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The medicinal potential of promising marine organisms: A review

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Abstract

In the sea, there are many resources and novel chemical entities with biological activities that may be useful for finding drugs with greater efficacy and specificity to treat a variety of human diseases. Although there are some reports on promising natural products to date, the technology on small-molecule-based methods to isolate protein sets using a proteomic approach, which is currently useful for pharmaceuticals, is lacking. The separation of proteins from marine organisms, especially calcifying marine organisms, which are part of one of the most biologically diverse and ecologically important ecosystems on the planet, is difficult due to contamination by skeletal tissues and the high sensitivity of tissues to handling. Here, I highlight some recent studies of marine organisms, paying particular attention to their discovery, medicinal activities, and mechanisms of action. In addition, I discuss an effective protocol from sample preparation to protein purification for proteomic analysis to isolate candidate proteins for target identification, helping turn the current wealth of proteomic information into drug discovery and optimization. This information might be useful for medicinal chemists, biologists and biotechnologists for further studies utilizing the great resources of these promising marine organisms.

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... For example, some of these proteins with human physiological activity can help accelerate lab-based bone morphogenesis and increase bone volumes with efficacies equivalent to currently used recombinant proteins [1]. Proteins with potential for bone repair and drug discovery, extracted either from naturally occurring skeletal organic matrices or derived from cultivated tissues, can be identified and isolated using chromatography, cell assays and proteomic methods [1,9,11]. Proteomics is a high-throughput analytical method for rapidly identifying known or unknown proteins in complex mixtures [5]. If purification methods can be established for skeletal proteins derived from calcifying marine organisms, researchers in the emerging fields of proteomics and medicinal chemistry could utilize these methods for subsequent drug discovery and, as a more specific example, bone repair. ...
... Pharmaceutical industries now accept the world's oceans as a major frontier for medical research. The emergence of this relatively new area of scientific exploration has been of enormous interest to the popular and scientific press, and several review publications have appeared on the topic [1,9,11]. In the review presented here, we focus on recent progress in the discovery and production of new marine skeletal proteins and polysaccharides of pharmaceutical interest. ...
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Marine natural products have become a major source of new chemical entities in the discovery of potential anticancer agents that potently suppress various molecular targets. In particular, the marine macrolides, which include an array of novel biomolecules endowed with outstanding cytotoxic and/or antiproliferative activities, are a prominent class of marine natural products that offer continued promise for breakthroughs in anticancer research. Herein we highlight some recent studies of promising marine macrolides, paying particular attention to their discovery, anticancer activities, mechanisms of action, chemical synthesis, and representative analogues.
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Natural compounds obtained from marine organisms have received considerable attention as potential sources of novel drugs for treatment of human inflammatory diseases. Capnellene, isolated from the marine soft coral Capnella imbricate, 4,4,6a-trimethyl-3-methylene-decahydro-cyclopenta[]pentalene-2,3a-diol (GB9) exhibited anti-inflammatory actions on activated macrophages in vitro. Here we have assessed the anti-neuroinflammatory properties of GB9 and its acetylated derivative, acetic acid 3a-hydroxy-4,4,6a-trimethyl-3-methylene-decahydro-cyclopenta[]pentalen-2-yl ester (GB10). Effects of GB9 or GB10 on the expression of inducible nitric oxide synthase (iNOS), and cyclooxygenase-2 (COX-2) in interferon-gamma (IFN-gamma)-stimulated mouse microglial BV2 cells were measured by Western blot. The in vivo effects of these compounds were examined in the chronic constriction injury (CCI) rat model of neuropathic pain, measuring thermal hyperalgesia, and microglial activation and COX-2 protein in lumbar spinal cord, by immunohistochemistry. In BV2 cells, GB9 and GB10 inhibited the expression of iNOS and COX-2, stimulated by IFN-gamma. Intrathecal administration of GB9 and GB10 inhibited CCI-induced nociceptive sensitization and thermal hyperalgesia in a dose-dependent manner. Intraperitoneal injection of GB9 inhibited CCI-induced thermal hyperalgesia and also inhibited CCI-induced activation of microglial cells and up-regulation of COX-2 in the dorsal horn of the lumbar spinal cord ipsilateral to the injury. Taken together, these data indicate that the marine-derived capnellenes, GB9 and GB10, had anti-neuroinflammatory and anti-nociceptive properties in IFN-gamma-stimulated microglial cells and in neuropathic rats respectively. Therefore, capnellene may serve as a useful lead compound in the search for new therapeutic agents for treatment of neuroinflammatory diseases.
Article
Drugs from the sea are as much a potential marine resource as cultivated fish, and mineral deposits. The study of the chemical structure and properties of unusual metabolic products of marine life is a subject where marine ecology and the experimental sciences of chemistry, biochemistry, pharmacology and medicine share a common and complementary interest. The development of ad hoc collaboration between specialists has advanced basic knowledge and resulted in a significant feedback to marine biology and ecology as well as in the development of some useful drugs.
Article
A significant proportion of the soluble protein of the organic matrix of mollusk shells is composed of a repeating sequence of aspartic acid separated by either glycine or serine. This regularly spaced, negatively charged aspartic acid may function as a template upon which mineralization occurs.
Article
This review of phospholipase A2 (PLA2) inhibitors from marine organisms presents a compilation of research in this field over the past decade. As an introduction to the research on marine natural products, there is an overview of the role of PLA2 in inflammation that provides a rationale for seeking inhibitors of PLA2 as anti-inflammatory agents. A radiometric assay to measure inhibition of bee venom PLA2 is described in detail. Examples of marine natural products that inhibit PLA2 are manoalide and its derivatives, scalaradial and related compounds, the pseudopterosins, the vidalols, and a group of terpenoids that contain masked 1,4-dicarbonyl moieties.