Cell suspension culture of Eriobotrya japonica regulates the diabetic and hyperlipidemic signs of high-fat-fed mice

Differences in diacylglycerol acyltransferases expression patterns and regulation cause distinct hepatic triglyceride deposition in fish

Triglyceride (TAG) deposition in the liver is associated with metabolic disorders. In lower vertebrate, the propensity to accumulate hepatic TAG varies widely among fish species. Diacylglycerol acyltransferases (DGAT1 and DGAT2) are major enzymes for TAG synthesis. Here we show that large yellow croaker (Larimichthys crocea) has significantly higher hepatic TAG level than that in rainbow trout (Oncorhynchus mykiss) fed with same diet. Hepatic expression of DGATs genes in croaker is markedly higher compared with trout under physiological condition. Meanwhile, DGAT1 and DGAT2 in both croaker and trout are required for TAG synthesis and lipid droplet formation in vitro. Furthermore, oleic acid treatment increases DGAT1 expression in croaker hepatocytes rather than in trout and has no significant difference in DGAT2 expression in two fish species. Finally, effects of various transcription factors on croaker and trout DGAT1 promoter are studied. We find that DGAT1 is a target gene of the transcription factor CREBH in croaker rather than in trout. Overall, hepatic expression and transcriptional regulation of DGATs display significant species differences between croaker and trout with distinct hepatic triglyceride deposition, which bring new perspectives on the use of fish models for studying hepatic TAG deposition.

Traditional uses, phytochemistry, pharmacology, and toxicity of Eriobotrya japonica leaves: A summary

ETHNOPHARMACOLOGICAL RELEVANCE

Eriobotrya japonica Lindl. has been included in "The Plant List" (http://www.theplantlist.org) and is the most widely researched species in its genus. E. japonica is a subtropical evergreen fruit tree belonging to the Rosaceae family. Its dried leaves are widely used in traditional Chinese herbal medicine to treat coughing caused by pulmonary inflammation, dyspnea due to asthma and cough, nausea caused by stomach disorders, restlessness, and thirst. Furthermore, it is used to treat stomach ache, ulcers, chronic bronchitis, cancer, and diabetes mellitus in Japanese folk medicine. However, no systematic reports on E. japonica leaves have been published before.

AIM OF THE STUDY

This review summarizes the available information on the traditional uses, phytochemistry, pharmacology, toxicity, and quality control of various extracts and phytoconstituents of E. japonica leaves.

MATERIALS AND METHODS

Relevant publications between 1931 and 2022 were considered. Chinese and English studies on E. japonica leaves were collected from databases, including PubMed, Web of Science, Elsevier, ACS Publications, Springer, and CNKI (Chinese). The traditional uses, phytochemistry, pharmacology, toxicity, and quality control of E. japonica leaves were reviewed.

RESULTS

Briefly, 164 compounds, including triterpenes, flavonoids, sesquiterpene glycosides, megastigmane derivatives, phenylpropanoids, and organic acids, have been identified from E. japonica leaves, in addition to 169 volatile oils. More than half of these compounds have not yet been reported to have pharmacological activities. Triterpenes and flavonoids are the most important bioactive compounds responsible for pharmacological activities, such as antidiabetic, anti-inflammatory, and antitumor activities. Other beneficial physiological effects such as antioxidant, hepatoprotective, bronchodilatory, antitussive, and expectorant effects and tracheal smooth muscle relaxation, protection against myocardial ischemia injury, and improved cognitive activities have also been reported. High doses of E. japonica leaf extracts have been used in laboratory animals, and no side effects or toxicity-symptoms have been observed.

CONCLUSIONS

The pharmacological activities of E. japonica leaves support their use in traditional Chinese herbal medicine. However, several aspects, such as the bioavailability, pharmacodynamics, pharmacokinetics, mechanism of action, and structure-activity relationships of the pure compounds isolated from E. japonica leaves, have not been studied yet and warrant further studies.

Natural Compounds for Counteracting Nonalcoholic Fatty Liver Disease (NAFLD): Advantages and Limitations of the Suggested Candidates

The booming prevalence of nonalcoholic fatty liver disease (NAFLD) in adults and children will threaten the health system in the upcoming years. The "multiple hit" hypothesis is the currently accepted explanation of the complex etiology and pathophysiology of the disease. Some of the critical pathological events associated with the development of NAFLD are insulin resistance, steatosis, oxidative stress, inflammation, and fibrosis. Hence, attenuating these events may help prevent or delay the progression of NAFLD. Despite an increasing understanding of the mechanisms involved in NAFLD, no approved standard pharmacological treatment is available. The only currently recommended alternative relies on lifestyle modifications, including diet and physical activity. However, the lack of compliance is still hampering this approach. Thus, there is an evident need to characterize new therapeutic alternatives. Studies of food bioactive compounds became an attractive approach to overcome the reticence toward lifestyle changes. The present study aimed to review some of the reported compounds with beneficial properties in NAFLD; namely, coffee (and its components), tormentic acid, verbascoside, and silymarin. We provide details about their protective effects, their mechanism of action in ameliorating the critical pathological events involved in NAFLD, and their clinical applications.

Cell suspension culture extract of Eriobotrya japonica attenuates growth and induces apoptosis in prostate cancer cells via targeting SREBP-1/FASN-driven metabolism and AR

BACKGROUND

Castration-resistant prostate cancer (CRPC) is one of the main causes of male cancer mortality. There is currently no effective treatment to cure this deadly prostate cancer (PCa) progression. However, recent research showed that activation of lipogenesis leads to CRPC progression. It provides a rationale to target the highly lipogenic activity as a novel and promising therapy against lethal CRPC.

PURPOSES

The present study aims to evaluate the anticancer efficacy and the molecular mechanism of cell suspension culture extract from Eriobotrya japonica (EJCE) in PCa, including CRPC.

METHODS

Cell growth, migration and invasion analyses were performed by MTT method, a wound healing assay and the transwell method, respectively. Apoptosis was assessed by a flow cytometry-based Annexin V-FITC/PI assay, caspase enzymatic activity and Western blot analyses. Lipogenesis was determined by a Fatty Acid Quantification Kit and an Oil Red O staining. The in vivo experiment was conducted by a xenograft mouse model.

RESULTS

PCa cell growth, migration and invasion were significantly affected by EJCE. EJCE decreased expression of sterol regulatory element-binding protein-1 (SREBP-1) and fatty acid synthase (FASN) in PCa cells, two main factors for lipogenesis. By inhibiting SREBP-1/FASN, EJCE reduced the intracellular fatty acid levels and lipid droplet accumulation in PCa. Moreover, EJCE down-regulated the androgen receptor (AR) and prostate-specific antigen (PSA) in PCa cells. Significantly, EJCE exhibited the potential anticancer activity by suppressing the growth and leading to apoptosis of CRPC tumors in a xenograft mouse model.

CONCLUSION

These results reveal a novel therapeutic molecular mechanism of EJCE in PCa. Blockade of SREBP-1/FASN-driven metabolism and AR by EJCE could be employed as a potent opportunity to cure malignant PCa.

Total Sesquiterpene Glycosides from Loquat Leaves Ameliorate HFD-Induced Insulin Resistance by Modulating IRS-1/GLUT4, TRPV1, and SIRT6/Nrf2 Signaling Pathways

Loquat (Eriobotrya japonica Lindl.), a subtropical fruit tree native to Asia, is not only known to be nutritive but also beneficial for the treatment of diabetes in the south of China. To expand its development, this study was undertaken concerning the potential therapeutic role of total sesquiterpene glycosides (TSGs) from loquat leaves in insulin resistance (IR), the major causative factor of type 2 diabetes mellitus (T2DM). Male C57BL/6 mice were fed on high-fat diet (HFD) to induce IR and then were given TSG by oral administration at 25 and 100 mg/kg/day, respectively. TSG notably improved metabolic parameters including body weight, serum glucose, and insulin levels and prevented hepatic injury. Moreover, inflammatory response and oxidative stress were found to be remarkably alleviated in IR mice with TSG supplement. Further research in liver of IR mice demonstrated that TSG repaired the signalings of insulin receptor substrate-1 (IRS-1)/glucose transporter member 4 (GLUT4) and AMP-activated protein kinase (AMPK), which improved glucose and lipid metabolism and prevented lipid accumulation in liver. It was also observed that TSG suppressed the expression of transient receptor potential vanilloid 1 (TRPV1), whereas the signaling pathway of sirtuin-6 (SIRT6)/nuclear factor erythroid 2-related factor 2 (Nrf2) was significantly promoted. Based on the results, the current study demonstrated that TSG from loquat leaves potentially ameliorated IR in vivo by enhancing IRS-1/GLUT4 signaling and AMPK activation and modulating TRPV1 and SIRT6/Nrf2 signaling pathways.

The Occurrence and Biological Activity of Tormentic Acid-A Review

This review focuses on the natural sources and pharmacological activity of tormentic acid (TA; 2α,3β,19α-trihydroxyurs-2-en-28-oic acid). The current knowledge of its occurrence in various plant species and families is summarized. Biological activity (e.g., anti-inflammatory, antidiabetic, antihyperlipidemic, hepatoprotective, cardioprotective, neuroprotective, anti-cancer, anti-osteoarthritic, antinociceptive, antioxidative, anti-melanogenic, cytotoxic, antimicrobial, and antiparasitic) confirmed in in vitro and in vivo studies is compiled and described. Biochemical mechanisms affected by TA are indicated. Moreover, issues related to the biotechnological methods of production, effective eluents, and TA derivatives are presented.

Progress in the discovery of naturally occurring anti-diabetic drugs and in the identification of their molecular targets

Diabetes mellitus (DM), a chronic metabolic disease, severely affects patients' life and intensively increases risks of developing other diseases. It is estimated that 0.4 billion individuals worldwide are subjected to diabetes, especially type 2 diabetes mellitus. At present, although various synthetic drugs for diabetes such as Alogliptin and Rosiglitazone, etc. have been used to manage diabetes, some of them showed severe side effects. Given that the pathogenesis of type 2 diabetes mellitus, natural occurring drugs are beneficial alternatives for diabetes therapy with low adverse effects or toxicity. Recently, more and more plant-derived extracts or compounds were evaluated to have anti-diabetic activities. Their anti-diabetic mechanisms involve certain key targets like α-glucosidase, α-amylase, DPP-4, PPAR γ, PTP1B, and GLUT4, etc. Here, we summarize the newly found anti-diabetic (type 2 diabetes mellitus) natural compounds and extracts from 2011-2017, and give the identification of their molecular targets. This review could provide references for the research of natural agents curing type 2 diabetes mellitus (T2DM).

n-Butanol Extract of Lotus Seeds Exerts Antiobesity Effects in 3T3-L1 Preadipocytes and High-Fat Diet-Fed Mice via Activating Adenosine Monophosphate-Activated Protein Kinase

In this study, the antiobesity effects of n-butanol extract of lotus seeds (LBE) were evaluated in cultured 3T3-L1 preadipocytes and in high-fat diet (HFD)-fed mice. LBE decreased lipid contents in mature 3T3-L1 cells without obvious cytotoxicity. Meanwhile, LBE supplementation also led to weight loss and improved plasma lipid profiles in HFD-fed mice. Furthermore, LBE could activate AMP-activated protein kinase (AMPK) accompanied by down-regulation of lipogenesis related genes (PPARγ, aP2, LPL, C/EBPα, FAS, SREBP-1c) and up-regulation of lipolysis genes (adiponectin and PPARα) in vitro and in vivo. Collectively, our data demonstrated LBE possesses antiadipogenic and antilipogenic activities which are, at least partially, mediated by the activation of AMPK signaling pathways.

Eriobotrya japonica ameliorates cardiac hypertrophy in H9c2 cardiomyoblast and in spontaneously hypertensive rats

Eriobotrya japonica (EJ) is a traditional Chinese plant with high medicinal value. EJ extracts are reported to exhibit antioxidant and anti-inflammatory biological attributes. The current study aims to evaluate the prospective efficacy of E. japonica leave extract (EJLE) against Angiotensin-II induced cardiac hypertrophy in H9c2 cardiomyoblast and in spontaneously hypertensive rats (SHRs). For the in vitro studies, Angiotensin-II pretreated H9c2 cells were treated with EJLE and analyzed through Western blotting and rhodamine phalloidin staining for their cardio-protective attributes. In the in vivo studies, 12-week-old SHRs were randomly divided into groups: SHRs supplemented with EJLE, control SHR group supplemented with PBS; in addition, a control group of Wistar-Kyoto rats (WKY) was also employed. All rats were supplemented twice a week for 8 week time interval. Finally, echocardiography, morphological, histology, and Western blot analysis were performed to assess their role against cardiac hypertrophy. Interestingly, we could observe that supplementation of EJLE could rescue Ang-II induced cardiac hypertrophy as evident through Western blot, rhodamine phalloidin staining, and Hematoxylin-Eosin staining. Notably, morphological and echocardiography data provided further supports for their ability to ameliorate cardiac characteristics. Cumulatively, the results clearly suggests that supplementation of EJLE promotes cardio-protective effects through amelioration of cardiac hypertrophy in vitro and in vivo.

Hepatoprotective Effect of Loquat Leaf Flavonoids in PM2.5-Induced Non-Alcoholic Fatty Liver Disease via Regulation of IRs-1/Akt and CYP2E1/JNK Pathways

Ambient air particulate matter (PM) represents a class of heterogeneous substances present in polluted air, which contains many harmful components. Exposure to ambient particulate matter in fine rages (PM_2.5) is associated with non-alcoholic fatty liver disease (NAFLD). Loquat Leaf possesses pharmacological actions on NAFLD. As the main biological active ingredients, the potential therapeutic role of total flavonoids (TF) isolated from Loquat Leaf in PM_2.5-induced NAFLD model remains unclear. The present study was designed to explore the hepatoprotective effect of TF in PM_2.5-induced NAFLD mice with its related mechanisms of action. Mice were exposed to PM_2.5 to induce NAFLD, and body weight, the ratio of liver to body weight, and blood lipids increased significantly compared with the control group. It was found that TF significantly reduced the above parameters in PM_2.5-induced NAFLD mice. TF treatment alleviated oxidative stress by preventing the accumulation of oxidative product malondialdehyde (MDA) and by strengthening the anti-oxidative capacity of superoxide dismutase (SOD). TF was also found to reduce the alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activity in the PM_2.5 group. In addition, TF repaired the PM_2.5-induced decline of insulin receptor substrate-1 (IRs-1) and protein kinase B (Akt) phosphorylation. Meanwhile, the data showed TF suppressed the expression of cytochrome P450 2E1(CYP2E1) and the phosphorylation of c-jun N-terminal kinase (JNK) in PM_2.5-induced NAFLD. Taken together, these findings show that TF alleviate PM_2.5-induced NAFLD via regulation of IRs-1/Akt and CYP2E1/JNK pathways, which may have potential for further development as novel therapeutic agents for NAFLD.

A novel sesquiterpene glycoside from Loquat leaf alleviates oleic acid-induced steatosis and oxidative stress in HepG2 cells

Loquat (Eriobotrya japonica) leaf has displayed beneficial effect on metabolic syndrome. In our previously study, total sesquiterpene glycosides (TSG) isolated from Loquat leaf exhibited therapeutic effect on Non-alcoholic fatty liver disease (NAFLD) in vivo, but the accurate active compound remains unknown. Sesquiterpene glycoside 1 (SG1) is a novel compound, which is exclusively isolated from Loquat leaf, but its biological activity has been rarely reported. The present study was designed to evaluate the pharmacological effect of SG1, the main component of TSG, in oleic acid (OA)-induced HepG2 cell model of NAFLD with its related mechanisms of action. In this study, both SG1 and TSG were found to significantly reduce the lipid deposition in the cell model. They could also decrease total cholesterol (TC), triglyceride (TG) and intracellular free fatty acid (FFA) contents. Compared with OA-treated cells, the superoxide dismutase (SOD) level increased, and the malondialdehyde (MDA) and 4-hydroxynonenal levels respectively decreased after the administration of SG1 or TSG. The high dose of SG1 (140 μg/mL) displayed a similar therapeutic effect as TSG at 200 μg/mL. Both SG1 and TSG were found to suppress the expression of cytochrome P450 2E1 (CYP2E1) and the phosphorylation of c-jun terminal kinase (JNK) and its downstream target c-Jun in OA-treated cell. These results demonstrate again that TSG are probably the main responsible chemical profiles of Loquat leaf for the treatment of NAFLD, for which it can effectively improve OA-induced steatosis and reduce oxidative stress, probably by downregulating of CYP2E1 expression and JNK/c-Jun phosphorylation, while SG1 may be the principle compound.

Syringaresinol-4-O-β-d-glucoside alters lipid and glucose metabolism in HepG2 cells and C2C12 myotubes

Syringaresinol-4-O-β-d-glucoside (SSG), a furofuran-type lignan, was found to modulate lipid and glucose metabolism through an activity screen of lipid accumulation and glucose consumption, and was therefore considered as a promising candidate for the prevention and treatment of metabolic disorder, especially in lipid and glucose metabolic homeostasis. In this study, the effects of SSG on lipogenesis and glucose consumption in HepG2 cells and C2C12 myotubes were further investigated. Treatment with SSG significantly inhibited lipid accumulation by oil red O staining and reduced the intracellular contents of total lipid, cholesterol and triglyceride in HepG2 cells. No effect was observed on cell viability in the MTT assay at concentrations of 0.1–10 μmol/L. SSG also increased glucose consumption by HepG2 cells and glucose uptake by C2C12 myotubes. Furthermore, real-time quantitative PCR revealed that the beneficial effects were associated with the down-regulation of sterol regulatory element-binding proteins-1c, -2 (SREBP-1c, -2), fatty acid synthase (FAS), acetyl CoA carboxylase (ACC) and hydroxyl methylglutaryl CoA reductase (HMGR), and up-regulation of peroxisome proliferator-activated receptors alpha and gamma (PPARα and PPARγ). SSG also significantly elevated transcription activity of PPARγ tested by luciferase assay. These results suggest that SSG is an effective regulator of lipogenesis and glucose consumption and might be a candidate for further research in the prevention and treatment of lipid and glucose metabolic diseases.

Protective Effects of Tormentic Acid, a Major Component of Suspension Cultures of Eriobotrya japonica Cells, on Acetaminophen-Induced Hepatotoxicity in Mice

An acetaminophen (APAP) overdose can cause hepatotoxicity and lead to fatal liver damage. The hepatoprotective effects of tormentic acid (TA) on acetaminophen (APAP)-induced liver damage were investigated in mice. TA was intraperitoneally (i.p.) administered for six days prior to APAP administration. Pretreatment with TA prevented the elevation of serum aspartate aminotransferase (AST), alanine aminotransferase (ALT), total bilirubin (T-Bil), total cholesterol (TC), triacylglycerol (TG), and liver lipid peroxide levels in APAP-treated mice and markedly reduced APAP-induced histological alterations in liver tissues. Additionally, TA attenuated the APAP-induced production of nitric oxide (NO), reactive oxygen species (ROS), tumor necrosis factor-alpha (TNF-α), interleukin-1beta (IL-1β), and IL-6. Furthermore, the Western blot analysis showed that TA blocked the protein expression of inducible NO synthase (iNOS) and cyclooxygenase-2 (COX-2), as well as the inhibition of nuclear factor-kappa B (NF-κB) and mitogen-activated protein kinases (MAPKs) activation in APAP-injured liver tissues. TA also retained the superoxidase dismutase (SOD), glutathione peroxidase (GPx), and catalase (CAT) in the liver. These results suggest that the hepatoprotective effects of TA may be related to its anti-inflammatory effect by decreasing thiobarbituric acid reactive substances (TBARS), iNOS, COX-2, TNF-α, IL-1β, and IL-6, and inhibiting NF-κB and MAPK activation. Antioxidative properties were also observed, as shown by heme oxygenase-1 (HO-1) induction in the liver, and decreases in lipid peroxides and ROS. Therefore, TA may be a potential therapeutic candidate for the prevention of APAP-induced liver injury by inhibiting oxidative stress and inflammation.

Total sesquiterpene glycosides from Loquat (Eriobotrya japonica) leaf alleviate high-fat diet induced non-alcoholic fatty liver disease through cytochrome P450 2E1 inhibition

Non-alcoholic fatty liver disease (NAFLD) is a chronic liver disease characterized by hepatic steatosis, which affects 20-40% of the population in the world. Loquat (Eriobotrya japonica) Leaf possesses several pharmacological actions. Many sesquiterpene glycosides were reported to be isolated exclusively from the Loquat Leaf, however, their biological activity has been rarely investigated. The present study was designed to evaluate the pharmacological effect of total sesquiterpene glycosides (TSG) in high-fat diet (HFD) induced NAFLD mice with its related mechanisms of action. Mice were fed with a normal diet or HFD for 8 weeks. TSG (25 and 100mg/kg/day), simvastatin (10mg/kg/day) or vehicle were orally administered for last 4 weeks of the 8-week HFD feeding period. From the result, it was showed that TSG significantly reduced the body weight and fat deposition in the liver of NAFLD mice. It also decreased total cholesterol (TC) and triglyceride (TG) contents in the serum. Compared with NAFLD mice, superoxide dismutase (SOD) and malondialdehyde (MDA) levels were increased and decreased after the administration of TSG in a dose of 100mg/kg, respectively. TSG reduced alanine aminotransferase (ALT) activity as well. Finally, TSG was found to suppress the expression of cytochrome P450 2E1 (CYP2E1) and the phosphorylation of c-jun terminal kinase (JNK) in NAFLD mice. In summary, this study demonstrates that TSG reduces oxidative stress by downregulating of CYP2E1 expression and JNK phosphorylation in NAFLD, and alleviates NAFLD ultimately. TSG potentially serves as bioactive compounds for the treatment of NAFLD.

Biological Activities of Extracts from Loquat (Eriobotrya japonica Lindl.): A Review

Loquat (Eriobotrya japonica Lindl.) is a subtropical fruit tree with high medicinal value native to China. Different organs of loquat have been used historically as folk medicines and this has been recorded in Chinese history for thousands of years. Research shows that loquat extracts contain many antioxidants, and different extracts exhibit bioactivity capable of counteracting inflammation, diabetes, cancer, bacterial infection, aging, pain, allergy and other health issues. Bioactive compounds such as phenolics and terpenoids have been isolated and characterized to provide a better understanding of the chemical mechanisms underlying the biological activities of loquat extracts. As the identification of compounds progresses, studies investigating the in vivo metabolism, bioavailability, and structure–activity relationships, as well as potential toxicity of loquat extracts in animal or cell models are receiving more attention. In addition, genetic studies and breeding of loquat germplasms for high contents of health-benefiting compounds may provide new insight for the loquat industry and research. This review is focused on the main medicinal properties reported and the possible pharmaceutically active compounds identified in different loquat extracts.

Antcin K, a Triterpenoid Compound from Antrodia camphorata, Displays Antidiabetic and Antihyperlipidemic Effects via Glucose Transporter 4 and AMP-Activated Protein Kinase Phosphorylation in Muscles

The purpose of this study was to screen firstly the potential effects of antcin K (AnK), the main constituent of the fruiting body of Antrodia camphorata, in vitro and further evaluate the activities and mechanisms in high-fat-diet- (HFD-) induced mice. Following 8-week HFD-induction, mice were treated with AnK, fenofibrate (Feno), metformin (Metf), or vehicle for 4 weeks afterward. In C2C12 myotube cells, the membrane GLUT4 and phospho-Akt expressions were higher in insulin and AnK-treated groups than in the control group. It was observed that AnK-treated mice significantly lowered blood glucose, triglyceride, total cholesterol, and leptin levels in AnK-treated groups. Of interest, AnK at 40 mg/kg/day dosage displayed both antihyperglycemic effect comparable to Metf (300 mg/kg/day) and antihypertriglyceridemic effect comparable to Feno (250 mg/kg/day). The combination of significantly increased skeletal muscular membrane expression levels of glucose transporter 4 (GLUT4) but decreased hepatic glucose-6-phosphatase (G6 Pase) mRNA levels by AnK thus contributed to a decrease in blood glucose levels. Furthermore, AnK enhanced phosphorylation of AMP-activated protein kinase (phospho-AMPK) expressions in the muscle and liver. Moreover, AnK treatment exhibited inhibition of hepatic fatty acid synthase (FAS) but enhancement of fatty acid oxidation peroxisome proliferator-activated receptor α (PPARα) expression coincident with reduced sterol response element binding protein-1c (SREBP-1c) mRNA levels in the liver may contribute to decreased plasma triglycerides, hepatic steatosis, and total cholesterol levels. The present findings indicate that AnK displays an advantageous therapeutic potential for the management of type 2 diabetes and hyperlipidemia.

The potential beneficial effects of phenolic compounds isolated from A. pilosa Ledeb on insulin-resistant hepatic HepG2 cells

Agrimonia pilosaLedeb (AP) has already been applied in practice for the treatment of different disorders and is available to access without the provision of a medical prescription.

Antidiabetic and Antihyperlipidemic Properties of a Triterpenoid Compound, Dehydroeburicoic Acid, from Antrodia camphorata in Vitro and in Streptozotocin-Induced Mice

The aim of this study was to examine the effects of dehydroeburicoic acid (TT) on type 1 diabetes mellitus and dyslipidemia in streptozotocin (STZ)-induced diabetic mice. STZ-induced diabetic mice were randomly divided into six groups and given orally by gavage TT (at three dosages), metformin (Metf), fenfibrate (Feno), or vehicle for 4 weeks. STZ-induced diabetic mice showed elevations in blood glucose levels (P < 0.001). TT treatment markedly decreased blood glucose levels by 42.6-46.5%. Moreover, STZ-induced diabetic mice displayed an increase in circulating triglyceride (TG) and total cholesterol (TC) levels (P < 0.001 and P < 0.01, respectively) but a decrease in blood insulin and adiponectin levels (P < 0.01 and P < 0.05, respectively). These substances are also reversed by TT treatment, indicating TT ameliorated diabetes and dyslipidemia. Membrane skeletal muscular expression levels of glucose transporter 4 (GLUT4) and expression levels of AMPK phosphorylation (phospho-AMPK) in both liver and skeletal muscle were reduced in STZ-induced diabetic mice, which normalized upon TT treatment and correction of hyperglycemia accompanied with a decrease in mRNA levels of phosphoenolpyruvate carboxykinase (PEPCK) and glucose-6-phosphatase (G6 Pase), which was related to the inhibition of hepatic glucose production and attenuating diabetic state. In addition, TT also showed hypolipidemic effect by increasing hepatic expression levels of peroxisome proliferator-activated receptor α (PPARα) and mRNA levels of carnitine palmitoyl transferase Ia (CPT-1a) but decreasing expression levels of fatty acid synthase (FAS), which further contributed to a decrease in circulating TG levels. TT-treated mice displayed decreased SREBP2 mRNA levels and reduced blood TC levels. These findings strongly support that TT prevents diabetic and dyslipidemic states in STZ-induced diabetic mice evidenced by regulation of GLUT4, PPARα, FAS, and phosphorylation of AMPK.

(-)-Epicatechin-3-O-β-D-allopyranoside from Davallia formosana, Prevents Diabetes and Hyperlipidemia by Regulation of Glucose Transporter 4 and AMP-Activated Protein Kinase Phosphorylation in High-Fat-Fed Mice

The purpose of this experiment was to determine the antidiabetic and lipid-lowering effects of (−)-epicatechin-3-O-β-d-allopyranoside (BB) from the roots and stems of Davallia formosana in mice. Animal treatment was induced by high-fat diet (HFD) or low-fat diet (control diet, CD). After eight weeks of HFD or CD exposure, the HFD mice were treating with BB or rosiglitazone (Rosi) or fenofibrate (Feno) or water through gavage for another four weeks. However, at 12 weeks, the HFD-fed group had enhanced blood levels of glucose, triglyceride (TG), and insulin. BB treatment significantly decreased blood glucose, TG, and insulin levels. Moreover, visceral fat weights were enhanced in HFD-fed mice, accompanied by increased blood leptin concentrations and decreased adiponectin levels, which were reversed by treatment with BB. Muscular membrane protein levels of glucose transporter 4 (GLUT4) were reduced in HFD-fed mice and significantly enhanced upon administration of BB, Rosi, and Feno. Moreover, BB treatment markedly increased hepatic and skeletal muscular expression levels of phosphorylation of AMP-activated (adenosine monophosphate) protein kinase (phospho-AMPK). BB also decreased hepatic mRNA levels of phosphenolpyruvate carboxykinase (PEPCK), which are associated with a decrease in hepatic glucose production. BB-exerted hypotriglyceridemic activity may be partly associated with increased mRNA levels of peroxisome proliferator activated receptor α (PPARα), and with reduced hepatic glycerol-3-phosphate acyltransferase (GPAT) mRNA levels in the liver, which decreased triacylglycerol synthesis. Nevertheless, we demonstrated BB was a useful approach for the management of type 2 diabetes and dyslipidemia in this animal model.

Ergostatrien-3β-ol from Antrodia camphorata inhibits diabetes and hyperlipidemia in high-fat-diet treated mice via regulation of hepatic related genes, glucose transporter 4, and AMP-activated protein kinase phosphorylation

This study was designed to explore the effects and mechanism of ergostatrien-3β-ol (EK100) from the submerged whole broth of Antrodia camphorata on diabetes and dyslipidemia in high fat diet (HFD)-fed mice for 12 weeks. The C57BL/6J mouse fed with a high fat diet (HFD) could induce insulin resistance and hyperlipidemia. After 8 week of induction, mice were receiving EK100 (at three dosages) or fenofibrate (Feno) or rosiglitazone (Rosi) or vehicle by oral gavage 4 weeks afterward. HFD-fed mice display increased blood glucose, glycated hemoglobin (HbA1c), total cholesterol (TC), triglyceride (TG), insulin, and leptin levels. These blood markers were significantly lower in EK100-treated mice, and finally ameliorated insulin resistance. EK100 treatment exhibited reduced hepatic ballooning degeneration and size of visceral adipocytes. Glucose transporter 4 (GLUT4) proteins and phosphorylation of Akt in skeletal muscle were significantly increased in EK100- and Rosi-treated mice. EK100, Feno, and Rosi treatment led to significant increases in phosphorylation of AMP-activated protein kinase (phospho-AMPK) protein in both skeletal muscle and liver. Moreover, EK100 caused a decrease in hepatic expressions of phosphenolpyruvate carboxykinase (PEPCK) and glucose-6-phosphatase (G6 Pase), and decreased glucose production. EK100 lowered blood TG level by inhibition of hepatic fatty acid synthesis by dampening sterol response element binding protein-1c (SREBP-1c) but increasing expression of peroxisome proliferator activated receptor α (PPARα). Moreover, EK100-treated mice reduced blood TC levels by decreased hepatic expressions of SREBP2, which plays a major role in the regulation of cholesterol synthesis. EK100 increased high-density lipoprotein cholesterol (HDL-C) concentrations by increasing expressions of apolipoprotein A-I (apo A-I) in liver tissue. Our findings manifest that EK100 may have therapeutic potential in treating type 2 diabetes associated with hyperlipidemia in HFD-fed mice by regulation of GLUT4, PEPCK, G6 Pase, SREBP1c, SREBP2, apo A-I, and AMPK phosphorylation.

Tormentic acid, a major component of suspension cells of Eriobotrya japonica, suppresses high-fat diet-induced diabetes and hyperlipidemia by glucose transporter 4 and AMP-activated protein kinase phosphorylation

This study was designed to evaluate the effects and mechanism of tormentic acid (PTA) on diabetes and dyslipidemia in high-fat (HF)-fed mice. Feeding C57BL/6J mice with a HF diet for 12 weeks induced type 2 diabetes and hyperlipidemia. During the last 4 weeks, the mice were given orally PTA (at two dosages) or rosiglitazone (Rosi) or water. In this study, the HF diet increased glucose, triglyceride, insulin, and leptin levels, whereas PTA effectively prevented these phenomena and ameliorated insulin resistance. PTA reduced visceral fat mass and hepatic triacylglycerol contents; moreover, PTA significantly decreased both the area of adipocytes and ballooning degeneration of hepatocytes. PTA caused increased skeletal muscular AMP-activated protein kinase (AMPK) phosphorylation and Akt phosphorylation and glucose transporter 4 (GLUT4) proteins, but reduced the hepatic expressions of phosphenolpyruvate carboxykinase (PEPCK) and glucose-6-phosphatase (G6 Pase) genes. PTA enhanced skeletal muscular Akt phosphorylation and increased insulin sensitivity. PTA also enhanced phospho-AMPK in the liver. Therefore, it is possible that the activation of AMPK by PTA results in decreasing hepatic glucose production while increasing skeletal muscular GLUT4 contents, thus contributing to attenuating the diabetic state. Moreover, PTA exhibits an antihyperlipidemic effect by down-regulations of the hepatic sterol regulatory element binding protein-1c (SREBP-1c) and apolipoprotein C-III (apo C-III) and an increased peroxisome proliferator activated receptor (PPAR)-α expression, thus resulting in decreases in blood triglycerides. These findings demonstrated that PTA was effective for the treatment of diabetes and hyperlipidemia in HF-fed mice.

Effects of Bofu-Tsusho-San on diabetes and hyperlipidemia associated with AMP-activated protein kinase and glucose transporter 4 in high-fat-fed mice

This study was undertaken to examine the effect and mechanism of Bofu-tsusho-san formula (BO) on hyperglycemia and hyperlipidemia and in mice fed with a high-fat (HF) diet. The C57BL/6J mice were received control/HF diet for 12 weeks, and oral administration of BO (at three doses) or rosiglitazone (Rosi) or vehicle for the last 4 weeks. Blood, skeletal muscle and tissues were examined by means of measuring glycaemia and dyslipidaemia-associated events. BO treatment effectively prevented HF diet-induced increases in the levels of triglyceride (TG), free fatty acid (FFA) and leptin (p<0.01, p<0.01, p<0.01, respectively). BO treatment exhibited reduced both visceral fat mass and hepatic triacylglycerol content; moreover, BO treatment displayed significantly decreased both the average area of the cut of adipocytes and ballooning of hepatocytes. BO treatment exerted increased the protein contents of glucose transporter 4 (GLUT4) in skeletal muscle, and caused lowered blood glucose levels. BO treatment displayed increased levels of phosphorylated AMP-activated protein kinase (AMPK) in both skeletal muscle and liver tissue. Furthermore, BO reduced the hepatic expression of glucose-6-phosphatase (G6Pase) and phosphenolpyruvate carboxykinase (PEPCK) and glucose production. Therefore, it is possible that the activation of AMPK by BO leads to diminished gluconeogenesis in liver tissue. BO increased hepatic expressions of peroxisome proliferator-activated receptor α (PPARα), whereas down-regulating decreasing expressions of fatty acid synthesis, including sterol regulatory element binding protein 1c (SREBP1c) and fatty acid synthase (FAS), resulting in a decrease in circulating triglycerides. This study originally provides the evidence that amelioration of dyslipidemic and diabetic state by BO in HF-fed mice occurred by regulation of GLUT4, SREBP1c, FAS, PPARα, adiponectin and AMPK phosphorylation.

Modulation of lipogenesis and glucose consumption in HepG2 cells and C2C12 myotubes by sophoricoside

Sophoricoside, an isoflavone glycoside isolated from Sophora japonica (Leguminosae), has been widely reported as an immunomodulator. In this study, the effects of sophoricoside on lipogenesis and glucose consumption in HepG2 cells and C2C12 myotubes were investigated. Treatment with sophoricoside at concentrations of 1-10 μM inhibited lipid accumulation in HepG2 cells in a dose-dependent manner. At the same concentration range, no effect on cell viability was observed in the MTT assay. Inhibition of lipogenesis was associated with the downregulation of SREBP-1a, SREBP-1c, SREBP-2 and their downstream target genes (FAS, ACC, HMGR) as revealed by realtime quantitative PCR. The lipid-lowering effect was mediated via the phosphorylation of AMPK. Further investigation of the activities of this isoflavone showed that sophoricoside has the capability to increase glucose uptake by C2C12 myotubes. It also effectively inhibited the activities of α-glucosidase and α-amylase in vitro and remarkably lowered postprandial hyperglycaemia in starch-loaded C57BL6/J mice. These results suggest that sophoricoside is an effective regulator of lipogenesis and glucose consumption and may find utility in the treatment of obesity and type 2 diabetes.