Synthesis of 4,4-Disubstituted 3-Methylidenechroman-2-ones as Potent Anticancer Agents.

The synthesis of a new library of 4,4-disubstituted 3-methylidene-3,4-dihydro-2H-chroman-2-ones applying Horner-Wadsworth-Emmons methodology for the construction of an exo-methylidene moiety is reported. Corresponding 3-diethoxyphosphorylchroman-2-ones were synthesized in a three-step reaction sequence consisting of O-methylation of ethyl 2-diethoxyphosphoryl-3-oxoalkanoates, followed by reaction of the obtained 2-diethoxyphosphoryl-3-methoxy-2-alkenoates with phenols or 1-naphthol. The resulting 3-diethoxyphosphorylochromen-2-ones proved to be effective Michael acceptors in reactions with various Grignard reagents. Preliminary biological evaluations showed that many of the synthesized 3-methylidenechroman-2-ones possess very high cytotoxic activity against NALM-6 and HL-60 cancer cell lines (IC50 <1.0 µm) as well as high activity against the MCF-7 cancer cell line (IC50 <10 µm). Furthermore, two of the highly active 3-methylidenechroman-2-ones with geminal methyl and ethyl substituents at position 4 showed promising therapeutic indexes of 10 and 13 in tests against human umbilical vein endothelial cells (HUVECs).

Anticancer properties of new synthetic hybrid molecules combining naphtho[2,3-b]furan-4,9-dione or benzo[f]indole-4,9-dione motif with phosphonate subunit.

In this paper we report an efficient and general synthesis of substituted 3-diethoxyphosphorylnaphtho [2,3-b]furan-4,9-diones and 3-diethoxyphosphorylbenzo [f]indole-4,9-diones which integrate the natural 1,4-naphtalenedione scaffold, present in several anticancer agents with the phosphonate moiety. The cytotoxicity of such hybrid molecules was tested against two leukemia cell lines, HL-60 and NALM-6 and against a breast adenocarcinoma MCF-7 cell line. Selected compounds were also tested on normal human cells: HUVEC and MCF-10A. In general, naphthofuran-4,9-diones showed much higher cytotoxic activity (IC50 values below 10 µM) than benzoindole-4,9-diones. The most promising 2-(2-chlorophenyl)-3-diethoxyphosphorylnaphtho [2,3-b]furan-4,9-dione, with the highest cytotoxic activity in the MTT test, was chosen for further evaluation of its anticancer potential. This compound, tested on HL-60 and MCF-7 cells inhibited cell proliferation, generated DNA damage and induced apoptosis. The suggested mechanism of its cytotoxic activity was the generation of intracellular reactive oxygen species and the induction of mitochondrial membrane potential dissipation.

Opioid and Cannabinoid System in Food Intake.

Energy intake and expenditure are regulated by a complex network of neurochemical systems. The results of numerous studies have provided information about receptors involved, the sites of action within the brain and interactions between various systems, including opioid and cannabinoid, in regulation of energy balance. This review summarizes our present knowledge on the opioid and cannabinoid system appetite and satiety pathways. The involvement of the three main types of opioid receptors (MOR, DOR and KOR) and CB1 cannabinoid receptor, as well as the endogenous ligands of these receptors in food intake is documented. Finally, the use of opioid-cannabinoid system interactions as a new approach in the search for the next generation therapeutics controlling food intake disorders is discussed.

Anticancer properties of novel 4-methylene-1,2-diphenylpyrazolidin-3-ones.

The limited success of the currently used antitumor therapies is the driving force for organic chemists to seek new lead structures with anticancer potential. Two α-methylene-γ-lactams with an additional nitrogen atom in the lactam ring, 5-vinyl-1,2-diphenyl-4-methylenepyrazolidin-3-one (2a) and 5-phenyl-1,2-diphenyl-4-methylenepyrazolidin-3-one (2b) have been synthesized. Their anticancer activity was assessed in MCF-7 cells. Both compounds inhibited cell proliferation and induced DNA damage and apoptosis, with 2a being the more potent analog. Synergistic effects of 2a used in combination with known anticancer drugs, 5-fluorouracil, taxol, and oxaliplatin were evaluated. Compound 2a significantly enhanced the antitumor action of oxaliplatin and 5-fluorouracil, but not taxol.

Combined effects of anticancer drugs and new synthetic α-methylene-δ-lactones on MCF-7 cells.

The search for novel drug candidates is a priority goal for cancer therapy. Natural products isolated from plants are often used as valuable leads for the synthesis of analogs with simpler structure. Two synthetic α-methylene-δ-lactones with chroman-2-one skeleton, designated DL-3 and DL-5, exhibiting strong cytotoxic activity against several cancer cell lines, have been tested alone and in combination with well-known anticancer drugs, 5-fluorouracil, oxaliplatin, and taxol, in breast cancer MCF-7 cells. Parthenolide, a plant-derived α-methylene-γ-lactone, was used as a positive control. The effects on cell proliferation, DNA damage, and apoptosis induction were evaluated. Neither of the tested compounds significantly enhanced the effects produced by taxol, but a strong synergistic effect was observed with 5-fluorouracil and oxaliplatin. Only small differences between the actions of both α-methylene-δ-lactones were found. The synergistic effects produced by these compounds in MCF-7 cells were stronger as compared with parthenolide. Our findings show that simple and easy-to-obtain synthetic compounds with α-methylene-δ-lactone motif can potentiate the efficiency of anticancer drugs.

Design, synthesis and cytotoxic evaluation of 4-methylidenepyrazolidin-3-ones.

Three series of new 4-methylidenepyrazolidin-3-ones with various substitution patterns were synthesized and tested for the cytotoxic activity against two human leukemia cell lines NALM-6 and HL-60 as well as MCF-7 breast cancer cell line. Several obtained methylidenepyrazolidinones exhibited high cytotoxic activity with IC50 values below 10 µM, mainly against HL-60 leukemia cell line and two of them, 18d,e, displayed IC50 ≤ 5 µM, against all tested cell lines. Structure-activity relationship studies revealed that the presence of phenyl substituents on both ring nitrogen atoms and vinyl or phenyl substituents in position 5 are crucial for high activity. Selected methylidenepyrazolidinones were also tested on normal human umbilical vein endothelial cells (HUVEC) and pyrazolidinone 18a was found to be 5-fold more toxic against HL-60 than normal cells.

Immunomodulatory effects of endogenous and synthetic peptides activating opioid receptors.

The main role of endogenous opioid peptides is the modulation of pain. Opioid peptides exert their analgesic activity by binding to the opioid receptors distributed widely in the central nervous system (CNS). However, opioid receptors are also found on tissues and organs outside the CNS, including the cells of the immune system, indicating that opioids are capable of exerting additional effects in periphery. Morphine, which is a gold standard in the treatment of chronic pain, is well-known for its immunosuppressive effects. Much less is known about the immunomodulatory effects exerted by endogenous (enkephalins, endorphins, dynorphins and endomorphins) and synthetic peptides activating opioid receptors. In this review we tried to summarize opioid peptide-mediated modulation of immune cell functions which can be stimulatory as well as inhibitory.

Levels of bacterial endotoxin in air of animal houses determined with the use of gas chromatography-mass spectrometry and Limulus test.

Air samples were collected on glass fibre filters in 22 animal houses and 3 hay storage barns and examined for the presence of bacterial endotoxin with the Limulus (LAL) test and the gas chromatography-tandem mass spectrometry (GC-MSMS) technique, based on detection of 3-hydroxy fatty acids (3-OH-FAs) as chemical markers of the endotoxin lipopolysaccharide. The median concentrations of airborne endotoxin determined with LAL test in poultry houses, sheep sheds, piggeries, cow barns, and horse stables were respectively 62.49 microg/m3, 26.2 microg/m3, 3.8 microg/m3, 1.65 microg/m3, and 1.14 microg/m3, while those determined with the GC-MSMS technique were respectively 1.06 microg/m3, 7.91 microg/m3, 0.2 microg/m3, 0.31 microg/m3, and 1.42 microg/m3. The median concentrations of airborne endotoxin determined with LAL test and GC-MSMS technique in hay storage barns were much smaller, 0.09 microg/m3 and 0.03 microg/m3, respectively. The concentrations of airborne endotoxin (LPS) detected with GC-MSMS method in the air of sheep sheds were significantly greater than in all other examined facilities, while those detected in hay storage barns were significantly smaller than in all other examined facilities (p<0.05). The concentrations of airborne endotoxin determined with LAL test and GC-MSMS analysis exceeded in most of animal houses examined (91% by each method) the threshold limit value for airborne endotoxin of 0.1 microg/m3 proposed by various authors. A significant correlation (p<0.05) between the concentrations of endotoxin determined with the LAL and GC-MSMS techniques was found in the air samples collected in poultry houses and sheep sheds, but not in other examined facilities. 3-OH FAs with C14-C18 chains were predominant in the air of the facilities under study. A significant correlation (p<0.05) was found between the concentrations of endotoxin determined with LAL test and the amounts of 3-OH FAs with C14-C16 chains. In conclusion, endotoxin in the concentrations detected in this study may present a respiratory hazard to both humans and livestock animals.

Assessment of microbial exposure risks from handling of biofuel wood chips and straw--effect of outdoor storage.

Handling of biofuels may release dust particles containing high concentrations of Hazardous microorganisms, thus representing a potential occupational health problem. We analysed the microbial dustiness of baled straw (cultivated both conventionally and ecologically) and of wood chips from piles that had been stored outdoors for up to 11 months by using total spore counting, cultivation, and measuring of endotoxin and chemical markers of fungal biomass, lipopolysaccharide, and peptidoglycan. The bacterial dustiness of straw was much greater than of wood chips whereas the fungal dustiness did not differ much. In general, samples taken from the inner part of each biofuel material were dustier than samples taken from the surface, except for fungal and bacterial biomass in wood chips and total fungi and fungal biomass in ecological straw. A considerable increase of bacterial dustiness occurred during storage over summer. Dust from ecological straw contained considerably less of bacterial components than from conventional straw and, in addition, exhibited a less pronounced increase upon storage over summer. In summary, biofuels represent sustainable energy resources of growing economic importance but may at the same time pose significant health problems. We found that storage of biofuels outdoors over summer increased the microbiological dustiness and should therefore be avoided, and that ecological straw contained less of microbe-containing dust than conventional straw and should be preferred since it reduces the exposure to harmful microbiological agents.