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The synthesis of n-3 and n-6 polyunsaturated acids (PUFAs) is associated with physiological functions in mammals, being catalyzed by Δ-5D and Δ-6D desaturases and elongases Elovl-2 and Elovl-5. In this context, we aimed to study the chief kinetic features of PUFA liver anabolism, looking upon (i) the time-dependency for the specific activity of Δ-6D, Δ-5D, Elovl2, Elovl2/5 and Elovl5, using n-3 and n-6 precursors between 0 and 240 min ex vivo in mouse liver.; and (ii) the specific activity-substrate (α-linolenic acid; ALA) concentration responses of Δ-6D in the absence and presence of linoleic acid (LA), arachidonic acid (ARA), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), an enzyme regarded as the rate-limiting step in PUFA anabolism. Mouse liver was obtained from eight-week-old Balb/c mice fed a chow diet (expressed as % of total calories: 18 % fat, 24 % protein, and 58 % carbohydrate, with a caloric value of 3.1 kcal/g) for eight weeks, and used for preparation of the microsomal fraction. Enzymatic activities assayed under the addition of specific PUFA precursors or LA, ARA, EPA and DHA, identifying the respective PUFA products as fatty acid methyl esters by gas chromatographic analysis. Data described corroborate that (i) PUFA metabolism mainly occurs in the liver, with the participating enzymes preferring n-3 than n-6 substrates; and show that (ii) the rate-limiting step of PUFA metabolism relies on the second reaction of Δ-6D (24:5n-3 transformed to 24:6n-3); and (iii) LA, ARA, EPA and DHA act as non-competitive inhibitors with respect to ALA in the reaction catalyzed by Δ-6D. These results are relevant for future studies concerning the metabolic and nutritional implications of changes in desaturation and elongation of PUFAs., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2025. Published by Elsevier B.V.)

Consumption of phytosterols is a nutritional strategy employed to reduce cholesterol absorption, but recent research shows that their biological activity might go beyond cholesterol reduction for the treatment of metabolic dysfunction-associated fatty liver disease (MAFLD), and novel phytosterol formulations, such as submicron dispersions, could improve these effects. We explored the therapeutic activity of phytosterols, either formulated as submicron dispersions of phytosterols (SDPs) or conventional phytosterol esters (PEs), in a mouse model of MAFLD. MAFLD was induced in mice by atherogenic diet (AD) feeding. The reversion of distorted serum and liver parameter values after a period of AD feeding was investigated after supplementation of the AD with SDPs, PEs, or a placebo (PT). Additionally, the metabolic parameters of fatty acid synthesis, fatty acid oxidation, and inflammation were studied to understand the mechanism of action of phytosterols. AD supplementation with SDPs was shown to reduce liver fat, along with showing a significant improvement in liver triglycerides (TGs), free fatty acids (FFAs), and liver cholesterol levels. These results were reinforced by the analyses of the liver steatosis scores, and liver histologies, where SDP intervention showed a consistent improvement. Treatment with PEs showed slighter effects in the same analyses, and no effects were observed with the PT treatment. Additionally, SDP intervention reversed, with a higher efficacy than PEs, the effect of AD on the serum levels of TGs, total- and LDL-cholesterol levels, and glucose levels. And, exceptionally, while SDP improved HDL-cholesterol serum levels, PEs did not show any effect on this parameter. We provide evidence for the therapeutical activity of phytosterols in MAFLD beyond the regulation of cholesterol levels, which is increased when the phytosterols are formulated as submicron dispersions compared to ester formulations.

Patellaria species are widely distributed in terrestrial and marine habitats and are saprobes growing on decaying wood, stems, or bark. However, studies on this genus in Mexico are limited, and only the type species Patellaria atrata Fr. has been cited. This study describes twelve new Patellaria species in Mexico supported by molecular (ITS-LSU-SSU) and morphological data. Phylogenetic analysis shows that species of this genus in Mexico are not closely related to Patellaria atrata. Moreover, the results demonstrate that the greatest species diversity is found in dry climates, particularly in xerophilous scrub.

Introduction: This study aimed to determine the burden of suspected nonalcoholic fatty liver disease (NAFLD) and nonalcoholic steatohepatitis (NASH) in a predominantly Hispanic patient population and explore the utility of the American Gastroenterological Association's NAFLD Clinical Care Pathway (CCP)., Methodology: Electronic medical records ( n = 223) were used to divide patients into risk groups based on the amount of metabolic risk factors they presented, diabetic status, or if they presented other liver diseases. Fribosis-4 (FIB-4) scores were used to determine the risk for advanced fibrosis., Results: Most patients (83.8%) were considered at risk for NAFLD based on CCP criteria, and about a third of patients (33.2%) were found to be at indeterminate ( n = 60; 26.9%) or high risk ( n = 14; 6.3%) for advanced fibrosis. Most indeterminate-risk patients (78.3%) were not referred for liver imaging., Discussion: This study demonstrates the potential of the CCP as a corrective tool that could help to better identify and screen patients at risk for NAFLD., Competing Interests: Declaration of Conflicting InterestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.