**4. Neurodegeneration with Brain Iron Accumulation (NBIA)**

The latest molecular studies revealed the existence of inherited neurodegenerative disorders, termed "neurodegeneration with brain iron accumulation" (NBIA), owing to genetic faults associated with iron metabolism. NBIA is a heterogeneous set of disorders that comprises "Pantothenate Kinase-Associated Neurodegeneration" (PKAN), infantile neuroaxonal defect, and neuroferritinopathy. Together, these disorders share similarities in extrapyramidal neurodegeneration and focal Fe accumulation, frequently in the basal ganglia and further brain regions including the thalamus, SN, cerebellar dentate nucleus and red nucleus. Symptoms comprise disablement in movement and cognition. NBIA consists of a series of disorders, a few caused by a mutation in a well-distinguished metalloprotein.

Along with iron accumulation, lipid peroxidation and mitochondrial damage are involved in both NBIA and ferroptosis, signifying the role of ferroptosis in the development of neurodegenerative diseases.

The general neurodegenerative diseases following TBI (Traumatic Brain Injury) resemble Parkinson's disease (PD) and Alzheimer's disease (AD) too share identical characteristics with ferroptosis, such as overload iron and lipid peroxidation.

Unique with iron excess syndromes, aceruloplasminemia (iron accumulation in the brain and other organs) involves together systemic and brain iron metabolism. A noticeable build-up of iron in the affected parenchymal tissues, namely the liver, pancreas, thyroid, and heart, the outcome in cardiac failure and hypothyroidism. The systemic tissues with access to iron are the reason for disrupted tissue iron release, followed by incorporation into circulating transferrin.

#### **5. Neurological disorders**

There are numerous distinguished neurological disorders, and a number of them are common, but many are rare. They may be evaluated by neurological assessment, studied and treated by the expertise of neuropsychology. Neurological disorders can be classified according to the primary affected area because the primary cause is most important and the wide division is between the central nervous system and peripheral nervous system disorders. Neurological disorders can influence the whole neurological pathway or a neuron alone. Even a little trouble with a neuron's structural pathways can consequence in dysfunction.

There are numerous mechanisms of pathogenesis involved in the progress of neurodegenerative disorders. Internal and external stressors can cause activation of neuroglial cells which involves the disturbance of normal nervous functions and triggers the process of apoptosis in the neuronal cells. A small portion of neurodegenerative diseases are due to the mutation of disease-related genes, but the majority of them are sporadic where environmental issues and ageing plays a predominant role. Disturbance of cellular function from ageing- stimulates the accumulation of neuronal stressors resulting in cell death. Though, there is somewhat little neuronal loss in normal ageing, while cell death is a general characteristic of neurodegenerative diseases.

In the homeostatic regulation of physiological and pathological functions, redox balance plays an important role. When surplus free radicals cannot be eradicated, the accumulation stimulates and leads to "oxidative stress". The reactive oxygen species (ROS) accumulation can cause damage to mitochondrial DNA, agitating the reliability of the energy cycle, which is necessary for neurological growth and function.

Neuronal tissue inflammation happens due to the accumulation of ROS, which encourages the synthesis of cytokines and other inflammatory mediators by triggering the inflammation pathway.

*Neurodegeneracy DOI: http://dx.doi.org/10.5772/intechopen.109597*

Antioxidant therapy represents an assuring possibility for the treatment of neurological diseases. Even though the difficulty and inconsistency of redox biology have mostly avoided the analysis of the mechanisms of and therapeutic approaches for neurological disease.

The lack of early diagnosis and cure for neurodegenerative diseases is always to be a huge confront for society.
