ABSTRACT
Objective: To evaluate chemical compositions, antioxidant and wound healing properties of Algerian Artemisia absinthium essential oil.Methods: The chemical composition of the essential oil from Artemisia absinthium was analyzed by a combination of GC-FID and GC/MS. The antioxidant capacities including the total antioxidant capacity, DPPH? and ABTS+? scavenging capacities were measured. The wound healing potential was assessed by the excision wound model of rats. The wounds were treated daily with an ointment prepared with two concentrations (5％ and 10％) of Artemisia absinthium essential oil. The percentage of wound contraction was determined and wound healing was also evaluated by histological examination of the healed skin. Results: The main component of Artemisia absinthium essential oil was camphor (48％) followed by chamazulene (10％) that was responsible for the dark blue color of the oil. Artemisia absinthium essential oil exhibited moderate antioxidant activity compared with BHT and Trolox. All preparations showed significant effects on wound contraction and the ointment prepared with 10％ of essential oil was effective as the reference drug Cicatryl. Conclusions: The essential oil of Artemisia absinthium shows moderate antioxidant activity. The 10％ ointment enhances skin wound re-epithelialization and speeds up the healing process. The essential oil of Artemisia absinthium may be used as an alternative drug for wound healing.
ABSTRACT
The p42/p44 mitogen-activated protein (MAP) kinase is stimulated by various mitogenic stimuli, and its sustained activation is necessary for cell cycle G(1) progression and G(1)/S transition. G(1) progression and G(1)/S transition also depend on sequential cyclin-dependent kinase (CDK) activation. Here, we demonstrate that MAP kinase inhibition leads to accumulation of the CDK inhibitor p27(Kip1) in NIH 3T3 cells. Blocking the proteasome-dependent degradation of p27(Kip1) impaired this accumulation, suggesting that MAP kinase does not act on p27(Kip1) protein synthesis. In the absence of extracellular signals (growth factors or cell adhesion), genetic activation of MAP kinase decreased the expression of p27(Kip1) as assessed by cotransfection experiments and by immunofluorescence detection. Importantly, MAP kinase activation also decreased the expression of a p27(Kip1) mutant, which cannot be phosphorylated by CDK2, suggesting that MAP kinase-dependent p27(Kip1) regulation is CDK2-independent. Accordingly, expression of dominant-negative CDK2 did not impair the down-regulation of p27(Kip1) induced by MAP kinase activation. These data demonstrate that the MAP kinase pathway regulates p27(Kip1) expression in fibroblasts essentially through a degradation mechanism, independently of p27(Kip1) phosphorylation by CDK2. This strengthens the role of this CDK inhibitor as a key effector of G(1) growth arrest, whose expression can be controlled by extracellular stimuli-dependent signaling pathways.
Subject(s)
CDC2-CDC28 Kinases , Cell Cycle Proteins/metabolism , Cyclin E/physiology , Cyclin-Dependent Kinases/physiology , Mitogen-Activated Protein Kinase 1/physiology , Mitogen-Activated Protein Kinases/physiology , Protein Serine-Threonine Kinases/physiology , Tumor Suppressor Proteins , 3T3 Cells , Animals , Cyclin-Dependent Kinase 2 , Cyclin-Dependent Kinase Inhibitor p27 , Cysteine Endopeptidases/physiology , Enzyme Activation , Mice , Mitogen-Activated Protein Kinase 3 , Mitogen-Activated Protein Kinase Kinases/physiology , Multienzyme Complexes/physiology , Phosphorylation , Proteasome Endopeptidase ComplexABSTRACT
Production of lactic acid from date juice by fermentation has been studied using Lactobacillus casei subsp. rhamnosus as the producer organism. The optimum substrate concentration, expressed in its glucose content, was 60 g l(-1). Various nitrogen sources were compared with yeast extract in terms of their efficiency for lactic acid production. None of these nitrogen sources gave lactic acid concentrations as high as that obtained with yeast extract. As yeast extract supplementation was not economically attractive, different proportions of (NH4)2SO4 and yeast extract were used. When the elemental nitrogen ratio of(NH4)2SO4 to yeast extract was 4:1, the substrate use and efficiency of lactic acid production were the same as in date juice supplemented with 20 g l(-1) yeast extract (0:5).
