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1.
Brain Res Bull ; 212: 110969, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38705540

RESUMO

Alzheimer's disease (AD) stands as the most prevalent neurodegenerative condition worldwide, and its correlation with microglial function is notably significant. Dl-3-n-butylphthalide (NBP), derived from the seeds of Apium graveolens L. (Chinese celery), has demonstrated the capacity to diminish Aß levels in the brain tissue of Alzheimer's transgenic mice. Despite this, its connection to neuroinflammation and microglial phagocytosis, along with the specific molecular mechanism involved, remains undefined. In this study, NBP treatment exhibited a substantial improvement in learning deficits observed in AD transgenic mice (APP/PS1 transgenic mice). Furthermore, NBP treatment significantly mitigated the total cerebral Aß plaque deposition. This effect was attributed to the heightened presence of activated microglia surrounding Aß plaques and an increase in microglial phagocytosis of Aß plaques. Transcriptome sequencing analysis unveiled the potential involvement of the AGE (advanced glycation end products) -RAGE (receptor for AGE) signaling pathway in NBP's impact on APP/PS1 mice. Subsequent investigation disclosed a reduction in the secretion of AGEs, RAGE, and proinflammatory factors within the hippocampus and cortex of NBP-treated APP/PS1 mice. In summary, NBP alleviates cognitive impairment by augmenting the number of activated microglia around Aß plaques and ameliorating AGE-RAGE-mediated neuroinflammation. These findings underscore the related mechanism of the crucial neuroprotective roles of microglial phagocytosis and anti-inflammation in NBP treatment for AD, offering a potential therapeutic target for the disease.


Assuntos
Doença de Alzheimer , Benzofuranos , Camundongos Transgênicos , Microglia , Fagocitose , Receptor para Produtos Finais de Glicação Avançada , Animais , Microglia/efeitos dos fármacos , Microglia/metabolismo , Benzofuranos/farmacologia , Camundongos , Fagocitose/efeitos dos fármacos , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Receptor para Produtos Finais de Glicação Avançada/metabolismo , Transdução de Sinais/efeitos dos fármacos , Masculino , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Peptídeos beta-Amiloides/metabolismo , Inflamação/metabolismo , Inflamação/tratamento farmacológico , Modelos Animais de Doenças , Presenilina-1/genética , Presenilina-1/metabolismo , Placa Amiloide/metabolismo , Placa Amiloide/patologia , Placa Amiloide/tratamento farmacológico , Doenças Neuroinflamatórias/tratamento farmacológico , Doenças Neuroinflamatórias/metabolismo
2.
J Mater Chem B ; 12(14): 3404-3416, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38487992

RESUMO

Nanoagents for chemodynamic therapy (CDT) hold a promising future in the field of antimicrobials, especially copper peroxide (CuO2) (CP) nanomaterials which have garnered significant attention due to their ability to self-supply H2O2. Nevertheless, the poor stability of CuO2 remains a critical challenge which restricts its practical application in the antibacterial field. In this study, an advanced nano-antimicrobial system HA-CP@Fe3O4 with enzyme-responsive properties is developed by coating hyaluronic acid (HA) on CuO2-loaded iron tetraoxide nanoparticles. The coating of HA not only stabilizes the CuO2 nanomaterials but also provides responsiveness towards the enzyme hyaluronidase, which is typically secreted by some bacteria. The outer layer of HA in HA-CP@Fe3O4 undergoes decomposition in the presence of hyaluronidase-secreting bacteria, resulting in the release of CuO2@Fe3O4. The released CuO2@Fe3O4 then self-supplies H2O2 and generates reactive oxygen species (ROS) within the infected microenvironment through Fenton and Russell effects, to ultimately achieve effective and precise antimicrobial activity. Simultaneously, the magnetic property provided by Fe3O4 allows the substance to be directed towards the infection site. Both in vitro and in vivo tests demonstrated that HA-CP@Fe3O4 exhibited excellent antimicrobial capabilities at low concentration (30 µg mL-1), exceptional biocompatibility and the ability to accelerate wound healing. The findings of this work offer a new and promising approach for targeted and precise CDT.


Assuntos
Peróxido de Hidrogênio , Nanopartículas , Hialuronoglucosaminidase , Antibacterianos/farmacologia , Cicatrização
3.
Angiogenesis ; 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38483712

RESUMO

Pathological retinal angiogenesis profoundly impacts visual function in vascular eye diseases, such as retinopathy of prematurity (ROP) in preterm infants and age-related macular degeneration in the elderly. While the involvement of photoreceptors in these diseases is recognized, the underlying mechanisms remain unclear. This study delved into the pivotal role of photoreceptors in regulating abnormal retinal blood vessel growth using an oxygen-induced retinopathy (OIR) mouse model through the c-Fos/A disintegrin and metalloprotease 17 (Adam17) axis. Our findings revealed a significant induction of c-Fos expression in rod photoreceptors, and c-Fos depletion in these cells inhibited pathological neovascularization and reduced blood vessel leakage in the OIR mouse model. Mechanistically, c-Fos directly regulated the transcription of Adam17 a shedding protease responsible for the production of bioactive molecules involved in inflammation, angiogenesis, and cell adhesion and migration. Furthermore, we demonstrated the therapeutic potential by using an adeno-associated virus carrying a rod photoreceptor-specific short hairpin RNA against c-fos which effectively mitigated abnormal retinal blood vessel overgrowth, restored retinal thickness, and improved electroretinographic (ERG) responses. In conclusion, this study highlights the significance of photoreceptor c-Fos in ROP pathology, offering a novel perspective for the treatment of this disease.

4.
Molecules ; 28(19)2023 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-37836780

RESUMO

Glutarimide-containing polyketides exhibiting potent antitumor and antimicrobial activities were encoded via conserved module blocks in various strains that favor the genomic mining of these family compounds. The bioinformatic analysis of the genome of Burkholderia gladioli ATCC 10248 showed a silent trans-AT PKS biosynthetic gene cluster (BGC) on chromosome 2 (Chr2C8), which was predicted to produce new glutarimide-containing derivatives. Then, the silent polyketide synthase gene cluster was successfully activated via in situ promoter insertion and heterologous expression. As a result, seven glutarimide-containing analogs, including five new ones, gladiofungins D-H (3-7), and two known gladiofungin A/gladiostatin (1) and 2 (named gladiofungin C), were isolated from the fermentation of the activated mutant. Their structures were elucidated through the analysis of HR-ESI-MS and NMR spectroscopy. The structural diversities of gladiofungins may be due to the degradation of the butenolide group in gladiofungin A (1) during the fermentation and extraction process. Bioactivity screening showed that 2 and 4 had moderate anti-inflammatory activities. Thus, genome mining combined with promoter engineering and heterologous expression were proved to be effective strategies for the pathway-specific activation of the silent BGCs for the directional discovery of new natural products.


Assuntos
Burkholderia gladioli , Piperidonas , Policetídeos , Burkholderia gladioli/genética , Burkholderia gladioli/metabolismo , Policetídeos/química , Piperidonas/química , Genômica , Família Multigênica
5.
Gerontology ; 69(12): 1414-1423, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37857262

RESUMO

INTRODUCTION: Telomere length (TL) is generally regarded as a biomarker of aging. TL, which is influenced by sociodemographic factors, has been shown to be inversely associated with morbidity. However, most studies examined the youngest, and whether the findings can be extended to older individuals is less clear. Further, few studies have examined these questions in Chinese older adults. This cross-sectional study examined TL and its associated factors in Chinese aged 75+ years in Hong Kong. METHODS: Participants were from the Mr. and Ms. Osteoporosis cohort. A structured interview on sociodemographic factors and physical measurement was conducted. Frailty and sarcopenia status were respectively determined by Fried's criteria and the Asian Working Group for Sarcopenia definition. TL was measured by a molecular inversion probe-quantitative PCR assay and expressed as a novel telomere/a single copy reference gene (T/S) ratio. Adjusted binary logistic regressions were used to examine the associations between TL and the presence of multimorbidity, age-related diseases, frailty, and sarcopenia. RESULTS: Among 555 participants (mean age 83.6 ± 3.8 years, 41.3% females), the mean T/S ratio was 1.01 ± 0.20. Males had a lower T/S ratio (0.97 ± 0.20) compared with females (1.07 ± 0.18) (p < 0.001). A lower education level was related to a longer TL (p = 0.016). Being a current smoker was related to a shorter TL (p = 0.007). TL was not significantly different across categories of age, subjective socioeconomic status, drinking status, physical activity level, and body mass index (p > 0.05). There were no associations between TL and the presence of multimorbidity, diabetes, stroke, cardiovascular diseases, cognitive impairment, frailty, and sarcopenia. CONCLUSION: Among Chinese aged 75+ years, males had shorter TL compared with females. TL was not associated with age-related diseases, frailty, and sarcopenia in this age group. TL may not be a biological marker of aging among older individuals.


Assuntos
Fragilidade , Sarcopenia , Masculino , Feminino , Humanos , Idoso , Idoso de 80 Anos ou mais , Sarcopenia/epidemiologia , Sarcopenia/genética , Fragilidade/epidemiologia , Fragilidade/genética , Estudos Transversais , População do Leste Asiático , Biomarcadores , Telômero/genética , Encurtamento do Telômero
6.
Nat Commun ; 14(1): 6619, 2023 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-37857663

RESUMO

The broad bioactivities of nonribosomal peptides rely on increasing structural diversity. Genome mining of the Burkholderiales strain Schlegelella brevitalea DSM 7029 leads to the identification of a class of dodecapeptides, glidonins, that feature diverse N-terminal modifications and a uniform putrescine moiety at the C-terminus. The N-terminal diversity originates from the wide substrate selectivity of the initiation module. The C-terminal putrescine moiety is introduced by the unusual termination module 13, the condensation domain directly catalyzes the assembly of putrescine into the peptidyl backbone, and other domains are essential for stabilizing the protein structure. Swapping of this module to another two nonribosomal peptide synthetases leads to the addition of a putrescine to the C-terminus of related nonribosomal peptides, improving their hydrophilicity and bioactivity. This study elucidates the mechanism for putrescine addition and provides further insights to generate diverse and improved nonribosomal peptides by introducing a C-terminal putrescine.


Assuntos
Peptídeos , Putrescina , Peptídeos/genética , Peptídeos/química , Peptídeo Sintases/metabolismo
7.
ACS Synth Biol ; 12(10): 3072-3081, 2023 10 20.
Artigo em Inglês | MEDLINE | ID: mdl-37708405

RESUMO

Bacterial natural products (NPs) are an indispensable source of drugs and biopesticides. Heterologous expression is an essential method for discovering bacterial NPs and the efficient biosynthesis of valuable NPs, but the chassis for Gram-negative bacterial NPs remains inadequate. In this study, we built a Burkholderiales mutant Burkholderia gladioli Δgbn::attB by introducing an integrated site (attB) to inactivate the native gladiolin (gbn) biosynthetic gene cluster, which stabilizes large foreign gene clusters and reduces the native metabolite profile. The growth and successful heterologous production of high-value NPs such as phylogenetically close Burkholderiales-derived antitumor polyketides (PKs) rhizoxins, phylogenetically distant Gammaproteobacteria-derived anti-MRSA (methicillin-resistant Staphylococcus aureus) antibiotics WAP-8294As, and Deltaproteobacteria-derived antitumor PKs disorazols demonstrate that this strain is a potential chassis for Gram-negative bacterial NPs. We further improved the yields of WAP-8294As through promoter insertions and precursor pathway overexpression based on heterologous expression in this strain. This study provides a robust bacterial chassis for genome mining, efficient production, and molecular engineering of bacterial NPs.


Assuntos
Produtos Biológicos , Burkholderia gladioli , Staphylococcus aureus Resistente à Meticilina , Policetídeos , Burkholderia gladioli/genética , Burkholderia gladioli/metabolismo , Staphylococcus aureus Resistente à Meticilina/genética , Antibacterianos/farmacologia , Agentes de Controle Biológico , Policetídeos/metabolismo , Família Multigênica
8.
iScience ; 26(10): 107809, 2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-37744031

RESUMO

Knowledge about the impact of different dissolved oxygen (DO) on the composition and function of gut bacteria of aquatic insects is largely unknown. Herein, we constructed freshwater environments with different DOs (hypoxia: 2.50 ± 0.50, normoxia: 7.00 ± 0.50, and hyperoxia: 13.00 ± 0.50 mg/L) where aquatic firefly Aquatica leii larvae lived for three months. Their gut flora was analyzed using the combination of 16S rRNA amplicon sequencing and metagenomics. The results showed no difference in alpha diversity of the gut flora between A. leii inhabiting various DOs. However, the relative abundance of several bacterial lineages presented significant changes, such as Pseudomonas. In addition, bacterial genes with an altered relative abundance in response to various DOs were primarily related to metabolism. The alteration of these functions correlated with the DO change. This is the first to uncover structure of gut flora under various DOs in aquatic insect larvae.

9.
Nat Commun ; 14(1): 668, 2023 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-36750564

RESUMO

Systemic lupus erythematosus is a heritable autoimmune disease that predominantly affects young women. To improve our understanding of genetic etiology, we conduct multi-ancestry and multi-trait meta-analysis of genome-wide association studies, encompassing 12 systemic lupus erythematosus cohorts from 3 different ancestries and 10 genetically correlated autoimmune diseases, and identify 16 novel loci. We also perform transcriptome-wide association studies, computational drug repurposing analysis, and cell type enrichment analysis. We discover putative drug classes, including a histone deacetylase inhibitor that could be repurposed to treat lupus. We also identify multiple cell types enriched with putative target genes, such as non-classical monocytes and B cells, which may be targeted for future therapeutics. Using this newly assembled result, we further construct polygenic risk score models and demonstrate that integrating polygenic risk score with clinical lab biomarkers improves the diagnostic accuracy of systemic lupus erythematosus using the Vanderbilt BioVU and Michigan Genomics Initiative biobanks.


Assuntos
Doenças Autoimunes , Lúpus Eritematoso Sistêmico , Humanos , Feminino , Estudo de Associação Genômica Ampla , Predisposição Genética para Doença , Fenótipo , Polimorfismo de Nucleotídeo Único
10.
Nat Genet ; 55(2): 291-300, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36702996

RESUMO

Most transcriptome-wide association studies (TWASs) so far focus on European ancestry and lack diversity. To overcome this limitation, we aggregated genome-wide association study (GWAS) summary statistics, whole-genome sequences and expression quantitative trait locus (eQTL) data from diverse ancestries. We developed a new approach, TESLA (multi-ancestry integrative study using an optimal linear combination of association statistics), to integrate an eQTL dataset with a multi-ancestry GWAS. By exploiting shared phenotypic effects between ancestries and accommodating potential effect heterogeneities, TESLA improves power over other TWAS methods. When applied to tobacco use phenotypes, TESLA identified 273 new genes, up to 55% more compared with alternative TWAS methods. These hits and subsequent fine mapping using TESLA point to target genes with biological relevance. In silico drug-repurposing analyses highlight several drugs with known efficacy, including dextromethorphan and galantamine, and new drugs such as muscle relaxants that may be repurposed for treating nicotine addiction.


Assuntos
Reposicionamento de Medicamentos , Transcriptoma , Humanos , Transcriptoma/genética , Estudo de Associação Genômica Ampla/métodos , Uso de Tabaco , Biologia , Polimorfismo de Nucleotídeo Único/genética , Predisposição Genética para Doença
11.
Front Immunol ; 14: 1315602, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38268924

RESUMO

Introduction: There is insufficient understanding on systemic interferon (IFN) responses during COVID-19 infection. Early reports indicated that interferon responses were suppressed by the coronavirus (SARS-CoV-2) and clinical trials of administration of various kinds of interferons had been disappointing. Expression of interferon-stimulated genes (ISGs) in peripheral blood (better known as interferon score) has been a well-established bioassay marker of systemic IFN responses in autoimmune diseases. Therefore, with archival samples of a cohort of COVID-19 patients collected before the availability of vaccination, we aimed to better understand this innate immune response by studying the IFN score and related ISGs expression in bulk and single cell RNAs sequencing expression datasets. Methods: In this study, we recruited 105 patients with COVID-19 and 30 healthy controls in Hong Kong. Clinical risk factors, disease course, and blood sampling times were recovered. Based on a set of five commonly used ISGs (IFIT1, IFIT2, IFI27, SIGLEC1, IFI44L), the IFN score was determined in blood leukocytes collected within 10 days after onset. The analysis was confined to those blood samples collected within 10 days after disease onset. Additional public datasets of bulk gene and single cell RNA sequencing of blood samples were used for the validation of IFN score results. Results: Compared to the healthy controls, we showed that ISGs expression and IFN score were significantly increased during the first 10 days after COVID infection in majority of patients (71%). Among those low IFN responders, they were more commonly asymptomatic patients (71% vs 25%). 22 patients did not mount an overall significant IFN response and were classified as low IFN responders (IFN score < 1). However, early IFN score or ISGs level was not a prognostic biomarker and could not predict subsequent disease severity. Both IFI27 and SIGLEC1 were monocyte-predominant expressing ISGs and IFI27 were activated even among those low IFN responders as defined by IFN score. In conclusion, a substantial IFN response was documented in this cohort of COVID-19 patients who experience a natural infection before the vaccination era. Like innate immunity towards other virus, the ISGs activation was observed largely during the early course of infection (before day 10). Single-cell RNA sequencing data suggested monocytes were the cell-type that primarily accounted for the activation of two highly responsive ISGs (IFI44L and IFI27). Discussion: As sampling time and age were two major confounders of ISG expression, they may account for contradicting observations among previous studies. On the other hand, the IFN score was not associated with the severity of the disease.


Assuntos
COVID-19 , Vacinas , Humanos , Interferons/genética , COVID-19/genética , SARS-CoV-2 , Imunidade Inata/genética
12.
Nature ; 612(7941): 720-724, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36477530

RESUMO

Tobacco and alcohol use are heritable behaviours associated with 15% and 5.3% of worldwide deaths, respectively, due largely to broad increased risk for disease and injury1-4. These substances are used across the globe, yet genome-wide association studies have focused largely on individuals of European ancestries5. Here we leveraged global genetic diversity across 3.4 million individuals from four major clines of global ancestry (approximately 21% non-European) to power the discovery and fine-mapping of genomic loci associated with tobacco and alcohol use, to inform function of these loci via ancestry-aware transcriptome-wide association studies, and to evaluate the genetic architecture and predictive power of polygenic risk within and across populations. We found that increases in sample size and genetic diversity improved locus identification and fine-mapping resolution, and that a large majority of the 3,823 associated variants (from 2,143 loci) showed consistent effect sizes across ancestry dimensions. However, polygenic risk scores developed in one ancestry performed poorly in others, highlighting the continued need to increase sample sizes of diverse ancestries to realize any potential benefit of polygenic prediction.


Assuntos
Consumo de Bebidas Alcoólicas , Predisposição Genética para Doença , Variação Genética , Internacionalidade , Herança Multifatorial , Uso de Tabaco , Humanos , Predisposição Genética para Doença/genética , Variação Genética/genética , Estudo de Associação Genômica Ampla/métodos , Herança Multifatorial/genética , Fatores de Risco , Uso de Tabaco/genética , Consumo de Bebidas Alcoólicas/genética , Transcriptoma , Tamanho da Amostra , Loci Gênicos/genética , Europa (Continente)/etnologia
13.
Chem Asian J ; 17(22): e202200740, 2022 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-36070227

RESUMO

Cancer is one of the most intractable diseases in the world because of its high recurrence rate, high metastasis rate and high lethality rate. Traditional chemotherapy, radiotherapy and surgery have unsatisfactory therapeutic effects and cause many severe side effects at the same time. Hydrogel is a new type of biomaterial with the advantages of good biocompatibility and easy degradation, which can be used as a carrier of functional nanomaterials for tumor therapy. Herein, we represent the progress of hydrogels with different skeletons and their application as carrier in tumor treatment. The hydrogels are listed as polyethylene glycol-based hydrogels, chitosan-based hydrogels, peptide-based hydrogels, hyaluronic acid-based hydrogels, steroid-based hydrogels and other hydrogels by skeletons, and their properties, modifications and toxicities were introduced. Some representative applications of combined hydrogels with nanomaterial for chemotherapy, photodynamic therapy, photothermal therapy, sonodynamic therapy, chemodynamic therapy and synergistic therapy are highlighted.


Assuntos
Quitosana , Neoplasias , Humanos , Hidrogéis , Ácido Hialurônico , Materiais Biocompatíveis , Neoplasias/tratamento farmacológico
14.
Angew Chem Int Ed Engl ; 61(35): e202203591, 2022 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-35689369

RESUMO

Nonribosomal peptide synthetases (NRPSs) can incorporate nonproteinogenic amino acids into peptidyl backbones to increase structural diversity. Genome mining of Schlegelella brevitalea led to the identification of a class of linear lipoheptapeptides, glidomides, featuring two unusual residues: threo-ß-OH-L-His and threo-ß-OH-D-Asp. The ß-hydroxylation of Asp and His is catalyzed by the nonheme FeII /α-ketoglutarate-dependent ß-hydroxylases GlmD and GlmF, respectively. GlmD independently catalyzes the hydroxylation of L-Asp to primarily produce threo-ß-OH-L-Asp on the thiolation domain, and then undergoes epimerization to form threo-ß-OH-D-Asp in the final products. However, ß-hydroxylation of His requires the concerted action of GlmF and the interface (I) domain, a novel condensation domain family clade. The key sites of I domain for interaction with GlmF were identified, suggesting that the mechanism for hydroxylation of His depends on the collaboration between hydroxylase and NRPS.


Assuntos
Aminoácidos , Peptídeo Sintases , Aminoácidos/metabolismo , Ácido Aspártico/metabolismo , Hidroxilação , Oxigenases de Função Mista/metabolismo , Peptídeo Sintases/metabolismo
15.
J Trace Elem Med Biol ; 72: 126992, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35550984

RESUMO

OBJECTIVE: Previous studies found that arsenic exposures have been linked to prostate cancer risk. However, this finding has been inconsistent. The purpose of this paper was to estimate the effects of arsenic exposures on prostate cancer risk. METHOD: We conducted a meta-analysis of epidemiologic studies of arsenic exposures and prostate cancer risk. We searched for both arsenic exposure and prostate cancer studies published until January 2021 from the following electronic databases: PubMed, Scopus, and Web of Science. Multilevel meta-analysis via random-effects modeling was used to examine the association between arsenic exposures and prostate cancer risk. RESULTS: There were 12 studies included with an effect size of 23. Arsenic exposure was determined from water and soil (n = 8), urinary measurements (n = 2), or self-reported questionnaire (n = 2). Overall, arsenic exposure was found to be statistically significantly associated with prostate cancer risk (Relative risk [RR] = 1.18, 95% confidence interval [CI]: 1.06 - 1.30). In the sub-analysis, arsenic exposure from water and soil was found to be statistically significantly associated with prostate cancer risk (RR= 1.22, 95% CI: 1.05 - 1.41). CONCLUSION: Data suggest that arsenic exposures may play a role in increasing prostate cancer risk. Further prospective studies are warranted to verify the association between arsenic exposure and prostate cancer risk.


Assuntos
Arsênio , Neoplasias da Próstata , Arsênio/análise , Arsênio/toxicidade , Humanos , Masculino , Estudos Prospectivos , Neoplasias da Próstata/induzido quimicamente , Neoplasias da Próstata/epidemiologia , Solo , Água
16.
Small ; 18(13): e2107160, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35146899

RESUMO

Emerging noninvasive treatments, such as sonodynamic therapy (SDT) and chemodynamic therapy (CDT), have developed as promising alternatives or supplements to traditional chemotherapy. However, their therapeutic effects are limited by the hypoxic environment of tumors. Here, a biodegradable nanocomposite-mesoporous zeolitic-imidazolate-framework@MnO2 /doxorubicin hydrochloride (mZMD) is developed, which achieves enhanced SDT/CDT/chemotherapy through promoting oxidative stress and overcoming the multidrug resistance. The mZMD decomposes under both ultrasound (US) irradiation and specific reactions in the tumor microenvironment (TME). The mZM composite structure reduces the recombination rate of e- and h+ to improve SDT. MnO2 not only oxidizes glutathione in tumor cells to enhance oxidative stress, but also converts the endogenic H2 O2 into O2 to improve the hypoxic TME, which enhances the effects of chemotherapy/SDT. Meanwhile, the generated Mn2+ catalyzes the endogenic H2 O2 into ·OH for CDT, and acts as magnetic resonance imaging agent to guide therapy. In addition, dissociated Zn2+ further breaks the redox balance of TME, and co-inhibits the expression of P-glycoprotein (P-gp) with generated ROS to overcome drug resistance. Thus, the as-prepared intelligent biodegradable mZMD provides an innovative strategy to enhance SDT/CDT/chemotherapy.


Assuntos
Compostos de Manganês , Óxidos , Linhagem Celular Tumoral , Resistência a Múltiplos Medicamentos , Estresse Oxidativo , Óxidos/química , Microambiente Tumoral
17.
J Mater Chem B ; 10(4): 637-645, 2022 01 26.
Artigo em Inglês | MEDLINE | ID: mdl-34991154

RESUMO

Chemodynamic therapy (CDT) is an emerging approach to treat cancer based on the tumor microenvironment (TME), but its limited content of endogenous hydrogen peroxide (H2O2) weakens the anticancer effects. Herein, a multifunctional biomimetic nanozyme (Se@SiO2-Mn@Au/DOX, named as SSMA/DOX) is fabricated, which undergoes TME responsive self-cascade catalysis to facilitate MRI guided enhanced chemo/chemodynamic therapy. The SSMA/DOX nanocomposites (NCs) responsively degrade in acidic conditions of tumor to release Se, DOX, Au and Mn2+. Mn2+ not only enables MRI to guided therapy, but also catalyzes the endogenous H2O2 into hydroxyl radical (˙OH) for CDT. In addition, the Au NPs continuously catalyze glucose to generate H2O2, enhancing CDT by supplementing a sufficiently reactive material and cutting off the energy supply of the tumor by consuming glucose. Simultaneously, Se enhances the chemotherapy of doxorubicin hydrochloride (DOX) and CDT by upregulating ROS in the tumor cells, achieving remarkable inhibition effect towards tumor. Moreover, SSMA/DOX NCs have good biocompatibility and degradability, which avoid long-term toxicity and side effects. Overall, the degradable SSMA/DOX NCs provide an innovative strategy for tumor microenvironment responsive self-cascade catalysis to enhance tumor therapy.


Assuntos
Antineoplásicos/farmacologia , Doxorrubicina/farmacologia , Terapia Fototérmica , Neoplasias do Colo do Útero/tratamento farmacológico , Animais , Antineoplásicos/química , Materiais Biomiméticos/química , Materiais Biomiméticos/farmacologia , Catálise , Linhagem Celular , Doxorrubicina/química , Feminino , Ouro/química , Ouro/farmacologia , Humanos , Manganês/química , Manganês/farmacologia , Teste de Materiais , Ratos , Ratos Sprague-Dawley , Selênio/química , Selênio/farmacologia , Dióxido de Silício/química , Dióxido de Silício/farmacologia , Microambiente Tumoral/efeitos dos fármacos
18.
J Nanobiotechnology ; 19(1): 382, 2021 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-34809618

RESUMO

BACKGROUND: Inflammatory osteolysis, a major complication of total joint replacement surgery, can cause prosthesis failure and necessitate revision surgery. Macrophages are key effector immune cells in inflammatory responses, but excessive M1-polarization of dysfunctional macrophages leads to the secretion of proinflammatory cytokines and severe loss of bone tissue. Here, we report the development of macrophage-biomimetic porous SiO2-coated ultrasmall Se particles (porous Se@SiO2 nanospheres) to manage inflammatory osteolysis. RESULTS: Macrophage membrane-coated porous Se@SiO2 nanospheres(M-Se@SiO2) attenuated lipopolysaccharide (LPS)-induced inflammatory osteolysis via a dual-immunomodulatory effect. As macrophage membrane decoys, these nanoparticles reduced endotoxin levels and neutralized proinflammatory cytokines. Moreover, the release of Se could induce macrophage polarization toward the anti-inflammatory M2-phenotype. These effects were mediated via the inhibition of p65, p38, and extracellular signal-regulated kinase (ERK) signaling. Additionally, the immune environment created by M-Se@SiO2 reduced the inhibition of osteogenic differentiation caused by proinflammation cytokines, as confirmed through in vitro and in vivo experiments. CONCLUSION: Our findings suggest that M-Se@SiO2 have an immunomodulatory role in LPS-induced inflammation and bone remodeling, which demonstrates that M-Se@SiO2 are a promising engineered nanoplatform for the treatment of osteolysis occurring after arthroplasty.


Assuntos
Materiais Biomiméticos , Fatores Imunológicos , Macrófagos , Nanocompostos/química , Osteólise/metabolismo , Animais , Materiais Biomiméticos/química , Materiais Biomiméticos/farmacologia , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/farmacologia , Citocinas/metabolismo , Modelos Animais de Doenças , Fatores Imunológicos/química , Fatores Imunológicos/farmacologia , Imunoterapia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos , Porosidade , Células RAW 264.7 , Selênio/química , Selênio/farmacologia , Dióxido de Silício/química , Dióxido de Silício/farmacologia
19.
Nutrients ; 13(7)2021 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-34371826

RESUMO

BACKGROUND: Sarcopenia is a major health problem in older adults. Exercise and nutrient supplementation have been shown to be effective interventions but there are limited studies to investigate their effects on the management of sarcopenia and its possible underlying mechanisms. Here, we studied T cell gene expression responses to interventions in sarcopenia. METHODS: The results of this study were part of a completed trial examining the effectiveness of a 12-week intervention with exercise and nutrition supplementation in community-dwelling Chinese older adults with sarcopenia, based on the available blood samples at baseline and 12 weeks from 46 randomized participants from three study groups, namely: exercise program alone (n = 11), combined-exercise program and nutrition supplement (n = 23), and waitlist control group (n = 12). T cell gene expression was evaluated, with emphasis on inflammation-related genes. Real-time PCR (RT-PCR) was performed on CD3 T cells in 38 selected genes. Correlation analysis was performed to relate the results of gene expression analysis with lower limb muscle strength performance, measured using leg extension tests. RESULTS: Our results showed a significant improvement in leg extension for both the exercise program alone and the combined groups (p < 0.001). Nine genes showed significant pre- and post-difference in gene expression over 12 weeks of intervention in the combined group. Seven genes (RASGRP1, BIN1, LEF1, ANXA6, IL-7R, LRRN3, and PRKCQ) showed an interaction effect between intervention and gene expression levels on leg extension in the confirmatory analysis, with confounder variables controlled and FDR correction. CONCLUSIONS: Our findings showed that T cell-specific inflammatory gene expression was changed significantly after 12 weeks of intervention with combined exercise and HMB supplementation in sarcopenia, and that this was associated with lower limb muscle strength performance.


Assuntos
Suplementos Nutricionais , Exercício Físico/fisiologia , Expressão Gênica/genética , Sarcopenia/terapia , Linfócitos T/metabolismo , Valeratos/administração & dosagem , Idoso , Idoso de 80 Anos ou mais , Terapia Combinada , Análise Fatorial , Feminino , Humanos , Vida Independente , Extremidade Inferior/fisiopatologia , Masculino , Força Muscular/genética , Músculo Esquelético/fisiopatologia , Treinamento Resistido/métodos , Sarcopenia/genética , Resultado do Tratamento
20.
Adv Healthc Mater ; 10(10): e2002024, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33645002

RESUMO

Radiotherapy (RT) is a popular clinical therapy method for extending cancer patient survival, but is hampered by severe side effects and the weak therapy effect. Herein, responsive degradable selenium (Se) theranostic agents (Se@SiO2 @Bi nanocomposites (NCs)) are fabricated, which combine computed tomography (CT) imaging and simultaneously enhance the therapeutic effects of photothermal therapy (PTT) and RT, while reducing the side effects of radiation. The Se@SiO2 @Bi theranostic agents can accumulate at the tumor site, and responsively decompose to releease Se, avoiding systemic toxicity by the element. Se enhances the effect of PTT/RT, simultaneously reducing the side effects of RT. The Se@SiO2 @Bi NCs as CT agents also exhibit significantly enhanced contrast imaging performance due to the high atomic number of Bi. More importantly, the Se@SiO2 @Bi NCs can be rapidly excreted without long-term toxicity, owing to responsive degradation into ultrasmall particles (<5 nm) at the tumor site. In vitro and in vivo results show that the Se@SiO2 @Bi NCs can remarkably inhibit tumor cells, without causing appreciable toxicity during the treatment. This study opens a new perspective in rationally designing responsive degradable theranostic agents for future tumor therapy with enhanced therapeutic efficacy and lesser side effects.


Assuntos
Nanocompostos , Selênio , Humanos , Fototerapia , Medicina de Precisão , Dióxido de Silício , Nanomedicina Teranóstica
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