Dual Activity Research Articles

The effect of LINC9137 targeting miR-140-3p-NKAIN3 signal axis on the development of goose testis sertoli cells

Sertoli cells (SC) are a type of important cells in the testes, which can provide transport proteins, regulatory proteins, growth factors, and other cytokines for the spermatogenic process. They participate in the regulation of the maturation and differentiation of spermatogenic cells and play an important supporting role in the migration, proliferation, and differentiation of germ cells at all levels in the testes. Previous studies found differential expression of LINC9137, miR-140-3p, and Sodium/Potassium Transporting ATPase Interacting 3 (NKAIN3) genesin high and low sperm motility goose testicular tissues. This study investigated the effects of the LINC9137-miR-140-3p-NKAIN3 signal axis on the proliferation and apoptosis of goose testicular sertoli cells at the cellular level, respectively. The results showed that through acridine orange staining, oil red O staining, Alkaline phosphatase (AKP) staining, and RT qPCR assay, it was comprehensively identified that the cultured testicular sertoli cells were purified in vitro. Through the dual luciferase activity detection test, it was found that LINC9137 has a targeted binding site with miR-140-3p and NKAIN3. In addition, this study found that overexpression of miR-140-3p significantly inhibited the expression of LINC9137 and NKAIN3 in sertoli cells, and their expression was significantly increased when miR-140-3p was interfered with. By measuring cell proliferation activity and apoptosis related gene expression, it was found that overexpression of LINC9137 decreased cell proliferation activity (P > 0.05), while the expression level of apoptosis factor Bcl2 Associated X Protein (Bax)/B-cell lymphoma-2 (Bcl2) increased (P > 0.05). On the contrary, when interfering with LINC9137, the cell proliferation activity of sertoli cells was significantly increased (P < 0.01), and the expression level of apoptosis factor Bax/Bcl2 was significantly reduced (P < 0.05); The effect of miR-140-3p on the proliferation and apoptosis of sertoli cells is opposite to that of LINC9137. Meanwhile, this study co transfected overexpressed LINC9137 and miR-140-3p plasmids into sertoli cells, and found that the effect of LINC9137 overexpression on supporting cell proliferation was weakened by miR-140-3p. This study elucidates the role and function of the LINC9137 miR-140-3p-NKAIN3 signaling axis in the development of goose testes and spermatogenesis, establishes a regulatory network related to spermatogenesis, and provides a theoretical basis for studying the genetic regulation of goose spermatogenesis.

Advancing Photodynamic Antimicrobial Strategy: Sustainable Fabrication of Novel Lauryl Gallate-Chitosan Hydrophobic Films with Rapid Bacterial Capture and Biofilms Elimination Capabilities for Promoting Wound Healing.

Bioinspired photoactive composites, in terms of photodynamic inactivation, cost-effectiveness, and biosafety, are promising alternatives to antibiotics for combating bacterial infections while avoiding antibacterial resistance. However, the weak bacterial membrane affinity of the photoactive substrate and the lack of synergistic antibacterial effect remain crucial shortcomings for their antibacterial applications. Herein, we developed a hydrophobic film from food antioxidant lauryl gallate covalently functionalized chitosan (LG-g-CS conjugates) through a green radical-induced grafting reaction that utilizes synergistic bacteria capture, contact-killing, and photodynamic inactivation activities to achieve enhanced bactericidal and biofilm elimination capabilities. Besides, the grafting reaction mechanism between LG and CS in the ascorbic acid (AA)/H2O2 redox system was further proposed. The LG-g-CS films feature hydrophobic side chains and photoactive phenolic hydroxyl groups, facilitating dual bactericidal activities through bacteria capture and contact-killing via strong hydrophobic and electrostatic interactions with bacterial membranes as well as blue light (BL)-driven photodynamic bacterial eradication through the enhanced generation of reactive oxygen species. As a result, the LG-g-CS films efficiently capture and immobilize bacteria and exhibit excellent photodynamic antibacterial activity against model bacteria (Escherichia coli and Staphylococcus aureus) and their biofilms under BL irradiation. Moreover, LG-g-CS films could significantly promote the healing process of S. aureus-infected wounds. This research demonstrates a new strategy for designing and fabricating sustainable bactericidal and biofilm-removing materials with a high bacterial membrane affinity and photodynamic activity.

Valorization of oil palm empty fruit bunches into activated carbon: A mini-review

This paper aimed to comprehensively review the potential valorization of oil palm empty fruit bunches (OPEFBs) into activated carbon and its potential application. Activated carbon is carbon processed through dual phases, including carbonization and activation. Firstly, this process converts biomass into carbon thermally with zero to little oxygen conditions. Next, the carbon needs to be activated to stimulate the formation of pores and reduce impurities. The activated carbon’s quality is influenced by the activation process, which can be done physically, chemically, or physiochemically. Activated carbon has an amorphous structure and abundant internal pore structure, thus increasing the surface area. In Indonesia, the quality of active carbon is regulated by Indonesian National Standards or SNI 06-370-1995. The factors influencing the activation step include activator agent type, activator agent concentration, activation ratio and time, etc. . Generally, activated carbon can be widely applied to various sectors, such as agriculture (i.e., slow-released fertilizer, fertilizer, etc.), waste treatment (i.e., adsorbent, activator in anaerobic digestion/AD, bioremediation, etc.), gas purification, ceramic membrane, etc. However, further in-depth investigation is required to determine potential scaling-up and commercialization.

Simultaneous Dual-Activation Nitrogen-Enriched carbon aerogel for efficient adsorption of tetracycline from water

Aerogel materials are widely used for removing water pollutants due to their low density and three-dimensional porous structure. However, conventional aerogels still suffer from inadequate adsorption due to limited pore structure and functional groups. This study combined the benefits of efficient adsorption from porous carbon with the easy separation characteristics of aerogels. Using biomass-derived sodium alginate (SA) as precursor and a dual activation system of K2CO3 and melamine (MEL), we developed a macro nitrogen-enriched carbon aerogel (CAKN) with superior pore architecture and enriched surface functional groups, which realizes efficient adsorption of tetracycline (TC) and solves the problem of poor adsorption performance of aerogel materials. Results showed that CAKN prepared under optimal conditions reached a saturation adsorption capacity of 302.0 mg g−1, 2.7 folds of non-dual activated carbon aerogels (CA). This improvement stemmed from the dual activation of K2CO3 and MEL, resulting in more microporous and mesoporous structures and introducing nitrogenous groups that enhance the surface active sites. This study developed an environmentally friendly, interference-resistant, and regenerative strongly nitrogen-enriched carbon aerogel, and nitrogen doping demonstrates excellent performance, suggesting potential applications for other porous carbon modification strategies in aerogels.

Discovery of Clinical Candidate GLPG3970: A Potent and Selective Dual SIK2/SIK3 Inhibitor for the Treatment of Autoimmune and Inflammatory Diseases.

The salt-inducible kinases (SIKs) SIK1, SIK2, and SIK3 belong to the adenosine monophosphate-activated protein kinase (AMPK) family of serine/threonine kinases. SIK inhibition represents a new therapeutic approach modulating pro-inflammatory and immunoregulatory pathways that holds potential for the treatment of inflammatory diseases. Here, we describe the identification of GLPG3970 (32), a first-in-class dual SIK2/SIK3 inhibitor with selectivity against SIK1 (IC50 of 282.8 nM on SIK1, 7.8 nM on SIK2 and 3.8 nM on SIK3). We outline efforts made to increase selectivity against SIK1 and improve CYP time-dependent inhibition properties through the structure-activity relationship. The dual activity of 32 in modulating the pro-inflammatory cytokine TNFα and the immunoregulatory cytokine IL-10 is demonstrated in vitro in human primary myeloid cells and human whole blood, and in vivo in mice stimulated with lipopolysaccharide. Compound 32 shows dose-dependent activity in disease-relevant mouse pharmacological models.

Dual Activity of Type III PI3K Kinase Vps34 is Critical for NK Cell Development and Senescence.

Vps34 is the unique member of the class III phosphoinositide 3-kinase family that performs both vesicular transport and autophagy. Its role in natural killer (NK) cells remains uncertain. In this study, a model without Vps34 (Vps34fl/fl/CD122Cre/+) is generated, deleting Vps34 during and after NK-cell commitment. These mice exhibit a nearly 90% decrease in NK cell count and impaired differentiation. A mechanistic study reveals that the absence of Vps34 disrupts the transport of IL-15 receptor subunit alpha CD122 to the cell membrane, resulting in reduced responsiveness of NK cells to IL-15. In mice lacking Vps34 at the terminal stage of NK-cell development (Vps34fl/fl/Ncr1Cre/+), NK cells gradually diminish during aging. This phenotype is associated with autophagy deficiency and the stress induced by reactive oxygen species (ROS). Therefore, terminally differentiated NK cells lacking Vps34 display an accelerated senescence phenotype, while the application of antioxidants effectively reverses the senescence caused by Vps34 deletion by neutralizing ROS. In summary, this study unveils the dual and unique activity of Vps34 in NK cells. Vps34-mediated vesicular transport is crucial for CD122 membrane trafficking during NK cell commitment, whereas Vps34-mediated autophagy can delay NK cell senescence.

Structure of the intact tail machine of Anabaena myophage A-1(L)

The Myoviridae cyanophage A-1(L) specifically infects the model cyanobacteria Anabaena sp. PCC 7120. Following our recent report on the capsid structure of A-1(L), here we present the high-resolution cryo-EM structure of its intact tail machine including the neck, tail and attached fibers. Besides the dodecameric portal, the neck contains a canonical hexamer connected to a unique pentadecamer that anchors five extended bead-chain-like neck fibers. The 1045-Å-long contractile tail is composed of a helical bundle of tape measure proteins surrounded by a layer of tube proteins and a layer of sheath proteins, ended with a five-component baseplate. The six long and six short tail fibers are folded back pairwise, each with one end anchoring to the baseplate and the distal end pointing to the capsid. Structural analysis combined with biochemical assays further enable us to identify the dual hydrolytic activities of the baseplate hub, in addition to two host receptor binding domains in the tail fibers. Moreover, the structure of the intact A-1(L) also helps us to reannotate its genome. These findings will facilitate the application of A-1(L) as a chassis cyanophage in synthetic biology.

Abstract 7172: Pharmacokinetic/biomarker (PK/BMx) analysis of the toll-like receptor 7 and 8 (TLR7/8) agonist EIK1001 in phase 1 studies in participants (Pts) with solid tumors

Abstract Introduction: Immune checkpoint inhibitors (ICIs) relieve immunosuppression of tumor-reactive T cells and enhance antitumor immune response; however, not all patients benefit and some become refractory. EIK1001 is a TLR7/8 agonist that stimulates myeloid and plasmacytoid dendritic cells, activating immune and inflammatory responses. This dual activity provides another pathway, distinct from effects on checkpoint proteins, to enhance antitumor T-cell activity alone or in combination with ICIs. Methods: Adults with advanced solid tumors received a range of doses of EIK1001 (QW IV) alone and in combination with pembrolizumab (200 mg Q3W; NCT03486301) or atezolizumab (1200 mg Q3W; NCT04196530) in Phase 1 studies (n=128). PK samples were collected on Cycle 1 Day 1 (C1D1) and C1D8 predose and at 0.5, 1, 2, 4, 6, 8, 12, and 24 hrs postdose, with sparse sampling thereafter. Matched cytokine BMx samples were collected. The PK analysis population comprised pts with at least one measurable EIK1001 concentration (1563 observations from 94 pts). PK data were analyzed using non-linear mixed effects in Phoenix (v8.3). Covariate effects of the combination drugs were tested using a stepwise approach with a significance level of 0.05 for forward addition. All other covariates were evaluated using exploratory plots and formally tested using a full matrix approach. Empirical Bayes estimates were used to generate individual steady-state concentration-time profiles and calculate post-hoc PK parameters. Exploratory analyses of exposure-safety and exposure-efficacy were conducted. Results: EIK1001 PK was linear and dose-proportional over the doses studied. Tmax ranged from 4-12 hrs with no accumulation. Pop-PK analysis indicated that body size influenced clearance, but intrinsic factors of age, gender, tumor type, ECOG status, or hepatic/renal impairment (mild/moderate) did not. Combination drugs did not influence clearance. These attributes support BSA-based dosing and inform inclusion/exclusion criteria for future studies. On C1D1, time-dependent increases in IL-6, IL-8, IFNγ, and IP-10 returned to baseline within 24 hrs. An earlier IL-8 increase (Tmax 3-5 hr) is consistent with TLR8 activation on various cells including neutrophils, whereas the delayed increase of IFNγ/IP-10 (Tmax 5-8 hr) suggests a downstream effect. Dose-dependent increases in cytokines were observed, with median peak changes from baseline of 1.13- to 7.97-fold for IFNγ and 0.63- to 12.1-fold for IP-10. The 2 highest doses provided evidence of robust target engagement alone or in combination. Conclusion: The linear, dose-proportional PK of EIK1001 is well described by the Pop-PK model. Increases in IFNγ and IP-10 were consistent with the anticipated mechanism of action, with doses representing target engagement identified. Further development of EIK1001 is underway. Citation Format: Drew Rasco, Manish Patel, Melissa Johnson, Anthony Tolcher, David Sommerhalder, Omid Hamid, Angela Alistar, Jarema Kochan, Etah Kurland, Meihua Wang, Carolyn Cho, Sam Rebello. Pharmacokinetic/biomarker (PK/BMx) analysis of the toll-like receptor 7 and 8 (TLR7/8) agonist EIK1001 in phase 1 studies in participants (Pts) with solid tumors [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 7172.

Abstract 4657: PHI-501 is a novel potent next-generation pan-RAF/DDRs inhibitor, and overcomes resistance to RAF or MEK inhibitor in melanoma via dual inhibition of RAF and DDR1/2 signaling

Abstract Background: The prevalent mutation of BRAF (~50%) and NRAS (~30%) in malignant melanomas has led to the aggressive development of RAF and MEK inhibitors as anticancer drugs. However, the major hurdle of targeted therapies for melanoma is resistance to RAF or MEK inhibitors, either intrinsic- or acquired- resistance. PHI-501 is an orally bioavailable and highly effective pan-RAF inhibitor. PHI-501 has dual inhibition activity against pan-RAF and discoidin domain receptor (DDR), a collagen-activated receptor tyrosine kinase. In this study, we evaluated the ability of PHI-501 to overcome drug-resistance to RAF or MEK inhibitors in melanoma harboring NRAS or BRAF mutations. Methods: Three drug-resistant cell lines were established by long-term treatment of belvarafenib in SK-MEL-2 (SK-MEL2BR) and each of dabrafenib and trametinib in SK-MEL-3 (SK-MEL3DR and SK-MEL3TR, respectively). RNA-seq of each resistant cell line and in-depth analysis of sequencing data was conducted, including GSEA. The anti-proliferative activity and signaling inhibition of PHI-501 were evaluated by CCK-8 assay and western blots. A long-term clonogenic assay was performed to confirm cell survival upon PHI-501 treatment. In vivo efficacy was evaluated in SK-MEL-3DR cell line xenograft models. Results: PHI-501 demonstrated significant anti-proliferative effects (GI50 &amp;lt; 1 µM, Mean GI50: 0.3 µM) in all 12 melanoma cell lines tested in this study. PHI-501 exerted cell growth inhibitory activities at least 3 to 50 times stronger than other RAF or MEK inhibitors in each of the resistance cell lines. Moreover, PHI-501 doses of less than 100 nM, significantly inhibited the colony formation of drug-resistant cells. Western blot revealed that PHI-501 retained strong inhibition of both ERK and AKT phosphorylation through downregulating pDDRs. In the SK-MER3DR xenograft mouse model, treatment of PHI-501 alone induced a rapid tumor reduction (TGI 72.1%), whereas the vehicle or dabrafenib did not display an anti-melanoma effect (TGI -7.4%). A comprehensive pathway analysis showed the TNFA-NFKB, IL6-JAK-STAT3, and KRAS signaling enriched in drug-resistant cells compared to the parental cells. PHI-501 treatment effectively downregulated those pathways in all three drug-resistant cells. In particular, PHI-501 downregulates the geneset in epithelial-mesenchymal transition (EMT) signaling more effectively in SK-MEL2BR, SK-MEL3DR, and SK-MEL3TR (Adjusted P=&amp;lt;.0001, and NES: -2.01, -1.72, -2.30, respectively). Conclusion: Novel pan-RAF/DDR dual inhibitor PHI-501 has greater anti-tumor activity in RAF or MEK inhibitor-resistant melanoma, which is through downregulation of MAPK signaling and EMT-related genesets and promoting apoptosis. These data support that the clinical development of PHI-501 for melanoma refractory to MAPK inhibitors. Citation Format: Sue Min Kim, Sungmin Cho, Gi-Jun Sung, Ky-Youb Nam, June Han, Sang Joon Shin. PHI-501 is a novel potent next-generation pan-RAF/DDRs inhibitor, and overcomes resistance to RAF or MEK inhibitor in melanoma via dual inhibition of RAF and DDR1/2 signaling [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 4657.

Improving the performance of LiNi0.8Co0.15Al0.05O2-δ electrode-based fuel cell through cathode modification

LiNi0.8Co0.15Al0.05O2-δ (NCAL) is reported to provide dual catalytic activities of hydroxide reaction (HOR) and oxygen reduction reaction (ORR) in solid oxide fuel cell. However, it has been observed that the performance of NCAL symmetric electrodes undergoes a gradual decrease during fuel cell operation, especially the cathode, which was found to suffer from severe gas diffusion degradation. In this study, we tried to optimize the NCAL cathode by modifying the microstructure in order to increase the cathode performance under extended operation time. During the fabrication of SOFCs, various mass ratios of poly (methyl methacrylate) (PMMA) microspheres were introduced into the NCAL cathode as pore former. The affection of pore former ratio and its size on cell performance is investigated. Results suggest that properly increasing the porosity of the cathode is of significant importance for improving cathode performance, but additionally increasing the porosity of the anode by pore-former is not a wise choice. Besides, considering the oxidation of nickel foam at the cathode, comparative study on the application of nickel foam is carried out to understand its role. In addition, the performance of the cells over a continuous operation for hours has been studied to evaluate the effectiveness of the optimization method. This study provides reference for improving the performance of SOFC based on NCAL electrodes.

Abstract 4455: Metabolic stress induces a double positive feedback loop between AMPK and p62 conferring dual activation of AMPK and NRF2 to synergize antioxidant defense

Abstract Co-occurring mutations in KEAP1 in LKB1-mutant NSCLC activate NRF2 to compensate losing LKB1-AMPK activity during metabolic adaptation and survival. Here, we investigated the regulatory crosstalk between LKB1-AMPK and KEAP1-NRF2 pathways during metabolic stress. We found that metabolic stress activates NRF2 through the expression and phosphorylation of p62, causing the autophagic degradation of KEAP1. Intriguingly, the induction of p62 during metabolic stress is also required to activate AMPK by promoting AXIN-LKB1-AMPK complex formation and recruiting it to the lysosomal membrane. Importantly, the p62-driven dual-activation of AMPK and NRF2 was critical for tumour growth by synergizing antioxidant defences. In turn, the induction of p62 also required LKB1-AMPK activity, suggesting a double positive feedback loop between AMPK and p62. Mechanistically, the increase in lysosomal pH caused by low glucose metabolism and AMPK-dependent reduction of proton generation induced PP2A-dependent dephosphorylation of TFEB/TFE3 which increased the expression of p62. The increase of ROS caused by metabolic stress induced lysosomal MCOLN1-Ca2+ dependent activation of TAK1 which increased p62 phosphorylation. Protons provided by lactic acid abrogated all the effects caused by metabolic stress. This positive feedback loop between AMPK and p62 that activates AMPK and NRF2 can potentially explain why co-occurring mutations in LKB1 and KEAP1 occur and further provide promising therapeutic strategies for lung cancer. Citation Format: Eun-Ji Choi, Hyun-Taek Oh, Seon-Hyeong Lee, Chen-Song Zhang, Mengqi Li, Soo-Youl Kim, Sunghyouk Park, Tong-Shin Chang, Byung-Hoon Lee, Sheng-Cai Lin, Sang-Min Jeon. Metabolic stress induces a double positive feedback loop between AMPK and p62 conferring dual activation of AMPK and NRF2 to synergize antioxidant defense [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 4455.

Abstract 2375: 23ME-01473, a novel anti-ULBP6/2/5 monoclonal antibody, reinvigorates anti-tumor NK cell function through NKG2D and FcγRIIIa activation

Abstract Using genome-wide association studies (GWAS) of the 23andMe genetic and healthy survey database across all phenotypes as part of our unique target discovery platform, we identified immuno-oncology (I/O)-related genetic variants as those with opposing directionality of effects on cancer and immunological phenotypes, which comprise the I/O signature. This I/O signature identified ULBP6 as a potential cancer therapeutic target. ULBP6 is a stress-induced cell surface ligand found on cancer cells, that binds to the activating receptor, NKG2D, on NK and T cells to induce tumor cell killing. However, as a mechanism of immune escape, tumors shed ULBP6 to produce a soluble form that attenuates NKG2D activation and is elevated in cancers. Given that the 2 allelic variants of ULBP6 have the highest binding affinity to NKG2D of all human NKG2D ligands, ULBP6 may be the most immunosuppressive soluble NKG2D ligand and a critical regulator of anti-tumor response. Accordingly, soluble ULBP6 exhibited significant suppression of IFNγ release and detectable cell surface NKG2D expression on healthy donor PBMCs using in vitro cell-based assays. Moreover, the overexpression of human ULBP6 in a genetically modified MC38 murine model resulted in decreased infiltration of NK, NKT, and CD8 T cells in vivo. As such, we developed a novel humanized monoclonal antibody, 23ME-01473, that binds with high affinity to ULBP6, and due to the high sequence homology, to ULBP2 and ULBP5, to block their interaction with NKG2D. By preventing the binding of soluble ULBP6 to NKG2D on PBMCs in vitro, 23ME-01473 restored NKG2D activation as measured by increased detectable cell surface NKG2D expression, IFNγ and granzyme B release, and tumor cell killing by PBMCs. To further leverage the binding of 23ME-01473 to ULBP6/2/5, 23ME-01473 was designed to have an afucosylated Fc domain that enhances its binding affinity to the activating Fc receptor, FcγRIIIa, on NK cells to induce ADCC against tumor cells. The combination of NKG2D and FcγRIIIa activation resulted in synergistic PBMC-mediated IFNγ secretion and enhanced tumor cell killing, compared to activation of either NKG2D or FcγRIIIa. Taken together, these results reveal ULBP6 as a novel cancer therapeutic target, and given the dual activation of NKG2D and FcγRIIIa, suggest the potential of 23ME-01473 to activate NK cells and elicit anti-tumor immunity. Citation Format: Joel Benjamin, Abigail Jarret, Shashank Bharill, Shruti Yadav, Dina Ayupova, Clifford Hom, Zahra Bahrami Dizicheh, I-Ling Chen, Anh Diep, Shi Shi, Caroline Bonnans, Danielle Kellar, Germaine Fuh, Maike Schmidt, Kimberline Gerrick, Patrick Koenig, Mauro Poggio. 23ME-01473, a novel anti-ULBP6/2/5 monoclonal antibody, reinvigorates anti-tumor NK cell function through NKG2D and FcγRIIIa activation [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 2375.

Broad-spectrum nano-bactericide utilizing antimicrobial peptides and bimetallic Cu-Ag nanoparticles anchored onto multiwalled carbon nanotubes for sustained protection against persistent bacterial pathogens in crops

Worldwide crop yields are threatened by persistent pathogenic bacteria that cause significant damage and jeopardize global food security. Chemical pesticides have shown limited effectiveness in protecting crops from severe yield loss. To address this obstacle, there is a growing need to develop environmentally friendly bactericides with broad-spectrum and sustained protection against persistent crop pathogens. Here, we present a method for preparing a nanocomposite that combines antimicrobial peptides (AMPs) and bimetallic Cu-Ag nanoparticles anchored onto multiwalled carbon nanotubes (MWCNTs). The nanocomposite exhibited dual antibacterial activity by disrupting bacterial cell membranes and splicing nucleic acids. By functionalizing MWCNTs with small AMPs (sAMPs), we achieved enhanced stability and penetration of the nanocomposite, and improved loading capacity of the Cu-Ag nanoparticles. The synthesized MWCNTs&CuNCs@AgNPs@P nanocomposites demonstrated broad-spectrum lethality against both Gram-positive and Gram-negative bacterial pathogens. Glasshouse pot trials confirmed the efficacy of the nanocomposites in protecting rice crops against bacterial leaf blight and tomato crops against bacterial wilt. These findings highlight the excellent antibacterial properties of the MWCNTs&CuNCs@AgNPs@P nanocomposite and its potential to replace chemical pesticides, offering significant advantages for agricultural applications.

Piezo-photodynamic therapy of Au@PEG-ZnO nanostructures enabled with a battery-free wireless cancer therapeutic dot

Cancer remains a global health concern, necessitating advanced therapeutic strategies to address its fatal challenges. Conventional treatments, such as radiotherapy and chemotherapy, often lack tumor specificity and may induce systemic toxicity. Photodynamic therapy (PDT) and sonodynamic therapy (SDT) have emerged as promising alternatives, demonstrating high specificity and minimal side effects. In this study, we propose a novel piezo-photodynamic therapy (PPDT) enabled with battery-free wireless cancer therapeutic dot, in which the nanocomposites of gold nanoparticles (Au NPs), zinc oxide nanorods (ZnO NRs) and hydrophilic polyethylene glycol (PEG) can enhance reactive oxygen species (ROS) generation and effectively inhibit tumor growth. The therapeutic dot is implanted directly inside the tissue around the tumor and wirelessly controlled by ultrasound (US), allowing dual activation of electron-hole pairs from the nanocomposites via US and ultraviolet light (UV). The internally generated piezoelectric field minimizes electron-hole recombination, maximizing ROS induction within tumor cells. This PPDT approach surpasses the efficacy of conventional PDT and SDT, showcasing a synergistic therapeutic effect. The study further elucidates the detailed mechanism of Au@PEG-ZnO NRs catalysts, providing insights into their piezoelectric-photocatalytic action. The battery-free wireless control and minimally invasive implantation of the therapeutic dot with inorganic piezo-photocatalyst open new perspectives in cancer therapy.

Platinum Nanoparticles Regulated V2C MXene Nanoplatforms with NIR-II Enhanced Nanozyme Effect for Photothermal and Chemodynamic Anti-Infective Therapy.

Given the challenge of multidrug resistance in antibiotics, non-antibiotic-dependent antibacterial strategies show promise for anti-infective therapy. V2C MXene-based nanomaterials have demonstrated strong biocompatibility and photothermal conversion efficiency (PCE) for photothermal therapy (PTT). However, the limitation of V2C MXene's laser irradiation to the near-infrared region I (NIR-I) restricts tissue penetration, making it difficult to achieve complete bacterial eradication with single-effect therapeutic strategies. To address this, Pt nanoparticles (Pt NPs) are attached to V2C, forming artificial nanoplatforms (Pt@V2C). Pt@V2C exhibits enhanced PCE (59.6%) and a longer irradiation laser (NIR-II) due to the surface plasmon resonance effect of Pt NPs and V2C. Notably, Pt@V2C displays dual enzyme-like activity with chemodynamic therapy (CDT) and NIR-II enhanced dual enzyme-like activity. The biocatalytic mechanism of Pt@V2C is elucidated using density functional theory. In an in vivo animal model, Pt@V2C effectively eliminates methicillin-resistant Staphylococcus aureus from deep-seated tissues in subcutaneous abscesses and bacterial keratitis environments, accelerating abscess resolution and promoting wound and cornea healing through the synergistic effects of PTT/CDT. Transcriptomic analysis reveals that Pt@V2C targets inflammatory pathways, providing insight into its therapeutic mechanism. This study presents a promising therapeutic approach involving hyperthermia-amplified biocatalysis with Pt NPs and MXene nanocomposites.

Mechanism of GTPase activation of a prokaryotic small Ras-like GTPase MglA by an asymmetrically interacting MglB dimer

Cell polarity oscillations in Myxococcus xanthus motility are driven by a prokaryotic small Ras-like GTPase, MglA, which switches from one cell pole to the other in response to extracellular signals. MglA dynamics is regulated by MglB, which functions both as a GAP (GTPase activating protein) and a GEF (guanine nucleotide exchange factor) for MglA. With an aim to dissect the asymmetric role of the two MglB protomers in the dual GAP and GEF activities, we generated a functional MglAB complex by co-expressing MglB with a linked construct of MglA and MglB. This strategy enabled us to generate mutations of individual MglB protomers (MglB1 or MglB2 linked to MglA) and delineate their role in GEF and GAP activities. We establish that the C-terminal helix of MglB1, but not MglB2, stimulates nucleotide exchange through a site away from the nucleotide-binding pocket, confirming an allosteric mechanism. Interaction between the N-terminal β-strand of MglB1 and β0 of MglA is essential for the optimal GEF activity of MglB. Specific residues of MglB2, which interact with Switch-I of MglA, partially contribute to its GAP activity. Thus, the role of the MglB2 protomer in the GAP activity of MglB is limited to restricting the conformation of MglA active site loops. The direct demonstration of the allosteric mechanism of GEF action provides us new insights into the regulation of small Ras-like GTPases, a feature potentially present in many uncharacterized GEFs.

High-performance oxygen evolution reaction via self-optimizing interface engineering with simultaneous activation of dual-sites of surface oxyhydroxides

Metal oxyhydroxides produced by the surface reconstruction were widely considered as active catalytic species in the oxygen evolution reaction (OER). However, simultaneous activation of metal sites in surface oxyhydroxides remains a great challenge. In this study, the interface self-activation strategy was utilized to simultaneously activate both the iron and nickel sites at the surface oxyhydroxides of (Fe,Ni)OOH-NiSe2 nano heterostructure. The OER activity was greatly boosted by the dual activation of active sites, resulting in an overpotential of 245 mV@100 mA cm−2 with a small Tafel slope of 44 mV dec−1. The finely constructed FeOOH-NiSe2 heterostructure was transformed into (Fe,Ni)OOH-NiSe2 through the formation of distinct bonds of M(Fe,Ni)-O-Se during the OER process, which was discovered through a combination of experimental studies with DFT calculations. A fast OER reaction dynamic was achieved due to the unique self-optimized interface structure which produced a dual synergistic effect between the interface structure and the active sites of Fe and Ni of oxyhydroxides, modulated the electronic structure and d band center of active sites, and increased the number of optimum active sites. This work paves a way to design high-performance electrocatalysts with multiple active sites for other electrochemical reactions.

Tougher Bioadhesives through Dual Stimulation Strategies.

Carbene-based bioadhesives have favourable attributes for tissue adhesion, including non-specific bonding to wet and dry tissues, but suffer from relatively weak fracture strength after photocuring. Light irradiation of carbene-precursor (diazirine) also creates inert side products that are absent under thermal activation. Herein, a dual activation method combines light irradiation at elevated temperatures for the evaluation of diazirine depletion and effects on cohesive properties. A customized photo/thermal-rheometer evaluates viscoelastic properties, correlated to the kinetics of carbene:diazoalkane ratios via 19F NMR). The latter exploits the sensitive -CF3 functional group to determine joule-based light/temperature kinetics on trifluoroaryl diazirine consumption. The combination of heat and photoactivation produced bioadhesives that are 3× tougher compared to control. Dual thermal/light irradiation may be a strategy to improve viscoelastic dissipation and toughness of photo-activated adhesive resins.

Functional Characterization of Endo- and Exo-Hydrolase Genes in Arabinan Degradation Gene Cluster of Bifidobacterium longum subsp. suis.

Bifidobacteria are probiotic microorganisms commonly found in the gastrointestinal tract, some of which are known to utilize linear arabino-oligosaccharides (AOS) as prebiotic carbohydrates. In general, the synergistic actions of exo-type α-l-arabinofuranosidases (ABFs) and endo-α-1,5-l-arabinanases (ABNs) are required for efficient arabinan degradation. In this study, the putative gene cluster for arabinan degradation was discovered in the genome of Bifidobacterium longum subsp. suis. It consists of a variety of genes encoding exo- and endo-hydrolases, sugar-binding proteins, ABC-binding cassettes, and transcriptional regulators. Among them, two endo-ABNs GH43 (BflsABN43A and BflsABN43B), two exo-ABFs GH43 (BflsABF43A and BflsABF43B), and an exo-ABF GH51 (BflsABF51) were predicted to be the key hydrolases for arabinan degradation. These hydrolase genes were functionally expressed in Escherichia coli, and their enzymatic properties were characterized. Their synergism in arabinan degradation has been proposed from the detailed modes of action. Extracellular endo-BflsABN43A hydrolyzes sugar beet and debranched arabinans into the short-chain branched and linear AOS. Intracellularly, AOS can be further degraded into l-arabinose via the cooperative actions of endo-BflsABN43B, exo-BflsABF43A with debranching activity, α-1,5-linkage-specific exo-BflsABF43B, and exo-BflsABF51 with dual activities. The resulting l-arabinose is expected to be metabolized into energy through the pentose phosphate pathway by three enzymes expressed from the ara operon of bifidobacteria. It is anticipated that uncovering arabinan utilization gene clusters and their detailed functions in the genomes of diverse microorganisms will facilitate the development of customized synbiotics.

CD73/adenosine axis exerts cardioprotection against hypobaric hypoxia-induced metabolic shift and myocarditis in a sex-dependent manner

BackgroundClinical and experimental studies have shown that the myocardial inflammatory response during pathological events varies between males and females. However, the cellular and molecular mechanisms of these sex differences remain elusive. CD73/adenosine axis has been linked to anti-inflammatory responses, but its sex-specific cardioprotective role is unclear. The present study aimed to investigate whether the CD73/adenosine axis elicits sex-dependent cardioprotection during metabolic changes and myocarditis induced by hypobaric hypoxia.MethodsFor 7 days, male and female mice received daily injections of the CD73 inhibitor adenosine 5′- (α, β-methylene) diphosphate (APCP) 10 mg/kg/day while they were kept under normobaric normoxic and hypobaric hypoxic conditions. We evaluated the effects of hypobaric hypoxia on the CD73/adenosine axis, myocardial hypertrophy, and cardiac electrical activity and function. In addition, metabolic homeostasis and immunoregulation were investigated to clarify the sex-dependent cardioprotection of the CD73/adenosine axis.ResultsHypobaric hypoxia-induced cardiac dysfunction and adverse remodeling were more pronounced in male mice. Also, male mice had hyperactivity of the CD73/adenosine axis, which aggravated myocarditis and metabolic shift compared to female mice. In addition, CD73 inhibition triggered prostatic acid phosphatase ectonucleotidase enzymatic activity to sustain adenosine overproduction in male mice but not in female mice. Moreover, dual inhibition prostatic acid phosphatase and CD73 enzymatic activities in male mice moderated adenosine content, alleviating glycolytic shift and proinflammatory response.ConclusionThe CD73/adenosine axis confers a sex-dependent cardioprotection. In addition, extracellular adenosine production in the hearts of male mice is influenced by prostatic acid phosphatase and tissue nonspecific alkaline phosphatase.