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Topic Review
Blood-Brain Barrier: Functionalised Chitosan
The major impediment to the delivery of therapeutics to the brain is the presence of the blood-brain barrier (BBB). The BBB allows for the entrance of essential nutrients while excluding harmful substances, including most therapeutic agents; hence, brain disorders, especially tumors, are very difficult to treat. Chitosan is a well-researched polymer that offers advantageous biological and chemical properties, such as mucoadhesion and ease of functionalization. Chitosan-based nanocarriers (CsNCs) establish ionic interactions with the endothelial cells, facilitating the crossing of drugs through the BBB by adsorptive mediated transcytosis. This process is further enhanced by modifications of the structure of chitosan, owing to the presence of reactive amino and hydroxyl groups. Finally, by permanently binding ligands or molecules, such as antibodies or lipids, CsNCs have shown a boosted passage through the BBB, in both in vivo and in vitro studies which will be discussed in this review.
  • 2.4K
  • 21 Nov 2020
Topic Review
Peripheral Muscle Fatigue
Muscle fatigue is defined as a decrease in maximal force or power generated in response to contractile activity, and it is a risk factor for the development of musculoskeletal injuries. One of the many stressors imposed on skeletal muscle through exercise is the increased production of reactive oxygen species (ROS) and reactive nitrogen species (RNS), which intensifies as a function of exercise intensity and duration. The progressive reduction in muscle fibers’ ability to generate force originates at different levels of the motor system and can be categorized into two types, namely, central and peripheral fatigue. Peripheral mechanisms of fatigue refer to activity-induced mechanical failure through processes at or distal to neuromuscular junctions, so they can be attributed to neuromuscular transmission and excitation–contraction coupling.
  • 2.4K
  • 10 Mar 2023
Topic Review
Acetylation
Acetylation, also known as acetylation or acetylation, refers to the chemical reaction of adding an acetyl functional group to an organic compound. Conversely, the reaction in which the acetyl group is removed is called deacetylation or deacetylation. Acetylation of proteins is a post-translational modification.
  • 2.4K
  • 16 Nov 2022
Topic Review
Red Blood Cells Metabolism beyond Glycolysis
Red blood cells (RBC) are the most abundant cell in the human body, with a central role in oxygen transport and its delivery to tissues. The relative simplicity of RBCs, as historically perceived, has attracted multiple efforts to leverage them as a model of simplified human cell metabolism. Indeed, RBCs exclusively rely on glycolysis (Embden–Meyerhof–Parnas pathway) to generate high-energy phosphate compounds, such as adenosine triphosphate (ATP)—whose main source in other cells is oxidative phosphorylation in mitochondria.
  • 2.3K
  • 13 Jul 2023
Topic Review
Sigma-2 Receptor
Sigma-1 and sigma-2 receptor have different pharmacological profiles. In the past two decades,  the biological and pharmacological properties of the sigma-1 receptor has been well studied, however, little is known about the sigma-2 receptor. The molecular identity of Sigma-2 receptor has been proposed as TMEM97, but more work has to been done to address questions regarding our current knowledge of Sigma-2 pharmacology. Recently, the sigma-2 receptor is recognized as a novel regulator influencing cellular cholesterol homeostasis. Additionally, cholesterol homeostasis was disrupted in tumors and Alzheimer’s disease, and the sigma-2 receptor ligands have showed promise to treat tumors and AD. 
  • 2.3K
  • 08 Dec 2020
Topic Review
Rosemary
Rosemary (Rosemarinus officinalis L.) belongs to the Lamiaceae family and is native to the Mediterranean region and part of Asia. It is the most well-known plant with antioxidant activity, and the only one currently approved as natural antioxidant in EU (E-392). The main antioxidant components and the extraction procedures are reviewed in the present work.
  • 2.3K
  • 30 Jun 2021
Topic Review
Biogenesis and Composition of RBC-Derived Extracellular Vesicles
Extracellular vesicles (EVs) are cell-derived membrane vesicles that represent an endogenous mechanism for intercellular communication. The original classification distinguished exosomes (nano-sized vesicles with a diameter in the range of 30 to 120 nm), originating from the formation of multivesicular bodies, microvesicles, which are formed by cell membrane budding, and apoptotic bodies, derived from dying cells. 
  • 2.3K
  • 20 Feb 2023
Topic Review
Soybean Isoflavones
Soybeans are rich in proteins and lipids and have become a staple part of the human diet. Besides their nutritional excellence, they have also been shown to contain various functional components, including isoflavones, and have consequently received increasing attention as a functional food item. Isoflavones are structurally similar to 17-β-estradiol and bind to estrogen receptors (ERα and ERβ). The estrogenic activity of isoflavones ranges from a hundredth to a thousandth of that of estrogen itself. Isoflavones play a role in regulating the effects of estrogen in the human body, depending on the situation. Thus, when estrogen is insufficient, isoflavones perform the functions of estrogen, and when estrogen is excessive, isoflavones block the estrogen receptors to which estrogen binds, thus acting as an estrogen antagonist. In particular, estrogen antagonistic activity is important in the breast, endometrium, and prostate, and such antagonistic activity suppresses cancer occurrence. 
  • 2.3K
  • 06 Jul 2021
Topic Review
The Cannabis Terpenes
Terpenes are the primary constituents of essential oils and are responsible for the aroma characteristics of cannabis. Together with the cannabinoids, terpenes illustrate synergic and/or entourage effect and their interactions have only been speculated in for the last few decades. Hundreds of terpenes are identified that allude to cannabis sensory attributes, contributing largely to the consumer’s experiences and market price. They also enhance many therapeutic benefits, especially as aromatherapy.
  • 2.3K
  • 16 Dec 2020
Topic Review
Cannabis Sativa Revisited
Critically ill patients with sepsis require a multidisciplinary approach, as this situation implies multiorgan distress, with most of the bodily biochemical and cellular systems being affected by the condition. Moreover, sepsis is characterized by a multitude of biochemical interactions and by dynamic changes of the immune system. At the moment, there is a gap in our understanding of the cellular, genetic, and molecular mechanisms involved in sepsis. One of the systems intensely studied in recent years is the endocannabinoid signaling pathway, as light was shed over a series of important interactions of cannabinoid receptors with biochemical pathways, specifically for sepsis. Furthermore, a series of important implications on inflammation and the immune system that are induced by the activity of cannabinoid receptors stimulated by the delta-9-tetrahydrocannabinol (Δ9-THC) and cannabidiol (CBD) have been noticed. One of the most important is their ability to reduce the biosynthesis of pro-inflammatory mediators and the modulation of immune mechanisms. Different studies have reported that cannabinoids can reduce oxidative stress at mitochondrial and cellular levels. In detail, the entry shows the important mechanisms modulated by the endocannabinoid signaling pathway, as well as of the molecular and cellular links it has with sepsis. At the same time, the possible implications of cannabinoids in the most important biological pathways involved in sepsis, such as inflammation, redox activity, immune system, and epigenetic expression will be presented.
  • 2.3K
  • 04 Jul 2022
Topic Review
α-Synuclein Aggregation in Treatment of Parkinson’s Disease
Parkinson’s disease, the second most common neurodegenerative disorder worldwide, is characterized by the accumulation of protein deposits in the dopaminergic neurons. These deposits are primarily composed of aggregated forms of α-Synuclein (α-Syn). PD is a complex pathology initially associated with motor deficiencies, as a result of an acute neuronal loss in substantia nigra pars compacta (SNc), with a significant dopaminergic (DA) impairment.
  • 2.3K
  • 31 Mar 2023
Topic Review
Inorganic Nanoparticles for Cancer Treatment
The application of porphyrins and their derivatives have been investigated extensively over the past years for phototherapy cancer treatment. Phototherapeutic Porphyrins have the ability to generate high levels of reactive oxygen with a low dark toxicity and these properties have made them robust photosensitizing agents. In recent years, Porphyrins have been combined with various nanomaterials in order to improve their bio-distribution. These combinations allow for nanoparticles to enhance photodynamic therapy (PDT) cancer treatment and adding additional nanotheranostics (photothermal therapy—PTT) as well as enhance photodiagnosis (PDD) to the reaction. This review examines various porphyrin-based inorganic nanoparticles developed for phototherapy nanotheranostic cancer treatment over the last three years (2017 to 2020). Furthermore, current challenges in the development and future perspectives of porphyrin-based nanomedicines for cancer treatment are also highlighted.
  • 2.3K
  • 28 Oct 2020
Topic Review
m6A Demethylases Inhibitors
N6-methyladenosine (m6A) is a post-transcriptional RNA modification and one of the most abundant types of RNA chemical modifications. m6A functions as a molecular switch and is involved in a range of biomedical aspects, including cardiovascular diseases, the central nervous system, and cancers.
  • 2.3K
  • 06 Jun 2022
Topic Review
Galectin-3 in Cardiovascular Diseases
Galectin-3 (Gal-3) belongs to a lectin family, acting as a galactoside-binding protein involved in many biological processes, such as controlling cell–cell and cell–matrix interactions, adhesion, proliferation, apoptosis, pre-mRNA splicing, immunity and inflammation.
  • 2.3K
  • 22 Dec 2020
Topic Review
Boron Essentiality in Humans and Animals
Boron (B) is considered a prebiotic chemical element with a role in both the origin and evolution of life, as well as an essential micronutrient for some bacteria, plants, fungi, and algae. B has beneficial effects on the biological functions of humans and animals, such as reproduction, growth, calcium metabolism, bone formation, energy metabolism, immunity, and brain function. Naturally organic B (NOB) species may become promising novel prebiotic candidates. NOB-containing compounds have been shown to be essential for the symbiosis between organisms from different kingdoms. New insights into the key role of NOB species in the symbiosis between human/animal hosts and their microbiota will influence the use of natural B-based colon-targeting nutraceuticals. The mechanism of action (MoA) of NOB species is related to the B signaling molecule (autoinducer-2-borate (AI-2B)) as well as the fortification of the colonic mucus gel layer with NOB species from B-rich prebiotic diets. Both the microbiota and the colonic mucus gel layer can become NOB targets. The evidence supporting the essentiality of the NOB species in the symbiosis between the microbiota and the human/animal hosts is reviewed, with the stated aim of highlighting the MoA and targets of these species.
  • 2.3K
  • 13 Sep 2022
Topic Review
The HD-Domain Metalloprotein Superfamily
The histidine–aspartate (HD)-domain protein superfamily contains metalloproteins that share common structural features but catalyze vastly different reactions ranging from oxygenation to hydrolysis. This chemical diversion is afforded by (i) their ability to coordinate most biologically relevant transition metals in mono-, di-, and trinuclear configurations, (ii) sequence insertions or the addition of supernumerary ligands to their active sites, (iii) auxiliary substrate specificity residues vicinal to the catalytic site, (iv) additional protein domains that allosterically regulate their activities or have catalytic and sensory roles, and (v) their ability to work with protein partners. More than 500 structures of HD-domain proteins are available to date that lay out unique structural features which may be indicative of function. In this respect, we describe the three known classes of HD-domain proteins (hydrolases, oxygenases, and lyases) and identify their apparent traits with the aim to portray differences in the molecular details responsible for their functional divergence and reconcile existing notions that will help assign functions to yet-to-be characterized proteins.
  • 2.3K
  • 29 Oct 2020
Topic Review
Natural Products from Madagascar
Natural products with biological activity represent a primary source of commodities ranging from human nutrition to therapy. Also they may represent cosmetic principles and/or recreational tools. These natural means have been used by mankind for centuries, if not millennia. They are commonly used all over the world in socio-economical contexts, but are particularly attractive in disadvantaged areas or economically emerging situations all over the world because of their accessibility and low cost/use ratio.
  • 2.3K
  • 08 Oct 2021
Topic Review
Doxorubicin
The antibiotic doxorubicin is often used as an anti-neoplastic drug; however, many patients showed very unpleasant side-effects. Previous studies have demonstrated that dietary substances such as Aloe arborescens, Annona muricata, Morinda citrifolia, Beta rubra, Scutellaria baicalensis, and Vaccinium myrtillus may have anti-oxidant, anti-proliferative, and anti-inflammatory effects. The purpose of this study was to investigate the protective effects of a mixture of these components in an experimental model of doxorubicin toxicity. Rats (n = 30) received doxorubicin (5 mg/kg/day) for 4 weeks and were randomized to receive the dietary mixture 2 hours following the first doxorubicin injection and until the end of the experiment. Animals were killed following 4 weeks, and blood, liver, and heart were collected for further analysis. The dietary supplement improved the depressed body weight and food consumption induced by DOX. In addition, the nutraceutical mixture reduced oxidative stress, ameliorated the morphological score, and preserved liver and heart structure, demonstrating a protective effect. These data show for the first time that the mixture of Aloe arborescens, Annona muricata, Morinda citrifolia, Beta rubra, Scutellaria baicalensis, and Vaccinium myrtillus may be useful to reduce the side effects following treatment with doxorubicin, and might ameliorate the quality of life of patients following chemotherapy.
  • 2.3K
  • 06 Nov 2020
Topic Review
Melanogenesis in Immune Systems
Melanocytes and melanin play a wide range of roles such as adsorption of metals, thermoregulation, and protection from foreign enemies by camouflage.
  • 2.3K
  • 14 Jan 2021
Topic Review
β-glucosidases
β-glucosidases (EC. 3.2.1.21) are enzymes that hydrolyze glucosidic bonds of oligosaccharides, in special disaccharides, such as cellobiose, realizing glucose at the end of the process. They are highly used in second-generation biofuel production. 
  • 2.3K
  • 29 Jan 2024
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