Mediterranean Diet Favors Vitamin K Intake: A Descriptive Study in a Mediterranean Population

The Mediterranean diet (MD) is associated with improved longevity and the prevention and management of chronic inflammatory diseases (CIDs). Vitamin K, which is present in MD core components such as leafy green vegetables, is also known as a protective factor for CIDs. Estimates of vitamin K intake in Mediterranean settings are still scarce, and the association between MD and vitamin K intake is yet to be established. This study analyzed vitamin K intake and MD adherence in the Algarve region, in Portugal. We conducted a cross-sectional study in a nonrandom sample of adults using an online questionnaire which included a validated food-frequency questionnaire and a screener for MD adherence. A total of 238 participants were recruited (68% women and 32% men). Adherence to the MD was low (11%). Only 10% of the participants had vitamin K intake below the adequate intake. Adherence to the MD was positively correlated with vitamin K intake (r = 0.463; p < 0.001) and age (r = 0.223; p < 0.001). Our findings underscore the importance of promoting adherence to the MD for optimal vitamin K intake, and future research should focus on developing effective interventions to promote this dietary pattern, particularly among younger individuals and men.

A guide to the use of bioassays in exploration of natural resources

Bioassays are the main tool to decipher bioactivities from natural resources thus their selection and quality are critical for optimal bioprospecting. They are used both in the early stages of compounds isolation/purification/identification, and in later stages to evaluate their safety and efficacy. In this review, we provide a comprehensive overview of the most common bioassays used in the discovery and development of new bioactive compounds with a focus on marine bioresources. We present a comprehensive list of practical considerations for selecting appropriate bioassays and discuss in detail the bioassays typically used to explore antimicrobial, antibiofilm, cytotoxic, antiviral, antioxidant, and anti-ageing potential. The concept of quality control and bioassay validation are introduced, followed by safety considerations, which are critical to advancing bioactive compounds to a higher stage of development. We conclude by providing an application-oriented view focused on the development of pharmaceuticals, food supplements, and cosmetics, the industrial pipelines where currently known marine natural products hold most potential. We highlight the importance of gaining reliable bioassay results, as these serve as a starting point for application-based development and further testing, as well as for consideration by regulatory authorities.

New Food Frequency Questionnaire to Estimate Vitamin K Intake in a Mediterranean Population

Vitamin K is a multifunctional micronutrient essential for human health, and deficiency has been linked to multiple pathological conditions. In this study, we aimed to develop and validate a new food frequency questionnaire (FFQ) to estimate total vitamin K intake, over the course of a 30-day interval, in a Portuguese, Mediterranean-based, population. We conducted a prospective study in a non-random sample of 38 healthy adult volunteers. The FFQ was designed based on a validated Portuguese FFQ used in nationally representative studies and on literature reviews, to include foods containing ≥5 μg of vitamin K/100 g and foods with a lower vitamin K content, yet commonly included in a Mediterranean diet. Vitamin K intake was estimated from 24 h recalls and six days of food records. The final FFQ included 54 food items which, according to regression analyses, explains 90% of vitamin K intake. Mean differences in vitamin K intake based on food records (80 ± 47.7 μg/day) and on FFQ (96.5 ± 64.3 μg/day) were statistically non-significant. Further, we found a strong correlation between both methods (r = 0.7; p = 0.003). Our results suggest that our new FFQ is a valid instrument to assess the last 30 days of vitamin K intake in the Portuguese Mediterranean population.

P0873GLA-RICH PROTEIN (GRP) AS AN EARLY AND NOVEL MARKER ASSOCIATED WITH VASCULAR CALCIFICATION AND CKD-MINERAL AND BONE DISORDER (MBD) IN DIABETIC PATIENTS WITH CKD: A PILOT COHORT STUDY

Background and Aims

Cardiovascular disease (CVD) is the most life-threatening complication in chronic kidney disease (CKD) patients. In addition to traditional risk factors, most patients with CKD display abnormal mineral metabolism with underlying hormonal dysregulation, defined as chronic kidney disease-mineral and bone disorder (CKD-MBD). CKD-MBD involves changes in mineral ion homeostasis, bone quality and turnover, cardiovascular and soft tissue calcifications, which highly contribute for cardiovascular complications. Vascular calcification (VC) is associated with significant morbidity and mortality and a strong predictor of cardiovascular risk in CKD patients. Early preventive measures, including new diagnostic/prognostic tools, are required to reduce the development and progression of VC, left ventricular hypertrophy and arterial stiffness, which are crucial for the prevention of CVD outcomes in CKD patients. Gla-rich protein (GRP) is a vitamin K-dependent protein with a dual capacity to function as an inhibitor of pathological calcification and anti-inflammatory agent in the cardiovascular system, whose clinical utility is unknown. Our aim with this study was to evaluate the potential of GRP as a new marker for CKD-MBD and vascular calcification, in type 2 diabetic patients with chronic kidney disease (CKD) stages 2-4.

Method

In an observational prospective study including all eligible type 2 diabetic patients with CKD stages 2-4 (n=80) followed in outpatient nephrology consultation from 2010 to 2017, we explored correlations between levels of GRP in serum with mineral metabolism and inflammation markers, CKD developmental stage, vascular calcification and pulse pressure (PP). Vascular calcification score (VCS) was evaluated using the plain x-ray of the hands and pelvis (Adragão score), and increased cardiovascular risk was considered for VCS≥3. Measurements of GRP in serum were performed using a recently developed sandwich ELISA assay. Descriptive statistics, ANOVA and post hoc analysis with Scheffe test were used for analysis. Forward stepwise logistic regression (likelihood ratio) analysis was applied to identify predictive factors for VCS and PP, and ROC curves were used to assess the sensitivity and specificity of GRP in relation to these exposure factors.

Results

Spearman’s correlation analysis revealed the strong positive correlation between levels of serum GRP and eGFR (r=0.863, p&lt;0.0001) and α klotho (r=0.647, p&lt;0.0001), while a negative correlation with phosphate (P) (r=-0.715, &lt;0.0001), FGF23 (r=-0.676, &lt;0.0001), VCS (r=-0.822, p&lt;0.0001), PP (r=-0.533, p&lt;0.0001), calcium x phosphate (CaxP) (r=-0.302, p=0.006) and IL-6 (r=-0.349, p=0.002). Serum GRP levels were found to progressively decreased from stage 2 to stage 4 CKD. Multivariate analysis identified low levels of eGFR and GRP, and high levels of FGF-23 as independent risk factors for both the VCS and PP. The area under the ROC curves for GRP was 0.865±0.046, 95% CI (0.776-0.955), p&lt;0.0001 for VCS and 0.782±0.054, 95% CI (0.677-0.887), p&lt;0.0001 for PP.

Conclusion

Reduced levels of GRP were associated with higher levels of vascular calcification promoters such as P, FGF-23 and CaxP, and with lower levels of the VC inhibitor α-Klotho, indicating a correlation between GRP and the dysregulation of phosphate metabolism characteristic of CKD-MBD. In addition, this pilot cohort study indicates that GRP levels might be a significant clinical predictor of vascular calcifications in diabetic patients with CKD.

Funding

This research was funded by the Portuguese Society of Nephrology (SPN) through project funding 2016, by the Portuguese national funds from FCT - Foundation for Science and Technology through the transitional provision DL57/2016/CP1361/CT0006 and project UID/Multi/04326/2019.

Acknowledgments

To SPN by the attribution of the Jacinto Simões award (2018) financed by Fresenius medical care.

The interplay between mineral metabolism, vascular calcification and inflammation in Chronic Kidney Disease (CKD): challenging old concepts with new facts

Chronic kidney disease (CKD) is one of the most powerful predictors of premature cardiovascular disease (CVD), with heightened susceptibility to vascular intimal and medial calcification associated with a high cardiovascular mortality. Abnormal mineral metabolism of calcium (Ca) and phosphate (P) and underlying (dys)regulated hormonal control in CKD-mineral and bone disorder (MBD) is often accompanied by bone loss and increased vascular calcification (VC). While VC is known to be a multifactorial process and a major risk factor for CVD, the view of primary triggers and molecular mechanisms complexity has been shifting with novel scientific knowledge over the last years. In this review we highlight the importance of calcium-phosphate (CaP) mineral crystals in VC with an integrated view over the complexity of CKD, while discuss past and recent literature aiming to highlight novel horizons on this major health burden. Exacerbated VC in CKD patients might result from several interconnected mechanisms involving abnormal mineral metabolism, dysregulation of endogenous calcification inhibitors and inflammatory pathways, which function in a feedback loop driving disease progression and cardiovascular outcomes. We propose that novel approaches targeting simultaneously VC and inflammation might represent valuable new prognostic tools and targets for therapeutics and management of cardiovascular risk in the CKD population.

Approaching families for organ donation-intensivists' perspectives

In Australia the initial approach to families for organ donation is almost always undertaken by intensivists. There is, however, a paucity of literature on intensivists' views on this approach and how their approach compares with recommendations in published literature on this subject. This study consisted of a survey of the views of intensive care consultants and senior intensive care registrars in the four major teaching hospitals in Perth, Western Australia, on how they approached families for organ donation. The study also includes a review of recently published literature on approaching families for organ donation. The survey results indicate that most intensive care consultants felt adequately trained to approach families for organ donation, but almost half of the group surveyed would prefer a collaborative approach with either a donor co-ordinator or a colleague with additional training on this subject. Despite recommendations in the literature and from the Australian and New Zealand Intensive Care Society to determine the registration status of potential donors on the Australian Organ Donation Registry prior to discussions with families, this was not always undertaken. In addition, the benefits of organ donation were not always discussed with families, nor were the reasons for refusal of consent sensitively explored.

Levosimendan in acute pulmonary embolism

Levosimendan has been used successfully in the treatment of ischaemic cardiac failure and myocardial stunning. There is growing evidence from both human and animal experiments that levosimendan has particularly favourable effects on the right ventricle. We describe a case of life-threatening pulmonary embolus supported by the use of levosimendan.

Cardiac arrest: a late complication of glucose-insulin-potassium (GIK) therapy

Rebound hyperkalaemia 4 hours after discontinuation of a glucose-insulin-potassium infusion inhibited an already compromised conduction system leading to ventricular standstill in a 41 year old man after re-do aortic valve surgery. Resuscitation was successful and allowed him to return from Australia to his home on Christmas Island. Glucose-insulin-potassium (GIK) infusions to reduce myocardial hypo-/re-perfusion injury after myocardial infarction, during coronary artery surgery and cardiopulmonary bypass are becoming more popular. There may also be a role for GIK in the treatment of refractory dysrhythmias and for myocardial protection in the brain-dead patient. However, these infusions are not without hazard and this report of rebound hyperkalaemia and cardiac arrest is unlikely to remain isolated.