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3.
Food Chem ; 430: 137092, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37544153

RESUMO

Difficulties in identification of drug residues in food products arise due to their trace amounts in complex matrices. An eco-friendly and low-cost agarose-chitosan-magnetic graphene oxide based adsorbent was synthesized and employed for determination of aminoglycosides from chicken egg samples through HPLC. Synthesized adsorbent was characterized by SEM, FTIR, XRD, and VSM. Among two investigated aminoglycosides, streptomycin was derivatized with ninhydrin while gentamicin was detected without its derivatization. Impact of experimental variables such as adsorbent dose, extraction time, temperature, pH, and analyte concentration on extraction efficiency was investigated. Statistical analysis for determination of streptomycin and gentamicin demonstrated excellent linearity in the range of 0.2-1.6 µg kg-1, LOQ of 0.3 and 0.6 µg kg-1 for streptomycin and gentamicin, respectively and LOD of 0.1 and 0.19 µg kg-1 for streptomycin and gentamicin, respectively with RSD of 2.5% and recoveries up to 94%. Regeneration studies revealed that composite film can be used four times without considerable reduction in its extraction efficiency.


Assuntos
Ovos , Extração em Fase Sólida , Magnetismo , Extração em Fase Sólida/métodos , Animais , Galinhas , Sefarose/química , Quitosana/química , Aminoglicosídeos/química , Vibração
4.
Food Chem ; 430: 136988, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37544154

RESUMO

Pea (Pisum sativum L.) protein hydrolysate (PPH) has a bitter taste, which has limited its use in food industry. γ-Glutamylation is used to debitter PPH. Results showed that the bitterness of PPH was decreased significantly due to the formation of γ-glutamyl peptides, including 16 γ-[Glu](n=1/2)-amino acids (AAs) and 8 newly discovered γ-glutamyl tripeptides (γ-Glu-Asn-Phe, γ-Glu-Leu-Val, γ-Glu-Leu-Tyr, γ-Glu-Gly-Leu, γ-Glu-Gly-Phe, γ-Glu-Gly-Tyr, γ-Glu-Val-Val, and γ-Glu-Gln-Tyr). Their total production concentrations were 27.25 µmol/L and 77.76 µmol/L, respectively. The γ-Glu-AA-AAs presented an umami-enhancing, salty-enhancing, and kokumi taste when their concentration reached 1.67 ± 0.20 âˆ¼ 2.07 ± 0.20, 1.65 ± 0.25 âˆ¼ 2.29 ± 0.45 and 0.68 ± 0.19 âˆ¼ 1.03 ± 0.22 mmol/L, respectively. The γ-Glu-AA-AAs exhibited a kokumi taste by entering the Venus flytrap (VFT) of the calcium-sensing receptor and interacting with Ser147, Ala168, and Ser170. γ-Glu-AA-AAs can enhance the umaminess of Monosodium Glutamate (MSG) as they can enter the binding pocket of the taste receptor type 1 subunit 3 (T1R3)-MSG complex.


Assuntos
Ervilhas , Paladar , Simulação por Computador , Ervilhas/química , Proteínas de Ervilha/química , Hidrolisados de Proteína/química , Modelos Moleculares , Estrutura Terciária de Proteína
5.
Neural Regen Res ; 19(1): 55-61, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37488844

RESUMO

Extracellular vesicles are released by all cell types and contain proteins, microRNAs, mRNAs, and other bioactive molecules. Extracellular vesicles play an important role in intercellular communication and in the modulation of the immune system and neuroinflammation. The cargo of extracellular vesicles (e.g., proteins and microRNAs) is altered in pathological situations. Extracellular vesicles contribute to the pathogenesis of many pathologies associated with sustained inflammation and neuroinflammation, including cancer, diabetes, hyperammonemia and hepatic encephalopathy, and other neurological and neurodegenerative diseases. Extracellular vesicles may cross the blood-brain barrier and transfer pathological signals from the periphery to the brain. This contributes to inducing neuroinflammation and cognitive and motor impairment in hyperammonemia and hepatic encephalopathy and in neurodegenerative diseases. The mechanisms involved are beginning to be understood. For example, increased tumor necrosis factor α in extracellular vesicles from plasma of hyperammonemic rats induces neuroinflammation and motor impairment when injected into normal rats. Identifying the mechanisms by which extracellular vesicles contribute to the pathogenesis of these diseases will help to develop new treatments and diagnostic tools for their easy and early detection. In contrast, extracellular vesicles from mesenchymal stem cells have therapeutic utility in many of the above pathologies, by reducing inflammation and neuroinflammation and improving cognitive and motor function. These extracellular vesicles recapitulate the beneficial effects of mesenchymal stem cells and have advantages as therapeutic tools: they are less immunogenic, may not differentiate to malignant cells, cross the blood-brain barrier, and may reach more easily target organs. Extracellular vesicles from mesenchymal stem cells have beneficial effects in models of ischemic brain injury, Alzheimer's and Parkinson's diseases, hyperammonemia, and hepatic encephalopathy. Extracellular vesicles from mesenchymal stem cells modulate the immune system, promoting the shift from a pro-inflammatory to an anti-inflammatory state. For example, extracellular vesicles from mesenchymal stem cells modulate the Th17/Treg balance, promoting the anti-inflammatory Treg. Extracellular vesicles from mesenchymal stem cells may also act directly in the brain to modulate microglia activation, promoting a shift from a pro-inflammatory to an anti-inflammatory state. This reduces neuroinflammation and improves cognitive and motor function. Two main components of extracellular vesicles from mesenchymal stem cells which contribute to these beneficial effects are transforming growth factor-ß and miR-124. Identifying the mechanisms by which extracellular vesicles from mesenchymal stem cells induce the beneficial effects and the main molecules (e.g., proteins and mRNAs) involved may help to improve their therapeutic utility. The aims of this review are to summarize the knowledge of the pathological effects of extracellular vesicles in different pathologies, the therapeutic potential of extracellular vesicles from mesenchymal stem cells to recover cognitive and motor function and the molecular mechanisms for these beneficial effects on neurological function.

6.
Neural Regen Res ; 19(1): 124-131, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37488853

RESUMO

Alzheimer's disease is the most common cause of dementia globally with an increasing incidence over the years, bringing a heavy burden to individuals and society due to the lack of an effective treatment. In this context, sirtuin 2, the sirtuin with the highest expression in the brain, has emerged as a potential therapeutic target for neurodegenerative diseases. This review summarizes and discusses the complex roles of sirtuin 2 in different molecular mechanisms involved in Alzheimer's disease such as amyloid and tau pathology, microtubule stability, neuroinflammation, myelin formation, autophagy, and oxidative stress. The role of sirtuin 2 in all these processes highlights its potential implication in the etiology and development of Alzheimer's disease. However, its presence in different cell types and its enormous variety of substrates leads to apparently contradictory conclusions when it comes to understanding its specific functions. Further studies in sirtuin 2 research with selective sirtuin 2 modulators targeting specific sirtuin 2 substrates are necessary to clarify its specific functions under different conditions and to validate it as a novel pharmacological target. This will contribute to the development of new treatment strategies, not only for Alzheimer's disease but also for other neurodegenerative diseases.

7.
Neural Regen Res ; 19(1): 158-159, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37488861
10.
Neural Regen Res ; 19(1): 43-48, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37488842

RESUMO

Adult neural stem cells are neurogenesis progenitor cells that play an important role in neurogenesis. Therefore, neural regeneration may be a promising target for treatment of many neurological illnesses. The regenerative capacity of adult neural stem cells can be characterized by two states: quiescent and active. Quiescent adult neural stem cells are more stable and guarantee the quantity and quality of the adult neural stem cell pool. Active adult neural stem cells are characterized by rapid proliferation and differentiation into neurons which allow for integration into neural circuits. This review focuses on differences between quiescent and active adult neural stem cells in nutrition metabolism and protein homeostasis. Furthermore, we discuss the physiological significance and underlying advantages of these differences. Due to the limited number of adult neural stem cells studies, we referred to studies of embryonic adult neural stem cells or non-mammalian adult neural stem cells to evaluate specific mechanisms.

14.
Neural Regen Res ; 19(1): 116-123, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37488852

RESUMO

Repetitive transcranial magnetic stimulation has been increasingly studied in different neurological diseases, and although most studies focus on its effects on neuronal cells, the contribution of non-neuronal cells to the improvement triggered by repetitive transcranial magnetic stimulation in these diseases has been increasingly suggested. To systematically review the effects of repetitive magnetic stimulation on non-neuronal cells two online databases, Web of Science and PubMed were searched for the effects of high-frequency-repetitive transcranial magnetic stimulation, low-frequency-repetitive transcranial magnetic stimulation, intermittent theta-burst stimulation, continuous theta-burst stimulation, or repetitive magnetic stimulation on non-neuronal cells in models of disease and in unlesioned animals or cells. A total of 52 studies were included. The protocol more frequently used was high-frequency-repetitive magnetic stimulation, and in models of disease, most studies report that high-frequency-repetitive magnetic stimulation led to a decrease in astrocyte and microglial reactivity, a decrease in the release of pro-inflammatory cytokines, and an increase of oligodendrocyte proliferation. The trend towards decreased microglial and astrocyte reactivity as well as increased oligodendrocyte proliferation occurred with intermittent theta-burst stimulation and continuous theta-burst stimulation. Few papers analyzed the low-frequency-repetitive transcranial magnetic stimulation protocol, and the parameters evaluated were restricted to the study of astrocyte reactivity and release of pro-inflammatory cytokines, reporting the absence of effects on these parameters. In what concerns the use of magnetic stimulation in unlesioned animals or cells, most articles on all four types of stimulation reported a lack of effects. It is also important to point out that the studies were developed mostly in male rodents, not evaluating possible differential effects of repetitive transcranial magnetic stimulation between sexes. This systematic review supports that through modulation of glial cells repetitive magnetic stimulation contributes to the neuroprotection or repair in various neurological disease models. However, it should be noted that there are still few articles focusing on the impact of repetitive magnetic stimulation on non-neuronal cells and most studies did not perform in-depth analyses of the effects, emphasizing the need for more studies in this field.

15.
Neural Regen Res ; 19(1): 6-15, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37488837

RESUMO

Adult neurogenesis, the process of creating new neurons, involves the coordinated division, migration, and differentiation of neural stem cells. This process is restricted to neurogenic niches located in two distinct areas of the brain: the subgranular zone of the dentate gyrus of the hippocampus and the subventricular zone of the lateral ventricle, where new neurons are generated and then migrate to the olfactory bulb. Neurogenesis has been thought to occur only during the embryonic and early postnatal stages and to decline with age due to a continuous depletion of neural stem cells. Interestingly, recent years have seen tremendous progress in our understanding of adult brain neurogenesis, bridging the knowledge gap between embryonic and adult neurogenesis. Here, we discuss the current status of adult brain neurogenesis in light of what we know about neural stem cells. In this notion, we talk about the importance of intracellular signaling molecules in mobilizing endogenous neural stem cell proliferation. Based on the current understanding, we can declare that these molecules play a role in targeting neurogenesis in the mature brain. However, to achieve this goal, we need to avoid the undesired proliferation of neural stem cells by controlling the necessary checkpoints, which can lead to tumorigenesis and prove to be a curse instead of a blessing or hope.

16.
Neural Regen Res ; 19(1): 16-21, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37488838

RESUMO

Type-B monoamine oxidase inhibitors, encompassing selegiline, rasagiline, and safinamide, are available to treat Parkinson's disease. These drugs ameliorate motor symptoms and improve motor fluctuation in the advanced stages of the disease. There is also evidence supporting the benefit of type-B monoamine oxidase inhibitors on non-motor symptoms of Parkinson's disease, such as mood deflection, cognitive impairment, sleep disturbances, and fatigue. Preclinical studies indicate that type-B monoamine oxidase inhibitors hold a strong neuroprotective potential in Parkinson's disease and other neurodegenerative diseases for reducing oxidative stress and stimulating the production and release of neurotrophic factors, particularly glial cell line-derived neurotrophic factor, which support dopaminergic neurons. Besides, safinamide may interfere with neurodegenerative mechanisms, counteracting excessive glutamate overdrive in basal ganglia motor circuit and reducing death from excitotoxicity. Due to the dual mechanism of action, the new generation of type-B monoamine oxidase inhibitors, including safinamide, is gaining interest in other neurological pathologies, and many supporting preclinical studies are now available. The potential fields of application concern epilepsy, Duchenne muscular dystrophy, multiple sclerosis, and above all, ischemic brain injury. The purpose of this review is to investigate the preclinical and clinical pharmacology of selegiline, rasagiline, and safinamide in Parkinson's disease and beyond, focusing on possible future therapeutic applications.

17.
Neural Regen Res ; 19(1): 69-74, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37488846

RESUMO

Lactate, a byproduct of glycolysis, was thought to be a metabolic waste until the discovery of the Warburg effect. Lactate not only functions as a metabolic substrate to provide energy but can also function as a signaling molecule to modulate cellular functions under pathophysiological conditions. The Astrocyte-Neuron Lactate Shuttle has clarified that lactate plays a pivotal role in the central nervous system. Moreover, protein lactylation highlights the novel role of lactate in regulating transcription, cellular functions, and disease development. This review summarizes the recent advances in lactate metabolism and its role in neurodegenerative diseases, thus providing optimal perspectives for future research.

18.
Neural Regen Res ; 19(1): 49-54, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37488843

RESUMO

Traumatic brain injury is a serious and complex neurological condition that affects millions of people worldwide. Despite significant advancements in the field of medicine, effective treatments for traumatic brain injury remain limited. Recently, extracellular vesicles released from mesenchymal stem/stromal cells have emerged as a promising novel therapy for traumatic brain injury. Extracellular vesicles are small membrane-bound vesicles that are naturally released by cells, including those in the brain, and can be engineered to contain therapeutic cargo, such as anti-inflammatory molecules, growth factors, and microRNAs. When administered intravenously, extracellular vesicles can cross the blood-brain barrier and deliver their cargos to the site of injury, where they can be taken up by recipient cells and modulate the inflammatory response, promote neuroregeneration, and improve functional outcomes. In preclinical studies, extracellular vesicle-based therapies have shown promising results in promoting recovery after traumatic brain injury, including reducing neuronal damage, improving cognitive function, and enhancing motor recovery. While further research is needed to establish the safety and efficacy of extracellular vesicle-based therapies in humans, extracellular vesicles represent a promising novel approach for the treatment of traumatic brain injury. In this review, we summarize mesenchymal stem/stromal cell-derived extracellular vesicles as a cell-free therapy for traumatic brain injury via neuroprotection and neurorestoration and brain-derived extracellular vesicles as potential biofluid biomarkers in small and large animal models of traumatic brain injury.

20.
Neural Regen Res ; 19(1): 22-28, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37488839

RESUMO

Spinal cord injury is a serious disease of the central nervous system involving irreversible nerve injury and various organ system injuries. At present, no effective clinical treatment exists. As one of the artificial hibernation techniques, mild hypothermia has preliminarily confirmed its clinical effect on spinal cord injury. However, its technical defects and barriers, along with serious clinical side effects, restrict its clinical application for spinal cord injury. Artificial hibernation is a future-oriented disruptive technology for human life support. It involves endogenous hibernation inducers and hibernation-related central neuromodulation that activate particular neurons, reduce the central constant temperature setting point, disrupt the normal constant body temperature, make the body "adapt" to the external cold environment, and reduce the physiological resistance to cold stimulation. Thus, studying the artificial hibernation mechanism may help develop new treatment strategies more suitable for clinical use than the cooling method of mild hypothermia technology. This review introduces artificial hibernation technologies, including mild hypothermia technology, hibernation inducers, and hibernation-related central neuromodulation technology. It summarizes the relevant research on hypothermia and hibernation for organ and nerve protection. These studies show that artificial hibernation technologies have therapeutic significance on nerve injury after spinal cord injury through inflammatory inhibition, immunosuppression, oxidative defense, and possible central protection. It also promotes the repair and protection of respiratory and digestive, cardiovascular, locomotor, urinary, and endocrine systems. This review provides new insights for the clinical treatment of nerve and multiple organ protection after spinal cord injury thanks to artificial hibernation. At present, artificial hibernation technology is not mature, and research faces various challenges. Nevertheless, the effort is worthwhile for the future development of medicine.

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