Youbin Li

A novel diarylheptanoid-bearing sesquiterpene moiety from the rhizomes of Alpinia officinarum

Abstract A new diarylheptanoid analogue-bearing sesquiterpene moiety, named Alpinisin A, was isolated from the rhizomes of Alpinia officinarum Hance. The new structure was determined by various spectroscopic techniques 1H-nuclear magnetic resonance (1H NMR), 13C-attached proton test (13C-APT), heteronuclear single quantum coherence (HSQC), heteronuclear multiple bond correlation (HMBC), 1H-1H correlation spectroscopy (1H–1HCOSY), nuclear overhauser effect spectroscopy (NOESY) and high resolution electrospray ionization mass spectrometry (HR–ESI–MS). The compound was tested for cytotoxic activity in vitro against human tumour cell lines (gastric carcinoma cell -7901 (SGC-7901), Michigan Cancer Foundation-7 (MCF-7) and Caski), which showed significant inhibitory effects with IC50 levels of 11.42, 15.14 and 14.78 μM, respectively. The novel chemical structure characterised with a diarylheptanoid linked to a chain-like sesquiterpenoid should be highlighted.

Tadehaginosides A–J, Phenylpropanoid Glucosides from Tadehagi triquetrum, Enhance Glucose Uptake via the Upregulation of PPARγ and GLUT-4 in C2C12 Myotubes

Ten new phenylpropanoid glucosides, tadehaginosides A-J (1-10), and the known compound tadehaginoside (11) were obtained from Tadehagi triquetrum. These phenylpropanoid glucosides were structurally characterized through extensive physical and chemical analyses. Compounds 1 and 2 represent the first set of dimeric derivatives of tadehaginoside with an unusual bicyclo[2.2.2]octene skeleton, whereas compounds 3 and 4 contain a unique cyclobutane basic core in their carbon scaffolds. The effects of these compounds on glucose uptake in C2C12 myotubes were evaluated. Compounds 3-11, particularly 4, significantly increased the basal and insulin-elicited glucose uptake. The results from molecular docking, luciferase analyses, and ELISA indicated that the increased glucose uptake may be due to increases in peroxisome proliferator-activated receptor γ (PPARγ) activity and glucose transporter-4 (GLUT-4) expression. These results indicate that the isolated phenylpropanoid glucosides, particularly compound 4, have the potential to be developed into antidiabetic compounds.

Tadehaginoside modulates lipogenesis and glucose consumption in HepG2 cells

Tadehaginoside (TS) is a phenylpropanoid glycoside found in Tadehagi triquetrum, a medicinal plant with multiple biological activities. This study investigated the effect of TS on lipogenesis and glucose consumption in HepG2 cells. Treatment with TS inhibited lipid accumulation in a dose-dependent manner. This inhibition was closely associated with the downregulation of lipogenic genes such as SREBP-1a, SREBP-2 and their downstream targets (FAS, ACC, HMGR) and the upregulation of lipolytic gene PPARα as revealed by real-time quantitative PCR. Further investigation showed that TS significantly stimulated glucose consumption by HepG2 cells and glucose uptake by C2C12 myotubes, which could be partially explained by the upregulation of PPARγ. Collectively, these results clearly indicate that TS is an effective regulator of lipogenesis and glucose consumption, which could be useful in treatment of obesity and diabetes.

New 2-Benzoxazolinone Derivatives with Cytotoxic Activities from the Roots of Acanthus ilicifolius

Four new 2-benzoxazolinone-type alkaloids (acanthosides A-D) along with three known ones were isolated from the roots of Acanthus ilicifolius. Their structures were established by detailed interpretation of one dimensional (1D)- and two dimensional (2D)-NMR as well as high-resolution electrospray ionization (ESI)-MS data. The antiproliferative activities of these compounds were evaluated in vitro against three cultured cancer cell lines. The new compounds exhibited different levels of cytotoxicity against the HepG2, HeLa, and A-549 cancer cell lines with IC50 range 7.8-26.6 µM. In comparison with known compounds, the new isolates displayed better cytotoxic activities, which was attributable to the presence of substituted benzoyl moiety in their structures.

A new diarylheptanoid from Alpinia officinarum promotes the differentiation of 3T3-L1 preadipocytes

Abstract A new diarylheptanoid, namely trans-(4R,5S)-epoxy-1,7-diphenyl-3-heptanone (1), and a new natural product, 7-(4″-hydroxy-3″-methoxyphenyl)-1-phenyl-hepta-4E,6E-dien-3-one (2), were obtained from the aqueous extract of Alpinia officinarum Hance, together with three other diarylheptanoids, 5-hydroxy-1,7-diphenyl-3-heptanone (3), 1,7-diphenyl-4E-en-3-heptanone (4) and 5-methoxy-1,7-diphenyl-3-heptanone (5). The structures were characterised mainly by analysing their physical data including IR, NMR and HRMS. This study highlights that the 4,5-epoxy moiety in 1 is rarely seen in diarylheptanoids. In addition, the five isolates were tested for their differentiation activity of 3T3-L1 preadipocytes. The results showed that these compounds could dose-dependently promote adipocyte differentiation without cytotoxicity (IC50 > 100 μM).

Anti-hyperglycemic and anti-hyperlipidemia effects of the alkaloid-rich extract from barks of Litsea glutinosa in ob/ob mice

The present study investigated the anti-hyperglycemic and anti-hyperlipidemia effects of the alkaloid-rich extract from Litsea glutinosa barks (CG) in ob/ob mice. CG was orally administrated (50, 100 and 200 mg/kg) to ob/ob mice for 4 weeks. Parameters of glucose metabolism, hepatotoxicity, hyperlipidemia and inflammation were measured. CG was chemically characterized using UPLC-QTOF-MS. CG dose-dependently decreased body and fat weights without reducing average food intake. CG (100–200 mg/kg) significantly reduced the serum levels of fasting glucose, glycosylated hemoglobin (HbAlc) and glycosylated serum protein (GSP). CG increased insulin sensitivity as manifested by decreased fasting serum insulin, reduced homeostasis model assessment-estimated insulin resistance (HOMA-IR) and improved oral glucose tolerance. CG also alleviated dyslipidemia, ameliorated liver steatosis, increased the activity of serum lipase and alleviated inflammation. The activities of liver pyruvate kinase and glucokinase as well as liver content of glycogen were increased after CG treatment. CG was rich in alkaloids and eight main alkaloids were identified, many of which had been demonstrated to possess adequate anti-diabetic activities. These results suggest that the alkaloid-rich extract of CG possesses potential anti-hyperglycemic and anti-hyperlipidemic effects and can be utilized as an effective agent for the treatment of type 2 diabetes.

Bioassay-directed fractionation of a blood coagulation factor Xa inhibitor, betulinic acid from Lycopus lucidus

Abstract Thrombosis is a major cause of morbidity and mortality worldwide and plays a pivotal role in the pathogenesis of several cardiovascular disorders, including acute coronary syndrome, unstable angina, myocardial infarction, sudden cardiac death, peripheral arterial occlusion, ischemic stroke, deep-vein thrombosis, and pulmonary embolism. Anticoagulants, antiplatelet agents, and fibrinolytics can reduce the risks of these clinical events. Especially, the blood coagulation factor Xa (FXa) inhibitor is a proven anticoagulant. Promoting blood circulation, using traditional Chinese medicine (TCM), for the treatment of these diseases has been safely used for thousands of years in clinical practice. Therefore, highly safe and effective anticoagulant ingredients, including FXa inhibitors, could be found in TCM for activating the blood circulation. One FXa inhibitor, a pentacyclic triterpene (compound 1, betulinic acid) characterized by IR, MS and NMR analyses, was isolated from the ethyl acetate fraction of Lycopus lucidus by bioassay-directed fractionation. Compound 1 exhibited an inhibitory effect on FXa with IC50 25.05 μmol/L and reduced the thrombus weight in an animal model at 25-100 mg/kg. These results indicate that betulinic acid could be the potential for anticoagulant therapy.