Lipid Accumulation in HepG2 Cells Is Attenuated by Strawberry Extract through AMPK Activation

Toxicity and Hepatoprotective Effects of ZnO Nanoparticles on Normal and High-Fat Diet-Fed Rat Livers: Mechanism of Action

This experiment aimed to evaluate the beneficial and toxic properties of synthetic zinc oxide nanoparticles (ZnO NPs) on the liver of normal and high-fat diet (HFD) fed-rats. The ZnO NPs were synthesized and, its characterizations were determined by different techniques. Effect of ZnO NP on cell viability, liver enzymes and lipid accumulation were measured in HepG2 cells after 24 h. After that, rats orally received various dosages of ZnO NPs for period of 4 weeks. Toxicity tests were done to determine the appropriate dose. In the subsequent step, the hepatoprotective effects of 5 mg/kg ZnO NPs were determined in HFD-fed rats (experiment 2). The oxidative stress, NLRP3 inflammasome, inflammatory, and apoptosis pathways were measured. Additionally, the activity of caspase 3, nitric oxide levels, antioxidant capacity, and various biochemical factors were measured. Morphological changes in the rat livers were also evaluated by hematoxylin and eosin (H & E) and Masson trichrome. Liver apoptosis rate was also approved by terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) assay. Treatment of animals with 5 mg/ZnO NPs revealed potential hepatoprotective properties, while ZnO NPs at the doses of above 10 mg/kg showed toxic effects. Antioxidant enzyme gene expression and activity were significantly augmented, while apoptosis, NLRP3 inflammasome, and inflammation pathways were significantly reduced by 5 mg/kg ZnO NPs. Liver histopathological alterations were restored by 5 mg/kg ZnO NPs in HFD. Our study highlights the hepatoprotective effects of ZnO NPs against the HFD-induced liver damage, involving antioxidant, anti-inflammatory, and anti-apoptotic pathways, indicating their promising therapeutic potential.

Growth parameters, phytochemicals, and antitumor activity of wild and cultivated ice plants (Mesembryanthemum crystallinum L.)

The ice plant (Mesembryanthemum crystallinum L.) is a halophyte that could become an alternative crop because of its interest as a functional food and its adaptation to high-saline soils. In this work, leaves from wild ice plants were compared with their cultivated counterparts in a soilless system at different salinities and light exposures for assessing growth parameters, moisture, fatty acid profiles, total carotenoids, phenolic compounds, vitamin C, antioxidant activity, and antiproliferative activity against the HT-29 colorectal cancer cell line. Moisture ranged between 876 and 955 g kg-1, and wild plants contained higher proportions of α-linolenic acid (58.7%-60.7% of total fatty acids) than cultivated ones (20.4%-36.6%). Vitamin C ranged between 819 and 1143 mg kg-1 fresh leaves. Higher salinity led to a larger production of carotenoids, whereas plant mass, total phenolic content, and antioxidant activity increased in plants grown using L8 NS1 and L8 AP67 lamps in comparison with white-light ones. Phenolic profiles were assessed by LC coupled to a hybrid mass spectrometer Q-Orbitrap. Total phenolic acid content was 3-4-fold higher than that of flavonoids, and sinapic, p-coumaric, gallic, 4-hydroxybenzoic, and 2-hydroxy-4-methoxybenzoic acids, as well as gallocatechin, occurred in all samples. Hydroalcoholic extracts of ice plant leaves showed dose- and time-dependent antiproliferative activity against the HT-29 human colorectal cancer cell line, and GI50 was between 920 and 977 μg mL-1 of plant extract. This work contributes to improving knowledge about the growth parameters, phytochemical profiles, and biological activities of wild and cultivated ice plants.

Cyanidin-3-O-glucoside ameliorates hydrogen peroxide-induced oxidative stress by regulating HMGCR-mediated cholesterol anabolism in HEK-293T cells

Cyanidin-3-O-glucoside (C3G), as a typical anthocyanin, exhibits excellent antioxidant effects. This study aimed to demonstrate the role and mechanism of C3G in regulating 3-hydroxy-3-methylglutaryl-coenzyme A reductase (HMGCR)-mediated cholesterol anabolism on H2O2-induced oxidative stress in HEK-293T cells. Firstly, the inhibitory effect of C3G on oxidative stress was confirmed by CCK-8, ROS, and mitochondrial membrane potential (MMP) experiments. Then, proteomics was used to investigate and screen differentially expressed proteins in inhibiting cellular oxidative stress by C3G. HMGCR was screened as a key differentially expressed protein by proteomic analysis. The results verified that C3G could reduce cholesterol levels by inhibiting sterol regulatory element-binding protein (SREBP2)/HMGCR pathway, increasing ATP, and reducing acetyl-CoA. Finally, HMGCR had been shown to positively increase ROS accumulation and decrease MMP, which were reversed by intervention of C3G through a series of knockdown and overexpression experiments. In conclusion, the results demonstrated that C3G could inhibit the disorder of cholesterol synthesis in oxidative stress cells by regulating the ROS/SREBP2/HMGCR pathway.

Ferulic acid restores mitochondrial dynamics and autophagy via AMPK signaling pathway in a palmitate-induced hepatocyte model of metabolic syndrome

Mitochondrial dysfunction, characterized by elevated oxidative stress, impaired energy balance, and dysregulated mitochondrial dynamics, is a hallmark of metabolic syndrome (MetS) and its comorbidities. Ferulic acid (FA), a principal phenolic compound found in whole grains, has demonstrated potential in ameliorating oxidative stress and preserving energy homeostasis. However, the influence of FA on mitochondrial health within the context of MetS remains unexplored. Moreover, the impact of FA on autophagy, which is essential for maintaining energy homeostasis and mitochondrial integrity, is not fully understood. Here, we aimed to study the mechanisms of action of FA in regulating mitochondrial health and autophagy using palmitate-treated HepG2 hepatocytes as a MetS cell model. We found that FA improved mitochondrial health by restoring redox balance and optimizing mitochondrial dynamics, including biogenesis and the fusion/fission ratio. Additionally, FA was shown to recover autophagy and activate AMPK-related cell signaling. Our results provide new insights into the therapeutic potential of FA as a mitochondria-targeting agent for the prevention and treatment of MetS.

Antiadipogenic Effect of Citrus Flavonoids: Evidence from RNA Sequencing Analysis and Activation of AMPK in 3T3-L1 Adipocytes

Citrus fruits are rich in dietary flavonoids and have many health benefits, but their antiadipogenic mechanism of action and their impact on lipid metabolism remain unclear. In this study, we investigated the effect of citrus flavonoids, namely, hesperidin (HES), narirutin (NAR), nobiletin (NOB), sinensetin (SIN), and tangeretin (TAN), on preventing fat cell development by gene expression in 3T3-L1 adipocytes. Among the citrus flavonoids tested, HES and NAR significantly reduced fat storage and triglyceride levels and increased glucose uptake in 3T3-L1 adipocytes. Additionally, HES and NAR treatment increased the phosphorylation of AMP-activated protein kinase (AMPK) and acetyl-CoA carboxylase (ACC) while reducing the protein expression of 3-hydroxy-3-methylglutaryl CoA reductase (HMGCR). Furthermore, in silico docking revealed that flavonoids activate AMPK. RNA sequencing analysis demonstrated that citrus flavonoids normalized the expression of 40 genes, which were either upregulated by more than 2-fold or downregulated by less than 0.6-fold including Acadv1, Acly, Akr1d1, Awat1, Cyp27a1, Decr1, Dhrs4, Elovl3, Fasn, G6pc, Gba, Hmgcs1, Mogat2, Lrp5, Sptlc3, and Snca to levels comparable to the control group. Altogether, HES and NAR among five citrus flavonoids showed antiadipogenic effects by regulating the expression of specific lipid metabolism genes partially restored to control levels in 3T3-L1 cells.

Wild Asparagus Shoots Constitute a Healthy Source of Bioactive Compounds

Wild Asparagus shoots are consumed worldwide, although most species remain understudied. In this work, a total of four wild Asparagus species were collected from different locations and analyzed compared with farmed A. officinalis. Shoots were screened for (i) phenolic compounds by HPLC-DAD and LC-MS; (ii) total phenolic acids and total flavonoid content by the Folin-Ciocalteu and aluminum chloride methods; (iii) vitamin C by HPLC-DAD; (iv) antioxidant activity by the DPPH and ABTS•+ methods; and (v) the in vitro antiproliferative activities against HT-29 colorectal cancer cells by the MTT assay. Phenolics ranged from 107.5 (A. aphyllus) to 605.4 mg/100 g dry weight (dw) (A. horridus). Vitamin C ranged from 15.8 (A. acutifolius) to 22.7 mg/100 g fresh weight (fw) (A. officinalis). The antioxidant activity was similar in all species, standing out in A. officinalis with 5.94 (DPPH) and 4.64 (ABTS) mmol TE/100 g dw. Among phenolics, rutin reached the highest values (574 mg/100 g dw in A. officinalis), followed by quercetin, nicotiflorin, asterin, and narcissin. The MTT assay revealed the inhibitory effects of ethanol extracts against HT-29 cancer cells, highlighting the cell growth inhibition exercised by A. albus (300 µg/mL after 72 h exposure to cells). This work improves knowledge on the phytochemicals and bioactivities of the shoots of wild Asparagus species and confirms their suitability for use as functional foods.

Influence of storage variables on the antioxidant and antitumor activities, phenolic compounds and vitamin C of an agglomerate of Andean berries

Berry consumption is increasing worldwide due to their high content of bioactive compounds. However, such fruits have a very short shelf life. To avoid this drawback and to offer an effective alternative for its consumption at any time of the year, an agglomerated berry powder mix (APB) was developed. The aim of this work was to evaluate the stability of APB during a 6-months-period storage at 3 temperatures. The stability of APB was determined by moisture, a_w, antioxidant activity, total phenolics, total anthocyanins, vitamin C, color, phenolic profiles, and MTT assay. APB showed differences in antioxidant activity between 0 and 6 months. It experimented non-enzymatic browning, which was more remarkable at 35 °C. APB at time 0 exhibited growth inhibitory effects against HT-29 human cancer cells. Most properties were significantly modified by storage temperature and time, which induces a significant decreasing of bioactive compounds.

Differential Lipid Accumulation on HepG2 Cells Triggered by Palmitic and Linoleic Fatty Acids Exposure

Lipid metabolism pathways such as β-oxidation, lipolysis and, lipogenesis, are mainly associated with normal liver function. However, steatosis is a growing pathology caused by the accumulation of lipids in hepatic cells due to increased lipogenesis, dysregulated lipid metabolism, and/or reduced lipolysis. Accordingly, this investigation hypothesizes a selective in vitro accumulation of palmitic and linoleic fatty acids on hepatocytes. After assessing the metabolic inhibition, apoptotic effect, and reactive oxygen species (ROS) generation by linoleic (LA) and palmitic (PA) fatty acids, HepG2 cells were exposed to different ratios of LA and PA to study the lipid accumulation using the lipophilic dye Oil Red O. Lipidomic studies were also carried out after lipid isolation. Results revealed that LA was highly accumulated and induced ROS production when compared to PA. Lipid profile modifications were observed after LA:PA 1:1 (v/v) exposure, which led to a four-fold increase in triglycerides (TGs) (mainly in linoleic acid-containing species), as well as a increase in cholesterol and polyunsaturated fatty acids (PUFA) content when compared to the control cells. The present work highlights the importance of balancing both PA and LA fatty acids concentrations in HepG2 cells to maintain normal levels of free fatty acids (FFAs), cholesterol, and TGs and to minimize some of the observed in vitro effects (i.e., apoptosis, ROS generation and lipid accumulation) caused by these fatty acids.

Thermo-TRP channels are involved in BAT thermoregulation in cold-acclimated Brandt's voles

Transient receptor potential (TRP) channels, which can sense temperature, pressure and mechanical stimuli, were involved in many physiological and biochemical reactions. Whether thermosensitive TRP channels (Thermo-TRPs) are involved in thermoregulation in small mammals is still not clear. We measured the changes of thermo-TRPs at 4 °C, 23 °C and 30 °C in Brandt's voles (Lasiopodomys brandtii) to test the hypothesis that Thermo-TRPs are involved in cold-induced thermogenesis of brown adipose tissue (BAT) in small mammals. Results showed that air temperatures had no effect on body mass and rectal temperature, but the food intake and basal metabolic rate (BMR) in the 4 °C group were significantly higher than in the 30 °C group. Compared with 30 °C group, the protein contents of uncoupling protein 1(UCP1), TRP vanilloid 2 (TRPV2), TRP ankyrin 1 (TRPA1), TRP melastatin 2 (TRPM2), silent Information Regulator T1 (SIRT1), AMP-activated protein kinase (AMPK) and Calcium/calmodulin-dependent protein kinase II (CaMKII) in BAT increased significantly in 4 °C group, but there was no significant difference in the protein content of Thermo-TRPs in the hypothalamus among groups. Further, the expression of PRDM16 (PR domain containing 16) in inguinal white adipose tissue (iWAT) at 4 °C was significantly higher than that at 30 °C, but no difference was observed in the expression of other browning-related genes or TRPV2. In conclusion, TRP channels may participate in BAT thermoregulation through the CaMKII, AMPK, SIRT1 and UCP1 pathway in cold-acclimated Brandt's voles.

Selected Soybean Varieties Regulate Hepatic LDL-Cholesterol Homeostasis Depending on Their Glycinin:β-Conglycinin Ratio

Clinical studies indicate that the consumption of soybean protein might reduce cholesterol and LDL levels preventing the development of atherosclerotic cardiovascular diseases. However, soybean variety can influence soybean protein profile and therefore affect soybean protein health-promoting properties. This study investigated the composition and effects of nineteen soybean varieties digested under simulated gastrointestinal conditions on hepatic cholesterol metabolism and LDL oxidation in vitro. Soybean varieties exhibited a differential protein hydrolysis during gastrointestinal digestion. Soybean varieties could be classified according to their composition (high/low glycinin:β-conglycinin ratio) and capacity to inhibit HMGCR (IC50 from 59 to 229 µg protein mL−1). According to multivariate analyses, five soybean varieties were selected. These soybean varieties produced different peptide profiles and differently reduced cholesterol concentration (43−55%) by inhibiting HMGCR in fatty-acid-stimulated HepG2 hepatocytes. Selected digested soybean varieties inhibited cholesterol esterification, triglyceride production, VLDL secretion, and LDL recycling by reducing ANGPTL3 and PCSK9 and synchronously increasing LDLR expression. In addition, selected soybean varieties hindered LDL oxidation, reducing the formation of lipid peroxidation early (conjugated dienes) and end products (malondialdehyde and 4-hydroxynonenal). The changes in HMGCR expression, cholesterol esterification, triglyceride accumulation, ANGPTL3 release, and malondialdehyde formation during LDL oxidation were significantly (p < 0.05) correlated with the glycinin:β-conglycinin ratio. Soybean varieties with lower glycinin:β-conglycinin exhibited a better potential in regulating cholesterol and LDL homeostasis in vitro. Consumption of soybean flour with a greater proportion of β-conglycinin may, consequently, improve the potential of the food ingredient to maintain healthy liver cholesterol homeostasis and cardiovascular function.

Phloridzin Highly Accumulated in Malus rockii Rehder and Its Structure Revision and Hypolipidemic Activity

Phloridzin is a lead compound of the prestigious antidiabetic gliflozins. The present study found that phloridzin highly accumulated in Malus rockii Rehder. The content of phloridzin in M. rockii was the highest among wild plants, with the percentage of 15.54% in the dry leaves. The structure of phloridzin was revised by proton exchange experiments and extensive 2D NMR spectra. Phloridzin exhibited significant hypolipidemic activity in golden Syrian hamsters maybe by increasing the expression of CYP7A1, at the doses of 50 mg/kg and 200 mg/kg. The total performance of anti-hyperlipidemic effect of phloridzin may be superior to that of lovastatin, though lovastatin was more active than phloridzin. In addition, phloridzin exhibited moderate antimalarial activity with inhibition ratio of 31.3 ± 10.9% at a dose of 25 mg/kg/day, and showed moderate analgesic activity with 28.0% inhibition at a dose of 50 mg/kg.

Metformin enhances LDL-cholesterol uptake by suppressing the expression of the pro-protein convertase subtilisin/kexin type 9 (PCSK9) in liver cells

PURPOSE

Metformin (MF) intake associates with reduced levels of circulating low-density lipoprotein-cholesterol (LDL-C). This has been attributed to the activation of AMPK, which differentially regulates the expression of multiple genes involved in cholesterol synthesis and trafficking. However, the exact mechanism underlying the LDL-C lowering effect of MF remains ambiguous.

METHODS

MF-treated Hep-G2 and HuH7 cells were evaluated for cell viability and the expression status of key lipid metabolism-related genes along with LDL-C uptake efficiency.

RESULTS

MF treatment resulted in decreased expression and secretion of PCSK9, increased expression of LDLR and enhanced LDL-C uptake in hepatocytes. It also resulted in increased expression of activated AMPK (p-AMPK) and decreased expression of SREBP2 and HNF-1α proteins. Transcriptomic analysis of MF-treated Hep-G2 cells confirmed these findings and showed that other key lipid metabolism-related genes including those that encode apolipoproteins (APOB, APOC2, APOC3 and APOE), MTTP and LIPC are downregulated. Lastly, MF treatment associated with reduced HMG-CoA reductase expression and activity.

CONCLUSIONS

These findings suggest that MF treatment reduces circulating LDL-C levels by suppressing PCSK9 expression and enhancing LDLR expression; hence the potential therapeutic utility of MF in hypercholesterolemia.

The Activity of Ten Natural Extracts Combined in a Unique Blend to Maintain Cholesterol Homeostasis-In Vitro Model

BACKGROUND

Hypercholesterolemia is a major cause of cardiovascular disease and statins, the HMGCoA inhibitors, are the most prescribed drugs. Statins reduce the production of hepatic cholesterol, leading to greater expression of the LDL receptor and greater absorption of circulating LDL, reducing peripheral LDL levels. Unfortunately, statins are believed to induce myopathy and other severe diseases. To overcome this problem, safe nutraceuticals with the same activity as statins could hold great promise in the prevention and treatment of hypercholesterolemia. In this study, the anti-cholesterol efficacy of a new nutraceutical, called Esterol10^®, was evaluated.

METHODS

HepG2 cells were used to study the biological mechanisms exerted by Esterol10^® analyzing different processes involved in cholesterol metabolism, also comparing data with Atorvastatin.

RESULTS

Our results indicate that Esterol10^® leads to a reduction in total hepatocyte cholesterol and an improvement in the biosynthesis of free cholesterol and bile acids. Furthermore, the anti-cholesterol activity of Esterol10^® was also confirmed by the modulation of the LDL receptor and by the accumulation of lipids, as well as by the main intracellular pathways involved in the metabolism of cholesterol.

CONCLUSIONS

Esterol10^® is safe and effective with anti-cholesterol activity, potentially providing an alternative therapy to those based on statins for hypercholesterolemia disease.

Adipogenesis and therapeutic potentials of antiobesogenic phytochemicals: Insights from preclinical studies

Obesity is one of the most serious public health problems in both developed and developing countries in recent years. While lifestyle and diet modifications are the most important management strategies of obesity, these may be insufficient to ensure long-term weight reduction in certain individuals and alternative strategies including pharmacotherapy need to be considered. However, drugs option remains limited due to low efficacy and adverse effects associated with their use. Hence, identification of safe and effective alternative therapeutic agents remains warranted to combat obesity. In recent years, bioactive phytochemicals are considered as valuable sources for the discovery of new pharmacological agents for the treatment of obesity. Adipocyte hypertrophy and hyperplasia increases with obesity and undergo molecular and cellular alterations that can affect systemic metabolism giving rise to metabolic syndrome and comorbidities such as type 2 diabetes and cardiovascular diseases. Many phytochemicals have been reported to target adipocytes by inhibiting adipogenesis, inducing lipolysis, suppressing the differentiation of preadipocytes to mature adipocytes, reducing energy intake, and boosting energy expenditure mainly in vitro and in animal studies. Nevertheless, further high-quality studies are needed to firmly establish the clinical efficacy of these phytochemicals. This review outlines common pathways involved in adipogenesis and phytochemicals targeting effector molecules of these pathways, the challenges faced and the way forward for the development of phytochemicals as antiobesity agents.

Polyphenols and their anti-obesity role mediated by the gut microbiota: a comprehensive review

Obesity is a global public health problem that results in chronic pathologies such as diabetes, cardiovascular diseases, and cancer. The treatment approach based on energy restriction and promotion of physical activity is ineffective in the long term. Due to the high prevalence of this pathology, complementary treatments such as brown adipose tissue activation (BAT) and white adipose tissue browning (WAT) have been proposed. Dietary polyphenols are plant secondary metabolites that can stimulate browning and thermogenesis of adipose tissue. They have also been shown to prevent body weight gain, and decrease systemic inflammation produced by high-fat diets. Ingested dietary polyphenols that reach the colon are metabolized by the gut microbiota (GM), regulating its composition and generating a great array of metabolites. GM is involved in the production of short chain fatty acids and secondary bile salts that regulate energetic metabolism. The alteration in the composition of GM observed in metabolic diseases such as obesity and type 2 diabetes can be attenuated by polyphenols. Recent studies support the hypothesis that GM would mediate WAT browning and BAT thermogenesis activation induced by polyphenol administration. Together, these results indicate that GM in the presence of polyphenols plays a fundamental role in the control of obesity possible through BAT activation.

Protective Effects of Morus nigra and Its Phytochemicals against Hepatotoxicity: A Review of Preclinical Studies

BACKGROUND

Our liver has a variety of vital functions including removing poisons, storing energy, immunological roles, and secretory and excretory functions. It may face some kinds of diseases caused by viruses, hepatotoxic chemicals, drugs, alcohol, and inherited disorders. Oxidative stress and inflammation are in the core of mechanisms of liver damages induced by viruses or chemical agents.

SUMMARY

Morus nigra (M. nigra), generally known as black mulberry, exhibited wide-spectrum pharmacological effects including antidiabetic, antinociceptive, anticancer, and hepatoprotective activities. Different parts of this plant particularly the fruit and leaf have shown beneficial effects on hepatocytes in cell culture and animal models of liver damages induced by chemicals (e.g., CCl4), drugs (e.g., paracetamol), diet (e.g., high fat), diabetes, etc. The beneficial effects of M. nigra on the liver are attributed to the presence of considerable amounts of phenolic compounds such as anthocyanins, flavonols, and phenolic acids. The present review is aimed to focus on the hepatoprotective activities of M. nigra and its phytochemicals and the mechanisms responsible for these activities. Key Messages: The evidence reviewed in this study can help design clinical trials on M. nigra in patients with liver disorders and develop a hepatoprotective herbal medicine.

Strawberry-Derived Exosome-Like Nanoparticles Prevent Oxidative Stress in Human Mesenchymal Stromal Cells

Plant-derived exosome-like nanovesicles (EPDENs) have recently been isolated and evaluated as potential bioactive nutraceutical biomolecules. It has been hypothesized that EPDENs may exert their activity on mammalian cells through their specific cargo. In this study, we isolated and purified EPDENs from the strawberry juice of Fragaria x ananassa (cv. Romina), a new cultivar characterized by a high content of anthocyanins, folic acid, flavonols, and vitamin C and an elevated antioxidant capacity. Fragaria-derived EPDENs were purified by a series of centrifugation and filtration steps. EPDENs showed size and morphology similar to mammalian extracellular nanovesicles. The internalization of Fragaria-derived EPDENs by human mesenchymal stromal cells (MSCs) did not negatively affect their viability, and the pretreatment of MSCs with Fragaria-derived EPDENs prevented oxidative stress in a dose-dependent manner. This is possibly due to the presence of vitamin C inside the nanovesicle membrane. The analysis of EPDEN cargo also revealed the presence of small RNAs and miRNAs. These findings suggest that Fragaria-derived EPDENs may be considered nanoshuttles contained in food, with potential health-promoting activity.

Piceatannol promotes hepatic and renal AMPK/SIRT1/PGC-1α mitochondrial pathway in rats exposed to reserpine or gamma-radiation

Human exposure to radio-therapeutic doses of gamma rays can produce late effects, which negatively affect cancer patients' quality of life, work prospects, and general health. This study was performed to explore the role of Piceatannol (PIC) in the process of "mitochondrial biogenesis" signaling pathway as possible management of disturbances induced in stressed animal model(s) either by gamma-irradiation (IR) or administration of reserpine (RES); as a mitochondrial complex-I inhibitor. PIC (10 mg/kg BW/day; orally) were given to rats for 7 days, after exposure to an acute dose of γ-radiation (6 Gy), or after a single reserpine injection (1 g/kg BW; sc). Compared to reserpine or γ-radiation, PIC has attenuated hepatic and renal mitochondrial oxidative stress denoted by the significant reduction in the content of lipid peroxides and NO with significant induction of SOD, CAT, GSH-PX, and GR activities. PIC has also significantly alleviated the increase of the inflammatory markers, TNF-α and IL-6 and apoptotic markers, cytochrome c, and caspase-3. The decrease of oxidative stress, inflammation, and apoptotic responses were linked to a significant amelioration in mitochondrial biogenesis demonstrated by the increased expression and proteins' tissue contents of SIRT1/p38-AMPK, PGC-1α signaling pathway. The results are substantiated by the significant amelioration in mitochondrial function verified by the higher levels of ATP content, and complex I activity, besides the improvement of hepatic and renal functions. Additionally, histopathological examinations of hepatic and renal tissues showed that PIC has modulated tissue architecture after reserpine or gamma-radiation-induced tissue damage. Piceatannol improves mitochondrial functions by regulating the oxidant/antioxidant disequilibrium, the inflammatory and apoptotic responses, suggesting its possible use as adjuvant therapy in radio-therapeutic protocols to attenuate hepatic and renal injuries.

Dietary Ginsenoside T19 Supplementation Regulates Glucose and Lipid Metabolism via AMPK and PI3K Pathways and Its Effect on Intestinal Microbiota

Ginseng, as a functional food, is widely used worldwide because of its multifarious benefits. Studies have verified that 25-hydroxyl-protopanaxatriol (T19) is a new ginsenoside from ginseng, which had an important inhibitory effect on α-glucosidase and protein tyrosine phosphatase 1B in vitro. This study aims to assess the regulation of T19 against glycolipid metabolism by insulin-resistant HepG2 cells and diabetes mice induced with high-fat diet combined with streptozotocin (STZ). T19 effectively lowered the levels of blood glucose and lipid, alleviated insulin resistance, and improved histological pathology of liver and pancreas. Further study demonstrated that regulation of AMP-activated protein kinase- and phosphoinositide-3-kinase-signaling pathways was involved in the potential mechanism of T19 efficiency. Simultaneously, high-throughput sequencing of 16S rDNA revealed that T19 remarkably ameliorated the high-fat diet/STZ-induced disorders of intestinal microbiota by decreasing the value of Firmicutes/Bacteroidetes, and remarkably raised the relative abundance of the Lachnospiraceae family, which are the beneficial bacteria that can regulate glucose and lipid metabolism. The results may provide clues for further understanding the mechanism of T19 in regulating glycolipid metabolism, and may provide a scientific basis for ginseng as a potential dietary food to prevent metabolic diseases.

Anthocyanin-rich fraction from Thai berries interferes with the key steps of lipid digestion and cholesterol absorption

Several studies have documented the hypolipidemic effect of anthocyanin-rich plants in vitro and in vivo. The objective of this study was to elucidate the inhibitory activity of anthocyanin-rich fraction from Thai berries against fat digestive enzymes. The ability of Thai berries to bind bile acid, disrupt cholesterol micellization and the cholesterol uptake into Caco-2 cells was also determined. The content of total phenolics, flavonoid and anthocyanin in Prunus domestica L. (TPE), Antidesma bunius (L.) Spreng, Syzygium cumini (L.) Skeels, and Syzygium nervosum A. Cunn. Ex DC was 222.7–283.5 mg gallic acid equivalents, 91.2–184.3 mg catechin equivalents, and 37.9–49.5 mg cyanidin-3-glucoside equivalents/g extract, respectively. The anthocyanin-rich fraction of all extracts inhibited pancreatic lipase and cholesterol esterase with the IC₅₀ values of 90.6–181.7 μg/mL and 288.7–455.0 μg/mL, respectively. Additionally, all extracts could bind primary and secondary bile acids (16.4–36.6%) and reduce the solubility of cholesterol in artificial micelles (53.0–67.6%). Interestingly, TPE was the most potent extract on interfering the key steps of lipid digestion among the tested extracts. In addition, TPE (0.10–0.50 mg/mL) significantly reduced the cholesterol uptake into Caco-2 cells in a concentration-dependent manner. These results demonstrate a new insight into the role of anthocyanin-rich Thai berry extract on interfering the key steps of lipid digestion and absorption.

Effects of ozone treatment on the antioxidant capacity of postharvest strawberry

Strawberries are highly popular around the world because of their juicy flesh and unique taste. However, they are delicate and extremely susceptible to peroxidation of their membrane lipids during storage, which induces water loss and rotting of the fruit. This study investigated the effects of ozone treatment on the physiological traits, active oxygen metabolism, and the antioxidant properties of postharvest strawberry. The results revealed that the weight loss (WL) and respiration rate (RR) of strawberry were inhibited by ozone treatment (OT), while the decline of firmness (FIR) and total soluble solids (TSS) were delayed. Ozone also reduced the generation rate of superoxide radical anions , and the content of hydrogen peroxide (H₂O₂) enhanced the activity of superoxidase (SOD), catalase (CAT), ascorbate peroxidase (APX), and monodehydroascorbate reductase (MDHAR), as well as promoted the accumulation of ascorbic acid (ASA), glutathione (GSH), and ferric reducing/antioxidant power (FRAP). In addition, a total of 29 antioxidant-related proteins were changed between the OT group and control (CK) group as detected by label-free proteomics during the storage time, and the abundance associated with ASA–GSH cycle was higher in the OT group at the later stage of storage, and the qRT-PCR results were consistent with those of proteomics. The improvement of the antioxidant capacity of postharvest strawberry treated with ozone may be achieved by enhancing the activity of the antioxidant enzymes and increasing the expression of the antioxidant proteins related to the ascorbic acid–glutathione (ASA–GSH) cycle.

Strawberries are highly popular around the world because of their juicy flesh and unique taste.

Strawberry (Fragaria × ananassa cv. Romina) methanolic extract promotes browning in 3T3-L1 cells

In recent years, the conversion of white adipocytes to brown-like adipocytes by pharmacological and dietary compounds has gained attention as an effective strategy to fight obesity. Strawberry bioactive compounds present several biological activities including antioxidant, anti-inflammatory, anti-cancer, anti-atherosclerotic and antiadipogenic properties. However, to the best of our knowledge, the possible role of strawberry bioactive compounds in white adipose tissue (WAT) browning has never been explored. Our results demonstrated that a strawberry methanolic extract (SE) significantly reduced 3T3-L1 pre-adipocytes differentiation, and down-regulated the mRNA expression of the adipogenic transcription factors CCAAT/enhancer-binding protein (C/REB- α) and peroxisome proliferation-activated receptor (PPAR-γ). It also down-regulated the mRNA expression of resistin and angiotensinogen, two genes considered as markers of white adipocytes, while increased the mRNA expression of pyruvate dehydrogenase lipoamide kinase isozyme 4 (PDK4) and uncoupling protein 1 (UCP1) which, conversely, are brown adipocyte-specific markers. Likewise, SE stimulated AMP-activated protein kinase (AMPKα), sirtuin 1 (Sirt1) and the peroxisome proliferator activated receptor gamma coactivator 1-alpha (PGC-1α), suggesting a possible increase in mitochondrial biogenesis. It also stimulated oxygen consumption rate and uncoupled respiration. Taken together, all these results suggest that SE induces brown fat-like phenotype in 3T3-L1 cells and may have potential therapeutic implications for treatment and/or prevention of obesity.

Select Polyphenol-Rich Berry Consumption to Defer or Deter Diabetes and Diabetes-Related Complications

Berries are considered "promising functional fruits" due to their distinct and ubiquitous therapeutic contents of anthocyanins, proanthocyanidins, phenolic acids, flavonoids, flavanols, alkaloids, polysaccharides, hydroxycinnamic, ellagic acid derivatives, and organic acids. These polyphenols are part of berries and the human diet, and evidence suggests that their intake is associated with a reduced risk or the reversal of metabolic pathophysiologies related to diabetes, obesity, oxidative stress, inflammation, and hypertension. This work reviewed and summarized both clinical and non-clinical findings that the consumption of berries, berry extracts, purified compounds, juices, jams, jellies, and other berry byproducts aided in the prevention and or otherwise management of type 2 diabetes mellitus (T2DM) and related complications. The integration of berries and berries-derived byproducts into high-carbohydrate (HCD) and high-fat (HFD) diets, also reversed/reduced the HCD/HFD-induced alterations in glucose metabolism-related pathways, and markers of oxidative stress, inflammation, and lipid oxidation in healthy/obese/diabetic subjects. The berry polyphenols also modulate the intestinal microflora ecology by opposing the diabetic and obesity rendered symbolic reduction of Bacteroidetes/Firmicutes ratio, intestinal mucosal barrier dysfunction-restoring bacteria, short-chain fatty acids, and organic acid producing microflora. All studies proposed a number of potential mechanisms of action of respective berry bioactive compounds, although further mechanistic and molecular studies are warranted. The metabolic profiling of each berry is also included to provide up-to-date information regarding the potential anti-oxidative/antidiabetic constituents of each berry.

Hydroxycitric acid potentiates the cytotoxic effect of tamoxifen in MCF-7 breast cancer cells through inhibition of ATP citrate lyase

Hydroxycitric acid (HCA), a dietary-derived weight loss supplement, competitively inhibits ATP citrate lyase (ACLY). Tamoxifen (TAM) is the most frequently used therapy for estrogen receptor (ER)-positive breast cancer patients, but its application was restricted due to efficacy related issues. Lipid metabolic reprogramming plays a key role in cancer progression and response to treatment. This study will test the hypothesis that targeting lipid metabolic enzymes could enhance TAM effect against breast cancer cells. MCF-7 ER-positive breast cancer cell line was used, and the cytotoxic effect of TAM treatment, alone and in combination with HCA was evaluated. Flowcytometric analysis of apoptosis following TAM and/or HCA treatment was additionally performed. Besides, the effects of TAM and/or HCA on ACLY, acetyl CoA carboxylase alpha (ACC-α) and fatty acid synthase (FAS) expression were investigated. Likewise, expression of ER-α protein through TAM and/or HCA treatment was examined. Cell contents of cholesterol and triglyceride were quantified. Treatment with TAM or HCA significantly reduced cell viability in a concentration-dependent manner whereas co-treatment synergistically reduced cell viability, promoted apoptosis, and decreased the expression of ACLY, ACC-α, and FAS. Intracellular triglyceride and cholesterol were accumulated in response to treatment with TAM and/or HCA. Moreover, either solitary TAM or TAM/ HCA co-treatment increased ER-α protein levels non significantly. Our results revealed that TAM effects on breast cancer are mediated, in part, through the regulation of key genes involved in lipid metabolism. Accordingly, inhibition of ACLY by HCA might be beneficial to enhance the therapeutic index of TAM against breast cancer.

Phytotherapy using blueberry leaf polyphenols to alleviate non-alcoholic fatty liver disease through improving mitochondrial function and oxidative defense

BACKGROUND

Since non-alcoholic fatty liver disease (NAFLD) pathogenesis is multi-factorial, pharmacotherapy with a specific target commonly exhibits limited efficacy. Phytotherapy, whose therapeutic efficacy is based on the combined action of several active compounds, offers new treatment opportunity for NAFLD. As a representative, many natural polyphenols could be utilized in phytotherapy for NAFLD.

PURPOSE

In present work, we aimed to investigate the therapeutic effects and underlying mechanism of polyphenols in blueberry leaves (PBL) on NAFLD from a mitochondria-centric perspective since mitochondrial dysfunction could play a dominant role in NAFLD.

METHODS

Identification and quantification of PBL were performed using liquid chromatography coupled with tandem mass spectrometry. The beneficial effects, especially improving mitochondrial function, and potential mechanism of PBL on NAFLD were studied by in vitro and in vivo study.

RESULTS

Polyphenols were abundant in blueberry leaves making it advantaged in NAFLD phytotherapy. PBL effectively alleviated hepatic steatosis, oxidative stress and inflammation as indicated by both in vitro and in vivo study. Furthermore, PBL mediated improvement of mitochondrial dysfunction and antioxidant capability through activation of AMPK/PGC-1α/SIRT3 signaling axis.

CONCLUSION

Considering that mitochondrial dysfunction takes precedence over hepatic steatosis and induces NAFLD development, we conclude that PBL improve mitochondrial dysfunction and oxidative defense, subsequently alleviate hepatic steatosis, oxidative stress and inflammation, and eventually alleviate NAFLD.

Distribution of Flavan-3-ol Species in Ripe Strawberry Fruit Revealed by Matrix-Assisted Laser Desorption/Ionization-Mass Spectrometry Imaging

Flavan-3-ols, which comprise proanthocyanidins and their monomers, are major flavonoids in strawberries, and they have a wide range of biological activities and health benefits. However, their spatial distribution in strawberry fruit remains poorly understood. Therefore, we performed matrix-assisted laser desorption/ionization-mass spectrometry imaging (MALDI-MSI), to visualize flavan-3-ols in ripe strawberry fruit. Peaks matching the m/z values of flavan-3-ols [M − H]⁻ ions were detected in the negative ion mode using 1,5-diaminonaphthalene as matrix. Catechin and/or epicatechin, three B-type procyanidins, and two B-type propelargonidins were identified by MALDI-tandem MS. These flavan-3-ols were mainly distributed in the calyx, in and around the vascular bundles, and in the skin. In-source fragmentation of proanthocyanidins was determined using their standards, suggesting their distribution was mixed ion images of themselves, and fragment ions generated from those had a higher degree of polymerization. B-type procyanidins were predominantly distributed in the vascular bundles than in the skin, whereas B-type propelargonidins were almost equally distributed between the vascular bundles and skin, suggesting that their distribution patterns are different from the type of their flavan-3-ol monomers. Flavan-3-ols, especially B-type procyanidins, may help prevent pathogen infection not only in the skin but also in and around the vascular bundles.

The Positive Effects of Grifola frondosa Heteropolysaccharide on NAFLD and Regulation of the Gut Microbiota

Non-alcoholic fatty liver disease (NAFLD) is a major public health problem in many countries. In this study, the ability of Grifola frondosa heteropolysaccharide (GFP) to ameliorate NAFLD was investigated in rats fed a high-fat diet (HFD). The molecular mechanisms modulating the expression of specific gene members related to lipid synthesis and conversion, cholesterol metabolism, and inflammation pathways were determined. The components of the intestinal microflora in rats were analyzed by high-throughput next-generation 16S rRNA gene sequencing. Supplementation with GFP significantly increased the proportions of Allobaculum, Bacteroides, and Bifidobacterium and decreased the proportions of Acetatifactor, Alistipes, Flavonifractor, Paraprevotella, and Oscillibacter. In addition, Alistipes, Flavonifractor, and Oscillibacter were shown to be significant cecal microbiota according to the Spearman’s correlation test between the gut microbiota and biomedical assays (|r| > 0.7). Histological analysis and biomedical assays showed that GFP treatments could significantly protect against NAFLD. In addition, Alistipes, Flavonifractor, and Oscillibacter may play vital roles in the prevention of NAFLD. These results suggest that GFP could be used as a functional material to regulate the gut microbiota of NAFLD individuals.

Isolation of strawberry anthocyanin-rich fractions and their mechanisms of action against murine breast cancer cell lines

The aim of this study was the evaluation of the effects of strawberry anthocyanin extract treatment on two in vitro models of murine breast cancer cell lines, in an attempt to detect a specific pathway (AMP-activated protein kinase or AMPK) through which strawberries exert their anticancer activity. The anticancer activity of purified anthocyanin extracts from an Alba cultivar on two murine cancer cell lines, N202/1A (with high levels of the HER2/neu oncogene) and N202/1E (with low levels of the HER2/neu oncogene), was evaluated after 48 and 72 h of treatment. The cell viability and apoptosis, intracellular ROS rates, and cell oxidative damage were assessed. Western blot assays were performed to analyze the expression of several proteins related to apoptosis, autophagy, metastasis, the oxidative status, mitochondrial functionality, and the AMPK pathway. This study demonstrated that the anthocyanin extract of Alba strawberry shows an antiproliferative effect on cancer cells, through the induction of apoptosis and oxidative stress, by stimulating different molecular pathways. This study is one of the first studies that have tried to deepen the understanding of a candidate pathway for the explanation of the effects of strawberry on cancer cells. A relationship between the AMPK pathway and the anticancer effects of strawberries was demonstrated.

Ameliorative effects of black ginseng on nonalcoholic fatty liver disease in free fatty acid-induced HepG2 cells and high-fat/high-fructose diet-fed mice

Background

Black ginseng (BG) is a type of Korean ginseng prepared by steaming and drying raw ginseng to improve the saponin content. This study examined the effects of BG on nonalcoholic fatty liver disease (NAFLD) in HepG2 cells and diet-induced obese mice.

Methods

HepG2 cells were treated with free fatty acids to induce lipid accumulation before supplementation with BG. NAFLD-induced mice were fed different doses (0.5%, 1%, and 2%) of BG for 8 weeks.

Results

BG significantly reduced lipid accumulation and expression of lipogenic genes, peroxisome proliferator–activated receptor gamma, CCAAT/enhancer-binding protein alpha, sterol regulatory element-binding protein-1c, and fatty acid synthase in HepG2 cells, and the livers of mice fed a 45% high-fat diet with 10% fructose in the drinking water (HFHF diet). BG supplementation caused a significant reduction in levels of aspartate aminotransferase and alanine aminotransferase, while antioxidant enzymes activities were significantly increased in 45% high-fat diet with 10% fructose in the drinking water diet-fed mice. Expression of proliferator-activated receptor alpha and carnitine palmitoyltransferase I were upregulated at the transcription and translation levels in both HepG2 cells and diet-induced obese mice. Furthermore, BG-induced phosphorylation of AMP-activated protein kinase and acetyl CoA carboxylase in both models, suggesting its role in AMP-activated protein kinase activation and the acetyl CoA carboxylase signaling pathway.

Conclusion

Our results indicate that BG may be a potential therapeutic agent for the prevention of NAFLD.

Activating Effects of Phenolics from Apache Red Zea mays L. on Free Fatty Acid Receptor 1 and Glucokinase Evaluated with a Dual Culture System with Epithelial, Pancreatic, and Liver Cells

The aim was to characterize a phenolic-rich water extract from the pericarp of an improved genotype of Apache red maize (RPE) and evaluate its ability to activate the type 2 diabetes markers free fatty acid receptor 1 (GPR40) and glucokinase (GK) in vitro. The extract contained mainly phenolic acids, anthocyanins, and other flavonoids. RPE inhibited α-amylase (IC₅₀ = 88.3 μg/mL), α-glucosidase (IC₅₀ = 169.3 μg/mL), and reduced glucose transport in a Caco-2 cell monolayer (up to 25%). Furthermore, RPE activated GPR40 (EC₅₀ = 77.7 μg/mL) in pancreatic INS-1E cells and GK (EC₅₀ = 43.4 μg/mL) in liver HepG2 cells, potentially through allosteric modulation. RPE activated GPR40-related insulin secretory pathway and activated the glucose metabolism regulator AMPK (up to 78%). Our results support the hypothesis that foods with a high concentration of anthocyanins and phenolic acids, such as in the selected variety of maize used, could ameliorate obesity and type 2 diabetes comorbidities.

Ascorbic acid attenuates cell stress by activating the fibroblast growth factor 21/fibroblast growth factor receptor 2/adiponectin pathway in HepG2 cells

Increasing prevalence of obesity‑induced non‑alcoholic fatty liver disease (NAFLD) and non‑alcoholic steatohepatitis (NASH) has been reported. Ascorbic acid (AA), also known as vitamin C, an excellent antioxidant, has been shown to exert beneficial effects on NAFLD; however, the underlying mechanisms are yet to be fully elucidated. In the present study, the role of AA on cell stress in tumor necrosis factor α (TNFα)‑treated HepG2 cells was investigated. Our findings revealed that exposure to AA effectively ameliorated TNFα‑induced cell stresses, including hypoxia, inflammation and endoplasmic reticulum (ER) stress by reducing the expression of Hif1α and its target genes (glucose transporter 1), pro‑inflammatory genes (monocyte chemoattractant 1) and ER stress‑related genes (glucose‑regulated protein, 78 kDa). AA also decreased the protein level of HIF1α. Additionally, AA significantly increased the secretion of total adiponectin and high molecular weight (HMW) adiponectin. Mechanistically, AA was determined to increase the expression of fibroblast growth factor 21 (FGF21) and its receptor, fibroblast growth factor receptor 2 (FGFR2). Knockdown of FGFR2 not only decreased the levels of total adiponectin and HMW adiponectin, but almost abolished the beneficial effects of AA in ameliorating cell stress. Collectively, the findings of our study demonstrated that AA may attenuate hepatocyte stress induced by TNFα via activation of the FGF21/FGFR2/adiponectin pathway. This could a novel mechanism of action of AA, and its potential for the treatment of NAFLD/NASH.

Citrus peel flavonoids improve lipid metabolism by inhibiting miR-33 and miR-122 expression in HepG2 cells

Citrus plants are rich in flavonoids and beneficial for lipid metabolism. However, the mechanism has not been fully elucidated. Both citrus peel flavonoid extracts (CPFE) and a mixture of their primary flavonoid compounds, namely, nobiletin, tangeretin and hesperidin, citrus flavonoid purity mixture (CFPM), were found to have lipid-lowering effects on oleic acid-induced lipid accumulation in HepG2 cells. The carnitine palmitoyltransferase 1α (CPT1α) gene was markedly increased, while the fatty acid synthase (FAS) gene was significantly decreased by both CPFE and CFPM in oleic acid-treated HepG2 cells. Flavonoid compounds from citrus peel suppressed miR-122 and miR-33 expression, which were induced by oleic acid. Changes in miR-122 and miR-33 expression, which subsequently affect the expression of their target mRNAs FAS and CPT1α, are most likely the principal mechanisms leading to decreased lipid accumulation in HepG2 cells. Citrus flavonoids likely regulate lipid metabolism by modulating the expression levels of miR-122 and miR-33.

Strawberry Intake Ameliorates Oxidative Stress and Decreases GABA Levels Induced by High-Fat Diet in Frontal Cortex of Rats

It has been proposed that there is a correlation between high-fat diet (HFD), oxidative stress and decreased γ-aminobutyric acid (GABA) levels, but this has not been thoroughly demonstrated. In the present study, we determined the effects of strawberry extract intake on the oxidative stress and GABA levels in the frontal cortex (FC) of obese rats. We observed that an HFD increased lipid and protein oxidation, and decreased GABA levels. Moreover, UV-irradiated strawberry extract (UViSE) decreased lipid peroxidation but not protein oxidation, whereas non-irradiated strawberry extract (NSE) reduced protein oxidation but not lipid peroxidation. Interestingly, NSE increased GABA concentration, whereas UViSE was not as effective. In conclusion, our results suggest that an HFD increases oxidative damage in the FC, whereas strawberry extract intake may ameliorate the disturbances associated with HFD-induced oxidative damage.

Metabolomic study of bioactive compounds in strawberries preserved under controlled atmosphere based on GC-MS and DI-ESI-QqQ-TOF-MS

INTRODUCTION

The storage of the vegetables products in a controlled atmosphere (CA) with low O₂ and high CO₂ concentrations, reduces respiration rates and delays the ripening process, and in some cases, improves their quality and organoleptic properties.

OBJECTIVE

To obtain deep insight into strawberry fruit metabolic changes caused by these CA treatments.

METHODOLOGY

Freshly harvested strawberries were preserved under different atmospheres enriched with 10%, 20% and 30% of CO₂ , for 2 days at 0°C, containing in all the cases 5% of O₂ and were subjected to a metabolomic analysis based on gas chromatography-mass spectrometry (GC-MS) and direct-infusion with electrospray ionisation source equipped with triple quadrupole coupled to time of flight mass spectrometry (DI-ESI-QqQ-TOF-MS). Partial least square discriminant analysis (PLS-DA) was employed to compare the control and treated samples for the identification of altered metabolites.

RESULTS

Several metabolites related to CA treatment could be identified by databases and literature, which are mainly sugars, organic acids and phenolic compounds (bioactive compounds).

CONCLUSIONS

Good correlation coefficients were obtained between discriminant metabolites and fruit quality parameters. These results suggest that treated strawberries under CA could be considered as bioactive healthy compounds, suggesting that treated strawberries under CA could be used as raw material for the preparation and formulation of food supplements and nutraceutical products.

Lonicera caerulea Extract Attenuates Non-Alcoholic Fatty Liver Disease in Free Fatty Acid-Induced HepG2 Hepatocytes and in High Fat Diet-Fed Mice

Honeyberry (Lonicera caerulea) has been used for medicinal purposes for thousands of years. Its predominant anthocyanin, cyanidin-3-O-glucoside (C3G), possesses antioxidant and many other potent biological activities. We aimed to investigate the effects of honeyberry extract (HBE) supplementation on HepG2 cellular steatosis induced by free fatty acids (FFA) and in diet-induced obese mice. HepG2 cells were incubated with 1 mM FFA to induce lipid accumulation with or without HBE. Obesity in mice was induced by a 45% high fat diet (HFD) for 6 weeks and subsequent supplementation of 0.5% HBE (LH) and 1% HBE (MH) for 6 weeks. HBE suppressed fatty acid synthesis and ameliorated lipid accumulation in HepG2 cells induced by FFA. Moreover, HBE also decreased lipid accumulation in the liver in the supplemented HBE group (LH, 0.5% or MH, 1%) compared with the control group. The expressions of adipogenic genes involved in hepatic lipid metabolism of sterol regulatory element-binding protein-1 (SREBP-1c), CCAAT/enhancer-binding protein alpha (C/EBPα), peroxisome proliferator-activated receptor gamma (PPARγ), and fatty acid synthase (FAS) were decreased both in the HepG2 cells and in the livers of HBE-supplemented mice. In addition, HBE increased mRNA and protein levels of carnitine palmitoyltransferase (CPT-1) and peroxisome proliferator-activated receptor α (PPARα), which are involved in fatty acid oxidation. Furthermore, HBE treatment increased the phosphorylation of AMP-activated protein kinase (AMPK) and Acetyl-CoA Carboxylase (ACC). Honeyberry effectively reduced triglyceride accumulation through down-regulation of hepatic lipid metabolic gene expression and up-regulation of the activation of AMPK and ACC signaling in both the HepG2 cells as well as in livers of diet-induced obese mice. These results suggest that HBE may actively ameliorate non-alcoholic fatty liver disease.

Ginkgolide C reduced oleic acid-induced lipid accumulation in HepG2 cells

Ginkgolide C, isolated from Ginkgo biloba, is a diterpene lactone that has multiple biological functions and can improve Alzheimer disease and platelet aggregation. Ginkgolide C also inhibits adipogenesis in 3T3-L1 adipocytes. The present study evaluated whether ginkgolide C reduced lipid accumulation and regulated the molecular mechanism of lipogenesis in oleic acid-induced HepG2 hepatocytes. HepG2 cells were treated with 0.5 mM oleic acid for 48 h to induce a fatty liver cell model. Then, the cells were exposed to various concentrations of ginkgolide C for 24 h. Staining with Oil Red O and the fluorescent dye BODIPY 493/503 revealed that ginkgolide C significantly reduced excessive lipid accumulation in HepG2 cells. Ginkgolide C decreased peroxisome proliferator-activated receptor γ and sterol regulatory element-binding protein 1c to block the expression of fatty acid synthase. Ginkgolide C treatment also promoted the expression of adipose triglyceride lipase and the phosphorylation level of hormone-sensitive lipase to enhance the decomposition of triglycerides. In addition, ginkgolide C stimulated CPT-1 to activate fatty acid β-oxidation, significantly increased sirt1 and phosphorylation of AMP-activated protein kinase (AMPK), and decreased expression of acetyl-CoA carboxylase for suppressed fatty acid synthesis in hepatocytes. Taken together, our results suggest that ginkgolide C reduced lipid accumulation and increased lipolysis through the sirt1/AMPK pathway in oleic acid-induced fatty liver cells.

Pseudolaric acid B exhibits anti-cancer activity on human hepatocellular carcinoma through inhibition of multiple carcinogenic signaling pathways

BACKGROUND

Pseudolaric acid B (PAB), a diterpene acid isolated from the root bark of Pseudolarix kaempferi, exhibits a potent anti-cancer activity in a variety of tumor cells.

PURPOSE

The present study was designed to evaluate the anti-cancer effects of PAB on hepatocellular carcinoma (HCC) cell lines in vitro, and to explore the underlying mechanism.

METHODS

The anti-proliferative activity of PAB on HCC cells were assessed via sulforhodamine B staining, colony formation, cell cycle analysis, respectively. Apoptosis was detected using Annexin V/propidium iodide double staining and diamidino-phenyl-indole staining, respectively. Protein expression regulated by PAB treatment was tested by western blotting.

RESULTS

The present results showed that PAB significantly inhibited the proliferation of HepG2, SK-Hep-1, and Huh-7 HCC cell lines in vitro with IC₅₀ values of 1.58, 1.90, and 2.06 μM, respectively. Furthermore, PAB treatment repressed the colony formation in HepG2, SK-Hep-1, and Huh-7 HCC cell lines. Flow cytometry analysis revealed that PAB caused an obvious cell cycle arrest in G2/M phase and induced apoptosis with the induction of p21, Bax, cleaved-caspase-3, and cleaved-PARP in human HepG2 and SK-Hep-1 cells. Mechanistically, PAB treatment down-regulated the phosphorylation of STAT3, ERK1/2, and Akt. Moreover, abnormal GSK-3β/β-catenin signaling in HepG2 cells was remarkably suppressed by PAB treatment. Finally, proliferation markers including cyclin D1 and c-Myc, and anti-apoptosis proteins such as Bcl-2 and survivin were also down-regulated by PAB treatment in HepG2 cells.

CONCLUSION

Taken together, our results suggest that PAB exerts anti-cancer activity in HCC cells through inhibition of STAT3, ERK1/2, Akt, and GSK-3β/β-catenin carcinogenic signaling pathways, and may be used as a phytomedicine in the treatment of HCC.

Relevance of functional foods in the Mediterranean diet: the role of olive oil, berries and honey in the prevention of cancer and cardiovascular diseases

The traditional Mediterranean diet (MedDiet) is a well-known dietary pattern associated with longevity and improvement of life quality as it reduces the risk of the most common chronic pathologies, such as cancer and cardiovascular diseases (CVDs), that represent the principal cause of death worldwide. One of the most characteristic foods of MedDiet is olive oil, a very complex matrix, which constitutes the main source of fats and is used in the preparation of foods, both raw as an ingredient in recipes, and in cooking. Similarly, strawberries and raspberries are tasty and powerful foods which are commonly consumed in the Mediterranean area in fresh and processed forms and have attracted the scientific and consumer attention worldwide for their beneficial properties for human health. Besides olive oil and berries, honey has lately been introduced in the MedDiet thanks to its relevant nutritional, phytochemical and antioxidant profile. It is a sweet substance that has recently been classified as a functional food. The aim of this review is to present and discuss the recent evidence, obtained from in vitro, in vivo and epidemiological studies, on the potential roles exerted by these foods in the prevention and progression of different types of cancer and CVDs.

Caffeic Acid Targets AMPK Signaling and Regulates Tricarboxylic Acid Cycle Anaplerosis while Metformin Downregulates HIF-1α-Induced Glycolytic Enzymes in Human Cervical Squamous Cell Carcinoma Lines

The small molecules, natural antioxidant Caffeic Acid (trans-3,4-Dihydroxycinnamic acid CA) and anti-diabetic drug Metformin (Met), activate 5&prime;-adenosine monophosphate-activated protein kinase (AMPK) and interfere with metabolic reprogramming in human cervical squamous carcinoma cells. Here, to gain more insight into the ability of CA, Met and the combination of both compounds to impair aerobic glycolysis (the &ldquo;Warburg effect&rdquo;) and disrupt bioenergetics of cancer cells, we employed the cervical tumor cell lines C-4I and HTB-35/SiHa. In epithelial C-4I cells derived from solid tumors, CA alleviated glutamine anaplerosis by downregulation of Glutaminase (GLS) and Malic Enzyme 1 (ME1), which resulted in the reduction of NADPH levels. CA treatment of the cells altered tricarboxylic acid (TCA) cycle supplementation with pyruvate via Pyruvate Dehydrogenase Complex (PDH), increased ROS formation and enhanced cell death. Additionally, CA and CA/Met evoked intracellular energetic stress, which was followed by activation of AMPK and the impairment of unsaturated FA de novo synthesis. In invasive HTB-35 cells, Met inhibited Hypoxia-inducible Factor 1 (HIF-1&alpha;) and suppressed the expression of the proteins involved in the &ldquo;Warburg effect&rdquo;, such as glucose transporters (GLUT1, GLUT3) and regulatory enzymes of glycolytic pathway Hexokinase 2 (HK2), 6-Phosphofructo-2-Kinase/Fructose-2,6-Biphosphatase 4 (PFKFB4), Pyruvate Kinase (PKM) and Lactate Dehydrogenase A (LDH). Met suppressed the expression of c-Myc, BAX and cyclin-D1 (CCND1) and evoked apoptosis in HTB-35 cells. In conclusion, both small molecules CA and Met are capable of disrupting energy homeostasis, regulating oxidative metabolism/glycolysis in cervical tumor cells in regard to specific metabolic phenotype of the cells. CA and Met may provide a promising approach in the prevention of cervical cancer progression.

Methyl ferulic acid attenuates ethanol-induced hepatic steatosis by regulating AMPK and FoxO1 Pathways in Rats and L-02 cells

Methyl ferulic acid (MFA) is a biologically active monomer extracted and purified from the Chinese herbal medicine Securidaca inappendiculata hasskarl. The previously studies showed that MFA improved acute liver injury induced by ethanol. However, the effect of MFA on ethanol-induced hepatic steatosis in alcoholic liver disease (ALD) still remains unclear. The current study was aimed at elucidating the effect of MFA on alcohol-induced hepatic steatosis and the underlying mechanisms. Human hepatocyte L-02 cells exposed to 200 mM ethanol for 24 h to simulate alcoholic steatosis in vitro. SD rats were fed a Lieber-DeCarli diet containing 5% (w/v) alcohol for 16 weeks to induce alcoholic liver disease in vivo. We examined the effect of MFA on ethanol-induced lipid deposition in L-02 cells and SD rats. The results showed that MFA reduced the accumulation of lipid in L-02 cells, improved alcoholic liver injury in rats, alleviated hepatic pathological lesions, and reduced lipid deposition in rat serum and liver. Further studies suggest that MFA reduces lipid synthesis by activating AMPK-ACC/MAPK-FoxO1 pathway. In addition, MFA also promotes lipid oxidation by up-regulating the expression of SIRT1, PPAR-α, and CPT-1α. Taken together, MFA ameliorates ethanol-induced hepatic steatosis by activating AMPK-ACC/MAPK-FoxO1 pathway and up-regulating the expression levels of SIRT1, PPAR-α, and CPT-1α.

Distribution Analysis of Anthocyanins, Sugars, and Organic Acids in Strawberry Fruits Using Matrix-Assisted Laser Desorption/Ionization-Imaging Mass Spectrometry

Anthocyanins, sugars, and organic acids contribute to the appearance, health benefits, and taste of strawberries. However, their spatial distribution in the ripe fruit has been fully unrevealed. Therefore, we performed matrix-assisted laser desorption/ionization, MALDI-IMS, analysis to investigate their spatial distribution in ripe strawberries. The detection sensitivity was improved by using the TM-Sprayer for matrix application. In the receptacle, pelargonidins were distributed in the skin, cortical, and pith tissues, whereas cyanidins and delphinidins were slightly localized in the skin. In the achene, mainly cyanidins were localized in the outside of the skin. Citric acid was mainly distributed in the upper and bottom side of cortical tissue. Although hexose was distributed almost equally throughout the fruits, sucrose was mainly distributed in the upper side of cortical and pith tissues. These results suggest that using the TM-Sprayer in MALDI-IMS was useful for microscopic distribution analysis of anthocyanins, sugars, and organic acids in strawberries.