[Identification of the binding proteins of organic acid metabolites by matrix thermal shift assay].

Organic acid metabolites exhibit acidic properties. These metabolites serve as intermediates in major carbon metabolic pathways and are involved in several biochemical pathways, including the tricarboxylic acid (TCA) cycle and glycolysis. They also regulate cellular activity and play crucial roles in epigenetics, tumorigenesis, and cellular signal transduction. Knowledge of the binding proteins of organic acid metabolites is crucial for understanding their biological functions. However, identifying the binding proteins of these metabolites has long been a challenging task owing to the transient and weak nature of their interactions. Moreover, traditional methods are unsuitable for the structural modification of the ligands of organic acid metabolites because these metabolites have simple and similar structures. Even minor structural modifications can significantly affect protein interactions. Thermal proteome profiling (TPP) provides a promising avenue for identifying binding proteins without the need for structural modifications. This approach has been successfully applied to the identification of the binding proteins of several metabolites. In this study, we investigated the binding proteins of two TCA cycle intermediates, i.e., succinate and fumarate, and lactate, an end-product of glycolysis, using the matrix thermal shift assay (mTSA) technique. This technique involves combining single-temperature (52 ℃) TPP and dose-response curve analysis to identify ligand-binding proteins with high levels of confidence and determine the binding affinity between ligands and proteins. To this end, HeLa cells were lysed, followed by protein desalting to remove endogenous metabolites from the cell lysates. The desalted cell lysates were treated with fumarate or succinate at final concentrations of 0.004, 0.04, 0.4, and 2 mmol/L in the experimental groups or 2 mmol/L sodium chloride in the control group. Considering that the cellular concentration of lactate can be as high as 2-30 mmol/L, we then applied lactate at final concentrations of 0.2, 1, 5, 10, and 25 mmol/L in the experimental groups or 25 mmol/L sodium chloride in the control group. Using high-sensitivity mass spectrometry coupled with data-independent acquisition (DIA) quantification, we quantified 5870, 5744, and 5816 proteins in succinate, fumarate, and lactate mTSA experiments, respectively. By setting stringent cut-off values (i.e., significance of changes in protein thermal stability (p-value)<0.001 and quality of the dose-response curve fitting (square of Pearson's correlation coefficient, R2)>0.95), multiple binding proteins for these organic acid metabolites from background proteins were confidently determined. Several known binding proteins were identified, notably fumarate hydratase (FH) as a binding protein for fumarate, and α-ketoglutarate-dependent dioxygenase (FTO) as a binding protein for both fumarate and succinate. Additionally, the affinity data for the interactions between these metabolites and their binding proteins were obtained, which closely matched those reported in the literature. Interestingly, ornithine aminotransferase (OAT), which is involved in amino acid biosynthesis, and 3-mercaptopyruvate sulfurtransferase (MPST), which acts as an antioxidant in cells, were identified as lactate-binding proteins. Subsequently, an orthogonal assay technique developed in our laboratory, the solvent-induced precipitation (SIP) technique, was used to validate the mTSA results. SIP identified OAT as the top target candidate, validating the mTSA-based finding that OAT is a novel lactate-binding protein. Although MPST was not identified as a lactate-binding protein by SIP, statistical analysis of MPST in the mTSA experiments with 10 or 25 mmol/L lactate revealed that MPST is a lactate-binding protein with a high level of confidence. Peptide-level empirical Bayes t-tests combined with Fisher's exact test also supported the conclusion that MPST is a lactate-binding protein. Lactate is structurally similar to pyruvate, the known binding protein of MPST. Therefore, assuming that lactate could potentially occupy the binding site of pyruvate on MPST. Overall, the novel binding proteins identified for lactate suggest their potential involvement in amino acid synthesis and redox balance regulation.

Histatin 5-Inspired Short-Chain Peptides Selectively Combating Pathogenic Fungi with Multifaceted Mechanisms.

Short-chain antifungal peptides (AFPs) inspired by histatin 5 have been designed to address the problem of antifungal drug resistance. These AFPs demonstrate remarkable antifungal activity, with a minimal inhibitory concentration as low as 2 µg mL-1. Notably, these AFPs display a strong preference for targeting fungi rather than bacteria and mammalian cells. This is achieved by binding the histidine-rich domains of the AFPs to the Ssa1/2 proteins in the fungal cell wall, as well as the reduced membrane-disrupting activity due to their low amphiphilicity. These peptides disrupt the nucleus and mitochondria once inside the cells, leading to reactive oxygen species production and cell damage. In a mouse model of vulvovaginal candidiasis, the AFPs demonstrate not only antifungal activity, but also promote the growth of beneficial Lactobacillus spp. This research provides valuable insights for the development of fungus-specific AFPs and offers a promising strategy for the treatment of fungal infectious diseases.

Prediction of mortality and overt hepatic encephalopathy undergoing transjugular intrahepatic portosystemic shunt: a retrospective cohort study.

PURPOSE: Data on medium- and long-term efficacy and safety of Transjugular intrahepatic portosystemic shunt (TIPS) using Viatorr stents in Chinese patients are limited. This study aimed to evaluate the 5-year mortality and the incidence of overt hepatic encephalopathy (OHE) after Viatorr stent insertion, and construct a model to predict post-TIPS OHE preoperatively. METHODS: One hundred thirty-two patients undergoing Viatorr stent insertion in our institution between August 2016 and December 2019 were included, and randomly divided into training and validation cohort at a 70/30 ratio. Patients were followed up until death or the end date of follow-up (December 31st, 2021). The primary end point was all-cause mortality, and the secondary end points were OHE, variceal rebleeding, recurrent ascites and shunt dysfunction. RESULTS: The 1-, 2-, 3-, 4- and 5-year cumulative survival rates were 92.4%, 87.9%, 85.3%, 80.2% and 80.2%, respectively. Post-TIPS OHE and Child-Pugh grade were independent prognostic factors. The rates of variceal rebleeding, recurrent ascites, shunt dysfunction and post-TIPS OHE were 9.1%, 14.3%, 5.3% and 28.0%, respectively. The variables of nomogram predicting post-TIPS OHE included age, diabetes and ascites grade. The area under time-dependent receiver operation characteristic (ROC) curve (AUC) in training and validation cohort were 0.806 and 0.751, respectively. The decision curve analysis (DCA) showed good net benefit both in training and validation cohort. CONCLUSION: Post-TIPS OHE and Child-Pugh grade are independent prognostic factors for early mortality in cirrhosis patients, thus we construct a simple and convenient prediction model for post-TIPS OHE to identify high-risk patients preoperatively.

The Introduction of Detergents in Thermal Proteome Profiling Requires Lowering the Applied Temperatures for Efficient Target Protein Identification.

Although the use of detergents in thermal proteome profiling (TPP) has become a common practice to identify membrane protein targets in complex biological samples, surprisingly, there is no proteome-wide investigation into the impacts of detergent introduction on the target identification performance of TPP. In this study, we assessed the target identification performance of TPP in the presence of a commonly used non-ionic detergent or a zwitterionic detergent using a pan-kinase inhibitor staurosporine, our results showed that the addition of either of these detergents significantly impaired the identification performance of TPP at the optimal temperature for soluble target protein identification. Further investigation showed that detergents destabilized the proteome and increased protein precipitation. By lowering the applied temperature point, the target identification performance of TPP with detergents is significantly improved and is comparable to that in the absence of detergents. Our findings provide valuable insight into how to select the appropriate temperature range when detergents are used in TPP. In addition, our results also suggest that the combination of detergent and heat may serve as a novel precipitation-inducing force that can be applied for target protein identification.

Surface decoration with leucine tetrapeptide: An antibacterial strategy against Gram-negative bacteria.

Surface-associated microbe contamination by Gram-negative bacteria poses a serious problem in medical care. Cationic peptides or polymers are the main materials used for antibacterial surface coating, but the positive charge may lead to blood coagulation. Therefore, exploiting surface coating which is free of positive charge and is effective for Gram-negative bacteria inactivation is in urgent need. In this study, inspired by the affinity between lipopolysaccharides of Gram-negative bacteria and Toll-like receptors of immune cells, we develop a leucine-based tetrapeptide coating strategy for combating Gram-negative bacteria. The obtained surface has excellent bactericidal activity against Gram-negative bacteria like Pseudomonas aeruginosa and Escherichia coli. A 1 mm2 coated glass surface could kill > 9.9 × 104 CFU bacteria in 1 h and has nearly no damage to mammal cells. Moreover, this surface coating strategy could be applied on various surfaces like glass slices, glass capillary cavity and thermoplastic polyurethane slices. And the coated surface could largely mitigate the microbe contamination in an in vivo subcutaneous implantation. This work paves a new way for antibacterial surface-coating which is behaving no positive charge and is of great importance for biomedical devices.

Efficacy of Mesenchymal Stem Cell Therapy on Lupus Nephritis and Renal Function in Systemic Lupus Erythematosus: A Meta-Analysis.

PURPOSE: The purpose of this meta-analysis is to determine the efficacy of mesenchymal stromal/stem cell (MSC) transplantation therapy on lupus nephritis (LN) and renal function of patients with systemic lupus erythematosus (SLE). METHODS: Articles that reported the data of MSC therapy on the renal function as well as disease activity of LN in patients with SLE were searched in PubMed, Web of Science, Embase and the Cochrane Library. Mean difference for disease activity and laboratory parameters were pooled to evaluate the efficacy of MSC, and incidence was pooled for clinical remission, death and severe adverse event. RESULTS: A total of 12 studies with 586 patients were included. The disease activity indices, including SLEDAI and BILAG, were significantly decreased within 12 months after MSC therapy (P< 0.05). Laboratory parameters for renal function and disease control including estimated glomerular filtration rate, creatinine, blood urea nitrogen, complement C3, albumin and urine protein, were also significantly improved after therapy. The pooled rate of clinical remission at 12 months was 28.1% and the total rate during follow-up was 33.7%. The pooled rate of death at 12 months was 5.2% and the total rate during follow-up was 5.5%. Severe adverse events were rare and not associated with the treatment of MSC. CONCLUSIONS: This is the first meta-analysis that focuses on the effect of MSC on LN and renal function of patients with SLE, and the results shows a favorable safety profile and encouraging results of MSC for improving the disease activity of LN as well as the renal function of SLE patients.

One-Dimensional Rod-like Tobacco Mosaic Virus Promotes Macrophage Polarization for a Tumor-Suppressive Microenvironment.

The phenotype of tumor-associated macrophages plays an important role in their function of regulating the tumor immune microenvironment. The M1-phenotype macrophages display tumor-killing and immune activating functions. Here we show that the tobacco mosaic virus (TMV), a rod-like plant virus, can polarize macrophages to an M1 phenotype and shape a tumor-suppressive microenvironment. RAW 264.7 cells and bone marrow derived-macrophages (BMDMs) can recognize TMV via Toll-like receptor-4, and then the MAPK and NF-κB signaling pathways are activated, leading to the production of pro-inflammatory factors. Furthermore, the in vivo assessments on a subcutaneous co-injection tumor model show that the TMV-polarized BMDMs shape a tumor-suppressive microenvironment, resulting in remarkable delay of 4T1 tumor growth. Another in vivo assessment on an established tumor model indicates the high tumor-metastasis-inhibiting capacity of TMV-polarized BMDMs. This work suggests a role for this plant virus in macrophage-mediated therapeutic approaches and provides a strategy for tumor immunotherapy.

Extracellular HSP90 promotes differentiation of lens epithelial cells to fiber cells by activating LRP1-YAP-PROX1 axis.

Capsular residual lens epithelial cells (CRLEC) undergo differentiation to fiber cells for lens regeneration or tansdifferentiation to myofibroblasts leading to posterior capsular opacification (PCO) after cataract surgery. The underlying regulatory mechanism remains unclear. Using human lens epithelial cell lines and the ex vivo cultured rat lens capsular bag model, we found that the lens epithelial cells secrete HSP90α extracellularly (eHSP90) through an autophagy-associated pathway. Administration of recombinant GST-HSP90α protein or its M-domain induces the elongation of rat CRLEC cells with concomitant upregulation of the crucial fiber cell transcriptional factor PROX1and its downstream targets, ß- and γ-crystallins and structure proteins. This regulation is abolished by PROX1 siRNA. GST-HSP90α upregulates PROX1 by binding to LRP1 and activating LRP1-AKT mediated YAP degradation. The upregulation of GST-HSP90α on PROX1 expression and CRLEC cell elongation is inhibited by LRP1 and AKT inhibitors, but activated by YAP-1 inhibitor (VP). These data demonstrated that the capsular residue epithelial cells upregulate and secrete eHSP90α, which in turn drive the differentiation of lens epithelial cell to fiber cells. The recombinant HSP90α protein is a potential novel differentiation regulator during lens regeneration.

Efficacy and safety of laparoscopic common bile duct exploration with primary closure and intraoperative endoscopic nasobiliary drainage for choledocholithiasis combined with cholecystolithiasis.

BACKGROUND: The need for intraoperative endoscopic nasobiliary drainage during laparoscopic cholecystectomy and laparoscopic common bile duct exploration with primary closure is controversial in the treatment of cholecystolithiasis combined with choledocholithiasis. The aim of this study was to evaluate the safety and efficacy of laparoscopic cholecystectomy + laparoscopic common bile duct exploration + intraoperative endoscopic nasobiliary drainage + primary closure (LC + LCBDE + IO-ENBD + PC). The safety of different intubation methods in IO-ENBD was also evaluated. METHOD: From January 2018 to January 2022, 168 consecutive patients with cholecystolithiasis combined with choledocholithiasis underwent surgical treatment in our institution. Patients were divided into two groups: group A (n = 96) underwent LC + LCBDE + IO-ENBD + PC and group B (n = 72) underwent LC + LCBDE + PC. Patient characteristics, perioperative indicators, complications, stone residual, and recurrence rates were analyzed. Group A was divided into two subgroups. In group A1, the nasobiliary drainage tube was placed in an anterograde way, and in group A2, nasobiliary drainage tube was placed in an anterograde-retrograde way. Perioperative indicators and complications were analyzed between subgroups. RESULTS: No mortality in the two groups. The operation success rates in groups A and B were 97.9% (94/96) and 100% (72/72), respectively. In group A, two patients were converted to T-tube drainage. The stone clearance rates of group A and group B were 100% (96/96) and 98.6% (71/72), respectively. Common bile duct diameter was smaller in group A [10 vs. 12 mm, P < 0.001] in baseline data. In perioperative indicators, group A had a longer operation time [165 vs.135 min, P < 0.001], but group A had a shorter hospitalization time [10 vs.13 days, P = 0.002]. The overall complications were 7.3% (7/96) in group A and 12.5% (9/72) in group B. Postoperative bile leakage was less in group A [0% (0/96) vs. 5.6% (4/72), P = 0.032)]. There were no residual and recurrent stones in group A. And there were one residual stone and one recurrent stone in group B (all 1.4%). The median follow-up time was 12 months in group A and 6 months in group B. During the follow-up period, 2 (2.8%) patients in group B had a mild biliary stricture. At subgroup analysis, group A1 had shorter operation time [150 vs. 182.5 min, P < 0.001], shorter hospitalization time [9 vs. 10 days, P = 0.002], and fewer patients with postoperative elevated pancreatic enzymes [32.6% (15/46) vs. 68% (34/50), P = 0.001]. CONCLUSION: LC + LCBDE + IO-ENBD + PC is safer and more effective than LC + LCBDE + PC because it reduces hospitalization time and avoids postoperative bile leakage. In the IO-ENBD procedure, the antegrade placement of the nasobiliary drainage tube is more feasible and effective because it reduces the operation time and hospitalization time, and also reduces injury to the duodenal papilla.

Highly effective identification of drug targets at the proteome level by pH-dependent protein precipitation.

Fully understanding the target spaces of drugs is essential for investigating the mechanism of drug action and side effects, as well as for drug discovery and repurposing. In this study, we present an energetics-based approach, termed pH-dependent protein precipitation (pHDPP), to probe the ligand-induced protein stability shift for proteome-wide drug target identification. We demonstrate that pHDPP works for a diverse array of ligands, including a folate derivative, an ATP analog, a CDK inhibitor and an immunosuppressant, enabling highly specific identification of target proteins from total cell lysates. This approach is compared to thermal and solvent-induced denaturation approaches with a pan-kinase inhibitor as the model drug, demonstrating its high sensitivity and high complementarity to other approaches. Dihydroartemisinin (DHA), a dominant derivative of artemisinin to treat malaria, is known to have an extraordinary effect on the treatment of various cancers. However, the anti-tumor mechanisms remain unknown. pHDPP was applied to reveal the target space of DHA and 45 potential target proteins were identified. Pathway analysis indicated that these target proteins were mainly involved in metabolism and apoptosis pathways. Two cancer-related target proteins, ALDH7A1 and HMGB1, were validated by structural simulation and AI-based target prediction methods. And they were further validated to have strong affinity to DHA by using cellular thermal shift assay (CETSA). In summary, pHDPP is a powerful tool to construct the target protein space to reveal the mechanism of drug action and would have broad application in drug discovery studies.

Proteome-Wide Deconvolution of Drug Targets and Binding Sites by Lysine Reactivity Profiling.

Recently, numerous efforts have been devoted to identifying drug targets and binding sites in complex proteomes, which is of great importance in modern drug discovery. In this study, we developed a robust lysine reactivity profiling method to systematically study drug-binding targets and binding sites at the proteome level. This method is based on the principle that binding of a drug to a specific region of target proteins will change the reactivity of lysine residues that are located at this region, and these changes can be detected with an enrichable and lysine reactive probe. Coupled with data-independent acquisition (DIA), the known target proteins and corresponding binding sites were successfully revealed from K562 cell lysates for three model drugs: geldanamycin, staurosporine, and dasatinib. In addition, the drug-induced conformational changes of certain targets were also revealed by our method during the screening of staurosporine. The screening sensitivity of our method revealed from the screening of stuarosporine and dasatinib was comparable with that of thermal proteome profiling (TPP) or machine learning-based limited proteolysis (LiP-Quant). Overall, 21 and 4 kinase targets, including adenosine 5'-triphosphate (ATP)-binding targets, were identified for staurosporine and dasatinib in K562 cell lysates, respectively. We found that target proteins identified by TPP, LiP-Quant, and our method were complementary, emphasizing that the development of new methods that probe different properties of proteins is of great importance in drug target deconvolution. We also envision further applications of our method in proteome-wide probing multiple events that involve lysine reactivity changes.

Nanosecond pulsed electric fields prime mesenchymal stem cells to peptide ghrelin and enhance chondrogenesis and osteochondral defect repair in vivo.

Mesenchymal stem cells (MSCs) are important cell sources in cartilage tissue development and homeostasis, and multiple strategies have been developed to improve MSCs chondrogenic differentiation with an aim of promoting cartilage regeneration. Here we report the effects of combining nanosecond pulsed electric fields (nsPEFs) followed by treatment with ghrelin (a hormone that stimulates release of growth hormone) to regulate chondrogenesis of MSCs. nsPEFs and ghrelin were observed to separately enhance the chondrogenesis of MSCs, and the effects were significantly enhanced when the bioelectric stimulation and hormone were combined, which in turn improved osteochondral tissue repair of these cells within Sprague Dawley rats. We further found that nsPEFs can prime MSCs to be more receptive to subsequent stimuli of differentiation by upregulated Oct4/Nanog and activated JNK signaling pathway. Ghrelin initiated chondrogenic differentiation by activation of ERK1/2 signaling pathway, and RNA-seq results indicated 243 genes were regulated, and JAK-STAT signaling pathway was involved. Interestingly, the sequential order of applying these two stimuli is critical, with nsPEFs pretreatment followed by ghrelin enhanced chondrogenesis of MSCs in vitro and subsequent cartilage regeneration in vivo, but not vice versa. This synergistic prochondrogenic effects provide us new insights and strategies for future cell-based therapies.

Value of multidisciplinary team (MDT) in minimally invasive treatment of complex intrahepatic bile duct stones.

This study aimed to investigate the value of multidisciplinary team (MDT) management in minimally invasive treatment of complex intrahepatic bile duct stones (IHDs) by laparoscopy, choledochoscopy and percutaneous choledochoscopy. The characteristics, perioperative index, complication rate and minimally invasive rate of patients in MDT group (n = 75) and non-MDT group (n = 70) were compared. The members of MDT include doctors in ultrasound, imaging, hepatobiliary and pancreatic surgery, anaesthesia and intensive care medicine. The results showed that minimally invasive surgery reduced the incidence of postoperative residual stones, OR (95% CI) = 0.365 (0.141-0.940) (p = 0.037). MDT reduced the operation time, OR (95% CI) = 0.406 (0.207-0.796) (p = 0.009). Minimally invasive surgery significantly reduced intraoperative bleeding, OR (95% CI) = 0.267 (0.133-0.534) (p < 0.001). Minimally invasive surgery also reduced hospitalization time, OR (95% CI) = 0.295 (0.142-0.611) (p = 0.001). The stone clearance rates of MDT group and non-MDT group were 81.33% and 81.43% respectively. In the MDT group, the operative time was less than that in the non-MDT group (p = 0.010); the intraoperative bleeding volume was significantly less than that in the non-MDT group (p < 0.001); the hospitalization time was less than that in the non-MDT group (p = 0.001). Minimally invasive operation rate:48 cases (64.00%) in MDT group were significantly higher than 17 cases (24.29%) in non-MDT group (p < 0.001). In conclusion, minimally invasive procedures can be selected more through MDT. MDT can shorten the operation time, and minimally invasive surgery can reduce the incidence of residual stones, reduce intraoperative bleeding, and may shorten hospital stay. Therefore, MDT management model can provide personalized and minimally invasive surgical protocol for patients with complex IHD, which has high application value.

High expression of PARD3 predicts poor prognosis in hepatocellular carcinoma.

Hepatocellular carcinoma (HCC) is one of the most commonly cancers with poor prognosis and drug response. Identifying accurate therapeutic targets would facilitate precision treatment and prolong survival for HCC. In this study, we analyzed liver hepatocellular carcinoma (LIHC) RNA sequencing (RNA-seq) data from The Cancer Genome Atlas (TCGA), and identified PARD3 as one of the most significantly differentially expressed genes (DEGs). Then, we investigated the relationship between PARD3 and outcomes of HCC, and assessed predictive capacity. Moreover, we performed functional enrichment and immune infiltration analysis to evaluate functional networks related to PARD3 in HCC and explore its role in tumor immunity. PARD3 expression levels in 371 HCC tissues were dramatically higher than those in 50 paired adjacent liver tissues (p < 0.001). High PARD3 expression was associated with poor clinicopathologic feathers, such as advanced pathologic stage (p = 0.002), vascular invasion (p = 0.012) and TP53 mutation (p = 0.009). Elevated PARD3 expression also correlated with lower overall survival (OS, HR = 2.08, 95% CI = 1.45-2.98, p < 0.001) and disease-specific survival (DSS, HR = 2.00, 95% CI = 1.27-3.16, p = 0.003). 242 up-regulated and 71 down-regulated genes showed significant association with PARD3 expression, which were involved in genomic instability, response to metal ions, and metabolisms. PARD3 is involved in diverse immune infiltration levels in HCC, especially negatively related to dendritic cells (DCs), cytotoxic cells, and plasmacytoid dendritic cells (pDCs). Altogether, PARD3 could be a potential prognostic biomarker and therapeutic target of HCC.

Elevated Circulating Fetuin-B Levels Are Associated with Insulin Resistance and Reduced by GLP-1RA in Newly Diagnosed PCOS Women.

BACKGROUND: Previous studies have suggested that Fetuin-B seems to be a secreted adipokine related to metabolic diseases. However, the results have been inconsistent. Here, our objective is to investigate the changes in circulating Fetuin-B levels in women with polycystic ovary syndrome (PCOS) and analyze the association of Fetuin-B and insulin resistance (IR). METHODS: The current study is comprised of a cross-sectional study and a series of interventional studies. Oral glucose tolerance test (OGTT) and euglycemic-hyperinsulinemic clamp (EHC) were engaged to assess glucose tolerance and insulin sensitivity. Serum Fetuin-B levels were determined by ELISA. RESULTS: Serum Fetuin-B and TNF-α levels were markedly increased in women with PCOS compared to healthy women. Circulating Fetuin-B was positively associated with body mass index, waist-to-hip ratio, the percentage of body fat (FAT%), systolic blood pressure, triglyceride, low-density lipoprotein cholesterol, fasting blood glucose, 2 h blood glucose after glucose overload, fasting insulin, 2 h insulin after glucose overload, HOMA-insulin resistance index (HOMA-IR), the area under the curve for insulin (AUCi), AUCg, and TNF-α, while negatively associated with M value and follicular stimulating hormone (FSH). During the EHC, Fetuin-B levels were found to be significantly increased in PCOS women. After a glucose challenge, serum Fetuin-B levels in healthy women were significantly increased. Lipid infusion reduced serum Fetuin-B levels in 30 healthy subjects. After six months of glucagon-like peptide-1 receptor agonist (GLP-1RA) intervention, serum Fetuin-B concentrations in PCOS women markedly decreased following ameliorated IR. CONCLUSION: Our results indicate that Fetuin-B may be a biomarker of IR in individuals with PCOS. This trial is registered with ChiCTR-IIR-16007901.

Microparticle-Assisted Precipitation Screening Method for Robust Drug Target Identification.

While thermal proteome profiling (TPP) shines in the field of drug target screening by analyzing the soluble fraction of the proteome samples treated at high temperature, the counterpart, the insoluble precipitate, has been overlooked for a long time. The analysis of the precipitate is hampered by the inefficient sample processing procedure. Herein, we propose a novel method, termed microparticle-assisted precipitation screening (MAPS), for drug target identification. The MAPS method exploits the principle that drug-bound proteins will be more resistant to thermal unfolding similar to the classic TPP method, but the process of protein precipitation is assisted by microparticles. Upon heating, proteins unfold and aggregate on the surface of the microparticles. The introduction of a microparticle simplifies the whole sample preparation workflow. The proteins that precipitate on the microparticles are subjected to washing, alkylation, and digestion. The whole sample preparation is processed conveniently on the surface of the microparticles without any transfer. With the assistance of microparticles, sample loss is minimized. The MAPS method is compatible with minute amounts of initial proteins. MAPS was applied to screen the targets of several well-studied drugs and the known target proteins were successfully identified with high confidence and specificity. To investigate the specificity of the method, MAPS was applied to screen the targets of the pan-kinase inhibitor, staurosporine, and 32 protein kinases (specificity of 80%) were identified using only 20 µg of initial proteins of each sample. MAPS is an unbiased robust method for drug target screening, filling the vacancy of stability-based target screening using a precipitate.

Nitidine chloride efficiently induces autophagy and apoptosis in melanoma cells via AMPK-mTOR signaling pathway.

Nitidine chloride (NC) has displayed anti-tumor effects in various types of cancer. However, the role of NC in human melanoma is largely unknown. This study aimed to investigate the effects of NC on melanoma cancer cells A375 and WM35 by MTT assay. Apoptosis was measured by detecting caspase-3 protein expression level and its activity. Autophagy was measured by TEM image, immunostaining and immunoblotting assays. MTT assays showed that NC significantly blocks melanoma cells proliferation. Immunoblotting and caspase-3 activity assays showed that NC inhibited melanoma cells proliferation by inducing cell apoptosis. TEM, immunostaining and immunoblotting assays showed that NC also triggers melanoma cells autophagy and activation of the AMPK-mTOR pathway, which plays an important role in autophagy initiation. Finally, we found that blocking autophagy by 3-MA or AMPK pathway inhibitor greatly enhanced NC-induced apoptosis and cell death, indicating that NC-induced autophagy may have a cytoprotective effect in melanoma cells. Together, these results suggested that NC has strong anti-tumor effects on melanoma cells.

Nanosecond pulsed electric fields enhance mesenchymal stem cells differentiation via DNMT1-regulated OCT4/NANOG gene expression.

BACKGROUND: Multiple strategies have been proposed to promote the differentiation potential of mesenchymal stem cells (MSCs), which is the fundamental property in tissue formation and regeneration. However, these strategies are relatively inefficient that limit the application. In this study, we reported a novel and efficient strategy, nanosecond pulsed electric fields (nsPEFs) stimulation, which can enhance the trilineage differentiation potential of MSCs, and further explained the mechanism behind. METHODS: We used histological staining to screen out the nsPEFs parameters that promoted the trilineage differentiation potential of MSCs, and further proved the effect of nsPEFs by detecting the functional genes. In order to explore the corresponding mechanism, we examined the expression of pluripotency genes and the methylation status of their promoters. Finally, we targeted the DNA methyltransferase which was affected by nsPEFs. RESULTS: The trilineage differentiation of bone marrow-derived MSCs was significantly enhanced in vitro by simply pre-treating with 5 pulses of nsPEFs stimulation (energy levels as 10 ns, 20 kV/cm; 100 ns, 10 kV/cm), due to that the nsPEFs demethylated the promoters of stem cell pluripotency genes OCT4 and NANOG through instantaneous downregulation of DNA methylation transferase 1 (DNMT1), thereby increasing the expression of OCT4 and NANOG for up to 3 days, and created a treatment window period of stem cells. CONCLUSIONS: In summary, nsPEFs can enhance MSCs differentiation via the epigenetic regulation and could be a safe and effective strategy for future stem cell application.

A Simplified Thermal Proteome Profiling Approach to Screen Protein Targets of a Ligand.

Thermal proteome profiling is a powerful energetic-based chemical proteomics method to reveal the ligand-protein interaction. However, the costly multiplexed isotopic labeling reagent, mainly Multiplexed isobaric tandem mass tag (TMT), and the long mass spectrometric time limits the wide application of this method. Here a simple and cost-effective strategy by using dimethyl labeling technique instead of TMT labeling is reported to quantify proteins and by using the peptides derived from the same protein to determine significantly changed proteins in one LC-MS run. This method is validated by identifying the known targets of methotrexate and geldanamycin. In addition, several potential off-targets involved in detoxification of reactive oxygen species pathway are also discovered for geldanamycin. This method is further applied to map the interactome of adenosine triphosphate (ATP) in the 293T cell lysate by using ATP analogue, adenylyl imidodiphosphate (AMP-PNP), as the ligand. As a result, a total of 123 AMP-PNP-sensitive proteins are found, of which 59 proteins are stabilized by AMP-PNP. Approximately 53% and 20% of these stabilized candidate protein targets are known as ATP and RNA binding proteins. Overall, above results demonstrated that this approach could be a valuable platform for the unbiased target proteins identification with reduced reagent cost and mass spectrometric time.