Mechanisms of brain damage caused by inorganic fluoride using proteomics-based techniques / 环境与职业医学

Background Chronic excessive exposure to fluoride can cause damage to the central nervous system and a certain degree of learning and memory impairment. However, the associated mechanism is not yet clear and further exploration is needed. Objective Using 4D unlabelled quantitative proteomics techniques to explore differentially expressed proteins and their potential mechanisms of action in chronic excessive fluoride exposure induced brain injury. Methods Twenty-four SPF-grade adult SD rats, half male and half male, were selected and divided into a control group and a fluoride group by random number table method, with 12 rats in each group. Among them, the control group drank tap water (fluorine content<1 mg·L−1), the fluoride group drank sodium fluoride solution (fluorine content 10 mg·L−1), and both groups were fed with ordinary mouse feed (fluoride content<0.6 mg·kg−1). After 180 d of feeding, the SD rats were weighed, and then part of the brain tissue was sampled for pathological examination by hematoxylin-eosin (HE) staining and Nissl staining. The rest of the brain tissue was frozen and stored at −80 ℃. Three brain tissue samples from each group were randomly selected for proteomics detection. Differentially expressed proteins were screened and subcellular localization analysis was performed, followed by Gene Ontology (GO) function analysis, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis, cluster analysis, and protein-protein interaction analysis. Finally, Western blotting was used to detect the expression levels of key proteins extracted from the brain tissue samples. Results After 180 d of feeding, the average weight of the rats in the fluoride group was significantly lower than that in the control group (P<0.05). The brain tissue stained with HE showed no significant morphological changes in the cerebral cortex of the fluoride treated rats, and neuron loss, irregular arrangement of neurons, eosinophilic changes, and cell body pyknosis were observed in the hippocampus. The Nissl staining results showed that the staining of neurons in the cerebral cortex and hippocampus of rats exposed to fluoride decreased (Nissl bodies decreased). The proteomics results showed that a total of 6927 proteins were identified. After screening, 206 differentially expressed proteins were obtained between the control group and the fluoride group, including 96 up-regulated proteins and 110 down-regulated proteins. The differential proteins were mainly located in cytoplasm (30.6%), nucleus (27.2%), mitochondria (13.6%), plasma membrane (13.6%), and extracellular domain (11.7%). The GO analysis results showed that differentially expressed proteins mainly participated in biological processes such as iron ion transport, regulation of dopamine neuron differentiation, and negative regulation of respiratory burst in inflammatory response, exercised molecular functions such as ferrous binding, iron oxidase activity, and cytokine activity, and were located in the smooth endoplasmic reticulum membrane, fixed components of the membrane, chloride channel complexes, and other cellular components. The KEGG significantly enriched pathways included biosynthesis of secondary metabolites, carbon metabolism, and microbial metabolism in diverse environments. The results of differential protein-protein interaction analysis showed that the highest connectivity was found in glucose-6-phosphate isomerase (Gpi). The expression level of Gpi in the brain tissue of the rats in the fluoride group was lower than that in the control group by Western blotting (P<0.05). Conclusion Multiple differentially expressed proteins are present in the brain tissue of rats with chronic fluorosis, and their functions are related to biosynthesis of secondary metabolites, carbon metabolism, and microbial metabolism in diverse environments; Gpi may be involved in cerebral neurological damage caused by chronic overdose fluoride exposure.

Application of proteomics technology in dry eye disease and acupuncture treatment / 国际眼科杂志(Guoji Yanke Zazhi)

Dry eye disease(DED)refers to a condition characterized by reduced stability of the tear film or an imbalance in the microenvironment of the ocular surface, resulting from abnormalities in quality, quantity and kinetics of tear. This condition leads to various ocular discomforts and even visual impairment. The pathogenesis of DED is multifactorial and current treatment mainly focuses on symptom relief and preservation of visual function. Acupuncture has shown effectiveness in treating dry eye, although its underlying mechanism remains incompletely understood. Proteomics technology offers a comprehensive and systematic approach to studying the functions, structures and interactions of proteins. Its application in DED research can provide valuable insights into the dynamic changes in protein levels associated with different etiology or the course of DED and facilitate the identification of potential biomarkers. Furthermore, proteomics can systematically explore the regulatory mechanisms underlying acupuncture treatment for DED, providing a theoretical basis for acupuncture treatment research and contributing to the understanding of its effects at a fundamental level. This paper aims to explore the potential application of proteomics in both clinical and basic research on DED. Ultimately, it strives to offer scientific and effective strategies for the diagnosis and treatment of DED and advance our knowledge of the mechanisms underlying acupuncture therapy.

Comparative proteomics of proliferative diabetic retinopathy in people with Type 2 diabetes highlights the role of inflammation, visual transduction, and extracellular matrix pathways

Purpose: To explore the vitreous humor proteome from type 2 diabetes subjects with proliferative diabetic retinopathy (PDR) in the Indian population. Methods: We performed mass spectrometry?based label?free quantitative analysis of vitreous proteome of PDR (n = 13) and idiopathic macular hole (IMH; control) subjects (n = 14). Nine samples of PDR and 10 samples of IMH were pooled as case and control, respectively, and compared. Four samples each of PDR and IMH were analyzed individually without pooling to validate the results of the pooled analysis. Comparative quantification was performed using Scaffold software which calculated the fold changes of differential expression. Bioinformatics analysis was performed using DAVID and STRING software. Results: We identified 469 proteins in PDR and 517 proteins in IMH vitreous, with an overlap of 172 proteins. Also, 297 unique proteins were identified in PDR and 345 in IMH. In PDR vitreous, 37 proteins were upregulated (P < 0.05) and 19 proteins were downregulated compared to IMH. Protein distribution analysis clearly demonstrated a separation of protein expression in PDR and IMH. Significantly upregulated proteins included fibrinogen gamma chain, fibrinogen beta chain, and carbonic anhydrase 1 and downregulated proteins included alpha?1?antitrypsin, retinol?binding protein 3, neuroserpin, cystatin C, carboxypeptidase E and cathepsin?D. Conclusion: Diabetic retinopathy pathogenesis involves proteins which belong to inflammation, visual transduction, and extracellular matrix pathways. Validation?based experiments using enzyme?linked immunosorbent assay (ELISA) or western blotting are needed to establish cause and effect relationships of these proteins to the disease state, to develop them as biomarkers or drug molecules

Identification of potential urinary protein biomarkers in colorectal cancer: a pilot study using a proteomic approach

Colorectal cancer (CRC) is among the most diagnosed malignancies worldwide, and it is also the second leading cause of cancer-related deaths. Despite recent progress in screening programs, noninvasive accurate biomarkers are still needed in the CRC field. In this study, we evaluated and compared the urinary proteomic profiles of patients with colorectal adenocarcinoma and patients without cancer, aiming to identify potential biomarker proteins. Urine samples were collected from 9 patients with CRC and 9 patients with normal colonoscopy results. Mass spectrometry (label-free LC—MS/MS) was used to characterize the proteomic profile of the groups. Ten proteins that were differentially regulated were identified between patients in the experimental group and in the control group, with statistical significance with a p value ≤ 0.05. The only protein that presented upregulation in the CRC group was beta-2-microglobulin (B2M). Subsequent studies are needed to evaluate patients through different analysis approaches to independently verify and validate these biomarker candidates in a larger cohort sample. (AU)

Profiling of idiopathic macular hole vitreous proteome identifies the role of extracellular matrix remodelling, epithelial–mesenchymal transformation and unfolded protein-response pathways

Purpose: To analyze and describe the proteome of the vitreous humour in eyes with idiopathic macular holes. Methods: We performed mass spectrometry (MS)?based label?free quantitative analysis of the vitreous proteome of idiopathic macular hole (IMH) and control donor vitreous. Comparative quantification was performed using SCAFFOLD software which calculated fold changes of differential expression. Bioinformatics analysis was performed using DAVID and STRING software. Results: A total of 448 proteins were identified by LC?MS/MS in IMH and cadaveric eye vitreous samples, of which 199 proteins were common. IMH samples had 189 proteins that were unique and 60 proteins were present only in the control cadaveric vitreous. We found upregulation of several extracellular matrix (ECM) and cytoskeletal proteins, namely collagen alpha?1 (XVIII) chain, N?cadherin, EFEMP1/fibulin?3, basement membrane?specific heparan sulfate proteoglycan core protein, and target of Nesh?3. Several cytoskeleton proteins, namely tubulin, actin, and fibronectin levels, were significantly lower in IMH vitreous, probably reflecting increased ECM degradation. IMH vitreous also had a downregulation of unfolded protein response?mediated?mediated apoptosis proteins, possibly related to a state of increased cell survival and proliferation, along with a remodelling and aberrant production of ECM contents. Conclusion: The pathogenesis of macular holes may involve ECM remodelling, epithelial–mesenchymal transformation, downregulation of apoptosis, protein folding defects, and complement pathway. The vitreo?retinal milieu in macular holes contain molecules related to both ECM degradation and inhibition of the same, thereby maintaining a homeostasis.

Optimization and evaluation of tear protein elution from Schirmer’s strips in dry eye disease

Purpose: Extraction of tear protein from Schirmer’s strip is a prerequisite for the proper identification and screening of biomarkers in dry eye disease. The study compares different methods of extraction of tear proteins from the Schirmer’s strip. Methods: Reflex tear was collected from healthy controls (HC; n = 12), Stevens–Johnson syndrome (SJS; n = 3) and dry eye disease (DED; n = 3) patients using capillary tube. This tear was used to measure the volume absorbed by Schirmer’s strip per microliter. Different buffers (6) were used to compare the protein yield from the Schirmer’s strip in four different conditions. The tear proteins extracted using the highest protein yield buffer were analyzed by mass spectrometry. Results: A linear relationship between the tear volume and wetting length was observed (r = 0.0.997, n = 6). The highest yield was observed after incubation of the Schirmer’s strip in 100 mM ammonium bicarbonate (ABC) with 0.25% Nonidet P?40(NP?40) at 4°C for an hour (P < 0.00005). The in?solution digestion of tear eluted in the above condition 100 Mm ABC + 0.25% NP?40 with one?hour incubation yielded a total of 2119 proteins in HC, SJS, and DED. The unique protein observed in SJS and DED was 0.6% and 17.9%, respectively. The significantly expressed proteins are associated with innate immune response, proteolysis, wound healing, and defense response. Conclusion: A method for extraction of protein from Schirmer’s strip was optimized for increase in protein yield from the tear sample. SJS and DED tear samples have unique protein signature. The study will aid in better design of tear protein?based experimental study.

Dried blood spots: a robust tool for malaria surveillance in countries targeting elimination

With the advancements in analytical and molecular techniques, Dried Blood Spots (DBS) are re-emerging as attractive and cost-effective alternatives for global health surveillance. The use of DBS has been well-characterized in the neonatal screening of metabolic diseases, therapeutic screening as well as in epidemiological studies for biomonitoring. Malaria is one such infectious disease where DBS use can expedite molecular surveillance for assessing drug resistance and for refining drug usage policies. In India, malaria cases have reduced significantly over the past decade but to achieve malaria elimination by 2030, country-wide DBS-based screening should be conducted to identify the presence of molecular markers of artemisinin resistance and to study parasite reservoirs in asymptomatic populations. DBS has wide applications in genomics, proteomics, and metabolomic studies concerning both host and pathogen factors. Hence, it is a comprehensive tool for malaria surveillance that can capture both host and parasite information. In this review, we elucidate the current and prospective role of DBS in malaria surveillance and its applications in studies ranging from genetic epidemiology, parasite and vector surveillance, drug development and polymorphisms to ultimately how they can pave the roadmap for countries aiming malaria elimination

Metabolic effect of low fluoride levels in the islets of NOD mice: integrative morphological, immunohistochemical, and proteomic analyses

Abstract Fluoride (F) has been widely used to control dental caries, and studies suggest beneficial effects against diabetes when a low dose of F is added to the drinking water (10 mgF/L). Objectives This study evaluated metabolic changes in pancreatic islets of NOD mice exposed to low doses of F and the main pathways altered by the treatment. Methodology In total, 42 female NOD mice were randomly divided into two groups, considering the concentration of F administered in the drinking water for 14 weeks: 0 or 10 mgF/L. After the experimental period, the pancreas was collected for morphological and immunohistochemical analysis, and the islets for proteomic analysis. Results In the morphological and immunohistochemical analysis, no significant differences were found in the percentage of cells labelled for insulin, glucagon, and acetylated histone H3, although the treated group had higher percentages than the control group. Moreover, no significant differences were found for the mean percentages of pancreatic areas occupied by islets and for the pancreatic inflammatory infiltrate between the control and treated groups. Proteomic analysis showed large increases in histones H3 and, to a lesser extent, in histone acetyltransferases, concomitant with a decrease in enzymes involved in the formation of acetyl-CoA, besides many changes in proteins involved in several metabolic pathways, especially energy metabolism. The conjunction analysis of these data showed an attempt by the organism to maintain protein synthesis in the islets, even with the dramatic changes in energy metabolism. Conclusion Our data suggests epigenetic alterations in the islets of NOD mice exposed to F levels comparable to those found in public supply water consumed by humans.

Salivary protein candidates for biomarkers of oral disorders in people with a crack cocaine use disorder

Abstract The use of cocaine and its main derivative, crack, can cause some systemic effects that may lead to the development of some oral disorders. Objective To assess the oral health of people with a crack cocaine use disorder and identify salivary protein candidates for biomarkers of oral disorders. Methodology A total of 40 volunteers hospitalized for rehabilitation for crack cocaine addiction were enrolled; nine were randomly selected for proteomic analysis. Intraoral examination, report of DMFT, gingival and plaque index, xerostomia, and non-stimulated saliva collection were performed. A list of proteins identified was generated from the UniProt database and manually revised. Results The mean age (n=40) was 32 (±8.88; 18-51) years; the mean DMFT index was 16±7.70; the mean plaque and gingival index were 2.07±0.65 and 2.12±0.64, respectively; and 20 (50%) volunteers reported xerostomia. We identified 305 salivary proteins (n=9), of which 23 were classified as candidate for biomarkers associated with 14 oral disorders. The highest number of candidates for biomarkers was associated with carcinoma of head and neck (n=7) and nasopharyngeal carcinoma (n=7), followed by periodontitis (n=6). Conclusions People with a crack cocaine use disorder had an increased risk of dental caries and gingival inflammation; less than half had oral mucosal alterations, and half experienced xerostomia. As possible biomarkers for 14 oral disorders, 23 salivary proteins were identified. Oral cancer and periodontal disease were the most often associated disorders with biomarkers.

Research progress in multi-omics biomarkers involved in post-traumatic stress disorder / 中华创伤杂志

Post-traumatic stress disorder (PTSD) is a psychiatric illness induced by exposure to severe stress-induced traumatic events. Repeated traumatic re-experience, avoidance, negative cognition and emotional changes seriously reduce the quality of life of PTSD patients. Currently, it is urgent to further clarify the etiology and molecular mechanism of PTSD in order to guide the diagnosis and treatment of PTSD. Considering the underlying pathophysiology is not entirely known, to identify the pertinent biomarkers of PTSD is critical in researching its incidence and progression. In contrast with the single-omics researches, multi-omics studies may methodically expand on biomolecular interactions from a range of angles, creating a new potential to comprehend the development of complicated human illnesses. Therefore, the authors review the research progress in PTSD biomarkers from aspects of genomics, transcriptomics and proteomics, hoping to provide a reference for future research and treatment of PTSD.

Comprehensive and deep profiling of the plasma proteome with protein corona on zeolite NaY / 药物分析学报

Proteomic characterization of plasma is critical for the development of novel pharmacodynamic bio-markers.However,the vast dynamic range renders the profiling of proteomes extremely challenging.Here,we synthesized zeolite NaY and developed a simple and rapid method to achieve comprehensive and deep profiling of the plasma proteome using the plasma protein corona formed on zeolite NaY.Specifically,zeolite NaY and plasma were co-incubated to form plasma protein corona on zeolite NaY(NaY-PPC),followed by conventional protein identification using liquid chromatography-tandem mass spectrometry.NaY was able to significantly enhance the detection of low-abundance plasma proteins,minimizing the"masking"effect caused by high-abundance proteins.The relative abundance of middle-and low-abundance proteins increased substantially from 2.54％to 54.41％,and the top 20 high-abundance proteins decreased from 83.63％to 25.77％.Notably,our method can quantify approxi-mately 4000 plasma proteins with sensitivity up to pg/mL,compared to only about 600 proteins iden-tified from untreated plasma samples.A pilot study based on plasma samples from 30 lung adenocarcinoma patients and 15 healthy subjects demonstrated that our method could successfully distinguish between healthy and disease states.In summary,this work provides an advantageous tool for the exploration of plasma proteomics and its translational applications.

Inhibitory effects of 1% atropine on form deprivation-induced myopia development in guinea pigs and its mechanism / 中华实验眼科杂志

Objective:To observe the prevention and control effect of 1% atropine on the progression of form deprivation myopia (FDM) in guinea pigs and the potential biological mechanism.Methods:Sixty-nine 3-week-old tricolor guinea pigs with normal refraction were randomly divided into a normal control group ( n=19), a FDM group ( n=19), a FDM+ atropine group ( n=19), and an atropine group ( n=12). No intervention was given to guinea pigs in normal control group.The FDM model was established by covering the right eye of guinea pigs with a semitransparent latex facemask for 4 weeks in FDM and FDM+ atropine groups.For the FDM+ atropine group, 1% atropine gel was topically administered to the form-deprived right eyes once a day for 4 weeks.For the atropine group, the right eye was treated with 1% atropine gel once a day for 4 weeks.Refraction and axial length of guinea pigs were measured by retinoscopy and ophthalmic A-scan ultrasonography respectively at baseline, experiment week 2 and week 4.In experiment week 4, eyeballs were enucleated to make sections via the paraffin wax processing procedure, and the microstructural and ultrastructural changes of the sclera were observed under the light microscope and transmission electron microscope, respectively.The isobaric tags for relative and absolute quantitation labeling combined with liquid chromatography-tandem mass spectrometry were used to identify the differentially expressed proteins.Use and care of the animals complied with the Regulation for the Administration of Affairs Concerning Experiment Animals by State Science and Technology Commission.The study protocol was approved by the Institutional Animal Care and Use Committee of Tianjin Medical University (No.TJYY2020111028). Results:There were statistically significant differences in the diopter of guinea pigs at different time points among the four groups ( Fgroup=138.892, P<0.001; Ftime=167.270, P<0.001). Compared with normal control group, the diopter of guinea pigs in FDM group at experiment weeks 2 and 4, and FDM+ atropine group at experiment week 4 developed toward myopia, showing statistically significant differences (all at P<0.001). Compared with FDM group, the diopter of guinea pigs in FDM+ atropine group at experiment weeks 2 and 4 developed toward hyperopia, showing statistically significant differences (both at P<0.001). There were statistically significant differences in the axial length of guinea pigs at different time points among the four groups ( Fgroup=32.346, P<0.001; Ftime=353.797, P<0.001). The axial lengths of FDM group at experiment weeks 2 and 4 and FDM+ atropine group at experiment week 4 were longer than those of normal control group, and the axial lengths in FDM+ atropine group at experiment weeks 2 and 4 were shorter than those in FDM group, and the differences were statistically significant (all at P<0.001). The collagenous fibers of posterior sclera of guinea pigs were loose and disordered in FDM group, and were regular in FDM+ atropine group.The posterior scleral thickness of normal control group, FDM group, FDM+ atropine group and atropine group was (141.74±16.98), (101.46±9.15), (112.74±6.24) and (134.30±18.19) μm, respectively, with a statistically significant difference ( F=6.709, P=0.005). The posterior sclera was significantly thinner in FDM group than in normal control group and FDM+ atropine group (both at P<0.05). The diameter of posterior scleral collagen fiber gradually increased from inside to outside in normal control group, FDM+ atropine group and atropine group, and the diameters of the inner, middle and outer posterior scleral collagen fibers were smaller in FDM group than in normal control group.Proteomic analysis revealed 85 differentially expressed proteins (fold change>1.30) between FDM group and normal control group, FDM+ atropine group and FDM group, of which 38 were up-regulated and 47 were down-regulated after atropine treatment.Gene Ontology enrichment analysis showed that biological processes mainly involved were biological regulation, cell process, localization and metabolic process.Molecular function mainly involved were binding, catalytic activity, molecular function regulator, structural molecule activity and transporter activity.Cell components mainly involved were in cellular anatomical entity, intracellular and protein-containing complex. Conclusions:Atropine can increase the diameter of scleral collagen fibers in guinea pigs of FDM model, improve the arrangement of scleral collagen fiber, inhibit scleral thinning.The mechanism of atropine to control myopia progression is closely related to the tight junction between scleral cells, cytoskeleton and extracellular matrix remodeling.

Analyzing the association between polymorphism of CES1 and MUC5B genes and methyl acetate poisoning by whole exome sequencing / 中国职业医学

Objective To detect and analyze the susceptibility genes of methyl acetate poisoning in patients by whole exome sequencing. Methods Two patients with occupational acute severe methyl acetate poisoning and their first-degree relatives who work in the same occupation and position with similar working hours were selected as the research subjects by judgment sampling method. Peripheral blood was collected for whole exome sequencing. The sequencing data was compared with the public genome database to screen the mutation sites and find out the gene sites related to methyl acetate poisoning. The suspected pathogenic mutation genes were annotated and interpreted. Results The results of whole exome sequencing showed that there were 40 differential genes between the patients with methyl acetate poisoning and their first-degree relatives, including 80 single nucleotide polymorphisms and eight Indel with specific marker sequence index. Among these, the genes with strong correlation were carboxyesterase 1 (CES1) and mucin (MUC) 5B. The CES1 gene loci c.248C>T (p.Ser83Leu) heterozygous mutations, MUC5B gene loci c.6635C>T (p.Thr2212Met) and c.7685C>T (p.Thr2562Met) heterozygous mutations in patients with methyl acetate poisoning were detected. They were missense mutations. By constructing a protein-protein interaction network, a total of 11 pairs of interactions with high levels of evidence were identified, involving genes such as lysine methyltransferase 2C, HECT and RLD domains containing E3 ubiquitin protein ligase 2, neutrophil cytoplasmic factor 1, nicotinamide adenine dinucleotide phosphate oxidase 3, C-terminal binding protein 2, zinc finger protein 717, FSHD region gene 2 family member C, FSHD region gene 1, MUC4, MUC6, MUC5B, and MUC12. Conclusion The polymorphism of CES1 and MUC5B genes may be related to the occurrence and development of methyl acetate poisoning in patients.

Applications of genetic code expansion in the study of lysine acylation / 中国药科大学学报

@#Lysine acylation is a ubiquitous protein modification that controls various aspects of protein function. However, it can be challenging to decipher the biological function of site-specific acylation modifications in living cells.The recently developed genetic code expansion (GCE) technology has enabled site-specific incorporation of unnatural amino acids (UAAs) that are structurally consistent with the natural acylation modifications in vivo through orthogonal aminoacyl-tRNA synthetase/tRNA pairs, thus facilitating the study of physicochemical properties and biological behaviors of homogeneously acylated proteins.Besides, GCE technology allows for the targeted introduction of UAAs that mimic acylation modifications but cannot be recognized by deacylases, which improves the stability of lysine acylation modification products.Moreover, the insertion of photo-crosslinked UAAs at specific sites of the target protein has been used to elucidate the reciprocal proteome of acylated modified proteins.Based on the introduction of different structural and functional acylation modifications, we described the novel design of GCE technology combined with three types of UAAs, and their application in studying the functional effects of protein acylation modifications on the enzyme activity, protein stability, cellular localization, protein-DNA interactions and protein-protein interactions of target proteins, with a description of the limitations and prospects of GCE technology in studying protein acylation modification.

Label-free target identification for natural products based on proteomics / 药学学报

Target identification and verification of natural products is an important and challenging work in the field of chemical biology. It is also an important job for researchers to apply chemical proteomics technology to biomedicine in order to identify target proteins of natural products. Target identification is critical to understanding its mechanisms and developing natural products as molecular probes and potential therapeutic drugs. Traditional approaches of small molecule target identification based on affinity have been shown to be successful, such as click-chemical probes, radioisotope labeling or photosensitized small-molecule probes. Nevertheless, these technologies require purified candidate target proteins, and modified small molecules with probes or linkers, such as adding agarose beads, biotin labels, fluorescent labeling or photo-affinity labeling. Many structure-activity relationship studies should be performed to ensure that the addition of small molecule labels undisturbed the original biological activity of the small molecules. Unfortunately, all these modifications are likely to alter their biological activity or binding specificity. To overcome the bottleneck of "target recognition", researchers have developed a series of new techniques for unmodified drug target identification. In this article, we reviewed the target identification techniques of natural product without structural modification in order to provide reference for the development of natural products.

Mechanism of HES1 regulating herceptin resistance in gastric cancer cells by ferroptosis / 药学学报

Drug resistance of cancer cells is the main causes of chemotherapy failure, and gene mutation or function loss is key factor to induce drug resistance. Previous studies have shown that hairy and enhancer of split 1 (HES1) is up-regulated in herceptin-resistant gastric cancer cells, and inhibition of its activity can reverse its resistance while the potential mechanism has not yet been elucidated. In this study, we employed CRISPR/Cas9 to establish HES1 knock-out cell line (△HES1/NCI N87R) to investigate the functions of HES1 in herceptin resistance of NCI N87R cells and its potential mechanisms. We investigated proteomics profiling of △HES1/NCI N87R cells based on quantitative proteomics. Gene ontology analysis was conducted by GeneSet Enrichment Analysis (GSEA) and Metascape database, and pathway enrichment analysis was done using GeneAnalytics database. The selected molecules were quantified by Western blot and some pathways were verified by using inhibitors. The results showed that the resistance to herceptin of △HES1/NCI N87R cells decreased compared to NCI N87R cells. Proteomic data demonstrated that the expression of 1 263 genes changed significantly in △HES1/NCI N87R cells, among which 761 genes were up-regulated while 502 ones down-regulated comparing with NCI N87R cells. Pathway analysis showed that ferroptosis, fatty acid β-oxidation, autophagy and glutathione metabolism, etc. exhibited notable changes in △HES1/NCI N87R cells. The functional studies showed that the levels of iron ion and malondialdehyde increased, and glutathione decreased in △HES1/NCI N87R cells. It was further found that Fer-1, a ferroptosis inhibitor, could reverse the expression of pTP53, solute carrier family 7 member 11 (SLC7A11) and glutathione peroxidase 4 (GPX4) in △HES1/NCI N87R cell, and reduce the sensitivity of △HES1/NCI N87R cells to herceptin. It is suggested that HES1 regulated the resistance of NCI N87R cells to herceptin through TP53/SLC7A11/GPX4 signaling pathway, and targeting TP53/SLC7A11/GPX4 signal axis mediated by HES1 is a potential strategy to reverse herceptin resistance in gastric cancer.

Synthesis, evaluation and proteomic analysis of PROTAC based on parthenolide / 药学学报

As a natural product with a long history of medicinal use, parthenolide has aroused great interest of chemists and biologists. Existing studies have shown that it has anti-inflammatory, antitumor and other pharmacological activities, and also revealed its action on NF-κB signaling pathway, DNMT1 enzyme and Wnt/β-catenin signaling pathway. But its biological targets remain to be elucidated systematically. Proteolysis Targeting Chimeras (PROTAC) provides a new strategy for target discovery of natural products, which can be used to explore the panorama of protein changes in cells through proteomic investigation, so as to analyze their potential targets. Based on this idea, current study designed and synthesized 20 parthenolide-derived degraders. After measured their antitumor activity in vitro, selected compounds were carried out the proteomic experiment. Finally, 139 down-regulated differentially expressed proteins were identified and the discovery of parthenolide interacting protein was preliminarily explored.

Advances in histone epigenetic enzyme inhibitors based on proteomics / 药学学报

As an important component of nucleosomes on the chromatin of eukaryotic cells, histones play an important role in the development and progression of tumour diseases by regulating epigenetic post-translational modifications such as acetylation and methylation. In addition, development of inhibitors targeting methyltransferase and deacetylase provides novel therapeutic strategies for cancer treatment. Mass spectrometry-based proteomics can reveal the global changes of histone modifications under the action of drugs during disease progression, which in turn provides important support for revealing drug action mechanism, drug resistance mechanism, and investigating novel drug combination strategies. This article focuses on the progress and status of proteomic research on a variety of histone modifying enzyme inhibitors, including methyltransferase inhibitors and histone deacetylase inhibitors, which will help to understand the current and further utilization of proteomics in studying histone modifications.

Mining Novel Anti-Nocardia Drug Targets Based on Pan-genomics and Subtractive Proteomics / 中山大学学报(医学科学版)

ObjectiveNocardia is an apathogen that causes opportunistic infections in humans and has a global distribution. In recent years， resistance of Nocardia to commonly used drugs have been observed， highlighting the urgent need for the identification of new drug targets and the development of novel antimicrobial agents against Nocardia. MethodsThirty-one complete genome sequences of Nocardia strains were retrieved from the GenBank database. Pan-genomic analysis was performed using BPGA， and drug target candidates were screened using subtractive proteomics. Homology modeling was employed to predict the 3D structures of target proteins， and potential drugs targeting these proteins were predicted using DrugBank. Molecular docking techniques were utilized to validate the binding activity between the drugs and target proteins. ResultsThe pan-genomic analysis of the 31 Nocardia strains revealed 1 421 core proteins. Fifteen candidate drug target proteins were identified through subtractive proteomics analysis. Among them， the physicochemical properties of the OG1493 protein （such as amino acid count， molecular weight， isoelectric point， grand average of hydropathicity， fat index，and instability index Ⅱ） were found to be most suitable for a drug target protein. Using the DrugBank database， seven compounds， namely Adenosine-5'-Rp-Alpha-Thio-Triphosphate， alpha，beta-Methyleneadenosine 5'-triphosphate， Phosphoaminophosphonic Acid-Adenylate Ester ，Radicicol，2-Hydroxyestradiol， p-Coumaric acid， and Ethylmercurithiosalicylic acid were identified as potential compounds capable of exerting anti-Nocardia effects by targeting this protein. Molecular docking results indicated a strong binding affinity between the target protein and these compounds. The experimental result showed that that Radicicol could be a potential antibacterial drug targeting this particular protein. ConclusionPan-genomic analysis and subtractive proteomics are valuable approaches for mining novel anti-Nocardia drug targets.