Neuroprotective Effects of Ethanol Extract (EEPG) Against Glutamate Induced Neurotoxicity in HT22 Cells.

Oxidative stress induced by glutamate is a significant contributor to neuronal cell damage and can lead to neurodegenerative diseases such as Alzheimer's, Huntington's, and ischemic brain injury. At the cellular level, oxidative stress increases Ca ion influx and reactive oxygen species (ROS), which activate the MAPK signaling pathway. Additionally, the generation of ROS causes mitochondrial dysfunction, triggering apoptosis by promoting the translocation of AIF to the nucleus from the mitochondria.

LC-MS/MS analysis and -glucosidase inhibitory effect of majonoside R2 in Vietnamese ginseng ( Ha & Grushv.).

Majonoside R2 (MR2), the principal saponin of Vietnamese ginseng ( Ha & Grushv.), has the unique structure of ocotillol-type dammarane and showed remarkable biological activities. This paper deals with the new findings in the chemical analysis MR2 by the tandem LC-MS/MS and, especially, its inhibitory activities on -glucosidase for diabetic management.

Panaxindole, a novel indole alkaloid N-glucoside from the leaves of Panax vietnamensis Ha et Grushv. (Vietnamese ginseng).

Vietnamese ginseng (Panax vietnamensis Ha and Grushv., Araliaceae) is indigenous in the central highlands of Vietnam and the southernmost distribution in the Panax genus. Like other ginseng, Vietnamese ginseng is well known has been used as a tonic and for management of certain diseases in the traditional medicine.

Neuroprotective Effects of Ethanol Extract of (EEPF) against Glutamate-Mediated Neuronal Toxicity in HT22 Cells.

In traditional herbal medicine, the has been frequently used for the treatment of ischemia and inflammation. Oxidative stress mediated by elevated glutamate levels cause neuronal cell death in ischemia and various neurodegenerative diseases. However, so far, the neuroprotective effects of this plant extract against glutamate-mediated cell death have not been investigated in cell models.

Unique guanidine-conjugated catechins from the leaves of Alchornea rugosa and their autophagy modulating activity.

Natural guanidines, molecules that contain the guanidine moiety, are structurally unique and often exhibit potent biological activities. A phytochemical investigation of the leaves of Alchornea rugosa (Lour.) Müll.

Antidiabetic Activity of Gagnep. Extract against High-Fat Diet and Alloxan-Induced Type 2 Diabetes in Mice.

So far, diabetes mellitus has become a health threat to society all over the world. Especially, people with diabetes have always coped with complications related to this disease and unexpected side effects of synthetic drugs. Thus, there has been a current trend for researchers to find out new natural ingredients which were safer and still effective in the treatment of diabetes.

Rugonidines A-F, Diastereomeric 1,6-Dioxa-7,9-diazaspiro[4.5]dec-7-en-8-amines from the Leaves of .

Rugonidines A-F (-), three pairs of novel configurationally semistable diastereomers featuring an unprecedented 1,6-dioxa-7,9-diazaspiro[4.5]dec-7-en-8-amine scaffold, were isolated from based on MS/MS-based molecular networking analysis. Their structures were elucidated by NMR spectroscopy in combination with quantum-chemical calculations.

Configurational Assignment of a Flexible Benzo[]isochromene Stereodiad from and Inhibition of Soluble Epoxide Hydrolase Activity.

A new benzo[]isochromene possessing a conformationally mobile moiety was identified from . The 2D structure was established utilizing spectrometric and spectroscopic techniques with variable temperatures. The configurational investigation of the flexible moiety was investigated utilizing contemporary NMR-combined computational tools such as DP4, direct -DP4, and DP4 Plus.

A new triterpenoid from the stems of with antiproliferative activity.

A series of schiartane C nortriterpenoids with 5/5/7/6/5 membered consecutive rings (‒) with an unique schinortriterpenoid skeleton including a new, kadcoccilactone V (), together with four known ones (‒) and three known triterpenoids (‒) were identified from stems of (Lem.) A. C.

Chemical constituents from the roots of Kadsura coccinea with their protein tyrosine phosphatase 1B and acetylcholinesterase inhibitory activities.

Kadsura coccinea (Lem.) A. C.

Oligosaccharide and glucose esters from the roots of .

The root of plant has been used in the Oriental medicine as a tonic and for the treatment of certain diseases. Our current research on phytochemical profile of the roots of led to the isolation of a new oligosaccharide ester (, polygaloside), a new glucose ester (, arillatoside), along with five known sucrose esters (-). Their structures were elucidated on the basis of extensive chemical and spectroscopic methods as well as comparison with those reported in the literature.

NMR-Based Investigation of Hydrogen Bonding in a Dihydroanthracen-1(4 H)one from Rubia philippinensis and Its Soluble Epoxide Hydrolase Inhibitory Potential.

Hydrogen bonding is a vital feature of a large ensemble of chemical structures. Soluble epoxide hydrolase (sEH) has been targeted for development of the treatment for inflammation-associated diseases. Compounds 1 and 2 were purified from Rubia philippinensis, and their structures were established via physical data analysis.

A natural ent‑kaurane diterpenoid induces antiproliferation in ovarian cancer cells via ERK1/2 regulation and inhibition of cellular migration and invasion.

Ovarian cancer is one of the most common causes of female mortalities from gynecological tumors. An ent‑kaurane diterpenoid compound CRT1 (ent‑18‑acetoxy‑7β‑hydroxy kaur‑15‑oxo‑16‑ene), mainly isolated from the Vietnamese herb Croton tonkinesis has been used in folk medicine in Vietnam for cancer treatment. However, the effect of this compound on human ovarian cancer cells has not yet been reported.

Antiproliferative activity and apoptosis induction by trijuganone C isolated from the root of Salvia miltiorrhiza Bunge (Danshen).

In this study, we found that the hexane fraction of Danshen, the dried root of Salvia miltiorrhiza (Lamiaceae), exerted antiproliferative effects on human leukemia cells. Phytochemical investigation of the hexane fraction achieved the isolation of the tanshinone diterpenes: dihydrotanshinone I (1), trijuganone C (2), trijuganone B (3), cryptotanshinone (4), tanshinone IIA (5), and tanshinone I (6). Compound 2 showed significant antiproliferative activities against human leukemia cells HL-60, Jurkat, and U937.

Xanthine oxidase inhibitors from Archidendron clypearia (Jack.) I.C. Nielsen: Results from systematic screening of Vietnamese medicinal plants.

Objective: To screen Vietnamese medicinal plants for xanthine oxidase (XO) inhibitory activity and to isolate XO inhibitor(s) from the most active plant.

Methods: The plants materials were extracted by methanol. The active plant materials were fractionated using different organic solvents, including n-hexane, ethyl acetate, and n-butanol.

Cytotoxic and apoptosis-inducing activities against human lung cancer cell lines of cassaine diterpenoids from the bark of Erythrophleum fordii.

A phytochemical investigation into the bark of Erythrophleum fordii yielded four new compounds, two new cassaine diterpenoids (erythrofordin T and U, 1 and 2) and two new cassaine diterpenoid amines (erythroformine A and B, 6 and 7), as well as nine known compounds. We report for the first time the isolation of erythrofordin V (3) from a natural source and that of the remaining eight known diterpenoids (4-5, 8-13) from E. fordii.

Anti-Hyperuricemic, Anti-Inflammatory and Analgesic Effects of Siegesbeckia orientalis L. Resulting from the Fraction with High Phenolic Content.

Background: The medicinal plant Siegesbeckia orientalis L. has been commonly used for the treatment of acute arthritis, rheumatism, and gout in Vietnam. However, pharmacological research of this plant associated with gout has not been reported.

Pentacyclic Triterpenoids from Astilbe rivularis that Enhance Glucose Uptake via the Activation of Akt and Erk1/2 in C2C12 Myotubes.

Glucose uptake into insulin-sensitive tissues is important for the regulation of blood glucose. This study has investigated whether the pentacyclic triterpenoids substituted with a carboxylic acid at the C-27 position isolated from Astilbe rivularis can enhance glucose uptake and subsequently to also examine their underlying molecular mechanisms. The structure of the new pentacyclic triterpenoid 1 was assigned by spectroscopic data interpretation.

Cytotoxic constituents from the seeds of Vietnamese Caesalpinia sappan.

Context: Caesalpinia sappan Linn. (Leguminosae) has been used in folk medicines for the treatment of many diseases. The heartwood of this plant contains various phenolic components with interesting biological applications; however, the chemical and biological potentials of the seed of this plant have not been fully explored.

ent-kaurane diterpenoids from Croton tonkinensis induce apoptosis in colorectal cancer cells through the phosphorylation of JNK mediated by reactive oxygen species and dual-specificity JNK kinase MKK4.

To search for new chemotherapeutic agents to treat colorectal cancer, we isolated a number of natural ent-kaurane diterpenoids from the plant Croton tonkinensis. Among them, only CeKDs with the 15-oxo-16-ene moiety induced the apoptosis of colorectal cancer cell lines Caco-2 and LS180. The active CeKD induced the activation of ERK and JNK, but the inactive ones induced that of ERK, but not that of JNK.

Cytotoxic and anti-tumor activities of lignans from the seeds of Vietnamese nutmeg Myristica fragrans.

Four lignans, meso-dihydroguaiaretic acid (DHGA), macelignan, fragransin A2 and nectandrin B, were isolated from the seeds of Myristica fragrans (Vietnamese nutmeg) and investigated for their cytotoxic activity against eight cancer cell lines. Of these, DHGA exhibited potent cytotoxicity against H358 with IC50 value of 10.1 μM.

Anticancer activity of pristimerin in epidermal growth factor receptor 2-positive SKBR3 human breast cancer cells.

Pristimerin is a naturally occurring triterpenoid that causes cytotoxicity in several cancer cell lines. However, the mechanism of action for the cytotoxic effect of pristimerin has not been unexplored. The purpose of this study was to investigate the effect of pristimerin on cytotoxicity using the epidermal growth factor receptor 2 (HER2)-positive SKBR3 human breast cancer cell line.

An ent-kaurane diterpenoid from Croton tonkinensis induces apoptosis by regulating AMP-activated protein kinase in SK-HEP1 human hepatocellular carcinoma cells.

Hepatocellular carcinoma (HCC) is the most common type of liver cancer with high mortality worldwide. Traditional chemotherapy for HCC is not widely accepted by clinical practitioners because of its toxic side effects. Thus, there is a need to identify chemotherapeutic drugs against HCC.

Xanthones from Polygala karensium inhibit neuraminidases from influenza A viruses.

The emergence of the H1N1 swine flu pandemic has the possibility to develop the occurrence of disaster- or drug-resistant viruses by additional reassortments in novel influenza A virus. In the course of an anti-influenza screening program for natural products, 10 xanthone derivatives (1-10) were isolated by bioassay-guided fractionation from the EtOAc-soluble extract of Polygala karensium. Compounds 1, 3, 5, 7, and 9 with a hydroxy group at C-1 showed strong inhibitory effects on neuraminidases from various influenza viral strains, H1N1, H9N2, novel H1N1 (WT), and oseltamivir-resistant novel H1N1 (H274Y) expressed in 293T cells.