Phenylethanoid glycosides extract from Cistanche deserticola ameliorates atherosclerosis in apolipoprotein E-deficient mice and regulates intestinal PPARγ-LXRα-ABCA1 pathway.

OBJECTIVES: This study was aimed to evaluate the protective effects of phenylethanoid glycosides extract from Cistanche deserticola against atherosclerosis and its molecular mechanism. METHODS: Total phenylethanoid glycosides were extracted and purified from C. deserticola, and the C. deserticola extract (CDE) was used to treat a mice model of atherosclerosis. KEY FINDINGS: CDE containing 81.00% total phenylethanoid glycosides, with the contents of echinacoside and acteoside being 31.36% and 7.23%, respectively. A 13-week of CDE supplementation (1000 mg/kg body weight/day) significantly reduced atherosclerotic lesions in the aortic sinus and entire aorta in ApoE-/- mice fed with a high-fat diet. In addition, varying doses of CDE (250, 500 and 1000 mg/kg body weight/day) lowered plasma total cholesterol, triglyceride and non-high-density lipoprotein cholesterol levels. Transcriptomic analysis of the small intestine revealed the changes enriched in cholesterol metabolic pathway and the activation of Abca1 gene. Further validation using real-time quantitative PCR and western blot confirmed that CDE significantly increased the mRNA levels and protein expressions of ABCA1, LXRα and PPARγ. CONCLUSIONS: Our results demonstrate the beneficial effects of C. deserticola on atherosclerotic plaques and lipid homeostasis, and it is, at least partially, by activating PPARγ-LXRα-ABCA1 pathway in small intestine.

Arctium lappa leaves based on network pharmacology and experimental validation attenuate atherosclerosis by targeting the AMPK-mediated PPARG/LXRα pathway.

Arctium lappa (A. lappa) leaves are widely used in various traditional Chinese herbal formulae to ameliorate atherosclerosis (AS) and its complications such as stroke; however, there is no literature reporting the anti-atherosclerotic effect and mechanism of A. lappa leaves thus far. In the present study, we used network pharmacology and molecular docking approaches to examine the protective effect and potential mechanism of A. lappa leaves against AS in vivo and in vitro. From the network pharmacology, PPARG, HMGCR and SREBF2 were identified as the core targets of A. lappa leaves against AS. Further enrichment analyses of GO and KEGG pathways suggested that A. lappa leaves might play an anti-AS role by regulating metabolic processes and PPAR signalling pathways. The results of molecular docking experiment revealed that the major components of A. lappa leaves interacted with cholesterol efflux-regulating core proteins (PPARG, LXRα, ABCA1, and ABCG1), AMPK and SIRT1. Both in vivo and in vitro experimental results demonstrated that treatment with A. lappa leaves significantly lowered TC and LDL-C, increased HDL-C, and reduced cholesterol accumulation in the liver and aorta of the AS rat model and the foam cell model. Importantly, both in vivo and in vitro experimental results demonstrated that A. lappa leaves regulate the activity of the PPARG/LXRα signalling and AMPK/SIRT1 signalling pathways. Moreover, after treatment with the AMPK inhibitor Compound C in vitro, the improvement induced by A. lappa leaves was significantly reversed. In conclusion, A. lappa leaves attenuated AS-induced cholesterol accumulation by targeting the AMPK-mediated PPARG/LXRα pathway and promoting cholesterol efflux.

Saikosaponin A and D Inhibit Adipogenesis via the AMPK and MAPK Signaling Pathways in 3T3-L1 Adipocytes.

Obesity is a lipid metabolism disorder caused by genetic, medicinal, nutritional, and other environmental factors. It is characterized by a complex condition of excess lipid accumulation in adipocytes. Adipogenesis is a differentiation process that converts preadipocytes into mature adipocytes and contributes to excessive fat deposition. Saikosaponin A (SSA) and saikosaponin D (SSD) are triterpenoid saponins separated from the root of the Bupleurum chinensis, which has long been used to treat inflammation, fever, and liver diseases. However, the effects of these constituents on lipid accumulation and obesity are poorly understood. We investigated the anti-obesity effects of SSA and SSD in mouse 3T3-L1 adipocytes. The MTT assay was performed to measure cell viability, and Oil Red O staining was conducted to determine lipid accumulation. Various adipogenic transcription factors were evaluated at the protein and mRNA levels by Western blot assay and quantitative reverse transcription polymerase chain reaction (qRT-PCR). Here, we showed that SSA and SSD significantly inhibited lipid accumulation without affecting cell viability within the range of the tested concentrations (0.938-15 µM). SSA and SSD also dose-dependently suppressed the expression of peroxisome proliferator-activated receptor gamma (PPARγ), CCAAT/enhancer binding protein alpha (C/EBPα), sterol regulatory element binding protein-1c (SREBP-1c), and adiponectin. Furthermore, the decrease of these transcriptional factors resulted in the repressed expression of several lipogenic genes including fatty acid binding protein (FABP4), fatty acid synthase (FAS), and lipoprotein lipase (LPL). In addition, SSA and SSD enhanced the phosphorylation of adenosine monophosphate-activated protein kinase (AMPK) and its substrate, acetyl-CoA carboxylase (ACC), and inhibited the phosphorylation of extracellular-regulated kinase 1/2 (ERK1/2) and p38, but not c-Jun-N-terminal kinase (JNK). These results suggest that SSA and SSD inhibit adipogenesis through the AMPK or mitogen-activated protein kinase (MAPK) pathways in the early stages of adipocyte differentiation. This is the first study on the anti-adipogenic effects of SSA and SSD, and further research in animals and humans is necessary to confirm the potential of saikosaponins as therapeutic agents for obesity.

Anti-influenza A Virus Effects and Mechanisms of Emodin and Its Analogs via Regulating PPARα/γ-AMPK-SIRT1 Pathway and Fatty Acid Metabolism.

The peroxisome proliferator-activated receptor (PPAR) α/γ-adenosine 5'-monophosphate- (AMP-) activated protein kinase- (AMPK-) sirtuin-1 (SIRT1) pathway and fatty acid metabolism are reported to be involved in influenza A virus (IAV) replication and IAV-pneumonia. Through a cell-based peroxisome proliferator responsive element- (PPRE-) driven luciferase bioassay, we have investigated 145 examples of traditional Chinese medicines (TCMs). Several TCMs, such as Polygonum cuspidatum, Rheum officinale Baillon, and Aloe vera var. Chinensis (Haw.) Berg., were found to possess high activity. We have further detected the anti-IAV activities of emodin (EMO) and its analogs, a group of common important compounds of these TCMs. The results showed that emodin and its several analogs possess excellent anti-IAV activities. The pharmacological tests showed that emodin significantly activated PPARα/γ and AMPK, decreased fatty acid biosynthesis, and increased intracellular ATP levels. Pharmaceutical inhibitors, siRNAs for PPARα/γ and AMPKα1, and exogenous palmitate impaired the inhibition of emodin. The in vivo test also showed that emodin significantly protected mice from IAV infection and pneumonia. Pharmacological inhibitors for PPARα/γ and AMPK signal and exogenous palmitate could partially counteract the effects of emodin in vivo. In conclusion, emodin and its analogs are a group of promising anti-IAV drug precursors, and the pharmacological mechanism of emodin is linked to its ability to regulate the PPARα/γ-AMPK pathway and fatty acid metabolism.

Rosmarinic acid exerts an antagonistic effect on nonalcoholic fatty liver disease by regulating the YAP1/TAZ-PPARγ/PGC-1α signaling pathway.

Rosmarinic acid (RA) is a water-soluble phenolic compound extracted from Boraginaceae and Lamiaceae. This study was designed to investigate the role and mechanism of action of RA in improving nonalcoholic fatty liver disease (NAFLD). Male SD rats maintained on a high fat diet and L02 cells stimulated with oleic acid were treated with RA. Our results showed that RA significantly reduced total cholesterol, triglycerides, low-density lipoprotein cholesterol, alanine aminotransferase, aspartate aminotransferase, and malondialdehyde levels and increased high-density lipoprotein cholesterol, superoxide dismutase and adenosine triphosphate levels both in vivo and in vitro. Hematoxylin and eosin staining and oil red O staining showed that RA had a good lipid-lowering effect and substantial protective effects on liver injury. Transmission electron microscopy and JC-1 fluorescence results showed that RA could improve mitochondrial damage in hepatocytes. Additionally, flow cytometry results indicated that RA inhibited ROS generation and apoptosis in L02 cells. The impaired hepatocytes were restored by using RA in NAFLD models characterized by down-regulating YAP1 and TAZ, meanwhile up-regulating PPARγ and PGC-1α. When YAP1 was over-expressed, RA reduced the expression of YAP1; however, the action of RA was significantly blocked by silencing YAP1. The experimental results indicated that RA markedly alleviated NAFLD by repairing mitochondrial damage and regulating the YAP1/TAZ-PPARγ/PGC-1α signaling pathway.

Erucic acid derived from rosemary regulates differentiation of mesenchymal stem cells into osteoblasts/adipocytes via suppression of peroxisome proliferator-activated receptor γ transcriptional activity.

Osteoporosis is associated with increase in fat tissue in bone marrow in humans. Mesenchymal stem cells in bone marrow are induced to differentiate into osteoblasts rather than adipocytes by the stimulation of peroxisome proliferator-activated receptor (PPAR) γ antagonists. PPARγ antagonists are expected to be useful to prevent osteoporosis by regulating the lineages of mesenchymal stem cells in bone marrow, as well as the prevention of obesity. In this study, we explored natural components suppressing PPARγ transcriptional activity in rosemary. Separation of active fraction of rosemary extract by repeated high performance liquid chromatograph and PPARγ luciferase reporter assay identified erucic acid, one of the monounsaturated fatty acids, as an active component. Twenty-five-micrometer erucic acid significantly decreased PPARγ luciferase activity and enhanced the differentiation of mouse-delivered C3H10T1/2 cells into osteoblasts rather than adipocytes. Furthermore, 25-µM erucic acid significantly decreased the expression of adipocyte marker genes, while accelerating osteoblast marker genes. In conclusion, erucic acid is a novel natural component derived from rosemary regulating mesenchymal stem cell differentiation via suppression of PPARγ transcriptional activity.

The effect of ginger supplementation on some immunity and inflammation intermediate genes expression in patients with active Rheumatoid Arthritis.

OBJECTIVE: Rheumatoid Arthritis (RA) is an autoimmune disease. The aim of this study was to investigate the effect of ginger supplementation on the expression of some immunity and inflammation intermediate genes in patients who suffer from RA. METHODS: In this randomized double-blind placebo-controlled clinical trial, seventy active RA patients were allocated randomly into two groups who either received 1500 mg ginger powder or placebo daily for 12 weeks. Disease activity score and gene expression of NF-κB, PPAR-γ, FoxP3, T-bet, GATA-3, and RORγt as immunity and inflammation intermediate factors were measured using quantitative real-time PCR before and after the intervention. RESULTS: After the intervention, FoxP3 genes expression increased significantly within ginger group and between the two groups (P-value = 0.02). Besides, T-bet and RORγt genes expression decreased significantly between the two groups (P-value < 0.05). In ginger group, PPAR-γ genes expression increased significantly (P-value = 0.047) but the difference between the two groups wasn't statistically significant (P-value = 0.12). The reduction in disease activity score was statistically significant within ginger group and between the two groups after the intervention. CONCLUSION: It seems that ginger can improve RA by decreasing disease manifestations via increasing FoxP3 genes expression and by decreasing RORγt and T-bet genes expression.

Novel Anti-Obesity Properties of Palmaria mollis in Zebrafish and Mouse Models.

(1) Background: The red seaweed Palmaria mollis (PM), which has a bacon-like taste, is increasingly being included in Western diets. In this study, we evaluate anti-obesity effects of PM using diet-induced obese (DIO) zebrafish and mice models. (2) Methods: We fed PM-containing feed to DIO-zebrafish and mice, and evaluated the anti-obesity effects We also analyzed gene expression changes in their liver and visceral adipose tissues (VAT). (3) Results: PM ameliorated several anti-obesity traits in both animals, including dyslipidaemia, hepatic steatosis, and visceral adiposity. In liver tissues of DIO-zebrafish and mice, PM upregulated gene expressions involved in peroxisome proliferator-activated receptor alpha (PPARA) pathways, and downregulated peroxisome proliferator-activated receptor gamma (PPARG) pathways, suggesting that the lipid-lowering effect of PM might be caused by activation of beta-oxidation and inhibition of lipogenesis. In VAT, PM downregulated genes involved in early and late adipocyte differentiation in zebrafish, but not in mice. (4) Conclusions: We have demonstrated that PM can prevent hepatic steatosis and visceral adiposity for the first time. Dietary supplementation of PM as a functional food may be suitable for obesity prevention and reduction in the prevalence of obesity-related diseases.

Ethanol extracts of Aster yomena (Kitam.) Honda inhibit adipogenesis through the activation of the AMPK signaling pathway in 3T3-L1 preadipocytes.

The leaves of Aster yomena (Kitam.) Honda have long been used as a traditional herb for treating disorders including coughs, asthma, and insect bites. According to recent studies, A. yomena leaf extracts have several pharmacological properties, including anti-inflammatory, antioxidant, and anti-asthmatic activities. However, little information is available regarding their anti-obesity effect. In this study, we investigated the inhibitory effect of the ethanol extracts of A. yomena leaves (EEAY) on adipocyte differentiation and adipogenesis using 3T3-L1 preadipocytes. When 3T3-L1 preadipocytes were treated with various concentrations of EEAY (ranging from non-toxic), the number of lipid droplets, lipid content, and triglyceride production, the typical characteristics of adipocytes, were suppressed in a concentration-dependent manner. During this process, EEAY significantly reduced the expression of adipogenic transcription factors, including peroxisome proliferator-activated receptor-γ, CCAAT/enhancer-binding protein α and ß, and sterol regulatory element-binding protein-1c. In addition, EEAY was also found to potently inhibit the expression of adipocyte-specific genes, including adipocyte fatty acid-binding protein and leptin. In particular, EEAY treatment effectively enhanced the activation of the AMP-activated protein kinase (AMPK) signaling pathway; however, the co-treatment with compound C, an inhibitor of AMPK, significantly restored the EEAY-induced inhibition of pro-adipogenic transcription factors and adipocyte-specific genes. These results indicate that EEAY may exert an anti-obesity effect by controlling the AMPK signaling pathway, suggesting that the leaf extract of A. yomena may be a potential anti-obesity agent.

6-Gingerol Suppresses Adipocyte-Derived Mediators of Inflammation In Vitro and in High-Fat Diet-Induced Obese Zebra Fish.

The present study was performed to investigate the molecular mechanism of 6-gingerol on adipocyte-mediated systemic inflammation in vitro and in high-fat diet-induced obese zebra fish. 6-Gingerol decreased adipogenesis due to the suppression of adipocyte differentiation markers, including peroxisome proliferator-activated receptor gamma, CCAATT enhancer binding protein α, and adipocyte protein 2, and triglyceride synthesis enzymes, including sterol regulatory element-binding protein-1, fatty acid synthase, lysophosphatidic acid acyltransferase, and acyl-coA : diacylglycerol acyltransferase 1, in 3T3-L1. A coculture insert system using 3T3-L1 with RAW 264.7 (coculture insert system using fully differentiated 3T3-L1 cells with RAW 264.7 macrophages) revealed that 6-gingerol increased anti-inflammatory cytokine interleukin-10. The expression of TNFα, monocyte chemotactic protein-1, interleukin-1ß, and interleukin-6 were decreased in the coculture insert system using fully differentiated 3T3-L1 cells with RAW 264.7 macrophages treated with 6-gingerol. Moreover, the coculture insert system using fully differentiated 3T3-L1 cells with RAW 264.7 macrophages treated with 6-gingerol inhibited the protein expression of TNFα and monocyte chemotactic protein-1 in RAW 264.7. 6-Gingerol decreased c-JUN N-terminal kinase and I kappa B kinase beta and its downstream target AP-1 expression in the coculture insert system using fully differentiated 3T3-L1 cells with RAW 264.7 macrophages. Furthermore, 6-gingerol decreased the expression of inducible nitric oxide synthase stimulated by the coculture insert system using fully differentiated 3T3-L1 cells with RAW 264.7 macrophages in RAW 264.7 and attenuated nitric oxide production in diet-induced obese zebra fish. Our results suggest that 6-gingerol suppresses inflammation through the regulation of the c-JUN N-terminal kinase-I kappa B kinase beta and its downstream targets.

Cajanus cajan- a source of PPARγ activators leading to anti-inflammatory and cytotoxic effects.

Cajanus cajan is an important legume crop in the human diet in many parts of the world. Due to its pharmacological properties, C. cajan is, moreover, used in traditional medicine for treating skin diseases, diabetes, inflammatory disorders and various other dysfunctions. In this study, we focused on the role of peroxisome proliferator-activated receptor gamma (PPARγ) as a potential therapeutic target of Cajanus cajan and its main compounds for the treatment of cancer, inflammation and inflammation-related disorders. The anti-inflammatory potential of C. cajan and its bioactive compounds and their cytotoxicity on the human cervical adenocarcinoma cell line HeLa, the human colorectal adenocarcinoma cell line CaCo-2 and the human breast adenocarcinoma cell line MCF-7 were elucidated. C. cajan and its compounds exerted significant anti-inflammatory activity on lipopolysaccharide-stimulated macrophages, showed good cytotoxic effects on the 3 different cancer cell lines and proved PPARγ activity in vitro. The main active compounds were orientin, pinostrobin and vitexin. Cajaninstilbene acid and pinosylvin monomethylether were identified as novel PPARγ activators. Based on these data, C. cajan provides excellent beneficial medicinal attributes and may be used as a potential food or a pharmaceutical supplement.

Potential role of marine algae extract on 3T3-L1 cell proliferation and differentiation: an in vitro approach.

BACKGROUND: From ancient times, marine algae have emerged as alternative medicine and foods, contains the rich source of natural products like proteins, vitamins, and secondary metabolites, especially Chlorella vulgaris (C. vulgaris) contains numerous anti-inflammatory, antioxidants and wound healing substances. Type 2 diabetes mellitus is closely associated with adipogenesis and their factors. Hence, we aimed to investigate the chemical constituents and adipogenic modulatory properties of C. vulgaris in 3T3-L1 pre-adipocytes. RESULTS: We analysed chemical constituents in ethanolic extract of C. vulgaris (EECV) by LC-MS. Results revealed that the EECV contains few triterpenoids and saponin compounds. Further, the effect of EECV on lipid accumulation along with genes and proteins expressions which are associated with adipogenesis and lipogenesis were evaluated using oil red O staining, qPCR and western blot techniques. The data indicated that that EECV treatment increased differentiation and lipid accumulation in 3T3-L1 cells, which indicates positive regulation of adipogenic and lipogenic activity. These increases were associated with up-regulation of PPAR-γ2, C/EBP-α, adiponectin, FAS, and leptin mRNA and protein expressions. Also, EECV treatments increased the concentration of glycerol releases as compared with control cells. Troglitazone is a PPAR-γ agonist that stimulates the PPAR-γ2, adiponectin, and GLUT-4 expressions. Similarly, EECV treatments significantly upregulated PPAR-γ2, adiponectin, GLUT-4 expressions and glucose utilization. Further, EECV treatment decreased AMPK-α expression as compared with control and metformin treated cells. CONCLUSION: The present research findings confirmed that the EECV effectively modulates the lipid accumulation and differentiation in 3T3-L1 cells through AMPK-α mediated signalling pathway.

A triterpenoid from wild bitter gourd inhibits breast cancer cells.

The antitumor activity of 3ß,7ß,25-trihydroxycucurbita-5,23(E)-dien-19-al (TCD), a triterpenoid isolated from wild bitter gourd, in breast cancer cells was investigated. TCD suppressed the proliferation of MCF-7 and MDA-MB-231 breast cancer cells with IC50 values at 72 h of 19 and 23 µM, respectively, via a PPARγ-independent manner. TCD induced cell apoptosis accompanied with pleiotrophic biological modulations including down-regulation of Akt-NF-κB signaling, up-regulation of p38 mitogen-activated protein kinase and p53, increased reactive oxygen species generation, inhibition of histone deacetylases protein expression, and cytoprotective autophagy. Together, these findings provided the translational value of TCD and wild bitter gourd as an antitumor agent for patients with breast cancer.

Potential role of marine algae extract on 3T3-L1 cell proliferation and differentiation: an in vitro approach

BACKGROUND: From ancient times, marine algae have emerged as alternative medicine and foods, contains the rich source of natural products like proteins, vitamins, and secondary metabolites, especially Chlorella vulgaris (C. vulgaris) contains numerous anti-inflammatory, antioxidants and wound healing substances. Type 2 diabetes mellitus is closely associated with adipogenesis and their factors. Hence, we aimed to investigate the chemical constituents and adipo-genic modulatory properties of C. vulgaris in 3T3-L1 pre-adipocytes. RESULTS: We analysed chemical constituents in ethanolic extract of C. vulgaris (EECV) by LC-MS. Results revealed that the EECV contains few triterpenoids and saponin compounds. Further, the effect of EECV on lipid accumulation along with genes and proteins expressions which are associated with adipogenesis and lipogenesis were evaluated using oil red O staining, qPCR and western blot techniques. The data indicated that that EECV treatment increased differentiation and lipid accumulation in 3T3-L1 cells, which indicates positive regulation of adipogenic and lipogenic activity. These increases were associated with up-regulation of PPAR-γ2, C/EBP-α, adiponectin, FAS, and leptin mRNA and protein expressions. Also, EECV treatments increased the concentration of glycerol releases as compared with control cells. Troglitazone is a PPAR-γ agonist that stimulates the PPAR-y2, adiponectin, and GLUT-4 expressions. Similarly, EECV treatments significantly upregulated PPAR-γ, adiponectin, GLUT-4 expressions and glucose utilization. Further, EECV treatment decreased AMPK-α expression as compared with control and metformin treated cells. CONCLUSION: The present research findings confirmed that the EECV effectively modulates the lipid accumulation and differentiation in 3T3-L1 cells through AMPK-α mediated signalling pathway.

In silico approach for the discovery of new PPARγ modulators among plant-derived polyphenols.

Peroxisome proliferator-activated receptor gamma (PPARγ) is a well-characterized member of the PPAR family that is predominantly expressed in adipose tissue and plays a significant role in lipid metabolism, adipogenesis, glucose homeostasis, and insulin sensitization. Full agonists of synthetic thiazolidinediones (TZDs) have been therapeutically used in clinical practice to treat type 2 diabetes for many years. Although it can effectively lower blood glucose levels and improve insulin sensitivity, the administration of TZDs has been associated with severe side effects. Based on recent evidence obtained with plant-derived polyphenols, the present in silico study aimed at finding new selective human PPARγ (hPPARγ) modulators that are able to improve glucose homeostasis with reduced side effects compared with TZDs. Docking experiments have been used to select compounds with strong binding affinity (ΔG values ranging from -10.0±0.9 to -11.4±0.9 kcal/mol) by docking against the binding site of several X-ray structures of hPPARγ. These putative modulators present several molecular interactions with the binding site of the protein. Additionally, most of the selected compounds have favorable druggability and good ADMET properties. These results aim to pave the way for further bench-scale analysis for the discovery of new modulators of hPPARγ that do not induce any side effects.

Hypoglycemic Activity through a Novel Combination of Fruiting Body and Mycelia of Cordyceps militaris in High-Fat Diet-Induced Type 2 Diabetes Mellitus Mice.

Diabetes mellitus (DM) is currently ranked among leading causes of death worldwide in which type 2 DM is reaching an epidemic proportion. Hypoglycemic medications for type 2 DM have either proven inadequate or posed adverse effects; therefore, the Chinese herbal products are under investigation as an alternative treatment. In this study, a novel combination of fruiting body and mycelia powder of herbal Cordyceps militaris number 1 (CmNo1) was administered to evaluate their potential hypoglycemic effects in high-fat diet- (HFD-) induced type 2 DM in C57BL/6J mice. Body weight, fasting blood glucose (FBG), oral glucose tolerance test (OGTT), and blood biochemistry indexes were measured. Results indicated that CmNo1 lowered the blood glucose level by increasing insulin sensitivity, while no change in body weight was observed. Increased protein expression of IRS-1, pIRS-1, AKT, pAKT, and GLUT-4 in skeletal muscle and adipose tissue was found indicating restoration of insulin signaling. Additionally, PPAR-γ expression in adipose tissue restored the triglyceride and cholesterol levels. Finally, our results suggest that CmNo1 possesses strong hypoglycemic, anticholesterolemic, and antihypertriglyceridemic actions and is more economical alternate for DM treatment.

Leishmanicidal compounds and potent PPARγ activators from Renealmia thyrsoidea (Ruiz & Pav.) Poepp. & Endl.

ETHNOPHARMACOLOGICAL RELEVANCE: Leaves and rhizomes of Renealmia thyrsoidea (Ruiz & Pav.) Poepp. & Endl. traditionally used in the Yanesha pharmacopoeia to treat skin infections such as leishmaniasis ulcers, or to reduce fever were chemically investigated to identify leishmanicidal compounds, as well as PPARγ activators. METHODS: Compounds were isolated through a bioassay-guided fractionation and their structures were determined via detailed spectral analysis. The viability of Leishmania amazonensis axenic amastigotes was assessed by the reduction of tetrazolium salt (MTT), the cytotoxicity on macrophage was evaluated using trypan blue dye exclusion method, while the percentage of infected macrophages was determined microscopically in the intracellular macrophage-infected assay. The CD36, mannose receptor (MR) and dectin-1 mRNA expression on human monocytes-derived macrophages was evaluated by quantitative real-time PCR. RESULTS: Six sesquiterpenes (1-6), one dihydrobenzofuranone (7) and four flavonoids (8-11) were isolated from the leaves. Alongside, two flavonoids (12-13) and five diarylheptanoids (14-18) were identified in the rhizomes. Leishmanicidal activity against Leishmania amazonensis axenic amastigotes was evaluated for all compounds. Compounds 6, 7, and 11, isolated from the leaves, showed to be the most active derivatives. Diarylheptanoids 14-18 were also screened for their ability to activate PPARγ nuclear receptor in macrophages. Compounds 17 and 18 bearing a Michael acceptor moiety strongly increased the expression of PPARγ target genes such as CD36, Dectin-1 and mannose receptor (MR), thus revealing interesting immunomodulatory properties. CONCLUSIONS: Phytochemical investigation of Renealmia thyrsoidea has led to the isolation of leishmanicidal compounds from the leaves and potent PPARγ activators from the rhizomes. These results are in agreement with the traditional uses of the different parts of Renealmia thyrsoidea.

6-iodolactone, key mediator of antitumoral properties of iodine.

An iodinated derivative of arachidonic acid, 5-hydroxy-6-iodo-8,11,14-eicosatrienoic acid, δ-lactone (6-IL) has been implicated as a possible intermediate in the autoregulation of the thyroid gland by iodine. In addition to antiproliferative and apoptotic effects observed in thyrocytes, this iodolipid could also exert similar actions in cells derived from extrathyroidal tissues like mammary gland, prostate, colon, or the nervous system. In mammary cancer (solid tumors or tumor cell lines), 6-IL has been detected after molecular iodine (I2) supplement, and is a potent activator of peroxisome proliferator-activated receptor type gamma (PPARγ). These observations led us to propose I2 supplement as a novel coadjutant therapy which, by inducing differentiation mechanisms, decreases tumor progression and prevents chemoresistance. Some kinds of tumoral cells, in contrast to normal cells, contain high concentrations of arachidonic acid, making the I2 supplement a potential "magic bullet" that enables local, specific production of 6-IL, which then exerts antineoplastic actions with minimal deleterious effects on normal tissues.

Walnut leaf extract inhibits PTP1B and enhances glucose-uptake in vitro.

ETHNOPHARMACOLOGICAL RELEVANCE: Walnut, Juglans regia L. (Juglandaceae), is one of the medicinal plants used to treat diabetic symptoms in Austrian folk medicine. The air-dried green leaves are either used as aqueous decoctions or liquor preparations and are consumed on a daily basis. We investigated the hypoglycemic effect of a methanolic Juglans regia leaf extract on glucose uptake, protein tyrosine phosphatase 1B (PTP1B) inhibition and peroxisome proliferator-activated receptor gamma (PPARγ) activation. MATERIAL AND METHODS: Hypoglycemic activity was assessed by glucose-uptake in C2C12 myocytes, inhibition of PTP1B and activation of PPARγ. Phytochemical characterization of the extract was carried out by LC-MS and GC-MS. RESULTS: Methanolic Juglans regia leaf extract enhanced the glucose uptake rate in C2C12 myocytes at concentrations of 25µg/mL compared to untreated cells. This activity may partly be explained by the inhibition of PTP1B but not PPARγ agonism. LC-MS analyses revealed chlorogenic acid (1), 3-p-coumaroylquinic acid (2), a trihydroxynaphthalene-hexoside (3), as well as eight flavonoids (4-11) as main phenolic constituents in the active extract. CONCLUSIONS: The finding that Juglans regia leaf extract enhances glucose uptake and inhibits PTP1B provides an in vitro-based rationale for the traditional use of walnut leaf preparations against elevated blood-glucose levels.

Screening of medicinal plants for PPARα and PPARγ activation and evaluation of their effects on glucose uptake and 3T3-L1 adipogenesis.

Medicinal plants are a rich source of ligands for nuclear receptors. The present study was aimed to screen a collection of plant extracts for PPARα/γ-activating properties and identify the active extract that can stimulate cellular glucose uptake without enhancing the adipogenesis. A reporter gene assay was performed to screen ethanolic extracts of 263 plant species, belonging to 94 families, for activation of PPARα and PPARγ. Eight extracts showed activation of PPARγ, while 22 extracts showed activation of PPARα. The extracts of five plants (Daphne gnidium, Illicium anisatum, Juniperus virginiana, Terminalia chebula, and Thymelaea hirsuta) showed activation of both PPARα and PPARγ and out of them, D. gnidium and T. hirsuta markedly increased PPARα/γ protein expression. All five extracts showed an increase in cellular glucose uptake. Of the five dual agonists, T. chebula and T. hirsuta did not show any increase in differentiation of 3T3-L1 preadipocytes, but I. anisatum caused an increase in adipogenesis, while D. gnidium and J. virginiana were toxic to adipocytes. The adipogenic effect of rosiglitazone was antagonized by T. chebula and T. hirsuta. It was concluded that T. hirsuta and T. chebula retain the property of elevating glucose uptake as PPARα/γ dual agonists without the undesired side effect of adipogenesis. This is the first report to reveal the PPARα/γ dual agonistic action and glucose uptake enhancing property of T. hirsuta and T. chebula.