Oxidative stress has been linked with a variety of diseases, being involved in the debut and/or progress of several neurodegenerative disorders. This review intends to summarize some of the findings that correlate the overproduction of reactive oxygen species with the pathophysiology of Alzheimer’s disease, Parkinson’s disease, Huntington’s disease, and amyotrophic lateral sclerosis. Oxidative stress was also noted to modify the inflammatory response. Even though oxidative stress and neuroinflammation are two totally different pathological events, they are linked and affect one another. Nonetheless, there are still several mechanisms that need to be understood regarding the onset and the progress of neurodegenerative diseases in order to develop efficient therapies. As antioxidants are a means to alter oxidative stress and slow down the symptoms of these neurodegenerative diseases, the most common antioxidants, enzymatic as well as non-enzymatic, have been mentioned in this paper as therapeutic options for the discussed disorders.

Neurotransmitters are molecules that amplify, transmit, and convert signals in cells, having an essential role in information transmission throughout the nervous system. Hundreds of such chemicals have been discovered in the last century, continuing to be identified and studied concerning their action on brain health. These substances have been observed to influence numerous functions, including emotions, thoughts, memories, learning, and movements. Thus, disturbances in neurotransmitters’ homeostasis started being correlated with a plethora of neurological and neurodegenerative disorders. In this respect, the present paper aims to describe the most important neurotransmitters, broadly classified into canonical (e.g., amino acids, monoamines, acetylcholine, purines, soluble gases, neuropeptides) and noncanonical neurotransmitters (e.g., exosomes, steroids, D-aspartic acid), and explain their link with some of the most relevant neurological conditions. Moreover, a brief overview of the recently developed neurotransmitters’ detection methods is offered, followed by several considerations on the modulation of these substances towards restoring homeostasis.

Angiogenesis is the process through which novel blood vessels are formed from pre-existing ones and it is involved in both physiological and pathological processes of the body. Furthermore, tumor angiogenesis is a crucial factor associated with tumor growth, progression, and metastasis. In this manner, there has been a great interest in the development of anti-angiogenesis strategies that could inhibit tumor vascularization. Conventional approaches comprise the administration of anti-angiogenic drugs that target and block the activity of proangiogenic factors. However, as their efficacy is still a matter of debate, novel strategies have been focusing on combining anti-angiogenic agents with chemotherapy or immunotherapy. Moreover, nanotechnology has also been investigated for the potential of nanomaterials to target and release anti-angiogenic drugs at specific sites. The aim of this paper is to review the mechanisms involved in angiogenesis and tumor vascularization and provide an overview of the recent trends in anti-angiogenic strategies for cancer therapy.

The blood–brain barrier (BBB) has shown to be a significant obstacle to brain medication delivery. The BBB in a healthy brain is a diffusion barrier that prevents most substances from passing from the blood to the brain; only tiny molecules can pass across the BBB. The BBB is disturbed in specific pathological illnesses such as stroke, diabetes, seizures, multiple sclerosis, Parkinson’s disease, and Alzheimer’s disease. The goal of this study is to offer a general overview of current brain medication delivery techniques and associated topics from the last five years. It is anticipated that this review will stimulate readers to look into new ways to deliver medications to the brain. Following an introduction of the construction and function of the BBB in both healthy and pathological conditions, this review revisits certain contested questions, such as whether nanoparticles may cross the BBB on their own and if medications are selectively delivered to the brain by deliberately targeted nanoparticles. Current non-nanoparticle options are also discussed, including drug delivery via the permeable BBB under pathological circumstances and the use of non-invasive approaches to improve brain medication absorption.

The intricate microstructure of the blood-brain barrier (BBB) is responsible for the accurate intrinsic regulation of the central nervous system (CNS), in terms of neuronal pathophysiological phenomena. Any disruption to the BBB can be associated with genetic defects triggering or with local antigenic invasion (either neurotoxic blood-derived metabolites and residues or microbial pathogens). Such events can be further related to systemic inflammatory or immune disorders, which can subsequently initiate several neurodegenerative pathways. Any degenerative process related to the CNS results in progressive and yet incurable impairment of neuronal cells. Since these particular neurons are mostly scanty or incapable of self-repair and regeneration processes, there is tremendous worldwide interest in novel therapeutic strategies for such specific conditions. Alzheimer’s and Parkinson’s diseases (AD and PD, respectively) are conditions found worldwide, being considered the most rampant degenerative pathologies related to CNS. The current therapy of these conditions, including both clinical and experimental approaches, mainly enables symptom management and subsidiary neuronal protection and even less disease regression. Still, a thorough understanding of the BBB pathophysiology and an accurate molecular and sub-molecular management of AD and PD will provide beneficial support for more specific and selective therapy. Since nanotechnology-derived materials and devices proved attractive and efficient platforms for modern biomedicine (including detection, imaging, diagnosis, medication, restoration and regeneration), a particular approach for AD and PD management relies on nanoparticle-based therapy. In this paper we will discuss relevant aspects related to the BBB and its impact on drug-based treatment and emphasize that nanoparticles are suitable and versatile candidates for the development of novel and performance-enhanced nanopharmaceuticals for neurodegenerative conditions therapy.

Although moderate concentrations of reactive oxygen species (ROS) and reactive nitrogen species (RNS) are crucial for various physiological processes within the human body, their overproduction leads to oxidative stress, defined as the imbalance between the production and accumulation of ROS and the ability of the body to neutralize and eliminate them. In the brain, oxidative stress exhibits significant effects, due to its increased metabolical activity and limited cellular regeneration. Thus, oxidative stress is a major factor in the progressive loss of neurons structures and functions, leading to the development of severe neurodegenerative disorders. In this context, recent years have witnessed tremendous advancements in the field of antioxidant therapies, with a special emphasis for neuroprotection. The aim of this paper is to provide an overview of the oxidative stress and antioxidant defense mechanisms and to present the most recent studies on antioxidant therapies for neuroprotection.