ABSTRACT
In this work, a composite hydrogel material consisting of chitosan-based composite hydrogel was prepared by a simple and rapid synthetic method and will be named three-dimensional (3D)-IL-COF-1@CS hydrogel. Possessing a stable 3D network structure and outstanding hydrophilicity, the novel hydrogel is capable of capturing glycopeptides. The 3D-IL-COF-1@CS hydrogel showed good sensitivity (0.1 fmol/µL) and selectivity (1:2000). In addition, 19 glycopeptides were captured in standard samples. In the analysis of human serum, 148 glycopeptides assigned to 72 glycoproteins were assayed in the serum of normal individuals, and 245 glycopeptides corresponding to 100 glycoproteins were found in the serum of colorectal cancer (CRC) patients. More importantly, several functional programs based on Gene Ontology analysis supported molecular biological processes that may be relevant to the pathogenesis of CRC, including aging, fibrinogen complex, and arylesterase activity. The low cost, simplicity, rapid synthesis, and good enrichment performance have a great future in glycoproteomics analysis and related diseases.
Subject(s)
Colorectal Neoplasms , Glycopeptides , Hydrophobic and Hydrophilic Interactions , Humans , Colorectal Neoplasms/blood , Glycopeptides/blood , Glycopeptides/chemistry , Hydrogels/chemistry , Polymers/chemistry , Chitosan/chemistryABSTRACT
Artificial sweeteners have been widely used as additives in various beverages. Due to the safety risks associated with artificial sweeteners, it is essential to develop a simple, rapid, and high-throughput method for the analysis of artificial sweeteners. Here, we report a homogeneous binary matrix assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) assay for the simultaneous analysis of sweeteners including aspartame (ASP), neotame (NEO), and advantame (ADV) with a simple dilution step. The combination of nanodiamonds with 2,5-dihydroxybenzoic acid effectively improved the signal response of sweeteners, decreased the background noise, and improved the "spot-to-spot" repeatability. After the optimization, the method exhibits low limits of detection (ASP: 20 nΜ; NEO: 10 nΜ; ADV: 5 nΜ), good linearity (r > 0.995), satisfactory accuracy (96.2-103.0%), and lower RSDs (1.5-5.8%). Finally, the target sweeteners in 17 soft beverages were successfully determined with this method, showing the potential for the routine analysis of artificial sweeteners.
ABSTRACT
A dipeptide-based bifunctional material immobilized with Ti4+ (denoted as APE-MBA-VPA-Ti4+) was developed using precipitation polymerization. This polymer combines hydrophilic interaction liquid chromatography (HILIC) and immobilized metal affinity chromatography (IMAC) enrichment strategies, allowing for the individual and simultaneous enrichment of glycopeptides and phosphopeptides. It demonstrated high sensitivity (0.1 fmol µL-1 for glycopeptides, 0.005 fmol µL-1 for phosphopeptides), strong selectivity (molar ratio HRP: BSA = 1:1000, ß-casein: BSA = 1:2500), consistent reusability (10 cycles) and satisfactory recovery rate (93.5 ± 1.8 % for glycopeptides, 91.6 ± 0.6 % for phosphopeptides) in the individual enrichment. Utilizing nano LC-MS/MS technology, the serum of liver cancer patients was analyzed after enrichment individually, resulting in the successful capture of 333 glycopeptides covering 262 glycosylation sites, corresponding to 131 glycoproteins, as well as 67 phosphopeptides covering 57 phosphorylation sites, related to 48 phosphoproteins. In comparison, the serum of normal healthy individuals yielded a total of 283 glycopeptides covering 244 glycosylation sites corresponding to 126 glycoproteins, as well as 66 phosphopeptides covering 56 phosphorylation sites related to 37 phosphoproteins. Label-free quantification identified 10 differentially expressed glycoproteins and 8 differentially expressed phosphoproteins in the serum of liver cancer patients. Among them, glycoproteins (HP, BCHE, AGT, C3, and PROC) and phosphoproteins (ZYX, GOLM1, GP1BB, CLU, and TNXB) showed upregulation and displayed potential as biomarkers for liver cancer.
Subject(s)
Dipeptides , Glycopeptides , Liver Neoplasms , Phosphopeptides , Tandem Mass Spectrometry , Glycopeptides/blood , Glycopeptides/chemistry , Humans , Phosphopeptides/blood , Phosphopeptides/chemistry , Phosphopeptides/isolation & purification , Tandem Mass Spectrometry/methods , Liver Neoplasms/blood , Dipeptides/blood , Dipeptides/chemistry , Chromatography, Affinity/methods , Polymers/chemistry , Chromatography, Liquid/methods , Hydrophobic and Hydrophilic Interactions , Titanium/chemistryABSTRACT
Sternal osteomyelitis and mediastinitis are rare yet severe complications post-cardiac surgery, often associated with significant morbidity and mortality. Fungal etiologies, particularly those caused by Rhizopus spp., are infrequent but can lead to aggressive infections. Here, we present the case of a 68-year-old male who developed sternal osteomyelitis and mediastinitis caused by Rhizopus spp. two weeks following coronary artery bypass grafting surgery. Debridement and pectoralis flap reconstruction were performed following clinical identification and confirmation with microbiological examinations and a CT scan. Prompt recognition, aggressive surgical intervention, and targeted antifungal therapy were crucial for successful management. This case underscores the importance of considering fungal pathogens, such as Rhizopus, in the differential diagnosis of post-cardiac surgery infections, as well as aggressive treatment to improve outcomes for affected patients.
ABSTRACT
A porphyrin-based titanium-rich porous organic polymer (Th-PPOPs@Ti4+) was designed based on immobilized metal ion affinity chromatography technique and successfully applied to phosphopeptide enrichment with 5,10,15,20-tetrakis(4-carboxyphenyl) porphine tetramethyl ester (TCPTE), 2,3-dihydroxyterephthalaldehyde (DHTA), and 2,3,4-trihydroxybenzaldehyde (THBA) as raw materials. Th-PPOPs@Ti4+ exhibited remarkable sensitivity (0.5 fmol), high selectivity (ß-casein: BSA = 1:2000, molar ratio), outstanding recovery (95.0 ± 1.9%), reusability (10 times), and superior loading capacity (143 mg·g-1). In addition, Th-PPOPs@Ti4+ exhibited excellent ability to specifically capture phosphopeptides from the serum of colorectal cancer (CRC) individuals and normal subjects. Sixty phosphopeptides assigned to 35 phosphoproteins were obtained from the serum of CRC individuals, and 43 phosphopeptides allocated to 28 phosphoproteins were extracted in the serum of healthy individuals via nano-LC-MS/MS. Gene ontology assays revealed that the detected phosphoproteins may be inextricably tied to CRC-associated events, including response to estrogen, inflammatory response, and heparin binding, suggesting that it is possible that these correlative pathways may be implicated in the pathogenesis of CRC.
Subject(s)
Colorectal Neoplasms , Phosphopeptides , Porphyrins , Titanium , Humans , Colorectal Neoplasms/blood , Titanium/chemistry , Phosphopeptides/blood , Phosphopeptides/isolation & purification , Phosphopeptides/chemistry , Porosity , Porphyrins/chemistry , Polymers/chemistryABSTRACT
In recent years, fatty acids containing conjugated CCs have attracted extensive research attention due to their biological activities against human diseases. However, their differentiation is challenging. This study developed a comprehensive analytical solution to accurately differentiate cis/trans-fatty acid isomers using ion mobility mass spectrometry (IM-MS) and theoretical calculations. Cis/trans-fatty acids were mobility-differentiated via simple complexation with 1,5,9-triazacyclododecane (9C3N) or 1,4,8,11-tetraazacyclotetradecane (10C4N) and metal ions, obtaining baseline separation with a peak-to-peak resolution of 0.35-0.92. Moreover, the conformation of the complexes was optimized theoretically, revealing different binding modes between the cis/trans-fatty acid-9C3N/10C4N-metal ion systems, yielding in-depth structural data on the complexes and elucidating the principles of mobility separation. Furthermore, the proposed method was assessed in terms of quantification, accuracy, and precision repeatability. Finally, the method was applied to analyze oil samples. Given its simplicity, speed, and lack of chemical derivatization or chromatographic separation, this technique has potential applications in food analysis.
Subject(s)
Fatty Acids, Unsaturated , Ion Mobility Spectrometry , Ion Mobility Spectrometry/methods , Isomerism , Fatty Acids, Unsaturated/chemistry , Mass SpectrometryABSTRACT
In the present study, click chemistry and Schiff base reactions were simultaneously applied to prepare polymer brush (PEG)-functionalized MOF materials (UiO-66-NH2) and immobilized with Ti4+ (MOF-Brush-THBA-Ti4+) for phosphopeptide analysis. The material has a detection limit of 0.5 fmol, a selectivity of 2000:1, and a loading capacity of 133 mg/g for phosphopeptides. It also demonstrated great repeatability (10 cycles) and recovery rate (96.7 ± 1.4%). During the analysis of bio-samples, 4 specific phosphopeptides were identified in endogenous breast cancer serum, while 11 phosphopeptides were identified in skimmed milk. Moreover, 47 phosphopeptides correlated with 29 phosphorylated proteins were selectively identified from normal control serum, and 66 phosphopeptides correlated with 26 phosphorylated proteins were identified from breast cancer serum. Further analysis of gene ontology (GO) revealed that the detected phosphorylated proteins associated with breast cancer included positive regulation of receptor-mediated endocytosis, proteolysis, extracellular exosome, heparin binding, and chaperone binding. These findings suggest that these associated pathways might contribute to the etiology of breast cancer. Overall, this application exhibits enormous potential in the identification of phosphorylated peptides within bio-samples.
Subject(s)
Metal-Organic Frameworks , Milk , Phosphopeptides , Titanium , Zirconium , Humans , Phosphopeptides/blood , Phosphopeptides/chemistry , Titanium/chemistry , Zirconium/chemistry , Metal-Organic Frameworks/chemistry , Milk/chemistry , Animals , Polymers/chemistry , Female , Breast Neoplasms/blood , Limit of Detection , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization/methodsABSTRACT
The development of simple and rapid analytical tools for gossypol (GSP) is important to the food industry and medical field. Here, we report a matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) method for the detection of GSP by using a reactive matrix 4-hydrazinoquinazoline (4-HQ). The two aldehyde groups of GSP react with the 4-HQ and therefore improve the detection sensitivity and selectivity of GSP. Moreover, GSP forms homogeneous crystals with the 4-HQ matrix, allowing the quantification of the GSP by the proposed method. With the optimized experimental conditions, GSP could be detected at concentrations as low as 0.1 µM and quantified in a wide linear range (1-500 µM). After a brief extraction with an organic solvent, the GSP contents in cottonseeds and cottonseed kernels from different provinces of China were determined successfully. The spiked recovery of GSP in cottonseed/cottonseed kernel samples was obtained as 97.88-105.80%, showing the reliability of the assay for GSP determination in real samples.
Subject(s)
Gossypol , Limit of Detection , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization/methods , Gossypol/analysis , Gossypol/chemistry , Gossypium/chemistry , Reproducibility of ResultsABSTRACT
Rhodotorula mucilaginosa fungemia is rare and highly resistant to antifungal therapy. We herein report a case involving a 31-year-old male admitted after a high-velocity road traffic accident. He sustained a grade IV liver injury with right hepatic vein thrombosis, which necessitated an urgent laparotomy. Post-operatively, repeated imaging of the abdomen revealed the presence of a biloma. Percutaneous subdiaphragmatic drainage was carried out but appeared ineffective, prompting a second surgery for an urgent hemi-hepatectomy. The patient was then nursed in the intensive care unit (ICU); however, during his stay in the ICU, he became more sepsis, which was evident by worsening ventilatory support and a rise in septic parameters from the biochemistry parameters. Despite intravenous piperacillin-tazobactam and fluconazole, his septic parameters did not improve and a full septic workup was conducted and was found to be positive for Rhodotorula mucilaginosa from the blood cultures. After discussion with the infectious disease physicians and clinical microbiologists, it was decided to initiate a course of intravenous meropenem and amphotericin B based on minimum inhibitory concentration (MIC) values, considering the patient's extended ICU stay and catheter use. Eventually, after successfully weaning off mechanical ventilation, the patient was discharged from ICU care. This case underscores the necessity of individualized approaches, combining timely imaging, appropriate drainage techniques, and tailored treatments to optimize outcomes for such intricate post-traumatic complications.
ABSTRACT
The elucidation of disease pathogenesis can be achieved by analyzing the low-abundance phosphopeptides in organisms. Herein, we developed a novel and easy-to-prepare polymer-coated nanomaterial. By improving the hydrophilicity and spatial conformation of the material, we effectively enhanced the adsorption of phosphopeptides and demonstrated excellent enrichment properties. The material was able to successfully enrich the phosphopeptides in only 1 min. Meanwhile, the material has high selectivity (1:2000), good loading capacity (100 µg/mg), excellent sensitivity (0.5 fmol), and great acid and alkali resistance. In addition, the material was applied to real samples, and 70 phosphopeptides were enriched from the serum of Parkinson's disease (PD) patients and 67 phosphopeptides were enriched from the serum of normal controls. Sequences Logo showed that PD is probably associated with threonine, glutamate, serine, and glutamine. Finally, gene ontology (GO) analysis was performed on phosphopeptides enriched in PD patients' serum. The results showed that PD patients expressed abnormal expression of the cholesterol metabolic process and cell-matrix adhesion in the biological process (BP), endoplasmic reticulum and lipoprotein in the cellular component (CC), and heparin-binding, lipid-binding, and receptor-binding in the molecular function (MF) as compared with normal individuals. All the experiments indicate that the nanomaterials have great potential in proteomics studies.
Subject(s)
Nanostructures , Parkinson Disease , Phosphopeptides , Polymers , Parkinson Disease/blood , Humans , Phosphopeptides/blood , Polymers/chemistry , Nanostructures/chemistry , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization/methodsABSTRACT
Osteoporosis characterized by decreased bone density and mass, is a systemic bone disease with the destruction of microstructure and increase in fragility. Osteoporosis is attributed to multiple causes, including aging, inflammation, diabetes mellitus, and other factors induced by the adverse effects of medications. Without treatment, osteoporosis will further progress and bring great trouble to human life. Due to the various causes, the treatment of osteoporosis is mainly aimed at improving bone metabolism, inhibiting bone resorption, and promoting bone formation. Although the currently approved drugs can reduce the risk of fragility fractures in individuals, a single drug has limitations in terms of safety and effectiveness. By contrast, traditional Chinese medicine (TCM), a characteristic discipline in China, including syndrome differentiation, Chinese medicine prescription, and active ingredients, shows unique advantages in the treatment of osteoporosis and has received attention all over the world. Therefore, this review summarized the pathogenic factors, pathogenesis, therapy limitations, and advantages of TCM, aiming at providing new ideas for the prevention and treatment of OP.
ABSTRACT
Cornus officinalis, a medicinal and edible plant known for its liver-nourishing properties, has shown promise in inhibiting the activation of hepatic stellate cells (HSCs), crucial indicators of hepatic fibrosis, especially when processed by high pressure wine steaming (HPWS). Herein, this study aims to investigate the regulatory effects of cornus officinalis, both in its raw and HPWS forms, on inflammation and apoptosis in liver fibrosis and their underlying mechanisms. In vivo liver fibrosis models were established by subcutaneous injection of CCl4, while in vitro HSCs were exposed to transforming growth factor-ß (TGF-ß). These findings demonstrated that cornus officinalis with HPWS conspicuously ameliorated histopathological injury, reduced the release of proinflammatory factors, and decreased collagen deposition in CCl4-induced rats compared to its raw form. Utilizing ultra-high-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometer (UHPLC-QTOF-MS) combined with network analysis, we identified that the pharmacological effects of the changed components of cornus officinalis before and after HPWS, primarily centered on the adenosine phosphate (AMP)-activated protein kinase (AMPK) pathway. Of note, cornus officinalis activated AMPK and Sirtuin 3 (SIRT3), promoting the apoptosis of activated HSCs through the caspase cascade by regulating caspase3, caspase6 and caspase9. siRNA experiments showed that cornus officinalis could regulate AMPK activity and its mediated-apoptosis through SIRT3. In conclusion, cornus officinalis exhibited the ability to reduce inflammation and apoptosis, with the SIRT3-AMPK signaling pathway identified as a potential mechanism underlying the synergistic effect of cornus officinalis with HPWS on anti-liver fibrosis.
ABSTRACT
The interaction between microplastics (MPs) and cadmium (Cd) poses a threat to agricultural soil environments, and their effects on plant growth and rhizosphere microbial community functions are not yet clear. In this study, energy sorghum was used as a test plant to investigate the effects of two types of MPs, polystyrene (PS) and polyethylene (PE), at different particle sizes (13 µm, 550 µm) and concentrations (0.1%, 1% w/w), and Cd, as well as their interactions, on the growth of sorghum in a soil-cultivation pot experiment. The results showed that the combined effects of MP and Cd pollution on the dry weight and Cd accumulation rate in sorghum varied depending on the type, concentration, and particle size of the MPs, with an overall trend of increasing stress from combined pollution with increasing Cd content and accumulation. High-throughput sequencing analysis revealed that combined MP and Cd pollution increased bacterial diversity, and the most significant increase was observed in the abundance-based coverage estimator (ACE), Shannon, and Sobs indices in the 13 µm 1% PS+Cd treatment group. Metagenomic analysis based on the Kyoto Encyclopedia of Genes and Genomes (KEGG) metabolic pathways revealed that 19 groups of metabolic pathways, including microbial metabolism and methane metabolism, differed significantly under combined MP and Cd pollution. Hierarchical clustering results indicated that Cd treatment and combined MP and Cd treatment affected the abundances of sorghum rhizosphere soil nitrogen (N) and phosphorus (P) cycling genes and that the type of MP present was an important factor affecting N and P cycling genes. The results of this study provide a basis for exploring the toxic effects of combined MP and Cd pollution and for conducting soil environmental risk assessments.
Subject(s)
Cadmium , Microplastics , Rhizosphere , Soil Microbiology , Soil Pollutants , Sorghum , Sorghum/drug effects , Sorghum/microbiology , Cadmium/toxicity , Soil Pollutants/toxicity , Microplastics/toxicity , Soil/chemistry , Particle Size , Bacteria/drug effectsABSTRACT
Sirtuin3 (SIRT3) is a nicotinamide adenine dinucleotide (NAD+)-dependent protein deacetylase located in the mitochondria, which mainly regulates the acetylation of mitochondrial proteins. In addition, SIRT3 is involved in critical biological processes, including oxidative stress, inflammation, DNA damage, and apoptosis, all of which are closely related to the progression of liver disease. Liver fibrosis characterized by the deposition of extracellular matrix is a result of long termed or repeated liver damage, frequently accompanied by damaged hepatocytes, the recruitment of inflammatory cells, and the activation of hepatic stellate cells. Based on the functions and pharmacology of SIRT3, we will review its roles in liver fibrosis from three aspects: First, the main functions and pharmacological effects of SIRT3 were investigated based on its structure. Second, the roles of SIRT3 in major cells in the liver were summarized to reveal its mechanism in developing liver fibrosis. Last, drugs that regulate SIRT3 to prevent and treat liver fibrosis were discussed. In conclusion, exploring the pharmacological effects of SIRT3, especially in the liver, may be a potential strategy for treating liver fibrosis.
Subject(s)
Liver Diseases , Sirtuin 3 , Humans , Sirtuin 3/genetics , Sirtuin 3/metabolism , Mitochondrial Proteins , Oxidative Stress/physiology , Liver Cirrhosis/drug therapyABSTRACT
Exosomes have gained recognition as valuable reservoirs of biomarkers, holding immense potential for early cancer detection. Consequently, there is a pressing need for the development of an economical and highly sensitive exosome detection methodology. In this work, we present a fluorescence method for breast cancer-derived exosome detection based on Cu-triggered click reaction of azide-modified CD63 aptamer and alkyne functionalized Pdots. The detection threshold for the exosomes obtained from the breast cancer serum was determined to be 6.09 × 107 particles per µL, while the measurable range spanned from 6.50 × 107 to 1.30 × 109 particles per µL. The employed methodology achieved notable success in accurately distinguishing breast cancer patients from healthy individuals through serum analysis. The application of this method showcases the significant potential for early exosome analysis in the clinical diagnosis of breast cancer patients.
Subject(s)
Alkynes , Aptamers, Nucleotide , Azides , Biosensing Techniques , Breast Neoplasms , Click Chemistry , Exosomes , Tetraspanin 30 , Humans , Breast Neoplasms/blood , Female , Exosomes/chemistry , Tetraspanin 30/metabolism , Aptamers, Nucleotide/chemistry , Biosensing Techniques/methods , Azides/chemistry , Alkynes/chemistry , Fluorescent Dyes/chemistry , Polymers/chemistryABSTRACT
Composite pollution by microplastics and heavy metals poses a potential threat to the soilplant system and has received increasing attention. Plant growth-promoting bacteria (PGPB) have good application potential for the remediation of combined microplastic and heavy metal pollution, but few related studies exist. The present study employed a pot experiment to investigate the effects of inoculation with the PGPB Bacillus sp. SL-413 and Enterobacter sp. VY-1 on sorghum growth and Cd accumulation under conditions of combined cadmium (Cd) and polyethylene (PE) pollution. Cd+PE composite contamination led to a significant reduction in sorghum length and biomass due to increased toxicity. Inoculation with Bacillus sp. SL-413 and Enterobacter sp. VY-1 alleviated the stress caused by Cd+PE complex pollution, and the dry weight of sorghum increased by 25.7% to 46.1% aboveground and by 12.3% to 45.3% belowground. Bacillus sp. SL-413 and Enterobacter sp. VY-1 inoculation increased the Cd content and accumulation in sorghum and improved the phytoremediation efficiency of Cd. The inoculation treatment effectively alleviated the nutrient stress caused by the reduction in soil mineral nutrients due to Cd+PE composite pollution. The composition of the soil bacterial communities was also affected by the Cd, Cd+PE and bacterial inoculation treatments, which affected the diversity of the soil bacterial communities. Network analyses indicated that bacterial inoculation regulated the interaction of rhizospheric microorganisms and increased the stability of soil bacterial communities. The Mantel test showed that the changes in the soil bacterial community and function due to inoculation with Bacillus sp. SL-413 and Enterobacter sp. VY-1 were important factors influencing sorghum growth and Cd remediation efficiency. The results of this study will provide new evidence for the research on joint plantmicrobe remediation of heavy metal and microplastic composite pollution.
Subject(s)
Bacillus , Metals, Heavy , Soil Pollutants , Sorghum , Cadmium/analysis , Biodegradation, Environmental , Plastics , Polyethylene , Soil , Rhizosphere , Microplastics , Metals, Heavy/toxicity , Metals, Heavy/analysis , Enterobacter , Soil Pollutants/analysisABSTRACT
Reinforcement learning (RL) stands as one of the three fundamental paradigms within machine learning and has made a substantial leap to build general-purpose learning systems. However, using traditional electrical computers to simulate agent-environment interactions in RL models consumes tremendous computing resources, posing a significant challenge to the efficiency of RL. Here, we propose a universal framework that utilizes a photonic integrated circuit (PIC) to simulate the interactions in RL for improving the algorithm efficiency. High parallelism and precision on-chip optical interaction calculations are implemented with the assistance of link calibration in the hybrid architecture PIC. By introducing similarity information into the reward function of the RL model, PIC-RL successfully accomplishes perovskite materials synthesis task within a 3472-dimensional state space, resulting in a notable 56% improvement in efficiency. Our results validate the effectiveness of simulating RL algorithm interactions on the PIC platform, highlighting its potential to boost computing power in large-scale and sophisticated RL tasks.
ABSTRACT
A visible-light-induced radical cyclization reaction of o-vinylaryl isocyanides and oxime esters to access various 2,4-disubstituted quinolines was disclosed. Oxime esters were employed as acyl radical precursors via the carbon-carbon bond cleavage. It provided an effective way for the synthesis of 2-acyl-4-arlysubstituted quinolines under mild conditions and exhibited good functional group tolerance and substrate applicability.
ABSTRACT
The high expression or mutation of SHP2 can induce cancer, so targeting SHP2 has become a new strategy for cancer treatment. In this study, we used the previously reported SHP2 allosteric inhibitor IACS-13909 as a lead drug for structural derivation and modification, and synthesized three SHP2 inhibitors. Among them, 1H-pyrazolo[3,4-b]pyrazine derivative 4b was a highly selective SHP2 allosteric inhibitor, with an IC50 value of 3.2 nM, and its inhibitory activity was 17.75 times than that of the positive control IACS-13909. The cell proliferation experiment detected that compound 4b would markedly inhibit the proliferation of various cancer cells. Interestingly, compound 4b was highly sensitive to KRASG12C-mutant non-small cell lung cancer NCI-H358 cells, with an IC50 value of 0.58 µM and its antiproliferative activity was 4.79 times than that of IACS-13909. Furthermore, the combination therapy of compound 4b and KRASG12C inhibitor sotorasib would play a strong synergistic effect against NCI-H358 cells. The western blot experiment detected that compound 4b markedly downregulated the phosphorylation levels of ERK and AKT in NCI-H358 cells. Molecular docking study predicted that compound 4b bound to the allosteric site of SHP2 and formed H-bond interactions with key residues Thr108, Glu110, Arg111, and Phe113. In summary, this study aims to provide new ideas for the development of SHP2 allosteric inhibitors for the treatment of KRASG12C mutant non-small cell lung cancer.Communicated by Ramaswamy H. Sarma.
ABSTRACT
The identification of positional isomers is of interest because different isomers have different chemical or biological functions and applications. The analysis of positional isomers is sometimes challenging since they have similar chemical structures and properties. For example, the analysis of mass cannot identify different positional isomers because they have identical mass-to-charge ratios and show a single mass peak in mass spectrometry. In this study, an efficient and simple qualitative and quantitative analytical method for differentiating 2,2'-bipyridine-3,3'-dicarboxylic acid (3,3'-BDA), 2,2'-bipyridine-4,4'-dicarboxylic acid (4,4'-BDA), and 2,2'-bipyridine-5,5'-dicarboxylic acid (5,5'-BDA) was developed by using ion mobility spectrometry (IMS). The results revealed that the three BDA isomers formed non-covalent complexes with cyclodextrins (CDs) and Mg2+ ions in the gas phase: [ß-CD+3,3'/4,4'/5,5'-BDA+Mg]2+ and [γ-CD+3,3'/4,4'/5,5'-BDA+Mg]2+, which were distinguished by measuring the mobility of the complexes because of their spatial conformational differences. The peak-to-peak resolution (Rp-p) values of the three isomers of [γ-CD+3,3'/4,4'/5,5'-BDA+Mg]2+ reached 2.983 and 2.892, respectively. The conformations of the ternary complexes simulated by the theoretical calculations revealed the different interactions and shapes of the stereoisomers, and the predicted results agreed with the experimental results. Simultaneously, further studies on the collisional dissociation of the ternary complexes revealed that the dissociation energies of the different complex ions varied were different owing to the diverse different conformations. Finally, the relative quantitative analysis of the different isomers in mixed samples was performed and satisfactory linearity results (R2 > 0.99) were obtained. Thus, an effective analytical method was proposed for the identification and quantification of BDA isomers without chemical derivatization, offering a promising approach for the identification of similar derivatives or positional isomers that could be applied in various fields including chemicals and pharmaceuticals.