scholarly journals The Role of Dietary Antioxidants in the Pathogenesis of Neurodegenerative Diseases and Their Impact on Cerebral Oxidoreductive Balance

Nutrients ◽  
2020 ◽  
Vol 12 (2) ◽  
pp. 435 ◽  
Author(s):  
Anna Winiarska-Mieczan ◽  
Ewa Baranowska-Wójcik ◽  
Małgorzata Kwiecień ◽  
Eugeniusz R. Grela ◽  
Dominik Szwajgier ◽  
...  

Neurodegenerative diseases are progressive diseases of the nervous system that lead to neuron loss or functional disorders. Neurodegenerative diseases require long-term, sometimes life-long pharmacological treatment, which increases the risk of adverse effects and a negative impact of pharmaceuticals on the patients’ general condition. One of the main problems related to the treatment of this type of condition is the limited ability to deliver drugs to the brain due to their poor solubility, low bioavailability, and the effects of the blood-brain barrier. Given the above, one of the main objectives of contemporary scientific research focuses on the prevention of neurodegenerative diseases. As disorders related to the competence of the antioxidative system are a marker in all diseases of this type, the primary prophylactics should entail the use of exogenous antioxidants, particularly ones that can be used over extended periods, regardless of the patient’s age, and that are easily available, e.g., as part of a diet or as diet supplements. The paper analyzes the significance of the oxidoreductive balance in the pathogenesis of neurodegenerative diseases. Based on information published globally in the last 10 years, an analysis is also provided with regard to the impact of exogenous antioxidants on brain functions with respect to the prevention of this type of diseases.

2020 ◽  
Vol 12 ◽  
Author(s):  
Zhengran Yu ◽  
Zemin Ling ◽  
Lin Lu ◽  
Jin Zhao ◽  
Xiang Chen ◽  
...  

Osteoporosis and neurodegenerative diseases are two kinds of common disorders of the elderly, which often co-occur. Previous studies have shown the skeletal and central nervous systems are closely related to pathophysiology. As the main structural scaffold of the body, the bone is also a reservoir for stem cells, a primary lymphoid organ, and an important endocrine organ. It can interact with the brain through various bone-derived cells, mostly the mesenchymal and hematopoietic stem cells (HSCs). The bone marrow is also a place for generating immune cells, which could greatly influence brain functions. Finally, the proteins secreted by bones (osteokines) also play important roles in the growth and function of the brain. This article reviews the latest research studying the impact of bone-derived cells, bone-controlled immune system, and bone-secreted proteins on the brain, and evaluates how these factors are implicated in the progress of neurodegenerative diseases and their potential use in the diagnosis and treatment of these diseases.


Biomolecules ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 1683
Author(s):  
Octavio Silva-García ◽  
Ricarda Cortés-Vieyra ◽  
Francisco N. Mendoza-Ambrosio ◽  
Guillermo Ramírez-Galicia ◽  
Víctor M. Baizabal-Aguirre

The biological activity of the enzyme glycogen synthase kinase-3 (GSK3) is fulfilled by two paralogs named GSK3α and GSK3β, which possess both redundancy and specific functions. The upregulated activity of these proteins is linked to the development of disorders such as neurodegenerative disorders (ND) and cancer. Although various chemical inhibitors of these enzymes restore the brain functions in models of ND such as Alzheimer’s disease (AD), and reduce the proliferation and survival of cancer cells, the particular contribution of each paralog to these effects remains unclear as these molecules downregulate the activity of both paralogs with a similar efficacy. Moreover, given that GSK3 paralogs phosphorylate more than 100 substrates, the simultaneous inhibition of both enzymes has detrimental effects during long-term inhibition. Although the GSK3β kinase function has usually been taken as the global GSK3 activity, in the last few years, a growing interest in the study of GSK3α has emerged because several studies have recognized it as the main GSK3 paralog involved in a variety of diseases. This review summarizes the current biological evidence on the role of GSK3α in AD and various types of cancer. We also provide a discussion on some strategies that may lead to the design of the paralog-specific inhibition of GSK3α.


Author(s):  
Adejoke Onaolapo ◽  
Olakunle Onaolapo

: The possible impact of viral infections on the development or pathogenesis of neurodegenerative disorders remains largely unknown. However, there have been reports associating the influenza virus pandemic and long-term infection with the Japanese encephalitis virus with the development of post-encephalitic Parkinsonism or von Economo encephalitis. In the last one year plus, there has been a worldwide pandemic arising from infection with the novel coronavirus or severe acute respiratory syndrome coronavirus (SARS-CoV)-2 which causes a severe acute respiratory syndrome that has become associated with central nervous system symptoms or complications. Its possible central nervous system involvement is in line with emerging scientific evidence which shows that the human respiratory coronaviruses can enter the brain, infect neural cells, persist in the brain, and cause activation of myelin-reactive T cells. Currently, there is a dearth of scientific information on the acute or possible long-term impact of infection with SARS-CoV-2 on the development of dementias and/or neurodegenerative diseases. This is not unrelated to the fact that the virus is ‘new’, and its effects on humans are still being studied. This narrative review examines extant literature for the impact of corona virus infections on the brain; as it considers the possibility that coronavirus disease 2019 (COVID-19) could increase the risk for the development of neurodegenerative diseases or hasten their progression.


2013 ◽  
Vol 33 (4) ◽  
pp. 550-556 ◽  
Author(s):  
Jordi Duran ◽  
Isabel Saez ◽  
Agnes Gruart ◽  
Joan J Guinovart ◽  
José M Delgado-García

Glycogen is the only carbohydrate reserve of the brain, but its overall contribution to brain functions remains unclear. Although it has traditionally been considered as an emergency energetic reservoir, increasing evidence points to a role of glycogen in the normal activity of the brain. To address this long-standing question, we generated a brain-specific Glycogen Synthase knockout (GYS1Nestin-KO) mouse and studied the functional consequences of the lack of glycogen in the brain under alert behaving conditions. These animals showed a significant deficiency in the acquisition of an associative learning task and in the concomitant activity-dependent changes in hippocampal synaptic strength. Long-term potentiation (LTP) evoked in the hippocampal CA3-CA1 synapse was also decreased in behaving GYS1Nestin-KO mice. These results unequivocally show a key role of brain glycogen in the proper acquisition of new motor and cognitive abilities and in the underlying changes in synaptic strength.


2020 ◽  
Vol 4 (Supplement_1) ◽  
Author(s):  
Neta Gotlieb ◽  
Kathryn E Wilsterman ◽  
Samantha L Finn ◽  
Madison Browne ◽  
Damhee Hu ◽  
...  

Abstract Despite numerous findings detailing the negative impact of stress on female reproductive health, the means by which stress acts on the CNS and periphery to compromise reproductive success remains poorly understood. As a result, the current study sought to clarify the neuroendocrine mechanisms by which stress acts on the brain to deleteriously influence pregnancy outcomes. Reproduction is regulated by the hypothalamo-pituitary-gonadal (HPG) axis, with hypothalamic gonadotropin-releasing hormone (GnRH) neurons representing the final, common pathway of this axis. Cells expressing the inhibitory neuropeptide, RFamide-related peptide-3 (RFRP-3), lie upstream of the GnRH system and are markedly regulated by environmental and psychosocial factors, including stress. In the present study, we asked whether RFRP-3 neurons mediate the effects of stress on pregnancy outcomes through the regulation of prolactin secretion, as prolactin is critical for pregnancy maintenance. More specifically, because specialized hypothalamic dopaminergic neurons, namely tubero-infundibular dopaminergic (TIDA) neurons, are major regulators of prolactin secretion, we hypothesized that RFRP-3 neurons directly target TIDA cells to negatively influence fetal development. To test this possibility, we subjected pregnant mice to chronic restraint stress for the first half of pregnancy and performed a broad screen of hypothalamic neuroendocrine function compared to non-stressed controls. Stressed mice exhibited elevated baseline concentrations of corticosterone that remained high at least 6 days after the final exposure to stress. Whereas progesterone concentrations were reduced by stress early in pregnancy, stressed mice recovered typical progesterone secretion during late gestation. These early, stressful experiences resulted in persistent developmental delays, reduced embryo weight, and abnormal placental histology. Significantly, a small percentage of TIDA cells receive close contacts from RFRP-3 axons, providing a mechanism for the control of prolactin secretion by stress. However, contrary to expectation, the percentage of TIDA neurons receiving input from RFRP-3 cells was not impacted by stress. Together, these findings identify a potential pathway of control for the impact of stress on neuroendocrine factors critical to pregnancy success, although further work using more sensitive approaches is needed to examine the putative role of RFRP-3 on stress-induced pregnancy outcomes.


2018 ◽  
Vol 1 (1) ◽  
pp. 7-12
Author(s):  
Margaret M. Mweshi ◽  
◽  
Hastings K. Shula ◽  
Loveness A. Nkhata ◽  
Brian Chiluba ◽  
...  

Background: Stroke is a global health problem and one of the major causes of death, disability and impairment among adults worldwide. Post-stroke outcomes vary widely, between and within world regions depending on a range of factors including demographic profile, stroke type, severity and immediate and long-term post stroke care. It has been reported that early initiation of rehabilitation following stroke promotes better long-term outcomes than delayed rehabilitation, although this has been disputed by some researchers in the AVERT (A very early rehabilitation trial) study. Purpose of Review: To evaluate the best time to start stroke rehabilitation with good outcomes Results of the Review: There is limited evidence to show that later rehabilitation is better than early rehabilitation. It also remains unclear whether early mobilization is more effective than mobilization at a later stage, due to insufficient statistical power of the studies that have examined this practice because clinicians around the world are practicing this model to this day. Furthermore, some trial limitations of the AVERT study in line with the uncertainty of the external validity of the results, make generalizability something to be concerned about. Conclusion: The best time to start stroke rehabilitation is as soon as the patient is clinically stable i.e; as early as possible. The results of the poor outcomes of the AVERT study in providing evidence of the impact of early stroke rehabilitation, should not be interpreted as proof of the ineffectiveness of early physical rehabilitation. Every stroke is different from one person to another because the impact of the damage to the brain is associated with the different functions of several parts of the brain making generalizability quite difficult. Therefore, in the absence of provision of high quality evidence, clinicians like physiotherapists should base their decisions on clinical experience, individual circumstances and patient preferences as appropriate. It is extremely important to develop evidence-based practice protocols that can guide clinical practice on the best time to start stroke rehabilitation and also enhancing plasticity and reducing the negative impact of stroke through pharmacotherapy, especially for


2004 ◽  
pp. 406-412
Author(s):  
Paul Okunieff ◽  
Michael C. Schell ◽  
Russell Ruo ◽  
E. Ronald Hale ◽  
Walter G. O'Dell ◽  
...  

✓ The role of radiosurgery in the treatment of patients with advanced-stage metastatic disease is currently under debate. Previous randomized studies have not consistently supported the use of radiosurgery to treat patients with numbers of brain metastases. In negative-results studies, however, intracranial tumor control was high but extracranial disease progressed; thus, patient survival was not greatly affected, although neurocognitive function was generally maintained until death. Because the future promises improved systemic (extracranial) therapy, the successful control of brain disease is that much more crucial. Thus, for selected patients with multiple metastases to the brain who remain in good neurological condition, aggressive lesion-targeting radiosurgery should be very useful. Although a major limitation to success of this therapy is the lack of control of extracranial disease in most patients, it is clear that well-designed, aggressive treatment substantially decreases the progression of brain metastases and also improves neurocognitive survival. The authors present the management and a methodology for rational treatment of a patient with breast cancer who has harbored 24 brain metastases during a 3-year period.


Author(s):  
Giuseppe Lisco ◽  
Vito A. Giagulli ◽  
Giovanni De Pergola ◽  
Anna De Tullio ◽  
Edoardo Guastamacchia ◽  
...  

Background: The novel pandemic of Coronavirus disease 2019 (COVID-19) has becoming a public health issue since March 2020 considering that more than 30 million people were found to be infected worldwide. Particularly, recent evidences suggested that men may be considered as at higher risk of poor prognosis or death once the infection occurred and concerns surfaced in regard of the risk of a possible testicular injury due to SARS-CoV-2 infection. Results: Several data support the existence of a bivalent role of testosterone (T) in driving poor prognosis in patients with COVID-19. On one hand, this is attributable to the fact that T may facilitate SARS-CoV-2 entry in human cells by means of an enhanced expression of transmembrane serine-protease 2 (TMPRSS2) and angiotensin-converting enzyme 2 (ACE2). At the same time, younger man with normal testicular function compared to women of similar age are prone to develop a blunted immune response against SARS-CoV-2, being exposed to less viral clearance and more viral shedding and systemic spread of the disease. Conversely, low levels of serum T observed in hypogonadal men predispose them to a greater background systemic inflammation, cardiovascular and metabolic diseases, and immune system dysfunction, hence driving harmful consequences once SARS-CoV-2 infection occurred. Finally, SARS-CoV-2, as a systemic disease, may also affect testicles with possible concerns for current and future testicular efficiency. Preliminary data suggested that SARS-CoV-2 genome is not normally found in gonads and gametes, therefore sex transmission could be excluded as a possible way to spread the COVID-19. Conclusion: Most data support a role of T as a bivalent risk factor for poor prognosis (high/normal in younger; lower in elderly) in COVID-19. However, the impact of medical treatment aimed to modify T homeostasis for improving the prognosis of affected patients is unknown in this clinical setting. In addition, testicular damage may be a harmful consequence of the infection even in case it occurred asymptomatically but no long-term evidences are currently available to confirm and quantify this phenomenon. Different authors excluded the presence of SARS-CoV-2 in sperm and oocytes, thus limiting worries about both a potential sexual and gamete-to-embryos transmission of COVID-19. Despite these evidence, long-term and well-designed studies are needed to clarify these issues.


2021 ◽  
Vol 13 (8) ◽  
pp. 4513
Author(s):  
Summaira Malik ◽  
Muhammad Taqi ◽  
José Moleiro Martins ◽  
Mário Nuno Mata ◽  
João Manuel Pereira ◽  
...  

The success of a construction project is a widely discussed topic, even today, and there exists a difference of opinion. The impact of communication and conflict on project success is an important, but least addressed, issue in literature, especially in the case of underdeveloped countries. Miscommunication and conflict not only hinder the success of a project but also may lead to conflicts. The focus of this paper was to examine the impact of communication on project success with the mediating role of conflict. By using SPSS, demographics, descriptive statistics and correlation were determined. Smart PLS version 3.0 was used for confirmatory factor analysis (CFA), internal accuracy and validity estimates, hypothesis checking and mediation testing. The results showed that formal communication has a negative impact on the success of a construction project, resulting in conflicts among project team members, whereas informal communication and communication willingness have a positive impact on project success because people tend to know each other, and trust is developed. Task, process and relationship conflicts were used as mediating variables. It was found that task conflict effects the relations positively because project team members suggest different ways to do a certain task, and, hence, project success is achieved. On the contrary, process conflict and relationship conflict have a negative impact on communication and project success. Both of these conflicts lead to miscommunication, and project success is compromised. Hence, it is the responsibility of the project manager to enhance communication among project team members and to reduce the detrimental effects of process and relationship conflict on project success.


2021 ◽  
Vol 10 (1) ◽  
Author(s):  
David Western ◽  
Victor N. Mose ◽  
David Maitumo ◽  
Caroline Mburu

Abstract Background Studies of the African savannas have used national parks to test ecological theories of natural ecosystems, including equilibrium, non-equilibrium, complex adaptive systems, and the role of top-down and bottom-up physical and biotic forces. Most such studies have excluded the impact of pastoralists in shaping grassland ecosystems and, over the last half century, the growing human impact on the world’s rangelands. The mounting human impact calls for selecting indicators and integrated monitoring methods able to track ecosystem changes and the role of natural and human agencies. Our study draws on five decades of monitoring the Amboseli landscape in southern Kenya to document the declining role of natural agencies in shaping plant ecology with rising human impact. Results We show that plant diversity and productivity have declined, biomass turnover has increased in response to a downsizing of mean plant size, and that ecological resilience has declined with the rising probability of extreme shortfalls in pasture production. The signature of rainfall and physical agencies in driving ecosystem properties has decreased sharply with growing human impact. We compare the Amboseli findings to the long-term studies of Kruger and Serengeti national parks to show that the human influence, whether by design or default, is increasingly shaping the ecology of savanna ecosystems. We look at the findings in the larger perspective of human impact on African grasslands and the world rangelands, in general, and discuss the implications for ecosystem theory and conservation policy and management. Conclusions The Amboseli study shows the value of using long-term integrated ecological monitoring to track the spatial and temporal changes in the species composition, structure, and function of rangeland ecosystems and the role of natural and human agencies in the process of change. The study echoes the widespread changes underway across African savannas and world’s rangelands, concluding that some level of ecosystem management is needed to prevent land degradation and the erosion of ecological function, services, and resilience. Despite the weak application of ecological theory to conservation management, a plant trait-based approach is shown to be useful in explaining the macroecological changes underway.


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