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Topic Review
Cell Membrane Theory of Senescence
Lipids are an essential constituent of the cell membrane of which polyunsaturated fatty acids (PUFAs) are the most important component. Activation of phospholipase A2 (PLA2) induces the release of PUFAs from the cell membrane that form precursors to both pro- and ant-inflammatory bioactive lipids that participate in several cellular processes. PUFAs GLA (gamma-linolenic acid), DGLA (dihomo-GLA), AA (arachidonic acid), EPA (eicosapentaenoic acid) and DHA (do-cosahexaenoic acid) are derived from dietary linoleic acid (LA) and alpha-linolenic acid (ALA) by the action of desaturases whose activity declines with age. Consequently, aged cells are deficient in GLA, DGLA, AA, AA, EPA and DHA and their metabolites. LA, ALA, AA, EPA and DHA can also be obtained direct from diet and their deficiency (fatty acids) may indicate malnutrition and deficiency of several minerals, trace elements and vitamins some of which are also much needed co-factors for the normal activity of desaturases. In many instances (patients) the plasma and tissue levels of GLA, DGLA, AA, EPA and DHA are low (as seen in patients with hyperten-sion, type 2 diabetes mellitus) but they do not have deficiency of other nutrients. Hence, it is reasonable to consider that the deficiency of GLA, DGLA, AA, EPA and DHA noted in these condi-tions are due to the decreased activity of desaturases and elongases. PUFAs stimulate SIRT1 through protein kinase A-dependent activation of SIRT1-PGC1α complex and thus, increase rates of fatty acid oxidation and prevent lipid dysregulation associated with aging. 
  • 1.8K
  • 19 Mar 2021
Topic Review
Glycosylation
Post-translational modifications are one way that biomineral-associated cells control the function and fate of proteins. Of the ten different types of post-translational modifications, one of the most interesting and complex is glycosylation, or the covalent attachment of carbohydrates to amino acid sidechains Asn, Ser, and Thr of proteins. There are several biomineral-associated glycoproteins that have been characterized, and a subset of these have been the subject of intensive in vitro experimentation.  These studies indicate that glycosylation does not alter the inherent function of the biomineralization protein; rather, it either accentuates or attenuates protein functionality. In essence, glycosylation gives the cell the “last word” as to what degree a biomineralization protein will participate in the biomineralization process.
  • 1.8K
  • 25 Sep 2020
Topic Review
Secondary Metabolites Based-Plant Origin
Natural products are compounds produced by living organisms and can be divided into two main categories: primary (PMs) and secondary metabolites (SMs). Plant PMs are crucial for plant growth and reproduction since they are directly involved in living cell processes, whereas plant SMs are organic substances directly involved in plant defense and resistance. SMs are divided into three main groups: terpenoids, phenolics and nitrogen-containing compounds. The SMs contain a variety of biological capabilities that can be used as flavoring agents, food additives, plant-disease control, strengthen plant defenses against herbivores and, additionally, it can help plant cells to be better adapted to the physiological stress response. 
  • 1.8K
  • 28 Feb 2023
Topic Review
Gain of Function Mutant p53 in Cancer
The tumor suppressor p53, encoded by the TP53 gene and known as “the guardian of the genome”, performs a variety of functions in cancer prevention.
  • 1.8K
  • 17 Nov 2022
Topic Review
Curcumin in Chronic Hepatitis
Curcumin, as a natural product, is inexpensive, without side effects, and can stimulate very well certain areas of the human immune system. The cytotoxicity of curcumin as photosensitizer could be expanded by the intravenous blue laser blood irradiation (IVBLBI) or photobiomodulation in patients with chronic hepatitis B infection, Hepatitis B e-antigen (HBeAg)-positive, noncirrhotic, but nonresponsive to classical therapy. 
  • 1.7K
  • 26 May 2021
Topic Review
Tissue Inhibitor of Metalloproteases 3
The proteolytical cleavage of transmembrane proteins with subsequent release of their extracellular domain, so-called ectodomain shedding, is a post-translational modification that plays an essential role in several biological processes, such as cell communication, adhesion and migration. Metalloproteases are major proteases in ectodomain shedding, especially the disintegrin metalloproteases (ADAMs) and the membrane-type matrix metalloproteases (MT-MMPs), which are considered to be canonical sheddases for their membrane-anchored topology and for the large number of proteins that they can release. The unique ability of tissue inhibitor of metalloproteases 3 (TIMP-3) to inhibit different families of metalloproteases, including the canonical sheddases (ADAMs and MT-MMPs), renders it a master regulator of ectodomain shedding. 
  • 1.7K
  • 16 Mar 2022
Topic Review
Protein-Based Targeting Self-Assembling Nanoparticles for Biomedical Applications
Targeted nanoparticles of different origins are considered as new-generation diagnostic and therapeutic tools. Targeted protein self-assembling nanoparticles circumvent this problem since proteins are encoded in DNA and the final protein product is produced in only one possible way. The combination of the endless biomedical potential of protein carriers as nanoparticles and the standardized protein purification protocols will make significant progress in “magic bullet” creation possible, bringing modern biomedicine to a new level. The entry focused on the currently existing platforms for targeted self-assembling protein nanoparticles based on transferrin, lactoferrin, casein, lumazine synthase, albumin, ferritin, and encapsulin proteins, as well as on proteins from magnetosomes and virus-like particles. The applications of these self-assembling proteins for targeted delivery in vitro and in vivo are thoroughly discussed, including bioimaging applications and different therapeutic approaches, such as chemotherapy, gene delivery, and photodynamic and photothermal therapy. 
  • 1.7K
  • 08 Mar 2023
Topic Review
Toll-Like Receptor 4
Toll-like receptors (TLRs) are type I transmembrane glycoproteins belonging to the complex pattern recognition receptors (PRRs) expressed in immune and non-immune cells, including neurons and glia, which are involved in the regulation of innate immune and inflammatory responses. The TLR family comprises 11 members (TLR1–TLR11) in human and 12 (TLR1–TLR9, TLR11–TLR13) in mouse. TLR4 is one of the best characterized TLRs that surveys for the presence of structural motifs in a wide array of invading microorganisms, named pathogen-associated molecular patterns (PAMPs), and endogenous damage or danger molecular patterns (DAMPs), also known as alarmins, released by damaged cells and injured tissues or derived from apoptotic and necrotic cells. Activation of TLR4 induces the downstream start of inflammasome pathways which results in the release of a plethora of pro-inflammatory cytokines, Type I interferons (IFNs) and other inflammatory mediators.
  • 1.7K
  • 28 Mar 2023
Topic Review
Overview of Cdc25 Phosphatases
The cell division cycle 25 (Cdc25) phosphatases are dual-specificity phosphatases (DSPs) that catalyze the dephosphorylation of the Cdk/Cyc protein complex, an important regulator of the human cell cycle. In human cells, three Cdc25 phosphatases are characterized, Cdc25A, Cdc25B, and Cdc25C, which share the similarity of amino acids identity from 20 to 25% for N-terminal and 60% similarity for C-terminal, and are differentially expressed in the cell division cycle. Cdc25 phosphatases have been considered promising targets for anticancer development due to the correlation of their overexpression with a wide variety of cancers. In the past decades, the interest in this subject has considerably increased and many publications have been launched concerning this issue.
  • 1.7K
  • 21 Apr 2022
Topic Review
Lipid Phosphate Phosphatases
Lipid phosphate phosphatases (LPPs) consist of three enzymes (LPP1–3), which have been classified as phospholipid phosphatases (PLPP). The LPPs dephosphorylate a wide spectrum of bioactive lipid phosphates, among which lysophosphatidate (LPA) and sphingosine 1-phosphate (S1P) are two important extracellular signaling molecules. The LPPs are integral membrane proteins, which are partly localized on plasma membranes. These activities participate in regulating the concentrations of extracellular LPA and S1P and thus signaling through their families of G protein coupled receptors. The expression of the LPPs on intracellular membranes, including endoplasmic reticulum and Golgi net work, are thought to attenuate signaling downstream of the activation of LPA and protease activates receptors. The LPPs differentially regulate signal transduction in cancer cells. LPP1 and LPP3 have decreased expressions in several caners and this is associated with increased tumor growth and metastasis.  Conversely, LPP2 activity is increased in these cancers and this accelerates progression through the cell cycle. Increasing the relative activities of LPP1 and LPP3 and decreasing LPP2 activity, therefore, provides a novel approach to treating some cancers.
  • 1.7K
  • 11 Sep 2020
Topic Review
Histone Acetyltransferase GCN5
Transcription of protein-encoding genes starts with forming a pre-initiation complex comprised of RNA polymerase II and several general transcription factors. To activate gene expression, transcription factors must overcome the repressive chromatin structure, which is accomplished with multiprotein complexes. Histone Acetyl Transferases (HAT) catalyze acetylation of specific lysine residues in histone N-tails, which are involved in transcriptional regulation and other nuclear processes. HATs are parts of large multiprotein complexes, like the SAGA complex, where their activity is enhanced, and their substrate specificity is altered. The whole complex is recruited to target sequences on the genome with other components involved in protein-protein interactions. A prototypical HAT which acts as a transcriptional adaptor is known as General Control Nonrepressed protein 5 (GCN5), first identified in Saccharomyces cerevisiae. GCN5 was defined biochemically as the first transcription-linked HAT with specificity for histone H3 lysine 14 (H3K14). However, GCN5 could also acetylate additional histone lysine residues, such as H3K9, H3K18, H3K23, H3K27, H3K36, other histones such as H4 and H2B and non-histone nuclear proteins.  In Arabidopsis, GCN5 is required for many developmental processes such as leaf development, apical dominance, root meristem activity, inflorescence, floral meristem function and flower fertility. 
  • 1.7K
  • 10 Feb 2021
Topic Review
Reactive Oxygen Species in Malaria Treatment
Malaria is a vector-transmitted parasite disease that continues to plague mankind. It is caused in humans by five main species of Plasmodium. The majority of conventional antimalarials kill parasites via direct or indirect overproduction of reactive oxygen species (ROS). Even when some parasites try to manage these ROS, over production of the ROS still leads to parasite death. This therefore underscores the role of ROS in the antiplasmodial activity of different antimalarials.
  • 1.7K
  • 04 Mar 2022
Topic Review
Calprotectin As a Drug Target
Calprotectin (CP), a heterodimer of S100A8 and S100A9 EF-hand calcium-binding proteins, is an integral part of the innate immune response. CP exploits the metal requirement of pathogens in the host immune response through the chelation of transition metals, starving pathogens of these nutrients. In addition, CP plays a role in the inflammatory response by acting as a ligand for cell surface receptors that signal through the NF-κB signaling pathway.
  • 1.7K
  • 21 Apr 2022
Topic Review
Endoplasmic Reticulum's Applications in Mitochondrial Proteins
Most mitochondrial proteins are synthesized in the cytosol and targeted to the mitochondrial surface in a post-translational manner. The surface of the endoplasmic reticulum (ER) plays an active role in this targeting reaction. ER-associated chaperones interact with certain mitochondrial membrane protein precursors and transfer them onto receptor proteins of the mitochondrial surface in a process termed ER-SURF.
  • 1.7K
  • 26 Oct 2021
Topic Review
Digital Droplet PCR in Hematologic Malignancies
Digital Droplet Polymerase Chain Reaction (ddPCR) is a specific, accurate and time-saving technique capables of accurately quantifying gene expression or detecting point mutations applicable in several hematologic disorders, such as leukemias, lymphomas, myeloma, and chronic myeloproliferative neoplasms, and in transplant field. The ddPCR might provide useful informations in prognostic and therapeutic setting.
  • 1.7K
  • 24 Jun 2022
Topic Review
Impact of Polyphenolic-Food on Longevity
Aging and, particularly, the onset of age-related diseases are associated with tissue dysfunction and macromolecular damage, some of which can be attributed to accumulation of oxidative damage. Recently, growing interest has emerged on the beneficial effects of plant-based diets for the prevention of chronic diseases including obesity, diabetes, and cardiovascular disease. Several studies collectively suggests that the intake of polyphenols and their major food sources may exert beneficial effects on improving insulin resistance and related diabetes risk factors, such as inflammation and oxidative stress. They are the most abundant antioxidants in the diet, and their intake has been associated with a reduced aging in humans. Polyphenolic intake has been shown to be effective at ameliorating several age-related phenotypes, including oxidative stress, inflammation, impaired proteostasis, and cellular senescence, both in vitro and in vivo.
  • 1.7K
  • 04 May 2021
Topic Review
The Role of Flavonoids in Plant Terrestrialization
Plants evolved an impressive arsenal of specialized metabolites to cope with the novel environmental pressures imposed by the terrestrial habitat when moving from water. Flavonoids are maybe the most important specilized metabolites that show multifarious roles in the sucess of plant terrestrialization. These compounds modulated auxin transport and signaling and promoted the symbiosis between plants and fungi (e.g., arbuscular mycorrhizal, AM), a central event for the conquest of land by plants. AM improved the ability of early plants to take up nutrients and water from highly impoverished soils. Therefore, flavonoids were essential to plant development in the “new world” scarce of water and nutrients.
  • 1.7K
  • 30 May 2022
Topic Review
Therapeutic Potential of G-quadruplex Structural Junctions
We analyze further extension of G-quadruplexes by additional structural elements and investigate whether junction of G-quadruplex with duplex, hairpin, triplex or second G-quadruplex motif is favorable for aptamers stability and biological activity. Furthermore, we indicate the specific and pivotal role of G-quadruplex domain and the additional structural elements in the interactions with target molecules. Finally, we consider the potency of G-quadruplex junctions in the future applications and indicate the emerging research area that is still waiting for development to obtain highly specific and effective nucleic acid-based molecular tools.
  • 1.7K
  • 15 Oct 2021
Topic Review
Nutritional Profile of Chilli
Chilli pepper, botanically Capsicum annuum L., is an indispensable vegetable cum spice crop grown commercially worldwide for its immature green and red ripe fruits. Universally, the crop is consumed and appreciated for its flavor, colour, aroma, texture, and preserving foods. The crop was probably first used among folks as medicinal plants for its rich bountiful and diversified nutrients, even before it was used in cooking. The understanding on use of such plants helped the masses to sustain since ancient times.
  • 1.7K
  • 17 Oct 2022
Topic Review
Recent Applications of Retro-Inverso Peptides
Retro-inverso peptides possess reversed sequences and chirality compared to the parent molecules maintaining at the same time an identical array of side chains and in some cases similar structure. The inverted chirality renders them less prone to degradation by endogenous proteases conferring enhanced half-lives and an increased potential as new drugs. However, given their general incapability to adopt the 3D structure of the parent peptides their application should be careful evaluated and investigated case by case.
  • 1.7K
  • 22 Sep 2021
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