New insights into apolipoprotein A5 in controlling lipoprotein metabolism in obesity and the metabolic syndrome patients

Stratification and prognostic evaluation of breast cancer subtypes defined by obesity-associated genes

OBJECTIVE

Breast cancer was the most common type of cancer among women worldwide, significantly impacting their quality of life and survival rates. And obesity has been widely accepted as an important risk factor for breast cancer. However, the specific mechanisms by which obesity affects breast cancer were still unclear. Therefore, studying the impact mechanisms of obesity as a risk factor for breast cancer was of utmost importance.

METHODS

This study was based on TCGA breast cancer RNA transcriptomic data and the GeneCard obesity gene set. Through single and multiple factor Cox analysis and LASSO coefficient screening, seven hub genes were identified. The independent mechanisms of these seven hub genes were evaluated from various aspects, including survival data, genetic mutation data, single-cell sequencing data, and immune cell data. Additionally, the risk prognosis model and the neural network diagnostic model were established to further investigate these seven hub genes. In order to achieve precision treatment for breast cancer (BRCA), based on the RNA transcriptomic data of the seven genes, 1226 BRCA patients were divided into two subtypes: BRCA subtype 1 and BRCA subtype 2. By studying and comparing the immune microenvironment, investigating the mechanisms of differential gene expression, and exploring the mechanisms of subnetworks, we aim to explore the clinical differences in the presentation of BRCA subtypes and achieve precision treatment for BRCA. Finally, qRT-PCR experiments were conducted to validate the conclusions of the bioinformatics analysis.

RESULTS

The 7 hub genes showed good diagnostic independence and can serve as excellent biomarkers for molecular diagnosis. However, they do not perform well as independent prognostic molecular markers for BRCA patients. When predicting the survival of BRCA patients, their AUC values at 1 year, 3 years, and 5 years are mostly below 0.5. Nevertheless, through the establishment of the risk prognosis model considering the combined effect of the seven hub genes, it was found that the survival prediction of BRCA patients can be significantly improved. The risk prognosis model, compared to the independent use of the seven hub genes as prognostic markers, achieved higher timeROC AUC values at 1 year, 3 years, and 5 years, with values of 0.651, 0.669, and 0.641 respectively. Additionally, the neural network diagnostic model constructed from the 7 genes performs well in diagnosing BRCA, with an AUC value of 0.94, accurately identifying BRCA patients. The two subtypes identified by the seven hub genes exhibited significant differences in survival period, with subtype 1 having a poor prognosis. The differential mechanisms between the two subtypes mainly originate from regulatory differences in the immune microenvironment. Finally, the results of this study's bioinformatics analysis were validated through qRT-PCR experiments.

CONCLUSION

7 hub genes serve as excellent independent biomarkers for molecular diagnosis, and the neural network diagnostic model can accurately distinguish BRCA patients. In addition, based on the expression levels of these seven genes in BRCA patients, two subtypes can be reliably identified: BRCA subtype 1 and BRCA subtype 2, and these two subtypes showed significant differences in BRCA patient survival prognosis, proportion of immune cells, and expression levels of immune cells. Among them, patients with subtype 1 of BRCA had a poor prognosis.

Cholesterol transport and beyond: Illuminating the versatile functions of HDL apolipoproteins through structural insights and functional implications

High-density lipoproteins (HDLs) play a vital role in lipid metabolism and cardiovascular health, as they are intricately involved in cholesterol transport and inflammation modulation. The proteome of HDL particles is indeed complex and distinct from other components in the bloodstream. Proteomics studies have identified nearly 285 different proteins associated with HDL; however, this review focuses more on the 15 or so traditionally named "apo" lipoproteins. Important lipid metabolizing enzymes closely working with the apolipoproteins are also discussed. Apolipoproteins stand out for their integral role in HDL stability, structure, function, and metabolism. The unique structure and functions of each apolipoprotein influence important processes such as inflammation regulation and lipid metabolism. These interactions also shape the stability and performance of HDL particles. HDLs apolipoproteins have multifaceted roles beyond cardiovascular diseases (CVDs) and are involved in various physiological processes and disease states. Therefore, a detailed exploration of these apolipoproteins can offer valuable insights into potential diagnostic markers and therapeutic targets. This comprehensive review article aims to provide an in-depth understanding of HDL apolipoproteins, highlighting their distinct structures, functions, and contributions to various physiological processes. Exploiting this knowledge holds great potential for improving HDL function, enhancing cholesterol efflux, and modulating inflammatory processes, ultimately benefiting individuals by limiting the risks associated with CVDs and other inflammation-based pathologies. Understanding the nature of all 15 apolipoproteins expands our knowledge of HDL metabolism, sheds light on their pathological implications, and paves the way for advancements in the diagnosis, prevention, and treatment of lipid and inflammatory-related disorders.

Consumption of dietary fiber and APOA5 genetic variants in metabolic syndrome: baseline data from the Korean Medicine Daejeon Citizen Cohort Study

BACKGROUND

Consumption of dietary fiber has been suggested as an important aspect of a healthy diet to reduce the risk of metabolic syndrome (MetS), including cardiovascular disease. The role of fiber intake in MetS might differ by individual genetic susceptibility. APOA5 encodes a regulator of plasma triglyceride levels, which impacts the related mechanisms of MetS. This study investigated the association between dietary fiber and the risk of MetS, assessing their associations according to APOA5 genetic variants.

METHODS

A total of 1985 participants aged 30-55 years were included from a cross-sectional study based on the Korean Medicine Daejeon Citizen Cohort study at baseline (2017-2019). Dietary fiber intake was measured using a semiquantitative food frequency questionnaire. The APOA5 polymorphisms (rs2266788 A > G, rs662799 A > G, and rs651821 T > C) were genotyped using the Asia Precision Medicine Research Array. Logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (95% CIs).

RESULTS

A higher consumption of dietary fiber was associated with a lower prevalence of MetS (P = 0.025). Among the components of MetS, an inverse association with dietary fiber was observed in increased waist circumference (OR, 95% CI = 0.60, 0.41-0.88, P for trend = 0.009) and elevated triglycerides (OR, 95% CI = 0.69, 0.50-0.96, P for trend = 0.012). Regarding the interaction with APOA5 genetic variants, a stronger association with dietary fiber intake was shown in G allele carriers of rs662799 than in A/A carriers (OR, 95% CI = 2.34, 1.59-3.44, P for interaction = 0.024) and in C allele carriers of rs651821 than in T/T carriers (OR, 95% CI = 2.35, 1.59-3.46, P for interaction = 0.027).

CONCLUSIONS

The findings of this study suggest that the benefits of dietary fiber on the risk of MetS could be modified by genetic variants of the APOA5 gene, providing a more effective strategy for preventing MetS.

Genetic variation in apolipoprotein A-V in hypertriglyceridemia

PURPOSE OF REVIEW

While biallelic rare APOA5 pathogenic loss-of-function (LOF) variants cause familial chylomicronemia syndrome, heterozygosity for such variants is associated with highly variable triglyceride phenotypes ranging from normal to severe hypertriglyceridemia, often in the same individual at different time points. Here we provide an updated overview of rare APOA5 variants in hypertriglyceridemia.

RECENT FINDINGS

Currently, most variants in APOA5 that are considered to be pathogenic according to guidelines of the American College of Medical Genetics and Genomics are those resulting in premature termination codons. There are minimal high quality functional data on the impact of most rare APOA5 missense variants; many are considered as variants of unknown or uncertain significance. Furthermore, particular common polymorphisms of APOA5 , such as p.Ser19Trp and p.Gly185Cys in Caucasian and Asian populations, respectively, are statistically overrepresented in hypertriglyceridemia cohorts and are sometimes misattributed as being causal for chylomicronemia, when they are merely risk alleles for hypertriglyceridemia.

SUMMARY

Both biallelic and monoallelic LOF variants in APOA5 are associated with severe hypertriglyceridemia, although the biochemical phenotype in the monoallelic state is highly variable and is often exacerbated by secondary factors. Currently, with few exceptions, the principal definitive mechanism for APOA5 pathogenicity is through premature truncation. The pathogenic mechanisms of most missense variants in APOA5 remain unclear and require additional functional experiments or family studies.

Depletion of ApoA5 aggravates spontaneous and diet-induced nonalcoholic fatty liver disease by reducing hepatic NR1D1 in hamsters

Background: ApoA5 mainly synthesized and secreted by liver is a key modulator of lipoprotein lipase (LPL) activity and triglyceride-rich lipoproteins (TRLs). Although the role of ApoA5 in extrahepatic triglyceride (TG) metabolism in circulation has been well documented, the relationship between ApoA5 and nonalcoholic fatty liver disease (NAFLD) remains incompletely understood and the underlying molecular mechanism still needs to be elucidated. Methods: We used CRISPR/Cas9 gene editing to delete Apoa5 gene from Syrian golden hamster, a small rodent model replicating human metabolic features. Then, the ApoA5-deficient (ApoA5-/-) hamsters were used to investigate NAFLD with or without challenging a high fat diet (HFD). Results: ApoA5-/- hamsters exhibited hypertriglyceridemia (HTG) with markedly elevated TG levels at 2300 mg/dL and hepatic steatosis on a regular chow diet, accompanied with an increase in the expression levels of genes regulating lipolysis and small adipocytes in the adipose tissue. An HFD challenge predisposed ApoA5-/- hamsters to severe HTG (sHTG) and nonalcoholic steatohepatitis (NASH). Mechanistic studies in vitro and in vivo revealed that targeting ApoA5 disrupted NR1D1 mRNA stability in the HepG2 cells and the liver to reduce both mRNA and protein levels of NR1D1, respectively. Overexpression of human NR1D1 by adeno-associated virus 8 (AAV8) in the livers of ApoA5-/- hamsters significantly ameliorated fatty liver without affecting plasma lipid levels. Moreover, restoration of hepatic ApoA5 or activation of UCP1 in brown adipose tissue (BAT) by cold exposure or CL316243 administration could significantly correct sHTG and hepatic steatosis in ApoA5-/- hamsters. Conclusions: Our data demonstrate that HTG caused by ApoA5 deficiency in hamsters is sufficient to elicit hepatic steatosis and HFD aggravates NAFLD by reducing hepatic NR1D1 mRNA and protein levels, which provides a mechanistic link between ApoA5 and NAFLD and suggests the new insights into the potential therapeutic approaches for the treatment of HTG and the related disorders due to ApoA5 deficiency in the clinical trials in future.

Nomogram developed with APOA5 genetic variant rs662799 and clinical characteristics predicting risk of essential hypertension in a Chinese population

Background

The apolipoprotein A5 (APOA5) gene has been identified as a key regulatory factor in triglyceride (TG) metabolism and plasma lipid levels. Genetic polymorphisms of APOA5 have been linked to an elevated risk of atherosclerosis, metabolic syndrome, stroke, and coronary artery disease. The rs662799 variant is a single nucleotide polymorphism (SNP) that occurs at a specific position within the APOA5 gene. However, the association between rs662799 polymorphism and essential hypertension (EHT) remains unclear. The study aimed to comprehensively examine the potential correlation between the rs662799 polymorphism and the susceptibility to EHT in a Chinese population using a systematic analysis.

Methods

In a case study conducted at the First Affiliated Hospital of Xinjiang Medical University between Jan 2019 and Dec 2021, we examined a total of 700 cases of EHT along with 700 corresponding controls. The serum concentrations of various lipid parameters were measured by enzymatic method, while the genotyping of the SNP was performed using the improved multiplex ligation detection reaction (iMLDR) method. The independent risk factors of EHT were identified from multivariable logistic regression analysis. The nomogram prediction model that incorporated the APOA5 genetic variations and clinical variables was constructed. In addition, receiver operating characteristic (ROC) curve and Hosmer-Lemeshow test were conducted to determine the performance of the nomogram model. The optimal threshold was calculated based on Youden index.

Results

Our study revealed a higher prevalence of the G allele of the rs662799 variant in individuals diagnosed with EHT compared to the control group. Logistic regression analysis indicated that with the adjustment of other confounders, the observed difference between the two groups remained statistically significant [odds ratio (OR) =1.519; 95% confidence interval (CI): 1.203-1.917; P<0.001]. Based on 8 independent risk factors including APOA5 rs662799 G allele, age, body mass index (BMI), smoking, diabetes, education, low-density lipoprotein cholesterol (LDL-C), and TG, we constructed a novel risk evaluation nomogram of EHT. The area under the ROC curve of the nomogram was 0.722 (95% CI: 0.693-0.752; P<0.001) and 0.747 (95% CI: 0.690-0.804; P<0.001) for the training and validation set, respectively. Furthermore, the Hosmer-Lemeshow test indicated excellent calibration performance, yielding P values of 0.969 for the training set and 0.761 for the validation set.

Conclusions

In our study, the rs662799 variant of the APOA5 gene was significantly associated with susceptibility to EHT. A nomogram for the early prediction of EHT in in the Chinese population was successfully constructed and validated. The nomogram can provide a visual assessment of the risk of EHT for clinical consultation.

Lipoprotein Lipase Activity Does Not Differ in the Serum Environment of Vegans and Omnivores

Although vegan diets have been reported to be associated with a reduced risk of cardiovascular disease, it was not known whether this might be partly due to vegan diets' effects on plasma triglyceride metabolism. This study aimed to investigate if there are differences in the activity of lipoprotein lipase (LPL), an enzyme that functions at the vascular endothelium and is responsible for triglyceride breakdown, in sera obtained from vegans and omnivores. LPL activity was assessed using isothermal titration calorimetry, which allows measurements in undiluted serum samples, mimicking physiological conditions. Fasted sera from 31 healthy participants (12F 2M vegans, 11F 6M omnivores) were analyzed. The results indicated no significant differences in average LPL activity between the vegan and omnivore groups. Interestingly, despite similar triglyceride levels, there were considerable variations in LPL activity and total very-low-density lipoprotein triglyceride breakdowns between individuals within both groups. Biomarker analysis showed that vegans had lower total cholesterol and LDL-C levels compared to omnivores. These findings suggest that the lipid-related benefits of a vegan diet, in terms of atherogenic risk, may primarily stem from cholesterol reduction rather than affecting serum as a medium for LPL-mediated triglyceride breakdown. In healthy individuals, lipid-related changes in serum composition in response to a vegan diet are likely overshadowed by genetic or other lifestyle factors.

Strategies for consistent and automated quantification of HDL proteome using data-independent acquisition (DIA)

The introduction of mass spectrometry-based proteomics has revolutionized HDL field, with the description, characterization and implication of HDL-associated proteins in an array of pathologies. However, acquiring robust, reproducible data is still a challenge in the quantitative assessment of HDL proteome. Data-independent acquisition (DIA) is a mass spectrometry methodology that allows the acquisition of reproducible data, but data analysis remains a challenge in the field. Up to date, there is no consensus in how to process DIA-derived data for HDL proteomics. Here, we developed a pipeline aiming to standardize HDL proteome quantification. We optimized instrument parameters, and compared the performance of four freely available, user-friendly software tools (DIA-NN, EncyclopeDIA, MaxDIA and Skyline) in processing DIA data. Importantly, pooled samples were used as quality controls throughout our experimental setup. A carefully evaluation of precision, linearity, and detection limits, first using E. coli background for HDL proteomics, and second using HDL proteome and synthetic peptides, was undertaken. Finally, as a proof of concept, we employed our optimized and automated pipeline to quantify the proteome of HDL and apolipoprotein B (APOB)-containing lipoproteins. Our results show that determination of precision is key to confidently and consistently quantify HDL proteins. Taking this precaution, any of the available software tested here would be appropriate for quantification of HDL proteome, although their performance varied considerably.

Advances in the study of the pathogenesis of obesity: Based on apolipoproteins

Obesity is a state presented by excessive accumulation and abnormal distribution of body fat, with metabolic disorders being one of its distinguishing features. Obesity is associated with dyslipidemia, apolipoproteins are important structural components of plasma lipoproteins, which influence lipid metabolism in the body by participating in lipoprotein metabolism and are closely related to the progression of obesity. Apolipoproteins influence the progression of obesity from lipid metabolism, energy expenditure and inflammatory response. In this review, we discuss the alterations of apolipoproteins in obesity, understand the potential mechanisms by which apolipoproteins affect obesity, as well as provide new targets for the treatment of obesity.

Gut Microbiota Remodeling and Intestinal Adaptation to Lipid Malabsorption After Enteroendocrine Cell Loss in Adult Mice

BACKGROUND & AIMS

Enteroendocrine cells (EECs) and their hormones are essential regulators of whole-body energy homeostasis. EECs sense luminal nutrients and microbial metabolites and subsequently secrete various hormones acting locally or at a distance. Impaired development of EECs during embryogenesis is life-threatening in newborn mice and humans due to compromised nutrient absorption. However, the physiological importance of the EEC system in adult mice has yet to be directedly studied. Herein, we aimed to determine the long-term consequences of a total loss of EECs in healthy adults on energy metabolism, intestinal transcriptome, and microbiota.

METHODS

We depleted intestinal EECs by tamoxifen treatment of adult Neurog3^fl/fl; Villin-CreER^T2 male mice. We studied intestinal cell differentiation, food efficiency, lipid absorption, microbiota composition, fecal metabolites, and transcriptomic responses in the proximal and distal small intestines of mice lacking EECs. We also determined the high-fat diet-induced transcriptomic changes in sorted Neurog3^eYFP/+ EECs.

RESULTS

Induction of EEC deficiency in adults is not life-threatening unless fed with a high-fat diet. Under a standard chow diet, mice lose 10% of weight due to impaired food efficiency. Blood concentrations of cholesterol, triglycerides, and free fatty acids are reduced, and lipid absorption is impaired and delayed in the distal small intestine. Genes controlling lipogenesis, carbohydrate metabolism, and neoglucogenesis are upregulated. Microbiota composition is rapidly altered after EECs depletion and is characterized by decreased a-diversity. Bacteroides and Lactobacillus were progressively enriched, whereas Lachnospiraceae declined without impacting fecal short-chain fatty acid concentrations.

CONCLUSIONS

EECs are dispensable for survival in adult male mice under a standard chow diet. The absence of EECs impairs intestinal lipid absorption, leading to transcriptomic and metabolic adaptations and remodeling of the gut microbiota.

Genetic association analysis of rs662799 ( − 1131A > G) polymorphism of APOA5 gene with morphometric and physio-metric traits using multiplex PCR

Background

The apolipoprotein A5 (APOA5) gene, significantly expressed in liver, has been involved in regulation of triglyceride metabolism, plasma lipid levels, serum adipokine levels and cardiovascular traits. A single-nucleotide polymorphism rs662799 ( − 1131A > G), 2 Kb upstream in the promoter region of this gene, causes decrease in the concentration of the product coded by this gene; hence, it may be responsible for impairments in normal function of the gene, ultimately leading to disease condition. Keeping in view the importance of APOA5 gene, the aim of the present study was to examine the association of genetic variant rs662799 of APOA5 gene with two quantitative traits simultaneously, viz. body mass index and blood pressure.

Results

The study involved a population of 246 subjects from North Indian region. Measurements of morphometric and physio-metric parameters were recorded using standard measures. Genotyping of APOA5 gene polymorphism (rs662799) using Tetra-primer amplification refractory mutation system PCR was performed. Statistical analyses were carried out using MS-Excel and SigmaPlot, and significance level was setup as p < 0.05. The allelic distribution of rs662799 polymorphism in this population was 77% for major allele (A) and 23% for minor allele (G). Significant association of rs662799 with increased body mass index and blood pressure was observed, with the presence of allele G. Under recessive genetic model, rs662799 polymorphism conferred a 17.71-fold risk of elevated body mass index (OR = 17.71, p < 0.001, CI (95%) = 4.05–77.46), and for increase in blood pressure, 3.79- and 3.83-fold risk of systolic blood pressure and diastolic blood pressure (OR = 3.792, p = 0.023, CI (95%) = 1.25–11.509 and OR = 3.83, p = 0.012, CI (95%) = 1.375–10.68, respectively) was observed. Under dominant genetic model, it showed a 3.060-fold risk of increase in body mass index (OR = 3.060, p < 0.001, CI (95%) = 1.78–5.25).

Conclusions

G allele of rs662799 of APOA5 gene showed significant susceptible association with BMI and BP. This study may be helpful for clinicians and researchers to investigate the diagnostic and prognostic value of the gene in question.

In the context of the triple burden of malnutrition: A systematic review of gene-diet interactions and nutritional status

Genetic background interacts with dietary components to modulate nutritional health status. This study aimed to review the evidence for gene-diet interactions in all forms of malnutrition. A comprehensive systematic literature search was conducted through April 2021 to identify observational and intervention studies reporting the effects of gene-diet interactions in over-nutrition, under-nutrition and micronutrient status. Risk of publication bias was assessed using the Quality Criteria Checklist and a tool specifically designed for gene-diet interaction research. 167 studies from 27 populations were included. The majority of studies investigated single nucleotide polymorphisms (SNPs) in overnutrition (n = 158). Diets rich in whole grains, vegetables, fruits and low in total and saturated fats, such as Mediterranean and DASH diets, showed promising effects for reducing obesity risk among individuals who had higher genetic risk scores for obesity, particularly the risk alleles carriers of FTO rs9939609, rs1121980 and rs1421085. Other SNPs in MC4R, PPARG and APOA5 genes were also commonly studied for interaction with diet on overnutrition though findings were inconclusive. Only limited data were found related to undernutrition (n = 1) and micronutrient status (n = 9). The findings on gene-diet interactions in this review highlight the importance of personalized nutrition, and more research on undernutrition and micronutrient status is warranted.

The Regulation of Triacylglycerol Metabolism and Lipoprotein Lipase Activity

Triacylglycerol (TG) metabolism is tightly regulated to maintain a pool of TG within circulating lipoproteins that can be hydrolyzed in a tissue-specific manner by lipoprotein lipase (LPL) to enable the delivery of fatty acids to adipose or oxidative tissues as needed. Elevated serum TG concentrations, which result from a deficiency of LPL activity or, more commonly, an imbalance in the regulation of tissue-specific LPL activities, have been associated with an increased risk of atherosclerotic cardiovascular disease through multiple studies. Among the most critical LPL regulators are the angiopoietin-like (ANGPTL) proteins ANGPTL3, ANGPTL4, and ANGPTL8, and a number of different apolipoproteins including apolipoprotein A5 (ApoA5), apolipoprotein C2 (ApoC2), and apolipoprotein C3 (ApoC3). These ANGPTLs and apolipoproteins work together to orchestrate LPL activity and therefore play pivotal roles in TG partitioning, hydrolysis, and utilization. This review summarizes the mechanisms of action, epidemiological findings, and genetic data most relevant to these ANGPTLs and apolipoproteins. The interplay between these important regulators of TG metabolism in both fasted and fed states is highlighted with a holistic view toward understanding key concepts and interactions. Strategies for developing safe and effective therapeutics to reduce circulating TG by selectively targeting these ANGPTLs and apolipoproteins are also discussed.

Genetic Association between Different Metabolic Variants in APOA5 and PLIN1 in Type 2 Diabetes Mellitus among the Western Saudi Population: Case-Control Study

Type 2 diabetes mellitus (T2DM) is a multifactorial disease with a high global incidence. Hypertriglyceridemia is a major risk factor for both cardiovascular disease and T2DM. In this study, we determined the allele and genotype frequencies of apolipoprotein A5 (APOA5) single nucleotide polymorphism (SNP) rs662799 and perilipin 1 (PLIN1) SNPs rs894160, rs6496589, and rs1052700 and evaluated their association with T2DM risk in western Saudis. Only rs6496589 was found to be significantly associated with T2DM risk. We determined the risk allele for each SNP based on relative risk, and found that the G allele of rs662799, T allele of rs894160, G allele of r6496589, and T allele of rs1052700 correlated with T2DM risk. The effect of each SNP on T2DM risk and five of its clinical phenotypes was explored using multiple logistic regression. We found significant correlations between the C/G and G/G genotypes of rs6496589 and T2DM risk in the unadjusted model, whereas G/G was the only genotype that correlated with the risk of T2DM in the adjusted model. There was no significant correlation between rs662799, rs894160, and rs1052700 genotypes and T2DM risk. In conclusion, we have identified novel risk alleles and genotypes that contribute to genetic risk for T2DM in the western Saudi population.

Maternal Nutrient Restriction Disrupts Gene Expression and Metabolites Associated with Urea Cycle, Steroid Synthesis, Glucose Homeostasis, and Glucuronidation in Fetal Calf Liver

This study aimed to understand the mechanisms underlying the effects of maternal undernutrition (MUN) on liver growth and metabolism in Japanese Black fetal calves (8.5 months in utero) using an approach that integrates metabolomics and transcriptomics. Dams were fed 60% (low-nutrition; LN) or 120% (high-nutrition; HN) of their overall nutritional requirements during gestation. We found that MUN markedly decreased the body and liver weights of the fetuses; metabolomic analysis revealed that aspartate, glycerol, alanine, gluconate 6-phosphate, and ophthalmate levels were decreased, whereas UDP-glucose, UDP-glucuronate, octanoate, and 2-hydroxybutyrate levels were decreased in the LN fetal liver (p ≤ 0.05). According to metabolite set enrichment analysis, the highly different metabolites were associated with metabolisms including the arginine and proline metabolism, nucleotide and sugar metabolism, propanoate metabolism, glutamate metabolism, porphyrin metabolism, and urea cycle. Transcriptomic and qPCR analyses revealed that MUN upregulated QRFPR and downregulated genes associated with the glucose homeostasis (G6PC, PCK1, DPP4), ketogenesis (HMGCS2), glucuronidation (UGT1A1, UGT1A6, UGT2A1), lipid metabolism (ANGPTL4, APOA5, FADS2), cholesterol and steroid homeostasis (FDPS, HSD11B1, HSD17B6), and urea cycle (CPS1, ASS1, ASL, ARG2). These metabolic pathways were extracted as relevant terms in subsequent gene ontology/pathway analyses. Collectively, these results indicate that the citrate cycle was maintained at the expense of activities of the energy metabolism, glucuronidation, steroid hormone homeostasis, and urea cycle in the liver of MUN fetuses.

Lipopolysaccharide-Induced Transcriptional Changes in LBP-Deficient Rat and Its Possible Implications for Liver Dysregulation during Sepsis

Sepsis is an organ dysfunction caused by the dysregulated inflammatory response to infection. Lipopolysaccharide-binding protein (LBP) binds to lipopolysaccharide (LPS) and modulates the inflammatory response. A rare systematic study has been reported to detect the effect of LBP gene during LPS-induced sepsis. Herein, we explored the RNA sequencing technology to profile the transcriptomic changes in liver tissue between LBP-deficient rats and WT rats at multiple time points after LPS administration. We proceeded RNA sequencing of liver tissue to search differentially expressed genes (DEGs) and enriched biological processes and pathways between WT and LBP-deficient groups at 0 h, 6 h, and 24 h. In total, 168, 284, and 307 DEGs were identified at 0 h, 6 h, and 24 h, respectively, including Lrp5, Cyp7a1, Nfkbiz, Sigmar1, Fabp7, and Hao1, which are related to the inflammatory or lipid-related process. Functional enrichment analysis revealed that inflammatory response to LPS mediated by Ifng, Cxcl10, Serpine1, and Lbp was enhanced at 6 h, while lipid-related metabolism associated with C5, Cyp4a1, and Eci1 was enriched at 24 h after LPS administration in the WT samples. The inflammatory process was not found when the LBP gene was knocked out; lipid-related metabolic process and peroxisome proliferator-activated receptor (PPAR) signaling pathway mediated by Dhrs7b and Tysnd1 were significantly activated in LBP-deficient samples. Our study suggested that the invading LPS may interplay with LBP to activate the nuclear factor kappa B (NF-κB) signaling pathway and trigger uncontrolled inflammatory response. However, when inhibiting the activity of NF-κB, lipid-related metabolism would make bacteria removal via the effect on the PPAR signaling pathway in the absence of LBP gene. We also compared the serum lactate dehydrogenase (LDH) and alkaline phosphatase (ALP) levels using the biochemistry analyzer and analyzed the expression of high mobility group box 1 (HMGB1) and cleaved-caspase 3 with immunohistochemistry, which further validated our conclusion.

Genetic Regulatory Networks of Apolipoproteins and Associated Medical Risks

Apolipoproteins (APO proteins) are the lipoprotein family proteins that play key roles in transporting lipoproteins all over the body. There are nearly more than twenty members reported in the APO protein family, among which the A, B, C, E, and L play major roles in contributing genetic risks to several disorders. Among these genetic risks, the single nucleotide polymorphisms (SNPs), involving the variation of single nucleotide base pairs, and their contributing polymorphisms play crucial roles in the apolipoprotein family and its concordant disease heterogeneity that have predominantly recurred through the years. In this review, we have contributed a handful of information on such genetic polymorphisms that include APOE, ApoA1/B ratio, and A1/C3/A4/A5 gene cluster-based population genetic studies carried throughout the world, to elaborately discuss the effects of various genetic polymorphisms in imparting various medical conditions, such as obesity, cardiovascular, stroke, Alzheimer's disease, diabetes, vascular complications, and other associated risks.

Appraisal of Gene-Environment Interactions in GWAS for Evidence-Based Precision Nutrition Implementation

PURPOSE OF REVIEW

This review aims to analyse the currently reported gene-environment (G × E) interactions in genome-wide association studies (GWAS), involving environmental factors such as lifestyle and dietary habits related to metabolic syndrome phenotypes. For this purpose, the present manuscript reviews the available GWAS registered on the GWAS Catalog reporting the interaction between environmental factors and metabolic syndrome traits.

RECENT FINDINGS

Advances in omics-related analytical and computational approaches in recent years have led to a better understanding of the biological processes underlying these G × E interactions. A total of 42 GWAS were analysed, reporting over 300 loci interacting with environmental factors. Alcohol consumption, sleep time, smoking habit and physical activity were the most studied environmental factors with significant G × E interactions. The implementation of more comprehensive GWAS will provide a better understanding of the metabolic processes that determine individual responses to environmental exposures and their association with the development of chronic diseases such as obesity and the metabolic syndrome. This will facilitate the development of precision approaches for better prevention, management and treatment of these diseases.

Supplementation with Lactiplantibacillus plantarum IMC 510 Modifies Microbiota Composition and Prevents Body Weight Gain Induced by Cafeteria Diet in Rats

Changes in functionality and composition of gut microbiota (GM) have been associated and may contribute to the development and maintenance of obesity and related diseases. The aim of our study was to investigate for the first time the impact of Lactiplantibacillus (L.) plantarum IMC 510 in a rat model of diet-induced obesity, specifically in the cafeteria (CAF) diet. This diet provides a strong motivation to voluntary overeat, due to the palatability and variety of selected energy-dense foods. The oral administration for 84 days of this probiotic strain, added to the CAF diet, decreased food intake and body weight gain. Accordingly, it ameliorated body mass index, liver and white adipose tissue weight, hepatic lipid accumulation, adipocyte size, serum parameters, including glycemia and low-density lipoprotein levels, in CAF fed rats, potentially through leptin control. In this scenario, L. plantarum IMC 510 showed also beneficial effects on GM, limiting the microbial imbalance established by long exposure to CAF diet and preserving the proportion of different bacterial taxa. Further research is necessary to better elucidate the relationship between GM and overweight and then the mechanism of action by which L. plantarum IMC 510 modifies weight. However, these promising results prompt a clear advantage of probiotic supplementation and identify a new potential probiotic as a novel and safe therapeutic approach in obesity prevention and management.

Apolipoprotein A5 controls fructose-induced metabolic dysregulation in mice

BACKGROUND AND AIMS

Western dietary habits are partially characterized by increased uptake of fructose, which contributes to metabolic dysregulation and associated liver diseases. For example, a diet enriched with fructose drives insulin resistance and non-alcoholic fatty liver disease (NAFLD). The molecular hubs that control fructose-induced metabolic dysregulation are poorly understood. Apolipoprotein A5 (apoA5) controls triglyceride metabolism with a putative role in hepatic lipid deposition. We explored apoA5 as a rheostat for fructose-induced hepatic and metabolic disease in mammals.

METHODS AND RESULTS

ApoA5 knock out (-/-) and wildtype (wt) mice were fed with high fructose diet or standard diet for 10 weeks. Afterwards, we conducted a metabolic characterization by insulin tolerance test as well as oral glucose tolerance test. Additionally, hepatic lipid content as well as transcription patterns of key enzymes and transcription factors in glucose and lipid metabolism were evaluated. Despite comparable body weight, insulin sensitivity was significantly improved in high fructose diet fed apoA5 (-/-) when compared to wildtype mice on the same diet. In parallel, hepatic triglyceride content was significantly lower in apoA5 (-/-) mice than in wt mice. No difference was seen between apoA5 (-/-) and wt mice on a standard diet.

CONCLUSION

ApoA5 is involved in fructose-induced metabolic dysregulation and associated hepatic steatosis suggesting that apoA5 may be a novel target to treat metabolic diseases.

Dissecting the Gene Expression Networks Associated with Variations in the Major Components of the Fatty Acid Semimembranosus Muscle Profile in Large White Heavy Pigs

Simple Summary

The amount and fatty acid composition of intramuscular fat are important features for the qualitative characteristics of processed and fresh meat products, but the knowledge of the key molecular drivers controlling these traits is still scant. To this aim, the present study investigated the co-expression networks of genes related to variations in the major fatty acids deposited in pig Semimembranosus muscle. Palmitic and palmitoleic acid contents were associated with a downregulation of genes involved in autophagy, mitochondrial fusion, and mitochondrial activity, suggesting that the deposition of these fatty acids may be enhanced in muscles with a reduced mitochondrial function. A higher proportion of oleic acid and a reduction in the percentages of n-6 and n-3 polyunsaturated fatty acids were related to changes in the mRNA levels of genes involved in Mitogen-Activated Protein Kinase (MAPK) signaling. The obtained results indicated gene expression networks and new candidate genes associated with the studied traits. Further studies are needed to confirm our results and identify in the discussed genes molecular markers for future selection schemes aimed at improving pork nutritional and technological quality. Furthermore, as pigs are considered reliable animal models for several human conditions, the obtained results may also be of interest for improving the knowledge of the molecular pathways associated with obesity and diabetes.

Abstract

To date, high-throughput technology such as RNA-sequencing has been successfully applied in livestock sciences to investigate molecular networks involved in complex traits, such as meat quality. Pork quality depends on several organoleptic, technological, and nutritional characteristics, and it is also influenced by the fatty acid (FA) composition of intramuscular fat (IMF). To explore the molecular networks associated with different IMF FA compositions, the Semimembranosus muscle (SM) from two groups of Italian Large White (ILW) heavy pigs divergent for SM IMF content was investigated using transcriptome analysis. After alignment and normalization, the obtained gene counts were used to perform the Weighted Correlation Network Analysis (WGCNA package in R environment). Palmitic and palmitoleic contents showed association with the same gene modules, comprising genes significantly enriched in autophagy, mitochondrial fusion, and mitochondrial activity. Among the key genes related to these FAs, we found TEAD4, a gene regulating mitochondrial activity that seems to be a promising candidate for further studies. On the other hand, the genes comprised in the modules associated with the IMF contents of oleic, n-6, and n-3 polyunsaturated FAs (PUFAs) were significantly enriched in Mitogen-Activated Protein Kinase (MAPK) signaling, in agreement with previous studies suggesting that several MAPK players may have a primary role in regulating lipid deposition. These results give an insight into the molecular cascade associated with different IMF FA composition in ILW heavy pigs. Further studies are needed to validate the results and confirm whether some of the identified key genes may be effective candidates for pork quality.

Multiple Selection Criteria for Probiotic Strains with High Potential for Obesity Management

Since alterations of the gut microbiota have been shown to play a major role in obesity, probiotics have attracted attention. Our aim was to identify probiotic candidates for the management of obesity using a combination of in vitro and in vivo approaches. We evaluated in vitro the ability of 23 strains to limit lipid accumulation in adipocytes and to enhance the secretion of satiety-promoting gut peptide in enteroendocrine cells. Following the in vitro screening, selected strains were further investigated in vivo, single, or as mixtures, using a murine model of diet-induced obesity. Strain Bifidobacterium longum PI10 administrated alone and the mixture of B. animalis subsp. lactis LA804 and Lactobacillus gasseri LA806 limited body weight gain and reduced obesity-associated metabolic dysfunction and inflammation. These protective effects were associated with changes in the hypothalamic gene expression of leptin and leptin receptor as well as with changes in the composition of gut microbiota and the profile of bile acids. This study provides crucial clues to identify new potential probiotics as effective therapeutic approaches in the management of obesity, while also providing some insights into their mechanisms of action.

Understanding the genetic architecture of the metabolically unhealthy normal weight and metabolically healthy obese phenotypes in a Korean population

Understanding the mechanisms underlying the metabolically unhealthy normal weight (MUHNW) and metabolically healthy obese (MHO) phenotypes is important for developing strategies to prevent cardiometabolic diseases. Here, we conducted genome-wide association studies (GWASs) to identify the MUHNW and MHO genetic indices. The study dataset comprised genome-wide single-nucleotide polymorphism genotypes and epidemiological data from 49,915 subjects categorised into four phenotypes-metabolically healthy normal weight (MHNW), MUHNW, MHO, and metabolically unhealthy obese (MUHO). We conducted two GWASs using logistic regression analyses and adjustments for confounding variables (model 1: MHNW versus MUHNW and model 2: MHO versus MUHO). GCKR, ABCB11, CDKAL1, LPL, CDKN2B, NT5C2, APOA5, CETP, and APOC1 were associated with metabolically unhealthy phenotypes among normal weight individuals (model 1). LPL, APOA5, and CETP were associated with metabolically unhealthy phenotypes among obese individuals (model 2). The genes common to both models are related to lipid metabolism (LPL, APOA5, and CETP), and those associated with model 1 are related to insulin or glucose metabolism (GCKR, CDKAL1, and CDKN2B). This study reveals the genetic architecture of the MUHNW and MHO phenotypes in a Korean population-based cohort. These findings could help identify individuals at a high metabolic risk in normal weight and obese populations and provide potential novel targets for the management of metabolically unhealthy phenotypes.

The Rise of ST-Elevation Myocardial Infarction in Women of Northeast China

The women of China's Liaoning province display some morbidities in ways that defy medical explanation. Women have higher rates of hypertension, hypercholesterolemia, and metabolic syndrome than men, an anomaly for all three conditions. Most of these patients also suffer from Type 2 Diabetes Mellitus (T2DM) while there was a negative association between being female and T2DM for the rest of China. Each of these conditions can exist independently, but the increase in both their rates and congruence is a recent phenomenon. Stranger still is that Liaoning women are now presenting in hospital emergency departments with ST-Elevation Myocardial Infarction (STEMI), while diabetics predominantly suffer more benign Non-STEMI (NSTEMI) events. Confounding factors in any attempt to study this phenomenon include trace metals like manganese that have been shown to reduce systolic blood pressure in Asian men and raise it in Asian women. Some of the phenomenon may also be associated with the gene for Apolipoprotein 5, but its recent nature suggests other factors besides lipid profiles. Trace metals in the air, water, and diet of Liaoning province, or any urban environment, could play a role.

Emerging functions of adipokines in linking the development of obesity and cardiovascular diseases

Increasing evidence shows that obesity is the critical factor in shaping cardio-metabolic phenotypes. However, the pathogenic mechanisms remain incompletely clarified. According to the published reports, adipose tissue communicates with several diverse organs, such as heart, lungs, and kidneys through the secretion of various cytokines named adipokines. The adipocytes isolated from obese mice or humans are dysfunctional with aberrant production of pro-inflammatory adipokines, which subsequently induce both acute and chronic inflammatory reaction and facilitate the process of cardio-metabolic disorder complications. Furthermore, the microenvironment within adipose tissue under obese status also influence the secretion of adipokines. Recently, given that several important adipokines have been completely researched and causally involved in various diseases, we could make a conclusion that adipokines play an essential role in modulating the development of cardio-metabolic disorder diseases, whereas several novel adipokines continue to be explored and elucidated. In the present review, we summarized the current knowledge of the microenvironment of adipose tissue and the published mechanisms whereby adipocytes affects obesity and cardiovascular diseases. On the other hand, we also provide the evidence to elucidate the functions of adipokines in controlling and regulating the inflammatory reactions which contribute to obesity and cardiovascular disease.

The APOA5-rs662799 Polymorphism Is a Determinant of Dyslipidemia in Vietnamese Primary School Children

Apolipoprotein A-V encoded by apolipoprotein 5 (APOA5) gene plays an important role in lipid metabolism, especially in the regulation of plasma triglycerol levels. The study aimed to evaluate the association of the APOA5-rs662799 polymorphism with dyslipidemia in Vietnamese children and the potential modification of obesity-related traits (body mass index, waist circumference, hip circumference, and waist-to-hip ratio) on this association. A case-control study was conducted with a total of 154 dyslipidemia cases and 389 controls at the age of 6 to 10 recruited at 31 primary schools in Hanoi city of Vietnam. Genotype for APOA5-rs662799 polymorphism was determined by the restriction fragment length polymorphism analysis. The association of APOA5-rs662799 polymorphism with dyslipidemia adjusting for age, sex, residence, and obesity-related traits was analyzed by binary logistic regression analysis. The results showed that in comparison with T/T and T/C carriers, the C/C carriers had a higher concentration of serum TAG in cases (p =0.049). Carriers of the C allele (C/C + T/C) had higher risk for developing dyslipidemia and hypertriglyceridemia than subjects with T/T genotype (odds ratio, OR = 1.7, p =0.0062 and OR = 1.6, p = 0.026, respectively). The association remained significant after adjusting for age, gender, residence, and obesity status (OR = 1.75, p = 0.006 and OR = 1.53, p = 0.049, respectively) or other obesity-related traits. The study suggested that the APOA5-rs662799 polymorphism may be a determinant of dyslipidemia and hypertriglyceridemia in Vietnamese children, independent of obesity-related traits.

Functional recombinant apolipoprotein A5 that is stable at high concentrations at physiological pH

APOA5 is a low-abundance exchangeable apolipoprotein that plays critical roles in human triglyceride (TG) metabolism. Indeed, aberrations in the plasma concentration or structure of APOA5 are linked to hypertriglyceridemia, hyperchylomicronemia, myocardial infarction risk, obesity, and coronary artery disease. While it has been successfully produced at low yield in bacteria, the resulting protein had limitations for structure-function studies due to its low solubility under physiological buffer conditions. We hypothesized that the yield and solubility of recombinant APOA5 could be increased by: i) engineering a fusion protein construct in a codon optimized expression vector, ii) optimizing an efficient refolding protocol, and iii) screening buffer systems at physiological pH. The result was a high-yield (25 mg/l) bacterial expression system that produces lipid-free APOA5 soluble at concentrations of up to 10 mg/ml at a pH of 7.8 in bicarbonate buffers. Physical characterization of lipid-free APOA5 indicated that it exists as an array of multimers in solution, and far UV circular dichroism analyses show differences in total α-helicity between acidic and neutral pH buffering conditions. The protein was functional in that it bound and emulsified multilamellar dimyristoyl-phosphatidylcholine vesicles and could inhibit postprandial plasma TG accumulation when injected into C57BL/6J mice orally gavaged with Intralipid.

The exchangeable apolipoproteins in lipid metabolism and obesity

Dyslipidemia, characterized by increased plasma levels of low-density lipoprotein cholesterol (LDL-C), very low-density lipoprotein cholesterol (VLDL-C), triglyceride (TG), and reduced plasma levels of high-density lipoprotein cholesterol (HDL-C), is confirmed as a hallmark of obesity and cardiovascular diseases (CVD), posing serious risks to the future health of humans. Thus, it is important to understand the molecular metabolism of dyslipidemia, which could help reduce the morbidity and mortality of obesity and CVD. Currently, several exchangeable apolipoproteins, such as apolipoprotein A1 (ApoA1), apolipoprotein A5 (ApoA5), apolipoprotein E (ApoE), and apolipoprotein C3 (ApoC3), have been verified to exert vital effects on modulating lipid metabolism and homeostasis both in plasma and in cells, which consequently affect dyslipidemia. In the present review, we summarize the findings of the effect of exchangeable apolipoproteins on affecting lipid metabolism in adipocytes and hepatocytes. Furthermore, we also provide new insights into the mechanisms by which the exchangeable apolipoproteins influence the pathogenesis of dyslipidemia and its related cardio-metabolic disorders.

New Insights into Apolipoprotein A5 and the Modulation of Human Adipose-derived Mesenchymal Stem Cells Adipogenesis

Background:

The hallmark of obesity is the excessive accumulation of triglyceride (TG) in adipose tissue. Apolipoprotein A5 (ApoA5) has been shown to influence the prevalence and pathogenesis of obesity. However, the underlying mechanisms remain to be clarified.

Methods:

Human adipose-derived mesenchymal stem cells (AMSCs) were treated with 600 ng/ml human recombinant ApoA5 protein. The effect of ApoA5 on intracellular TG content and adipogenic related factors expression were determined. Furthermore, the effect of ApoA5 on CIDE-C expression was also observed.

Results:

During the process of adipogenesis, ApoA5 treatment reduced the intracellular accumulation of lipid droplets and the TG levels; meanwhile, ApoA5 down-regulated the expression levels of adipogenic related factors, including CCAAT enhancer-binding proteins α/β (C/EBPα/β), fatty acid synthetase (FAS), and fatty acid-binding protein 4 (FABP4). Furthermore, the suppression of adipogenesis by ApoA5 was mediated through the inhibition of CIDE-C expression, an important factor which promotes the process of adipogenesis. However, over-expressing intracellular CIDE-C could lead to the loss-of-function of ApoA5 in inhibiting AMSCs adipogenesis.

Conclusions:

In conclusion, ApoA5 inhibits the adipogenic process of AMSCs through, at least partly, down-regulating CIDE-C expression. The present study provides novel mechanisms whereby ApoA5 prevents obesity via AMSCs in humans.

Changes in meta-transcriptome of rumen epimural microbial community and liver transcriptome in young calves with feed induced acidosis

The common management practices of dairy calves leads to increased starch concentration in feed, which subsequently may cause rumen acidosis while on milk and during weaning. Until recently, few attempts were undertaken to understand the health risks of prolonged ruminal acidosis in post weaning calves. Resultantly, the molecular changes in the digestive tracts in post-weaning calves with ruminal acidosis remain largely unexplored. In this study, we investigated the liver transcriptome changes along with its correlation with the rumen microbial rRNA expression changes in young calves using our model of feed induced ruminal acidosis. In this model, new born calves were fed a highly processed, starch-rich diet starting from one week of age through 16 weeks. A total of eight calves were involved in this study. Four of them were fed the acidosis-inducing diet (Treated) and the rest of the four were fed a standard starter diet (Control). Liver and rumen epithelial tissues were collected at necropsy at 17 weeks of age. Transcriptome analyses were carried out in the liver tissues and rRNA meta-transcriptome analysis were done using the rumen epithelial tissues. The correlation analysis was performed by comparing the liver mRNA expression with the rumen epithelial rRNA abundance at genus level. Calves with induced ruminal acidosis had significantly lower ruminal pH in comparison to the control group, in addition to significantly less weight-gain over the course of the experiment. In liver tissues, a total of 428 differentially expressed genes (DEGs) (fold-change, FC ≥ 1.5; adjusted P ≤ 0.1) were identified in treated group in comparison to control. Biological pathways enriched by these DEGs included cellular component organization, indicating the impact of ruminal acidosis on liver development in young calves. Specifically, the up-regulated genes were enriched in acute phase response (P < 0.01), pyruvate metabolic process (P < 0.01) and proton-acceptors (P ≪ 0.001), indicating the liver's response to feed induced acidosis at the transcriptome level. Twelve transferase activity related genes had significant correlation with rumen microbial rRNA expression changes. Among these genes, two up-regulated genes were reported with involvement in lipid metabolism in the liver, implying the direct effect of feed-induced acidosis on both the rumen microbial community and liver metabolism. Our study provides insight into the physiological remodeling in the liver resultant from the prolonged acidosis in post weaning calves, which may facilitate future RNA-seq based diagnosis and precision management of rumen acidosis in dairy calves.

Carbohydrate and sodium intake and physical activity interact with genetic risk scores of four genetic variants mainly related to lipid metabolism to modulate metabolic syndrome risk in Korean middle-aged adults

Metabolic syndrome (MetS) risk is influenced by genetic and environmental factors. The present study explored genetic risk scores (GRS) of genetic variants that influence the MetS and the effect of interactions between GRS and nutrient intake on MetS risk. The genetic variants that influence MetS risk were selected by genome-wide association study after adjusting for age, sex, area of residence and BMI in 8840 middle-aged adults. GRS were calculated by summing the risk alleles of the selected SNP and divided into low (0-1), medium (2-3) and high (4-7) risk groups, and the relationships between the MetS and GRS were determined by logistic regression after adjusting covariates involved in MetS risk. We also analysed the interaction between GRS and lifestyles. Four genetic variants (APOA5_rs651821, EFCAB4B_rs4766165, ZNF259_rs2160669 and APOBEC1_rs10845640) were selected because they increased MetS risk after adjusting for covariates. Individuals with medium-GRS and high-GRS alleles had a higher MetS risk by 1·48- and 2·23-fold, respectively, compared with those with low-GRS after adjusting for covariates. The increase in MetS risk was mainly related to serum TAG and HDL-cholesterol concentrations. The GRS had an interaction with carbohydrate (CHO) and Na intakes and daily physical activities for MetS risk. In conclusion, Asian middle-aged adults with high-GRS alleles were at increased MetS risk mainly due to dyslipidaemia. High daily physical activity (≥1 h moderate activity per d) reduced the MetS risk but a low-CHO diet (<65 % of total energy intake) increased the risk in carriers with high-GRS alleles. Low Na intake (<1·6 g Na intake/4 MJ) did not decrease its risk.

Raw Bowl Tea (Tuocha) Polyphenol Prevention of Nonalcoholic Fatty Liver Disease by Regulating Intestinal Function in Mice

A high-fat diet-induced C57BL/6N mouse model of non-alcoholic fatty liver disease (NAFLD) was established. The effect and mechanism of Raw Bowl Tea polyphenols (RBTP) on preventing NAFLD via regulating intestinal function were observed. The serum, liver, epididymis, small intestine tissues, and feces of mice were examined by biochemical and molecular biological methods, and the composition of RBTP was analyzed by HPLC assay. The results showed that RBTP could effectively reduce the body weight, liver weight, and liver index of NAFLD mice. The serum effects of RBTP were: (1) decreases in alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (AKP), total cholesterol (TC), triglyceride (TG), low density lipoprotein cholesterol (LDL-C), D-lactate (D-LA), diamine oxidase (DAO), lipopolysaccharide (LPS), and an increase of high density lipoprotein cholesterol (HDL-C) levels; (2) a decrease of inflammatory cytokines such as interleukin 1 beta (IL-1β), interleukin 4 (IL-4), interleukin 6 (IL-6), interleukin 10 (IL-10), tumor necrosis factor alpha (TNF-α), and interferon gamma (INF-γ); (3) a decrease the reactive oxygen species (ROS) level in liver tissue; and (4) alleviation of pathological injuries of liver, epididymis, and small intestinal tissues caused by NAFLD and protection of body tissues. qPCR and Western blot results showed that RBTP could up-regulate the mRNA and protein expressions of LPL, PPAR-α, CYP7A1, and CPT1, and down-regulate PPAR-γ and C/EBP-α in the liver of NAFLD mice. In addition, RBTP up-regulated the expression of occludin and ZO-1, and down-regulated the expression of CD36 and TNF-α in the small intestines of NAFLD mice. Studies on mice feces showed that RBTP reduced the level of Firmicutes and increased the minimum levels of Bacteroides and Akkermansia, as well as reduced the proportion of Firmicutes/Bacteroides in the feces of NAFLD mice, which play a role in regulating intestinal microecology. Component analysis showed that RBTP contained seven polyphenolic compounds: Gallic acid, (-)-epigallocatechin, catechin, L-epicatechin, (-)-epigallocatechin gallate, (-)-gallocatechin gallate, and (-)-epicatechin gallate (ECG), and high levels of caffeine, (-)-epigallocatechin (EGC), and ECG. RBTP improved the intestinal environment of NAFLD mice with the contained active ingredients, thus playing a role in preventing NAFLD. The effect was positively correlated with the dose of 100 mg/kg, which was even better than that of the clinical drug bezafibrate.

The Inhibitory Effect of Cordycepin on the Proliferation of MCF-7 Breast Cancer Cells, and its Mechanism: An Investigation Using Network Pharmacology-Based Analysis

Cordyceps militaris is a well-known medicinal mushroom. It is non-toxic and has clinical health benefits including cancer inhibition. However, the anticancer effects of C. militaris cultured in brown rice on breast cancer have not yet been reported. In this study, we simultaneously investigated the anticancer effects of cordycepin and an extract of C. militaris cultured in brown rice on MCF-7 human breast cancer cells using a cell viability assay, cell staining with Hoechst 33342, and an image-based cytometric assay. The C. militaris concentrate exhibited significant MCF-7 cell inhibitory effects, and its IC₅₀ value was 73.48 µg/mL. Cordycepin also exhibited significant MCF-7 cell inhibitory effects, and its IC₅₀ value was 9.58 µM. We applied network pharmacological analysis to predict potential targets and pathways of cordycepin. The gene set enrichment analysis showed that the targets of cordycepin are mainly associated with the hedgehog signaling, apoptosis, p53 signaling, and estrogen signaling pathways. We further verified the predicted targets related to the apoptosis pathway using western blot analysis. The C. militaris concentrate and cordycepin exhibited the ability to induce apoptotic cell death by increasing the cleavage of caspase-7 -8, and -9, increasing the Bax/Bcl-2 protein expression ratio, and decreasing the protein expression of XIAP in MCF-7 cells. Consequently, the C. militaris concentrate and cordycepin exhibited significant anticancer effects through their ability to induce apoptosis in breast cancer cells.

Fibroblast growth factor 21 in lipid metabolism and non-alcoholic fatty liver disease

Non-alcoholic fatty liver disease (NAFLD) is one of the most common liver diseases in several developed countries, ranging from simple non-alcoholic fatty liver (NAFL) to non-alcoholic steatohepatitis (NASH) and cirrhosis. Currently, NAFLD has been confirmed to be associated with dyslipidemia, insulin resistance, and pre-diabetes, which are always grouped together as metabolic syndrome. Fibroblast growth factor 21 (FGF21) plays an important role in liver pathophysiology with multiple metabolic functions. Accumulating evidence has shown that FGF21 could directly modulate lipid metabolism and reduce lipid accumulation in hepatocytes through an insulin-independent pathway, thus suppressing the pathogenesis of NAFLD. Furthermore, treatment with FGF21 could obviously reverse NAFLD and synergistically alleviate obesity and counteract insulin resistance. In this review, we summarize the current knowledge of FGF21 and the evidence of FGF21 as an important regulator in hepatic lipid metabolism. The mechanisms by which FGF21 affects the pathogenesis of NAFLD would also be proposed for the further understanding of FGF21.

Anti-Obesity Effects of Lactobacillus fermentum CQPC05 Isolated from Sichuan Pickle in High-Fat Diet-Induced Obese Mice through PPAR-α Signaling Pathway

Sichuan pickle is a traditional fermented food in China which is produced by the spontaneous fermentation of Chinese cabbage. In this study, the anti-obesity effects of a new lactic acid bacterium (Lactobacillus fermentum CQPC05, LF-CQPC05) isolated from Sichuan pickles were assessed in vivo. An obese animal model was established in mice by inducing obesity with high-fat diet. Both serum and tissues were collected from the mice, and then subjected to qPCR and Western blot analyses. The results showed that LF-CQPC05 could decrease the values of hepatosomatic, epididymal fat, and perirenal fat indices that were induced by a high-fat diet in mice. Moreover, LF-CQPC05 reduced the levels of alanine aminotransferase (ALT), aspartate aminotransaminase (AST), total cholesterol (TC), triglyceride (TG), and low-density lipoprotein cholesterol (LDL-C), and increased the level of high-density lipoprotein cholesterol (HDL-C) in both serum samples and liver tissues of obese mice fed with a high-fat diet. Pathological observations demonstrated that LF-CQPC05 could alleviate the obesity-induced pathological changes in the liver tissue of mice, and reduce the degree of adipocyte enlargement. The results of qPCR and Western blot analyses further indicated that LF-CQPC05 upregulated the mRNA and protein expression levels of lipoprotein lipase (LPL), PPAR-α: peroxisome proliferator-activated receptor-alpha (PPAR-α), (cholesterol 7 alpha-hydroxylase) CYP7A1, and carnitine palmitoyltransferase 1 (CPT1A), and downregulated the expression levels of peroxisome proliferator-activated receptor-gamma (PPAR-γ) and CCAAT enhancer-binding protein alpha (C/EBP-α) in both liver tissue and epididymal adipose tissue. Taken altogether, this study reveals that LF-CQPC05 can effectively inhibit high-fat diet-induced obesity. Its anti-obesity effect is comparable to that of l-carnitine, and is superior to that of Lactobacillus delbrueckii subsp. bulgaricus, a common strain used in the dairy industry. Therefore, LF-CQPC05 is a high-quality microbial strain with probiotic potential.

Species differences in lipoprotein lipase and hepatic lipase activities: comparative studies of animal models of lifestyle-related diseases

Lipoprotein lipase (LPL) and hepatic triglyceride lipase (HTGL) have an important role in lifestyle-related diseases. To evaluate species differences, we compared LPL and HTGL activities in different animal models of lifestyle-related diseases using the same assay kit. Normal animals (JW rabbits, ICR mice, and SD rats), a hypercholesterolemic animal model (WHHLMI rabbits), and obese animal models (KK-A^y mice and Zucker fatty rats) fed standard chow were used in this study. Plasma was prepared before and after an intravenous injection of heparin sodium under fasting and feeding. LPL and HTGL activities were measured with the LPL/HTGL activity assay kit (Immuno-Biological Laboratories) using an auto-analyzer. Only in mice, high HTGL activity was observed in pre-heparin plasma. In normal animals, LPL and HTGL activities were high in ICR mice and SD rats but low in JW rabbits. Compared to normal animals, LPL activity was high in Zucker fatty rats and WHHLMI rabbits at both fasting and feeding, while LPL activity after feeding was low in KK-A^y mice. HTGL activity was higher in fasted and fed WHHLMI rabbits and fasted Zucker fatty rats, but was lower in fed KK-A^y mice. Gender difference was observed in HTGL activity in SD rats and LPL activity in WHHLMI rabbits but not in ICR mice. In conclusion, this simple assay method was effective for measuring LPL and HTGL activities of experimental animals, and the activities are highly regulated depending on animal species, animal models, feeding/fasting conditions and genders.

Vitamin E Metabolic Effects and Genetic Variants: A Challenge for Precision Nutrition in Obesity and Associated Disturbances

Vitamin E (VE) has a recognized leading role as a contributor to the protection of cell constituents from oxidative damage. However, evidence suggests that the health benefits of VE go far beyond that of an antioxidant acting in lipophilic environments. In humans, VE is channeled toward pathways dealing with lipoproteins and cholesterol, underlining its relevance in lipid handling and metabolism. In this context, both VE intake and status may be relevant in physiopathological conditions associated with disturbances in lipid metabolism or concomitant with oxidative stress, such as obesity. However, dietary reference values for VE in obese populations have not yet been defined, and VE supplementation trials show contradictory results. Therefore, a better understanding of the role of genetic variants in genes involved in VE metabolism may be crucial to exert dietary recommendations with a higher degree of precision. In particular, genetic variability should be taken into account in targets concerning VE bioavailability per se or concomitant with impaired lipoprotein transport. Genetic variants associated with impaired VE liver balance, and the handling/resolution of oxidative stress might also be relevant, but the core information that exists at present is insufficient to deliver precise recommendations.