New sesquiterpene glycoside ester with antiprotozoal activity from the flowers of Calendula officinalis L.

Continued chromatographic investigation of Calendula officinalis flowers led to the isolation of two sesquiterpenes, including one new, viridiflorol-10-O-ß-quinovopyranoside-2`-O-(3``-methyl-2``-pentenoate) (1), along with a previously reported compound viridiflorol-10-O-ß-fucopyranoside-2`-O-(3``-methyl-2``-pentenoate) (2). The new compound 1 was tested for antiprotozoal activity against Leishmania donovani Amastigote/THP1 and Trypanosoma brucei and it showed IC50 values of 3.57 and 7.84 µg/mL, respectively, while compound 2 exhibited no activity at the highest concentration tested 10 µg/mL.

A new anti-inflammatory flavonoid glycoside from tetraena aegyptia.

The chromatographic reinvestigation the methanol extract of Tetraena aegyptia led to the separation of a new flavonoid glycoside, isorhamnetin-3-O-[2```,3```-O-isopropylidene-α-L-rhamnopyranosyl]-(1```→6``)-O-ß-D-glucopyranoside (1), together with two known flavonoids, isorhamnetin (2) and isorhamnetin-3-O-glucoside (3), isolated for the first time from the plant. The new compound was evaluated for the anti-inflammatory activity by using LPS-induce RAW 264.7 cells model. Compound 1 showed significant inhibitory effect on NO release. ELISA assay showed a pronounced effect of 1 on the secretion of cytokines IL-6 and TNF-α, in a dose-dependent manner. Consistent results were obtained by qRT-PCR which revealed that compound 1 markedly reduced the mRNA expression of IL-6 and TNF-α. Together these data, we demonstrated the anti-inflammatory activity of compound 1.

Machaerinic acid 3-O-ß-D-glucuronopyranoside from Calendula officinalis.

Machaerinic acid 3-O-ß-D-glucuronopyranoside (1), along with ten known compounds (2-11) were isolated from the methanol extract of Calendula officinalis L. aerial parts. Their structures were confirmed by 1D and 2D NMR analysis and HRESIMS. Compound 1 was evaluated for the anti-proliferative activity against 95D and HT29 cancer cell lines and showed no cytotoxicity at the concentration of 100 µM.

Natural Aldose Reductase Inhibitor: A Potential Therapeutic Agent for Non-alcoholic Fatty Liver Disease.

Aldose reductase (AR) has been reported to be involved in the development of nonalcoholic fatty liver disease (NAFLD). Hepatic AR is induced under hyperglycemia condition and converts excess glucose to lipogenic fructose, which contributes in part to the accumulation of fat in the liver cells of diabetes rodents. In addition, the hyperglycemia-induced AR or nutrition-induced AR causes suppression of the transcriptional activity of peroxisome proliferator-activated receptor (PPAR) α and reduced lipolysis in the liver, which also contribute to the development of NAFLD. Moreover, AR induction in non-alcoholic steatohepatitis (NASH) may aggravate oxidative stress and the expression of inflammatory cytokines in the liver. Here, we summarize the knowledge on AR inhibitors of plant origin and review the effect of some plant-derived AR inhibitors on NAFLD/NASH in rodents. Natural AR inhibitors may improve NAFLD at least in part through attenuating oxidative stress and inflammatory cytokine expression. Some of the natural AR inhibitors have been reported to attenuate hepatic steatosis through the regulation of PPARα-mediated fatty acid oxidation. In this review, we propose that the natural AR inhibitors are potential therapeutic agents for NAFLD.

Myricetin Ameliorates Ethanol-Induced Lipid Accumulation in Liver Cells by Reducing Fatty Acid Biosynthesis.

SCOPE: Alcoholic liver disease is a serious threat to human health. The development of drug candidates from complementary and alternative medicines is an attractive approach. Myricetin can be found in fruit, vegetables, and herbs. This study investigates the protective effect of myricetin on ethanol-induced injury in mouse liver cells. METHODS AND RESULTS: Oil-red O staining, assays of oxidative stress and measurements of inflammatory markers in mouse AML12 liver cells collectively demonstrate that myricetin elicits a curative effect on ethanol-induced injury. Next, the role of myricetin in the metabolic regulation of ethanol pathology in liver cells is assessed by gas chromatography coupled with mass spectrometry. Myricetin inhibits ethanol-stimulated fatty acid biosynthesis. Additionally, dodecanoic acid may be proposed as a potential biomarker related to ethanol pathology or myricetin therapy. It is also observed that myricetin enhances ethanol-induced inhibition of the mitochondrial electron transport chain. Moreover, fumaric acid is found to be a candidate biomarker related to ethanol toxicity or myricetin therapy. Quantitative reverse-transcription-PCR shows that ethanol-induced fatty acid synthase and sterol regulatory element-binding protein-1c mRNA levels are alleviated by myricetin. Finally, myricetin increases ethanol-induced inhibition of phosphorylation of AMP-activated protein kinase. CONCLUSION: These results elucidate the pharmacological mechanism of myricetin on ethanol-induced lipid accumulation.

Curcumin improves alcoholic fatty liver by inhibiting fatty acid biosynthesis.

Alcoholic fatty liver is a threat to human health. It has been long known that abstinence from alcohol is the most effective therapy, other effective therapies are not available for the treatment in humans. Curcumin has a great potential for anti-oxidation and anti-inflammation, but the effect on metabolic reconstruction remains little known. Here we performed metabolomic analysis by gas chromatography/mass spectrometry and explored ethanol pathogenic insight as well as curcumin action pattern. We identified seventy-one metabolites in mouse liver. Carbohydrates and lipids were characteristic categories. Pathway analysis results revealed that ethanol-induced pathways including biosynthesis of unsaturated fatty acids, fatty acid biosynthesis and pentose and glucuronate interconversions were suppressed by curcumin. Additionally, ethanol enhanced galactose metabolism and pentose phosphate pathway. Glyoxylate and dicarboxylate metabolism and pyruvate metabolism were inhibited in mice fed ethanol diet plus curcumin. Stearic acid, oleic acid and linoleic acid were disease biomarkers and therapical biomarkers. These results reflect the landscape of hepatic metabolism regulation. Our findings illustrate ethanol pathological pathway and metabolic mechanism of curcumin therapy.

Effect of Trifolium pratense extract on methionine-choline-deficient diet-induced steatohepatitis in C57BL/6 mice.

AIM: The potential of Trifolium pratense (red clover) extract in the prevention of lipid disorder has attracted increasing attention in recent years. In this study, the aim was to determine whether and how red clover extract affected the development of murine diet-induced non-alcoholic steatohepatitis. METHODS: Non-alcoholic steatohepatitis was induced in C57BL/6 mice by feeding mice with a methionine-choline-deficient (MCD) diet. Hematoxylin and eosin staining was used for histological analyses. Real-time PCR was used to analyze the mRNA expression levels. RESULTS: Hepatic steatosis and necroinflammation was observed in MCD diet-fed mice, and this diet-induced steatosis was significantly attenuated, whereas liver inflammation was not significantly attenuated, by red clover extract treatment. Consistent with the results of H&E staining, the MCD diet-induced increase of liver triglycerides and cholesterol levels were significantly reduced by red clover extract treatment. However, with the improvement in hepatic steatosis, mRNA levels of acetyl CoA oxidase, carnitine palmitoyl transferase-1, and liver fatty acid-binding protein, three genes regulated by peroxisome proliferator-activated receptor (PPAR) α, were unaffected. CONCLUSION: Red clover extract alleviated MCD diet-induced hepatic steatosis, but did not ameliorate liver inflammation in C57BL/6 mice, and the improvement in hepatic steatosis was not through activating PPARα.

Biochanin A ameliorates the cytokine secretion profile of lipopolysaccharide-stimulated macrophages by a PPARγ-dependent pathway.

The role of peroxisome proliferator-activated receptors (PPARs) as anti-inflammatory mediators has been established, and the fact that some isoflavones are dual agonists of PPARα/γ indicates the involvement of PPARα and/or PPARγ in the anti-inflammatory action of certain isoflavones. However, the dependency of isoflavones on PPARs in their anti-inflammatory action has not been demonstrated. Here, we report the dependency of an isoflavone biochanin A and the independency of another isoflavone genistein in relation to PPARγ to ameliorate the cytokine secretion profile of lipopolysaccharide (LPS)-stimulated mouse RAW264.7 macrophages. A total amount of 10 µmol/l of biochanin A or genistein significantly suppressed the secretion of tumor necrosis factor α (TNFα) and interleukin-6 (IL-6) in LPS-induced RAW264.7 cells, whereas another two isoflavones, formononectin and daidzein, only significantly suppressed the secretion of IL-6. Their anti-inflammatory efficiencies were not in correspondence with their PPARα/γ agonist activities. Inhibition of PPARγ activity by its antagonist GW9662 significantly reversed the anti-inflammatory effect of biochanin A but not genistein, which demonstrated the dependency of biochanin A and the independency of genistein on PPARγ in their anti-inflammatory actions. Meanwhile, the PPARγ-dependency of biochanin A was further confirmed by the result that the suppression of LPS-induced NF-κB activation by biochanin A was reversed following GW9662 co-treatment. Moreover, inhibition of PPARα activity by its antagonist MK886 did not significantly reverse the anti-inflammatory effects of biochanin A and genistein, indicating that their anti-inflammatory properties were PPARα-independent.

Red clover extract ameliorates dyslipidemia in streptozotocin-induced diabetic C57BL/6 mice by activating hepatic PPARα.

The effects of red clover extract and its bioactive components, biochanin A and formononetin, on the blood glucose and lipid levels of streptozotocin (STZ) induced-diabetic mice were investigated. Male diabetic C57BL/6 mice were induced by multiple low-dose STZ administration and then treated with red clover extract or isoflavones for a period of 3 weeks. Red clover extract had no significant effect on lowering the blood glucose levels of STZ-diabetic mice. Similarly, biochanin A and formononetin exerted no hypoglycemic effect. However, the serum triglycerides, total cholesterols and low-density lipoprotein-cholesterol levels for STZ-diabetic mice receiving red clover extract were significantly lower than that of untreated STZ-diabetic mice. In addition, treatment with biochanin A or formononetin significantly ameliorated these lipid profiles in diabetic mice. The mRNA expression of two target genes transcriptionally regulated by peroxisome proliferator-activated receptor (PPAR) α were determined by semi-quantitative RT-PCR and biochanin A or formononetin were found to significantly down-regulate hepatic APOC3 expression, whereas they had no significant effect on hepatic APOA5 expression. Thus we conclude that red clover extract and biochanin A or formononetin significantly ameliorate the lipid profiles of STZ-diabetic mice and these effects are achieved at least in part by activating hepatic PPARα.

Intraperitoneal co-administration of thymosin alpha-1 ameliorates streptozotocin-induced pancreatic lesions and diabetes in C57BL/6 mice.

We investigated the effects of the in vivo administration of thymosin alpha-1 (Talpha-1) on streptozotocin (STZ)-induced pancreatic lesions and diabetes. Mice were randomly divided into four experimental groups: normoglycemic control, STZ-treated, STZ plus 0.1 microg/kg body weight/day Talpha-1-treated, and STZ plus 1 microg/kg/day Talpha-1-treated. Blood glucose was assayed periodically, and serum insulin was determined at the end of the experiment using the ELISA Kit. Aldehyde fuchsin staining was used for histopathological examination of the pancreas. Parameters for oxidative stress were measured with pancreatic malondialdehyde (MDA) level, glutathione (GSH) content and enzymatic activities of superoxide dismutase and catalase. Fourteen days after the initiation of Talpha-1 treatment and up to day 35 when the treatment was stopped, both of the two STZ and Talpha-1-co-treated mouse groups had significant lower levels of blood glucose than the STZ-treated but Talpha-1-untreated mice, although both remained higher than that of the normoglycemic controls. At the end of the Talpha-1 treatment, the serum insulin level for STZ-treated mice receiving 1 microg/kg/day Talpha-1 for 35 days was 2-fold (P<0.001) as much as that of the Talpha-1-untreated STZ-diabetic mice, although not completely restored to the normal level. Pancreatic aldehyde fuchsin staining showed that STZ treatment caused significant pancreatitis, islet atrophy, and a significant reduction in the number of pancreatic beta cells. These histological lesions, however, were significantly alleviated by 1 microg/kg/day Talpha-1 treatment for 35 days. Furthermore, compared with the Talpha-1- untreated STZ-diabetic mice, the pancreatic GSH level of the 1 microg/kg/day Talpha-1-treated STZ-induced mice was 1.92-fold that of the untreated STZ-induced mice (P<0.01), whereas the pancreatic MDA level was only 81.9% that of the untreated STZ-diabetic mice (P<0.05). Together these results demonstrate that co-administration of Talpha-1 leads to significant protection against STZ-induced pancreatic damage and diabetes, and part of the protection might be achieved through enhancing pancreatic antioxidative capability.