Twin metabolomics: the key to unlocking complex phenotypes in nutrition research

Perspective: Council for Responsible Nutrition Science in Session. Optimizing Health with Nutrition-Opportunities, Gaps, and the Future

Achieving optimal health is an aspirational goal for the population, yet the definition of health remains unclear. The role of nutrition in health has evolved beyond correcting malnutrition and specific deficiencies and has begun to focus more on achieving and maintaining 'optimal' health through nutrition. As such, the Council for Responsible Nutrition held its October 2022 Science in Session conference to advance this concept. Here, we summarize and discuss the findings of their Optimizing Health through Nutrition - Opportunities and Challenges workshop, including several gaps that need to be addressed to advance progress in the field. Defining and evaluating various indices of optimal health will require overcoming these key gaps. For example, there is a strong need to develop better biomarkers of nutrient status, including more accurate markers of food intake, as well as biomarkers of optimal health that account for maintaining resilience-the ability to recover from or respond to stressors without loss to physical and cognitive performance. In addition, there is a need to identify factors that drive individualized responses to nutrition, including genotype, metabotypes, and the gut microbiome, and to realize the opportunity of precision nutrition for optimal health. This review outlines hallmarks of resilience, provides current examples of nutritional factors to optimize cognitive and performance resilience, and gives an overview of various genetic, metabolic, and microbiome determinants of individualized responses.

India's Opportunities and Challenges in Establishing a Twin Registry: An Unexplored Human Resource for the World's Second-Most Populous Nation

Nature and nurture have always been a prerogative of evolutionary biologists. The environment's role in shaping an organism's phenotype has always intrigued us. Since the inception of humankind, twinning has existed with an unsettled parley on the contribution of nature (i.e. genetics) versus nurture (i.e. environment), which can influence the phenotypes. The study of twins measures the genetic contribution and that of the environmental influence for a particular trait, acting as a catalyst, fine-tuning the phenotypic trajectories. This is further evident because a number of human diseases show a spectrum of clinical manifestations with the same underlying molecular aberration. As of now, there is no definite way to conclude just from the genomic data the severity of a disease or even to predict who will get affected. This greatly justifies initiating a twin registry for a country as diverse and populated as India. There is an unmet need to set up a nationwide database to carefully curate the information on twins, serving as a valuable biorepository to study their overall susceptibility to disease. Establishing a twin registry is of paramount importance to harness the wealth of human information related to the biomedical, anthropological, cultural, social and economic significance.

The Association Between Fecal Short-Chain Fatty Acids, Gut Microbiota, and Visceral Fat in Monozygotic Twin Pairs

PURPOSE

To examine the association of short-chain fatty acids (SCFAs), gut microbiota and obesity in individual twins and to control for genetic and shared environmental effects by studying monozygotic intrapair differences.

PATIENTS AND METHODS

The study recruited 20 pairs of monozygotic twins. Body composition measurements were performed by using the multi-frequency bioelectrical impedance technique. SCFAs were extracted from feces and quantified by gas chromatography-mass spectrometer. Gut microbiota was evaluated by 16S rRNA gene sequencing.

RESULTS

Fecal SCFAs were negatively correlated with adiposity parameters including body mass index, visceral adipose tissue and waist circumference (all P < 0.05). Metastat analysis showed that the top 5 relatively abundant bacterial taxa of viscerally obese and non-obese groups were Bacteroides, Collinsella, Eubacterium rectale group, Lachnoclostridium, and Tyzzerella. Participants with visceral obesity had lower abundance of Bacteroides and Collinsella compared to non-obese patients (P < 0.05). Among them, the abundance of Collinsella was positively correlated with acetic acid concentrations (r = 0.63, P = 0.011). There were no significant intrapair differences in each SCFA concentrations between the twins in our study (P > 0.05).

CONCLUSION

Low fecal concentrations of SCFAs were associated with visceral obesity, and the gut microbiota might be involved in the underlying mechanism.

Toward more rigorous and informative nutritional epidemiology: The rational space between dismissal and defense of the status quo

To date, nutritional epidemiology has relied heavily on relatively weak methods including simple observational designs and substandard measurements. Despite low internal validity and other sources of bias, claims of causality are made commonly in this literature. Nutritional epidemiology investigations can be improved through greater scientific rigor and adherence to scientific reporting commensurate with research methods used. Some commentators advocate jettisoning nutritional epidemiology entirely, perhaps believing improvements are impossible. Still others support only normative refinements. But neither abolition nor minor tweaks are appropriate. Nutritional epidemiology, in its present state, offers utility, yet also needs marked, reformational renovation. Changing the status quo will require ongoing, unflinching scrutiny of research questions, practices, and reporting-and a willingness to admit that "good enough" is no longer good enough. As such, a workshop entitled "Toward more rigorous and informative nutritional epidemiology: the rational space between dismissal and defense of the status quo" was held from July 15 to August 14, 2020. This virtual symposium focused on: (1) Stronger Designs, (2) Stronger Measurement, (3) Stronger Analyses, and (4) Stronger Execution and Reporting. Participants from several leading academic institutions explored existing, evolving, and new better practices, tools, and techniques to collaboratively advance specific recommendations for strengthening nutritional epidemiology.

Integrative Review of Dietary Choice Revealed by fMRI: Considerations for Obesity Prevention and Weight-Loss Education

BACKGROUND

Emerging findings from neuroimaging studies investigating brain activity associated with dietary behavior are illuminating the interaction of biological and behavioral mechanisms that have implications for obesity prevention. Globally, A total of 1.9 billion adults are overweight, and 650 million are obese. Obesity and being overweight are major risk factors for chronic illness and death. Behaviorally based health interventions have had limited success in curbing the obesity epidemic. Greater understanding of brain responses to food cues will contribute to new knowledge and shape public health efforts in obesity prevention. However, an integration of this knowledge for obesity prevention education has not been published.

AIMS

This study links evidence generated from brain activation studies generated in response to diet and food images and highlights educational recommendations for nurses engaged in obesity prevention and weight-loss education.

METHODS

An integrative review of the literature was conducted using the MeSH keywords "magnetic resonance imaging," "diet," and "food images" in PubMed, MEDLINE Complete, CINAHL, and Cochrane databases from their first appearance in 2006 through March 2018. Studies published in English and using functional magnetic resonance imaging to measure brain response to diet, and food images were initially identified. Animal models, those whose primary focus was a specific disease, and intervention studies were excluded.

RESULTS

Of 159 studies identified, 26 met inclusion criteria. Findings from neuroimaging studies may help explain the relationship between brain mechanisms and behavioral aspects of dietary choice and inform patient education in obesity prevention. Awareness of this evidence is applicable to nursing education efforts. This review contributes several recommendations that should be considered by nurses providing individualized weight-loss education.

LINKING EVIDENCE TO ACTION

Nurses engaged in patient education for obesity prevention should consider personalized interventions that cultivate internal awareness for dietary adherence, self-care, exercise, hydration, and mood state; avoid using caloric deprivation approaches, such as skipping breakfast, for weight-loss interventions; and note the importance of individualized obesity prevention and weight-loss education.

Development of a Food-Based Diet Quality Score from a Short FFQ and Associations with Obesity Measures, Eating Styles and Nutrient Intakes in Finnish Twins

We constructed a food-based diet quality score (DQS) and examined its association with obesity measures, eating styles and nutrient intakes. Participants were 3592 individuals (764 dizygotic [DZ] and 430 monozygotic [MZ] twin pairs) from the FinnTwin16 study. The DQS (0–12 points) was constructed from a short 14 item food frequency questionnaire. Anthropometric measures and eating styles were self-reported. Nutrient intakes were calculated from food diaries completed in a subsample of 249 individuals (45 same-sex DZ and 60 MZ twin pairs). Twins were analyzed both as individuals and as twin pairs. The DQS was inversely associated with body mass index (β = −0.12, per one-unit increase in DQS, p < 0.001), waist circumference (β = −0.34, p < 0.001), obesity (odds ratio [OR]: 0.95, p = 0.004) and abdominal obesity (OR: 0.88, p < 0.001), independent of sex, age, physical activity and education. A higher DQS was associated with health-conscious eating, having breakfast, less snacking, fewer evening meals, and a higher frequency and regularity of eating. The DQS was positively correlated with the intakes of protein, fiber and magnesium and negatively correlated with the intakes of total fat, saturated fat and sucrose. Within twin pairs, most of the associations between the DQS with eating styles and some nutrients remained, but the DQS was not associated with obesity measures within twin pairs. The DQS is an easy-to-use tool for ranking adults according to diet quality and shows an association with obesity measures, eating styles and key nutrients in the expected direction.

Non-target impurity profiling of marketplace Cetirizine using high-resolution mass spectrometry and multivariate data analysis

RATIONALE

As always, drug impurity is the first concern of medication safety. The quality of pre- and post-marketed drugs is estimated through systematic analysis of potential hazardous substances by impurity profiling. Impurity profile is the general name of all unwanted materials which may affect the purity of an active pharmaceutical ingredient (API). The safety of original drugs is guaranteed by an enormous amount of animal experiments and clinical research while the safety of generic drugs should also be ensured by comparative analysis for consistency evaluation. The significantly differential impurities between them should be focused on and the toxicity should be further estimated if necessary. Herein, we take a marketplace drug named Cetirizine as an example to investigate if there was a method which could effectively discover the potential markers among Cetirizine tablets with different brands and describe specific impurity profiling which makes the unknown brand of Cetirizine tablets predictable.

METHODS

Liquid chromatography coupled with high-resolution mass spectrometry (LC/HRMS) was applied to capture the characteristic features of the impurity profile for three brands of marketplace Cetirizine tablets using full scan data-dependent MS/MS scan mode (FS-ddMS(2) ).

RESULTS

Unsupervised learning: principal component analysis (PCA) and supervised learning: consensus orthogonal partial least squares discriminant analysis (OPLS-DA) were utilized to reveal the essential character of Cetirizine impurity profile; 16 differential impurities were finally found, their structures were speculated by HRMS(2) data.

CONCLUSIONS

The cause of formation was further elucidated which gave a suggestion for production process optimization. Copyright © 2016 John Wiley & Sons, Ltd.