Prerequisite Evaluation of Anaerobic Settings for Gut Microbiome Functional Studies

Colon cancer-associated gut bacteria were mostly identified via next-generation sequencing in gut microbiome profiling studies. Anaerobic culture systems can be used to culture colon cells with these gut bacteria to further confirm the tumorigenic properties of these bacteria. Nevertheless, it is unclear how colon cells will grow in an anaerobic environment, as most cells are cultured aerobically. Therefore, we investigated the survival and viability of HT-29, a colon cancer cell line in an anaerobic culture system, and compared it to the usual culture condition in an aerobic setup. Interestingly, we found that HT-29 was able to grow in the anaerobic setup. Its viability was similar for both culture conditions, with only a slower growth rate observed in the anaerobic setup. Furthermore, gene expression studies showed that the cells were not under severe anaerobic stress even when exposed to the oxygen-deprived environment.This study provided results on some baseline parameters of an anaerobic colon cell culture system, and will be useful for journal readers who wish to investigate functional properties of anaerobic bacteria

Highly sensitive and reliable human sex determination using multiplex PCR

Gender validation is indispensable in data verification for demographic information particularly in large-scale population studies and also as part of the quality assurance of biospecimen repositories. Gender validation is also critical as part of quality control processes before specimens are subjected to sequencing analysis to identify germline and somatic mutations. The SRY gene is considered a useful signature gene marker that differentiates male from female. The aim of the study was to validate the SRY gene marker for use in gender determination in large cohort studies. SRY gene-specific sequences were amplified by PCRCR, electrophoresed on agarose gels and the 254 bp band was visualized for male samples. A series of DN A template concentrations were tested for sensitivity determination. The reaction was validated on 48 gender-blinded samples obtained from the UMBI BioBank to determine the specificity. ATL1 gene-specific sequence on X chromosome was used as the internal control. This PCR method has demonstrated 100% gender specificity. The sensitivity of the reaction was demonstrated with as low as 0.1 ng male DN A. The findings had suggested that SRY analysis by Multiplex PCR is a highly sensitive and specific method for gender determination and can be extremely useful for large-scale samples

Validation of Self-Reported Smoker and Second Hand Smoke Exposure by Urinary Cotinine within The Malaysian Cohort Project

Background: Validation of self-reported questionnaire is very crucial in ensuring the quality and reliability of data collection. Objective: The aim of this study were i) to validate the questionnaire on tobacco smoke intake and second hand smoke exposure among The Malaysian Cohort (TMC) subjects through the determination of urinary cotinine levels, ii) to determine the optimal cut-off point of urine cotinine that discriminates smokers from non-smokers and iii) to estimate misclassification rate between self-reported smoking and urinary cotinine level.Methods: Urine samples from a total of 775 The Malaysian Cohort subjects (104 smokers, 102 former smokers and 569 non-smokers) were obtained and urinary cotinine levels were determined by high-performance liquid chromatography (HPLC). Differences between groups were compared using Kruskal Wallis and Mann-Whitney tests. The Receiver Operating Characteristic (ROC) curved was performed to define the optimal urinary cotinine cut-off point.Results: Urinary cotinine concentration significantly (p<0.001) correlated with smoking status (r=0.46), the average number of cigarettes smoked per day (r=0.53), duration of smoking (r=0.33) and number of cigarettes packed per year (r=0.47). Smokers and second hand smokers have significantly higher median cotinine levels (978.40 and 21.31 respectively) compared to non-smokers (15.52) and non-exposed (13.60) subjects. Cotinine level at cut-off value of 1.51 ng/mg creatinine is able to distinguish smokers and non-smokers with a sensitivity of 84.62% and specificity of 81.97%.Conclusion: The Malaysian Cohort self-reported smoking questionnaire is a reliable tool in assessing the use of tobacco and second hand smoke exposure among the subjects

Body composition and risk factors for cardiovascular disease in global multi-ethnic populations

Background: No large-scale studies have compared associations between body composition and cardiovascular risk factors across multi-ethnic populations. Methods: Population-based surveys included 30,721 Malay, 10,865 Indian and 25,296 Chinese adults from The Malaysian Cohort, and 413,737 White adults from UK Biobank. Sex-specific linear regression models estimated associations of anthropometry and body composition (body mass index [BMI], waist circumference [WC], fat mass, appendicular lean mass) with systolic blood pressure (SBP), low-density lipoprotein cholesterol (LDL-C), triglycerides and HbA1c. Results: Compared to Malay and Indian participants, Chinese adults had lower BMI and fat mass while White participants were taller with more appendicular lean mass. For BMI and fat mass, positive associations with SBP and HbA1c were strongest among the Chinese and Malay and weaker in White participants. Associations with triglycerides were considerably weaker in those of Indian ethnicity (eg 0.09 [0.02] mmol/L per 5 kg/m2 BMI in men, vs 0.38 [0.02] in Chinese). For appendicular lean mass, there were weak associations among men; but stronger positive associations with SBP, triglycerides, and HbA1c, and inverse associations with LDL-C, among Malay and Indian women. Associations between WC and risk factors were generally strongest in Chinese and weakest in Indian ethnicities, although this pattern was reversed for HbA1c. Conclusion: There were distinct patterns of adiposity and body composition and cardiovascular risk factors across ethnic groups. We need to better understand the mechanisms relating body composition with cardiovascular risk to attenuate the increasing global burden of obesity-related disease

Tocotrienol rich fraction supplementation improved lipid profile and oxidative status in healthy older adults: A randomized controlled study

<p>Abstract</p> <p>Background</p> <p>Vitamin E supplements containing tocotrienols are now being recommended for optimum health but its effects are scarcely known. The objective was to determine the effects of Tocotrienol Rich Fraction (TRF) supplementation on lipid profile and oxidative status in healthy older individuals at a dose of 160 mg/day for 6 months.</p> <p>Methods</p> <p>Sixty-two subjects were recruited from two age groups: 35-49 years (n = 31) and above 50 years (n = 31), and randomly assigned to receive either TRF or placebo capsules for six months. Blood samples were obtained at 0, 3^rdand 6^thmonths.</p> <p>Results</p> <p>HDL-cholesterol in the TRF-supplemented group was elevated after 6 months (p < 0.01). Protein carbonyl contents were markedly decreased (p < 0.001), whereas AGE levels were lowered in the > 50 year-old group (p < 0.05). Plasma levels of total vitamin E particularly tocopherols were significantly increased in the TRF-supplemented group after 3 months (p < 0.01). Plasma total tocotrienols were only increased in the > 50 year-old group after receiving 6 months of TRF supplementation. Changes in enzyme activities were only observed in the > 50 year-old group. SOD activity was decreased after 3 (p < 0.05) and 6 (p < 0.05) months of TRF supplementation whereas CAT activity was decreased after 3 (p < 0.01) and 6 (p < 0.05) months in the placebo group. GPx activity was increased at 6 months for both treatment and placebo groups (p < 0.05).</p> <p>Conclusion</p> <p>The observed improvement of plasma cholesterol, AGE and antioxidant vitamin levels as well as the reduced protein damage may indicate a restoration of redox balance after TRF supplementation, particularly in individuals over 50 years of age.</p

Phthalates in children toys available in Malaysian market: quantification and potential human health risk

In Malaysia, inexpensive toys are sold in various urban and rural shops. Although safety regulations for toys are available in Malaysia there are limited reports about the chemicals in toys. Thus, this study aimed to assess the levels of phthalates (bis-[2-ethylhexyl] phthalate [DEHP], diethyl phthalate [DEP], diisobutyl phthalate [DiBP] and dibutyl phthalate [DBP]) in inexpensive toys sold at local markets in Kuala Lumpur (Malaysia) and its health risks to children. All 30 toys analysed exceeded the European Union limit (0.1 % by mass) indicating that the phthalate used as plasticizers is still prominent in toys. Bis-[2-ethylhexyl] phthalate (DEHP) was the highest detected phthalate in toy sample which was manufactured in Malaysia and sold without Malaysian Conformity Mark. Significant association was found between phthalate levels and country, indicating a need to monitor and raise public awareness about potential toxic chemicals in inexpensive toys and children’s products. There are few inexpensive toys that have a hazard index value of more than one, which is associated with developmental toxicity and causes developmental effects in children. Given the severity and complexity of these toys to children health, there is a need for regular monitoring and effective enforcements to develop an acceptable baseline level of children toys products manufactured in or imported to Malaysia. Furthermore, risk management efforts should also include all the stakeholders involved in toy production, policy makers as well as consumers to ensure only toy products with proper labels being sole and purchased

Metaproteomic analysis of human gut microbiota: where are we heading?

Abstract The human gut is home to complex microbial populations that change dynamically in response to various internal and external stimuli. The gut microbiota provides numerous functional benefits that are crucial for human health but in the setting of a disturbed equilibrium, the microbial community can cause deleterious outcomes such as diseases and cancers. Characterization of the functional activities of human gut microbiota is fundamental to understand their roles in human health and disease. Metaproteomics, which refers to the study of the entire protein collection of the microbial community in a given sample is an emerging area of research that provides informative details concerning functional aspects of the microbiota. In this mini review, we present a summary of the progress of metaproteomic analysis for studying the functional role of gut microbiota. This is followed by an overview of the experimental approaches focusing on fecal specimen for metaproteomics and is concluded by a discussion on the challenges and future directions of metaproteomic research

Identification of Schizosaccharomyces pombe in the guts of healthy individuals and patients with colorectal cancer: preliminary evidence from a gut microbiome secretome study

Abstract Over the years, genetic profiling of the gut microbiome of patients with colorectal cancer (CRC) using genome sequencing has suggested over-representation of several bacterial taxa. However, little is known about the protein or metabolite secretions from the microbiota that could lead to CRC pathology. Proteomic studies on the role of microbial secretome in CRC are relatively rare. Here, we report the identification of proteins from Schizosaccharomyces pombe found in the stool samples of both healthy individuals and patients with CRC. We found that distinctive sets of S. pombe proteins were present exclusively and in high intensities in each group. Our finding may trigger a new interest in the role of gut mycobiota in carcinogenesis

Pathogens and Carcinogenesis: A Review

Cancer is a global health problem associated with genetics and unhealthy lifestyles. Increasingly, pathogenic infections have also been identified as contributors to human cancer initiation and progression. Most pathogens (bacteria, viruses, fungi, and parasites) associated with human cancers are categorized as Group I human carcinogens by the International Agency for Research on Cancer, IARC. These pathogens cause carcinogenesis via three known mechanisms: persistent infection that cause inflammation and DNA damage, initiation of oncogene expression, and immunosuppression activity of the host. In this review, we discuss the carcinogenesis mechanism of ten pathogens, their implications, and some future considerations for better management of the disease. The pathogens and cancers described are Helicobacter pylori (gastric cancer), Epstein-Barr virus (gastric cancer and lymphoma), Hepatitis B and C viruses (liver cancer), Aspergillus spp. (liver cancer), Opisthorchis viverrine (bile duct cancer), Clonorchis sinensis (bile duct cancer), Fusobacterium nucleatum (colorectal cancer), Schistosoma haematobium (bladder cancer); Human Papillomavirus (cervical cancer), and Kaposi’s Sarcoma Herpes Virus (Kaposi’s sarcoma)