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Li Jing and Wang Chengji

Metabolomics was used to explore the effect of exercise intervention on type 2 diabetes. The rat model of type 2 diabetes was induced by an injection of streptozocin (30 mg/kg), after fed with 8-week high-fat diet. The rats were divided into three groups: the control group, the diabetic model group (DM) and the diabetes + exercise group (DME). After exercise for 10 weeks, blood samples were collected to test biomedical indexes, and 24-h urine samples were collected for the metabolomics experiment. In the DME group, fasting blood glucose (FBG), both total cholesterol (TC) and total plasma triglycerides (TG), were decreased significantly, compared with those in the DM group. Based on gas chromatography-mass spectrometry (GC/MS), a urinary metabolomics method was used to study the mechanism of exercise intervention on diabetes mellitus. Based on the principal component analysis (PCA), it was found that the DM group and control group were separated into two different clusters. The DME group was located between the DM group and the control group, closer to the control group. Twelve significantly changed metabolites of diabetes mellitus were detected and identified, including glycolate, 4-methyl phenol, benzoic acid, 1H-indole, arabinitol, threitol, ribonic acid, malic acid, 2,3-dihydroxy-butanoic, aminomalonic acid, l-ascorbic acid and 3-hydroxy hexanedioic acid. After exercise, seven metabolites were significantly changed, compared with the control group, the relative contents of benzoic acid, aminomalonic acid, tetrabutyl alcohol and ribonucleic acid in the diabetic exercise group decreased significantly. The relative contents of 2,3-dihydroxybutyric acid, l-ascorbic acid and 3-hydroxy adipic acid increased significantly. l-ascorbic acid and aminomalonic acid which related with the oxidative stress were significantly regulated to normal. The results showed that exercise could display anti-hyperglycemic and anti-hyperlipidemic effects. The exercise had antioxidation function in preventing the occurrence of complications with diabetes mellitus to some extent. The work illustrates that the metabolomics method is a useful tool to study the mechanism of exercise treatment.

Open access

Fiona Broughton Pipkin, Hiten D Mistry, Chandrima Roy, Bernhard Dick, Jason Waugh, Rebecca Chikhi, Lesia O Kurlak and Markus G Mohaupt

have used immunoassays which have the problem of steroid cross reactivity (20, 21) . We have addressed this problem by utilising gas chromatography-mass spectrometry (GC-MS) (22) . In addition, we have measured steroids in 24 h urine collections

Open access

Aneta Gawlik, Michael Shmoish, Michaela F Hartmann, Stefan A Wudy, Zbigniew Olczak, Katarzyna Gruszczynska and Ze’ev Hochberg

ultrasonography – L1 L , or both – L1 AL ) where defined as liver disease – L1 as compared to L0 – without markers of liver disease. Gas chromatography-mass spectrometry (GC-MS) of urinary steroids Steroid metabolites in 24-h urine samples were analyzed by

Open access

L Ghataore, I Chakraborti, S J Aylwin, K-M Schulte, D Dworakowska, P Coskeran and N F Taylor

conjugates were hydrolysed enzymatically using Helix pomatia digestive juice. The free steroid products were then re-extracted and methyl oxime–trimethylsilyl ether (MO–TMS) derivatives were prepared before analysis by gas chromatography–mass spectrometry

Open access

I Savchuk, M L Morvan, J P Antignac, K Gemzell-Danielsson, B Le Bizec, O Söder and K Svechnikov

The onset of steroidogenesis in human fetal adrenal glands (HFA) during the first trimester is poorly investigated. An unresolved question is the capacity of the HFA to produce potent androgen DHT via conventional and/or the backdoor pathway(s) at the end of first trimester, when androgen-responsive organs are developed. Our aim was to explore steroidogenesis and the expression of steroidogenic enzymes and transcription factors in HFA at gestational weeks (GW) 9–12 with focus on their androgenic potential. Steroids in the HFA were analyzed by gas chromatography/mass spectrometry. The expression of steroidogenic enzymes and transcription factors in the HFA at GW9–12 was investigated by qPCR, automated Western blotting and immunohistochemistry. We demonstrated that during GW9–12 HFA produced steroids of the ∆5, ∆4 and the backdoor pathways of the biosynthesis of DHT, though the latter was limited to production of 17α-OH-dihydroprogesterone, androsterone and androstanedione without further conversion to DHT. The only androgens identified in the HFA were testosterone and androsterone, a precursor in the biosynthesis of DHT. We also observed higher levels of CYP17A1 but low expression of 3βHSD2 at GW11–12 in the HFA. Elevated levels of CYP17A1 were associated with an increased expression of SF-1 and GATA-6. Altogether, our data demonstrate that of those steroids analyzed, the only potent androgen directly produced by the HFA at GW9–12 was testosterone. The onset of steroidogenesis in the HFA is a complex process that is regulated by the coordinated action of related transcription factors.

Open access

C L Bodinham, L Smith, E L Thomas, J D Bell, J R Swann, A Costabile, D Russell-Jones, A M Umpleby and M D Robertson

enzymatically for glucose concentration using a Cobas Mira (Roche Laboratories). Isotopic enrichment of the same plasma samples was measured by gas chromatography–mass spectrometry on an HP5971A mass selective detector (Agilent, Santa Clara, CA, USA). The

Open access

Sandra R Dahl, Ingrid Nermoen, Ingeborg Brønstad, Eystein S Husebye, Kristian Løvås and Per M Thorsby

Mathian B Millot F Patricot MC Mathieu E Queyrel N Lacroix I Somma-Delpero C Boudou P. Testosterone measured by 10 immunoassays and by isotope-dilution gas chromatography-mass spectrometry in sera from 116 men, women, and children . Clinical Chemistry

Open access

Marloes L P Langelaan, Jérôme M H Kisters, Mirjam M Oosterwerff and Arjen-Kars Boer

-specific serum cortisol responses to the adrenocorticotrophin test: comparison of gas chromatography-mass spectrometry and five automated immunoassays . Clinical Endocrinology 2013 78 673 – 680 . ( ) 22994849 10.1111/cen

Open access

Federica Saponaro, Alessandro Saba, Sabina Frascarelli, Concetta Prontera, Aldo Clerico, Marco Scalese, Maria Rita Sessa, Filomena Cetani, Simona Borsari, Elena Pardi, Antonella Marvelli, Claudio Marcocci, Claudio Passino and Riccardo Zucchi

-linked immunoassays (ELISAs), radioimmunoassay (RIAs), chemiluminescence assays, high-performance liquid chromatography with UV detection (HPLC-UV), gas chromatography mass spectrometry and more recently liquid chromatography mass spectrometry (LC-MS-MS) ( 28

Open access

M P Schuijt, C G J Sweep, R van der Steen, A J Olthaar, N M M L Stikkelbroeck, H A Ross and A E van Herwaarden

reference measurement procedure for serum free testosterone based on ultrafiltration and isotope dilution-gas chromatography-mass spectrometry . Clinical Chemistry 2004 50 2101 – 2110 . ( ) 10.1373/clinchem