Page 141 - Malaysian Journal of Health Promotion, Vol 4 (Supplementary 1) 2022

Malaysian Journal of Health Promotion, Vol 4 (Supplementary 1) 2022
14 MOH-AMM Scientific Meeting 2022 in conjunction with 23 NIH Scientific Conference Abstract Book
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RESULTS: Our findings showed significantly reduced of ARSA activity from the baseline
median of 160.29 nmol/ml/hour at concentration 200 µg/mL of lactose (p=0.004). We also
found there was 50% of inhibition of enzyme activity at lactose concentration of 738 µg/mL.
DISCUSSION/CONCLUSION: Lactose was found to significantly interfere with ARSA assay's
activity. Therefore, patients who are suspected with MLD should avoid taking any lactose-
containing products before sampling to avoid false positive results.

ID 185 EFFECT OF ASCORBIC ACID ON ARYLSULPHATASE A ACTIVITIES IN HUMAN PLASMA

1
1
1
Balqis Kamarudin , Affandi Omar , Salina Abdul Rahman , Fatimah Diana Amin Nordin , Nur JannaimMohamad ,
1
1
2
1
Fatin Nurin Najma Latif , Julaina Abdul Jalil
1 Inborn Errors of Metabolism & Genetic Unit, Nutrition, Metabolism & Cardiovascular Research Centre (NMCRC),
Institute for Medical Research, National Institutes of Health Complex, Ministry of Health
2 Faculty of Science and Marine Environment, Universiti Malaysia Terengganu

INTRODUCTION: Arylsulfatase A (ARSA) is a lysosomal enzyme involved in the breakdown of
sulphated macromolecules. Deficiency of the enzyme causes metachromatic leukodystrophy
(MLD). Ascorbic acid (AA) is a water-soluble antioxidant and also as a co-factor for many
enzymes. However, high doses of AA may reverse the role from antioxidant to pro-oxidant.
Therefore, in this study we try to investigate the effect of AA on the ARSA activities in human
plasma.
METHODS: Various concentrations of AA were spiked into six independent plasma samples.
The assay of ARSA was carried out and the product was measured using microplate reader at
wavelength 515 nm. Descriptive analysis was completed using IBM SPSS version 22. Kruskal-
Wallis test was performed to compare any difference between group while Mann-Whitney
test was performed to compare for two groups.
RESULTS: The median and min-max value of ARSA activities in control group was 160.29
nmol/ml/hr (141.82; 216.91). Spiked sample demonstrated significant decreased in ARSA
activities (p<0.05) when compared to normal control. Inhibition profile showed ARSA
activities were reduced significantly starting from 2.2 mM - 8.5 mM of AA (p=0.01). The
concentration of producing 50% inhibition of ARSA activities was calculated at 8.4 mM.
DISCUSSION/CONCLUSION: In conclusion, addition of AA in the plasma samples resulted in a
decrease of the ARSA activities when compared with control. Further stability study should
be conducted so that adding AA to the sample can mimic positive control for MLD in
diagnostic testing. Besides that, interpretation of ARSA activities in patient taking AA as
supplement need to be done with caution.

ID 186 RETROSPECTIVE STUDY ON A1AT QUANTITATION AND PHENOTYPING IN THE
DIAGNOSIS OF ALPHA-1-ANTITRYPSIN DEFICIENCY

Hema A/P Arunagiri, Nurul Farahana Rosli, Nor Izzati Azami, Cefefe Stefenny Jolin, Bavani A/P Subramaniam,
Farah Azreen Mohammad, Is’adah Khisma Ismail, Siti Nurwani Ahmad Ridzuan, Nurul Izzati Hamzan, Noor
Hafizah Hassan
Unit Protein Khas, Specialized Diagnostic Center, Institute for Medical Research, National Institutes of Health,
Ministry of Health Malaysia

INTRODUCTION: Laboratory evaluation of Alpha-1-Antitrypsin (A1AT) deficiency involves
measurement of circulating AAT protein (quantitation) and characterization of A1AT genetic

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