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ABSTRACTMetabolic dysfunction-associated steatotic liver disease (MASLD) is the most common chronic liver disease, and its prevalence has increased worldwide in recent years. Additionally, there is a close relationship between MASLD and gut microbiota-derived metabolites. However, the mechanisms of MASLD and its metabolites are still unclear. We demonstrated decreased indole-3-propionic acid (IPA) and indole-3-acetic acid (IAA) in the feces of patients with hepatic steatosis compared to healthy controls. Here, IPA and IAA administration ameliorated hepatic steatosis and inflammation in an animal model of WD-induced MASLD by suppressing the NF-κB signaling pathway through a reduction in endotoxin levels and inactivation of macrophages. Bifidobacterium bifidum metabolizes tryptophan to produce IAA, and B. bifidum effectively prevents hepatic steatosis and inflammation through the production of IAA. Our study demonstrates that IPA and IAA derived from the gut microbiota have novel preventive or therapeutic potential for MASLD treatment.

Archaeological excavations led by Yung-jo Lee and Jong-yoon Woo were carried out twice at the Sorori paleolithic site, Cheongju, in the Republic of Korea, at the upper stream of the Geumgang river, the Miho riverside. A total of 127 rice seeds were excavated, including 18 ancient rice and 109 Quasi-rice, in 1998 and 2001. At the first excavation, eleven short japonica-type ancient rice and one slender smooth ancient rice with two kinds of Quasi-rice were excavated. The average length of the 11 short rice grains obtained from the first and second excavation was 7.19 mm and the average width was 3.08 mm, respectively. The Quasi-rice are apparently different from the rice and do not have bi-peak protuberances on their glume surface. At the second excavation, six short ancient rice chaffs and some Quasi-rice 2 were found. These short-grained ancient rice were comparable to the ancient rice that were excavated at the Illsan Neolithic site. Geologists and radiologists confirmed that the peat layer in which the rice found was older than 15,000 years. In this study, the morphological characteristics, crushing, and DNA band patterns related to the genetic polymorphism of rice grains in Cheongju Sorori were compared and analyzed for genetic similarities and differences with wild rice, weed rice, and modern rice. The morphological, ecological, and physiological variations in rice grains excavated from the Sorori site were presumed to denote the origin of rice domestication in Korea. It is also suggested that the results of the DNA sequencing of excavated rice are very important clues in estimating the origin of the early domestication of rice.

ABSTRACT The human gut microbiome is engaged in biological homeostasis in the gut-liver axis and across multi-organs. The aim of this study is to investigate the therapeutic effects of human gut-derived microbes, Bacteroides species on liver cirrhosis in a mouse model. The experiment was performed on male mice, which were divided into five groups: normal control (NC), disease control, Bacteroides dorei-, Bacteroides cellulosilyticus-, and ursodeoxycholic acid-supplemented groups after 3,5-diethoxycarbonyl-1,4-dihydrocollidine treatment. The therapeutic effect was evaluated based on liver physiology and the expression level of hepatic fibrosis. Untargeted and targeted metabolic profiling was conducted on cecal, fecal, liver, and serum samples using ultra-performance liquid-chromatography coupled with high-resolution mass-spectrometry. The gut microbial taxonomic composition was analyzed by 16S rRNA gene amplicon sequencing from the stool of each mice group. The Bacteroides treatment improved the liver/body weight ratio and normalized hepatic fibrosis biomarkers, including COL1A1. The fecal metabolome showed the most distinctive and characteristic profiles according to different treatments, compared to other sample matrices (cecum, liver, and blood). Key metabolites were identified, which indicated the potential therapeutic effect of the B. dorei treatment. Among them, a short-chain fatty acid, propionic acid, showed consistent upregulation in the cecum and liver after the B. dorei treatment. Microbiome analysis showed that Akkermansia muciniphila was retained in the group treated with B. dorei at a similar level as in the NC group. Our current multiomics study of systemic dynamics demonstrated that Bacteroides species, particularly B. dorei, ameliorated liver cirrhosis by modulating the metabolic and microbial environment to the normal state within the gut-liver axis. IMPORTANCE The human gut microbiome mediates bidirectional interaction within the gut-liver axis, while liver diseases, including liver cirrhosis, are very closely related to the state of the gut environment. Thus, improving the health of the gut-liver axis by targeting the intestinal microbiota is a potential therapeutic approach in hepatic diseases. This study examines changes in metabolomics and microbiome composition by treating bacteria derived from the human gut in mice with liver cirrhosis. Interorgan-based multiomics profiling coupled with functional examination demonstrated that the treatment of Bacteroides dorei pertained to protective effects on liver cirrhosis by normalizing the functional, metabolic, and metagenomic environment through the gut-liver axis. The study provides the potential value of a multiomics-based and interorgan-targeted evaluation platform for the comprehensive examination and mechanistic understanding of a wide range of biologics, including gut microbes. Furthermore, the current finding also suggests in-depth future research focusing on the discovery and validation of next-generation probiotics and products (postbiotics).

Background: Atopic dermatitis (AD) is a prevalent inflammatory skin disorder characterized by skin barrier dysfunction, thymic stromal lymphopoietin (TSLP) production and an imbalance in the Th1/Th2 immune response. While numerous studies have examined the therapeutic potential of adipose-derived stem cells (ADSC) in repairing and regenerating damaged skin tissues caused by AD, the effects of membrane-free stem cell components derived from ADSC extract (ADSCE) on AD have not been investigated. Objectives: The objective of this study was to investigate the alleviating effects of ADSCE on AD in mice and validate the therapeutic application of ADSCE on AD. Methods: An AD-like lesion was induced by the administration of 2,4-dinitrochlorobenzene (DNCB) on the dorsal skin of NC/Nga mice. Then, ADSCE was administered subcutaneously for 3 weeks. Dermatitis score, epidermal thickness, transepidermal water loss (TEWL), and serum levels of immunoglobulin E (IgE) were measured. Expression of the skin barrier proteins and inflammatory cytokines were measured by western blotting and quantitative real-time polymerase chain reaction. Results: The administration of ADSCE demonstrated a significant amelioration in several skin diseases, as indicated by improvements in dermatitis score, epidermal thickness, TEWL, and total blood levels of IgE. ADSCE treatment led to an upregulation in the expression of various skin barrier proteins, including involucrin, loricrin, occludin, and zonula occludens-1. In addition, ADSCE inhibited the infiltration of mast cells and the expression of TSLP. Expression of inflammatory cytokines, including tumor necrosis factor-α, interleukin (IL)-1 β, IL-4, and inducible nitric oxide synthase, was also lowered by ADSCE. Conclusions: The use of ADSCE resulted in enhanced skin features and exerted anti-inflammatory properties on AD-like lesions in mice.

Emerging evidences about gut-microbial modulation have been accumulated in the treatment of nonalcoholic fatty liver disease (NAFLD). We evaluated the effect of Bifidobacterium breve and Bifidobacterium longum on the NAFLD pathology and explore the molecular mechanisms based on multi-omics approaches. Human stool analysis [healthy subjects (n = 25) and NAFLD patients (n = 32)] was performed to select NAFLD-associated microbiota. Six-week-old male C57BL/6 J mice were fed a normal chow diet (NC), Western diet (WD), and WD with B. breve (BB) or B. longum (BL; 109 CFU/g) for 8 weeks. Liver/body weight ratio, histopathology, serum/tool analysis, 16S rRNA-sequencing, and metabolites were examined and compared. The BB and BL groups showed improved liver histology and function based on liver/body ratios (WD 7.07 ± 0.75, BB 5.27 ± 0.47, and BL 4.86 ± 0.57) and NAFLD activity scores (WD 5.00 ± 0.10, BB 1.89 ± 1.45, and BL 1.90 ± 0.99; p

The ascomycete fungus Cordyceps militaris infects lepidopteran larvae and pupae and forms characteristic fruiting bodies. Owing to its immune-enhancing effects, the fungus has been used as a medicine. For industrial application, this fungus can be grown on geminated soybeans as an alternative protein source. In our study, we performed a comprehensive transcriptomic analysis to identify core gene sets during C. militaris cultivation on germinated soybeans. RNA-Seq technology was applied to the fungal cultures at seven-time points (2, 4, and 7-day and 2, 3, 5, 7-week old cultures) to investigate the global transcriptomic change. We conducted a time-series analysis using a two-step regression strategy and chose 1460 significant genes and assigned them into five clusters. Characterization of each cluster based on Gene Ontology and Kyoto Encyclopedia of Genes and Genomes databases revealed that transcription profiles changed after two weeks of incubation. Gene mapping of cordycepin biosynthesis and isoflavone modification pathways also confirmed that gene expression in the early stage of GSC cultivation is important for these metabolic pathways. Our transcriptomic analysis and selected genes provided a comprehensive molecular basis for the cultivation of C. militaris on germinated soybeans.

BackgroundCeramides are associated with metabolic complications including diabetic nephropathy in patients with diabetes. Recent studies have reported that podocytes play a pivotal role in the progression of diabetic nephropathy. Also, mitochondrial dysfunction is known to be an early event in podocyte injury. Thus, we tested the hypothesis that ceramide accumulation in podocytes induces mitochondrial damage through reactive oxygen species (ROS) production in patients with diabetic nephropathy.MethodsWe used Otsuka Long Evans Tokushima Fatty (OLETF) rats and high-fat diet (HFD)-fed mice. We fed the animals either a control- or a myriocin-containing diet to evaluate the effects of the ceramide. Also, we assessed the effects of ceramide on intracellular ROS generation and on podocyte autophagy in cultured podocytes.ResultsOLETF rats and HFD-fed mice showed albuminuria, histologic features of diabetic nephropathy, and podocyte injury, whereas myriocin treatment effectively treated these abnormalities. Cultured podocytes exposed to agents predicted to be risk factors (high glucose, high free fatty acid, and angiotensin II in combination [GFA]) showed an increase in ceramide accumulation and ROS generation in podocyte mitochondria. Pretreatment with myriocin reversed GFA-induced mitochondrial ROS generation and prevented cell death. Myriocin-pretreated cells were protected from GFA-induced disruption of mitochondrial integrity.ConclusionWe showed that mitochondrial ceramide accumulation may result in podocyte damage through ROS production. Therefore, this signaling pathway could become a pharmacological target to abate the development of diabetic kidney disease.

A novel output-feedback controller for uncertain nonautonomous nonlinear systems with unknown relative-degree is proposed in this study. With the assumption that the upper bound of the relative degree is known, the proposed control scheme is designed based on the input filter and higher-order switching differentiator(HOSD) with over dimension. Using the overestimated time-derivatives of tracking error by HOSD, the proposed controller compensates for the effects of uncertainties including an unknown relative degree in the controlled system. Assuming that the internal zero dynamics, if they exist, are stable, the asymptotic stability of the closed-loop system is guaranteed.

Sphingosine 1-phosphate (S1P) lyase is an intracellular enzyme that catalyzes the irreversible degradation of S1P and has been suggested as a therapeutic target for the treatment of psoriasis vulgaris. Because S1P induces differentiation of keratinocytes, we examined whether modulation of S1P lyase and altered intracellular S1P levels regulate proliferation and differentiation of human neonatal epidermal keratinocyte (HEKn) cells. To identify the physiological functions of S1P lyase in skin, we inhibited S1P lyase in HEKn cells with an S1P lyase-specific inhibitor (SLI) and with S1P lyase 1 (SGPL1)-specific siRNA (siSGPL1). In HEKn cells, pharmacological treatment with the SLI caused G1 arrest by upregulation of p21 and p27 and induced keratin 1, an early differentiation marker. Similarly, genetic suppression by siSGPL1 arrested the cell cycle at the G1 phase and activated differentiation. In addition, enzyme suppression by siSGPL1 upregulated keratin 1 and differentiation markers including involucrin and loricrin. When hyperproliferation of HEKn cells was induced by interleukin (IL)-17 and IL-22, pharmacologic inhibition of S1P lyase by SLI decreased proliferation and activated differentiation of HEKn cells simultaneously. In addition, SLI administration ameliorated imiquimod-induced psoriatic symptoms including erythema, scaling, and epidermal thickness in vivo. We thus demonstrated that S1P lyase inhibition reduces cell proliferation and induces keratinocyte differentiation, and that inhibition may attenuate psoriasiform changes. Collectively, these findings suggest that S1P lyase is a modulating factor for proliferation and differentiation, and support its potential as a therapeutic target for psoriasis in human keratinocytes.

Abstract Background Adiponectin exerts several beneficial cardiovascular effects, however their specific molecular mechanisms require additional understanding. This study investigated the mechanisms of adiponectin action in the heart during high fat diet (HFD) feeding or in palmitate (PA) treated H9c2 cardiomyoblasts. Methods 6-week-old male adiponectin knock out (Ad-KO) mice were fed chow or 60% HFD for 6 weeks then received saline or recombinant adiponectin (3μg/g body weight) for an additional 2 weeks. After acute insulin stimulation (4 U/kg), tissue and serum samples were collected for analysis. H9c2 cardiomyocytes were treated ±0.1 mM PA, the adiponectin receptor agonist AdipoRon, or the antioxidant MnTBAP then assays to analyze reactive oxygen species (ROS) production and cell death were conducted. To specifically determine the mechanistic role of S1P, gain and loss of function studies were conducted with adding S1P to cells or the inhibitors THI and SKI-II, respectively. Results HFD feeding induced cardiac insulin resistance in Ad-KO mice, which was reversed following replenishment of normal circulating adiponectin levels. In addition, myocardial total triglyceride was elevated by HFD and lipidomic analysis showed increased levels of ceramides and sphingosine-1-phosphate (S1P), with only the latter being corrected by adiponectin administration. Similarly, treatment of H9C2 cardiomyoblasts with PA led to a significant increase of intracellular S1P but not in conditioned media whereas AdipoRon significantly increased S1P production and secretion from cells. AdipoRon or the antioxidant MnTBAP significantly reduced PA-induced cell death. Gain and loss of function studies suggested S1P secretion and autocrine receptor activation mediated the effect of AdipoRon to attenuate PA-induced ROS production and cell death. Conclusion Our data establish adiponectin signaling-mediated increase in S1P secretion as a mechanism via which HFD or PA induced cardiomyocyte lipotoxicity, leading to insulin resistance and cell death, is attenuated.

A novel backstepping controller for uncertain single-input single-output pure-feedback nonaffine and nonautonomous nonlinear systems based on the time-derivative estimator (TDE) is proposed. Using TDEs, time-derivatives of error signals used in virtual control terms are directly estimated in every backstepping design steps. As a result, the control law has a relatively simple form. In addition, convergence of tracking error to a small neighborhood of origin is guaranteed regardless of unstructured uncertainties or unmatched disturbances in the controlled system. It does not require separate adaptive schemes or universal approximators such as neural networks or fuzzy logic systems adaptively tuned online to cope with system uncertainties. Simulation results demonstrated the simplicity and good performance of the proposed approximation-free controller.

Recently, because of the increase in the number of connections to Distributed Generation (DG), the problem of lowering voltage stability in the distribution system has become an issue. Reactive power compensators, such as Static Synchronous Compensators (STATCOM), may be used to solve the problem of voltage stability degradation. However, because of the complexity of the distribution system, it is very difficult to select the installation location for STATCOM. Furthermore, when installed in the wrong location, economical efficiency and availability problems may occur. This paper proposes a Virtual STATCOM Configuration and Control method that would operate like a single STATCOM based on multiple DGs connected to the system. The proposed Virtual STATCOM has the merit of being economical by using existing facilities without adding new power facilities, and it solves the problem of the difficulty of selecting the installation location because of the complexity of the distribution system. In addition, while the conventional STATCOM uses an independent control method in consideration of the power quality of the access point, the Virtual STATCOM performs the Point of Common Coupling (PCC) power quality compensation using the integrated control of multiple DGs connected to the system. In the proposed method, the Virtual STATCOM integrated control algorithm is configured by adopting linear programming, and the compensation is performed while considering the distance between DG and PCC, the inverter’s rated capacity, and the power generation. The performance of the Virtual STATCOM power quality compensation was verified using MATLAB/SIMULINK and Real Time Simulator (OPAL-RT).

The aim of the study was to elucidate the protective action of roasted Lycium chinense (rLF) enhanced kaempferol glycosides as bioactive components from obese-induced type 2 diabetes mice by investigating the histopathological, biochemical, and transcriptional analyses in blood, liver, and adipose tissue. The rLF extract significantly decreased the hypertrophy of fat deposition, pancreatic hyperplasia, hyperinsulinemia, hepatocellular steatosis, and nephropathy in a dose dependent manner (p

Abstract Background Dietary fructose can rapidly cause fatty liver in animals through de novo lipogenesis (DNL) and contribute to the development and severity of nonalcoholic fatty liver disease (NAFLD). In response to diverse cellular insults including endoplasmic reticulum (ER) and oxidative stress, phosphorylation of the eukaryotic translation initiation factor 2 alpha subunit (eIF2α) attenuates general translation initiation, allowing cells to conserve resources and initiate adaptive gene expression to restore homeostasis. The present study aimed to investigate the role of eIF2α phosphorylation in protecting against NAFLD induced by high fructose ingestion in a hepatocyte-specific eIF2α-phosphorylation-deficient mouse model. Methods Hepatocyte-specific non-phosphorylatable (S51A) eIF2α knock-in (A/A;fTg/0;Cre Hep /0, A/A Hep ) mice were generated by crossing A/A;fTg/fTg mice with the floxed WT eIF2α transgene (fTg) with Alfp-Cre recombinase transgenic S/A;Cre Hep /0 (S/A-Cre Hep ) mice. Hepatocyte-specific eIF2α-phosphorylation-deficient 3-month-old mice or 12-month-old mice were fed a 60% high fructose diet (HFrD) for 16 or 5 wks, and the effects of eIF2α-phosphorylation deficiency on NADP/NADPH and GSSG/GSH levels, ROS-defense gene expression, oxidative damage, cell death, and fibrosis were observed. Results Prolonged fructose feeding to mice caused dysregulation of the unfolded protein response (UPR) sensor activation and UPR gene expression, and then led to decreased expression of several ROS defense genes including glutathione biogenesis genes. Nonetheless, these changes were not sufficient to induce the death of eIF2α phosphorylation-sufficient hepatocytes. However, there was a substantial increase in hepatocyte death and liver fibrosis in fructose-fed middle-aged mice deficient in hepatocyte-specific eIF2α phosphorylation because of diminished antioxidant capacity due to reduced expression of antioxidant enzymes (GPX1 and HO-1) and lower NADPH and glutathione levels, as well as a possible increase in ROS-induced damage from infiltrating NOX2-expressing leukocytes; all this led to a vicious cycle of hepatocyte death and leukocyte infiltration. Conclusion Our findings suggest that eIF2α phosphorylation maintains NADPH and GSH levels and controls the expression of ROS-defense genes, thereby protecting hepatocytes from oxidative stresses induced by fructose metabolism.

A novel switching-differentiator (SD) that can asymptotically track the time derivative of time-varying signal was previously proposed. This paper extends the previous SD to estimation of higher-order time derivatives. This study shows that higher-order time-derivatives can be estimated by connecting multiple SDs in cascade form. By successive applying the generalized Barbalat’s lemma, all higher-order tracking errors also approach zeros asymptotically. To illustrate the performance of the proposed higher-order switching differentiator, simulations were performed for estimating higher-order time-derivatives of a signal.

The aim of the current study was to examine the preventive effect of green tea catechins on the transport of Benzo[a]pyrene (B[α]P) into the brain using an in vitro bio-mimic system coupled with sequential co-cultures. When 72 μM of catechins was pre-treated, cellular cytotoxicity induced by IC50 of B[α]P in human liver hepatocellular carcinoma (HepG2) and human brain microvascular endothelial cells (HBMECs) was reduced by 27% and 26%, respectively. The cellular integrity measured in HBMECs, which was exposed to IC50 of B[α]P, slowly decreased. However, the pre-treatment of catechins retained cellular integrity that was 1.14 times higher than with the absence of catechins. Co-consumption of catechins reduced not only the bio-accessibility of B[α]P in digestive fluid, but it also decreased absorption of B[α]P in human intestinal epithelial cells (Caco-2) with a HepG2 co-culture system. It was found that approximately a two times lower amount of B[α]P was transported via the blood-brain barrier (BBB) compared to only the B[α]P intake. These results are taken in conjunction with each other support that catechins could be able to prevent brain toxicity induced by B[α]P in the human body by limiting the bio-availability of B[α]P.

Graviola leaves contain much vitamin U (vit U), but their sensory quality is not good enough for them to be developed as food ingredients. Addition of excipient natural ingredients formulated alongside vit U as active ingredients could enhance not only its sensory quality but also its bioavailability. The objectives of this study were to measure the bioaccessibility and intestinal cellular uptake of bioactive components, including rutin, kaempferol-rutinoside, and vit U, from steamed extract of graviola leaves (SGV) and SGV enriched with kale extract (SGK), and to examine how much they can detoxify nicotine in HepG2 cells. The bioaccessibility of vit U from SGV and SGK was 82.40% and 68.03%, respectively. The cellular uptake of vit U in SGK by Caco-2 cells was higher than that in SGV. Cotinine content converted from nicotine in HepG2 cells for 120 min was 0.22 and 0.25 μg/mg protein in 50 μg/mL of SGV and SGK, respectively, which were 2.86 and 3.57 times higher than the no-treatment control. SGK treatment of HepG2 cells upregulated CYP2A6 three times as much as did that of SGV. Our results suggest that graviola leaf extract enriched with excipient ingredients such as kale could improve vit U absorption and provide a natural therapy for detoxifying nicotine.

Nonalcoholic fatty liver diseases (NAFLD) is characterized by accumulation of lipid droplets in the liver. The objective of this study was to evaluate protective effects of fermented Cordyceps militaris extract by Pediococcus pentosaceus ON188 (ONE) against hepatosteatosis and obesity in mice fed a high-fat diet (HFD). Eight-week-old male C57BL/6J mice were fed HFD mixed with ONE for four weeks and its effects on hepatosteatosis and obesity were examined. Although ONE did not change food intake, it reduced body weights of mice at administration dose of 200 mg/kg/day. Activities of lactate dehydrogenase (LDH), aspartate transaminase (AST), and alanine transaminase (ALT) as plasma parameters were reduced by ONE in a dose-dependent manner. Hepatic lipid droplets and triglyceride (TG) levels were also reduced by ONE due to upregulation of fatty acid oxidizing genes such as carnithine palmitoyltransferase (CPT1) and peroxisomal proliferator activated receptor α(PPARα) mediated by induction of sphingosine kinase 2 (SPHK2). In epididymal fat tissue, sizes of adipocytes were significantly reduced by ONE in a dose-dependent manner. This is mainly due to suppression of lipogenesis and upregulation of adipocyte browning genes. Collectively, these results suggest that fermented ONE can activate fatty acid oxidation via SPHK2 in the liver. It can also suppress lipogenesis and activate browning in adipose tissue. Thus, ONE might have potential to be used for the development of functional foods against liver dysfunction and obesity.

A novel differentiator-based approximation-free output-feedback controller for uncertain nonautonomous nonlinear pure-feedback systems is proposed. Using high-order sliding mode observer, which is a finite-time exact differentiator, the time-derivatives of the signal generated using tracking error and filtered input are directly estimated. As a result, the proposed non-backstepping control law and stability analysis are drastically simple. The tracking error vector is guaranteed to be exponentially stable in finite time regardless of the nonautonomous property in the considered system. It does not require neural networks or fuzzy logic systems, which are typically adopted to capture unstructured uncertainties intrinsic in the controlled system. As far as the authors know, there are no research results on the output-feedback controller for the uncertain nonautonomous pure-feedback nonlinear systems. The results of the simulation show clearly the performance and compactness of the control scheme proposed.

Cordyceps militaris is a medicinal mushroom used to treat immune-related diseases in East Asia. We investigated the anti-inflammatory effect of the extract of C. militaris grown on germinated Rhynchosia nulubilis (GRC) fermented with Pediococcus pentosaceus ON89A isolated from onion (GRC-ON89A) in vivo as well as in vitro. The anti-inflammatory effect of GRC-ON89A was investigated in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages. The total polyphenol content (TPC) and total flavonoid content (TFC) in the GRC-ON89A ethanol extract were significantly increased compared to that in GRC. GRC-ON89A hexane fraction (GRC-ON89A-Hex) inhibited the release of nitric oxide (NO) compared to that of the LPS-treated control without cytotoxicity in LPS-stimulated RAW 264.7 macrophages. GRC-ON89A-Hex decreased the inducible NO synthase (iNOS), cyclooxygenase 2 (COX2), and tumor necrosis factor (TNF)-α mRNA expression in LPS-stimulated RAW 264.7 macrophages. In addition, pre-treatment with GRC-ON89A-Hex significantly inhibited LPS-stimulated phosphorylation of mitogen-activated protein kinases (MAPKs) and nuclear factor (NF)-κB. To induce allergic contact dermatitis (ACD), 1-fluoro-2, 4-dinitrofluorobenzene (DNFB) was applied to the surface of the right ears of C57BL/6N mice. GRC-ON89A reduced the ear swelling and thickness in DNFB-induced ACD mice. This study demonstrates the potential usefulness of GRC-ON89A as an anti-inflammatory dietary supplement or drug.

The mechanism of FFA-induced insulin resistance is not fully understood. We have searched for effector molecules(s) in FFA-induced insulin resistance. Palmitic acid (PA) but not oleic acid (OA) induced insulin resistance in L6 myotubes through C-Jun N-terminal kinase (JNK) and insulin receptor substrate 1 (IRS-1) Ser307 phosphorylation. Inhibitors of ceramide synthesis did not block insulin resistance by PA. However, inhibition of the conversion of PA to lysophosphatidylcholine (LPC) by calcium-independent phospholipase A2 (iPLA2) inhibitors, such as bromoenol lactone (BEL) or palmitoyl trifluoromethyl ketone (PACOCF3), prevented insulin resistance by PA. iPLA2 inhibitors or iPLA2 small interfering RNA (siRNA) attenuated JNK or IRS-1 Ser307 phosphorylation by PA. PA treatment increased LPC content, which was reversed by iPLA2 inhibitors or iPLA2 siRNA. The intracellular DAG level was increased by iPLA2 inhibitors, despite ameliorated insulin resistance. Pertussis toxin (PTX), which inhibits LPC action through the G-protein coupled receptor (GPCR)/Gαi, reversed insulin resistance by PA. BEL administration ameliorated insulin resistance and diabetes in db/db mice. JNK and IRS-1Ser307 phosphorylation in the liver and muscle of db/db mice was attenuated by BEL. LPC content was increased in the liver and muscle of db/db mice, which was suppressed by BEL. These findings implicate LPC as an important lipid intermediate that links saturated fatty acids to insulin resistance.

Ceramide is among a number of potential lipotoxic molecules that are thought to modulate cellular energy metabolism. The heart is one of the tissues thought to become dysfunctional due to excess lipid accumulation. Dilated lipotoxic cardiomyopathy, thought to be the result of diabetes and severe obesity, has been modeled in several genetically altered mice, including animals with cardiac-specific overexpression of glycosylphosphatidylinositol (GPI)-anchored human lipoprotein lipase (LpLGPI). To test whether excess ceramide was implicated in cardiac lipotoxicity, de novo ceramide biosynthesis was inhibited pharmacologically by myriocin and genetically by heterozygous deletion of LCB1, a subunit of serine palmitoyltransferase (SPT). Inhibition of SPT, a rate-limiting enzyme in ceramide biosynthesis, reduced fatty acid and increased glucose oxidation in isolated perfused LpLGPI hearts, improved systolic function, and prolonged survival rates. Our results suggest a critical role for ceramide accumulation in the pathogenesis of lipotoxic cardiomyopathy.

Lipotoxic cardiomyopathy is caused by myocardial lipid accumulation and often occurs in patients with diabetes and obesity. This study investigated the effects of β-lapachone (β-lap), a natural compound that activates Sirt1 through elevation of the intracellular NAD+ level, on acyl CoA synthase (ACS) transgenic (Tg) mice, which have lipotoxic cardiomyopathy. Oral administration of β-lap to ACS Tg mice significantly attenuated heart failure and inhibited myocardial accumulation of triacylglycerol. Electron microscopy and measurement of mitochondrial complex II protein and mitochondrial DNA revealed that administration of β-lap restored mitochondrial integrity and biogenesis in ACS Tg hearts. Accordingly, β-lap administration significantly increased the expression of genes associated with mitochondrial biogenesis and fatty acid metabolism that were down-regulated in ACS Tg hearts. β-lap also restored the activities of Sirt1 and AMP-activated protein kinase (AMPK), the two key regulators of metabolism, which were suppressed in ACS Tg hearts. In H9C2 cells, β-lap-mediated elevation of AMPK activity was retarded when the level of Sirt1 was reduced by transfection of siRNA against Sirt1. Taken together, these results indicate that β-lap exerts cardioprotective effects against cardiac lipotoxicity through the activation of Sirt1 and AMPK. β-lap may be a novel therapeutic agent for the treatment of lipotoxic cardiomyopathy.

Bile acids concentration in liver is tightly regulated to prevent cell damage. Previous studies have demonstrated that deregulation of bile acid homeostasis can lead to cholestatic liver disease. Recently, we have shown that ER-bound transcription factor Crebh is a downstream effector of hepatic Cb1r signaling pathway. In this study, we have investigated the effect of alcohol exposure on hepatic bile acid homeostasis and elucidated the mediatory roles of Cb1r and Crebh in this process. We found that alcohol exposure or Cb1r-agonist 2-AG treatment increases hepatic bile acid synthesis and serum ALT, AST levels in vivo alongwith significant increase in Crebh gene expression and activation. Alcohol exposure activated Cb1r, Crebh, and perturbed bile acid homeostasis. Overexpression of Crebh increased the expression of key bile acid synthesis enzyme genes via direct binding of Crebh to their promoters, whereas Cb1r knockout and Crebh-knockdown mice were protected against alcohol-induced perturbation of bile acid homeostasis. Interestingly, insulin treatment protected against Cb1r-mediated Crebh-induced disruption of bile acid homeostasis. Furthermore, Crebh expression and activation was found to be markedly increased in insulin resistance conditions and Crebh knockdown in diabetic mice model (db/db) significantly reversed alcohol-induced disruption of bile acid homeostasis. Overall, our study demonstrates a novel regulatory mechanism of hepatic bile acid metabolism by alcohol via Cb1r-mediated activation of Crebh, and suggests that targeting Crebh can be of therapeutic potential in ameliorating alcohol-induced perturbation of bile acid homeostasis.