Metabonomic analysis of rat urine 1H magnetic resonance spectra based on different normalization methods / 中南大学学报(医学版)

Objective To study metabonomics in the urine of rats of different genders by magnetic resonance (MR) with 2 normalization methods. Methods Different normalization methods such as mean-centering not scaling (Ctr) and unit variance scaling (UV) were used before orthogonal to partial least squares discriminant analysis(OPLS-DA). Distinguished metabolites in the urine of different gender rats were analyzed by calculating the correlation coefficients. Results The data normalized by Ctr before OPLS-DA analysis revealed high degree conception metabolites in the urine such as valine, alanine, acetate, ornithine, aminohippurate, phenylethylamine, cytosine, citrate, dimethylamine, allantoin, methylamine, fumarate and one unknown metabolite whose chemical shift was δ4.14. Data normalized by UV before OPLS-DA analysis revealed the above 12 high degree conception metabolites except citrate, and also low degree conception metabolites such as thiamine, creatinine, formate and one unknown metabolite whose chemical shift was δ2.92.Conclusion Unit variance scaling is a more effective normalization method in metabonomic analysis.

1H-MRS metabonomic analysis of plasma samples of esophageal cancer patients based on different pattern recognition / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To analyze the metabonomic (1)H-MRS of plasma samples from patients with esophageal cancer and healthy controls applying different pattern recognition methods, and to explore the potential of application of (1)H-MR-based metabonomics in clinical research.</p><p><b>METHODS</b>(1)H-MR was performed on plasma samples from 109 EC patients and 50 health controls to analyze the metabonomic variation between EC patients and healthy subjects and the corresponding (1)H-MRS were recorded on Varian Unity ANOVA 600 MHz to perform principal components analysis (PCA), partial least squares discriminant analysis (PLS-DA), orthogonal partial least squares discriminant analysis (OPLS-DA), respectively.</p><p><b>RESULTS</b>OPLS-DA analysis could correctly separate almost all the plasma samples from EC patients and health controls, better than both the PCA and PLS-DA. The plasma levels of leucine, alanine, isoleucine, valine, glycoprotein, lactate, acetone, acetate, choline, isobutyrate, unsaturated lipid, VLDL, LDL, 1-methylhistidine were significantly decreased in EC patients (r total > 0.27, P < 0.05), while that of dimethylamine, α-glucose, β-glucose, citric acid increased in the EC patients (r total < -0.27, P < 0.05).</p><p><b>CONCLUSIONS</b>The analysis of metabonomic (1)H-MRS of plasma samples by OPLS-DA method can eliminate the influence of non-experimental factors and decrease the heterogeneity of samples. It is useful and of great potential for application in clinical diagnosis and research of esophageal cancer.</p>

Metabonomic variation of esophageal cancer within different ethnic groups in Xinjiang, China / 中华预防医学杂志

<p><b>OBJECTIVE</b>To investigate the metabonomic variation between patients with esophageal cancer (EC) and healthy controls, and to analyze the variation between patients with EC.</p><p><b>METHODS</b>H-MR and orthogonal partial least-squares discriminant analysis (OPLS-DA) was performed on 108 plasma specimens from EC patients and 50 health controls, and the metabonomic variation between patients with EC and healthy controls analyzed.</p><p><b>RESULTS</b>OPLS-DA analysis might correctly separate all plasma specimens from health controls and patients with EC, leucine (0.0043 +/- 0.0006, 0.0040 +/- 0.0006), alanine (0.0039 +/- 0.0007, 0.0033 +/- 0.0006), isoleucine (0.0067 +/- 0.0010, 0.0063 +/- 0.0009), valine (0.0037 +/- 0.0005, 0.0035 +/- 0.0006), glycoprotein (0.0123 +/- 0.0043, 0.0102 +/- 0.0022), lactate (0.0342 +/- 0.0113, 0.0258 +/- 0.0085), acetone (0.0027 +/- 0.0023, 0.0017 +/- 0.0008), acetate (0.0007 +/- 0.0001, 0.0006 +/- 0.0001), choline (0.0035 +/- 0.0006, 0.0029 +/- 0.0007), isobutyrate (0.0020 +/- 0.0004, 0.0018 +/- 0.0003), unsaturated lipid (0.0072 +/- 0.0013, 0.0059 +/- 0.0018), VLDL (0.1209 +/- 0.0589, 0.0879 +/- 0.0269), LDL (0.0885 +/- 0.0328, 0.0785 +/- 0.0288), 1-methylhistidine (0.0005 +/- 0.0001, 0.0004 +/- 0.0005) decreased in EC patient' s plasma with statistical significance (r total > 0.27, P < 0.05), dimethylamine (0.0004 +/- 0.0001, 0.0005 +/- 0.0001), alpha-glucose (0.0079 +/- 0.0013, 0.0081 +/- 0.0016), 3-glucose (0.0139 +/- 0.0024, 0.0142 +/- 0.0029), citric acid (0.0044 +/- 0.0008, 0.0106 +/- 0.0058) increase in the EC patient's plasma (r total < -0.27, P < 0.05). There were clear variation between Han and Kazak patients, alanine (0.0031 +/- 0.0005,0.0029 +/- 0.0004), glutamine (0.0010 +/- 0.0001, 0.0009 +/- 0.0001), tyrosine (0.0009 +/- 0.0001, 0.0008 +/- 0.0001), 1-methylhistidine (0.0005 +/- 0.0001, 0.0004 +/- 0.0001) increased in the Han patients (r > 0.35, P> 0.05), carnitine (0.0028 +/- 0.0006) was higher in Kazak patients than in Han patients (0.0025 +/- 0.0004), which had statistical significance (r = - 0.40, P < 0.05). Unsaturated lipid (0.0059 +/- 0.0018, 0.0047 +/- 0.0011), isoleucine (0.0062 +/- 0.0011, 0.0058 +/- 0.0007), alanine (0. 0032 +/- 0.0007, 0.0028 +/- 0.0004), glycoprotein (0.0096 +/- 0.0019, 0.0086 +/- 0.0011), glutamine (0.0011 +/- 0.0001, 0.0009 +/- 0.0001), tyrosine (0.0009 +/- 0.0001, 0.0008 +/- 0.0001), 1-methylhistidine (0.0005 +/- 0.0001, 0.0004 +/- 0.0001) were increased in Uygur patients as compared with Kazak patients, having statistical significance (r > 0.33, P < 0.05), carnitine (0.0027 +/- 0.0005) was higher in Kazak patients than in Uygur patients (0.0025 +/- 0.0004) (r = - 0.36, P < 0.05).</p><p><b>CONCLUSION</b>The results indicate that 1H-MR spectra of plasma analyzed by OPLS-DA statistical methods might completely separate the EC patients from health controls. The metabonomic approach should be helpful in screening of EC patients.</p>