Research progress into the physiological changes in metabolic pathways in waterfowl with hepatic steatosis

Abstract Background: Dietary sphingomyelin was showed to inhibit the uptake of lipids in mice fed with a high-fat diet, however, the effect of sphingomyelin on normal diet was on reported. The current study aims to examine the effects of sphingomyelin extracts from yak butter on hepatic steatosis and inflammation in C57/B6J mice fed with a normal diet. Methods: A UHPLC-QTOF-MS based lipidomics method was utilized to screen the liver metabolites and predict the dominant potential metabolic pathways after sphingomyelin feeding. Results: The results showed that sphingomyelin extracts reduced the accumulation of lipid droplets, suppressed the expression of pro-inflammatory factors IFN -γ, IL-6 and TNF - α, synchronously, promoted the expression of anti-inflammatory factors IL-10, IL-4 and IL-1Ra. In addition, sphingomyelin extracts exhibited the modulation on liver lipid metabolism when supplement sphingomyelin in normal diet for one month and five months. Specifically, 16, 68 different metabolites and 2, 6 metabolic pathways were identified by quantitative lipidomics, respectively. Six CERs including Cer(d18:1/18:0), Cer(d18:1/20:0), Cer(d17:1/22:0), Cer(d17:1/24:1), Cer(d17:1/24:0) and Cer(d17:0/26:1), six SMs including SM(d15:0/24:1), SM(d14:0/26:1), SM(d14:1/24:1), SM(d15:1/22:0), SM(d15:1/24:1) and SM(d19:1/26:1), and PS(18:1/22:6) were identified and can be used as potential biomarkers of steatosis and inflammation.Conclusions: This study highlighted the effects of yak butter sphingomyelin on hepatic steatosis, tissue inflammation and lipid metabolism of mice under a normal diet.

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Review of Machine Learning Methods for the Prediction and Reconstruction of Metabolic Pathways

Frontiers in Molecular Biosciences ◽

10.3389/fmolb.2021.634141 ◽

2021 ◽

Vol 8 ◽

Author(s):

Hayat Ali Shah ◽

Juan Liu ◽

Zhihui Yang ◽

Jing Feng

Keyword(s):

Machine Learning ◽

Synthetic Biology ◽

Metabolic Pathways ◽

Machine Learning Techniques ◽

Research Progress ◽

Related Data ◽

Pathway Reconstruction ◽

Learning Techniques ◽

Machine Leaning ◽

Active Research

Prediction and reconstruction of metabolic pathways play significant roles in many fields such as genetic engineering, metabolic engineering, drug discovery, and are becoming the most active research topics in synthetic biology. With the increase of related data and with the development of machine learning techniques, there have many machine leaning based methods been proposed for prediction or reconstruction of metabolic pathways. Machine learning techniques are showing state-of-the-art performance to handle the rapidly increasing volume of data in synthetic biology. To support researchers in this field, we briefly review the research progress of metabolic pathway reconstruction and prediction based on machine learning. Some challenging issues in the reconstruction of metabolic pathways are also discussed in this paper.

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Contributions of microRNAs to peripheral insulin sensitivity

Endocrinology ◽

10.1210/endocr/bqab250 ◽

2021 ◽

Author(s):

Kang Ho Kim ◽

Sean M Hartig

Keyword(s):

Insulin Sensitivity ◽

Metabolic Pathways ◽

Metabolic Diseases ◽

Research Progress ◽

Extensive Literature ◽

Peripheral Tissues ◽

Sequencing Technologies ◽

Glucose And Lipid Metabolism ◽

Target Spectrum ◽

Literature Base

Abstract An extensive literature base combined with advances in sequencing technologies demonstrated microRNA levels correlate with various metabolic diseases. Mechanistic studies also establish microRNAs regulate central metabolic pathways and thus play vital roles in maintaining organismal energy balance and metabolic homeostasis. This review highlights research progress on the roles and regulation of microRNAs in the peripheral tissues that confer insulin sensitivity. We discuss sequencing technologies used to comprehensively define the target spectrum of microRNAs in metabolic disease that complement studies reporting physiologic roles for microRNAs in the regulation of glucose and lipid metabolism in animal models. We also discuss the emerging roles of exosomal microRNAs as endocrine signals to regulate lipid and carbohydrate metabolism.

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Review: Endoplasmic Reticulum-Associated Degradation (ERAD)-Dependent Control of (Tri)terpenoid Metabolism in Plants

Planta Medica ◽

10.1055/a-0635-8369 ◽

2018 ◽

Vol 84 (12/13) ◽

pp. 874-880 ◽

Cited By ~ 2

Author(s):

Marie-Laure Erffelinck ◽

Alain Goossens

Keyword(s):

Endoplasmic Reticulum ◽

Metabolic Pathways ◽

Regulatory Networks ◽

Enzyme Stability ◽

Environmental Stresses ◽

Research Progress ◽

Transcriptional Level ◽

Posttranslational Regulation ◽

Terpenoid Biosynthesis ◽

Endoplasmic Reticulum Associated Degradation

AbstractPlants are sessile organisms. Therefore, they developed the capacity to quickly respond to biotic and abiotic environmental stresses, for instance by producing a broad spectrum of bioactive specialized metabolites. In this defense response, the jasmonate phytohormones can instigate a signaling cascade that leads to the specific elicitation and reprograming of numerous metabolic pathways. Recent research progress has provided several insights into the regulatory networks of many specialized metabolic pathways, mainly at the transcriptional level. Nonetheless, our view on the regulation of defense metabolism remains far from comprehensive. Here, we describe the recent advances obtained with regard to one aspect of the regulation of plant specialized metabolism, namely the posttranslational regulation of enzyme stability. We focus on terpenoid biosynthesis and in particular on the rate-limiting and well-investigated enzyme of the terpenoid precursor pathway, 3-hydroxy-3-methylglutaryl-coenzyme A reductase (HMGR). There are clear similarities, as well as important mechanistic differences, among the components involved in the posttranslational regulation of terpenoid biosynthesis via HMGR in plants, yeasts, and mammals. Furthermore, in plants, several of these components evolved to respond to specific signaling cues. Indeed, the elements of the plant endoplasmic reticulum-associated degradation (ERAD) and ER stress-associated processes can be induced upon environmental stresses and during specific developmental processes, thereby allowing a unique posttranslational regulation of terpenoid biosynthesis pathways.

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Circular RNA Profiling and Bioinformatic Modeling Identify Its Regulatory Role in Hepatic Steatosis

BioMed Research International ◽

10.1155/2017/5936171 ◽

2017 ◽

Vol 2017 ◽

pp. 1-13 ◽

Cited By ~ 17

Author(s):

Xing-Ya Guo ◽

Chong-Xin He ◽

Yu-Qin Wang ◽

Chao Sun ◽

Guang-Ming Li ◽

...

Keyword(s):

Hepatic Steatosis ◽

Metabolic Pathways ◽

Target Prediction ◽

Principal Component ◽

Circular Rna ◽

Circular Rnas ◽

Rna Profiling ◽

Pathway Annotation ◽

Wide Range ◽

Chain Acyl

Circular RNAs (circRNAs) exhibit a wide range of physiological and pathological activities. To uncover their role in hepatic steatosis, we investigated the expression profile of circRNAs in HepG2-based hepatic steatosis induced by high-fat stimulation. Differentially expressed circRNAs were subjected to validation using QPCR and functional analyses using principal component analysis, hierarchical clustering, target prediction, gene ontology (GO), and pathway annotation, respectively. Bioinformatic integration established the circRNA-miRNA-mRNA regulatory network so as to identify the mechanisms underlying circRNAs’ metabolic effect. Here we reported that hepatic steatosis was associated with a total of 357 circRNAs. Enrichment of transcription-related GOs, especially GO: 0006355, GO: 004589, GO: 0045944, GO: 0045892, and GO: 0000122, demonstrated their specific actions in transcriptional regulation. Lipin 1 (LPIN1) was recognized to mediate the transcriptional regulatory effect of circRNAs on metabolic pathways. circRNA-miRNA-mRNA network further identified the signaling cascade of circRNA_021412/miR-1972/LPIN1, which was characterized by decreased level of circRNA_021412 and miR-1972-based inhibition of LPIN1. LPIN1-induced downregulation of long chain acyl-CoA synthetases (ACSLs) expression finally resulted in the hepatosteatosis. These findings identify circRNAs to be important regulators of hepatic steatosis. Transcription-dependent modulation of metabolic pathways may underlie their effects, partially by the circRNA_021412/miR-1972/LPIN1 signaling.

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Microalgal–bacterial consortia unveil distinct physiological changes to facilitate growth of microalgae

FEMS Microbiology Ecology ◽

10.1093/femsec/fiab012 ◽

2021 ◽

Author(s):

Isiri Adhiwarie Perera ◽

Sudharsanam Abinandan ◽

Suresh R Subashchandrabose ◽

Kadiyala Venkateswarlu ◽

Ravi Naidu ◽

...

Keyword(s):

Chlorophyll A ◽

Metabolic Pathways ◽

Basal Medium ◽

Value Added ◽

Differential Regulation ◽

Oxygen Species ◽

Physiological Changes ◽

Bacterial Consortia ◽

Variovorax Paradoxus ◽

Tetradesmus Obliquus

Abstract Physiological changes that drive the microalgal–bacterial consortia are poorly understood so far. In the present novel study, we initially assessed five morphologically distinct microalgae for their ability in establishing consortia in Bold's basal medium with a bacterial strain, Variovorax paradoxus IS1, all isolated from wastewaters. Tetradesmus obliquus IS2 and Coelastrella sp. IS3 were further selected for gaining insights into physiological changes including those of metabolomes in consortia involving V. paradoxus IS1. The distinct parameters investigated were pigments (chlorophyll a, b, and carotenoids), reactive oxygen species (ROS), lipids, and metabolites that are implicated in major metabolic pathways. There was a significant increase (>1.2-fold) in pigments, viz., chlorophyll a, b and carotenoids, decrease in ROS, and enhanced lipid yield (>2-fold) in consortia than in individual cultures. In addition, the differential regulation of cellular metabolites such as sugars, amino acids, organic acids, and phytohormones was distinct among the two microalgal–bacterial consortia. Our results thus indicate that the selected microalgal strains, T. obliquus IS2 and Coelastrella sp. IS3, developed efficient consortia with V. paradoxus IS1 by effecting the required physiological changes including metabolomics. Such microalgal–bacterial consortia could largely be used in wastewater treatment and for production of value-added metabolites.

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L-theanine Prevents Progression of Nonalcoholichepatic Steatosis by Regulating Hepatocyte Lipid Metabolic Pathways via the CaMKKβ-AMPK Signaling Pathway

10.21203/rs.3.rs-820686/v1 ◽

2021 ◽

Author(s):

Juanjuan Liang ◽

Lili Gu ◽

Xianli Liu ◽

Xintong Yan ◽

Xiaowen Bi ◽

...

Keyword(s):

Fatty Acid ◽

Protein Kinase ◽

Signaling Pathway ◽

Hepatic Steatosis ◽

Metabolic Pathways ◽

Alcoholic Fatty Liver ◽

Ampk Signaling ◽

Nonalcoholic Hepatic Steatosis

Abstract Background: L-theanine, a non-protein amino acid found principally in the green tea, has been previously shown to possess potent anti-obesity property and hepatoprotective effect. Herein, we investigated the effects of L-theanine on alleviating nonalcoholic hepatic steatosis in vitro and in vivo, and explored the underlying molecular mechanism. Methods: In vitro, HepG2 and AML12 cells were treated with 500 μM oleic acid (OA) or treated with OA accompanied by L-theanine. In vivo, C57BL/6J mice were fed with normal control diet (NCD), high‐fat diet (HFD), or HFD along with L-theanine for 16 weeks. The levels of TG, accumulation of lipid droplets and the expression of genes related to hepatocyte lipid metabolic pathways were detected in vitro and in vivo.Results: Our data indicated that, in vivo, L-theanine significantly reduced body weight, hepatic steatosis, serum levels of alanine transaminase (ALT), aspartate transaminase (AST), TG and LDL cholesterol (LDL-C) in HFD-induced Non-alcoholic fatty liver disease (NAFLD) mice. In vitro, L-theanine also significantly alleviated OA induced hepatocytes steatosis. Mechanic studies showed that L-theanine significantly inhibited the nucleus translocation of sterol regulatory element binding protein 1c (SREBP-1c) through AMPK-mTOR signaling pathway, thereby contributing to the reduction of fatty acid synthesis. We also identified that L-theanine enhanced fatty acid β-oxidation by increasing the expression of peroxisome proliferator–activated receptor α (PPARα) and carnitine palmitoyltransferase-1 A (CPT1A) through AMP-activated protein kinase (AMPK). Furthermore, our study indicated that L-theanine can active AMPK via its upstream kinase Calmodulin-dependent protein kinase kinase-β (CaMKKβ). Conclusions: Taken together, our findings suggest that L-theanine alleviates nonalcoholic hepatic steatosis by regulating hepatocyte lipid metabolic pathways via the CaMKKβ-AMPK signaling pathway.

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Research Progress in the Interconversion, Turnover and Degradation of Chlorophyll

Cells ◽

10.3390/cells10113134 ◽

2021 ◽

Vol 10 (11) ◽

pp. 3134

Author(s):

Xueyun Hu ◽

Tongyu Gu ◽

Imran Khan ◽

Ahmad Zada ◽

Ting Jia

Keyword(s):

Metabolic Pathways ◽

Recent Progress ◽

Environmental Changes ◽

Energy Transduction ◽

Research Progress ◽

Degradation Pathways ◽

Chl A ◽

Photosynthetic Proteins ◽

Open Questions ◽

Fruitful Research

Chlorophylls (Chls, Chl a and Chl b) are tetrapyrrole molecules essential for photosynthetic light harvesting and energy transduction in plants. Once formed, Chls are noncovalently bound to photosynthetic proteins on the thylakoid membrane. In contrast, they are dismantled from photosystems in response to environmental changes or developmental processes; thus, they undergo interconversion, turnover, and degradation. In the last twenty years, fruitful research progress has been achieved on these Chl metabolic processes. The discovery of new metabolic pathways has been accompanied by the identification of enzymes associated with biochemical steps. This article reviews recent progress in the analysis of the Chl cycle, turnover and degradation pathways and the involved enzymes. In addition, open questions regarding these pathways that require further investigation are also suggested.

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