Exfoliated buccal mucosa cells as a source of DNA to study oxidative stress.

The extent of oxidative DNA damage is considered a biomarker of carcinogenic process and could be investigated in population studies using easily obtained cells. The oxidized DNA base adduct 8-hydroxy-2-deoxyguanosine (8-OHdG) released by enzymatic hydrolysis of DNA is commonly assayed by high performance liquid chromatography with electrochemical detection. It is expressed as a ratio of 8-OHdG to unoxidized deoxyguanosine. We modified and improved this method, determined the optimal time for harvesting buccal mucosa cells (BMC), assessed whether they mirror peripheral circulating blood cell DNA damage, and compared the anticoagulants, heparin, and EDTA for consistency in measurement of leukocyte 8-OHdG. Thirty-one healthy participants, randomized into two groups, donated BMC and blood samples. Samples were collected at baseline and either 3 or 7 days after baseline. Results showed no correlation between 8-OHdG/deoxyguanosine ratios in BMC and peripheral blood leukocytes at any time point regardless of harvest time. BMC had much higher oxidative DNA damage, but displayed a 25.6% reduction in the oxidized DNA adduct level (P < 0.04) at 3 days after baseline. Leukocytes collected in heparin and EDTA had similar 8OHdG/deoxyguanosine ratios; however, EDTA was preferred, as it produced a clean nuclear pellet without hemoglobin contamination, and the results were less variable. This improved assay shows within subject stability over time in both leukocyte and BMC DNA damage, increasing the probability that small intervention differences can be detected in healthy subjects. Buccal cells provide an accessible pool of epithelial cells that represents higher levels of DNA damage than circulating leukocytes.     

Suppressive effects of Moringa oleifera Lam pod against mouse colon carcinogenesis induced by azoxymethane and dextran sodium sulfate

Moringa oleifera Lam (horseradish tree; tender pod or fruits) is a major ingredient in Thai cuisine and has some medicinal properties. Previous studies have shown potentially antioxidant, antitumor promoter, anticlastogen and anticarcinogen activities both in vitro and in vivo. The present study was conducted to investigate chemopreventive effects on azoxymethane (AOM)-initiated and dextran sodium sulfate (DSS)-promoted colon carcinogenesis in mice. Male ICR mice were divided into 8 groups: Group 1 served as a negative control; Group 2 received AOM/DSS as a positive control; Groups 3-5 were fed boiled freeze-dried M. oleifera (bMO) at 1.5%, 3.0% and 6.0%, respectively supplemented in basal diets for 5 weeks; Groups 6-8 were fed with bMO diets at the designed doses above for 2 weeks prior to AOM, during and 1 week after DSS administration. At the end of the study, colon samples were processed for histopathological examination. PCNA indices, and iNOS and COX-2 expression were assessed by immunohistochemistry. The results demonstrated the incidences and multiplicities of tumors in Groups 6-8 to be decreased when compared to Group 2 in a dose dependent manner, but this was significant only in Group 8. The PCNA index was also significantly decreased in Group 8 whereas iNOS and COX-2 protein expression were significantly decreased in Groups 7 and 8. The findings suggest that M. oleifera Lam pod exerts suppressive effects in a colitis-related colon carcinogenesis model induced by AOM/DSS and could serve as a chemopreventive agent.     

Multi-criteria Mapping of Stakeholders’ Viewpoints in Five Southeast Asian Countries on Strategies to Reduce Micronutrient Deficiencies Among Children and Women of Reproductive Age: Findings from the SMILING Project

Background

Despite scientific evidence on the potential impact or importance of specific interventions to improve micronutrient status of vulnerable groups, political commitment and extensive support from national stakeholders is paramount to support introduction and implementation of these interventions at national level. In order to develop efficient nutritional strategies to improve the micronutrient status of children < 5 years of age and women of reproductive age that will be supported by a wide range of stakeholders, a better understanding of viewpoints on the nutrition politics and strategies is necessary. Multi-criteria mapping (MCM) was successfully used to assess the stakeholder’s viewpoint in a wide variety of contexts since the late 1990s.

Objective

The objective of the present study was to assess the viewpoints of stakeholders on a wide range of potential nutritional interventions in the five Southeast Asian countries participating in the SMILING project.

Method

MCM methodology was used to appraise the stakeholder’s viewpoints in five countries.

Results

The results show that the overall stakeholders’ preference was for actions already implemented in their country rather than for new, innovative options, even for supplementation. Indirect interventions such like food fortification (except in Indonesia), delayed cord clamping or food-based approaches were generally less favored by the stakeholders. However, the majority of stakeholders agreed that new approaches should be considered and put in place in the future provided that evidence of their impact was demonstrated, that they received adequate technical support for their implementation and their monitoring, and that they will be accompanied by strong advocacy among decision-makers, civil society and beneficiaries.

Conclusions for practice

To conclude, for the introduction of new, innovative strategies to reduce micronutrient deficiencies in South-East Asia, convincing stakeholders appears to be the first hurdle to be taken.