Cytotoxic mycoepoxydiene derivatives from an endophytic fungus Phomopsis sp. isolated from Hydnocarpus anthelminthicus

Mycoepoxydiene ( 1) and derivatives, deacetylmycoepoxydiene ( 2) and 2,3-dihydromycoepoxydiene ( 3), were isolated from a broth extract of the endophytic fungus, phomopsis sp., which was isolated from a Thai medicinal plant, Hydnocarpus anthelminthicus. Compounds 1 and 2 exhibited potent cytotoxic activity, while a dihydro derivative 3 was inactive. The present work suggests that the alpha,beta-unsaturated lactone moiety in mycoepoxydienes might be responsible for the cytotoxicity.     

Sesamin Stimulates Osteoblast Differentiation Through p38 and ERK1/2 MAPK Signaling Pathways

ABSTRACT: BACKGROUND: Osteoporosisis a worldwide health problem predominantly affecting post-menopausal women. Therapies aimed at increasing bone mass in osteoporetic patients lag behind comparable investigation of therapeutic strategies focusing on the bone resorption process. Sesamin, a major lignan compound found in Sesamun indicum Linn., has a variety of pharmacological effects, though its activity on bone cell function is unclear. Herein we examine the effect of this lignan on osteoblast differentiation and function. METHOD: Cell cytotoxicity and proliferative in hFOB1.19 were examined by MTT and alamar blue assay up to 96 hour of treatment. Gene expression of COL1, ALP, BMP-2, Runx2, OC, RANKL and OPG were detected after 24 hour of sesamin treatment. ALP activity was measured at day 7, 14 and 21 of cultured. For mineralized assay, ADSCs were cultured in the presence of osteogenic media supplement with or without sesamin for 21 days and then stain with Alizarin Red S staining. MAPK signaling pathway activation was observed by using western blotting. RESULTS: Sesamin promoted the expression COL1, ALP, OCN, BMP-2 and Runx2 in hFOB1.19. On the other hand, sesamin was able to up-regulate OPG and down-regulate RANKL gene expression. ALP activity also significantly increased after sesamin treatment. Interestingly, sesamin induced formation of mineralized nodules in adipose derived stem cells (ADSCs) as observed by Alizarin Red S staining; this implies that sesamin has anabolic effects both on progenitor and committed cell stages of osteoblasts. Western blotting data showed that sesamin activated phosphorylation of p38 and ERK1/2 in hFOB1.19. CONCLUSIONS: The data suggest that sesamin has the ability to trigger osteoblast differentiation by activation of the MAPK signaling pathway (p38 and ERK) and possibly indirectly regulate osteoclast development via the expression of OPG and RANKL in osteoblasts. Therefore, sesamin may be a promising phytochemical that could be developed for osteoporotic therapy.     

Involvement of phospholipase D in regulating expression of anti-microbial peptide human beta-defensin-2

Human beta-defensin expression correlates with differentiation in oral epithelium, and calcium ion, an important regulator of epithelial differentiation, plays a critical role in regulation of human beta-defensin-2 (hBD-2) mRNA expression. Phospholipase D (PLD) also regulates epithelial differentiation. Therefore, we examined the role of PLD in hBD-2 up-regulation by cell wall extract of Fusobacterium nucleatum and phorbol 12-myristate 13-acetate (PMA), two known hBD-2 activators. We found that hBD-2 mRNA up-regulation in human gingival epithelial cells (HGECs) by these two activators was mediated by PLD activation and blocked by ethanol and 1-butanol, PLD inhibitors. PLD activity was induced by stimulation with these two activators, and phosphatidic acid (PA), a product generated from the PLD enzymatic activity, was detected in stimulated HGECs. Dioctanoyl PA commonly used for PA induced hBD-2 mRNA expression. mRNAs for PLD1 alpha and beta splice variants as well as PLD1 protein were constitutively expressed, whereas mRNA and protein for PLD2 were expressed at much lower levels than those for PLD1. Moreover, pre-treatment with (+/-)-propanolol, an inhibitor of phosphatidic acid phosphohydrolases that are the downstream signaling molecules in the PLD pathway, significantly blocked hBD-2 mRNA induction by PMA in a dose-dependent manner. In conclusion, these findings indicate the involvement of PLD activation in hBD-2 up-regulation in HGECs, which correlates with the state of epithelial differentiation.     

Effectiveness of a model of risky sexual behavior prevention among adolescent boys in Thailand

The objectives of this study were to identify predictable factors affecting risky sexual behavior and to evaluate the effectiveness of a risky sexual behavior prevention program among boys one and two months after the program. The Information-Motivation-Behavioral skills (IMB) model program was carried out among 74 adolescent boys aged 10-13 years and 74 of their parents in Phitsanulok Province, Thailand. Repeated analysis was employed to analyze the program's effectiveness. After the program, mean scores for comfort in talking about sex, self-efficacy, and skills in condom use increased significantly (p<0.05), and mean scores regarding knowledge about sexually transmitted infections and skills in decision making decreased significantly (p<0.05) compared to baseline. Boys participating in this program improved their condom use skills and comfort talking about sex at two months follow-up (t=3.82, p<0.001; t=3.10, p=0.003, respectively). These results provided evidence for applicability of a prevailing theory-based intervention within the local cultural context.     

Radical scavenging and antioxidant activities of isocoumarins and a phthalide from the endophytic fungus Colletotrichum sp

Five known isocoumarins, monocerin (1), derivative 2, and fusarentin derivatives 3-5, and a new phthalide (6) were isolated from the endophytic fungus Colletotrichum sp. 2 selectively exhibited cytotoxic activity toward the HepG2 cell line. Compounds 2 and 4 scavenged 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radicals (IC(50) values of 23.4 and 16.4 μM, respectively) and inhibited superoxide anion radical formation (IC(50) values of 52.6 and 4.3 μM, respectively). The C-7 hydroxyl group in 2 and 4 might be important for radical scavenging activities. Isocoumarins 1-3 and phthalide 6 showed potent antioxidant activity.     

Ethanolic extract of fermented Thunb induces human leukemic HL-60 and Molt-4 cell apoptosis via oxidative stress and a mitochondrial pathway

Houttuynia cordata Thunb (HCT) is a medicinal plant of the Saururaceae family which features antimutagenic and antiviral properties. For extraction, the whole plants were fermented or non-fermented with yeast and ethanol then the whole plants were dried, ground and extracted with 95% ethanol or water. The aims of this study were to compare cytotoxic effects, apoptosis induction, and mechanism(s) with the ethanolic and water extracts of fermented and non-fermented HCT. Cytotoxicity was assessed using the MTT assay in human leukemic HL-60, Molt-4 and peripheral blood mononuclear cells (PBMCs). Apoptotic death was characterized by staining with propidium iodide and examined under a fluorescence microscope. Peroxide radical production and reduction of mitochondrial transmembrane potential (MTP) were determined using 2',7'-dichlorohydrofluorescein diacetate and 3,3'-dihexyloxacarbocyanine iodide and flow cytometry, respectively. The expression of caspase-9 was identified by immunoblotting. The ethanolic extract of fermented HCT was cytotoxic to HL-60 >Molt- 4 > PBMCs, to a greater extent than the non-fermented preparation and the number of apoptotic cells was higher. The alcoholic (fermented) extract produced more radicals than the non-fermented in HL-60 cells but the converse was observed in Molt-4 cells. Reduction of MTP was found in HL-60 and Molt-4 cells treated with the alcoholic (fermented) extract and caspase-9 was cleaved dose-dependently in both cells. In conclusion, the alcoholic extract of fermented HCT was more toxic to human leukemic cells than the non-fermented and both cell lines underwent apoptosis via oxidative stress and a mitochondrial pathway.     

Comparison of glucose derivatives effects on cartilage degradation

Background  

Glucosamine (GlcN) is a well-recognized candidate for treatment of osteoarthritis. However, it is currently used in derivative forms, such as glucosamine-hydrochloride (GlcN-HCl) or glucosamine sulfate (GlcN-S). However, the molecular mode of action remains unclear. In this study, we compared the effects of Glucose (Glc), Glucuronic acid (GlcA), Glucosamine hydrochloride (GlcN-HCl) and Glucosamine sulfate (GlcN-S) on cartilage degradation.     

Chondroitin sulfate B and heparin mediate adhesion of Penicillium marneffei conidia to host extracellular matrices

Penicilliosis is a disseminated infection in immunocompromised individuals caused by the dimorphic fungus, Penicillium marneffei. Very little is known about its route of infection, however, it is thought that initial infection occurs through inhalation of conidia. We investigated the role played by various extracellular matrix glycosaminoglycans (GAGs) in the initial adherence of P. marneffei conidia using a direct adhesion assay. GAGs were further used to block the binding of fungal spores to human lung epithelial cells and highly sulfated GAGs were tested for their inhibitory effects owing to their degree of sulfation. Our results demonstrated high levels of conidial adhesion to chondroitin sulfate B, heparin and highly sulfated chitosan (CP-3). No direct adherence was observed to immobilized chondroitin sulfate (CS) A, CSC, CSD and hyaluronic acid, as well as chitosans with low sulfate content. The results suggested that P. marneffei conidia bind to iduronic acid (IdoA) of the polysaccharide chains. Involvement of negatively charged sulfate groups in adhesion was also indicated. Furthermore, significant inhibition of conidial adherence to A549 cells was observed in the presence of CSB, heparan sulfate (HS), heparin and CP-3. It was further demonstrated that GAGs can affect the adhesion of conidia to fibronectin and laminin, glycoproteins that have previously been implicated as adhesive receptors for fungal conidia. CSB and HS could partially inhibit the adhesion of fungal conidia to laminin and fibronectin implying that conidia can weakly interact with the IdoA GAG-binding domain(s) of these molecules. The data indicated that, in addition to fibronectin and laminin, IdoA-containing GAGs may play an important role in fungal adherence to the surface of human lung epithelium.