No abstract available.
Pneumonia* ; Squalene

No abstract available.
Pneumonia* ; Squalene*

Squalen, a compound detected in olive oil, had an activity against coloileal cancer due to azoxymethan in rats and lung cancer due to nitrosamin in mice. Squalen is a mediate substance in biosynthesis of mevaloat/cholesterol. Squalen is synthetised by catalysis squalen syntherase but it inhibits this enzyme which lead the reverse inhibition of HMG-CoA reductase to reduce the first stage of cholesterol synthesis. The more important outcome was that squalen inhibits protein transferees, which is an enzyme that is necessary for farnesrylization of rasprotein causing cancer
Squalene ; neoplasms

Triterpenoids are a class of natural products of great commercial value that are widely used in pharmaceutical, health care and cosmetic industries. The biosynthesis of triterpenoids relies on the efficient synthesis of squalene epoxide, which is synthesized from the NADPH dependent oxidation of squalene catalyzed by squalene epoxidase. We screened squalene epoxidases derived from different species, and found the truncated squalene epoxidase from Rattus norvegicus (RnSETC) showed the highest activity in engineered Escherichia coli. Further examination of the effect of endogenous cytochrome P450 reductase like (CPRL) proteins showed that overexpression of NADH: quinone oxidoreductase (WrbA) under Lac promoter in a medium-copy number plasmid increased the production of squalene epoxide by nearly 2.5 folds. These results demonstrated that the constructed pathway led to the production of squalene epoxide, an important precursor for the biosynthesis of triterpenoids.
Animals ; Escherichia coli/genetics* ; NADPH-Ferrihemoprotein Reductase ; Protein Engineering ; Rats ; Repressor Proteins ; Squalene ; Squalene Monooxygenase/genetics*

No abstract available.
Foreign Bodies* ; Foreign-Body Reaction ; Granuloma ; Granuloma, Foreign-Body* ; Squalene*

Exogenous lipoid pneumonia is an uncommon disease that's caused by aspirating lipid formulations. Squalene, obtained from shark liver oil, is one of the causative agent and this is commonly used by some Koreans as a health promoting medication. We report here on a case of exogenous lipoid pneumonia that developed after ingestion of squalene capsules. The case showed milky BAL fluid and multiple pulmonary consolidations.
Bronchoalveolar Lavage Fluid ; Capsules ; Eating ; Liver ; Pneumonia ; Sharks ; Squalene

Squalene is widely used in pharmaceutical, nutraceutical, cosmetics and other fields because of its strong antioxidative, antibacterial and anti-tumor activities. In order to produce squalene, a gene ispA encoding farnesyl pyrophosphate synthase was overexpressed in a previously engineered Escherichia coli strain capable of efficiently producing terpenoids, resulting in a chassis strain that efficiently synthesizes triterpenoids. Through phylogenetic analysis, screening, cloning and expression of squalene synthase derived from different prokaryotes, engineered E. coli strains capable of efficiently producing squalene were obtained. Among them, squalene produced by strains harboring squalene synthase derived from Thermosynechococcus elongatus and Synechococcus lividus reached (16.5±1.4) mg/g DCW ((167.1±14.3) mg/L broth) and (12.0±1.9) mg/g DCW ((121.8±19.5) mg/L broth), respectively. Compared with the first-generation strains harboring the human-derived squalene synthase, the squalene synthase derived from T. elongatus and S. lividus remarkably increased the squalene production by 3.3 times and 2.4 times, respectively, making progress toward the cost-effective heterologous production of squalene.
Cloning, Molecular ; Escherichia coli/genetics* ; Humans ; Phylogeny ; Squalene ; Synechococcus

Triterpenoids are one of the most diverse compounds in plant metabolites, and they have a wide variety of physiological activities and are of important economic value. Oxidosqualene cyclases catalyze the cyclization of 2, 3-oxidosqualene to generate different types of sterols and plant triterpenoids, which is of great significance to the structural diversity of natural products. However, the mechanism of the diversified cyclization of 2, 3-oxidosqualene catalyzed by oxidosqualene cyclases remains unclear. This review summarized the research progress of oxidosqualene cyclases from the aspects of catalytic function, molecular evolutionary relationship between genes and proteins, protein structure, molecular simulation and molecular calculations, which may provide a reference for protein engineering and metabolic engineering of triterpene cyclase.
Intramolecular Transferases/metabolism* ; Metabolic Engineering ; Plants/genetics* ; Squalene/chemistry* ; Triterpenes

BACKGROUND: A allergic contact dermatitis has been increasing in the world. The first choice of treatment for the allergic contact dermatitis is topical steroids, but application of topical steroids may lead to many side effects. Physiogel(R) cream, made of ceramide, triglyceride, squalene and others is a moisturizer without any fragnance or preservatives which has effects of normalizing the damaged skin barrier and soothing troubled skin. OBJECTIVES: We carried out this study to evaluate the effects of the Physiogel(R) cream in the treamemt of the allergic contact dermatitis. METHODS: Among the patients clinically suspected to have allergic contact dermatitis due to fragnance or perservatives, patients already diagnosed with allergic contact dermatitis were included. On the skin lesions of the right side of individual patients the Physiogel(R) cream was applied twice a day. No topical agents were applied to the lesions of the left side. Two weeks later the clinical improvement of skin lesions was compared. RESULTS: In fourteen (61%) out of 23 patients the Physiogel(R) cream-applied lesions showed significant clinical improvement compared with the control lesions. In cases of atopic dermatitis or seborrheic dermatitis, the ratio of patients in whom the Physiogel(R) cream was efficacious, was 80% or 70% respectively. The skin lesions of all patients of 2nd and 3rd decades were significantly improved by the Physiogel(R) cream. In patients whose skin lesions were not responsive to the Physiogel(R) cream, patch test results showed the highest positive response rate against nickel (20%) and formaldehyde (20%). CONCLUSION: Physiogel(R) cream could be used as well as topical steroids in the treatment of allergic contact dermatitis reducing the risk of side effects due to long-term use of topical steroids.
Dermatitis, Allergic Contact* ; Dermatitis, Atopic ; Dermatitis, Seborrheic ; Formaldehyde ; Humans ; Nickel ; Patch Tests ; Skin ; Squalene ; Steroids ; Triglycerides

PURPOSE: To describe the HRCT and pathologic findings of squalene-induced lipoid pneumonia in rabbits. MATERIALS AND METHODS: Three ml of squalene was instilled into the trachea between the second and the third tracheal ring in 16 rabbits. Serial HRCT scans were obtained on day 4 (n=8), at 1 week (n=7), 2 weeks (n=1), 4 weeks(n=1), 6 weeks (n=2) and 20 weeks (n=1) after squalene instillation. With sacrifice of the rabbits pathology was reviewed at 1 week (n=3), 4 weeks (n=3), and 6 weeks (n=4) after CT scans. RESULTS: Lipoid pneumonia was induced in 8 rabbits; lesions were distributed mainly in the dependent posterior lung. On serial HRCT scans, airspace consolidation, as seen on an air-bronchogrm, and nodular opacities were early findings; these gradually diminshed and with time were replaced by nodular & linear opacities. Histologically, pulmonary fibrosis appeared one week after squalene instillation and progressed over time. Alveolar septal thickening and cuboidal change of the alveolar lining epithelium were more prominent at week 6. CONCLUSION: The early change of squalene-induced lipoidpneumonia in rabbits is the proliferation of intraalveolar macrophage, which is responsible for air-space consolidation with air-bronchograms on HRCT. Nodular and linear opacities on HRCT are due to the appearance of pulmonary fibrosis one week after squalene instillation, and its subsequent progression.
Animals ; Epithelium ; Lung ; Macrophages ; Pathology ; Pneumonia* ; Pulmonary Fibrosis ; Rabbits* ; Squalene ; Tomography, X-Ray Computed ; Trachea