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Topic Review
Bisphenol A-Induced Male Infertility
Bisphenol A (BPA) is a well-known endocrine disruptor present in epoxy resins and polycarbonate plastics, which negatively disturbs the male reproductive system affecting male fertility. In vivo studies showed that BPA exposure has deleterious effects on spermatogenesis by disturbing the hypothalamic-pituitary-gonadal axis and inducing oxidative stress in the testis. This compound seems to disrupt hormone signalling even at low concentrations, modifying the levels of inhibin B, oestradiol, and testosterone. The adverse effects on seminal parameters are mainly supported by studies based on urinary BPA concentration, showing a negative association between BPA levels and sperm concentration, motility, normal morphology and sperm DNA damage.
  • 1.9K
  • 01 Apr 2021
Topic Review
The Mitochondrial Genome
Mitochondria are powerhouses of the cell and implement oxidative phosphorylation processes. Similar to plastids, mitochondria are endosymbionts of a pro-eukaryotic cell, have their own genome, and their own transcriptional and translational machinery.
  • 1.9K
  • 12 Jan 2023
Topic Review
Vascular Endothelial Glycocalyx
Vascular endothelial cells are a monolayer of cells that comprise the innermost layer of cells in the vascular system, including arteries, veins, and capillaries, and serve a barrier function for the blood vessels surrounding all organs and in direct contact with the blood flowing through the vascular lumen.
  • 1.9K
  • 30 Dec 2020
Topic Review
Beta2-Microglobulin
Beta2-microglobulin (B2M) is a key component of major histocompatibility complex class I molecules, which aid cytotoxic T-lymphocyte (CTL) immune response. B2M also plays an important role in innate defense and does not only function as an adjuvant for CTL response. 
  • 1.9K
  • 26 Jul 2021
Topic Review
ATF5 Function in Regulating Cell Stress and Survival
Activating transcription factor 5 (ATF5) belongs to the activating transcription factor/cyclic adenosine monophosphate (cAMP) response element-binding protein family of basic region leucine zipper transcription factors. ATF5 plays an important role in cell stress regulation and is involved in cell differentiation and survival, as well as centrosome maintenance and development. 
  • 1.9K
  • 27 Jul 2022
Topic Review
Homocysteine and Mitochondria
Elevated concentration of homocysteine (Hcy) in the blood plasma, hyperhomocysteinemia (HHcy), has been implicated in various disorders, including cardiovascular and neurodegenerative diseases. Accumulating evidence indicates that pathophysiology of these diseases is linked with mitochondrial dysfunction. Mitochondria are essential for maintaining cellular homeostasis and function. The interaction between Hcy and mitochondria is complex and reactive oxygen species (ROS) seem to be important mediators of Hcy effects. Although oxidative damage to mitochondria is frequently demonstrated under HHcy, Hcy may have also beneficial effects on mitochondrial function and cell viability.
  • 1.9K
  • 11 Nov 2020
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.
  • 1.9K
  • 22 Sep 2021
Topic Review
Replication Protein A
Replication protein A (RPA) is a heterotrimeric protein complex and the main single-stranded DNA (ssDNA)-binding protein in eukaryotes. RPA has key functions in most of the DNA-associated metabolic pathways and DNA damage signalling. Its high affinity for ssDNA helps to stabilise ssDNA structures and protect the DNA sequence from nuclease attacks. RPA consists of multiple DNA-binding domains which are oligonucleotide/oligosaccharide-binding (OB)-folds that are responsible for DNA binding and interactions with proteins. These RPA–ssDNA and RPA–protein interactions are crucial for DNA replication, DNA repair, DNA damage signalling, and the conservation of the genetic information of cells. Proteins such as ATR use RPA to locate to regions of DNA damage for DNA damage signalling.
  • 1.8K
  • 18 Feb 2024
Topic Review
Endoglin
Endoglin is a class I, single-membrane spanning receptor with an apparent molecular weight of 95 kDa containing a short cytoplasmic and a modular extracellular domain. This domain contains attachment sites for N- and O-dependent glycosylation and ligand binding residues.
  • 1.8K
  • 16 Apr 2021
Topic Review
Fyn
Fyn is a non-receptor or cytoplasmatic tyrosine kinase (TK) belonging to the Src family kinases (SFKs) involved in multiple transduction pathways in the central nervous system (CNS) including synaptic transmission, myelination, axon guidance, and oligodendrocyte formation. Almost one hundred years after the original description of Fyn, this protein continues to attract extreme interest because of its multiplicity of actions in the molecular signaling pathways underlying neurodevelopmental as well as neuropathologic events. Fyn is a common factor in healthy and diseased brains that targets different proteins and shapes different transduction signals according to the neurological conditions. In particular, Fyn mediates signaling pathways involved in neuronal differentiation and plasticity that have been subjected to considerable attention lately, opening the fascinating scenario to target Fyn TK for the development of potential therapeutic interventions for the treatment of CNS injuries and certain neurodegenerative disorders like Alzheimer's disease.
  • 1.8K
  • 05 Nov 2020
Topic Review
Cu Homeostasis in Bacteria
Copper is an essential transition metal which is also toxic to cell.. Organisms have developed sophisticated pathways to import, traffic, store and deliver copper to cuproproteins. They also export its excess outsite of the cell to protect themselves from oxidative stress. The pathways contains specific importers, chaperons, storage proteins and exporters. Expression of the corresponding structural genes is conrolled by copper availability via sensors and response regulation transcription factors described below.
  • 1.8K
  • 08 Feb 2021
Topic Review
O-GlcNAcylation
O-GlcNAcylation is a posttranslational modification that occurs at serine and threonine residues of protein substrates by the addition of O-linked β-d-N-acetylglucosamine (GlcNAc) moiety. Two enzymes are involved in this modification: O-GlcNac transferase (OGT), which attaches the GlcNAc residue to the protein substrate, and O-GlcNAcase (OGA), which removes it. This biological balance is important for many biological processes, such as protein expression, cell apoptosis, and regulation of enzyme activity.
  • 1.8K
  • 04 Mar 2021
Topic Review
Ryanodine Receptor
The ryanodine receptor (RyR) is a Ca2+ release channel in the sarcoplasmic reticulum of skeletal and cardiac muscles and plays a key role in excitation–contraction coupling. The activity of the RyR is regulated by the changes in the level of many intracellular factors, such as divalent cations (Ca2+ and Mg2+), nucleotides, associated proteins, and reactive oxygen species. Since these intracellular factors change depending on the condition of the muscle, e.g., exercise, fatigue, or disease states, the RyR channel activity will be altered accordingly.
  • 1.8K
  • 20 Oct 2021
Topic Review
HER2-Positive Breast Cancer
Up to one-third of all breast cancers are classified as the aggressive HER2-positive subtype, which is associated with a higher risk of recurrence compared to HER2-negative breast cancers. The HER2 hyperactivity associated with this subtype drives tumor growth by up-regulation of mTOR pathways and metabolic adaptation. Combination therapies that simultaneously target HER2 and mTOR improve clinical outcomes compared with HER2 inhibition alone. Drugs that mimic glucose deprivation in HER2-positive breast cancer patients have not been evaluated; however, preclinical studies have shown that the growth of HER2-positive breast tumors is reduced in response to combining the glycolytic inhibitor 2-DG with mTOR inhibitors.
  • 1.8K
  • 02 Jul 2021
Topic Review
Extracellular Signal-Regulated Kinase
Extracellular signal-regulated kinase (ERK5) is an essential regulator of cancer progression, tumor relapse, and poor patient survival. Epithelial to mesenchymal transition (EMT) is a complex oncogenic process, which drives cell invasion, stemness, and metastases. Activators of ERK5, including mitogen-activated protein kinase 5 (MEK5), tumor necrosis factor α (TNF-α), and transforming growth factor-β (TGF-β), are known to induce EMT and metastases in breast, lung, colorectal, and other cancers. Several downstream targets of the ERK5 pathway, such as myocyte-specific enhancer factor 2c (MEF2C), activator protein-1 (AP-1), focal adhesion kinase (FAK), and c-Myc, play a critical role in the regulation of EMT transcription factors SNAIL, SLUG, and β-catenin. Moreover, ERK5 activation increases the release of extracellular matrix metalloproteinases (MMPs), facilitating breakdown of the extracellular matrix (ECM) and local tumor invasion. Targeting the ERK5 signaling pathway using small molecule inhibitors, microRNAs, and knockdown approaches decreases EMT, cell invasion, and metastases via several mechanisms.
  • 1.8K
  • 20 Feb 2021
Topic Review
Yeast Cells in Microencapsulation
Yeasts are uni/multicellular eukaryotic organisms, originally thought to be ascomycetous fungi, but later recognized to also comprise basidiomycetous organisms; more typically, yeasts reproduce asexually (rapid duplication) but can also adopt sexual reproduction.
  • 1.8K
  • 02 Jul 2021
Topic Review
Alignment-Free Approaches
Alignment-free (AF) methodologies have increased in popularity in the last decades as alternative tools to alignment-based (AB) algorithms for performing comparative sequence analyses. They have been especially useful to detect remote homologs within the twilight zone of highly diverse gene/protein families and superfamilies. The most popular alignment-free methodologies, as well as their applications to classification problems, have been described in previous reviews. Despite a new set of graph theory-derived sequence/structural descriptors that have been gaining relevance in the detection of remote homology, they have been omitted as AF predictors when the topic is addressed. Here, we first go over the most popular AF approaches used for detecting homology signals within the twilight zone and then bring out the state-of-the-art tools encoding graph theory-derived sequence/structure descriptors and their success for identifying remote homologs.
  • 1.8K
  • 29 Oct 2020
Topic Review
The Dual Role of Reactive Oxygen Species
The phrase “reactive oxygen species” (ROS) is commonly used to describe the highly reactive free radicals and molecules originating from molecular oxygen. This so-called bi-radical state of oxygen explains its reactivity: one of its electrons can be paired with an external electron with an antiparallel spin, resulting in the production of the highly reactive superoxide radical (O2·−). Since the superoxide radical is weakly basic and highly soluble in water at physiological pH, cellular membranes are relatively impermeable to it. However, O2·− can be converted into membrane-permeable H2O2 by superoxide dismutase (SOD) or protonated to hydroperoxyl radicals (HOO·). Furthermore, O2·− reacts with H2O2 through the Haber–Weiss reaction using iron catalysis, resulting in the formation of highly reactive and cytotoxic hydroxyl radicals (HO·). Furthermore, during the hydroperoxide and polyunsaturated fatty acid metabolism, other types of ROS, namely the peroxyl (ROO·) and alkoxyl (RO·) radicals, are formed as intermediates. On the one hand, high amounts of ROS may damage biomolecules due to their high reactivity. On the other hand—at strictly regulated levels—ROS are essential to maintaining the redox homeostasis of the cells, and they are engaged in many cellular signalling pathways, so their total elimination by the antioxidant system is not expedient.
  • 1.8K
  • 13 May 2022
Topic Review
DNA Methylation and AP-1 Signaling
Epigenetic regulation and modification govern the transcriptional mechanisms that promote disease initiation and progression, but can also control the oncogenic processes, cell signaling networks, immunogenicity, and immune cells involved in anti-inflammatory and anti-tumor responses. 
  • 1.8K
  • 27 Mar 2021
Topic Review
Osteoarthritis
Osteoarthritis (OA) is a most common type of arthritis occur in the aged population. It affects any joint in the body and degenerates the articular cartilage and subchondral bone. Despite the pathophysiology of OA is different, still cartilage resorption is a symbol of osteoarthritis. Matrix metalloproteinases (MMPs) are important proteolytic enzymes that degrade extra-cellular matrix proteins (ECM) in the body. MMPs contribute to the turnover of cartilage and its break down; their levels have increased in the joint tissues of OA patients. Application of chondroprotective drugs neutralize the activities of MMPs. Natural products derived from herbs and plants developed as traditional medicine have paid much attention due to their potential biological effects. Therapeutic value of natural products in OA has increased reputation by presenting clinical impact with insignificant side effects. Several MMPs inhibitor have been used as therapeutic drugs for long time. Recently, different types of compounds have been reviewed for their biological activities. In this review, we summarize numerous natural products for the development as MMPs inhibitors in arthritic diseases and describe the major signaling targets that involved for the treatments of these destructive joint diseases.
  • 1.8K
  • 05 Nov 2020
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