Protein and vitamin B6 intake are associated with liver steatosis assessed by transient elastography, especially in obese individuals

Vitamin B6 deficiency produces metabolic alterations in Drosophila

INTRODUCTION

Pyridoxal 5'-phosphate (PLP), the biologically active form of vitamin B6 is involved in 4% of cellular enzymatic activities and its deficiency is responsible for or contributes to several human diseases. The study of underlying mechanisms is still in its infancy and requires suitable model organisms. In Drosophila the deficiency of vitamin B6 produces chromosome aberrations and hallmarks of human diseases including diabetes and cancer. However, the effects of vitamin B6 deficiency have never been examined at a metabolic level.

OBJECTIVES

This study evaluates the metabolic changes in vitamin B6 deficient Drosophila larvae with the aim of validating flies as a suitable model for diseases associated to vitamin B6 deficiency.

METHODS

To induce vitamin B6 deficiency we fed Drosophila wild type larvae with 4-deoxypyridoxine (4DP), a PLP antagonist. By HPLC analysis we verified that the 4DP treatment was effective in inducing vitamin B6 deficiency. Using an NMR-based metabolomic approach we compared the metabolites in larval extracts from untreated and 4DP-fed larvae.

RESULTS

The NMR spectra analysis identified quantitative differences for sixteen metabolites out of forty, including branched chain and aromatic amino acids, glucose, and lipids, thus revealing interesting possible associations with the phenotypes showed by vitamin B6 deficient flies.

CONCLUSIONS

Our results validate Drosophila as a suitable model to study in depth the molecular mechanisms underlying human diseases associated with vitamin B6 deficiency and confirmed that 4DP treatment is effective in inducing vitamin B6 deficiency.

The gut microbiota-produced vitamin B6 mitigates alcohol-associated liver disease by attenuating hepatic oxidative stress damage

BACKGROUND

Alcohol-associated liver disease (ALD) is a major clinical issue characterized by progressive stages, including hepatic steatosis, liver fibrosis, cirrhosis, and HCC. Patients with long-term chronic alcoholism often present with gut microbiota dysbiosis and reduced plasma levels of vitamin B6. This study aimed to verify that gut microbiota disruption in ALD significantly contributes to reduced in vivo production of vitamin B6 and to investigate the role of this reduction in the pathogenesis of ALD.

METHODS

The ALD was investigated utilizing the Gao-binge mouse model. Fecal microbial composition was analyzed in pair-fed mice and ALD mice to identify alcohol-induced functional changes in the microbiota. Additionally, liver protein expression profiles and liver and plasma metabolomic profiles were characterized to elucidate the role of vitamin B6 in ALD pathogenesis through integrated proteomic and metabolomic analyses. The findings were further validated using animal models and clinical patient samples.

RESULTS

Alcohol consumption disrupted the gut microbiota in the mice, impairing the vitamin B6 synthesis by intestinal microorganisms. Vitamin B6 deficiency aggravated the disorder of amino acid metabolism in the liver and inhibited ornithine aminotransferase expression, thereby worsening oxidative stress damage. In patients with ALD, significant disturbances of gut microbiota were observed, along with decreased intestinal vitamin B6 levels, which were negatively correlated with serum biochemical markers.

CONCLUSIONS

The imbalance of gut microbiota in ALD mice reduces vitamin B6 synthesis, which affects amino acid metabolism and glutathione synthesis in the liver, thereby exacerbating ALD. These findings suggest that vitamin B6 may play a critical protective role in ALD progression by regulating amino acid metabolism.

Vitamin B6 and diabetes and its role in counteracting advanced glycation end products

Naturally occurring forms of vitamin B6 include six interconvertible water-soluble compounds: pyridoxine (PN), pyridoxal (PL), pyridoxamine (PM), and their respective monophosphorylated derivatives (PNP, PLP, and PMP). PLP is the catalytically active form which works as a cofactor in approximately 200 reactions that regulate the metabolism of glucose, lipids, amino acids, DNA, and neurotransmitters. Most of vitamers can counteract the formation of reactive oxygen species and the advanced glycation end-products (AGEs) which are toxic compounds that accumulate in diabetic patients due to prolonged hyperglycemia. Vitamin B6 levels have been inversely associate with diabetes, while vitamin B6 supplementation reduces diabetes onset and its vascular complications. The mechanisms at the basis of the relation between vitamin B6 and diabetes onset are still not completely clarified. In contrast more evidence indicates that vitamin B6 can protect from diabetes complications through its role as scavenger of AGEs. It has been demonstrated that in diabetes AGEs can destroy the functionality of macromolecules such as protein, lipids, and DNA, thus producing tissue damage that result in vascular diseases. AGEs can be in part also responsible for the increased cancer risk associated with diabetes. In this chapter the relationship between vitamin B6, diabetes and AGEs will be discussed by showing the acquired knowledge and questions that are still open.

Supplementation of Micro- and Macronutrients-A Role of Nutritional Status in Non-Alcoholic Fatty Liver Disease

Non-alcoholic fatty liver disease (NAFLD) is a condition in which the pathological cumulation of fat with coexisting inflammation and damage of hepatic cells leads to progressive dysfunctions of the liver. Except for the commonly well-known major causes of NAFLD such as obesity, dyslipidemia, insulin resistance, or diabetes, an unbalanced diet and imbalanced nutritional status should also be taken into consideration. In this narrative review, we summarized the current knowledge regarding the micro- and macronutrient status of patients suffering from NAFLD considering various diets and supplementation of chosen supplements. We aimed to summarize the knowledge indicating which nutritional impairments may be associated with the onset and progression of NAFLD at the same time evaluating the potential therapy targets that could facilitate the healing process. Except for the above-mentioned objectives, one of the most important aspects of this review was to highlight the possible strategies for taking care of NAFLD patients taking into account the challenges and opportunities associated with the micronutrient status of the patients. The current research indicates that a supplementation of chosen vitamins (e.g., vitamin A, B complex, C, or D) as well as chosen elements such as zinc may alleviate the symptoms of NAFLD. However, there is still a lack of sufficient data regarding healthy ranges of dosages; thus, further research is of high importance in this matter.

Examining the Pathogenesis of MAFLD and the Medicinal Properties of Natural Products from a Metabolic Perspective

Metabolic-associated fatty liver disease (MAFLD), characterized primarily by hepatic steatosis, has become the most prevalent liver disease worldwide, affecting approximately two-fifths of the global population. The pathogenesis of MAFLD is extremely complex, and to date, there are no approved therapeutic drugs for clinical use. Considerable evidence indicates that various metabolic disorders play a pivotal role in the progression of MAFLD, including lipids, carbohydrates, amino acids, and micronutrients. In recent years, the medicinal properties of natural products have attracted widespread attention, and numerous studies have reported their efficacy in ameliorating metabolic disorders and subsequently alleviating MAFLD. This review aims to summarize the metabolic-associated pathological mechanisms of MAFLD, as well as the natural products that regulate metabolic pathways to alleviate MAFLD.

Associations between one-carbon metabolism and valproic acid-induced liver dysfunction in epileptic patients

Valproic acid (VPA) has been widely used as an antiepileptic drug for decades. Although VPA is effective and well-tolerated, long-term VPA treatment is usually associated with hepatotoxicity. However, the underlying mechanisms of VPA-caused hepatotoxicity remain unclear. In this study, a total of 157 pediatric patients with epilepsy were recruited and divided into normal liver function (NLF, 112 subjects) group and abnormal liver function (ABLF, 45 subjects) group. We observed that MTHFR A1298C and MTHFR C677T variants may be linked to VPA-induced liver dysfunction (p = 0.001; p = 0.023, respectively). We also found that the MTHFR A1298C polymorphism was associated with a higher serum Hcy level (p = 0.001) and a lower FA level (p = 0.001). Moreover, the serum Hcy levels was strongly correlated with the GSH and TBARS concentrations (r = -0.6065, P < 0.001; r = 0.6564, P < 0.001, respectively). Furthermore, logistic analysis indicated that MTHFR A1298C/C677T polymorphisms and increased Hcy concentrations may be risk factors for VPA-induced liver dysfunction. These results suggested that individual susceptibility to VPA-induced liver dysfunction may result from MTHFR A1298C/C677T polymorphisms and increased Hcy levels. This study may be helpful for the prevention and guidance of VPA-induced liver dysfunction.

A nutraceutical with Citrus bergamia and Cynara cardunculus improves endothelial function in adults with non-alcoholic fatty liver disease

OBJECTIVE

Polyphenol intake may prevent hepatic steatosis and cardiovascular disease by potentially improving endothelial function. The purposes of this study are to investigate the association between fatty liver disease and endothelial dysfunction and to test the effects of a nutraceutical containing extracts made from Citrus bergamia and Cynara cardunculus on peripheral vascular endothelial function in adults with liver steatosis.

METHODS

We analyzed data from 32 individuals with hepatic steatosis and endothelial dysfunction (reactive hyperemia index ≤ 1.67). Sixteen subjects took 1 capsule/d (300 mg/d) containing Cynara cardunculus extract and bergamot polyphenol fraction, while the other 16 subjects matched for age, sex, and body mass index took 1 capsule/d of placebo (maltodextrin) for 12 wk. All anthropometric parameters were assessed at baseline and after 12 wk as were lipids, glucose, and reactive hyperemia index using an EndoPAT 2000.

RESULTS

The mean age was 52 ± 9 y. The mean reactive hyperemia index was 1.15 ± 0.4. After 12 wk, we found a greater increase in reactive hyperemia index in the participants taking the nutraceutical rather than placebo (0.58 ± 0.5 versus 0.13 ± 0.5; P = 0.02, respectively). The stepwise multivariable analysis confirmed a positive association between reactive hyperemia index change and the nutraceutical treatment (B = 0.38; P = 0.025) and negative association with reactive hyperemia index values at baseline (B = -0.81; P < 0.001). No association was found between the reduction in the amount of intrahepatic fat and the improvement of endothelial function (B = 0.002; P = 0.56).

CONCLUSIONS

A nutraceutical containing bergamot and artichoke extracts improves peripheral vascular endothelial function in adults with hepatic steatosis and early phase of atherosclerosis.

Citrus Bergamia and Cynara Cardunculus Reduce Serum Uric Acid in Individuals with Non-Alcoholic Fatty Liver Disease

Background and Objectives: Hyperuricemia and liver steatosis are risk factors for cardiovascular diseases and mortality. The use of natural compounds could be a safe and effective alternative to drugs for the treatment of fatty liver and hyperuricemia. Polyphenolic fraction of Citrus Bergamia in association with the extract of Cynara Cardunculus, as nutraceutical, is able to reduce body weight, hepatic steatosis and markers of oxidative stress. Then, we performed a secondary analysis of a double-blind placebo-controlled trial to examine the effects of this nutraceutical on serum uric acid levels in adults with fatty liver. Materials and Methods: The study included 94 individuals with hepatic steatosis. For six weeks, the intervention group was given a nutraceutical (300 mg/day) comprising a Bergamot polyphenol fraction and Cynara Cardunculus extract. The control group received a daily pill of placebo. Serum uric acid, lipids, glucose and anthropometric parameters were assessed at baseline and after 6 weeks. Results: We found a greater reduction in serum uric acid in the participants taking the nutraceutical rather than placebo (−0.1 ± 0.7 mg/dL vs. 0.3 ± 0.7 mg/dL, p = 0.004), and especially in those with moderate/severe hepatic steatosis also after adjustment for confounding variables. In addition, we analysed the two groups according to tertiles of uric acid concentration. Among participants taking the nutraceutical, we found in those with the highest baseline serum uric acid (>5.4 mg/dL) the greater reduction compared to the lowest baseline uric acid (−7.8% vs. +4.9%; adjusted p = 0.04). The stepwise multivariable analysis confirmed the association between the absolute serum uric acid change and nutraceutical treatment (B = −0.43; p = 0.004). Conclusions: A nutraceutical containing bioactive components from bergamot and wild cardoon reduced serum uric acid during 6 weeks in adults with fatty liver. Future investigations are needed to evaluate the efficacy of this nutraceutical in the treatment of hyperuricaemia.

Hepatoprotective Effects of Ixeris chinensis on Nonalcoholic Fatty Liver Disease Induced by High-Fat Diet in Mice: An Integrated Gut Microbiota and Metabolomic Analysis

Ixeris chinensis (Thunb.) Nakai (IC) is a folk medicinal herb used in Mongolian medical clinics for the treatment of hepatitis and fatty liver diseases even though its pharmacological mechanism has not been well characterized. This study investigated the hepatoprotective mechanism of IC on mice with nonalcoholic fatty liver disease (NAFLD) by integrating gut microbiota and metabolomic analysis. A high-fat diet (HFD) was used to develop nonalcoholic fatty liver disease, after which the mice were treated with oral IC (0.5, 1.5 and 3.0 g/kg) for 10 weeks. HFD induced NAFLD and the therapeutic effects were characterized by pathological and histological evaluations, and the serum indicators were analyzed by ELISA. The gut microbial and metabolite profiles were studied by 16S rRNA sequencing and untargeted metabolomic analysis, respectively. The results showed that the administration of IC resulted in significant decreases in body weight; liver index; serum biomarkers such as ALT, TG, and LDL-C; and the liver inflammatory factors IL-1β, IL-6, and TNF-α. The 16S rRNA sequencing results showed that administration of IC extract altered both the composition and abundance of the gut microbiota. Untargeted metabolomic analysis of liver samples detected a total of 212 metabolites, of which 128 were differentially expressed between the HFD and IC group. IC was found to significantly alter the levels of metabolites such as L-glutamic acid, pyridoxal, ornithine, L-aspartic acid, D-proline, and N4-acetylaminobutanal, which are involved in the regulation of glutamine and glutamate, Vitamin B6 metabolism, and arginine and proline metabolic pathways. Correlation analysis indicated that the effects of the IC extract on metabolites were associated with alterations in the abundance of Akkermansiaceae, Lachnospiraceae, and Muribaculaceae. Our study revealed that IC has a potential hepatoprotective effect in NAFLD and that its function might be linked to improvements in the composition of gut microbiota and their metabolites.

A promising antifibrotic drug, pyridoxamine attenuates thioacetamide-induced liver fibrosis by combating oxidative stress, advanced glycation end products, and balancing matrix metalloproteinases

Liver fibrosis is a common chronic hepatic disease. This study was done to examine the effect of pyridoxamine against thioacetamide-induced hepatic fibrosis. Animals were divided into four groups (1) control group; (2) Thioacetamide group (200 mg/kg, i.p.) twice a week for eight weeks; (3) Pyridoxamine-treated group treated with pyridoxamine (100 mg/kg/day, i.p.) for eight weeks; (4) Thioacetamide and pyridoxamine group, in which pyridoxamine was given (100 mg/kg/day, i.p.) during thioacetamide injections. Thioacetamide treatment resulted in hepatic dysfunction manifested by increased serum levels of bilirubin, gamma-glutamyl transferase (GGT), alanine aminotransferase (ALT), and aspartate aminotransferase (AST). Oxidative stress was noted by increased hepatic lipid peroxidation and decreased glutathione (GSH). Increased concentrations of total nitrite/nitrate, advanced glycation end products (AGEs), monocyte chemoattractant protein-1 (MCP-1), tumor necrosis factor-α (TNF-α), transforming growth factor-β (TGF-β), matrix metalloproteinases (MMP-2&9) and tissue inhibitor of metalloproteinase-1 (TIMP-1) were noticed in hepatic tissues. Immunostaining sections also revealed overexpression of MMP-2, MMP-9 and collagen IV. Liver fibrosis was confirmed by severe histopathological changes. Pyridoxamine improved the assessed parameters. Moreover, histopathological and immunohistological studies supported the ability of pyridoxamine to reduce liver fibrosis. The findings of the present study provide evidence that pyridoxamine is a novel target for the treatment of liver fibrosis.

The Role of the Transsulfuration Pathway in Non-Alcoholic Fatty Liver Disease

The prevalence of non-alcoholic fatty liver disease (NAFLD) is increasing and approximately 25% of the global population may have NAFLD. NAFLD is associated with obesity and metabolic syndrome, but its pathophysiology is complex and only partly understood. The transsulfuration pathway (TSP) is a metabolic pathway regulating homocysteine and cysteine metabolism and is vital in controlling sulfur balance in the organism. Precise control of this pathway is critical for maintenance of optimal cellular function. The TSP is closely linked to other pathways such as the folate and methionine cycles, hydrogen sulfide (H₂S) and glutathione (GSH) production. Impaired activity of the TSP will cause an increase in homocysteine and a decrease in cysteine levels. Homocysteine will also be increased due to impairment of the folate and methionine cycles. The key enzymes of the TSP, cystathionine β-synthase (CBS) and cystathionine γ-lyase (CSE), are highly expressed in the liver and deficient CBS and CSE expression causes hepatic steatosis, inflammation, and fibrosis in animal models. A causative link between the TSP and NAFLD has not been established. However, dysfunctions in the TSP and related pathways, in terms of enzyme expression and the plasma levels of the metabolites (e.g., homocysteine, cystathionine, and cysteine), have been reported in NAFLD and liver cirrhosis in both animal models and humans. Further investigation of the TSP in relation to NAFLD may reveal mechanisms involved in the development and progression of NAFLD.

Vitamin B6 efficacy in the treatment of nonalcoholic fatty liver disease: an open-label, single-arm, single-center trial

Vitamin B6 is an important cofactor in fat metabolism and its deficiency has been correlated with nonalcoholic fatty liver disease. However, no study has investigated the efficacy of vitamin B6 supplementation in these patients. The aim of this open-label, single-arm, single-center study was to examine the therapeutic effect of vitamin B6 in patients with nonalcoholic fatty liver disease. Twenty-two patients with nonalcoholic fatty liver disease received vitamin B6 (90 mg/day) orally for 12 weeks. Clinical parameters were evaluated, and liver fat and fibrosis were quantified before and after treatment using magnetic resonance imaging-based proton density fat fraction and magnetic resonance elastography. Serum alanine aminotransferase levels, the primary endpoint, did not change significantly after vitamin B6 treatment (93.6 ± 46.9 to 93.9 ± 46.6, p = 0.976). On the other hand, magnetic resonance imaging-based proton density fat fraction, a parameter of hepatic lipid accumulation, was significantly reduced (18.7 ± 6.1 to 16.4 ± 6.4, p<0.001) despite no significant changes in body mass index, even in those not taking vitamin E (n = 17, 18.8 ± 6.9 to 16.7 ± 7.3, p = 0.0012). Vitamin B6 administration significantly ameliorated hepatic fat accumulation. As an inexpensive agent with few side effects, vitamin B6 could be a novel therapeutic agent for the treatment of nonalcoholic fatty liver disease.

Vitamin B6 and Diabetes: Relationship and Molecular Mechanisms

Vitamin B6 is a cofactor for approximately 150 reactions that regulate the metabolism of glucose, lipids, amino acids, DNA, and neurotransmitters. In addition, it plays the role of antioxidant by counteracting the formation of reactive oxygen species (ROS) and advanced glycation end-products (AGEs). Epidemiological and experimental studies indicated an evident inverse association between vitamin B6 levels and diabetes, as well as a clear protective effect of vitamin B6 on diabetic complications. Interestingly, by exploring the mechanisms that govern the relationship between this vitamin and diabetes, vitamin B6 can be considered both a cause and effect of diabetes. This review aims to report the main evidence concerning the role of vitamin B6 in diabetes and to examine the underlying molecular and cellular mechanisms. In addition, the relationship between vitamin B6, genome integrity, and diabetes is examined. The protective role of this vitamin against diabetes and cancer is discussed.

Diagnostic Performance of Serum Asialo-α1-acid Glycoprotein for Advanced Liver Fibrosis or Cirrhosis in Patients with Chronic Hepatitis B or Nonalcoholic Fatty Liver Disease

Background/Aims

The utility of asialo-α1-acid glycoprotein (AsAGP) for assessing the fibrotic burden is unknown. This study examined the diagnostic performance of the AsAGP level for advanced liver fibrosis or cirrhosis in patients with chronic hepatitis B (CHB) or nonalcoholic fatty liver disease (NAFLD).

Methods

From July to December 2018, 48 patients with CHB and 75 with NAFLD were recruited prospectively. Transient elastography was used as the reference standard for liver fibrosis, and the cutoff liver stiffness values were defined as 10.0 kilopascal (kPa) for ≥F3 and 12.0 kPa for F4 in CHB patients, and 9.0 kPa for ≥F3 and 11.8 kPa for F4 in NAFLD patients.

Results

To predict stage ≥F3 and F4 fibrosis, the areas under the receiver operating characteristic curves of the AsAGP level in patients with CHB were 0.788 (95% CI 0.647-0.930; p=0.005) and 0.825 (95% CI 0.674-0.976; p=0.004), respectively. The cutoff AsAGP levels in patients with CHB that maximized the sum of the sensitivity and specificity values were 1.31 (sensitivity 100.0%, specificity 52.6%) and 1.55 (sensitivity 75.0%, specificity 80.0%), respectively. In contrast, the AsAGP level was similar regardless of the fibrosis stage in patients with NAFLD (all p>0.05 between the stages).

Conclusions

The AsAGP level showed acceptable diagnostic accuracy in predicting advanced liver fibrosis and cirrhosis in patients with CHB but not in those with NAFLD. Further studies will be needed to validate the diagnostic performance of the AsAGP level in patients with NALFD.

The multifaceted role of vitamin B6 in cancer: Drosophila as a model system to investigate DNA damage

A perturbed uptake of micronutrients, such as minerals and vitamins, impacts on different human diseases, including cancer and neurological disorders. Several data converge towards a crucial role played by many micronutrients in genome integrity maintenance and in the establishment of a correct DNA methylation pattern. Failure in the proper accomplishment of these processes accelerates senescence and increases the risk of developing cancer, by promoting the formation of chromosome aberrations and deregulating the expression of oncogenes. Here, the main recent evidence regarding the impact of some B vitamins on DNA damage and cancer is summarized, providing an integrated and updated analysis, mainly centred on vitamin B₆. In many cases, it is difficult to finely predict the optimal vitamin rate that is able to protect against DNA damage, as this can be influenced by a given individual's genotype. For this purpose, a precious resort is represented by model organisms which allow limitations imposed by more complex systems to be overcome. In this review, we show that Drosophila can be a useful model to deeply understand mechanisms underlying the relationship between vitamin B₆ and genome integrity.

Randomized Clinical Trial: Bergamot Citrus and Wild Cardoon Reduce Liver Steatosis and Body Weight in Non-diabetic Individuals Aged Over 50 Years

Background: Non-alcoholic fatty liver disease is the most common cause of liver-related morbidity and mortality in the world. However, no effective pharmacological treatment for this condition has been found. Purpose: This study evaluated the effect of a nutraceutical containing bioactive components from Bergamot citrus and wild cardoon as a treatment for individuals with fatty liver disease. The primary outcome measure was the change in liver fat content. Methods: A total of 102 patients with liver steatosis were enrolled in a double-blind placebo controlled clinical trial. The intervention group received a nutraceutical containing a Bergamot polyphenol fraction and Cynara Cardunculus extract, 300 mg/day for 12 weeks. The control group received a placebo daily. Liver fat content, by transient elastography, serum transaminases, lipids and glucose were measured at the baseline and the end of the study. Results: We found a greater liver fat content reduction in the participants taking the nutraceutical rather than placebo (-48.2 ± 39 vs. -26.9 ± 43 dB/m, p = 0.02); The percentage CAP score reduction was statistically significant in those with android obesity, overweight/obesity as well as in women. However, after adjustment for weight change, the percentage CAP score reduction was statistically significant only in those over 50 years (44 vs. 78% in placebo and nutraceutical, respectively, p = 0.007). Conclusions: This specific nutraceutical containing bioactive components from Bergamot and wild cardoon reduced the liver fat content during 12 weeks in individuals with liver steatosis over 50 years. If confirmed, this nutraceutical could become the cornerstone treatment of patients affected by liver steatosis. Clinical Trial Registration: www.isrctn.com, identifier ISRCTN12833814.

Vitamin B6 deficiency in new born rats affects hepatic cardiolipin composition and oxidative phosphorylation

Vitamin B6 deficiency during pregnancy translates into a severe vitamin B6 deficiency (plasma levels decreased by 97%) in new-born rats. Further, hallmarks are increased (+89%) concentrations of homocysteine, gross changes in gene methylation and expression, and metabolic alterations including lipid metabolism. This study focuses on determining the effects of vitamin B6-deficiency on cardiolipin composition and oxidative phosphorylation in liver. For this purpose, hepatic cardiolipin composition was analyzed by means of LC/MS/MS, and mitochondrial oxygen consumption was determined by using a Clark-type electrode in a rat model of vitamin B6 deficiency. Liver mitochondria from new-born rats with pre-term vitamin B6 deficiency responded with substantial alterations in cardiolipin composition that include the following changes in the amounts of cardiolipin incorporated fatty acids: increase in C16, decrease in C18, decrease in saturated fatty acid, as well as increase in amount of oxidized cardiolipin species. These changes were accompanied by significantly decreased capacity of oxidative phosphorylation. In conclusion, vitamin B6 deficiency in new born rats induces massive alterations of cardiolipin composition and function of liver mitochondria. These findings support the importance of sufficient periconceptional supply of vitamin B6 to prevent vitamin B6 deficiency.

Impact statement

Vitamin B6 (VitB6) is an active co-enzyme for more than 150 enzymes and is required for a great diversity of biosynthesis and metabolic reactions. There is an increased need for VitB6 during pregnancy and sufficient supply of VitB6 is crucial for the prevention of cleft palate and neural tube defects. We show that liver mitochondria from new-born rats with pre-term VitB6 deficiency respond with substantial alterations in cardiolipin (CL) composition and in the amount of oxidized CL species. These changes are associated with a decrease in the efficiency of oxidative phosphorylation. The results of this study support the significance of sufficient supply of VitB6 during pregnancy (and periconceptional) for diminishing the number of early abortions and minimizing malformation. The established link between VitB6 deficiency, CL composition, and mitochondrial respiration/energy production provides mechanistic insight as to how the VitB6 deficiency translates into the known pathophysiological and clinically relevant conditions.

Association Between Index of Nutritional Quality and Nonalcoholic Fatty Liver Disease: The Role of Vitamin D and B Group

BACKGROUND

Numerous studies have revealed that diet has been considered as an important pathogenic factor for nonalcoholic fatty liver disease (NAFLD). The Index of Nutritional Quality (INQ) is a method of quantitative and qualitative evaluation of single foods and diets, which has special significance in recognizing clinical nutritional problems.

MATERIALS AND METHODS

This study included 295 patients with NAFLD and 704 controls. The dietary intake was assessed through a valid and reliable food frequency questionnaire. INQ was calculated from the questionnaire data and was compared between the 2 groups.

RESULTS

The controls had higher INQ of vitamin D, vitamin E, thiamin, riboflavin, niacin, vitamin B12; biotin, pantothenic acid, magnesium and zinc compared to the patients with NAFLD. After controlling for several covariates, positive associations were observed between NAFLD risk and INQs of riboflavin (OR_riboflavin = 0.49, 95% confidence interval [CI]: 0.28-0.78; OR_biotin = 0.35, 95% CI: 0.18-0.76; OR_pantothenic = 0.28, 95% CI: 0.12-0.64; OR_magnesium = 0.28, 95% CI: 0.11-0.75; OR_zinc = 0.15 95% CI: 0.05-0.42).

CONCLUSIONS

Findings of the present study suggest that subjects who follow a more healthy and nutrient-rich diet, especially in terms of vitamins D, B1, B2, B12, B3 and zinc, are at a lower risk of NAFLD compared to those who consume unhealthy and nutrient-poor diet.

Vitamin B6 improves blood parameters in rats fed a protein-deficient diet and subjected to moderate, long-term exercise

Vitamin B₆ is necessary for many enzymatic pathways (glucose and lipid metabolism, DNA/RNA synthesis, or modulation of gene expression) and affects immune cell function and blood-forming processes. We hypothesised that supplementing a protein-deficient diet with vitamin B₆ may reduce the negative impact of protein malnutrition. Here, we evaluated the effect of moderate, long-term exercise (ninety days) on selected blood parameters in rats fed a normal diet, a protein-deficient diet, or a protein-deficient diet supplemented with vitamin B₆. Selected haematological, immunological, and biochemical parameters were examined. A protein-deficient diet lasting 90 days caused significant reduction in body mass, increased activity of aminotransferases (asparagine and alanine), an increased percentage of innate cells in the blood, and decreased haemoglobin concentration in the blood. Adding vitamin B₆ significantly increased body and muscle mass, decreased liver parameters, and caused normalisation of haemoglobin concentration and the proportion of white blood cells in the blood. These results indicate that vitamin B₆ supplementation significantly improves the health of protein-malnourished rats and paves the way for the development of novel anti-malnutrition therapies.

Weight Gain and Liver Steatosis in Patients with Inflammatory Bowel Diseases

Background and Aim: Most studies focused on the benefits of weight loss on hepatic steatosis and no studies have been specifically designed to assess the role of weight gain on the development of liver steatosis in patients affected by inflammatory bowel diseases. The aim of this study was to analyse the relation between weight change over time and liver steatosis in patients with inflammatory bowel diseases. Methods: We retrospectively evaluated a population of 89 ambulatory patients in clinical remission or affected by mild disease, as determined from disease activity indices, with at least one follow-up visit. Transient elastography was used to quantify liver steatosis. Results: A total of 49 individuals (55%) were overweight/obese at baseline. A significant difference in weight change was found between participants that improved, were stable and worsened, over a mean follow-up of four years. (−1.0 kg ± 4; 2.5 kg ± 6; and 5.4 kg ± 5; respectively, p = 0.009). We found a greater probability of worsening in the hepatic fat content in individuals who gained more than 6% of body weight than in those gaining less than this value (log–rank (Mantel–Cox) χ² test = 9.85; df = 1; p = 0.002). Conclusions: A body weight gain of 6% increases the probability of deterioration in liver steatosis over a period of four years in patients with inflammatory bowel diseases. Weight gain prevention with lifestyle interventions may be the cornerstone treatment of these patients.

Effect of the replacement of dietary vegetable oils with a low dose of extravirgin olive oil in the Mediterranean Diet on cognitive functions in the elderly

BACKGROUND

Numerous studies have investigated the role of the monounsaturated fatty acid and other dietary factors in the prevention of cognitive decline but the short-term effect of a low dose of extravirgin olive oil on cognitive performances in the elderly have not still been investigated. Our aim was to investigate whether the replacement of all vegetable oils with a lower amount of extravirgin olive oil, in the contest of a Mediterranean Diet, would improve cognitive performances, among elderly Italian individuals.

METHODS

180 elderly individuals were randomly assigned to these treatment groups for 1 year: (1) MedDiet plus extravirgin OO, 20-30 g/day; (2) control MedDiet. The cognitive sub-test of ADAScale was used to detect cognitive decline progression over 12 months.

RESULTS

ADAS-cog score variation after 1 year, adjusted for food groups which were different between groups, was - 1.6 ± 0.4 and - 3.0 ± 0.4 in the MedDiet and MedDiet plus extravirgin OO groups, respectively (p = 0.024). Extravirgin OO intake was 30 g ± 12 and 26 g ± 6 in the MedDiet and MedDiet plus extravirgin OO groups, respectively (p = 0.044).

CONCLUSIONS

We demonstrated the higher short-term improvement of cognitive functions scores in individuals of the MedDiet plus low dose of extravirgin olive oil rather than MedDiet alone. Extravirgin olive oil is the best quality oil and may have a neuroprotective effect.