Lipid Accumulation In Liver Tissue Research Articles

Oct-B: A derivative of L-BAIBA significantly alleviating high-fat diet-induced obesity in mice

The rising prevalence of obesity is a global health concern. Supplementation with (S)-β-aminoisobutyric acid (L-BAIBA) has shown potential in preventing obesity and related metabolic disorders induced by high-fat diets. However, developing effective and low-toxicity BAIBA derivatives remains a challenging yet promising field. In this study, we introduce Oct-B, a novel BAIBA ester compound, which exhibits 80-fold greater efficacy than L-BAIBA in alleviating obesity in high-fat diet-fed mice. Our results demonstrate that Oct-B significantly reduces serum TG, TC, LDL-C, and the activities of ALT and AST, and also reduces TG and TC in liver, surpassing the effects of L-BAIBA. Histological analysis shows that Oct-B significantly decreases lipid accumulation in liver tissues, normalizes mast cells in white adipose tissue, and upregulates the expression of UCP1 protein in white adipose tissue. The qRT-PCR results indicated Oct-B alleviates obesity by downregulating lipogenic genes (PPARγ, ACC1, FAS), upregulating lipolysis related genes (PPARα, HSL) and thermogenic gene UCP1. Additionally, quantitative mass spectrometry reveals a marked increase in L-BAIBA levels in white fat, brown fat, serum, and muscle following Oct-B administration. These findings suggest that Oct-B is an efficient L-BAIBA substitute, offering a promising therapeutic approach for preventing and treating high-fat diet-induced obesity.

IL6 Derived from Macrophages under Intermittent Hypoxia Exacerbates NAFLD by Promoting Ferroptosis via MARCH3-Led Ubiquitylation of GPX4.

Obstructive sleep apnea (OSA) is a common sleep disorder characterized by intermittent hypoxia (IH) and is associated with the occurrence and development of nonalcoholic fatty liver disease (NAFLD). However, the specific mechanism by which OSA induces NAFLD remains unclear. Therefore, effective interventions are lacking. This study aims to investigate the role and mechanism of ferroptosis in OSA-related NAFLD using clinical data analyses, cell-based molecular experiments, and animal experiments. Indicators of liver function, lipid accumulation, and ferroptosis are also examined. RNA-seq, qPCR, western blotting, gene intervention, and E3 ligase prediction using UbiBrowser and co-IP are used to explore the potential underlying mechanisms. The results show that ferroptosis increases in the liver tissues of patients with OSA. Chronic IH promotes NAFLD progression in mice and is alleviated by a ferroptosis inhibitor Fer-1. The increased secretion of IL6 by macrophages can promote the expression of MARCH3 in hepatocytes under intermittent conditions, and subsequently promote the ubiquitination and degradation of GPX4 to regulate ferroptosis and lipid accumulation in hepatocytes. Hence, targeted inhibition of MARCH3 may alleviate IH-induced ferroptosis and lipid accumulation in liver tissues and inhibit the progression of NAFLD.

Bone Marrow Mesenchymal Stem Cell-Derived Nanovesicles Containing H8 Improve Hepatic Glucose and Lipid Metabolism and Exert Ameliorative Effects in Type 2 Diabetes.

Nanovesicles (NVs) derived from bone mesenchymal stem cells (BMSCs) as drug delivery systems are considered an effective therapeutic strategy for diabetes. However, its mechanism of action remains unclear. Here, we evaluated the efficacy and molecular mechanism of BMSC-derived NVs carrying the curcumin analog H8 (H8-BMSCs-NVs) on hepatic glucose and lipid metabolism in type 2 diabetes (T2D). Mouse BMSCs were isolated by collagenase digestion and H8-BMSCs-NVs were prepared by microvesicle extrusion. The effects of H8-BMSCs-NVs on hepatic glucose and lipid metabolism were observed in a T2D mouse model and a HepG2 cell insulin resistance model. To evaluate changes in potential signaling pathways, the PI3K/AKT/AMPK signaling pathway and expression levels of G6P and PEPCK were assessed by Western blotting. H8-BMSCs-NVs effectively improved lipid accumulation in liver tissues and restored liver dysfunction in T2D mice. Meanwhile, H8-BMSCs-NVs effectively inhibited intracellular lipid accumulation in the insulin resistance models of HepG2 cells. Mechanistic studies showed that H8-BMSCs-NVs activated the PI3K/AKT/AMPK signaling pathway and decreased the expression levels of G6P and PEPCK. These findings demonstrate that H8-BMSCs-NVs improved hepatic glucose and lipid metabolism in T2D mice by activating the PI3K/AKT/AMPK signaling pathway, which provides novel evidence suggesting the potential of H8-BMSCs-NVs in the clinically treatment of T2D patients.

A sport supplement candidate of Erigeron breviscapus extract regulates lipogenesis in vitro and in vivo.

One of the urgent research projects in exercise science should focus on sports supplements for obese people who lack exercise and physical activity. In this study, we explored the efficacy in non-alcoholic fatty liver disease (NAFLD) mice models using a Korean herbal medicine Erigeron breviscapus (EB). Gene ontology analyses of active compounds in EB were performed using the Traditional Chinese Medicine Database and Analysis Platform (TCMSP) and Cytoscape program, respectively. PA-induced acid (PA) induced-lipid droplets in HepG2 cells were analyzed using a 3D-hologram. To analyze the fat-suppressing efficacy of EB in animal experiments, NAFLD was induced through a 24-week high-fat diet. Subsequently, the same diet was continued for an additional 8 weeks, with concurrent co-administration of drugs for efficacy analysis. In the 8-week experiment, mice were administered saline alone, metformin (17 mg/kg/day), or EB (26 mg/kg/day). The mice were sacrificed and the liver tissue was isolated. The liver tissues were stained with H&E and specific antibodies such as sterol regulatory element binding protein 1 (SREBP-1) and peroxisome proliferator-activated receptor- γ (PPAR-γ). Seventeen EB-active compounds were identified by whole-body analysis. EB downregulated lipid droplets in PA-treated HepG2 cells. EB regulates lipid accumulation in liver tissue of HFD-fed NAFLD mice Metformin and EB significantly reduced the expression of SREBP-1 and PPAR-γ in liver tissue. We suggest that EB is a candidate for the management of NAFLD and is an effective exercise supplement owing to its ability to inhibit lipid accumulation.

Long term survival and abnormal liver fat accumulation in mice with specific thymidine kinase 2 deficiency in liver tissue.

Deficiency in thymidine kinase 2 (TK2) causes mitochondrial DNA depletion. Liver mitochondria are severely affected in Tk2 complete knockout models and have been suggested to play a role in the pathogenesis of the Tk2 knockout phenotype, characterized by loss of hypodermal fat tissue, growth retardation and reduced life span. Here we report a liver specific Tk2 knockout (KO) model to further study mechanisms contributing to the phenotypic changes associated with Tk2 deficiency. Interestingly, the liver specific Tk2 KO mice had a normal life span despite a much lower mtDNA level in liver tissue. Mitochondrial DNA encoded peptide COXI did not differ between the Tk2 KO and control mice. However, the relative liver weight was significantly increased in the male Tk2 KO mouse model. Histology analysis indicated an increased lipid accumulation. We conclude that other enzyme activities can partly compensate Tk2 deficiency to maintain mtDNA at a low but stable level throughout the life span of the liver specific Tk2 KO mice. The lower level of mtDNA was sufficient for survival but led to an abnormal lipid accumulation in liver tissue.

Pancreastatin deteriorates hepatic lipid metabolism via elevating fetuin B in ovariectomized rats

Hepatic steatosis is an important mstetabolic complication in women encountering postmenopausal phase of life. Pancreastatin (PST), has previously been investigated in diabetic and insulin resistant rodents. The present study highlighted the role of PST in ovariectomized rats. Female SD rats were ovariectomized and subsequently fed high fructose diet for 12 weeks. PST inhibitor peptide was intraperitoneally administered for 14 days and further examined for insulin resistance, glucose intolerance development, body mass composition, lipid profile detection and hepatic fibrosis. Gut microbial alterations has also been investigated. Results showed development of glucose intolerance in high fructose fed ovariectomized rats with reduced level of reproductive hormones including estradiol and progesterone. Enhanced lipid production was detected in these rats as they showed increased triglycerides, lipid accumulation in liver tissue (determined by HE staining, Oil Red O staining, Nile Red staining). Sirius Red and Masson's trichome analysis depicted positive results for fibrosis development. We also found gut microbiota alterations in fecal samples of these rats. Furthermore, PST inhibition decreased the expression of hepatic Fetuin B and resumed gut microbial diversity. PST deregulates hepatic lipid metabolism which leads to altered expression of Fetuin B in liver and gut dysbiosis in postmenopausal rats.

Inhibition of phospholipase D1 ameliorates hepatocyte steatosis and non-alcoholic fatty liver disease

Background & AimsPhospholipase D1 (PLD1), a phosphatidylcholine-hydrolysing enzyme, is involved in cellular lipid metabolism. However, its involvement in hepatocyte lipid metabolism and consequently non-alcoholic fatty liver disease (NAFLD) has not been explicitly explored. MethodsNAFLD was induced in hepatocyte-specific Pld1 knockout (Pld1(H)-KO) and littermate Pld1flox/flox (Pld1-Flox) control mice feeding a high-fat diet (HFD) for 20 wk. Changes of the lipid composition in the liver were compared. Alpha mouse liver 12 (AML12) cells and mouse primary hepatocytes were incubated with oleic acid or sodium palmitate in vitro to explore the role of PLD1 in the development of hepatic steatosis. Hepatic PLD1 expression was evaluated in liver biopsy samples in patients with NAFLD. ResultsPLD1 expression levels were increased in the hepatocytes of patients with NAFLD and HFD-fed mice. Compared with Pld1-Flox mice, Pld1(H)-KO mice exhibited decreased plasma glucose and lipid levels as well as lipid accumulation in liver tissues after HFD feeding. Transcriptomic analysis showed that hepatocyte-specific deficiency of PLD1 decreased Cd36 expression in steatosis liver tissues, which was confirmed at the protein and gene levels. In vitro, specific inhibition of PLD1 with VU0155069 or VU0359595 decreased CD36 expression and lipid accumulation in oleic acid- or sodium palmitate-treated AML12 cells or primary hepatocytes. Inhibition of hepatocyte PLD1 significantly altered lipid composition, especially phosphatidic acid and lysophosphatidic acid levels in liver tissues with hepatic steatosis. Furthermore, phosphatidic acid, the downstream product of PLD1, increased the expression levels of CD36 in AML12 cells, which was reversed by a PPARγ antagonist. ConclusionsHepatocyte-specific Pld1 deficiency ameliorates lipid accumulation and NAFLD development by inhibiting the PPARγ/CD36 pathway. PLD1 may be a new target for the treatment of NAFLD. Impact and implicationsThe involvement of PLD1 in hepatocyte lipid metabolism and NAFLD has not been explicitly explored. In this study, we found that the inhibition of hepatocyte PLD1 exerted potent protective effects against HFD-induced NAFLD, which were attributable to a reduction in PPARγ/CD36 pathway-mediated lipid accumulation in hepatocytes. Targeting hepatocyte PLD1 may be a new target for the treatment of NAFLD.

Effects of Cichorium glandulosum on hyperglycemia, dyslipidemia and intestinal flora in db/db mice

• Study on the hypoglycemic and lipid-lowering effects of Chicory on db/db mice. • Effect of Chicory on db/db intestinal flora. • Relationship between intestinal flora and insulin resistance, short chain fatty acids. This study aimed to investigate the effects of Cichorum glandulosum Boiss. et Huet. whole herb extract (CG) on hypoglycemic, lipidemic effects, and intestinal flora in db/db mice. The experimental results showed that CG orally administered to db/db mice had specific hypoglycemic activity. CG could effectively alleviate the lipid accumulation in liver tissues,improve the antioxidant capacity and thus liver injury in db/db mice. In addition, CG treatment can activate uncoupling protein ( UCP-1 ) and improve the dysbiosis in the intestine. These findings suggest that CG has particular hypoglycemic activity, can improve blood lipid and intestinal flora disorders in db/db mice, reduce Firmicutes/Bacteroide , by affecting the gut-fat axis, promote the process of white fat browning in db/db mice, thus reducing insulin resistance in the body, and can be used for the prevention and treatment of type 2 diabetes.

Arctiin attenuates lipid accumulation, inflammation and oxidative stress in nonalcoholic fatty liver disease through inhibiting MAPK pathway

Nonalcoholic fatty liver disease (NAFLD) is a common chronic liver disease that predominantly affects the adult population. It was reported that arctiin improves functioning of the liver through multiple pathways, but the exact molecular mechanism is not clear yet. First, a mouse obesity model was successfully constructed, and hematoxylin and eosin staining and enzyme-linked-immunosorbent serologic assay (ELISA) were used to assess the levels of alanine aminotransferase and aspartate aminotransferase, respectively, in liver tissue damage. Then lipid accumulation in liver tissues was detected by immunohistochemistry (IHC) staining, and detection kits were used to determine the levels of triglycerides and total cholesterol in serum. Western blotting was used to detect the expression of adipose synthesis proteins, sterol regulatory element-binding protein-1, stearoyl-CoA desaturase-1 and fatty acid synthase, in liver tissues. Further, the levels of glutathione peroxidase, malondialdehyde, superoxide dismutase, catalase and reactive oxygen species as well as that of interleukin 2 (IL-2), IL-1β, IL-6 and tumor necrosis factor-α, and the expression of p-P65 and P65, in liver tissues were measured by ELISA and IHC, respectively. Finally, the protein expression levels of extracellular signal-regulated kinase (ERK), phospho-ERK, Jun N-terminal kinase, phospho-JNK, p38 and phospho-p38 in liver tissues were examined by WB. The results showed that relative to normal diet, mice on high-fat diet had increased body weight as well as fat content in liver tissues, increased liver tissue damage, decreased oxidative stress capacity and enhanced inflammatory response, while arctiin changed these adverse effects and inhibited mitogen-activated protein kinase (MAPK) pathway. Arctiin exerts hepatoprotective effects by inhibiting MAPK pathway and improving lipid accumulation, inflammatory response and oxidative stress.

Effect of Lentinus Edodes Mycelial Culture on Blood and Hepatic Steatosis of High-fed Diet Mice

This study attempted to investigate the influence of a high-fat diet (HFD) on body weight, food efficiency ratio (FER), liver weight, blood composition and liver tissues. For this, it was divided into Normal, HFD/Control and HFD/MC-LE (360 mg/kg), and the experiment was performed over ten (10) weeks. Compared to HFD/Control, body weight decreased when HFD/MC-LE was administered. In addition, TG and AST blood concentration improved with HFD/MC-LE. In terms of celiac disease in liver tissues, hepatic sinusoids were closed due to the accumulation of adipose tissues. Furthermore, hepatocyte cords in a hepatic lobule and lipid accumulation in liver tissues were confirmed. In the liver tissues of HFD/MC-LE-administered mice, lipid accumulation decreased, and liver tissue damage was minor. The above results show that HFD/MC-LE is more effective than HFD/Control in reducing body weight, composing blood, preventing liver tissue damage and decreasing lipid accumulation in liver tissues confirming its possibility as a sub-ingredient for fatty liver treatment.

Purendan alleviates non-alcoholic fatty liver disease in aged type 2 diabetic rats via regulating mTOR/S6K1/SREBP-1c signaling pathway

Older people are more likely to develop insulin resistance and lipid metabolism disorders. Purendan (PRD) is a clinically verified traditional Chinese medicine compound, which plays an obvious role in regulating lipid metabolism disorder and improving insulin sensitivity. Our study aimed to investigate the efficacy and mechanism of PRD on aged type 2 diabetes mellitus (T2DM) complicated with non-alcoholic fatty liver disease (NAFLD) rats. Sprague-Dawley rats (13 months) were fed with high-fat diet (HFD) and injected with low-dose STZ to replicate T2DM model. PRD was treated at three concentrations with metformin as a positive control. After administration, blood and liver tissue samples were collected to measure glucose metabolism indexes such as serum glucose and insulin, as well as lipid metabolism indexes such as TC, TG, LDL, HDL and FFA. Liver fat accumulation was observed by HE staining and oil red O staining. And protein expression levels of mTOR, p-mTOR, S6K1, p-S6K1 and SREBP-1c were detected by western blot. After PRD treatment, not only the insulin sensitivity and insulin resistance were significantly improved, but also the TC, TG, LDL, FFA, AST and ALT in serum and the lipid accumulation in liver tissue were significantly decreased. Moreover, PRD significantly down-regulated the expression of p-mTOR, p-S6K1 and SREBP-1c in liver tissues. In conclusion, PRD can alleviate NAFLD in aged T2DM rats by inhibiting the mTOR /S6K1/ SREBP-1c pathway.

RMRP inhibition prevents NAFLD progression in rats via regulating miR-206/PTPN1 axis.

This study aimed to investigate the regulatory function of lncRNA RMRP in non-alcoholic fatty liver disease (NAFLD). In vitro and in vivo NAFLD models were constructed. Hematoxylin & Eosin (H&E) and Oil-Red O staining assays were conducted to observe the morphology and lipid accumulation in liver tissues. Triglycine (TG) secretion was detected by ELISA assay. The expression levels of RMRP, microRNA-206, PTPN1 (protein tyrosine phosphatase, non-receptor type 1), and their downstream genes were assessed by qRT-PCR and Western blot. The regulatory relationship among these molecules was determined by luciferase reporter and RNA pull-down assays. RMRP and PTPN1 were up-regulated, while miR-206 was down-regulated in the liver tissues of NAFLD patients and rat model. RMRP inhibition improved the pathological state and liver function-related indexes of liver lipid deposition in the liver tissues of NAFLD rats. RMRP inhibition alleviated steatosis and TG secretion in free fatty acids (FFA)-treated AML-12 cells. RMRP could bind to miR-206 and downregulate its expression. Meanwhile, RMRP inhibition attenuated lipid accumulation by downregulating the PTPN1-PP2ASP1-SREBP1C pathway. Furthermore, RMRP inhibited the miR-206/PTPN1-SREBP1C signaling pathway in NAFLD rats and FFA-treated AML-12 cells. RMRP inhibition prevented NAFLD progression in rats via targeting the miR-206/PTPN1 axis.

Lipotoxicity-induced STING1 activation stimulates MTORC1 and restricts hepatic lipophagy

ABSTRACT Lipid accumulation often leads to lipotoxic injuries to hepatocytes, which can cause nonalcoholic steatohepatitis. The association of inflammation with lipid accumulation in liver tissue has been studied for decades; however, key mechanisms have been identified only recently. In particular, it is still unknown how hepatic inflammation regulates lipid metabolism in hepatocytes. Herein, we found that PA treatment or direct stimulation of STING1 promoted, whereas STING1 deficiency impaired, MTORC1 activation, suggesting that STING1 is involved in PA-induced MTORC1 activation. Mechanistic studies revealed that STING1 interacted with several components of the MTORC1 complex and played an important role in the complex formation of MTORC1 under PA treatment. The involvement of STING1 in MTORC1 activation was dependent on SQSTM1, a key regulator of the MTORC1 pathway. In SQSTM1-deficient cells, the interaction of STING1 with the components of MTORC1 was weak. Furthermore, the impaired activity of MTORC1 via rapamycin treatment or STING1 deficiency decreased the numbers of LDs in cells. PA treatment inhibited lipophagy, which was not observed in STING1-deficient cells or rapamycin-treated cells. Restoration of MTORC1 activity via treatment with amino acids blocked lipophagy and LDs degradation. Finally, increased MTORC1 activation concomitant with STING1 activation was observed in liver tissues of nonalcoholic fatty liver disease patients, which provided clinical evidence for the involvement of STING1 in MTORC1 activation. In summary, we identified a novel regulatory loop of STING1-MTORC1 and explain how hepatic inflammation regulates lipid accumulation. Our findings may facilitate the development of new strategies for clinical treatment of hepatic steatosis. Abbreviations: AA: amino acid; ACTB: actin beta; cGAMP: cyclic GMP-AMP; CGAS: cyclic GMP-AMP synthase; DEPTOR: DEP domain containing MTOR interacting protein; EIF4EBP1: eukaryotic translation initiation factor 4E binding protein 1; FFAs: free fatty acids; GFP: green fluorescent protein; HFD: high-fat diet; HT-DNA: herring testis DNA; IL1B: interleukin 1 beta; LAMP1: lysosomal associated membrane protein 1; LDs: lipid droplets; MAP1LC3: microtubule associated protein 1 light chain 3; MAP1LC3B: microtubule associated protein 1 light chain 3 beta; MEFs: mouse embryonic fibroblasts; MLST8: MTOR associated protein, LST8 homolog; MT-ND1: mitochondrially encoded NADH: ubiquinone oxidoreductase core subunit 1; mtDNA: mitochondrial DNA; MTOR: mechanistic target of rapamycin kinase; MTORC1: MTOR complex 1; NAFL: nonalcoholic fatty liver; NAFLD: nonalcoholic fatty liver disease; NASH: nonalcoholic steatohepatitis; NPCs: non-parenchymal cells; PA: palmitic acid; PLIN2: perilipin 2; RD: regular diet; RELA: RELA proto-oncogene, NF-kB subunit; RPS6: ribosomal protein S6; RPS6KB1: ribosomal protein S6 kinase B1; RPTOR: regulatory associated protein of MTOR complex 1; RRAGA: Ras related GTP binding A; RRAGC: Ras related GTP binding C; SQSTM1: sequestosome 1; STING1: stimulator of interferon response cGAMP interactor 1; TBK1: TANK binding kinase 1; TGs: triglycerides; TREX1: three prime repair exonuclease 1.

Oyster hydrolysate ameliorates ethanol diet‐induced alcoholic fatty liver by regulating lipid metabolism in rats

SummaryWe evaluated the effect of oyster hydrolysate, which was prepared using transglutaminase, protamex and neutrase (TGPN), on alcoholic fatty liver. Sprague–Dawley rats were fed a diet containing 5% (v/v) ethanol or an isocaloric amount of dextrin–maltose for 6 weeks and orally administered TGPN or silymarin for another 4 weeks. TGPN significantly decreased the liver index (liver weight/body weight), serum and hepatic lipid levels and increased the serum adiponectin level. Based on histological analysis, TGPN reduced the number of lipid droplets and lipid accumulation in liver tissue. TGPN enhanced the expression of AMP‐activated protein kinase and activated its downstream pathway which controls lipid metabolism. Additionally, TGPN decreased the levels of liver function markers (aspartate aminotransferase and alanine aminotransferase) and tumour necrosis factor alpha. Consequently, TGPN ameliorated alcoholic fatty liver by inhibiting fatty acid and cholesterol synthesis, promoting fatty acid oxidation and decreasing liver cell damage.

Study on lipid-lowering mechanism of active peptide DP17 from Eupolyphaga steleophaga in hyperlipidemia rats

The aim of this paper was to investigate the mechanism of the active peptide DP17 of Eupolyphaga steleophaga in the treatment of hyperlipidemia rats. HPLC and MADIL-TOF/TOF-MS were used for the amino acid sequence analysis and solid-phase synthesis on the active peptide of E. steleophaga which were obtained by biomimetic enzymatic hydrolysis, separation and purification. The hyperlipidemia model was established by feeding with high-fat diet.Twenty days later, the rats in the blank group and the model group were given the saline and the rats in remaining groups were given the corresponding drugs by oral administration. After administration for 4 weeks, the levels of triglyceride(TG), total cholesterol(TC) and low density lipoprotein(LDL) in serum, the levels of TG, TC, adenosine monophosphate(AMP), adenosine triphosphate(ATP) in liver tissues and TG in feces were detected, respectively. Hematoxylin-eosin(HE) staining was used to observe the pathological changes of liver tissues. The Real-time fluorescence quantitative PCR method was used to detect the expression of acetyl coa carboxylase(ACC) and hydroxymethylglutaryl-coa reductase(HMGCR) mRNA in liver tissues. The expression of mammalian target of rapamycin(mTORC1) protein and adenosine 5'-monophosphate-activated protein kinase(AMPK) in liver tissues were detected by Western blot. The analysis showed that the amino acid sequence of active peptide from E. steleophaga was DAVPGAGPAGCHPGAGP(DP17). The results of pharmacological experiments showed that after oral administration of DP17 in rats, the levels of TG, TC and LDL in serum as well as TG and TC levels in liver tissues were significantly decreased(P<0.05), while the levels of AMP, ATP in liver tissues and TG content in feces were significantly increased(P<0.05); the liver steatosis of rats was significantly relieved; the expression of ACC, HMGCR mRNA and mTORC1 protein in liver tissues were significantly reduced, while the expression of AMPK phosphorylated protein was significantly increased(P<0.05). DP17, the active peptide of E. steleophag can significantly reduce lipid accumulation in liver tissues, and it may play a role in reducing blood lipids by regulating the energy metabolism balance in the body and activating AMPK/mTOR signaling pathway.

Lacto-Fermented Cauliflower Fungus (Sparassis crispa) Ameliorates Hepatic Steatosis by Activating Beta-Oxidation in Diet-Induced Obese Zebrafish.

Sparassis crispa (SC), known as cauliflower mushroom, possesses a wide variety of health-promoting properties and a high content of β-glucans. Its nutritional properties are enhanced by fermentation. In this study, we examined the efficacy of Lactobacillus-fermented (lacto-fermented) SC against obesity using a zebrafish model. We first fermented SC by Lactobacillus paracasei, denoted as lacto-fermented SC (L-SC), for 48 h and then orally administered SC or L-SC to diet-induced obese zebrafish for 4 weeks. Results demonstrated that the L-SC group (20 μg/gBW/day) significantly (P < .01) suppressed body weight gain and ameliorated lipid accumulation in liver tissues, whereas SC did not exhibit antiobesity effects. We further performed expression analysis of genes related to lipid metabolism in the liver and visceral adipose tissues (VAT) in L-SC-administered fish. In liver tissues, L-SC upregulated (P < .05) expression of genes involved in peroxisome proliferator-activated receptor alpha pathways, suggesting that the lipid-lowering property of L-SC is caused by activation of beta-oxidation. In VAT, L-SC did not show significant changes between the experimental groups. No difference was observed between the β-glucan contents of SC (43.8 g/100 g) and L-SC (44.3 g/100 g); however, β-glucan levels in the hot-water extracts increased 20-fold in L-SC (37.2 g/100 g) compared with those in SC (1.8 g/100 g). In summary, lacto-fermentation of SC enhances its lipid-lowering property and can prevent hepatic steatosis through activation of beta-oxidation. Dietary supplementation of fermented L-SC as a functional food may be suitable for obesity prevention and reduction in the prevalence of obesity-related diseases.

Reactive Oxygen Species Induces Lipid Droplet Accumulation in HepG2 Cells by Increasing Perilipin 2 Expression.

Non-alcoholic fatty liver disease (NAFLD) has become the world’s most common liver disease. The disease can develop liver fibrosis or even carcinomas from the initial hepatic steatosis, and this process is influenced by many factors. Reactive oxygen species (ROS), as potent oxidants in cells, have been reported previously to play an important role in the development of NAFLD progression via promoting neutral lipid accumulation. Here, we found that ROS can promote lipid droplet formation in hepatocytes by promoting perilipin2 (PLIN2) expression. First, we used different concentrations of hydrogen peroxide to treat HepG2 cells and found that the number of lipid droplets in the cells increased, however also that this effect was dose-independent. Then, the mRNA level of several lipid droplet-associated genes was detected with hydrogen peroxide treatment and the expression of PLIN2, PLIN5, and FSP27 genes was significantly up-regulated (p < 0.05). We overexpressed PLIN2 in HepG2 cells and found that the lipid droplets in the cells were markedly increased. Interference with PLIN2 inhibits ROS-induced lipid droplet formation, revealing that PLIN2 is a critical factor in this process. We subsequently analyzed the regulatory pathway and protein interaction network that is involved in PLIN2 and found that PLIN2 can regulate intracellular lipid metabolism through the PPARα/RXRA and CREB/CREBBP signaling pathways. The majority of the data indicated the correlation between hydrogen peroxide-induced PLIN2 and lipid droplet upregulation. In conclusion, ROS up-regulates the expression of PLIN2 in hepatocytes, whereas PLIN2 promotes the formation of lipid droplets resulting in lipid accumulation in liver tissues.

Volatile Oil of Amomum villosum Inhibits Nonalcoholic Fatty Liver Disease via the Gut-Liver Axis.

Background The dried mature fruit of Amomum villosum has been historically used in China as food and in the auxiliary treatment of digestive system disorders. Numerous studies have shown that gastrointestinal function is closely related to the development of nonalcoholic fatty liver disease via the “gut-liver” axis. Objective The present study aimed to explore whether the mechanism underlying the regulation of lipid accumulation in nonalcoholic fatty liver disease (NAFLD) may affect related disorders using the active ingredients in A. villosum. Design Male Sprague-Dawley rats on a high-fat diet (HFD) to induce NAFLD were administered water extract of A. villosum (WEAV), volatile oil of A. villosum (VOAV), or bornyl acetate. After treatment, serum and liver total cholesterol (TC), triglyceride (TG), free fatty acid (FFA), aspartate aminotransferase (AST), alanine aminotransferase (ALT), high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C) levels were measured. The regulatory role of A. villosum in the microecology of the intestines was assessed using the V4 region of the 16S rDNA sequencing. The expression of the intestinal tight junction proteins occludin and ZO-1 was also measured. The influence of A. villosum on TLR4-mediated chronic low-grade inflammation was evaluated based on the concentrations of key proteins of the TLR4/NF-кB signaling pathway. Results. A. villosum effectively inhibited endogenous lipid synthesis, reduced TG, TC, and FFA accumulation, regulated the expression of LDL-C, and decreased lipid accumulation in liver tissues. VOAV effectively regulated the intestinal microflora, improved chronic low-grade inflammation by promoting ZO-1 and occludin protein expressions, and inhibited the TLR4/NF-кB signaling pathway. Conclusion The present study provides scientific basis for the potential application of A. villosum in NAFLD prevention and treatment. Additional chemical constituents other than bornyl acetate also contributed to the preventive effects of A. villosum on NAFLD.

PMFs-rich Citrus extract prevents the development of non-alcoholic fatty liver disease in C57BL/6J mice induced by a high-fat diet

Oxidative stress and excessive lipid accumulation in liver tissues are considered as important factors in development of non-alcoholic fatty liver disease (NAFLD), which is the most common chronic liver disease worldwide and strongly associated with insulin resistance, obesity and dyslipidemia. In this study, the effect of PMFs-enriched extract of Daoxianyeju (Citrus daoxianensis S.W. He) (EDX) on NAFLD were examined using high fat diet-induced obesity (DIO) C57BL/6 mice. Daily supplementation of 0.2% and 0.5% EDX with high fat diet (w/w) over ten weeks markedly improved glucose tolerance and insulin resistance as well as lipid profiles, alleviated hepatic steatosis, inflammatory and oxidative stress. The benefit of EDX on improving pathology of NAFLD induced by high fat diet may associate with the activation of nuclear factor erythroid-2 related factor 2 (Nrf2) pathways in liver tissues. Our study showed that citrus PMFs may use as a dietary therapy for NAFLD and related metabolic disorders.

Substance P blocks ethanol-induced hepatotoxicity

AimsExcessive alcohol consumption induces hepatic injury and promotes lipid accumulation, events involved in the pathogenesis of serious conditions such as alcoholic liver disease (ALD). Thus, protection of hepatocytes against alcohol-induced death is considered to be a critical approach to prevent development of liver disease. Substance P (SP) is capable of promoting cell proliferation and blocking cell death under diverse stresses, leading to beneficial effects in severe diseases, and is therefore likely to have a therapeutic application in hepatic injury. Main methodsTo assess its effects on ethanol-induced hepatic damage in vitro and in vivo, SP was administered to ethanol-treated hepatocytes and a mouse model of this condition, respectively. The effect of SP was assessed based on cell viability, apoptosis, and Akt/GSK-3β signaling, and mouse liver histology and serum biochemical parameters. Key findingsSP was found to prevent hepatocyte death due to ethanol-induced oxidative stress by upregulating Akt/GSK-3β activation in vitro. In vivo, ethanol treatment elevated levels of serum alanine transaminase and also increased the number of apoptotic cell, exhibiting lipid accumulation in liver tissue, effects that were entirely negated by SP treatment. Taken together, our results revealed that SP is able to block hepatic damage due to ethanol-induced oxidative stress and exerts therapeutic effects in liver disease, including ALD. Our findings identify SP treatment as a potential therapy for hepatic damage.