Targeting lipophagy as a potential therapeutic strategy for nonalcoholic fatty liver disease.

Nonalcoholic fatty liver disease (NAFLD) is becoming an increasingly serious disease worldwide. Unfortunately, no specific drug has been approved to treat NAFLD. Accumulating evidence suggests that lipotoxicity, which is induced by an excess of intracellular triacylglycerols (TAGs), is a potential mechanism underlying the ill-defined progression of NAFLD. Under physiological conditions, a balance is maintained between TAGs and free fatty acids (FFAs) in the liver. TAGs are catabolized to FFAs through neutral lipolysis and/or lipophagy, while FFAs can be anabolized to TAGs through an esterification reaction. However, in the livers of patients with NAFLD, lipophagy appears to fail. Reversing this abnormal state through several lipophagic molecules (mTORC1, AMPK, PLIN, etc.) facilitates NAFLD amelioration; therefore, restoring failed lipophagy may be a highly efficient therapeutic strategy for NAFLD. Here, we outline the lipophagy phases with the relevant important proteins and discuss the roles of lipophagy in the progression of NAFLD. Additionally, the potential candidate drugs with therapeutic value targeting these proteins are discussed to show novel strategies for future treatment of NAFLD.

Triglyceride-lowering and anti-inflammatory mechanisms of omega-3 polyunsaturated fatty acids for atherosclerotic cardiovascular risk reduction.

Atherosclerotic cardiovascular disease (ASCVD) is the leading cause of death globally. Omega-3 polyunsaturated fatty acids (PUFAs) including eicosapentaenoic acid and docosahexaenoic acid have been extensively studied as both dietary supplement and pharmaceutical agent for the prevention of ASCVD. Epidemiological and retrospective studies have long shown the inverse relationship of omega-3 PUFA consumption and ASCVD event but results of previous large randomized controlled trials have not consistently shown the same effect. Meta-analysis and a recent clinical trial using a high dose of eicosapentaenoic acid showed convincing protective effects of omega-3 PUFAs on ASCVD. Emerging evidence shows that both chronic inflammation and hypertriglyceridemia increase the risk of atherosclerosis. Amelioration of the inflammatory process and reduction of hypertriglyceridemia provide two mechanisms on the prevention and management of ASCVD, and agents with both of these effects are more potent and desirable. Omega-3 PUFAs exert anti-hypertriglyceridemia effect, ameliorate inflammation, and maintain the resolution of inflammation homeostasis pleiotropically through multiple molecular and cellular mechanisms. This review presents the pathophysiology of atherosclerosis, the mechanisms of omega-3 PUFAs on the reduction of the atherosclerotic risk, and the current clinical utilities of omega-3 PUFAs on the prevention of ASCVD.

Phenolic compounds from the leaves of Crataegus pinnatifida Bge. var. major N.E.Br. And their lipid-lowering effects.

A phytochemical study on the leaves of Crataegus pinnatifida Bge. var. major N.E.Br. was carried out, which finally led to the isolation of nineteen phenolic compounds (1-19). The structures of all compounds were established mainly by NMR and MS spectroscopic analysis as well as the necessary ECD experimental evidence, of which compounds 1-4 (crataegunins A-D) were identified as new phenylpropanoid-substituted epicatechins. HepG2 cells were induced by oleic acid and palmitic acid to establish the model of lipid metabolism disorder. All isolated compounds were used to intervene in the model, and the contents of triglyceride (TG) and total cholesterol (TC) were detected. Compound 2 could significantly reduce the content of TG, while compounds 2 and 11 both have good activity in reducing TC content.

Anti-hyperlipidemic potential of natural product based labdane-pyrroles via inhibition of cholesterol and triglycerides synthesis.

Hyperlipidemia is the clinical condition where blood has an increased level of lipids, such as cholesterol and triglycerides. Therefore controlling hyperlipidemia is considered to be a protective strategy to treat many associated diseases. Thus, a novel natural product derived pyrrole, and pyrazole-(E)-Labda-8(17),12-diene-15,16-dial conjugates with cholesterol and triglycerides synthesis inhibition potential was designed through scaffold hopping approach and synthesized via one-pot selective cycloaddition. Amongst the tested hybrids, 3i exhibited excellent activity against triglyceride and cholesterol synthesis with the percentage inhibition of 71.73 ± 0.78 and 68.61 ± 1.19, which is comparable to the positive controls fenofibrate and atorvastatin, respectively. Compounds 3j and 3k also exhibited the considerable potential of promising leads. The HMG CoA reductase inhibitory activity of the compounds was consistent with that of inhibitory activity of cholesterol synthesis. Compound 3i showed the highest inhibitory potential (78.61 ± 2.80) percentage of suppression, which was comparable to that of the positive control pravastatin (78.05 ± 5.4). Favourably, none of the compounds showed cytotoxicity (HepG2) in the concentration ranging from 0.5 to 100 µM.

Assessment of exopolysaccharides, bacteriocins and in vitro and in vivo hypocholesterolemic potential of some Egyptian Lactobacillus spp.

Lactobacilli probiotics have been suggested to reduce cholesterol with low side effects to host. Bacteriocins and exopolysaccharides (EPSs) production are two meaningful examples of functional applications of lactobacilli in the food industry. Eight Lactobacillus strains were isolated from some Egyptian fermented food and tested for their probiotic properties. Analysis of the monosaccharide composition by thin layer chromatography showed the presence of glucose, galactose and unknown sugar. The main functional groups of EPSs were elucidated by Fourier-Transform Infrared Spectroscopy. Their fermentation cultures displayed powerful antioxidant activities extending from 97.5 to 99%, 40-75% for their EPSs and free cells, respectively, and exhibited in vitro cholesterol downgrading from 48 to 82% and 72 to 91% after 48 and 120 h, respectively. Their EPSs showed good anticancer activities against carcinoma cells with low IC50 values for HCT-116, PC-3 and HepG-2 cells. To the best of our knowledge, there have been no previous reports on the potential of Lactobacillus EPSs activity against PC-3. The selected strains, L. plantarum KU985433 and L. rhamnosus KU985436 produced two different bacteriocins as detected by gel permeation chromatography with good antimicrobial activities. In vivo study demonstrated that feeding Westar rats with fermented milk exhibited greater cholesterol, LDL and blood triglyceride reduction for both strains. Whereas, HDL was increased by about 43 and 38%, respectively, and the atherogenic indices decreased.

TMT-based proteomics analysis reveals the efficacy of jiangzhuo formula in improving the lipid profiles of dyslipidemia rats.

ETHNOPHARMACOLOGICAL RELEVANCE: Jiangzhuo Formula (JZF) is a traditional Chinese herbal prescription that is clinically applied to treat dyslipidemia. However, the mechanism underlying its efficacy remains unexplored. AIM OF THE STUDY: This study aims to elucidate the underlying mechanisms, explore potential pathways, and identify the key proteins of JZF for the treatment of dyslipidemia. METHODS: In this work, Q-Orbitrap high-resolution liquid chromatography mass spectrometry was used to identify the natural ingredients in JZF, rats with dyslipidemia were established via a high-fat diet for four weeks, then the dyslipidemia rats were treated with high-dose JZF (9 g/d) and low-dose JZF (4.5 g/d) for four weeks. After treatment, serum lipid detection and Oil-red-O staining were conducted to assess the efficacy of JZF in ameliorating dyslipidemia. Tandem mass tag (TMT) -based quantitative proteomics technology was then used to evaluate the roles and importance of proteins from the extracted hepatic tissue. The differentially expressed proteins were assessed by Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways, Gene Ontology (GO), and protein-protein interaction (PPI) networks. Western blot and PCR analysis were used to validate the potential targets regulated by JZF. RESULTS: JZF could significantly improve the blood lipid profiles of serum and fat deposits of the liver. A total of 123 differentially expressed proteins were detected after JZF intervention, comprising 65 up-regulated proteins and 58 down-regulated proteins. The KEGG pathway analysis revealed that cholesterol metabolism, the PPAR signaling pathway, and bile secretion were the principal pathways involved in the disordered lipid metabolism, while GO analysis suggested that proteins that are located in the cell, regulate cellular processes, and show binding activity contribute to reductions in lipids. The combination of proteomics, Western blot, and PCR suggested that Apolipoprotein B (APOB), Apolipoprotein E (APOE), cholesterol 7 alpha-hydroxylase A1 (CYP7A1), and Hydroxymethylglutaryl-CoA synthase 1 (HMGCS1) might play critical roles in JZF's lipid-lowering network. CONCLUSION: JZF can effectively improve lipid profiles via multiple pathways involved in cholesterol metabolism, the PPAR signaling pathway, and bile secretion. Generally, the proteomics techniques used in this research show that JZF could be a promising drug for the treatment of dyslipidemia.

Tri-Herbal Medicine Divya Sarva-Kalp-Kwath (Livogrit) Regulates Fatty Acid-Induced Steatosis in Human HepG2 Cells through Inhibition of Intracellular Triglycerides and Extracellular Glycerol Levels.

Steatosis is characterized by excessive triglycerides accumulation in liver cells. Recently, application of herbal formulations has gained importance in treating complex diseases. Therefore, this study explores the efficacy of tri-herbal medicine Divya Sarva-Kalp-Kwath (SKK; brand name, Livogrit) in treating free fatty acid (FFA)-induced steatosis in human liver (HepG2) cells and rat primary hepatocytes. Previously, we demonstrated that cytosafe SKK ameliorated CCl4-induced hepatotoxicity. In this study, we evaluated the role of SKK in reducing FFA-induced cell-death, and steatosis in HepG2 through analysis of cell viability, intracellular lipid and triglyceride accumulation, extracellular free glycerol levels, and mRNA expression changes. Plant metabolic components fingerprinting in SKK was performed via High Performance Thin Layer Chromatography (HPTLC). Treatment with SKK significantly reduced the loss of cell viability induced by 2 mM-FFA in a dose-dependent manner. SKK also reduced intracellular lipid, triglyceride accumulation, secreted AST levels, and increased extracellular free glycerol presence in the FFA-exposed cells. SKK normalized the FFA-stimulated overexpression of SREBP1c, FAS, C/EBPα, and CPT1A genes associated with the induction of steatosis. In addition, treatment of rat primary hepatocytes with FFA and SKK concurrently, reduced intracellular lipid accumulation. Thus, SKK showed efficacy in reducing intracellular triglyceride accumulation and increasing extracellular glycerol release, along with downregulation of related key genetic factors for FFA-associated steatosis.

Treatment with Volanesorsen, a 2'-O-Methoxyethyl-Modified Antisense Oligonucleotide Targeting APOC3 mRNA, Does Not Affect the QTc Interval in Healthy Volunteers.

The aim of this study was to assess the effect of volanesorsen on the corrected QT (QTc) interval. This thorough QT study enrolled 52 healthy male and female subjects who were randomized at a single site in a four-way crossover study. Subjects were randomly assigned to 1 of 12 treatment sequences and crossed over into four treatment periods over the course of which each subject was to receive a single therapeutic dose of volanesorsen as a 300 mg subcutaneous (SC) injection, a single supratherapeutic dose of volanesorsen as 300 mg intravenous (IV) infusion, a single oral (PO) dose of moxifloxacin (positive control), and placebo dose. The study demonstrated that volanesorsen 300 mg SC and 300 mg IV did not have a clinically relevant effect on ΔΔQTcF exceeding 10 ms. The largest mean effect at any postdose time point was 3.0 ms (90% confidence interval [CI]: 0.8-5.2) after SC dosing and 1.8 ms (90% CI -0.4 to 4.0) after IV dosing. Volanesorsen, at the studied therapeutic and supratherapeutic doses, does not have a clinically meaningful effect on the QTc.

Metabolic effects of PCSK9 inhibition with Evolocumab in subjects with elevated Lp(a).

BACKGROUND: Epidemiological studies substantiated that subjects with elevated lipoprotein(a) [Lp(a)] have a markedly increased cardiovascular risk. Inhibition of proprotein convertase subtilisin/kexin type 9 (PCSK9) lowers both LDL cholesterol (LDL-C) as well as Lp(a), albeit modestly. Effects of PCSK9 inhibition on circulating metabolites such as lipoprotein subclasses, amino acids and fatty acids remain to be characterized. METHODS: We performed nuclear magnetic resonance (NMR) metabolomics on plasma samples derived from 30 individuals with elevated Lp(a) (> 150 mg/dL). The 30 participants were randomly assigned into two groups, placebo (N = 14) and evolocumab (N = 16). We assessed the effect of 16 weeks of evolocumab 420 mg Q4W treatment on circulating metabolites by running lognormal regression analyses, and compared this to placebo. Subsequently, we assessed the interrelationship between Lp(a) and 14 lipoprotein subclasses in response to treatment with evolocumab, by running multilevel multivariate regression analyses. RESULTS: On average, evolocumab treatment for 16 weeks resulted in a 17% (95% credible interval: 8 to 26%, P < 0.001) reduction of circulating Lp(a), coupled with substantial reduction of VLDL, IDL and LDL particles as well as their lipid contents. Interestingly, increasing concentrations of baseline Lp(a) were associated with larger reduction in triglyceride-rich VLDL particles after evolocumab treatment. CONCLUSIONS: Inhibition of PCSK9 with evolocumab markedly reduced VLDL particle concentrations in addition to lowering LDL-C. The extent of reduction in VLDL particles depended on the baseline level of Lp(a). Our findings suggest a marked effect of evolocumab on VLDL metabolism in subjects with elevated Lp(a). TRIAL REGISTRATION: Clinical trial registration information is registered at ClinicalTrials.gov on April 14, 2016 with the registration number NCT02729025.

The next generation of triglyceride-lowering drugs: will reducing apolipoprotein C-III or angiopoietin like protein 3 reduce cardiovascular disease?

PURPOSE OF REVIEW: Apolipoprotein C-III (ApoC-III) and angiopoietin like protein 3 (angptl3) have emerged as key regulators of triglyceride metabolism. Based on Mendelian randomisation studies, novel therapeutic strategies inhibiting these proteins using monoclonal antibodies or gene silencing techniques might reduce residual cardiovascular disease (CVD) risk in dyslipidemic patients. This article aims to review the role of apoC-III and angptl3 in triglyceride metabolism and combine early clinical evidence of CVD reducing potential of these new therapeutic targets. RECENT FINDINGS: Angptl3 inhibition by mAb or antisense therapy has recently completed phase I and II studies, respectively and demonstrate robust apolipoprotein B (apoB) lowering up to 46%. Volanesorsen is an antisense therapy approved for patients with extremely elevated plasma triglyceride levels in which it showed no consistent apoB reduction. However, the GalNAc-conjugated oligonucleotide showed moderate (up to ∼30%) apoB reduction in a phase 1/2a dose-finding study. SUMMARY: Angptl3 and apoC-III are novel targets in lipoprotein metabolism that reduce triglycerides when inhibited. The expected CVD risk reduction may be mediated through reduced triglyceride-rich lipoprotein particle number, reflected by apoB, rather than triglyceride reduction per se. Limited human evidence shows that apoC-III and angptl3 inhibition both potently lower triglycerides, but since angptl3 inhibition reduces apoB more robustly it may be expected to confer more favorable CVD risk reduction.

Long-term statin persistence is poor among high-risk patients with dyslipidemia: a real-world administrative claims analysis.

BACKGROUND: A decade ago, statin persistence was < 50% after 1 year, and recent short-term analyses have revealed very little progress in improving statin persistence, even in patients with a prior cardiovascular (CV) event. Data on longer-term statin persistence are lacking. We measured long-term statin persistence in patients with high CV risk. METHODS: This retrospective administrative claims analysis of the Optum Research Database included patients aged ≥ 45 years with diabetes and/or atherosclerotic CV disease (ASCVD) who had a statin prescription filled in 2010. It included an elevated triglycerides (TG) cohort of patients with index date in 2010 and TG ≥ 150 mg/dL (n = 23,181) and a propensity-matched comparator cohort with TG < 150 mg/dL and high-density lipoprotein cholesterol > 40 mg/dL (n = 23,181). Both cohorts were followed for ≥ 6 months up to March 2016. RESULTS: The probability of remaining on a prescription fill for index statin therapy was 47% after 1 year and 19% after 5 years in both cohorts. Statin persistence was worse among women than men, and among younger versus older patients (P < 0.001 for all comparisons). After 5 years, the probability of remaining on a prescription fill for index statin was < 25% across all subgroups assessed including patients with and without baseline revascularization, heart failure, peripheral artery disease and renal disease. Similar results were observed in a subcohort analysis of patients with TG 200-499 mg/dL. CONCLUSIONS: Long-term statin persistence after 5 years is alarmingly low (< 25%) and is a public health concern.

Anti-Diabetic Effect of a Shihunine-Rich Extract of Dendrobium loddigesii on 3T3-L1 Cells and db/db Mice by Up-Regulating AMPK-GLUT4-PPARα.

The stems of Dendrobium loddigesii, a Chinese herb, are often used to treat diabetes and its polar extract is rich in shihunine, a water-soluble Orchidaceae alkaloid, but little is known about the anti-diabetes effects and mechanism of shihunine. This study investigated the anti-diabetic effect of a shihunine-rich extract of D. loddigesii (DLS) based on 3T3-L1 cells and db/db mice. The underlying mechanisms were primarily explored using Western blot analysis and immunohistochemical staining. The 3T3-L1 cell experiments showed that DLS can reduce the intracellular accumulation of oil droplets as well as triglycerides (p < 0.001) and promote the 2-[N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)amino]-2deoxyglucose (2-NBDG) uptake of 3T3-L1 cells (p < 0.001). The animal experiments confirmed that after 8 weeks of DLS treatment, the body weight, fasting blood sugar, and serum lipid levels of mice were significantly lowered, and the oral glucose tolerance test and serum insulin level were significantly improved compared to the no-treatment diabetes mellitus group. Further histomorphology observation led to the conclusion that the quantities of islet cells were significantly increased and the increase in adipose cell size was significantly suppressed. The immunohistochemical test of pancreatic tissue revealed that DLS inhibited the expression of cleaved cysteine aspartic acid-specific protease 3 (cleaved caspase-3). Western blot experiments showed that DLS had agonistic effects on adenosine monophosphate (AMP)-activated protein kinase phosphorylation (p-AMPK) and increased the expression levels of peroxisome proliferator-activated receptor α (PPARα) and glucose transporter 4 (GLUT4) in liver or adipose tissues. These data suggest that the shihunine-rich extract of D. loddigesii is an anti-diabetic fraction of D. loddigesii. Under our experimental condition, DLS at a dose of 50 mg/kg has good anti-diabetic efficacy.

Anti-proteinuria effect of antibody against ANGPTL3 coil-coiled domain on adriamycin-induced nephropathy in mice.

Proteinuria is an important marker and is closely related to the progressive decline of renal function. Our previous research showed that angiopoietin-like-3 (ANGPTL3) plays a crucial role in proteinuria. In this study, we prepared an antibody against ANGPTL3 coil-coiled domain (ANGPTL3-CCD) and investigated the protective effect of anti-ANGPTL3-CCD antibody in mice with adriamycin-induced nephropathy. Nephropathy was established by adriamycin injection at a dose of 25 mg per kg in 8-12 week-old male mice in the ADR group. Blockade of ANGPTL3 by anti-ANGPTL3-CCD antibody (20 mg per kg) was performed every three days nine times after adriamycin injection in the ADR plus anti-angptl3-antibody group. The anti-ANGPTL3-CCD antibody can specifically recognize ANGPTL3. After anti-ANGPTL3-CCD antibody intervention, the urinary protein level in the ADR plus anti-angptl3-antibody group was significantly lower than that in the ADR group. Serum albumin was higher and triglyceride and total cholesterol were lower in the ADR plus anti-angptl3-antibody group than in the ADR group. The levels of serum creatinine did not significantly differ among the groups. Focal sclerotic glomeruli and podocyte foot processes extensive fusion were found in the renal tissue of the ADR group, whereas no sclerotic glomeruli and only partial fusion were found in the ADR plus anti-angptl3-antibody group. This study demonstrated that the anti-ANGPTL3-CCD antibody ameliorated proteinuria and podocyte dysfunction in adriamycin-induced nephropathy in mice.

A Randomized Controlled Trial of a Herbal Compound for Improving Metabolic Parameters in Diabetic Patients with Uncontrolled Dyslipidemia.

OBJECTIVE: The aim of this randomized controlled trial was to investigate the effects of a polyherbal compound consisting of Aloe vera, black seed, fenugreek, garlic, milk thistle, and psyllium on diabetic patients with uncontrolled dyslipidemia. METHODS: Fifty patients with type 2 diabetes who had dyslipidemia in spite of statin therapy were randomly allocated to two groups: control group (n = 25) receiving a conventional therapy with hypolipidemic and hypoglycemic drugs and intervention group (n = 25) receiving both the conventional therapy and the herbal compound (one sachet twice daily) for 12 weeks. Each sachet contained 300 mg of Aloe vera leaf gel, 1.8 g of black seed, 300 mg of garlic, 2.5 g of fenugreek seed, 1 g of psyllium seed, and 500 mg of milk thistle seed. RESULTS: The levels of serum triglyceride, total cholesterol, low-density lipoprotein, and HbA1c showed a significant in-group improvement in the intervention group. However, the effects of the herbal compound on fasting blood glucose remained insignificant. The compound had no unwanted effect on the kidney function parameters (urea, creatinine) and serum liver enzymes (alanine aminotransferase and aspartate transaminase). CONCLUSION: The tested herbal compound, as an add-on to statin therapy, was effective in lowering the serum lipids in diabetic patients with uncontrolled dyslipidemia.

Real-world use of PCSK9 inhibitors: A single-center experience.

OBJECTIVE: Hyperlipidemia is an important risk factor for atherosclerotic cardiovascular disease. Many patients are intolerant to or have limited benefit from statins. Proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors have been approved for treating hyperlipidemia in these patients. We sought to investigate the impact of these medications in a real-world cardiology practice. METHODS: This was a retrospective study of 17 patients with either heterozygous familial hypercholesterolemia or established atherosclerotic cardiovascular disease with low-density lipoprotein cholesterol (LDL-C) levels above the treatment target despite maximally tolerated statins. Baseline lipid profile was compared with a repeat lipid profile obtained 4 to 6 weeks after initiating treatment with a PCSK9 inhibitor. RESULTS: The average duration of PCSK9 inhibitor treatment was 10.7 months. Lipid profile comparison showed that total cholesterol decreased from 243 ± 72 to 148 ± 39 (mg/dL) (39% reduction), triglycerides decreased from 185 ± 86 to 149 ± 62 (mg/dL) (19.5% reduction), high-density lipoprotein cholesterol increased from 56 ± 20 to 62 ± 26 (mg/dL) (10.7% increase), and LDL-C decreased from 154 ± 30 to 57 ± 32 (mg/dL) (63% reduction) from baseline. CONCLUSIONS: PCSK9 inhibitors as add-on therapy to maximally tolerated statins resulted in an approximately 63% reduction in LDL-C.

Tackling Residual Atherosclerotic Risk in Statin-Treated Adults: Focus on Emerging Drugs.

Epidemiological studies and meta-analyses have consistently suggested the importance of lowering low-density lipoprotein cholesterol (LDL-C) to reduce cardiovascular (CV) events. However, these studies and mechanistic studies using intracoronary imaging modalities have reported patients who continue to experience CV events or disease progression despite optimal LDL-C levels on statins. These findings, including statin intolerance, have highlighted the importance of exploring additional potential therapeutic targets to reduce CV risk. Genomic insights have presented a number of additional novel targets in lipid metabolism. In particular, proprotein convertase subtilisin/kexin type 9 inhibitors have rapidly developed and recently demonstrated their beneficial impact on CV outcomes. Triglyceride (TG)-rich lipoproteins have been recently reported as a causal factor of atherosclerotic cardiovascular disease (ASCVD). Indeed, several promising TG-targeting therapies are being tested at various clinical stages. In this review, we present the evidence to support targeting atherogenic lipoproteins to target residual ASCVD risk in statin-treated patients.

Influence of Resveratrol on Sphingolipid Metabolism in Hepatocellular Carcinoma Cells in Lipid Overload State.

BACKGROUND: Obesity is characterized by increased long chain fatty acids (LCFA) uptake and impaired lipid metabolism in hepatocytes. Consequently, an enhanced intracellular lipid content, including sphingolipids, may lead to lipotoxicity. It is believed that resveratrol (RSV), one of the most extensively studied plant-derived polyphenols, and its interaction with sphingolipid metabolism may constitute one of the major therapeutic targets for cancer and metabolic diseases treatment. OBJECTIVE: The aim of this study was to ascertain, whether resveratrol may affect sphingolipid metabolic pathways, enzymes and transporters in a lipid overload state. METHODS: The experiments were conducted on hepatocellular carcinoma cells (HepG2) incubated with RSV and/or Palmitic Acid (PA) at the concentration of 0.5 mM and 50 µM, respectively for 16h. Intra- and extracellular sphingolipid concentrations were assessed by high-performance liquid chromatography and gas liquid chromatography. Moreover, the expression of caspase 3, selected fatty acid transporters and sphingolipid metabolism pathway proteins were estimated by Western Blot. RESULTS: RSV alone and together with PA significantly increased the intracellular concentration of ceramide, sphinganine and sphingosine as well as the expression of enzymes related to de novo ceramide synthesis pathway. Moreover, in our study, we observed augmented ceramide and sphingomyelin efflux into the incubation media in these groups. In addition, RSV substantially reduced intracellular triacylglycerols accumulation in lipid overload conditions. CONCLUSION: The above-mentioned findings suggest that RSV, at least partially, demonstrates a potential protective effect on HepG2 cells in a lipid overload state.

Dipeptidyl peptidase-4 inhibition protects the liver of insulin-resistant female rats against triglyceride accumulation by suppressing uric acid.

Dipeptidyl peptidase-4 (DPP-4) inhibition has been shown to exert beneficial effects against insulin resistance (IR) and type 2 diabetes. Combined oral contraceptive (COC) treatment is associated with impaired glucose and lipid metabolism but the mechanisms are elusive. We therefore, hypothesized that DPP-4 inhibition ameliorates COC-induced glucose dysregulation and hepatic triglyceride (TG) accumulation through adenosine deaminase (ADA) /xanthine oxidase (XO) /uric acid-dependent pathway. Female Wistar rats received (po) vehicle and COC (1.0 µg ethinylestradiol plus 5.0 µg levonorgestrel; po) with or without DPP-4 inhibitor (sitagliptin; 100 mg/kg; po) for 8 weeks (n = 6/group). Glucose dysmetabolism was assessed by elevated fasting blood glucose, impaired oral glucose tolerance test and homeostatic model assessment of IR. Treatment with COC led to increased plasma fasting glucose, triglyceride-glucose index, 1-h postload glucose response, insulin, free fatty acid, IR and impaired glucose tolerance. COC treatment also resulted in increased plasma and hepatic TG, TG/HDL-cholesterol ratio, malondialdehyde, uric acid (plasma; 25.2 ± 0.6 mg/dl; hepatic 128.9 ± 8.0 mg/100 mg tissue), lactate dehydrogenase, DPP-4, ADA and XO (plasma;10.5 ± 1.1 U/L; hepatic 21.2 ± 1.4 U/g protein) activities. Likewise, COC led to reduction in nitric oxide level. However, DPP-4 inhibition significantly ameliorated these alterations induced by COC treatment through suppression of uric acid (plasma; 15.1 ± 1.0 mg/dl, hepatic; 75.6 ± 5.0 mg/100 mg tissue), XO (plasma; 4.1 ± 0.9 U/L, hepatic; 8.7 ± 0.4 U/g protein), ADA and DPP-4 activities suggesting their involvement in glucose dysregulation and hepatic TG accumulation induced by COC treatment. Therefore, DPP-4 inhibition would impact positively on cardiometabolic disorders, at least in part, through XO, ADA and uric acid suppression.

Preparation and Characterization of Resveratrol Loaded Pectin/Alginate Blend Gastro-Resistant Microparticles.

BACKGROUND: The use of resveratrol as a dietary supplement is limited because it is easily oxidized and, after oral ingestion, it is metabolized into enterocytes and hepatocytes. Thus, new formulations are needed in order to improve its oral bioavailability. OBJECTIVE: The objective of this study was to develop and characterize a gastro-resistant formulation of resveratrol for oral administration as a dietary supplement. METHOD: Resveratrol was encapsulated in Eudragit-coated pectin-alginate microparticles. RESULTS: The microparticle size was about 1450 µm, with an encapsulation efficiency of 41.72% ± 1.92%. The dissolution assay conducted, as specified in the European Pharmacopoeia for delayed-release dosage forms, revealed that our microparticles were gastro-resistant, because the resveratrol percentage released from microparticles in acid medium was less than 10%. In addition, the high-performance liquid chromatographic (HPLC) method developed for resveratrol content quantification in the microparticles was validated according to International Council for Harmonisation (ICH) Q2 (R1) guidelines. Finally, the biological activity of resveratrol was investigated in 3T3-L1 mature adipocytes, concluding that the encapsulation process does not affect the activity of resveratrol. CONCLUSION: In summary, the gastro-resistant microparticles developed could represent a suitable method of including resveratrol in dietary supplements and in functional foods used in obesity therapy.