Practical Synthesis of Chalcone Derivatives and Their Biological Activities.

Practical synthesis and biological activities of 4-hydroxy-3-methoxy-2-propene derivatives are described. The novel chalcone derivatives were prepared by acid catalysed one-step condensation of 1,3- or 1,4-diacetylbenzene and 1,3,5-triacetylbenzene with 4-hydroxy-3-methoxybenzaldehyde. They were then evaluated for free radical scavenging activity, suppression of lipopolysaccharides (LPS)-induced NO generation, and anti-excitotoxicity in vitro. It was found that all compounds showed good effects for 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging, LPS-induced NO generation, and anti-neurotoxicity. Compounds 6 and 7 were potent suppressor of NO generation with the concentration range 10 µM and especially compound 8 showed very potent anti-inflammatory activity with 1 µM. In addition, the di- and tri-acetylbenzyl derivatives 6, 7, and 8 showed enhanced anti-neurotoxicity activity in cultured cortical neurons. Molecular modelling studies to investigate the chemical structural characteristics required for the enhanced biological activities interestingly revealed that compound 8 has the smallest highest occupied molecular orbital-lowest energy unoccupied molecular orbital (HOMO-LUMO) gap, which signifies easy electron and radical transfer between HOMO and LUMO in model studies.

Hepatoprotective effect of licorice, the root of Glycyrrhiza uralensis Fischer, in alcohol-induced fatty liver disease.

BACKGROUND: Our previous study suggested that licorice has anti-inflammatory activity in lipopolysaccharide-stimulated microglial cells and anti-oxidative activity in tert-butyl hydroperoxide-induced oxidative liver damage. In this study, we evaluated the effect of licorice on chronic alcohol-induced fatty liver injury mediated by inflammation and oxidative stress. METHODS: Raw licorice was extracted, and quantitative and qualitative analysis of its components was performed by using LC-MS/MS. Mice were fed a liquid alcohol diet with or without licorice for 4 weeks. RESULTS: We have standardized 70% fermented ethanol extracted licorice and confirmed by LC-MS/MS as glycyrrhizic acid (GA), 15.77 ± 0.34 µg/mg; liquiritin (LQ), 14.55 ± 0.42 µg/mg; and liquiritigenin (LG), 1.34 ± 0.02 µg/mg, respectively. Alcohol consumption increased serum alanine aminotransferase and aspartate aminotransferase activities and the levels of triglycerides and tumor necrosis factor (TNF)-α. Lipid accumulation in the liver was also markedly induced, whereas the glutathione level was reduced. All these alcohol-induced changes were effectively inhibited by licorice treatment. In particular, the hepatic glutathione level was restored and alcohol-induced TNF-α production was significantly inhibited by licorice. CONCLUSION: Taken together, our data suggests that protective effect of licorice against alcohol-induced liver injury may be attributed to its anti-inflammatory activity and enhancement of antioxidant defense.

Anti-tumor activity of benzylideneacetophenone derivatives via proteasomal inhibition in prostate cancer cells.

A number of some chalcone derivatives possess promising biological properties including anti-inflammation, anti-oxidant, and anti-tumor activity. Although it has been shown that some derivatives of chalcone induce apoptosis in different kinds of cancer cells, the involved mechanism of action is not well defined. The purpose of this study is to investigate the primary target of a benzylideneacetophenone derivative (JC3), which is a synthetic compound derived from the chalcone family, in human cancer, using prostate cancer cells as a working model. Herein, we show that JC3 inhibits proteasomal activity as indicated by both in vitro and in cell-based assays. Especially, the JC3-dimer was more potent than monomer in the aspect of proteasome inhibition, which induced apoptosis significantly in the prostate cancer cells. Owing to the critical roles of the proteasome in the biology of human tumor progression, invasion, and metastasis, these findings give an important clue for the development of novel anti-tumor agents.

Anti-Inflammatory activities of licorice extract and its active compounds, glycyrrhizic acid, liquiritin and liquiritigenin, in BV2 cells and mice liver.

This study provides the scientific basis for the anti-inflammatory effects of licorice extract in a t-BHP (tert-butyl hydrogen peroxide)-induced liver damage model and the effects of its ingredients, glycyrrhizic acid (GA), liquiritin (LQ) and liquiritigenin (LG), in a lipopolysaccharide (LPS)-stimulated microglial cell model. The GA, LQ and LG inhibited the LPS-stimulated elevation of pro-inflammatory mediators, such as inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), tumor necrosis factor (TNF)-alpha, interleukin (IL)-1beta and interleukin (IL)-6 in BV2 (mouse brain microglia) cells. Furthermore, licorice extract inhibited the expression levels of pro-inflammatory cytokines (TNF-α, IL-1ß and IL-6) in the livers of t-BHP-treated mice models. This result suggested that mechanistic-based evidence substantiating the traditional claims of licorice extract and its three bioactive components can be applied for the treatment of inflammation-related disorders, such as oxidative liver damage and inflammation diseases.

Synthesis, biological evaluation, hydration site thermodynamics, and chemical reactivity analysis of α-keto substituted peptidomimetics for the inhibition of Plasmodium falciparum.

A new series of peptidomimetic pseudo-prolyl-homophenylalanylketones were designed, synthesized and evaluated for inhibition of the Plasmodium falciparum cysteine proteases falcipain-2 (FP-2) and falcipain-3 (FP-3). In addition, the parasite killing activity of these compounds in human blood-cultured P. falciparum was examined. Of twenty-two (22) compounds synthesized, one peptidomimetic comprising a homophenylalanine-based α-hydroxyketone linked Cbz-protected hydroxyproline (39) showed the most potency (IC50 80 nM against FP-2 and 60 nM against FP-3). In silico analysis of these peptidomimetic analogs offered important protein-ligand structural insights including the role, by WaterMap, of water molecules in the active sites of these protease isoforms. The pseudo-dipeptide 39 and related compounds may serve as a promising direction forward in the design of competitive inhibitors of falcipains for the effective treatment of malaria.

Correction: Hill et al. A Multicenter, Randomized, Double-Blinded, Placebo-Controlled Clinical Trial to Evaluate the Efficacy and Safety of a Krill Oil, Astaxanthin, and Oral Hyaluronic Acid Complex on Joint Health in People with Mild Osteoarthritis. Nutrients 2023, 15, 3769.

In the original publication [...].

Ethanol Extracts of Cornus alba Improve Benign Prostatic Hyperplasia by Inhibiting Prostate Cell Proliferation through Modulating 5 Alpha-Reductase/Androgen Receptor Axis-Mediated Signaling.

PURPOSE: The aim of this study was to investigate the efficacy of ethanol extracts of Cornus alba (ECA) against benign prostatic hyperplasia (BPH) in vitro and in vivo. MATERIALS AND METHODS: The prostate stromal cells (WPMY-1) and epithelial cells (RWPE-1) were used to examine the action mechanism of ECA in BPH in vitro. ECA efficacy was evaluated in vivo using a testosterone propionate (TP)-induced BPH rat model. RESULTS: Treatment with ECA inhibited the proliferation of prostate cells by inducing G1-phase cell cycle arrest through the regulation of positive and negative proteins. Treatment of prostate cells with ECA resulted in alterations in the mitogen-activated protein kinases and protein kinase B signaling pathways. The transcriptional binding activity of the NF-κB motif was suppressed in both ECA-treated prostate cells. In addition, treatment with ECA altered the level of BPH-associated axis markers (5α-reductase, fibroblast growth factor-2, androgen receptor, epidermal growth factor, Bcl-2, and Bax) in both cell lines. Finally, the administration of ECA attenuated the enlargement of prostatic tissues in the TP-induced BPH rat model, accompanied by histology, immunoblot, and serum dihydrotestosterone levels. CONCLUSIONS: These results demonstrated that ECA exerted beneficial effects on BPH both in vitro and in vivo and might provide valuable information in the development of preventive or therapeutic agents for improving BPH.

Chrysanthemum morifolium and Its Bioactive Substance Enhanced the Sleep Quality in Rodent Models via Cl- Channel Activation.

Dried Chrysanthemum morifolium (Chry) flowers have been used in Korea as a traditional insomnia treatment. In this study, the sleep-promoting activity and improving sleep quality of Chry extract (ext) and its active substance linarin were analyzed by pentobarbital-induced sleep experiment in mice and electroencephalography (EEG), electromyogram (EMG) analysis in rats. In a dose-dependent manner, Chry ext and linarin promoted longer sleep duration in the pentobarbital-induced sleep test compared to pentobarbital-only groups at both hypnotic and subhypnotic doses. Chry ext administration also significantly improved sleep quality, as seen in the relative power of low-frequency (delta) waves when compared with the control group. Linarin increased Cl- uptake in the SH-SY5Y human cell line and chloride influx was reduced by bicuculline. After administration of Chry ext, the hippocampus, frontal cortex, and hypothalamus from rodents were collected and blotted for glutamic acid decarboxylase (GAD)65/67 and gamma-aminobutyric acid (GABA)A receptors subunit expression levels. The expression of α1-subunits, ß2-subunits, and GAD65/67 of the GABAA receptor was modulated in the rodent brain. In conclusion, Chry ext augments pentobarbital-induced sleep duration and enhances sleep quality in EEG waves. These effects might be due to the activation of the Cl- channel.

A Multicenter, Randomized, Double-Blinded, Placebo-Controlled Clinical Trial to Evaluate the Efficacy and Safety of a Krill Oil, Astaxanthin, and Oral Hyaluronic Acid Complex on Joint Health in People with Mild Osteoarthritis.

Osteoarthritis is a significant global health problem. Many patients seek more effective alternatives to nonsteroidal anti-inflammatory medicines or commercial supplements to manage joint pain and inflammation. FlexPro MD® (FP-MD) combines krill oil, astaxanthin, and lower molecular weight hyaluronic acid to support joint health. A 12-week, randomized, double-blind, placebo-controlled trial compared the efficacy and safety of FP-MD and placebo once daily in participants (n = 100) with mild osteoarthritis of the knee or hip joint. For the primary endpoint of joint pain score, per-protocol participants (n = 75) in the FP-MD group (n = 37) had a statistically significantly greater mean reduction from baseline in the Korean Visual Analog Scale (K-VAS) at week 12 compared with participants in the placebo group (n = 38) (20.8 ± 16.16 mm vs. 10.6 ± 17.58, p = 0.0105). The Korean Western Ontario and McMaster Universities Osteoarthritis Index (K-WOMAC) total score was also significantly improved in the FP-MD group at week 12 compared with placebo (-13.0 ± 13.62 vs. -5.5 ± 18.08, p = 0.0489), especially an improvement in pain score (-2.5 ± 2.92 vs. -1.3 ± 3.94, p = 0.02635). FP-MD group had greater improvement in joint function scoring by investigator assessment (p = 0.0127) and by group participants (p = 0.0070). A statistically significantly greater number of patients reported adverse events in the placebo group compared with the FP-MD group (16% vs. 4%, p = 0.0455), most commonly gastrointestinal disorders in both of the groups. These findings suggest that FP-MD is well tolerated and can be effectively used to address joint pain in patients diagnosed with mild osteoarthritis, the main symptom of this condition.

Derivatives of 3, 4, 5-Trimethoxycinnamic Acid Ameliorate Stress-Induced Anxiety in Mice and Rats.

Stress is an overwhelming problem associated with neuronal damage leading to anxiety and depression. The compound 3, 4, 5-trimethoxycinnamic acid (TMCA) has shown anti-stress effects; however, its derivatives remained unknown for their anxiolytic properties. Here, therefore, we investigated derivatives of TMCA (dTMCA) for their anxiolytic effects using immobilization and electric shock-induced stress in rats. Derivatives of TMCA ameliorated anxiety in mice and rats revealed by extended period of time spent in the open arms of elevated plus maze. Stress-mediated repression of tyrosine hydroxylase (TH) protein expression in the amygdala regions of rat brain and dopamine levels in the PC12 cells was restored by two selected derivatives (TMCA#5 and TMCA#9). Unlike TH expression, stress-induced protein expression of phospho-extracellular signal-regulated kinase (pERK) was unaffected by both derivatives in rats. Given the preferential inhibitory activity of dTMCA on dopamine and serotonin receptors, serotonergic road map of cellular signaling could be their target for anxiolytic effects. Thus, dTMCA would be promising agents to prevent neuronal damage associated with rampant stressful conditions.

Modafinil inhibits K(Ca)3.1 currents and muscle contraction via a cAMP-dependent mechanism.

Modafinil has been used as a psychostimulant for the treatment of narcolepsy. However, its primary mechanism of action remains elusive. Therefore, we examined the effects of modafinil on K(Ca)3.1 channels and vascular smooth muscle contraction. K(Ca)3.1 currents and channel activity were measured using a voltage-clamp technique and inside-out patches in mouse embryonic fibroblast cell line, NIH-3T3 fibroblasts. Intracellular adenosine 3',5'-cyclic monophosphate (cAMP) concentration was measured, and the phosphorylation of K(Ca)3.1 channel protein was examined using western blotting in NIH-3T3 fibroblasts and/or primary cultured mouse aortic smooth muscle cells (SMCs). Muscle contractions were recorded from mouse aorta and rat pulmonary artery by using a myograph developed in-house. Modafinil was found to inhibit K(Ca)3.1 currents in a concentration-dependent manner, and the half-maximal inhibition (IC(50)) of modafinil for the current inhibition was 6.8 ± 0.7 nM. The protein kinase A (PKA) activator forskolin also inhibited K(Ca)3.1 currents. The inhibitory effects of modafinil and forskolin on K(Ca)3.1 currents were blocked by the PKA inhibitors PKI(14-22) or H-89. In addition, modafinil relaxed blood vessels (mouse aorta and rat pulmonary artery) in a concentration-dependent manner. Modafinil increased cAMP concentrations in NIH-3T3 fibroblasts or primary cultured mouse aortic SMCs and phosphorylated K(Ca)3.1 channel protein in NIH-3T3 fibroblasts. However, open probability and single-channel current amplitudes of K(Ca)3.1 channels were not changed by modafinil. From these results, we conclude that modafinil inhibits K(Ca)3.1 channels and vascular smooth muscle contraction by cAMP-dependent phosphorylation, suggesting that modafinil can be used as a cAMP-dependent K(Ca)3.1 channel blocker and vasodilator.

Anti-Inflammatory Effect of Triterpene Saponins Isolated from Blue Cohosh (Caulophyllum thalictroides).

Blue cohosh has been used as a medicinal herb in eastern North America. It was commonly used as traditional medicines for the treatment of menopausal symptoms, rheumatic pain, and as anti-inflammatory remedy. Particularly, extract of blue cohosh roots has been used as anti-inflammatory antipyretic in traditional medicines. In the present study, we investigated the effects of blue cohosh components on the suppressive expression of iNOS or proinflammatory cytokines after the activation of microglia with lipopolysaccharide (LPS). The expression of iNOS, TNF-α, IL-1ß, and IL-6 was determined by western blotting or gene expression. Blue cohosh treatment suppressed the elevation of LPS-induced iNOS expression in a concentration-dependent manner in microglia cells. Blue cohosh constituents also suppressed the expression of TNF-α, IL-1ß, and IL-6. In addition, blue cohosh extract suppressed the expression of COX-2, iNOS, and proinflammatory cytokines in adrenal glands of mice. These results demonstrate that constituents of blue cohosh exert anti-inflammatory effects through the inhibition of expression of iNOS and proinflammatory cytokines. Therefore, blue cohosh may have therapeutic potential for the treatment of inflammation-related diseases.

Total synthesis of flocoumafen via knoevenagel condensation and intramolecular ring cyclization: general access to natural products.

The total synthesis and structure determination of cis- and trans-flocoumafen was described. The key synthetic steps involve Knoevenagel condensation with p-methoxybenzaldehyde, in situ decarboxylation and intramolecular ring cyclization to construct the tetralone skeleton. Stereospecific reduction of the O-alkylated ketone 13 afforded good yield of precusor alcohol 5. Final coupling of alcohol 5 with 4-hydroxy-coumarin yielded flocoumafen (1). Separation and structure determination of cis- and trans-flocoumafen through 2D NMR analyses-assisted computer simulation techniques for the evaluation of anticoagulant activities are reported for the first time. This method is useful for generating the core tetralone skeleton of 4-hydroxycoumarin derivatives and provides a generalized access to various warfarin type anticoagulants.

Simple synthesis of modafinil derivatives and their anti-inflammatory activity.

Simple synthesis of modafinil derivatives and their biological activity are described. The key synthetic strategies involve substitution and coupling reactions. We determined the anti-inflammatory effects of modafinil derivatives in cultured BV2 cells by measuring the inhibition of nitrite production and expression of iNOS and COX-2 after LPS stimulation. It was found that for sulfide analogues introduction of aliphatic groups on the amide part (compounds 11a­d) resulted in lower anti-inflammatory activity compared with cyclic or aromatic moieties (compounds 11e­k). However, for the sulfoxide analogues, introduction of aliphatic moieties (compounds 12a­d) showed higher anti-inflammatory activity than cyclic or aromatic fragments (compounds 12e­k) in BV-2 microglia cells.

Practical synthesis of hydroxychromenes and evaluation of their biological activity.

A simple and efficient seven steps synthesis of brodifacoum and difethialone from phenylacetyl chloride is described. The key synthetic strategies involve Friedel-Crafts acylation, intramolecular ring cyclization and condensation reaction in the presence of Brønsted-Lowry acids. It was found that brodifacoum showed favorable inhibiting activities on LPS-stimulated nitrite production in BV-2 microglia cells. Brodifacoum exhibited superior anti-inflammatory effects than difethialone. We expect that an efficient linear synthesis of 4-hydroxycoumarin derivatives and key fragments that are useful agents for the modulation of inflammation as well as inhibition of coagulation will be of practical use.

Phytoceramide shows neuroprotection and ameliorates scopolamine-induced memory impairment.

The function and the role phytoceramide (PCER) and phytosphingosine (PSO) in the central nervous system has not been well studied. This study was aimed at investigating the possible roles of PCER and PSO in glutamate-induced neurotoxicity in cultured neuronal cells and memory function in mice. Phytoceramide showed neuro-protective activity in the glutamate-induced toxicity in cultured cortical neuronal cells. Neither phytosphingosine nor tetraacetylphytosphingosine (TAPS) showed neuroproective effects in neuronal cells. PCER (50 mg/kg, p.o.) recovered the scopolamine-induced reduction in step-through latency in the passive avoidance test; however, PSO did not modulate memory function on this task. The ameliorating effects of PCER on spatial memory were confirmed by the Morris water maze test. In conclusion, through behavioral and neurochemical experimental results, it was demonstrated that central administration of PCER produces amelioration of memory impairment. These results suggest that PCER plays an important role in neuroprotection and memory enhancement and PCER could be a potential new therapeutic agent for the treatment of neurodegenerative diseases such as Alzheimer's disease.

Convenient synthesis and biological evaluation of modafinil derivatives: benzhydrylsulfanyl and benzhydrylsulfinyl [1,2,3]triazol-4-yl-methyl esters.

Simple synthesis and biological activities of modafinil derivatives are described. The key reactions include condensation of acid and propargyl alcohol, subsequent 1,3-dipolar cycloaddition reaction of alkynes and (3-azido-propyl)cyclohexane or (4-azido-butyl)benzene in the presence of sodium ascorbate and CuSO4·5H2O in excellent yield. They were then evaluated for the suppression of LPS-induced NO generation in vitro. It was found that all compounds showed moderate effects for suppression of LPS-induced NO generation.

Larvicidal activity of 4-hydroxycoumarin derivatives against Aedes aegypti.

CONTEXT: Coumarins are natural substances found in a variety of plants. It is well known that plant-derived natural products are extensively used as biologically active compounds. Among them, coumarins were the first preservatives used by man, originally in their natural state within plant tissues and then as natural materials obtained by water distillation. During our search for new types of coumarin derivatives possessing a larvicidal activity, we investigated the synthesis of 4-hydroxycoumarin derivatives. OBJECTIVE: The coumarin derivatives were synthesized and the structure determination and larvicidal effects were studied. MATERIALS AND METHODS: The structure analyses were conducted by nuclear magnetic resonance (NMR), and mass (MS) spectroscopy revealed that the coumarin derivatives were obtained in good yields, and the eight coumarin derivatives were 3-{1,2,3,4-tetrahydro-3-[4-(4-trifluoromethylbenzyloxy)phenyl}-1-naphthalen-1-on (1), 3-{1,2,3,4-tetrahydro-3-[4-(4-trifluoro methylbenzyloxy)phenyl}-1-naphthalen-1-ol (2), brodifacoum (3), difethialone (4), bromadiolone (5), 4-hydroxy-3-(1,2,3,4-tetrahydronaphthalen-1-yl)-2H-chromen-2-one (coumatetralyl) (6), cis-flocoumafen (7) and trans-flocoumafen (8). RESULTS: The compounds were tested against the F(21) laboratory strain of Aedes aegypti L. Brodifacoum and cis-flocoumafen mediated strong activity with an LC(50) values of 8.23 and 9.34 ppm, respectively. DISCUSSION AND CONCLUSION: The above indicates that brodifacoum may play a more important role in the toxicity of 4-hydroxycoumarin derivatives.

Inhibitory effects of BST406, a newly synthesized benzylideneacetophenone derivative, on abnormal vascular smooth muscle cell proliferation.

Benzylideneacetophenone analogues are known to have several significant biological activities, including antiinflammatory, antitumor, antibacterial, antiviral, and gastric-protective activities. However, the antiproliferative effects of benzylideneacetophenone analogues on vascular smooth muscle cells (VSMCs) are unknown. The aim of this study was to elucidate the antiproliferative effects and molecular mechanism of BST406, a newly synthesized benzylideneacetophenone derivative, on platelet-derived growth factor (PDGF)-BB-stimulated rat aortic VSMCs. BST406 inhibited [(3)H]-thymidine incorporation into DNA in VSMCs following treatment with PDGFBB 25 ng/ml. PDGF-BB-stimulated DNA synthesis was significantly reduced. Moreover, pretreatment with BST406 (0-10microM) suppressed the proliferation of PDGF-BB-stimulated cells in a concentration-dependent manner. We also investigated the mechanism of the antiproliferative effects of BST406 in PDGF-BB-stimulated VSMCs. In Western blot analysis, PDGF-BB-stimulated (25 ng/ml) phospholipase-C (PLC)gamma1 and Akt phosphorylation was inhibited by BST406 (0-10microM). However, BST406 did not inhibit the PDGF-receptor beta-chain (PDGF-Rbeta) and extracellular-regulated kinase 1 and 2 (ERK1/2) phosphorylation induced by PDGF-BB. To confirm that the inhibitory effects of BST406 are mediated through the inhibition of PLCgamma1 or Akt, the effects of inhibitors on cell viability were examined. U73122 completely inhibited PDGF-BB-induced proliferation of VSMCs. However, LY294002 10microM had no significant effects on PDGF-BB-induced proliferation. These findings suggest that the inhibitory effects of BST406 on the proliferation of PDGF-BB-stimulated VSMCs are mediated by suppression of the PLCgamma1 signaling pathways. Our observations may explain, in part, the mechanistic basis for the prevention of cardiovascular disease (such as atherosclerosis and restenosis after coronary angioplasty) by BST406.

Design, synthesis, and biological evaluation of 3,4,5-trimethoxyphenyl acrylamides as antinarcotic agents.

The synthesis and biological evaluation of 3,4,5-trimethoxyphenyl acrylamides 1a-f as novel antinarcotic agents are described. The molecules were prepared by the Wittig reaction, followed by a coupling reaction between 3,4,5-trimethoxycinnamic acid (9) and aliphatic amines, which resulted in good yields. When tested for biological activity, compounds 1d-f exhibited strong inhibitory effects on the morphine withdrawal syndrome in mice due to their high binding affinities with serotonergic 5-HT1A receptors.