Mitochondrial metabolism and neuroinflammation in the cerebral cortex and cortical synapses of rats: effect of milk intake through DNA methylation

Brain plasticity and cognitive functions are tightly influenced by foods or nutrients, which determine a metabolic modulation having a long-term effect on health, involving also epigenetic mechanisms. Breast milk or formula based on cow milk is the first food for human beings, who, throughout their lives, are then exposed to different types of milk. We previously demonstrated that rats fed with milk derived from distinct species, with different compositions and nutritional properties, display selective modulation of systemic metabolic and inflammatory profiles through changes of mitochondrial functions and redox state in liver, skeletal and cardiac muscle. Here, in a rat model, we demonstrated that isoenergetic supplementation of milk from cow (CM), donkey (DM) or human (HM) impacts mitochondrial functions and redox state in the brain cortex and cortical synapses, affecting neuroinflammation and synaptic plasticity. Interestingly, we found that the administration of different milk modulates DNA methylation in rat brain cortex and consequently affects gene expression. Our results emphasize the importance of nutrition in brain and synapse physiology, and highlight the key role played in this context by mitochondria, nutrient-sensitive organelles able to orchestrate metabolic and inflammatory responses.

Mitochondria: the gatekeepers between metabolism and immunity

Metabolism and immunity are crucial monitors of the whole-body homeodynamics. All cells require energy to perform their basic functions. One of the most important metabolic skills of the cell is the ability to optimally adapt metabolism according to demand or availability, known as metabolic flexibility. The immune cells, first line of host defense that circulate in the body and migrate between tissues, need to function also in environments in which nutrients are not always available. The resilience of immune cells consists precisely in their high adaptive capacity, a challenge that arises especially in the framework of sustained immune responses. Pubmed and Scopus databases were consulted to construct the extensive background explored in this review, from the Kennedy and Lehninger studies on mitochondrial biochemistry of the 1950s to the most recent findings on immunometabolism. In detail, we first focus on how metabolic reconfiguration influences the action steps of the immune system and modulates immune cell fate and function. Then, we highlighted the evidence for considering mitochondria, besides conventional cellular energy suppliers, as the powerhouses of immunometabolism. Finally, we explored the main immunometabolic hubs in the organism emphasizing in them the reciprocal impact between metabolic and immune components in both physiological and pathological conditions.

Hepatocyte Aquaporins AQP8 and AQP9 Are Engaged in the Hepatic Lipid and Glucose Metabolism Modulating the Inflammatory and Redox State in Milk-Supplemented Rats

Milk is an important source of nutrients and energy, but there are still many uncertainties regarding the health effects of milk and dairy products consumption. Milk from different species varies in physicochemical and nutritional properties. We previously showed that dietary supplements with different milks in rats trigger significant differences in metabolic and inflammatory states, modulating mitochondrial functions in metabolically active organs such as the liver and skeletal muscle. Here, we have deepened the effects of isoenergetic supplementation of milk (82 kJ) from cow (CM), donkey (DM) or human (HM) on hepatic metabolism to understand the interlink between mitochondrial metabolic flexibility, lipid storage and redox state and to highlight the possible role of two hepatocyte aquaporins (AQPs) of metabolic relevance, AQP8 and AQP9, in this crosstalk. Compared with rats with no milk supplementation, DM- and HM-fed rats had reduced hepatic lipid content with enhanced mitochondrial function and decreased oxidative stress. A marked reduction in AQP8, a hydrogen peroxide channel, was seen in the liver mitochondria of DM-fed rats compared with HM-fed, CM-fed and control animals. DM-fed or HM-fed rats also showed reduced hepatic inflammatory markers and less collagen and Kupffer cells. CM-fed rats showed higher hepatic fat content and increased AQP9 and glycerol permeability. A role of liver AQP8 and AQP9 is suggested in the different metabolic profiles resulting from milk supplementation.

A Bioelectrical Impedance Analysis in Adult Subjects: The Relationship between Phase Angle and Body Cell Mass

The correct assessment of body composition is essential for an accurate diagnostic evaluation of nutritional status. The body mass index (BMI) is the most widely adopted indicator for evaluating undernutrition, overweight, and obesity, but it is unsuitable for differentiating changes in body composition. In recent times, bioelectrical impedance analyses (BIA) have been proven as a more accurate procedure for the assessment of body composition. Furthermore, the efficiency of bioelectrical impedance vector analyses, as an indicator of nutritional status and hydration, has been demonstrated. By applying a bioimpedance analysis, it is possible to detect fat mass (FM), fat free mass (FFM), phase angle, and body cell mass (BCM). It is important to point out that phase angle and BCM are strongly associated with health status. The aim of this research was to examine body composition and the association between the phase angle and BCM in 87 subjects (14 males and 73 females), aged between 23 and 54 years, with BMIs ranging from 17.0 to 32.0 kg/m2, according to sex. The BMI results revealed that the majority of the assessed subjects were within the normal range and had a normal percentage of FM. Our data indicate that a direct relation exists between phase angle and cellular health and that these values increase almost linearly. Consequently, a high phase angle may be related to increased BCM values.

From Obesity-Induced Low-Grade Inflammation to Lipotoxicity and Mitochondrial Dysfunction: Altered Multi-Crosstalk between Adipose Tissue and Metabolically Active Organs

Obesity is a major risk factor for several metabolic diseases, including type 2 diabetes, hyperlipidemia, cardiovascular diseases, and brain disorders. Growing evidence suggests the importance of inter-organ metabolic communication for the progression of obesity and the subsequent onset of related disorders. This review provides a broad overview of the pathophysiological processes that from adipose tissue dysfunction leading to altered multi-tissue crosstalk relevant to regulating energy homeostasis and the etiology of obesity. First, a comprehensive description of the role of adipose tissue was reported. Then, attention was turned toward the unhealthy expansion of adipose tissue, low-grade inflammatory state, metabolic inflexibility, and mitochondrial dysfunction as root causes of systemic metabolic alterations. In addition, a short spot was devoted to iron deficiency in obese conditions and the role of the hepcidin-ferroportin relationship in the management of this issue. Finally, different classes of bioactive food components were described with a perspective to enhance their potential preventive and therapeutic use against obesity-related diseases.

Impedance Analysis to Evaluate Nutritional Status in Physiological and Pathological Conditions

A thorough knowledge of body composition assessment techniques is the cornerstone for initiating a customized nutritional program. The second step is to consider the potential of their application in different physiological and pathological conditions and their effectiveness in the management of a monitoring pathway during dietary interventions. To date, bioimpedance analysis is the most effective and reliable method for assessing body composition due to its advantages in terms of speed of execution, non-invasiveness and low cost. Therefore, this review article aims to analyze the main concepts and application areas of bioimpedance measurement techniques, in particular vector frequency-based analysis (BIVA) systems, in order to assess their validity in both physiological and pathological conditions.

Invited review: Human, cow, and donkey milk comparison: Focus on metabolic effects

Milk is an important food of the daily diet. Many countries include it in their dietary recommendations due to its content in several important nutrients that exert beneficial effects on human health. Human milk is a newborn's first food and plays an important role in the growth, development, and future health of every individual. Cow milk is the type of milk most consumed in the world. However, its relatively high content of saturated fats raises concerns about potential adverse effects on human health, although epidemiological studies have disproved this association. Indeed, dairy consumption appear to be linked to a lower risk of mortality and major cardiovascular disease events. In the last few years many researchers have begun to focus their attention on both the production and quality of cow milk as well as the analysis of milk from other animal species to evaluate their effect on human health. The need to investigate the composition and metabolic effects of milk from other animal species arises from the adverse reactions of individuals in several groups to certain components of cow milk. It has emerged that donkey milk compared with that of other animal species, is the nearest to human milk and an excellent substitute for it. Milk from various animal species shows substantial differences in nutritional composition and distinct metabolic effects. In this review, we discussed the main compositional features and metabolic effects of 3 types of milk: human, cow, and donkey milk.

Role of Milk Micronutrients in Human Health

The aim of this review is to provide an overview of different compositions, in terms of main minerals and vitamins, of milk from animal species that represent the most common source of this food for humans, highlighting the uniqueness of nutritional qualities linked to animal species. It is known that milk is an important and valuable food for human nutrition, representing an excellent source of nutrients. Indeed, it contains both macronutrients (proteins, carbohydrates, and fat) that contribute to its nutritive and biological value and micronutrients represented by minerals and vitamins, which play a relevant role in the body's various vital functions. Although their supply is represented by small quantities, vitamins and minerals are important components for a healthy diet. Milk composition in terms of minerals and vitamins differs between various animal species. Micronutrients are important components for human health as their deficiency is causes of malnutrition. Furthermore, we report on the most significant metabolic and beneficial effects of certain micronutrients in the milk, emphasizing the importance of this food for human health and the need for some milk enrichment procedures with the most relevant micronutrients to human health.

Butyrate Improves Neuroinflammation and Mitochondrial Impairment in Cerebral Cortex and Synaptic Fraction in an Animal Model of Diet-Induced Obesity

Neurodegenerative diseases (NDDs) are characterized by cognitive impairment and behavioural abnormalities. The incidence of NDDs in recent years has increased globally and the pathological mechanism is not fully understood. To date, plentiful evidence has showed that metabolic alterations associated with obesity and related issues such as neuroinflammation, oxidative stress and mitochondrial dysfunction may represent an important risk factor, linking obesity and NDDs. Numerous studies have indicated a correlation between diet and brain activities. In this context, a key role is played by mitochondria located in the synaptic fraction; indeed, it has been shown that high-fat diets cause their dysfunction, affecting synaptic plasticity. In this scenario, the use of natural molecules that improve brain mitochondrial function represents an important therapeutic approach to treat NDDs. Recently, it was demonstrated that butyrate, a short-chain fatty acid is capable of counteracting obesity in an animal model, modulating mitochondrial function. The aim of this study has been to evaluate the effects of butyrate on neuroinflammatory state, oxidative stress and mitochondrial dysfunction in the brain cortex and in the synaptic fraction of a mouse model of diet-induced obesity. Our data have shown that butyrate partially reverts neuroinflammation and oxidative stress in the brain cortex and synaptic area, improving mitochondrial function and efficiency.

The Hepatic Mitochondrial Alterations Exacerbate Meta-Inflammation in Autism Spectrum Disorders

The role of the liver in autism spectrum disorders (ASD), developmental disabilities characterized by impairments in social interactions and repetitive behavioral patterns, has been poorly investigated. In ASD, it has been shown a dysregulation of gut-brain crosstalk, a communication system able to influence metabolic homeostasis, as well as brain development, mood and cognitive functions. The liver, with its key role in inflammatory and metabolic states, represents the crucial metabolic organ in this crosstalk. Indeed, through the portal vein, the liver receives not only nutrients but also numerous factors derived from the gut and visceral adipose tissue, which modulate metabolism and hepatic mitochondrial functions. Here, we investigated, in an animal model of ASD (BTBR mice), the involvement of hepatic mitochondria in the regulation of inflammatory state and liver damage. We observed increased inflammation and oxidative stress linked to hepatic mitochondrial dysfunction, steatotic hepatocytes, and marked mitochondrial fission in BTBR mice. Our preliminary study provides a better understanding of the pathophysiology of ASD and could open the way to identifying hepatic mitochondria as targets for innovative therapeutic strategies for the disease.

Heart Mitochondrial Metabolic Flexibility and Redox Status Are Improved by Donkey and Human Milk Intake

The biological mechanisms linking nutrition and antioxidants content of the diet with cardiovascular protection are subject of intense investigation. It has been demonstrated that dietary supplementation with cow, donkey or human milk, characterized by distinct nutritional properties, triggers significant differences in the metabolic and inflammatory status through the modulation of hepatic and skeletal muscle mitochondrial functions. Cardiac mitochondria play a key role for energy-demanding heart functions, and their disfunctions is leading to pathologies. Indeed, an altered heart mitochondrial function and the consequent increased reactive oxygen species (ROS) production and inflammatory state, is linked to several cardiac diseases such as hypertension and heart failure. In this work it was investigated the impact of the milk consumption on heart mitochondrial functions, inflammation and oxidative stress. In addition, it was underlined the crosstalk between mitochondrial metabolic flexibility, lipid storage and redox status as control mechanisms for the maintenance of cardiovascular health.

Milk Fatty Acid Profiles in Different Animal Species: Focus on the Potential Effect of Selected PUFAs on Metabolism and Brain Functions

Milk contains several important nutrients that are beneficial for human health. This review considers the nutritional qualities of essential fatty acids (FAs), especially omega-3 (ω-3) and omega-6 (ω-6) polyunsaturated fatty acids (PUFAs) present in milk from ruminant and non-ruminant species. In particular, the impact of milk fatty acids on metabolism is discussed, including its effects on the central nervous system. In addition, we presented data indicating how animal feeding—the main way to modify milk fat composition—may have a potential impact on human health, and how rearing and feeding systems strongly affect milk quality within the same animal species. Finally, we have presented the results of in vivo studies aimed at supporting the beneficial effects of milk FA intake in animal models, and the factors limiting their transferability to humans were discussed.

Dietary Micronutrient Management to Treat Mitochondrial Dysfunction in Diet-Induced Obese Mice

Obesity and associated metabolic disturbances, which have been increasing worldwide in recent years, are the consequences of unhealthy diets and physical inactivity and are the main factors underlying non-communicable diseases (NCD). These diseases are now responsible for about three out of five deaths worldwide, and it has been shown that they depend on mitochondrial dysfunction, systemic inflammation and oxidative stress. It was also demonstrated that several nutritional components modulating these processes are able to influence metabolic homeostasis and, consequently, to prevent or delay the onset of NCD. An interesting combination of nutraceutical substances, named DMG-gold, has been shown to promote metabolic and physical wellness. The aim of this research was to investigate the metabolic, inflammatory and oxidative pathways modulated by DMG-gold in an animal model with diet-induced obesity. Our data indicate that DMG-gold decreases the metabolic efficiency and inflammatory state and acts as an antioxidant and detoxifying agent, modulating mitochondrial functions. Therefore, DMG-gold is a promising candidate in the prevention/treatment of NCD.

Effect of bempedoic acid on uric acid and gout in 3621 patients with hypercholesterolemia: pooled analyses from phase 3 trials

Background

Bempedoic acid (BA), an oral ATP-citrate lyase inhibitor, significantly lowers low-density lipoprotein cholesterol levels in patients with hypercholesterolemia. In clinical trials of BA, small mean increases in uric acid have been reported. BA weakly inhibits organic anion transporter 2 (OAT2) in vitro, which may account for small elevations in serum uric acid.

Purpose

To assess uric acid levels and incidence of gout with BA treatment.

Methods

Data were pooled from 4 randomized (2:1), double-blind studies of BA (180 mg daily) vs placebo for 12 weeks to 52 weeks in patients with hypercholesterolemia on stable background lipid-lowering therapy. Safety assessments included adverse events of special interest (elevation in uric acid levels, gout) and laboratory assessments.

Results

A total of 2424 patients treated with BA and 1197 patients on placebo were included in this analysis. Mean (SD) baseline uric acid levels were 6.0 (1.4) mg/dL for both groups. History of gout was reported by 5.2% (127/2424) and 5.8% (69/1197) in the BA and placebo groups, respectively. At week 12, mean (SD) serum uric acid levels (% change from baseline) increased from baseline with BA treatment by 0.82 (0.97) mg/dL (14.8%) vs –0.02 (0.82) mg/dL (0.67%) for placebo. Elevations in serum uric acid levels typically occurred within the first 4 weeks of treatment, remained stable during treatment, and returned to baseline after treatment discontinuation. Gout was reported in 1.4% (BA) and 0.4% (placebo) of patients, and hyperuricemia was reported in 1.7% (BA) and 0.6% (placebo) of patients. Other potential clinical consequences of elevated uric acid levels (eg, events associated with nephrolithiasis), were similar between groups (0.7% vs 0.8%). In both groups, patients who reported gout during the studies were more likely to have a medical history of gout or elevated baseline uric acid levels (Table). Few patients discontinued treatment due to gout (n=1, <0.1% [BA]) or uric acid increases (n=2, <0.1% [BA]).

Conclusion

Mean increases in uric acid levels were small, remained stable while patients continued to receive treatment, were infrequently associated with AEs, and were reversible on discontinuation of BA

Funding Acknowledgement

Type of funding source: Private company. Main funding source(s): Esperion Therapeutics funded the research for this study and provided writing support for this abstract. Medical writing assistance was provided by Agnella Izzo Matic, PhD, CMPP, and Kelly M Cameron, PhD, CMPP, of JB Ashtin.

Neurodevelopmental Disorders: Effect of High-Fat Diet on Synaptic Plasticity and Mitochondrial Functions

Neurodevelopmental disorders (NDDs) include diverse neuropathologies characterized by abnormal brain development leading to impaired cognition, communication and social skills. A common feature of NDDs is defective synaptic plasticity, but the underlying molecular mechanisms are only partially known. Several studies have indicated that people’s lifestyles such as diet pattern and physical exercise have significant influence on synaptic plasticity of the brain. Indeed, it has been reported that a high-fat diet (HFD, with 30–50% fat content), which leads to systemic low-grade inflammation, has also a detrimental effect on synaptic efficiency. Interestingly, metabolic alterations associated with obesity in pregnant woman may represent a risk factor for NDDs in the offspring. In this review, we have discussed the potential molecular mechanisms linking the HFD-induced metabolic dysfunctions to altered synaptic plasticity underlying NDDs, with a special emphasis on the roles played by synaptic protein synthesis and mitochondrial functions.

Decreased Metabolic Flexibility in Skeletal Muscle of Rat Fed with a High-Fat Diet Is Recovered by Individual CLA Isomer Supplementation via Converging Protective Mechanisms

Energy balance, mitochondrial dysfunction, obesity, and insulin resistance are disrupted by metabolic inflexibility while therapeutic interventions are associated with improved glucose/lipid metabolism in skeletal muscle. Conjugated linoleic acid mixture (CLA) exhibited anti-obesity and anti-diabetic effects; however, the modulatory ability of its isomers (cis₉, trans₁₁, C9; trans₁₀, cis₁₂, C10) on the metabolic flexibility in skeletal muscle remains to be demonstrated. Metabolic inflexibility was induced in rat by four weeks of feeding with a high-fat diet (HFD). At the end of this period, the beneficial effects of C9 or C10 on body lipid content, energy expenditure, pro-inflammatory cytokines, glucose metabolism, and mitochondrial efficiency were examined. Moreover, oxidative stress markers, fatty acids, palmitoyletanolamide (PEA), and oleyletanolamide (OEA) contents along with peroxisome proliferator-activated receptors-alpha (PPARα), AKT, and adenosine monophosphate-activated protein kinase (AMPK) expression were evaluated in skeletal muscle to investigate the underlying biochemical mechanisms. The presented results indicate that C9 intake reduced mitochondrial efficiency and oxidative stress and increased PEA and OEA levels more efficiently than C10 while the anti-inflammatory activity of C10, and its regulatory efficacy on glucose homeostasis are associated with modulation of the PPARα/AMPK/pAKT signaling pathway. Our results support the idea that the dissimilar efficacy of C9 and C10 against the HFD-induced metabolic inflexibility may be consequential to their ability to activate different molecular pathways.

The Role of Red Yeast Rice Based Preparations for Non-Pharmacological Correction of Dyslipidemia in Patients with Low and Moderate Cardiovascular Risk (Expert Opinion)

The Russian Federation is among countries with high cardiovascular risk. Hypercholesterolemia is a leading risk factor for the development of atherosclerotic cardiovascular diseases. To achieve low-density lipoprotein cholesterol (LDL-C) targets, such approaches as lifestyle changes and pharmacological correction, based on the use of statins, are applied. At the same time, a significant proportion of the population has moderate hypercholesterolemia and is characterized by low or moderate cardiovascular risk. Although first-line recommendations should be followed, a healthy lifestyle alone is not enough to achieve target levels of LDL-C, which means that even people with low to moderate risk may end up with the prospect of lifelong therapy with lipid-lowering drugs. These individuals do not have an indication for lipid-lowering therapy, and they are usually recommended a change in diet and supplementation. Innovative nutritional strategies have been developed to manage dyslipidemia. They were based either on changing some “risky” food components or on encouraging the consumption of “healthy” functional foods and/or nutraceuticals. Nutraceuticals (registered as food supplements in Russia) is an innovative way to help control LDL-C at low and moderate risk individuals without lipid-lowering drugs and as nutritive support for the cholesterol-lowering diet. Red yeast rice (RYR) based preparations have been already developed and available at the moment. RYR based preparations can be considered in patients with low and moderate cardiovascular risk, who have not reached the target level of LDL-C and have no indications for statin therapy or have statin intolerance. RYR based preparations contains a statin-like substance monacolin K in a dose of 3 mg. In randomized clinical trials, it was proved that the use of high-quality RYR nutraceutical leads to a decrease in LDL-C by an average of 20% without increasing the risk of side effects like for statins. Evaluation of dietary supplements and functional foods should necessarily include not only evidence of beneficial effects with respect to effects on the lipid profile and atherosclerosis, but also proven good tolerability. The manufacturing standard for these products is also important, guaranteeing component standardization and quality. RYR analogues should guarantee the absence of mycotoxin in their composition. In Russia, programs are needed for the primary prevention of atherosclerotic cardiovascular diseases with effects on hypercholesterolemia at the population level.

High-Fat Diet Induces Neuroinflammation and Mitochondrial Impairment in Mice Cerebral Cortex and Synaptic Fraction

Brain mitochondrial dysfunction is involved in the development of neurological and neurodegenerative diseases. Mitochondria specifically located at synapses play a key role in providing energy to support synaptic functions and plasticity, thus their defects may lead to synaptic failure, which is a common hallmark of neurodegenerative diseases. High-Fat Diet (HFD) consumption increases brain oxidative stress and impairs brain mitochondrial functions, although the underlying mechanisms are not completely understood. The aim of our study is to analyze neuroinflammation and mitochondrial dysfunctions in brain cortex and synaptosomal fraction isolated from a mouse model of diet-induced obesity. Male C57Bl/6 mice were divided into two groups fed a standard diet or HFD for 18 weeks. At the end of the treatment, inflammation (detected by ELISA), antioxidant state (measured by enzymatic activity), mitochondrial functions and efficiency (detected by oxidative capacity and Seahorse analysis), and brain-derived neurotrophic factor (BDNF) pathway (analyzed by western blot) were determined in brain cortex and synaptosomal fraction. In HFD animals, we observed an increase in inflammatory parameters and oxidative stress and a decrease in mitochondrial oxidative capacity both in the brain cortex and synaptosomal fraction. These alterations parallel with modulation of BDNF, a brain key signaling molecule that is linking synaptic plasticity and energy metabolism. Neuroinflammation HFD-dependent negatively affects BDNF pathway and mitochondrial activity in the brain cortex. The effect is even more pronounced in the synaptic region, where the impaired energy supply may have a negative impact on neuronal plasticity.

Milk From Cow Fed With High Forage/Concentrate Ratio Diet: Beneficial Effect on Rat Skeletal Muscle Inflammatory State and Oxidative Stress Through Modulation of Mitochondrial Functions and AMPK Activity

Milk and dairy products are relevant components of daily diet and are part of dietary recommendation in many countries due to their content of key nutrients. However, the relatively high content of saturated fat of the milk and its extensive usage for every age group raises concerns about its potential negative health effects. Therefore, in the last years, several researchers dedicated their attention to milk production and quality. Milk fatty acids profile depend on cow feeding and in particular on the type of forage and concentrate and forage/concentrate ratio. It was demonstrated that feeding dairy cows with a 70/30 forage/concentrate ratio yields milk with a low ω6:ω3 ratio and high CLA levels. In this work, we demonstrated that the supplementation of rats diet with this high forage milk (HFM) results, in the skeletal muscle of these animals, in a reduced lipid content and inflammation levels, and an improved mitochondrial lipid oxidation, and redox status through modulation of AMPK activity.

Hemispheric Asymmetries in Radial Line Bisection: Role of Retinotopic and Spatiotopic Factors

Previous studies showed that healthy individuals bisect radial lines oriented along the midsagittal plane farther than the true center (distal bisection bias). It was proposed that the distal bisection bias depended on the presence of an attention bias directed toward far space (distal attention bias) and that this bias is related to the activity of the occipitotemporal visual processing stream. Other studies have also suggested that a similar distal attention bias is linked to the activity of the right hemisphere. In the present experiment we investigated whether distal bisection bias increased when radial lines were placed in the left hemispace. Furthermore, we also examined whether the bisection bias was enhanced by the use of the left hand, as left hand movements are mainly controlled by the right hemisphere. Right-handed participants were asked to bisect radial lines presented below eye level along the midsagittal plane (central lines), or laterally and parallel to the midsagittal plane, in the left or right hemispace (left and right lines, respectively). Participants used their right or left hand. The results showed that participants consistently bisected left and central radial lines farther than (i) the true center and (ii) the subjective midpoint of right radial lines. Conversely, they bisected accurately right radial lines. The hand did not influence bisection error. The present study suggests that the distal bisection bias found in the bisection of left radial lines might depend on the presence of a distal attention bias related to right hemisphere activity. The relative contribution of retinotopic and spatiotopic factors in producing the distal bisection bias is discussed.

Long Feeding High-Fat Diet Induces Hypothalamic Oxidative Stress and Inflammation, and Prolonged Hypothalamic AMPK Activation in Rat Animal Model

Scope: The hypothalamus is a key brain region involved in the control of feeding and energy expenditure. Hypothalamic inflammation and oxidative stress are landmarks of both obesity and aging processes, although the molecular mechanisms are still unknown. Therefore, with the aim to understand the neurobiological mechanisms of energy homeostasis during aging, we evaluate the effects of long feeding high-fat diet (HFD) in rats, at different age, on modulation of hypothalamic molecular pathway, oxidative stress, and inflammation.

Procedures: Male Wistar rats were divided into two groups: control group, receiving standard diet (CD), and treated group, receiving HFD. Both groups were treated with the appropriate diet for 1, 3, 6, 12, or 18 weeks. We investigated energy balance and body composition, as well as lipid profile, homeostatic model assessment index, and inflammatory state in serum. Furthermore, we also analyzed, at hypothalamic level, inflammation and oxidative stress, and adenosine monophosphate-dependent kinase (AMPK) and pAMPK expression levels.

Results: Our data showed that aging and HFD induce increased energy intake and energy efficiency and decreased energy expenditure associated, at hypothalamic level, with inflammation and oxidative stress and activation of AMPK.

Conclusion: Our results indicate that the age at which HFD feeding starts and the diet duration are critical in obesity development. The prolonged activation of hypothalamic AMPK may be related to the alterations in energy homeostasis.

EXPERT CONSENSUS. ROLE OF COMBINATION LIPID-LOWERING THERAPY (SIMVASTATIN/EZETIMIBE 20/10 MG) IN THE CORRECTION OF LIPID METABOLISM DISTURBANCES IN PATIENTS WITH CHRONIC KIDNEY DISEASE

Expert Consensus. Role of combination lipid-lowering therapy (simvastatin/ezetimibe 20/10 mg) in the correction of lipid metabolism disturbances in patients with chronic kidney disease.

High cell density cultivation of Escherichia coli K4 in a microfiltration bioreactor: a step towards improvement of chondroitin precursor production

Background

The bacteria Escherichia coli K4 produces a capsular polysaccharide (K4 CPS) whose backbone is similar to the non sulphated chondroitin chain. The chondroitin sulphate is one of the major components of the extra-cellular matrix of the vertebrate connective tissues and a high value molecule, widely employed as active principle in the treatment of osteoarthritis. It is usually obtained by extraction from animal tissues, but the risk of virus contaminations, as well as the scarceness of raw material, makes this productive process unsafe and unable to satisfy the growing market demand. In previous studies a new biotechnological process to produce chondroitin from Escherichia coli K4 capsular polysaccharide was investigated and a 1.4 g·L^-1 K4 CPS concentration was reached using fed-batch fermentation techniques. In this work, on the trail of these results, we exploited new fermentation strategies to further improve the capsular polysaccharide production.

Results

The inhibitory effect of acetate on the bacterial cells growth and K4 CPS production was studied in shake flask conditions, while a new approach, that combined the optimization of the feeding profiles, the improvement of aeration conditions and the use of a microfiltration bioreactor, was investigated in three different types of fermentation processes. High polysaccharide concentrations (4.73 ± 0.2 g·L^-1), with corresponding average yields (0.13 ± 0.006 g_{K4 CPS}·g_cdw^-1), were obtained; the increase of K4 CPS titre, compared to batch and fed-batch results, was of 16-fold and 3.3-fold respectively, while average yield was almost 3.5 and 1.4 fold higher.

Conclusion

The increase of capsular polysaccharide titre confirmed the validity of the proposed fermentation strategy and opened the way to the use of the microfiltration bioreactor for the biotechnological production of chondroitin.

High-yield cultivation of Marinococcus M52 for production and recovery of hydroxyectoine

Ectoine and hydroxyectoine, produced by Halomonas ssp. and Marinococcus ssp., have been extensively characterized and proposed for biotechnological applications. Large-scale production of ectoine was achieved by implementing the so-called "milking process" by Bitop (Witten, Germany) and commercializing compatible solutes as stabilizers for biological systems. However, there is a continuing interest in optimization of the production process for hydroxyectoine alone, as the latter was shown to have greater stabilization capacity. Recently, Marinococcus strain M52 was selected for its ability to convert most ectoine into hydroxyectoine during a prolonged stationary phase. This study reports on the correlation between growth conditions and hydroxyectoine production in Marinococcus M52 cultivation. We demonstrated that a dissolved oxygen content higher than 10% during cultivation leads to more rapid accumulation of hydroxyectoine than of ectoine (with hydroxyectoine up to 1.6 g l-1). In addition, we employed a microfiltration bioprocess to improve biomass and yield of products (reaching 3.6 g l-1 of hydroxyectoine). Finally, we developed a novel extraction method based on osmotic down-shock coupled with thermal permeabilization to recover the desired products from the biomass.

Acute Effect of High-Fat Meal on Endothelial Function in Moderately Dyslipidemic Subjects

OBJECTIVE

Hypercholesterolemia markedly impairs endothelial function. Whether this is the case for hypertriglyceridemia is less clear, however, and limited evidence exists on the effect of an acute increase in triglyceridemia caused by a high-fat meal.

METHODS AND RESULTS

In 16 normotensive subjects with an untreated mild hypertriglyceridemia and dyslipidemia and in 7 normal controls, we measured radial artery diameter and blood flow by an echo-tracking device (NIUS02). Data were obtained at baseline, at the release of a 4-minute ischemia of the hand, which causes an increase in arterial diameter dependent on nitric oxide (NO) secretion, and at the release of a 12-minute exclusion of the arm by an arm cuff to obtain a larger increase in arterial diameter mainly of nonendothelial nature. Measurements were performed before and 6 hours after a high-fat meal (680 kcal/m(2) body surface; 82% lipids). In mild dyslipidemic hypertriglyceridemic subjects, the high-fat meal did not alter baseline blood pressure (beat-to-beat finger measurement), heart rate, radial artery diameter, and blood flow. It also did not alter the increase in blood flow induced by the 4-minute ischemia (+42.7+/-10.4 and +43.7+/-10.4 mL/min), whereas it markedly attenuated the concomitant increase in arterial diameter (+0.31+/-0.06 versus 0.13+/-0.06 mm; P<0.05). The alteration of the diameter response did not correlate with changes in total cholesterol, but it showed a significant correlation with the increase in serum triglycerides induced by high-fat meal (r=0.49, P<0.05). This attenuation was not seen in control subjects and in subjects in whom measurements were repeated after a 6-hour observation period. It was also not paralleled by an alteration of the endothelially independent response to a 12-minute ischemia whose larger effects on arterial diameter and blood flow were similar before and after the high-fat meal.

CONCLUSIONS

Endothelial function is markedly impaired by a high-fat meal that causes an acute hypertriglyceridemia. This impairment is evident in dyslipidemic patients with baseline hypertriglyceridemia but not in normotriglyceridemic controls. An oral fat load was administered to 55 HIV-positive and 10 HIV-negative individuals. Postprandial clearance of triglyceride-rich lipoproteins was delayed in HIV-positive individuals. Compared with HIV-positive subjects not on PIs, those taking PIs do not have increased postprandial triglyceride-rich lipoproteins but do have increased postprandial intermediate-density and low-density lipoproteins. Hypercholesterolemia impairs endothelial function, whereas the effect of hypertriglyceridemia is less clear. In normotensive subjects with an untreated hypertriglyceridemia and hypercholesterolemia, we measured endothelial function before and 6 hours after a high-fat meal. The results demonstrate that in moderately dyslipidemic patients, endothelial function is impaired by acute hypertriglyceridemia.

The effect of gemfibrozil on lipid profile and glucose metabolism in hypertriglyceridaemic well-controlled non-insulin-dependent diabetic patients. For the Gemfibrozil Study Group

We assessed the efficacy of gemfibrozil therapy on lipid profile and glucose metabolism in a large cohort of (type 2) non-insulin-dependent diabetic patients. We enrolled 217 type 2 diabetic patients with plasma triglyceride concentrations equal to or above 2 mmol/l: 110 were randomized to gemfibrozil (600 mg twice daily) and 107 to placebo treatment in a double blind fashion. Each treatment was followed for 20 weeks. To assess postprandial glucose metabolism and insulin secretion, at time 0 and 20 weeks, a standard meal containing 12.5 g of proteins, 40.1 g of carbohydrate, 10 g of lipids was given. No differences in demographic characteristics were observed between patients randomized either to gemfibrozil or to placebo therapy. No differences were observed in total cholesterol and LDL-cholesterol concentration changes between the baseline observations and week 20 of both treatments. At variance, both treatments significantly increased HDL cholesterol. Gemfibrozil treatment significantly decreased plasma triglyceride concentration from 316+/-84 to 214+/-82 mg/dl (P < 0.001), whereas with placebo triglyceride levels increased from 318 + 93 to 380 + 217 mg/dl. No changes were observed in non-esterified fatty acid concentrations or in fasting plasma glucose concentrations, in HbA(1C) values, insulin and C-peptide concentrations. Gemfibrozil treatment: 1) significantly reduces circulating triglyceride concentration; 2) does not significantly affect cholesterol concentration; 3) does not worsen glucose metabolism.

A collaborative trial for the evaluation of blood cholesterol measurement in clinical laboratories in Italy

A collaborative trial for the evaluation of blood cholesterol measurement in Italy was carried out, with the use of two lyophilized controls, whose target values, respectively 4.42 and 6.21 mmol/l, were established by means of "definitive" methodology (isotope dilution/mass spectrometry). Results from 480 participants showed a somewhat broad dispersion (CV 6.1% and 6.3% respectively), and a definite bias (-0.25 mmol/l and -0.61 mmol/l respectively) with respect to the target values. The different analytical systems were characterized by different combinations of inaccuracy and imprecision; however, the bias observed for the higher concentration sample was a constant finding. The behaviour of the control materials, in comparison with that exhibited by patients' sera, was assessed in a manual enzymatic procedure and in the Kodak Ektachem 700 and Technicon Chem 1 systems. The peculiar property of one control material to behave differently from patients' sera in some analytical systems, i.e. the lack of commutability, was found to be partially responsible for the observed bias in the three methods studied. The importance of testing for commutability of the control materials to be used for the control of accuracy is stressed.

Lecithin cholesterol acyl transferase deficiency: molecular analysis of a mutated allele

The enzyme, lecithin cholesterol acyltransferase (LCAT), is responsible for the esterification of plasma cholesterol mediating the transfer of an acyl group from lecithin to the 3-hydroxy group of cholesterol. Deficiency of the enzyme is a well-known syndrome with a widespread geographic occurrence. We have cloned an allele from a patient homozygous for the LCAT deficiency. The only change that we could detect is a C to T transition in the fourth exon of the gene; this causes a substitution of Arg for Trp at position 147 of the mature protein. The functional significance of such a substitution with respect to the enzyme defect was demonstrated by transfecting the mutated LCAT gene in the cell line COS-1.

Effects of anabolic steroids, testosterone, and HGH on blood lipids and echocardiographic parameters in body builders

To evaluate the metabolic or cardiovascular effects induced by self-administration of human growth hormone (HGH) alone or combined with testosterone and anabolic steroids, we conducted a study with 15 male body builders. Of these, 8 (control group) did not take any hormonal substances; 6 (experimental group) self-administered testosterone, anabolic steroids, and HGH for 6 weeks in various dosages; 1 subject self-administered only HGH for an equal period of time. At the end of the period of treatment with the hormonal combination, the experimental group continued for 2 additional weeks with anabolic steroids and testosterone only. All maintained the same, unaltered type and intensity of training, and constant diet. Before the beginning of treatment with hormonal substances, after 6 weeks, and at the end of treatment (for a total of 8 weeks), they were tested for total and HDL-cholesterol (t-chol and HDL-chol), apolipoproteins A-1 and B (apo A-1 and B), and triglycerides (tg). Before the start and after 6 weeks, an echocardiographic examination was performed to assess left ventricular dimensions and function in all 15 body builders. The most interesting result is a significant decrease of HDL-chol and apo A-1 derived from self-administration of anabolic steroids and HGH together.

A study of the structure of the gene for lecithin: cholesterol acyltransferase in four unrelated individuals with familial lecithin: cholesterol acyltransferase deficiency

1. We have used polyclonal antibodies and a complementary DNA clone for human lecithin:cholesterol acyltransferase (LCAT) to study LCAT protein and the structure of the LCAT gene, respectively, in patients with familial LCAT deficiency from Norway, Ireland, Germany and Italy. 2. The patients had low levels of non-functional LCAT protein in their serum as measured by rocket immunoelectrophoresis; its mol. wt. of approximately 68,000 was identical with that of LCAT in normal plasma, as judged by immunoblotting. 3. Enzymatic digestion of DNA samples from the patients produced LCAT gene fragments which were indistinguishable from those found in normal individuals. 4. We conclude that LCAT deficiency in these patients is not caused by a large deletion or rearrangement of the LCAT gene sequences.