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1.
Food Chem ; 458: 140213, 2024 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-38943951

RESUMO

This work investigated the feasibility of applying headspace solid phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC/MS) combining olfactory visualization for flavor characterization of black garlic. Volatile organic compounds (VOCs) analysis was performed to select important differential VOCs during black garlic processing. A multi-channels nanocomposite CSA assembled with two porous metal-organic frameworks was then developed to characterize flavor profiles changes during black garlic processing, and garlic samples during processing could be divided into five clusters, consistent with VOCs analysis. Artificial neural network (ANN) model outperformed other pattern recognition methods in discriminating processing stages. Furthermore, SVR model for odor sensory scores with the correlation coefficient for prediction set of 0.8919 exhibited a better performance than PLS model, indicating a preferable prediction ability for odor quality. This work demonstrated that the nanocomposite CSA combining appropriate chemometrics can offer an effective tool for objectively and rapidly characterizing flavor quality of black garlic or other food matrixes.


Assuntos
Aromatizantes , Alho , Cromatografia Gasosa-Espectrometria de Massas , Odorantes , Microextração em Fase Sólida , Compostos Orgânicos Voláteis , Alho/química , Compostos Orgânicos Voláteis/química , Microextração em Fase Sólida/métodos , Aromatizantes/química , Odorantes/análise , Colorimetria , Nanoestruturas/química , Paladar , Quimiometria
2.
Chemistry ; 29(62): e202301624, 2023 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-37587551

RESUMO

Histone lysine crotonylation (Kcr) is one newly discovered acylation modification and regulates numerous pathophysiological processes. The binding affinity between Kcr and its interacting proteins is generally weak, which makes it difficult to effectively identify Kcr-interacting partners. Changing the amide of crotonyl to an ester increased reactivity with proximal cysteines and retained specificity for Kcr antibody. The probe "H3g27Cr" was designed by incorporating the ester functionality into a H3K27 peptide. Using this probe, multiple Kcr-interacting partners including STAT3 were successfully identified, and this has not been reported previously. Further experiments suggested that STAT3 possibly could form complexes with Histone deacetylase HDACs to downregulate the acetylation and crotonylation of Histone H3K27. Our unique design provided intriguing tools to further explore Kcr-interacting proteins and elucidate their working mechanisms.


Assuntos
Histonas , Lisina , Histonas/metabolismo , Lisina/química , Peptídeos/metabolismo , Processamento de Proteína Pós-Traducional , Ésteres
3.
Biochem Biophys Rep ; 35: 101508, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37448811

RESUMO

Peptides can be used as effective molecular tool for covalent modification of proteins and play important roles in ligand directed covalent modification. Tyr-selective protein modifications exert a profound impact on protein functionality. Here, we developed a general strategy that involves nucleophilic addition of alkyne for tyrosine modification. The terminal alkyne of propargyl sulfonium is motivated by the sulfonium center to react with phenolic hydroxyl. This approach provides a straightforward method for tyrosine modification due to its high yield in aqueous solution at physiological temperature. In addition, cyclic peptides could be obtained via adjusting pH to 8.0 from peptides consisting of tyrosine and methionine modified by propargyl bromide, and the resulting cyclic peptides are proved to have better stability, excellent 2-mercaptopyridine resistance and improved cellular uptakes. Furthermore, molecules made from the propargylated sulfonium have the potential to be used as warheads against tyrosine containing biomolecules. Collectively, we develop a direct and uncomplicated technique for modifying tyrosine residues, the strategy concerned can be widely utilized to construct stable peptides and biomolecules imaging.

4.
J Am Chem Soc ; 145(14): 7879-7887, 2023 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-37001133

RESUMO

The development of bifunction al molecules, which can enable targeted RNA degradation, targeted protein acetylation, or targeted protein degradation, remains a time-consuming process that requires tedious optimization. We propose a split-and-mix nanoplatform that serves as a self-adjustable platform capable of facile screening, programmable ligand ratios, self-optimized biomolecule spatial recognition, and multifunctional applications. Herein, we demonstrate the potential of our proposed nanoplatform by showcasing proteolysis-targeting chimeras (PROTACs), namely, split-and-mix PROTAC (SM-PROTAC). We highlight the scope of our platform through the targeted disruption of intracellular therapeutic targets involving ERα, CDK4/6, AR, MEK1/2, BRD2/4, BCR-ABL, etc. These studies confirm the effectiveness and universality of the SM-PROTAC platform for proximity-induced applications. This platform is programmable, with significant potential applications to biomolecule regulation, including the fields of epigenetics, gene editing, and biomolecule modification regulation.


Assuntos
Processamento de Proteína Pós-Traducional , Proteólise
5.
Chem Sci ; 14(3): 604-612, 2023 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-36741507

RESUMO

Visible-light-mediated methods were heavily studied as a useful tool for cysteine-selective bio-conjugation; however, many current methods suffer from bio-incompatible reaction conditions and slow kinetics. To address these challenges, herein, we report a transition metal-free thiol-sulfoxonium ylide photo-click reaction that enables bioconjugation under bio-compatible conditions. The reaction is highly cysteine-selective and generally finished within minutes with naturally occurring riboflavin derivatives as organic photocatalysts. The catalysts and substrates are readily accessible and bench stable and have satisfactory water solubility. As a proof-of-concept study, the reaction was smoothly applied in chemo-proteomic analysis, which provides efficient tools to explore the druggable content of the human proteome.

6.
ACS Nano ; 16(11): 19509-19522, 2022 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-36318615

RESUMO

Peptide-based neoantigen vaccines hold tremendous potential for personalized tumor immunotherapy. However, effective delivery and controllable release of antigen peptides remain major challenges in stimulating robust and sustained immune responses. Programmable DNA nanodevices provide accurate fixed positions for antigens, which are convenient for the calculation of clinical dosage, and hold great potential as precise carriers. Here, a peptide-nucleic acid conjugate was prepared, which was driven by a propargyl sulfonium-based efficient and reversible bio-orthogonal reaction under weakly alkaline conditions, and folded into regular DNA nanodevice vaccines. The well-defined nanoplatform not only exhibits outstanding stability in serum, satisfactory safety, and effective internalization by antigen-presenting cells (RAW264.7 and BMDCs) but also obviously enhances cytokine (TNF-α, IL-6, and IL-12) secretion for further immune response. In vivo, the nanovaccine cooperating with OVA model antigens and CpG adjuvants stimulated an antigen-specific CD8+T cell response, significantly preventing the lung metastases of melanoma. In the B16-OVA tumor-bearing model, the growth inhibition rate of melanoma reached up to 50%. Similarly, the DNA nanodevice with neoantigen induced up to a maximum degree of complete MC-38 tumor regression in 80% of mice, possibly owing to antigen peptide reversible release driven by sulfonium and further cross-presentation. In brief, this study demonstrates that DNA nanodevices with sulfonium centers can provide a precise, biocompatible, and effective co-delivery vaccine platform for tumor immunotherapy and prevention.


Assuntos
Vacinas Anticâncer , Melanoma , Vacinas , Camundongos , Animais , Apresentação de Antígeno , Imunoterapia , Antígenos , Melanoma/tratamento farmacológico , Peptídeos/farmacologia , DNA , Camundongos Endogâmicos C57BL , Células Dendríticas
7.
Org Lett ; 24(39): 7205-7209, 2022 10 07.
Artigo em Inglês | MEDLINE | ID: mdl-36169233

RESUMO

The ligand-directed (LD) chemistry provides powerful tools for site-specific modification of proteins. We utilized a peptide with an appended methionine (Met) as a ligand; then, the Met thioether was modified into sulfonium which enabled a proximity induced group transfer onto protein cysteine in the vicinity upon peptide-target binding. The sulfonium warhead could be easily constructed with unprotected peptides, and the transferable group scope was conducted on model protein PDZ and its ligand peptides. In addition, a living cell labeling was successfully achieved.


Assuntos
Cisteína , Peptídeos , Ligantes , Metionina , Peptídeos/metabolismo , Proteínas , Sulfetos
8.
Chem Sci ; 13(28): 8289-8296, 2022 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-35919717

RESUMO

Histidine (His, H) undergoes various post-translational modifications (PTMs) and plays multiple roles in protein interactions and enzyme catalyzed reactions. However, compared with other amino acids such as Lys or Cys, His modification is much less explored. Herein we describe a novel visible-light-driven thioacetal activation reaction which enables facile modification on histidine residues. An efficient addition to histidine imidazole N3 under biocompatible conditions was achieved with an electrophilic thionium intermediate. This method allows chemo-selective modification on peptides and proteins with good conversions and efficient histidine-proteome profiling with cell lysates. 78 histidine containing proteins were for the first time found with significant enrichment, most functioning in metal accumulation in brain related diseases. This facile His modification method greatly expands the chemo-selective toolbox for histidine-targeted protein conjugation and helps to reveal histidine's role in protein functions.

9.
Methods Mol Biol ; 2530: 169-175, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35761049

RESUMO

Stapled peptides have received widespread attention in therapeutics due to the superior membrane penetration and in vivo stability. We have developed a series of methods including CIH, TD coupling, Met-Met, and Cys-Met bis-alkylation strategy to switch peptides' secondary structure and enhance their stability and cellular uptake. Here we focus on the peptide macrocyclization method of Met-Met and Cys-Met bis-alkylation strategy to generate more stable and permeable sulfonium-tethered peptides to avoid tedious synthesis, which can be utilized for drug delivery and further broad biological applications.


Assuntos
Peptídeos , Alquilação , Peptídeos/química , Estrutura Secundária de Proteína
10.
Org Lett ; 24(7): 1448-1453, 2022 02 25.
Artigo em Inglês | MEDLINE | ID: mdl-35156827

RESUMO

Herein, we report the first facile Cu-free click reaction between alkynyl sulfonium and azide at ambient temperatures in aqueous media. DFT computations indicate that the sulfonium group is the key factor to gaining reactivity by stabilizing LUMO+1 and influencing the charge distribution of the triple bond. Sulfonium alkynes can be easily synthesized and scaled up, and most of them are biocompatible. We prepared candidate molecules and tested their use in multiple proof-of-concept biological applications.

11.
Braz J Med Biol Res ; 53(9): e9000, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32696820

RESUMO

This study aimed to investigate the effect of a caregiver intensive education program (CIEP) on anxiety, depression, and quality of life (QOL) in patients with drug-resistant temporal lobe epilepsy and mesial temporal sclerosis (TLE-MTS) who underwent cortico-amygdalohippocampectomy (CAH). Ninety patients with drug-resistant TLE-MTS who underwent CAH and their caregivers were recruited and randomly allocated to the CIEP group or control group as 1:1 ratio. Caregivers received the CIEP program or routine guidance/education (control group). Anxiety/depression and QOL in patients at month (M)0, M1, M3, and M6 were assessed by the Hospital Anxiety and Depression Scale (HADS) scale and the QOL in Epilepsy Inventory-31 (QOLIE-31), respectively. Treatment efficacy at M6 was assessed by Engel classification. The HADS-anxiety score at M3 (P=0.049) and M6 (P=0.028), HADS-anxiety score change (M6-M0) (P=0.001), percentage of anxiety patients at M6 (P=0.025), and anxiety severity at M6 (P=0.011) were all decreased in the CIEP group compared with the control group. The HADS-depression score at M6 (P=0.033) and HADS-depression score change (M6-M0) (P=0.022) were reduced, while percentage of depression patients at M6 (P=0.099) and depression severity at M6 (P=0.553) showed no difference in the CIEP group compared with the control group. The QOLIE-31 score at M6 (P=0.043) and QOLIE-31 score change (M6-M0) (P=0.010) were both elevated in the CIEP group compared with the control group. In conclusion, CIEP for caregivers contributed to the recovery of anxiety and depression as well as the improvement of QOL in patients with drug-resistant TLE-MTS who underwent CAH.


Assuntos
Cuidadores/educação , Epilepsia do Lobo Temporal , Qualidade de Vida , Ansiedade , Depressão , Humanos , Esclerose
12.
Chem Commun (Camb) ; 56(26): 3741-3744, 2020 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-32124910

RESUMO

Continuous efforts have been invested in the selective modification of proteins. Herein, we first report the construction of sulfonium tethered cyclic peptides via an intramolecular cyclization by an aliphatic halide. This cyclization could enhance the stability and cellular uptake of peptides. Furthermore, the sulfonium center could be recognized by cysteine in the vicinity of the protein-peptide interacting interface and form a peptide-protein conjugate.


Assuntos
Metionina/química , Peptídeos Cíclicos/química , Compostos de Sulfônio/química , Alquilação , Transporte Biológico , Ciclização , Células HeLa , Humanos , Peptídeos Cíclicos/farmacologia
13.
Braz. j. med. biol. res ; 53(9): e9000, 2020. tab, graf
Artigo em Inglês | LILACS, Coleciona SUS | ID: biblio-1132554

RESUMO

This study aimed to investigate the effect of a caregiver intensive education program (CIEP) on anxiety, depression, and quality of life (QOL) in patients with drug-resistant temporal lobe epilepsy and mesial temporal sclerosis (TLE-MTS) who underwent cortico-amygdalohippocampectomy (CAH). Ninety patients with drug-resistant TLE-MTS who underwent CAH and their caregivers were recruited and randomly allocated to the CIEP group or control group as 1:1 ratio. Caregivers received the CIEP program or routine guidance/education (control group). Anxiety/depression and QOL in patients at month (M)0, M1, M3, and M6 were assessed by the Hospital Anxiety and Depression Scale (HADS) scale and the QOL in Epilepsy Inventory-31 (QOLIE-31), respectively. Treatment efficacy at M6 was assessed by Engel classification. The HADS-anxiety score at M3 (P=0.049) and M6 (P=0.028), HADS-anxiety score change (M6-M0) (P=0.001), percentage of anxiety patients at M6 (P=0.025), and anxiety severity at M6 (P=0.011) were all decreased in the CIEP group compared with the control group. The HADS-depression score at M6 (P=0.033) and HADS-depression score change (M6-M0) (P=0.022) were reduced, while percentage of depression patients at M6 (P=0.099) and depression severity at M6 (P=0.553) showed no difference in the CIEP group compared with the control group. The QOLIE-31 score at M6 (P=0.043) and QOLIE-31 score change (M6-M0) (P=0.010) were both elevated in the CIEP group compared with the control group. In conclusion, CIEP for caregivers contributed to the recovery of anxiety and depression as well as the improvement of QOL in patients with drug-resistant TLE-MTS who underwent CAH.


Assuntos
Humanos , Qualidade de Vida , Cuidadores/educação , Epilepsia do Lobo Temporal , Ansiedade , Esclerose , Depressão
14.
Mol Med Rep ; 19(1): 327-337, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30431087

RESUMO

Early brain injury (EBI)­induced neuronal apoptosis is primarily responsible for the subsequent complications of aneurysmal subarachnoid hemorrhage (aSAH), which may increase the risk of mortality in patients with aSAH. c­Jun N­terminal kinase (JNK) has been demonstrated to be a promoter of EBI­induced cell apoptosis, although the mechanism has yet to be fully elucidated. The present study aimed to explore whether the role of JNK1 is associated with tumor protein p53 (p53), which is one of the most important factor that triggers cell apoptosis. JNK1 expression was downregulated via in vivo small interfering RNA transfection in an aSAH rat model in order to assess differences in the behavior, survival times, morphology and genetics of the experimental animals. The results revealed that JNK1 inhibition improved the neurological scores and survival times of SAH rats by interrupting cascaded neuronal apoptosis. The interruption of EBI­induced neuronal apoptosis may originate from a decrease in the level of p53 phosphorylation and deactivation of the downstream mitochondrial apoptotic pathway. Taken together, these results suggest that JNK1 may be a promising target for improving the prognosis of patients with aSAH.


Assuntos
Apoptose , Lesões Encefálicas/patologia , Mitocôndrias/patologia , Proteína Quinase 8 Ativada por Mitógeno/metabolismo , Neurônios/patologia , Hemorragia Subaracnóidea/patologia , Proteína Supressora de Tumor p53/metabolismo , Animais , Proteínas Reguladoras de Apoptose/genética , Proteínas Reguladoras de Apoptose/metabolismo , Lesões Encefálicas/metabolismo , Células Cultivadas , Masculino , Mitocôndrias/metabolismo , Proteína Quinase 8 Ativada por Mitógeno/antagonistas & inibidores , Proteína Quinase 8 Ativada por Mitógeno/genética , Neurônios/metabolismo , Fosforilação , RNA Interferente Pequeno , Ratos , Ratos Sprague-Dawley , Hemorragia Subaracnóidea/metabolismo , Proteína Supressora de Tumor p53/genética
15.
Biochem Biophys Res Commun ; 497(1): 430-436, 2018 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-29448108

RESUMO

Microglia/Macrophages have a double-edged role in secondary brain damage after traumatic brain injury (TBI) depending on polarization toward proinflammatory M1 or anti-inflammatory M2 phenotypes. Recently, high-mobility group box 1 (HMGB1) was found to influence the polarization of macrophages. In this study, glycyrrhizin (GL), an inhibitor of HMGB1, was used to investigate whether the inhibition of HMGB1 could modulate microglia/macrophage polarization after TBI. The results showed that treatment with GL improved the neurological function recovery, reduced the lesion volume, and inhibited the release and expression of HMGB1 after TBI. In addition, the administration of GL suppressed M1 phenotype activation and promoted M2 phenotype activation of microglia/macrophages. In conclusion, the results suggested that GL attenuated TBI by inhibiting M1 phenotype while inducing M2 phenotype activation of microglia/macrophages, at least partly through inhibiting HMGB1. Also, targeting HMGB1 to modulate the microglia/macrophage polarization should be one potential therapeutic approach for TBI.


Assuntos
Lesões Encefálicas Traumáticas/tratamento farmacológico , Lesões Encefálicas Traumáticas/imunologia , Ácido Glicirrízico/administração & dosagem , Proteína HMGB1/antagonistas & inibidores , Macrófagos/imunologia , Microglia/imunologia , Neuroproteção/imunologia , Animais , Lesões Encefálicas Traumáticas/patologia , Proteína HMGB1/imunologia , Macrófagos/efeitos dos fármacos , Macrófagos/patologia , Masculino , Microglia/efeitos dos fármacos , Microglia/patologia , Ratos , Ratos Sprague-Dawley , Resultado do Tratamento
16.
Front Pharmacol ; 8: 44, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28239352

RESUMO

This study was aimed to evaluate the effects of celastrol, a natural compound with multiple bioactivities, on multiple sclerosis and optic neuritis (ON) in rat experimental autoimmune encephalomyelitis (EAE). EAE was induced in Sprague Dawley rats using myelin basic protein, and the animals received daily intraperitoneal injections of celastrol or vehicle for 13 days. The EAE rats showed abnormal neurobehavior and inflammatory infiltration and demyelination in the spinal cord. Significantly upregulated mRNA expression of pro-inflammatory cytokines interferon-γ and interleukin-17 and downregulated anti-inflammatory cytokines interleukin-4 were found in the spinal cord of EAE rats. In the study of ON, severely inflammatory responses like in the spinal cord were also seen in the optic nerve, as well as obvious microgliosis. Furthermore, activation of nuclear factor kappa-B and upregulated inducible nitric oxide synthase was observed in the optic nerve. In addition, apoptosis of retinal ganglion cells and dysregulation of apoptotic-associated proteins in the optic nerve were found in EAE rats. Treatment of celastrol potently restored these changes. In most of the indexes, the effects of high dose of celastrol were better than the low dose. Our data conclude that administration of celastrol attenuates multiple sclerosis and ON in EAE via anti-inflammatory and anti-apoptotic effects. These findings provide new pre-clinical evidence for the use of celastrol in treatment of multiple sclerosis.

17.
Int J Oncol ; 49(6): 2387-2398, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27748800

RESUMO

TGF-ß-induced epithelial-mesenchymal transition (EMT) plays an important role in tumor progression. We assessed whether the TGF-ß-induced EMT contributed to vasculogenic mimicry (VM) formation in glioma, we established an SHG44 cell line stably transfected with TGF-ß cDNA loaded lentivirus. SB203580 was employed to inhibit the TGF-ß-induced EMT. The results showed that the VM forming ability of cells could be improved by TGF-ß over-expression. The migration and invasion capabilities of cells were also enhanced due to EMT. SB203580 was able to weaken cell migration, invasion and VM forming abilities via blocking p38/MAPK signaling pathways, but it had tiny influence on MMP/LAMC2 chain. Consequently, we concluded that EMT inhibition via p38/MAPK signaling pathways would partly impair TGF-ß-induced VM formation in glioma.


Assuntos
Transição Epitelial-Mesenquimal/efeitos dos fármacos , Glioma/patologia , Sistema de Sinalização das MAP Quinases/genética , Fator de Crescimento Transformador beta/antagonistas & inibidores , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidores , Inibidores da Angiogênese/farmacologia , Animais , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Plasticidade Celular/fisiologia , Proliferação de Células/efeitos dos fármacos , Glioma/genética , Humanos , Imidazóis/farmacologia , Lentivirus/genética , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Invasividade Neoplásica/patologia , Transplante de Neoplasias , Piridinas/farmacologia , Transfecção , Fator de Crescimento Transformador beta/genética , Transplante Heterólogo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
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