Network pharmacology study and in vitro experimental validation of Xiaojianzhong decoction against gastric cancer.

BACKGROUND: Cancer is one of the most serious threats to human health worldwide. Conventional treatments such as surgery and chemotherapy are associated with some drawbacks. In recent years, traditional Chinese medicine treatment has been increasingly advocated by patients and attracted attention from clinicians, and has become an indispensable part of the comprehensive treatment for gastric cancer. AIM: To investigate the mechanism of Xiaojianzhong decoction (XJZ) in the treatment of gastric cancer (GC) by utilizing network pharmacology and experimental validation, so as to provide a theoretical basis for later experimental research. METHODS: We analyzed the mechanism and targets of XJZ in the treatment of GC through network pharmacology and bioinformatics. Subsequently, we verified the impact of XJZ treatment on the proliferative ability of GC cells through CCK-8, apoptosis, cell cycle, and clone formation assays. Additionally, we performed Western blot analysis and real-time quantitative PCR to assess the protein and mRNA expression of the core proteins. RESULTS: XJZ mainly regulates IL6, PTGS2, CCL2, MMP9, MMP2, HMOX1, and other target genes and pathways in cancer to treat GC. The inhibition of cell viability, the increase of apoptosis, the blockage of the cell cycle at the G0/G1 phase, and the inhibition of the ability of cell clone formation were observed in AGS and HGC-27 cells after XJZ treatment. In addition, XJZ induced a decrease in the mRNA expression of IL6, PTGS2, MMP9, MMP2, and CCL2, and an increase in the mRNA expression of HOMX1. XJZ significantly inhibited the expression of IL6, PTGS2, MMP9, MMP2, and CCL2 proteins and promoted the expression of the heme oxygenase-1 protein. CONCLUSION: XJZ exerts therapeutic effects against GC through multiple components, multiple targets, and multiple pathways. Our findings provide a new idea and scientific basis for further research on the molecular mechanisms underlying the therapeutic effects of XJZ in the treatment of GC.

Phototherapeutic applications of benzophenone-containing NIR-emitting photosensitizers based on different receptor modulations.

Photodynamic therapy (PDT) plays a crucial role in treating cancer and major infectious diseases. However, the hypoxic microenvironment and deep-seated tumors often compromise the effectiveness of photosensitizers (PSs). PSs primarily generate type-II reactive oxygen species (ROS), which are limited under hypoxic conditions. Pyridinium salts frequently exhibit critical dark toxicity in vitro. Moreover, PDT alone often fails to achieve optimal anti-tumor effects compared to its combined application with photothermal therapy (PTT). To address these issues, we replaced pyridinium with quinolinium, significantly reducing dark toxicity. Additionally, the incorporation of benzophenone enhanced ROS generation, achieving a synergistic effect of type-I and type-II PDT. Fine-tuning the conjugated structure enhanced the donor-acceptor (D-A) intensity, while the stretching vibrations of carbon-carbon double bonds and carbon-nitrogen triple bonds red-shifted the excitation wavelength to the near-infrared (NIR) region and improved the photothermal conversion efficiency (PCE). This strategy provides a molecular design approach for achieving synergy between PDT and PTT. The synthesized four NIR-emitting aggregation-induced emission quinolinium salts exhibited mitochondrial targeting ability and low dark toxicity. Among them, FCN-TPAQ-BP showed excellent ROS generation capability, a PCE of 39.2%, good biocompatibility, and low dark toxicity, making it an ideal candidate for enhancing PDT's antitumor efficacy.

Molecular mechanism of Saikosaponin-d in the treatment of gastric cancer based on network pharmacology and in vitro experimental verification.

The study aimed to utilize network pharmacology combined with cell experiments to research the mechanism of action of Saikosaponin-d in the treatment of gastric cancer. Drug target genes were obtained from the PubChem database and the Swiss Target Prediction database. Additionally, target genes for gastric cancer were obtained from the GEO database and the Gene Cards database. The core targets were then identified and further analyzed through gene ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), and GESA enrichment. The clinical relevance of the core targets was assessed using the GEPIA and HPA databases. Molecular docking of drug monomers and core target proteins was performed using Auto Duck Tools and Pymol software. Finally, in vitro cellular experiments including cell viability, apoptosis, cell scratch, transwell invasion, transwell migration, qRT-PCR, and Western blot were conducted to verify these findings of network pharmacology. The network pharmacology analysis predicted that the drug monomers interacted with 54 disease targets. Based on clinical relevance analysis, six core targets were selected: VEGFA, IL2, CASP3, BCL2L1, MMP2, and MMP1. Molecular docking results showed binding activity between the Saikosaponin-d monomer and these core targets. Saikosaponin-d could inhibit gastric cancer cell proliferation, induce apoptosis, and inhibit cell migration and invasion.

RNF216 Inhibits the Replication of H5N1 Avian Influenza Virus and Regulates the RIG-I Signaling Pathway in Ducks.

The RING finger (RNF) family, a group of E3 ubiquitin ligases, plays multiple essential roles in the regulation of innate immunity and resistance to viral infection in mammals. However, it is still unclear whether RNF proteins affect the production of IFN-I and the replication of avian influenza virus (AIV) in ducks. In this article, we found that duck RNF216 (duRNF216) inhibited the duRIG-I signaling pathway. Conversely, duRNF216 deficiency enhanced innate immune responses in duck embryonic fibroblasts. duRNF216 did not interacted with duRIG-I, duMDA5, duMAVS, duSTING, duTBK1, or duIRF7 in the duck RIG-I pathway. However, duRNF216 targeted duTRAF3 and inhibited duMAVS in the recruitment of duTRAF3 in a dose-dependent manner. duRNF216 catalyzed K48-linked polyubiquitination of duck TRAF3, which was degraded by the proteasome pathway. Additionally, AIV PB1 protein competed with duTRAF3 for binding to duRNF216 to reduce degradation of TRAF3 by proteasomes in the cytoplasm, thereby slightly weakening duRNF216-mediated downregulation of IFN-I. Moreover, although duRNF216 downregulated the IFN-ß expression during virus infection, the expression level of IFN-ß in AIV-infected duck embryonic fibroblasts overexpressing duRNF216 was still higher than that in uninfected cells, which would hinder the viral replication. During AIV infection, duRNF216 protein targeted the core protein PB1 of viral polymerase to hinder viral polymerase activity and viral RNA synthesis in the nucleus, ultimately strongly restricting viral replication. Thus, our study reveals a new mechanism by which duRNF216 downregulates innate immunity and inhibits AIV replication in ducks. These findings broaden our understanding of the mechanisms by which the duRNF216 protein affects AIV replication in ducks.

Hawthorn with "homology of medicine and food": a review of anticancer effects and mechanisms.

Over the past few years, there has been a gradual increase in the incidence of cancer, affecting individuals at younger ages. With its refractory nature and substantial fatality rate, cancer presents a notable peril to human existence and wellbeing. Hawthorn, a medicinal food homology plant belonging to the Crataegus genus in the Rosaceae family, holds great value in various applications. Due to its long history of medicinal use, notable effects, and high safety profile, hawthorn has garnered considerable attention and plays a crucial role in cancer treatment. Through the integration of modern network pharmacology technology and traditional Chinese medicine (TCM), a range of anticancer active ingredients in hawthorn have been predicted, identified, and analyzed. Studies have shown that ingredients such as vitexin, isoorientin, ursolic acid, and maslinic acid, along with hawthorn extracts, can effectively modulate cancer-related signaling pathways and manifest anticancer properties via diverse mechanisms. This review employs network pharmacology to excavate the potential anticancer properties of hawthorn. By systematically integrating literature across databases such as PubMed and CNKI, the review explores the bioactive ingredients with anticancer effects, underlying mechanisms and pathways, the synergistic effects of drug combinations, advancements in novel drug delivery systems, and ongoing clinical trials concerning hawthorn's anticancer properties. Furthermore, the review highlights the preventive health benefits of hawthorn in cancer prevention, offering valuable insights for clinical cancer treatment and the development of TCM with anticancer properties that can be used for both medicinal and edible purposes.

The Role and Mechanism of Paeoniae Radix Alba in Tumor Therapy.

Tumors have a huge impact on human life and are now the main cause of disease-related deaths. The main means of treatment are surgery and radiotherapy, but they are more damaging to the organism and have a poor postoperative prognosis. Therefore, we urgently need safe and effective drugs to treat tumors. In recent years, Chinese herbal medicines have been widely used in tumor therapy as complementary and alternative therapies. Medicinal and edible herbs are popular and have become a hot topic of research, which not only have excellent pharmacological effects and activities, but also have almost no side effects. Therefore, as a typical medicine and food homology, some components of Paeoniae Radix Alba (PRA, called Baishao in China) have been shown to have good efficacy and safety against cancer. Numerous studies have also shown that Paeoniae Radix Alba and its active ingredients treat cancer through various pathways and are also one of the important components of many antitumor herbal compound formulas. In this paper, we reviewed the literature on the intervention of Paeoniae Radix Alba in tumors and its mechanism of action in recent years and found that there is a large amount of literature on its effect on total glucosides of paeony (TGP) and paeoniflorin (PF), as well as an in-depth discussion of the mechanism of action of Paeoniae Radix Alba and its main constituents, with a view to promote the clinical development and application of Paeoniae Radix Alba in the field of antitumor management.

A validated LC-MS/MS method for the quantitation of daratumumab in rat serum using rapid tryptic digestion without IgG purification and reduction.

Daratumumab, a humanized monoclonal antibody utilized in treating immunoglobulin light-chain amyloidosis and relapsed/refractory multiple myeloma, was quantified in rat serum through a simple, economical and effective liquid chromatography tandem-mass spectrometry (LC-MS/MS) method. A surrogate peptide, LLIYDASNR, derived from trypsin hydrolysis, was quantitatively analyzed with LLIYDASN [13C6, 15N4] RAT as an internal standard. This corrected variations from sample pretreatment and mass spectrometry response, involving denaturation and trypsin hydrolysis in a two-step process lasting approximately 1 hour. Methodological validation demonstrated a linear range of 1 µg/mL to 1000 µg/mL in rat serum. Precision, accuracy, matrix effect, sensitivity, stability, selectivity, carryover, and interference met acceptance criteria. The validated LC-MS/MS approach was successfully applied to a pharmacokinetic study of daratumumab in rats at an intravenous dose of 15 mg/kg.

Precise molecular engineering for the preparation of pyridinium photosensitizers with efficient ROS generation and photothermal conversion.

Organic photosensitizers (PSs) with aggregation-induced emission properties have great development potential in the integrated application of multi-mode diagnosis and treatment of photodynamic therapy (PDT) and photothermal therapy (PTT). However, preparing high-quality PSs with both optical and biological properties, high reactive oxygen species (ROS) and photothermal conversion ability are undoubtedly a great challenge. In this work, a series of pyridinium AIE PSs modified with benzophenone have been synthesized. A wide wavelength range of fluorescent materials was obtained by changing the conjugation and donor-acceptor strength. TPAPs5 has a significant advantage over similar compounds, and we have also identified the causes of high ROS generation and high photothermal conversion in terms of natural transition orbitals, excited state energy levels, ground-excited state configuration differences and recombination energy. Interestingly, migration of target sites was also found in biological imaging experiments, which also provided ideas for the design of double-targeted fluorescent probes. Therefore, the present work proposed an effective molecular design strategy for synergistic PDT and PTT therapy.

Generation of Functional and Mature Sympathetic Neurons from Human Pluripotent Stem Cells via a Neuroepithelial Route.

The sympathetic nervous system (SNS) is a crucial branch of the autonomic nervous system (ANS) that is responsible for regulating visceral function and various physiological processes. Dysfunction of the SNS can lead to various diseases, such as hypertension and metabolic disorders. However, obtaining sympathetic neurons from human tissues for research is challenging. The current research aimed at recapitulating the process of human sympathetic neuron development and achieved the successful establishment of a stepwise, highly efficient in vitro differentiation protocol. This protocol facilitated the generation of functional and mature sympathetic neurons from human pluripotent stem cells (hPSCs) using a chemical-defined induction medium. Initially, each differentiation stage was refined to derive sympathoadrenal progenitors (SAPs) from hPSCs through neural epithelial cells (NECs) and trunk neural crest stem cells (NCSCs). hPSC-derived SAPs could be expanded in vitro for at least 12 passages while maintaining the expression of SAP-specific transcription factors and neuronal differentiation potency. SAPs readily generated functional sympathetic neurons (SymNs) when cultured in the neuronal maturation medium for 3-4 weeks. These SymNs expressed sympathetic markers, exhibited electrophysiological properties, and secreted sympathetic neurotransmitters. More importantly, we further demonstrated that hPSC-derived SymNs can efficiently regulate the adipogenesis of human adipose-derived stem cells (ADSCs) and lipid metabolism in vitro. In conclusion, our study provided a simple and robust protocol for generating functional sympathetic neurons from hPSCs, which may be an invaluable tool in unraveling the mechanisms of SNS-related diseases.

Discovery of Pyrido[2,3-d]pyrimidin-7-one Derivatives as Highly Potent and Efficacious Ectonucleotide Pyrophosphatase/Phosphodiesterase 1 (ENPP1) Inhibitors for Cancer Treatment.

Ectonucleotide pyrophosphatase/phosphodiesterase 1 (ENPP1) is an extracellular enzyme responsible for hydrolyzing cyclic guanosine monophosphate-adenosine monophosphate (cGAMP), the endogenous agonist for the stimulator of interferon genes (STING) pathway. Inhibition of ENPP1 can trigger STING and promote antitumor immunity, offering an attractive therapeutic target for cancer immunotherapy. Despite progress in the discovery of ENPP1 inhibitors, the diversity in chemical structures and the efficacy of the agents are far from desirable, emphasizing the demand for novel inhibitors. Herein, we describe the design, synthesis, and biological evaluation of a series of ENPP1 inhibitors based on the pyrido[2,3-d]pyrimidin-7-one scaffold. Optimization efforts led to compound 31 with significant potency in both ENPP1 inhibition and STING pathway stimulation in vitro. Notably, 31 demonstrated in vivo efficacy in a syngeneic 4T1 mouse triple negative breast cancer model. These findings provide a promising lead compound with a novel scaffold for further drug development in cancer immunotherapy.

Investigation on the mechanism of the combination of eremias multiocellata and cisplatin in reducing chemoresistance of gastric cancer based on in vitro and in vivo experiments.

BACKGROUND: Cisplatin (DDP) is one of the important chemotherapy drugs for patients with advanced gastric cancer and metastasis, but its resistance is a bottleneck problem that affects clinical efficacy and patient survival. Eremias multiocellata (EM) is a traditional Chinese herbal medicine, which has been used in the treatment of precancerous lesions, gastric cancer, liver fibrosis, and other digestive diseases. However, the mechanism of reducing chemotherapy resistance to gastric cancer is still unclear. METHODS: We used the MTT assay to evaluate the proliferative viability of gastric cancer parental cell line MKN45 and its drug-resistant cell line MKN45/DDP, and compared their drug-resistance indices. The migration and invasion abilities of MKN45/DDP drug-resistant cells were evaluated using the Transwell assay. Apoptosis in MKN45/DDP drug-resistant cells was detected using flow cytometry. The effect of a combination of EM and cisplatin on the levels of reactive oxygen species (ROS) and lipid peroxides (LPO) in cisplatin-resistant gastric cancer cells was detected using ROS fluorescent probes and a lipid peroxidation assay kit in conjunction with flow cytometry. The effect of EM combined with cisplatin on the level of iron ions was detected by fluorescence probe and confocal laser technique. Hematoxylin-eosin staining (HE staining) was used to detect the histopathologic morphology of drug-resistant gastric cancer in nude mice. Ferroptosis-related proteins were measured using immunohistochemistry. Real-time fluorescence quantitative polymerase chain reaction (RT-qPCR) was used to detect tumor drug resistance-related genes. The NF-κB/Snail pathway-related proteins, PI3K/AKT/mTOR pathway-related proteins, and drug resistance-related proteins were detected by Western blot. RESULTS AND CONCLUSIONS: The results of in vitro and in vivo experiments showed that EM combined with DDP could effectively inhibit the migration and invasive ability of MKN45/DDP cells, as well as induce apoptosis of MKN45/DDP cells; the combination of the two drugs could significantly increase the levels of ROS, lipid peroxidation and divalent ferric ions in MKN45/DDP cells, at the same time reducing the levels of Ferroptosis-related proteins, which could induce Ferroptosis. In addition, EM combined with DDP can also exert the effect of reversing DDP resistance and increasing the sensitivity of gastric cancer drug-resistant cells to DDP by regulating the NF-κB/Snail signaling pathway, PI3K/AKT/mTOR signaling pathway, and the expression of drug resistance-related proteins and genes.

A robust and validated LC-MS/MS method for the quantification of ramucirumab in rat and human serum using direct enzymatic digestion without immunoassay.

A new liquid chromatography tandem mass spectrometry (LC-MS/MS) method was established to quantify the anti-gastric cancer fully human monoclonal antibody (ramucirumab) in rat and human serum. The surrogate peptide (GPSVLPLAPSSK) for ramucirumab was generated by trypsin hydrolysis and quantified using the isotopically labeled peptide GPSVLPLAPSSK[13C6, 15N2]ST containing two more amino acids at the carboxyl end as an internal standard to correct for variations introduced during the enzymatic hydrolysis process and any mass spectrometry changes. Additionally, the oxidation and deamidation of unstable peptides (VVSVLTVLHQDWLNGK and NSLYLQMNSLR) were detected. The quantitative range of the proposed method was 1-1000 µg/mL, and complete methodological validation was performed. The precision, accuracy, matrix effect, sensitivity, stability, selectivity, carryover, and interference of the measurements met the required standards. The validated LC-MS/MS method was applied to pharmacokinetic studies in rats administered ramucirumab at 15 mg/kg intravenously. Overall, a robust, efficient, and cost-effective LC-MS/MS method was successfully developed for quantifying ramucirumab in rat and human serum.

Efficient Treatment of Pulpitis via Transplantation of Human Pluripotent Stem Cell-Derived Pericytes Partially through LTBP1-Mediated T Cell Suppression.

Dental pulp pericytes are reported to have the capacity to generate odontoblasts and express multiple cytokines and chemokines that regulate the local immune microenvironment, thus participating in the repair of dental pulp injury in vivo. However, it has not yet been reported whether the transplantation of exogenous pericytes can effectively treat pulpitis, and the underlying molecular mechanism remains unknown. In this study, using a lineage-tracing mouse model, we showed that most dental pulp pericytes are derived from cranial neural crest. Then, we demonstrated that the ablation of pericytes could induce a pulpitis-like phenotype in uninfected dental pulp in mice, and we showed that the significant loss of pericytes occurs during pupal inflammation, implying that the transplantation of pericytes may help to restore dental pulp homeostasis during pulpitis. Subsequently, we successfully generated pericytes with immunomodulatory activity from human pluripotent stem cells through the intermediate stage of the cranial neural crest with a high level of efficiency. Most strikingly, for the first time we showed that, compared with the untreated pulpitis group, the transplantation of hPSC-derived pericytes could substantially inhibit vascular permeability (the extravascular deposition of fibrinogen, ** p < 0.01), alleviate pulpal inflammation (TCR+ cell infiltration, * p < 0.05), and promote the regeneration of dentin (** p < 0.01) in the mouse model of pulpitis. In addition, we discovered that the knockdown of latent transforming growth factor beta binding protein 1 (LTBP1) remarkably suppressed the immunoregulation ability of pericytes in vitro and compromised their in vivo regenerative potential in pulpitis. These results indicate that the transplantation of pericytes could efficiently rescue the aberrant phenotype of pulpal inflammation, which may be partially due to LTBP1-mediated T cell suppression.

Combined inhibition of surface CD51 and γ-secretase-mediated CD51 cleavage improves therapeutic efficacy in experimental metastatic hepatocellular carcinoma.

BACKGROUND & AIMS: Integrin αv (ITGAV, CD51) is regarded as a key component in multiple stages of tumor progression. However, the clinical failure of cilengitide, a specific inhibitor targeting surface CD51, suggests the importance of yet-unknown mechanisms by which CD51 promotes tumor progression. METHODS: In this study, we used several hepatocellular carcinoma (HCC) cell lines and murine hepatoma cell lines. To investigate the role of CD51 on HCC progression, we used a 3D invasion assay and in vivo bioluminescence imaging. We used periostin-knockout transgenic mice to uncover the role of the tumor microenvironment on CD51 cleavage. Moreover, we used several clinically relevant HCC models, including patient-derived organoids and patient-derived xenografts, to evaluate the therapeutic efficacy of cilengitide in combination with the γ-secretase inhibitor LY3039478. RESULTS: We found that CD51 could undergo transmembrane cleavage by γ-secretase to produce a functional intracellular domain (CD51-ICD). The cleaved CD51-ICD facilitated HCC invasion and metastasis by promoting the transcription of oxidative phosphorylation-related genes. Furthermore, we identified cancer-associated fibroblast-derived periostin as the major driver of CD51 cleavage. Lastly, we showed that cilengitide-based therapy led to a dramatic therapeutic effect when supplemented with LY3039478 in both patient-derived organoid and xenograft models. CONCLUSIONS: In summary, we revealed previously unrecognized mechanisms by which CD51 is involved in HCC progression and uncovered the underlying cause of cilengitide treatment failure, as well as providing evidence supporting the translational prospects of combined CD51-targeted therapy in the clinic. IMPACT AND IMPLICATIONS: Integrin αv (CD51) is a widely recognized pro-tumoral molecule that plays a crucial role in various stages of tumor progression, making it a promising therapeutic target. However, despite early promising results, cilengitide, a specific antagonist of CD51, failed in a phase III clinical trial. This prompted further investigation into the underlying mechanisms of CD51's effects. This study reveals that the γ-secretase complex directly cleaves CD51 to produce an intracellular domain (CD51-ICD), which functions as a pro-tumoral transcriptional regulator and can bypass the inhibitory effects of cilengitide by entering the nucleus. Furthermore, the localization of CD51 in the nucleus is significantly associated with the prognosis of patients with HCC. These findings provide a theoretical basis for re-evaluating cilengitide in clinical settings and highlight the importance of identifying a more precise patient subpopulation for future clinical trials targeting CD51.

Cadmium tolerance and hyperaccumulation in plants - A proteomic perspective of phytoremediation.

Cadmium (Cd) is a major environmental pollutant and poses a risk of transfer into the food chain through contaminated plants. Mechanisms underlying Cd tolerance and hyperaccumulation in plants are not fully understood. Proteomics-based approaches facilitate an in-depth understanding of plant responses to Cd stress at the systemic level by identifying Cd-inducible differentially abundant proteins (DAPs). In this review, we summarize studies related to proteomic changes associated with Cd-tolerance mechanisms in Cd-tolerant crops and Cd-hyperaccumulating plants, especially the similarities and differences across plant species. The enhanced DAPs identified through proteomic studies can be potential targets for developing Cd-hyperaccumulators to remediate Cd-contaminated environments and Cd-tolerant crops with low Cd content in the edible organs. This is of great significance for ensuring the food security of an exponentially growing global population. Finally, we discuss the methodological drawbacks in current proteomic studies and propose that better protocols and advanced techniques should be utilized to further strengthen the reliability and applicability of future Cd-stress-related studies in plants. This review provides insights into the improvement of phytoremediation efficiency and an in-depth study of the molecular mechanisms of Cd enrichment in plants.

The role of TNF-α in the fate regulation and functional reprogramming of mesenchymal stem cells in an inflammatory microenvironment.

Mesenchymal stem cells (MSCs) are pluripotent stem cells with multidirectional differentiation potential and strong immunomodulatory capacity. MSCs have been widely used in the treatment of injured, inflammatory, and immune-related diseases. Resting MSCs lack differentiation and immunomodulatory ability. Instead, they rely on microenvironmental factors to: 1) stimulate and regulate their expression of specific cell growth factors, chemokines, immunomodulatory factors, or receptors; or 2) direct their differentiation into specific tissue cells, which ultimately perform tissue regeneration and repair and immunomodulatory functions. Tumor necrosis factor (TNF)-α is central to the creation of an inflammatory microenvironment. TNF-α regulates the fate and functional reprogramming of MSCs, either alone or in combination with a variety of other inflammatory factors. TNF-α can exert opposing effects on MSCs, from inducing MSC apoptosis to enhancing their anti-tumor capacity. In addition, the immunomodulation and osteogenic differentiation capacities of MSCs, as well as their exosome or microvesicle components vary significantly with TNF-α stimulating concentration, time of administration, or its use in combination with or without other factors. Therefore, this review discusses the impact of TNF-α on the fate and functional reprogramming of MSCs in the inflammatory microenvironment, to provide new directions for improving the immunomodulatory and tissue repair functions of MSCs and enhance their therapeutic potential.

Arabidopsis ABCG14 forms a homodimeric transporter for multiple cytokinins and mediates long-distance transport of isopentenyladenine-type cytokinins.

Cytokinins (CKs), primarily trans-zeatin (tZ) and isopentenyladenine (iP) types, play critical roles in plant growth, development, and various stress responses. Long-distance transport of tZ-type CKs meidated by Arabidopsis ATP-binding cassette transporter subfamily G14 (AtABCG14) has been well studied; however, less is known about the biochemical properties of AtABCG14 and its transporter activity toward iP-type CKs. Here we reveal the biochemical properties of AtABCG14 and provide evidence that it is also required for long-distance transport of iP-type CKs. AtABCG14 formed homodimers in human (Homo sapiens) HEK293T, tobacco (Nicotiana tabacum), and Arabidopsis cells. Transporter activity assays of AtABCG14 in Arabidopsis, tobacco, and yeast (Saccharomyces cerevisiae) showed that AtABCG14 may directly transport multiple CKs, including iP- and tZ-type species. AtABCG14 expression was induced by iP in a tZ-type CK-deficient double mutant (cypDM) of CYP735A1 and CYP735A2. The atabcg14 cypDM triple mutant exhibited stronger CK-deficiency phenotypes than cypDM. Hormone profiling, reciprocal grafting, and 2H6-iP isotope tracer experiments showed that root-to-shoot and shoot-to-root long-distance transport of iP-type CKs were suppressed in atabcg14 cypDM and atabcg14. These results suggest that AtABCG14 participates in three steps of the circular long-distance transport of iP-type CKs: xylem loading in the root for shootward transport, phloem unloading in the shoot for shoot distribution, and phloem unloading in the root for root distribution. We found that AtABCG14 displays transporter activity toward multiple CK species and revealed its versatile roles in circular long-distance transport of iP-type CKs. These findings provide new insights into the transport mechanisms of CKs and other plant hormones.

Karrikin Receptor KAI2 Coordinates Salt Tolerance Mechanisms in Arabidopsis thaliana.

Plants activate a myriad of signaling cascades to tailor adaptive responses under environmental stresses, such as salinity. While the roles of exogenous karrikins (KARs) in salt stress mitigation are well comprehended, genetic evidence of KAR signaling during salinity responses in plants remains unresolved. Here, we explore the functions of the possible KAR receptor KARRIKIN-INSENSITIVE2 (KAI2) in Arabidopsis thaliana tolerance to salt stress by investigating comparative responses of wild-type (WT) and kai2-mutant plants under a gradient of NaCl. Defects in KAI2 functions resulted in delayed and inhibited cotyledon opening in kai2 seeds compared with WT seeds, suggesting that KAI2 played an important role in enhancing seed germination under salinity. Salt-stressed kai2 plants displayed more phenotypic aberrations, biomass reduction, water loss and oxidative damage than WT plants. kai2 shoots accumulated significantly more Na+ and thus had a lower K+/Na+ ratio, than WT, indicating severe ion toxicity in salt-stressed kai2 plants. Accordingly, kai2 plants displayed a lower expression of genes associated with Na+ homeostasis, such as SALT OVERLY SENSITIVE (SOS) 1, SOS2, HIGH-AFFINITY POTASSIUM TRANSPORTER 1;1 (HKT1;1) and CATION-HYDROGEN EXCHANGER 1 (NHX1) than WT plants. WT plants maintained a better glutathione level, glutathione-related redox status and antioxidant enzyme activities relative to kai2 plants, implying KAI2's function in oxidative stress mitigation in response to salinity. kai2 shoots had lower expression levels of genes involved in the biosynthesis of strigolactones (SLs), salicylic acid and jasmonic acid and the signaling of abscisic acid and SLs than those of WT plants, indicating interactive functions of KAI2 signaling with other hormone signaling in modulating plant responses to salinity. Collectively, these results underpin the likely roles of KAI2 in the alleviation of salinity effects in plants by regulating several physiological and biochemical mechanisms involved in ionic and osmotic balance, oxidative stress tolerance and hormonal crosstalk.

Nestin+ Peyer's patch resident MSCs enhance healing of inflammatory bowel disease through IL-22-mediated intestinal epithelial repair.

Inflammatory bowel disease (IBD) is a chronic condition characterized by gastrointestinal tract inflammation and still lacks satisfactory treatments. Mesenchymal stromal cells (MSCs) show promising potential for treating IBD, but their therapeutic efficacy varies depending on the tissue of origin. We aim to investigate whether intestine Peyer's patch (PP)-derived MSCs have superior immunomodulatory effects on T cells and better therapeutic effects on IBD compared with bone marrow-derived MSCs. We isolated PPs-derived Nestin+ MSCs (MSCsPP ) and bone marrow-derived Nestin+ MSCs (MSCsBM ) from Nestin-GFP transgenic mice to explore their curative effects on murine IBD model. Moreover, we tested the effects of IL-22 knockdown and IL-22 overexpression on the therapeutic efficacy of MSCsPP and MSCsBM in murine IBD, respectively. We demonstrated that Nestin+ cells derived from murine PPs exhibit MSC-like biological characteristics. Compared with MSCsBM , MSCsPP possess enhanced immunoregulatory ability to suppress T cell proliferation and inflammatory cytokine production. Moreover, we observed that MSCsPP exhibited greater therapeutic efficacy than MSCsBM in murine IBD models. Interestingly, IL-22, which was highly expressed in MSCsPP , could alleviate the severity of the intestinal inflammation, while knockdown IL-22 of MSCsPP remarkably weakened the therapeutic effects. More importantly, IL-22 overexpressing MSCsBM could significantly improve the symptoms of murine IBD models. This study systemically demonstrated that murine MSCsPP have a prominent advantage in murine IBD treatment, partly through IL-22.