Ultrastructural and Morphological Effects in T-Lymphoblastic Leukemia CEM-SS Cells Following Treatment with Nordamnacanthal and Damnacanthal from Roots of Morinda elliptica.

BACKGROUND: Morinda elliptica (family Rubiaceae), locally known as 'mengkudu kecil', has been used by the Malays for medicinal purposes. Anthraquinones isolated from the roots of Morinda elliptica, namely nordamnacanthal and damnacanthal, have been widely reported to exhibit anticancer and antioxidant properties in various cancer models in vitro and in vivo. AIM: This study analyzed the morphological and ultrastructural effects of damnacanthal and nordamnacanthal on T-lymphoblastic leukemia CEM-SS cells. METHOD: Light microscopy, Giemsa staining, Wright's staining, scanning electron microscopy, and transmission electron microscopy were carried out to determine apoptosis, necrosis, and ultrastructural changes that occurred within the cells. RESULTS: The outcomes showed that these compounds induced cell death by apoptosis and necrosis, specifically at higher doses of 10 and 30 µg/mL. Condensation and fragmentation of the nuclear chromatin, which further separated into small, membrane-bound vesicles known as apoptotic bodies, were observed in the nuclei and cytoplasm. The plasma membranes and cytoskeletons also showed marked morphological changes upon treatment with damnacanthal and nordamnacanthal, indicating apoptosis. CONCLUSION: Therefore, we report that damnacanthal and nordamnacanthal exhibit anticancer properties by inducing apoptosis and necrosis in CEM-SS cells, and they have potential as a drug for the treatment of T-lymphoblastic leukemia.

In silico studies, nitric oxide, and cholinesterases inhibition activities of pyrazole and pyrazoline analogs of diarylpentanoids.

A new series of pyrazole, phenylpyrazole, and pyrazoline analogs of diarylpentanoids (excluding compounds 3a, 4a, 5a, and 5b) was pan-assay interference compounds-filtered and synthesized via the reaction of diarylpentanoids with hydrazine monohydrate and phenylhydrazine. Each analog was evaluated for its anti-inflammatory ability via the suppression of nitric oxide (NO) on IFN-γ/LPS-activated RAW264.7 macrophage cells. The compounds were also investigated for their inhibitory capability toward acetylcholinesterase (AChE) and butyrylcholinesterase (BChE), using a modification of Ellman's spectrophotometric method. The most potent NO inhibitor was found to be phenylpyrazole analog 4c, followed by 4e, when compared with curcumin. In contrast, pyrazole 3a and pyrazoline 5a were found to be the most selective and effective BChE inhibitors over AChE. The data collected from the single-crystal X-ray diffraction analysis of compound 5a were then applied in a docking simulation to determine the potential binding interactions that were responsible for the anti-BChE activity. The results obtained signify the potential of these pyrazole and pyrazoline scaffolds to be developed as therapeutic agents against inflammatory conditions and Alzheimer's disease.

Anticancer Potential of Damnacanthal and Nordamnacanthal from Morinda elliptica Roots on T-lymphoblastic Leukemia Cells.

BACKGROUND: This study reports on the cytotoxic properties of nordamnacanthal and damnacanthal, isolated from roots of Morinda elliptica on T-lymphoblastic leukaemia (CEM-SS) cell lines. METHODS: MTT assay, DNA fragmentation, ELISA and cell cycle analysis were carried out. RESULTS: Nordamnacanthal and damnacanthal at IC50 values of 1.7 µg/mL and10 µg/mL, respectively. At the molecular level, these compounds caused internucleosomal DNA cleavage producing multiple 180-200 bp fragments that are visible as a "ladder" on the agarose gel. This was due to the activation of the Mg2+/Ca2+-dependent endonuclease. The induction of apoptosis by nordamnacanthal was different from the one induced by damnacanthal, in a way that it occurs independently of ongoing transcription process. Nevertheless, in both cases, the process of dephosphorylation of protein phosphates 1 and 2A, the ongoing protein synthesis and the elevations of the cytosolic Ca2+ concentration were not needed for apoptosis to take place. Nordamnacanthal was found to have a cytotoxic effect by inducing apoptosis, while damnacanthal caused arrest at the G0/G1 phase of the cell cycle. CONCLUSION: Damnacanthal and nordamnacanthal have anticancer properties, and could act as potential treatment for T-lymphoblastic leukemia.

Inhibition of nitric oxide and prostaglandin E2 production by pyrrolylated-chalcones: Synthesis, biological activity, crystal structure analysis, and molecular docking studies.

In search of potent anti-inflammatory agents, twenty-four chalcone derivatives including seven new compounds (13 - 17, 21 and 23) containing pyrrole moiety were designed, synthesized, and assessed for their nitric oxide (NO) and prostaglandin E2 (PGE2) suppression ability on IFN-γ/LPS-induced RAW 264.7 macrophage cells. Results showed that none of the synthesized compounds were PAINS-associated molecules, with 3-(2,5-dimethoxyphenyl)-1-(1H-pyrrol-2-yl)-prop-2-en-1-one (compound 16) exhibiting remarkable inhibition activity towards PGE2 and NO production with IC50 values of 0.5 ±â€¯1.5 µM and 12.1 ±â€¯1.5 µM, respectively. Physicochemical and ADMET studies showed that majority of the compounds obey to Lipinski's rule of five (RO5) having high blood brain barrier (BBB) penetration, human intestinal absorption (HIA), P- glycoprotein (PgP) inhibition and plasma binding protein (PPB) inhibition. The obtained atomic coordinates for the single-crystal XRD of 16 were then applied in a molecular docking simulation, and compound 16 was found to participate in a number of important binding interactions in the binding sites of ERK and mPGES-1. Based on these results, we have observed the potential of compound 16 as a new hit anti-inflammatory agent, and these findings could serve as a basis for further studies on its mechanism of action.

The Curcumin Analogue, MS13 (1,5-Bis(4-hydroxy-3- methoxyphenyl)-1,4-pentadiene-3-one), Inhibits Cell Proliferation and Induces Apoptosis in Primary and Metastatic Human Colon Cancer Cells.

The cytotoxic and apoptotic effects of turmeric (Curcuma longa) on colon cancer have been well documented but specific structural modifications of curcumin have been shown to possess greater growth-suppressive potential on colon cancer than curcumin. Therefore, the aim of this study is to identify the anti-cancer properties of curcumin analogue-MS13, a diarylpentanoid on the cytotoxicity, anti-proliferative and apoptotic activity of primary (SW480) and metastatic (SW620) human colon cancer cells. A cell viability assay showed that MS13 has greater cytotoxicity effect on SW480 (EC50: 7.5 ± 2.8 µM) and SW620 (EC50: 5.7 ± 2.4 µM) compared to curcumin (SW480, EC50: 30.6 ± 1.4 µM) and SW620, EC50: 26.8 ± 2.1 µM). Treatment with MS13 at two different doses 1X EC50 and 2X EC50 suppressed the colon cancer cells growth with lower cytotoxicity against normal cells. A greater anti-proliferative effect was also observed in MS13 treated colon cancer cells compared to curcumin at 48 and 72 h. Subsequent analysis on the induction of apoptosis showed that MS13 treated cells exhibited morphological features associated with apoptosis. The findings are also consistent with cellular apoptotic activities shown by increased caspase-3 activity and decreased Bcl-2 protein level in both colon cancer cell lines. In conclusion, MS13 able to suppress colon cancer cell growth by inhibiting cell proliferation and induce apoptosis in primary and metastatic human colon cancer cells.

Mechanism of Apoptosis Induced by Curcumin in Colorectal Cancer.

Colorectal cancer (CRC) is among the top three cancer with higher incident and mortality rate worldwide. It is estimated that about over than 1.1 million of death and 2.2 million new cases by the year 2030. The current treatment modalities with the usage of chemo drugs such as FOLFOX and FOLFIRI, surgery and radiotherapy, which are usually accompanied with major side effects, are rarely cured along with poor survival rate and at higher recurrence outcome. This trigger the needs of exploring new natural compounds with anti-cancer properties which possess fewer side effects. Curcumin, a common spice used in ancient medicine was found to induce apoptosis by targeting various molecules and signaling pathways involved in CRC. Disruption of the homeostatic balance between cell proliferation and apoptosis could be one of the promoting factors in colorectal cancer progression. In this review, we describe the current knowledge of apoptosis regulation by curcumin in CRC with regard to molecular targets and associated signaling pathways.

Metabolite characterization of different palm date varieties and the correlation with their NO inhibitory activity, texture and sweetness.

The aim of this study was to examine the variation in metabolite constituents of five commercial varieties of date fruits; Ajwa, Safawi and Ambar which originated from Madinah, the Iranian Bam and Tunisian Deglet Noor. The differences of metabolome were investigated using proton nuclear magnetic resonance (1H NMR) spectroscopy combined with multivariate data analysis (MVDA). Principal Component Analysis (PCA) revealed clear separation between the date varieties. The Tunisian Deglet Noor demonstrated distinct cluster from the rest of the palm date samples based on the metabolite composition as shown by the pattern observed in Hierarchical Clustering Analysis (HCA) and PCA. Deglet Noor exhibited a significant higher level of sucrose (δ 5.40) and fructose (δ 4.16) in comparison with the other four varieties which can be associated with the distinctive sweet taste of this variety. Dates originated from Madinah and Tunisia exhibited a contrast manner in the amount of xylose and moisture content. These two aspects may contribute towards the soft texture of Tunisian dates. All Madinah dates were found to contain phenolic compounds which were well established as great antioxidant and anti-inflammatory agent. Ajwa dates exerted greater effect in inhibiting the generation of nitric oxide (NO) from the stimulated RAW264.7 cells at 95.37% inhibition. Succinic acid was suggested to have the most significant correlation with the trend of NO inhibitory shown by the selected date palm varieties.

SRJ09, a promising anticancer drug lead: Elucidation of mechanisms of antiproliferative and apoptogenic effects and assessment of in vivo antitumor efficacy.

SRJ09 (3,19-(2-bromobenzylidene)andrographolide), a semisynthetic andrographolide (AGP) derivative, was shown to induce G1 cell cycle arrest and eventually apoptosis in breast and colon cancer cell lines. The present investigation was carried out to elucidate the mechanisms cell cycle arrest and apoptosis and evaluate the in vivo antitumor activity of SRJ09. The in vitro growth inhibitory properties of compounds were assessed in colon (HCT-116) and breast (MCF-7) cancer cell lines. Immunoblotting was utilized to quantitate the protein levels in cells. The gene expressions were determined using reverse transcriptase PCR (RT-PCR). Pharmacokinetic investigation was carried out by determining SRJ09 levels in plasma of Balb/C mice using HPLC. In vivo antitumor activity was evaluated in athymic mice carrying HCT-116 colon tumor xenografts. SRJ09 displayed improved in vitro activity when compared with AGP by producing rapid cell killing effect in vitro. Its activity was not compromised in MES-SA/Dx5 multidrug resistant (MDR) cells expressing p-glycoprotein. Cells treated with SRJ09 (0.1-10µM) displayed increased p21 protein level, which corresponded with gene expression. Whereas CDK4 protein level and gene expression was suppressed. The treatment did not affect cyclin D1. Changes of these proteins paralleled G1 cell cycle arrest in both cell lines as determined by flow cytometry. Induction of apoptosis by SRJ09 in HCT-116 cells which occurred independent of p53 and bcl-2 was inhibited in the presence of caspase 8 inhibitor, implicating the extrinsic apoptotic pathway. A single dose (100mg/kg, i.p) of SRJ09 produced a plasma concentration range of 12-30.4µM. At 400mg/kg (q4dX3), it significantly retarded growth of tumor xenografts. The antitumor activity of SRJ09 is suggested mediated via the induction of p21 expression and suppression of CDK-4 expression without affecting cyclin D1 to trigger G1 arrest leading to apoptosis.

2-Benzoyl-6-benzylidenecyclohexanone analogs as potent dual inhibitors of acetylcholinesterase and butyrylcholinesterase.

In the present study, a series of 2-benzoyl-6-benzylidenecyclohexanone analogs have been synthesized and evaluated for their anti-cholinesterase activity. Among the forty-one analogs, four compounds (38, 39, 40 and 41) have been identified as lead compounds due to their highest inhibition on both AChE and BChE activities. Compounds 39 and 40 in particular exhibited highest inhibition on both AChE and BChE with IC50 values of 1.6µM and 0.6µM, respectively. Further structure-activity relationship study suggested that presence of a long-chain heterocyclic in one of the rings played a critical role in the dual enzymes' inhibition. The Lineweaver-Burk plots and docking results suggest that both compounds could simultaneously bind to the PAS and CAS regions of the enzyme. ADMET analysis further confirmed the therapeutic potential of both compounds based upon their high BBB-penetrating. Thus, 2-benzoyl-6-benzylidenecyclohexanone containing long-chain heterocyclic amine analogs represent a new class of cholinesterase inhibitor, which deserve further investigation for their development into therapeutic agents for cognitive diseases such as Alzheimer.

Discrimination and Nitric Oxide Inhibitory Activity Correlation of Ajwa Dates from Different Grades and Origin.

This study was aimed at examining the variations in the metabolite constituents of the different Ajwa grades and farm origins. It is also targeted at establishing the correlations between the metabolite contents and the grades and further to the nitric oxide (NO) inhibitory activity. Identification of the metabolites was generated using ¹H-NMR spectroscopy metabolomics analyses utilizing multivariate methods. The NO inhibitory activity was determined using a Griess assay. Multivariate data analysis, for both supervised and unsupervised approaches, showed clusters among different grades of Ajwa dates obtained from different farms. The compounds that contribute towards the observed separation between Ajwa samples were suggested to be phenolic compounds, ascorbic acid and phenylalanine. Ajwa dates were shown to have different metabolite compositions and exhibited a wide range of NO inhibitory activity. It is also revealed that Ajwa Grade 1 from the al-Aliah farm exhibited more than 90% NO inhibitory activity compared to the other grades and origins. Phenolic compounds were among the compounds that played a role towards the greater capacity of NO inhibitory activity shown by Ajwa Grade 1 from the al-Aliah farm.

Antinociceptive Effect of 3-(2,3-Dimethoxyphenyl)-1-(5-methylfuran-2-yl)prop-2-en-1-one in Mice Models of Induced Nociception.

The antinociceptive effects produced by intraperitoneal administration of a novel synthetic chalcone, 3-(2,3-dimethoxyphenyl)-1-(5-methylfuran-2-yl)prop-2-en-1-one (DMFP), were investigated in several mouse models of induced nociception. The administration of DMFP (0.1, 0.5, 1.0 and 5.0 mg/kg) produced significant attenuation on the acetic acid-induced abdominal-writhing test. It also produced a significant increase in response latency time in the hot-plate test and a marked reduction in time spent licking the injected paw in both phases of the formalin-induced paw-licking test. In addition, it was also demonstrated that DMFP exhibited significant inhibition of the neurogenic nociceptive response induced by intraplantar injections of capsaicin and glutamate. Moreover, the antinociceptive effect of DMFP in the acetic acid-induced abdominal-writhing test and the hot-plate test was not antagonized by pretreatment with a non-selective opioid receptor antagonist, naloxone. Finally, DMFP did not show any toxic effects and/or mortality in a study of acute toxicity and did not interfere with motor coordination during the Rota-rod test. Our present results show that DMFP exhibits both peripheral and central antinociceptive effects. It was suggested that its peripheral antinociceptive activity is associated with attenuated production and/or release of NO and various pro-inflammatory mediators, while central antinociceptive activity seems to be unrelated to the opioidergic system, but could involve, at least in part, an interaction with the inhibition of capsaicin-sensitive fibers and the glutamatergic system.

Anti-Diabetic Activity and Metabolic Changes Induced by Andrographis paniculata Plant Extract in Obese Diabetic Rats.

Andrographis paniculata is an annual herb and widely cultivated in Southeast Asian countries for its medicinal use. In recent investigations, A. paniculata was found to be effective against Type 1 diabetes mellitus (Type 1 DM). Here, we used a non-genetic out-bred Sprague-Dawley rat model to test the antidiabetic activity of A. paniculata against Type 2 diabetes mellitus (Type 2 DM). Proton Nuclear Magnetic Resonance (¹H-NMR) spectroscopy in combination with multivariate data analyses was used to evaluate the A. paniculata and metformin induced metabolic effects on the obese and obese-diabetic (obdb) rat models. Compared to the normal rats, high levels of creatinine, lactate, and allantoin were found in the urine of obese rats, whereas, obese-diabetic rats were marked by high glucose, choline and taurine levels, and low lactate, formate, creatinine, citrate, 2-oxoglutarate, succinate, dimethylamine, acetoacetate, acetate, allantoin and hippurate levels. Treatment of A. paniculata leaf water extract was found to be quite effective in restoring the disturbed metabolic profile of obdb rats back towards normal conditions. Thisstudy shows the anti-diabetic potential of A. paniculata plant extract and strengthens the idea of using this plant against the diabetes. Further classical genetic methods and state of the art molecular techniques could provide insights into the molecular mechanisms involved in the pathogenesis of diabetes mellitus and anti-diabetic effects of A. paniculata water extract.

Nitric oxide inhibitory activity and antioxidant evaluations of 2-benzoyl-6-benzylidenecyclohexanone analogs, a novel series of curcuminoid and diarylpentanoid derivatives.

A series of twenty-four 2-benzoyl-6-benzylidenecyclohexanone analogs were synthesized and evaluated for their nitric oxide inhibition and antioxidant activity. Six compounds (3, 8, 10, 17, 18 and 19) were found to exhibit significant NO inhibitory activity in LPS/IFN-induced RAW 264.7 macrophages, of which compound 10 demonstrated the highest activity with the IC50 value of 4.2 ± 0.2 µM. Furthermore, two compounds (10 and 17) displayed antioxidant activity upon both the DPPH scavenging and FRAP analyses. However, none of the 2-benzoyl-6-benzylidenecyclohexanone analogs significantly scavenged NO radical. Structure-activity comparison suggested that 3,4-dihydroxylphenyl ring is crucial for bioactivities of the 2-benzoyl-6-benzylidenecyclohexanone analogs. The results from this study and the reports from previous studies indicated that compound 10 could be a candidate for further investigation on its potential as a new anti-inflammatory agent.

Anti-proliferative effect and induction of apoptosis in androgen-independent human prostate cancer cells by 1,5-bis(2-hydroxyphenyl)-1,4-pentadiene-3-one.

Curcumin has poor in vivo absorption and bioavailability, highlighting a need for new curcumin analogues with better characteristics in these aspects. The aim of this study is to determine the anti-cancer properties of four selected curcumin analogues, on the cytotoxicity, proliferative and apoptotic effects on androgen-independent human prostate cancer cells (PC-3 and DU 145). Initial cytotoxicity screening showed MS17 has the highest cell inhibitory effect, with EC50 values of 4.4 ± 0.3 and 4.1 ± 0.8 µM, followed by MS13 (7.5 ± 0.1 and 7.4 ± 2.6 µM), MS49 (14.5 ± 1.2 and 12.3 ± 2.3 µM) and MS40E (28.0 ± 7.8 and 30.3 ± 1.9 µM) for PC-3 and DU 145 cells, respectively. Time-dependent analysis also revealed that MS13 and MS17 displayed a greater anti-proliferative effect than the other compounds. MS17 was chosen based on the high selectivity index value for further analysis on the morphological and biochemical hallmarks of apoptosis. Fluorescence microscopy analysis revealed apoptotic changes in both treated prostate cancer cells. Relative caspase-3 activity increased significantly at 48 h in PC-3 and 12 h in DU 145 cells. Highest enrichment of free nucleosomes was noted at 48 h after treatment with MS17. In conclusion, MS17 demonstrated anti-proliferative effect and induces apoptosis in a time and dose-dependent manner suggesting its potential for development as an anti-cancer agent for androgen-independent prostate cancer.

The Curcumin Analogue 1,5-Bis(2-hydroxyphenyl)-1,4-pentadiene-3-one Induces Apoptosis and Downregulates E6 and E7 Oncogene Expression in HPV16 and HPV18-Infected Cervical Cancer Cells.

In an effort to study curcumin analogues as an alternative to improve the therapeutic efficacy of curcumin, we screened the cytotoxic potential of four diarylpentanoids using the HeLa and CaSki cervical cancer cell lines. Determination of their EC50 values indicated relatively higher potency of 1,5-bis(2-hydroxyphenyl)-1,4-pentadiene-3-one (MS17, 1.03 ± 0.5 µM; 2.6 ± 0.9 µM) and 1,5-bis(4-hydroxy-3-methoxyphenyl)-1,4-pentadiene-3-one (MS13, 2.8 ± 0.4; 6.7 ± 2.4 µM) in CaSki and HeLa, respectively, with significantly greater growth inhibition at 48 and 72 h of treatment compared to the other analogues or curcumin. Based on cytotoxic and anti-proliferative activity, MS17 was selected for comprehensive apoptotic studies. At 24 h of treatment, fluorescence microscopy detected that MS17-exposed cells exhibited significant morphological changes consistent with apoptosis, corroborated by an increase in nucleosomal enrichment due to DNA fragmentation in HeLa and CaSki cells and activation of caspase-3 activity in CaSki cells. Quantitative real-time PCR also detected significant down-regulation of HPV18- and HPV16-associated E6 and E7 oncogene expression following treatment. The overall data suggests that MS17 treatment has cytotoxic, anti-proliferative and apoptosis-inducing potential in HPV-positive cervical cancer cells. Furthermore, its role in down-regulation of HPV-associated oncogenes responsible for cancer progression merits further investigation into its chemotherapeutic role for cervical cancer.

In vitro 3D colon tumor penetrability of SRJ09, a new anti-cancer andrographolide analog.

Limited tumor penetrability of anti-cancer drugs is recognized as one of the major factors that lead to poor anti-tumor activity. SRJ09 (3,19-(2-bromobenzylidene) andrographolide) has been identified as a lead anti-cancer agent for colon cancer. Recently, this compound was shown by us to be a mutant K-Ras binder. In this present study, the penetrability of SRJ09 through the DLD-1 colon cancer multicell layer (MCL) was evaluated. The amount of SRJ09 that penetrated through the MCL was quantitated by utilizing high performance liquid chromatography (HPLC). Histopathological staining was used to visualize the morphology of MCL. A chemosensitivity assay was performed to assess the anti-cancer activity of SRJ09 in DLD-1 cells. SRJ09 was able to penetrate through DLD-1 MCL and is inversely proportional with the MCL thickness. The flow rates for SRJ09 through MCL were 0.90 ± 0.20 µM/min/cm(2) and 0.56 ± 0.06 µM/min/cm(2) for days 1 and 5, respectively, which are better than doxorubicin. Histopathological examination revealed that the integrity of the DLD-1 MCL was retained and no visible damage was inflicted on the cell membrane, confirming the penetration of SRJ09 was by diffusion. Short term exposure (1 h) in DLD-1 cells demonstrated SRJ09 had IC50 of 41 µM which was approximately 4-folds lower than andrographolide, the parent compound of SRJ09. In conclusion, SRJ09 successfully penetrated through DLD-1 MCL by diffusion and emerged as a potential candidate to be developed as a clinically viable anti-colon cancer drug.

SRJ23, a new semisynthetic andrographolide derivative: in vitro growth inhibition and mechanisms of cell cycle arrest and apoptosis in prostate cancer cells.

PURPOSE: 3,19-(3-Chloro-4-fluorobenzylidene)andrographolide (SRJ23), a new semisynthetic derivative of andrographolide (AGP), exhibited selectivity against prostate cancer cells in the US National Cancer Institute (NCI) in vitro anti-cancer screen. Herein, we report the in vitro growth inhibition and mechanisms of cell cycle arrest and apoptosis induced by SRJ23. METHODS: 3-(4,5-Dimethythiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay was used in assessing in vitro growth inhibition of compounds against prostate cancer (PC-3, DU-145 and LNCaP) and mouse macrophage (RAW 264.7) cell lines. Flow cytometry was utilised to analyse cell cycle distribution, whereas fluorescence microscopy was performed to determine morphological cell death. DNA fragmentation and annexin V-fluorescein isothiocyanate (FITC)/propidium iodide (PI) flow cytometry were done to confirm apoptosis induced by SRJ23. Quantitation of cell cycle and apoptotic regulatory proteins were determined by immunoblotting. RESULTS: AGP and SRJ23 selectively inhibited the growth of prostate cancer cells compared with RAW 264.7 cells at low micromolar concentrations; however, SRJ23 was more potent. Mechanistically, SRJ23-treated PC-3 cells displayed down-regulation of cyclin-dependent kinase (CDK) 1 without affecting levels of CDK4 and cyclin D1. However, SRJ23 induced down-regulation of CDK4 and cyclin D1 but without affecting CDK1 in DU145 and LNCaP cell lines. DNA histogram analysis revealed that the SRJ23 induced G2/M in PC-3 cells but G1 arrest in DU-145 and LNCaP cells. Morphologically, both compounds induced predominantly apoptosis, which was further confirmed by DNA fragmentation and annexin V-FITC staining. The DNA fragmentation was inhibited in the presence of caspase 8 inhibitor (Z-IETD-FMK). Apoptosis was associated with an increase in caspase 8 expression and activation. This thought to have induced cleavage of Bid into t-Bid. Additionally, increased expression and activation of caspase 9 and Bax proteins were apparent, with a concomitant down-regulation of Bcl-2 protein. Similar apoptosis cascade of events was observed in SRJ23-treated DU145 and LNCaP cell lines. CONCLUSION: SRJ23 inhibited the growth of prostate cancer cells by inducing G2/M and G1 arrest via down-regulation of CDK1, and CDK4 and cyclin, respectively, and initiated caspase-8-mediated mitochondrial apoptosis. Taken together, these data support the potential of this compound as a new anti-prostate cancer agent.

Synthesis and sar study of diarylpentanoid analogues as new anti-inflammatory agents.

A series of ninety-seven diarylpentanoid derivatives were synthesized and evaluated for their anti-inflammatory activity through NO suppression assay using interferone gamma (IFN-γ)/lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages. Twelve compounds (9, 25, 28, 43, 63, 64, 81, 83, 84, 86, 88 and 97) exhibited greater or similar NO inhibitory activity in comparison with curcumin (14.7 ± 0.2 µM), notably compounds 88 and 97, which demonstrated the most significant NO suppression activity with IC50 values of 4.9 ± 0.3 µM and 9.6 ± 0.5 µM, respectively. A structure-activity relationship (SAR) study revealed that the presence of a hydroxyl group in both aromatic rings is critical for bioactivity of these molecules. With the exception of the polyphenolic derivatives, low electron density in ring-A and high electron density in ring-B are important for enhancing NO inhibition. Meanwhile, pharmacophore mapping showed that hydroxyl substituents at both meta- and para-positions of ring-B could be the marker for highly active diarylpentanoid derivatives.

Peripheral antinociception of a chalcone, flavokawin B and possible involvement of the nitric oxide/cyclic guanosine monophosphate/potassium channels pathway.

Previous studies have shown that systemic administration of 6'-hydroxy-2',4'-dimethoxychalcone (flavokawin B, FKB) exerts significant peripheral and central antinociceptive effects in laboratory animals. However, the mechanisms underlying these peripheral and central antinociceptive effects have yet to be elucidated. Therefore, the objective of the present study was to evaluate the participation of nitric oxide (NO)/cyclic guanosine monophosphate (cGMP)/potassium (K+) channels pathway in the peripheral antinociception induced by FKB. It was demonstrated that intraplantar (i.pl.) administration of FKB (150, 250, 375 and 500 µg/paw) resulted in dose-dependent peripheral antinociception against mechanical hyperalgesia in carrageenan-induced hyperalgesia test model in rats. The possibility of FKB having either a central or a systemic effect was excluded since administration of FKB into the right paw did not elicit antinociception in the contralateral paw. Furthermore, peripheral antinociception induced by FKB (500 µg/paw) was significantly reduced when L-arginine (25 µg/paw, i.pl.), Oxadiazolo[4,3-a]quinoxalin-1-one (ODQ; 50 µg/paw, i.pl.), glibenclamide (300 µg/paw, i.pl.), tetraethylammonium (300 µg/paw, i.pl.) and charybdotoxin (3 µg/paw, i.pl.) were injected before treatment. Taken together, our present data suggest that FKB elicits peripheral antinociception when assessed in the mechanical hyperalgesia induced by carrageenan. In addition, it was also demonstrated that this effect was mediated through interaction of the NO/cGMP/K+ channels signaling pathway.

A geranyl acetophenone targeting cysteinyl leukotriene synthesis prevents allergic airway inflammation in ovalbumin-sensitized mice.

Asthma is associated with increased pulmonary inflammation and airway hyperresponsiveness. The current use of corticosteroids in the management of asthma has recently raised issues regarding safety and lack of responsiveness in 5-10% of asthmatic individuals. The aim of the present study was to investigate the therapeutic effect of a non-steroidal small molecule that has cysteinyl leukotriene (cysLT) inhibitory activity, upon attenuation of allergic lung inflammation in an acute murine model. Mice were sensitized with ovalbumin (OVA) and treated with several intraperitoneal doses (100, 20, 2 and 0.2mg/kg) of 2,4,6,-trihydroxy-3-geranylacetophenone (tHGA). Bronchoalveolar lavage was performed, blood and lung samples were obtained and respiratory function was measured. OVA sensitization increased pulmonary inflammation and pulmonary allergic inflammation was significantly reduced at doses of 100, 20 and 2mg/kg with no effect at the lowest dose of 0.2mg/kg. The beneficial effects in the lung were associated with reduced eosinophilic infiltration and reduced secretion of Th2 cytokines and cysLTs. Peripheral blood reduction of total IgE was also a prominent feature. Treatment with tHGA significantly attenuated altered airway hyperresponsiveness as measured by the enhanced pause (Penh) response to incremental doses of methacholine. These data demonstrate that tHGA, a synthetic non-steroidal small molecule, can prevent acute allergic inflammation. This proof of concept opens further avenues of research and development of tHGA as an additional option to the current armamentarium of anti-asthma therapeutics.