Browsing by Author "Vogel, Hans J"

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    A quantitative multimodal metabolomic assay for colorectal cancer
    (2018-01-04) Farshidfar, Farshad; Kopciuk, Karen A; Hilsden, Robert; McGregor, S. E; Mazurak, Vera C; Buie, W. D; MacLean, Anthony; Vogel, Hans J; Bathe, Oliver F
    Abstract Background Early diagnosis of colorectal cancer (CRC) simplifies treatment and improves treatment outcomes. We previously described a diagnostic metabolomic biomarker derived from semi-quantitative gas chromatography-mass spectrometry. Our objective was to determine whether a quantitative assay of additional metabolomic features, including parts of the lipidome could enhance diagnostic power; and whether there was an advantage to deriving a combined diagnostic signature with a broader metabolomic representation. Methods The well-characterized Biocrates P150 kit was used to quantify 163 metabolites in patients with CRC (N = 62), adenoma (N = 31), and age- and gender-matched disease-free controls (N = 81). Metabolites included in the analysis included phosphatidylcholines, sphingomyelins, acylcarnitines, and amino acids. Using a training set of 32 CRC and 21 disease-free controls, a multivariate metabolomic orthogonal partial least squares (OPLS) classifier was developed. An independent set of 28 CRC and 20 matched healthy controls was used for validation. Features characterizing 31 colorectal adenomas from their healthy matched controls were also explored, and a multivariate OPLS classifier for colorectal adenoma could be proposed. Results The metabolomic profile that distinguished CRC from controls consisted of 48 metabolites (R2Y = 0.83, Q2Y = 0.75, CV-ANOVA p-value < 0.00001). In this quantitative assay, the coefficient of variance for each metabolite was <10%, and this dramatically enhanced the separation of these groups. Independent validation resulted in AUROC of 0.98 (95% CI, 0.93–1.00) and sensitivity and specificity of 93% and 95%. Similarly, we were able to distinguish adenoma from controls (R2Y = 0.30, Q2Y = 0.20, CV-ANOVA p-value = 0.01; internal AUROC = 0.82 (95% CI, 0.72–0.93)). When combined with the previously generated GC-MS signatures for CRC and adenoma, the candidate biomarker performance improved slightly. Conclusion The diagnostic power for metabolomic tests for colorectal neoplasia can be improved by utilizing a multimodal approach and combining metabolites from diverse chemical classes. In addition, quantification of metabolites enhances separation of disease-specific metabolomic profiles. Our future efforts will be focused on developing a quantitative assay for the metabolites comprising the optimal diagnostic biomarker.
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    Binding of smoothelin-like 1 to tropomyosin and calmodulin is mutually exclusive and regulated by phosphorylation
    (2017-03-21) Ulke-Lemée, Annegret; Sun, David H; Ishida, Hiroaki; Vogel, Hans J; MacDonald, Justin A
    Abstract Background The smoothelin-like 1 protein (SMTNL1) can associate with tropomyosin (Tpm) and calmodulin (CaM), two proteins essential to the smooth muscle contractile process. SMTNL1 is phosphorylated at Ser301 by protein kinase A during calcium desensitization in smooth muscle, yet the effect of SMTNL1 phosphorylation on Tpm- and CaM-binding has yet to be investigated. Results Using pull down studies with Tpm-Sepharose and CaM-Sepharose, we examined the interplay between Tpm binding, CaM binding, phosphorylation of SMTNL1 and calcium concentration. Phosphorylation greatly enhanced the ability of SMTNL1 to associate with Tpm in vitro; surface plasmon resonance yielded a 10-fold enhancement in K D value with phosphorylation. The effect on CaM binding is more complex and varies with the availability of calcium. Conclusions Combining both CaM and Tpm with SMTNL1 shows that the binding to both is mutually exclusive.
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    Integration of metabolic and inflammatory mediator profiles as a potential prognostic approach for septic shock in the intensive care unit
    (Critical Care, BioMed Central, 2015-01-15) Mickiewicz, Beata; Tam, Patrick; Jenne, Craig N; Leger, Caroline; Wong, Josee; Winston, Brent W; Doig, Christopher; Kubes, Paul; Vogel, Hans J
    Introduction Septic shock is a major life-threatening condition in critically ill patients and it is well known that early recognition of septic shock and expedient initiation of appropriate treatment improves patient outcome. Unfortunately, to date no single compound has shown sufficient sensitivity and specificity to be used as a routine biomarker for early diagnosis and prognosis of septic shock in the intensive care unit (ICU). Therefore, the identification of new diagnostic tools remains a priority for increasing the survival rate of ICU patients. In this study, we have evaluated whether a combined nuclear magnetic resonance spectroscopy-based metabolomics and a multiplex cytokine/chemokine profiling approach could be used for diagnosis and prognostic evaluation of septic shock patients in the ICU. Methods Serum and plasma samples were collected from septic shock patients and ICU controls (ICU patients with the systemic inflammatory response syndrome but not suspected of having an infection). 1H Nuclear magnetic resonance spectra were analyzed and quantified using the targeted profiling methodology. The analysis of the inflammatory mediators was performed using human cytokine and chemokine assay kits. Results By using multivariate statistical analysis we were able to distinguish patient groups and detect specific metabolic and cytokine/chemokine patterns associated with septic shock and its mortality. These metabolites and cytokines/chemokines represent candidate biomarkers of the human response to septic shock and have the potential to improve early diagnosis and prognosis of septic shock. Conclusions Our findings show that integration of quantitative metabolic and inflammatory mediator data can be utilized for the diagnosis and prognosis of septic shock in the ICU.
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    Metabolomic Biomarkers for Colorectal Cancer
    (2016) Farshidfar, Farshad; Bathe, Oliver F.; Vogel, Hans J; Kopciuk, Karen A; Hilsden, Robert; Buie, W. Donald
    Colorectal cancer (CRC) is the second most common cancer in the North America. It is also a huge burden for society. Remarkable efforts have been and are being made to improve CRC diagnosis, to enhance the effectiveness of treatments, and to eventually improve the outcome of these patients. Metabolomic profiling, as a method for describing metabolic state and alterations in the molecular constituents and capable of yielding unique and invaluable information about tumor biology, has been employed. Using a range of spectroscopy and mass spectrometry techniques, we have sought to characterize the changes in the serum metabolome that appear as a result of malignant and pre-malignant lesions in the colon and rectum. In Chapter 2, Application of gas chromatography-mass spectrometry (GC-MS) and nuclear magnetic resonance (NMR) spectroscopy for staging CRC is described. Chapter 3 describes a larger study of 320 CRC and 31 colorectal adenoma cases as well as their matching controls by GC-MS, which led to the identification of validated metabolomic signature for identification of CRC and a proposed signature for identification of colorectal adenoma. In chapter 4, an effort for quantitative profiling of 62 CRC cases and 31 colorectal adenomas and their matching controls by tandem mass spectrometry is illustrated, and a validated quantitative signature for diagnosis of CRC is reported. Chapter 5 is dedicated to studying the prognostic value of metabolomic profiling in colorectal liver metastatic patients, and a novel workflow for estimation of recurrence risk using high-dimensional data is proposed. Challenges and pitfalls confronted in different steps of the project were addressed when possible by the use of available methods. Where no reliable method was available, we made an effort to develop one. This thesis, therefore, is focused on the metabolomic characterization of CRC and the adaptation of this knowledge for the development of clinically valuable biomarkers.
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    Plasma lipid profiling for the prognosis of 90-day mortality, in-hospital mortality, ICU admission, and severity in bacterial community-acquired pneumonia (CAP)
    (2020-07-27) Banoei, Mohammad M; Vogel, Hans J; Weljie, Aalim M; Yende, Sachin; Angus, Derek C; Winston, Brent W
    Abstract Introduction Pneumonia is the most common cause of mortality from infectious diseases, the second leading cause of nosocomial infection, and the leading cause of mortality among hospitalized adults. To improve clinical management, metabolomics has been increasingly applied to find specific metabolic biopatterns (profiling) for the diagnosis and prognosis of various infectious diseases, including pneumonia. Methods One hundred fifty bacterial community-acquired pneumonia (CAP) patients whose plasma samples were drawn within the first 24 h of hospital admission were enrolled in this study and separated into two age- and sex-matched cohorts: non-survivors (died ≤ 90 days) and survivors (survived > 90 days). Three analytical tools, 1H-NMR spectroscopy, GC-MS, and targeted DI-MS/MS, were used to prognosticate non-survivors from survivors by means of metabolic profiles. Results We show that quantitative lipid profiling using DI-MS/MS can predict the 90-day mortality and in-hospital mortality among patients with bacterial CAP compared to 1H-NMR- and GC-MS-based metabolomics. This study showed that the decreased lysophosphatidylcholines and increased acylcarnitines are significantly associated with increased mortality in bacterial CAP. Additionally, we found that decreased lysophosphatidylcholines and phosphatidylcholines (> 36 carbons) and increased acylcarnitines may be used to predict the prognosis of in-hospital mortality for bacterial CAP as well as the need for ICU admission and severity of bacterial CAP. Discussion This study demonstrates that lipid-based plasma metabolites can be used for the prognosis of 90-day mortality among patients with bacterial CAP. Moreover, lipid profiling can be utilized to identify patients with bacterial CAP who are at the highest risk of dying in hospital and who need ICU admission as well as the severity assessment of CAP.
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    Plasma metabolomics for the diagnosis and prognosis of H1N1 influenza pneumonia
    (2017-04-19) Banoei, Mohammad M; Vogel, Hans J; Weljie, Aalim M; Kumar, Anand; Yende, Sachin; Angus, Derek C; Winston, Brent W
    Abstract Background Metabolomics is a tool that has been used for the diagnosis and prognosis of specific diseases. The purpose of this study was to examine if metabolomics could be used as a potential diagnostic and prognostic tool for H1N1 pneumonia. Our hypothesis was that metabolomics can potentially be used early for the diagnosis and prognosis of H1N1 influenza pneumonia. Methods 1H nuclear magnetic resonance spectroscopy and gas chromatography-mass spectrometry were used to profile the metabolome in 42 patients with H1N1 pneumonia, 31 ventilated control subjects in the intensive care unit (ICU), and 30 culture-positive plasma samples from patients with bacterial community-acquired pneumonia drawn within the first 24 h of hospital admission for diagnosis and prognosis of disease. Results We found that plasma-based metabolomics from samples taken within 24 h of hospital admission can be used to discriminate H1N1 pneumonia from bacterial pneumonia and nonsurvivors from survivors of H1N1 pneumonia. Moreover, metabolomics is a highly sensitive and specific tool for the 90-day prognosis of mortality in H1N1 pneumonia. Conclusions This study demonstrates that H1N1 pneumonia can create a quite different plasma metabolic profile from bacterial culture-positive pneumonia and ventilated control subjects in the ICU on the basis of plasma samples taken within 24 h of hospital/ICU admission, early in the course of disease.
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    Serum metabolomic profile as a means to distinguish stage of colorectal cancer
    (BioMed Central, 2012-05-14) Bathe, Oliver F.; Farshidfar, Farshad; Weljie, Aalim M.; Kopciuk, Karen; Buie, W Don; MacLean, Anthony; Dixon, Elijah; Sutherland, Francis R; Molckovsky, Andrea; Vogel, Hans J
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    Simultaneous binding of the N- and C-terminal cytoplasmic domains of aquaporin 4 to calmodulin
    (Elsevier, 2022-01) Ishida, Hiroaki; Vogel, Hans J; Conner, Alex C; Kitchen, Philip; Bill, Roslyn M; MacDonald, Justin A
    Aquaporin 4 (AQP4) is a water transporting, transmembrane channel protein that has important regulatory roles in maintaining cellular water homeostasis. Several other AQP proteins exhibit calmodulin (CaM)-binding properties, and CaM has recently been implicated in the cell surface localization of AQP4. The objective of the present study was to assess the CaM-binding properties of AQP4 in detail. Inspection of AQP4 revealed two putative CaM-binding domains (CBDs) in the cytoplasmic N- and C-terminal regions, respectively. The Ca2+-dependent CaM-binding properties of AQP4 CBD peptides were assessed using fluorescence spectroscopy, isothermal titration calorimetry, and two-dimensional 1H, 15N-HSQC NMR with 15N-labeled CaM. The N-terminal CBD of AQP4 predominantly interacted with the N-lobe of CaM with a 1:1 binding ratio and a Kd of 3.4 μM. The C-terminal AQP4 peptide interacted with both the C- and N-lobes of CaM (2:1 binding ratio; Kd1: 3.6 μM, Kd2: 113.6 μM, respectively). A recombinant AQP4 protein domain (recAQP4CT, containing the entire cytosolic C-terminal sequence) bound CaM in a 1:1 binding mode with a Kd of 6.1 μM. A ternary bridging complex could be generated with the N- and C-lobes of CaM interacting simultaneously with the N- and C-terminal CBD peptides. These data support a unique adapter protein binding mode for CaM with AQP4.