Theses (MSc. Medical and Health Sciences)

In Malaysia, the rising incidence of type 2 diabetes mellitus (T2DM) among adolescent and adults is linked to obesity. Pharmaceutical therapy has been brought in to curb T2DM, more famously in the form of biguanides (metformin) and sulfonylureas (gliclazide). However, variation in the individual glycaemic response to metformin treatment might be due to heritability factors. Importantly, metformin has been reported to alter the microRNA (miRNA) expression profiles. Thus, the present study aims to provide data on differential expression of salivary miRNAs in responders and non-responders among T2DM patients under combined treatment of metformin and gliclazide. A total of 50 subjects were recruited each for responder and non-responder groups at the endocrine clinic of the Hospital Canselor Tuanku Mukhriz Universiti Kebangsaan Malaysia (HCTM). Subjects with HbA1c reduction levels of 0.5% or more were categorised as responders. The patients' demographic data including age, gender, BMI, WHR, ethnicity, smoking status, exercise routine and medical history were recorded. Total RNAs were isolated from the saliva collected and pooled prior to reverse-transcription-quantitative polymerase chain reaction (RT-qPCR) analysis. The levels of microRNA namely, miR 28-3p, miR 135a-5p, miR 126-5p, and miR 320a3p were determined using RNU6P as the endogenous control. Pearson's corelation coefficient analysis demonstrated significant (p<0.05) positive correlation between BMI (29.2 ± 1.25 kg/m2) and HbA1c reduction levels (0.78 ± 0.36%) and between WHR (0.91 ± 1.35) and HbA1c reduction, while age and HbA1c reduction had a negative correlation r = -0.126 with p-value = 0.008. Meanwhile Pearson's chi-square test demonstrated only smoking status (p<0.001) had a significant correlation with the HbA1c reduction levels. Based on the miRNA PCR assays, miR 135a-5p, miR 1265p, and miR 320a-3p were upregulated while miR 28-3p was downregulated in responders compared to non-responder regardless on ethnicity and smoking status. Among the Malay subjects, miR-126-5p was downregulated in the responders among smokers but upregulated in the responders among the non-smokers when compared to their counterparts of non-responder groups. Interestingly, smoking status was also found to be significantly correlated with the HbA1c reduction levels. The deregulation and upregulation of these four targeted miRNAs have been recognized as a contributing factor in several pathways across T2DM spectrum, encompassing insulin resistance, adherens junction, hippo signalling, and AMPK signalling, proposing these four targeted miRNAs to be potential biomarkers of T2DM while miR-126-5p downregulation within VEGF pathway should be researched further and within various ethnic groups as an indicator for both T2DM with smoking-related diseases.

Background: Adequate calcium intake is essential to maximize peak bone mass during the pre-pubertal stage, consecutively supporting bone growth and development as well as preventing bone disorders at Older ages. However, most Malaysian children do not meet calcium requirements from their habitual diets, thus delving into alternative methods for resolving challenges of low calcium intake is crucial. Supplementation with soluble corn fibre (SCF) has been shown to enhance calcium absorption which further improves bone health. The exact mechanism of the action is unclear, which might be due to the production of short-chain fatty acids (SCFAs). As SCFAs are mainly produced from indigestible carbohydrate fermentation by gut microbiome, dietary intake patterns may also play a role in determining SCFA levels and consequently affect bone status. Thus, this secondary data analysis aimed to investigate the association between serum SCFAs level with dietary intake patterns and bone health in Malaysian pre-adolescent children as well as the effect of soluble corn fibre on serum SCFAs level. Methods: A secondary data analysis from the PREBONE-Kids study, with 243 children aged 9-11 were included. Bone mineral density (BMD) and bone mineral content (BMC) were measured using dual-energy X-ray absorptiometry (DXA). Dietary intake was assessed using a 7-days diet history and food intake was further categorised into 23 food groups based on nutrient composition and preparation methods. Dietary intake patterns were then determined based on Malaysian Healthy Eating Index (M-HEI), which consists Of I l components, and Mediterranean Diet Quality Index for Children and Adolescents (KIDMED) questionnaire that comprised Of 16 components. Serum SCFAs were firstly extracted with methanol solvent, followed by measurement of SCFAs using gas chromatography coupled to a (flame-ionization detection detector. Serum SCFA levels were then quantified based on calibration standards. Results: Serum total SCFAs level was inversely correlated with TB BMI) (r (1 1 7) -0.183, p = 0.047). Specific food groups had a significant correlation with serum SCFAs level such as sweetened condensed milk (r (117) = -O. 184, p = 0.046), Sugafr sweetened beverages (r (1 17) = 0.183, p = 0.047), and whole grain (r (1 1 7) = -0.209, p = 0.022). However, dietary intake pattern was not associated with serum SCFAS level (p > 0.05). Significant differences in BMI) and BMC were found among dietary intake pattern groups based on either the M-HEI or KIDMED questionnaire, in which the group with healthier dietary intake patterns had higher bone parameters. Also, KIDMED score had been found to predict BMD (Total body (TB) BMD: = 0.146, p < 0.001; Total body less head (TBLH) BMI): - 0.081,p - 0.008), and BMC (TB BMC: = 0.507, p < 0.001; TBLH BMC: ß = 0.059, p < 0.001) among the study population. There were no significant effect Of SCF on acetic acid (p I .000), propionic acid (p = 1.000), and butyric acid (p = 1.000) over time. Conclusion: The study found that a healthier dietary intake pattern was associated with better BMD and BMC. In addition, although serum SCFAs were associated with specific foods, serum SCFAs were not associated with any specific dietary intake pattern. Also, BMD and BMC were associated with KIDMED score. The supplementation of soluble corn fibre (SCF) did not impact the concentration of serum SCFAs, which amrmed the result Of the PREBONE-Kids study that no added benefit Of SCF supplementation on bone mass. Further research is essential to support the findings as well as to comprehend the mechanism of SCF in the study population. Keywords: Bone health, dietary pattern, pre-adolescent children, short-chain fatty acids, soluble corn fibre

Introduction: The current efforts to reduce the prevalence of anaemia have been widely practised among the primary healthcare facilities in Malaysia, such as prenatal haematinics and nutrition education. Although there have been several studies on anaemic status generally among pregnant mothers, none have been conducted specifically among urban B40 pregnant mothers in Malaysia. Objective: This study aims to determine the effect of antenatal haematinics on maternal haemoglobin and the association between maternal haemoglobin, HbA1c level, dietary intake, and total gestational weight gain among B40 pregnant mothers. Method: This was a prospective cohort study in which eligible pregnant mothers belonging to the B40 strata were recruited from a health clinic in Kuala Lumpur, Malaysia. Sociodemographic information was collected from all the participants. Pregnant mothers were followed up with at least 3 prenatal visits, including baseline, first follow-up (16-19 weeks), second follow-up (24-26 weeks) and third follow-up (34-36 weeks). Routine assessments of haemoglobin, HbA1c, anthropometry, blood pressure, 24-hour dietary recall and compliance to haematinics were obtained for each follow-up. Data analysis was performed using Statistical Packages for Social Science (SPSS) version 28. Result: A total of sixty-two pregnant mothers were recruited. Most of them (>80%) had normal HbA1c level during pregnancy. After haematinics were provided, the maternal mean haemoglobin significantly decreased by 1 g/dL from baseline to third follow-up (p<0.001); and a significant increased by 0.6 g/dL was observed from second follow-up to third follow-up (p<0.001). Despite the significant decreased in haemoglobin across the follow-up visits, the mean haemoglobin at each follow-up was considered normal. Less than one-third of the B40 pregnant mothers had anaemia at 36 weeks of pregnancy. Majority (87.1%) delivered normal weight babies. Most of them (>60%) did not get adequate energy, carbohydrates, and micronutrients (iron, folate, vitamin B12, zinc and vitamin C) from their daily diet however the majority (>90%) had adequate protein intake and high-fat diets. Most of them (48.4%) had normal pre-pregnancy body mass index. Those with a normal pre-pregnancy body mass index had the highest proportion (56.7%) of inadequate weight gain. Total gestational weight gain was found to be positively correlated with energy, protein, and fat intake (energy intake, r=0.289, p<0.05; protein intake, r=0.352, p<0.01; fat intake, r=0.251, p<0.05). Maternal age had a positive linear relationship with birth weight 0.3g (95%CI: 0.004, 0.051g)., p=0.021. Household income less than RM3970 had a negative relationship with birth weight 0.3g (95%CI: -0.551, -0.021g)., p=0.035. Maternal haemoglobin level had a negative linear relationship with birth weight -0.2 g (95%CI: -0.370, -0.017g), (p=0.029). Maternal dietary iron intake had a positive linear relationship with birth weight 0.5 g (95%CI: 0.006, 0.105g), (p=0.020). Conclusion: The provision of haematinics during pregnancy is beneficial in optimising or maintaining a healthy level of haemoglobin among the studied B40 pregnant mothers. Higher intake of energy, protein and fat was positively correlated with total gestational weight gain. The study also found that maternal age, monthly household income, maternal haemoglobin and dietary iron intake were the significant predictors of birth weight. Increased maternal age and dietary iron intake increased the birth weight. Increased mean haemoglobin level throughout the pregnancy and income level less than RM3,970 decreased the birth weight. The babies born in this cohort must be followed up until their second year of life to study their growth pattern.

Workload-related mental fatigue can have detrimental impact on both work performance and mental health. Saccadic eye movement characteristics (SEMC) have been used to detect mental fatigue however the changes in SEMCs have not been associated to other mental fatigue related measures. This study aims to identify the changes in SEMCs and their associations with mental fatigue-related psychological measures. Participants were required to go through three saccade tasks (pro, anti and mixed) that had elevating difficulty levels. The SEMCs, mental load, and sleepiness were recorded after at each task whilst saliva cortisol levels, fatigue and energy scores were measured pre and post experiment. Data from a total of 55 individuals (aged between 18 to 37 years old) were analysed. Results showed that participants had the highest accuracy rates in the prosaccade task, followed by the mixed task and lastly the antisaccade task. The Visual Analogue Scale-Fatigue (VAS-F) scores showed that there was a slight increase in fatigue and energy in the post-experiment, however, the difference was not statistically significant. However, the participants experienced an increase in mental loading as they progressed from the prosaccade, antisaccade, and to mixed task. From pre and post experiment, the SEMCs were seen to change in the following ways: saccade latency decreased, pupil dilation increased, and peak velocity dropped. In conclusion, the task was able to increase mental loading in participants but may not have been able to significantly induce mental fatigue as suggested by the VAS-F scores. The associations between the psychological measures and SEMCs observed across the three tasks are discussed. The findings of this study can provide a better understanding of the association of saccadic eye movement characteristics with mental fatigue psychological measures, potentially providing insights into new methods for detecting and assessing mental fatigue objectively. Keywords: eye tracking, digital health, saccades, mental load, inhibition, attention

Breast cancer is the leading cause of death among women in Malaysia and worldwide. The overall percentage of breast cancer patients in Malaysia is 31% compared to other types of cancer. In Malaysia, the number of new cases of female breast cancer in 2020 was reported to be 11.7%. Recently, treatment for breast cancer has changed to a new perspective and researchers are finding evidence to prove that natural bioactive compounds can also exhibit anti-cancer activity with increased health benefits and reduced or no side effects compared to other chemoprevention drugs. One such compound known for its anti-cancer potential is tocotrienol, a member of the vitamin E family. Among the isomers of tocotrienols, gamma-tocotrienol (γ-T3) is known to mediate the intracellular signalling of cancer cells via various mechanisms such as promoting apoptosis, anti-angiogenesis, antimetastatic and other important cellular mechanisms. In this study, the triple negative MDA-MB-468 human breast cancer cells were treated with γ-T3 at its IC50 concentration established at 72 hours and the total RNA was isolated using RNeasy Mini columns (Qiagen, Valencia, CA, USA). Samples that yielded 7.4 to 8.4 for RNA integrity number, exhibited a clear gel image and for which no DNA contamination was observed on the gel were used for microarray gene expression profiling. Transcriptome Analysis Console (TAC) with expression console were further used for the identification of differential expression genes and generation of interactive data visualisations. DAVID database analysis was used to perform enrichment analysis for the differentially expressed genes in response to γ-T3. Differentially regulated genes identified through STRING and KEGG analysis showed the involvement of γ-T3 in regulating the cell cycle pathways. The MDA-MB-468 human breast cancer cells were found to have a significant response to γ-Breast cancer is the leading cause of death among women in Malaysia and worldwide. The overall percentage of breast cancer patients in Malaysia is 31% compared to other types of cancer. In Malaysia, the number of new cases of female breast cancer in 2020 was reported to be 11.7%. Recently, treatment for breast cancer has changed to a new perspective and researchers are finding evidence to prove that natural bioactive compounds can also exhibit anti-cancer activity with increased health benefits and reduced or no side effects compared to other chemoprevention drugs. One such compound known for its anti-cancer potential is tocotrienol, a member of the vitamin E family. Among the isomers of tocotrienols, gamma-tocotrienol (γ-T3) is known to mediate the intracellular signalling of cancer cells via various mechanisms such as promoting apoptosis, anti-angiogenesis, antimetastatic and other important cellular mechanisms. In this study, the triple negative MDA-MB-468 human breast cancer cells were treated with γ-T3 at its IC50 concentration established at 72 hours and the total RNA was isolated using RNeasy Mini columns (Qiagen, Valencia, CA, USA). Samples that yielded 7.4 to 8.4 for RNA integrity number, exhibited a clear gel image and for which no DNA contamination was observed on the gel were used for microarray gene expression profiling. Transcriptome Analysis Console (TAC) with expression console were further used for the identification of differential expression genes and generation of interactive data visualisations. DAVID database analysis was used to perform enrichment analysis for the differentially expressed genes in response to γ-T3. Differentially regulated genes identified through STRING and KEGG analysis showed the involvement of γ-T3 in regulating the cell cycle pathways. The MDA-MB-468 human breast cancer cells were found to have a significant response to γ-Breast cancer is the leading cause of death among women in Malaysia and worldwide. The overall percentage of breast cancer patients in Malaysia is 31% compared to other types of cancer. In Malaysia, the number of new cases of female breast cancer in 2020 was reported to be 11.7%. Recently, treatment for breast cancer has changed to a new perspective and researchers are finding evidence to prove that natural bioactive compounds can also exhibit anti-cancer activity with increased health benefits and reduced or no side effects compared to other chemoprevention drugs. One such compound known for its anti-cancer potential is tocotrienol, a member of the vitamin E family. Among the isomers of tocotrienols, gamma-tocotrienol (γ-T3) is known to mediate the intracellular signalling of cancer cells via various mechanisms such as promoting apoptosis, anti-angiogenesis, antimetastatic and other important cellular mechanisms. In this study, the triple negative MDA-MB-468 human breast cancer cells were treated with γ-T3 at its IC50 concentration established at 72 hours and the total RNA was isolated using RNeasy Mini columns (Qiagen, Valencia, CA, USA). Samples that yielded 7.4 to 8.4 for RNA integrity number, exhibited a clear gel image and for which no DNA contamination was observed on the gel were used for microarray gene expression profiling. Transcriptome Analysis Console (TAC) with expression console were further used for the identification of differential expression genes and generation of interactive data visualisations. DAVID database analysis was used to perform enrichment analysis for the differentially expressed genes in response to γ-T3. Differentially regulated genes identified through STRING and KEGG analysis showed the involvement of γ-T3 in regulating the cell cycle pathways. The MDA-MB-468 human breast cancer cells were found to have a significant response to γ-T3 treatment as the observation under phase contrast microscopy showed inhibition of cell proliferation. A total of 1091 genes were identified in MDA-MB-468 cells, of which 84 genes were found to be associated with breast cancer. Out of these 84 genes, 50% of it were downregulated after the treatment with γ-T3. From these subsets of genes, a total of 10 genes such as PLK1, CDKN1A, CDK1, PTTG1, MAD2L1, SKP2, CDC20, TTK, MYC, and ATM were identified to be involved in cell proliferation inhibition and cell cycle arrest. Furthermore, some of the histone mediated genes such as HIST1H2BI, HIST1H2BO, and HIST1H3F were also found to be downregulated with γ-T3 treatment which further strongly indicate inhibition of breast cancer cell proliferation. Overall, the results from this study suggest γ-T3 s' ability to modulate the anti-cancer mechanisms in MDA-MB-468 human breast cancer cells and have therapeutic potential.