Adaptation of Temperate Seagrass to Arctic Light Relies on Seasonal Acclimatization of Carbon Capture and Metabolism

Due to rising global surface temperatures, Arctic habitats are becoming thermally suitable for temperate species. Whether a temperate species can immigrate into an ice-free Arctic depends on its ability to tolerate extreme seasonal fluctuations in daylength. Thus, understanding adaptations to polar light conditions can improve the realism of models predicting poleward range expansions in response to climate change. Plant adaptations to polar light have rarely been studied and remain unknown in seagrasses. If these ecosystem engineers can migrate polewards, seagrasses will enrich biodiversity, and carbon capture potential in shallow coastal regions of the Arctic. Eelgrass (Zostera marina) is the most widely distributed seagrass in the northern hemisphere. As the only seagrass species growing as far north as 70°N, it is the most likely candidate to first immigrate into an ice-free Arctic. Here, we describe seasonal (and diurnal) changes in photosynthetic characteristics, and in genome-wide gene expression patterns under strong annual fluctuations of daylength. We compared PAM measurements and RNA-seq data between two populations at the longest and shortest day of the year: (1) a Mediterranean population exposed to moderate annual fluctuations of 10–14 h daylength and (2) an Arctic population exposed to high annual fluctuations of 0–24 h daylength. Most of the gene expression specificities of the Arctic population were found in functions of the organelles (chloroplast and mitochondrion). In winter, Arctic eelgrass conserves energy by repressing respiration and reducing photosynthetic energy fluxes. Although light-reactions, and genes involved in carbon capture and carbon storage were upregulated in summer, enzymes involved in CO2 fixation and chlorophyll-synthesis were upregulated in winter, suggesting that winter metabolism relies not only on stored energy resources but also on active use of dim light conditions. Eelgrass is unable to use excessive amounts of light during summer and demonstrates a significant reduction in photosynthetic performance under long daylengths, possibly to prevent photoinhibition constrains. Our study identified key mechanisms that allow eelgrass to survive under Arctic light conditions and paves the way for experimental research to predict whether and up to which latitude eelgrass can potentially migrate polewards in response to climate change.

Inflammatory potential of diet and bone mineral density in a senior Mediterranean population: a cross-sectional analysis of PREDIMED-Plus study

Purpose Inflammation could play a key role in tissue damage and bone metabolism. The modified dietary inflammatory score (M-DIS) is a validated tool to estimate the inflammatory potential of the diet. In the present study, we evaluate the associations between the M-DIS and bone mineral density (BMD) in a senior Mediterranean population with overweight/obesity and metabolic syndrome. Methods Baseline cross-sectional association between the M-DIS and bone mineral density was assessed in 1134 participants of the multicenter PREDIMED-Plus trial (aged 55–75 with overweight/obesity and metabolic syndrome). BMD was measured using Dual-energy X-ray Absorptiometry scans and participants answered a food frequency questionnaire to determine the M-DIS. BMD was categorized as low BMD when T score was equal or lower than -1 and normal BMD in another case. Associations between BMD and M-DIS were evaluated by using linear and logistic regressions adjusted by other co-variates. Results Participants in the top tertile of the M-DIS had a lower BMD at total femur [β (95% CI) − 0.02 (− 0.04, − 0.01)], trochanter areas [β (95% CI) − 0.03 (− 0.05, − 0.01)] and lumbar spine area [β (95% CI) − 0.03 (− 0.07, 0.01)] (but in the last case, measures were less precise and hence not statistically significant) compared to those in the lower M-DIS tertile. Multiple logistic regression analyses showed that the odds of the total femur and femoral trochanter osteopenia/osteoporosis were higher in participants in the top tertile compared to those in the lowest tertile of M-DIS [OR (95% CI) 1.71 (1.12, 2.64), P for trend 0.015; 2.02 (1.29, 3.21), P for trend 0.002, respectively]. Conclusion A high pro-inflammatory diet, measured by the M-DIS, is associated with lower BMD in a senior Mediterranean population with metabolic syndrome.

Risk of Developing Metabolic Syndrome Is Affected by Length of Daily Siesta: Results from a Prospective Cohort Study

Background: Siesta has been associated with increased incidence of cardiovascular disease but the mechanism remains unclear. New studies into the relationship between siesta and metabolic syndrome have identified siesta length as a crucial differential, suggesting that siesta less than 40 min is associated with decreased risk of metabolic syndrome, while longer siesta is associated with increased risk. We aimed to investigate the effect of siesta duration on development of metabolic syndrome in a Mediterranean population using a prospective cohort study design. Methods: Our sample consisted of 9161 participants of the SUN cohort without components of metabolic syndrome at baseline. Siesta exposure was assessed at baseline and the development of metabolic syndrome components was assessed after an average 6.8 years of follow-up. We estimated odds ratios and fitted logistic regression models to adjust for potential cofounders including night-time sleep duration and quality, as well as other diet, health, and lifestyle factors. Results: We observed a positive association between average daily siesta >30 min and development of metabolic syndrome (aOR = 1.39 CI: 1.03–1.88). We found no significant difference in risk of developing metabolic syndrome between the group averaging ≤30 min of daily siesta and the group not taking siesta (aOR = 1.07 CI: 0.83–1.37). Further analysis suggested that average daily siesta <15 min may reduce risk of metabolic syndrome. Conclusions: Our study supports the J-curve model of the association between siesta and risk of metabolic syndrome, but suggests the protective effect is limited to a shorter range of siesta length than previously proposed.

Food protein induced allergic proctocolitis: The effect of maternal Mediterranean diet during pregnancy and breastfeeding

Background: The aim of the current investigation was to explore predisposing factors for food protein induced allergic proctocolitis (FPIAP) in Greek infants relevant in the maternal diet, during pregnancy and breastfeeding, as relevant knowledge is limited. Methods: A multicenter retrospective case-control study was conducted in 6 regions in Greece, with 96 mothers of infants with and 141 mothers of infants without a history of FPIAP. Maternal dietary habits during pregnancy and breastfeeding were evaluated with validated questionnaires: a) The Mediterranean Diet (MedDiet) Score, and b) The Mediterranean Oriented Culture Specific Semi-Quantitative Food Frequency Questionnaire. Statistical tests, modeling and exploration of the FPIAP risk in relation to the maternal diet using elastic net regression models were performed with R software and Studio. Results: FPIAP was associated with cow’s milk (83.6%), egg (7.3 %), and wheat, beef (6.4%) in the maternal diet. Adherence to MedDiet was similar among the mothers, but mothers of FPIAP infants consumed more vegetables (p=0.018) and olive oil (p=0.003). Elastic net prediction models showed that, in this Mediterranean population, increased consumption during pregnancy and lactation of common allergens, whole grain products, homemade food, fish and shellfish, fruit offered protection; conversely, high intake of vegetables, sugar and total fat, and non-stick/grilled cooking, increased the risk of FPIAP, as did high intake of salt and white flour during lactation. Conclusions: Components of a maternal Mediterranean diet can protect against FPIAP when traditional cooking methods are adopted and fish, fruit and whole wheat products are consumed frequently.

Spectrum of Mutations of Familial Mediterranean Fever Gene by Whole Sequencing Method in Iranian Patients

Background: Familial Mediterranean fever (FMF) is the most common type of periodic fever syndrome. The disease is most prevalent in the western Mediterranean population, but today it is widespread in the world due to the large ethnic migrations of Turks, Jews, Arabs and Armenians. The MEFV gene is the only gene known to be associated with the disease. Objectives: The aim of this study was to characterize pathogenic mutations in patients with typical FMF symptoms by sequencing the entire MEFV gene. Methods: This is a descriptive-analytical study that was performed during ten years from 2009 to 2019. On 252 patients after clinical diagnosis based on existing criteria to determine mutations referred to Tehran Medical Genetics Laboratory and the whole sequencing method for MEFV gene was used to determine mutations. Results: Out of 252 patients, 143 (56.7%) had pathogenic variants, and 109 (43.3%) had no variants reported as pathogenic mutations. Variants were identified as fallow: (1) 8.7% as homozygous; (2) 22.2% as compound heterozygous; (3) 25.7% as heterozygous. The most common variants were M694V (c.2080A > G) and E148Q (c.442G > C). Conclusions: This study showed that the age of onset of the disease was in the first and second decades of life amongst our patients and the most common complaints of patients were periodic fever and abdominal pain. The most frequent allele was M694V (c.2080A > G) followed by E148Q (c.442G > C) allele.

Increased Adiposity Appraised with CUN-BAE Is Highly Predictive of Incident Hypertension. The SUN Project

Overweight and obesity are growing worldwide and strongly associated with hypertension. The Clínica Universidad de Navarra-Body Adiposity Estimator (CUN-BAE) index is proposed as an optimal indicator of body fatness. We aimed to investigate the association of body fat as captured by the CUN-BAE index with incident hypertension in a Mediterranean population. We assessed 15,950 participants of the SUN (Seguimiento Universidad de Navarra) prospective cohort (63.7% women) initially free of hypertension. Participants completed follow-up questionnaires biennially. A validated 136-item food-frequency questionnaire was administered at baseline. We used Cox models adjusted for multiple confounders. Among 12.3 years of median follow-up (interquartile range: 8.3, 15.0 years), 2160 participants reported having received a diagnosis of hypertension. We observed a strong direct association between progressively higher the CUN-BAE index at baseline and incident hypertension during follow-up in multivariable-adjusted models for men and women, even after further adjustment for BMI ≥ 30 kg/m2, showing a significant association also in non-obese participants. For each 2-unit increase in the CUN-BAE index, hypertension risk increased by 27% and 29% in men and women, respectively. The results remained significant when considering longitudinal repeated measures of changes in body fat assessed with the CUN-BAE index among the different biennial follow-up questionnaires. Our results emphasize the importance of reducing and maintaining a low body fat to prevent hypertension.