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1.
Angew Chem Int Ed Engl ; : e202407037, 2024 May 20.
Article in English | MEDLINE | ID: mdl-38767062

ABSTRACT

The stimulator of interferon genes (STING) pathway is a potent therapeutic target for innate immunity. Despite the efforts to develop pocket-dependent small-molecule STING agonists that mimic the endogenous STING ligand, cyclic guanosine monophosphate-adenosine monophosphate (cGAMP), most of these agonists showed disappointing results in clinical trials owing to the limitations of the STING pocket. In this study, we developed novel pocket-independent STING-activating agonists (piSTINGs), which act through multivalency-driven oligomerization to activate STING. Additionally, a piSTING-adjuvanted vaccine elicited a significant antibody response and inhibited tumour growth in therapeutic models. Moreover, a piSTING-based vaccine combination with aPD-1 showed remarkable potential to enhance the effectiveness of immune checkpoint blockade (ICB) immunotherapy. In particular, piSTING can strengthen the impact of STING pathway in immunotherapy and accelerate the clinical translation of STING agonists.

2.
Radiother Oncol ; : 110333, 2024 May 19.
Article in English | MEDLINE | ID: mdl-38772478

ABSTRACT

BACKGROUND: Lymphopenia is known for its significance on poor survivals in breast cancer (BC) patients. Considering full dosimetric data, this study aimed to develop and validate predictive models for lymphopenia after radiotherapy (RT) in BC. MATERIAL AND METHODS: BC patients treated with adjuvant RT were eligible in this multicenter study. The study endpoint was lympopenia, defined as the reduction in absolute lymphocytes and graded lymphopenia after RT. The dose-volume histogram (DVH) data of related critical structures and clinical factors were taken into account for the development of dense neural network (DNN) predictive models. The developed DNN models were validated using external patient cohorts. RESULTS: Totally 918 consecutive patients with invasive BC enrolled. The training, testing, and external validating datasets consisted of 589, 203, and 126 patients, respectively. Treatment volumes at nearly all dose levels of the DVH were significant predictors for lymphopenia following RT, including volumes at very low-dose 1 Gy (V1) of organs at risk (OARs) including lung, heart and body, especially ipsilateral-lung V1. A final DNN model, combining full DVH dosimetric parameters of OARs and three key clinical factors, achieved a predictive accuracy of 75 % or higher. CONCLUSION: This study demonstrated and externally validated the significance of full dosimetric data, particularly the volume of low dose at as low as 1 Gy of critical structures on lymphopenia after radiation in BC patients. The significance of V1 deserves special attention, as modern VMAT RT technology often has a relatively high value of this parameter. Further study warranted for RT plan optimization.

3.
Adv Mater ; : e2404888, 2024 May 13.
Article in English | MEDLINE | ID: mdl-38738587

ABSTRACT

Confining luminophores into modified hydrophilic matrices or polymers is a straightforward and widely used approach for afterglow bioimaging. However, the afterglow quantum yield and lifetime of the related material remain unsatisfactory, severely limiting the using effect especially for deep-tissue time-resolved imaging. This fact largely stems from the dilemma between material biocompatibility and the quenching effect of water environment. Herein an in situ metathesis promoted doping strategy is presented, namely, mixing ≈10-3 weight ratio of organic-emitter multicarboxylates with inorganic salt reactants, followed by metathesis reactions to prepare a series of hydrophilic but water-insoluble organic-inorganic doping afterglow materials. This strategy leads to the formation of edible long-afterglow photoluminescent materials with superior biocompatibility and excellent bioimaging effect. The phosphorescence quantum yield of the materials can reach dozens of percent (the highest case: 66.24%), together with the photoluminescent lifetime lasting for coupes of seconds. Specifically, a long-afterglow barium meal formed by coronene salt emitter and BaSO4 matrix is applied into animal experiments by gavage, and bright stomach afterglow imaging is observed by instruments or mobile phone after ceasing the photoexcitation with deep tissue penetration. This strategy allows a flexible dosage of the materials during bioimaging, facilitating the development of real-time probing and theranostic technology.

4.
Environ Sci Technol ; 58(20): 8724-8735, 2024 May 21.
Article in English | MEDLINE | ID: mdl-38717952

ABSTRACT

Building and protecting soil organic carbon (SOC) are critical to agricultural productivity, soil health, and climate change mitigation. We aim to understand how mechanisms at the organo-mineral interfaces influence SOC persistence in three contrasting soils (Luvisol, Vertisol, and Calcisol) under long-term free air CO2 enrichment conditions. A continuous wheat-field pea-canola rotation was maintained. For the first time, we provided evidence to a novel notion that persistent SOC is molecularly simple even under elevated CO2 conditions. We found that the elevated CO2 condition did not change the total SOC content or C forms compared with the soils under ambient CO2 as identified by synchrotron-based soft X-ray analyses. Furthermore, synchrotron-based infrared microspectroscopy confirmed a two-dimensional microscale distribution of similar and less diverse C forms in intact microaggregates under long-term elevated CO2 conditions. Strong correlations between the distribution of C forms and O-H groups of clays can explain the steady state of the total SOC content. However, the correlations between C forms and clay minerals were weakened in the coarse-textured Calcisol under long-term elevated CO2. Our findings suggested that we should emphasize identifying management practices that increase the physical protection of SOC instead of increasing complexity of C. Such information is valuable in developing more accurate C prediction models under elevated CO2 conditions and shift our thinking in developing management practices for maintaining and building SOC for better soil fertility and future environmental sustainability.


Subject(s)
Carbon Dioxide , Carbon , Soil , Carbon Dioxide/chemistry , Soil/chemistry , Climate Change
5.
Adv Mater ; : e2401145, 2024 May 01.
Article in English | MEDLINE | ID: mdl-38692574

ABSTRACT

Photopyroptosis is an emerging research branch of photodynamic therapy (PDT), whereas there remains a lack of molecular structural principles to fabricate photosensitizers for triggering a highly efficient pyroptosis. Herein, a general and rational structural design principle to implement this hypothesis, is proposed. The principle relies on the clamping of cationic moieties (e.g., pyridinium, imidazolium) onto one photosensitive core to facilitate a considerable mitochondrial targeting (both of the inner and the outer membranes) of the molecules, thus maximizing the photogenerated reactive oxygen species (ROS) at the specific site to trigger the gasdermin E-mediated pyroptosis. Through this design, the pyroptotic trigger can be achieved in a minimum of 10 s of irradiation with a substantially low light dosage (0.4 J cm⁻2), compared to relevant work reported (up to 60 J cm⁻2). Moreover, immunotherapy with high tumor inhibition efficiency is realized by applying the synthetic molecules alone. This structural paradigm is valuable for deepening the understanding of PDT (especially the mitochondrial-targeted PDT) from the perspective of pyroptosis, toward the future development of the state-of-the-art form of PDT.

6.
Angew Chem Int Ed Engl ; : e202402880, 2024 May 17.
Article in English | MEDLINE | ID: mdl-38758629

ABSTRACT

Lysine-specific peptide and protein modification strategies are widely used to study charge-related functions and applications. However, these strategies often result in the loss of the positive charge on lysine, significantly impacting the charge-related properties of proteins. Herein, we report a strategy to preserve the positive charge and selectively convert amines in lysine side chains to amidines using nitriles and hydroxylamine under aqueous conditions. Various unprotected peptides and proteins were successfully modified with a high conversion rate. Moreover, the reactive amidine moiety and derived modification site enable subsequent secondary modifications. Notably, positive charges were retained during the modification. Therefore, positive charge-related protein properties, such as liquid‒liquid phase separation behaviour of α-synuclein, were not affected. This strategy was subsequently applied to a lysine rich protein to develop an amidine-containing coacervate DNA complex with outstanding mechanical properties. Overall, our innovative strategy provides a new avenue to explore the characteristics of positively charged proteins.

7.
J Am Chem Soc ; 2024 Apr 10.
Article in English | MEDLINE | ID: mdl-38597345

ABSTRACT

Deubiquitinase-targeting chimeras (DUBTACs) have been recently developed to stabilize proteins of interest, which is in contrast to targeted protein degradation (TPD) approaches that degrade disease-causing proteins. However, to date, only the OTUB1 deubiquitinase has been utilized to develop DUBTACs via an OTUB1 covalent ligand, which could unexpectedly compromise the endogenous function of OTUB1 owing to its covalent nature. Here, we show for the first time that deubiquitinase USP7 can be harnessed for DUBTAC development. Based on a noncovalent ligand of USP7, we developed USP7-based DUBTACs that stabilized the ΔF508-CFTR mutant protein as effectively as the previously reported OTUB1-based DUBTAC. Importantly, using two different noncovalent ligands of USP7, we developed the first AMPK DUBTACs that appear to selectively stabilize different isoforms of AMPKß, leading to elevated AMPK signaling. Overall, these results highlight that, in addition to OTUB1, USP7 can be leveraged to develop DUBTACs, thus significantly expanding the limited toolbox for targeted protein stabilization and the development of novel AMPK DUBTACs as potential therapeutics.

8.
J Burn Care Res ; 2024 Apr 15.
Article in English | MEDLINE | ID: mdl-38616525

ABSTRACT

Animal experiments are important in trauma-related studies because they simulate in vivo effects. Rodents are a good choice for preparing trauma models; however, contractile healing in rodents results in a healing pattern that differs considerably from that in humans. Therefore, this study developed a new rodent model that avoids contractile healing of the skin around the wound using an anti-contraction ring, and the skin in the wound's center remains intact and acts as a source for epithelialized diffusion healing. Cell proliferation, migration, revascularization, and collagen secretion did not differ between the novel and conventional full-skin defect trauma models. However, the healing rate at various stages significantly differed between the two groups owing to differences in the healing patterns. And without effective treatment, the experimental group cannot heal. The stabilities of the novel and conventional methods were good regardless of operator or batch. In summary, this new animal trauma model provides a stable experimental environment similar to that in humans, which may promote trauma-related research.

9.
Pediatr Rheumatol Online J ; 22(1): 42, 2024 Apr 12.
Article in English | MEDLINE | ID: mdl-38610057

ABSTRACT

BACKGROUND: Intravenous immunoglobulin (IVIG) is the primary treatment for Kawasaki disease (KD). However, 10-20% of KD patients show no response to IVIG treatment, making the early prediction of IVIG resistance a key focus of KD research. Our aim is to explore the application of the C-reactive protein to albumin ratio (CAR) for predicting IVIG resistance in children with KD through meta-analysis. METHODS: Cochrane Library, PubMed, MEDLINE, EMbase, CNKI, WanFang, the Chinese Biomedical Database, and CQVIP were searched up to November 2023 for cohort studies on predicting IVIG-resistant KD using the CAR. Articles were selected based on pre-established inclusion and exclusion criteria after extracting literature data and assessing them using the QUADAS-2.0 tool for evaluating the accuracy of diagnostic tests. Stata 15.0 software was used for meta-analysis. RESULTS: Four Chinese and English literature reports were included in this meta-analysis. The results revealed the presence of a threshold effect and high heterogeneity among the included studies. The combined sensitivity for CAR predicting IVIG-resistant KD was calculated as 0.65 (95% CI 0.58-0.72), specificity as 0.71 (95% CI 0.57-0.81), and the area under the curve (AUC) as 0.70 (95% CI 0.66-0.74) using the random-effects model. The combined positive likelihood ratio was 2.22 (95% CI 1.35-3.65), the combined negative likelihood ratio was 0.49 (95% CI 0.35-0.69), and the diagnostic odds ratio was 5 (95% CI 2-10). CONCLUSION: CAR is an auxiliary predictive indicator with moderate diagnostic value that provides guidance in the early treatment of the disease, demonstrating a certain predictive value that warrants further investigation. However, CAR cannot yet be considered as a definitive diagnostic or exclusionary marker for IVIG-resistant KD. Therefore, multi-center, large sample, and high-quality long-term follow-up trials are warranted to confirm the current findings.


Subject(s)
C-Reactive Protein , Mucocutaneous Lymph Node Syndrome , Child , Humans , Albumins , Cohort Studies , Immunoglobulins, Intravenous/pharmacology , Immunoglobulins, Intravenous/therapeutic use , Mucocutaneous Lymph Node Syndrome/diagnosis , Mucocutaneous Lymph Node Syndrome/drug therapy , Prognosis
10.
Nature ; 628(8008): 664-671, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38600377

ABSTRACT

Bitter taste sensing is mediated by type 2 taste receptors (TAS2Rs (also known as T2Rs)), which represent a distinct class of G-protein-coupled receptors1. Among the 26 members of the TAS2Rs, TAS2R14 is highly expressed in extraoral tissues and mediates the responses to more than 100 structurally diverse tastants2-6, although the molecular mechanisms for recognizing diverse chemicals and initiating cellular signalling are still poorly understood. Here we report two cryo-electron microscopy structures for TAS2R14 complexed with Ggust (also known as gustducin) and Gi1. Both structures have an orthosteric binding pocket occupied by endogenous cholesterol as well as an intracellular allosteric site bound by the bitter tastant cmpd28.1, including a direct interaction with the α5 helix of Ggust and Gi1. Computational and biochemical studies validate both ligand interactions. Our functional analysis identified cholesterol as an orthosteric agonist and the bitter tastant cmpd28.1 as a positive allosteric modulator with direct agonist activity at TAS2R14. Moreover, the orthosteric pocket is connected to the allosteric site via an elongated cavity, which has a hydrophobic core rich in aromatic residues. Our findings provide insights into the ligand recognition of bitter taste receptors and suggest activities of TAS2R14 beyond bitter taste perception via intracellular allosteric tastants.


Subject(s)
Cholesterol , Intracellular Space , Receptors, G-Protein-Coupled , Taste , Humans , Allosteric Regulation/drug effects , Allosteric Site , Cholesterol/chemistry , Cholesterol/metabolism , Cholesterol/pharmacology , Cryoelectron Microscopy , Hydrophobic and Hydrophilic Interactions , Intracellular Space/chemistry , Intracellular Space/metabolism , Ligands , Receptors, G-Protein-Coupled/agonists , Receptors, G-Protein-Coupled/chemistry , Receptors, G-Protein-Coupled/metabolism , Receptors, G-Protein-Coupled/ultrastructure , Reproducibility of Results , Taste/drug effects , Taste/physiology , Transducin/chemistry , Transducin/metabolism , Transducin/ultrastructure
11.
Front Bioeng Biotechnol ; 12: 1347995, 2024.
Article in English | MEDLINE | ID: mdl-38628439

ABSTRACT

The tissues or organs derived decellularized extracellular matrix carry immunogenicity and the risk of pathogen transmission, resulting in limited therapeutic effects. The cell derived dECM cultured in vitro can address these potential risks, but its impact on wound remodeling is still unclear. This study aimed to explore the role of decellularized extracellular matrix (dECM) extracted from adipose derived stem cells (ADSCs) in skin regeneration. Methods: ADSCs were extracted from human adipose tissue. Then we cultivated adipose-derived stem cell cells and decellularized ADSC-dECM for freeze-drying. Western blot (WB), enzyme-linked immunosorbent assay (ELISA) and mass spectrometry (MS) were conducted to analyzed the main protein components in ADSC-dECM. The cell counting assay (CCK-8) and scratch assay were used to explore the effects of different concentrations of ADSC-dECM on the proliferation and migration of human keratinocytes cells (HaCaT), human umbilical vein endothelia cells (HUVEC) and human fibroblasts (HFB), respectively. Moreover, we designed a novel ADSC-dECM-CMC patch which used carboxymethylcellulose (CMC) to load with ADSC-dECM; and we further investigated its effect on a mouse full thickness skin wound model. Results: ADSC-dECM was obtained after decellularization of in vitro cultured human ADSCs. Western blot, ELISA and mass spectrometry results showed that ADSC-dECM contained various bioactive molecules, including collagen, elastin, laminin, and various growth factors. CCK-8 and scratch assay showed that ADSC-dECM treatment could significantly promote the proliferation and migration of HaCaT, human umbilical vein endothelia cells, and human fibroblasts, respectively. To evaluate the therapeutic effect on wound healing in vivo, we developed a novel ADSC-dECM-CMC patch and transplanted it into a mouse full-thickness skin wound model. And we found that ADSC-dECM-CMC patch treatment significantly accelerated the wound closure with time. Further histology and immunohistochemistry indicated that ADSC-dECM-CMC patch could promote tissue regeneration, as confirmed via enhanced angiogenesis and high cell proliferative activity. Conclusion: In this study, we developed a novel ADSC-dECM-CMC patch containing multiple bioactive molecules and exhibiting good biocompatibility for skin reconstruction and regeneration. This patch provides a new approach for the use of adipose stem cells in skin tissue engineering.

12.
J Med Chem ; 67(8): 6880-6892, 2024 Apr 25.
Article in English | MEDLINE | ID: mdl-38607318

ABSTRACT

Bridged PROTAC is a novel protein complex degrader strategy that exploits the target protein's binding partner to degrade undruggable proteins by inducing proximity to an E3 ubiquitin ligase. In this study, we discovered for the first time that cereblon (CRBN) can be employed for the bridged PROTAC approach and report the first-in-class CRBN-recruiting and EED-binding polycomb repressive complex 1 (PRC1) degrader, compound 1 (MS181). We show that 1 induces preferential degradation of PRC1 components, BMI1 and RING1B, in an EED-, CRBN-, and ubiquitin-proteosome system (UPS)-dependent manner. Compound 1 also has superior antiproliferative activity in multiple metastatic cancer cell lines over EED-binding PRC2 degraders and can be efficacious in VHL-defective cancer cells. Altogether, compound 1 is a valuable chemical biology tool to study the role of PRC1 in cancer. Importantly, we show that CRBN can be utilized to develop bridged PROTACs, expanding the bridged PROTAC technology for degrading undruggable proteins.


Subject(s)
Adaptor Proteins, Signal Transducing , Polycomb Repressive Complex 1 , Proteolysis , Ubiquitin-Protein Ligases , Humans , Ubiquitin-Protein Ligases/metabolism , Polycomb Repressive Complex 1/metabolism , Polycomb Repressive Complex 1/antagonists & inhibitors , Adaptor Proteins, Signal Transducing/metabolism , Cell Line, Tumor , Proteolysis/drug effects , Drug Discovery , Antineoplastic Agents/pharmacology , Antineoplastic Agents/chemistry , Antineoplastic Agents/chemical synthesis , Cell Proliferation/drug effects , Structure-Activity Relationship
13.
Vascular ; : 17085381241249288, 2024 Apr 26.
Article in English | MEDLINE | ID: mdl-38670962

ABSTRACT

BACKGROUND: Endovenous interventions and minimally invasive procedures are effective in the management of varicose veins. However, they can cause postoperative discomfort. OBJECTIVE: To evaluate the clinical efficacy of sodium aescinate (SA) in improving edema, pain, vein-specific symptoms, and quality of life in patients following endovenous laser ablation (EVLA) for varicose veins. METHODS: In this single-center randomized controlled trial (RCT), patients were allocated into two groups: in Group A, 60 mg SA was administered twice daily for 20 days, and in Group B (control), no venoactive drug was prescribed. The Clinical-Etiology-Anatomy-Pathophysiology (CEAP) classification system for chronic venous disorders was used to assess the varicose veins. The circumferences of the calf and ankle were recorded for evaluating edema. The 10-point Visual Analog Scale (VAS), Venous Clinical Severity Score (VCSS), and Aberdeen Varicose Veins Questionnaire (AVVQ) were used to measure the pain intensity, overall varicose vein severity, and patient's quality of life, respectively. RESULTS: The study included 87 patients (mean age, 59.9 ± 10.7 years; 54 men) with CEAP class C2-C5 varicose veins who underwent EVLA and phlebectomy or foam sclerotherapy. The calf circumference recovered quicker in Group A than in Group B by days 10, 21, and 30 (difference from baseline was 1.04 ± 0.35 vs 2.39 ± 1.15 [p < .001], 0.48 ± 0.42 vs1.73 ± 1.00 [p < .001], and 0.18 ± 0.64 vs 0.82 ± 0.96 [p < .001], respectively). The ankle circumference recovered quicker in Group A than in Group B by days 10 and 21 (the difference from baseline was 1.37 ± 0.52 vs 2.36 ± 0.93 [p < .001] and 0.58 ± 0.60 vs 1.14 ± 0.88 [p = .002], respectively). Pain relief was achieved quicker in Group A than in Group B (0.257 ± 1.097 [p = .0863] vs 0.506 ± 1.250 [p = .0168] by day 21). There were no significant differences in the VCSS and AVVQ scores between both groups. There were no drug-related adverse effects. CONCLUSIONS: SA, in combination with compression therapy, can relieve edema and alleviate pain in patients following EVLA for varicose veins.

14.
J Med Chem ; 67(8): 6397-6409, 2024 Apr 25.
Article in English | MEDLINE | ID: mdl-38602846

ABSTRACT

Aberrantly expressed lysine methyltransferases G9a and GLP, which catalyze mono- and dimethylation of histone H3 lysine 9 (H3K9), have been implicated in numerous cancers. Recent studies have uncovered both catalytic and noncatalytic oncogenic functions of G9a/GLP. As such, G9a/GLP catalytic inhibitors have displayed limited anticancer activity. Here, we report the discovery of the first-in-class G9a/GLP proteolysis targeting chimera (PROTAC) degrader 10 (MS8709), as a potential anticancer therapeutic. 10 induces G9a/GLP degradation in a concentration-, time-, and ubiquitin-proteasome system (UPS)-dependent manner. Futhermore, 10 does not alter the mRNA expression of G9a/GLP and is selective for G9a/GLP over other methyltransferases. Moreover, 10 displays superior cell growth inhibition to the parent G9a/GLP inhibitor UNC0642 in prostate, leukemia, and lung cancer cells and has suitable mouse pharmacokinetic properties for in vivo efficacy studies. Overall, 10 is a valuable chemical biology tool to further investigate the functions of G9a/GLP and a potential therapeutic for treating G9a/GLP-dependent cancers.


Subject(s)
Antineoplastic Agents , Histone-Lysine N-Methyltransferase , Histone-Lysine N-Methyltransferase/antagonists & inhibitors , Histone-Lysine N-Methyltransferase/metabolism , Humans , Animals , Antineoplastic Agents/pharmacology , Antineoplastic Agents/chemistry , Antineoplastic Agents/chemical synthesis , Mice , Cell Line, Tumor , Proteolysis/drug effects , Histocompatibility Antigens/metabolism , Drug Discovery , Cell Proliferation/drug effects , Male , Structure-Activity Relationship
15.
Article in English | MEDLINE | ID: mdl-38625452

ABSTRACT

We examined the integrity of flash-frozen and cryo-sectioned cardiac muscle preparations (introduced by Feng and Jin, 2020) by assessing tension transients in response to sinusoidal length changes at varying frequencies (1-100 Hz) at 25 °C. Using 70-µm-thick sections, we isolated fiber preparations to study cross-bridge (CB) kinetics: preparations were activated by saturating Ca2+ as well as varying concentrations of ATP and phosphate (Pi). Our results showed that, compared to ordinary skinned fibers, in-series stiffness decreased to 1/2, which resulted in a decrease of isometric tension to 62%, but CB kinetics and Ca2+ sensitivity were little affected. The pCa study demonstrated that the rate constant of the force generation step (2πb) is proportionate to [Ca2+] at < 5 µM, suggesting that the activation mechanism can be described by a simple second order reaction. We also found that tension, stiffness, and magnitude parameters are related to [Ca2+] by the Hill equation, with a cooperativity coefficient of 4-5, which is consistent with the fact that Ca2+ activation mechanisms involve cooperative multimolecular interactions. Our results support the long-held hypothesis that Process C (Phase 2) represents the CB detachment step, and Process B (Phase 3) represents the force generation step. Moreover, we discovered that constant H may represent the work-performing step in cardiac preparations. Our experiments demonstrate excellent CB kinetics with two well-defined exponentials that can be more distinguished than those found using ordinary skinned fibers. Flash-frozen and cryo-sectioned preparations are especially suitable for multi-institutional collaborations nationally and internationally because of their ease of transportation.

16.
Polymers (Basel) ; 16(8)2024 Apr 22.
Article in English | MEDLINE | ID: mdl-38675096

ABSTRACT

The polar sulfonate groups in cationic dyeable polyester (CDP) lead to complex crystallization behavior, affecting CDP production's stability. In this study, cationic dyeable polyesters (CDP) with different sulfonate group contents were prepared via one-step feeding of sodium isophthalic acid-5-sulfonate (SIPA), terephthalic acid (PTA), and ethylene glycol (EG). The non-isothermal crystallization behavior of these copolyesters was analyzed by differential scanning calorimetry (DSC). Results show that the crystallization temperature of the sample shifts to lower values with the increase in SIPA content. The relaxation behavior of the molecular chain is enhanced due to the ionic aggregation effect of sulfonate groups in CDP. Therefore, at low cooling rates (2.5 °C/min and 5 °C/min), some molecular chain segments in CDP are still too late to orderly stack into the lattice, forming metastable crystals, and melting double peaks appear on the melting curve after crystallization. When the cooling rate increases (10-20 °C/min), the limited region of sulfonate aggregation in CDP increases, resulting in more random chain segments, and a cold crystallization peak appears on the melting curve after crystallization. The non-isothermal crystallization behavior of all samples was fitted and analyzed by the Jeziorny equation, Ozawa equation, and Mo equation. The results indicate that the nucleation density and nucleation growth rate of CDP decrease with the increase in SIPA content. Meanwhile, analysis of the Kissinger equation reveals that the activation energy of non-isothermal crystallization decreases gradually with the increase in SIPA content, and the addition of SIPA makes CDP crystallization more difficult.

17.
Biomed Pharmacother ; 174: 116579, 2024 May.
Article in English | MEDLINE | ID: mdl-38631145

ABSTRACT

BACKGROUND AND AIM: Diabetes-associated cognitive impairment (DCI) is a prevalent complication of diabetes. However, there is a lack of viable strategies for preventing and treating DCI. This study aims to explore the efficacy of baicalin (Bai) in attenuating DCI and elucidating the underlying mechanisms. EXPERIMENTAL PROCEDURE: GK rats fed a high-fat and high-glucose diet were utilized to investigate the therapeutic potential of Bai. Cognitive function was assessed using the Morris water maze and novel object recognition tests. To gain insight into the molecular mechanisms underlying Bai's neuro-protective effects, co-cultured BV2/HT22 cells were established under high-glucose (HG) stimulation. The modes of action of Bai were subsequently confirmed in vivo using the DCI model in db/db mice. KEY RESULTS: Bai restored cognitive and spatial memory and attenuated neuron loss, along with reducing expressions of Aß and phosphorylated Tau protein in diabetic GK rats. At the cellular level, Bai exhibited potent antioxidant and anti-inflammatory effects against HG stimulation. These effects were associated with the upregulation of Nrf2 and supressed Keap1 levels. Consistent with these in vitro findings, similar mechanisms were observed in db/db mice. The significant neuroprotective effects of Bai were abolished when co-administered with ATRA, a Nrf2 blocker, in db/db mice, confirming that KEAP1-Nrf2 signaling pathway was responsible for the observed effect. CONCLUSIONS AND IMPLICATIONS: Bai demonstrates a great therapeutic potential for attenuating DCI. The antioxidant defense and anti-inflammatory actions of Bai were mediated through the KEAP1-Nrf2 axis. These findings advance our understanding of potential treatment approaches for DCI, a common complication associated with diabetes.


Subject(s)
Cognitive Dysfunction , Flavonoids , NF-E2-Related Factor 2 , Neuroprotective Agents , Signal Transduction , Up-Regulation , Animals , Male , Mice , Rats , Antioxidants/pharmacology , Cell Line , Cognitive Dysfunction/drug therapy , Cognitive Dysfunction/etiology , Cognitive Dysfunction/metabolism , Diabetes Mellitus, Experimental/complications , Diabetes Mellitus, Experimental/drug therapy , Flavonoids/pharmacology , Flavonoids/therapeutic use , Kelch-Like ECH-Associated Protein 1/metabolism , Neuroprotective Agents/pharmacology , Neuroprotective Agents/therapeutic use , NF-E2-Related Factor 2/metabolism , Rats, Wistar , Signal Transduction/drug effects , Up-Regulation/drug effects
18.
Acta Pharmacol Sin ; 2024 Apr 12.
Article in English | MEDLINE | ID: mdl-38609562

ABSTRACT

Signal transducer and activator of transcription 3 (STAT3) plays an important role in the occurrence and progression of tumors, leading to resistance and poor prognosis. Activation of STAT3 signaling is frequently detected in hepatocellular carcinoma (HCC), but potent and less toxic STAT3 inhibitors have not been discovered. Here, based on antisense technology, we designed a series of stabilized modified antisense oligonucleotides targeting STAT3 mRNA (STAT3 ASOs). Treatment with STAT3 ASOs decreased the STAT3 mRNA and protein levels in HCC cells. STAT3 ASOs significantly inhibited the proliferation, survival, migration, and invasion of cancer cells by specifically perturbing STAT3 signaling. Treatment with STAT3 ASOs decreased the tumor burden in an HCC xenograft model. Moreover, aberrant STAT3 signaling activation is one of multiple signaling pathways involved in sorafenib resistance in HCC. STAT3 ASOs effectively sensitized resistant HCC cell lines to sorafenib in vitro and improved the inhibitory potency of sorafenib in a resistant HCC xenograft model. The developed STAT3 ASOs enrich the tools capable of targeting STAT3 and modulating STAT3 activity, serve as a promising strategy for treating HCC and other STAT3-addicted tumors, and alleviate the acquired resistance to sorafenib in HCC patients. A series of novel STAT3 antisense oligonucleotide were designed and showed potent anti-cancer efficacy in hepatocellular carcinoma in vitro and in vivo by targeting STAT3 signaling. Moreover, the selected STAT3 ASOs enhance sorafenib sensitivity in resistant cell model and xenograft model.

19.
ChemSusChem ; : e202400160, 2024 Apr 10.
Article in English | MEDLINE | ID: mdl-38596908

ABSTRACT

Capturing carbon dioxide (CO2) from flue gases is a crucial step towards reducing CO2 emissions. Among the various carbon capture methods, facilitated transport membranes (FTMs) have emerged as a promising technology for CO2 capture owing to their high efficiency and low energy consumption in separating CO2. However, FTMs still face the challenge of losing mobile carriers due to weak interaction between the carriers and membrane matrix. Herein, we report a sulfonated chitosan (SCS) gel membrane with confined amine carriers for effective CO2 capture. In this structure, diethylenetriamine (DETA) as a CO2-mobile carrier is confined within the SCS gel membrane via electrostatic forces, which can react reversibly with CO2 and thus greatly facilitate its transport. The SCS ion gel membrane allows for the fast diffusion of amine carriers within it while blocking the diffusion of nonreactive gases, like N2. Thus, the prepared membrane exhibits exceptional CO2 separation capabilities when tested under simulated flue gas conditions with CO2 permeance of 1155 GPU and an ultra-high CO2/N2 selectivity of above 550. Moreover, the membrane retains a stable separation performance during the 170 h continuous test. The excellent CO2 separation performance demonstrates the high potential of gel membranes for CO2 capture from flue gas.

20.
J Am Chem Soc ; 146(11): 7584-7593, 2024 Mar 20.
Article in English | MEDLINE | ID: mdl-38469801

ABSTRACT

Given the prevalent advancements in DNA- and RNA-based PROTACs, there remains a significant need for the exploration and expansion of more specific DNA-based tools, thus broadening the scope and repertoire of DNA-based PROTACs. Unlike conventional A- or B-form DNA, Z-form DNA is a configuration that exclusively manifests itself under specific stress conditions and with specific target sequences, which can be recognized by specific reader proteins, such as ADAR1 or ZBP1, to exert downstream biological functions. The core of our innovation lies in the strategic engagement of Z-form DNA with ADAR1 and its degradation is achieved by leveraging a VHL ligand conjugated to Z-form DNA to recruit the E3 ligase. This ingenious construct engendered a series of Z-PROTACs, which we utilized to selectively degrade the Z-DNA-binding protein ADAR1, a molecule that is frequently overexpressed in cancer cells. This meticulously orchestrated approach triggers a cascade of PANoptotic events, notably encompassing apoptosis and necroptosis, by mitigating the blocking effect of ADAR1 on ZBP1, particularly in cancer cells compared with normal cells. Moreover, the Z-PROTAC design exhibits a pronounced predilection for ADAR1, as opposed to other Z-DNA readers, such as ZBP1. As such, Z-PROTAC likely elicits a positive immunological response, subsequently leading to a synergistic augmentation of cancer cell death. In summary, the Z-DNA-based PROTAC (Z-PROTAC) approach introduces a modality generated by the conformational change from B- to Z-form DNA, which harnesses the structural specificity intrinsic to potentiate a selective degradation strategy. This methodology is an inspiring conduit for the advancement of PROTAC-based therapeutic modalities, underscoring its potential for selectivity within the therapeutic landscape of PROTACs to target undruggable proteins.


Subject(s)
DNA, Z-Form , Proteolysis Targeting Chimera , Proteolysis , Adenosine Deaminase/metabolism , RNA/metabolism , Ubiquitin-Protein Ligases/metabolism , DNA-Binding Proteins/metabolism
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