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Topic Review
Biography
Topic Review
Glycosylated Molluscan Hemocyanins
The molluscan hemocyanins have complex carbohydrate structures with predominant N-linked glycans. Determination of glycans and glycopeptides was performed with the most common used methods for the analysis of biomolecules, including peptides and proteins like MALDI-TOF-TOF (time of flight), LC/ESI-MS, LC-Q-trap-MS/MS nano-ESI-MS and others. A novel acidic glycan structures with specific glycosylation positions were observed in Rapana venosa, Helix lucorum, Haliotis tuberculata, e.g. hemocyanins that enable a deeper insight into the glycosylation process.
550
29 Mar 2021
Topic Review
Glycosaminoglycans in Metastatic Renal Cell Carcinoma
Renal cell carcinoma (RCC) makes up the majority of kidney cancers, with a poor prognosis for metastatic RCC (mRCC). Challenges faced in the management of mRCC, include a lack of reliable prognostic markers and biomarkers for precise monitoring of disease treatment, together with the potential risk of toxicity associated with more recent therapeutic options. Glycosaminoglycans (GAGs) are a class of carbohydrates that can be categorized into four main subclasses, viz., chondroitin sulfate, hyaluronic acid, heparan sulfate and keratan sulfate. GAGs are known to be closely associated with cancer progression and modulation of metastasis by modification of the tumor microenvironment. Alterations of expression, composition and spatiotemporal distribution of GAGs in the extracellular matrix (ECM), dysregulate ECM functions and drive cancer invasion.
370
17 Jan 2023
Topic Review
Glutathione/Glutaredoxin in Cellular Redox Homeostasis and Signaling
The tripeptide glutathione (GSH) is the most abundant non-enzymatic antioxidant/nucleophilic molecule in cells. In addition to various metabolic reactions involving GSH and its oxidized counterpart GSSG, oxidative post-translational modification (PTM) of proteins has been a focal point of keen interest in the redox field over the last few decades. In particular, the S-glutathionylation of proteins (protein-SSG formation), i.e., mixed disulfides between GSH and protein thiols, has been studied extensively. This reversible PTM can act as a regulatory switch to interconvert inactive and active forms of proteins, thereby mediating cell signaling and redox homeostasis. The unique architecture of the GSH molecule enhances its relative abundance in cells and contributes to the glutathionyl specificity of the primary catalytic activity of the glutaredoxin enzymes, which play central roles in redox homeostasis and signaling, and in iron metabolism in eukaryotes and prokaryotes under physiological and pathophysiological conditions. The class-1 glutaredoxins are characterized as cytosolic GSH-dependent oxidoreductases that catalyze reversible protein S-glutathionylation specifically, thereby contributing to the regulation of redox signal transduction and/or the protection of protein thiols from irreversible oxidation.
299
08 Aug 2023
Topic Review
Glutamate-Glutamine Cycle
In biochemistry, the glutamate-glutamine cycle is a sequence of events by which an adequate supply of the neurotransmitter glutamate is maintained in the central nervous system. Neurons are unable to synthesize either the neurotransmitter glutamate or γ-aminobutyric acid (GABA) from glucose. Discoveries of glutamine and glutamate pools within intercellular compartments led to suggestions of the glutamate-glutamine cycle working between neurons and astrocytes. The glutamate/GABA-glutamine cycle is a metabolic pathway that describes the release of glutamate or GABA from neurons which are then taken up into astrocytes (star-shaped glial cells). In return, astrocytes release glutamine to be taken up into neurons for use as a precursor to the synthesis of glutamate or GABA.
498
27 Oct 2022
Topic Review
Glucose-Induced Mitochondrial Dysfunction in Diabetic Kidney Disease
The kidney is one of the most energy-demanding organs and, after the heart, has the second highest expression of proteins involved in mitochondrial function and oxygen consumption. The kidney requires energy mainly for solute reabsorption, among other tasks including waste removal, maintenance of electrolyte and fluid balance and acid–base homeostasis. The generation of an ion gradient across the plasma membrane by Na+/K+-ATPase is essential for solute reabsorption. Therefore, mitochondrial dysfunction is postulated to play a central role in the pathogenesis and progression of kidney diseases including DKD. Mitochondrial dysfunction plays an important role in the pathogenesis and progression of diabetic kidney disease (DKD).
487
02 Mar 2022
Topic Review
Glucose 6-P Dehydrogenase in Skeletal Muscle during Exercise
Hypomorphic Glucose 6-P dehydrogenase (G6PD) catalyzes the rate-limiting step in the pentose phosphate pathway (PPP), which provides the precursors of nucleotide synthesis for DNA replication as well as reduced nicotinamide adenine dinucleotide phosphate (NADPH). NADPH is involved in the detoxification of cellular reactive oxygen species (ROS) and de novo lipid synthesis. An association between increased PPP activity and the stimulation of cell growth has been reported in different tissues including the skeletal muscle, liver, and kidney. PPP activity is increased in skeletal muscle during embryogenesis, denervation, ischemia, mechanical overload, the injection of myonecrotic agents, and physical exercise. In fact, the highest relative increase in the activity of skeletal muscle enzymes after one bout of exhaustive exercise is that of G6PD, suggesting that the activation of the PPP occurs in skeletal muscle to provide substrates for muscle repair. The age-associated loss in muscle mass and strength leads to a decrease in G6PD activity and protein content in skeletal muscle. G6PD overexpression in Drosophila Melanogaster and mice protects against metabolic stress, oxidative damage, and age-associated functional decline, and results in an extended median lifespan.
1.0K
02 Nov 2022
Topic Review
Gliomas
Gliomas are a group of primary tumors of the central nervous system (CNS) originating from glial cells. It was estimated that gliomas account for nearly a quarter of all primary CNS tumors. The management of malignant gliomas poses several challenges, in part due to the heterogeneous and resistant nature of neoplasm, as well as the obstacles faced when administering high-dose radiation and chemotherapy in tissue as vulnerable as that of the CNS. These difficulties are due to the tumor’s aggressiveness and the adverse effects of radio/chemotherapy on the brain. Stem cell therapy is an exciting area of research being explored for several medical issues.
546
24 Mar 2021
Topic Review
Glioblastoma-Specific Strategies of Vascularization
Angiogenesis has long been implicated as a crucial process in Glioblastoma (GBM) growth and progression. GBM can adopt several strategies to build up its abundant and aberrant vasculature. Targeting GBM angiogenesis has gained more and more attention in anti-cancer therapy, and many strategies have been developed to interfere with this hallmark.
427
17 Oct 2022
Topic Review
Glioblastoma Microenvironment and Invasiveness
Glioblastoma (GBM) is the most common and malignant primary brain cancer in adults. Without treatment the mean patient survival is approximately 6 months, which can be extended to 15 months with the use of multimodal therapies. The low effectiveness of GBM therapies is mainly due to the tumor infiltration into the healthy brain tissue, which depends on GBM cells’ interaction with the tumor microenvironment (TME). The interaction of GBM cells with the TME involves cellular components such as stem-like cells, glia, endothelial cells, and non-cellular components such as the extracellular matrix, enhanced hypoxia, and soluble factors such as adenosine, which promote GBM’s invasiveness.
306
30 Jun 2023
Topic Review
Glial Cells in Physiological and Pathological States
Glial cells are the most abundant and widely distributed cells that maintain cerebral homeostasis in the central nervous system. They mainly include microglia, astrocytes, and the oligodendrocyte lineage cells. Moreover, glial cells may induce pathological changes, such as inflammatory responses, demyelination, and disruption of the blood–brain barrier, to regulate the occurrence and development of neurological diseases through various molecular mechanisms.
841
29 Aug 2022
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