Serum metabonomics reveal the effectiveness of human placental mesenchymal stem cell therapy for primary sclerosing cholangitis.

BACKGROUND: The metabolic patterns of human placental-derived mesenchymal stem cell (hP-MSC) treatment for primary sclerosing cholangitis (PSC) remain unclear, and therapeutic effects significantly vary due to individual differences. Therefore, it is crucial to investigate the serological response to hP-MSC transplantation through small molecular metabolites and identify easily detectable markers for efficacy evaluation. METHODS: Using Mdr2-/- mice as a PSC model and Mdr2+/+ mice as controls, the efficacy of hP-MSC treatment was assessed based on liver pathology, liver enzymes, and inflammatory factors. Serum samples were collected for 12C-/13C-dansylation and DmPA labeling LC-MS analysis to investigate changes in metabolic pathways after hP-MSC treatment. Key metabolites and regulatory enzymes were validated by qRT-PCR and Western blotting. Potential biomarkers of hP-MSC efficacy were identified through correlation analysis and machine learning. RESULTS: Collectively, the results of the liver histology, serum liver enzyme levels, and inflammatory factors supported the therapeutic efficacy of hP-MSC treatment. Based on significant differences, 41 differentially expressed metabolites were initially identified; these were enriched in bile acid, lipid, and hydroxyproline metabolism. After treatment, bile acid transport was accelerated, whereas bile acid production was reduced; unsaturated fatty acid synthesis was upregulated overall, with increased FADS2 and elongase expression and enhanced fatty acid ß-oxidation; hepatic proline 4-hydroxylase expression was decreased, leading to reduced hydroxyproline production. Correlation analysis of liver enzymes and metabolites, combined with time trends, identified eight potential biomarkers: 2-aminomuconate semialdehyde, L-1-pyrroline-3-hydroxy-5-carboxylic acid, L-isoglutamine, and maleamic acid were more abundant in model mice but decreased after hP-MSC treatment. Conversely, 15-methylpalmitic, eicosenoic, nonadecanoic, and octadecanoic acids were less abundant in model mice but increased after hP-MSC treatment. CONCLUSIONS: This study revealed metabolic regulatory changes in PSC model mice after hP-MSC treatment and identified eight promising biomarkers, providing preclinical evidence to support therapeutic applications of hP-MSC.

Gene therapy for fat-1 prevents obesity-induced metabolic dysfunction, cellular senescence, and osteoarthritis.

Obesity is one of the primary risk factors for osteoarthritis (OA), acting through cross talk among altered biomechanics, metabolism, adipokines, and dietary free fatty acid (FA) composition. Obesity and aging have been linked to cellular senescence in various tissues, resulting in increased local and systemic inflammation and immune dysfunction. We hypothesized that obesity and joint injury lead to cellular senescence that is typically associated with increased OA severity or with aging and that the ratio of omega-6 (ω-6) to omega-3 (ω-3) FAs regulates these pathologic effects. Mice were placed on an ω-6-rich high-fat diet or a lean control diet and underwent destabilization of the medial meniscus to induce OA. Obesity and joint injury significantly increased cellular senescence in subcutaneous and visceral fat as well as joint tissues such as synovium and cartilage. Using adeno-associated virus (AAV) gene therapy for fat-1, a fatty acid desaturase that converts ω-6 to ω-3 FAs, decreasing the serum ω-6:ω-3 FA ratio had a strong senomorphic and therapeutic effect, mitigating metabolic dysfunction, cellular senescence, and joint degeneration. In vitro coculture of bone marrow-derived macrophages and chondrocytes from control and AAV8-fat1-treated mice were used to examine the roles of various FA mediators in regulating chondrocyte senescence. Our results suggest that obesity and joint injury result in a premature "aging" of the joint as measured by senescence markers, and these changes can be ameliorated by altering FA composition using fat-1 gene therapy. These findings support the potential for fat-1 gene therapy to treat obesity- and/or injury-induced OA clinically.

Genetic Features of Lipid and Carbohydrate Metabolism in Arctic Peoples.

Prolonged adaptation of ancestors of indigenous peoples of the Far North of Asia and America to extreme natural and climatic conditions of the Arctic has resulted in changes in genes controlling various metabolic processes. However, most genetic variability observed in the Eskimo and Paleoasians (the Chukchi and Koryaks) is related to adaptation to the traditional Arctic diet, which is rich in lipids and proteins but extremely poor in plant carbohydrates. The results of population genetic studies have demonstrated that specific polymorphic variants in genes related to lipid metabolism (CPT1A, FADS1, FADS2, and CYB5R2) and carbohydrate metabolism (AMY1, AMY2A, and SI) are prevalent in the Eskimo and Paleoasian peoples. When individuals deviate from their traditional dietary patterns, the aforementioned variants of genetic polymorphism can lead to the development of metabolic disorders. American Eskimo-specific variants in genes related to glucose metabolism (TBC1D and ADCY) significantly increase the risk of developing type 2 diabetes. These circumstances indicate the necessity for a large-scale genetic testing of indigenous population of the Far North and the need to study the biochemical and physiological consequences of genetically determined changes in the activity of enzymes of lipid and carbohydrate metabolism.

Identification of genomic regions associated with fatty acid metabolism across blood, liver, backfat and muscle in pigs.

BACKGROUND: The composition and distribution of fatty acids (FA) are important factors determining the quality, flavor, and nutrient value of meat. In addition, FAs synthesized in the body participate in energy metabolism and are involved in different regulatory pathways in the form of signaling molecules or by acting as agonist or antagonist ligands of different nuclear receptors. Finally, synthesis and catabolism of FAs affect adaptive immunity by regulating lymphocyte metabolism. The present study performed genome-wide association studies using FA profiles of blood, liver, backfat and muscle from 432 commercial Duroc pigs. RESULTS: Twenty-five genomic regions located on 15 Sus scrofa chromosomes (SSC) were detected. Annotation of the quantitative trait locus (QTL) regions identified 49 lipid metabolism-related candidate genes. Among these QTLs, four were identified in more than one tissue. The ratio of C20:4n-6/C20:3n-6 was associated with the region on SSC2 at 7.56-14.26 Mb for backfat, liver, and muscle. Members of the fatty acid desaturase gene cluster (FADS1, FADS2, and FADS3) are the most promising candidate genes in this region. Two QTL regions on SSC14 (103.81-115.64 Mb and 100.91-128.14 Mb) were identified for FA desaturation in backfat and muscle. In addition, two separate regions on SSC9 at 0 - 14.55 Mb and on SSC12 at 0-1.91 Mb were both associated with the same multiple FA traits for backfat, with candidate genes involved in de novo FA synthesis and triacylglycerol (TAG) metabolism, such as DGAT2 and FASN. The ratio C20:0/C18:0 was associated with the region on SSC5 at 64.84-78.32 Mb for backfat. Furthermore, the association of the C16:0 content with the region at 118.92-123.95 Mb on SSC4 was blood specific. Finally, candidate genes involved in de novo lipogenesis regulate T cell differentiation and promote the generation of palmitoleate, an adipokine that alleviates inflammation. CONCLUSIONS: Several SNPs and candidate genes were associated with lipid metabolism in blood, liver, backfat, and muscle. These results contribute to elucidating the molecular mechanisms implicated in the determination of the FA profile in different pig tissues and can be useful in selection programs that aim to improve health and energy metabolism in pigs.

Overexpression of PER2 Promotes De Novo Fatty Acid Synthesis, Fatty Acid Desaturation, and Triglyceride Accumulation in Bovine Mammary Epithelial Cells.

The core clock gene Period2 (PER2) is associated with mammary gland development and lipid synthesis in rodents and has recently been found to have a diurnal variation in the process of lactation, but has not yet been demonstrated in bovine mammary epithelial cells (BMECs). To explore the regulatory function of PER2 on milk fat synthesis in bovine mammary epithelial cells, we initially assessed the expression of clock genes and milk fat metabolism genes for 24 h using real-time quantitative PCR and fitted the data to a cosine function curve. Subsequently, we overexpressed the PER2 in BMECs using plasmid vector (pcDNA3.1-PER2), with empty vector pcDNA3.1-myc as the control. After transfecting BMECs for 48 h, we assessed the protein abundance related to milk fat synthesis by Western blot, the expression of genes coding for these proteins using real time-quantitative PCR, the production of triacylglycerol, and the fatty acid profile. The findings indicated that a total of nine clock genes (PER1/2, CRY1/2, REV-ERBα, BMAL1, NCOR1, NR2F2, FBXW11), seven fatty acid metabolism genes (CD36, ACSS2, ACACA, SCD, FADS1, DGAT1, ADFP), and six nuclear receptor-related genes (INSIG1, SCAP, SREBF1, C/EBP, PPARG, LXR) exhibited oscillation with a period close to 24 h in non-transfected BMECs (R2 ≥ 0.7). Compared to the control group (transfected with empty pcDNA3.1-myc), the triglyceride content significantly increased in the PER2 overexpression group (p < 0.05). The lipogenic genes for fatty acid transport and triglyceride synthesis (ACACA, SCD, LPIN1, DGAT1, and SREBF1) were upregulated after PER2 overexpression, along with the upregulation of related protein abundance (p < 0.05). The contents and ratios of palmitic acid (C16:0), oleic acid (C18:1n9c), and trans-oleic acid (C18:1n9t) were significantly increased in the overexpression group (p < 0.05). Overall, the data supported that PER2 participated in the process of milk fat metabolism and is potentially involved in the de novo synthesis and desaturation of fatty acid in bovine mammary epithelial cells.

Utility of Arabidopsis KASII Promoter in Development of an Effective CRISPR/Cas9 System for Soybean Genome Editing and Its Application in Engineering of Soybean Seeds Producing Super-High Oleic and Low Saturated Oils.

This study reports the use of the Arabidopsis KASII promoter (AtKASII) to develop an efficient CRISPR/Cas9 system for soybean genome editing. When this promoter was paired with Arabidopsis U6 promoters to drive Cas9 and single guide RNA expression, respectively, simultaneous editing of the three fatty acid desaturase genes GmFAD2-1A, GmFAD2-1B, and GmFAD3A occurred in more than 60% of transgenic soybean lines at T2 generation, and all the triple mutants possessed desirable high-oleic traits. In sharp contrast, not a single line underwent simultaneous editing of the three target genes when AtKASII was replaced by the widely used AtEC1.2 promoter. Furthermore, our study showed that the stable and inheritable mutations in the high-oleic lines did not alter the overall contents of oil and protein or amino acid composition while increasing the oleic acid content up to 87.6% from approximately 23.8% for wild-type seeds, concomitant with 34.4- and 3.7-fold reductions in linoleic and linolenic acid, respectively. Collectively, this study demonstrates that the AtKASII promoter is highly promising for optimization of the CRISPR/Cas9 system for genome editing in soybean and possibly beyond.

Redesigning soybean with improved oil and meal traits.

KEY MESSAGE: Soybean seed oil and meal composition traits can be combined without interference to provide additional value to the crop. Soybean [Glycine max (L.) Merr.] is an important crop worldwide; its overall value comes from seed oil and high protein meal. The development of soybean varieties with allele combinations for improved oil and meal quality is expected to provide a compositional value bundle for soybean. The high oleic and low linolenic acid seed oil trait (HOLL; > 70% oleic and < 3% linolenic acid) is targeted to optimize the health and functional properties of soybean oil. For soybean meal, metabolizable energy is improved by altering the carbohydrate profile with increased sucrose and decreased anti-nutritional factors, raffinose family of oligosaccharides (RFOs). Previous research identified four variant alleles of fatty acid desaturase (FAD) genes and two raffinose synthase (RS) genes necessary for the HOLL trait in soybean oil and Low or Ultra-Low (UL) RFO traits in soybean meal, respectively. We employed a molecular marker-assisted breeding approach to combine six alleles conferring the desired soybean oil and meal value traits. Eight environment field trials were conducted with twenty-four soybean lines to evaluate phenotypic interactions among the variant alleles of FAD and RS genes. The results indicated that the four FAD gene alleles conditioned the HOLL fatty acid profile of the seed oil regardless of the allele status of the RS genes. Independent of the allele combination of the FAD genes, soybean with two variant alleles of the RS genes had the desired RFO trait in the seeds. The results confirm the feasibility of soybean variety development with this unique combination of oil and meal traits.

Small molecule inhibitors of fungal Δ(9) fatty acid desaturase as antifungal agents against Candida auris.

Candida auris has emerged as a significant healthcare-associated pathogen due to its multidrug-resistant nature. Ongoing constraints in the discovery and provision of new antifungals create an urgent imperative to design effective remedies to this pressing global blight. Herein, we screened a chemical library and identified aryl-carbohydrazide analogs with potent activity against both C. auris and the most prevalent human fungal pathogen, C. albicans. SPB00525 [N'-(2,6-dichlorophenyl)-5-nitro-furan-2-carbohydrazide] exhibited potent activity against different strains that were resistant to standard antifungals. Using drug-induced haploinsufficient profiling, transcriptomics and metabolomic analysis, we uncovered that Ole1, a Δ(9) fatty acid desaturase, is the likely target of SPB00525. An analog of the latter, HTS06170 [N'-(2,6-dichlorophenyl)-4-methyl-1,2,3-thiadiazole-5-carbohydrazide], had a superior antifungal activity against both C. auris and C. albicans. Both SPB00525 and HTS06170 act as antivirulence agents and inhibited the invasive hyphal growth and biofilm formation of C. albicans. SPB00525 and HTS06170 attenuated fungal damage to human enterocytes and ameliorate the survival of Galleria mellonella larvae used as systemic candidiasis model. These data suggest that inhibiting fungal Δ(9) fatty acid desaturase activity represents a potential therapeutic approach for treating fungal infection caused by the superbug C. auris and the most prevalent human fungal pathogen, C. albicans.

Thermal Adaptations in Animals: Genes, Development, and Evolution.

Thermal adaptation to environmental temperature is a driving force in animal evolution. This chapter presents thermal adaptation in ectotherms and endotherms from the perspective of developmental biology. In ectotherms, there are known examples of temperature influencing morphological characteristics, such as seasonal color change, melanization, and sex determination. Furthermore, the timing of embryonic development also varies with environmental temperature. This review will introduce the cellular and molecular mechanisms underlying temperature-dependent embryogenesis. The evolution of thermal adaptation in endotherms is also important for survival in cold climates. Recent genome-wide studies have revealed adaptive mutations in the genomes of extant humans as well as extinct species such as woolly mammoths and Neanderthals. These studies have shown that single-nucleotide polymorphisms in physiologically related genes (e.g., CPT1A, LRP5, THATA, PRKG1, and FADS1-3) allow humans to live in cold climates. At the end of this chapter, we present the remaining questions in terms of genetic assimilation, heat shock protein Hsp90, and embryonic development.

Dissection of the synthesis of polyunsaturated fatty acids in nematodes and Collembola of the soil fauna.

It is becoming increasingly clear that not only unicellular, photoautotrophic eukaryotes, plants, and fungi, but also invertebrates are capable of synthesizing ω3 long-chain polyunsaturated fatty acids (LC-PUFA) de novo. However, the distribution of this anabolic capacity among different invertebrate groups and its implementation at the gene and protein level are often still unknown. This study investigated the PUFA pathways in common soil fauna, i.e. two nematode and two Collembola species. Of these, one species each (Panagrellus redivivus, Folsomia candida) was assumed to produce ω3 LC-PUFA de novo, while the others (Acrobeloides bodenheimeri, Isotoma caerulea) were supposed to be unable to do so. A highly labeled oleic acid (99 % 13C) was supplemented and the isotopic signal was used to trace its metabolic path. All species followed the main pathway of lipid biosynthesis. However, in A. bodenheimeri this terminated at arachidonic acid (ω6 PUFA), whereas the other three species continued the pathway to eicosapentaenoic acid (ω3 PUFA), including I. caerulea. For the nematode P. redivivus the identification and functional characterization of four new fatty acid desaturase (FAD) genes was performed. These genes encode the FAD activities Δ9, Δ6, and Δ5, respectively. Additionally, the Δ12 desaturase was analyzed, yet the observed activity of an ω3 FAD could not be attributed to a coding gene. In the Collembola F. candida, 11 potential first desaturases (Δ9) and 13 front-end desaturases (Δ6 or Δ5 FADs) have been found. Further sequence analysis indicates the presence of omega FADs, specifically Δ12, which are likely derived from Δ9 FADs.

Salix matsudana fatty acid desaturases: Identification, classification, evolution, and expression profiles for development and stress tolerances.

Fatty acid desaturases (FADs) are enzymes that transform carbon­carbon single bonds into carbon­carbon double bonds within acyl chains, resulting in the production of unsaturated FAs (UFAs). They are crucial for plant growth, development, and adaptation to environmental stress. In our research, we identified 40 FAD candidates in the Salix matsudana genome, grouping them into seven categories. Exon-intron structures and conserved motifs of SmFADs within the same group showed significant conservation. Cis-element analysis revealed SmFADs are responsive to hormones and stress. Additionally, GO and KEGG analyses linked SmFADs closely with lipid biosynthesis and UFA biosynthesis, which were crucial for the plant's response to environmental stresses. Notably, the SmFAB2.4, SmADS1, SmFAD7.5, and SmFAD8.2 were predicted to participate in submergence tolerance, whereas SmFAD8.1 and SmFAD7.1 played an essential role in salt stress response. The diverse expression profiles of SmFADs across willow varieties, in various tissues, and throughout the willow bud development stages revealed a spectrum of functional diversity for these genes. Moreover, specific SmFADs might play a crucial role in callus development and the response to culturing conditions in various willow cultivars. This research underscored the importance of SmFAD profiles and functions and identified potential genes for enhancing forest resilience.

CXCR4 influences PUFA desaturation and oxidative stress injury in experimental prostatitis mice by activating Fads2 via PPARγ.

Chronic prostatitis-induced excessive inflammation and oxidative stress (OS) damage substantially affect men's quality of life. However, its treatment remains a major clinical challenge. Therefore, the identification of drugs that can decrease chronic prostatitis and oxidative stress targets is urgent and essential. CXCR4 is a classic chemokine receptor that is crucially associated with the occurrence and development of inflammation. This investigation aimed to elucidate how CXCR4 affects prostatitis regression and progression. The effect of CXCR4 on chronic prostatitis was evaluated by HE staining, immunohistochemistry, immunofluorescence, PCR, and TUNEL analyses. Furthermore, CXCR4 influence on metabolism was also evaluated by monitoring body weight, body temperature, food intake, and LC/MS. Additionally, chromatin immunoprecipitation, Western blot, and double luciferase reporter gene assays were carried out to elucidate the mechanism by which CXCR4 modulates Fads2 transcription by PPARγ. Lastly, ROS, DHE, mito-tracker, and ATP were utilized to validate the α-linolenic acid's protective effect against OS in prostate epithelial cells. It was revealed that the inhibition of CXCR4 can effectively alleviate prostatitis in mice. Furthermore, downregulating CXCR4 expression can markedly reduce the inflammatory cell infiltration in mouse prostates, decrease the elevated levels of DNA damage markers,MDA and 4-HNE, and mitigate apoptosis of prostatic epithelial cells. Moreover, treatment of CXCR4 knockdown mice with a PPARγ inhibitor revealed different degrees of changes in the above phenotypes. Mechanistically, the PPARγ protein translocates to the nucleus and serves as a transcription factor to regulate Fads2 expression, thereby altering PUFA metabolism. Additionally, in vitro experiments indicated that α-linolenic acid can effectively alleviate OS damage and RWPE-1 cell apoptosis by protecting mitochondrial function and enhancing the antioxidant capacity of prostatic epithelial cells. In conclusion, reducing the levels of CXCR4 can alleviate inflammation and OS damage in chronic prostatitis.

Enhancement of Docosahexaenoic Acid and Eicosapentaenoic Acid Biosynthesis in Isochrysis galbana by Bacillus jeotgali.

Isochrysis galbana is valuable in aquaculture due to its production of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). However, achieving high yields of polyunsaturated fatty acids (PUFAs) presents challenges, leading to exploration of innovative approaches. This study investigated the influence of Bacillus jeotgali on the growth of I. galbana and its fatty acid composition. Co-culturing I. galbana with B. jeotgali significantly increased chlorophyll a content and cell abundance, particularly at higher bacterial population densities (algae-to-bacteria ratio of 1:10). Physiological and biochemical analyses found elevated soluble protein content in microalgae co-cultured with B. jeotgali, accompanied by decreased superoxide dismutase (SOD) activity. Fatty acid composition analysis demonstrated a distinctive profile in co-cultured I. galbana, characterized by increased PUFAs, especially EPA and DHA. Gene expression analysis indicated an upregulation of desaturase genes (d4FAD, d5FAD, d6FAD, and d8FAD) associated with PUFA synthesis pathway in I. galbana during co-culturing with B. jeotgali. This study advances our understanding of bacteria-microalgae interactions and presents a promising strategy for enhancing the production of DHA and EPA.

Identification of High Linoleic Acid Varieties in Tetraploid perilla through Gamma-ray Irradiation and CRISPR/Cas9.

Perilla [Perilla frutescens (L.) var frutescens] is a traditional oil crop in Asia, recognized for its seeds abundant in α-linolenic acid (18:3), a key omega-3 fatty acid known for its health benefits. Despite the known nutritional value, the reason behind the higher 18:3 content in tetraploid perilla seeds remained unexplored. Gamma irradiation yielded mutants with altered seed fatty acid composition. Among the mutants, DY-46-5 showed a 27% increase in 18:2 due to the 4-bp deletion of PfrFAD3b, and NC-65-12 displayed a 16% increase in 18:2 due to the loss of function of PfrFAD3a through a large deletion. Knocking out both copies of FATTY ACID DESATURASE3 (PfrFAD3a and PfrFAD3b) simultaneously using CRISPR/Cas9 resulted in an increase in 18:2 by up to 75% and a decrease in 18:3 to as low as 0.3% in seeds, emphasizing the pivotal roles of both genes in 18:3 synthesis in tetraploid perilla. Furthermore, diploid Perilla citriodora, the progenitor of cultivated tetraploid perilla, harbors only PfrFAD3b, with a fatty acid analysis revealing lower 18:3 levels than tetraploid perilla. In conclusion, the enhanced 18:3 content in cultivated tetraploid perilla seeds can be attributed to the acquisition of two FAD3 copies through hybridization with wild-type diploid perilla.

Lipid production from corn straw by cellobiohydrolase and delta-6 desaturase engineered Mucor circinelloides strains under solid state fermentation.

Previously, we constructed engineered M. circinelloides strains that can not only utilize cellulose, but also increase the yield of γ-linolenic acid (GLA). In the present study, an in-depth analysis of lipid accumulation by engineered M. circinelloides strains using corn straw was to be explored. When a two-stage temperature control strategy was adopted with adding 1.5% cellulase and 15% inoculum, the engineered strains led to increases in the lipid yield (up to 1.56 g per 100 g dry medium) and GLA yield (up to 274 mg per 100 g dry medium) of 1.8- and 2.3-fold, respectively, compared with the control strain. This study proved the engineered M. circinelloides strains, especially for Mc-C2PD6, possess advantages in using corn straw to produce GLA. This work provided a reference for transformation from agricultural cellulosic waste to functional lipid in one step, which might play a positive role in promoting the sustainable development of biological industry.

Docosahexaenoic acid insufficiency impairs placental angiogenesis by repressing the methylene-bridge fatty acylation of AKT in preeclampsia.

INTRODUCTION: Preeclampsia (PE), characterised by hypertension in pregnancy, is regarded as a placental metabolism-related syndrome affecting 5-8% of pregnancies worldwide. The insufficiency of polyunsaturated fatty acids (PUFAs), such as docosahexaenoic acid (DHA), is a causative factor of PE pathogenesis. However, its molecular aetiology is yet to be comprehensively elucidated. METHODS: CRISPR/Cas9 was used to construct Fads2 knockout mice. Gas chromatography-mass spectrometry was used to detect placental fatty acid levels. Gene Expression Omnibus was used to analyze placental FADS2 mRNA levels. CCK-8 assay was used to assess cell growth capacity. Cell migration and invasion abilities were measured by transwell and wound healing assay. Tube forming assay was used to test angiogenesis ability. The co-immunoprecipitation assay was used to validate interactions between two proteins. AKT inhibitor MK-2206 and methylene-bridge fatty acylation inhibitor tryptophan were used to rescue experiments. RESULTS: Compared to those in women with normal pregnancies, the DHA levels in the placentas of patients with PE decreased with the downregulation of FADS2, the key desaturase in the synthesis of PUFAs. Pregnant Fads2+/- mice exhibited PE-like symptoms, including proteinuria and elevated systolic arterial blood pressure, due to defective placental angiogenesis. Mechanistically, FADS2 knockdown in trophoblasts decreased cellular DHA levels and repressed the methylene-bridge fatty-acylation of AKT, inhibiting AKT-VEGFA signalling, which is crucial for angiogenesis. DISCUSSION: Our results suggest that placental DHA insufficiency downregulates placental angiogenesis via inhibiting fatty acylating AKT and AKT-VEGFA signalling, a novel insight into abnormal fatty acid metabolism in PE.

Delta-6 desaturase FADS2 is a tumor-promoting factor in cholangiocarcinoma.

Cholangiocarcinoma is a fatal disease with limited therapeutic options. We screened genes required for cholangiocarcinoma tumorigenicity and identified FADS2, a delta-6 desaturase. FADS2 depletion reduced in vivo tumorigenicity and cell proliferation. In clinical samples, FADS2 was expressed in cancer cells but not in stromal cells. FADS2 inhibition also reduced the migration and sphere-forming ability of cells and increased apoptotic cell death and ferroptosis markers. Lipidome assay revealed that triglyceride and cholesterol ester levels were decreased in FADS2-knockdown cells. The oxygen consumption ratio was also decreased in FADS2-depleted cells. These data indicate that FADS2 depletion causes a reduction in lipid levels, resulting in decrease of energy production and attenuation of cancer cell malignancy.

Expression of dihomo-γ-linolenic acid and FADS1/2 and ELOVL2/5 in term rabbit placentas.

Long-chain polyunsaturated fatty acids (LCPUFAs) are essential for both fetal and placental development. We characterized the FA composition and gene expression levels of FA-metabolizing enzymes in rabbit placentas. Total FA compositions from term rabbit placentas (n = 7), livers, and plasma (both n = 4) were examined: among LCPUFAs with more than three double bonds, dihomo-γ-linolenic acid (DGLA) was the most abundant (11.4 ± 0.69 %, mean ± SE), while arachidonic acid was the second-most rich component (6.90 ± 0.56 %). DGLA was barely detectable (<1 %) in livers and plasma from term rabbits, which was significantly lower than in placentas (both p < 0.0001). Compared with the liver, transcript levels of the LCPUFA-metabolizing enzymes FADS2 and ELOVL5 were 7- and 4.5-fold higher in placentas (both p < 0.05), but levels of FADS1 and ELOVL2 were significantly lower (both p < 0.01). Our results suggest a placenta-specific enzyme expression pattern and LCPUFA profile in term rabbits, which may support a healthy pregnancy.

Zeb1 mediates EMT/plasticity-associated ferroptosis sensitivity in cancer cells by regulating lipogenic enzyme expression and phospholipid composition.

Therapy resistance and metastasis, the most fatal steps in cancer, are often triggered by a (partial) activation of the epithelial-mesenchymal transition (EMT) programme. A mesenchymal phenotype predisposes to ferroptosis, a cell death pathway exerted by an iron and oxygen-radical-mediated peroxidation of phospholipids containing polyunsaturated fatty acids. We here show that various forms of EMT activation, including TGFß stimulation and acquired therapy resistance, increase ferroptosis susceptibility in cancer cells, which depends on the EMT transcription factor Zeb1. We demonstrate that Zeb1 increases the ratio of phospholipids containing pro-ferroptotic polyunsaturated fatty acids over cyto-protective monounsaturated fatty acids by modulating the differential expression of the underlying crucial enzymes stearoyl-Co-A desaturase 1 (SCD), fatty acid synthase (FASN), fatty acid desaturase 2 (FADS2), elongation of very long-chain fatty acid 5 (ELOVL5) and long-chain acyl-CoA synthetase 4 (ACSL4). Pharmacological inhibition of selected lipogenic enzymes (SCD and FADS2) allows the manipulation of ferroptosis sensitivity preferentially in high-Zeb1-expressing cancer cells. Our data are of potential translational relevance and suggest a combination of ferroptosis activators and SCD inhibitors for the treatment of aggressive cancers expressing high Zeb1.

PuERF008-PuFAD2 module regulates aroma formation via the fatty acid pathway in response to calcium signaling in 'Nanguo' pear.

Calcium acts as a secondary messenger in plants and is essential for plant growth and development. However, studies on the pathway of aroma synthesis in 'Nanguo' pear (Pyrus ussriensis Maxim.) are scarce. In this study, a bioinformatics analysis of transcriptomic data from calcium-treated 'Nanguo' pear was performed, which identified two fatty acid desaturases, PuFAD2 and PuFAD3, and eight AP2/ERF transcription factors, all exhibiting the same expression patterns. Transient expression experiments showed overexpression of PuFAD2 and PuFAD3 significantly increased the levels of aromatic substrates linoleic acid, hexanal, linolenic acid, and (E)-2-hexenal, but RNAi (RNA interference) had the opposite expression. Promoter sequences analysis revealed that PuFAD2 and PuFAD3 have ERE (estrogen response element) motifs on their promoters. The strongest activation of PuFAD2 by PuERF008 was verified using a dual-luciferase reporting system. Additionally, yeast one-hybrid and electrophoretic mobility shift assays revealed PuERF008 could active PuFAD2. Transient overexpression and RNAi analyses of PuERF008 showed a strong correlation with the expression of PuFAD2. This study provides insights into the process of aroma biosynthesis in 'Nanguo' pear and offers a theoretical basis for elucidating the role of calcium signaling in aroma synthesis.