Regulation Of Lipid Metabolism Research Articles

Quantitative Proteomics Reveal the Role of Matrine in Regulating Lipid Metabolism.

Hyperlipidemia (HLP) is a prevalent systemic metabolic disorder characterized by disrupted lipid metabolism. Statin drugs have long been the primary choice for managing lipid levels, but intolerance issues have prompted the search for alternative treatments. Matrine, a compound derived from the traditional Chinese medicine Kushen, exhibits anti-inflammatory and lipid-lowering properties. Nevertheless, the mechanism by which matrine modulates lipid metabolism remains poorly understood. Here, we investigated the molecular mechanisms underlying matrine's regulation of lipid metabolism. Employing quantitative proteomics, we discovered that matrine increases the expression of LDL receptor (LDLR) in HepG2 and A549 cells, with subsequent experiments validating its role in enhancing LDL uptake. Notably, in hyperlipidemic hamsters, matrine effectively lowered lipid levels without affecting body weight, which highlights LDLR as a critical target for matrine's impact on HLP. Moreover, matrine's potential inhibitory effects on tumor cell LDL uptake hint at broader applications in cancer research. Additionally, thermal proteome profiling analysis identified lipid metabolism-related proteins that may interact with matrine. Together, our study reveals matrine's capacity to upregulate LDLR expression and highlights its potential in treating HLP. These findings offer insights into matrine's mechanism of action and open new avenues for drug research and lipid metabolism regulation.

Unraveling the metabolic pattern of angiopoietin-like 3 knock-out mouse models under fasting and fed conditions

Abstract Funding Acknowledgements Type of funding sources: Public Institution(s). Main funding source(s): University of Milan Background Angiopoietin-like 3 (ANGPTL3) is a hepatokine and a regulator of lipid and lipoprotein metabolism through lipoprotein lipase and endothelial lipase inhibition, preventing the hydrolyzation of lipoprotein-derived triglycerides. A lack of ANGPTL3 results into a hypolipidemic phenotype, with a lower profile of lipids and lipoproteins, and this is evident in humans carrying a loss of function mutation, or in cellular or in vivo models. ANGPTL3 action, from the liver, is finely regulated between oxidative and storage tissues in the fasting and postprandial phases; from the current pharmacological treatments a possible ANGPTL3 intrahepatic role besides the lipases’ inhibition is emerging, thus possibly affecting the systemic metabolism with different implications. Purpose An axis between ANGPTL3 and other Angiopoietin-like proteins is known to regulate the triglyceride partitioning after a meal or during fasting, however the effect on tissues and the following metabolic and pathologic implications are still not known. Therefore, we aim to describe the impact of ANGPTL3 deficiency in fasting or in a postprandial state, and in different compartments of the organism. Methods As models, we utilized Angptl3 Knock-out (KO) mice (C57BL6/J background) and their littermate controls (wild-type, WT) fed a chow diet for 16 weeks. We assessed the metabolic phenotype with indirect calorimetry and with lipids, glucose, and insulin tolerance tests; we evaluated changes in plasma lipids under fast, fed, and fast-refeed settings and we investigated the histology of key metabolic organs. Results ANGPTL3 KO mice fed ad libitum a chow diet are hypolipidemic (plasma triglycerides levels: 42,42±8,80 mg/dL in ANGPTL3 KO mice vs. 122,02±55,09 mg/dL in WT mice; plasma cholesterol levels: 44,00±9,11 mg/dL in ANGPTL3 KO mice vs. 76,51±15,87 mg/dL in WT mice). The oral charge lipid challenge suggests that KO mice have lower lipid levels at all time points. Conclusions This preliminary profiling of ANGPTL3 KO mice under fasting and fed conditions highlights the hypolipidemia of these models, and the potentially beneficial impact of ANGPTL3 deficiency on their metabolism compared to controls.

Prediction of the Signaling Pathway in Polycystic Ovary Syndrome Using an Integrated Bioinformatics Approach.

Objectives The purpose of this study was to define the underlying biological mechanisms of PCOS utilizing the protein-protein interaction networks that were constructed based on the putative disease-causing genes for PCOS. Design No animals were used in this research because this study is an In-Silico studies which mainly uses softwares and online analysis tools. Participants/Materials, Settings Genes datasets related with PCOS were obtained from Genecard. Methods The protein-protein interaction networks (PPIN) of PCOS were created using the String Database after genes related with PCOS were obtained from Genecard. After that, we performed an analysis of the hub-gene clusters extracted from the PPIN using the ShinyGO algorithm. In the final step of this research project, functional enrichment analysis was used to investigate the primary biological activities and signaling pathways that were associated with the hub clusters. Results The Genecard database provided the source for the identification of a total of 1072 potential genes related with PCOS. The PPIN that was generated by using the genes that we collected above contained a total of 82 genes and three different types of cluster interaction interactions. In addition, after conducting research on the PPIN with the shinyGO plug-in, 19 of the most important gene clusters were discovered. The primary biological functions that were enriched in the key clusters that were developed were ovarian stereoidogenesis, breast cancer pathway, regulation of lipid and glucose metabolism by AMPK pathway, and ovarian stereoidogenesis. The integrated analysis that was performed in the current study demonstrated that these hub clusters and their connected genes are closely associated to the pathogenesis of PCOS. Limitations Several of the significant genes that were identified in this study, such as ACVR1, SMAD5, BMP6, SMAD3, SMAD4 and AMH. It is necessary to do additional research using large samples, several centers, and multiple ethnicities in order to verify these findings. Conclusions The integrated analysis that was performed in the current study demonstrated that these hub clusters and their connected genes are closely associated to the pathogenesis of PCOS. This information may possibly bring unique insights for the treatment of PCOS as well as the investigation of its underlying pathogenic mechanism.

Fermented red rice improved the antioxidant activity, bioaccessibility of polyphenols, and lipid‐lowering activity in C. elegans

AbstractRed rice is a kind of whole grain with health benefits. Probiotic fermentation is widely applied to promote nutrient release from cereals and improve bioactivity. The study aims to investigate the impact of Lactiplantibacillus plantarum (L. plantarum) dy‐1 fermentation on the bioactivities, bioaccessibility, and lipid‐lowering activities of red rice. Results indicated that fermentation significantly increased the protein and total phenolic content by 1.7 and 1.4 times of red rice, as well as the content of essential and nonessential amino acids. Fermentation remarkably increased the bioaccessibility of phenolics and the antioxidant capacity of red rice during in vitro digestion. Additionally, Caenorhabditis elegans study revealed that fermented red rice extract reduced the triglyceride content, alleviated fat deposition, and regulated lipid metabolism by altering the genes in the fatty acid oxidation and synthesis, such as daf‐16, mdt‐15, nhr‐49, fat‐5, fat‐7, and hosl‐1. Therefore, L. plantarum dy‐1 fermentation was beneficial for improving bioaccessibility and lipid‐lowering activities of red rice, which will provide a reference for utilization of red rice as a functional food.

PCSK9 aggravated carotid artery stenosis in ApoE-/- mice by promoting the expression of tissue factors in endothelial cells via the TLR4/NF-κB pathway

Atherosclerosis, a chronic inflammatory disease, is the most relevant cause of carotid artery stenosis. Vascular endothelial cells (ECs) play a significant role in the development of atherosclerosis. In this chronic inflammatory environment, we aimed to investigate whether PCSK9 could mitigate atherosclerosis progression by reducing tissue factor expression in ECs via in vivo and in vitro assays. In vivo, we investigated the effect of PCSK9 inhibition on preventing atherosclerotic lesion formation in ApoE-/- mice fed a western diet. The results showed that inhibiting PCSK9 could significantly downregulate the protein expression of tissue factor (TF) in ECs to reduce the area of atherosclerotic plaques. In vitro, we incubated human umbilical vein endothelial cells (HUVECs) with lipopolysaccharide (LPS). We found that LPS-induced TF elevation was suppressed by a PCSK9 inhibitor at both the mRNA and protein levels and that the TLR4/NF-κB pathway was also suppressed by a PCSK9 inhibitor. With respect to plasma samples from patients with carotid artery stenosis, we also demonstrated that the expression of TF was positively correlated with that of PCSK9. Thus, in addition to regulating lipid metabolism, the regulation of endothelial cell TF expression through the TLR4/NF-κB pathway may be a potential mechanism of PCSK9 in promoting atherosclerotic carotid stenosis.

Resveratrol and (-)-Epigallocatechin-3-gallate Regulate Lipid Metabolism by Activating the AMPK Pathway in Hepatocytes.

The purpose of this study was to explore the effects of Res and EGCG on cell growth, cellular antioxidant levels, and cellular lipid metabolism in hepatocytes. In this experiment, leghorn male hepatoma (LMH) cells were used as hepatocytes. The results showed that 6.25-25 μM Res and EGCG had no adverse effects on cell viability and growth. Meanwhile, with the increasing dosage of Res and EGCG, the contents of total cholesterol (TC), total glyceride (TG), and malondialdehyde (MDA) in hepatocytes decreased significantly (p < 0.05), while the contents of glutathione peroxidase (GSH-Px), total superoxide dismutase (T-SOD), and catalase (CAT) increased significantly (p < 0.05). In addition, western blot results showed that Res and EGCG could significantly increase the expression of p-AMPK protein and reduce the expression of 3-hydroxy-3-methylglutaryl-CoA reductase (HMGCR) protein in hepatocytes (p < 0.05). Moreover, q-PCR results showed that with the increase in Res and EGCG, the expression of cholesterol- and fatty acid synthesis-related genes decreased significantly (p < 0.05). In conclusion, Res and EGCG can increase the antioxidant capacity of hepatocytes and reduce the synthesis of TC and TG in hepatocytes by activating AMPK, thereby regulating lipid metabolism in hepatocytes.

#1326 Impairment of ACSS2 aggravates renal fibrosis and cell senescence during aging

Abstract Background and Aims Age-related changes in kidney function, structure, and their relationships have been extensively recognized recently. Here, we report that acyl-CoA synthetase short chain family member 2 (Acss2) as a regulator of lipid metabolism, play an important role in age-associated renal fibrosis. Method 21-month-old Acss2 knockout (Acss2−/−) mice were used as the renal aging models, and H2O2 also was used to induced renal tubular epithelial cells (TCMK-1) senescence. Serum creatinine (Cr) and urinary protein creatinine ratio (UACR) were measured to evaluate kidney function, and renal tissue lesions were observed by HE staining and Masson staining. The expression of gene/protein in relation to inflammation, fibrosis and cell senescence were measured by qPCR, western blot. SA-β-gal staining also used to assess cell senescence. Results The results indicate that Acss2 was decreased in aging mice, Acss2 knockout impaired renal function as detected by increased UACR. Additionally, HE and Masson staining showed that Acss2 deficiency was associated with more glomerular sclerosis and fibrosis (Fig. 1). RT-qPCR and Western blotting also revealed that Acss2 enhanced kidney fibrosis and cell senescence, accompanied by an increase in SA-β-gal-positive senescent cells (Fig. 2). These phenomena were most apparent in the TCMK cells treated with Acss2 siRNA and H2O2 (Fig. 3). What's more, KEGG analysis showed that fatty acid metabolism changes significantly during aging in kidney, and Acss2 knockout could impact the expression of lipid metabolism genes (Fig. 4) Conclusion Acss2 is associated with renal aging, and it may played a role in renal fibrosis and cell senescence by regulating fatty acid metabolism.

#1144 Role of PPAR-alpha in folic acid-induced tubulointerstitial fibrosis

Abstract Background and Aims PPAR-alpha is a nuclear receptor that plays a major role in the regulation of lipid metabolism. Activation of PPAR-alpha has been shown to have beneficial effects in renal diseases. Acute kidney injury (AKI), even if followed by renal recovery, is a risk factor for the future development of chronic kidney disease (CKD) and end-stage renal disease (ESRD). Progressive tubulointerstitial fibrosis is the final common pathway for all kidney diseases leading to chronic renal failure. Our main objective was to determine the importance of PPAR-alpha in tubulointerstitial fibrosis in folic acid induced nephropathy. Method Male C57/Bl6 and PPARKO (C57Bl6 background) mice were divided into 4 groups, Control, Folic Acid, Gemfibrozil + Folic Acid and PPARKO + Folic Acid. Animals have been treated with a single dose of Folic Acid (250 mg/kg i.p) and Gemfibrozil (150 mg/kg gavage) euthanized after 28 days for. Renal parameters, histology, real time PCR were performed to investigate renal injury, inflammation, and fibrosis. Results After 28 days of folic acid inducing CKD. PPARKO showed the same levels of injury as folic acid alone treated mice, however PPAR-alpha activation with gemfibrozil decreased urinary volume (Folic Acid: 3.870 ± 0.679 Gemfibrozil: 1,242 ± 0,223), creatinine (Folic Acid: 0,7940 ± 0,0357 Gemfibrozil: 0,5820 ± 0,0288), urea levels (Folic Acid: 79,23 ± 3,20 Gemfibrozil: 46,11 ± 3,874), showed less tubulointerstitial fibrosis (Folic Acid: 0,5837 ± 0,0426), Gemfibrozil: 0,2423 ± 0,0293) and lower urine protein/creatinine ratio (Folic Acid: 5,486 ± 0,588 Gemfibrozil: 2,536 ± 0,127). Conclusion PPAR-alpha deletion did not show protection in chronic phase, in the other hand PPAR-alpha activation with gemfibrozil showed to be effective against tubulointerstitial fibrosis.

Characterization and evaluation of MFG-E8 protein-derived peptides: From isolation to functional assessment in skeletal muscle lipid metabolism

This research investigated preparation, identification and relative properties of milk fat globule epidermal growth factor Ⅷ (MFG-E8) protein-derived peptides. MFG-E8 protein was extracted from bovine milk and peptides were isolated and obtained using an in vitro simulating gastrointestinal digestion model, the peptide sequence was then identified. High-abundance MFG-E8 peptides bind well to the protein domain of pancreatic lipase was selected. Enzyme kinetic studies exhibited that the inhibition effect of KDPG and YAR on pancreatic lipase activity was reversible and non-competitive inhibition. Fluorescence spectroscopic analysis showed that KDPG and YAR acted as fluorescence quenchers of pancreatic lipase and exhibited certain dose-dependent effect. In vivo animal experiments further verified the regulatory effects of MFG-E8 peptides on lipid metabolism and skeletal muscle profiles, which provided the potential role of KDPG and YAR in regulating lipid metabolism and alleviating skeletal muscle dysfunction via AMPK/SREBP-1/SCD-1 signaling pathway.

Wild thyme (Thymus serpyllum L.): a review of the current evidence of nutritional and preventive health benefits*

Thymus serpyllum L. (Lamiaceae), known in English as ‘wild thyme’, is primarily found in the Palearctic realm (Eurasia, North Africa) and has been utilized traditionally for culinary, nutritional, medicinal, and aromatic purposes. The essential oil extracted from wild thyme is particularly noteworthy, being used extensively in the food industry as a flavoring agent and preservative. The plant’s aerial parts are commonly employed as an element of the diet (e.g., tea)/for culinary uses and in local/traditional medicine (primarily for managing respiratory and gastrointestinal conditions), similar to the use of common thyme. There is practically no information available on the species’ nutritional benefits. Pharmacological studies, including in vitro and in vivo research, alongside a limited number of clinical trials, have investigated extracts of Thymus serpyllum, although these extracts are often phytochemically poorly characterized in different experimental protocols and models. These studies have demonstrated a range of therapeutic effects, such as antimicrobial (notably the essential oil) and anti-inflammatory, as well as its preventative health benefits and nutritional value of wild thyme. Preclinical studies have corroborated the plant’s anti-inflammatory potential, particularly in conditions like inflammatory bowel diseases (IBD) and irritable bowel syndromes (IBS). Additionally, evidence of hepatoprotective activities and benefits in managing metabolic syndrome and cardiovascular health issues, such as lipid metabolism regulation, cholesterol reduction, antidiabetic, antihypertensive, and immunomodulatory effects, have been observed predominantly in rodent models. Phytochemical analysis of wild thyme reveals an essential oil fraction below 1%, along with non-volatile compounds predominantly comprising phenolic acids (such as rosmarinic, salvianolic, and caffeic acids) and flavonoids (mainly glucosides of luteolin, apigenin, and their derivatives). These components are believed to contribute significantly to the plant’s medicinal, nutritional, and preventive health properties. Despite promising findings, there is a need for more rigorously designed controlled clinical trials using phytochemically characterized wild thyme. The plant has an excellent safety and tolerability record. This review at the interface of nutritional/preventive health properties and as pharmacological activities highlights the current role of wild thyme in nutrition and general healthcare as well as its future potential, and also points to important gaps in the literature.

#1320 Differential microRNA expression profile in obesity-induced kidney disease driven by high-fat diet in mice

Abstract Background and Aims Obesity is one of the main causes of chronic kidney disease; however, the precise molecular mechanisms leading to the onset of kidney dysfunction in obesity-induced kidney disease (OIKD) remain unclear. MicroRNAs (miRNAs) have been implicated in the development and progression of obesity, and several candidates have been identified as critical regulators of adipogenesis and lipid metabolism, while their dysregulation contribute to obesity-related metabolic abnormalities. The aim of the present study was to decipher the kidney microRNA (miRNA) expression profile in a mouse model of obesity-induced kidney disease characterized by systemic metabolic disturbances and kidney injury that closely resemble those observed in human disease. Method Male C57BL/6J mice were randomly divided and placed either a standard diet (STD) or a high fat diet (HFD) for 10 weeks. Serum triglycerides and total, HDL and LDL cholesterol were determined by standard clinical methods. In the kidney sections, histopathological assessments were done by using PAS and Oil-Red-O staining's. Expression of renal MCP1, TNFα, α-SMA, Fibronectin, miR-146a, miR-551b and miR-5099 was assessed by real time PCR. In order to elucidate the role of differentially expressed miRNAs, a search for target genes was done using an online computational resource DIANA-miRPath v4.0. Results High fat diet (HFD)-induced obesity led to evident structural alterations in tubular and glomerular regions of the kidney, increased renal expression of adiposity-related proinflammatory and profibrotic genes, as well as an elevated renal expression of genes involved in cellular lipid metabolism. The miRNA sequencing analysis identified a set of 9 miRNAs differentially expressed in the kidney upon HFD feeding, with miR-5099, miR-551b-3p, miR-223-3p, miR-146a-3p and miR-21a-3p showing most significant differential expression between standard diet (STD) and HFD mice. Consistently, Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Ontology (GO) enrichment analyses revealed that 3 validated miRNAs (miR-5099, miR-551b-3p and miR-146a-3p) modulated target genes involved in metabolic and adipocytokine pathways, fatty acid and lipid metabolism, inflammatory, senescence and profibrotic pathways. Conclusion Our results propose that differentially expressed miRNAs play pivotal roles in the intricated pathophysiology of obesity-associated kidney disease and could potentially create novel treatment strategies to counteract the deleterious effects of obesity on kidney function.

Nitrogen availability is important for preventing catastrophic mitosis in fission yeast.

Mitosis is a crucial stage in the cell cycle, controlled by a vast network of regulators responding to multiple internal and external factors. The fission yeast Schizosaccharomyces pombe demonstrates catastrophic mitotic phenotypes due to mutations or drug treatments. One of the factors provoking catastrophic mitosis is a disturbed lipid metabolism, resulting from, for example, mutations in the acetyl-CoA/biotin carboxylase (cut6), fatty acid synthase (fas2, also known as lsd1) or transcriptional regulator of lipid metabolism (cbf11) genes, as well as treatment with inhibitors of fatty acid synthesis. It has been previously shown that mitotic fidelity in lipid metabolism mutants can be partially rescued by ammonium chloride supplementation. In this study, we demonstrate that mitotic fidelity can be improved by multiple nitrogen sources. Moreover, this improvement is not limited to lipid metabolism disturbances but also applies to a number of unrelated mitotic mutants. Interestingly, the partial rescue is not achieved by restoring the lipid metabolism state, but rather indirectly. Our results highlight a novel role for nitrogen availability in mitotic fidelity.

Regulatory effects of Astragalus membranaceus polysaccharides on lipid metabolism disorders induced by a high-fat diet in spotted sea bass (Lateolabrax maculatus)

This study evaluated the regulatory effects of Astragalus membranaceus polysaccharides (AMP) on lipid metabolism disorders induced by a high-fat diet (HFD) in spotted sea bass (Lateolabrax maculatus). Compared with the normal diets (10 % lipids), diets containing 15 % lipid levels were used as the high-fat diet (HFD). Three levels of the AMP (0.06 %, 0.08 %, 0.10 %) were added in the HFD and used as experimental diets. A total of 375 spotted sea bass (average weight 3.00 ± 0.01 g) were divided into 15 tanks and deemed as 5 groups, with each tank containing 25 fish. Fish in each group were fed with different diets for 56 days. After feeding, the HFD induced lipid metabolism disorders in fish, as evidenced by elevated serum lipids, malonaldehyde levels, and more severe liver damage. The AMP alleviated the HFD-induced liver damage, as evidenced by the reduced severity of liver histological lesions and malonaldehyde levels. The low-density lipoprotein cholesterol was reduced, and the expression of FAS and PPAR-α were down and up-regulated, respectively. However, the AMP had a limited ability to affect the serum lipids and abdominal fat percentage. These results reveal the potential of the AMP used in aquaculture to regulate lipid metabolism disorders induced by the HFD.

Tartaric acid ameliorates experimental non-alcoholic fatty liver disease by activating the AMP-activated protein kinase signaling pathway

Tartaric acid (TA) has been shown beneficial effects on blood pressure and lipid levels. However, its effect on non-alcoholic fatty liver disease (NAFLD) remains unknown. This study aimed to investigate the role of TA in experimental NAFLD. Mice were fed a Western diet for 8 weeks, followed by administration of TA or a vehicle for an additional 12 weeks while continuing on the Western diet. Blood biochemistry including transaminases and glucose tolerance test and liver tissue RNA sequencing (RNA-seq), lipid content, and histology were investigated. The HepG2 cell line was used to explore the mechanism by which TA regulates lipid metabolism. We found that TA significantly improved weight gain, insulin resistance, hepatic steatosis, inflammation and fibrosis in Western diet-fed mice. By comparing gene expression differences, we found that TA affects pathways related to lipid metabolism, inflammatory response, and fibrosis. Furthermore, TA effectively reduced oleic acid-induced lipid accumulation in HepG2 cells and downregulated the genes associated with fatty acid synthesis, which were enriched in the AMP-activated protein kinase (AMPK) signaling pathway. TA also enhanced the phosphorylation of AMPK which could be reverted by the AMPK inhibitor Compound C in HepG2 cells. Our study suggests that TA improves experimental NAFLD by activating the AMPK signaling pathway. These findings indicate that TA may serve as a potential therapy for the human NAFLD.

#2743 Impact of fatty acid-binding protein 4 on SUMOylation balance and renal tubular epithelial cell senescence in acute kidney injury

Abstract Background and Aims Dysregulated lipid metabolism and cellular senescence intricately interact in the context of acute kidney injury (AKI). Fatty acid-binding protein 4 (FABP4), a critical enzyme regulating lipid metabolism, potentially induces cell senescence through lipotoxicity in AKI. However, the specific mechanisms remain unclear. Method We established an ischemia-reperfusion-induced AKI (IRI-AKI) model in C57 mice and quantified and localized FABP4 expression in renal tissues using Western blotting (WB), qPCR, and immunofluorescence (IF). Oil Red O staining and beta-galactosidase staining were employed to assess lipid deposition and cellular senescence in tubular cells. The same measurements were repeated in IRI-AKI by knocking out Fabp4. Additionally, bulk mRNA sequencing and single-cell sequencing were conducted on renal tissues to analyze key molecules and related mechanisms. Results In vivo, we observed a significant decline in renal function, severe tubular epithelial damage, and abundant inflammation in the IRI-AKI group, which was noticeably alleviated in the Fabp4 knockout group (Fig. 1). Furthermore, we detected upregulation of FABP4 expression in the kidneys of IRI-AKI, primarily localized in the tubular epithelial cells. Fabp4 knockout effectively reduced tubular lipid accumulation and cellular senescence (Fig. 3). Through integrating mRNA and single-cell sequencing data, UBC9, an E2 enzyme involved in protein SUMOylation, emerged as a potential key regulator of cell senescence and AKI. WB and qPCR both confirmed the upregulation of UBC9 expression in IRI-AKI and its downregulation after Fabp4 knockout. Conversely, we observed that downregulated SUMOylation in IRI-AKI was upregulated in the Fabp4 knockout group (Fig. 4). Conclusion In conclusion, FABP4 modulates the expression of UBC9 and SUMOylation, thereby mediating cellular senescence and causing renal tubular cell damage in IRI-AKI. The mechanisms underlying FABP4’s regulation of UBC9 and the opposing trend between UBC9 and SUMOylation require further elucidation.

Integrated re-analysis of transcriptomic and proteomic datasets reveals potential mechanisms for Zika viral-based oncolytic therapy in neuroblastoma.

Paediatric neuroblastoma and brain tumours account for a third of all childhood cancer-related mortality. High-risk neuroblastoma is highly aggressive and survival is poor despite intensive multi-modal therapies with significant toxicity. Novel therapies are desperately needed. The Zika virus (ZIKV) can access the nervous system and there is growing interest in employing ZIKV as a potential therapy against paediatric nervous system tumours, including neuroblastoma. Here, we perform extensive data mining, integration and re-analysis of ZIKV infection datasets to highlight molecular mechanisms that may govern the oncolytic response in neuroblastoma cells. We collate infection data of multiple neuroblastoma cell lines by different ZIKV strains from a body of published literature to inform the susceptibility of neuroblastoma to the ZIKV oncolytic response. Integrating published transcriptomics, interaction proteomics, dependency factor and compound datasets we propose the involvement of multiple host systems during ZIKV infection. Through data mining of published literature, we observed most paediatric neuroblastoma cell lines to be highly susceptible to ZIKV infection and propose the PRVABC59 ZIKV strain to be the most promising candidate for neuroblastoma oncolytic virotherapy. ZIKV induces TNF signalling, lipid metabolism, the Unfolded Protein Response (UPR), and downregulates cell cycle and DNA replication processes. ZIKV infection is dependent on sterol regulatory element binding protein (SREBP)-regulated lipid metabolism and three protein complexes; V-ATPase, ER Membrane Protein Complex (EMC) and mammalian translocon. We propose ZIKV non-structural protein 4B (NS4B) as a likely mediator of ZIKVs interaction with IRE1-mediated UPR, lipid metabolism and mammalian translocon. Our work provides a significant understanding of ZIKV infection in neuroblastoma cells, which will facilitate the progression of ZIKV-based oncolytic virotherapy through pre-clinical research and clinical trials.

Glycolytic enzyme PFKL governs lipolysis by promoting lipid droplet-mitochondria tethering to enhance β-oxidation and tumor cell proliferation.

Lipid droplet tethering with mitochondria for fatty acid oxidation is critical for tumor cells to counteract energy stress. However, the underlying mechanism remains unclear. Here, we demonstrate that glucose deprivation induces phosphorylation of the glycolytic enzyme phosphofructokinase, liver type (PFKL), reducing its activity and favoring its interaction with perilipin 2 (PLIN2). On lipid droplets, PFKL acts as a protein kinase and phosphorylates PLIN2 to promote the binding of PLIN2 to carnitine palmitoyltransferase 1A (CPT1A). This results in the tethering of lipid droplets and mitochondria and the recruitment of adipose triglyceride lipase to the lipid droplet-mitochondria tethering regions to engage lipid mobilization. Interfering with this cascade inhibits tumor cell proliferation, promotes apoptosis and blunts liver tumor growth in male mice. These results reveal that energy stress confers a moonlight function to PFKL as a protein kinase to tether lipid droplets with mitochondria and highlight the crucial role of PFKL in the integrated regulation of glycolysis, lipid metabolism and mitochondrial oxidation.

The Effect of Ovariectomy and Estradiol Substitution on the Metabolic Parameters and Transcriptomic Profile of Adipose Tissue in a Prediabetic Model.

Menopause brings about profound physiological changes, including the acceleration of insulin resistance and other abnormalities, in which adipose tissue can play a significant role. This study analyzed the effect of ovariectomy and estradiol substitution on the metabolic parameters and transcriptomic profile of adipose tissue in prediabetic females of hereditary hypertriglyceridemic rats (HHTgs). The HHTgs underwent ovariectomy (OVX) or sham surgery (SHAM), and half of the OVX group received 17β-estradiol (OVX+E2) post-surgery. Ovariectomy resulted in weight gain, an impaired glucose tolerance, ectopic triglyceride (TG) deposition, and insulin resistance exemplified by impaired glycogenesis and lipogenesis. Estradiol alleviated some of the disorders associated with ovariectomy; in particular, it improved insulin sensitivity and reduced TG deposition. A transcriptomic analysis of perimetrial adipose tissue revealed 809 differentially expressed transcripts in the OVX vs. SHAM groups, mostly pertaining to the regulation of lipid and glucose metabolism, and oxidative stress. Estradiol substitution affected 1049 transcripts with overrepresentation in the signaling pathways of lipid metabolism. The principal component and hierarchical clustering analyses of transcriptome shifts corroborated the metabolic data, showing a closer resemblance between the OVX+E2 and SHAM groups compared to the OVX group. Changes in the adipose tissue transcriptome may contribute to metabolic abnormalities accompanying ovariectomy-induced menopause in HHTg females. Estradiol substitution may partially mitigate some of these disorders.

Augmenter of liver regeneration knockout aggravates tubular ferroptosis and macrophage activation by regulating carnitine palmitoyltransferase-1A-induced lipid metabolism in diabetic nephropathy.

Ferroptosis is a novel type of programmed cell death that performs a critical function in diabetic nephropathy (DN). Augmenter of liver regeneration (ALR) exists in the inner membrane of mitochondria, and inhibits inflammation, apoptosis, and oxidative stress in acute kidney injury; however, its role in DN remains unexplored. Here, we aimed to identify the role of ALR in ferroptosis induction and macrophage activation in DN. The expression of ALR was examined in DN patients, db/db DN mice, and HK-2 cells treated with high glucose (HG). The effects of ALR on ferroptosis and macrophage activation were investigated with ALR conditional knockout, lentivirus transfection, transmission electron microscopy, qRT-PCR and western blotting assay. Mass spectrometry and rescue experiments were conducted to determine the mechanism of ALR. ALR expression was reduced in the kidney tissues of DN patients and mice, serum of DN patients, and HG-HK-2 cells. Moreover, the inhibition of ALR promoted ferroptosis, macrophage activation, and DN progression. Mechanistically, ALR can directly bind to carnitine palmitoyltransferase-1A (CPT1A), the key rate-limiting enzyme of fatty acid oxidation (FAO), and inhibit the expression of CPT1A to regulate lipid metabolism involving FAO and lipid droplet-mitochondrial coupling in DN. Taken together, our findings revealed a crucial protective role of ALR in ferroptosis induction and macrophage activation in DN and identified it as an alternative diagnostic marker and therapeutic target for DN.

Nardosinone relieves metabolic-associated fatty liver disease and promotes energy metabolism through targeting CYP2D6

BackgroundNardosinone, a major extract of Rhizoma nardostachyos, plays a vital role in sedation, neural stem cell proliferation, and protection of the heart muscle. However, the huge potential of nardosinone in regulating lipid metabolism and gut microbiota has not been reported, and its potential mechanism has not been studied. PurposeTo explore the regulation of nardosinone on liver lipid metabolism and gut microbiota. MethodsIn this study, the role of nardosinone in lipid metabolism was investigated in vitro and in vivo by adding it to mouse feed and HepG2 cell culture medium. And 16S rRNA gene sequencing was used to explore its regulatory effect on gut microbiota. ResultsResults showed that nardosinone could improve HFD-induced liver injury and abnormal lipid metabolism by promoting mitochondrial energy metabolism in hepatocytes, alleviating oxidative stress damage, and regulating the composition of the gut microbiota. Mechanistically, combined with network pharmacology and reverse docking analysis, it was predicted that CYP2D6 was the target of nardosinone, and the binding was verified by cellular thermal shift assay (CETSA). ConclusionsThis study highlights a novel mechanism function of nardosinone in regulating lipid metabolism and gut microbiota. It also predicts and validates CYP2D6 as a previously unknown regulatory target, which provides new possibilities for the application of nardosinone and the treatment of metabolic-associated fatty liver disease.