Stem cell therapies in neurology: the good, the bad and the unknown

Recent Updates on the Development of Therapeutics for the Targeted Treatment of Alzheimer's Disease

Alzheimer's disease (AD) is a complicated, multifaceted, irreversible, and incurable neurotoxic old age illness. Although NMDA (N-methyl D-aspartate)-receptor antagonists, cholinesterase repressors, and their pairings have been approved for the treatment, they are useful for short symptomatic relief. Researchers throughout the globe have been constantly working to uncover the therapy of Alzheimer's disease as new candidates must be determined, and newer treatment medicines must be developed. The aim of this review is to address recent advances in medication research along with new Alzheimer's disease therapy for diverse targets. Information was gathered utilizing a variety of internet resources as well as websites, such as ALZFORUM (alzforum.org) and clinicaltrials.gov. In contrast to other domains, the proposed medicines target amyloids (secretases, A42 generation, neuroinflammation, amyloid precipitation, and immunization), tau proteins (tau phosphorylation/aggregation and immunotherapy), and amyloid deposition. Despite tremendous advancement in our understanding of the underlying pathophysiology of Alzheimer's disease, the FDA (Food and Drug Administration) only approved aducanumab for diagnosis and treatment in 2003. Hence, novel treatment tactics are needed to find and develop therapeutic medicines to combat Alzheimer's disease.

Recent advances on drug development and emerging therapeutic agents for Alzheimer's disease

Alzheimer's disease (AD) is a neurodegenerative old age disease that is complex, multifactorial, unalterable, and progressive in nature. The currently approved therapy includes cholinesterase inhibitors, NMDA-receptor antagonists and their combination therapy provides only temporary symptomatic relief. Sincere efforts have been made by the researchers globally to identify new targets, discover, and develop novel therapeutic agents for the treatment of AD. This brief review article is intended to cover the recent advances in drug development and emerging therapeutic agents for AD acting at different targets. The article is compiled using various scientific online databases and by referring to clinicaltrials.gov and ALZFORUM (alzforum.org) websites. The upcoming therapies act on one or more targets including amyloids (secretases, Aβ₄₂ production, amyloid deposition, and immunotherapy), tau proteins (tau phosphorylation/aggregation and immunotherapy) and neuroinflammation in addition to other miscellaneous targets. Despite the tremendous improvement in our understanding of the underlying pathophysiology of AD, only aducanumab was approved by FDA for the treatment of AD in 18 years i.e., since 2003. Hence, it is concluded that novel therapeutic strategies are required to discover and develop therapeutic agents to fight against the century old AD.

Therapeutic Potential of Repeated Intravenous Transplantation of Human Adipose-Derived Stem Cells in Subchronic MPTP-Induced Parkinson's Disease Mouse Model

Parkinson’s disease (PD) is the second most common neurodegenerative disease, which is clinically and pathologically characterized by motor dysfunction and the loss of dopaminergic neurons in the substantia nigra, respectively. PD treatment with stem cells has long been studied by researchers; however, no adequate treatment strategy has been established. The results of studies so far have suggested that stem cell transplantation can be an effective treatment for PD. However, PD is a progressively deteriorating neurodegenerative disease that requires long-term treatment, and this has been insufficiently studied. Thus, we aimed to investigate the therapeutic potential of human adipose-derived stem cells (hASC) for repeated vein transplantation over long-term in an animal model of PD. In 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced PD model mice, hASCs were administered on the tail vein six times at two-week intervals. After the last injection of hASCs, motor function significantly improved. The number of dopaminergic neurons present in the nigrostriatal pathway was recovered using hASC transplantation. Moreover, the administration of hASC restored altered dopamine transporter expression and increased neurotrophic factors, such as brain-derived neurotrophic factor (BDNF) and glial cell-derived neurotrophic factor (GDNF), in the striatum. Overall, this study suggests that repeated intravenous transplantation of hASC may exert therapeutic effects on PD by restoring BDNF and GDNF expressions, protecting dopaminergic neurons, and maintaining the nigrostriatal pathway.

Crowdfunding for stem cell-based interventions to treat neurologic diseases and injuries

Objective

To characterize the marketplace for direct-to-consumer (DTC) unproven stem cell-based interventions (SCBI) for neurologic diseases and injuries using crowdfunding data.

Methods

Search terms were developed from previous empirical studies of DTC businesses and the International Classification of Diseases–11 for neurologic diseases and used to query GoFundMe's internal search engine. Campaigns initiated November 2017–2018 and seeking SCBI for neurologic diseases and injuries (n = 1,030) were reviewed to identify the number of donors, number of Facebook shares, recipient location, funding pledged, funding requested, underlying neurologic condition, treatment location, and treatment facility name.

Results

A total of 1,030 crowdfunding campaigns for SCBI for neurologic diseases and injuries requested $33,449,979 and received $5,057,069 from 38,713 donors. The most common neurologic condition identified was multiple sclerosis (MS) (n = 404, 35.5%). Of campaigns naming specific destination facilities (n = 392), the most common clinical settings identified were the Stem Cell Institute in Panama City, Panama (n = 91, 23.2%), StemGenex in San Diego, California (n = 44, 11.2%), and Clinica Ruiz in Puebla, Mexico (n = 36, 9.2%).

Conclusions

MS dominated the total number of crowdfunding campaigns. Most campaigns were linked to individuals from regions geographically proximal to destination facilities advertising SCBI for particular neurologic diseases. Most of the clinical destinations were located in comparatively high-income countries such as the United States, Mexico, and Panama. These findings provide considerable insight into the DTC marketplace for SCBI. Analysis of crowdfunding campaigns can be used to develop more targeted patient education initiatives and health policies related to domestic and international travel for unproven SCBI.