The Blood-Brain Barrier and Brain Drug Delivery

The present report encompasses a thorough review of drug delivery to the brain with a particular focus on using drug carriers such as liposomes and nanoparticles. Challenges in brain drug delivery arise from the presence of one of the strictest barriers in vivo—the blood-brain barrier (BBB). This barrier exists at the level of endothelial cells of brain vasculature and its role is to maintain brain homeostasis. To better understand the principles of brain drug delivery, relevant knowledge of the blood-brain barrier anatomy and physiology is briefly reviewed. Several approaches to overcome the BBB have been reviewed including the use of carrier systems. In addition, strategies to enhance brain drug delivery by specific brain targeting are discussed.

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Liposomes: Novel Drug Delivery Approach for Targeting Parkinson’s Disease

Current Pharmaceutical Design ◽

10.2174/1381612826666200128145124 ◽

2020 ◽

Vol 26 (37) ◽

pp. 4721-4737 ◽

Cited By ~ 4

Author(s):

Bhumika Kumar ◽

Mukesh Pandey ◽

Faheem H. Pottoo ◽

Faizana Fayaz ◽

Anjali Sharma ◽

...

Keyword(s):

Parkinson’S Disease ◽

Drug Delivery ◽

Parkinson's Disease ◽

Side Effects ◽

Blood Brain Barrier ◽

Brain Barrier ◽

Brain Targeting ◽

Neural Cells ◽

Blood Brain ◽

The Brain

Parkinson’s disease is one of the most severe progressive neurodegenerative disorders, having a mortifying effect on the health of millions of people around the globe. The neural cells producing dopamine in the substantia nigra of the brain die out. This leads to symptoms like hypokinesia, rigidity, bradykinesia, and rest tremor. Parkinsonism cannot be cured, but the symptoms can be reduced with the intervention of medicinal drugs, surgical treatments, and physical therapies. Delivering drugs to the brain for treating Parkinson’s disease is very challenging. The blood-brain barrier acts as a highly selective semi-permeable barrier, which refrains the drug from reaching the brain. Conventional drug delivery systems used for Parkinson’s disease do not readily cross the blood barrier and further lead to several side-effects. Recent advancements in drug delivery technologies have facilitated drug delivery to the brain without flooding the bloodstream and by directly targeting the neurons. In the era of Nanotherapeutics, liposomes are an efficient drug delivery option for brain targeting. Liposomes facilitate the passage of drugs across the blood-brain barrier, enhances the efficacy of the drugs, and minimize the side effects related to it. The review aims at providing a broad updated view of the liposomes, which can be used for targeting Parkinson’s disease.

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Brain Drug Delivery: Overcoming the Blood-brain Barrier to Treat Tauopathies

Current Pharmaceutical Design ◽

10.2174/1381612826666200316130128 ◽

2020 ◽

Vol 26 (13) ◽

pp. 1448-1465 ◽

Cited By ~ 1

Author(s):

Jozef Hanes ◽

Eva Dobakova ◽

Petra Majerova

Keyword(s):

Drug Delivery ◽

Blood Brain Barrier ◽

Neurodegenerative Disorders ◽

Brain Barrier ◽

Neuronal Function ◽

Brain Drug Delivery ◽

Naturally Occurring ◽

Blood Brain ◽

Traditional Approaches ◽

The Brain

Tauopathies are neurodegenerative disorders characterized by the deposition of abnormal tau protein in the brain. The application of potentially effective therapeutics for their successful treatment is hampered by the presence of a naturally occurring brain protection layer called the blood-brain barrier (BBB). BBB represents one of the biggest challenges in the development of therapeutics for central nervous system (CNS) disorders, where sufficient BBB penetration is inevitable. BBB is a heavily restricting barrier regulating the movement of molecules, ions, and cells between the blood and the CNS to secure proper neuronal function and protect the CNS from dangerous substances and processes. Yet, these natural functions possessed by BBB represent a great hurdle for brain drug delivery. This review is concentrated on summarizing the available methods and approaches for effective therapeutics’ delivery through the BBB to treat neurodegenerative disorders with a focus on tauopathies. It describes the traditional approaches but also new nanotechnology strategies emerging with advanced medical techniques. Their limitations and benefits are discussed.

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Pharmacological Modulation of Blood–Brain Barrier Permeability by Kinin Analogs in Normal and Pathologic Conditions

Pharmaceuticals ◽

10.3390/ph13100279 ◽

2020 ◽

Vol 13 (10) ◽

pp. 279

Author(s):

Dina Sikpa ◽

Lisa Whittingstall ◽

Martin Savard ◽

Réjean Lebel ◽

Jérôme Côté ◽

...

Keyword(s):

Blood Brain Barrier ◽

Brain Barrier ◽

Brain Drug Delivery ◽

Blood Brain ◽

Brain Barrier Permeability ◽

Radiation Induced ◽

B2 Receptors ◽

Peptide Agonist ◽

The Brain

The blood–brain barrier (BBB) is a major obstacle to the development of effective diagnostics and therapeutics for brain cancers and other central nervous system diseases. Peptide agonist analogs of kinin B1 and B2 receptors, acting as BBB permeabilizers, have been utilized to overcome this barrier. The purpose of the study was to provide new insights for the potential utility of kinin analogs as brain drug delivery adjuvants. In vivo imaging studies were conducted in various animal models (primary/secondary brain cancers, late radiation-induced brain injury) to quantify BBB permeability in response to kinin agonist administrations. Results showed that kinin B1 (B1R) and B2 receptors (B2R) agonists increase the BBB penetration of chemotherapeutic doxorubicin to glioma sites, with additive effects when applied in combination. B2R agonist also enabled extravasation of high-molecular-weight fluorescent dextrans (155 kDa and 2 MDa) in brains of normal mice. Moreover, a systemic single dose of B2R agonist did not increase the incidence of metastatic brain tumors originating from circulating breast cancer cells. Lastly, B2R agonist promoted the selective delivery of co-injected diagnostic MRI agent Magnevist in irradiated brain areas, depicting increased vascular B2R expression. Altogether, our findings suggest additional evidence for using kinin analogs to facilitate specific access of drugs to the brain.

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Gemini quaternary ammonium-incorporated biodegradable multiblock polyurethane micelles for brain drug delivery

RSC Advances ◽

10.1039/c4ra09908g ◽

2015 ◽

Vol 5 (8) ◽

pp. 6160-6171 ◽

Cited By ~ 5

Author(s):

Rui-Chao Liang ◽

Fang Fang ◽

Yan-Chao Wang ◽

Ni-Jia Song ◽

Jie-Hua Li ◽

...

Keyword(s):

Drug Delivery ◽

Blood Brain Barrier ◽

Quaternary Ammonium ◽

Drug Accumulation ◽

Brain Barrier ◽

Brain Drug Delivery ◽

Blood Brain

Gemini quaternary ammonium (GQA) incorporated biodegradable multiblock polyurethane (BMPUs) micelles could transport drug across blood–brain barrier and improve brain drug accumulation.

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An overview of nanomedicines for neuron targeting

Nanomedicine ◽

10.2217/nnm-2020-0088 ◽

2020 ◽

Vol 15 (16) ◽

pp. 1617-1636 ◽

Cited By ~ 2

Author(s):

Jesus Garcia-Chica ◽

West Kristian D Paraiso ◽

Shihori Tanabe ◽

Dolors Serra ◽

Laura Herrero ◽

...

Keyword(s):

Drug Delivery ◽

Blood Brain Barrier ◽

Neuronal Cells ◽

Brain Barrier ◽

Brain Targeting ◽

Brain Cells ◽

Medical Treatments ◽

Blood Brain

Medical treatments of neuron-related disorders are limited due to the difficulty of targeting brain cells. Major drawbacks are the presence of the blood–brain barrier and the lack of specificity of the drugs for the diseased cells. Nanomedicine-based approaches provide promising opportunities for overcoming these limitations. Although many previous reviews are focused on brain targeting with nanomedicines in general, none of those are concerned explicitly on the neurons, while targeting neuronal cells in central nervous diseases is now one of the biggest challenges in nanomedicine and neuroscience. We review the most relevant advances in nanomedicine design and strategies for neuronal drug delivery that might successfully bridge the gap between laboratory and bedside treatment in neurology.

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