Curcuminoids supplementation ameliorates iron overload, oxidative stress, hypercoagulability, and inflammation in non-transfusion-dependent ß-thalassemia/Hb E patients.

Curcuminoids, polyphenol compounds in turmeric, possess several pharmacological properties including antioxidant, iron-chelating, and anti-inflammatory activities. Effects of curcuminoids in thalassemia patients have been explored in a limited number of studies using different doses of curcuminoids. The present study aims to evaluate the effects of 24-week curcuminoids supplementation at the dosage of 500 and 1000 mg/day on iron overload, oxidative stress, hypercoagulability, and inflammation in non-transfused ß-thalassemia/Hb E patients. In general, both curcuminoids dosages significantly lowered the levels of oxidative stress, hypercoagulability, and inflammatory markers in the patients. In contrast, reductions in iron parameter levels were more remarkable in the 1000 mg/day group. Subgroup analysis revealed that a marker of hypercoagulability was significantly decreased only in patients with baseline ferritin ≤ 1000 ng/ml independently of curcuminoids dosage. Moreover, the alleviation of iron loading parameters was more remarkable in patients with baseline ferritin > 1000 ng/ml who receive 1000 mg/day curcuminoids. On the other hand, the responses of oxidative stress markers were higher with 500 mg/day curcuminoids regardless of baseline ferritin levels. Our study suggests that baseline ferritin levels should be considered in the supplementation of curcuminoids and the appropriate curcuminoids dosage might differ according to the required therapeutic effect. Thai Clinical Trials Registry (TCTR): TCTR20200731003; July 31, 2020 "retrospectively registered".

Anti-inflammatory and Antioxidant Activity of Nanoencapsulated Curcuminoids Extracted from Curcuma longa L. in a Model of Cutaneous Inflammation.

The present study evaluated the anti-inflammatory effect of nanoencapsulated curcuminoid preparations of poly(vinyl pyrrolidone) (Nano-cur) and free curcuminoids (Cur) in an experimental model of croton oil-induced cutaneous inflammation. Male Swiss mice, weighing 25-30 g, received oral treatment by gavage 1 h before CO application or topical treatment immediately after CO application (200 µg diluted in 70% acetone) with a single dose of Cur and Nano-cur. After 6 h, the animals were anesthetized and euthanized. The ears were sectioned into disks (6.0 mm diameter) and used to determine edema, myeloperoxidase (MPO) activity, and oxidative stress. Photoacoustic spectroscopy (PAS) was used to evaluate the percutaneous penetration of Cur and Nano-cur. Topical treatment with both preparations had a similar inhibitory effect on the development of edema, MPO activity, and the oxidative response. The PAS technique showed that the percutaneous permeation of both topically applied preparations was similar. Oral Nano-cur administration exerted a higher anti-inflammatory effect than Cur. Topical Cur and Nano-cur application at the same dose similarly inhibited the inflammatory and oxidative responses. Oral Nano-cur administration inhibited such responses at doses that were eight times lower than Cur, suggesting the better bioavailability of Nano-cur compared with Cur.Graphical abstract.

Effects of supplementation with curcuminoids on serum adipokines in critically ill patients: a randomized double-blind placebo-controlled trial.

Previous studies have shown a beneficial effect of curcuminoids supplementation on serum concentrations of adipokines; however, there are no published studies that have examined this effect among critically ill patients. We aimed to assess the effects of supplementation with curcuminoids on serum concentrations of leptin and adiponectin in critically ill patients with traumatic brain injury (TBI). In this trial, 62 critically ill patients with TBI, aged 18-65 years, were randomly allocated to receive either 500 mg/day curcuminoids (co-administered with 5 mg/day piperine) or matched placebo for 7 days. Patients in both intervention groups received routine treatments for TBI as well as enteral nutrition. Serum concentrations of leptin and adiponectin were measured at baseline and at the end of trial. We found a significant reduction in serum levels of leptin in both curcuminoids (47.1%) and placebo (22.8%) groups; though the magnitude of reduction was greater in the former (p < .05). Supplementation with curcumioinds was not found to alter serum concentrations of adiponectin (p > .05). Supplementation with curcumioinds significantly reduced serum levels of leptin but had no significant effect on adiponectin levels in critically ill patients with TBI. Further clinical trials, particularly those with a long-term period, are needed to confirm our findings.

Novel Combinatorial Regimen of Garcinol and Curcuminoids for Non-alcoholic Steatohepatitis (NASH) in Mice.

Non-alcoholic steatohepatitis (NASH) is a progressive form of Non-alcoholic fatty liver disease (NAFLD), a chronic liver disease with a significant unmet clinical need. In this study, we examined the protective effects of Garcinia indica extract standardized to contain 20% w/w of Garcinol (GIE) and 95% Curcuminoids w/w from Curcuma longa (Curcuminoids) in a Stelic animal model (STAM) of NASH. The STAM mice developed steatosis, hepatocyte ballooning, and inflammation, which were significantly reduced by the combination of GIE and Curcuminoids, resulting in a lower NAFLD activity score. The treatment reduced fibrosis as observed by Sirius red staining, liver hydroxyproline content and mRNA levels of TGF- ß and collagen in the liver. Immunostaining with alpha-smooth muscle actin (α SMA) revealed a significant reduction in hepatic stellate cells. Intriguingly, the combination regimen markedly decreased the mRNA levels of MCP1 and CRP and both mRNA and protein levels of TNF-α. NF-kB, reduced the hepatic and circulating FGF21 levels and altered the nonenzymatic (glutathione) and enzymatic antioxidant markers (Glutathione peroxidase, and superoxide dismutase). Our results suggest that the combination of GIE and Curcuminoids can reduce the severity of NASH by reducing steatosis, fibrosis, oxidative stress, and inflammation. The results suggest that the combinatorial regimen could be an effective supplement to prevent the progression of liver steatosis to inflammation and fibrosis in NASH.

Curcuminoids encapsulated liposome nanoparticles as a blue light emitting diode induced photodynamic therapeutic system for cancer treatment.

Unlike normal cells, cancer cells mutate to thrive in exaggerated levels of reactive oxygen species (ROS). This potentially makes them more susceptible to small molecule-induced oxidative stress. The intracellular ROS increase in cancer cells is a potential area under investigation for the development of cancer therapeutics targeting cancer cells. Visible photons of 430-490 nm wavelengths from a blue-light emitting diode (BLED) encompass the visible region of the spectrum known to induce ROS in cancer cells. Curcuminoids (CUR) naturally occurring photosensitizers sensitized by the blue wavelength of the visible light, well known for its potent anti-inflammatory and anticancer activity. Poor solubility and bioavailability, of the compound of the small molecule CUR restrict the therapeutic potential and limits CUR to be used as a photosensitizer. Here, our research group reports the use of small molecules CUR, encapsulated in liposome nanocarriers (LIP-CUR) coupled with blue light-emitting diode (BLED) induced photodynamic therapy (BLED-PDT). In A549 cancer cells in vitro, LIP-CUR coupled with BLED initiated BLED-PDT and triggered 1O2, ultimately resulting in caspase-3 activated apoptotic cell death. The combination of a non-cytotoxic dose of small molecule CUR co-treated with BLED to trigger BLED-PDT could be translated and be developed as a novel strategy for the treatment of cancer.

Combined treatment of AT101 and demethoxycurcumin yields an enhanced anti-proliferative effect in human primary glioblastoma cells.

PURPOSE: Glioblastoma multiforme (GBM) is a poorly curable disease due to its profound chemoresistance. Despite recent advances in surgery, radiotherapy and chemotherapy, the efficient treatment of GBMs is still a clinical challenge. Beside others, AT101, the R-(-) enantiomer of gossypol, and demethoxycurcumin (DMC), a curcumin-related demethoxy compound derived from Curcuma longa, were considered as possible alternative drugs for GBM therapy. METHODS: Using different human primary GBM cell cultures in a long-term stimulation in vitro model, the cytotoxic and anti-proliferative effects of single and combined treatment with 5 µM AT101 and 5 µM or 10 µM DMC were investigated. Furthermore, western blots on pAkt and pp44/42 as well as JC-1 staining and real-time RT-PCR were performed to understand the influence of the treatment at the molecular and gene level. RESULTS: Due to enhanced anti-proliferative effects, we showed that combined therapy with both drugs was superior to a single treatment with AT101 or DMC. Here, by determination of the combination index, a synergism of the combined drugs was detectable. Phosphorylation and thereby activation of the kinases p44/42 and Akt, which are involved in proliferation and survival processes, were inhibited, the mitochondrial membrane potential of the GBM cells was altered, and genes involved in dormancy-associated processes were regulated by the combined treatment strategy. CONCLUSION: Combined treatment with different drugs might be an option to efficiently overcome chemoresistance of GBM cells in a long-term treatment strategy.

Curcuminoids plus piperine improve nonalcoholic fatty liver disease: A clinical trial.

BACKGROUND: Nonalcoholic fatty liver disease (NAFLD) as a prevalent hepatic disease is associated with an increased risk of morbidity and mortality related to the liver and cardiovascular disease (CVD). Lifestyle modification and good metabolic control is the first line of treatment, but not always efficacious in reversing NAFLD pathogenesis. Curcumin is a dietary phytochemical with hepatoprotective activities, though its low bioavailability is considered as a major challenge for clinical applications. Therefore, in this study, in order to improve the bioavailability of curcumin, it was coadministered with piperine and we investigated the effects of this bioavailability-enhanced curcumin on serum hepatic enzymes, lipid profile, and glycemic indices in patients with NAFLD. METHODS: In this randomized controlled parallel-group trial, 70 subjects with ultrasound-determined NAFLD were randomized to either 500 mg curcuminoids coadministered with 5 mg piperine daily or placebo for 12 weeks. NAFLD severity (on the basis of sonography) and hepatic function was assessed at baseline and at the study end. RESULTS: Seventy subjects completed the study. Supplementation with curcuminoids plus piperine significantly reduced the hematocrit (P = 0.027), erythrocyte sedimentation rate (P = 0.048) and the serum concentrations of alanine aminotransferase (P = 0.035), aspartate aminotransferase (P = 0.042), alkaline phosphatase (P = 0.004), cholesterol (P < 0.016), low-density lipoprotein cholesterol (P < 0.017), Iron (P = 0.026), and Hemoglobin (P = 0.025) and increased total iron-binding capacity (P = 0.003). However, except albumin, changes in other parameters were not statistically different between groups. In addition, administration of curcuminoids plus piperine significantly improved NAFLD severity (P < 0.001), which was statistically different compared with the placebo group (P = 0.022). Also, the percentage of improved patients was marginally higher in the curcuminoids plus piperine group when compared with the placebo group (P = 0.058). CONCLUSION: This study suggested beneficial effects of combined curcuminoids and piperine supplementation on disease severity in patients with NAFLD.

A Systematic Review and Meta-analysis of Randomized Controlled Trials on the Effects of Turmeric and Curcuminoids on Blood Lipids in Adults with Metabolic Diseases.

Dyslipidemia is a global health problem and a high risk factor for atherosclerosis, which can lead to serious cardiovascular disease (CVD). Existing studies have shown inconsistent effects of turmeric and curcuminoids on blood lipids in adults. We performed this systematic review and meta-analysis to evaluate the effects of turmeric and curcuminoids on blood triglycerides (TG), total cholesterol (TC), LDL cholesterol, and HDL cholesterol. We searched the English databases of the Web of Science, PubMed, Ovid (including EMBASE and MEDLINE), Scopus, and the Cochrane Library and 2 Chinese databases, Wanfang Data and China National Knowledge Infrastructure, for randomized controlled trials (RCTs) that studied the effects of turmeric and curcuminoids on blood TG, TC, LDL cholesterol, and HDL cholesterol in subjects with metabolic diseases. With random-effects models, separate meta-analyses were conducted by using inverse-variance. The results are presented as the mean difference with 95% CIs. Evidence from 12 RCTs for TG, 14 RCTs for TC, 13 RCTs for LDL cholesterol, and 16 RCTs for HDL cholesterol showed that turmeric and curcuminoids could lower blood TG by -19.1 mg/dL (95% CI: -31.7, -6.46 mg/dL; P = 0.003), TC by -11.4 mg/dL (95% CI: -17.1, -5.74 mg/dL; P < 0.0001), and LDL cholesterol by -9.83 mg/dL (95% CI: -15.9, -3.74 mg/dL; P = 0.002), and increase HDL cholesterol by 1.9 mg/dL (95% CI: 0.31, 3.49 mg/dL; P = 0.02). In conclusion, turmeric and curcuminoids can significantly modulate blood lipids in adults with metabolic diseases. However, these findings should be interpreted cautiously because of the significant heterogeneity between included studies (I2 > 50%). There is a need for further RCTs in future.

Effects of Curcuminoids on Myocardial Injury After Percutaneous Coronary Intervention.

The rise of cardiac troponin post-percutaneous coronary intervention (PCI) is associated with a high risk of long-term cardiovascular events. Previous studies have shown that curcuminoids decreased myocardial injury post-coronary bypass graft surgery through anti-oxidant and anti-inflammatory effects. We sought to examine whether curcuminoids could prevent PCI-related myocardial injury. One-hundred enrolled patients receiving elective PCI were randomized to obtain curcuminoids or placebo 4 g/day at least 1 day before and after the scheduled PCI. Cardiac troponin-T and 12-lead electrocardiogram were evaluated before PCI and at 24 and 48 h post-PCI. The definitions of PCI-related myocardial injury and myocardial infarction were in line with the third universal definition of myocardial infarction. Baseline characteristics of patients and procedures did not differ between the curcuminoids and placebo groups. The mean age was 63.9 ± 10.8 years. The incidence of PCI-related myocardial injury was not different between curcuminoids and placebo groups (32% vs. 38%, P = .675). The peak high-sensitive cardiac troponin T levels after PCI were not different between the curcuminoids and placebo groups (201.0 ± 547.0 ng/L vs. 187.0 ± 703.9 ng/L respectively, P = .912). Further, the high-sensitive C-reactive protein levels post-PCI were similar in patients receiving curcuminoids and placebo (7.2 ± 18.8 mg/dL vs. 6.6 ± 17.5 mg/dL, respectively, P = .873). We found that short-term treatment with curcuminoids did not reduce the occurrence of PCI-related myocardial injury. We did not observe the role of anti-oxidative and anti-inflammatory effects of curcuminoids in the PCI-related myocardial injury.

PHMH, a diarylheptanoid from Alpinia officinarum attenuates VEGF-induced angiogenesis via inhibition of the VEGFR-2 signaling pathway.

The rhizome of Alpinia officinarum Hance, a popular spice used as a condiment in China and Europe, has various reported bioactivities, including anticancer, anti-inflammatory and antioxidant effects. However, its anti-angiogenic activity has not previously been reported. In this study, a diarylheptanoid was isolated from Alpinia officinarum and identified as 1-phenyl-7-(4-hydroxy-3-methoxyphenyl)-4E-en-3-heptanone (PHMH). We demonstrated that PHMH exerts anti-angiogenic activity both in vitro and in vivo. PHMH inhibited vascular endothelial growth factor (VEGF)-induced viability, migration, invasion and tube formation in human umbilical vein endothelial cells (HUVECs) in vitro, and also suppressed VEGF-induced sprout formation of rat aorta ex vivo. Furthermore, PHMH was found to block VEGF-induced vessel formation in mice and suppress angiogenesis in both zebrafish and chorioallantoic membrane models. Mechanistic studies indicated that PHMH inhibited VEGF-induced VEGF receptor-2 (VEGFR-2) auto-phosphorylation and resulted in the blockage of VEGFR-2-mediated signaling cascades in HUVECs, including the Akt/mTOR, ERK1/2, and FAK pathways. Our findings provide new insights into the potential application of PHMH as a therapeutic agent for anti-angiogenesis.

Selective Estrogen Receptor Modulator (SERM)-like Activities of Diarylheptanoid, a Phytoestrogen from Curcuma comosa, in Breast Cancer Cells, Pre-osteoblast Cells, and Rat Uterine Tissues.

Diarylheptanoids from Curcuma comosa, of the Zingiberaceae family, exhibit diverse estrogenic activities. In this study we investigated the estrogenic activity of a major hydroxyl diarylheptanoid, 7-(3,4 -dihydroxyphenyl)-5-hydroxy-1-phenyl-(1E)-1-heptene (compound 092) isolated from C. comosa. The compound elicited different transcriptional activities of estrogen agonist at low concentrations (0.1-1 µM) and antagonist at high concentrations (10-50 µM) using luciferase reporter gene assay in HEK-293T cells. In human breast cancer (MCF-7) cells, compound 092 showed an anti-estrogenic activity by down-regulating ERα-signaling and suppressing estrogen-responsive genes, whereas it attenuated the uterotrophic effect of estrogen in immature ovariectomized rats. Of note, compound 092 promoted mouse pre-osteoblastic (MC3T3-E1) cell differentiation and the related bone markers, indicating its positive osteogenic effect. Our findings highlight a new, nonsteroidal, estrogen agonist/antagonist of catechol diarylheptanoid from C. comosa, which is scientific evidence supporting its potential as a dietary supplement to prevent bone loss with low risk of breast and uterine cancers in postmenopausal women.

Preparative Purification of Anti-Proliferative Diarylheptanoids from Betula platyphylla by High-Speed Counter-Current Chromatography.

A simple and rapid method using high-speed counter-current chromatography (HSCCC), along with bioassay-guided fractionation based on the anti-proliferative activity against renal and colon cancer cells, has been developed for the preparative separation of aceroside VIII (1) and platyphylloside (2) from Betula platyphylla. A solvent system composed of ethyl acetate/acetonitrile/water (1:0.1:1, v/v/v) was optimized for the separation. The upper phase was used as the stationary phase, and the lower phase was used as the mobile phase. Among these isolated diarylheptanoids, platyphylloside (2) showed anti-proliferative activity in the COLO205 and KM12 colon cells and renal cancer cell lines A498, U031, as well as in MG63 and MG 63.3 osteosarcoma cells. In addition, it showed dose dependent inhibitory effects in the NCI 60 cell line assay. These results suggest that the diarylheptanoids isolated from B. platyphylla with an efficient HSCCC method could be potential multi-targeted therapeutic agents for cancer.

Diarylheptanoids from Alnus nepalensis attenuates LPS-induced inflammation in macrophages and endotoxic shock in mice.

Diarylheptanoids, a group of plant secondary metabolites are increasingly recognized as potential therapeutic agents. The aim of study was to ascertain the anti-inflammatory profile of diarylheptanoids from Alnus nepalensis against lipopolysaccharide (LPS)-induced inflammation in macrophages and endotoxic shock in mice. Extracts prepared from dried leaves of A. nepalensis using standard solvents were tested against LPS-induced inflammation in macrophages. Among all, butanol extract (ANB) has shown most significant inhibition of pro-inflammatory cytokines without any cytotoxicity. HPLC analysis of ANB showed the presence of diarylheptanoids. The diarylheptanoids were further isolated and tested in-vitro for anti-inflammatory activity. Treatment of isolated diarylheptanoids (HOG, ORE and PLS) was able to reduce the production and mRNA level of pro-inflammatory cytokines (TNF-α and IL-6). Furthermore, we demonstrated that it inhibited the expression of NF-kB protein in LPS-induced inflammation in macrophages. In-vivo efficacy and safety profile of ANB revealed that oral treatment of ANB was able to improve the survival rate, and inhibited the production of pro-inflammatory cytokines in serum, attenuated vital organ injury in a dose dependent manner without any toxic effect at higher dose in mice. The results suggest that diarylheptanoids from A. nepalensis can be considered as potential therapeutic candidates for the management of inflammation related diseases.

Diarylheptanoid compounds from Alnus nepalensis express in vitro and in vivo antifilarial activity.

A large number of medicinal plants remain to be explored for antifilarial compounds. In the present study a crude methanolic extract of leaves of Alnus nepalensis, chloroform- and n-butanol-partitioned fractions from the crude extract and 6 bioactivity-guided isolated compounds including two new diarylheptanoid from the fractions were assayed for microfilaricidal, macrofilaricidal and female worm sterilizing activity using the lymphatic filariid Brugia malayi in in vitro and in vivo systems. In vitro, the crude methanolic extract exerted better microfilaricidal (LC100: 15.63µg/ml, IC50: 6.00µg/ml) than macrofilaricidal (LC100: >250; IC50: 88µg/ml) activity whereas chloroform and n-butanol fractions were more macrofilaricidal (LC100: 125 and 31.25µg/ml; IC50: 13.14 and 11.84, respectively) than microfilaricidal (LC100: 250-500µg/ml, IC50: 44.16µg/ml). In addition, n-butanol fraction also caused 74% inhibition in MTT reduction potential of the adult worms. In vivo (doses: crude: 100-200mg/kg; fractions: 100mg/kg, i.p.×5 days) the chloroform fraction exerted >50% macrofilaricidal activity whereas methanolic extract and n-butanol fraction produced 38-40% macrofilaricidal action along with some female sterilizing efficacy. Of the 5 diarylheptanoid compounds isolated, alnus dimer, and (5S)-5-hydroxy-1-(4-hydroxyphenyl)-7-(3,4-dihydroxyphenyl)-3-heptanone were found to show the most potent with both macrofilaricidal (LC100: 15.63µg/ml, IC50: 6.57-10.31µg/ml) and microfilaricidal (LC100: 31.25-62.5µg/ml, IC50: 11.05-22.10µg/ml) activity in vitro. These findings indicate that the active diarylheptanoid compounds may provide valuable lead for design and development of new antifilarial agent(s).

Antiviral activities of diarylheptanoids against influenza virus in vitro.

The anti-influenza A/PR/8/34 (H1N1) virus activities of ten diarylheptanoids isolated from Alpinia officinarum were examined using the MTT method. The 50% inhibitory concentration of each diarylheptanoid examined was clearly lower than its 50% cytotoxic concentration determined by the MTT assay and/or maximum non-cytotoxic concentration (MNCC) determined by the morphological change of cells. In particular, the influenza virus was more susceptible to 7-(4''-hydroxy-3''-methoxyphenyl)-1-phenyl-4E-hepten-3-one (3) and (5S)-5-hydroxy-7-(4''-hydroxyphenyl)-1-phenyl-3-heptanone (8) than the other diarylheptanoids. Thus, all diarylheptanoids exhibited potential antiviral activity against influenza virus in vitro.

Effect of topical application and intraperitoneal injection of oregonin on atopic dermatitis in NC/Nga mice.

The diarylheptanoid, oregonin (ORE), which was isolated from the bark of Alnus japonica Steudel that grows natively in Korea, has been known to exert antioxidative, anti-inflammatory, anti-cancer and immune response inhibitory effects. The antioxidative effect of ORE was observed on the superoxide and 1,1-diphenyl-2-picrylhydrazyl radical, as well as on the expression of inducible nitric oxide synthase and cyclooxygenase-2 in lipopolysaccharide-treated RAW264.7 macrophages. The statistically significant inhibitory action of ORE against production of cytokines induced by bacterial products or by interleukin (IL)-1beta, free radicals and nitrogen species, and a corresponding increase in cellular calcium concentration because of ORE were confirmed in bone marrow and spleen dendritic cells that are known to play important functions in the development and advancement of atopic dermatitis (AD). It was thus expected that ORE would exert a beneficial effect in the treatment of AD. A study on the pharmaceutical benefits of ORE against AD has not yet been conducted in vivo. We therefore used an in vivo AD animal model, namely the NC/Nga mice, and by applying ORE onto the animals through skin application as well as intraperitoneal injection, we attempted to evaluate the benefits of ORE in this system. Evaluation of ORE was conducted by following the SCORE method to score the effect, as well as by measuring the Th2 cytokines IL-4, IL-5 and IL-13 levels from serum and lymphocytes, and IgE and eosinophil levels from serum. Additionally, the expression of mRNA and protein levels was estimated using real-time polymerase chain reaction and Western blotting analysis. The following categories of clinical evaluation, Th2 cytokines IL-4, IL-5 and IL-13 values, serum IgE levels, serum eosinophil levels, and mRNA and protein expression levels of iNOS and COX-2, were evaluated from topical application and intraperitoneal injection groups of ORE. The effects of ORE on AD in NC/Nga mice were confirmed as being similar to the positive control group, while a significant difference with the negative control group was observed. The results presented in this report suggest that ORE might be beneficial in the treatment of AD.

Determination of a novel diarylheptanoid (Juglanin B) from green walnut husks (Juglans regia L.) in rat plasma by high-performance liquid chromatography.

A simple and reliable analytical method based on high-performance liquid chromatography (HPLC) coupled with a diode array detector (DAD) was developed for the determination of a novel diarylheptanoid (Juglanin B) from green walnut husks (Juglans regia L.) in rat plasma using rhoiptelol as an internal standard. Chromatographic separation was carried out on a Sinochrom ODS-AP C(18) column (250 x 4.6 microm i.d., 5 mm) with acetonitrile-10 mM postassium dihydrogen phosphate (pH = 3; 55:45, v/v) as mobile phase, and the detection wavelength was set at 214 nm. The plasma samples were prepared using methanol as protein precipitator. The extraction recovery of Juglanin B ranged from 70.26 to 78.59%, and the calibration curve had a good linearity in the range 0.08-50 microg/mL (r(2) = 0.9932). The RSDs of intra- and inter-day precision ranged from 1.19 to 4.92% and 4.35 to 4.54%, respectively. The HPLC-DAD method described is a simple, rapid and reliable method for the determination of Juglanin B level and for use in studies involving pharmacokinetics.

Inhibitory effect of the rhizomes of Alpinia officinarum on TPA-induced inflammation and tumor promotion in two-stage carcinogenesis in mouse skin.

The methanol extract of galangal (the rhizomes of Alpinia officinarum L.) exhibited remarkable antitumor-promoting activity on an in vivo two-stage carcinogenesis test of mice using 7,12-dimethylbenz[a]anthracene as an initiator and 12-O-tetradecanoylphorbol-13-acetate (TPA) as a promoter. Seven diarylheptanoids (1-7) were isolated and identified from the active fraction of the methanol extracts of the galangal. These compounds, 1-7, were evaluated for their inhibitory effects on TPA-induced inflammation (1 microg/ear) in mice. These compounds (1-7) tested showed marked anti-inflammatory effects, with a 50% inhibitory dose of 0.8-2.7 micromol/ear.

Inhibitory activity of diarylheptanoids on farnesyl protein transferase.

Diarylheptanoids [curcumin (1), demethoxycurcumin (2), bisdemethoxycurcumin (3), bisdimethoxymethylcurcumin (4), and 1,2-dihydrobis(de-O-methyl)curcumin (5)] were isolated from the methanolic extract of Curcuma longa L. and a new cyclic diarylheptanoid (6) and a known Compound 7 were isolated from fruits of Alnus japonica Steud. Diarylheptanoids (1-3) inhibited farnesyl protein transferase (FPTase) with an IC50 of 29-50 microM. The other compounds very mildly inhibited FPTase, therefore, the inhibitory activity on FPTase very much depends on the structure of diarylheptanoids.

New diarylheptanoids from the rhizomes of Dioscorea spongiosa and their antiosteoporotic activity.

Bioassay-guided fractionation of the water extract of the rhizomes of Dioscorea spongiosa led to the isolation and identification of new diarylheptanoids, diospongins A - C, together with three known lignans. Their structures, including absolute stereochemistry, were determined by analyses of NMR data, chemical conversions and CD spectrum. The isolated compounds, except for diospongin A, exerted potent inhibitory activities on bone resorption induced by parathyroid hormone in a bone organ culture system.