Regulatory T cells control Effector T cell Inflammation in Human Prediabetes

A disparate array of plasma/serum markers provide evidence for chronic inflammation in human prediabetes, a condition that is most closely replicated by standard mouse models of obesity and meta-flammation. These remain largely non-actionable, and contrast with our rich understanding of inflammation in human type 2 diabetes. New data show that<b> </b>inflammatory profiles produced by CD4⁺ T cells define human prediabetes as a unique inflammatory state. Regulatory T cells (Tregs) control mitochondrial function and cytokine production by CD4⁺ effector T cells (Teff) in prediabetes and type 2 diabetes by supporting Th17 or Th1 cytokine production, respectively. These data suggest that Treg control of Teff metabolism controls inflammation differentially in prediabetes compared to type 2 diabetes. Queries of genes that impact mitochondrial function and/or pathways leading to transcription of lipid metabolism genes identified the fatty acid importer CD36 as highly expressed in Tregs but not Teff from prediabetes subjects. Pharmacological blockade of CD36 in Tregs from prediabetes subjects decreased Teff production of the Th17 cytokines that differentiate overall prediabetes inflammation. We conclude Tregs control CD4⁺ T cell cytokine profiles through mechanisms determined, at least in part, by host metabolic status. Furthermore, Treg CD36 uniquely promotes Th17 cytokine production by Teff in prediabetes.

Analysis of differential expression of lipid metabolism genes in atherosclerotic plaques in patients with coronary atherosclerosis

Aim. The goal of the study was to analyze the differential expression of lipid metabolism-related genes in the atherosclerotic plaques of different types in patients with coronary atherosclerosis.Material and Methods. The study was performed on the specimens of atherosclerotic plaques in 45–65-year-old patients with coronary atherosclerosis with stable exertional angina functional class II-IV without acute coronary syndrome. Coronary atherosclerosis was verified by coronary angiography. Atherosclerotic plaque tissue was sampled intraoperatively when indicated. Whole-genome sequencing of ribonucleic acid (RNA) was performed using the TruSeq RNA Sample Preparation Kit (Illumina, USA).Results. We analyzed the differences in the expression of 12 genes including LDLR, APOB, PCSK9, LDLRAP1, LIPA, STAP1, ABCA1, APOA1, APOE, LPL, SCARB1, and SREBF2 depending on the type of atherosclerotic plaques. The expression level of APOE gene was eight times higher in unstable atherosclerotic plaques of dystrophic-necrotic type (p < 0.0001). The expression levels of LDLR and APOB genes were eight times higher in stable atherosclerotic plaques (p < 0.0001). We did not find differences in the expression levels of the ABCG5, ABCG8, APOC3, CETP, CLPS, CYP7A1, and PNPLA5 genes.Conclusion. The study showed the differences in the activity of individual metabolism-related genes in the atherosclerotic plaques of different types in patients with coronary atherosclerosis. Obtained data may become the basis for the development of test systems aimed at predicting the development of atherosclerotic process and its complications.

An integrated omics analysis reveals the gene expression profiles of rapeseed, castor bean, and maize for seed oil biosynthesis

Background Seed storage lipids are valuable for human diet and for the sustainable development of mankind. In recent decades, many lipid metabolism genes and pathways have been identified, but the molecular mechanisms that underlie species differences in seed oil biosynthesis are not fully understood. Results To investigate the molecular mechanisms of seed oil accumulation in different species, we performed comparative genome and transcriptome analyses of rapeseed and castor bean, which have high seed oil contents, and maize, which has a low seed oil content. The results uncovered the molecular mechanism of the low and high seed oil content in maize and castor bean, respectively. Transcriptome analyses showed that more than 61% of the lipid- and carbohydrate-related genes were regulated in rapeseed and castor bean, but only 20.1% of the lipid-related genes and 22.5% of the carbohydrate-related genes were regulated in maize. Compared to rapeseed and castor bean, fewer lipid biosynthesis genes but more lipid metabolism genes were regulated in the maize embryo. More importantly, most maize genes encoding lipid-related transcription factors, triacylglycerol (TAG) biosynthetic enzymes, pentose phosphate pathway (PPP) and Calvin Cycle proteins were not regulated during seed oil synthesis, despite the presence of many homologs in the maize genome. These results revealed the molecular underpinnings of the low seed oil content in maize. In castor bean, we observed differential regulation of vital oil biosynthetic enzymes and extremely high expression levels of oil biosynthetic genes, which were consistent with the rapid accumulation of oil in castor bean developing seeds. Conclusions Compared to oil seed (rapeseed and castor bean), less oil biosynthetic genes were regulated during the seed development in non-oil seed (maize). These results shed light on molecular mechanisms of lipid biosynthesis in rapeseed, castor bean, and maize. They can provide information on key target genes that may be useful for future experimental manipulation of oil production in oilseed crops.

Analysis of Rare Variants in Genes Related to Lipid Metabolism in Patients with Familial Hypercholesterolemia in Western Siberia (Russia)

The aim of this work was to identify genetic variants potentially involved in familial hypercholesterolemia in 43 genes associated with lipid metabolism disorders. Targeted high-throughput sequencing of lipid metabolism genes was performed (80 subjects with a familial-hypercholesterolemia phenotype). For patients without functionally significant substitutions in the above genes, multiplex ligation-dependent probe amplification was conducted to determine bigger mutations (deletions and/or duplications) in the LDLR promoter and exons. A clinically significant variant in some gene associated with familial hypercholesterolemia was identified in 47.5% of the subjects. Clinically significant variants in the LDLR gene were identified in 19 probands (73.1% of all variants identified in probands); in three probands (11.5%), pathogenic variants were found in the APOB gene; and in four probands (15.4%), rare, clinically significant variants were identified in genes LPL, SREBF1, APOC3, and ABCG5. In 12 (85.7%) of 14 children of the probands, clinically significant variants were detectable in genes associated with familial hypercholesterolemia. The use of clinical criteria, targeted sequencing, and multiplex ligation-dependent probe amplification makes it possible to identify carriers of rare clinically significant variants in a wide range of lipid metabolism genes and to investigate their influence on phenotypic manifestations of familial hypercholesterolemia.

Polymorphisms in Genes of Lipid Metabolism Are Associated with Type 2 Diabetes Mellitus and Periodontitis, as Comorbidities, and with the Subjects’ Periodontal, Glycemic, and Lipid Profiles

Background. Type 2 diabetes mellitus (T2DM) and periodontitis (P) commonly occur as comorbidities, but the commonalities in the genetic makeup of affected individuals is largely unknown. Since dyslipidemia is a frequent condition in these individuals, we investigate the association of genomic variations in genes involved in lipid metabolism with periodontal, glycemic, lipid profiles, and the association with periodontitis and T2DM (as comorbidities). Methods. Based on clinical periodontal examination and biochemical evaluation, 893 subjects were divided into T2DM+P (T2DM subjects also affected by periodontitis, n = 205 ), periodontitis ( n = 345 ), and healthy ( n = 343 ). Fourteen single-nucleotide polymorphisms (SNPs) were investigated: LDLR gene (rs5925 and rs688), APOB (rs676210, rs1042031, and rs693), ABCC8 (rs6544718 and 6544713), LPL (rs28524, rs3735964, and rs1370225), HNF1A (rs2650000), APOE (rs429358 and rs7412), and HNF4A (rs1800961). Multiple linear and logistic regressions (adjusted for covariates) were made for all populations and stratified by sex and smoking habits. Results. Individuals carrying APOB-rs1042031-CT (mainly women and never smokers) had a lower risk of developing periodontitis and T2DM (T2DM+P); altogether, this genotype was related with healthier glycemic, lipid, and periodontal parameters. Significant disease-phenotype associations with gene-sex interaction were also found for carriers of APOB-rs1676210-AG, HNF4A-rs1800961-CT, ABCC8-rs6544718-CT, LPL-rs13702-CC, and LPL-rs285-CT. Conclusions. Polymorphisms in lipid metabolism genes are associated with susceptibility to T2DM-periodontitis comorbidities, demonstrating gene-sex interaction. The APOB-rs1042031 was the most relevant gene marker related to glucose and lipid metabolism profiles, as well as with obesity and periodontitis.

TAMI-75. LIPID METABOLISM AS A THERAPEUTIC VULNERABILITY IN BET INHIBITOR-RESISTANT MEDULLOBLASTOMA

MYC-driven medulloblastomas are a particularly devastating group of pediatric brain tumors that exhibit resistance and continued progression despite standard of care treatments. Our preclinical work identified BET-bromodomain inhibitors as a potentially promising new class of drugs for children with medulloblastoma and other MYC-driven cancers, providing rationale to evaluate these agents in clinical trials. However, treatment with BET inhibitor (BETi) alone is unlikely to be sufficient for a cure, with most tumors evolving to acquire resistance to single-agent targeted therapies. We applied an integrative genomics approach to identify genes and pathways mediating BETi response in medulloblastoma. These studies revealed that MYC-driven medulloblastoma cells with acquired resistance to BETi reinstate transcription of essential genes suppressed by drug, and exhibit changes in cell state and new vulnerabilities not present in drug-sensitive cells. We now have a growing body of evidence showing that BET inhibition downregulates the expression of key lipid metabolism genes and metabolism-related signaling pathways, and that medulloblastoma cells with adaptive resistance to drug differentially express and exhibit preferential dependency on specific lipid metabolic genes and transcriptional regulators. Our studies explore the possibility of exploiting these novel metabolic vulnerabilities in order to overcome BETi resistance and provide a more efficacious upfront therapy.

Haplotype analysis of polymorphic genes of lipid metabolism and its association with an increased risk of the first non-cardioembolic ischemic stroke

Aim We studied the effect of haplotype variations in lipid metabolism genes on the risk of first non-cardioembolic ischemic stroke in 206 patients and 206 controls. Material and methods The alleles frequencies and genotypes assessed for 5 mono-nucleotide polymorphic gene variants (APOB (rs1042031), APOEB (rs676210), APOC-IV (rs1132899), APOE (rs 7412), APOE (rs 429358), LP(a) (rs41267817)) in 206 patients, who had first non-cardioembolic ischemic stroke, and 206 persons with no stroke, comparable with age, gender, place of living and ethnicity. Genotyping of polymorphisms was done with the prepared TaqMan probes. Haplotype analysis was performed using the online tool SNPStat. Results Haplotype analysis revealed that CTGATT, CTGACT and CCAGTT, haplotypes of lipid metabolism genes polymorphisms are associated with risk of first non-cardioembolic ischemic stroke after multivariate adjustment. Conclusions These results show that haplotype of lipid metabolism genes polymorphisms are signifcantly associated with increased the development of the first non-cardioembolic ischemic stroke In the studied groups. FUNDunding Acknowledgement Type of funding sources: None.

Next Generation Sequencing of Single Nucleotide Polymorphic DNA-Markers in Selecting for Intramuscular Fat, Fat Melting Point, Omega-3 Long-Chain Polyunsaturated Fatty Acids and Meat Eating Quality in Tattykeel Australian White MARGRA Lamb

Meat quality data can only be obtained after slaughter when selection decisions about the live animal are already too late. Carcass estimated breeding values present major precision problems due to low accuracy, and by the time an informed decision on the genetic merit for meat quality is made, the animal is already dead. We report for the first time, a targeted next-generation sequencing (NGS) of single nucleotide polymorphisms (SNP) of lipid metabolism genes in Tattykeel Australian White (TAW) sheep of the MARGRA lamb brand, utilizing an innovative and minimally invasive muscle biopsy sampling technique for directly quantifying the genetic worth of live lambs for health-beneficial omega-3 long-chain polyunsaturated fatty acids (n-3 LC-PUFA), intramuscular fat (IMF), and fat melting point (FMP). NGS of stearoyl-CoA desaturase (SCD), fatty acid binding protein-4 (FABP4), and fatty acid synthase (FASN) genes identified functional SNP with unique DNA marker signatures for TAW genetics. The SCD g.23881050T>C locus was significantly associated with IMF, C22:6n-3, and C22:5n-3; FASN g.12323864A>G locus with FMP, C18:3n-3, C18:1n-9, C18:0, C16:0, MUFA, and FABP4 g.62829478A>T locus with IMF. These add new knowledge, precision, and reliability in directly making early and informed decisions on live sheep selection and breeding for health-beneficial n-3 LC-PUFA, FMP, IMF and superior meat-eating quality at the farmgate level. The findings provide evidence that significant associations exist between SNP of lipid metabolism genes and n-3 LC-PUFA, IMF, and FMP, thus underpinning potential marker-assisted selection for meat-eating quality traits in TAW lambs.

Pre-Weaning Inulin Supplementation Alters the Ileal Transcriptome in Pigs Regarding Lipid Metabolism

Prebiotics, such as inulin, are non-digestible compounds that stimulate the growth of beneficial microbiota, which results in improved gut and overall health. In this study, we were interested to see if, and how, the ileal transcriptome altered after inulin administration in the pre-weaning period in pigs. Seventy-two Piétrain–Landrace newborn piglets were divided into three groups: (a) a control (CON) group (n = 24), (b) an inulin (IN)-0.5 group (n = 24), and (c) an IN-0.75 group (n = 24). Inulin was provided as a solution and administered twice a day. At week 4, eight piglets per group, those closest to the average in body weight, were sacrificed, and ileal scrapings were collected and analyzed using 3′ mRNA massively parallel sequencing. Only minor differences were found, and three genes were differentially expressed between the CON and IN-0.5 group, at an FDR of 10%. All three genes were downregulated in the IN-0.5 group. When comparing the CON group with the IN-0.75 group, five genes were downregulated in the IN-0.75 group, including the three genes seen earlier as differentially expressed between CON and IN-0.5. No genes were found to be differential expressed between IN-0.5 and IN-0.75. Validation of a selection of these genes was done using qRT-PCR. Among the downregulated genes were Angiopoietin-like protein 4 (ANGPTL4), Aquaporin 7 (AQP7), and Apolipoprotein A1 (APOA1). Thus, although only a few genes were found to be differentially expressed, several of them were involved in lipid metabolism, belonging to the peroxisome proliferator-activated receptor (PPAR) signaling pathway and known to promote lipolysis. We, therefore, conclude that these lipid metabolism genes expressed in the ileum may play an important role when supplementing piglets with inulin early in life, before weaning.

Neurodevelopmental clustering of gene expression identifies lipid metabolism genes associated with neuroprotection and neurodegeneration.

APOE variants present the strongest association with sporadic Alzheimers Disease. APOE is also highly expressed during neurodevelopment in the Central Nervous System (CNS) and has been shown to be neuroprotective in infancy and gestation. We explored other lipid metabolism genes to determine whether they show a similar neurodevelopmental expression trajectory and are associated with neurodegeneration. APOE was by far the most highly expressed of the lipid metabolism genes in the CNS. Two other genes, Apolipoprotein C1 (APOC1) Glutamate-Ammonia Ligase (GLUL, also known as glutamine synthetase), co-clustered with Apolipoprotein E (APOE) in its developmental trajectory in late gestation through early childhood. These three genes highlight brain structures and developmental time-windows distinct from other lipid metabolism genes. In the CNS they are primarily expressed in astrocytes and are implicated in neuroprotection and neurodegeneration.