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Topic Review
Mitochondrial Disease
Mitochondrial disease is a group of disorders caused by mitochondrial dysfunction. Mitochondria are the organelles that generate energy for the cell and are found in every cell of the human body except red blood cells. They convert the energy of food molecules into the ATP that powers most cell functions. Mitochondrial diseases take on unique characteristics both because of the way the diseases are often inherited and because mitochondria are so critical to cell function. A subclass of these diseases that have neuromuscular symptoms are known as mitochondrial myopathies.
  • 2.2K
  • 25 Oct 2022
Topic Review
Mitochondrion Structure and Function
Mitochondria are subcellular organelles involved in essential cellular functions, including cytosolic calcium regulation, cell apoptosis, and reactive oxygen species production. They are the site of important biochemical pathways, including the tricarboxylic acid cycle, parts of the ureagenesis cycle, or haem synthesis.
  • 2.2K
  • 15 Mar 2023
Topic Review
Protein Glycosylation
Protein glycosylation is a highly conserved post-translational modification among organisms. It plays fundamental roles in many biological processes, ranging from protein trafficking and cell adhesion to host–pathogen interactions. According to the amino acid side chain atoms to which glycans are linked, protein glycosylation can be divided into two major categories: N-glycosylation and O-glycosylation. However, there are other types of modifications such as the addition of GPI to the C-terminal end of the protein. Besides the importance of glycoproteins in biological functions, they are a major component of the fungal cell wall and plasma membrane and contribute to pathogenicity, virulence, and recognition by the host immunity. Given that this structure is absent in host mammalian cells, it stands as an attractive target for developing selective compounds for the treatment of fungal infections.
  • 2.2K
  • 27 Oct 2021
Topic Review
Warburg Effect
Otto Warburg discovered that cancer cells use a fermentative rather than oxidative metabolism even though the former is more inefficient in terms of energy production per molecule of glucose. Cancer cells increase the use of this fermentative metabolism even in the presence of oxygen, and this process is called aerobic glycolysis or the Warburg effect.
  • 2.2K
  • 14 Jun 2023
Topic Review
Cyclins and Cyclin-Dependent Kinases in Gastric Cancer
Gastric cancer predominantly occurs in adenocarcinoma form and is characterized by uncontrolled growth and metastases of gastric epithelial cells. The growth of gastric cells is regulated by the action of several major cell cycle regulators including Cyclins and Cyclin-dependent kinases (CDKs), which act sequentially to modulate the life cycle of a living cell. It has been reported that inadequate or over-activity of these molecules leads to disturbances in cell cycle dynamics, which consequently results in gastric cancer development.
  • 2.2K
  • 08 Feb 2023
Topic Review
Retinoic Acid
The retinoids are a group of compounds including vitamin A and its active metabolite all-trans-retinoic acid (ATRA). Retinoids regulate a variety of physiological functions in multiple organ systems, are essential for normal immune competence, and are involved in the regulation of cell growth and differentiation. Vitamin A derivatives have held promise in cancer treatment and ATRA is used in differentiation therapy of acute promyelocytic leukemia (APL). ATRA and other retinoids have also been successfully applied in a variety of dermatological conditions such as skin cancer, psoriasis, acne, and ichthyosis. Moreover, modulation of retinoic acid receptors and retinoid X (or rexinoid) receptors function may affect dermal cells. The studies using complex genetic models with various combinations of retinoic acid receptors (RARs) and retinoid X (or rexinoid) receptors (RXRs) indicate that retinoic acid and its derivatives have therapeutic potential for a variety of serious dermatological disorders including some malignant conditions.
  • 2.2K
  • 28 Dec 2020
Topic Review
The Sumoylation Pathway
Post-translational modifications (PTMs) are key regulators of most biological processes. Besides phosphorylation, methylation, acetylation and others, covalent modification of proteins by small polypeptides of the ubiquitin-like modifiers (UBLs) family have gained importance. Among UBLs, the small ubiquitin-like modifier (SUMO), of ~90 amino acids and discovered in the nineties, has proven to regulate most cellular processes. The sumoylation pathway is quite similar to the ubiquitination pathway, but there is its own set of enzymes for modification by SUMO.
  • 2.2K
  • 25 Jul 2022
Topic Review
PARP Inhibitor-Induced Synthetic Lethality
The advanced development of synthetic lethality has opened the doors for specific anti-cancer medications of personalized medicine and efficient therapies against cancers. One of the most popular approaches being investigated is targeting DNA repair pathways as the implementation of the poly-ADP ribose polymerase 1 (PARP) inhibitor (PARPi) into individual or combinational therapeutic schemes. Such treatment has been effectively employed against homologous recombination-defective solid tumors as well as hematopoietic malignancies. In the most common aspect of precision medicine, PARPi triggers synthetic lethality in cancer cells harboring BRCA1/2 mutations/deficiencies. 
  • 2.2K
  • 05 Dec 2022
Topic Review
Induction of Accelerated Aging in a Mouse Model
With the global increase of the elderly population, the improvement of the treatment for various aging-related diseases and the extension of a healthy lifespan have become some of the most important current medical issues. In order to understand the developmental mechanisms of aging and aging-related disorders, animal models are essential to conduct relevant studies. Among them, mice have become one of the most prevalently used model animals for aging-related studies due to their high similarity to humans in terms of genetic background and physiological structure, as well as their short lifespan and ease of reproduction. 
  • 2.1K
  • 05 May 2022
Topic Review
Cofilin and Actin Dynamics
Proteins of the actin depolymerizing factor (ADF)/cofilin family are ubiquitous among eukaryotes and are essential regulators of actin dynamics and function. Mammalian neurons express cofilin-1 as the major isoform, but ADF and cofilin-2 are also expressed. All isoforms bind preferentially and cooperatively along ADP-subunits in F-actin, affecting the filament helical rotation, and when either alone or when enhanced by other proteins, promotes filament severing and subunit turnover.
  • 2.1K
  • 25 Oct 2021
Topic Review
Human Neural Stem Cell Systems
       Building and functioning of the human brain requires the precise orchestration and execution of myriad molecular and cellular processes, across a multitude of cell types and over an extended period of time. Neural Stem Cells (NSCs) represent the heart of these processes, since they increase the pool of neural progenitors and are the founders of all the neural progeny which will constitute the adult human brain.
  • 2.1K
  • 30 Oct 2020
Topic Review
Cancer Stem Cells
Cancer Stem Cells (CSCs) is a subset of cancer cells with the ability to self-renew and to differentiate into non-CSC cancer cells within the tumor mass. The CSC field was shaped by great research done on hematopoietic stem cells (HSCs). HSCs are hierarchically arranged with HSCs being the founder cells that undergo asymmetric cell division giving rise to differentiated daughter cells and one quiescent stem cell with self-renewal abilities. CSCs are a subpopulation of cancer cells known to be resistant to therapy and cause metastasis. CSCs have been characterized in many cancers with data illustrating that CSCs display great abilities to self-renew, resist therapies due to enhanced epithelial to mesenchymal (EMT) properties, enhanced expression of ATP-binding cassette (ABC) membrane drug transporters, activation of several survival signaling pathways and increased immune evasion as well as DNA repair mechanisms. CSCs also display great heterogeneity with the consequential lack of specific CSC markers presenting a great challenge to their targeting.
  • 2.1K
  • 15 May 2023
Topic Review
TDP-43 Role in Chromatin Remodeling and Transcription
TDP-43 gained momentum in the neurodegeneration field when it was first discovered that almost all amyotrophic lateral sclerosis (ALS) cases and as many as half of frontotemporal dementia (FTD) cases present pathological ubiquitinated inclusions of TDP-43. Its involvement in chromatin silencing and nuclear/cytoplasmic shuttling constitute convergent key findings from several biological screens, and several crucial epigenetic factors appear to be able to modify TDP-43-induced degeneration. TDP-43 activity at the chromatin level and its implication in the regulation of DNA transcription and stability -such as DNA repair and regulation of retrotransposons activity- are further supported by a continuously growing amount of studies.
  • 2.1K
  • 19 Sep 2023
Topic Review
Methods to Establish a 3D Cell Culture
The clear potential of three-dimensional (3D) systems to provide new models suitable for studying cell interactions in both basic and more specialized research, revolutionizing cell culture technology, and offering alternative methods for animal experimentation, has prompted the scientific community to develop different efficient methods to establish 3D cell cultures, all of which, in turn, affect 3D model characteristics. These techniques can be divided into two major categories: scaffold-free systems and scaffold-based systems. Scaffold-free systems are based on the self-aggregation capability of some cell types, which can be encouraged using specific cell plates and/or physical parameters that avoid cell attachment. On the other hand, in scaffold-based systems, cells are seeded in natural or synthetic materials, allowing cell proliferation, aggregation, and 3D organization.
  • 2.1K
  • 02 Aug 2023
Topic Review
The Glyoxalase System
The glyoxalase system was discovered over a hundred years ago and since then it has been claimed to provide the role of an indispensable enzyme system in order to protect cells from a toxic byproduct of glycolysis.
  • 2.1K
  • 27 Jan 2021
Topic Review
Tau Isoforms
Tau was first described as a natively unfolded microtubule-associated protein. In fact, its main function is to promote the assembly of microtubules and stabilize their structure. However, Tau proteins have a variety of other functions, which include maintaining the structural integrity of neurons, contributing to signal transmission between neurons, and axonal transport. Tau also plays a role in regulating myelination, iron homeostasis, and neurogenesis and may also support synaptic plasticity. Other roles attributed to Tau are gene expression regulation, DNA protection, genome stability, microRNA activity, RNA protection, RNA metabolism, and protein synthesis.
  • 2.1K
  • 27 Dec 2022
Topic Review
Receptor Tyrosine Kinases
The receptor tyrosine kinases (RTKs) are a large family of cell-surface receptors, which are essential components of signal transduction pathways. There are more than fifty human RTKs that can be grouped into multiple RTK subfamilies. RTKs mediate cellular signaling transduction, and they play important roles in the regulation of numerous cellular processes. The dysregulation of RTK signaling is related to various human diseases, including cancers. The proteolytic cleavage phenomenon has frequently been found among multiple receptor tyrosine kinases. More and more information about proteolytic cleavage in RTKs has been discovered, providing rich insight.
  • 2.1K
  • 16 May 2021
Topic Review
Transposon
Transposons are sequences of DNA that can move around to different positions within the genome of a single cell, a process called transposition. In the process, they can cause mutations and change the amount of DNA in the genome. Transposons are also called "jumping genes" or "mobile genetic elements". Discovered by Barbara McClintock early in her career, the topic went on to be a Nobel winning work in 1983. There are a variety of mobile genetic elements, and they can be grouped based on their mechanism of transposition. Class I mobile genetic elements, or retrotransposons, move in the genome by being transcribed to RNA and then back to DNA by reverse transcriptase, while class II mobile genetic elements move directly from one position to another within the genome using a transposase to "cut and paste" them within the genome. Transposons are very useful to researchers as a means to alter DNA inside of a living organism. Transposons make up a large fraction of genome sizes which is evident through the C-values of eukaryotic species. As an example about 45% of the human genome is composed of transposons and their defunct remnants.
  • 2.1K
  • 23 Nov 2022
Topic Review
Human Dental Pulp Stem Cells
Human dental pulp stem cells (hDPSCs) are adult mesenchymal stem cells (MSCs) obtained from dental pulp and derived from the neural crest. They can differentiate into odontoblasts, osteoblasts, chondrocytes, adipocytes and nerve cells, and they play a role in tissue repair and regeneration.
  • 2.1K
  • 29 May 2023
Topic Review
Sulfate Reduction in Intestinal Bacteria
Sulfate is present in foods, beverages, and drinking water. Its reduction and concentration in the gut depend on the intestinal microbiome activity, especially sulfate-reducing bacteria (SRB), which can be involved in inflammatory bowel disease (IBD). Assimilatory sulfate reduction (ASR) is present in all living organisms. In this process, sulfate is reduced to hydrogen sulfide and then included in cysteine and methionine biosynthesis. In contrast to assimilatory sulfate reduction, the dissimilatory process is typical for SRB. A terminal product of this metabolism pathway is hydrogen sulfide, which can be involved in gut inflammation and also causes problems in industries (due to corrosion effects).
  • 2.1K
  • 26 May 2021
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