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A mini-review of literature data on the mechanisms of formation of the stock of free amino acids and their derivatives in liver pathology and methods for correcting metabolic imbalance
Cancer is the leading cause of death worldwide, and there is a constant need for new treatment strategies. Sesquiterpene lactones containing a 3-methylenedihydrofuran-2(3H)-one (or α-methylene-γ-lactone) moiety, for example damsin (1), are Michael acceptors that affect biological processes such as cell proliferation, death/apoptosis, and cell migration, by interfering with cell signalling pathways. Although the reactivity of the α-methylene-γ-lactone moiety is important for these effects, the Michael addition is reversible and it can be assumed that also other parts of the molecules will moderate any given biological activity. In this investigation, the cytotoxicity of 23 -methylene--lactones towards normal breast epithelial MCF-10A cells as well as breast cancer JIMT-1 cells is compared. Most of the investigated compounds are semisynthetic derivatives prepared by the condensation of the natural product damsin (1) with aldehydes. The two cell lines were treated with various concentrations of the compounds in dose response assays, and the 50 % inhibitory concentration (IC50) was determined from dose response curves. The IC50 values were found to depend strongly on the overall structure. The ratio between the IC50 values for MCF-10A and JIMT-1 cells, as a measure for the selectivity of a compound to kill cancer cells, was calculated, and found to vary between just over 1 to more than 10. The most potent derivatives formed from the condensation of 1 with aromatic aldehydes towards JIMT-1 cells are 3a and 3i, both with ratios between the IC50 values for MCF-10A and JIMT-1 cells close to 5. Also some aldol condensation products with acyclic aldehydes, i.e. 3r and 3u, were equally potent, and the latter showed the highest selectivity (ratio > 10). Structure-activity relationships that may explain the observed differences in potency and selectivity are discussed.
Disposal of chitin wastes from crustacean shell can cause environmental and health hazards. Chitin is a well known abundant natural polymer extracted after deproteinization and demineralization of the shell wastes of shrimp, crab, lobster, and krill. Extraction of chitin and its derivatives from waste material is one of the alternative ways to turn the waste into useful products. Chitinases are enzymes that degrade chitin. Chitinases contribute to the generation of carbon and nitrogen in the ecosystem. Chitin and chitinolytic enzymes are gaining importance for their biotechnological applications. The presence of surface charge and multiple functional groups make chitin as a beneficial natural polymer. Due to the reactive functional groups chitin can be used for the preparation of a spectrum of chitin derivatives such as chitosan, alkyl chitin, sulfated chitin, dibutyryl chitin and carboxymethyl chitin for specific applications in different areas. The present review is aimed to summarize the efficacy of the chitinases on the chitin and its derivatives and their diverse applications in biomedical and environmental field. Further this review also discusses the synthesis of various chitin derivatives in detail and brings out the importance of chitin and its derivatives in biomedical and environmental applications.
A stereoselective synthesis of N-glycosyl amides was studied from available N-glycosyl oxazolines prepared by Ritter-like reactions of protected sugar acetonides. Hydrolysis reactions of the protected pentofuranosyl and hexafuranosyl oxazolines, as precursors of glycosyl amine derivatives, were carried out in the presence of silica gel in chloroform to giveN-α- and β-glycosyl amides in good yields after column chromatography on silica gel. Access to selectively blocked N-α-xylo-, -ribo-, β-arabino-furanosyl, α-glyco-, α-allo-furanosyl, α- and β-galactopyranosyl amides (twelve examples) useful for preparing modified N-glycosides was accomplished through a mild hydrolysis of sugar oxazolines with 2-alkyl substituents in acidic and neutral conditions. To further explore the scope of the BF3.Et2O-mediated approachdeveloped for N-furanosyl oxazolines, a stereoselective synthesis of protected N-α-hexopyranosyl oxazoline was fulfilled in a high yield from d-galactopyranose diacetonide derivative. The Ritter-like promoted reaction between D-arabinose and benzonitrile afforded 2-phenyl-β-d-arabinofurano-(1,2-d)-2-oxazoline as the main product. In acetonitrile the BF3.Et2O-KHF2-assisted reactions of unprotected native sugars were found to result in the formation of mixtures of N-furanosyl and pyranosyl acetamides.
A stereoselective synthesis of protected N-glycosyl oxazolines has been developed from available acylated sugar 1,2-O-acetonides using intramolecular Ritter-like reactions. New N-α- and β-D-pentofuranosyl, α-D-hexofuranosyl oxazolines as valuable intermediates for preparation of diverse N-glycosides were obtained by BF3.OEt2-KHF2 or BF3.OEt2-promoted reactions of pentofuranose and hexafuranose acetonide derivatives with nitriles. When selectively acylated D-xylo- or ribofuranoses were employed in the reactions, N-α-pentofuranosyl oxazolines were prepared in good yields. A mechanism for the formation of glycosyl oxazolines was proposed. A series of oxazoline derivatives were evaluated for their antiproliferative activity on three human cancer cell lines (MCF-7, Hela and K562).
Hox genes, their conserved derivatives, and the pathways responsible for their expression have been extensively studied in the fruit fly, Drosophila melanogaster;the experimentation done in the Drosophila model system has given developmental biologists tools to better understand the role and significance of Hox genes and their derivatives in anterior-posterior axis determination in the Drosophila embryo. Along with this, Drosophila research opened up the door to investigation on the conservation of Hox genes between vertebrates and invertebrates. Comparative embryology in mice, chickens, pufferfish, and zebrafish have shown conserved Hox gene expression patterns specifically along the anterior-posterior axis. Recently, comparative analysis performed on dorsal-ventral axis formation showed that patterning and segmentation of the spinal cord is influenced by the action of Hox genes as well. This review will briefly consider the evolution of the vertebrate brain and the evolution and conservation of Hox genes in regulating hindbrain patterning and spinal cord development.
Two analgesic were determined opium (morphine) and tramadol and comparison between two methods of extractions from biological samples. Opium and its derivatives and tramadol are the most commonly used medications for treatment of acute and chronic pain. opium was used as a sedative and hypnotic, but it was determined to be addictive and tramadol prescribed narcotic analgesic; main metabolite of opium is morphine and tramadol overdose was reported old male 40 years. Morphine and tramadol isolated by two methods of extraction, Stas Otto and ammonium sulfate extraction from liver tissues and comparison between efficiency of the two methods. Liver extractions have morphine and tramadol was quantified by GC-MS. Morphine was determined in liver concentration 176 u/g in Stas Otto. Liver concentration of morphine 267 u/g in ammonium sulfate extraction. Tramadol was determined in liver concentration 26.18 u/g in Stas Otto. Liver concentration of tramadol 22.41 u/g in ammonium sulfate extraction.
This article has been retracted on 18 March 2021. VIEW THE RETRACTION NOTICE (https://doi.org/10.14302/issn.2379-7835.ijn-25-5865) A mini-review of literature data on the mechanisms of formation of the stock of free amino acids and their derivatives in atherosclerosis and methods for correcting metabolic imbalance.
Membrane dynamics in the presynaptic region of the neuron is a key process of neuronal signal transduction. Dynamin plays a central part during endocytosis participating in the deformation of membrane structure and constriction. During the study of molecular interaction of presynaptic proteins, we found that dynamin fraction prepared from brain extract contains several lipid components. Fractionation of lipids with thin layer chromatography and mass-analysis showed the presence of phosphatidylcholine, phosphatidylethanolamine, cerebroside, cholesterol and its-derivatives, and triacylglycerol. Since the GTPase activity of bacterially expressed dynamin was activated by the extracted lipid fraction, lipid components that affect the GTPase activity of dynamin was screened and cerebroside, hydroxycholesterols, cholesterol, and triacylglycerol were found to activate the GTPase activity. This result not only suggests the possibility that several neutral lipids participate in the membrane dynamics, but also revealed the possibility that a protein fraction contains lipid components even if its purity was confirmed with SDS-PAGE.
Isatin (1H-indole-2,3-dione ) and derivatives demonstrate a diverse array of biological activities. Isatin and 5-halo derivatives has reacted to form the schiff’s bases , mannich bases and friedal craft alkylation’s to form C-C, C-N, C=N bonds. From the spectral studies, isatin has undergoes reaction at C-3 and N-1 position and synthesized lead in present schme and seen the similarity of structure and analgesic-anti-inflammatory activity.
Sulfonamide group is a magic group introduced as the main core for different bio-activities in drug industry. According to its substitutes, literature divides sulfonamide derivatives to antibacterial sulfonamides and non-anti-bacterial sulfonamides. As Data was collected from different sources such as Drug Bank.com and Pubchem.com databases and then was analyzed, we found that these compounds are different in their pharmacokinetics and pharmacodynamics; in addition to their sulfa cross allergy property. We presented these differences from these compounds changes in their chemical structure, in a way to build a solid base that can be depended on for developing new drugs from these compounds that interact with different receptors.
The increased association between depression and diabetes mellitus is generally acknowledged. Recent studies suggest that depression leads to diabetes.However, the underlying molecular mechanisms for this association remain unclear.Literature and our data indicate that inflammatory and/or stress factors in depression up-regulate tryptophan (TRP) conversion into kynurenine (KYN), a substrate for nicotinamide adenine dinucleotide (NAD) biosynthesis. Deficiency of vitamin B6, a co-factor of the key enzymes of KYN – NAD pathway, shunts KYN metabolism from formation of NAD towards production of xanthurenic (XA) and kynurenic (KYNA) acids. Human and experimental studies reveal that XA, KYNA and their metabolites interfere with production, release and biological activity of insulin. We propose that inflammation- and/or stress-induced up-regulation of TRP – KYN metabolism in combination with vitamin B6 deficiency is one of the mechanisms mediating increased risk of diabetes in depression. Consequently, monitoring formation of diabetogenic KYN derivatives might help to identify subjects-at-risk for the development of diabetes. Pharmacological down-regulation of the TRP – KYN – NAD pathway and maintenance of adequate vitamin B6 status might help to prevent the development of diabetes in depression and other conditions associated with inflammation/stress–induced excessive production of KYN and vitamin B6 deficiency, e.g., obesity, cardiovascular diseases, aging, menopause, pregnancy, and hepatitis C virus infection.