Bone Marrow Adipocytes—Role in Physiology and Various Nutritional Conditions in Human and Animal Models

In recent years, adipose tissue has attracted a lot of attention. It is not only an energy reservoir but also plays important immune, paracrine and endocrine roles. BMAT (bone marrow adipose tissue) is a heterogeneous tissue, found mostly in the medullary canal of the long bones (tibia, femur and humerus), in the vertebrae and iliac crest. Adipogenesis in bone marrow cavities is a consequence of ageing or may accompany pathologies like diabetes mellitus type 1 (T1DM), T2DM, anorexia nervosa, oestrogen and growth hormone deficiencies or impaired haematopoiesis and osteoporosis. This paper focuses on studies concerning BMAT and its physiology in dietary interventions, like obesity in humans and high fat diet in rodent studies; and opposite: anorexia nervosa and calorie restriction in animal models.     

Reduction of Cardio-Metabolic Risk and Body Weight through a Multiphasic Very-Low Calorie Ketogenic Diet Program in Women with Overweight/Obesity: A Study in a Real-World Setting

Background: The prevention and treatment of obesity and its cardio-metabolic complications are relevant issues worldwide. Among lifestyle approaches, very low-calorie ketogenic diets (VLCKD) have been shown to lead to rapid initial weight loss, resulting in better long-term weight loss maintenance. As no information on VLCKD studies carried on in a real-world setting are available, we conducted this multi-centre study in a real-world setting, aiming at assessing the efficacy and the safety of a specific multiphasic VLCKD program in women with overweight or obesity. Methods: A multi-center, prospective, uncontrolled trial was conducted in 33 outpatient women (age range 27–60 y) with overweight or obesity (BMI: 30.9 ± 2.7 kg/m²; waist circumference: 96.0 ± 9.4 cm) who started a VLCKD dietary program (duration: 24 weeks), divided into four phases. The efficacy of VLCKD was assessed by evaluating anthropometric measures and cardiometabolic markers; liver and kidney function biomarkers were assessed as safety parameters. Results: The VLCKD program resulted in a significant decrease of body weight and BMI (−14.6%) and waist circumference (−12.4%). At the end of the protocol, 33.3% of the participants reached a normal weight and the subjects in the obesity range were reduced from 70% to 16.7%. HOMA-IR was markedly reduced from 3.17 ± 2.67 to 1.73 ± 1.23 already after phase 2 and was unchanged thereafter. Systolic blood pressure decreased after phase 1 (−3.5 mmHg) and remained unchanged until the end of the program. Total and LDL cholesterol and triglycerides were significantly reduced by VLCKD along with a significant HDL cholesterol increase. Liver, kidney and thyroid function markers did not change and remained within the reference range. Conclusions: The findings of a multi-center VLCKD program conducted in a real-world setting in a cohort of overweight/obese women indicate that it is safe and effective, as it results in a major improvement of cardiometabolic parameters, thus leading to benefits that span well beyond the mere body weight/adiposity reduction.     

POSITIVE AFFECT MODULATES ACTIVITY IN THE VISUAL CORTEX TO IMAGES OF HIGH CALORIE FOODS

Activity within the visual cortex can be influenced by the emotional salience of a stimulus, but it is not clear whether such cortical activity is modulated by the affective status of the individual. This study used functional magnetic resonance imaging (fMRI) to examine the relationship between affect ratings on the Positive and Negative Affect Schedule and activity within the occipital cortex of 13 normal-weight women while viewing images of high calorie and low calorie foods. Regression analyses revealed that when participants viewed high calorie foods, Positive Affect correlated significantly with activity within the lingual gyrus and calcarine cortex, whereas Negative Affect was unrelated to visual cortex activity. In contrast, during presentations of low calorie foods, affect ratings, regardless of valence, were unrelated to occipital cortex activity. These findings suggest a mechanism whereby positive affective state may affect the early stages of sensory processing, possibly influencing subsequent perceptual experience of a stimulus.     

Serum response of all-trans and 9-cis isomers of beta-carotene in humans.

Little work has been performed on the serum response of various carotene isomers. The present study was carried out to examine the serum response of all-trans and 9-cis isomers of beta-carotene (BC) using frequent blood sample collections at early time points.

Serum responses of all-trans BC and a mixture of BC isomers containing 80% 9-cis BC were studied in 15 men by measuring the serum concentrations of BC at 1, 3, 5, 7, 9, 12, and 24 hours after a single large oral dose of all-trans BC or 9-cis BC.

The serum response to an oral dose of all-trans BC (120 mg) significantly increased from baseline at 24 hr (p < 0.004). After an oral dose of a mixture of BC isomers (120 mg, 80% 9-cis BC), the peak concentration of 9-cis BC was significantly greater that baseline values (p < 0.016).

Increases in serum all-trans BC levels, in part, may be due to greater intestinal absorption, whereas the inability to measure a significant increase in the concentration of 9-cis BC may indicate poor absorption, isomerization to all-trans BC, or a very rapid tissue uptake.     

The Effect of Meal Replacement on Weight Loss According to Calorie-Restriction Type and Proportion of Energy Intake: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

BackgroundPortion control is a useful component of weight reduction interventions and meal replacement (MR) plans represent a promising strategy for portion control. Research performed with pooled data on the effect of MR plans according to various characteristics of MR interventions remains scarce.ObjectiveOur aim was to assess the effects of MR-based diets compared with food-based diets on weight loss, according to calorie-restriction types and energy intake proportions from MR.MethodsElectronic databases (Cochrane Central Register of Controlled Trials, PubMed, Embase, and Research Information Sharing Service) were searched for randomized controlled trials on weight loss results of MR-based calorie-restricted diets compared with food-based calorie-restricted diets from January 2000 to May 2020. Standardized mean differences (Hedges' g) from all study outcomes were calculated using a random-effects model. Heterogeneity was quantified by Q test and I². Publication bias was assessed using a funnel plot and a trim and fill method. Both interventions (MR and control) were separated into very-low-energy diets and low-energy diets (LEDs). A meta-analysis of variance was conducted by dividing patient-related factors and treatment-related factors into subgroups. In multivariable meta-regressions, background variables were selected first, after which main independent variables were included.ResultsTwenty-two studies involving 24 interventions and 1,982 patients who were overweight or obese were included. The effect size in which MR-based LED was compared with food-based LED for weight loss was small, favoring MR (Hedges’ g = 0.261; 95% CI 0.156 to 0.365; I² = 21.9; 95% CI 0.0 to 53.6). Diets including ≥60% of total daily energy intake from MR had a medium effect size favoring MR with regard to weight loss among the groups (Hedges’ g = 0.545; 95% CI 0.260 to 0.830; I² = 42.7; 95% CI 0.0 to 80.8).ConclusionsThe effect of MR-based LED on weight loss was superior to the effect of food-based LED, and receiving ≥60% of total daily energy intake from MR had the greatest effect on weight loss.     

短期极低热量饮食干预对住院超重及肥胖患者的疗效及患者依从性

目的：探讨住院超重及肥胖患者短期进行极低热量饮食干预的效果及其依从性。方法：选择2015年11月至2016年11月在复旦大学附属中山医院内分泌科住院治疗的30例超重及肥胖患者作为研究对象,住院期间给予每日总热量800 kcal（1 kcal=4.186 8 kJ）的饮食干预。比较其入院当日和出院当日的体质量,并观察患者住院期间对极低热量饮食的耐受性,随访患者出院半年内饮食控制和体质量情况。结果：患者平均接受(8±3) d的极低热量饮食干预后,体质量显著下降［(92.86±22.78) kg vs (95.93±23.28) kg,P<0.001］。所有患者均无干预相关严重不良反应;患者住院期间可坚持极低热量饮食治疗,但在出院后长期依从性较差。结论：短期极低热量饮食干预可有效降低超重肥胖患者的体质量,患者耐受性好,但对长期极低热量饮食依从性较差,应加强患者饮食控制。     

我院新生儿肠外营养处方的合理性分析

目的：评价我院新生儿肠外营养三种固定组套处方临床实际应用的合理性。方法：收集2018年1-7月我院NICU的新生儿肠外营养处方共320份,患儿共52例,其中早产儿38例,足月儿14例。对新生儿肠外营养三种固定组套处方的成分进行分析,统计患儿的住院时间、使用TPN的时间、患儿摄入的液体量、热卡量、血糖、肝功能等,并结合患儿的生长发育情况,来评价三种固定组套处方的合理性。结果：三种固定组套处方在临床应用中的稳定性能够得到保证,糖速、热氮比、电解质浓度均在合理范围内,但52例患儿中存在3例前期液体量摄入过多,320份处方中存在114份热卡摄入不足,早产儿组套处方中缺少电解质钠和镁,足月儿组套中缺少电解质镁等。结论：我院新生儿肠外营养三种固定组套处方在临床的实际应用中,能够基本满足大多数新生儿的生长发育需求,但肠外营养处方存在热卡和蛋白质摄入不足,需要进一步完善。     

Calorie restriction and sirtuins revisited

Calorie or dietary restriction (CR) has attracted attention because it is the oldest and most robust way to extend rodent life span. The idea that the nutrient sensors, termed sirtuins, might mediate effects of CR was proposed 13 years ago and has been challenged in the intervening years. This review addresses these challenges and draws from a great body of new data in the sirtuin field that shows a systematic redirection of mammalian physiology in response to diet by sirtuins. The prospects for drugs that can deliver at least a subset of the benefits of CR seems very real.