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1.
J Chem Phys ; 160(20)2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38775745

RESUMO

The understanding on the growth mechanism of complex gold nanostructures both experimentally and theoretically can guide their design and fabrication toward various applications. In this work, we report a cysteine-directed overgrowth of penta-twinned nanorod seeds into jagged gold bipyramids with discontinuous stepped {hhk} facets. By monitoring the growth process, we find that {hhk} facets with large k/h values (∼7) are formed first at two ends of the nanorods, followed by the protrusion of the middle section exposing {hhk} facets with smaller indices (k/h ∼ 2-3). Molecular dynamics simulations indicate that the strong adsorption of cysteine molecules on {110} facets is likely responsible for the formation of stepped {hhk} facets, and the stronger adsorption of cysteine molecules on {hhk} facets with smaller k/h compared to that on {hhk} facets with larger k/h is a possible cause of the discontinuity of {hhk} facets at the middle of gold bipyramids. The obtained jagged gold bipyramids display large field enhancement under illumination due to their sharp nanostructures, demonstrating their application potentials in surface-enhanced spectroscopy and catalysis.

2.
J Org Chem ; 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38767586

RESUMO

Patumantanes A-D (1-4), four new seco-polycyclic polyprenylated acylphloroglucinols (PPAPs) were isolated from Hypericum patulum. Patumantane A (1) was an unprecedented 1,2-seco-homoadamantane-type PPAP bearing a new 3,7-dioxatetracyclo[7.7.0.01,6.111,15]heptadecane architecture based on a 6/7/5/6 ring system. Patumantane B (2) was a unique 1,9-seco-adamantane-type PPAP with a tricyclo[4.4.4.0.02,12]tridecane core formed by a 6/6/6 carbon skeleton, and the further breakage between C-5 and C-9 decorated patumantane C (3) with the 9-nor-adamantane skeleton. More importantly, compounds 2 and 3 exhibited moderate immunosuppressive activity on Con A-induced T-lymphocyte proliferation in vitro, with IC50 values of 5.6 ± 1.2 and 11.2 ± 1.2 µM, respectively.

3.
World J Surg Oncol ; 22(1): 94, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38610000

RESUMO

BACKGROUND: Temporary ileostomy (TI) has proven effective in reducing the severity of anastomotic leakage after rectal cancer surgery; however, some ileostomies fail to reverse over time, leading to conversion into a permanent stoma (PS). In this study, we aimed to investigate the preoperative risk factors and cumulative incidence of TI non-closure after sphincter-preserving surgery for rectal cancer. MATERIALS AND METHODS: We conducted a meta-analysis after searching the Embase, Web of Science, PubMed, and MEDLINE databases from their inception until November 2023. We collected all published studies on the risk factors related to TI non-closure after sphincter-preserving surgery for rectal cancer. RESULTS: A total of 1610 studies were retrieved, and 13 studies were included for meta-analysis, comprising 3026 patients. The results of the meta-analysis showed that the identified risk factors included older age (p = 0.03), especially > 65 years of age (p = 0.03), male sex (p = 0.009), American Society of Anesthesiologists score ≥ 3 (p = 0.004), comorbidity (p = 0.001), and distant metastasis (p < 0.001). Body mass index, preoperative hemoglobin, preoperative albumin, preoperative carcinoma embryonic antigen, tumor location, neoadjuvant chemoradiotherapy, smoking, history of abdominal surgery, and open surgery did not significantly change the risk of TI non-closure. CONCLUSION: We identified five preoperative risk factors for TI non-closure after sphincter-preserving surgery for rectal cancer. This information enables surgeons to identify high-risk groups before surgery, inform patients about the possibility of PS in advance, and consider performing protective colostomy or Hartmann surgery.


Assuntos
Neoplasias Retais , Estomas Cirúrgicos , Humanos , Masculino , Ileostomia/efeitos adversos , Incidência , Fatores de Risco , Neoplasias Retais/cirurgia
4.
Front Bioeng Biotechnol ; 12: 1382085, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38572358

RESUMO

In this study, a high-efficiency superparamagnetic drug delivery system was developed for preclinical treatment of bladder cancer in small animals. Two types of nanoparticles with magnetic particle imaging (MPI) capability, i.e., single- and multi-core superparamagnetic iron oxide nanoparticles (SPIONs), were selected and coupled with bladder anti-tumor drugs by a covalent coupling scheme. Owing to the minimal particle size, magnetic field strengths of 270 mT with a gradient of 3.2 T/m and 260 mT with a gradient of 3.7 T/m were found to be necessary to reach an average velocity of 2 mm/s for single- and multi-core SPIONs, respectively. To achieve this, a method of constructing an in vitro magnetic field for drug delivery was developed based on hollow multi-coils arranged coaxially in close rows, and magnetic field simulation was used to study the laws of the influence of the coil structure and parameters on the magnetic field. Using this method, a magnetic drug delivery system of single-core SPIONs was developed for rabbit bladder therapy. The delivery system consisted of three coaxially and equidistantly arranged coils with an inner diameter of Φ50 mm, radial height of 85 mm, and width of 15 mm that were positioned in close proximity to each other. CCK8 experimental results showed that the three types of drug-coupled SPION killed tumor cells effectively. By adjusting the axial and radial positions of the rabbit bladder within the inner hole of the delivery coil structure, the magnetic drugs injected could undergo two-dimensional delivery motions and were delivered and aggregated to the specified target location within 12 s, with an aggregation range of about 5 mm × 5 mm. In addition, the SPION distribution before and after delivery was imaged using a home-made open-bore MPI system that could realistically reflect the physical state. This study contributes to the development of local, rapid, and precise drug delivery and the visualization of this process during cancer therapy, and further research on MPI/delivery synchronization technology is planned for the future.

5.
Exp Brain Res ; 242(6): 1387-1397, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38563979

RESUMO

Cerebral small vessel disease (CSVD) is increasingly being recognized as a leading contributor to cognitive impairment in the elderly. However, there is a lack of effective preventative or therapeutic options for CSVD. In this exploratory study, we investigated the interplay between neuroinflammation and CSVD pathogenesis as well as the cognitive performance, focusing on NLRP3 signaling as a new therapeutic target. Spontaneously hypertensive stroke-prone (SHRSP) rats served as a CSVD model. We found that SHRSP rats showed decline in learning and memory abilities using morris water maze test. Activated NLRP3 signaling and an increased expression of the downstream pro-inflammatory factors, including IL (interleukin)-6 and tumor necrosis factor α were determined. We also observed a remarkable increase in the production of pyroptosis executive protein gasdermin D, and elevated astrocytic and microglial activation. In addition, we identify several neuropathological hallmarks of CSVD, including blood-brain barrier breakdown, white matter damage, and endothelial dysfunction. These results were in correlation with the activation of NLRP3 inflammasome. Thus, our findings reveal that the NLRP3-mediated inflammatory pathway could play a central role in the pathogenesis of CSVD, presenting a novel target for potential CSVD treatment.


Assuntos
Doenças de Pequenos Vasos Cerebrais , Modelos Animais de Doenças , Inflamassomos , Proteína 3 que Contém Domínio de Pirina da Família NLR , Ratos Endogâmicos SHR , Animais , Doenças de Pequenos Vasos Cerebrais/metabolismo , Doenças de Pequenos Vasos Cerebrais/patologia , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Ratos , Inflamassomos/metabolismo , Masculino , Doenças Neuroinflamatórias/metabolismo , Microglia/metabolismo , Barreira Hematoencefálica/metabolismo , Barreira Hematoencefálica/patologia , Transdução de Sinais/fisiologia
6.
Front Microbiol ; 15: 1353710, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38511011

RESUMO

Introduction: Cordyceps cicadae is a traditional Chinese medicinal fungus known for its rich production of bioactive substances, particularly cyanidin, an anthocyanin commonly found in plants with notable anti-inflammatory, anti-tumor, antiviral, and antibacterial properties. This study revealed two key genes, CcDFR and CcOMT9, affecting cyanidin biosynthesis in C. cicadae. Methods: The roles of these genes in cyanidin production, growth, and development were elucidated through the gene knockout method, phenotypic analysis, transcriptomics, and metabolomics. Results: CcDFR deletion led to reduced cyanidin-3-O-glucoside (C3G), suppressed expression of cyanidin biosynthesis genes, impaired synnemata formation, decreased polysaccharide and adenosine content, and diminished chitinase activity. Meanwhile, the ΔCcOMT9 mutant exhibited an increase in C3G production, promoted expression of cyanidin biosynthesis genes and rising bioactive compounds, suppressed RNA methylation, and led to phenylalanine accumulation with no effect on fruiting body formation. Discussion: We revealed a distinct anthocyanin biosynthesis pathway in C. cicadae and identified two genes with opposite functions, laying the foundation for future genetic modification of cyanidin-producing strains using modern biological techniques. This will shorten the production period of this valuable compound, facilitating the industrial-scale production of cyanidin.

7.
ACS Nano ; 18(14): 10142-10155, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38526307

RESUMO

Fully mobilizing the activities of multiple immune cells is crucial to achieve the desired tumor immunotherapeutic efficacy yet still remains challenging. Herein, we report a nanomedicine formulation based on phosphorus dendrimer (termed AK128)/programmed cell death protein 1 antibody (aPD1) nanocomplexes (NCs) that are camouflaged with M1-type macrophage cell membranes (M1m) for enhanced immunotherapy of orthotopic glioma. The constructed AK128-aPD1@M1m NCs with a mean particle size of 160.3 nm possess good stability and cytocompatibility. By virtue of the decorated M1m having α4 and ß1 integrins, the NCs are able to penetrate the blood-brain barrier to codeliver both AK128 with intrinsic immunomodulatory activity and aPD1 to the orthotopic glioma with prolonged blood circulation time. We show that the phosphorus dendrimer AK128 can boost natural killer (NK) cell proliferation in peripheral blood mononuclear cells, while the delivered aPD1 enables immune checkpoint blockade (ICB) to restore the cytotoxic T cells and NK cells, thus promoting tumor cell apoptosis and simultaneously decreasing the tumor distribution of regulatory T cells vastly for improved glioma immunotherapy. The developed nanomedicine formulation with a simple composition achieves multiple modulations of immune cells by utilizing the immunomodulatory activity of nanocarrier and antibody-mediated ICB therapy, providing an effective strategy for cancer immunotherapy.


Assuntos
Dendrímeros , Glioma , Humanos , Fósforo , Leucócitos Mononucleares/metabolismo , Leucócitos Mononucleares/patologia , Biomimética , Glioma/terapia , Glioma/patologia , Imunoterapia , Células Matadoras Naturais , Anticorpos/metabolismo , Linfócitos T Citotóxicos , Barreira Hematoencefálica/metabolismo , Microambiente Tumoral
8.
Sci Total Environ ; 922: 171325, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38428604

RESUMO

Despite the well-established recognition of the health hazards posed by PM2.5-bound PAHs, a comprehensive understanding of their source-specific impact has been lacking. In this study, the health risks associated with PM2.5-bound polycyclic aromatic hydrocarbons (PAHs) and source-specific contributions were investigated in the urban region of Taipei during both cold and warm seasons. The levels of PM2.5-bound PAHs and their potential health risks across different age groups of humans were also characterized. Diagnostic ratios and positive matrix factorization analysis were utilized to identify the sources of PM2.5-bound PAHs. Moreover, potential source contribution function (PSCF), concentration-weighted trajectory (CWT) and source regional apportionment (SRA) analyses were employed to determine the potential source regions. Results showed that the total PAHs (TPAHs) concentrations ranged from 0.08 to 2.37 ng m-3, with an average of 0.69 ± 0.53 ng m-3. Vehicular emissions emerged as the primary contributor to PM2.5-bound PAHs, constituting 39.8 % of the TPAHs concentration, followed by industrial emissions (37.6 %), biomass burning (13.8 %), and petroleum/oil volatilization (8.8 %). PSCF and CWT analyses revealed that industrial activities and shipping processes in northeast China, South China Sea, Yellow Sea, and East China Sea, contributed to the occurrence of PM2.5-bound PAHs in Taipei. SRA identified central China as the primary regional contributor of ambient TPAHs in the cold season and Taiwan in the warm season, respectively. Evaluations of incremental lifetime cancer risk demonstrated the highest risk for adults, followed by children, seniors, and adolescents. The assessments of lifetime lung cancer risk showed that vehicular and industrial emissions were the main contributors to cancer risk induced by PM2.5-bound PAHs. This research emphasizes the essential role of precisely identifying the origins of PM2.5-bound PAHs to enhance our comprehension of the related human health hazards, thus providing valuable insights into the mitigation strategies.


Assuntos
Poluentes Atmosféricos , Neoplasias Pulmonares , Hidrocarbonetos Policíclicos Aromáticos , Criança , Humanos , Adolescente , Poluentes Atmosféricos/análise , Estações do Ano , Material Particulado/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Monitoramento Ambiental/métodos , China , Ásia Oriental , Medição de Risco
9.
Biochem Biophys Res Commun ; 707: 149513, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38508051

RESUMO

Cancer is a significant global health concern, and finding effective methods to treat it has been a focus of scientific research. It has been discovered that the growth, invasion, and metastasis of tumors are closely related to the environment in which they exist, known as the tumor microenvironment (TME). The immune response interacting with the tumor occurring within the TME constitutes the tumor immune microenvironment, and the immune response can lead to anti-tumor and pro-tumor outcomes and has shown tremendous potential in immunotherapy. A channel called the P2X7 receptor (P2X7R) has been identified within the TME. It is an ion channel present in various immune cells and tumor cells, and its activation can lead to inflammation, immune responses, angiogenesis, immunogenic cell death, and promotion of tumor development. This article provides an overview of the structure, function, and pharmacological characteristics of P2X7R. We described the concept and components of tumor immune microenvironment and the influence immune components has on tumors. We also outlined the impact of P2X7R regulation and how it affects the development of tumors and summarized the effects of drugs targeting P2X7R on tumor progression, both past and current, assisting researchers in treating tumors using P2X7R as a target.


Assuntos
Neoplasias , Receptores Purinérgicos P2X7 , Microambiente Tumoral , Humanos , Neoplasias/metabolismo , Receptores Purinérgicos P2X7/metabolismo , Animais
10.
Clin Transl Med ; 14(3): e1605, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38445456

RESUMO

BACKGROUND: Bone or brain metastases may develop in 20-40% of individuals with late-stage non-small-cell lung cancer (NSCLC), resulting in a median overall survival of only 4-6 months. However, the primary lung cancer tissue's distinctions between bone, brain and intrapulmonary metastases of NSCLC at the single-cell level have not been underexplored. METHODS: We conducted a comprehensive analysis of 14 tissue biopsy samples obtained from treatment-naïve advanced NSCLC patients with bone (n = 4), brain (n = 6) or intrapulmonary (n = 4) metastasis using single-cell sequencing originating from the lungs. Following quality control and the removal of doublets, a total of 80 084 cells were successfully captured. RESULTS: The most significant inter-group differences were observed in the fraction and function of fibroblasts. We identified three distinct cancer-associated fibroblast (CAF) subpopulations: myofibroblastic CAF (myCAF), inflammatory CAF (iCAF) and antigen-presenting CAF (apCAF). Notably, apCAF was prevalent in NSCLC with bone metastasis, while iCAF dominated in NSCLC with brain metastasis. Intercellular signalling network analysis revealed that apCAF may play a role in bone metastasis by activating signalling pathways associated with cancer stemness, such as SPP1-CD44 and SPP1-PTGER4. Conversely, iCAF was found to promote brain metastasis by activating invasion and metastasis-related molecules, such as MET hepatocyte growth factor. Furthermore, the interaction between CAFs and tumour cells influenced T-cell exhaustion and signalling pathways within the tumour microenvironment. CONCLUSIONS: This study unveils the direct interplay between tumour cells and CAFs in NSCLC with bone or brain metastasis and identifies potential therapeutic targets for inhibiting metastasis by disrupting these critical cell-cell interactions.


Assuntos
Neoplasias Encefálicas , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Encéfalo , Fibroblastos , Microambiente Tumoral
11.
Can J Gastroenterol Hepatol ; 2024: 2410643, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38550348

RESUMO

Background: Protective ileostomy can effectively prevent severe anastomotic leakage after rectal cancer surgery; however, the optimal timing for ileostomy closure during adjuvant chemotherapy remains unclear. This study aimed to explore the safety and long-term outcomes of early ileostomy closure during adjuvant chemotherapy. Method: Patients who underwent laparoscopic rectal cancer surgery combined with protective ileostomy and adjuvant chemotherapy between April 2017 and April 2021 were retrospectively evaluated. Patients were divided into an early closure group during chemotherapy (group A) and a late closure group after chemotherapy (group B). Results: A total of 215 patients were included in this study, with 115 in group A and 100 in group B. There were no significant differences in demographic and clinical characteristics between the two groups. In group A, durations of stoma status (p < 0.001) and low anterior resection syndrome (LARS) (p < 0.001) were shorter, and rectal stenosis (p=0.036) and stoma-related complications (p=0.007), especially stoma stenosis (p=0.041), were less common. However, compliance with chemotherapy was worse (p=0.009). There were no significant differences in operative time, postoperative hospital stay, postoperative complications, incidence and severity of LARS, disease-free survival, or overall survival between groups. Conclusion: Early ileostomy closure can effectively reduce the duration of stoma status, duration of LARS, rectal stenosis, and stoma-related complications while not affecting surgical complications and oncological outcomes. Ileostomy closure should not be delayed because of adjuvant chemotherapy. However, follow-up should be strengthened to increase compliance and integrity with chemotherapy.


Assuntos
Ileostomia , Neoplasias Retais , Humanos , Ileostomia/efeitos adversos , Neoplasias Retais/tratamento farmacológico , Neoplasias Retais/cirurgia , Neoplasias Retais/complicações , Complicações Pós-Operatórias/etiologia , Estudos Retrospectivos , Constrição Patológica/complicações , Síndrome , Quimioterapia Adjuvante
12.
Front Oncol ; 14: 1320508, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38333683

RESUMO

Background: Laparoscopic right hemicolectomy is a standard treatment modality for right colon cancer. However, performing intracorporeal anastomosis (IA) for totally laparoscopic right hemicolectomy (TLRH) remains a challenge for some surgeons. To simplify IA in TLRH we used self-pulling and latter transection (SPLT) reconstruction in TLRH, and compared this procedure with overlap IA and laparoscopy-assisted right hemicolectomy (LARH) in order to evaluate its safety and effectiveness. Methods: Patients with right colon cancer who underwent SPLT-TLRH, TLRH with overlap IA or LARH between July 2019 and June 2023 were evaluated retrospectively. Basic information, oncological features, perioperative outcomes, and postoperative complications were compared between groups. Results: In total, 188 patients with right colon cancer that underwent SPLT-TLRH (n = 60), TLRH(n=21) or LARH (n = 107) were included in the study. No patient required conversion to open surgery. The operation time in SPLT-TLRH group was significantly shorter than that in TLRH group (P<0.05). Compared with LARH group, SPLT-TLRH group had significantly longer distal margins, shorter skin incisions (P < 0.001), time to first flatus, time to first defecation, and postoperative hospital stays (P<0.05). Conclusion: We introduced SPLT to TLRH. The SPLT-TLRH group demonstrated better short-term outcomes. Therefore, we believe that SPLT reconstruction is effective and safe in TLRH for right colon cancer, and can simplify reconstruction.

13.
Eur J Med Chem ; 268: 116252, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38422703

RESUMO

The modification based on natural products is a practical way to find anti-inflammatory drugs. In this study, 26 osthole derivatives were synthesized, and their anti-inflammatory properties were evaluated. The preliminary activity study revealed that most osthole derivatives could effectively inhibit inflammatory cytokines IL-6 secretion in LPS stimulated mouse macrophages J774A.1. Compound 7m exhibited the most effective anti-inflammatory activity (RAW264.7 IL-6 IC50: 4.57 µM, 32 times more active than osthole) in vitro with no significant influence on cell proliferation. Additionally, the mechanistic analysis demonstrated that compound 7m could block MAPK signal transduction by inhibiting the phosphorylation of JNK and p38, thereby inhibiting the release of inflammatory cytokines. Moreover, in vivo functional investigations revealed that 7m could substantially reduce DSS-induced ulcerative colitis and LPS-induced acute lung injury, with good therapeutic effects. The pharmacokinetics and acute toxicity experiments proved the safety and reliability of 7min vivo. Overall, Compound 7m could further be studied as potential anti-inflammatory candidate.


Assuntos
Lesão Pulmonar Aguda , Colite Ulcerativa , Colite , Cumarínicos , Animais , Camundongos , Colite Ulcerativa/induzido quimicamente , Colite Ulcerativa/tratamento farmacológico , Lipopolissacarídeos/farmacologia , Interleucina-6 , Reprodutibilidade dos Testes , Anti-Inflamatórios/efeitos adversos , Lesão Pulmonar Aguda/induzido quimicamente , Lesão Pulmonar Aguda/tratamento farmacológico , Citocinas , NF-kappa B , Camundongos Endogâmicos C57BL , Colite/tratamento farmacológico
14.
Cancer Lett ; 584: 216615, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38199586

RESUMO

The biological role of B7-H1 intrinsic signal is reportedly diverse and controversial, its signal pathway remains unclear. Although B7-H1 blocking antibodies were found to have agonist capacity, their binding features and agonist mechanisms need further investigation. Here, by constructing cell strains with full-length or truncated B7-H1, we found that B7-H1 functioned as a receptor to transmit cell death signal from PD-1 protein or anti-B7-H1s through its cytoplasmic domain. Specific binding to the IgV-like domain of B7-H1 was required for the downstream signal. Upon agonists interaction, B7-H1 regulated the degradation of phosphoinositide 3-kinases (PI3Ks) subunit p110γ, subsequently inhibited the PI3K/AKT/mTOR pathway, and significantly increased autophagy. Moreover, B7-H1 agonists also suppressed ubiquitylation in B7-H1+cells by reducing ubiquitin-activating enzyme (E1), eventually leading to cell death. Finally, we validated the receptor role of B7-H1 in multiple tumor cells and demonstrated that B7-H1 agonists could suppress tumor progression independent of T cells in vivo. Our findings revealed that B7-H1 agonists functions as a PI3K inhibitor and may offer new strategies for PI3K targeting therapy.


Assuntos
Fosfatidilinositol 3-Quinases , Proteínas Proto-Oncogênicas c-akt , Antígeno B7-H1/metabolismo , Morte Celular , Classe Ib de Fosfatidilinositol 3-Quinase , Agonistas dos Receptores Histamínicos , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Serina-Treonina Quinases TOR/metabolismo
15.
ACS Nano ; 18(3): 2195-2209, 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38194222

RESUMO

Nanocarrier-based cytoplasmic protein delivery offers opportunities to develop protein therapeutics; however, many delivery systems are positively charged, causing severe toxic effects. For enhanced therapeutics, it is also of great importance to design nanocarriers with intrinsic bioactivity that can be integrated with protein drugs due to the limited bioactivity of proteins alone for disease treatment. We report here a protein delivery system based on anionic phosphite-terminated phosphorus dendrimers with intrinsic anti-inflammatory activity. A phosphorus dendrimer termed AK-137 with optimized anti-inflammatory activity was selected to complex proteins through various physical interactions. Model proteins such as bovine serum albumin, ribonuclease A, ovalbumin, and fibronectin (FN) can be transfected into cells to exert their respective functions, including cancer cell apoptosis, dendritic cell maturation, or macrophage immunomodulation. Particularly, the constructed AK-137@FN nanocomplexes display powerful therapeutic effects in acute lung injury and acute gout arthritis models by integrating the anti-inflammatory activity of both the carrier and protein. The developed anionic phosphite-terminated phosphorus dendrimers may be employed as a universal carrier for protein delivery and particularly utilized to deliver proteins and fight different inflammatory diseases with enhanced therapeutic efficacy.


Assuntos
Dendrímeros , Fosfitos , Dendrímeros/farmacologia , Fósforo , Proteínas , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico
16.
Phys Chem Chem Phys ; 26(4): 3322-3334, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38197437

RESUMO

Chronic traumatic encephalopathy is a neurodegenerative tauopathy pathologically characterized by fibrillary tau aggregates in the depth of sulci. Clearing fibrous tau aggregates is considered a promising strategy in the treatment of CTE. Fisetin (FS), a natural polyphenolic small molecule, was confirmed to disassociate the tau filaments in vitro. However, the molecular mechanisms of FS in destabilizing the CTE-related R3-R4 tau fibrils remain largely unknown. In this study, we compared the atomic-level structural differences of the two types of CTE-related R3-R4 tau fibrils and explored the influence and molecular mechanisms of FS on the two types of fibrils by conducting multiple molecular dynamics (MD) simulations. The results reveal that the type 1 fibril displays higher structural stability than the type 2 fibril, with a lower root-mean-square-fluctuation value and higher ß-sheet structure probability. FS can destabilize both types of fibrils by decreasing the ß-sheet structure content, interrupting the mainchain H-bond network, and increasing the solvent accessible surface area and ß7-ß8 angle of the fibrils. H-bonding, π-π stacking and cation-π are the common interactions driving FS molecules binding on the two types of fibrils, while the hydrophobic interaction occurs only in the type 2 fibril. Due to the relatively short simulation time, our study captures the early molecular mechanisms. However, it does provide beneficial information for the design of drugs to prevent or treat CTE.


Assuntos
Doença de Alzheimer , Encefalopatia Traumática Crônica , Humanos , Encefalopatia Traumática Crônica/metabolismo , Proteínas tau/química , Flavonóis , Simulação de Dinâmica Molecular , Doença de Alzheimer/metabolismo
17.
Biomacromolecules ; 25(2): 1171-1179, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38181417

RESUMO

The development of nonviral dendritic polymers with a simple molecular backbone and great gene delivery efficiency to effectively tackle cancer remains a great challenge. Phosphorus dendrimers or dendrons are promising vectors due to their structural uniformity, rigid molecular backbones, and tunable surface functionalities. Here, we report the development of a new low-generation unsymmetrical cationic phosphorus dendrimer bearing 5 pyrrolidinium groups and one amino group as a nonviral gene delivery vector. The created AB5-type dendrimers with simple molecular backbone can compress microRNA-30d (miR-30d) to form polyplexes with desired hydrodynamic sizes and surface potentials and can effectively transfect miR-30d to cancer cells to suppress the glycolysis-associated SLC2A1 and HK1 expression, thus significantly inhibiting the migration and invasion of a murine breast cancer cell line in vitro and the corresponding subcutaneous tumor mouse model in vivo. Such unsymmetrical low-generation phosphorus dendrimers may be extended to deliver other genetic materials to tackle other diseases.


Assuntos
Dendrímeros , MicroRNAs , Neoplasias , Animais , Camundongos , Dendrímeros/química , Vetores Genéticos , MicroRNAs/genética , Técnicas de Transferência de Genes , Cátions , Fósforo
18.
Biophys Chem ; 305: 107142, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38088006

RESUMO

Inhibiting tau protein aggregation has become a prospective avenue for the therapeutic development of tauopathies. The third microtubule-binding repeat (R3) domain of tau is confirmed as the most aggregation-favorable fragment of the whole protein. As dimerization is the first step of the aggregation of tau into amyloid fibrils, impeding the dimerization of the R3 domain is critical to prevent the full-length tau aggregation. Natural polyphenol small molecules epigallocatechin gallate (EGCG), quercetin (QE) and gallic acid (GA) are proven to inhibit the aggregation of the full-length recombinant tau (For EGCG and QE) or the R3 domain (For GA) of tau in vitro. However, the underlying molecular mechanisms of the inhibitive effects on the R3 domain of tau remain largely unknown. In this study, we conducted numerous all-atom molecular dynamics simulations on R3 dimers with and without EGCG, QE or GA, respectively. The results reveal that all three molecules can effectively decrease the ß structure composition of the R3 dimer, induce the dimer to adopt loosely-packed conformations, and weaken interchain interactions, thus impeding the dimerization of the R3 peptide chains. The specific preferentially binding sites for the three molecules exhibit similarities and differences. Hydrophobic, π-π stacking and hydrogen-bonding interactions collectively drive EGCG, QE and GA respectively binding on the R3 dimer, while QE also binds with the dimer through cation-π interaction. Given the incurable nature of tauopathies hitherto, our research provides helpful knowledge for the development of drugs to treat tauopathies.


Assuntos
Doença de Alzheimer , Tauopatias , Humanos , Proteínas tau/química , Quercetina/farmacologia , Ácido Gálico/farmacologia , Estudos Prospectivos , Doença de Alzheimer/metabolismo
19.
Complement Med Res ; 30(6): 535-543, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37952511

RESUMO

INTRODUCTION: Astragalus is used in traditional Chinese medicine for immune system disorders. Its effect on immune system function is evaluated in multiple studies. The objective of this systematic review and meta-analysis was to evaluate the effect of Astragalus on humoral and cellular immune response in human studies. METHODS: A comprehensive search of electronic databases was conducted to identify relevant studies published up to April 2023. Studies that assessed the impact of Astragalus on humoral and cellular immune markers were included. The data were extracted, and a random-effects meta-analysis was performed to determine the overall effect size. Subgroup analyses were conducted based on outcome measures. RESULTS: A total of 19 studies, including 1,094 human participants, were included in the meta-analysis. The analysis of humoral immune markers revealed a significant reduction in proinflammatory cytokines, including IL-2, IL-4, IL-6, IL-10, TNF-α, and IFN-γ, following Astragalus intervention (SMD -2.8765, 95% CI: -3.2385 to -2.5145, p < 0.0001). In the cellular immunity domain, Astragalus was found to significantly increase CD3 levels and the CD4/CD8 ratio (SMD 2.4629, 95% CI: 1.9598; 2.9661). Subgroup analyses based on outcome measures supported these findings. However, substantial heterogeneity was observed among the included studies. CONCLUSION: This systematic review and meta-analysis provide evidence supporting the immunomodulatory effects of Astragalus on humoral and cellular response. Astragalus demonstrated a significant reduction in proinflammatory cytokines and an enhancement of cellular immune markers, suggesting its potential as a therapeutic agent for immune-related disorders.EinleitungAstragalus wird in der traditionellen chinesischen Medizin bei Erkrankungen des Immunsystems eingesetzt. Seine Wirkung auf das Immunsystem ist in mehreren Studien untersucht worden. Das Ziel dieser systematischen Übersichtsarbeit und Metaanalyse ist es, die Wirkung von Astragalus auf die humorale und zelluläre Immunantwort in Studien am Menschen zu untersuchen.MethodenEine umfassende Suche in elektronischen Datenbanken wurde durchgeführt, um einschlägige Studien zu finden, die bis April 2023 veröffentlicht wurden. Eingeschlossen wurden Studien, die die Auswirkung von Astragalus auf Marker der humoralen und zellulären Immunantwort untersuchten. Die Daten wurden extrahiert und eine Random-Effects-Metaanalyse durchgeführt, um die Gesamt-Effektstärke zu ermitteln. Subgruppenanalysen wurden basierend auf Zielgrößen durchgeführt.ErgebnisseInsgesamt 19 Studien mit 1'094 menschlichen Teilnehmern wurden in die Metaanalyse eingeschlossen. Die Analyse der humoralen Immunmarker ergab eine signifikante Abnahme proinflammatorischer Zytokine, darunter IL-2, IL-4, IL-6, IL-10, TNF-α und IFN-γ, nach Anwendung von Astragalus (SMD ­2.8765; 95%-KI: −3.2385, −2.5145; p < 0.0001). Bei der zellulären Immunität zeigte Astralagus eine signifikante Erhöhung der CD3-Konzentration und des CD4/CD8-Quotienten (SMD 2.4629; 95%-KI: 1.9598, 2.9661). Die Subgruppenanalysen nach Zielgrößen bestätigten diese Ergebnisse. Zwischen den eingeschlossenen Studien bestand jedoch erhebliche Heterogenität.SchlussfolgerungDiese systematische Übersichtsarbeit und Metaanalyse liefert Belege für die immunmodulatorischen Effekte von Astragalus auf die humorale und zelluläre Immunantwort. Astragalus zeigte eine signifikante Abnahme proinflammatorischer Zytokine und eine Verbesserung von Markern der zellulären Immunität, was auf sein Potenzial als Therapeutikum bei immunvermittelten Störungen hindeutet.


Assuntos
Interleucina-10 , Interleucina-2 , Humanos , Interleucina-4 , Interleucina-6 , Fator de Necrose Tumoral alfa , Biomarcadores
20.
J Chem Inf Model ; 63(20): 6376-6385, 2023 10 23.
Artigo em Inglês | MEDLINE | ID: mdl-37782573

RESUMO

Medin is a principal component of localized amyloid found in the vasculature of individuals over 50 years old. Its amyloid aggregation has been linked to endothelial dysfunction and vascular inflammation, contributing to the pathogenesis of various vascular diseases. Despite its significance, the structures of the medin monomer, oligomer, and fibril remain elusive, and the dynamic processes of medin aggregation are not fully understood. In this study, we comprehensively investigated the medin folding and dimerization dynamics and conformations using atomistic discrete molecular dynamics simulations. Our simulation results suggested that the folding initiation of the medin involved the formation of ß-sheets around medin30-41 and medin42-50, with subsequent capping of other segments to their ß-sheet edges. Medin monomers typically consisted of three or four ß-strands, along with a dynamic N-terminal helix. Two isolated medin peptides readily aggregated into a ß-sheet-rich dimer, displaying a strong aggregation propensity. Dimerization of medin not only enhanced the ß-sheet conformations but also led to the formation of ß-barrel oligomers. The aggregation tendencies of medin1-18 and medin19-29 were relatively weak. However, the segments of medin30-41 and medin42-50 played a crucial role as they primarily formed a ß-sheet core and facilitated medin1-18 and medin19-29 to form intra- and interpeptide ß-sheets. The findings highlight the critical role of the medin30-41 and medin42-50 regions in stabilizing the monomer structure and driving the medin amyloid aggregation. These regions could potentially serve as promising targets for designing antiamyloid inhibitors against amyloid aggregation of medin. Additionally, our study provides a full picture of the monomer conformations and dimerization dynamics for medin, which will help better understand the pathology of medin aggregation.


Assuntos
Amiloide , Simulação de Dinâmica Molecular , Humanos , Pessoa de Meia-Idade , Dimerização , Amiloide/química , Peptídeos , Conformação Proteica em Folha beta , Peptídeos beta-Amiloides/química
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