Identification of a ß-Carboline Alkaloid from Chemoselectively Derived Vanilla Bean Extract and Its Prevention of Lipid Droplet Accumulation in Human Hepatocytes (HepG2).

Targeting bioactive compounds to prevent lipid droplet accumulation in the liver, we explored an antioxidative extract from vanilla bean (Vainilla planifolia) after chemo-selective derivatization through heating and acid modification. The chemical analysis of vanilla bean extract through chemoselective derivatization resulted in the identification of sixteen compounds (34-50) using LC-MS/MS analysis. A ß-carboline alkaloid with a piperidine C-ring and a vanillin moiety at C-1 (34) was identified by molecular networking and diagnostic fragmentation filtering approaches. ß-carboline alkaloid 34 exhibited significant inhibitory activity of lipid droplet accumulation (LDAI) in oleic acid-loaded hepatocellular carcinoma HepG2 cells. The LDAI activity was associated with both activation of lipolysis and suppression of lipogenesis in the cells. The study indicates that crude plant extracts, following chemoselective derivatization, may contain bioactive compounds that could be beneficial in preventing hepatosteatosis and could serve as a source of lead compounds for drug development. This approach may be useful to investigate other mixtures of natural products and food resources.

Abietane diterpenes from Abies spectabilis and their anti-pancreatic cancer activity against the MIA PaCa-2 cell line.

An ethanolic extract of the stem of Abies spectabilis exhibited strong cytotoxicity against MIA PaCa-2 human pancreatic cancer cells preferentially under nutrient-deprived conditions. Therefore, phytochemical investigation of this bioactive extract was carried out, and that led the isolation of ten compounds (1-10) including a new abietane-type diterpene (1). The structure of the new compound (1) was elucidated by combined spectroscopic techniques, including HRFABMS, NMR and quantum ECD calculation. All the isolated compounds were evaluated for their efficacy against MIA PaCa-2 human pancreatic cancer cell line by employing an anti-austerity strategy. Among the tested compounds, dehydroabietinol (5) displayed the most potent activity with a PC50 value of 6.6 µM. Dehydroabietinol (5) was also found to retard the MIA PaCa-2 cell migration under normal nutrient-rich conditions displaying its anti-metastatic potential. Investigation on the mechanism suggested that dehydroabietinol (5) is an inhibitor of the key cancer cell survival Akt/mTOR/autophagy signaling pathway.

Anti-inflammatory effects of Morus alba Linne bark on the activation of toll-like receptors and imiquimod-induced ear edema in mice.

BACKGROUND: Morus alba L. bark has been widely used in traditional medicine for treating several inflammatory diseases, such as hypertension, diabetes mellitus and coughing; however, the molecular mechanisms underlying its anti-inflammatory effects are not well understood. METHODS: We examined the effects of an extract of Morus alba L. bark (MabE) on Toll-like receptor (TLR) ligand-induced activation of RAW264.7 macrophages using a luciferase reporter assay and immunoassays. For the in vivo experiment, we used an imiquimod-induced ear edema model to examine the anti-inflammatory effects of MabE. RESULTS: MabE inhibited the TLR ligand-induced activation of NF-κB in RAW264.7 cells without affecting their viability. Consistent with the inhibition of NF-κB activation, MabE also inhibited the production of IL-6 and IL-1ß from TLR ligand-treated RAW264.7 cells. In vivo MabE treatment inhibited the ear swelling of IMQ-treated mice, in addition to the mRNA expression of IL-17A, IL-1ß and COX-2. The increases in splenic γδT cells in IMQ-treated mice and the production of IL-17A from splenocytes were significantly inhibited by MabE treatment. CONCLUSION: Our study suggests that the anti-inflammatory effects of MabE on the activation of the macrophage cell line RAW246.7 by TLRs and IMQ-induced ear edema are through the inhibition of NF-κB activation and IL-17A-producing γδT cells, respectively.

Anti-Austerity Activity of Thai Medicinal Plants: Chemical Constituents and Anti-Pancreatic Cancer Activities of Kaempferia parviflora.

Human pancreatic tumor cells have an intrinsic ability to tolerate nutrition starvation and survive in the hypovascular tumor microenvironment, the phenomenon termed as "austerity". Searching for an agent that inhibits such tolerance to nutrient starvation and kills the pancreatic cancer cells preferentially in nutrient-starvation is a unique anti-austerity strategy in anti-cancer drug discovery. In this strategy, plant extracts and compounds are tested against PANC-1 human pancreatic cancer cell line under the conditions of nutrient-deprived medium (NDM) and nutrient-rich medium (DMEM), to discover the compounds that show selective cytotoxicity in NDM. Screening of twenty-five Thai indigenous medicinal plant extracts for their anti-austerity activity against the PANC-1 human pancreatic cancer cell line in nutrient deprived medium (NDM) resulted in the identification of four active plants, Derris scandens, Boesenbergia pandurata, Citrus hystrix, and Kaempferia parviflora, with PC50 values 0.5-8.9 µg/mL. K. parviflora extract also inhibited PANC-1 cancer cell colony formation. Phytochemical investigation of K. parviflora extract led to the isolation of fourteen compounds, including two polyoxygenated cyclohexanes (1 and 2), eleven flavonoids (3-13), and ß-sitosterol (14). Stereochemical assignment of compound 1 was confirmed through X-ray analysis. All isolated compounds were tested for their preferential cytotoxicity against PANC-1 cells. Among them, 5-hydroxy-7-methoxyflavone (3) displayed the most potent activity with a PC50 value of 0.8 µM. Mechanistically, it was found to induce apoptosis in PANC-1 cell death in NDM as evident by caspase cleavage. It was also found to inhibit PANC-1 cancer cell colony formation in DMEM. Therefore, compound 3 can be considered as a potential lead compound for the anticancer drug development based on the anti-austerity strategy.

Chemical constituents from Artemisia vulgaris and their antiausterity activities against the PANC-1 human pancreatic cancer cell line.

The 70% ethanolic extract of Artemisia vulgaris showed preferential cytotoxicity against PANC-1 human pancreatic cancer cells under a nutrient-deprived condition with PC50 12.5 µg/mL. A phytochemical investigation of this extract yielded a new bicyclic [4:3:0] sesquiterpene named (+)-vulgaric acid (1), together with eight previously reported compounds. The structural elucidation of 1 was achieved by HRFABMS and NMR analysis. The absolute configuration of 1 was deduced by computational calculations of ECD data. All isolated compounds were tested for preferential cytotoxicity against PANC-1 cells, and apigenin (3) showed the strongest activity with PC50 30.7 µM.

Fragranone C: a new dihydrochalcone glucopyranoside from Anneslea fragrans twigs.

A phytochemical investigation of an ethanolic extract of Anneslea fragrans twigs collected from Thailand resulted in the discovery of a new dihydrochalcone glucopyranoside named fragranone C (1), together with six previously reported compounds. The structural elucidation of the new compound was achieved by HRFABMS, NMR spectroscopic analysis and acid hydrolysis.[Figure: see text].

Antiausterity Activity of Secondary Metabolites from the Roots of Ferula hezarlalehzarica against the PANC-1 Human Pancreatic Cancer Cell Line.

Human pancreatic cancer is one of the most aggressive types of cancer, with a high mortality rate. Due to the high tolerance of such cancer cells to nutrient starvation conditions, they can survive in a hypovascular tumor microenvironment. In this study, the dichloromethane extract of the roots of Ferula hezarlalehzarica showed potent preferential cytotoxic activity with a PC50 value of 0.78 µg/mL. Phytochemical investigation of this extract led to the isolation of 18 compounds, including one new sesquiterpenoid (6) and one new monoterpenoid (18). All isolated compounds were evaluated for their preferential cytotoxicity against PANC-1 human pancreatic cancer cells by employing an antiausterity strategy. Among them, ferutinin (2) was identified as the most active compound, with a PC50 value of 0.72 µM. In addition, the real-time effect of ferutinin (2) and compound 6 against PANC-1 cells, exposed to a nutrient-deprived medium (NDM), showed cell shrinkage, leading to cancer cell death within a short period of exposure. Compounds 2 and 6 also inhibited colony formation of PANC-1 cells. The present study indicates that the dichloromethane extract of the roots of F. hezarlalehzarica is a rich source of bioactive compounds for targeting PANC-1 cells.

Orengedokuto and san'oshashinto improve memory deficits by inhibiting aging-dependent activation of glycogen synthase kinase-3ß.

BACKGROUND AND AIM: The aging-dependent activation of glycogen synthase kinase-3ß (GSK-3ß) has been suggested to be important in the onset of dementia. To discover novel therapeutic Kampo medicines for dementia, we examined the effects of orengedokuto (OGT; huáng lián jiedú tang) and san'oshashinto (SST; san huáng xiè xin tang) on memory deficits and GSK-3ß activity in senescence-accelerated prone mice (SAMP8). EXPERIMENTAL PROCEDURE: The object recognition test (ORT) and conditioned fear memory test (CFT) were employed to elucidate short-term working memory and long-term fear memory. The activity of GSK-3ß and the phosphorylation of related molecules were measured using a kinase assay and Western blotting. RESULTS AND CONCLUSION: OGT and SST attenuated memory deficits in SAMP8 in ORT, but not in CFT. In ex vivo experiments, cortical GSK-3ß activity was significantly stronger in SAMP8 than in SAMR1. The enhanced cortical GSK-3ß activity in SAMP8 was accompanied by a significant increase in the level of phosphorylated collapsin response mediator protein-2 (CRMP2), an important factor that is involved in the regulation of microtubule stability. OGT and SST attenuated not only increases in cortical GSK-3ß activity, but also the levels of phosphorylated CRMP2 in SAMP8. In vitro experiments, flavonoids contained in these kampo medicines, inhibited GSK-3ß activity in concentration-dependent manners. These results suggest that OGT and SST prevent aging-induced short-term working memory deficits by inhibiting aging-dependent elevations in the cortical GSK-3ß activity and subsequent CRMP2 phosphorylation.

Design and synthesis of functionalized coumarins as potential anti-austerity agents that eliminates cancer cells' tolerance to nutrition starvation.

Human pancreatic tumor cells have inherent ability to tolerate nutrition starvation which enables them to survive in the hypovascular tumor microenvironment. Discovery of agents that selectively inhibit the cancer cells' tolerance to nutrition starvation leading to cancer cell death is a new anti-austerity approach in anti-cancer drug discovery. A series of coumarins derivatives were synthesized and evaluated for their anti-austerity activity against PANC-1 human pancreatic cancer cell line. The compound 7-Hydroxy-2-oxo-2H-chromene-3-carboxylic acid (3-phenylpropyl)amide (2c) showed highly potent selective cytotoxicity against PANC-1 cells under nutrient-deprived conditions, with a PC50 value of 0.44 µM, without exhibiting toxicity in normal, nutrient-rich medium. Compound 2c caused dramatic alterations in PANC-1 cell morphology, leading to cell death. The compound 2c was found to inhibit PANC-1 cell migration and colony formation in a concentration-dependent manner. The compound 2c is a lead structure for the anti-austerity drug development against pancreatic cancer.

Kami-shoyo-san improves ASD-like behaviors caused by decreasing allopregnanolone biosynthesis in an SKF mouse model of autism.

Dysfunctions in the GABAergic system are associated with the pathogenesis of autism spectrum disorder (ASD). However, the mechanisms by which GABAergic system dysfunctions induce the pathophysiology of ASD remain unclear. We previously demonstrated that a selective type I 5α-reductase inhibitor SKF105111 (SKF) induced ASD-like behaviors, such as impaired sociability-related performance and repetitive grooming behaviors, in male mice. Moreover, the effects of SKF were caused by a decrease in the endogenous levels of allopregnanolone (ALLO), a positive allosteric modulator of the GABAA receptor. In this study, we used SKF-treated male mice as a putative animal model of ASD and examined the effects of Kami-shoyo-san (KSS) as an experimental therapeutic strategy for ASD. KSS is a traditional Kampo formula consisting of 10 different crude drugs and has been used for the treatment of neuropsychiatric symptoms. KSS dose-dependently attenuated sociability deficits and suppressed an increase in grooming behaviors in SKF-treated mice without affecting ALLO content in the prefrontal cortex. The systemic administration of the dopamine D1 receptor antagonist SCH23390 reversed the ameliorative effects of KSS. On the other hand, the dopamine D2 receptor antagonist sulpiride and GABAA receptor antagonist bicuculline only attenuated the ameliorative effect of KSS on repetitive self-grooming behaviors. The present results indicate that KSS improves SKF-induced ASD-like behaviors by facilitating dopamine receptor-mediated mechanisms and partly by neurosteroid-independent GABAA receptor-mediated neurotransmission. Therefore, KSS is a potential candidate for the treatment of ASD.

Ancistrolikokine E3, a 5,8'-Coupled Naphthylisoquinoline Alkaloid, Eliminates the Tolerance of Cancer Cells to Nutrition Starvation by Inhibition of the Akt/mTOR/Autophagy Signaling Pathway.

PANC-1 human pancreatic cancer cells are characterized by their ability to proliferate aggressively under hypovascular and hypoxic conditions in the tumor microenvironment, displaying a remarkable tolerance to nutrition starvation. The antiausterity strategy is a new approach in anticancer drug discovery aiming at the identification of potent agents that inhibit preferentially the survival of tumor cells during a limited supply of nutrients and oxygen. The new 5,8'-coupled naphthyldihydroisoquinoline alkaloid ancistrolikokine E3 (4), isolated from the Congolese liana Ancistrocladus likoko, showed potent preferential cytotoxicity against PANC-1 cells under nutrient-deprived conditions, with a PC50 value of 2.5 µM, without exhibiting toxicity in normal, nutrient-rich medium. The compound was found to induce dramatic alterations in cell morphology, leading to cell death. Moreover, it inhibited significantly PANC-1 cell migration and colony formation in a concentration-dependent manner. This study on 4 provides the first live evidence of the effect of a naphthyldihydroisoquinoline alkaloid against PANC-1 cells in nutrient-deprived medium. Mechanistic investigations conducted suggest that compound 4 is a potent inhibitor of the activation of the Akt/mTOR pathway. Furthermore, it inhibited the expression levels of the key autophagy regulators Atg5, Atg12, Beclin-1, LC3-I, and LC3-II. The results demonstrated that ancistrolikokine E3 (4) is a potent early-stage inhibitor of the autophagy pathway in PANC-1 human pancreatic cancer cells. Ancistrolikokine E3 (4) and related naphthylisoquinoline alkaloids are promising potential lead compounds for anticancer drug development based on the antiausterity strategy.

Ancistroyafungines A-D, 5,8'- and 5,1'-coupled naphthylisoquinoline alkaloids from a Congolese Ancistrocladus species, with antiausterity activities against human PANC-1 pancreatic cancer cells.

Four new naphthylisoquinoline alkaloids, the 5,8'-coupled ancistroyafungines A-C (1-3) and the 5,1'-linked ancistroyafungine D (4), have been isolated from the stem bark of an as yet unidentified Ancistrocladus (Ancistrocladaceae) liana recently discovered near the village Yafunga, in the North-Central region of the Democratic Republic of the Congo. Likewise obtained were eleven analogs previously identified in related African and Asian Ancistrocladus species, exhibiting five different coupling types, viz., 5,8', 5,1', 7,1', N,6', and N,8'. All of the alkaloids are S-configured at C-3 and possess an oxygen function at C-6 in the isoquinoline portion, and, thus, belong to the subclass of "Ancistrocladaceae-type" alkaloids. This finding is geo- and chemotaxonomically remarkable, since - apart from one other Ancistrocladus species from the Central Congo Basin - only Southeast Asian and East African Ancistrocladaceae are known to exclusively produce naphthylisoquinolines with these structural features. Moreover, the alkaloid pattern of this Congolese liana clearly demarcates this plant from all other Ancistrocladus taxa that have so far been botanically described, which suggests that it might represent a new species or subspecies. The new ancistroyafungines display strong preferential cytotoxic activities towards human PANC-1 pancreatic cancer cells in nutrient-deprived medium, without showing toxicity in normal, nutrient-rich conditions.

Discovery of potential antiausterity agents from the Japanese cypress Chamaecyparis obtusa.

The chloroform extract of the Japanese cypress Chamaecyparis obtusa was found to kill PANC-1 human pancreatic cancer cells preferentially in the nutrient-deprived medium without causing toxicity in the nutrient rich condition. Phytochemical investigation on this extract led to the isolation of a new sesquiterpene (1), together with the six sesquiterpenes (2-7) and a lignan (8). The isolated compounds were tested for their preferential cytotoxicity activity against five different human pancreatic cancer cell lines [PANC-1, MIA PaCa2, CAPAN-1, PSN-1, and KLM-1] by utilizing an antiausterity strategy. Among them, α-cadinol (2) was identified as the most active constituent. α-Cadinol (2) was found to inhibit the activation of Akt/mTOR pathway, and the hyperactivation of autophagy leading to preferential PANC-1 cell death during nutrient-starvation.

Constituents of the Rhizomes of Boesenbergia pandurata and Their Antiausterity Activities against the PANC-1 Human Pancreatic Cancer Line.

Human pancreatic cancer cell lines have a remarkable tolerance to nutrition starvation, which enables them to survive under a tumor microenvironment. The search for agents that preferentially inhibit the survival of cancer cells under low nutrient conditions represents a novel antiausterity strategy in anticancer drug discovery. In this investigation, a methanol extract of the rhizomes of Boesenbergia pandurata showed potent preferential cytotoxicity against PANC-1 human pancreatic cancer cells under nutrient-deprived conditions, with a PC50 value of 6.6 µg/mL. Phytochemical investigation of this extract led to the isolation of 15 compounds, including eight new cyclohexene chalcones (1-8). The structures of the new compounds were elucidated by NMR spectroscopic data analysis. Among the isolated compounds obtained, isopanduratin A1 (14) and nicolaioidesin C (15) exhibited potent preferential cytotoxicity against PANC-1 human pancreatic cancer cells under nutrition-deprived conditions, with PC50 values of 1.0 and 0.84 µM, respectively.

A New Cassane-type Diterpene from the Seed of Caesalpinia sappan.

Phytochemical investigation of the CH2Cl2 extract of the Vietnamese medicinal plant Caesalpinia sappan Linn resulted in the isolation of a new cassane-type diterpene named tomocin I (1). Its chemical structure was determined by NMR spectroscopic and mass spectrometric analysis.

Anti-austeritic Constituents of the Congolese Medicinal Plant Aframomum melegueta.

In the course of our search for anticancer agents based on a novel anti-austerity strategy, we found that the CHCl3 extract of the roots of Aflamomum melegueta (Zingiberaceae), collected in the Democratic Republic of Congo, killed PANC-1 human pancreatic cancer cells preferentially in nutrient-deprived medium (NDM). Phytochemical investigation of the CHCl3 extract led to the isolation of seven known compounds [(-)-buplerol (1), (-)-arctigenin (2), (E)-14-hydroxy-15-norlabda-8(17),12-dien-16-al (3), labda-8(17),12-dien-15,16-dial (4), 16-oxo-8(17),12(E)-labdadien-15-oic acid (5), 5-hydroxy-7-methoxyflavone (6), and apigenin (7)]. In addition to the previously reported preferentially cytotoxic compound, (-)-arctigenin (2, PC50 0.5 µM), (-)-buplerol (1) also displayed potent preferential cytotoxicity with a PC50 value of 8.42 µM and triggered apoptosis-like PANC-1 cell death in NDM.

A new polyoxygenated cyclohexane and other constituents from Kaempferia rotunda and their cytotoxic activity.

The isolation of secondary metabolites from a methanolic extract of Kaempferia rotunda yielded 12 compounds (1-12), including a new polyoxygenated cyclohexane compound, (-)-3-acetyl-4-benzoyl-1-benzoyloxymethyl-1,6-diepoxycyclohexan-2,3,4,5-tetrol (1). The structures of the isolated compounds were determined based on their spectroscopic data and comparison with references. All of the isolated compounds were tested for their cytotoxic activity against pancreatic (PSN-1) and breast (MDA-MB231) cancer cell lines. Compound 12 showed moderate cytotoxic activity against PSN-1 and MDA-MB231 without showing any cytotoxicity against the normal cell line, TIG-3.

Two new diphenylmethyl-substituted xanthones from Seicuridaca longepedunculata.

Two new diphenylmethyl-substituted xanthones, named muchimangins K (1) and L (2), have been isolated from the roots of Securidaca longepedunculata (Polygalaceae) collected in the Democratic Republic of Congo. Their structures were established by analyses of the spectral data, including 2D NMR spectra, to be 1 ,3,6,8-tetrahydroxy-2.5-dimethoxy-4-[ -(2,4,5-trimethoxyphenyl)-1-phenylmethyl]xanthone (1) and 1,3,6-trihydroxy-4,7-dimethoxy-2-[1-(2,4,5-trimethoxyphenyl)- 1-phenylmethyl]xanthone (2).

Antiausterity activity of arctigenin enantiomers: importance of (2R,3R)-absolute configuration.

From a MeOH extract of powdered roots of Wikstroemia indica, six dibenzyl-gamma-butyrolactone-type lignans with (2S,3S)-absolute configuration [(+)-arctigenin (1), (+)-matairesinol (2), (+)-trachelogenin (3), (+)-nortrachelogenin (4), (+)-hinokinin (5), and (+)-kusunokinin (6)] were isolated, whereas three dibenzyl-gamma-butyrolactone-type lignans with (2R,3R)-absolute configuration [(-)-arctigenin (1*), (-)-matairesinol (2*), (-)-trachelogenin (3*)] were isolated from Trachelospermum asiaticum. The in vitro preferential cytotoxic activity of the nine compounds was evaluated against human pancreatic PANC-1 cancer cells in nutrient-deprived medium (NDM), but none of the six lignans (1-6) with (2S,3S)-absolute configuration showed preferential cytotoxicity. On the other hand, three lignans (1*-3*) with (2R,3R)-absolute configuration exhibited preferential cytotoxicity in a concentration-dependent manner with PC50 values of 0.54, 6.82, and 5.85 microM, respectively. Furthermore, the effect of (-)- and (+)-arctigenin was evaluated against the activation of Akt, which is a key process in the tolerance to nutrition starvation. Interestingly, only (-)-arctigenin (1*) strongly suppressed the activation of Akt. These results indicate that the (2R,3R)-absolute configuration of (-)-enantiomers should be required for the preferential cytotoxicity through the inhibition of Akt activation.

Heptaoxygenated xanthones as anti-austerity agents from Securidaca longepedunculata.

In a course of our search for anticancer agent based on a novel anti-austerity strategy, we found that the CHCl3 extract of the roots of Securidaca longepedunculata (Polygalaceae), collected at Democratic Republic of Congo, killed PANC-1 human pancreatic cancer cells preferentially in nutrient-deprived medium (NDM). Phytochemical investigation on the CHCl3 extract led to the isolation of 28 compounds including five new polymethoxylated xanthones [1,6,8-trihydroxy-2,3,4,5-tetramethoxyxanthone (1), 1,6-dihydroxy-2,3,4,5,8-pentamethoxyxanthone (2), 8-hydroxy-1,4,5,6-tetramethoxy-2,3-methylenedioxyxanthone (3), 4,6,8-trihydroxy-1,2,3,5-tetramethoxyxanthone (4), 4,8-dihydroxy-1,2,3,5,6-pentamethoxyxanthone (5)] and a new benzyl benzoate [benzyl 3-hydroxy-2-methoxybenzoate (6)]. Among them, 1,6,8-trihydroxy-2,3,4,5-tetramethoxyxanthone (1) and 1,6-dihydroxy-2,3,4,5,8-pentamethoxyxanthone (2) displayed the potent preferential cytotoxicity with PC50 of 22.8 and 17.4 µM, respectively. They triggered apoptosis-like PANC-1 cell death in NDM with a glucose-sensitive mode.