Exercise-Induced Cognitive Plasticity, Implications for Mild Cognitive Impairment and Alzheimer’s Disease

Abstract

Lifestyle factors such as intellectual stimulation, cognitive and social engagement, nutrition, and various types of exercise appear to reduce the risk for common age-associated disorders such as Alzheimer’s disease (AD) and vascular dementia. In fact, many studies have suggested that promoting physical activity can have a protective effect against cognitive deterioration later in life. Slowing or a deterioration of walking speed is associated with a poor performance in tests assessing psychomotor speed and verbal fluency in elderly individuals. Fitness training influences a wide range of cognitive processes, and the largest positive impact observed is for executive (a.k.a. frontal lobe) functions. Studies show that exercise improves additional cognitive functions such as tasks mediated by the hippocampus, and result in major changes in plasticity in the hippocampus. Interestingly, this exercise-induced plasticity is also pronounced in APOE ε4 carriers who express a risk factor for late-onset AD that may modulate the effect of treatments. Based on AD staging by Braak and Braak (1991) and Braak et al. (1993) we propose that the effects of exercise occur in two temporo-spatial continua of events. The “inward” continuum from isocortex (neocortex) to entorhinal cortex/hippocampus for amyloidosis and a reciprocal “outward” continuum for neurofibrillary alterations. The exercise-induced hypertrophy of the hippocampus at the core of these continua is evaluated in terms of potential for prevention to stave off neuronal degeneration. Exercise-induced production of growth factors such as the brain-derived neurotrophic factor (BDNF) has been shown to enhance neurogenesis and to play a key role in positive cognitive effects. Insulin-like growth factor (IGF-1) may mediate the exercise-induced response to exercise on BDNF, neurogenesis, and cognitive performance. It is also postulated to regulate brain amyloid β (Aβ) levels by increased clearance via the choroid plexus. Growth factors, specifically fibroblast growth factor and IGF-1 receptors and/or their downstream signaling pathways may interact with the Klotho gene which functions as an aging suppressor gene. Neurons may not be the only cells affected by exercise. Glia (astrocytes and microglia), neurovascular units and the Fourth Element may also be affected in a differential fashion by the AD process. Analyses of these factors, as suggested by the multi-dimensional matrix approach, are needed to improve our understanding of this complex multi-factorial process, which is increasingly relevant to conquering the escalating and intersecting world-wide epidemics of dementia, diabetes, and sarcopenia that threaten the global healthcare system. Physical activity and interventions aimed at enhancing and/or mimicking the effects of exercise are likely to play a significant role in mitigating these epidemics, together with the embryonic efforts to develop cognitive rehabilitation for neurodegenerative disorders.

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“…BDNF is a key protein in the regulation for the sustainability of growth, for the life of neurons and important activity of synaptic transmission. On physical exercises, BDNF can stimulate neurogenesis in the form of the formation of new neurons [22,24,46]. The study result ( Table- Not many explanations of the relation of CRP and AD [33].…”

“…The increase of serum BDNF, increase of hippocampal and the medial part of the temporal lobe volumes and the improvement of memory disorders are found after physical exercises [22,23,24].…”

Hubungan lama terdiagnosa diabetes dan kadar glukosa darah dengan fungsi kognitif penderita diabetes tipe 2 di Jawa Timur

“…19 Terdapat juga penelitian lain yang menyatakan bahwa faktor gaya hidup, adanya stimulasi stimulasi intelektual terkait kognitif, status sosial dan adanya aktifitas fisik dapat menurunkan resiko gangguan seperti Alzheimer's disease dan demensia vaskular. 20 Pengukuran kadar glukosa darah puasa (GDP) sebagai salah satu hasil dari tes glukosa darah puasa yang digunakan untuk menguji efektivitas obat atau pengaruh makanan yang memberikan hasil berbeda pada orang yang sudah didiagnosa sebagai penderita diabetes . Konsensus Perkeni menyatakan GDP pada pasien yang sudah menderita DM dikatakan terkendali jika nilai GDP sebesar 80-126 mg/dL.…”

Recent advances in nutrition, genes and brain health

“…Considerable evidence links physical activity and optimal energy intake with improved mood and cognitive function, whereas both underweight and obesity are associated with impaired cognitive performance (1,2,(46)(47)(48) . Studies on the psychotherapy eye movement desensitisation and reprocessing raise the possibility that outdoor activity such as walking may be especially beneficial for mental health and well-being.…”