Modifiable lifestyle factors influencing psychiatric disorders mediated by plasma proteins: A systemic Mendelian randomization study

BACKGROUND

Psychiatric disorders are emerging as a serious public health hazard, influencing an increasing number of individuals worldwide. However, the effect of modifiable lifestyle factors on psychiatric disorders remains unclear.

METHODS

Genome-wide association studies (GWAS) summary statistics were obtained mainly from Psychiatric Genomics Consortium and UK Biobank, with sample sizes varying between 10,000 and 1,200,000. The two-sample Mendelian randomization (MR) method was applied to investigate the causal associations between 45 lifestyle factors and 13 psychiatric disorders, and screen potential mediator proteins from 2992 candidate plasma proteins. We implemented a four-step framework with step-by-step screening incorporating two-step, univariable, and multivariable MR.

RESULTS

We found causal effects of strenuous sports or other exercise on Tourette's syndrome (OR [95%CI]: 0.0047 [5.24E-04-0.042]); lifelong smoking index on attention-deficit hyperactivity disorder (10.53 [6.96-15.93]), anxiety disorders (3.44 [1.95-6.05]), bipolar disorder (BD) (2.25 [1.64-3.09]), BD II (2.89 [1.81-4.62]), and major depressive disorder (MDD) (2.47 [1.90-3.20]); and educational years on anorexia nervosa (AN) (1.47 [1.22-1.76]), and MDD (0.74 [0.66-0.83]). Five proteins were found to have causal associations with psychiatric disorders, namely ADH1B, GHDC, STOM, CD226, and TP63. STOM, a membrane protein deficient in the erythrocytes of hereditary stomatocytosis patients, may mediate the effect of educational attainment on AN.

LIMITATIONS

The mechanisms underlying the effects of lifestyle factors on psychiatric disorders require further investigation.

CONCLUSIONS

These findings could help assess the risk of psychiatric disorders based on lifestyle factors and also support lifestyle interventions as a prevention strategy for mental illness.

Haematological, biochemical, enzymological changes and mitochondrial dysfunction of liver in freshwater climbing perch Anabas testudineus during their acute and chronic exposure to sodium fluoride

Anthropogenic activities are increasing fluoride concentration in watercourses. The present study focuses on the sublethal toxicity of sodium fluoride during sub-chronic and chronic time periods in the freshwater fish Anabas testudineus. The 96-hour LC50 value for fluoride was found to be 616.50 mg/L. Excessive mucous production and hyper excitability, followed by loss of balance, were seen in fish under acute fluoride exposure. Significant reduction in yield and specific growth rate of fish were assessed at 15, 30 and 45-days exposure intervals. Different bio-indicators like Hepatosomatic-index, Gonadosomatic-index and fecundity were reduced significantly in fish exposed to 10% (61.6 mg/L) and 20% (123.2 mg/L) of 96 h of LC50 values of fluoride in comparison to control. Toxicant concentrations directly correlated with parameter lowering. Fluoride exposure increased plasma glucose, creatinine, AST, and ALT and reduced total RBC, haemoglobin content, Hct (%), plasma protein, and cholesterol. Moreover, fluoride exposure significantly reduces the mitochondrial membrane potential in liver. This may result in metabolic depression, haematological, biochemical, and enzymological stress. The in-silico structural analysis predicts that fluoride may impede cytochrome c oxidase of the electron transport system, hence inhibiting mitochondrial functionality. These findings collectively highlight the urgent need for stringent regulation and monitoring of fluoride levels in freshwater ecosystems, as the subchronic and chronic effects observed in A. testudineus may have broader implications for aquatic ecosystems.

Protein-centric omics integration analysis identifies candidate plasma proteins for multiple autoimmune diseases

It remains challenging to translate the findings from genome-wide association studies (GWAS) of autoimmune diseases (AIDs) into interventional targets, presumably due to the lack of knowledge on how the GWAS risk variants contribute to AIDs. In addition, current immunomodulatory drugs for AIDs are broad in action rather than disease-specific. We performed a comprehensive protein-centric omics integration analysis to identify AIDs-associated plasma proteins through integrating protein quantitative trait loci datasets of plasma protein (1348 proteins and 7213 individuals) and totally ten large-scale GWAS summary statistics of AIDs under a cutting-edge systematic analytic framework. Specifically, we initially screened out the protein-AID associations using proteome-wide association study (PWAS), followed by enrichment analysis to reveal the underlying biological processes and pathways. Then, we performed both Mendelian randomization (MR) and colocalization analyses to further identify protein-AID pairs with putatively causal relationships. We finally prioritized the potential drug targets for AIDs. A total of 174 protein-AID associations were identified by PWAS. AIDs-associated plasma proteins were significantly enriched in immune-related biological process and pathways, such as inflammatory response (P = 3.96 × 10-10). MR analysis further identified 97 protein-AID pairs with potential causal relationships, among which 21 pairs were highly supported by colocalization analysis (PP.H4 > 0.75), 10 of 21 were the newly discovered pairs and not reported in previous GWAS analyses. Further explorations showed that four proteins (TLR3, FCGR2A, IL23R, TCN1) have corresponding drugs, and 17 proteins have druggability. These findings will help us to further understand the biological mechanism of AIDs and highlight the potential of these proteins to develop as therapeutic targets for AIDs.

Associations of ultra-processed food consumption, circulating protein biomarkers, and risk of cardiovascular disease

BACKGROUND

We aim to examine the association between ultra-processed foods (UPF) consumption and cardiovascular disease (CVD) risk and to identify plasma proteins associated with UPF.

METHODS

This prospective cohort study included 26,369 participants from the Swedish Malmö Diet and Cancer Study, established in 1991-1996. Dietary intake was assessed using a modified diet history method, and UPF consumption was estimated using the NOVA classification system. A total of 88 selected CVD-related proteins were measured among 4475 subjects. Incident CVD (coronary heart disease and ischemic stroke) was defined as a hospital admission or death through registers. Cox proportional hazards regression models were performed to analyze the associations of UPF intake with risks of CVD. Linear regression models were used to identify the plasma proteins associated with UPF intake.

RESULTS

During 24.6 years of median follow-up, 6236 participants developed CVD, of whom 3566 developed coronary heart disease and 3272 developed ischemic stroke. The adjusted hazard ratio (95% confidence interval) in the 4th versus 1st quartile of UPF was 1.18 (1.08, 1.29) for CVD, 1.20 (1.07, 1.35) for coronary heart disease, and 1.17 (1.03, 1.32) for ischemic stroke. Plasma proteins interleukin 18, tumor necrosis factor receptor 2, macrophage colony-stimulating factor 1, thrombomodulin, tumor necrosis factor receptor 1, hepatocyte growth factor, stem cell factor, resistin, C-C motif chemokine 3, and endothelial cell-specific molecule 1 were positively associated with UPF after correcting for multiple testing.

CONCLUSIONS

Our study showed that high UPF intake increased the risk of CVD and was associated with several protein biomarkers. Future studies are warranted to validate these findings and assess the potential pathways between UPF intake and CVD.

Potential use of Cypridina luciferin for quantifying alpha 1-acid glycoprotein in human serum

Alpha 1-acid glycoprotein (AGP) is an acute phase protein in mammals, including humans. The amount of AGP in human serum varies in response to certain diseases; thus, many efforts have been made to develop methods for quantifying human AGP. We recently discovered that luminescence occurs merely by mixing Cypridina luciferin with human AGP under human serum-free neutral or basic buffer conditions. In this study, we tested an application of Cypridina luciferin for quantifying AGP contained in human serum. Our luminescence spectrum measurements of Cypridina luciferin with human serum samples showed that the maximum emission wavelength with human serum (480 nm) differed from that with human AGP (464 nm) due to the abundant presence of endogenous human serum albumin (HSA). Furthermore, the luminescence intensities of Cypridina luciferin with human AGP in HSA-depleted human serum were consistent with those in a human serum-free basic buffer, but those in human serum were not. These results indicated that depletion of HSA in human serum was required to use Cypridina luciferin for quantifying AGP in human serum. Additionally, we found that the luminescence intensity of Cypridina luciferin with bovine AGP was approximately tenfold lower than that with human AGP.

Exploring the genetic relationship between deep vein thrombosis and plasma protein: a new research idea

BACKGROUND

The aim of this article is to scan and analyze the genetic correlation between plasma proteome and deep venous thrombosis(DVT), and to explore the correlation between plasma protein and DVT.

RESEARCH DESIGN AND METHODS

GWAS data of DVT and plasma proteins were analyzed with linkage disequilibrium scores, and plasma proteins that were genetically associated with DVT were screened out. To ascertain the causal link between potential plasma proteins and DVT, a Mendelian randomized (MR) study was used. This study used STRING to examine the pathogenesis of DVT in connection with the gene encoding plasma protein.

RESULTS

Several suggestive plasma proteins were detected for DVT, such as Complement factor B (correlation coefficient =0.3883 P value=0.0177), Chromogranin-A (correlation coefficient =-0.4786, P value=0.0158). Through MR analysis, we found that there was a significant positive causal relationship between Chromogranin-A (exposure) and DVT (outcome) (β=-0.0117, SE=0.0013, P<0.0001). Our STRING analysis revealed that hsa04610 was associated with coagulation cascade in the KEGG pathway of Complement factor B(P<0.0001), which was based on GO and KEGG analysis of 8 selected plasma proteins.

CONCLUSIONS

A genetic link between plasma protein and DVT was thoroughly investigated. Our findings provide a fresh perspective on the genetics and pathogenesis of DVT.

A large-scale genetic correlation scan between rheumatoid arthritis and human plasma protein

Aims

The aim of this study was to explore the genetic correlation and causal relationship between blood plasma proteins and rheumatoid arthritis (RA).

Methods

Based on the genome-wide association studies (GWAS) summary statistics of RA from European descent and the GWAS summary datasets of 3,622 plasma proteins, we explored the relationship between RA and plasma proteins from three aspects. First, linkage disequilibrium score regression (LD score regression) was applied to detect the genetic correlation between RA and plasma proteins. Mendelian randomization (MR) analysis was then used to evaluate the causal association between RA and plasma proteins. Finally, GEO2R was used to screen the differentially expressed genes (DEGs) between patients with RA and healthy controls.

Results

We found that seven kinds of plasma proteins had genetic correlations with RA, such as Soluble Receptor for Advanced Glycation End Products (sRAGE) (correlation coefficient = 0.2582, p = 0.049), vesicle transport protein USE1 (correlation coefficient = 0.1337, p = 0.018), and spermatogenesis-associated protein 20 (correlation coefficient = 0.3706, p = 0.018). There was a significant causal relationship between sRAGE and RA. By comparing the genes encoding seven plasma proteins, we found that only USE1 was a DEG associated with RA.

Conclusion

Our study identified a set of candidate plasma proteins that showed signals correlated with RA. Since the results of this study need further experimental verification, they should be interpreted with caution. However, we hope that this paper will provide new insights for the discovery of pathogenic genes and RA pathogenesis in the future.

Cite this article: Bone Joint Res 2022;11(2):134–142.

Differential responses of weaned piglets to supplemental porcine or chicken plasma in diets without inclusion of antibiotics and zinc oxide

This study was conducted to investigate the effects of spray-dried porcine plasma protein (SDPP) or spray-dried chicken plasma protein (SDCP) supplementation in diets without the inclusion of antibiotics and zinc oxide (ZnO) on growth performance, fecal score, and fecal microbiota in early-weaned piglets. A total of 192 healthy weaning piglets (Duroc × Landrace × Yorkshire, 21 d old) were blocked by BW (6.53 ± 0.60 kg) and randomly assigned to 4 dietary treatments: negative control (NC, basal diet), positive control (PC), basal diet + ZnO at 2 g/kg and antibiotics at 0.8 g/kg), SDPP (containing 5% SDPP), and SDCP (containing 5% SDCP). The experiment lasted 14 d. The SDPP group had higher (P < 0.05) final BW, average daily gain and average daily feed intake than the NC and SDCP groups. The percentage of piglets with fecal scores at 2 or ≥2 was higher (P < 0.05) in the NC and SDCP groups than in the PC group. A decreased (P < 0.05) bacterial alpha diversity and Bacteroidetes abundance, but increased (P < 0.05) Firmicutes abundance were observed in the PC and SDPP groups when compared to the NC group. The relative abundance of Lactobacillus was higher (P < 0.05) in the SDPP than in the SDCP group, and that of Streptococcus was higher (P < 0.01) in the PC and SDPP groups than in the NC group. The PC group also had higher (P < 0.01) Faecalibacterium abundance than the NC and SDCP groups. Additionally, the SDCP group had higher (P < 0.05) serum urea nitrogen than those fed other diets, and lower (P < 0.10) short-chain fatty acids to branched-chain fatty acids ratio than the PC and SDPP groups. Overall, SDPP was a promising animal protein for piglets in increasing feed intake, modifying gut microbiota profile, reducing gut protein fermentation and alleviating diarrhea frequency, thus promoting growth performance, under the conditions with limited in-feed utilization of antibiotics and ZnO.

Adsorption properties of albumin and fibrinogen on hydrophilic/hydrophobic TiO2 surfaces: A molecular dynamics study

In serval experimental researches, UV-induced hydrophilicity enabled better hemocompatibility in the TiO₂ surface, which was considered to be caused by the removal of the carboxylic acid contamination from the surface. In this paper, we altered the surface wetting property by applying the formate contamination on the rutile (110) surface, and systematically investigated the adsorption properties of albumin and fibrinogen on hydrophilic/hydrophobic TiO₂ surface. Unique contacts were found between the charged residues and the hydrophilic surface, anchoring the protein on the surface. The small size and the heart shape of albumin make it easy to cross the stable water layers near the surface. Besides, albumin has a higher proportion of charged residues, so it can form more unique contacts on the hydrophilic surface. Therefore, the albumin tends to adsorb on the hydrophilic surface. For the hydrophobic surface, the water layers near the surface are weakened, which helps the fibrinogen diffusing to the surface and adjusting its orientation. Although the hydrophobic surface cannot form the unique contacts, the larger size of fibrinogen can provide more residues to form enough ordinary contacts after adjusting, and then achieves stable adsorption. Therefore, fibrinogen tends to adsorb on the hydrophobic surface.

Interrogating preclinical study of liposomes: The effect of mouse strain reexamined

Mice are arguably the most important tool in the preclinical evaluation of liposomes; however, the effects of inter-strain physiological variabilities on in vivo performance of liposomes have been seriously overlooked. The present study validated that plasma proteins (PPs) and the capability of mononuclear phagocyte system (MPS) (typically expressed by phagocytosis rate, K) were mice strain-dependent. Physiological variabilities in PPs and the phagocytosis rate jointly contributed to the inter-strain inconsistency of pharmacokinetic (PK) profiles of liposomes. For the PPs sensitive liposomes (such as plain PEGylated liposomes and folic acid functionalized PEGylated liposomes), inter-strain variabilities in PK profiles could be calibrated using the corrected phagocytic rate (K_C = K×(c × Ig)/(alb×apo)), where c, Ig, alb and apo were respective the total content of complement proteins, immunoglobulins, albumin and apolipoproteins. While for the PPs insensitive liposomes (e.g., cRGD functionalized liposomes), phagocytic rate could be directly used to calibrate inter-strain difference of liposome PK profiles. Our data also warn that the reciprocal interaction between payloads and organisms would be much more complicated than that between liposomes and organisms, thus independent investigation should be conducted for each individual therapeutic agent.

A case study of poly (aryl ether sulfone) hemodialysis membrane interactions with human blood: Molecular dynamics simulation and experimental analyses

Patients with end-stage renal diseases (ESRD) require specific health cares as the accumulation of toxins due to the lack of kidney functionality would affect their lives. However, the mortality rate is still high due to cardiovascular diseases, socks, etc. A majority of patients with chronic kidney disease (CKD) require hemodialysis services. Blood purifying membranes, as the main component of hemodialysis setups, however, still suffer from lack of optimum biocompatibility, which results in morbidity and mortality of hemodialysis service receiving patients. The goal of the present case study is to have an in-depth understanding of the current blood-hemodialysis membrane interactions occurring during hemodialysis sessions using poly (aryl ether sulfone)-poly (vinyl pyrrolidone) (PAES-PVP) membrane. Attenuated total reflectance-Fourier transmission infrared (ATR-FTIR) spectroscopy, Raman spectroscopy, and solid-state nuclear magnetic resonance (SSNMR) spectroscopy were used to assess the initial chemical structure of the PAES-PVP membrane along with the variations after with the infections with human blood. Furthermore, scanning electron microscopy (SEM) and Transition electron microscopy (TEM) were used to visualize the structural variation of the membrane, blood aggregations, and blood clots on the membrane surface. Besides, Molecular dynamics (MD) simulation was used to assess the interaction of PAES-PVP with major human blood proteins, in terms of interaction energy, which is a novel contribution to the area. The macromolecules (human serum albumin (HSA), human serum transferrin (TRF), and human fibrinogen (HFG)) were chosen from the plasma protein component. These protein structures were chosen based on their different molecular size. Three advanced spectroscopy techniques and two advanced visualization techniques were used for the assessment of the membranes. Spectroscopy studies revealed amine related peak displacement and intensity shifts as indices for attachment of biological species to the polymeric membrane surfaces. Raman peaks around 370, 798, and 1299 cm^-1, which experienced significant shifts that were related to carbon-nitrogen and sulfur-oxygen bonds due to protein adhesion. Visualization techniques illustrated blood protein fouling patterns and extracellular vesicles' presence in the pore structures into membranes. The findings highlight the importance of whole structure biocompatibility improvement, rather than only focusing on surface modifications of hemodialysis membranes. Molecular dynamics simulation assessment showed various interaction behaviors for different proteins suggesting molecular weight and active residues of the protein macromolecules play an important role in interacting with polymeric structure. FB had the highest interaction (4,274,749.07 kcal/mol) and binding (10,370.90 kcal/mol) energy with the PAES-PVP structure. TRF owned the lowest interaction energy with respect to its lower molecular weight and fewer active residue count.

Synthesis of two novel pyrazolo[1,5-a]pyrimidine compounds with antibacterial activity and biophysical insights into their interactions with plasma protein

Two novel water-soluble pyrazolo[1,5-a]pyrimidine derivatives, 5-chloro-7-(4-methyl-piperazin -1-yl)-pyrazolo[1,5-a]pyrimidine (CMPS) and N'-(5-chloro-pyrazolo[1,5-a]pyrimidin-7-yl)-N,N-dimethyl -propane-1,3-diamine (NCPS), were synthesized and characterized with antibacterial activity. Then, the interactions of these compounds with bovine serum albumin (BSA) were studied by fluorescence, time-resolved fluorescence, circular dichroism (CD) spectroscopy and molecular docking. The results indicate that both CMPS and NCPS could effectively quench the intrinsic fluorescence of BSA via a static quenching process. The energy transfer from BSA to CMPS and NCPS may occur with high probability. Both CMPS and NCPS bind in the site I of BSA. The hydrophobic force and hydrogen bonds play major roles in the complex formation. Binding constants for both systems show that the affinity of CMPS binding to BSA is stronger than that of NCPS. The results of three-dimensional fluorescence and CD spectra reveal that the binding of CMPS and NCPS to BSA can induce conformational changes of BSA, and the influence of CMPS is slightly stronger than that of NCPS.

A large-scale genetic correlation scan identified the plasma proteins associated with brain function related traits

AIMS

Insomnia, intelligence and neuroticism are three typical traits and dysfunctions mainly regulated by human brain. Our research aimed to explore the potential genetic relationships between brain function related traits and more than 3000 human plasma proteins.

MATERIALS AND METHODS

We conducted a large-scale genetic correlation scan of human plasma proteins and three brain function related traits, including insomnia, intelligence and neuroticism. Linkage disequilibrium score regression (LDSC) analysis was performed to estimate the genetic correlations between each of the blood proteins and insomnia, intelligence and neuroticism via utilizing the genome-wide association study summary statistics of plasma proteins and those three traits.

RESULTS

LDSC analysis identified 18 specific plasma proteins shown suggestive genetic correlations with insomnia such as Periostin (coefficient=-0.3910, P value = 0.0070). Twenty-one plasma proteins exhibited genetic correlations with intelligence such as Ecto-ADP-ribosyltransferase 3 (coefficient = 0.3066, P value = 0.0013). Six specific plasma proteins shown suggestive genetic correlations with neuroticism, such as CD70 antigen (coefficient = 0.2979, P value = 0.0134). After further comparing the suggestive proteins between insomnia, intelligence and neuroticism, we detected 3 common plasma proteins shared by insomnia and intelligence such as Periostin (coefficient _insomnia =-0.3910, P_insomnia value = 0.0070; coefficient _intelligence =0.2673, P_intelligence value = 0.0159) and Neurexin-1 (coefficient _insomnia =-0.2913, P_insomnia value = 0.0197; coefficient _intelligence = 0.2399, P_intelligence value = 0.0035). We also detected 2 common plasma proteins shared by intelligence and neuroticism, including CD70 antigen (coefficient _intelligence =-0.2092, P_intelligence value = 0.0337; coefficient _neuroticism = 0.2979, P_neuroticism value = 0.0134).

CONCLUSION

Our results provide novel clues for unveiling the functional relevance of plasma proteins and brain function related traits.

A novel WSSV responsive plasma protein from Litopenaeus vannamei contributes to hemocytes anti-apoptosis

Litopenaeus vannamei, as an important marine aquaculture species, has attracted more and more attentions in past several years. More recently people got its genome fine mapping, which unveiled a gene treasure. In this study, we have identified a novel trypsin-like protein which came from previous WSSV-infected shrimp plasma iTRAQ data. This protein is a 39 kDa protein with 363 amino acids. It contains a conserved trypsin-domain and could be strongly induced with WSSV infection. Interestingly, knockdown of this protein made shrimps vulnerable to WSSV infection. Further exploration unveiled that this fragility was probably due to the fact that knockdown of this protein could cause shrimp hemocytes apoptosis, which indicated that this protein played key roles in preventing shrimp hemocytes from apoptosis. To further explore how LvTLAP protected shrimp hemocytes from apoptosis, GST pull down assay was applied to screen LvTLAP interacting protein in shrimp plasma. L. vannamei growth and transformation-dependent-like protein (LvGTD-like protein) was identified as a LvTLAP interacting protein, which played proapoptotic roles in cells. Thus, a possible explanation for LvTLAP anti-apoptosis activity was that this protein could block LvGTD-like protein proapoptotic activity to protect shrimp hemocytes from death. In general, our study has uncovered a novel WSSV responsive shrimp plasma protein, which played key roles in shrimp hemocytes anti-apoptosis and shrimp against WSSV infection.

A plasma proteogenomic signature for fibromuscular dysplasia

AIMS

Fibromuscular dysplasia (FMD) is a poorly understood disease that predominantly affects women during middle-life, with features that include stenosis, aneurysm, and dissection of medium-large arteries. Recently, plasma proteomics has emerged as an important means to understand cardiovascular diseases. Our objectives were: (i) to characterize plasma proteins and determine if any exhibit differential abundance in FMD subjects vs. matched healthy controls and (ii) to leverage these protein data to conduct systems analyses to provide biologic insights on FMD, and explore if this could be developed into a blood-based FMD test.

METHODS AND RESULTS

Females with 'multifocal' FMD and matched healthy controls underwent clinical phenotyping, dermal biopsy, and blood draw. Using dual-capture proximity extension assay and nuclear magnetic resonance-spectroscopy, we evaluated plasma levels of 981 proteins and 31 lipid sub-classes, respectively. In a discovery cohort (Ncases = 90, Ncontrols = 100), we identified 105 proteins and 16 lipid sub-classes (predominantly triglycerides and fatty acids) with differential plasma abundance in FMD cases vs. controls. In an independent cohort (Ncases = 23, Ncontrols = 28), we successfully validated 37 plasma proteins and 10 lipid sub-classes with differential abundance. Among these, 5/37 proteins exhibited genetic control and Bayesian analyses identified 3 of these as potential upstream drivers of FMD. In a 3rd cohort (Ncases = 506, Ncontrols = 876) the genetic locus of one of these upstream disease drivers, CD2-associated protein (CD2AP), was independently validated as being associated with risk of having FMD (odds ratios  = 1.36; P = 0.0003). Immune-fluorescence staining identified that CD2AP is expressed by the endothelium of medium-large arteries. Finally, machine learning trained on the discovery cohort was used to develop a test for FMD. When independently applied to the validation cohort, the test showed a c-statistic of 0.73 and sensitivity of 78.3%.

CONCLUSION

FMD exhibits a plasma proteogenomic and lipid signature that includes potential causative disease drivers, and which holds promise for developing a blood-based test for this disease.

Astakine1 forms protein complex in plasma

Astakine 1 is a small cytokine-like peptide which is directly involved in hematopoiesis in crustaceans. Astakines are present in many different invertebrate groups primarily in arthropods. In this study we found that astakine1 was present as a high molecular weight (HMW) complex in plasma. It is known that calcium concentration are fluctuating in several crustaceans especially during the molting process. This HMW-complex was formed under low calcium concentrations in plasma and could be partially reversed provided calcium was added. The biological function of the naïve astakine1 and that in the HMW complex was about the same, but if the protein is to be isolated or studied for its function it is important to know about this property of astakine1 which may previously have hampered isolation and functional studies in other animals than freshwater crayfish.

Plasma vascular non-inflammatory molecule 3 is associated with gastrointestinal acute graft-versus-host disease in mice

Background

Gastrointestinal acute graft-versus-host disease (GI aGVHD) is a lethal complication following allogeneic hematopoietic stem cell transplantation (HSCT). However, it is still very difficult to make a diagnosis of GI aGVHD in practice. To date, no consensus plasma biomarker of GI aGVHD can be used to help make a diagnosis. Here, we attempted to identify GI aGVHD associated plasma proteins in murine model, which can help make a diagnosis of GI aGVHD.

Methods

We used 8-plex isobaric tags for relative and absolute quantitation (8-plex iTRAQ) to screen out proteins in plasma samples taken from murine models before and after allogeneic HSCT. Next mRNA expressions were validated by quantitative real-time polymerase chain reaction in mouse intestinal epithelial samples.

Results

We found that five proteins were increased at least 2-fold in the allogeneic group at day 7 compared with days 0, 3 and 15 (after Cyclosporin A treatment) and the syngeneic group at day 7. These 5 proteins were VNN3, ZNF746, C4BP, KNG1 and FETUB, and they were consistent with results from negative labeling with 8-plex iTRAQ. Furthermore, increase in mRNA level of VNN3 was confirmed in murine intestinal epithelial samples with aGVHD.

Conclusions

Our results demonstrate that plasma VNN3 protein is associated with GI aGVHD in murine model.

Electronic supplementary material

The online version of this article (10.1186/s12950-017-0178-z) contains supplementary material, which is available to authorized users.

Changes in pre- and post-donation platelet function in plateletpheresis donors

OBJECTIVES

This study aimed to investigate the changes of platelet (PLT) function and coagulation time before and after plateletpheresis donation.

MATERIAL AND METHODS

The healthy donors were divided into four groups according to the annual number of plateletpheresis donation: 20 times group, 15 times group, 10 times group and 5 times group. The healthy non-blood donors were selected as controls. The donation interval was 14 days. The blood samples were collected before plateletpheresis donation and after 30min, 7 d, and 14 d of donation for determination of coagulation time, PLT function, plasma protein, serum iron and blood routine change.

RESULTS

After 30min of plateletpheresis donation, the PLT function decreased and the coagulation time was prolonged. However, PLT function recovered to the pre-collection after 7 d of plateletpheresis donation and coagulation time recovered to the pre-collection after 14 d of plateletpheresis donation. Additionally, there was no difference regarding blood coagulation time and PLT function among blood donors and controls. The plasma protein and serum iron levels in 20 times and 15 times groups were within the normal reference range.

CONCLUSION

The frequency of plateletpheresis donation will not affect PLT function, coagulation time, plasma protein and serum iron in donors.

High-fat diet-induced plasma protein and liver changes in obese rats can be attenuated by melatonin supplementation

Obesity triggers changes in protein expression in various organs that might participate in the pathogenesis of obesity. Melatonin has been reported to prevent or attenuate such pathological protein changes in several chronic diseases. However, such melatonin effects on plasma proteins have not yet been studied in an obesity model. Using a proteomic approach, we investigated the effect of melatonin on plasma protein profiles after rats were fed a high-fat diet (HFD) to induce obesity. We hypothesized that melatonin would attenuate abnormal protein expression in obese rats. After 10weeks of the HFD, animals displayed increased body weight and fat accumulation as well as increased glucose levels, indicating an obesity-induced prediabetes mellitus-like state. Two-dimensional gel electrophoresis and liquid chromatography-mass spectrometry/mass spectrometry revealed 12 proteins whose expression was altered in response to the HFD and the melatonin treatment. The altered proteins are related to the development of liver pathology, such as cirrhosis (α1-antiproteinase), thrombosis (fibrinogen, plasminogen), and inflammation (mannose-binding protein A, complement C4, complement factor B), contributing to liver steatosis or hepatic cell death. Melatonin treatment most probably reduced the severity of the HFD-induced obesity by reducing the amplitude of HFD-induced plasma protein changes. In conclusion, we identified several potential biomarkers associated with the progression of obesity and its complications, such as liver damage. Furthermore, our findings reveal melatonin's beneficial effect of attenuating plasma protein changes and liver pathogenesis in obese rats.

Directing membrane chromatography to manufacture α1-antitrypsin from human plasma fraction IV

The surging demand for plasma proteins, mainly driven by the growing market and the development of new therapeutic indications, is promoting manufacturers to improve the throughput of plasma proteins. Due to the inherent convective mass transfer, membrane chromatography has been proved to be an efficient approach for extracting a small amount of target proteins from large-volume feed. In this study, α1-antitrypsin (AAT) was extracted from human plasma fraction IV by a two-step membrane chromatography. An anion-exchange membrane chromatography (AEMC) was used to capture the plasma proteins in bind/elute mode, and the obtained effluent was further polished by a hydrophobic interaction membrane chromatography (HIMC) in flow-through mode. Under optimal conditions, the recovery and purity of AAT achieved 87.0% and 0.58 AAT/protein (g/g) by AEMC, respectively. After the precise polishing by HIMC, the purity of AAT was 1.22 AAT/protein (g/g). The comparison results showed that membrane chromatography outperformed column chromatography in both steps because of its high throughput. This two-step membrane chromatography could obtain an AAT recovery of 83.3% and an activity recovery of 91.4%. The outcome of this work not only offers an alternative process for protein purification from plasma, but also provides guidelines for manufacturing product from a large-volume feed with multi-components by membrane chromatography.

Maternal plasma protein profiles in response to oral 50-gram glucose load in mid-pregnancy: a pilot study

Accumulating evidence documents the initiation of diverse physiologic and biochemical response subsequent to an oral glucose load. However, significant gaps in knowledge exist in the understanding of consequences of glucose load during pregnancy, a state of insulin resistance. Using high dimensional protein arrays, we conducted a pilot proof-of-concept and feasibility study to investigate profiles of 120 plasma proteins in pre- and post- 50-gram oral glucose challenge samples. Participants (N = 10) were selected from among women enrolled in a pregnancy cohort. Differences in plasma protein concentrations between pre- and post-glucose load challenge samples were evaluated using Student's T-test (paired) and mean fold change comparisons. Multiple testing adjusted p-values (i.e., false discovery rate q values) were computed using Benjamini-Hochberg (BH) corrections. Plasma haptoglobulin, epidermal growth factor, hemoglobin, thrombospondin-1, and S100 protein concentrations were two to five fold higher in post-glucose load compared with pre-glucose load samples (all q-values <0.05). Among women aged >31 years (above median), post-load S100 protein was elevated 9.92-fold above pre-load concentrations, while it was elevated 4.10-fold among women aged <31 years (below median). Similarly, among women with post-load glucose concentrations <101mg/dl (below median), S100 was elevated 8.26-fold while it was elevated 3.28 fold among women with post-load glucose concentrations >101mg/dl (above median). Our study findings suggest that post-glucose load changes in plasma biomarkers represent a diverse set of cellular responses including receptor for advanced glycation end products (RAGE), inflammation, oxidative stress and adipogenesis, during mid-pregnancy. Future studies of larger populations and longer periods of follow-up are warranted.