MBC 141 Medical Biochemistry : Gestational Diabetes Mellitus

Answer:

Summary of the article “GC–MS based Gestational Diabetes Mellitus longitudinal study: Identification of 2-and 3-hydroxybutyrate as potential prognostic biomarkers”.

Material and methods:

• 68 participants were considered for this study grouped with the same age (22 – 37 years) and gestation period (22 – 28 weeks). Amongst them, 24 cases and 24 control study were included in the study.
• All the parameters were standardized using standard mix.
• Analysis of GC- Q/MS was used for the fingerprinting of plasma metabolomics. GC-MS data, detection of peak, and spectra were analyzed using MSD ChemStation Software.
• Multivariate statistical analysis was used to assess the variance and unbiased of the data.

Results:

• Plasma fingertips were allowed for the women from control pregnant with GDM both in the 2^ndand 3^rd trimesters of gestation period.
• In the second trimester of gestation period, there was no difference in acquired data between the control and test subjects.
• Three months after post- partum, 7 women with GDM had altered glycemia.
• At three month post- partum, clear separation for glycemic alterations were observed for GDM women when multivariate PLS-DA model were used.
• Metabolic profiles were more or less same after delivery. Four women out of them developed Type 2 Diabetes Mellitus (DM) within 2 years postpartum.

Discussions:

• 3-hydroxybutyrate, stearic acid, and 2-hydroxybutyrate have the strongest discrimination effect for the women in 2^ndtrimester of gestation.
• Gestational Diabetes Mellitus consists of metabotypes which are risk factors for future complication. GDM and T2Dm have many common risk factors.
• Metabolites can be used to predict the both prediabetes and T2DM
• 3-hydroxybutyrate and 2-hydroxybutyrate might be used as biomarkers for the prediction of diabetic complications at the time of prognosis for the women with gestational diabetes during post- partum stage.

Summary of the article “Optimization and validation of a chiral GC–MS method for thedetermination of free d-amino acids ratio in human urine: Applicationto a Gestational Diabetes Mellitus study”.

Materials and methods:

• 20 healthy pregnant Caucasian women and 20 Caucasian women with GDM were selected for this study. Screening for GDM were done at 22 to 28 weeks of gestation in a routinely manner.
• Participants were all between the age group of 22 -37 years.
• 1 ml of sample was collected during the first time urination and GC- MS was used to carry out the enantiomeric separation. All the parameters regarding this examination were optimized for the both standard and urine samples. For instance, temperature program, mass range and split ratio were optimized for GC- MS.
• Reliable and new chiral GC- MS method were used on a Chirasil-l-Val capillary column for efficient separation.

Results:

• Various amino acids such as d-Pro, d-Ala, d-Met, d-Ser were used to validate the system in terms of sensitivity, precision, accuracy and linearity. Amino acids identification (from urine sample) in this system was depended on the mass spectra and retention time.
• Percentage of _D-Relative amounts were measured using various amino acids like Phe, Val, Ala, Ser, Asx, Thr, and so on.
• Statistically significant results (p value <0.05) were observed for only _D-Phe.

Discussion:

• Percentage of d-amino acids (d-Orn, d-Ala, d-Ly, and d-Ser)were found higher in GDM group compared to control.
• This method can be used to determination of chiral amino acids for metabolic disorders like diabetes.
• _D-Phe might be responsible for the insulin resistance in early stage Gestational Diabetes Mellitus (GDM). Although, in the article it has been stated that this only a hypothesis and further research is needed to approve this theory.