Relevance of Biochemical Deep Phenotyping for a Personalised Approach to Parkinson's Disease.

Parkinson's disease (PD) is a multifactorial neurodegenerative disorder characterised by the progressive loss of dopaminergic neurons in the nigrostriatal tract. The identification of disease-modifying therapies is the Holy Grail of PD research, but to date no drug has been approved as such a therapy. A possible reason is the remarkable phenotypic heterogeneity of PD patients, which can generate confusion in the interpretation of results or even mask the efficacy of a therapeutic intervention. This heterogeneity should be taken into account in clinical trials, stratifying patients by their expected response to drugs designed to engage selected molecular targets. In this setting, stratification methods (clinical and genetic) should be supported by biochemical phenotyping of PD patients, in line with the deep phenotyping concept. Collection, from single patients, of a range of biological samples would streamline the generation of these profiles. Several studies have proposed biochemical characterisations of patient cohorts based on analysis of blood, cerebrospinal fluid, urine, stool, saliva and skin biopsy samples, with extracellular vesicles attracting increasing interest as a source of biomarkers. In this review we report and critically discuss major studies that used a biochemical approach to stratify their PD cohorts. The analyte most studied is α-synuclein, while other studies have focused on neurofilament light chain, lysosomal proteins, inflammasome-related proteins, LRRK2 and the urinary proteome. At present, stratification of PD patients, while promising, is still a nascent approach. Deep phenotyping of patients will allow clinical researchers to identify homogeneous subgroups for the investigation of tailored disease-modifying therapies, enhancing the chances of therapeutic success.

Dyskinesia and Parkinson's disease: animal model, drug targets, and agents in preclinical testing.

INTRODUCTION: Parkinson's disease (PD) is the second most common neurodegenerative disease after Alzheimer's disease. PD patients exhibit a classic spectrum of motor symptoms, arising when dopamine neurons in the substantia nigra pars compacta are reduced by 60%. The dopamine precursor L-DOPA represents the most effective therapy for improving PD motor dysfunctions, thus far available. Unfortunately, long-term treatment with L-DOPA is associated with the development of severe side effects, resulting in abnormal involuntary movements termed levodopa-induced dyskinesia (LID). Amantadine is the only drug currently approved for the treatment of LID indicating that LID management is still an unmet need in PD and encouraging the search for novel anti-dyskinetic drugs or the assessment of combined therapies with different molecular targets. AREAS COVERED: This review provides an overview of the main preclinical models used to study LID and of the latest preclinical evidence on experimental and clinically available pharmacological approaches targeting non-dopaminergic systems. EXPERT OPINION: LIDs are supported by complex molecular and neurobiological mechanisms that are still being studied today. This complexity suggests the need of developing personalized pharmacological approach to obtain an effective amelioration of LID condition and improve the quality of life of PD patients.

Are Lysosomes Potential Therapeutic Targets for Parkinson's Disease?

Parkinson´s Disease (PD) is the second most common neurodegenerative disorder, affecting ~2-3% of the population over 65 years old. In addition to progressive degeneration of nigrostriatal neurons, the histopathological feature of PD is the accumulation of misfolded α-synuclein protein in abnormal cytoplasmatic inclusions, known as Lewy Bodies (LBs). Recently, Genome-Wide Association Studies (GWAS) have indicated a clear association of variants within several lysosomal genes with risk for PD. Newly evolving data have been shedding light on the relationship between lysosomal dysfunction and alpha-synuclein aggregation. Defects in lysosomal enzymes could lead to the insufficient clearance of neurotoxic protein materials, possibly leading to selective degeneration of dopaminergic neurons. Specific modulation of lysosomal pathways and their components could be considered a novel opportunity for therapeutic intervention for PD. The purpose of this review is to illustrate lysosomal biology and describe the role of lysosomal dysfunction in PD pathogenesis. Finally, the most promising novel therapeutic approaches designed to modulate lysosomal activity, as a potential disease-modifying treatment for PD will be highlighted.

Array of Metabolites in Italian Hericium erinaceus Mycelium, Primordium, and Sporophore.

Hericium erinaceus is a medicinal mushroom that contains many molecules promising a plethora of therapeutic properties. In this study, the strain H.e.2 (MicUNIPV, University of Pavia, Italy) was isolated from a sporophore collected in Tuscany (Italy). Mycelium, primordium, and wild type and cultivated sporophores were analyzed by HPLC-UV-ESI/MS. Erinacine A in the mycelium and hericenones C and D in the sporophores were quantified by comparison with their standard molecules. For the first time, H. erinaceus primordium was also investigated for the presence of these molecules. Comparing with the literature data, hericenes, molecules structurally similar to hericenones, were present in all our samples. The highest contents of hericenones C and D were detected in cultivated sporophores, compared to the wild type. The comparison of these data with those of another Italian H. erinaceus strain (H.e.1 MicUNIPV) was discussed. The results led us to select H. erinaceus strains more suitable for mycelium production or sporophore cultivation to obtain extracts with a higher content of bioactive compounds. This work provides a further step towards standardizing the procedures in the development of dietary supplements made from mushrooms.

Hericium erinaceus Improves Recognition Memory and Induces Hippocampal and Cerebellar Neurogenesis in Frail Mice during Aging.

Frailty is a geriatric syndrome associated with both locomotor and cognitive decline, implicated in both poor quality of life and negative health outcomes. One central question surrounding frailty is whether phenotypic frailty is associated with the cognitive impairment during aging. Using spontaneous behavioral tests and by studying the dynamic change during aging, we demonstrated that the two form of vulnerability, locomotor and recognition memory decline, develop in parallel and therefore, integration of the motoric and cognitive evaluations are imperative. We developed an integrated frailty index based on both phenotypic and recognition memory performances. Hericium erinaceus (H. erinaceus) is a medicinal mushroom that improves recognition memory in mice. By using HPLC-UV-ESI/MS analyses we obtained standardized amounts of erinacine A and hericenones C and D in H. erinaceus extracts, that were tested in our animal model of physiological aging. Two-month oral supplementation with H. erinaceus reversed the age-decline of recognition memory. Proliferating cell nuclear antigen (PCNA) and doublecortin (DCX) immunohistochemistry in the hippocampus and cerebellum in treated mice supported a positive effect of an H. erinaceus on neurogenesis in frail mice.

Phylogenetic Comparison between Italian and Worldwide Hericium Species (Agaricomycetes).

A broad literature concerns the genus Hericium, mainly regarding the medicinal properties of H. erinaceus. Congeneric species of H. erinaceus have been poorly investigated. We collected basidiomata of H. alpestre, H. coralloides and H. erinaceus in Italy and isolated the corresponding mycelia in pure culture. Analysis of the respective internal transcribed spacer regions confirmed the morphological identification of the strains. Internal transcribed spacer sequences from the Italian strains were phylogenetically compared along with 64 other sequences available from Gen-Bank, the CBS Strain Database, and the European Nucleotide Archive (ENA) for the same Hericium . Geographic origin and host plant species were cross-checked using the above data banks. Bayesian phylogenetic analysis produced a phylogram that permitted good discrimination among Hericium species. It provides an updated phylogeny within the genus Hericium and a better understanding of affinity among the species analyzed. The main Hericium clade includes the following: the H. erinaceus group and the H. alpestre/H. coralloides group, where the two species cluster separately. This study also allowed us to differentiate the H. erinaceus group on a biogeographical basis. The phylogenetic comparison further confirms the importance of a joint morphological-molecular approach to avoid misidentification and to guarantee the quality of strains for further chemical and medicinal characterization.

Dietary Supplementation of Lion's Mane Medicinal Mushroom, Hericium erinaceus (Agaricomycetes), and Spatial Memory in Wild-Type Mice.

Hericium erinaceus is an edible and medicinal mushroom with potential neuroprotective effects. The study of H. erinaceus has attracted considerable attention during the past 10 years, particularly with regard to its potential utility in the treatment of motor dysfunction, Alzheimer disease, and other forms of dementia. We previously determined that oral supplementation with H. erinaceus results in significant improvements in novelty-seeking behavior and novel object recognition in mice. In this study, H. erinaceus was added to the diets of wild-type mice for 2 months, and effects on spatial memory were evaluated by means of a Y maze and an object location task. We found that H. erinaceus increased general locomotor activity but had no effect on spatial memory. Thus, oral supplementation with H. erinaceus yields specific and selective improvements in recognition memory without altering spatial working memory, which supports the hypothesis that recognition memory can be modeled as a dual process. In this model, the perirhinal cortex supports the recognition of individual items as part of a circuit involved in familiarity with an encountered stimulus, whereas the hippocampus supports recollected associations and relationships between stimuli.

Dietary Supplementation of Hericium erinaceus Increases Mossy Fiber-CA3 Hippocampal Neurotransmission and Recognition Memory in Wild-Type Mice.

Hericium erinaceus (Bull.) Pers. is a medicinal mushroom capable of inducing a large number of modulatory effects on human physiology ranging from the strengthening of the immune system to the improvement of cognitive functions. In mice, dietary supplementation with H. erinaceus prevents the impairment of spatial short-term and visual recognition memory in an Alzheimer model. Intriguingly other neurobiological effects have recently been reported like the effect on neurite outgrowth and differentiation in PC12 cells. Until now no investigations have been conducted to assess the impact of this dietary supplementation on brain function in healthy subjects. Therefore, we have faced the problem by considering the effect on cognitive skills and on hippocampal neurotransmission in wild-type mice. In wild-type mice the oral supplementation with H. erinaceus induces, in behaviour test, a significant improvement in the recognition memory and, in hippocampal slices, an increase in spontaneous and evoked excitatory synaptic current in mossy fiber-CA3 synapse. In conclusion, we have produced a series of findings in support of the concept that H. erinaceus induces a boost effect onto neuronal functions also in nonpathological conditions.

Distinct expression patterns of inwardly rectifying potassium currents in developing cerebellar granule cells of the hemispheres and the vermis.

G-protein-coupled inwardly rectifying potassium (GIRK) channels play a crucial role during the migration and maturation of cerebellar granule cells (GCs) in the vermis. In the cerebellar hemispheres, however, only minor effects on the development of GCs are observed in mice with GIRK channel impairment. This regional difference may reflect distinct ontogenetic expression patterns of GIRK channels. Therefore, inwardly rectifying responses in mice were characterized at different stages of development in the vermis and the hemispheres. In the vermis, GCs in the premigratory zone (PMZ) at P7-P15 exhibit GIRK current but not constitutive inwardly rectifying potassium (CIRK) current, and are relatively depolarized at rest. In contrast, premigratory GCs in the hemispheres express only CIRK channels, which accounts for their more hyperpolarized resting membrane potential. Furthermore, the pattern of voltage-dependent inward currents in the PMZ GCs of cerebellar hemispheres is consistent with a more mature stage of development than the corresponding GCs in the vermis, resulting in robust firing properties mediated by sodium channels. Later in development (P21-P22), CIRK current is then observed in the majority of vermis GCs. This developmental pattern, revealed by electrophysiological recordings, was confirmed by immunohistological experiments that showed greater reactivity for GIRK2 in the PMZ of the vermis than in the hemispheres during development (P7-P15). These findings suggest that regional differences in development are responsible for the differential expression of inwardly rectifying potassium channels in the vermis and in the hemispheres.

Improving Training Condition Assessment in Endurance Cyclists: Effects of Ganoderma lucidum and Ophiocordyceps sinensis Dietary Supplementation.

The main reasons for taking daily dietary supplements are to maintain good health, to improve homeostasis, and to create conditions for reducing the risk of disease. Due to growing market demand, the search for effective, nontoxic, natural compounds with antioxidant and ergogenic properties has increasingly become a matter of interest. This paper describes how a specific combination of fungal supplements can help improve the performance of endurance athletes. We report the effects of a brief 3-month trial of two fungal supplements, Ganoderma lucidum and Cordyceps sinensis (3 capsules of O. sinensis and 2 capsules of G. lucidum per day), in 7 healthy male volunteers, aged between 30 and 40 years, who are all amateur cyclists that participate in "Gran Fondo" cycling races. This trial investigated the effects of fungal supplements on the level of physical fitness of the athletes by monitoring and comparing the following biomarkers just before and after physical exertion: the testosterone/cortisol ratio in the saliva and oxidative stress (DPPH free radical scavenging activity). A decrease of more than 30% in the testosterone/cortisol ratio after race compared to before race was considered as a risk factor for nonfunctional overreaching (NFO) or the overtraining syndrome (OTS). The results show that, after 3 months of supplementation, the testosterone/cortisol ratio changed in a statistically significant manner, thereby protecting the athletes from NFO and OTS. Antioxidant activity was measured by quantifying the scavenging ability of the human serum on the synthetic free radical DPPH. After 3 months of fungal supplementation, the data demonstrate an increased scavenger capacity of free radicals in the athletes' serum after the race, thereby protecting the athletes from oxidative stress.