Changes in the concentration of bone turnover markers in men after maximum intensity exercise.

Background: Physical activity is an important factor in modelling the remodelling and metabolism of bone tissue. The aim of the study was to evaluate the changes in indices demonstrating bone turnover in men under the influence of maximum-intensity exercise. Methods: The study involved 33 men aged 20-25, divided into two groups: experimental (n = 15) and control (n = 18). People training medium- and long-distance running were assigned to the experimental group, and non-training individuals to the control. Selected somatic, physiological and biochemical indices were measured. The level of aerobic fitness was determined using a progressively increasing graded test (treadmill test for subjective fatigue). Blood samples for determinations were taken before the test and 60 minutes after its completion. The concentration of selected bone turnover markers was assessed: bone fraction of alkaline phosphatase (b-ALP), osteoclacin (OC), N-terminal cross-linked telopeptide of the alpha chain of type I collagen (NTx1), N-terminal propeptide of type I progolagen (PINP), osteoprotegerin (OPG). In addition, the concentration of 25(OH)D3 prior to the stress test was determined. Additionally, pre and post exercise, the concentration of lactates in the capillary blood was determined. Results: When comparing the two groups, significant statistical differences were found for the mean level of: 25(OH)D3 (p = 0.025), b-ALP (p < 0.001), OC (p = 0.004) and PINP (p = 0.029) prior to the test. On the other hand, within individual groups, between the values pre and post the stress test, there were statistically significant differences for the average level of: b-ALP (p < 0.001), NTx1 (p < 0.001), OPG (p = 0.001) and PINP (p = 0.002). Conclusion: A single-session maximum physical effort can become an effective tool to initiate positive changes in bone turnover markers.

Long-Term Changes of Urinary Exosomal Peptide Levels After Thyroidectomy in Patients with Thyroid Cancer: A Prospective Observational Study.

Background: The recurrence rate of thyroid cancer can be as high as 30%. The purpose of this study was to examine changes of urine exosomal peptide levels after thyroidectomy in patients with thyroid cancer to determine if levels can predict the risk of recurrence. Methods: Patients >20 years old as newly diagnosed with papillary thyroid cancer who had received a thyroidectomy were recruited. Urine samples were collected at 12 months after enrollment to the study, and 1 year later. Urine exosomes containing different peptides were identified and compared. Results: A total of 70 patients were enrolled in the study, and were classified by the interval between surgery and enrollment: 42 patients with < 5 years between surgery and enrollment, 14 patients between 5-10 years, and 14 patients longer than 10 years. No recurrence was observed in any patient during the 2 years after enrollment. No significant differences were found in the levels of serum proteins or urine exosomal peptides between groups, or between intervals. Known risk factors for high-risk thyroid cancer had only a mild correlation with serum protein levels and urine exosomal peptides. Conclusion: Our study revealed the long-term basal fluctuation ranges of serum proteins and urine exosomal peptides in patients with thyroid cancer who underwent thyroidectomy. For high-risk patients after thyroidectomy, concentrations of serum proteins or urine exosomal peptides within the ranges may indicate there is a lower risk of thyroid cancer recurrence during long-term follow-up. Trial Registration: ClinicalTrials.gov: NCT03488134.

Investigating protease-mediated peptides of inflammation and tissue remodeling as biomarkers associated with flares in psoriatic arthritis.

BACKGROUND: Psoriatic arthritis (PsA) is an inflammatory arthritis associated with psoriasis. PsA disease involves flares, which are associated with increased joint inflammation and tissue remodeling. There is a need for identifying biomarkers related to PsA disease activity and flares to improve the management of PsA patients and decrease flares. The tissue turnover imbalance that occurs during the inflammatory and fibro-proliferative processes during flares leads to an increased degradation and/or reorganization of the extracellular matrix (ECM), where increased proteolysis plays a key role. Hence, protease-mediated fragments of inflammatory and tissue-remodeling components could be used as markers reflecting flares in PsA patients. METHODS: A broad panel of protease-mediated biomarkers reflecting inflammation and tissue remodeling was measured in serum and synovial fluid (SF) obtained from PsA patients experiencing flares (acutely swollen joint[s], PsA-flare). In serum, biomarker levels assessed in PsA-flare patients were compared to controls and in early-diagnosed PsA patients not experiencing flares (referred to as PsA without flare). Furthermore, the biomarker levels assessed in SF from PsA-flare patients were compared to the levels in SF of osteoarthritis (OA) patients. RESULTS: In serum, levels of the PRO-C3 and C3M, reflecting formation and degradation of the interstitial matrix, were found significantly elevated in PsA-flare compared to controls and PsA without flare. The remodeling marker of the basement membrane, PRO-C4, was significantly elevated in PsA-flare compared to PsA without flare. The inflammation and immune cell activity related markers, CRPM, VICM, and CPa9-HNE were significantly elevated in PsA-flare patients compared to controls and PsA without flare. In addition, VICM (AUC = 0.71), CPa9-HNE (AUC = 0.89), CRPM (AUC = 0.76), and PRO-C3 (AUC = 0.86) showed good discriminatory performance for separating PsA-flare from PsA without flare. In SF, the macrophage activity marker, VICM, was significantly elevated whereas the type II collagen formation marker, PRO-C2, was significantly reduced in the PsA-flare compared to OA. The combination of five serum markers reflecting type III and IV collagen degradation (C3M and C4M, respectively), type III and VI collagen formation (PRO-C3 and PRO-C6, respectively), and neutrophil activity (CPa9-HNE) showed an excellent discriminatory performance (AUC = 0.98) for separating PsA-flare from PsA without flares. CONCLUSIONS: The serum biomarker panel of C3M, C4M, PRO-C3, PRO-C6, and CPa9-HNE reflecting synovitis, enthesitis, and neutrophil activity may serve as novel tool for quantitatively monitoring flares in PsA patients.

Association between CTX-1 and Fibulin-1 Serum Levels with Pathogenesis of Multiple Myeloma Cancer.

BACKGROUND: Multiple myeloma (MM) is the second most prevalent blood cancer after non-Hodgkin lymphoma. It is identified by the excessive production of abnormal monoclonal immunoglobulins, which can result in various clinical symptoms such as destructive bone lesions, renal dysfunction, anemia, and immunodeficiency. The current study aims to evaluate the serum levels of carboxy-terminal collagen crosslinks 1 (CTX-1), Fibulin-1, vitamin D3, LDH, and albumin in MM patients and their significance for early diagnosis. MATERIALS AND METHODS: This study included 30 healthy controls (11 males, 19 females) and 60 patients with multiple myeloma (37 males and 23 females), aged between 40-60 years. Five-milliliter blood samples were collected and stored at -20°C. Afterward, enzyme-linked immunosorbent assay (ELISA) kits were used to estimate the concentrations of CTX-1, Fibulin-1, and vitamin D3. Additionally, LDH and albumin levels were determined using the automated biochemistry analyzer. RESULTS: This study revealed that the majority of patients with multiple myeloma are between the ages of 51 and 60 years. The serum concentrations of CTX-1, Fibulin-1, and LDH were significantly increased in the multiple myeloma patients compared to the healthy control group. In contrast, the serum level of vitamin D3 was significantly decreased in patients with MM. CONCLUSION: Our results indicate that the incidence of multiple myeloma is higher in males than in females. Additionally, the serum concentrations of CTX-1 and Fibulin-1 were significantly higher in the multiple myeloma patients compared to the healthy control group, indicating their potential for early detection and as therapeutic targets.

PoCOsteo: generic novel platform for bone turnover marker measurement & monitoring.

Despite the increasing efforts in improving bone health assessments, current diagnostics suffer from critical shortcomings. The present article therefore describes a multiplex label-free immunosensor designed and validated for the assessment of two bone turnover markers (BTMs), namely beta isomerized C-terminal telopeptide of type I collagen (CTx) and Procollagen I Intact N-Terminal (PINP), the combination of which is needed to illustrate an accurate overview of bone health. The immunosensor was then tested outside and inside of a microsystem, with the aim of becoming compatible with a point of care system fabricated for automated assessment of these biomarkers later-on at patient side. Custom-made monoclonal antibodies were specifically designed for this purpose in order to guarantee the selectivity of the immunosensor. In the final platform, a finger prick blood sample is introduced into the microfluidic manifolds without any need for sample preparation step, making the tool suitable for near patient and outside of the central laboratory applications. The platform was exploited in 30 real blood samples with the results validated using electrochemiluminescence immunoassay. The results revealed the platform was capable of measuring the target analyte with high sensitivity and beyond the recommended clinical reference range for each biomarker (CTx: 104-1028 ng L-1 and PINP: 16-96 µg L-1, correspondingly). They also showed the platform to have a limit of detection of 15 (ng L-1) and 0.66 (µg L-1), a limit of quantification of 49 (ng L-1) and 2.21 (µg L-1), and an inter- and intra-assay coefficient of variance of 5.39-6.97% and 6.81-5.37%, for CTx and PINP respectively, which is comparable with the gold standard. The main advantage of the platform over the state-of-the art was the capability of providing the results for two markers recommended for assessing bone health within 15 minutes and without the need for skilled personnel or costly infrastructure.

The role of bone turnover markers in diagnosis, monitoring, and pathological fractures of osteoporosis.

BACKGROUND: We investigated the utility of specific biomarkers-namely, c-terminal telopeptide (CTX), n-telopeptide (NTX), deoxypyridinoline (DPD), and tartrate-resistant acid phosphatase (TRAP)-compared to conventional diagnostic methods. We hy-pothesized that these novel biomarkers could hold substantial value in the diagnosis, treatment, and monitoring of osteoporosis. METHODS: The study was conducted over a three-year period, from January 1, 2020, to January 1, 2023. We enrolled a total of 520 patients aged 50 years or older who had been diagnosed with osteoporosis. Patients undergoing steroid treatments, which are known to contribute to osteoporosis, were excluded from the study. Additionally, we carefully selected and matched a control group consisting of 500 patients based on demographic characteristics relevant to the diagnosis of osteoporosis. This meticulous selection process resulted in a comprehensive cohort comprising 1,020 patients. Throughout the study, patients were closely monitored for a duration of one year to track the occurrence of pathological fractures and assess their overall prognosis. RESULTS: As a result of our rigorous investigation, we identified CTX, NTX, DPD, and TRAP as pivotal biomarkers that play a crucial role in evaluating bone health, monitoring treatment effectiveness, and detecting pathological fractures in the context of osteoporosis. CONCLUSION: Our study underscores the significance of these biomarkers in advancing the diagnosis and management of osteo-porosis, offering valuable insights into the disease's progression and treatment outcomes.

Serologic Response to the Epstein-Barr Virus Peptidome and the Risk for Multiple Sclerosis.

Importance: It remains unclear why only a small proportion of individuals infected with the Epstein-Barr virus (EBV) develop multiple sclerosis (MS) and what the underlying mechanisms are. Objective: To assess the serologic response to all EBV peptides before the first symptoms of MS occur, determine whether the disease is associated with a distinct immune response to EBV, and evaluate whether specific EBV epitopes drive this response. Design, Setting, and Participants: In this prospective, nested case-control study, individuals were selected among US military personnel with serum samples stored in the US Department of Defense Serum Repository. Individuals with MS had serum collected at a median 1 year before onset (reported to the military in 2000-2011) and were matched to controls for age, sex, race and ethnicity, blood collection, and military branch. No individuals were excluded. The data were analyzed between September 1, 2022, and August 31, 2023. Exposure: Antibodies (enrichment z scores) to the human virome measured using VirScan (phage-displayed immunoprecipitation and sequencing). Main Outcome and Measure: Rate ratios (RRs) for MS for antibodies to 2263 EBV peptides (the EBV peptidome) were estimated using conditional logistic regression, adjusting for total anti-EBV nuclear antigen 1 (EBNA-1) antibodies, which have consistently been associated with a higher MS risk. The role of antibodies against other viral peptides was also explored. Results: A total of 30 individuals with MS were matched with 30 controls. Mean (SD) age at sample collection was 27.8 (6.5) years; 46 of 60 participants (76.7%) were male. The antibody response to the EBV peptidome was stronger in individuals with MS, but without a discernible pattern. The antibody responses to 66 EBV peptides, the majority mapping to EBNA antigens, were significantly higher in preonset sera from individuals with MS (RR of highest vs lowest tertile of antibody enrichment, 33.4; 95% CI, 2.5-448.4; P for trend = .008). Higher total anti-EBNA-1 antibodies were also associated with an elevated MS risk (top vs bottom tertile: RR, 27.6; 95% CI, 2.3-327.6; P for trend = .008). After adjusting for total anti-EBNA-1 antibodies, risk estimates from most EBV peptides analyses were attenuated, with 4 remaining significantly associated with MS, the strongest within EBNA-6/EBNA-3C, while the association between total anti-EBNA-1 antibodies and MS persisted. Conclusion and Relevance: These findings suggest that antibody response to EBNA-1 may be the strongest serologic risk factor for MS. No single EBV peptide stood out as being selectively targeted in individuals with MS but not controls. Larger investigations are needed to explore possible heterogeneity of anti-EBV humoral immunity in MS.

Predictors of bone mineral density in patients receiving glucocorticoid replacement for Addison's disease.

PURPOSE: Patients receiving long-term glucocorticoid (GC) treatment are at risk of osteoporosis, while bone effects of substitution doses in Addison's disease (AD) remain equivocal. The project was aimed to evaluate serum bone turnover markers (BTMs): osteocalcin, type I procollagen N-terminal propeptide (PINP), collagen C-terminal telopeptide (CTX), sclerostin, DKK-1 protein, and alkaline phosphatase (ALP) in relation to bone mineral density (BMD) during GC replacement. METHODS: Serum BTMs and hormones were assessed in 80 patients with AD (22 males, 25 pre- and 33 postmenopausal females) on hydrocortisone (HC) substitution for ≥3 years. Densitometry with dual-energy X-ray absorptiometry covered the lumbar spine (LS) and femoral neck (FN). RESULTS: Among BTMs, only PINP levels were altered in AD. BMD Z-scores remained negative except for FN in males. Considering T-scores, osteopenia was found in LS in 45.5% males, 24% young and 42.4% postmenopausal females, while osteoporosis in 9.0%, 4.0% and 21.1%, respectively. Lumbar BMD correlated positively with body mass (p = 0.0001) and serum DHEA-S (p = 9.899 × 10-6). Negative correlation was detected with HC dose/day/kg (p = 0.0320), cumulative HC dose (p = 0.0030), patient's age (p = 1.038 × 10-5), disease duration (p = 0.0004), ALP activity (p = 0.0041) and CTX level (p = 0.0105). However, only age, body mass, ALP, serum CTX, and sclerostin remained independent predictors of LS BMD. CONCLUSION: Standard HC substitution does not considerably accelerate BMD loss in AD patients and their serum BTMs: CTX, osteocalcin, sclerostin, DKK-1, and ALP activity remain within the reference ranges. Independent predictors of low lumbar spine BMD, especially ALP activity, serum CTX and sclerostin, might be monitored during GC substitution.

Postprandial plasma amino acid and appetite responses with ingestion of a novel salmon-derived protein peptide in healthy young adults.

This study assessed postprandial plasma aminoacidemia, glycemia, insulinemia and appetite responses to ingestion of a novel salmon-derived protein peptide (Salmon PP) compared with milk protein isolate (Milk PI). In a randomised, participant-blind crossover design, eleven healthy adults (M = 5, F = 6; mean ± sd age: 22 ± 3 years; BMI: 24 ± 3 kg/m2) ingested 0·3 g/kg/body mass of Salmon PP or Milk PI. Arterialised blood samples were collected whilst fasted and over a 240-min postprandial period. Appetite sensations were measured via visual analogue scales. An ad libitum buffet-style test meal was administered after each trial. The incremental AUC (iAUC) plasma essential amino acid (EAA) response was similar between Salmon PP and Milk PI. The iAUC plasma leucine response was significantly greater following Milk PI ingestion (P < 0·001), whereas temporal and iAUC plasma total amino acid (P = 0·001), non-essential amino acid (P = 0·002), glycine (P = 0·0025) and hydroxyproline (P < 0·001) responses were greater following Salmon PP ingestion. Plasma insulin increased similarly above post-absorptive values following Salmon PP and Milk PI ingestion, whilst plasma glucose was largely unaltered. Indices of appetite were similarly altered following Salmon PP and Milk PI ingestion, and total energy and macronutrient intake during the ad libitum meal was similar between Salmon PP and Milk PI. The postprandial plasma EAA, glycine, proline and hydroxyproline response to Salmon PP ingestion suggest this novel protein source could support muscle and possibly connective tissue adaptive remodelling, which warrants further investigation, particularly as the plasma leucine response to Salmon PP ingestion was inferior to Milk PI.

Effect of vitamin D supplementation or fortification on bone turnover markers in women: a systematic review and meta-analysis.

Vitamin D is a vital indicator of musculoskeletal health, as it plays an important role through the regulation of bone and mineral metabolism. This meta-analysis was performed to investigate the effects of vitamin D supplementation/fortification on bone turnover markers in women. All human randomised clinical trials reported changes in bone resorption markers (serum C-terminal telopeptide of type-I collagen (sCTX) and urinary type I collagen cross-linked N-telopeptide (uNTX)) or bone formation factors (osteocalcin (OC), bone alkaline phosphatase (BALP) and procollagen type-1 intact N-terminal propeptide (P1NP)) following vitamin D administration in women (aged ≥ 18 years) were considered. Mean differences (MD) and their respective 95 % CI were calculated based on fixed or random effects models according to the heterogeneity status. Subgroup analyses, meta-regression models, sensitivity analysis, risk of bias, publication bias and the quality of the included studies were also evaluated. We found that vitamin D supplementation had considerable effect on sCTX (MD: -0·038, n 22) and OC (MD: -0·610, n 24) with high heterogeneity and uNTX (MD: -8·188, n 6) without heterogeneity. Our results showed that age, sample size, dose, duration, baseline vitamin D level, study region and quality of studies might be sources of heterogeneity in this meta-analysis. Subgroup analysis also revealed significant reductions in P1NP level in dose less than 600 µg/d and larger study sample size (>100 participants). Moreover, no significant change was found in BALP level. Vitamin D supplementation/fortification significantly reduced bone resorption markers in women. However, results were inconsistent for bone formation markers.

Comprehensive characterization of protein modifications using mass spectrometry and dry blood spots.

PURPOSE: The main objective of this study is to characterize and analyze modified peptides in DBS samples. This includes deciphering their specific PTMs and understanding their potential impact on the population or disease cohort under study. EXPERIMENTAL DESIGN: Using mass spectrometry-based proteomic approaches, we performed a comprehensive analysis of DBS samples. Our focus was on the identification and quantification of modified peptides. We also took advantage of recent advances in DBS mass spectrometry to ensure accurate detection and quantification. RESULTS: A comprehensive analysis identified 972 modified peptides in DBS samples. Of these, a subset of 211 peptides was consistently present in all samples, highlighting their potential biological importance and relevance. This indicates a diverse spectrum of PTMs in the proteome of DBS samples. CONCLUSIONS AND CLINICAL RELEVANCE: Integration of mass spectrometry and proteomics has revealed a broad spectrum of modified peptides in DBS samples and highlighted their importance in biological processes and disease progression. Accurate detection of these PTMs may be critical for risk stratification and disease management. This study improves the understanding of molecular mechanisms underlying biological processes and disease development, providing important insights for clinical applications.

Changes in bone turnover markers in adolescents with gastroesophageal reflux disease treated with lansoprazole.

Background: Proton pump inhibitors (PPIs) have been suggested to lead to bone resorption, while the effects of PPIs on the bone mineral metabolism in children has received only limited attention in literature to date. The present study investigates whether lansoprazole alters bone turnover markers in adolescents with gastroesophageal reflux disease (GERD). Patients and methods: Included in the study were adolescents aged 16-18 with GERD and a healthy volunteers group. The GERD patient group was treated with lansoprazole 30 mg once daily for eight weeks. The serum calcium, phosphorus, magnesium, alkaline phosphatase (ALP), parathormone (PTH), 25 (OH) vitamin D, osteocalcin and urinary calcium, creatinine, deoxypyridinoline (DPD), collagen type-1 crosslinked C-telopeptide (CTX) and collagen type-1 crosslinked N-telopeptide (NTX) of both groups were studied before and after the end of the treatment. Results: A comparison of the 30 patients with GERD and the 30 volunteers revealed no significant difference in the serum calcium, phosphorus, magnesium, ALP, urinary calcium/creatinine ratio, 25 (OH) vitamin D and PTH levels measured before and after the lansoprazole treatment, while the osteocalcin, DPD, CTX and NTX values were found to be higher after treatment when compared to those at pre- treatment. Conclusions: The results of this study reveal that eight weeks of treatment with 30 mg lansoprazole daily increased the bone turnover markers of CTX, NTX, DPD and osteocalcin in adolescents aged 16-18.

Mapping and Validation of Peptides Differentially Recognized by Antibodies from the Serum of Yellow Fever Virus-Infected or 17DD-Vaccinated Patients.

Yellow Fever disease is caused by the Yellow Fever virus (YFV), an arbovirus from the Flaviviridae family. The re-emergence of Yellow Fever (YF) was facilitated by the increasing urbanization of sylvatic areas, the wide distribution of the mosquito vector, and the low percentage of people immunized in the Americas, which caused severe outbreaks in recent years, with a high mortality rate. Therefore, serological approaches capable of discerning antibodies generated from the wild-type (YFV-WT) strain between the vaccinal strain (YFV-17DD) could facilitate vaccine coverage surveillance, enabling the development of strategies to avoid new outbreaks. In this study, peptides were designed and subjected to microarray procedures with sera collected from individuals infected by WT-YFV and 17DD-YFV of YFV during the Brazilian outbreak of YFV in 2017/2018. From 222 screened peptides, around ten could potentially integrate serological approaches aiming to differentiate vaccinated individuals from naturally infected individuals. Among those peptides, one was synthesized and validated through ELISA.

Alterations in blood proteins in the prodromal stage of bipolar II disorders.

Although early intervention may help prevent the progression of bipolar disorder, there are some controversies over early pharmacological intervention. In this study, we recruited 40 subjects in the prodromal stage of BD-II (BP), according to bipolar at-risk state criteria. We compared the expression of their plasma proteins with that of 48 BD-II and 75 healthy control (HC) to identify markers that could be detected in a high-risk state. The multiple reaction monitoring method was used to measure target peptide levels with high accuracy. A total of 26 significant peptides were identified through analysis of variance with multiple comparisons, of which 19 were differentially expressed in the BP group when compared to the BD-II and HC groups. Two proteins were overexpressed in the BP group; and were related to pro-inflammation and impaired neurotransmission. The other under-expressed peptides in the BP group were related to blood coagulation, immune reactions, lipid metabolism, and the synaptic plasticity. In this study, significant markers observed in the BP group have been reported in patients with psychiatric disorders. Overall, the results suggest that the pathophysiological changes included in BD-II had already occurred with BP, thus justifying early pharmacological treatment to prevent disease progression.

A versatile technique based on surface-enhanced Raman spectroscopy for label-free detection of amino acids and peptide formation in body fluids.

As an effective analytical method, surface-enhanced Raman spectroscopy (SERS) is widely used in the detection of nucleic acids, amino acids, and other biomolecules. However, obtaining the SERS signal of nonaromatic amino acids is still a challenge. In this work, excess sodium borohydride was used as a reducing agent to prevent the surface of silver nanoparticles from being coated with AgO to enable amino acid molecules to reach the surface of silver nano-substrates. Calcium ions were used as aggregators for silver nano-substrates to successfully achieve the label-free and accurate fingerprint determination of various nonaromatic amino acids. Different types of amino acids were distinguished based on the changes in their peak intensity that were obtained using colorless and transparent organic dichloromethane (DCM) as the internal standard. A Raman signal for low-concentration amino acids in body fluids was detected, and the detection limit for tyrosine was 5 ng/mL. Moreover, the physical and chemical properties of peptides and the formation of peptide chains were further analyzed. The proposed method can potentially be applied to protein sequencing.

Icariin attenuates thioacetamide­induced bone loss via the RANKL­p38/ERK­NFAT signaling pathway.

There is an increasing incidence of destructive bone disease caused by osteoclast proliferation. This is characterized by reduced bone mass and imbalance of bone homeostasis. Icariin (ICA), a flavonoid compound isolated from Epimedium, has anti­osteoporosis activity and inhibits the formation of osteoclasts and bone resorption. The purpose of the present study was to investigate the protective effect of ICA on osteoclastic differentiation induced by thioacetamide (TAA) and its possible mechanism in Sprague Dawley (SD) rats. In the present study, SD rats were intraperitoneally injected with TAA (300 mg/kg) for the bone loss model, treated with ICA (600 mg/kg, intragastric gavage) in the ICA group and TAA+ICA group for treatment of bone loss for 6 weeks. Indexes associated with bone metabolism, such as alkaline phosphatase, N­terminal telopeptide of type­I collagen (NTX­I), calcium (Ca), phosphorus (P) and magnesium (Mg) in the serum, were detected. Osteoclast differentiation of femoral tissues was detected by hematoxylin and eosin and tartrate­resistant acid phosphatase staining. The femoral bone mass was evaluated using a three­point bending test and micro computed tomography. Western blotting was used to detect the expression levels of osteoclast­related proteins in each group. In the rats treated with TAA, the serum concentrations of Ca, P and Mg were decreased, the serum concentration of NTX­I was increased, osteoclast differentiation of the femur was increased, femur bone stress and bone mass were decreased and the bone loss and osteoclast formation were reduced after ICA treatment. In addition, ICA inhibited the protein expression of receptor activator of nuclear factor κ­Β ligand (RANKL), receptor activator of nuclear factor κ­B (RANK), p38, ERK, c­Fos and nuclear factor of activated T cells 1 (NFATc1) in the femur of rats treated with TAA. The results suggested that ICA may inhibit osteoclast differentiation by downregulating the RANKL­p38/ERK­NFAT signaling pathway and prevent TAA­induced bone loss. The results are helpful to understand the mechanism of osteoclast differentiation induced by TAA, as well as the antiresorptive activity and molecular mechanism of ICA, and to provide new ideas for the treatment of osteolytic diseases.

Peptide Biomarkers for the Diagnosis of Dengue Infection.

In a world with an increasing population at risk of exposure to arthropod-borne flaviviruses, access to timely and accurate diagnostic tests would impact profoundly on the management of cases. Twenty peptides previously identified using a flavivirus proteome-wide microarray were evaluated to determine their discriminatory potential to detect dengue virus (DENV) infection. This included nine peptides recognized by IgM antibodies (PM peptides) and 11 peptides recognized by IgG antibodies (PG peptides). A bead-based multiplex peptide immunoassay (MPIA) using the Luminex technology was set-up to determine Ab binding levels to each of these peptides in a panel of 323 carefully selected human serum samples. Sera are derived from individuals either infected with different viruses, namely, the four DENV serotypes, Zika virus (ZIKV), yellow fever virus (YFV), chikungunya virus (CHIKV), West Nile virus (WNV) and Human immunodeficiency virus (HIV), or receiving vaccination against YFV, tick-borne encephalitis (TBEV), and Japanese encephalitis virus (JEV). Additionally, a set of healthy controls were included. We targeted a minimum specificity of 80% for all the analysis. The PG-9 peptide had the best sensitivity (73%) when testing DENV sera from acute patients (A-DENV; <8 days since symptom onset). With sera from convalescent DENV patients (C-DENV; >10 days since symptom onset) the FPG-1 peptide was the best seromarker with a sensitivity of 86%. When combining all A-DENV and C-DENV samples, peptides PM-22 and FPG-1 had the best-diagnostic performance with a sensitivity of 60 and 61.1%, and areas under the curve (AUC) of 0.7865 and 0.8131, respectively. A Random forest (RF) algorithm was used to select the best combination of peptides to classify DENV infection at a targeted specificity >80%. The best RF model for PM peptides that included A-DENV and C-DENV samples, reached a sensitivity of 72.3%, while for PG peptides, the best RF models for A-DENV only, C-DENV only and A-DENV + C-DENV reached a sensitivity of 88.9%, 89.1%, and 88.3%, respectively. In conclusion, the combination of multiple peptides constitutes a founding set of seromarkers for the discrimination of DENV infected individuals from other flavivirus infections.

Sclerostin and bone turnover markers response to cycling and running at the same moderate-to-vigorous exercise intensity in healthy men.

BACKGROUND: Recreational cycling is a popular activity which stimulates and improves cardiovascular fitness. The corresponding benefits for bone are unclear. PURPOSE: This study examined the effect of running (high-impact) vs. cycling (low-impact), at the same moderate-to-vigorous exercise intensity, on markers of bone formation (N-terminal propeptide of type I collagen, PINP) and bone resorption (C-telopeptide of type I collagen, CTX-1), a non-collagenous bone remodeling marker (osteocalcin), as well as bone-modulating factors, including parathyroid hormone (PTH), irisin (myokine) and sclerostin (osteokine). METHODS: Thirteen healthy men (23.7 ± 1.0 y) performed two progressive exercise tests to exhaustion (peak VO2) on a cycle ergometer (CE) and on a treadmill (TM). On subsequent separate days, in randomized order, participants performed 30-min continuous running or cycling at 70% heart rate reserve (HRR). Blood was drawn before, immediately post- and 1 h into recovery. RESULTS: PTH transiently increased (CE, 51.7%; TM, 50.6%) immediately after exercise in both exercise modes. Sclerostin levels increased following running only (27.7%). Irisin increased following both running and cycling. In both exercise modes, CTX-1 decreased immediately after exercise, with no significant change in PINP and osteocalcin. CONCLUSION: At the same moderate-to-vigorous exercise intensity, running appears to result in a greater transient sclerostin response compared with cycling, while the responses of bone markers, PTH and irisin are similar. The longer-term implications of this differential bone response need to be further examined.

Targeted Mass Spectrometry Enables Multiplexed Quantification of Immunomodulatory Proteins in Clinical Biospecimens.

Immunotherapies are revolutionizing cancer care, producing durable responses and potentially cures in a subset of patients. However, response rates are low for most tumors, grade 3/4 toxicities are not uncommon, and our current understanding of tumor immunobiology is incomplete. While hundreds of immunomodulatory proteins in the tumor microenvironment shape the anti-tumor response, few of them can be reliably quantified. To address this need, we developed a multiplex panel of targeted proteomic assays targeting 52 peptides representing 46 proteins using peptide immunoaffinity enrichment coupled to multiple reaction monitoring-mass spectrometry. We validated the assays in tissue and plasma matrices, where performance figures of merit showed over 3 orders of dynamic range and median inter-day CVs of 5.2% (tissue) and 21% (plasma). A feasibility study in clinical biospecimens showed detection of 48/52 peptides in frozen tissue and 38/52 peptides in plasma. The assays are publicly available as a resource for the research community.

Effect of Vitamin E Supplement on Bone Turnover Markers in Postmenopausal Osteopenic Women: A Double-Blind, Randomized, Placebo-Controlled Trial.

Vitamin E is a strong anti-oxidative stress agent that affects the bone remodeling process. This study evaluates the effect of mixed-tocopherol supplements on bone remodeling in postmenopausal osteopenic women. A double-blinded, randomized, placebo-controlled trial study was designed to measure the effect of mixed-tocopherol on the bone turnover marker after 12 weeks of supplementation. All 52 osteopenic postmenopausal women were enrolled and allocated into two groups. The intervention group received mixed-tocopherol 400 IU/day, while the control group received placebo tablets. Fifty-two participants completed 12 weeks of follow-up. Under an intention-to-treat analysis, vitamin E produced a significant difference in the mean bone resorption marker (serum C-terminal telopeptide of type I collagen (CTX)) compared with the placebo group (-0.003 ± 0.09 and 0.121 ± 0.15, respectively (p < 0.001)). In the placebo group, the CTX had increased by 35.3% at 12 weeks of supplementation versus baseline (p < 0.001), while, in the vitamin E group, there was no significant change of bone resorption marker (p < 0.898). In conclusion, vitamin E (mixed-tocopherol) supplementation in postmenopausal osteopenic women may have a preventive effect on bone loss through anti-resorptive activity.