Stereotaxic implantation of autologous adrenal medulla into caudate nucleus in four patients with parkinsonism. One-year follow-up

Autologous mesenchymal stem cell therapy for progressive supranuclear palsy: translation into a phase I controlled, randomized clinical study

Background

Progressive Supranuclear Palsy (PSP) is a sporadic and progressive neurodegenerative disease which belongs to the family of tauopathies and involves both cortical and subcortical structures. No effective therapy is to date available.

Methods/design

Autologous bone marrow (BM) mesenchymal stem cells (MSC) from patients affected by different type of parkinsonisms have shown their ability to improve the dopaminergic function in preclinical and clinical models. It is also possible to isolate and expand MSC from the BM of PSP patients with the same proliferation rate and immuphenotypic profile as MSC from healthy donors. BM MSC can be efficiently delivered to the affected brain regions of PSP patients where they can exert their beneficial effects through different mechanisms including the secretion of neurotrophic factors.

Here we propose a randomized, placebo-controlled, double-blind phase I clinical trial in patients affected by PSP with MSC delivered via intra-arterial injection.

Discussion

To our knowledge, this is the first clinical trial to be applied in a no-option parkinsonism that aims to test the safety and to exploit the properties of autologous mesenchymal stem cells in reducing disease progression. The study has been designed to test the safety of this “first-in-man” approach and to preliminarily explore its efficacy by excluding the placebo effect.

Trial registration

NCT01824121

Melanocortin control of energy balance: evidence from rodent models

Regulation of energy balance is extremely complex, and involves multiple systems of hormones, neurotransmitters, receptors, and intracellular signals. As data have accumulated over the last two decades, the CNS melanocortin system is now identified as a prominent integrative network of energy balance controls in the mammalian brain. Here, we will review findings from rat and mouse models, which have provided an important framework in which to study melanocortin function. Perhaps most importantly, this review attempts for the first time to summarize recent advances in our understanding of the intracellular signaling pathways thought to mediate the action of melanocortin neurons and peptides in control of longterm energy balance. Special attention will be paid to the roles of MC4R/MC3R, as well as downstream neurotransmitters within forebrain and hindbrain structures that illustrate the distributed control of melanocortin signaling in energy balance. In addition, distinctions and controversy between rodent species will be discussed.

Cell-based therapeutic approaches for Parkinson's disease: progress and perspectives

Motor dysfunctions in Parkinson's disease are believed to be primarily due to the degeneration of dopaminergic neurons located in the substantia nigra pars compacta. Because a single-type cell population is depleted, Parkinson's disease is considered a primary target for cell replacement-based therapeutic strategies. Extensive studies have confirmed transplantation of donor neurons could be beneficial, yet identifying an alternative cell source is clearly essential. Human embryonic stem cells (hESCs) have been proposed as a renewable source of dopaminergic neurons for transplantation in Parkinson's disease; other potential sources could include neural stem cells (hNSCs) and adult mesenchymal stem cells (hMSCs). However, numerous difficulties avert practical application of stem cell-based therapeutic approaches for the treatment of Parkinson's disease. Among the latter, ethical, safety (including xeno- and tumor formation-associated risks) and technical issues stand out. This review aims to provide a balanced and updated outlook on various issues associated with stem cells in regard to their potential in the treatment of Parkinson's disease. Essential features of the individual stem cell subtypes, principles of available differentiation protocols, transplantation, and safety issues are discussed extensively.

Orphan neurones and amine excess: the functional neuropathology of Parkinsonism and neuropsychiatric disease

The aetiology and treatment of Parkinsonism is currently conceptualised within a dopamine (DA) deficiency-repletion framework. Loss of striatal DA is thought to cause motor impairment of which tremor, bradykinaesia and rigidity are prominent features. Repletion of deficient DA should at least minimise parkinsonian signs and symptoms. In Section 2, based on extensive pre-clinical and clinical findings, the instability of this approach to Parkinsonism is scrutinised as the existing negative findings challenging the DA deficiency hypothesis are reviewed and reinterpreted. In Section 3 it is suggested that Parkinsonism is due to a DA excess far from the striatum in the area of the posterior lateral hypothalamus (PLH) and the substantia nigra (SN). This unique area, around the diencephalon/mesencephalon border (DCMCB), is packed with many ascending and descending fibres which undergo functional transformation during degeneration, collectively labelled 'orphan neurones'. These malformed cells remain functional resulting in pathological release of transmitter and perpetual neurotoxicity. Orphan neurone formation is commonly observed in the PLH of animals and in man exhibiting Parkinsonism. The mechanism by which orphan neurones impair motor function is analogous to that seen in the diseased human heart. From this perspective, to conceptualise orphan neurones at the DCMCB as 'Time bombs in the brain' is neither fanciful nor unrealistic [E.M. Stricker, M.J. Zigmond, Comments on effects of nigro-striatal dopamine lesions, Appetite 5 (1984) 266-267] as the DA excess phenomenon demands a different therapeutic approach for the management of Parkinsonism. In Section 4 the focus is on this novel concept of treatment strategies by concentrating on non-invasive, pharmacological and surgical modification of functional orphan neurones as they affect adjacent systems. The Orphan neurone/DA excess hypothesis permits a more comprehensive and defendable interpretation of the interrelationship between Parkinsonism and schizophrenia and other related disorders.

Low frequency of alpha-synuclein mutations in familial Parkinson's disease

A mutation in exon 4 of the alpha-synuclein (NACP) gene has been reported to explain the chromosome 4 linkage to autosomal dominant Parkinson's disease. We developed primers and methods for exonic sequencing of this gene and sequenced the entire coding region of the gene in 6 families with autosomal dominant disease and in 2 cases of lytico and bodig from Guam. In addition, we have sequenced exon 4 of this gene in 5 cases of familial disease and have screened for the specific mutation (A53T) in a 40 cases of idiopathic Parkinson's disease, 3 cases of multisystem atrophy, and 15 cases of Lewy body dementia. We have found no genetic variation in the gene. We discuss these findings with respect to both the epidemiology of Parkinson's disease and the possibility that NACP is not the chromosome 4 locus for disease.

Parkinson's disease, trophic factors, and adrenal medullary chromaffin cell grafting: basic and clinical studies

Neural transplantation is one of the promising approaches for the treatment of Parkinson's disease. Although the strategy of using adrenal medulla as donor tissue, rather than fetal nigra tissue, started as an alternative method, recent experimental studies demonstrated the efficacy of adrenal medulla grafting as a neurotrophic source. Many methods to increase the survival of grafted chromaffin cells have been developed, some of which have already been applied clinically with encouraging results. This review summarizes the advancements of adrenal medulla grafting in basic and clinical studies. Special attention is focused on the relationship with neurotrophic factors and how we can enhance the survival of grafted chromaffin cells.

Two-year follow-up study of a patient with Parkinson's disease and severe motor fluctuations treated by co-grafts of adrenal medulla and peripheral nerve into bilateral caudate nuclei: case report

We performed co-grafts of adrenal medulla and peripheral nerve into the bilateral caudate nuclei of a 43-year-old patient with advanced Parkinson's disease who showed severe daily motor fluctuations before surgery. There were no postoperative complications, and a 2-year follow-up result is presented. The patient showed a gradual and significant amelioration of the parkinsonian symptoms starting 2 weeks after transplantation. The alleviation of akinesia during "off" periods was the most apparent clinical improvement and continued for 2 years after surgery. The dosage of L-dopa/benserazide was significantly reduced after surgery compared with that before surgery. The results indicate that co-grafts of adrenal medulla with peripheral nerve may be useful for the treatment of Parkinson's disease in the long term.

Cerebral transplantation for Parkinson's disease: current progress and future prospects

Cerebral transplantation has received considerable attention from both the medical community and lay press as a potential treatment for Parkinson's disease. Animal models have demonstrated feasibility, although the experience in subhuman primates was very limited when the first human trials were initiated in the mid-1980s. The dramatic success reported for adrenal-to-brain transplantation in some initial trials could not be consistently replicated by other centers. Occasionally, however, patients benefited. Failure of the adrenal medullary graft to survive may have been a major factor in the poor outcomes. Recently, several US and European centers reported substantial clinical improvement after fetal dopaminergic mesencephalon was grafted into the striatum of patients with Parkinson's disease. Although many outcomes were impressive, in some cases the improvement was marginal; in no case was the condition completely reversed, and all but one patient still required levodopa therapy. Before this technique can be considered for routine use, further refinement is necessary, and many technical issues must be addressed. Certain animal studies have suggested that transplantation-related improvement may be derived from graft neurotrophic factors rather than from secretion of dopamine into the dopamine-depleted brain of patients with Parkinson's disease. Preliminary investigations in animals indicate that several other tissues, besides fetal mesencephalon, may also prove appropriate for grafting. Ultimately, advances in molecular biology may allow either transplantation of genetically engineered cells or direct modification of existing brain cells by transfection with viral vectors. The favorable preliminary experience with cerebral transplantation in patients with Parkinson's disease has resulted in the consideration of this strategy for other neurologic disorders.

The biology and behaviour of intracerebral adrenal transplants in animals and man

The catecholamine containing chromaffin cells of the adrenal medulla have recently been employed as intracerebral grafts in man and animals with lesions of the nigrostriatal dopaminergic system. This review outlines the basic biology of the chromaffin cell with reference to its efficacy as a source of dopamine in the grafted state. This is followed by an evaluation of the use of these grafts in experimentally lesioned animals and in patients with Parkinson's disease.