INTRODUCTION
Biological ageing, or senescence, is a complex process characterised by progressive functional deterioration and cognitive decline (1). Accumulation of age related changes make individuals more prone to death and disease (2). Understanding these changes is important to understand the complexity of the human lifespan. The Hallmarks of Aging (3), is an article which describes nine factors that contribute to the ageing process. Aggravation or alleviation of these could contribute to the acceleration or delaying of the ageing process (3). One of the primary hallmarks is epigenetics (3); defined as changes in the activity and expression of genes that occur without modification in DNA sequence (4). These changes are performed through transcriptional control. One of the most important mechanisms of epigenetics is DNA methylation, regulated by protein complexes such as methyl-CpG-binding domain (MBD) proteins or HDACs. Histone modification, regulated by enzymes responsible for histone acetylation/deacetylation (including HDACs) and methylation/demethylation (including LSD1) is another …show more content…
The amyloid hypothesis which describes AD pathology involves overproduction of amyloid precursor protein (APP), resulting in increased amyloid beta (Aβ) protein and damage to the blood brain barrier (9). This causes amyloid plaque formation, consequently resulting in cell death due to inflammation, oxidative stress, apoptosis and neuronal cell receptor overactivation (9). The mitochondrial cascade hypothesis of AD pathology explains that age related damage to mitochondrial DNA leads to mitochondrial dysfunction which causes oxidative stress and hence Aβ activation. Mitochondrial DNA mutations are more likely to occur in AD patients
Biological ageing, or senescence, is a complex process characterised by progressive functional deterioration and cognitive decline (1). Accumulation of age related changes make individuals more prone to death and disease (2). Understanding these changes is important to understand the complexity of the human lifespan. The Hallmarks of Aging (3), is an article which describes nine factors that contribute to the ageing process. Aggravation or alleviation of these could contribute to the acceleration or delaying of the ageing process (3). One of the primary hallmarks is epigenetics (3); defined as changes in the activity and expression of genes that occur without modification in DNA sequence (4). These changes are performed through transcriptional control. One of the most important mechanisms of epigenetics is DNA methylation, regulated by protein complexes such as methyl-CpG-binding domain (MBD) proteins or HDACs. Histone modification, regulated by enzymes responsible for histone acetylation/deacetylation (including HDACs) and methylation/demethylation (including LSD1) is another …show more content…
The amyloid hypothesis which describes AD pathology involves overproduction of amyloid precursor protein (APP), resulting in increased amyloid beta (Aβ) protein and damage to the blood brain barrier (9). This causes amyloid plaque formation, consequently resulting in cell death due to inflammation, oxidative stress, apoptosis and neuronal cell receptor overactivation (9). The mitochondrial cascade hypothesis of AD pathology explains that age related damage to mitochondrial DNA leads to mitochondrial dysfunction which causes oxidative stress and hence Aβ activation. Mitochondrial DNA mutations are more likely to occur in AD patients