Natural Polysaccharides with Immunomodulatory Activities

2020 ◽  
Vol 20 (2) ◽  
pp. 96-106
Author(s):  
Yue Zhao ◽  
Bocheng Yan ◽  
Zhaoyu Wang ◽  
Mingjing Li ◽  
Wei Zhao
Keyword(s):  
Biological Activities ◽  
Structural Characteristics ◽  
Structural Features ◽  
Therapeutic Action ◽  
Immunostimulatory Activity ◽  
Natural Polysaccharide ◽  
Different Origins

Natural polysaccharide is a kind of natural macromolecular which can be extracted from plants, fungi, algae, animals, and bacteria. The monosaccharide compositions and glucosidic bonds of polysaccharides from different origins vary substantially. Natural polysaccharides have been shown to possess complex, important and multifaceted biological activities including antitumor, anticoagulant, antioxidative, antiviral, immunomodulatory, antihyperlipidemic and antihepatotoxic activities. Their properties are mainly due to their structural characteristics. It is necessary to develop polysaccharide immunomodulators with potential for preventive or therapeutic action. The present paper summarizes the structural features, immunostimulatory activity and the immunomodulatory mechanisms of natural polysaccharides. In particular, it also provides an overview of representative natural polysaccharide immunomodulators.

Hybrids of Coumarin Derivatives as Potent and Multifunctional Bioactive Agents: A Review

2020 ◽  
Vol 16 (3) ◽  
pp. 272-306
Author(s):  
Ioannis Fotopoulos ◽  
Dimitra Hadjipavlou-Litina
Keyword(s):  
Pharmacological Activity ◽  
Biological Activities ◽  
Structural Characteristics ◽  
Pharmacokinetic Profile ◽  
Biologically Active ◽  
Hybridization Technique ◽  
Coumarin Derivatives ◽  
Hybrid Molecules ◽  
Pharmacokinetic Properties ◽  
Bioactive Agents

Background: Coumarins exhibit a plethora of biological activities, e.g. antiinflammatory and anti-tumor. Molecular hybridization technique has been implemented in the design of novel coumarin hybrids with several bioactive groups in order to obtain molecules with better pharmacological activity and improved pharmacokinetic profile. Objective: Therefore, we tried to gather as many as possible biologically active coumarin hybrids referred in the literature till now, to delineate the structural characteristics in relation to the activities and to have a survey that might help the medicinal chemists to design new coumarin hybrids with drug-likeness and varied bioactivities. Results: The biological activities of the hybrids in most of the cases were found to be different from the biological activities presented by the parent coumarins. The results showed that the hybrid molecules are more potent compared to the standard drugs used in the evaluation experiments. Conclusion: Conjugation of coumarin with varied pharmacophore groups/druglike molecules responsible for different biological activities led to many novel hybrid molecules, with a multitarget behavior and improved pharmacokinetic properties.

scholarly journals Sphingolipids of Asteroidea and Holothuroidea: Structures and Biological Activities

Marine Drugs ◽  
2021 ◽  
Vol 19 (6) ◽  
pp. 330
Author(s):  
Timofey V. Malyarenko ◽  
Alla A. Kicha ◽  
Valentin A. Stonik ◽  
Natalia V. Ivanchina
Keyword(s):  
Marine Invertebrates ◽  
Biological Activities ◽  
Complete Information ◽  
Structural Features ◽  
Marine Organisms ◽  
Structural Components ◽  
Chemical Structures ◽  
The Past ◽  
Complex Lipids ◽  
Complex Sphingolipids

Sphingolipids are complex lipids widespread in nature as structural components of biomembranes. Commonly, the sphingolipids of marine organisms differ from those of terrestrial animals and plants. The gangliosides are the most complex sphingolipids characteristic of vertebrates that have been found in only the Echinodermata (echinoderms) phylum of invertebrates. Sphingolipids of the representatives of the Asteroidea and Holothuroidea classes are the most studied among all echinoderms. In this review, we have summarized the data on sphingolipids of these two classes of marine invertebrates over the past two decades. Recently established structures, properties, and peculiarities of biogenesis of ceramides, cerebrosides, and gangliosides from starfishes and holothurians are discussed. The purpose of this review is to provide the most complete information on the chemical structures, structural features, and biological activities of sphingolipids of the Asteroidea and Holothuroidea classes.

scholarly journals Recent Developments in Inonotus obliquus (Chaga mushroom) Polysaccharides: Isolation, Structural Characteristics, Biological Activities and Application

Polymers ◽  
2021 ◽  
Vol 13 (9) ◽  
pp. 1441
Author(s):  
Yangpeng Lu ◽  
Yanan Jia ◽  
Zihan Xue ◽  
Nannan Li ◽  
Junyu Liu ◽  
...  
Keyword(s):  
Biological Activities ◽  
Structural Characteristics ◽  
Potential Candidate ◽  
Health Food ◽  
Inonotus Obliquus ◽  
Recent Developments ◽  
Inonotus Obliquus Polysaccharide ◽  
Future Work

Inonotus obliquus (Chaga mushroom) is a kind of medicine and health food widely used by folk in China, Russia, Korea, and some occidental countries. Among the extracts from Inonotus obliquus, Inonotus obliquus polysaccharide (IOPS) is supposed to be one of the major bioactive components in Inonotus obliquus, which possesses antitumor, antioxidant, anti-virus, hypoglycemic, and hypolipidemic activities. In this review, the current advancements on extraction, purification, structural characteristics, and biological activities of IOPS were summarized. This review can provide significant insight into the IOPS bioactivities as their in vitro and in vivo data were summarized, and some possible mechanisms were listed. Furthermore, applications of IOPS were reviewed and discussed; IOPS might be a potential candidate for the treatment of cancers and type 2 diabetes. Besides, new perspectives for the future work of IOPS were also proposed.

Structural features and functional domains of amassin-1, a cell-binding olfactomedin protein

2007 ◽  
Vol 85 (5) ◽  
pp. 552-562 ◽  
Author(s):  
Brian J. Hillier ◽  
Victor D. Vacquier
Keyword(s):  
Disulfide Bonds ◽  
Biological Activities ◽  
Structural Features ◽  
Body Cavity ◽  
Binding Activity ◽  
Coiled Coils ◽  
Cell Binding ◽  
Calcium Dependent ◽  
Dependent Cell ◽  
A Cell

Amassin-1 mediates a rapid cell adhesion that tightly adheres sea urchin coelomocytes (body cavity immunocytes) together. Three major structural regions exist in amassin-1: a short β region, 3 coiled coils, and an olfactomedin domain. Amassin-1 contains 8 disulfide-bonded cysteines that, upon reduction, render it inactive. Truncated forms of recombinant amassin-1 were expressed and purified from Pichia pastoris and their disulfide bonding and biological activities investigated. Expressed alone, the olfactomedin domain contained 2 intramolecular disulfide bonds, existed in a monomeric state, and inhibited amassin-1-mediated clotting of coelomocytes by a calcium-dependent cell-binding activity. The N-terminal β region, containing 3 cysteines, was not required for clotting activity. The coiled coils may dimerize amassin-1 in a parallel orientation through a homodimerizing disulfide bond. Neither amassin-1 fragments that were disulfide-linked as dimers or that were engineered to exist as dimers induced coelomocytes clotting. Clotting required higher multimeric states of amassin-1, possibly tetramers, which occurred through the N-terminal β region and (or) the first segment of coiled coils.

Tanshinone IIA: Pharmacology, total synthesis, and progress in structure-modifications

2021 ◽  
Vol 28 ◽  
Author(s):  
Xing Huang ◽  
Hao Deng ◽  
Qing-kun Shen ◽  
Zhe-Shan Quan
Keyword(s):  
Herbal Medicine ◽  
Total Synthesis ◽  
Chinese Herbal Medicine ◽  
Biological Activities ◽  
Structural Features ◽  
Tanshinone Iia ◽  
Structural Modifications ◽  
Chinese Herbal ◽  
Bioactive Constituent

: Tanshinone IIA, a major bioactive constituent of Danshen, a Chinese herbal medicine, has gained extensive exploration owing to its unique structural features and multiple promising biological activities. This review focuses on the pharmacology, total synthesis, and structural modifications of tanshinone IIA. We hope this review will contribute to a better understanding of the progress in the field and provide constructive suggestions for further study of tanshinone IIA.

scholarly journals The Natural Compound Hydrophobic Usnic Acid and Hydrophilic Potassium Usnate Derivative: Applications and Comparisons

Molecules ◽  
2021 ◽  
Vol 26 (19) ◽  
pp. 5995
Author(s):  
Hallysson Douglas Andrade de Araújo ◽  
Hianna Arely Milca Fagundes Silva ◽  
José Guedes da Silva Júnior ◽  
Mônica Camelo Pessoa de Azevedo Albuquerque ◽  
Luana Cassandra Breitenbach Barroso Coelho ◽  
...  
Keyword(s):  
Biological Activities ◽  
Structural Characteristics ◽  
Usnic Acid ◽  
Raw Material ◽  
Structural Modifications ◽  
Hydrophobic Molecule ◽  
Antiparasitic Agents ◽  
Toxic Molecule

Usnic acid is the best-studied lichen metabolite, presenting several biological activities, such as antibacterial, immunostimulating, antiviral, antifungal, anti-inflammatory, and antiparasitic agents; despite these relevant properties, it is a hydrophobic and toxic molecule. In this context, scientific research has driven the development of innovative alternatives, considering usnic acid as a source of raw material in obtaining new molecules, allowing structural modifications (syntheses) from it. The purpose is to optimize biological activities and toxicity, with less concentration and/or response time. This work presents a literature review with an analogy of the hydrophobic molecule of usnic acid with its hydrophilic derivative of potassium usnate, emphasizing the elucidation and structural characteristics, biological activities, and toxicological aspects of both molecules, and the advantages of using the promising derivative hydrophilic in different in vitro and in vivo assays when compared to usnic acid.

Wingless signaling generates pattern through two distinct mechanisms

Development ◽  
1997 ◽  
Vol 124 (19) ◽  
pp. 3727-3736 ◽  
Author(s):  
R. Hays ◽  
G.B. Gibori ◽  
A. Bejsovec
Keyword(s):  
Cell Fate ◽  
Cellular Response ◽  
Biological Activities ◽  
Essential Feature ◽  
Structural Features ◽  
Protein Distribution ◽  
Wild Type ◽  
Cell Fates ◽  
Amino Acid Region ◽  
Acid Region

wingless (wg) and its vertebrate homologues, the Wnt genes, play critical roles in the generation of embryonic pattern. In the developing Drosophila epidermis, wg is expressed in a single row of cells in each segment, but it influences cell identities in all rows of epidermal cells in the 10- to 12-cell-wide segment. Wg signaling promotes specification of two distinct aspects of the wild-type intrasegmental pattern: the diversity of denticle types present in the anterior denticle belt and the smooth or naked cuticle constituting the posterior surface of the segment. We have manipulated the expression of wild-type and mutant wg transgenes to explore the mechanism by which a single secreted signaling molecule can promote these distinctly different cell fates. We present evidence consistent with the idea that naked cuticle cell fate is specified by a cellular pathway distinct from the denticle diversity-generating pathway. Since these pathways are differentially activated by mutant Wg ligands, we propose that at least two discrete classes of receptor for Wg may exist, each transducing a different cellular response. We also find that broad Wg protein distribution across many cell diameters is required for the generation of denticle diversity, suggesting that intercellular transport of the Wg protein is an essential feature of pattern formation within the epidermal epithelium. Finally, we demonstrate that an 85 amino acid region not conserved in vertebrate Wnts is dispensable for Wg function and we discuss structural features of the Wingless protein required for its distinct biological activities.

scholarly journals Three Structural Features of Functional Food Components and Herbal Medicine with Amyloid β42 Anti-Aggregation Properties

Molecules ◽  
2019 ◽  
Vol 24 (11) ◽  
pp. 2125 ◽  
Author(s):  
Kazuma Murakami ◽  
Kazuhiro Irie
Keyword(s):  
Amino Acid ◽  
Functional Food ◽  
Structural Characteristics ◽  
Salt Bridge ◽  
Basic Amino Acid ◽  
Structural Features ◽  
Amino Acid Residues ◽  
Treatment And Prevention ◽  
Food Components ◽  
Underlying Mechanisms

Aggregation of amyloid β42 (Aβ42) is one of the hallmarks of Alzheimer’s disease (AD). There are numerous naturally occurring products that suppress the aggregation of Aβ42, but the underlying mechanisms remain to be elucidated. Based on NMR and MS spectroscopic analysis, we propose three structural characteristics found in natural products required for the suppressive activity against Aβ42 aggregation (i.e., oligomerization by targeting specific amino acid residues on this protein). These characteristics include (1) catechol-type flavonoids that can form Michael adducts with the side chains of Lys16 and 28 in monomeric Aβ42 through flavonoid autoxidation; (2) non-catechol-type flavonoids with planarity due to α,β-unsaturated carbonyl groups that can interact with the intermolecular β-sheet region in Aβ42 aggregates, especially aromatic rings such as those of Phe19 and 20; and (3) carboxy acid derivatives with triterpenoid or anthraquinoid that can generate a salt bridge with basic amino acid residues such as Lys16 and 28 in the Aβ42 dimer or trimer. Here, we summarize the recent body of knowledge concerning amyloidogenic inhibitors, particularly in functional food components and Kampo medicine, and discuss their application in the treatment and prevention of AD.

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