Carotenoids and non-alcoholic fatty liver disease

Association between dietary vitamin A intake from different sources and non-alcoholic fatty liver disease among adults

Non-alcoholic fatty liver disease (NAFLD) has become an urgent public health issue with high global prevalence, but data on NAFLD are inconsistent. The association of total dietary vitamin A intake with the NAFLD risk was not well documented in previous studies. To explore the relationship between dietary vitamin A intake from different sources and NAFLD risk among American adults. Data were collected from the National Health and Nutrition Examination Survey (NHANES) from 2007 to 2014. Logistic regression and restricted cubic spline models were used to estimate the relationship between total dietary vitamin A intake and NAFLD risk. 6,613 adult participants were included. After adjusting potential confounders, the odds ratios (ORs) with 95% confidence intervals (CIs) of NAFLD for the highest quartile intake of total vitamin A, preformed vitamin A, provitamin A carotenoids were respectively 0.86 (0.69-1.06), 0.97 (0.74-1.28), and 0.78 (0.61-0.99), compared to the lowest quartile. Stratifying gender and age, provitamin A carotenoids intake was inversely associated with NAFLD risk in females and participants aged < 45 years. Dose-response analysis indicated a linear negative relationship between provitamin A carotenoids intake and NAFLD risk. Provitamin A carotenoids intake was inversely associated with NAFLD, especially in women and those aged < 45 years among adult American.

Red and golden tomato administration improves fat diet-induced hepatic steatosis in rats by modulating HNF4α, Lepr, and GK expression

Introduction

Nonalcoholic fatty liver disease (NAFLD), characterized by lipid accumulation within hepatocytes exceeding 5% of liver weight, is strongly related to metabolic disorders, obesity, and diabetes and represents a health emergency worldwide. There is no standard therapy available for NAFLD. Lifestyle intervention, including phytonutrient intake, is key in preventing NAFLD development and progression.

Methods

We used a rat model of NAFLD to evaluate the effect of dietary supplementation with red tomato (RT) and golden tomato (GT)-a patented mix of fruit with varying degrees of ripeness and particularly rich in naringenin and chlorogenic acid-after steatosis development. We assessed the effects on body weight, metabolic profile, and hepatic steatosis.

Results and discussion

We found a correlation between the amelioration of all the parameters and the liver gene expression. Our results showed that, together with the reversion of steatosis, the consumption of RT and GT can cause a significant reduction in triglycerides, low-density lipoprotein-cholesterol, fasting glucose, and homeostasis model assessment index. Meanwhile, we observed an increase in high-density lipoprotein-cholesterol according to the amelioration of the general lipidic profile. Regarding hepatic gene expression, we found the upregulation of Gk and Hnf4α involved in metabolic homeostasis, Lepr involved in adipokine signaling, and Il6 and Tnf involved in inflammatory response. Taken together, our results suggest that dietary intake of red and golden tomatoes, as a nutraceutical approach, has potential in preventing and therapeutics of NAFLD.

The Effect of the Saffron Intervention on NAFLD Status and Related Gene Expression in a Rat Model

Background

According to the worldwide increasing prevalence of non-alcoholic fatty liver disease (NAFLD), the present study aimed to investigate the mechanism effects of saffron consumption on preventing NAFLD in a rat model.

Methods

In an experimental study, 12 rats were randomly divided into 2 groups to be evaluated in the prevention phase for 7 weeks. In the prevention phase, the animals were randomly assigned to either fed HFHS + 250 mg/kg saffron (S) or fed with HFHS. Afterward, parts of the liver were excised for histopathologic examination. Plasma concentrations of ALT, AST, GGT, ALP, serum lipids, insulin concentrations, plasma glucose, hs-CRP, and TAC were measured. Moreover, Also, the gene expression of 6 target genes was evaluated, including FAS, ACC1, CPT1 ،PPARα ،DGAT2, and SREBP 1-c at the beginning and end of the study. Also, the differences among groups were evaluated by the Mann-Whitney test for non-normal data and the independent t test for normal data.

Results

The prevention phase groups have a significant elevation in body weight ( P = 0.034) and food intake (P = 0.001) of the HFHS group versus HFHS + 250 mg/kg S group. Also, there was a significant difference between groups 1 and 2 for ALT (P = 0.011) and AST (P = 0.010), and TG (P = 0.040). The HFHS group had higher plasma levels of FBS (P = 0.001), insulin (P = 0.035), HOMA-IR (P = 0.032), and lower TAC (P = 0.041) versus the HFHS+ S group. Also, the difference between HFHS + 250 mg/kg S and HFHS for PPARα gene expression was significant (P = 0.030).

Conclusion

The present study showed that consumption of saffron could prevent developing NAFLD in rats at least partially through modulation in gene expression of PPARα.

Consumption of Spinach and Tomato Modifies Lipid Metabolism, Reducing Hepatic Steatosis in Rats

Non-alcoholic fatty liver disease (NAFLD) is currently a serious and growing clinical problem in developed and developing countries and is considered one of the most frequent chronic liver diseases in the world. The aim of this study was to evaluate the functionality of dietary carotenoids provided by tomato and spinach in the dietary treatment of steatosis. Twenty-two Sprague-Dawley rats with induced steatosis were grouped into three groups and fed standard diet (CD group) and two experimental diets supplemented with 12.75% (LC12.75 group) and 25.5% (HC25.5 group) of a mixture of spinach and tomato powder. Rats fed carotenoid-rich feeds showed an improvement in the plasma biomarkers of steatosis, with lower levels of glucose, total cholesterol, VLDL, TG, proteins, ALT and AST. Likewise, a decrease in oxidative stress was observed, with a significant reduction of malondialdehyde (MDA) in plasma (up to 54%), liver (up to 51.42%) and urine (up to 78.89%) (p < 0.05) and an increase in plasma antioxidant capacity (ORAC) (up to 73.41%) (p < 0.05). Furthermore, carotenoid-rich diets led to an accumulation of carotenoids in the liver and were inversely correlated with the content of total cholesterol and hepatic triglycerides, increasing the concentrations of MUFA and PUFA (up to 32.6% and 48%, respectively) (p < 0.05). The accumulation of carotenoids in the liver caused the modulation of genes involved in lipid metabolism, and we particularly observed an overexpression of ACOX1, APOA1 and NRIH2 (LXR) and the synthesis of the proteins. This study suggests that dietary carotenoids from spinach and tomato aid in the dietary management of steatosis by reversing steatosis biomarkers.

Effects of Cabbage-Apple Juice Fermented by Lactobacillus plantarum EM on Lipid Profile Improvement and Obesity Amelioration in Rats

This study aimed to investigate the potential of cabbage-apple juice, fermented by Lactobacillus plantarum EM isolated from kimchi, to protect against obesity and dyslipidemia that are induced by a high-fat diet in a rat model. Male rats were fed a modified AIN-93M high-fat diet (HFD), the same diet supplemented with non-fermented cabbage-apple juice, or the same diet supplemented with fermented cabbage-apple juice for eight weeks. In the HFD-fermented cabbage- apple juice administered groups the following parameters decreased: body weight, liver and white fat pad weights, serum triglyceride (TG), total cholesterol (TC), LDL-cholesterol, insulin, glucose and leptin levels, TG levels, while HDL-C and adiponectin levels in serum increased as compared with the HFD group. The HFD-fed rats that were supplemented with fermented cabbage-apple juice exhibited significantly lower fatty acid synthase (FAS), acetyl-CoA carboxylase (ACC), and malic enzyme gene expression levels when compared to the exclusively HFD-fed rats. The anti-obesity and hypolipidemic effects were marginally greater in the fermented juice administered group than in the non-fermented juice administered group. These results suggest that cabbage-apple juice-especially fermented cabbage-apple juice-might have beneficial effects on lipid metabolism dysfunction and obesity-related abnormalities. However, further studies are necessary for analyzing the biochemical regulatory mechanisms of fermented juice for obesity amelioration and lipid metabolic homeostasis.

Carotenoids of Capsicum Fruits: Pigment Profile and Health-Promoting Functional Attributes

Pepper of the Capsicum species is a common ingredient in various food preparations by different cultures worldwide. The Capsicum is recognised by its five main domesticated species, namely Capsicum annuum, C. baccatum, C. chinense, C. frutescens and C. pubescens. The genetic diversity in Capsicum offers fruits in wide ranges of morphology and carotenoid profile. Carotenoids enhance the value of pepper from a nutritional standpoint, despite being commonly prized for the pharmacologically active pungent capsaicinoids. Carotenoids of pepper comprise mainly of the unique, powerful and highly stable capsanthin and capsoroubin, together with β-carotene, β-cryptoxanthin, lutein, zeaxanthin, antheraxanthin and violaxanthin. These carotenoids are present at diverse profile and varying levels, biosynthetically connected to the fruit maturity stages. This review describes the health-promoting functional attributes of the carotenoids that are mainly associated with their excellent role as lipophilic antioxidants. Capsicum as a great source of carotenoids is discussed in the aspects of main domesticated species, biosynthesis, pigment profile, antioxidant activity and safety. Findings from a number of in vitro, in vivo and clinical studies provided appreciable evidence on the protective effects of pepper’s carotenoids against degenerative diseases. Hence, pepper with its functional carotenoids might be recommended in health-promoting and disease preventing strategies.

Lycopene Modulates Pathophysiological Processes of Non-Alcoholic Fatty Liver Disease in Obese Rats

Background: The higher consumption of fat and sugar are associated with obesity development and its related diseases such as non-alcoholic fatty liver disease (NAFLD). Lycopene is an antioxidant whose protective potential on fatty liver degeneration has been investigated. The aim of this study was to present the therapeutic effects of lycopene on NAFLD related to the obesity induced by a hypercaloric diet. Methods: Wistar rats were distributed in two groups: Control (Co, n = 12) and hypercaloric (Ob, n = 12). After 20 weeks, the animals were redistributed into the control group (Co, n = 6), control group supplemented with lycopene (Co+Ly, n = 6), obese group (Ob, n = 6), and obese group supplemented with lycopene (Ob+Ly, n = 6). Ob groups also received water + sucrose (25%). Animals received lycopene solution (10 mg/kg/day) or vehicle (corn oil) via gavage for 10 weeks. Results: Animals which consumed the hypercaloric diet had higher adiposity index, increased fasting blood glucose, hepatic and blood triglycerides, and also presented in the liver macro and microvesicular steatosis, besides elevated levels of tumor necrosis factor-α (TNF-α). Lycopene has shown therapeutic effects on blood and hepatic lipids, increased high-density lipoprotein cholesterol (HDL), mitigated TNF-α, and malondialdehyde (MDA) and further improved the hepatic antioxidant capacity. Conclusion: Lycopene shows therapeutic potential to NAFLD.

Dual Role of Reactive Oxygen Species in Muscle Function: Can Antioxidant Dietary Supplements Counteract Age-Related Sarcopenia?

Sarcopenia is characterized by the progressive loss of skeletal muscle mass and strength. In older people, malnutrition and physical inactivity are often associated with sarcopenia, and, therefore, dietary interventions and exercise must be considered to prevent, delay, or treat it. Among the pathophysiological mechanisms leading to sarcopenia, a key role is played by an increase in reactive oxygen and nitrogen species (ROS/RNS) levels and a decrease in enzymatic antioxidant protection leading to oxidative stress. Many studies have evaluated, in addition to the effects of exercise, the effects of antioxidant dietary supplements in limiting age-related muscle mass and performance, but the data which have been reported are conflicting. In skeletal muscle, ROS/RNS have a dual function: at low levels they increase muscle force and adaptation to exercise, while at high levels they lead to a decline of muscle performance. Controversial results obtained with antioxidant supplementation in older persons could in part reflect the lack of univocal effects of ROS on muscle mass and function. The purpose of this review is to examine the molecular mechanisms underlying the dual effects of ROS in skeletal muscle function and the analysis of literature data on dietary antioxidant supplementation associated with exercise in normal and sarcopenic subjects.

Gut Microbiota-Derived Components and Metabolites in the Progression of Non-Alcoholic Fatty Liver Disease (NAFLD)

Human gut microbiota has been increasingly recognized as a pivotal determinant of non-alcoholic fatty liver disease (NAFLD). Apart from the changes in the composition of gut microbiota, the components and metabolites derived from intestinal microbiota have emerged as key factors in modulating the pathological process of NAFLD. Compelling evidences have revealed that gut microbiota generates a variety of bioactive substances that interact with the host liver cells through the portal vein. These substances include the components derived from bacteria such as lipopolysaccharides, peptidoglycan, DNA, and extracellular vesicles, as well as the metabolites ranging from short-chain fatty acids, indole and its derivatives, trimethylamine, secondary bile acids, to carotenoids and phenolic compounds. The mechanisms underlying the hepatic responses to the bioactive substances from gut bacteria have been associated with the regulation of glycolipid metabolism, immune signaling response, and redox homeostasis. Illuminating the interplay between the unique factors produced from gut microbiome and the liver will provide a novel therapeutical target for NAFLD. The current review highlights the recent advances on the mechanisms by which the key ingredients and metabolites from gut microbiota modulate the development and progression of NAFLD.

Nutritional Importance of Carotenoids and Their Effect on Liver Health: A Review

The consumption of carotenoids has beneficial effects on health, reducing the risk of certain forms of cancer, cardiovascular diseases, and macular degeneration, among others. The mechanism of action of carotenoids has not been clearly identified; however, it has been associated with the antioxidant capacity of carotenoids, which acts against reactive oxygen species and inactivating free radicals, although it has also been shown that carotenoids modulate gene expression. Dietary carotenoids are absorbed and accumulated in the liver and other organs, where they exert their beneficial effects. In recent years, it has been described that the intake of carotenoids can significantly reduce the risk of suffering from liver diseases, such as non-alcoholic fatty liver disease (NAFLD). This disease is characterized by an imbalance in lipid metabolism producing the accumulation of fat in the hepatocyte, leading to lipoperoxidation, followed by oxidative stress and inflammation. In the first phases, the main treatment of NAFLD is to change the lifestyle, including dietary habits. In this sense, carotenoids have been shown to have a hepatoprotective effect due to their ability to reduce oxidative stress and regulate the lipid metabolism of hepatocytes by modulating certain genes. The objective of this review was to provide a description of the effects of dietary carotenoids from fruits and vegetables on liver health.

Health Benefits of Carotenoids: A Role of Carotenoids in the Prevention of Non-Alcoholic Fatty Liver Disease

Non-alcoholic fatty liver disease (NAFLD) is one of the most common chronic liver diseases with a prevalence of ~25% worldwide. NAFLD includes simple hepatic steatosis, non-alcoholic steatohepatitis, fibrosis, and cirrhosis, which can further progress to hepatocellular carcinoma. Therefore, effective strategies for the prevention of NAFLD are needed. The pathogenesis of NAFLD is complicated due to diverse injury insults, such as fat accumulation, oxidative stress, inflammation, lipotoxicity, and apoptosis, which may act synergistically. Studies have shown that carotenoids, a natural group of isoprenoid pigments, prevent the development of NAFLD by exerting antioxidant, lipid-lowering, anti-inflammatory, anti-fibrotic, and insulin-sensitizing properties. This review summarizes the protective action of carotenoids, with primary focuses on astaxanthin, lycopene, β-carotene, β-cryptoxanthin, lutein, fucoxanthin, and crocetin, against the development and progression of NAFLD.

Ameliorative Effect of Spinach on Non-Alcoholic Fatty Liver Disease Induced in Rats by a High-Fat Diet

The purpose of this work was to evaluate the effect of dietary carotenoids from spinach on the inflammation and oxidative stress biomarkers, liver lipid profile, and liver transcriptomic and metabolomics profiles in Sprague–Dawley rats with steatosis induced by a high-fat diet. Two concentrations of spinach powder (2.5 and 5%) were used in two types of diet: high-fat (H) and standard (N). Although rats fed diet H showed an accumulation of fat in hepatocytes, they did not show differences in the values of adiponectin, tumor necrosis factor alpha (TNF-α), and oxygen radical absorption (ORAC) in plasma or of isoprostanes in urine compared with animals fed diet N. The consumption of spinach and the accumulation of α and β carotenes and lutein in the liver was inversely correlated with serum total cholesterol and glucose and the content of hepatic cholesterol, increasing monounsaturated fatty acids (MUFA), polyunsaturated fatty acids (PUFA) and reducing cholesterol in the livers of rats fed diet H and spinach. In addition, changes in the expression of genes related to the fatty liver condition occurred, and the expression of genes involved in the metabolism of fatty acids and cholesterol increased, mainly through the overexpression of peroxisome proliferator activated receptors (PPARs). Related to liver metabolites, animals fed with diet H showed hypoaminoacidemia, mainly for the glucogenic aminoacids. Although no changes were observed in inflammation and oxidative stress biomarkers, the consumption of spinach modulated the lipid metabolism in liver, which must be taken into consideration during the dietary treatment of steatosis.

Estimation and Validation of Dietary Nitrate and Nitrite Intake in Iranian Population

BACKGROUND

The aim of this study was calibration of a nitrate (NO₃)/nitrite (NO₂) database for estimated its dietary intakes.

METHODS

Overall, 250 healthy Tehranian adults were assessed in 2015 for dietary intakes of NO₃ and NO₂ and its serum and urine concentration. Food composition values for NO₃ and NO₂ were derived from a recent survey conducted on frequently consumed food items among Iranians. The correlation of dietary intakes of NO₃/NO₂ and its urinary and serum values was evaluated.

RESULTS

Mean (±SD) intakes of dietary NO₃ and NO₂ were 505±160 and 7.7±2.2 mg/d, respectively. The correlation coefficient of intake and urinary NO₃ was 0.83 (95% CI=0.56-0.91) and 0.57 (95% CI=0.49-0.67) in men and women, respectively. A moderate agreement was also observed between NO₂ intake and its urinary levels (r=0.27, 95% CI=0.13-0.37, and 0.29, 95% CI=0.17-0.41, in men and women, respectively).

CONCLUSION

Using a national database of NO₃ and NO₂ content of food items along with a valid food frequency questionnaire could provide a valid estimation of dietary intakes of NO₃ in the target population.

Tomato Juice Supplementation Influences the Gene Expression Related to Steatosis in Rats

The objective of this work was to identify the effect of tomato juice on the expression of genes and levels of metabolites related to steatosis in rats. Male Sprague Dawley rats (8 weeks-old) were grouped (6 rats/group) in four experimental groups: NA (normal diet and water), NL (normal diet and tomato juice), HA (high-fat diet and water), and HL (high-fat diet and tomato juice). After an intervention period of 5 weeks, rats were sacrificed and biochemical parameters, biomarkers of oxidative stress, liver metabolites, and gene expression were determined. Although the H diet provoked dislipemia related to steatosis, no changes in isoprostanes or liver malondialdehyde (MDA) were observed. Changes in the gene expression of the HA group were produced by the high consumption of fat, whereas the consumption of tomato juice had different effects, depending on the diet. In the NL group, the genes involved in β-oxidation were upregulated, and in groups NL and HL upregulation of CD36 and downregulation of APOB and LPL were observed. In addition, in the HL group the accumulation of lycopene upregulated the genes FXR and HNF4A, which have been suggested as preventive factors in relation to steatosis. Regarding the metabolomics study, intake of tomato juice stimulated the biosynthesis of glutathione and amino acids of the transulfurization pathway, increasing the levels of metabolites related to the antioxidant response.

Isobavachalcone from Angelica keiskei Inhibits Adipogenesis and Prevents Lipid Accumulation

We isolated isobavachalcone (IBC) from Angelica keiskei (AK) as an anti-obesity component. IBC dose-dependently inhibited 3T3-L1 adipocyte differentiation by down-regulating adipogenic factors. At the mitotic clonal expansion stage (MCE), IBC caused cell cycle arrest in G0/G1 with decreased expression of cell cycle-regulating proteins. IBC also inhibited autophagic flux by inducing intracellular accumulation of LC3B and SQSTM1/p62 proteins while decreasing expression levels of regulating factors for autophagy initiation. In parallel with the inhibition of adipocyte differentiation, IBC decreased intrahepatic fat deposits and rescued the liver steatosis in high fat cholesterol diet-fed zebrafish. In this study, we found that IBC isolated from AK suppresses mitotic clonal expansion and autophagy flux of adipocytes and also shows anti-obesity activity in a high cholesterol-diet zebrafish model by decreasing intrahepatic fat deposits. These results suggest that IBC could be a leading pharmacological compound for the development of anti-obesity drugs.

Higher serum carotenoids associated with improvement of non-alcoholic fatty liver disease in adults: a prospective study

PURPOSE

Previous studies have suggested that serum carotenoids might be inversely associated with non-alcoholic fatty liver disease (NAFLD), but little data came from longitudinal studies. We prospectively examined the associations between serum-carotenoid levels and NAFLD severity and the intermediary effects of retinol-binding protein 4 (RBP4), HOMA insulin-resistance index (HOMA-IR), body mass index (BMI), and serum triglycerides in middle-aged and elderly Chinese adults.

METHODS

This prospective study included 3336 Chinese adults (40-75 years). We assessed serum concentrations of carotenoids at baseline and determined serum RBP4, triglycerides, and HOMA-IR levels at year 3. Abdominal ultrasonography was conducted to assess the presence and degree of NAFLD at years 3 and 6.

RESULTS

The 2687 subjects who completed both NAFLD tests were classified into stable, improved and progressed groups according to changes in the degree of NAFLD between two visits. Analyses of covariance showed that ln-transformed serum concentrations of α-carotene, β-cryptoxanthin, β-carotene, lycopene, lutein/zeaxanthin, and total carotenoids were positively associated with NAFLD improvement (all p-trend < 0.05). After multivariable adjustment, mean differences in serum carotenoids were higher by 29.6% (β-carotene), 18.2% (α-carotene), 15.6% (β-cryptoxanthin), 11.5% (lycopene), 8.9% (lutein/zeaxanthin), and 16.6% (total carotenoids) in the improved vs. progressed subjects. Path analyses indicated the carotenoid-NAFLD association was mediated by lowering serum RBP4, triglycerides, HOMA-IR, and BMI, which were positively associated with the prevalence and progression of NAFLD.

CONCLUSIONS

In middle-aged and elderly adults, higher serum-carotenoid concentrations were favorably associated with NAFLD improvement, mediated by reducing serum RBP4, triglycerides, HOMA-IR, and BMI.

TRIAL REGISTRATIONS

This study has been registered at http://www.clinicaltrials.gov as NCT03179657.

Total antioxidant capacity of the diet modulates the association between habitual nitrate intake and cardiovascular events: A longitudinal follow-up in Tehran Lipid and Glucose Study

Background

Considering the lack of data on the association between habitual dietary intakes of nitrate (NO₃⁻) and nitrite (NO₂⁻) and cardiovascular events, we assessed possible effects of dietary NO₃⁻ and NO₂⁻, in the context of total antioxidant capacity (TAC) of the diet, with the risk of cardiovascular (CVD) outcomes.

Methods

Adult men and women without CVD (n = 2369) were recruited from the Tehran Lipid and Glucose Study and were followed for a mean of 6.7 years. Dietary NO₃⁻ and NO₂⁻ intakes, as well as dietary TAC and nitric oxide (NO) index were assessed at baseline (2006–2008). Multivariable-adjusted Cox proportional hazards regression models were used to estimate risk of CVD above and below median of dietary intakes of NO₃⁻/NO₂⁻ and dietary TAC and NO index. Due to a significant interaction between NO₃⁻/NO₂⁻ intake and TAC, stratified analyses were done for < and ≥ median dietary TAC.

Results

Daily mean (SD) dietary NO₃⁻ and NO₂⁻ intakes were 460 (195) and 9.5 (3.9) mg; mean (SD) dietary TAC and NO index was 1406 (740) and 338 (197) μmol trolox equivalent (TE)/100 g. In subjects with lower dietary TAC, higher intake of NO₃⁻ (≥ 430 mg/d) was accompanied with an increased risk of CVD (HR = 3.28, 95% CI = 1.54–6.99). There were no significant associations between dietary intakes of NO₂⁻, TAC of the diet and NO index with the occurrence of CVD events during the study follow-up.

Conclusion

High habitual intake of NO₃⁻, in the context of low TAC of the food, may be associated with the risk of CVD outcomes.

Lobster processing by-products as valuable bioresource of marine functional ingredients, nutraceuticals, and pharmaceuticals

The worldwide annual production of lobster was 165,367 tons valued over $3.32 billion in 2004, but this figure rose up to 304,000 tons in 2012. Over half the volume of the worldwide lobster production has been processed to meet the rising global demand in diversified lobster products. Lobster processing generates a large amount of by-products (heads, shells, livers, and eggs) which account for 50-70% of the starting material. Continued production of these lobster processing by-products (LPBs) without corresponding process development for efficient utilization has led to disposal issues associated with costs and pollutions. This review presents the promising opportunities to maximize the utilization of LPBs by economic recovery of their valuable components to produce high value-added products. More than 50,000 tons of LPBs are globally generated, which costs lobster processing companies upward of about $7.5 million/year for disposal. This not only presents financial and environmental burdens to the lobster processors but also wastes a valuable bioresource. LPBs are rich in a range of high-value compounds such as proteins, chitin, lipids, minerals, and pigments. Extracts recovered from LPBs have been demonstrated to possess several functionalities and bioactivities, which are useful for numerous applications in water treatment, agriculture, food, nutraceutical, pharmaceutical products, and biomedicine. Although LPBs have been studied for recovery of valuable components, utilization of these materials for the large-scale production is still very limited. Extraction of lobster components using microwave, ultrasonic, and supercritical fluid extraction were found to be promising techniques that could be used for large-scale production. LPBs are rich in high-value compounds that are currently being underutilized. These compounds can be extracted for being used as functional ingredients, nutraceuticals, and pharmaceuticals in a wide range of commercial applications. The efficient utilization of LPBs would not only generate significant economic benefits but also reduce the problems of waste management associated with the lobster industry. This comprehensive review highlights the availability of the global LPBs, the key components in LPBs and their current applications, the limitations to the extraction techniques used, and the suggested emerging techniques which may be promising on an industrial scale for the maximized utilization of LPBs. Graphical abstractLobster processing by-product as bioresource of several functional and bioactive compounds used in various value-added products.

Antioxidant dietary approach in treatment of fatty liver: New insights and updates

Non-alcoholic fatty liver disease (NAFLD) is a common clinicopathological condition, encompassing a range of conditions caused by lipid deposition within liver cells. To date, no approved drugs are available for the treatment of NAFLD, despite the fact that it represents a serious and growing clinical problem in the Western world. Identification of the molecular mechanisms leading to NAFLD-related fat accumulation, mitochondrial dysfunction and oxidative balance impairment facilitates the development of specific interventions aimed at preventing the progression of hepatic steatosis. In this review, we focus our attention on the role of dysfunctions in mitochondrial bioenergetics in the pathogenesis of fatty liver. Major data from the literature about the mitochondrial targeting of some antioxidant molecules as a potential treatment for hepatic steatosis are described and critically analysed. There is ample evidence of the positive effects of several classes of antioxidants, such as polyphenols (i.e., resveratrol, quercetin, coumestrol, anthocyanins, epigallocatechin gallate and curcumin), carotenoids (i.e., lycopene, astaxanthin and fucoxanthin) and glucosinolates (i.e., glucoraphanin, sulforaphane, sinigrin and allyl-isothiocyanate), on the reversion of fatty liver. Although the mechanism of action is not yet fully elucidated, in some cases an indirect interaction with mitochondrial metabolism is expected. We believe that such knowledge will eventually translate into the development of novel therapeutic approaches for fatty liver.

Nonalcoholic Fatty Liver Disease and Insulin Resistance: New Insights and Potential New Treatments

Nonalcoholic fatty liver disease (NAFLD) is one of the most common chronic liver disorders worldwide. It is associated with clinical states such as obesity, insulin resistance, and type 2 diabetes, and covers a wide range of liver changes, ranging from simple steatosis to non-alcoholic steatohepatitis (NASH), liver cirrhosis, and hepatocellular carcinoma. Metabolic disorders, such as lipid accumulation, insulin resistance, and inflammation, have been implicated in the pathogenesis of NAFLD, but the underlying mechanisms, including those that drive disease progression, are not fully understood. Both innate and recruited immune cells mediate the development of insulin resistance and NASH. Therefore, modifying the polarization of resident and recruited macrophage/Kupffer cells is expected to lead to new therapeutic strategies in NAFLD. Oxidative stress is also pivotal for the progression of NASH, which has generated interest in carotenoids as potent micronutrient antioxidants in the treatment of NAFLD. In addition to their antioxidative function, carotenoids regulate macrophage/Kupffer cell polarization and thereby prevent NASH progression. In this review, we summarize the molecular mechanisms involved in the pathogenesis of NAFLD, including macrophage/Kupffer cell polarization, and disturbed hepatic function in NAFLD. We also discuss dietary antioxidants, such as β-cryptoxanthin and astaxanthin, that may be effective in the prevention or treatment of NAFLD.

Association between Dietary Intakes of Nitrate and Nitrite and the Risk of Hypertension and Chronic Kidney Disease: Tehran Lipid and Glucose Study

Background and Aim: The association of habitual intakes of dietary nitrate (NO₃⁻) and nitrite (NO₂⁻) with blood pressure and renal function is not clear. Here, we investigated a potential effect of dietary NO₃⁻ and NO₂⁻ on the occurrence of hypertension (HTN) and chronic kidney disease (CKD). Methods: A total of 2799 Iranian adults aged ≥20 years, participating in the Tehran Lipid and Glucose Study (TLGS), were included and followed for a median of 5.8 years. Dietary intakes of NO₃⁻ and NO₂⁻ were estimated using a semi-quantitative food frequency questionnaire. Demographics, anthropometrics, blood pressure and biochemical variables were evaluated at baseline and during follow-up examinations. To identify the odds ratio (OR) and 95% confidence interval (CI) of HTN and CKD across tertile categories of residual energy-adjusted NO₃⁻ and NO₂⁻ intakes, multivariate logistic regression models were used. Results: Dietary intake of NO₃⁻ had no significant association with the risk of HTN or CKD. Compared to the lowest tertile category (median intake < 6.04 mg/day), the highest intake (median intake ≥ 12.7 mg/day) of dietary NO₂⁻ was accompanied with a significant reduced risk of HTN, in the fully adjusted model (OR = 0.58, 95% CI = 0.33–0.98; p for trend = 0.054). The highest compared to the lowest tertile of dietary NO₂⁻ was also accompanied with a reduced risk of CKD (OR = 0.50, 95% CI = 0.24–0.89, p for trend = 0.07). Conclusion: Our findings indicated that higher intakes of NO₂⁻ might be an independent dietary protective factor against the development of HTN and CKD, which are major risk factors for adverse cardiovascular events.

The Potential of Non-Provitamin A Carotenoids for the Prevention and Treatment of Non-Alcoholic Fatty Liver Disease

Non-alcoholic fatty liver disease (NAFLD) is an obesity-associated spectrum of comorbidities defined by the presence of metabolic dysfunction, oxidative stress, inflammation, and fibrosis in the liver. If left untreated, NAFLD can progress to cirrhosis, liver failure, or hepatocellular carcinoma. NAFLD is recognized as the most common liver disease in the United States, affecting around 30% of the population. Identification of dietary components capable of reducing or preventing NAFLD is therefore essential to battle this condition. Dietary carotenoids including astaxanthin, lycopene, lutein, and zeaxanthin have been demonstrated to be potent antioxidants as well as to exhibit anti-inflammatory effects. Many studies report the protective effect(s) of these carotenoids against different conditions such as atherosclerosis, diabetic complications, age-related macular degeneration, and liver diseases. In this review, we will focus on the effects of these carotenoids in the prevention or reduction of NAFLD as seen in epidemiological observations and clinical trials, as well as the suggested mechanism of action derived from animal and cell studies.

A Prospective Study of Different Types of Dietary Fiber and Risk of Cardiovascular Disease: Tehran Lipid and Glucose Study

Background and aim: This study was designed to examine the hypothesis that dietary of intake different types of fiber could modify the risk of cardiovascular disease (CVD) in a large prospective cohort among Iranian adults. Methods: In 2006–2008, we used a validated food frequency questionnaire to assess dietary fiber intake among 2295 health professionals with no previous history of heart disease. Subjects were subsequently followed until 2012 for incidence of CVD events. Multivariate Cox proportional hazard regression models, adjusted for potential confounders were used to estimate the risk of CVD across tertiles of total dietary fiber and different types of fiber. Linear regression models were also used to indicate the association of dietary fiber intakes with changes of cardiovascular risk factors during the follow-up. Results: Mean age of participants (42.8% men) was 38.2 ± 13.4, at baseline. Mean (SD) dietary intake of total fiber was 23.4 (8.9) g/day. After adjustment for cardiovascular risk score and dietary confounders, a significant inverse association was observed between intakes of total, soluble and insoluble dietary fiber and CVD risk, in the highest compared to the lowest tertiles (HR = 0.39, 95% CI = 0.18–0.83, HR = 0.19, 95% CI = 0.09–0.41, and HR = 0.31, 95% CI = 0.14–0.69, respectively). Inverse relations were observed between risk of CVD and dietary fiber from legumes, fruits and vegetables; however, dietary fiber intake from grain and nut sources was not related to risk of CVD. Conclusion: Our findings confirmed that higher intakes of dietary fiber from different sources is associated with CVD events and modify its major risk-related factors.

Divergent pathway of lipid profile components for cardiovascular disease and mortality events: Results of over a decade follow-up among Iranian population

BACKGROUND

Data regarding the impact of different lipid measures on cardiovascular diseases (CVD) and mortality events is not consistent. We aimed to evaluate the relationship between different lipid parameters and incident CVD and mortality events in an Iranian population over a median follow-up of 11.9 years.

METHODS

The study was conducted on 2532 men and 2986 women aged ≥ 40 years. Multivariate adjusted hazard ratios (HRs), using age as time scale, were calculated for every 1 standard deviation (SD) increase in total cholesterol (TC), logarithm-transformed triglycerides (ln-TGs), low density lipoprotein-cholesterol (LDL-C), high density lipoprotein-cholesterol (HDL-C), non-HDL-C, TC/HDL-C and ln-TGs/HDL-C. Covariates included gender (female as reference), body mass index, education status, low physical activity, smoking, blood pressure status (normotension, prehypertension and hypertension), glucose tolerance status (normal glucose tolerance, prediabetes and diabetes) and lipid lowering drugs. The same analyses were also repeated for tertiles of all lipid measures. Considering the absence of interaction between gender and lipid parameters, we used a sex-adjusted analysis. For analyses of mortality events, prevalent CVD was adjusted as well (All p for interactions > 0.1).

RESULTS

A total of 789 new CVD events, 279 cardiovascular (CV) and 270 non-CV deaths occurred. In multivariate analysis, all lipid measures except HDL-C showed significant risk for new CVD events with HRs ranged from 1.14 to 1.27 for ln-TGs/HDL-C and LDL-C, respectively (all p-values ≤ 0.001). Considering CV mortality, there were significant positive associations between TC, LDL-C, non-HDL-C, TC/HDL-C and CV mortality events in sex-adjusted analysis; however after multivariate analysis, these associations attenuated and reached to null. Applying lipid measures as categorical variables, only TC displayed a positive association with CV mortality in multivariate analysis [TC ≥ 6.14 mmol/L: HR 1.43 (1.04-1.98)]. In multivariate analysis, there were negative significant associations between all lipid measures except HDL-C and non-CV mortality; every 1-SD increase in TC, LDL-C, non-HDL-C, ln-TGs ,TC/HDL-C and ln-TGs/HDL-C was associated with 24, 25, 27, 19, 23 and 17 % decreased risk in non-CV mortality (all p-values ≤ 0.01).

CONCLUSIONS

These findings indicate divergent associations of TC, LDL-C, non-HDL-C, TC/HDL-C, TGs and TGs/HDL-C with CVD vs non-CV mortality, demonstrating a higher risk for the former and lower risk for the latter.

Novel Action of Carotenoids on Non-Alcoholic Fatty Liver Disease: Macrophage Polarization and Liver Homeostasis

Non-alcoholic fatty liver disease (NAFLD) is the most common chronic liver disease. It is characterized by a wide spectrum of hepatic changes, which may progress to non-alcoholic steatohepatitis (NASH) and cirrhosis. NAFLD is considered a hepatic manifestation of metabolic syndrome; however, mechanisms underlying the onset and progression of NAFLD are still unclear. Resident and recruited macrophages are key players in the homeostatic function of the liver and in the progression of NAFLD to NASH. Progress has been made in understanding the molecular mechanisms underlying the polarized activation of macrophages. New NAFLD therapies will likely involve modification of macrophage polarization by restraining M1 activation or driving M2 activation. Carotenoids are potent antioxidants and anti-inflammatory micronutrients that have been used to prevent and treat NAFLD. In addition to their antioxidative action, carotenoids can regulate macrophage polarization and thereby halt the progression of NASH. In this review, we summarize the molecular mechanisms of macrophage polarization and the function of liver macrophages/Kupffer cells in NAFLD. From our review, we propose that dietary carotenoids, such as β-cryptoxanthin and astaxanthin, be used to prevent or treat NAFLD through the regulation of macrophage polarization and liver homeostasis.

Dietary L-arginine intake and the incidence of coronary heart disease: Tehran lipid and glucose study

Background

We investigated the association of regular dietary intake of L-arginine and both the incidence of coronary heart disease (CHD) and changes of blood pressure.

Methods

Eligible adults (n = 2284) who participated in the Tehran Lipid and Glucose Study were followed for a mean of 4.7 years. Dietary intake of L-arginine was assessed at baseline (2006–2008); biochemical variables were evaluated at baseline and the follow-up examination. Multivariate Cox proportional hazard regression models adjusted for potential confounders were used to estimate the risk of CHD across tertiles of L-arginine intake. Linear regression models were also used to indicate the association of L-arginine intake with changes of serum lipids and blood pressure during the follow-up.

Results

Mean age of participants (42.8 % men) was 38.2 ± 13.4, at baseline. During a mean 4.7 ± 1.4 y of follow-up, 57 participants experienced CHD events. A significant negative association was observed between plant-derived L-arginine intake and changes of both systolic and diastolic blood pressure, whereas animal-derived L-arginine intake was related to increased levels of diastolic blood pressure (P < 0.01). Participants in the 2^nd tertile (1.45–1.78 g/d) had a significantly increased risk of CHD events compared to the participants in the 1^st tertile (<1.45 g/d) (HR = 1.90, 95 % CI = 1.03–3.58). The risk of CHD had a decreasing trend across increasing plant-derived L-arginine intake (HR = 1.0, HR = 0.91, 95 % CI = 0.51–1.62, HR = 0.72, 95 % CI = 0.39–1.32, P for trend = 0.03).

Conclusion

Higher intake of plant derived L-arginine may have a protective effect whereas animal-derived L-arginine may be a risk factor for development of hypertension and CHD events.

Thymoquinone alleviates nonalcoholic fatty liver disease in rats via suppression of oxidative stress, inflammation, apoptosis

Nonalcoholic steatohepatitis (NAFLD) is a progressive form of liver disease that leads to advanced fibrosis. The present study was designed to assess the hepatoprotective effect of thymoquinone (TQ) on liver functions, insulin resistance, and PPAR-γ expression in NAFLD. Rats were divided into two main groups: one fed with normal rat chow diet and the other with high-fat high-cholesterol diet group for 6 weeks. Every group was subdivided into three subgroups (n = 8): treated with saline, low dose TQ (10 mg/kg), high dose TQ (20 mg/kg). High fat high cholesterol diet caused marked liver damage as noted in histopathology and significant increase in liver index, liver enzymes. There was significant increase in the insulin resistance, serum cholesterol, triglyceride, PPAR-γ gene overexpression with significant decrease in HDL. Additionally, oxidative stress increased by measuring MDA associated with significant decrease in serum total antioxidant capacity. As markers of inflammation, hepatic TNF-α was significantly increased with decrease in IL10. Further, there was increase in BAX protein with decrease in Bcl as compared to control group. This model of 6 weeks high-fat high-cholesterol diet showed minimal fibrosis as noticed by increase MMP2 and Masson trichrome satin. Co-treatment with TQ improved all previous parameters. High dose was more effective, although mostly non-statistically significant. TQ may have a promising agent to improve hepatic steatosis, oxidative stress; inflammatory, apoptotic status, fibrosis and so prevent liver damage in patients with NAFLD. Although PPAR-γ was significantly under-expressed by TQ, insulin resistance was improved significantly suggesting a role of liver damage.