Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 882
Filter
1.
Front Oncol ; 14: 1435029, 2024.
Article in English | MEDLINE | ID: mdl-39104720

ABSTRACT

Homologous recombination (HR) is a highly conserved DNA repair system, in which aberrations can lead to the accumulation of DNA damage and genomic scars known as homologous recombination deficiency (HRD). The identification of mutations in key genes (i.e., BRCA1, and BRCA2 (BRCA)) and the quantification of large-scale structural variants (e.g., loss of heterozygosity) are indicators of the HRD phenotype. HRD is a stable biomarker and remains unchanged during recurrence, but fails to reveal the molecular profile of tumor progression. Moreover, interpretation of the current HRD score lacks comprehensiveness, especially for the HR-proficient group. Poly (ADP-ribose) polymerase (PARP) enzymes play an important role in the repair of DNA single-strand breaks, the blockage of which using PARP inhibitors (PARPi) can generate synthetic lethality in cancer cells with HRD. Although numerous studies have demonstrated that the benefit of PARPi is substantial in ovarian cancer (OC) patients, the efficacy is limited by the development of resistance, and seems to be irrespective of HR and/or BRCA mutation status. Moreover, in addition to improving progression-free survival, long-term benefit as overall survival brought by PARPi for advanced, recurrent and refractory OC patients remains unclear. Therefore, further investigations are needed to uncover the role of HR genes beyond BRCA and their interactions with other oncogenic pathways, to determine the value of HRD in the recurrent setting, and to identify alternative strategies for the precise management of advanced, refractory OC patients.

2.
Front Pharmacol ; 15: 1426803, 2024.
Article in English | MEDLINE | ID: mdl-39156108

ABSTRACT

Introduction: Inflammatory bowel disease (IBD) is a globally emergent chronic inflammatory disease which commonly requires lifelong care. To date, there remains a pressing need for the discovery of novel anti-inflammatory therapeutic agents against this disease. Sheng Mai San (SMS) is a traditional Chinese medicine prescription with a long history of use for treating Qi and Yin deficiency and recent studies have shown that SMS exhibits anti-inflammatory potential. However, the effects of SMS on the gastrointestinal system remain poorly studied, and its therapeutic potential and underlying molecular mechanisms in IBD have yet to be discovered. In this study, we examined the therapeutic efficacy of SMS in IBD and its anti-inflammatory activity and underlying molecular mechanism, in vivo and in vitro. Methods: The therapeutic efficacy of SMS in IBD was assessed in the DSS-induced acute colitis mouse model. Body weight, stool consistency, rectal bleeding, colon length, organ coefficient, cytokine levels in colon tissues, infiltration of immune cells, and colon pathology were evaluated. The anti-inflammatory activity of SMS and related molecular mechanisms were further examined in lipopolysaccharide (LPS)-induced macrophages via assessment of pro-inflammatory cytokine secretion and NF-κB, MAPK, STAT3, and NLRP3 signalling. Results: SMS significantly ameliorated the severity of disease in acute colitis mice, as evidenced by an improvement in disease activity index, colon morphology, and histological damage. Additionally, SMS reduced pro-inflammatory cytokine production and infiltration of immune cells in colon tissues. Furthermore, in LPS-induced macrophages, we demonstrated that SMS significantly inhibited the production of cytokines and suppressed the activation of multiple pro-inflammatory signalling pathways, including NF-κB, MAPK, and STAT3. SMS also abolished NLRP3 inflammasome activation and inhibited subsequent caspase-1 activation and IL-1ß secretion, suggesting a new therapeutic target for the treatment of IBD. These mechanistic findings were also confirmed in in vivo assays. Conclusion: This study presents the anti-inflammatory activity and detailed molecular mechanism of SMS, in vitro and in vivo. Importantly, we highlight for the first time the potential of SMS as an effective therapeutic agent against IBD.

3.
Adv Sci (Weinh) ; : e2407596, 2024 Aug 14.
Article in English | MEDLINE | ID: mdl-39140246

ABSTRACT

Inspired by the Mimosa plant, this study herein develops a unique dynamic shape memory polymer (SMP) network capable of transitioning from hard to pliable with heat, featuring reversible actuation, self-healing, recyclability, and degradability. This material is adept at simulating the functionalities of artificial muscles for a variety of tasks, with a remarkable specific energy density of 1.8 J g-1-≈46 times higher than that of human skeletal muscle. As an intelligent manipulator, it demonstrates remarkable proficiency in identifying and handling items at high temperatures. Its suitable rate of shape recovery around human body temperature indicates its promising utility as an implant material for addressing acute obstructions. The dynamic covalent bonding within the network structure not only provides excellent resistance to solvents but also bestows remarkable abilities for self-healing, reprocessing, and degradation. These attributes significantly boost its practicality and environmental sustainability. Anticipated to promote advancements in the sectors of biomedical devices, soft robotics, and smart actuators, this SMP network represents a forward leap in simulating artificial muscles, marking a stride toward the future of adaptive and sustainable technology.

4.
J Colloid Interface Sci ; 677(Pt A): 739-749, 2024 Aug 05.
Article in English | MEDLINE | ID: mdl-39121658

ABSTRACT

HYPOTHESIS: Hydrogel actuators powered by chemical fuels are pivotal in autonomous soft robotics. Nevertheless, chemical waste accumulation caused by chemical fuels hampers the development of programmable and reusable hydrogel actuating systems. We propose the concept of ionic fuel-powered soft robotics which are constructed by programmable salt-responsive actuators and use waste-free ionic fuels. EXPERIMENTS: Herein, soft hydrogel actuators were developed by orchestrating the Janus bilayer hydrogels' capacity for swelling and shrinking. Decomposable and easily removable ionic fuels were applied to power the actuators. Swelling tests were used to evaluate the deformability of the hydrogels. Tensile tests were performed to investigate the modulus of the hydrogels. The bonded interface composed of the interpenetrating polymer chains from both hydrogel layers bilayer was evidenced by the optical microscopy and scanning electron microscopy. The ionic conductivities of solutions were determined by a conductivity meter. Furthermore, a range of biomimetic soft robots with various shapes and asymmetrical structures have been designed and fabricated to execute complex functions. FINDINGS: The programmable actuators powered by ionic fuel exhibit adjustable bending orientations, amplitudes, and durations, along with consistent cyclic actuations enabled by replenishment of the fuel without noticeable loss in performance. Many life-like programmable soft robotic systems were designed, indicating spatiotemporally controllable functions.

5.
Drug Des Devel Ther ; 18: 3461-3476, 2024.
Article in English | MEDLINE | ID: mdl-39132626

ABSTRACT

Cardiovascular diseases (CVDs) tend to affect the young population and are associated with a significant economic burden and psychological distress to the society and families. The physiological and pathological processes underlying CVDs are complex. Ca2+/calmodulin-dependent kinase II (CaMK II), a protein kinase, has multiple biological functions. It participates in multiple pathological processes and plays a central role in the development of CVDs. Based on this, this paper analyzes the structural characteristics and distribution of CaMK II, the mechanism of action of CaMK II, and the relationship between CaMK II and CVDs, including ion channels, ischemia-reperfusion injury, arrhythmias, myocardial hypertrophy, cardiotoxicity, hypertension, and dilated cardiomyopathy. Given the different regulatory mechanisms of different isoforms of CaMK II, the clinical use of specific targeted inhibitors or novel compounds should be evaluated in future research to provide new directions.


Subject(s)
Calcium-Calmodulin-Dependent Protein Kinase Type 2 , Cardiovascular Diseases , Humans , Calcium-Calmodulin-Dependent Protein Kinase Type 2/metabolism , Calcium-Calmodulin-Dependent Protein Kinase Type 2/antagonists & inhibitors , Animals , Protein Kinase Inhibitors/pharmacology , Protein Kinase Inhibitors/chemistry
6.
Mol Ther Nucleic Acids ; 35(3): 102283, 2024 Sep 10.
Article in English | MEDLINE | ID: mdl-39165562

ABSTRACT

The implementation of targeted molecular therapies and immunotherapy in melanoma vastly improved the therapeutic outcome in patients with limited efficacy of surgical intervention. Nevertheless, a large fraction of patients with melanoma still remain refractory or acquire resistance to these new forms of treatment, illustrating a need for improvement. Here, we report that the clinically relevant combination of mitogen-activated protein (MAP) kinase pathway inhibitors dabrafenib and trametinib synergize with RIG-I agonist-induced immunotherapy to kill BRAF-mutated human and mouse melanoma cells. Kinase inhibition did not compromise the agonist-induced innate immune response of the RIG-I pathway in host immune cells. In a melanoma transplantation mouse model, the triple therapy outperformed individual therapies. Our study suggests that agonist-induced activation of RIG-I with its synthetic ligand 3pRNA could vastly improve tumor control in a substantial fraction of patients with melanoma receiving MAP kinase inhibitors.

7.
J Ethnopharmacol ; 335: 118645, 2024 Jul 31.
Article in English | MEDLINE | ID: mdl-39089661

ABSTRACT

ETHNOPHARMACOLOGICAL RELEVANCE: Ulcerative colitis (UC) is a chronic inflammatory bowel condition that is frequently related with Spleen-Kidney Yang Deficiency Syndrome (SKYD) in Chinese medicine. Fuzi Lizhong Pill (FLZP), a traditional medicine for SKYD, has been utilized in China for generations, although the exact mechanism by which it treats UC is unknown. AIM OF THE STUDY: The goal of this study is to further understand FLZP's therapeutic mechanism in SKYD-associated UC. MATERIALS AND METHODS: To investigate the impact of FLZP on SKYD-associated UC, we used a comprehensive method that included serum metabolomics and gut microbiota profiling. The chemical composition of FLZP was determined using mass spectrometry. UC rats with SKYD were induced and treated with FLZP. Serum metabolomics and 16S rRNA microbial community analysis were used to evaluate FLZP's effects on endogenous metabolites and gut microbiota, respectively. Correlation analysis investigated the association between metabolites and intestinal flora. A metabolic pathway analysis was undertaken to discover putative FLZP action mechanisms. RESULTS: FLZP contains 109 components, including liquiritin (584.8176 µg/g), benzoylaconine (16.3087 µg/g), benzoylhypaconine (31.9583), and hypaconitine (8.1160 µg/g). FLZP predominantly regulated seven metabolites and eight metabolic pathways involved in amino acid and nucleotide metabolism, with an emphasis on energy metabolism and gastrointestinal digestion. FLZP also influenced intestinal flora variety, increasing probiotic abundance while decreasing pathogenic bacteria prevalence. An integrated investigation identified associations between changes in certain gut flora and energy metabolism, specifically the tricarboxylic acid (TCA) cycle. CONCLUSIONS: FLZP successfully cures UC in SKYD rats by regulating amino acid and energy metabolism. Its positive effects may include altering microbiota composition and metabolite profiles in UC rats with SKYD. These findings shed light on FLZP's mode of action and its implications for UC management.

9.
Front Oncol ; 14: 1386597, 2024.
Article in English | MEDLINE | ID: mdl-38947889

ABSTRACT

Treatment intensification with androgen deprivation therapy (ADT) and androgen receptor pathway inhibitors (ARPi) have led to improved survival in advanced prostate cancer. However, ADT is linked to significant cardiovascular toxicity, and ARPi also negatively impacts cardiovascular health. Together with a higher prevalence of baseline cardiovascular risk factors reported among prostate cancer survivors at diagnosis, there is a pressing need to prioritise and optimise cardiovascular health in this population. Firstly, While no dedicated cardiovascular toxicity risk calculators are available, other tools such as SCORE2 can be used for baseline cardiovascular risk assessment. Next, selected patients on combination therapy may benefit from de-escalation of ADT to minimise its toxicities while maintaining cancer control. These patients can be characterised by an exceptional PSA response to hormonal treatment, favourable disease characteristics and competing comorbidities that warrant a less aggressive treatment regime. In addition, emerging molecular and genomic biomarkers hold the potential to identify patients who are suited for a de-escalated treatment approach either with ADT or with ARPi. One such biomarker is AR-V7 splice variant that predicts resistance to ARPi. Lastly, optimization of modifiable cardiovascular risk factors for patients through a coherent framework (ABCDE) and exercise therapy is equally important. This article aims to comprehensively review the cardiovascular impact of hormonal manipulation in metastatic hormone-sensitive prostate cancer, propose overarching strategies to mitigate cardiovascular toxicity associated with hormonal treatment, and, most importantly, raise awareness about the detrimental cardiovascular effects inherent in our current management strategies involving hormonal agents.

10.
Zhongguo Zhong Yao Za Zhi ; 49(13): 3574-3582, 2024 Jul.
Article in Chinese | MEDLINE | ID: mdl-39041129

ABSTRACT

This study aimed to investigate the therapeutic effect of Shenfu Injection on mice with chronic heart failure(CHF) and its effect on macrophage polarization. C57BL/6J mice were randomly assigned to the normal and model groups. The CHF model was established by intraperitoneal injection of isoproterenol(ISO, 7.5 mg·kg~(-1), 28 d). The successful modeling was determined by asses-sing the cardiac function and N-terminal pro-brain natriuretic peptide(NT-proBNP). The modeled mice were randomly divided into the model group, Shenfu Injection group, and TAK-242 group, and were injected intraperitoneally with the corresponding drugs for 15 days. Cardiac function was evaluated using echocardiography. Hematoxylin-eosin(HE) staining was used to detect the pathomorphology. Enzyme-linked immunosorbent assay(ELISA) was used to detect the values of serum NT-proBNP, interleukin-6(IL-6), tumor necrosis factor-α(TNF-α), IL-10, and arginase 1(Arg-1). Flow cytometry was applied to detect the relative content and M1/M2 polarization of cardiac macrophages. Quantitative polymerase chain reaction(qPCR) and Western blot were used to detect the changes in the Toll-like receptor 4(TLR4)/nuclear factor-κB(NF-κB) pathway-related mRNA and protein expressions. Compared with the normal group, mice in the model group had lower values of left ventricular ejection fraction(LVEF) and left ventricular fractional shorte-ning(LVFS), higher values of left ventricular internal diastolic end-diastolic(LVIDd), left ventricular internal diastolic end-systolic(LVIDs), NT-proBNP, TNF-α, and IL-6(P<0.01); the number of macrophages increased in cardiac tissues(P<0.05), and the values of M1-F4/80~+CD86~+ were increased(P<0.01), while the values of M2-F4/80~+CD163~+ decreased(P<0.05); the mRNA and protein expressions of TLR4, myeloid differentiation factor 88(MyD88), IκB kinase α(IKKα), and NF-κB p65 in myocardial tissues were significantly elevated(P<0.05, P<0.01). Compared with the model group, mice in the Shenfu Injection and TAK-242 groups showed elevated LVEF, LVFS, IL-10, and Arg-1 levels, and decreased LVIDd, LVIDs, NT-proBNP, TNF-α, and IL-6 levels(P<0.05, P<0.01); the cardiac F4/80~+CD11b~+(macrophage) and M1-F4/80~+ CD86~+ values were significantly down-regulated, while M2-F4/80~+CD163~+ values were increased(P<0.05, P<0.01); and the mRNA and protein expressions of TLR4, MyD88, IKKα, and NF-κB p65 in myocardial tissues were notably decreased(P<0.05, P<0.01). CHF mice have an imbalance of M1/M2 macrophage polarization, with M1-type macrophages predominating. Shenfu Injection promotes macrophage polarization towards M2, inhibits M1-type macrophage activation, and attenuates inflammatory responses in heart failure by regulating the TLR4/NF-κB signaling pathway.


Subject(s)
Drugs, Chinese Herbal , Heart Failure , Macrophages , Mice, Inbred C57BL , NF-kappa B , Toll-Like Receptor 4 , Animals , Toll-Like Receptor 4/metabolism , Toll-Like Receptor 4/genetics , Drugs, Chinese Herbal/administration & dosage , Drugs, Chinese Herbal/pharmacology , Heart Failure/drug therapy , Heart Failure/physiopathology , Heart Failure/metabolism , NF-kappa B/genetics , NF-kappa B/metabolism , Mice , Macrophages/drug effects , Macrophages/metabolism , Male , Signal Transduction/drug effects , Inflammation/drug therapy , Humans , Chronic Disease , Tumor Necrosis Factor-alpha/genetics , Tumor Necrosis Factor-alpha/metabolism
11.
ALTEX ; 41(3): 402-424, 2024.
Article in English | MEDLINE | ID: mdl-38898799

ABSTRACT

The webinar series and workshop titled "Trust Your Gut: Establishing Confidence in Gastrointestinal Models ­ An Overview of the State of the Science and Contexts of Use" was co-organized by NICEATM, NIEHS, FDA, EPA, CPSC, DoD, and the Johns Hopkins Center for Alternatives to Animal Testing (CAAT) and hosted at the National Institutes of Health in Bethesda, MD, USA on October 11-12, 2023. New approach methods (NAMs) for assessing issues of gastrointestinal tract (GIT)- related toxicity offer promise in addressing some of the limitations associated with animal-based assessments. GIT NAMs vary in complexity, from two-dimensional monolayer cell line-based systems to sophisticated 3-dimensional organoid systems derived from human primary cells. Despite advances in GIT NAMs, challenges remain in fully replicating the complex interactions and pro­cesses occurring within the human GIT. Presentations and discussions addressed regulatory needs, challenges, and innovations in incorporating NAMs into risk assessment frameworks; explored the state of the science in using NAMs for evaluating systemic toxicity, understanding absorption and pharmacokinetics, evaluating GIT toxicity, and assessing potential allergenicity; and discussed strengths, limitations, and data gaps of GIT NAMs as well as steps needed to establish confidence in these models for use in the regulatory setting.


Non-animal methods to assess whether chemicals may be toxic to the human digestive tract promise to complement or improve on animal-based methods. These approaches, which are based on human or animal cells and/or computer models, are faced with their own technical challenges and need to be shown to predict adverse effects in humans. Regulators are tasked with evaluating submitted data to best protect human health and the environment. A webinar series and workshop brought together scientists from academia, industry, military, and regulatory authorities from dif­ferent countries to discuss how non-animal methods can be integrated into the risk assessment of drugs, food additives, dietary supplements, pesticides, and industrial chemicals for gastrointestinal toxicity.


Subject(s)
Animal Testing Alternatives , Gastrointestinal Tract , Humans , Animal Testing Alternatives/methods , Animals , Models, Biological , Risk Assessment/methods , Toxicity Tests/methods
12.
J Antibiot (Tokyo) ; 2024 Jun 26.
Article in English | MEDLINE | ID: mdl-38926492

ABSTRACT

Two new depside antibiotics, geministatins A (1) and B (2), were isolated from the fungus Austroacremonium gemini MST-FP2131 (Sordariomycetes, Ascomycota), which was recovered from rotting wood in the wet tropics of northern Australia. The structures of the geministatins were elucidated by detailed spectroscopic analysis, chemical degradation and comparison with literature values. Chemical degradation of 1 and 2 yielded three new analogues, geministatins C-E (3-5), as well as a previously reported compound dehydromerulinic acid A (6). Compounds 1, 2 and 6 exhibited antibacterial activity against the Gram-positive bacteria Bacillus subtilis (MIC 0.2-1.6 µg mL-1) and Staphylococcus aureus (MIC 0.78-6.3 µg mL-1), including methicillin-resistant S. aureus (MRSA), while 4 exhibited antifungal activity against the yeast Saccharomyces cerevisiae (MIC 13 µg mL-1).

13.
Anal Methods ; 16(24): 3831-3838, 2024 Jun 20.
Article in English | MEDLINE | ID: mdl-38828794

ABSTRACT

We designed and prepared probe W-1 for the detection of H2O2. W-1 showed excellent selectivity for H2O2 and was accompanied by colorimetric signal changes. The excellent linear relationship between fluorescence intensity and H2O2 concentration (0-100 µM) provided favorable conditions for its quantitative detection. In addition, the combination of portable test strips with a smartphone platform provided great convenience for on-site visual detection of H2O2. Moreover, W-1 possessed targeting mitochondria property and could be applied to image the exogenous and endogenous H2O2 in cells to distinguish normal cells and cancer cells. Lastly, W-1 was used for monitoring the H2O2 fluctuation of the diabetic process in mice, and the results showed an increase in H2O2 levels in diabetes. Therefore, the probe provided a tool for understanding the pathological and physiological mechanisms of diabetes by imaging H2O2.


Subject(s)
Diabetes Mellitus, Experimental , Fluorescent Dyes , Hydrogen Peroxide , Mitochondria , Hydrogen Peroxide/metabolism , Animals , Mitochondria/metabolism , Fluorescent Dyes/chemistry , Mice , Humans , Colorimetry/methods , Optical Imaging/methods
14.
Biomedicines ; 12(6)2024 Jun 20.
Article in English | MEDLINE | ID: mdl-38927577

ABSTRACT

Multipotent mesenchymal stromal cells (MSCs) hold promises for cell therapy and tissue engineering due to their self-renewal and differentiation abilities, along with immunomodulatory properties and trophic factor secretion. Extracellular vesicles (EVs) from MSCs offer similar therapeutic effects. However, MSCs are heterogeneous and lead to variable outcomes. In vitro priming enhances MSC performance, improving immunomodulation, angiogenesis, proliferation, and tissue regeneration. Various stimuli, such as cytokines, growth factors, and oxygen tension, can prime MSCs. Two classical priming methods, interferon-gamma (IFN-γ) and hypoxia, enhance MSC immunomodulation, although standardized protocols are lacking. This review discusses priming protocols, highlighting the most commonly used concentrations and durations, along with mechanisms and in vivo therapeutics effects of primed MSCs and their EVs. The feasibility of up-scaling their production was also discussed. The review concluded that priming with IFN-γ or hypoxia (alone or in combination with other factors) boosted the immunomodulation capability of MSCs and their EVs, primarily via the JAK/STAT and PI3K/AKT and Leptin/JAK/STAT and TGF-ß/Smad signalling pathways, respectively. Incorporating priming in MSC and EV production enables translation into cell-based or cell-free therapies for various disorders.

15.
Waste Manag ; 186: 55-63, 2024 Sep 15.
Article in English | MEDLINE | ID: mdl-38861772

ABSTRACT

Metal smelting and combustion of solid fuels produce significant quantities of waste slag, leading to issues such as land occupation and environmental pollution. Understanding and controlling the microscale crystallization phenomena of these slags during thermal treatment is crucial for transforming waste slags into materials suitable for carbon capture or glass ceramics. Previous research has primarily focused on macroscopic crystallization behaviors, significantly advancing the utilization of waste slags in cement clinker production. However, macroscopic results are inadequate for precisely controlling the microscale crystallization behaviors of waste slags. Here, we employed the single hot thermocouple technique to visually explore crystal growth modes, shapes, sizes, numbers, and translational rates of the crystal growth front in a representative blast furnace slag under various isothermal temperatures. The results revealed that crystals exhibited five modes as the isothermal temperature gradually increased, including equiaxed, equiaxed & columnar, columnar, columnar & planar, and planar. Moreover, the translational rate of the crystal growth front increased from 0.011 µm·s-1 to 43.7 µm·s-1 with an increase in the isothermal temperature. Simultaneously, the number of crystals decreased from around 104 to 100 µm-2. On this basis, correlations between microscale crystallization behaviors and isothermal temperature were established to fill the current gap.


Subject(s)
Crystallization , Waste Management/methods , Industrial Waste/analysis
16.
Anal Chim Acta ; 1315: 342817, 2024 Aug 01.
Article in English | MEDLINE | ID: mdl-38879215

ABSTRACT

Diabetes has become one of the most common endocrine and metabolic diseases threatening human health, which can induce mitochondrial dysfunction and exacerbate the excessive production of reactive oxygen species (ROS). Among them, ONOO- level fluctuation was closely related to diabetes. Hence, it is of great significance to develop a near-infrared fluorescence probe for visualizing ONOO- level fluctuations in diabetes. In this paper, we constructed a fluorescence probe YBL with dicyano-isophorone derivative as fluorophore and diphenyl phosphate as ONOO- response site, which can detect ONOO- with the low detection limit (39.8 nM) and exhibit excellent selectivity and sensitivity. The probe YBL has been applied to monitor intracellular ONOO- level fluctuations. Meanwhile, the image results showed that high sugar promoted the increase of ONOO- level in cells. More important, the probe YBL can be used for imaging in mice, and the results showed that content of ONOO- was increased in diabetic mice. Therefore, the probe YBL provided a tool for understanding diabetes progression by imaging ONOO-.


Subject(s)
Diabetes Mellitus, Experimental , Fluorescent Dyes , Fluorescent Dyes/chemistry , Fluorescent Dyes/chemical synthesis , Animals , Mice , Humans , Diabetes Mellitus, Experimental/chemically induced , Optical Imaging , Infrared Rays , Limit of Detection
17.
Phytomedicine ; 131: 155775, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38838401

ABSTRACT

BACKGROUND: The cyclin-dependent kinase 4 (CDK4) interacts with its canonical and non-canonical substrates modulating the cell cycle in tumor cells. However, the potential substrates and the beyond-cell-cycle-regulated functions of CDK4 in colon cancer (CC) are still unknown. Hernandezine (HER) is previously verified to induce G0/G1 phase arrest and autophagic cell death in human cancer cells, which implies that HER might target G0/G1 phase-related proteins, including CDK4. PURPOSE: The present study tried to investigate the glycolytic metabolism and oxidative stress functions of CDK4 in colon cancer. Furthermore, the inhibitory effects and potential binding sites of HER on CDK4, as well as its anti-tumor activity were investigated in CC cells. METHODS: The mass spectrometry assay was performed to identify potential endogenous substrates of CDK4 and the correlation between glycolytic metabolic rate and CDK4 level in COAD patient tissues. Meanwhile, after inhibiting the activity or the expression of CDK4, the binding capacity of CDK4 to PKM2 and NRF2 and the latter two protein distributions in cytoplasm and nucleus were detected in CC cells. In vitro, the regulatory effects of the CDK4-PKM2-NRF2 axis on glycolysis and oxidative stress were performed by ECAR, OCR, and ROS assay. The inhibitory effect of HER on CDK4 activity was explored in CC cells and the potential binding sites were predicted and testified in vitro. Furthermore, tumor growth inhibition of HER by suppressing the CDK4-PKM2-NRF2 axis was also investigated in vitro and in vivo. RESULTS: PKM2 and NRF2 were identified as endogenous substrates of CDK4 and, high-expressed CDK4 was associated with low-level glycolysis in COAD. In vitro, inactivated CDK4 facilitated CDK4-PKM2-NRF2 complex formation which resulted in 1) inhibited PKM2 activity and retarded the glycolytic rate; 2) cytoplasm-detained NRF2 failed to transcript anti-oxidative gene expressions and induced oxidant stress. Additionally, as a CDK4 inhibitor, HER developed triple anti-tumor effects including induced G0/G1 phase arrest, suppressed glycolysis, and disrupted the anti-oxidative capacity of CC cells. CONCLUSION: The results first time revealed that CDK4 modulated glycolytic and anti-oxidative capacity of CC cells via bound to its endogenous substrates, PKM2 and NRF2. Additionally, 140Asp145Asn amino acid sites of CDK4 were potential targets of HER. HER exerts anti-tumor activity by inhibited the activity of CDK4, promoted the CDK4-PKM2-NRF2 complex formation in the CC cells.


Subject(s)
Carrier Proteins , Colonic Neoplasms , Cyclin-Dependent Kinase 4 , Membrane Proteins , NF-E2-Related Factor 2 , Thyroid Hormone-Binding Proteins , Thyroid Hormones , NF-E2-Related Factor 2/metabolism , Humans , Cyclin-Dependent Kinase 4/metabolism , Colonic Neoplasms/drug therapy , Colonic Neoplasms/metabolism , Animals , Membrane Proteins/metabolism , Thyroid Hormones/metabolism , Cell Line, Tumor , Carrier Proteins/metabolism , Glycolysis/drug effects , Mice , Oxidative Stress/drug effects , Mice, Nude , Mice, Inbred BALB C , Female
18.
Ann Acad Med Singap ; 53(5): 306-317, 2024 May 10.
Article in English | MEDLINE | ID: mdl-38920222

ABSTRACT

Introduction: Preconception is a critical period to optimise gamete function and early placental development, essential for successful conception and long-term maternal-child health. However, there is a lack of preconception services and consequently, global fertility rates continue to fall and mothers embark on their pregnancy journey in poor health. There is an urgent need to implement a holistic community-level preconception care programme to optimise risk factors for poor fecundability and improve long-term maternal-child health. Method: We reviewed current evidence on fecundability lifestyle risk factors, the efficacy of existing preconception interventions and the use of digital platforms for health optimisation, to create a new digital-based preconception intervention model that will be implemented via an app. We present the theory, content and mode of delivery of this holistic model targeting couples planning for pregnancy. Results: We propose a new model featuring a user-friendly mobile app, which enables couples to self-assess fecundability risks through a personalised risk score that drives a tailored management plan. This tiered management provides anticipatory guidance supported by evidence-based recommen-dations, and promotes ongoing engagement for behavioural optimisation and specialist referrals as required. Based on the health belief model, this new model delivered with a mobile app seeks to shift couples' perceptions about their susceptibility and severity of subfertility, benefits of making a change and barriers to change. Conclusion: Our proposed digital-based intervention model via a mobile app stands to enhance preconcep-tion care by providing personalised risk assessments, real-time feedback and tiered management to optimise preconception reproductive health of couples. This model forms a reference content framework for future preconception care intervention delivery.


Subject(s)
Mobile Applications , Preconception Care , Humans , Preconception Care/methods , Female , Pregnancy , Holistic Health , Child Health , Fertility , Risk Factors , Maternal Health
19.
Adv Sci (Weinh) ; 11(30): e2400242, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38874525

ABSTRACT

Maxillofacial bone defects exhibit intricate anatomy and irregular morphology, presenting challenges for effective treatment. This study aimed to address these challenges by developing an injectable bioactive composite microsphere, termed D-P-Ak (polydopamine-PLGA-akermanite), designed to fit within the defect site while minimizing injury. The D-P-Ak microspheres biodegraded gradually, releasing calcium, magnesium, and silicon ions, which, notably, not only directly stimulated the osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs) but also activated sensory nerve cells to secrete calcitonin gene-related peptide (CGRP), a key factor in bone repair. Moreover, the released CGRP enhanced the osteogenic differentiation of BMSCs through epigenetic methylation modification. Specifically, inhibition of EZH2 and enhancement of KDM6A reduced the trimethylation level of histone 3 at lysine 27 (H3K27), thereby activating the transcription of osteogenic genes such as Runx2 and Osx. The efficacy of the bioactive microspheres in bone repair is validated in a rat mandibular defect model, demonstrating that peripheral nerve response facilitates bone regeneration through epigenetic modification. These findings illuminated a novel strategy for constructing neuroactive osteo-inductive biomaterials with potential for further clinical applications.


Subject(s)
Bone Regeneration , Mesenchymal Stem Cells , Microspheres , Osteogenesis , Animals , Rats , Mesenchymal Stem Cells/metabolism , Bone Regeneration/genetics , Bone Regeneration/drug effects , Bone Regeneration/physiology , Osteogenesis/physiology , Osteogenesis/genetics , Cell Differentiation , Demethylation , Rats, Sprague-Dawley , Disease Models, Animal , Ceramics , Histones/metabolism , Histones/genetics , Calcitonin Gene-Related Peptide/metabolism , Calcitonin Gene-Related Peptide/genetics , Male , Biocompatible Materials/metabolism
20.
Adv Mater ; 36(28): e2311758, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38758171

ABSTRACT

Thermoset elastomers have been extensively applied in many fields because of their excellent mechanical strengths and durable characteristics, such as an excellent chemical resistance. However, in the context of environmental issues, the nonrecyclability of thermosets has become a major barrier to the further development of these materials. Here, a well-tailored strategy is reported to solve this problem by introducing mismatched supramolecular interactions (MMSIs) into a covalently cross-linked poly(urethane-urea) network with dynamic acylsemicarbazide moieties. The MMSIs significantly strengthen and toughen the thermoset elastomer by effectively dissipating energy and resisting external stress. In addition, the elastomer recycling efficiency is improved 2.7-fold due to the superior reversibility of the MMSIs. The optimized thermoset elastomer features outstanding characteristics, including an ultrahigh tensile strength (110.8 MPa), an unprecedented tensile toughness (1245.2 MJ m-3), as well as remarkable resistance to chemical media, creep, and damage. Most importantly, it exhibits an extraordinary multirecyclability, and the 4th recycling efficiency remains close to 100%. This scalable method promotes the development of thermosets with both high performance and excellent recyclability, thereby providing valuable guidance for addressing the issue of nonrecyclability from a molecular design standpoint.

SELECTION OF CITATIONS
SEARCH DETAIL