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1.
Nature ; 630(8018): 976-983, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38867048

RESUMO

Interleukin (IL-)23 is a major mediator and therapeutic target in chronic inflammatory diseases that also elicits tissue protection in the intestine at homeostasis or following acute infection1-4. However, the mechanisms that shape these beneficial versus pathological outcomes remain poorly understood. To address this gap in knowledge, we performed single-cell RNA sequencing on all IL-23 receptor-expressing cells in the intestine and their acute response to IL-23, revealing a dominance of T cells and group 3 innate lymphoid cells (ILC3s). Unexpectedly, we identified potent upregulation of the immunoregulatory checkpoint molecule cytotoxic T-lymphocyte-associated antigen-4 (CTLA-4) on ILC3s. This pathway was activated by gut microbes and IL-23 in a FOXO1- and STAT3-dependent manner. Mice lacking CTLA-4 on ILC3s exhibited reduced regulatory T cells, elevated inflammatory T cells and more-severe intestinal inflammation. IL-23 induction of CTLA-4+ ILC3s was necessary and sufficient to reduce co-stimulatory molecules and increase PD-L1 bioavailability on intestinal myeloid cells. Finally, human ILC3s upregulated CTLA-4 in response to IL-23 or gut inflammation and correlated with immunoregulation in inflammatory bowel disease. These results reveal ILC3-intrinsic CTLA-4 as an essential checkpoint that restrains the pathological outcomes of IL-23, suggesting that disruption of these lymphocytes, which occurs in inflammatory bowel disease5-7, contributes to chronic inflammation.


Assuntos
Imunidade Inata , Inflamação , Interleucina-23 , Linfócitos , Animais , Feminino , Humanos , Masculino , Camundongos , Antígeno CTLA-4/metabolismo , Proteína Forkhead Box O1/metabolismo , Proteína Forkhead Box O1/genética , Microbioma Gastrointestinal , Inflamação/imunologia , Inflamação/patologia , Inflamação/metabolismo , Interleucina-23/imunologia , Intestinos/imunologia , Intestinos/patologia , Linfócitos/imunologia , Linfócitos/metabolismo , Camundongos Endogâmicos C57BL , Células Mieloides/metabolismo , Análise da Expressão Gênica de Célula Única , Fator de Transcrição STAT3/metabolismo , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/metabolismo
2.
J Photochem Photobiol B ; 209: 111923, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32559647

RESUMO

The current investigation reports bactericidal and cytotoxicity evaluation of bio-enzymatically formulated nano­gold (AuNPs) using physiologically significant enzyme ß galactosidase. The AuNPs were characterized using spectroscopic and microscopic techniques. The anti-pathogenic efficacy of AuNPs as a potential drug was observed against five contagious bacterial strains of Escherichia coli, Staphylococcus aureus, group B Streptococcus, Acinetobacter baumannii and Klebsiella pneumonia. The estimation of minimum bactericidal concentration, minimum inhibitory concentration, scanning electron microscopy and fluorescence microscopy conclude enhanced bactericidal effects of green AuNPs. The cytotoxicity of AuNPs against human cervical (HeLa), breast (MCF-7) and liver (Hep 3B) cancer cells was evaluated. 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay was adopted to analyze antitumor potential of AuNPs. Cell nuclear morphology associated with apoptosis after treatment with NPs was assessed against MCF-7 cells through 4,6-diamidino-2-phenylindole staining. Apoptotic activity of AuNPs was determined against HeLa cells using annexin V/ propidium iodide double staining by flow cytometric analysis. The AuNPs exhibited excellent efficacy against these cell lines and future prospects of usage as potential nano-drugs and drug delivery vehicles.


Assuntos
Antibacterianos/farmacologia , Antineoplásicos/farmacologia , Ouro/química , Nanopartículas Metálicas/química , beta-Galactosidase/metabolismo , Antibacterianos/química , Antineoplásicos/química , Linhagem Celular Tumoral , Humanos , Testes de Sensibilidade Microbiana , Microscopia Eletrônica de Transmissão , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
3.
Eur J Pharm Biopharm ; 152: 270-281, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32470636

RESUMO

Polysaccharide antigens do not promote antibody class switching and memory antibody response, thus require conjugation with a T cell dependent carrier protein to generate protective immune response. The intensity of immune responses varies with the carrier proteins for the same carbohydrate antigen and most of the carrier proteins do not generate strong immune responses. Vi polysaccharide and r-flagellin of Salmonella typhi were conjugated and formulated in PLA particles as nanoglycoconjugate which not only generated strong immune response but also promoted antibody class switching and elicited memory antibody response from single point immunization. Nanoglycoconjugate immunization also modulate anti-inflammatory property of Vi polysaccharide with an enhance secretion of pro-inflammatory cytokine TNF-α and IL-6. This was with concomitant decrease of IFN-γ production, antibody class switching from IgG3 to IgG2 with memory antibody generation against Vi polysaccharide. Antibody elicited by nanoglycoconjugate showed better opsonization and clearance of Salmonella typhi in THP-1 macrophages as compared to Vi-flagellin glycoconjugate and Vi TT (Typhbar®). Delivery of glycoconjugate through nanoparticles provides a platform technology for improving the immunogenicity of polysaccharide based vaccines.


Assuntos
Glicoconjugados/imunologia , Imunidade/imunologia , Nanopartículas/química , Poliésteres/química , Polissacarídeos Bacterianos/imunologia , Salmonella typhi/imunologia , Animais , Anticorpos Antibacterianos/imunologia , Formação de Anticorpos/imunologia , Antígenos/imunologia , Linhagem Celular , Feminino , Imunização/métodos , Imunoglobulina G/imunologia , Interleucina-6/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Células RAW 264.7 , Fator de Necrose Tumoral alfa/imunologia , Vacinas Tíficas-Paratíficas/imunologia , Vacinação/métodos , Vacinas Conjugadas/imunologia
4.
Front Chem ; 7: 787, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31799242

RESUMO

In general, neurodegenerative disorders have a great deal of correlation with the misfolded as well as aggregated forms of protein-based macromolecules. Among various species formed during the aggregation process, protein oligomers have been classified as most toxic entities against several types of living cells. A series of chemicals have been developed to inhibit protein aggregation as a measure to regulate neurodegenerative diseases. Recently, various classes of nanoparticles have also been reported to inhibit protein aggregation. In the present study, we synthesized fluorescent gold nanoparticles (B-AuNPs) employing Olax scandens leaf extract. Next, an in vitro study was performed to assess the effect of as-synthesized B-AuNPs on the aggregation behavior of the ovalbumin (OVA) and other related model proteins. We performed an extensive study to elucidate anti-amyloidogenic properties of nano-sized entities and established that small-sized B-AuNPs manifest chaperone potential against protein aggregation. Further, we exploited as-synthesized B-AuNPs as a mean to prevent protein aggregation mediated toxicity in neuroblastoma cells.

5.
Sci Rep ; 9(1): 12288, 2019 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-31444363

RESUMO

Nano-sized drug delivery systems (NDDS) have been widely exploited to achieve targeted delivery of pharmaco-materials. Traditional pharmaceutical approaches, implied in the synthesis of nano-formulations, are obscure owing to the incompatible physico-chemical properties of the core drug as well as some other factors crucial in development of NDDS. Infact, most of the existing methods used in development of NDDS rely on usage of additives or excipients, a special class of chemicals. Barring few exceptions, the usage of synthetic excipients ought to be curtailed because of several associated undesirable features. Such issues necessitate strategies that lead to development of the synthetic excipient free drug delivery system. Plant based extracts have great potential to induce synthesis of nano-sized particles. Considering this fact, here we propose a prototype employing orange fruit juice (OJ) to facilitate bio-mediated synthesis of nano-sized supra-molecular assemblies of 5-fluorouracil (5-FU), a potent anticancer drug. The as-synthesized 5-FU Nanoparticles (NPs) retained the anti-neoplastic efficacy of the parent compound and induced apoptosis in cancer cells. The novel 5-FU NPs formulation demonstrated enhanced efficacy against DMBA induced experimental fibrosarcoma in the mouse model when compared to the micro-sized crystals of parent 5-FU drug.


Assuntos
Citrus sinensis/química , Sistemas de Liberação de Medicamentos , Fibrossarcoma/tratamento farmacológico , Fluoruracila/síntese química , Fluoruracila/uso terapêutico , Sucos de Frutas e Vegetais , Nanopartículas/química , Neoplasias Cutâneas/tratamento farmacológico , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Apoptose/efeitos dos fármacos , Varredura Diferencial de Calorimetria , Caspase 9/metabolismo , Fragmentação do DNA/efeitos dos fármacos , Modelos Animais de Doenças , Progressão da Doença , Feminino , Fibrossarcoma/patologia , Fluoruracila/farmacologia , Cinética , Masculino , Camundongos Endogâmicos BALB C , Nanopartículas/ultraestrutura , Neoplasias Cutâneas/patologia , Espectroscopia de Infravermelho com Transformada de Fourier , Resultado do Tratamento , Difração de Raios X
6.
RSC Adv ; 9(70): 41135-41150, 2019 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-35540086

RESUMO

A bio-nanocomposite matrix of polypyrrole grafted ZnO/chitosan (Ppy/C/Z) was synthesized via the in situ polymerization of pyrrole with different weight fractions of ZnO. Incorporation of ZnO nanoparticles with polypyrrole enhances the photocatalytic, antibacterial as well as cytotoxic properties of the resultant composite. Characterizations of the synthesized product were performed by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and thermal analysis (TGA and DTA). Surface morphology and particle size were determined by SEM and TEM. The elemental composition of the material was studied by EDX coupled with SEM. Electrochemical surface area was calculated from electrochemical double layer capacitance (EDLC) measurements using cyclic voltammetry. The photocatalytic activity of the composite material was tested by monitoring the degradation of reactive orange-16 (RO-16), Coomassie Brilliant Blue R-250 (CBB-R-250) and Methylene Blue (MB) dyes and the composite was found to be an effective catalyst in the presence of a UV light source. Various scavengers were used to detect the reactive species involved in the photocatalytic process. Furthermore, the stability of the photocatalyst was assessed by recycling experiments. Moreover, the Ppy/C/Z bio-nanocomposite shows potential application with anti-bacterial and anti-cancer activity against Gram-positive and Gram-negative bacterial pathogens and human cancer cell lines (HeLa and MCF-7). The experimental data confirm that the bio-nanocomposite of Ppy/C/Z showed excellent anti-bacterial and anti-cancer activity as compared to a pristine polypyrrole and chitosan formulation (Ppy/C). The apoptosis data with varying concentrations of Ppy/C/Z reveal the remarkable activity against these cancer cell lines.

7.
Carbohydr Polym ; 166: 14-23, 2017 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-28385217

RESUMO

Fatty acid functionalized chitosan conjugates are of great interest in cancer therapeutics because of its internalization through receptor mediated endocytosis into the cancer cells. Keeping the above fact into consideration, herein we synthesized the undec-10-enoic acid functionalized chitosan based undecyl-chitosan (U-CS) nano-bioconjugate with the use of DCC as a coupling agent. The U-CS conjugate synthesized was confirmed and characterized by FTIR, 1H NMR, TGA, XRD, SEM and TEM analysis. Generally, it is well established that conjugates of oleic acid with human Alpha-lactalbumin (HAMLET) induce cytotoxicity in the altered cells, but not in healthy cells. To check our presumptions, anti-bacterial and anti-cancer potential of U-CS was evaluated against bacterial pathogens (Gram +ve and Gram -ve) and human cancer cell lines (HeLa, MDA-MB-231 and Hep3B). The results of our study clearly revealed that conjugate showed enhance anti-bacterial, anti-biofilm as well as anti-cancer efficacy as compared to pure and free form of the chitosan.


Assuntos
Antibacterianos/farmacologia , Antineoplásicos/farmacologia , Biofilmes/efeitos dos fármacos , Quitosana/química , Nanoconjugados , Ácidos Undecilênicos/química , Bactérias , Linhagem Celular Tumoral , Humanos , Lactalbumina , Ácido Oleico
9.
J Contemp Dent Pract ; 13(3): 364-70, 2012 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-22918011

RESUMO

BACKGROUND: Butorphanol tartrate, a mixed synthetic agonistantagonist opioid analgesic has been used for management of postoperative pain in minor and major surgical procedures.(14,20) Tramadol hydrochloride is a centrally acting opioid which is effectively used in postoperative pain in various minor and major surgeries. MATERIALS AND METHODS: Twenty subjects selected randomly received butorphanol tartrate 1 mg intramuscular and 20 subjects received tramadol hydrochloride 50 mg intramuscular after the removal of mandibular third molars. Time of injection, amount of anesthetic injected, duration of surgery, adverse effects were recorded.(21) RESULTS: The mean amount of LA administered in butorphanol group was 2.6450 ml and in tramadol group was 2.640 ml respectively, the mean duration for surgery was 56.75 and 53.5 minutes for butorphanol and tramadol groups respectively which was statistically not significant. Pain assessment was done with VAS which showed mean of 19.2 and 15.5 mm (p = 0.001) which was significant for butorphanol and tramadol respectively after 12 hours. The mean time for rescue medication requirement was 5.9 hours (for tramadol) and 8.4 hours (for butorphanol). Effective analgesic activity was seen by butorphanol 1 mg intramuscular then tramadol 50 mg. CONCLUSION: Butorphanol 1 mg was more effective than tramadol 50 mg in respect to postoperative analgesia.


Assuntos
Analgésicos Opioides/administração & dosagem , Butorfanol/administração & dosagem , Dente Serotino/cirurgia , Dor Pós-Operatória/prevenção & controle , Extração Dentária , Tramadol/administração & dosagem , Distribuição de Qui-Quadrado , Feminino , Humanos , Injeções Intramusculares , Masculino , Mandíbula/cirurgia , Duração da Cirurgia , Medição da Dor , Distribuição por Sexo , Estatísticas não Paramétricas , Dente Impactado/cirurgia , Adulto Jovem
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