in treated mice.


Assuntos
Antineoplásicos , Mucosite , Humanos , Camundongos , Feminino , Animais , Mucosite/induzido quimicamente , Mucosite/tratamento farmacológico , Mucosite/metabolismo , Citocinas/metabolismo , Mucosa Intestinal/metabolismo , Antineoplásicos/farmacologia , Akkermansia
10.
Int. j. morphol ; 41(6): 1816-1823, dic. 2023. ilus, tab
Artigo em Inglês | LILACS | ID: biblio-1528777

RESUMO

SUMMARY: To evaluate the anti-cancer effects of yeast extract on resistant cells, autophagy and necroptosis were investigated in 5-fluorouracil (5-FU)-resistant colorectal cancer cells. Further underlying characteristics on drug resistance were evaluated, focused on ERK-RSK-ABCG2 linkage. SNU-C5 and 5-FU resistant SNU-C5 (SNU-C5/5-FUR) colorectal cancer cells were adopted for cell viability assay and Western blotting to examine the anti-cancer effects of yeast extract. Yeast extract induced autophagy in SNU-C5 cells with increased Atg7, Atg12-5 complex, Atg16L1, and LC3 activation (LC3-II/LC3-I), but little effects in SNU-C5/5-FUR cells with increased Atg12-5 complex and Atg16L1. Both colorectal cancer cells did not show necroptosis after yeast extract treatment. Based on increased ABCG2 and RSK expression after yeast extract treatment, drug resistance mechanisms were further evaluated. As compared to wild type, SNU-C5/5-FUR cells showed more ABCG2 expression, less RSK expression, and less phosphorylation of ERK. ABCG2 inhibitor, Ko143, treatment induces following changes: 1) more sensitivity at 500 mM 5-FU, 2) augmented proliferation, and 3) less phosphorylation of ERK. These results suggest that protective autophagy in SNU-C5/5-FUR cells with increased ABCG2 expression might be candidate mechanisms for drug resistance. As the ERK responses were different from each stimulus, the feasible mechanisms among ERK-RSK-ABCG2 should be further investigated in 5-FU-resistant CRC cells.


Para evaluar los efectos anticancerígenos del extracto de levadura en células resistentes, se investigaron la autofagia y la necroptosis en células de cáncer colorrectal resistentes al 5-fluorouracilo (5-FU). Además se evaluaron otras características subyacentes de la resistencia a los medicamentos centrándose en el enlace ERK-RSK-ABCG2. Se usaron células de cáncer colorrectal SNU-C5 (SNU-C5/5-FUR) resistentes a SNU-C5 y 5- FU para el ensayo de viabilidad celular y la transferencia Western para examinar los efectos anticancerígenos del extracto de levadura. El extracto de levadura indujo autofagia en células SNU-C5 con mayor activación de Atg7, complejo Atg12-5, Atg16L1 y LC3 (LC3-II/LC3-I), pero pocos efectos en células SNU-C5/5-FUR con aumento de Atg12-5 complejo y Atg16L1. Ambas células de cáncer colorrectal no mostraron necroptosis después del tratamiento con extracto de levadura. Se evaluaron los mecanismos de resistencia a los medicamentos. en base al aumento de la expresión de ABCG2 y RSK después del tratamiento con extracto de levadura.En comparación con las de tipo salvaje, las células SNU-C5/5-FUR mostraron más expresión de ABCG2, menos expresión de RSK y menos fosforilación de ERK. El tratamiento con inhibidor de ABCG2, Ko143, induce los siguientes cambios: 1) más sensibilidad a 5-FU 500 mM, 2) proliferación aumentada y 3) menos fosforilación de ERK. Estos resultados sugieren que la autofagia protectora en células SNU-C5/5-FUR con mayor expresión de ABCG2 podría ser un mecanismo candidato para la resistencia a los medicamentos. Como las respuestas de ERK fueron diferentes de cada estímulo, los mecanismos factibles entre ERK-RSK- ABCG2 deberían investigarse más a fondo en células CCR resistentes a 5-FU.


Assuntos
Autofagia , Extratos Vegetais/farmacologia , Neoplasias Colorretais/tratamento farmacológico , Antineoplásicos/farmacologia , Leveduras , Células Tumorais Cultivadas , Sobrevivência Celular/efeitos dos fármacos , Western Blotting , Resistencia a Medicamentos Antineoplásicos , Proteínas Quinases S6 Ribossômicas 90-kDa , Eletroforese , Fluoruracila , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP , Necroptose
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