Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 259
Filter
1.
Neural Regen Res ; 2024 Jul 29.
Article in English | MEDLINE | ID: mdl-39105365

ABSTRACT

A reduction in adult neurogenesis is associated with behavioral abnormalities in patients with Alzheimer's disease. Consequently, enhancing adult neurogenesis represents a promising therapeutic approach for mitigating disease symptoms and progression. Nonetheless, non-pharmacological interventions aimed at inducing adult neurogenesis are currently limited. Although individual non-pharmacological interventions, such as aerobic exercise, acousto-optic stimulation, and olfactory stimulation, have shown limited capacity to improve neurogenesis and cognitive function in patients with Alzheimer's disease, the therapeutic effect of a strategy that combines these interventions has not been fully explored. In this study, we observed an age-dependent decrease in adult neurogenesis and a concurrent increase in amyloid-beta accumulation in the hippocampus of amyloid precursor protein/presenilin 1 mice aged 2-8 months. Amyloid deposition became evident at 4 months, while neurogenesis declined by 6 months, further deteriorating as the disease progressed. However, following a 4-week multifactor stimulation protocol, which encompassed treadmill running (46 min/d, 10 m/min, 6 days per week), 40 Hz acousto-optic stimulation (1 hour/day, 6 days/week), and olfactory stimulation (1 hour/day, 6 days/week), we found a significant increase in the number of newborn cells (5'-bromo-2'-deoxyuridine-positive cells), immature neurons (doublecortin-positive cells), newborn immature neurons (5'-bromo-2'-deoxyuridine-positive/doublecortin-positive cells), and newborn astrocytes (5'-bromo-2'-deoxyuridine-positive/ glial fibrillary acidic protein-positive cells). Additionally, the amyloid-beta load in the hippocampus decreased. These findings suggest that multifactor stimulation can enhance adult hippocampal neurogenesis and mitigate amyloid-beta neuropathology in amyloid precursor protein/presenilin 1 mice. Furthermore, cognitive abilities were improved, and depressive symptoms were alleviated in amyloid precursor protein/presenilin 1 mice following multifactor stimulation, as evidenced by Morris water maze, novel object recognition, forced swimming test, and tail suspension test results. Notably, the efficacy of multifactor stimulation in consolidating immature neurons persisted for at least 2 weeks after treatment cessation. At the molecular level, multifactor stimulation upregulated the expression of neuron-related proteins (NeuN, doublecortin, postsynaptic density protein-95, and synaptophysin), anti-apoptosis-related proteins (Bcl-2 and PARP), and an autophagy-associated protein (LC3B), while decreasing the expression of apoptosis-related proteins (BAX and caspase-9), in the hippocampus of amyloid precursor protein/presenilin 1 mice. These observations might be attributable to both the brain-derived neurotrophic factor-mediated signaling pathway and antioxidant pathways. Furthermore, serum metabolomics analysis indicated that multifactor stimulation regulated differentially expressed metabolites associated with cell apoptosis, oxidative damage, and cognition. Collectively, these findings suggest that multifactor stimulation is a novel non-invasive approach for the prevention and treatment of Alzheimer's disease.

2.
Exp Hematol Oncol ; 13(1): 79, 2024 Aug 05.
Article in English | MEDLINE | ID: mdl-39103892

ABSTRACT

Previous studies have shown that the heterogeneity of tumor-associated fibroblasts (CAFs) in the tumor microenvironment may play a critical role in tumorigenesis; however, the biological function of CAFs in pancreatic cancer is still controversial. In this study, we found that CD105-positive (CD105+) CAF-derived exosomes significantly promoted the proliferative and invasive metastatic abilities of pancreatic cancer cells. Furthermore, RNA-seq and qRT‒PCR experiments revealed circAMPK1 as a key molecule in exosomes from CD105+ CAFs that mediates the malignant progression of pancreatic cancer. Furthermore, we demonstrated that circAMPK1 encodes a novel protein (AMPK1-360aa) in pancreatic cancer cells. This protein competes with AMPK1 to bind to the ubiquitination ligase NEDD4, which inhibits AMPK1 protein degradation and ubiquitination and thereby increases AMPK1 levels. Finally, we demonstrated that AMPK1-360aa induces cellular autophagy via NEDD4/AMPK1 to promote the proliferation and invasion of pancreatic cancer cells. In summary, circAMPK1 in CD105+ CAF-derived exosomes may mediate pancreatic cancer cell proliferation and invasive metastasis by inducing autophagy in target cells. Moreover, circAMPK1 may competitively bind to ubiquitinating enzymes through the encoded protein AMPK1-360aa, which in turn inhibits the ubiquitination-mediated degradation of AMPK1 and contributes to the upregulation of AMPK1 expression, thus inducing cellular autophagy to mediate the malignant progression of pancreatic cancer.

3.
Article in English | MEDLINE | ID: mdl-39134793

ABSTRACT

Landscape utilization is a green and environment-friendly way of disposing of compost sludge. Garden plants can extract heavy metals from the sludge of land use, but the effect is not enough to be widely used. Chelating agents have been found to facilitate the extraction of heavy metals from plants and are expected to be popularized if they are also environmentally friendly. In this study, the effects of methylglycinediacetic acid trisodium salt (MGDA), tetrasodium glutamate diacetate (GLDA), and ethylene diamine tetraacetate (EDTA) on the extraction of Ni and Cd from compost sludge by Symphytum officinale L. were studied through the pot experiment. Compared with the control group, the application of 5-10 mmol kg-1 MGDA and 1-9 mmol kg-1 GLDA promoted plant growth, while the application of 3-4 mmol kg-1 EDTA inhibited plant growth. The highest Ni content in shoots appeared in 4 mmol kg-1 GLDA treatment, which was 4.2 times that of the CK group. The highest shoot Cd concentration appeared in 4 mmol kg-1 EDTA treatment, 6.5 times that of CK. The promotion effects of the three reagents on the acid-extractable state of Cd were similar, while that of GLDA on the acid-extractable state of Ni was outstanding. The results of this study suggested that S. officinale could be a potential phytoextraction plant for Cd and Ni, and GLDA could friendly promote the Ni phytoextraction ability of the plant. The study provides a new and efficient method for phytoremediation of heavy metals in soil.

4.
J Am Chem Soc ; 2024 Aug 13.
Article in English | MEDLINE | ID: mdl-39136646

ABSTRACT

Macrocyclic peptides are promising scaffolds for the covalent ligand discovery. However, platforms enabling the direct identification of covalent macrocyclic ligands in a high-throughput manner are limited. In this study, we present an mRNA display platform allowing selection of covalent macrocyclic inhibitors using 1,3-dibromoacetone-vinyl sulfone (DBA-VS). Testcase selections on TEV protease resulted in potent covalent inhibitors with diverse cyclic structures, among which cTEV6-2, a macrocyclic peptide with a unique C-terminal cyclization, emerged as the most potent covalent inhibitor of TEV protease described to-date. This study outlines the workflow for integrating chemical functionalization─installation of a covalent warhead─with mRNA display and showcases its application in targeted covalent ligand discovery.

5.
Skin Res Technol ; 30(8): e13875, 2024 Aug.
Article in English | MEDLINE | ID: mdl-39120064

ABSTRACT

BACKGROUND: Recent studies increasingly suggest that microbial infections and the immune responses they elicit play significant roles in the pathogenesis of chronic inflammatory skin diseases. This study uses Mendelian randomization (MR) and Bayesian weighted Mendelian randomization (BWMR) to explore the causal relationships between immune antibody responses and four common skin diseases: psoriasis, atopic dermatitis (AD), rosacea, and vitiligo. METHODS: We utilized summary statistics from genome-wide association studies (GWAS) for antibody responses to 13 infectious pathogens and four skin diseases. Single nucleotide polymorphisms (SNPs) were selected as instrumental variables (IVs) to assess causal relationships using multiple MR methods, including inverse variance weighted (IVW), MR Egger, and weighted median. BWMR was also employed to confirm findings and address potential pleiotropy. RESULTS: The IVW analysis identified significant associations between specific antibody responses and the skin diseases studied. Key findings include protective associations of anti-Epstein-Barr virus (EBV) IgG seropositivity and Helicobacter pylori UREA antibody levels with psoriasis and AD. anti-chlamydia trachomatis IgG seropositivity, anti-polyomavirus 2 IgG seropositivity, and varicella zoster virus glycoprotein E and I antibody levels were negatively associated with rosacea, while EBV Elevated levels of the early antigen (EA-D) antibody levels and HHV-6 IE1B antibody levels were positively associated with rosacea. H. pylori Catalase antibody levels were protectively associated with vitiligo, whereas anti-herpes simplex virus 2 (HSV-2) IgG seropositivity was positively associated with vitiligo. The BWMR analysis confirmed these associations. CONCLUSION: This study underscores the significant role of H. pylori and other pathogens in these skin diseases, suggesting both protective and exacerbating effects depending on the specific condition. Understanding these pathogen-immune interactions can lead to the development of more effective, personalized treatments and preventative strategies, ultimately improving patient outcomes and quality of life.


Subject(s)
Bayes Theorem , Genome-Wide Association Study , Mendelian Randomization Analysis , Polymorphism, Single Nucleotide , Humans , Dermatitis, Atopic/immunology , Dermatitis, Atopic/genetics , Dermatitis, Atopic/microbiology , Dermatitis, Atopic/blood , Rosacea/immunology , Rosacea/genetics , Vitiligo/genetics , Vitiligo/immunology , Antibody Formation/genetics , Psoriasis/immunology , Psoriasis/genetics , Skin Diseases/immunology , Skin Diseases/genetics
6.
RSC Chem Biol ; 5(7): 691-702, 2024 Jul 03.
Article in English | MEDLINE | ID: mdl-38966676

ABSTRACT

Covalent protease inhibitors serve as valuable tools for modulating protease activity and are essential for investigating the functions of protease targets. These inhibitors typically consist of a recognition motif and a covalently reactive electrophile. Substrate peptides, featuring residues capable of fitting into the substrate pockets of proteases, undergo chemical modification at the carbonyl carbon of the P1 residue with an electrophile and have been widely applied in the development of covalent inhibitors. In this study, we utilized a DNA-encoded peptide library to replicate peptide binder sequences and introduced a vinyl sulfone warhead at the C-termini to construct the DNA-encoded peptide covalent inhibitor library (DEPCIL) for targeting cysteine proteases. Screening results toward 3CL protease demonstrated the efficacy of this library, not only in identifying protease inhibitors, but also in discovering amino acids that can conform to aligned protease pockets. The identified peptide sequences provide valuable insight into the amino acid preferences within substrate binding pockets, and our novel technology is indicative of the potential for similar strategies to discover covalent inhibitors and profile binding preferences of other proteases.

7.
Psychiatr Serv ; : appips20230176, 2024 Jul 19.
Article in English | MEDLINE | ID: mdl-39026468

ABSTRACT

OBJECTIVE: The authors compared the engagement, clinical outcomes, and adverse events of text or voice message-based psychotherapy (MBP) versus videoconferencing-based psychotherapy (VCP) among adults with depression. METHODS: The study used a sequential multiple-assignment randomized trial design with data drawn from phase 1 of a two-phase small business innovation research study. In total, 215 adults (ages ≥18 years) with depression received care from Talkspace, a digital mental health care company. Participants were initially randomly assigned to receive either asynchronous MBP or weekly VCP. All therapists provided evidence-based treatments such as cognitive-behavioral therapy. After 6 weeks of treatment, participants whose condition did not show a response on the Patient Health Questionnaire-9 or was rated as having not improved on the Clinical Global Impressions scale were randomly reassigned to receive either weekly VCP plus MBP or monthly VCP plus MBP. Longitudinal mixed-effects models with piecewise linear time trends applied to multiple imputed data sets were used to address missingness of data. RESULTS: Participants who were initially assigned to the MBP condition engaged with their therapists over more weeks than did participants in the VCP condition (7.8 weeks for MBP vs. 4.9 weeks for VCP; p<0.001). No meaningful differences were observed between the two groups in rates of change by 6 or 12 weeks for depression, anxiety, disability, or global ratings of improvement. Neither treatment resulted in any adverse events. CONCLUSIONS: MBP appears to be a viable alternative to VCP for treating adults with depression.

8.
Perioper Med (Lond) ; 13(1): 81, 2024 Jul 24.
Article in English | MEDLINE | ID: mdl-39049003

ABSTRACT

OBJECTIVE: Early diagnosis and prediction of organ dysfunction are critical for intervening and improving the outcomes of septic patients. The study aimed to find novel diagnostic and predictive biomarkers of organ dysfunction for perioperative septic patients. METHOD: This is a prospective, controlled, preliminary, and single-center study of emergency surgery patients. Mass spectrometry, Gene Ontology (GO) functional analysis, and the protein-protein interaction (PPI) network were performed to identify the differentially expressed proteins (DEPs) from sepsis patients, which were selected for further verification via enzyme-linked immunosorbent assay (ELISA). Logistic regression analysis was used to estimate the relative correlation of selected serum protein levels and clinical outcomes of septic patients. Calibration curves were plotted to assess the calibration of the models. RESULTS: Five randomized serum samples per group were analyzed via mass spectrometry, and 146 DEPs were identified. GO functional analysis and the PPI network were performed to evaluate the molecular mechanisms of the DEPs. Six DEPs were selected for further verification via ELISA. Cathepsin B (CatB), vascular cell adhesion protein 1 (VCAM-1), neutrophil gelatinase-associated lipocalin (NGAL), protein S100-A9, prosaposin, and thrombospondin-1 levels were significantly increased in the patients with sepsis compared with those of the controls (p < 0.001). Logistic regression analysis showed that CatB, S100-A9, VCAM-1, prosaposin, and NGAL could be used for preoperative diagnosis and postoperative prediction of organ dysfunction. CatB and S100-A9 were possible predictive factors for preoperative diagnosis of renal failure in septic patients. Internal validation was assessed using the bootstrapping validation. The preoperative diagnosis of renal failure model displayed good discrimination with a C-index of 0.898 (95% confidence interval 0.843-0.954) and good calibration. CONCLUSION: Serum CatB, S100-A9, VCAM-1, prosaposin, and NGAL may be novel markers for preoperative diagnosis and postoperative prediction of organ dysfunction. Specifically, S100-A9 and CatB were indicators of preoperative renal dysfunction in septic patients. Combining these two biomarkers may improve the accuracy of predicting preoperative septic renal dysfunction. TRIAL REGISTRATION: The study was registered at the Chinese Clinical Trials Registry (ChiCTR2200060418) on June 1, 2022.

10.
ACS Nano ; 18(32): 21221-21235, 2024 Aug 13.
Article in English | MEDLINE | ID: mdl-39079080

ABSTRACT

The mechanical properties of nanoparticles play a crucial role in regulating nanobiointeractions, influencing processes such as blood circulation, tumor accumulation/penetration, and internalization into cancer cells. Consequently, they have a significant impact on drug delivery and therapeutic efficacy. However, it remains unclear whether and how macrophages alter their biological function in response to nanoparticle elasticity. Here, we report on the nano-mechanical biological effects resulting from the interactions between elastic silica nanoparticles (SNs) and macrophages. The SNs with variational elasticity Young's moduli ranging from 81 to 837 MPa were synthesized, and it was demonstrated that M2 [tumor-associated macrophages (TAMs)] could be repolarized to M1 by the soft SNs. Additionally, our findings revealed that cell endocytosis, membrane tension, the curvature protein Baiap2, and the cytoskeleton were all influenced by the elasticity of SNs. Moreover, the mechanically sensitive protein Piezo1 on the cell membrane was activated, leading to calcium ion influx, activation of the NF-κB pathway, and the initiation of an inflammatory response. In vivo experiments demonstrated that the softest 81 MPa SNs enhanced tumor penetration and accumulation and repolarized TAMs in intratumoral hypoxic regions, ultimately resulting in a significant inhibition of tumor growth. Taken together, this study has established a cellular feedback mechanism in response to nanoparticle elasticity, which induces plasma membrane deformation and subsequent activation of mechanosensitive signals. This provides a distinctive "nano-mechanical immunoengineering" strategy for reprogramming TAMs to enhance cancer immunotherapy.


Subject(s)
Ion Channels , Nanoparticles , Tumor-Associated Macrophages , Animals , Nanoparticles/chemistry , Mice , Ion Channels/metabolism , Ion Channels/chemistry , Tumor-Associated Macrophages/metabolism , Tumor-Associated Macrophages/immunology , Silicon Dioxide/chemistry , Elasticity , RAW 264.7 Cells , Humans , Mice, Inbred BALB C
11.
Anal Chem ; 96(28): 11557-11565, 2024 07 16.
Article in English | MEDLINE | ID: mdl-38959297

ABSTRACT

Mitochondria (MT) and the endoplasmic reticulum (ER) maintain lipid and calcium homeostasis through membrane contacts, particularly MT-ER contacts (MERCs), spanning distances from 10 to 50 nm. However, the variation of different distance ranges and the metabolic factors influencing this variation remain poorly understood. This study employed microfluidic chip-based super-resolution microscopy in conjunction with a Moore-Neighbor tracing-incorporated organelle proximity analysis algorithm. This approach enabled precise three-dimensional localization of single-fluorescence protein molecules within narrow and irregular membrane proximities. It achieved lateral localization precision of less than 20 nm, resulting in a minimum MERC distance of approximately 8 nm in spatial and mean distances across multiple threshold ranges. Additionally, we demonstrated that the MERC distance variation was correlated with MT size rather than ER width. The proportion of each distance range varied significantly after the stimuli. Free cholesterol showed a negative correlation with various distances, while distances of 10-30 nm were associated with glucose, glutamine, and pyruvic acid. Furthermore, the 30-40 nm range was influenced by citric acid. These results underscore the role of advanced subcellular organelle analysis in elucidating the single-molecule behavior and organelle morphology in single-cell studies.


Subject(s)
Endoplasmic Reticulum , Mitochondria , Single-Cell Analysis , Endoplasmic Reticulum/metabolism , Mitochondria/metabolism , Mitochondria/chemistry , Humans , Microscopy, Fluorescence/methods , HeLa Cells
12.
BMC Med Res Methodol ; 24(1): 125, 2024 Jun 03.
Article in English | MEDLINE | ID: mdl-38831262

ABSTRACT

BACKGROUND: Mediation analysis is a powerful tool to identify factors mediating the causal pathway of exposure to health outcomes. Mediation analysis has been extended to study a large number of potential mediators in high-dimensional data settings. The presence of confounding in observational studies is inevitable. Hence, it's an essential part of high-dimensional mediation analysis (HDMA) to adjust for the potential confounders. Although the propensity score (PS) related method such as propensity score regression adjustment (PSR) and inverse probability weighting (IPW) has been proposed to tackle this problem, the characteristics with extreme propensity score distribution of the PS-based method would result in the biased estimation. METHODS: In this article, we integrated the overlapping weighting (OW) technique into HDMA workflow and proposed a concise and powerful high-dimensional mediation analysis procedure consisting of OW confounding adjustment, sure independence screening (SIS), de-biased Lasso penalization, and joint-significance testing underlying the mixture null distribution. We compared the proposed method with the existing method consisting of PS-based confounding adjustment, SIS, minimax concave penalty (MCP) variable selection, and classical joint-significance testing. RESULTS: Simulation studies demonstrate the proposed procedure has the best performance in mediator selection and estimation. The proposed procedure yielded the highest true positive rate, acceptable false discovery proportion level, and lower mean square error. In the empirical study based on the GSE117859 dataset in the Gene Expression Omnibus database using the proposed method, we found that smoking history may lead to the estimated natural killer (NK) cell level reduction through the mediation effect of some methylation markers, mainly including methylation sites cg13917614 in CNP gene and cg16893868 in LILRA2 gene. CONCLUSIONS: The proposed method has higher power, sufficient false discovery rate control, and precise mediation effect estimation. Meanwhile, it is feasible to be implemented with the presence of confounders. Hence, our method is worth considering in HDMA studies.


Subject(s)
Mediation Analysis , Propensity Score , Humans , Observational Studies as Topic/methods , Confounding Factors, Epidemiologic , Epigenomics/methods , Computer Simulation , Algorithms
13.
Front Nutr ; 11: 1418120, 2024.
Article in English | MEDLINE | ID: mdl-38887503

ABSTRACT

Composite natural emulsifiers such as whey protein isolate (WPI) and chitosan (CS) are commonly used in Pickering emulsions to address the effect of thermal deformation of proteins before complexation with CS and heating after complexation. In this study, the properties of WPI and CS composites were investigated by complexing CS with either unmodified WPI or thermally denatured WPI (DWPI). Three types of composite particles were prepared, WPI-CS, DWPI-CS, and D(WPI-CS). Atomic force microscopy revealed that the composite particles formed larger aggregates with increased contour size and surface roughness compared to CS and WPI, whereas the interfacial tension decreased, indicating improved emulsifying abilities. Fourier-transform infrared analysis revealed differences in the hydrogen bonds between CS and WPI/DWPI. All three composite particles formed stable emulsions with droplet sizes of 20.00 ± 0.15, 27.80 ± 0.35, and 16.77 ± 0.51 µm, respectively. Thermal stability experiments revealed that the curcumin emulsion stabilized with WPI-CS and DWPI-CS exhibited relatively better thermal stability than that stabilized with D(WPI-CS). In vitro experiments results indicated that the bioaccessibility of the curcumin emulsion stabilized with WPI-CS was 61.18 ± 0.16%, significantly higher than that of the emulsions prepared with the other two composite particles (p < 0.05). This study will enable the customized design of WPI composite-based Pickering emulsions for application in the food and nutrition industries.

15.
Pharm Res ; 41(6): 1257-1270, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38844745

ABSTRACT

PURPOSE: Cinchoninze hydrochloride solves the problem of the low solubility of cinchonine, but it is unstable and susceptible to deliquescence. In this study, we designed and prepared cinchonine cocrystal salts or cinchonine salts with better stability, solubility and antioxidant activity than cinchonine. METHOD: We successfully synthesized and characterized three cinchonine salts, namely, cinchonine-fumaric acid, cinchonine-isoferulic acid, and cinchonine-malic acid. The high humidity (92.5% RH) and high temperature (60°C) tests were conducted to determine the physical stability and hygroscopicity of cinchonine hydrochloride, cinchonine and three cinchonine salts. And the ultraviolet spectrophotometry was conducted to determine the equilibrium solubility and intrinsic dissolution rate of cinchonine and salts. Moreover, the DPPH, ABTS, and FRAP assays determined the antioxidant activity of cinchonine and salts. RESULT: Compared with cinchonine hydrochloride and cinchonine, all three cinchonine salts exhibited good physical stability over 15 days under high humidity (92.5% RH) and high temperature (60°C) conditions. While cinchonine and cinchonine hydrochloride are categorized as hygroscopic and deliquescent, respectively, three cinchonine salts are classified as slightly hygroscopic, meaning that they have a lower hygroscopicity than cinchonine and cinchonine hydrochloride. And three cinchonine salts had higher equilibrium solubility, faster intrinsic dissolution rates, and higher antioxidant activity in comparison to cinchonine. Moreover, they showed a "spring and parachute" pattern in the phosphate buffer (pH = 6.8). CONCLUSION: Cocrystallization technology is a viable option for improving cinchonine's poor physicochemical qualities.


Subject(s)
Antioxidants , Crystallization , Drug Stability , Solubility , Antioxidants/chemistry , Antioxidants/pharmacology , Wettability , Chemistry, Pharmaceutical/methods , Humidity , Salts/chemistry
16.
iScience ; 27(6): 110051, 2024 Jun 21.
Article in English | MEDLINE | ID: mdl-38904067

ABSTRACT

Scent marking sites served as a primary means of chemical communication for giant pandas, enabling intraspecific communication. We integrated metabolomics and high-throughput sequencing techniques to examine the non-targeted metabolome and microbial community structure of scent marking sites and feces in the field. Integrative analysis revealed a more comprehensive array of chemical compounds compared to previous investigations, including ketones, acids, heterocycles, alcohols, and aldehydes. Notably, specific compounds such as 2-decenal, (E)-, octanal, decanal, L-α-terpineol, vanillin, and nonanal emerged as potential key players in scent signaling. Intriguingly, our study of the microbial domain identified dominant bacterial species from the Actinobacteria, Bacteroidetes, and Proteobacteria phyla, likely orchestrating metabolic processes at scent marking sites. Comparative analyses showed, for the first time, that feces do not share the same functions as scent markers, indicating distinct functional roles. This research deepens scientific understanding of chemical communication in wild pandas.

17.
ACS Sens ; 9(7): 3720-3729, 2024 Jul 26.
Article in English | MEDLINE | ID: mdl-38941307

ABSTRACT

Fluorescence-based contrast agents enable real-time detection of solid tumors and their neovasculature, making them ideal for use in image-guided surgery. Several agents have entered late-stage clinical trials or secured FDA approval, suggesting they are likely to become the standard of care in cancer surgeries. One of the key parameters to optimize in contrast agents is molecular size, which dictates much of the pharmacokinetic and pharmacodynamic properties of the agent. Here, we describe the development of a class of protease-activated quenched fluorescent probes in which a N-(2-hydroxypropyl)methacrylamide copolymer is used as the primary scaffold. This copolymer core provides a high degree of probe modularity to generate structures that cannot be achieved with small molecules and peptide probes. We used a previously validated cathepsin substrate and evaluated the effects of length and type of linker, as well as the positioning of the fluorophore/quencher pair on the polymer core. We found that the polymeric probes could be optimized to achieve increased overall signal and tumor-to-background ratios compared to the reference small molecule probe. Our results also revealed multiple structure-activity relationship trends that can be used to design and optimize future optical imaging probes. Furthermore, they confirm that a hydrophilic polymer is an ideal scaffold for use in optical imaging contrast probes, allowing a highly modular design that enables efficient optimization to maximize probe accumulation and overall biodistribution properties.


Subject(s)
Fluorescent Dyes , Neoplasms , Fluorescent Dyes/chemistry , Fluorescent Dyes/chemical synthesis , Animals , Neoplasms/diagnostic imaging , Humans , Mice , Optical Imaging/methods , Peptide Hydrolases/metabolism , Polymers/chemistry , Cell Line, Tumor , Acrylamides/chemistry
18.
Discov Oncol ; 15(1): 138, 2024 May 01.
Article in English | MEDLINE | ID: mdl-38691224

ABSTRACT

Breast cancer (BC) ranks first among female malignant tumors and involves hormonal changes and genetic as well as environmental risk factors. In recent years, with the improvement of medical treatment, a variety of therapeutic approaches for breast cancer have emerged and have strengthened to accommodate molecular diversity. However, the primary way to improve the effective treatment of breast cancer patients is to overcome treatment resistance. Recent studies have provided insights into the mechanisms of resistance to exosome effects in BC. Exosomes are membrane-bound vesicles secreted by both healthy and malignant cells that facilitate intercellular communication. Specifically, exosomes released by tumor cells transport their contents to recipient cells, altering their properties and promoting oncogenic components, ultimately resulting in drug resistance. As important coordinators, non-coding RNAs (ncRNAs) are involved in this process and are aberrantly expressed in various human cancers. Exosome-derived ncRNAs, including microRNAs (miRNAs), long-noncoding RNAs (lncRNAs), and circular RNAs (circRNAs), have emerged as crucial components in understanding drug resistance in breast cancer. This review provides insights into the mechanism of exosome-derived ncRNAs in breast cancer drug resistance, thereby suggesting new strategies for the treatment of BC.

19.
bioRxiv ; 2024 May 09.
Article in English | MEDLINE | ID: mdl-38766164

ABSTRACT

Fluorescence-based contrast agents enable real-time detection of solid tumors and their neovasculature, making them ideal for use in image-guided surgery. Several agents have entered late-stage clinical trials or secured FDA approval, suggesting they are likely to become standard of care in cancer surgeries. One of the key parameters to optimize in contrast agent is molecular size, which dictates much of the pharmacokinetic and pharmacodynamic properties of the agent. Here, we describe the development of a class of protease-activated quenched fluorescent probes in which a N-(2-hydroxypropyl)methacrylamide copolymer is used as the primary scaffold. This copolymer core provides a high degree of probe modularity to generate structures that cannot be achieved with small molecules and peptide probes. We used a previously validated cathepsin substrate and evaluated the effects of length and type of linker as well as positioning of the fluorophore/quencher pair on the polymer core. We found that the polymeric probes could be optimized to achieve increased over-all signal and tumor-to-background ratios compared to the reference small molecule probe. Our results also revealed multiple structure-activity relationship trends that can be used to design and optimize future optical imaging probes. Furthermore, they confirm that a hydrophilic polymer is an ideal scaffold for use in optical imaging contrast probes, allowing a highly modular design that enables efficient optimization to maximize probe accumulation and overall biodistribution properties.

20.
Chem Commun (Camb) ; 60(37): 4898-4901, 2024 May 02.
Article in English | MEDLINE | ID: mdl-38629248

ABSTRACT

A heart-on-a-particle model based on multicompartmental microgel is proposed to simulate the heart microenvironment and study the cardiotoxicity of drugs. The relevant microgel was fabricated by a biocompatible microfluidic-based approach, where heart function-related HL-1 and HUVEC cells were arranged in separate compartments. Finally, the mechanism of aconitine-induced heart toxicity was elucidated using mass spectrometry and molecular biotechnology.


Subject(s)
Aconitine , Human Umbilical Vein Endothelial Cells , Lab-On-A-Chip Devices , Aconitine/chemistry , Humans , Cardiotoxicity/etiology , Cell Line , Particle Size , Cell Survival/drug effects
SELECTION OF CITATIONS
SEARCH DETAIL