Intracerebroventricular administration of nerve growth factor induces gliogenesis in sensory ganglia, dorsal root, and within the dorsal root entry zone

A Review of Techniques for Biodelivery of Nerve Growth Factor (NGF) to the Brain in Relation to Alzheimer's Disease

Age-dependent progressive neurodegeneration and associated cognitive dysfunction represent a serious concern worldwide. Currently, dementia accounts for the fifth highest cause of death, among which Alzheimer's disease (AD) represents more than 60% of the cases. AD is associated with progressive cognitive dysfunction which affects daily life of the affected individual and associated family. The cognitive dysfunctions are at least partially due to the degeneration of a specific set of neurons (cholinergic neurons) whose cell bodies are situated in the basal forebrain region (basal forebrain cholinergic neurons, BFCNs) but innervate wide areas of the brain. It has been explicitly shown that the delivery of the neurotrophic protein nerve growth factor (NGF) can rescue BFCNs and restore cognitive dysfunction, making NGF interesting as a potential therapeutic substance for AD. Unfortunately, NGF cannot pass through the blood-brain barrier (BBB) and thus peripheral administration of NGF protein is not viable therapeutically. NGF must be delivered in a way which will allow its brain penetration and availability to the BFCNs to modulate BFCN activity and viability. Over the past few decades, various methodologies have been developed to deliver NGF to the brain tissue. In this chapter, NGF delivery methods are discussed in the context of AD.

Nerve Growth Factor Protects Against Pyrethroid-Induced Endoplasmic Reticulum (ER) Stress in Primary Hippocampal Neurons

Neurotrophins are a family of growth factors crucial for growth and survival of neurons in the developing and adult brain. Reduction in neurotrophin levels is associated with reduced neurogenesis and cognitive deficits in rodents. Recently, we demonstrated that long-term exposure to low levels of the pyrethroid pesticide deltamethrin causes hippocampal endoplasmic reticulum (ER) stress and learning deficits in mice. Here, we found that nerve growth factor (NGF) mRNA and protein were selectively reduced in the hippocampus of deltamethrin-treated mice. To explore potential mechanisms responsible for this observation, we employed mouse primary hippocampal neurons. Exposure of neurons to deltamethrin (1-5 μM) caused ER stress as indicated by increased levels of C/EBP-homologous protein (CHOP) and glucose-regulated protein 78 (GRP78). These changes were accompanied by increased levels of caspase-12, activated caspase-3, and decreased levels of NGF. Inhibition of ER stress with the eukaryotic initiation factor 2 alpha (eIF2α) inhibitor salubrinal abolished deltamethrin-induced activation of caspase-12 and caspase-3, and restored NGF levels. Furthermore, deltamethrin decreased Akt (protein kinase B) phosphorylation, which was significantly prevented by co-treatment with NGF or SC-79 in cells. Collectively, these results demonstrate that the loss of NGF following ER stress may contribute to deltamethrin-induced apoptosis in the hippocampus through the Akt signaling pathway, and that this may provide a plausible mechanism for impaired learning and memory observed following exposure of mice to deltamethrin.

Nanoparticle Therapy Is a Promising Approach in the Management and Prevention of Many Diseases: Does It Help in Curing Alzheimer Disease?

Treatment of brain diseases is always limited by the physiological nature of the highly selective blood-brain barrier (BBB) and the electrostatic charge of the nanoporous extracellular matrix. Nanomedical application provides a promising drug delivery revolution for the treatment of neurodegenerative diseases (NDDs). It depends on improving the pharmacokinetic distribution of drugs through the central nervous system. Nanotechnology offers various forms of nanoparticles, and these nanoparticles have brain-targeted and long-acting properties with minimal systemic adverse effects and motor complications. Gene delivery vehicles and nanocarriers including neurotrophic factors are promising therapeutics for many NDDs, and they can modulate neuronal survival and synaptic connectivity. Neurotrophic factors when integrated with the nanotechnological approaches can pass the BBB merely, representing a significant challenging track. Clinical trials proved that levodopa nanoparticles cause little motor complications which is a considerable drawback in treating Parkinson’s disease with levodopa. Recently, nanotechnology had patented new formulations and achieved various advanced procedures for management, and even prevention, of NDDs. Nanotechnology can be integrated into neuroscience to fight against neurodegenerative diseases. Primary research studies in using nanoparticles to cure Alzheimer disease (AD) are promising but are still in need for more investigations. The present paper aims to review, outline, and summarize various efforts done in the field of using nanoparticles in the management of Alzheimer.

The transplantation of human urine stem cells combined with chondroitinase ABC promotes brain-derived neurotrophic factor and nerve growth factor following spinal cord injury in rats

Cells based on therapies are currently gaining momentum in neural tissue engineering to treat spinal cord injury (SCI). The present study aimed to evaluate the effects of the concomitant use of human urine stem cells (hUSCs) and chondroitinase ABC (ChABC) on functional improvement and to explore the expressions of brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF). The SCI model was induced by a falling heavy object. hUSCs were cultured and transplanted into the impaired spinal cord with ChABC administration. The Basso, Beattie and Bresnahan (BBB) scores were valued, and real time PCR, immunofluorescence and Western blot were used to detect the expression of BDNF and NGF. We found that rats receiving both hUSCs and ChABC treatment demonstrated the best functional recovery. In addition, the mRNA and protein expressions of the BDNF and NGF expressions were found to be effectively higher in the combined treatment group than these in the other groups. In conclusion, hUSCs transplantation combined with ChABC administration promotes motor functional recovery in SCI rats, which may be associated with BDNF and NGF regulation.