Investigating multifaceted action of ibuprofen derivatives towards cox isozymes and interleukin-6 (IL-6) site correlating with various target sites.

The multifaceted action of new ibuprofen analogs has been investigated against inflammation, neurological and pro-inflammation factors. On the basis of ADMET (absorption, distribution, metabolism, excretion, and toxicity) analysis, molecular docking as well as molecular dynamics simulation, compound 3 was thought to have good anti-inflammatory activity. As the presence of structural interactions such as conventional hydrogen bonds and electrostatic interactions through the nitrogen atoms of the linker in compound 3 gave strong evidence of its potency. The major finding of the current work is that the presence of appropriate number of hetero atoms (NH, OH) in a compound makes it more efficient than the number of labile groups (i.e., hydroxyl groups). Additionally, the position of hetero atoms in a compound and orientation also play a vital role in its efficacy. It was also screened for in vitro anti-inflammatory activity by membrane stability method, where it has shown 90.8% protection of RBC hemolysis. Thus, compound 3 with effective structural features may have good anti-inflammatory activity.Communicated by Ramaswamy H. Sarma.

Effect of Detergents on Activity and Magnesium-Dependent Properties of Different Isoforms of Na+,K+-ATPase in the Crude Membrane Fraction of Rat Cerebral Cortex.

We studied the effect of various detergents (Tween-20, Triton X-100, and sodium deoxycholate) on activity and magnesium-dependent properties of Na+,K+-ATPase of the crude membrane fraction of rat cerebral cortex. All studied detergents significantly increased activity of the studied enzyme in a concentration-dependent manner. Sodium deoxycholate provided significantly higher values Na+,K+-ATPase activity (by ≈50%) than Triton X-100 and Tween-20. In the presence of Triton X-100, a changed pattern of the dependence of enzyme activity on the concentration of magnesium ions in the incubation solution was noted. Separate measurement of activities of Na+,K+-ATPase isoforms made it possible to assume that changes in magnesium-dependent properties are due to the predominant effect of Triton X-100 on ouabain-sensitive α2- and α3-isoforms.

Carbonic anhydrase activation profile of indole-based derivatives.

Carbonic Anhydrase Activators (CAAs) could represent a novel approach for the treatment of Alzheimer's disease, ageing, and other conditions that require remedial achievement of spatial learning and memory therapy. Within a research project aimed at developing novel CAAs selective for certain isoforms, three series of indole-based derivatives were investigated. Enzyme activation assay on human CA I, II, VA, and VII isoforms revealed several effective micromolar activators, with promising selectivity profiles towards the brain-associated cytosolic isoform hCA VII. Molecular modelling studies suggested a theoretical model of the complex between hCA VII and the new activators and provide a possible explanation for their modulating as well as selectivity properties. Preliminary biological evaluations demonstrated that one of the most potent CAA 7 is not cytotoxic and is able to increase the release of the brain-derived neurotrophic factor (BDNF) from human microglial cells, highlighting its possible application in the treatment of CNS-related disorders.

circ-PRKCI targets miR-1294 and miR-186-5p by downregulating FOXK1 expression to suppress glycolysis in hepatocellular carcinoma.

Numerous human circular RNAs (circRNAs/circ) have been functionally characterized. However, the potential role of circ-protein kinase C iota (PRKCI) in hepatocellular carcinoma (HCC) remains unknown. The effects of each transfection and expression levels of circ-PRKCI, microRNA (miR)-1294, miR-186-5p and forkhead box K1 (FOXK1) in HCC cells were analyzed using reverse transcription-quantitative PCR analysis. The interactions between circ-PRKCI and miR-1294 or miR-186-5p, and miR-1294 or miR-186-5p and FOXK1 were validated using dual luciferase reporter assays. The viability, invasion and migration of HCC cells were determined using Cell Counting Kit-8, Transwell and wound healing assays, respectively. The expression levels of FOXK1, hexokinase-2 (HK2), glucose transporter 1 (GLUT1) and lactate dehydrogenase A (LDHA) in HCC cells were analyzed using western blotting. The levels of glucose and lactic acid in the cultured supernatant were detected using commercially available kits. The results of the present study revealed that miR-1294 and miR-186-5p expression levels were downregulated in the HCC cell line, HCCLM3, and were subsequently downregulated by circ-PRKCI overexpression and upregulated by the knockdown of circ-PRKCI. circ-PRKCI overexpression promoted the viability, invasion and migration of HCCLM3 cells, which was also reversed by the overexpression of miR-1294 and miR-186-5p. In addition, the overexpression of circ-PRKCI upregulated FOXK1 expression levels, while the overexpression of miR-1294 and miR-186-5p downregulated FOXK1 expression levels. Conversely, the knockdown of circ-PRKCI expression downregulated FOXK1 expression levels, while the knockdown of miR-1294 and miR-186-5p upregulated FOXK1 expression levels. Furthermore, circ-PRKCI was identified to target miR-1294 and miR-186-5p, and miR-1294 and miR-186-5p were subsequently found to target FOXK1. The overexpression of circ-PRKCI also increased glucose and lactic acid levels, while the knockdown of FOXK1 decreased glucose and lactic acid levels. The knockdown of circ-PRKCI decreased glucose and lactic acid levels, which were reversed by FOXK1 overexpression. In conclusion, the findings of the present study suggested that circ-PRKCI may promote the viability, invasion and migration of HCC cells by sponging miR-1294 and miR-186-5p to upregulate FOXK1 expression levels.

Elucidation of plasma protein binding, blood partitioning, permeability, CYP phenotyping and CYP inhibition studies of Withanone using validated UPLC method: An active constituent of neuroprotective herb Ashwagandha.

ETHNOPHARMACOLOGICAL RELEVANCE: Withanone (WN), an active constituent of Withania somnifera commonly called Ashwagandha has remarkable pharmacological responses along with neurological activities. However, for a better understanding of the pharmacokinetic and pharmacodynamic behavior of WN, a comprehensive in-vitro ADME (absorption, distribution, metabolism, and excretion) studies are necessary. AIM OF THE STUDY: A precise, accurate, and sensitive reverse-phase ultra-performance liquid chromatographic method of WN was developed and validated in rat plasma for the first time. The developed method was successfully applied to the in-vitro ADME investigation of WN. MATERIAL AND METHODS: The passive permeability of WN was assayed using PAMPA plates and the plasma protein binding (PPB) was performed using the equilibrium dialysis method. Pooled liver microsomes of rat (RLM) and human (HLM) were used for the microsomal stability, CYP phenotyping, and inhibition studies. CYP phenotyping was evaluated using the specific inhibitors. CYP inhibition study was performed using specific probe substrates along with WN or specific inhibitors. RESULTS: WN was found to be stable in the simulated gastric and intestinal environment and has a high passive permeability at pH 4.0 and 7.0 in PAMPA assay. The PPB of WN at 5 and 20 µg/mL concentrations were found to be high i.e. 82.01 ± 1.44 and 88.02 ± 1.15%, respectively. The in vitro half-life of WN in RLM and HLM was found to be 59.63 ± 2.50 and 68.42 ± 2.19 min, respectively. CYP phenotyping results showed that WN was extensively metabolized by CYP 3A4 and1A2 enzymes in RLM and HLM. However, the results of CYP Inhibition studies showed that none of the CYP isoenzymes were potentially inhibited by WN in RLM and HLM. CONCLUSION: The in vitro results of pH-dependent stability, plasma stability, permeability, PPB, blood partitioning, microsomal stability, CYP phenotyping, and CYP inhibition studies demonstrated that WN could be a better phytochemical for neurological disorders.

Exploration of cytochrome P450 inhibition mediated drug-drug interaction potential of kratom alkaloids.

In vitro cytochrome P450 inhibition of major kratom alkaloids: mitragynine (MTG), speciogynine (SPG), speciocilliatine (SPC), corynantheidine (COR), 7-hydroxymitragynine (7HMG) and paynantheine (PAY) was evaluated using human liver microsomes (HLMs) to understand their drug-drug interaction potential. CYP450 isoform-specific substrates of CYP1A2, 2C8, 2C9, 2C19, 2D6, and 3A4/5 were incubated in HLMs with or without alkaloids. Preliminary CYP450 inhibition (IC50) data were generated for each of these isoforms. In addition, the type of inhibition and estimation of the inhibition constants (Ki) of MTG and COR were determined. Among the tested alkaloids, MTG and COR were potent inhibitors of CYP2D6 (IC50, 2.2 and 4.2 µM, respectively). Both MTG and COR exhibited competitive inhibition of CYP2D6 activity and the Ki were found to be 1.1 and 2.8 µM, respectively. SPG and PAY showed moderate inhibition of CYP2D6 activity. Additionally, moderate inhibitory effects by SPC, MTG, and SPG were observed on CYP2C19 activity. Interestingly, inhibition of only midazolam hydroxylase CYP3A4/5 activity by COR, PAY, and MTG was observed while no inhibitory effect was observed when testosterone was used as a probe substrate. In conclusion, MTG and COR may lead to clinically significant adverse drug interactions upon coadministration of drugs that are substantially metabolized by CYP2D6.

Design, synthesis and biological activity of selective hCAs inhibitors based on 2-(benzylsulfinyl)benzoic acid scaffold.

A large library of derivatives based on the scaffold of 2-(benzylsulfinyl)benzoic acid were synthesised and tested as atypical inhibitors against four different isoforms of human carbonic anhydrase (hCA I, II, IX and XII, EC 4.2.1.1). The exploration of the chemical space around the main functional groups led to the discovery of selective hCA IX inhibitors in the micromolar/nanomolar range, thus establishing robust structure-activity relationships within this versatile scaffold. HPLC separation of some selected chiral compounds and biological evaluation of the corresponding enantiomers was performed along with molecular modelling studies on the most active derivatives.

Isolation, synthesis, and drug interaction potential of secondary metabolites derived from the leaves of miracle tree (Moringa oleifera) against CYP3A4 and CYP2D6 isozymes.

BACKGROUND: Moringa oleifera Lam. is known as a drumstick tree that is widely cultivated in various subtropical and tropical provinces. Previous studies indicated that both aqueous and methanolic extracts of M. oleifera leaves have potent inhibitory effects on two major drug metabolizing Cytochrome P450 enzymes, namely, CYP3A4 and CYP2D6. PURPOSE: The current study was aimed to isolate the secondary metabolites from M. oleifera and investigate their cytotoxicity and inhibitory effects on CYP3A4 and CYP2D6 to assess their herb-drug interaction (HDI) potential. METHODS: Chemical structure elucidation was achieved by interpreting the spectroscopic data (UV, IR, 1D, and 2D NMR experiments), confirming by HR-ESI-MS, and comparing with the previously reported data in the literature. All the isolates were evaluated for their cytotoxicity against a panel of cell lines (SK-MEL, KB, BT-549, SK-OV-3, VERO, LLC-PK1, and HepG2) and inhibition of two principal CYP isozymes (CYP3A4 and CYP2D6). RESULTS: Phytochemical investigation of M. oleifera leaves resulted in the isolation and characterization of one new compound, namely omoringone (1), along with twelve known secondary metabolites (2-13) belonging to several chemical classes including flavonoids, terpenoids, lignans, and phenylalkanoids. A plausible biosynthetic pathway for compound 1 was provided. Because of the low isolation yield and limited supply, omoringone (1) and niazirin (12) were successively synthesized. No cytotoxicity was observed on any of the tested cell lines up to 50 µM. The extract exhibited an inhibitory effect on CYP3A4 isoform (IC50 = 52.5 ±â€¯2.5 µg/ml). Among the isolates, 1-4 and 7-9 inhibited CYP3A4 with the IC50 values ranging from 41.5 to 100 µM with no remarkable effect on CYP2D6 isozyme. CONCLUSION: This work aided in ascertaining components of M. oleifera contributing to CYP3A4 inhibition exhibited by the extract using an in vitro assay. Nonetheless, further studies are warranted to determine the bioavailability of the phytochemicals and extrapolate these findings in more physiologically relevant conditions to further establish the clinical relevance of in vitro observations.

Which phosphodiesterase can decrease cardiac effects of 5-HT4 receptor activation in transgenic mice?

Serotonin (5-hydroxy-tryptamine, 5-HT) exerted concentration-dependent positive inotropic effects or positive chronotropic effects in transgenic (TG) mice which overexpress the human 5-HT4a receptor in the heart but not in littermate wild-type (WT) mice. These positive inotropic effects and positive chronotropic effects are thought to be mediated by cyclic adenosine 3',5'-monophosphate (cAMP) in TG cardiomyocytes. To determine whether these effects are antagonized by endogenous phosphodiesterases (PDEs), the inotropic and chronotropic effects of 5-HT were tested in the additional presence of the PDE inhibitor erythro-9-(2-hydroxy-3-nonyl)adenine hydrochloride (EHNA) (1 µM, a PDE2 inhibitor) or cilostamide (1 µM, a PDE3 inhibitor), rolipram (0.1 µM and 1 µM, a PDE4 inhibitor), and their combinations. For comparison, 3-isobutyl-1-methylxanthine (IBMX), an unspecific PDE inhibitor, was investigated. The use of 10 µM IBMX, the combination of rolipram (1 µM) and EHNA (1 µM), and the combination of rolipram (0.1 µM) and cilostamide (1 µM) each increased the potency of 5-HT to elevate the force of contraction in TG mice, but not the potency of 5-HT to increase the beating rate in TG mice. This indicates that PDE4 and PDE2 regulate the inotropic but not the chronotropic effects of 5-HT in TG mice. In contrast, cilostamide (1 µM) alone, EHNA (1 µM) alone, or in combination decreased the potency of 5-HT to increase force of contraction in TG mice. In summary, our present data suggest that the positive chronotropic effect of 5-HT in TG mice does not involve PDE activities, whereas the positive inotropic effect of 5-HT and the basal force in TG mice are diminished by endogenous activity of PDE4. Phosphorylation of PDE4, when PDE2 or PDE3 is inhibited, might enhance the activity of PDE4.

Discovery of novel 1,3-diaryltriazene sulfonamides as carbonic anhydrase I, II, VII, and IX inhibitors.

A series of new 1,3-diaryltriazene sulfonamides was synthesised by reaction of diazonium salt of metanilamide (3-aminobenzene sulfonamide) with substituted aromatic amines. The obtained new compounds were assayed as inhibitors of four physiologically and pharmacologically relevant human (h) isoforms of carbonic anhydrases (CA, EC 4.2.1.1), specifically, hCA I, hCA II, and hCA VII (cytosolic isoforms), as well as the tumour-associated membrane-bound isoform hCA IX. All isoforms investigated here were inhibited by the newly synthesised 1,3-diaryltriazene sulfonamide derivatives from the micromolar to the nanomolar range. The cytosolic isoforms were inhibited with Kis in the range of 92.3-8371.1 nM (hCA I), 4.3-9194.0 nM (hCA II), and 15.6-9477.8 nM (hCA VII), respectively. For the membrane-bound tumour-associated isoform hCA IX, the KI-s ranged between 50.8 and 9268.5 nM. The structure-activity relationship (SAR) with these newly synthesised metanilamide derivatives are discussed in detail.

Carbonic anhydrase inhibition with a series of novel benzenesulfonamide-triazole conjugates.

We report the synthesis and characterisation of a novel series of triazole benzenesulfonamide derivatives, which incorporate the general pharmacophore associated with carbonic anhydrase (CA, EC 4.2.1.1) inhibitors. The synthesised compounds were tested in vitro against four human carbonic anhydrase (hCA, EC 4.2.1.1) isozymes, hCA I, hCA II, hCA IV and hCA IX. The obtained results showed that the tumour-associated hCA IX was the most sensitive to inhibition with the synthesised derivatives, with the triazolo-pyridine benzenesulfonamides 14, 16 and 17 being the most effective inhibitors. Some selected compounds were chosen for a single dose anti-proliferative activity testing against a panel of 57 human tumour cell lines and show some anti-proliferative activity ex vivo.

Combined inhibition of atypical PKC and histone deacetylase 1 is cooperative in basal cell carcinoma treatment.

Advanced basal cell carcinomas (BCCs) circumvent Smoothened (SMO) inhibition by activating GLI transcription factors to sustain the high levels of Hedgehog (HH) signaling required for their survival. Unfortunately, there is a lack of efficacious therapies. We performed a gene expression-based drug repositioning screen in silico and identified the FDA-approved histone deacetylase (HDAC) inhibitor, vorinostat, as a top therapeutic candidate. We show that vorinostat only inhibits proliferation of BCC cells in vitro and BCC allografts in vivo at high dose, limiting its usefulness as a monotherapy. We leveraged this in silico approach to identify drug combinations that increase the therapeutic window of vorinostat and identified atypical PKC Ɩ/ʎ (aPKC) as a HDAC costimulator of HH signaling. We found that aPKC promotes GLI1-HDAC1 association in vitro, linking two positive feedback loops. Combination targeting of HDAC1 and aPKC robustly inhibited GLI1, lowering drug doses needed in vitro, in vivo, and ex vivo in patient-derived BCC explants. We identified a bioavailable and selective small-molecule aPKC inhibitor, bringing the pharmacological blockade of aPKC and HDAC1 into the realm of clinical possibility. Our findings provide a compelling rationale and candidate drugs for combined targeting of HDAC1 and aPKC in HH-dependent cancers.

N-Nitrosulfonamides: A new chemotype for carbonic anhydrase inhibition.

A series of N(1)-substituted aromatic sulfonamides was obtained by applying a selective sulfonamide nitration synthetic strategy leading to Ar-SO2NHNO2 derivatives which were investigated as carbonic anhydrase (CA, EC 4.2.1.1) inhibitors. Two human (h) hCA isoforms, the cytosolic hCA II and the transmembrane hCA IX, in addition to the fungal enzyme from Malassezia globosa, MgCA, were included in the study. Most of the new compounds reported selectively inhibited hCA IX over hCA II and at the same time showed effective MgCA inhibitory properties, with KIs ranging between 0.22 and 8.09µM. The N-nitro sulfonamides are a new chemotype with CA inhibitory effects. As hCA IX was recently validated as antitumor/antimetastatic drug target, its selective inhibition could be exploited for interesting biomedical applications. Moreover, due to the effective MgCAs inhibitory properties of the N-nitro sulfonamides, of considerable interest in the cosmetics field as potential anti-dandruff agents, the N-nitro sulfonamides may be considered as interesting leads for the design of more efficient compounds targeting fungal enzymes.

Microwave assisted synthesis of novel acridine-acetazolamide conjugates and investigation of their inhibition effects on human carbonic anhydrase isoforms hCA I, II, IV and VII.

4-Amino-N-(5-sulfamoyl-1,3,4-thiadiazol-2-yl)benzamide was condensed with cyclic-1,3-diketones (dimedone and cyclohexane-1,3-dione) and aromatic aldehydes under microwave irradiation, leading to a series of acridine-acetazolamide conjugates. The new compounds were investigated as inhibitors of carbonic anhydrases (CA, EC 4.2.1.1), and more precisely cytosolic isoforms hCA I, II, VII and membrane-bound one hCA IV. All investigated isoforms were inhibited in low micromolar and nanomolar range by the new compounds. hCA IV and VII were inhibited with KIs in the range of 29.7-708.8nM (hCA IV), and of 1.3-90.7nM (hCA VII). For hCA I and II the KIs were in the range of 6.7-335.2nM (hCA I) and of 0.5-55.4nM (hCA II). The structure-activity relationships (SAR) for the inhibition of these isoforms with the acridine-acetazolamide conjugates reported here were delineated.

Thioxocoumarins Show an Alternative Carbonic Anhydrase Inhibition Mechanism Compared to Coumarins.

A series of coumarins and the corresponding 2-thioxocoumarines were prepared and tested for their inhibition profiles against four physiologically relevant human carbonic anhydrases (hCAs, EC 4.2.1.1), isoforms hCA I, II, IX, and XII. The X-ray crystal structure of 6-hydroxy-2-thioxocoumarin bound to hCA II revealed an unprecedented and unexpected inhibition mechanism for this new class of inhibitors when compared to isostructural coumarins. Unlike coumarins which are hydrolyzed by the esterase CA activity to the corresponding 2-hydroxy-cinnamic acid derivatives, the 2-thioxocoumarin was observed intact when bound to hCA II, with its exo-sulfur atom anchored to the zinc-coordinated water molecule, whereas the scaffold establishing favorable contacts with amino acid residues from the active site. This inhibition mechanism is very different from the one observed for hydrolyzed coumarins, which occlude the entrance of the active site cavity. This versatility in the binding mode of coumarins/thioxocoumarins has important consequences for the design of isoform-selective CA inhibitors, some of which are in clinical use or clinical development for various pathologies, among which glaucoma, edema, epilepsy, neuropathic pain, and hypoxic tumors.

The effect of caffeic acid phenethyl ester (CAPE) on metabolic enzymes including acetylcholinesterase, butyrylcholinesterase, glutathione S-transferase, lactoperoxidase, and carbonic anhydrase isoenzymes I, II, IX, and XII.

Caffeic acid phenethyl ester (CAPE) is an active component of honeybee propolis extracts. Carbonic anhydrases (CAs, EC 4.2.1.1) are widespread and intensively studied metalloenzymes present in higher vertebrates including humans as many diverse isoforms. Acetylcholinesterase (AChE) is responsible for acetyl choline (ACh) hydrolysis and plays a fundamental role in nerve impulse transmission by terminating the action of the ACh neurotransmitter at cholinergic synapses and neuromuscular junctions. Butyrylcholinesterase (BChE) is another enzyme abundantly present in the liver and released into blood in a soluble form. Lactoperoxidase (LPO) is an enzyme involved in fighting pathogenic microorganisms whereas glutathione S-transferases (GSTs) are dimeric proteins present both in prokaryotic and eukaryotic organisms and involved in cellular detoxification mechanisms. In the present study, the inhibition effect of CAPE on human carbonic anhydrase (hCA) isoforms I, II, IX, and XII, AChE, BChE, LPO, and GST was evaluated. CAPE inhibited these enzymes with Kis in the range between micromolar to picomolar. The best inhibitory effect was observed against AChE and BChE.

CD44(high) /ALDH1(high) head and neck squamous cell carcinoma cells exhibit mesenchymal characteristics and GSK3ß-dependent cancer stem cell properties.

BACKGROUND: CD44 and aldehyde dehydrogenase 1 (ALDH1) have been shown to be useful markers for identification of cancer stem cells (CSCs). We previously reported that glycogen synthase kinase 3ß (GSK3ß) is involved in regulation of the self-renewal ability of head and neck squamous cell carcinoma (HNSCC) CSCs. The purpose of the present study was to clarify the role of GSK3ß in CD44(high) /ALDH1(high) HNSCC cells. METHODS: Cells with greater expression of CD44 and higher ALDH1 enzymatic activity were FACS sorted from the OM-1 HNSCC cell line. The self-renewal ability of CD44(high) /ALDH1(high) cells was then examined using a tumor sphere formation assay. mRNA expressions of the stem cell markers Sox2, Oct4, and Nanog, as well as GSK3ß were evaluated by real-time RT-PCR. RESULTS: CD44(high) /ALDH1(high) cells exhibited higher tumor sphere forming ability and increased expression of stem cell markers as compared with CD44(high) /ALDH1(low) cells. Interestingly, spindle-shaped cells positive for vimentin were found in the CD44(high) /ALDH1(high) but not the CD44(high) /ALDH1(low) cell population. In addition, the ALDH1 activity and sphere forming ability of CD44(high) /ALDH1(high) cells was significantly inhibited by GSK3ß knockdown. On the other hand, CD44(high) /ALDH1(low) cells exhibited high epidermal growth factor receptor (EGFR) expression and increased cell growth. CONCLUSIONS: Our results show that GSK3ß plays a major role in maintenance of stemness of CD44(high) /ALDH1(high) HNSCC cells. Additionally, they indicate a close relationship between CSC and mesenchymal characteristics in HNSCC.

Micromolar sodium fluoride mediates anti-osteoclastogenesis in Porphyromonas gingivalis-induced alveolar bone loss.

Osteoclasts are bone-specific multinucleated cells generated by the differentiation of monocyte/macrophage lineage precursors. Regulation of osteoclast differentiation is considered an effective therapeutic approach to the treatment of bone-lytic diseases. Periodontitis is an inflammatory disease characterized by extensive bone resorption. In this study, we investigated the effects of sodium fluoride (NaF) on osteoclastogenesis induced by Porphyromonas gingivalis, an important colonizer of the oral cavity that has been implicated in periodontitis. NaF strongly inhibited the P. gingivalis-induced alveolar bone loss. That effect was accompanied by decreased levels of cathepsin K, interleukin (IL)-1ß, matrix metalloproteinase 9 (MMP9), and tartrate-resistant acid phosphatase, which were up-regulated during P. gingivalis-induced osteoclastogenesis. Consistent with the in vivo anti-osteoclastogenic effect, NaF inhibited osteoclast formation caused by the differentiation factor RANKL (receptor activator of nuclear factor κB ligand) and macrophage colony-stimulating factor (M-CSF). The RANKL-stimulated induction of the transcription factor nuclear factor of activated T cells (NFAT) c1 was also abrogated by NaF. Taken together, our data demonstrate that NaF inhibits RANKL-induced osteoclastogenesis by reducing the induction of NFATc1, ultimately leading to the suppressed expression of cathepsin K and MMP9. The in vivo effect of NaF on the inhibition of P. gingivalis-induced osteoclastogenesis strengthens the potential usefulness of NaF for treating periodontal diseases.

Influences of Re Du Ning Injection, a traditional Chinese medicine injection, on the CYP450 activities in rats using a cocktail method.

ETHNOPHARMACOLOGICAL RELEVANCE: Re Du Ning Injection (RDN), a traditional Chinese medicine injection, is made from the extracts of Lonicerae japonicae flos (LJF), Artemisiae annuae herba (AAH) and Gardeniae fructus (GF). Since last decade, RDN has been widely used in China for the treatment of fever, inflammation, allergy and viral infection. AIM OF THE STUDY: To elucidate the potential influences of RDN on the activities of four cytochrome P450 (CYP) isozymes in rats (CYP1A2, CYP2C11, CYP2D1 and CYP3A1/2) by "cocktail method". MATERIALS AND METHODS: A sensitive and specific LC-MS method capable of simultaneous quantification of four substrates and their metabolites in rat plasma was developed and validated. Relative activity estimation of four isozymes was carried out by comparing plasma pharmacokinetics of substrates and their metabolites (phenacetin/ paracetamol for CYP1A2, tolbutamide/4-hydroxytolbutamide for CYP2C11, dextromethorphan/ dextrorphan for CYP2D1 and dapsone/N-acetyl dapsone for CYP3A1/2) between control and RDN treatment groups. RESULTS: Compared with control group, RDN at different levels could increase the total amount of tolbutamide, dextromethorphan and dapsone absorbed into blood, while decrease the total amount of phenacetin absorbed into blood at low and medium dosage and increase it at high dosage. CONCLUSIONS: RDN could inhibit the activities of CYP2C11, CYP2D1 and CYP3A1/2, induce the activity of CYP1A2 at low and medium dosage but inhibit it at high dosage. The results indicated that drug co-administrated with RDN may need dose adjustment.