Interactions of COMT and ALDH2 Genetic Polymorphisms on Symptoms of Parkinson's Disease

GBA moderates cognitive reserve's effect on cognitive function in patients with Parkinson's disease

BACKGROUND

Cognitive reserve (CR) involves an individual's ability to maintain cognitive vitality over their lifespan. Glucocerebrosidase (GBA) gene mutations contribute to additional effects on cognitive function in Parkinson's disease (PD) patients, but the interplay between GBA mutations and CR remains unclear. We investigated the interactions among CR, GBA, and diseases, aiming to examine whether the CR established at different stages interacts with specific genotypes to affect cognitive function.

METHODS

Three hundred and eighteen participants' CR indicators (i.e., education, occupation, and social function) and comprehensive neuropsychological function (i.e., tests for executive function, attention/working memory, visuospatial function, memory, and language) were evaluated.

RESULTS

We found that CR established in a specific life stage influences the individual's cognitive function, particularly in PD, based on their distinct GBA rs9628662 genotypes. Attention/working memory and memory performance are affected by occupational complexity in midlife in PD patients with the GG genotype (q < 0.0001; q < 0.0001) and healthy adults with the T genotype (q = 0.0440; q < 0.0001). Language is influenced by early education and occupation, and the effects of occupation are also observed in PD patients with the GG genotype (q = 0.0040) and in healthy adults carrying the T genotype (q = 0.0040).

CONCLUSIONS

CR, established at different life stages, can be influenced by the GBA rs9628662 genotype, impacting later-life cognition. Validating genotypes and incorporating genotype information when assessing cognitive reserve effects is crucial and can enhance targeted cognitive training.

Development and validation of the geriatric apathy scale: Examining multi-dimensional apathy profiles in a neurodegenerative population with cultural considerations

BACKGROUND

Apathy is a common motivational deficit in neurodegenerative diseases, but lacks a culturally sensitive tool accounting for ethnic Chinese culture's impact on motivation initiation. This study developed and validated the Geriatric Apathy Scale (GAS), comprehensively incorporating cultural nuances, setting diagnostic cutoffs, and examining apathy's multi-dimensional aspects in a neurodegenerative cohort.

METHODS

The 16-item GAS was developed by considering ethnic Chinese cultural characteristics and conducting a literature review. The study involved 296 participants, comprising 113 with Parkinson's disease (PD), 66 with Alzheimer's disease (AD), and 117 healthy controls (HC). All participants completed the GAS, Apathy Evaluation Scale (AES), Geriatric Depression Scale (GDS-15), Mini-Mental State Examination, and Activities of Daily Living (ADLs).

RESULTS

The GAS showed good internal consistency (r = 0.862) and test-retest reliability (r = 0.767). It correlated moderately with the AES (r = 0.639, p < .001), weakly with GDS-15 (r = 0.166, p < .01), and negatively with ADLs (r = -1.19, p < .05). Clinical diagnosis cutoff scores were identified at 15.5 for PD (sensitivity: 0.789; specificity: 0.693) and 12.5 for AD (sensitivity: 0.821; specificity: 0.632). Noteworthy disparities were observed in the Cognition and Social Motivation dimension, with elevated severity in both PD and AD compared to HC (p < .01). Interestingly, within-group comparisons revealed greater apathy severity in the Cognition and Social Motivation dimension for PD (p < .001) and AD (p = .001) versus Emotional Response and Expression and Spontaneous Behavioral Activation.

CONCLUSIONS

The GAS, a psychometrically validated scale, assesses apathy in neurodegenerative populations, accounting for ethnic Chinese culture's influence. It establishes clinical cutoff points and explores the multi-dimensional nature of apathy.

Current genetic data on depression and anxiety in Parkinson's disease patients

Parkinson's disease (PD) is a common neurodegenerative disorder affecting about 1 % of the population over the age of 60 years. PD is characterized by a wide spectrum of symptomatology including not only motor symptoms but non-motor symptoms, as well. Depression is one of the most common non-motor manifestations, and the most frequent neuropsychiatric comorbidity in PD. Neuropsychiatric symptoms like depression and anxiety may precede the appearance of motor features, highlighting their importance in the early detection of the disease and its strategic management. This review discusses the possible genetic background of the development of these neuropsychiatric symptoms in PD patients analyzing current genetic data associated with this clinical entity.

Genetic Insights into the Molecular Pathophysiology of Depression in Parkinson's Disease

Background and Objectives: Parkinson's disease (PD) is a clinically heterogeneous disorder with poorly understood pathological contributing factors. Depression presents one of the most frequent non-motor PD manifestations, and several genetic polymorphisms have been suggested that could affect the depression risk in PD. Therefore, in this review we have collected recent studies addressing the role of genetic factors in the development of depression in PD, aiming to gain insights into its molecular pathobiology and enable the future development of targeted and effective treatment strategies. Materials and Methods: we have searched PubMed and Scopus databases for peer-reviewed research articles published in English (pre-clinical and clinical studies as well as relevant reviews and meta-analyses) investigating the genetic architecture and pathophysiology of PD depression. Results: in particular, polymorphisms in genes related to the serotoninergic pathway (sodium-dependent serotonin transporter gene, SLC6A4, tryptophan hydrolase-2 gene, TPH2), dopamine metabolism and neurotransmission (dopamine receptor D3 gene, DRD3, aldehyde dehydrogenase 2 gene, ALDH2), neurotrophic factors (brain-derived neurotrophic factor gene, BDNF), endocannabinoid system (cannabinoid receptor gene, CNR1), circadian rhythm (thyrotroph embryonic factor gene, TEF), the sodium-dependent neutral amino acid transporter B(0)AT2 gene, SLC6A15), and PARK16 genetic locus were detected as altering susceptibility to depression among PD patients. However, polymorphisms in the dopamine transporter gene (SLC6A3), monoamine oxidase A (MAOA) and B (MAOB) genes, catechol-O-methyltransferase gene (COMT), CRY1, and CRY2 have not been related to PD depression. Conclusions: the specific mechanisms underlying the potential role of genetic diversity in PD depression are still under investigation, however, there is evidence that they may involve neurotransmitter imbalance, mitochondrial impairment, oxidative stress, and neuroinflammation, as well as the dysregulation of neurotrophic factors and their downstream signaling pathways.

Aldehyde dehydrogenase 2 polymorphism is associated with chemotherapy-related cognitive impairment in patients with breast cancer who receive chemotherapy

BACKGROUND

Chemotherapy-related cognitive impairment (CRCI) is a common but easily overlooked condition that markedly affects the quality of life (QOL) of patients with breast cancer. The rs671 is a common gene polymorphism of aldehyde dehydrogenase 2 (ALDH2) in Asia that is involved in aldehyde metabolism and may be closely related to CRCI. However, no study has yet summarised the association between ALDH2 and CRCI.

METHODS

This study enrolled one hundred and twenty-four patients diagnosed with breast cancer according to the pathology results, genotyped for ALDH2 single-nucleotide polymorphisms (SNP) to explore these. The mini-mental state exam (MMSE), verbal fluency test (VFT), and digit span test (DST) results were compared in these patients before and after chemotherapy (CT).

RESULTS

We found that patients with ALDH2 gene genotypes of rs671_GG, rs886205_GG, rs4648328_CC, and rs4767944_TT polymorphisms were more likely to suffer from cognitive impairment during chemotherapy. A trend toward statistical significance was observed for rs671_GG of DST (z = 2.769, p = 0.006), VFT (t = 4.624, P<0.001); rs886205_GG of DST (z = 3.663, P<0.001); rs4648328_CC of DST (z = 2.850, p = 0.004), VFT (t = 3.477, p = 0.001); and rs4767944_TT of DST (z = 2.967, p = 0.003), VFT (t = 2.776, p = 0.008). The cognitive indicators of these patients significantly decreased after chemotherapy (p < 0.05). The difference in ALDH2 rs671 was most obvious.

CONCLUSION

Our results showed what kinds of ALDH2 genotyped patients that are more likely to develop CRCI. In the future, it may be possible to infer the risk of CRCI by detecting the single-nucleotide locus of ALDH2 that is conducive to strengthening clinical interventions for these patients and improving their QOL. More importantly, this study has important implications for Asian women with breast cancer as ALDH2 rs671 is a common polymorphism in Asians.

Investigating the interaction between neuropsychiatry features and daily activities on social function in patients with Parkinson's disease with mild cognitive impairment

BACKGROUND

Social functioning is crucial for daily living and is an essential indicator of dementia in patients with Parkinson's disease. The pattern of social functioning in patients with Parkinson's disease without dementia (i.e. those who are cognitively intact or have mild cognitive impairment (PD-MCI)) and its determinants are unclear.

AIMS

In exploring the heterogeneity of social functioning among patients with Parkinson's disease-associated dementia, we determined the optimal cut-off score of the Parkinson's Disease Social Functioning Scale (PDSFS) for patients with PD-MCI, and the variables influencing patients' social functioning.

METHOD

A total of 302 participants underwent the Mini-Mental State Examination (MMSE) and PDSFS; 120 patients with Parkinson's disease completed the measurements (MMSE, Activities of Daily Living Scale and Neuropsychiatric Inventory). Group comparisons, receiver operating characteristic curves, Spearman correlation and multiple and hierarchical regression analyses were conducted.

RESULTS

The PD-MCI group scored the lowest on the PDSFS (F = 10.10, P < 0.001). The PDSFS cut-off score was 53 (area under the curve 0.700, sensitivity 0.800, specificity 0.534). The MMSE (β = 0.293, P = 0.002), Activities of Daily Living Scale (β = 0.189, P = 0.028) and Neuropsychiatric Inventory (β = -0.216, P = 0.005) scores predicted the PDSFS score. Further, there was an interaction effect between the Activities of Daily Living Scale and Neuropsychiatric Inventory scores on the PDSFS score (β = 0.305, P < 0.001).

CONCLUSIONS

We determined a PDSFS cut-off score for detecting PD-MCI and found that patients with PD-MCI have social dysfunction. Future research should focus on the effects of neuropsychiatry symptoms and activities of daily living on social functioning, and tailor the intervention programme for patients with Parkinson's disease.

Mild cognitive impairment in patients with Parkinson’s disease: An updated mini-review and future outlook

Mild cognitive impairment (MCI) is one of the common non-motor symptoms in patients with Parkinson’s disease (PD). MCI is the transition stage between normal aging and full-blown dementia and is also a powerful predictor of dementia. Although the concept of MCI has been used to describe some of the PD symptoms for many years, there is a lack of consistent diagnostic criteria. Moreover, because of the diverse patterns of the cognitive functions, each cognitive impairment will have a different progression. In this review, we overviewed the diagnostic criteria for PD-MCI, primarily focused on the heterogeneity of PD-MCI patients’ cognitive function, including various types of cognitive functions and their progression rates. A review of this topic is expected to be beneficial for clinical diagnosis, early intervention, and treatment. In addition, we also discussed the unmet needs and future vision in this field.

Aldehyde Dehydrogenase 2 as a Therapeutic Target in Oxidative Stress-Related Diseases: Post-Translational Modifications Deserve More Attention

Aldehyde dehydrogenase 2 (ALDH2) has both dehydrogenase and esterase activity; its dehydrogenase activity is closely related to the metabolism of aldehydes produced under oxidative stress (OS). In this review, we recapitulate the enzyme activity of ALDH2 in combination with its protein structure, summarize and show the main mechanisms of ALDH2 participating in metabolism of aldehydes in vivo as comprehensively as possible; we also integrate the key regulatory mechanisms of ALDH2 participating in a variety of physiological and pathological processes related to OS, including tissue and organ fibrosis, apoptosis, aging, and nerve injury-related diseases. On this basis, the regulatory effects and application prospects of activators, inhibitors, and protein post-translational modifications (PTMs, such as phosphorylation, acetylation, S-nitrosylation, nitration, ubiquitination, and glycosylation) on ALDH2 are discussed and prospected. Herein, we aimed to lay a foundation for further research into the mechanism of ALDH2 in oxidative stress-related disease and provide a basis for better use of the ALDH2 function in research and the clinic.

Commentary on: Evaluation of spice and herb as phyto-derived selective modulators of human retinaldehyde dehydrogenases using simple in vitro method

It is commonly known that aldehyde dehydrogenases (ALDHs) are a promising therapeutic target in many diseases. Bui et al. - the authors of the paper I am discussing here (Biosci Rep (2021) 41(5): BSR20210491; DOI: https://doi.org/10.1042/BSR20210491) - point that there is a lack of research on the use of spices and herbs as the sources of naturally occurring modulators of ALDH activity. In order to carry out this type of research, the authors prepared ethanolic extracts of 22 spices and herbs. The main objective of the study was to investigate retinaldehyde dehydrogenases (RALDHs), of which retinal is the main substrate and ALDH2, the mitochondrial isoform, having acetaldehyde as the main substrate. The obtained results indicated that the tested extracts exhibited differential regulatory effects on RALDHs/ALDH2 and some of them showed a potential selective inhibition of the activity of RALDHs.

Sources and triggers of oxidative damage in neurodegeneration

Neurodegeneration describes a group of more than 300 neurological diseases, characterised by neuronal loss and intra- or extracellular protein depositions, as key neuropathological features. Multiple factors play role in the pathogenesis of these group of disorders: mitochondrial dysfunction, membrane damage, calcium dyshomeostasis, metallostasis, defect clearance and renewal mechanisms, to name a few. All these factors, without exceptions, have in common the involvement of immensely increased generation of free radicals and occurrence of oxidative stress, and as a result - exhaustion of the scavenging potency of the cellular redox defence mechanisms. Besides genetic predisposition and environmental exposure to toxins, the main risk factor for developing neurodegeneration is age. And although the "Free radical theory of ageing" was declared dead, it is undisputable that accumulation of damage occurs with age, especially in systems that are regulated by free radical messengers and those that oppose oxidative stress, protein oxidation and the accuracy in protein synthesis and degradation machinery has difficulties to be maintained. This brief review provides a comprehensive summary on the main sources of free radical damage, occurring in the setting of neurodegeneration.