Toxicity assessments of chalcone and some synthetic chalcone analogues in a zebrafish model

[[abstract]]The aim of this study was to investigate the in vivo toxicities of some novel synthetic chalcones. Chalcone and four chalcone analogues 1a–d were evaluated using zebrafish embryos following antibody staining to visualize their morphological changes and muscle fiber alignment. Results showed that embryos treated with 3'-hydroxychalcone (compound 1b) displayed a high percentage of muscle defects (96.6%), especially myofibril misalignment. Ultrastructural analysis revealed that compound 1b-treated embryos displayed many muscle defect phenotypes, including breakage and collapse of myofibrils, reduced cell numbers, and disorganized thick (myosin) and thin (actin) filaments. Taken together, our results provide in vivo evidence of the myotoxic effects of the synthesized chalcone analogues on developing zebrafish embryos.[[incitationindex]]SCI[[booktype]]電子

Immunocytochemical Studies on Lipid Droplet-Surface Proteins in Adrenal Cells

Perilipin and ADRP, located on the surface of intracellular lipid droplets, are proposed to be involved in adipocyte lipid metabolism. The aim of the present study was to investigate the effect of PKA and PKC activities on the distribution of perilipin and ADRP in primary cultured adrenal cells, and the role of ERK in PMA- and calphostin C- induced steroidogenesis. Immunofluorescence staining indicated that in addition to p160, a capsular protein of steroidogenic lipid droplets, perilipin and ADRP were localized on the lipid droplet surface. Stimuli such as activation of PKA by db cAMP or inhibition of PKC by calphostin C, which increase corticosterone synthesis in various magnitudes, caused detachment of p160 and perilipin, but not ADRP, from the lipid droplet surface. Activation of PKC by PMA induced increase in corticosterone synthesis, however, it did not affect the distribution of perilipin, p 160, or ADRP on the lipid droplet surface, suggesting the presence of mechanisms for promoting sterodiogensis other than causing detachment of lipid droplet surface proteins. We further demonstrated that ERK pathway was involved in PMA -induced steroidogenesis, since PD98059, specific inhibitor of MFK, blocked the increases in steroidogenesis and phosphorylation of ERK caused by PMA, but not by cAMP-PKA. These data indicate that p160, perilipin, and ADRP were all located on the lipid droplet surface in rat adrenal cells. On the basis of its non-responsiveness to lipolytic stimulation, ADRP may be a structural protein of the lipid droplet surface, whereas their immediate response to lipolytic stimuli suggest that perilipin and p 160 are functional proteins. PKC regulates adrenal steroidogenesis through ERK cascade, whereas PKA pathway does not involve ERK

Development and Testing of X-Ray Imaging-Enhanced Poly-L-Lactide Bone Screws.

Nanosized iron oxide particles exhibit osteogenic and radiopaque properties. Thus, iron oxide (Fe3O4) nanoparticles were incorporated into a biodegradable polymer (poly-L-lactic acid, PLLA) to fabricate a composite bone screw. This multifunctional, 3D printable bone screw was detectable on X-ray examination. In this study, mechanical tests including three-point bending and ultimate tensile strength were conducted to evaluate the optimal ratio of iron oxide nanoparticles in the PLLA composite. Both injection molding and 3D printing techniques were used to fabricate the PLLA bone screws with and without the iron oxide nanoparticles. The fabricated screws were implanted into the femoral condyles of New Zealand White rabbits. Bone blocks containing the PLLA screws were resected 2 and 4 weeks after surgery. Histologic examination of the surrounding bone and the radiopacity of the iron-oxide-containing PLLA screws were evaluated. Our results indicated that addition of iron oxide nanoparticles at 30% significantly decreased the ultimate tensile stress properties of the PLLA screws. The screws with 20% iron oxide exhibited strong radiopacity compared to the screws fabricated without the iron oxide nanoparticles. Four weeks after surgery, the average bone volume of the iron oxide PLLA composite screws was significantly greater than that of PLLA screws without iron oxide. These findings suggested that biodegradable and X-ray detectable PLLA bone screws can be produced by incorporation of 20% iron oxide nanoparticles. Furthermore, these screws had significantly greater osteogenic capability than the PLLA screws without iron oxide

Okadaic Acid, a Bioactive Fatty Acid from Halichondria okadai, Stimulates Lipolysis in Rat Adipocytes: The Pivotal Role of Perilipin Translocation

Lipid metabolism in visceral fat cells is correlated with metabolic syndrome and cardiovascular diseases. Okadaic-acid, a 38-carbon fatty acid isolated from the black sponge Halichondria okadai, can stimulate lipolysis by promoting the phosphorylation of several proteins in adipocytes. However, the mechanism of okadaic acid-induced lipolysis and the effects of okadaic acid on lipid-droplet-associated proteins (perilipins and beta-actin) remain unclear. We isolated adipocytes from rat epididymal fat pads and treated them with isoproterenol and/or okadaic acid to estimate lipolysis by measuring glycerol release. Incubating adipocytes with okadaic acid stimulated time-dependent lipolysis. Lipid-droplet-associated perilipins and beta-actin were analyzed by immunoblotting and immunofluorescence, and the association of perilipin A and B was found to be decreased in response to isoproterenol or okadaic acid treatment. Moreover, okadaic-acid treatment could enhance isoproterenol-mediated lipolysis, whereas treatment of several inhibitors such as KT-5720 (PKA inhibitor), calphostin C (PKC inhibitor), or KT-5823 (PKG inhibitor) did not attenuate okadaic-acid-induced lipolysis. By contrast, vanadyl acetylacetonate (tyrosine phosphatase inhibitor) blocked okadaic-acid-dependent lipolysis. These results suggest that okadaic acid induces the phosphorylation and detachment of lipid-droplet-associated perilipin A and B from the lipid droplet surface and thereby leads to accelerated lipolysis

Hinokitiol Exerts Anticancer Activity through Downregulation of MMPs 9/2 and Enhancement of Catalase and SOD Enzymes: In Vivo Augmentation of Lung Histoarchitecture

Melanoma is extremely resistant to chemotherapy and the death rate is increasing hastily worldwide. Extracellular matrix promotes the migration and invasion of tumor cells through the production of matrix metalloproteinase (MMP)-2 and -9. Evidence has shown that natural dietary antioxidants are capable of inhibiting cancer cell growth. Our recent studies showed that hinokitiol, a natural bioactive compound, inhibited vascular smooth muscle cell proliferation and platelets aggregation. The present study is to investigate the anticancer efficacy of hinokitiol against B16-F10 melanoma cells via modulating tumor invasion factors MMPs, antioxidant enzymes in vitro. An in vivo mice model of histological investigation was performed to study the patterns of elastic and collagen fibers. Hinokitiol inhibited the expression and activity of MMPs-2 and -9 in B16-F10 melanoma cells, as measured by western blotting and gelatin zymography, respectively. An observed increase in protein expression of MMPs 2/9 in melanoma cells was significantly inhibited by hinokitiol. Notably, hinokitiol (1–5 μM) increased the activities of antioxidant enzymes catalase (CAT) and superoxide dismutase (SOD) from the reduction in melanoma cells. Also, hinokitiol (2–10 µM) concentration dependently reduced in vitro Fenton reaction induced hydroxyl radical (OH·) formation. An in vivo study showed that hinokitiol treatment increased elastic fibers (EF), collagens dispersion, and improved alveolar alterations in the lungs of B16/F10 injected mice. Overall, our findings propose that hinokitiol may be a potent anticancer candidate through down regulation of MMPs 9/2, reduction of OH· production and enhancement of antioxidant enzymes SOD and CAT

Lycopene Inhibit IMQ-Induced Psoriasis-Like Inflammation by Inhibiting ICAM-1 Production in Mice

Lycopene is the most abundant carotenoid in tomatoes, which has been identified to have the properties of anti-inflammation in addition to the capability to inhibit the expression of adhesion molecules. Intercellular adhesion molecules play a critical role in the pathogenesis of psoriasis. Here, we report that the topical use of a lycopene decreased imiquimod (IMQ)-induced psoriasis-like inflammatory responses, the progress of which was based on adhesion molecules. In vitro analysis showed that lycopene decreased keratinocyte and monocyte adhesion. Evidence suggests that intercellular adhesion molecule-1 (ICAM-1) is a main mediator of psoriasis pathogenesis. Therefore, it will be interesting to investigate the factors that contribute to the lycopene-mediated inhibition of ICAM-1 expression in psoriasis. We expect that lycopene will with potential value in the treatment of psoriasis

A typical example of the histologic image at the screw/bone interface 4 weeks after implanting the screws.

<p>The leached debris of the nano-Fe₃O₄/poly-L-lactide (PLLA) composite was surrounded by newly formed bone and bone cells (black arrow). BC: bone cell; BV: blood vessel; CT: connective tissue; DB: leached debris; MB: mature bone; NB: new bone. Scale bar, 50 μm.</p

Histologic examination of bone tissue at the screw/bone interface 2 weeks after implanting the screws.

<p>Neat poly-L-lactide (PLLA) screws were fabricated by injection molding (a) and 3D printing (c) methods. Screws made of PLLA mixed with 20% Fe₃O₄ nanoparticles fabricated by injection molding (b) and 3D printing (d). New bone (black arrows) was visible between more of the threads and occupied a greater area with the 20% nano-Fe₃O₄/PLLA screw compared to the neat PLLA screw. Scale bar, 1.0 mm.</p

Images of the four fabricated poly-L-lactide (PLLA) bone screws.

<p>The screws containing 0% (a and c) and 20% (w/w) Fe₃O₄ nanoparticles (b and d). Injection molding (a and b) and 3D printing (c and d) methods were used to produce the screws.</p