Search Results (89)

Background: Nonalcoholic fatty liver disease (NAFLD) is common in rheumatoid arthritis (RA), and methotrexate (MTX) use raises concern about hepatotoxicity. We evaluated whether HLA-DRB1, PNPLA3, SLCO1B1, and MTHFR variants are associated with NAFLD, liver fibrosis, or MTX toxicity/pharmacokinetics in RA, after accounting for clinical covariates. Methods: In a cross-sectional cohort of 159 patients with RA, NAFLD, and fibrosis were assessed by FibroScan (CAP ≥ 275 dB/m; LSM > 8 kPa). We compared baseline characteristics by NAFLD status and fitted multivariable models for NAFLD, fibrosis, ALT elevation, and MTX toxicity; MTX pharmacokinetics were analyzed in 111 MTX-treated patients. Multiple testing was controlled using the Benjamini–Hochberg method. Results: The prevalence of NAFLD was 36%, and that of fibrosis was 11%. NAFLD patients had higher CAP and LSM, and markedly greater adiposity indices (body weight, BMI, waist and hip circumference, WC). BMI and WC were independently associated with NAFLD (BMI OR 1.27 per kg/m², 95% CI 1.16–1.40; WC OR 1.06 per cm, 95% CI 1.01–1.12). No HLA-DRB1, PNPLA3, SLCO1B1, or MTHFR variant showed an association that survived multiple-comparison correction. Among MTX users, 21/111 (19%) experienced toxicity. SLCO1B1 and MTHFR variants did not influence MTX pharmacokinetics; age was associated with lower dose-normalized MTX exposure, and cumulative dose was positively associated with exposure. Conclusions: In RA, adiposity—not the tested candidate pharmacogenes—drives NAFLD risk, and SLCO1B1/MTHFR variants do not support MTX dose adjustment. The findings emphasize routine clinical risk factors over single-gene testing for NAFLD and MTX hepatotoxicity in this setting. Full article

Genetics strongly impacts the course of metabolic dysfunction-associated steatotic liver disease (MASLD), with the I148M Patatin like phospholipase domain containing 3 (PNPLA3) variant representing the main modifier. Fat accumulation in the hepatic lobule, strongly enhanced by this SNP, may be influenced by the liver’s zonation. Therefore, we applied spatial transcriptomics to investigate the metabolic processes across portal (PZ)-central (CZ) zones in I148M PNPLA3 carriers. Visium CytAssist technology was applied to liver biopsies from MASLD patients sharing similar disease severity, who were wild-type (WT) or homozygous for the I148M variant (Discovery cohort, n = 4). The distribution of steatosis, inflammation, and fibrosis was assessed in the liver biopsies of MASLD patients, stratified according to the I148M variant (validation cohort, n = 100). At the Visium-LOUPE browser, we spatially mapped PZ and CZ hepatocytes (HEPs), revealing higher lipid turnover, glucose signaling, and lower mitochondrial activity in I148M-PZ-HEPs compared to 148M-CZ-HEPs. Thus, the I148M variant could unbalance the physiological hepatic zonation boosting steatosis development in PZ, consequently inducing mitochondrial dysfunction. The unsupervised analysis confirmed the altered metabolic pattern among CZ and PZ in patients carrying the variant. Interestingly, PNPLA3 expression was higher in I148M-PZ, which also showed an enrichment of non-parenchymal cells, thus possibly explaining the more severe injury in this area. Finally, in the validation cohort, we observed a pronounced PZ distribution of steatosis, inflammation, and fibrosis in I148M PNPLA3 subjects compared to WT, confirming the spatial data. The I148M variant contributes to the metabolic switching across different hepatic zones and represents a new clinical perspective by defining a specific histological pattern of MASLD. Full article

Potato (Solanum tuberosum) is one of the world’s most important food crops, with tuber sink strength and starch deposition determining yield, quality, and processing performance. While starch is the dominant carbohydrate reserve, its accumulation is tightly linked with protein metabolism. Patatin, the major soluble storage protein, constitutes up to 40% of total tuber protein. In addition to serving as a nitrogen and carbon reserve, patatin exhibits lipid acyl hydrolase (phospholipase A₂-like) activity, suggesting roles in membrane remodeling and stress signaling. This dual identity places patatin at the intersection of storage, metabolic regulation, and defense. A structured review of studies published between 1980 and 2025 was developed using PubMed, Web of Science, Frontiers, and MDPI databases. Prioritized research included molecular, physiological, and multi-omics analyses of patatin expression, regulation, and function under optimal and stress conditions. Evidence indicates that patatin contributes to carbon–nitrogen balance and sink strength by affecting sucrose import, vacuolar osmotic capacity, and starch biosynthesis. Under drought, salinity, and pathogen stress, patatin transcript levels, protein stability, and enzymatic activity shift, leading to reduced starch deposition, altered sugar accumulation, osmoprotection, and reallocation toward defense responses. Despite these insights, major knowledge gaps remain. These include isoform-specific roles, integration into sugar–hormone regulatory networks, and field-scale responses under fluctuating environments. Future progress will require integrated multi-omics, fluxomics, and proximity-labeling approaches, combined with CRISPR-based isoform editing and promoter engineering. Targeting patatin as both a biomarker and an engineering node offers opportunities to develop climate-ready potato cultivars with improved starch yield, tuber quality, and stress resilience. Full article

Mutations in the human patatin-like lysophospholipase domain containing the 6 gene PNPLA6 encode an evolutionarily conserved (lyso)phospholipase, leading to the development of a complex hereditary spastic paraplegia 39 (SPG 39) and a number of rare severe syndromes in humans. Diseases disrupt the functioning of the nervous and reproductive systems and the gastrointestinal tract. The study aims to investigate the role of the Drosophila melanogaster swiss cheese gene, an ortholog of the human PNPLA6 gene, in gut function. We showed that the swiss cheese gene knockout leads to changes in the morphology of the midgut, disruption of the septate junction structure and the intestinal barrier permeability, and a decrease in the lipid droplet number in enterocytes. As a result of such disturbances, intestinal stem cells (ISCs) proliferation is activated, and the gut microbiome is altered. Ectopic expression of human PNPLA6 leads to the recovery of the intestinal barrier in the fly gut. The example of Drosophila demonstrates the important role of evolutionarily conserved (lyso)phospholipase in intestinal homeostasis. Full article

Background and Objectives: Patients with GG rs738409 patatin-like phospholipase domain-containing protein 3 (PNPLA3) genotype (148M variant) have greater risk to develop end-stage liver disease and its associated clinical complications, including hepatocellular carcinoma (HCC). We aimed to analyze the association between the PNPLA3 genotype and augmented inflammatory response in transplant candidates with end-stage alcoholic liver disease (ALD). Materials and Methods: Concentrations of 13 cytokines were measured in 106 end-stage ALD patients without HCC (40 with CC, 40 with CG, and 26 with GG genotype), 35 end-stage ALD patients with HCC, and 19 control patients by cytometric bead array. Results: We found significantly higher concentrations of IL-1, IFN-α, IFN-γ, TNF-α, IL-6, CXCL8, IL-10, IL-12, IL-32, and IL-33 in patients with ALD compared to controls, while the concentration of CCL2 was significantly lower. No differences were observed in the concentration of IL-17 and IL-18. ALD patients with and without HCC had similar cytokine concentrations (p > 0.05 for all comparisons). End-stage ALD patients without HCC of the GG genotype had significantly higher CCL2 concentrations (212.6 [135.9–264.9] pg/mL) compared to end-stage ALD patients without HCC carrying the CC/CG genotypes (141.3 [104.1–201.6] pg/mL, p = 0.002, Mann–Whitney). No significant differences across the genotypes were found for the remaining measured cytokines (p > 0.05). GG carriers also had significantly higher levels of AST and ALT, and lower platelet counts. Conclusions: End-stage ALD patients without HCC who carry the PNPLA3 GG genotype have relatively higher CCL2 levels compared to those with the CC or CG genotypes. Relatively elevated CCL2 concentrations in GG patients might contribute to their increased risk of developing clinical complications compared to CC/CG patients. Full article

Previous large-scale genetic studies identified single-nucleotide polymorphisms (SNPs) of the membrane bound O-acyltransferase domain containing 7 (MBOAT7) and patatin-like phospholipase domain containing 3 (PNPLA3) genes as risk factors for metabolic dysfunction-associated steatotic liver disease (MASLD). However, this has not yet been investigated in Brazilian patients. In this study, we evaluated the association between the PNPLA3 variant rs738409 and MBOAT7 variant rs641738 and the risk of hepatic fibrosis or liver cirrhosis in MASLD etiology. In parallel, we also aimed to evaluate a protective SNP of the mitochondrial amidoxime-reducing component 1 (MTARC1) gene. We also evaluated TM6SF2 rs58542926, GCKR rs1260326 and rs780094, and HSD17B13 rs72613567 and they were not associated with liver fibrosis. The study was conducted at the Department of Gastroenterology and Nutrology, Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo (HCFMUSP), and included 113 patients with liver fibrosis (F0–F1), 99 patients with significant liver fibrosis (F2–F4), and 90 controls. SNPs were genotyped by quantitative PCR, using TaqMan allelic discrimination assays. Overall, the PNPLA3 GG genotype was more frequent in F2–F4 (23%) and F0–F1 (22%) patients than in controls (9%; p = 0.02). The MBOAT7 TT genotype was significantly associated with fibrosis, with a prevalence of 23% in F2–F4 patients versus 10% in F0–F1 and 11% in controls (p = 0.01). This association was confirmed by regression analysis (OR = 5.01 95% CI: 1.86–13.49; p = 1.41 × 10⁻³). The protective MTARC1 AA genotypes were more frequent in controls (52%) when compared to patients with fibrosis (5% p = 2.76 × 10⁻²⁰). Full article

Metabolic dysfunction-associated steatotic liver disease (MASLD) corresponds to the condition of increased hepatic fat levels, which is the leading cause of hepatic failure and carcinoma. It is also an independent risk factor for cardiovascular disease (CVD) and mortality. MASLD can be due to obesity with insulin resistance and/or genetic predisposition, i.e., polymorphism in the patatin-like phospholipase domain-containing 3 (PNPLA3) gene. PNPLA3 polymorphism has been associated with increased hepatic fat levels, fibrosis, cirrhosis, and hepatocellular carcinoma, while its association with CVD remains to be fully understood. The aim of the current study was to examine whether the vascular phenotype of patients with MASLD differed between carriers and noncarriers of the PNPLA3 polymorphism. Adult patients with MASLD underwent clinical assessment, PNPLA3 genotyping, arterial tonometry for aortic stiffness measurement, and ultrasound examination of carotid arteries. In total, 117 patients with MASLD and no fibrosis (median hepatic stiffness was 4.71 kPa) were recruited. Carriers of the PNPLA3 polymorphism were younger and exhibited higher levels of ALT and APRI, as compared to wild-type subjects. On the other hand, carriers of the PNPLA3 polymorphism had not only a better metabolic profile (i.e., lower glucose and glycated hemoglobin) but also lower blood pressure, carotid intima-media thickness (IMT), and cardiovascular risk. In addition, PNPLA3 polymorphism was negatively correlated with aortic stiffness, which is a marker of arteriolosclerosis and vascular ageing. Our data are consistent with previous observations that in case of genetically-driven MASLD, there is an inverse association with common predictors of CVD. Our data support the view that the main contributors to CVD risk in patients with MASLD remain conventional cardiometabolic risk factors (i.e., age, glucose) that are more likely to be found in metabolic syndrome-related MASLD rather than genetically-driven MASLD, at least in the first stages of the disease. Full article

Melanoma is one of the most lethal cancers originating from melanocytes. Its incidence and mortality have been rising rapidly for several decades and have posed a serious threat to human health. Current melanoma treatments are hindered by the scope of application, low efficiency, high cost, and toxic side effects. Due to their affordability and minimal side effects, natural bioactive compounds derived from plants are promising candidates for melanoma treatment. This study aims to delve into the isolation, purification, and characterization of potato proteins and to explore their potential in melanoma treatment. Two potato proteins, patatin PP-1 and aspartate protease inhibitor PP-2, were isolated and purified by a newly developed method in this work, and their physicochemical properties were systematically characterized. Both potato proteins showed great antiproliferative activities and migration inhibition effects on melanoma cells. Meanwhile, Western blotting results illustrated that they could induce endogenous cell apoptosis by regulating the Bax/Bcl-2 pathway. Notably, aspartate protease inhibitor PP-2 demonstrated the best performance in inhibiting the growth and migration of melanoma cells, which might be attributed to the combined effect of its significant antioxidative activity and the inhibition effect of certain necessary protease activities in melanoma. This study provides valuable insights for developing nutraceuticals and therapeutic strategies against melanoma, which can lead to breakthroughs in melanoma treatment. Full article

Background/Objectives: Low fasting blood lysosomal acid lipase (LAL) activity is associated with the pathogenesis of metabolic hepatic steatosis. We measured LAL activity in blood and plasma before and after an oral fat tolerance test (OFTT) in patients with metabolic-dysfunction-associated steatotic liver disease (MASLD). Methods: Twenty-six controls and seventeen patients with MASLD but without diabetes were genotyped for the patatin-like phospholipase 3 (PNPLA3) rs738409 variant by RT-PCR and subjected to an OFTT, measuring LAL activity in blood and plasma with a fluorimetric method. Results: LAL activity in blood both under fasting and 4 h after OFTT (0.846 ± 0.309 nmol/spot/h vs. 1.180 ± 0.503 nmol/spot/h p < 0.01) was lower in patients with MASLD compared to controls. These differences were present only in carriers of the PNPLA3 variant. In controls not carrying the PNPLA3 variant, the postprandial increase in blood LAL activity was negatively correlated with that of serum triglycerides (p < 0.05). Extracellular LAL activity in plasma was lower in patients with MASLD (n = 9) compared to controls (n = 8) in the fasting state (p < 0.01) and 4 h post-meal (p < 0.05). The area under the curve up to 6 h of plasma LAL activity was lower in patients with MASLD than in controls (p < 0.05) and correlated negatively with that of triglycerides only in controls (r = −0.841; p < 0.01). Conclusions: Patients with MASLD have reduced LAL activity in blood and plasma both before and 4 h after a meal. In patients with MASLD, the physiological negative correlation between circulating LAL levels and postprandial hypertriglyceridemia is lost. Full article

Background: Lacticaseibacillus paracasei (L. paracasei) strains and their postbiotics show potential for managing metabolic disorders such as diabetes and obesity. Two newly isolated L. paracasei strains, M2.1 and P4, were yielded from Formica rufa anthills in Sinite Kamani National Park, Bulgaria. Their metabolic effects on mature 3T3-L1 adipocytes were investigated. Methods: Mature 3T3-L1 adipocytes were treated for 24 h with 10% (v/v) cell-free supernatants (CFSs) of M2.1 or P4. Two experimental (M2.1, P4) and two control groups (mature, untreated adipocytes and mature adipocytes, treated with 10% (v/v) MRS broth) were analyzed for intracellular lipid accumulation, glucose uptake, and the mRNA expression of lipid metabolism and beta-oxidation-related genes. Fold changes in gene expression were assessed using RT-qPCR. Results: Both M2.1 and P4 CFSs enhanced glucose uptake by over 30% compared to the control. P4 demonstrated a more favorable effect by significantly upregulating adipose triglyceride lipase–patatin-like phospholipase domain containing 2, adiponectin, and peroxisomal beta-oxidation enzymes—acyl-coenzyme A oxidase 1, palmitoyl. Intracellular lipid accumulation increased only with M2.1, while P4 supported improved lipid turnover without promoting excessive lipid storage or lipolysis. Conclusions: P4 CFS exhibits the potential to improve adipocyte metabolism by enhancing glucose uptake, promoting beta-oxidation, and increasing adiponectin expression, offering a promising strategy for managing metabolic dysfunctions. Full article

The protein transition motivates the use of plant proteins, but their application in food emulsions is challenging, especially when high concentrations of oil and salt are needed for formulation and sensory properties. In the present work, we connect the iso-electric point of two potato protein isolates (patatin-rich, POPI-200; protease inhibitor-rich, POPI-300) and a faba protein isolate (FPI) to the behavior in the bulk phase and at the interface, and relate this to the physical stability of 45 wt% oil-in-water (O/W) emulsions in the presence of NaCl at pH 4.0–7.0. In the absence of NaCl, a higher bulk viscosity was found at the iso-electric point (IEP), especially for the FPI. In the presence of NaCl, the viscosity of the POPI-200 solutions was highest, followed by POPI-300, and that of the FPI was lowest, irrespective of the pH. Both POPIs showed faster initial adsorption at the O/W interface in the absence of NaCl, and formed a more elastic layer compared to the FPI. For all proteins, salt addition leads to less elastic films. Interestingly, the interfaces were more elastic at a pH close to the IEP of the protein in the presence of NaCl. Both POPI-stabilized emulsions showed higher stability (smaller size and less oiling off) than the FPI-stabilized emulsions, which makes potato proteins relevant for food emulsion product formulation, even under high salt conditions. Full article

Cow milk possesses high nutritional value due to its rich array of beneficial fatty acids. It is important to understand the mechanisms involved in lipid metabolism in dairy cows. These mechanisms are driven by a complex molecular regulatory network. In addition, there are many regulatory factors involved in the process of fatty acid metabolism, including transcription factors and non-coding RNAs, amongst others. MicroRNAs (miRNAs) can regulate the expression of target genes and modulate various biological processes, including lipid metabolism. Specifically, miR-206 has been reported to impair lipid accumulation in nonruminant hepatocytes. However, the effects and regulatory mechanisms of miR-206 on lipid metabolism in bovine mammary cells remain unclear. In the present study, we investigated the effects of miR-206 on lipid-related genes and TAG accumulation. The direct downstream gene of miR-206 was subsequently determined via a dual-luciferase assay. Finally, the fatty acid content of bovine mammary epithelial cells (BMECs) upon ELOVL6 inhibition was examined. The results revealed that miR-206 overexpression significantly decreased triacylglycerol (TAG) concentration and abundances of the following: acetyl-coenzyme A carboxylase alpha (ACACA); fatty acid synthase (FASN); sterol regulatory element binding transcription factor 1 (SREBF1); diacylglycerol acyltransferase 1 (DGAT1); 1-acylglycerol-3-phosphate O-acyltransferase 6 (AGPAT6); lipin 1 (LPIN1); and fatty acid elongase 6 (ELOVL6). Overexpression of miR-206 was also associated with an increase in patatin-like phospholipase domain-containing 2 (PNPLA2), while inhibition of miR-206 promoted milk fat metabolism in vitro. In addition, we found that ELOVL6 is a direct target gene of miR-206 through mutation of the binding site. Furthermore, ELOVL6 intervention significantly decreased the TAG levels and elongation indexes of C16:0 and C16:1n-7 in BMECs. Finally, ELOVL6 siRNA partially alleviated the increased TAG accumulation caused by miR-206 inhibition. In summary, we found that miR-206 inhibits milk fatty acid synthesis and lipid accumulation by targeting ELOVL6 in BMECs. The results presented in this paper may contribute to the development of strategies for enhancing the quality of cow milk and its beneficial fatty acids, from the perspective of miRNA–mRNA networks. Full article

This two-year study assessed nitrogen use efficiency (NUE) and its effect on potato tuber protein concentration, focusing on crude protein concentration (CPC), crude protein yield (CPY), and patatin relative abundance (PRA) across 19 potato genotypes and four nitrogen management treatments (organic with no added fertilizers and three integrated treatments with N rates of 60, 120, and 180 kg ha⁻¹). Nitrogen availability significantly affected CPC, with the highest average CPC across genotypes being 10.7% at 180 kg ha⁻¹ and the lowest of 8.15% at 60 kg ha⁻¹. Certain genotypes consistently outperformed others in terms of CPC and/or CPY under varying nitrogen treatments. A significant negative correlation was found between CPC and NUE, and genotypes with higher NUE typically had lower CPC. A positive correlation between CPY and NUE was observed, with the highest CPY of 1.36 t ha⁻¹ at 120 kg N ha⁻¹ in 2020. This suggests that higher NUE genotypes are more efficient in protein production per unit area. PRA varied significantly among genotypes, ranging from 8.7% to 35.51%. Although the relationship between NUE and PRA was weak, the significant and negative correlation indicates that cultivars with high NUE could have low PRA and vice versa. The findings underscore the importance of genotype variability in the relationship between NUE and protein content in potato tubers. Full article

The incidence of nonalcoholic fatty liver disease (NAFLD), or metabolic dysfunction-associated fatty liver disease (MAFLD), is increasing in adults and children. Unfortunately, effective pharmacological treatments remain unavailable. Single nucleotide polymorphisms (SNPs) in the patatin-like phospholipase domain-containing protein (PNPLA3 I148M) have the most significant genetic association with the disease at all stages of its progression. A roadblock to identifying potential treatments for PNPLA3-induced NAFLD is the lack of a human cell platform that recapitulates the PNPLA3 I148M-mediated onset of lipid accumulation. Hepatocyte-like cells were generated from PNPLA3^−/− and PNPLA3^I148M/M-induced pluripotent stem cells (iPSCs). Lipid levels were measured by staining with BODIPY 493/503 and were found to increase in PNPLA3 variant iPSC-derived hepatocytes. A small-molecule screen identified multiple compounds that target Src/PI3K/Akt signaling and could eradicate lipid accumulation in these cells. We found that drugs currently in clinical trials for cancer treatment that target the same pathways also reduced lipid accumulation in PNPLA3 variant cells. Full article

Leptin regulates lipid metabolism, maximizing insulin sensitivity; however, peripheral leptin resistance is not fully understood, and its contribution to metabolic dysfunction-associated steatotic liver disease (MASLD) is unclear. This study evaluated the contribution of the leptin axis to MASLD in humans. Forty-three participants, mostly female (86.04%), who underwent cholecystectomy were biopsied. Of the participants, 24 were healthy controls, 8 had MASLD, and 11 had metabolic dysfunction-associated steatohepatitis (MASH). Clinical and biochemical data and the gene expression of leptin, leptin receptor (LEPR), suppressor of cytokine signaling 3 (SOCS3), sterol regulatory element-binding transcription factor 1 (SREBF1), stearoyl-CoA desaturase-1 (SCD1), and patatin-like phospholipase domain-containing protein 2 (PNPLA2), were determined from liver and adipose tissue. Higher serum leptin and LEPR levels in the omental adipose tissue (OAT) and liver with MASH were found. In the liver, LEPR was positively correlated with leptin expression in adipose tissue, and SOCS3 was correlated with SREBF1-SCD1. In OAT, SOCS3 was correlated with insulin resistance and transaminase enzymes (p < 0.05 for all. In conclusion, we evidenced the correlation between the peripheral leptin resistance axis in OAT–liver crosstalk and the complications of MASLD in humans. Full article