Plasma Polyamines and Short-Term Adverse Outcomes Among Patients With Ischemic Stroke: A Prospective Cohort Study.

BACKGROUND: Polyamines have been reported to be associated with neurological function, but the associations between polyamines and the prognosis of ischemic stroke remain unclear. We aimed to prospectively investigate whether elevated plasma polyamine levels are associated with adverse outcomes in patients with ischemic stroke. METHODS AND RESULTS: Plasma polyamine levels were measured at admission in 3570 patients with acute ischemic stroke, and clinical outcomes were assessed at 3 months after stroke onset. The primary outcome was a composite outcome of death and major disability (modified Rankin Scale score≥3), and secondary outcomes included the individual outcomes of death and major disability. During a 3-month follow-up period, 877 participants (25.1%) experienced the primary outcome. Increased putrescines were associated with a decreased risk of the primary outcome (the highest versus the lowest tertile: odds ratio, 0.72 [95% CI, 0.58-0.91]; P=0.005) and major disability (odds ratio, 0.59 [95% CI, 0.47-0.74]; P<0.001). Conversely, increased spermidines were associated with an increased risk of death (hazard ratio, 1.86 [95% CI, 1.10-3.14]; P=0.020), and increased spermines were associated with an increased risk of the primary outcome (odds ratio, 1.36 [95% CI, 1.08-1.71]; P=0.009) and major disability (odds ratio, 1.27 [95% CI, 1.01-1.59]; P=0.041). CONCLUSIONS: Among patients with ischemic stroke, high plasma putrescine levels were associated with a decreased risk of adverse outcomes, whereas high plasma spermidine and spermine levels were associated with an increased risk of adverse outcomes. Further studies are needed to investigate whether targeting these polyamines can improve the prognosis of patients with ischemic stroke. REGISTRATION: https://clinicaltrials.gov. Identifier: NCT01840072.

Relationships of Gut Microbiota Composition, Short-Chain Fatty Acids and Polyamines with the Pathological Response to Neoadjuvant Radiochemotherapy in Colorectal Cancer Patients.

Emerging evidence has suggested that dysbiosis of the gut microbiota may influence the drug efficacy of colorectal cancer (CRC) patients during cancer treatment by modulating drug metabolism and the host immune response. Moreover, gut microbiota can produce metabolites that may influence tumor proliferation and therapy responsiveness. In this study we have investigated the potential contribution of the gut microbiota and microbial-derived metabolites such as short chain fatty acids and polyamines to neoadjuvant radiochemotherapy (RCT) outcome in CRC patients. First, we established a profile for healthy gut microbiota by comparing the microbial diversity and composition between CRC patients and healthy controls. Second, our metagenomic analysis revealed that the gut microbiota composition of CRC patients was relatively stable over treatment time with neoadjuvant RCT. Nevertheless, treated patients who achieved clinical benefits from RTC (responders, R) had significantly higher microbial diversity and richness compared to non-responder patients (NR). Importantly, the fecal microbiota of the R was enriched in butyrate-producing bacteria and had significantly higher levels of acetic, butyric, isobutyric, and hexanoic acids than NR. In addition, NR patients exhibited higher serum levels of spermine and acetyl polyamines (oncometabolites related to CRC) as well as zonulin (gut permeability marker), and their gut microbiota was abundant in pro-inflammatory species. Finally, we identified a baseline consortium of five bacterial species that could potentially predict CRC treatment outcome. Overall, our results suggest that the gut microbiota may have an important role in the response to cancer therapies in CRC patients.

Circulating acetylated polyamines correlate with Covid-19 severity in cancer patients.

Cancer patients are particularly susceptible to the development of severe Covid-19, prompting us to investigate the serum metabolome of 204 cancer patients enrolled in the ONCOVID trial. We previously described that the immunosuppressive tryptophan/kynurenine metabolite anthranilic acid correlates with poor prognosis in non-cancer patients. In cancer patients, we observed an elevation of anthranilic acid at baseline (without Covid-19 diagnosis) and no further increase with mild or severe Covid-19. We found that, in cancer patients, Covid-19 severity was associated with the depletion of two bacterial metabolites, indole-3-proprionate and 3-phenylproprionate, that both positively correlated with the levels of several inflammatory cytokines. Most importantly, we observed that the levels of acetylated polyamines (in particular N1-acetylspermidine, N1,N8-diacetylspermidine and N1,N12-diacetylspermine), alone or in aggregate, were elevated in severe Covid-19 cancer patients requiring hospitalization as compared to uninfected cancer patients or cancer patients with mild Covid-19. N1-acetylspermidine and N1,N8-diacetylspermidine were also increased in patients exhibiting prolonged viral shedding (>40 days). An abundant literature indicates that such acetylated polyamines increase in the serum from patients with cancer, cardiovascular disease or neurodegeneration, associated with poor prognosis. Our present work supports the contention that acetylated polyamines are associated with severe Covid-19, both in the general population and in patients with malignant disease. Severe Covid-19 is characterized by a specific metabolomic signature suggestive of the overactivation of spermine/spermidine N1-acetyl transferase-1 (SAT1), which catalyzes the first step of polyamine catabolism.

A Blood-based Polyamine Signature Associated With MEN1 Duodenopancreatic Neuroendocrine Tumor Progression.

CONTEXT: Duodenopancreatic neuroendocrine tumors (dpNETs) frequently occur in patients with multiple endocrine neoplasia type 1 (MEN1), and metastatic dpNET is the primary cause of disease-related mortality. There is a need for biomarkers that can identify patients with MEN1-related dpNETs that are at high risk of developing distant metastasis. Polyamines have tumor-promoting roles in several cancer types. OBJECTIVE: We hypothesized that MEN1-dpNET-related disease progression is associated with elevated levels of circulating polyamines. METHODS: Through an international collaboration between The University of Texas MD Anderson Cancer Center, the National Institutes of Health, and the University Medical Center Utrecht, plasma polyamine levels were assessed using mass spectrometry in 84 patients with MEN1 (20 with distant metastatic dpNETs [patients] and 64 with either indolent dpNETs or no dpNETs [controls]). A mouse model of MEN1-pNET, Men1fl/flPdx1-CreTg, was used to test time-dependent changes in plasma polyamines associated with disease progression. RESULTS: A 3-marker plasma polyamine signature (3MP: N-acetylputrescine, acetylspermidine, and diacetylspermidine) distinguished patients with metastatic dpNETs from controls in an initial set of plasmas from the 3 participating centers. The fixed 3MP yielded an area under the curve of 0.84 (95% CI, 0.62-1.00) with 66.7% sensitivity at 95% specificity for distinguishing patients from controls in an independent test set from MDACC. In Men1fl/flPdx1-CreTg mice, the 3MP was elevated early and remained high during disease progression. CONCLUSION: Our findings provide a basis for prospective testing of blood-based polyamines as a potential means for monitoring patients with MEN1 for harboring or developing aggressive disease.

Simultaneous Determination of Polyamines and Steroids in Human Serum from Breast Cancer Patients Using Liquid Chromatography-Tandem Mass Spectrometry.

A simultaneous quantitative profiling method for polyamines and steroids using liquid chromatography-tandem mass spectrometry was developed and validated. We applied this method to human serum samples to simultaneously evaluate polyamine and steroid levels. Chemical derivatization was performed using isobutyl chloroformate to increase the sensitivity of polyamines. The method was validated, and the matrix effects were in the range of 78.7-126.3% and recoveries were in the range of 87.8-123.6%. Moreover, the intra-day accuracy and precision were in the ranges of 86.5-116.2% and 0.6-21.8%, respectively, whereas the inter-day accuracy and precision were in the ranges of 82.0-119.3% and 0.3-20.2%, respectively. The linearity was greater than 0.99. The validated method was used to investigate the differences in polyamine and steroid levels between treated breast cancer patients and normal controls. In our results, N-acetyl putrescine, N-acetyl spermidine, cadaverine, 1,3-diaminopropane, and epitestosterone were significantly higher in the breast cancer patient group. Through receiver operating characteristic curve analysis, all metabolites that were significantly increased in patient groups with areas under the curve >0.8 were shown. This mass spectrometry-based quantitative profiling method, used for the investigation of breast cancer, is also applicable to androgen-dependent diseases and polyamine-related diseases.

Spermidine is not an independent factor regulating limb muscle mass in mice following androgen deprivation.

Maintaining a critical amount of skeletal muscle mass is linked to reduced morbidity and mortality. In males, testicular androgens regulate muscle mass with a loss of androgens being critical as it is associated with muscle atrophy. Atrophy of the limb muscles is particularly important, but the pathways by which androgens regulate limb muscle mass remain equivocal. We used microarray analysis to identify changes to genes involved with polyamine metabolism in the tibialis anterior (TA) muscle of castrated mice. Of the polyamines, the concentration of spermidine (SPD) was significantly reduced in the TA of castrated mice. To assess whether SPD was an independent factor by which androgens regulate limb muscle mass, we treated castrated mice with SPD for 8 weeks and compared them with sham operated mice. Though this treatment paradigm effectively restored SPD concentrations in the TA muscles of castrated mice, mass of the limb muscles (i.e., TA, gastrocnemius, plantaris, and soleus) were not increased to the levels observed in sham animals. Consistent with those findings, muscle force production was also not increased by SPD treatment. Overall, these data demonstrate for the first time that SPD is not an independent factor by which androgens regulate limb skeletal muscle mass. Novelty: Polyamines regulate growth in various cells/tissues. Spermidine concentrations are reduced in the limb skeletal muscle following androgen depletion. Restoring spermidine concentrations in the limb skeletal muscle does not increase limb muscle mass or force production.

A preliminary study procedure for detection of polyamines in plasma samples as a potential diagnostic tool in prostate cancer.

BACKGROUND: Many scientific contributions recognize polyamines as important biomarkers for the diagnosis and treatment of cancer. Several authors have suggested the use of LC/MS instruments as an elective method for their measurement, providing good detection limits and specificity; however, many of these procedures suffer from long chromatographic run times, high detection limits and lengthy and expensive sample pre-treatment steps. METHODS: UHPLC coupled with high-resolution Orbitrap mass spectrometry (UHPLC/Orbitrap) was set up for the identification and separation ofpolyamines, together with some of their metabolites and catabolites, in the plasma of healthy and prostate cancer human patients. Thirteen metabolites were measured in deproteinized plasma samples through a new analytical approach known as the parallel reaction monitoring (PRM) for targeted quantitative analysis. RESULTS: The calibration curves were linear and R2 ranged from 0.9913 to 0.9995 for all analytes. LOQ values are between 0.382 and 25 ng mL-1 and LOD values are between 0.109 and 7.421 ng mL-1. The method shows an accuracy and precision for intra-day and inter-day < 15% RSD and R.E.% for all the QC samples. The matrix effect calculated at different concentration levels did not exceed 15%. CONCLUSIONS: The method developed provides rapid, easy and robust identification and measurement of a wide range of polyamines, and some of their metabolites that can be evaluated as biomarkers to predict the clinical features of prostate cancer patients, avoiding invasive diagnostic procedures.

Differential expression of polyamine biosynthetic pathways in skin lesions and in plasma reveals distinct profiles in diffuse cutaneous leishmaniasis.

Tegumentary leishmaniasis (TL) is a parasitic disease that can result in wide spectrum clinical manifestations. It is necessary to understand host and parasite determinants of clinical outcomes to identify novel therapeutic targets. Previous studies have indicated that the polyamine biosynthetic pathway is critical for Leishmania growth and survival. Despite its importance, expression of the such pathway has not been previously investigated in TL patients. We performed an exploratory analysis employing Systems Biology tools to compare circulating polyamines and amino acid concentration as well as polyamine pathway gene expression in cutaneous lesions patients presenting with distinct TL disease presentations. Diffuse cutaneous leishmaniasis (DCL) was associated with higher concentrations of amino acids, polyamines and its substrate transporters than mucosal cutaneous leishmaniasis or localized cutaneous leishmaniasis. In addition, the RNA expression of polyamine-related genes of patients lesions from two separate cohorts demonstrated that differential activation of this pathway is associated with parasite loads and able to discriminate the clinical spectrum of TL. Taken together, our findings highlight a new aspect of DCL immunopathogenesis indicating that the polyamine pathway may be explored as a novel therapeutic target to control disease burden.

Anti-GD2 induced allodynia in rats can be reduced by pretreatment with DFMO.

BACKGROUND: Anti-GD2 therapy with dinutuximab is effective in improving the survival of high-risk neuroblastoma patients in remission and after relapse. However, allodynia is the major dose-limiting side effect, hindering its use for neuroblastoma patients at higher doses and for other GD2-expressing malignancies. As polyamines can enhance neuronal sensitization, including development of allodynia and other forms of pathological pain, we hypothesized that polyamine depletion might prove an effective strategy for relief of anti-GD2 induced allodynia. METHOD: Sprague-Dawley rats were allowed to drink water containing various concentrations of difluoromethylornithine (DFMO) for several days prior to behavioral testing. Anti-GD2 (14G2a) was injected into the tail vein of lightly sedated animals and basal mechanical hindpaw withdrawal threshold assessed by von Frey filaments. Endpoint serum DFMO and polyamines, assessed 24h after 14G2a injection, were measured by HPLC and mass spectrometry. RESULTS: An i.v. injection of 14G2a causes increased paw sensitivity to light touch in this model, a response that closely mimics patient allodynia. Animals allowed to drink water containing 1% DFMO exhibited a significant reduction of 14G2a-induced pain sensitivity (allodynia). Increasing the dosage of the immunotherapeutic increased the magnitude (intensity and duration) of the pain behavior. Administration of DFMO attenuated the enhanced sensitivity. Consistent with the known actions of DFMO on ornithine decarboxylase (ODC), serum putrescene and spermidine levels were significantly reduced by DFMO, though the decrease in endpoint polyamine levels did not directly correlate with the behavioral changes. CONCLUSIONS: Our results demonstrate that DFMO is an effective agent for reducing anti-GD2 -induced allodynia. Using DFMO in conjunction with dinutuximab may allow for dose escalation in neuroblastoma patients. The reduction in pain may be sufficient to allow new patient populations to utilize this therapy given the more acceptable side effect profile. Thus, DFMO may be an important adjunct to anti-GD2 immunotherapy in addition to a role as a potential anti-cancer therapeutic.

Effect of a lifestyle intervention program with energy-restricted Mediterranean diet and exercise on the serum polyamine metabolome in individuals at high cardiovascular disease risk: a randomized clinical trial.

BACKGROUND: Many food items included in the Mediterranean diet (MedDiet) are rich in polyamines, small aliphatic amines with potential cardioprotective effects. The consumption of a MedDiet could increase polyamine concentrations. Based on experimental models, polyamine concentrations may be also influenced by physical activity (PA). OBJECTIVES: We aimed to evaluate whether an intervention based on an energy-restricted MedDiet (er-MedDiet) and PA promotion, in comparison with an energy-unrestricted MedDiet and traditional health care, influences the serum pattern of polyamines and related metabolites in subjects at high risk of cardiovascular disease (CVD). METHODS: This was a substudy from the PREDIMED-Plus trial, an ongoing randomized clinical trial including 6874 participants allocated either to an intensive weight-loss lifestyle intervention based on er-MedDiet, PA promotion, and behavioral support (er-MedDiet + PA group), or to an energy-unrestricted MedDiet and traditional health care group (MedDiet group). A total of 75 patients (n = 38, er-MedDiet + PA group; n = 37, MedDiet group) were included in this study. Serum concentrations of arginine, ornithine, polyamines, and acetyl polyamines at baseline and 26 wk of intervention were measured by an ultra-high-performance LC-tandem MS platform. RESULTS: At week 26, study groups had similar adherence to the MedDiet but patients randomly assigned to the er-MedDiet + PA group showed significantly lower mean energy intake (-340.3 kcal/d; 95% CI: -567.3, -113.4 kcal/d; P = 0.004), higher mean PA (1290.6; 95% CI: 39.9, 2541.3 metabolic equivalent tasks · min/d; P = 0.043), and higher mean decrease in BMI (in kg/m2) (-1.3; 95% CI: -1.8, -0.6; P < 0.001) than the MedDiet group. However, no significant differences in serum polyamines or related metabolites were found between study groups after 26 wk of intervention and no significant between-group differences were found in glycated hemoglobin, HDL-cholesterol, or triglyceride concentrations. CONCLUSIONS: In individuals at high CVD risk, an er-MedDiet with increased PA did not result in significant changes of serum concentrations of polyamines or related metabolites in comparison with an energy-unrestricted MedDiet and no increase in PA. This trial was registered at isrctn.com as ISRCTN89898870.

LC-MS analyses revealed significant metabolic changes associated with the docosahexaenoic acid supplementation in rats.

Evidences suggest that dietary docosahexaenoic acid (DHA) supplementation may have pleiotropic beneficial effects on health. However, the underlying mechanisms and crucial targets that are involved in achieving these benefits remain to be clarified. In this study, we employed biochemical analysis and liquid chromatography-mass spectrometry (LC-MS) based untargeted metabolomics coupled with multivariate statistical analysis to identify potential metabolic targets of DHA in adult rats at 48 h post-feeding. Blood biochemical analysis showed a significant decrease in triglyceride level of DHA diet group, the untargeted metabolomic analysis revealed that some metabolites were significantly different between the DHA diet group and the basal diet group, including fatty acids (16:0, 18:1, 20:5n3, 22:2n6 and 24:0), diglyceride (20:0/18:2n6, 18:3n6/22:6n3, 20:4n3/20:4n3, and 22:0/24:0), PIP2 (18:2/20:3), phytol, lysoSM (d18:1), 12-hydroxyheptadecatrienoic acid, dihydrocorticosterone and N1-acetylspermine, which are mainly involved in fat mobilization and triglyceride hydrolysis, arachidonic acid, steroid hormone, and polyamine metabolism. To our knowledge, this is the first report that links the metabolic effects of DHA with arachidonic acid, steroid, and polyamine metabolism. Our finding suggests that the beneficial effects of DHA, may not directly require its own metabolic derivatives, but could be achieved by metabolic regulation.

Gender-Related Differences on Polyamine Metabolome in Liquid Biopsies by a Simple and Sensitive Two-Step Liquid-Liquid Extraction and LC-MS/MS.

Polyamines are involved in the regulation of many cellular functions and are promising biomarkers of numerous physiological conditions. Since the concentrations of these compounds in biological fluids are low, sample extraction is one of the most critical steps of their analysis. Here, we developed a comprehensive, sensitive, robust, and high-throughput LC-MS/MS stable-isotope dilution method for the simultaneous determination of 19 metabolites related to polyamine metabolism, including polyamines, acetylated and diacetylated polyamines, precursors, and catabolites from liquid biopsies. The sample extraction was optimized to remove interfering compounds and to reduce matrix effects, thus being useful for large clinical studies. The method consists of two-step liquid-liquid extraction with a Folch extraction and ethyl acetate partitioning combined with dansyl chloride derivatization. The developed method was applied to a small gender-related trial concerning human serum and urine samples from 40 obese subjects. Sex differences were found for cadaverine, putrescine, 1,3-diaminopropane, γ-aminobutyric acid, N8-acetylspermidine, and N-acetylcadaverine in urine; N1-acetylspermine in serum; and spermine in both serum and urine. The results demonstrate that the developed method can be used to analyze biological samples for the study of polyamine metabolism and its association with human diseases.

Decreased plasmatic spermidine and increased spermine in mild cognitive impairment and Alzheimer's disease patients

Abstract Background Current evidence suggests that upregulation of polyamines system plays a role both in cognitive deficit and synaptic loss observed in Alzheimer's disease (AD). Objective The aim of this study was to determine the plasmatic concentration of polyamines in mild cognitive impairment (MCI) and AD patients in comparison with healthy controls (HC). Methods Plasmatic polyamines were quantified using the AbsoluteIDQ® p180 and liquid chromatography coupled to tandem mass spectrometry (LC/MS-MS). Results The study group comprised 34 AD patients, 20 MCI and 25 HC. All individuals were followed for 4 years. During this period 8 amnestic MCI patients (40% of the MCI sample at baseline) converted to AD. Spermidine level was lower in both patient groups (AD; MCI) compared to HC (p = 0.007). Plasma levels of spermine were higher in the MCI group (p < 0.001), but decreased in the sub-sample of MCI patients who converted to AD (p = 0.043). No statistically significant differences were found in ornithine and putrescine levels (p = 0.056 and p = 0.126, respectively). Discussion Our results suggest dynamic changes in the expression of polyamines in the MCI-AD continuum.

Ozone-induced changes in the serum metabolome: Role of the microbiome.

Ozone is an asthma trigger. In mice, the gut microbiome contributes to ozone-induced airway hyperresponsiveness, a defining feature of asthma, but the mechanistic basis for the role of the gut microbiome has not been established. Gut bacteria can affect the function of distal organs by generating metabolites that enter the blood and circulate systemically. We hypothesized that global metabolomic profiling of serum collected from ozone exposed mice could be used to identify metabolites contributing to the role of the microbiome in ozone-induced airway hyperresponsiveness. Mice were treated for two weeks with a cocktail of antibiotics (ampicillin, neomycin, metronidazole, and vancomycin) in the drinking water or with control water and then exposed to air or ozone (2 ppm for 3 hours). Twenty four hours later, blood was harvested and serum analyzed via liquid-chromatography or gas-chromatography coupled to mass spectrometry. Antibiotic treatment significantly affected 228 of the 562 biochemicals identified, including reductions in the known bacterially-derived metabolites, equol, indole propionate, 3-indoxyl sulfate, and 3-(4-hydroxyphenyl)propionate, confirming the efficacy of the antibiotic treatment. Ozone exposure caused significant changes in 334 metabolites. Importantly, ozone-induced changes in many of these metabolites were different in control and antibiotic-treated mice. For example, most medium and long chain fatty acids declined by 20-50% with ozone exposure in antibiotic-treated but not control mice. Most taurine-conjugated bile acids increased with ozone exposure in antibiotic-treated but not control mice. Ozone also caused marked (9-fold and 5-fold) increases in the polyamines, spermine and spermidine, respectively, in control but not antibiotic-treated mice. Each of these metabolites has the capacity to alter airway responsiveness and may account for the role of the microbiome in pulmonary responses to ozone.

A metabolic profile of polyamines in parkinson disease: A promising biomarker.

OBJECTIVE: Aging is the highest risk factor for Parkinson disease (PD). Under physiological conditions, spermidine and spermine experimentally enhance longevity via autophagy induction. Accordingly, we evaluated the ability of each polyamine metabolite to act as an age-related, diagnostic, and severity-associated PD biomarker. METHODS: Comprehensive metabolome analysis of plasma was performed in Cohort A (controls, n = 45; PD, n = 145), followed by analysis of 7 polyamine metabolites in Cohort B (controls, n = 49; PD, n = 186; progressive supranuclear palsy, n = 19; Alzheimer disease, n = 23). Furthermore, 20 patients with PD who were successively examined within Cohort B were studied using diffusion tensor imaging (DTI). Association of each polyamine metabolite with disease severity was assessed according to Hoehn and Yahr stage (H&Y) and Unified Parkinson's Disease Rating Scale motor section (UPDRS-III). Additionally, the autophagy induction ability of each polyamine metabolite was examined in vitro in various cell lines. RESULTS: In Cohort A, N8-acetylspermidine and N-acetylputrescine levels were significantly and mildly elevated in PD, respectively. In Cohort B, spermine levels and spermine/spermidine ratio were significantly reduced in PD, concomitant with hyperacetylation. Furthermore, N1,N8-diacetylspermidine levels had the highest diagnostic value, and correlated with H&Y, UPDRS-III, and axonal degeneration quantified by DTI. The spermine/spermidine ratio in controls declined with age, but was consistently suppressed in PD. Among polyamine metabolites, spermine was the strongest autophagy inducer, especially in SH-SY5Y cells. No significant genetic variations in 5 genes encoding enzymes associated with spermine/spermidine metabolism were detected compared with controls. INTERPRETATION: Spermine synthesis and N1,N8-diacetylspermidine may respectively be useful diagnostic and severity-associated biomarkers for PD. ANN NEUROL 2019;86:251-263.

A Safe and Efficient Strategy for the Rapid Elimination of Blood Lead In†Vivo Based on a Capture-Fix-Separate Mechanism.

Lead poisoning is an important problem because of its serious effects on human health. Yet a solution is not available due to an incomplete understanding of the state of lead ions in blood. Since most blood lead binds to hemoglobin (Hb) in red blood cells, identifying and capturing lead-contaminated Hb in RBCs is important. Herein, a magnetic blood lead remover with hyperbranched poly(amidoamine)s (HPAM) as template/co-adsorbent and core-shell mesoporous structure was synthesized. Lead-containing Hb was selectively captured and then fixed by mesoporous channels. The magnetic separation technology was used to separate the magnetic remover from blood. A related blood lead clean-up apparatus was used to remove lead from the blood of a pig in vivo. Results of physical/chemical characterizations, biocompatibility experiments, animal tests, and theoretical simulation verify the safety and efficiency of this removal strategy and the high efficiency of the blood lead clean-up apparatus.

An extendable all-in-one injection twin derivatization LC-MS/MS strategy for the absolute quantification of multiple chemical-group-based submetabolomes.

The ability of LC-MS/MS for high coverage metabolite analysis lags behind the requirements of global metabolomics. The introduction of chemical derivatizations could significantly extend the ability of LC-MS/MS with enhanced MS response and improved LC separation, which has been serving as a promising quantitative tool for metabolomic analysis. However, as one specific derivatization reagent usually targets to a certain moiety, only a single chemical-group-based submetabolome could be analyzed in one injection. Therefore, the coverage of detected metabolites by derivatization-based LC-MS/MS is largely limited. To overcome this technical obstacle of derivatization-based LC-MS and increase submetabolome coverage, we proposed an extendable all-in-one injection LC-MS/MS strategy. 5-dimethylamino-naphthalene-1-sulfonyl chloride (Dns-Cl)/5-diethylamino-naphthalene-1-sulfonyl chloride (Dens-Cl) and 5-dimethylamino-naphthalene-1-sulfonyl piperazine (Dns-PP)/5-diethylamino-naphthalene-1-sulfonyl piperazine (Dens-PP) were used as twins labeling reagents for amino/phenol and carboxyl submetabolomes, respectively. "Series Mode" and "Parallel Mode" were proposed and investigated using eight representative standards with the consideration of interaction between different derivatization systems, time-consumption, and extendability. As a result, we found that "Series Mode" led to yield reduction, while "Parallel Mode" gave identical results with those of individual derivatization. Finally, a "Parallel Mode" was chosen to develop an extendable all-in-one injection twin derivatization LC-MS/MS strategy to quantify eighty metabolites assigned to five classes of microbial metabolites, including polyamines, amino acids, indole derivatives, bile acids, and free fatty acids. This well-validated method quantified 67 metabolites absolutely and discovered additional 40 differential metabolites compared with the untargeted method in rat serum from irinotecan (CPT-11)-induced gastrointestinal toxicity model.

Polyamines and microbiota in bicuspid and tricuspid aortic valve aortopathy.

Polyamines are small aliphatic cationic molecules synthesized via a highly regulated pathway and involved in general molecular and cellular phenomena. Both mammalian cells and microorganisms synthesize polyamines, and both sources may contribute to the presence of polyamines in the circulation. The dominant location for microorganisms within the body is the gut. Accordingly, the gut microbiota probably synthesizes most of the polyamines in the circulation in addition to those produced by the mammalian host cells. Polyamines are mandatory for cellular growth and proliferation. Established evidence suggests that the polyamine spermidine prolongs lifespan and improves cardiovascular health in animal models and humans through both local mechanisms, involving improved cardiomyocyte function, and systemic mechanisms, including increased NO bioavailability and reduced systemic inflammation. Higher levels of polyamines have been detected in non-dilated aorta of patients affected by bicuspid aortic valve congenital malformation, an aortopathy associated with an increased risk for thoracic ascending aorta aneurysm. In this review, we discuss metabolism of polyamines and their potential effects on vascular smooth muscle and endothelial cell function in vascular pathology of the thoracic ascending aorta associated with bicuspid or tricuspid aortic valve.

A Plasma Metabolomic Signature of the Exfoliation Syndrome Involves Amino Acids, Acylcarnitines, and Polyamines.

Purpose: To determine the plasma metabolomic signature of the exfoliative syndrome (XFS), the most common cause worldwide of secondary open-angle glaucoma. Methods: We performed a targeted metabolomic study, using the standardized p180 Biocrates Absolute IDQ p180 kit with a QTRAP 5500 mass spectrometer, to compare the metabolomic profiles of plasma from individuals with XFS (n = 16), and an age- and sex-matched control group with cataract (n = 18). Results: A total of 151 metabolites were detected correctly, 16 of which allowed for construction of an OPLS-DA model with a good predictive capability (Q2cum = 0.51) associated with a low risk of over-fitting (permQ2 = -0.48, CV-ANOVA P-value <0.001). The metabolites contributing the most to the signature were octanoyl-carnitine (C8) and decanoyl-carnitine (C10), the branched-chain amino acids (i.e., isoleucine, leucine, and valine), and tyrosine, all of which were at higher concentrations in the XFS group, whereas spermine and spermidine, together with their precursor acetyl-ornithine, were at lower concentrations than in the control group. Conclusions: We identified a significant metabolomic signature in the plasma of individuals with XFS. Paradoxically, this signature, characterized by lower concentrations of the neuroprotective spermine and spermidine polyamines than in controls, partially overlaps the plasma metabolomic profile associated with insulin resistance, despite the absence of evidence of insulin resistance in XFS.

Polyamine patterns in plasma of patients with systemic lupus erythematosus and fever.

Systemic lupus erythematosus (SLE) is a systemic autoimmune disease with various clinical manifestations and serologic markers. In this study, we analyzed nine polyamine (PA) profiles of plasma from patients with SLE and healthy controls (HCs), and the relationship between the PA profiles and disease activity. PA alterations in plasma of 44 patients with SLE and fever were investigated using gas chromatography mass spectrometry (GC-MS) in selected ion monitoring mode using N-ethoxycarbonyl/ N-pentafluoropropionyl derivatives, and compared with those of 43 HCs. Patients with SLE and HCs showed differences in five of nine PA profiles. Among five changed PA levels, four PAs, namely N1-acetylcadaverine, spermidine, N1-acetylspermidine, and spermine, were dramatically decreased. However, the level of cadaverine was increased in patients with SLE. In the partial correlation with PA profiles and disease activity markers of SLE, several disease activity markers and nutritional markers were correlated with cadaverine, spermidine, and N 8-acetylspermidine. Thus, our results provide a comprehensive understanding of the relationship between PA metabolomics and disease activity markers in patients with SLE.