10 weeks low intensity treadmill exercise intervention ameliorates motor deficits and sustains muscle mass via decreasing oxidative damage and increasing mitochondria function in a rat model of Parkinson's disease

AIMS

Parkinson's disease (PD) is characterized by loss of dopamine neurons in the brain, which leads to motor dysfunction; excessive inflammation induces neuronal death. This study aimed to determine the most effective exercise modality to improve motor dysfunction in PD by comparing three different exercise regimens (low-intensity treadmill, high-intensity treadmill, and swimming).

MATERIALS AND METHODS

The rat model for PD was established through stereotaxic surgery, inducing unilateral 6-OHDA (6-hydroxydopamine) lesions. The low-intensity treadmill regimen exerted better protective effects on neurological and motor functions in a rat model of unilateral 6-OHDA-induced PD compared to high-intensity treadmill and swimming. The most suitable exercise regimen and the optimal duration of daily exercise (15 or 30 min) on motor activity and oxidative stress parameters were evaluated.

KEY FINDINGS

Comparison of 15 and 30 min low-intensity treadmill regimens (10 m/min) revealed 30 min daily exercise was the optimal duration and had more favorable impacts on neurological and motor function. Furthermore, we assessed the neuroprotective effects of exercising for 15 and 30 min per day for either four or ten weeks; 30 min of daily exercise for ten weeks improved mitochondrial function, the antioxidant defense system, neurotrophic factors, and muscle mass, and thereby provided protection against dopaminergic neuron loss, and motor dysfunction in rats with 6-OHDA-induced PD.

SIGNIFICANCE

30 min of daily low-intensity treadmill exercise over 10 weeks resulted in heightened mitochondrial function in both muscle and brain tissues, therefore, yielded a neuroprotective effect against the loss of dopaminergic neurons and motor dysfunction in PD rats.

Impaired performance of rapid grip in people with Parkinson's disease and motor segmentation

Bradykinesia, or slow movement, is a defining symptom of Parkinson's disease (PD), but the underlying neuromechanical deficits that lead to this slowness remain unclear. People with PD often have impaired rates of motor output accompanied by disruptions in neuromuscular excitation, causing abnormal, segmented, force-time curves. Previous investigations using single-joint models indicate that agonist electromyogram (EMG) silent periods cause motor segmentation. It is unknown whether motor segmentation is evident in more anatomically complex and ecologically important tasks, such as handgrip tasks. Aim 1 was to determine how handgrip rates of force change compare between people with PD and healthy young and older adults. Aim 2 was to determine whether motor segmentation is present in handgrip force and EMG measures in people with PD. Subjects performed rapid isometric handgrip pulses to 20-60% of their maximal voluntary contraction force while EMG was collected from the grip flexors and extensors. Dependent variables included the time to 90% peak force, the peak rate of force development, the duration above 90% of peak force, the number of segments in the force-time curve, the number of EMG bursts, time to relaxation from 90% of peak force, and the peak rate of force relaxation. People with PD had longer durations and lower rates of force change than young and older adults. Six of 22 people with PD had motor segmentation. People with PD had more EMG bursts compared to healthy adults and the number of EMG bursts covaried with the number of segments. Thus, control of rapid movement in Parkinson's disease can be studied using isometric handgrip. People with PD have impaired rate control compared to healthy adults and motor segmentation can be studied in handgrip.

No Evidence of Sensory Neuropathy in a Traditional Mouse Model of Idiopathic Parkinson's Disease

Parkinson's disease (PD) is the second-most common neurodegenerative disorder worldwide and is diagnosed based on motor impairments. Non-motor symptoms are also well-recognised in this disorder, and peripheral neuropathy is a frequent but poorly appreciated non-motor sign. Studying how central and peripheral sensory systems are affected can contribute to the development of targeted therapies and deepen our understanding of the pathophysiology of PD. Although the cause of sporadic PD is unknown, chronic exposure to the pesticide rotenone in humans increases the risk of developing the disease. Here, we aimed to investigate whether peripheral neuropathy is present in a traditional model of PD. Mice receiving intrastriatal rotenone showed greatly reduced dopamine terminals in the striatum and a reduction in tyrosine hydroxylase-positive neurons in the Substantia nigra pars compacta and developed progressive motor impairments in hindlimb stepping and rotarod but no change in spontaneous activity. Interestingly, repeated testing using gold-standard protocols showed no change in gut motility, a well-known non-motor symptom of PD. Importantly, we did not observe any change in heat, cold, or touch sensitivity, again based upon repeated testing with well-validated protocols that were statistically well powered. Therefore, this traditional model fails to replicate PD, and our data again reiterate the importance of the periphery to the disorder.

Analysis of handgrip strength, pulling force using the upper limbs, and ground reaction forces in the task of boarding a bus between healthy elderly individuals and those with Parkinson's disease

INTRODUCTION

Elderly individuals with neurodegenerative diseases, such as Parkinson's disease (PD), may experience difficulties when performing functional tasks.

OBJECTIVE

To analyze the handgrip strength, pulling force, and ground reaction forces (GRF) of individuals with and without PD when boarding a bus while performing both simple (ST) and dual tasks (DT).

METHOD

This case-control study addressed 31 individuals with PD (GPD) and 30 healthy individuals (GHI). Assessments were performed in ST and DT situations using a bus model (prototype). Handgrip strength and pulling force were measured in both upper limbs using a dynamometer, and GRF was measured using a force platform. The GPD's and GHI's performances were compared in both ST and DT, and the individuals were classified as fallers according to the Falls Efficacy Scale.

RESULTS

In the inter-group comparison, the GPD presented significantly lower maximum force using their right hand, in handgrip strength (30.43 vs. 36.62, P = .022), and pulling force (10.77 vs 12.81, P = .037). The left hand's pulling force proved to be the most demanding for the GPD, during ST (6.35 vs. 4.76, P = .006) and DT (6.32 vs 4.74, P = .008). The GPD also took longer to perform ST (6.14 vs. 4.67, P < .001) and DT (6.08 vs. 4.81, P = .002). Additionally, the GPD was more afraid of falling compared to the GHI (34.74 vs. 24.77, P < .001).

CONCLUSION

Boarding a bus is a complex task for individuals with PD because they present lower maximum strength in the upper limbs and more significant functional expenditure than their healthy counterparts.

Association of grip strength and walking pace with the risk of incident Parkinson's disease: a prospective cohort study of 422,531 participants

BACKGROUND

Muscle weakness is a prominent feature of Parkinson's disease, but whether the occurrence of this deficit in healthy adults is associated with subsequent PD diagnosis remains unclear.

OBJECTIVE

This study sought to examine the relationship between muscle strength, represented by grip strength and walking pace, and the risk of incident PD.

METHODS

A total of 422,531 participants from the UK biobank were included in this study. Longitudinal associations of grip strength and walking pace with the risk of incident PD were investigated by Cox proportional hazard models adjusting for several well-established risk factors. Subgroup and sensitivity analyses were also conducted for further validation.

RESULTS

After a median follow-up of 9.23 years, 2,118 (0.5%) individuals developed incident PD. For per 5 kg increment of absolute grip strength, there was a significant 10.2% reduction in the risk of incident PD (HR = 0.898, 95% CI [0.872-0.924], P < 0.001). Similarly, per 0.05 kg/kg increment of relative grip strength was related to a 9.2% reduced risk of incident PD (HR = 0.908, 95% CI [0.887-0.929], P < 0.001). Notably, the associations remained consistent when grip strength was calculated as quintiles. Moreover, participants with a slower walking pace demonstrated an elevated risk of incident PD (HR = 1.231, 95%CI [1.075-1.409], P = 0.003). Subgroup and sensitivity analyses further validated the robustness of the observed associations.

CONCLUSION

Our findings showed a negative association of grip strength and walking pace with the risk of incident PD independent of important confounding factors. These results hold potential implications for the early screening of people at high-risk of PD.

Biomarkers of Physical and Mental Health for Prediction of Parkinson's Disease: A Population-Based Study from 15 European Countries

OBJECTIVES

Early diagnosis of Parkinson's disease (PD) is critical for optimal treatment. However, the predictive potential of physical and mental health in PD is poorly characterized.

METHODS

We evaluated the potential of multiple demographic, physical, and mental factors in predicting the future onset of PD in older adults aged 50 years or older from 15 European countries. Individual study participants were followed over four waves of the Survey of Health, Ageing, and Retirement in Europe (SHARE) from 2013-2020.

RESULTS

Of 57,980 study participants, 442 developed PD during the study period. We identified male sex and advancing age from the sixth decade of life onward as significant predictors of future PD. Among physical factors, a low handgrip strength (HGS; men <27 kg, women <16 kg), being bothered by frailty, and recent falls were significantly associated with future PD. Among mental factors, a higher depression (Euro-D depression score >6) emerged as an independent predictor of future PD. Finally, the presence of hypertension or Alzheimer's disease (AD) increases the risk of future PD.

CONCLUSIONS

Altogether, male sex, advancing age, low HGS, frailty, depression, hypertension, and AD were identified as critical risk factors for future PD. Our results may be useful in the early identification and treatment of populations at risk for PD.

Silencing Parkinson's risk allele Rit2 sex-specifically compromises motor function and dopamine neuron viability

Parkinson's disease (PD) is the second most prevalent neurodegenerative disease and arises from dopamine (DA) neuron death selectively in the substantia nigra pars compacta (SNc). Rit2 is a reported PD risk allele, and recent single cell transcriptomic studies identified a major RIT2 cluster in PD DA neurons, potentially linking Rit2 expression loss to a PD patient cohort. However, it is still unknown whether Rit2 loss itself impacts DA neuron function and/or viability. Here we report that conditional Rit2 silencing in mouse DA neurons drove motor dysfunction that occurred earlier in males than females and was rescued at early stages by either inhibiting the DA transporter (DAT) or with L-DOPA treatment. Motor dysfunction was accompanied by decreased DA release, striatal DA content, phenotypic DAergic markers, DA neurons, and DAergic terminals, with increased pSer129-alpha synuclein and pSer935-LRRK2 expression. These results provide clear evidence that Rit2 loss is causal for SNc cell death and motor dysfunction, and reveal key sex-specific differences in the response to Rit2 loss.

Association of handgrip strength and walking pace with incident Parkinson's disease

BACKGROUND

We aimed to quantify the association of handgrip strength and self-reported walking pace with incident Parkinson's disease (PD) in the general population.

METHODS

A total of 419 572 participants (54.1% females, mean age: 56.1 years [SD, 8.2]) without prior PD were included from UK Biobank. Handgrip strength was assessed by dynamometer. Walking pace was self-reported as slow, average or brisk. The study outcome was incident PD, determined by self-report data, hospital admission records or death records.

RESULTS

The mean handgrip strength was 23.5 (SD, 6.3) and 39.6 (SD, 8.9) kg for females and males, respectively. A total of 33 645 (8.0%), 221 682 (52.8%) and 164 245 (39.2%) participants reported slow, average and brisk walking pace, respectively. Over a median follow-up duration of 12.5 years, 2152 participants developed incident PD. When handgrip strength was assessed as sex-specific tertiles, compared with those in the third tertile, the adjusted hazard ratios (HRs) (95% confidence interval [CI]) of incident PD for participants in the second and first tertiles were 1.23 (1.09-1.39) and 1.60 (1.42-1.79), respectively. Compared with brisk walking pace, average (HR, 1.33; 95% CI: 1.20-1.47) or slow (HR, 1.84; 95% CI: 1.57-2.15) walking pace was associated with a higher risk of incident PD. A lower grip strength (Tertiles 1 and 2) and an average/slow walking pace accounted for 23.8% and 19.9% of PD cases, respectively. When handgrip strength and walking pace were considered together, the highest risk of incident PD was observed in participants with both lowest handgrip strength and slow walking pace (HR, 2.89; 95% CI: 2.30-3.64). Genetic risks of PD did not significantly modify the relation of handgrip strength (P for interaction = 0.371) or walking pace (P for interaction = 0.082) with new-onset PD.

CONCLUSIONS

Low handgrip strength and slow walking pace were significantly associated with a higher risk of incident PD, regardless of the individuals' genetic risk profile.

Involvement of A13 dopaminergic neurons in prehensile movements but not reward in the rat

Tyrosine hydroxylase (TH)-containing neurons of the dopamine (DA) cell group A13 are well positioned to impact known DA-related functions as their descending projections innervate target regions that regulate vigilance, sensory integration, and motor execution. Despite this connectivity, little is known regarding the functionality of A13-DA circuits. Using TH-specific loss-of-function methodology and techniques to monitor population activity in transgenic rats in vivo, we investigated the contribution of A13-DA neurons in reward and movement-related actions. Our work demonstrates a role for A13-DA neurons in grasping and handling of objects but not reward. A13-DA neurons responded strongly when animals grab and manipulate food items, whereas their inactivation or degeneration prevented animals from successfully doing so-a deficit partially attributed to a reduction in grip strength. By contrast, there was no relation between A13-DA activity and food-seeking behavior when animals were tested on a reward-based task that did not include a reaching/grasping response. Motivation for food was unaffected, as goal-directed behavior for food items was in general intact following A13 neuronal inactivation/degeneration. An anatomical investigation confirmed that A13-DA neurons project to the superior colliculus (SC) and also demonstrated a novel A13-DA projection to the reticular formation (RF). These results establish a functional role for A13-DA neurons in prehensile actions that are uncoupled from the motivational factors that contribute to the initiation of forelimb movements and help position A13-DA circuits into the functional framework regarding centrally located DA populations and their ability to coordinate movement.

Rit2 silencing in dopamine neurons drives a Parkinsonian phenotype

Parkinson's disease (PD) is the second most prevalent neurodegenerative disease and arises from dopamine (DA) neuron death selectively in the substantia nigra pars compacta (SNc). Rit2 is a reported PD risk allele, and recent single cell transcriptomic studies identified a major RIT2 cluster in PD DA neurons, potentially linking Rit2 expression loss to a PD patient cohort. However, it is still unknown whether Rit2 loss itself is causative for PD or PD-like symptoms. Here we report that conditional Rit2 silencing in mouse DA neurons drove motor dysfunction that occurred earlier in males than females and was rescued at early stages by either inhibiting the DA transporter (DAT) or with L-DOPA treatment. Motor dysfunction was accompanied by decreased DA release, striatal DA content, phenotypic DAergic markers, DA neurons, and DAergic terminals, with increased pSer129-alpha synuclein and pSer935-LRRK2 expression. These results provide the first evidence that Rit2 loss is causal for SNc cell death and a PD-like phenotype, and reveal key sex-specific differences in the response to Rit2 loss.

Is Handgrip Strength Associated With Parkinson's Disease? Longitudinal Study of 71 702 Older Adults

BACKGROUND

To date, no study has longitudinally assessed the dose-response association between handgrip strength and incidence of Parkinson's Disease (PD).

OBJECTIVES

to investigate the longitudinal association between handgrip strength and the development of PD within a representative European population of older adults.

METHODS

Individuals aged 50 years and older from 27 European countries and Israel participated. We retrieved data from the Survey of Health, Ageing and Retirement in Europe waves 1, 2, 4, 5, 6, 7, and 8. Handgrip strength was measured using a hand dynamometer and participants reported whether they had a medical PD diagnosis. Time-varying exposure and covariates were modeled using both Cox regression and restricted cubic splines.

RESULTS

A total of 71 702 participants (mean age 65.2 years) were followed over a median period of 5.0 years. Among them, 314 participants developed PD. In the fully adjusted model, we observed a higher risk (hazard ratio [HR]: 2.50; 95% CI:1.92-3.32) of PD for participants with lower handgrip strength (third 1) and a lower risk of PD for participants in the second third (HR: 1.41; 95% CI: 1.06-1.87). In dose-response analyses, men showed lower risk of PD from 27 kg (HR:0.94; 95% CI: 0.91-0.97) to 59 kg (HR:0.10; 95% CI: 0.04-0.22), whereas women showed significant reductions from 24 kg (HR:0.68; 95% CI: 0.46-0.99) to 38 kg (HR:0.44; 95% CI: 0.22-0.88).

CONCLUSIONS

Handgrip strength ought to be incorporated as one of the measures in the prognostic toolbox for the screening of older adults who are possibly at risk of developing PD.

Cervical proprioception in Parkinson's disease and its correlation with manual dexterity function

OBJECTIVE

Cervical proprioception plays a crucial role in posture and movement control. This study aimed to determine the relationships of cervical proprioception, cervical muscle strength and endurance with manual dexterity and hand strength in individuals with idiopathic Parkinson's disease (PD).

METHODS

Twenty individuals with PD (mean age: 63.9 years) and 20 healthy individuals as a control group (mean age: 61.9 years) were recruited. Cervical joint position error (JPE), static endurance of neck muscles, activation of deep cervical flexor muscles (Craniocervical Flexion Test, CCFT), manual dexterity (Purdue Pegboard Test, PPT), cognitive and motor tasks of the PPT, finger tapping test (FTT), pinch strength, and grip strength were assessed.

RESULTS

Cervical JPE was significantly higher in individuals with PD than in controls (p < 0.05). The strength and endurance of the cervical muscles were significantly decreased in individuals with PD (p < 0.05). Cervical JPE measurements were negatively correlated with PPT, cognitive and motor tasks of the PPT in individuals with PD (all p < 0.05). The endurance of cervical flexor muscles was negatively correlated with PPT and cognitive PPT scores in the PD group (p < 0.05). In addition, a significant positive correlation was found between cervical flexor endurance and hand strength in the PD group (p < 0.05).

CONCLUSION

Cervical proprioception and the strength and endurance of cervical muscles decrease in individuals with PD compared to healthy individuals. Impairment of cervical proprioception appears to be associated with poorer upper extremity performance. Detailed evaluation of the cervical region in PD may help determine the factors affecting upper extremity function.

The quality of life in individuals with Parkinson's Disease: is it related to functionality and tremor severity? A cross-sectional study

BACKGROUND

Symptoms seen in Parkinson's Disease (PD) affect the quality of life (QoL) of individuals.

OBJECTIVES

This study aimed to examine the relationship of QoL with tremor severity and upper limb functionality in individuals with PD.

METHODS

Parkinson's Disease Quality of Life Questionnaire (PDQ-39) was used to examine the QoL of the participants, electromyography was used to measure the tremor amplitude, Nine-Hole Peg Test (NHPT) was used to evaluate the upper limb functionality and dynamometer was used to evaluate grip and pinch strength. Resting and postural tremor amplitudes were recorded from both sides of the hand and forearm. The relationship between QoL and other parameters was tested with Spearman Correlation Analysis. Mann-Whitney U test was used to compare individuals with and without tremor.

RESULTS

It was obtained that tremor amplitude was significantly related to: activities of daily living (rho = 0.597); emotional well-being (rho = 0.694); stigma (rho = 0.524); social support (rho = 0.595 and 0.559), and communication [rho = 0.532 (right forearm), 0.564 (left forearm), and 0.527 (right hand)] sub-parameters of PDQ-39 (p < .05). The relationship of the grip and pinch strength with the PDQ-39 sub-parameters was significant (p < .05), except for social support and communication. The relationship between NHPT and almost all parameters of PDQ-39 (p < .05), except bodily discomfort and social support, was significant.

CONCLUSION

It was concluded that future studies focusing on QoL could also consider tremor severity and grip strength as well as dexterity in individuals with PD.

The impact of loneliness on quality of life in people with Parkinson's disease: results from the Survey of Health, Ageing and Retirement in Europe

Background

Loneliness is a growing issue for public health in an aging society. However, there is a lack of research on loneliness in people with Parkinson's disease (PwPD).

Methods

We analyzed cross-sectional and longitudinal data from wave 5 (N = 559 PwPD) and 6 (N = 442 PwPD) from the Survey of Health, Ageing and Retirement in Europe (SHARE). Loneliness was assessed using the three-item version of the Revised UCLA Loneliness Scale. Descriptive statistics, group comparisons, multiple linear regressions, and generalized estimating equation analysis were performed to explore loneliness prevalence, its relationship with other factors, and its impact on Quality of Life (QoL) in PwPD.

Results

Depending on the used cut-off, the prevalence of loneliness in PwPD ranged from 24.1 to 53.8%. These prevalences were higher compared to people without PD. Loneliness was mainly linked to decreased functional abilities, weaker grip strength, more symptoms of depression, and country of residence. Loneliness was also associated with current QoL and predicts future QoL in PwPD, highlighting its impact on well-being.

Conclusion

Addressing loneliness could potentially improve QoL for PwPD, making it a modifiable risk factor that clinicians and policy-makers should consider.

Are the digit ratio (2D:4D) and hand grip strength related to Parkinson disease in elderly males?

BACKGROUND

Sex hormones affect the pathogenesis of Parkinson patients and it has been suggested that gender is the most important factor in the development and progression of Parkinson's disease. Studies have shown that the second to fourth digit ratio (2D:4D) is affected by the prenatal testosterone and estrogen levels and can predict predisposition to disease. In addition, decreased muscle strength in people with Parkinson's has been repeatedly reported. Hand grip strength (HGS) is a suitable measure to evaluate the musculoskeletal system among the elderly and it is considered as an indicator of the overall strength of the body. This study aimed at investigating the relationship between Parkinson's disease and HGS and 2D:4D ratio.

METHODS

In this study 117 elderly men with Parkinson disease (mean age of 61.66 ± 11.28 years) and 156 healthy control subjects (mean age of 61.86 ± 6.29 years) participated. After determining the level of disability of Parkinson patients by a neurologist (level of disability in the range of 1-4), anthropometric indices (height, weight, length of the second and fourth fingers) and maximum HGS were measured.

RESULTS

Although 2D:4D ratios (right and left hand) of male patients with Parkinson's disease were higher than those of healthy males, this difference was not statistically significant (P = 0.12, P = 0.40; respectively). Conversely, HGS for the right and left hands of Parkinson patients were significantly lower than those of healthy males (P = 0.02, P = 0.03; respectively). The results showed a significant negative relationship between Parkinson disease and the right and left HGS (R = -0.16, P = 0.005; R = -0.17, P = 0.003; respectively). Parkinson disease had no significant relationship with 2D:4D of the right hand, left hand, mean finger ratio and D_R-L 2D:4D (P > 0.05). The regression results showed that the right and left HGS were not able to predict Parkinson disease (P = 0.25, P = 0.16; respectively).

CONCLUSION

We concluded that HGS was negatively associated with the Parkinson disease, but conversely, 2D:4D may not be a valuable biomarker of elevated risk of Parkinson in elderly males.

Feasibility of a combined intermittent theta-burst stimulation and video game-based dexterity training in Parkinson's disease

BACKGROUND

Persons with Parkinson's disease (PD) often exhibit difficulties with dexterity during the performance of activities of daily living (ADL), inter alia due to dysfunctional supplementary motor area (SMA). Combined intermittent theta-burst stimulation (iTBS) over the SMA followed by video game-based training (VBT) may therefore improve dexterity related ADL. The VBT may induce high flow levels related to high performance during the training. The aim of this study is to evaluate the feasibility of a combined iTBS-VBT intervention in persons with PD.

METHODS

A total of nine persons with PD (mean age 63.3 ± 8.76 years) with self-reported difficulties with dexterity related ADL were included in this pilot iTBS-VBT study. All participants received either iTBS or sham stimulation over the SMA followed by a 45-min VBT, three times a week for a total of three weeks. Feasibility was measured by means of the adherence rate and the system usability (System Usability Scale). Moreover, flow was measured after the last VBT session.

RESULTS

Adherence rate was excellent with 100%. High system usability scores (i.e., mean 80%, range 55-97.5) and a significant Spearman's correlation with the Flow State Scale (r = .762, p = .017) further point to the high feasibility of the VBT. Neither demographic variables nor difficulties in dexterity related ADL affected the usability of the VBT.

CONCLUSION

This study demonstrates the high feasibility of a combined iTBS-VBT intervention. Moreover, the level of self-reported usability was related to flow experience. Whether this kind of combined iTBS-VBT intervention improves dexterity will be evaluated in a randomized controlled trial. Trial registration clincaltrials.gov NCT04699149, date of registration 1. June 2021.

Usability of Two New Interactive Game Sensor-Based Hand Training Devices in Parkinson's Disease

This pilot cross-sectional study aimed to evaluate the usability of two new interactive game sensor-based hand devices (GripAble and Smart Sensor Egg) in both healthy adults as well as in persons with Parkinson's Disease (PD). Eight healthy adults and eight persons with PD participated in this study. Besides a standardised usability measure, the state of flow after one training session and the effect of cognitive abilities on flow were evaluated. High system usability scores (SUS) were obtained both in healthy participants (72.5, IQR = 64.375-90, GripAble) as well as persons with PD (77.5, IQR = 70-80.625, GripAble; 77.5, IQR = 75-82.5, Smart Sensor Egg). Similarly, high FSSOT scores were achieved after one training session (42.5, IQR = 39.75-50, GripAble; 50, IQR = 47-50, Smart Sensor Egg; maximum score 55). Across both groups, FSSOT scores correlated significantly with SUS scores (r = 0.52, p = 0.039). Finally, MoCA did not correlate significantly with FSSOT scores (r = 0.02, p = 0.9). The present study shows high usability for both interactive game sensor-based hand training devices, for persons with PD and healthy participants.

Similarities, differences and overlaps between frailty and Parkinson's disease

Parkinson's disease is a neurodegenerative disorder clinically characterized by bradykinesia, rest tremor, rigidity, and postural and gait disturbances, which are frequently observed in older people. It also shows non-motor symptoms, such as depression, anxiety, cognitive impairment and dementia. The number of patients is gradually increasing worldwide. Aging is a risk factor for the onset of Parkinson's disease, and various physiological effects of aging influence its progression. Frailty is a geriatric syndrome in which the reversible and vulnerable status between robustness and disability is affected by various physiological stressors with aging. Frailty consists of physical, psychological and social aspects. Furthermore, sarcopenia, a syndrome characterized by the loss of muscle mass, strength and function, is also significantly associated with frailty. To maintain the quality of life of older people, frailty, including sarcopenia, should be quickly and appropriately managed. Polypharmacy is an important factor causing the progression of frailty in geriatric syndrome. Although Parkinson's disease and frailty have similar symptoms, and are considered to affect each other, the clinical features and mechanisms of both largely remain unclear. Nevertheless, little literature on the relationship between frailty and Parkinson's disease is currently available. This narrative review aims to clarify the relationships between Parkinson's disease and frailty, not only on the physical, but also on the mental, cognitive, and social aspects and issues regarding polypharmacy in Parkinson's disease explored by previous studies. Geriatr Gerontol Int 2022; 22: 259-270.

Pharmacological, Biochemical and Immunological Studies on Protective Effect of Mangiferin in 6-Hydroxydopamine (6-OHDA)-Induced Parkinson's Disease in Rats

Background:

Parkinson’s disease is a neurodegenerative disorder and is marked by inflammation and death of neurons in the striatum region of the midbrain. It has been reported that expression of NF-κB increases during Parkinson’s disease, which promotes oxidative stress, stimulates release of proinflammatory cytokines, and induces expression of nitric oxide. Therefore, in this study, we have used mangiferin a specific NF-κB inhibitor. Mangiferin is a polyphenolic compound traditionally used for its antioxidant and anti-inflammatory properties.

Methods:

The study utilized male Wistar rats weighing 200–250 g (56 rats; n = 8/group). On day “0,” stereotaxic surgery of rats was done to induce 6-hydroxydopamine lesioning in rats. Coordinates for substantia nigra were anteroposterior-2 mm, mediolateral-5 mm and dorsoventral-8.2 mm. After 14 days, those rats which show at least 210 contralateral rotations after administration of apomorphine (0.5 mg/kg S.C.) were selected for the study and were given treatment for 28 days. On day 28 of treatment, rats were subjected to behavioral studies to evaluate the effect of mangiferin and their brains were taken out after euthanasia to perform biochemical, molecular and immunological studies.

Results:

Treatment with mangiferin significantly improves the key parameters of locomotor activity and oxidative stress and reduces the parameters of inflammatory stress. Also, the activity of caspases was reduced. Significant decrease in activity of both cyclooxygenase 1 and 2 was also observed. Maximum improvement in all parameters was observed in rats treated with grouping of mangiferin 45 µg/kg and levodopa 10 mg/kg. Treatment with levodopa alone has no significant effect on biochemical and molecular parameters though it significantly improves behavioral parameters.

Conclusion:

Current treatment of Parkinson’s disease does not target progression of Parkinson’s disease. Results of this study suggest that mangiferin has protective effect in hemi-Parkinsonian rats. Therefore, the combination therapy of mangiferin and levodopa can be helpful in management of Parkinson’s disease.

GripAble: An accurate, sensitive and robust digital device for measuring grip strength

Introduction

Grip strength is a reliable biomarker of overall health and physiological well-being. It is widely used in clinical practice as an outcome measure. This paper demonstrates the measurement characteristics of GripAble, a wireless mobile handgrip device that measures grip force both isometrically and elastically-resisted for assessment and training of hand function.

Methods

A series of bench tests were performed to evaluate GripAble's grip force measurement accuracy and sensitivity. Measurement robustness was evaluated through repeated drop tests interwoven with error verification test phases.

Results

GripAble's absolute measurement error at the central position was under 0.81 and 1.67 kg (95^th percentiles; N = 47) when measuring elastically and isometrically, respectively, providing similar or better accuracy than the industry-standard Jamar device. Sensitivity was measured as 0.062 ± 0.015 kg (mean ± std; 95^th percentiles: [0.036, 0.089] kg; N = 47), independent of the applied force. There was no significant performance degradation following impact from 30 drops from a height >1.5 m.

Conclusion

GripAble is an accurate and reliable grip strength dynamometer. It is highly sensitive and robust, which in combination with other novel features (e.g. portability, telerehabilitation and digital data tracking) enable broad applicability in a range of clinical caseloads and environments.

Experimental validation of Vitex negundo leaves hydroalcoholic extract for neuroprotection in haloperidol induced parkinson's disease in rat

Parkinsonism is a neurodegenerative disease, mainly imbalance in dopamine and acetylcholine neurotransimitter in mid brain, which manifestation of dysfunctions of extrapyramidal like akinesia, tremor, rigidity and catalepsy etc., even cognitive and memory loss. The current study is framed to evaluate the effect of Vitex negundo (VNL) leaf extract in Haloperidol induced PD in rats. In vitro studies of antioxidant capacity were checked via DPPH and NO assays and identified its Acetylcholinesterase (AChE) inhibitory activity. Secondly the In vivo study of anti-PD activity in Haloperidol induced in rats were evaluated by Rotarod, morris water maze (MWM), cooks pole climb (CPC), actophotometer, novel object recognition (NOR), and T-maze were utilized to assess extrapyramidal, cognitive and memory function. Thirdly, changes in biomarker level viz. (AChE), butyrylcholinesterase. (BChE) in hippocampus and cortex, reduced glutathione (GSH), malondialdehyde (MDA), total protein (TP), superoxide dismutase (SOD), catalase (CAT), and dopamine level in the whole brain were measured. Finally, histopathology of hippocampus and cortex was examined at 40x magnification to access restoring integrity and maintaining the architecture of neuronal cell in the treatment group compared to control group and L-DOPA as a standard treatment group. V. negundo showed potent antioxidant potency on scavenging of DPPH (IC50 84.81 μg/ml) and NO (IC50 133.20 μg/ml) and possess AChE inhibitory potency (IC50 114.35 μg/ml) by in vitro studies. The Rotarod, MWM, CPC, Actophotometer, NOR, T-maze demonstrated that Haloperidol group administration declines performance time, ELT, TL and decreases locomotion, cognitive and memory respectively. The treatment of VNL 100, 200, and 400 mg/kg p.o. significantly (p < 0.05 to p < 0.0001) reversed. Whole brain AChE, BChE, and MDA level were significantly raised and GSH, TP, SOD, CAT and Dopamine were significantly declined in Haloperidol treated group rats, especially V. negundo 400 mg/kg p.o. highly significantly ameliorate the Haloperidol group altered pathological changes through the restoration of the cholinergic function, enhancing the antioxidant defense and by increasing the dopaminergic function. The current study provides validation of V. negundo for its anti-PD activity and could be a valuable source for the treatment of PD in future.

Nutritional status and dynapenia in people living with Parkinson's disease: a cross-sectional study

OBJECTIVE

This study aimed to evaluate the nutritional status and handgrip strength (HS) in patients with Parkinson's disease (PD).

METHODOLOGY

This is a cross-sectional study with outpatients in two treatment centers in the state of Pernambuco. Sociodemographic data, body mass index (BMI), waist circumference (WC), and calf circumference (CC) were collected. Body fat (BF) was assessed using electrical bioimpedance. Dynapenia was assessed using HS and dynapenic obesity was defined as very high WC associated with low HS. The Hoehn-Yahr scale was used for the staging of PD and the disease's severity was assessed by the Unified Parkinson's Disease Rating Scale (UPDRS).

RESULTS

The results showed that 77.2% were elderly, which were at II and III stages of UPDRS scale. Overweight and obesity were present in 44.3% and 27.8%. Dynapenia was found in 50.6%. A negative correlation was observed between HS with age, UPDRS II and III, and BF percentage. Dynapenic obesity in men was lower 37.5% compared to women 63.6%.

CONCLUSION

It is relevant to identify the functional capacity such as dynapenia and also the nutritional status in people living with neurodegenerative diseases of early onset, such as PD, so it is possible to develop strategies in prevention and treatment that can improve these conditions, considering its negative impact in PD.

Pisa syndrome: Pathophysiology, physical rehabilitation and falls risk

BACKGROUND

Pisa syndrome (PS) is a postural disorder characterised by lateral flexion of the spine (> 10°), predisposing the affected individuals to falls, and contributing to increased mortality in neurodegenerative diseases.

OBJECTIVE

An overview of currently applied therapeutic management options, primarily focused on specifically structured rehabilitation exercises, in conjunction with falls-risk assessment in the individuals affected by PS.

METHODS

A narrative literature review, augmented with the authors' own experience in physical rehabilitation management.

RESULTS

As individuals affected by PS are evidenced to be intrinsically exposed to higher falls-risk through acquired postural deformities, they often fall victims of traumatic accidents, occasionally also facing relocation into 24-hour nursing facilities due to the injuries sustained/resultant disability, consequently having overall quality of their life appreciably reduced.

CONCLUSIONS

sA comprehensive approach is postulated in designing optimal therapeutic management, comprised of the exercises controlling postural stability, whilst reducing lower back pain, and the ones also promoting specific skills essential for coping unassisted after an accidental fall effectively. Rehabilitation of individuals affected by PS should be a fully integrated service, eliminating all identified risk factors for falls. As clinical PS symptoms tend to recur after completion of a full course of therapeutic management, all PS patients should continue the pursuit of therapeutic exercises on an individual basis, to effectively retard their recurrence. In view of overall scarcity of clinical studies completed on the large population samples of PS patients, further in-depth research is still required to ensure higher credence to overall efficacy of the presently proposed therapeutic solutions.

NPT520-34 improves neuropathology and motor deficits in a transgenic mouse model of Parkinson's disease

NPT520-34 is a clinical-stage, small molecule being developed for the treatment of Parkinson's disease and other neurodegenerative disorders. The therapeutic potential of NPT520-34 was first suggested by findings from cell-based assays of alpha-synuclein (ASYN) clearance. As reported here, NPT520-34 was subsequently evaluated for therapeutically relevant actions in a transgenic animal model of Parkinson's disease that overexpresses human ASYN and in an acute lipopolysaccharide (LPS)-challenge model using wild-type mice. Daily administration of NPT520-34 to mThy1-ASYN (Line 61) transgenic mice for one or three months resulted in reduced ASYN pathology, reduced expression of markers of neuroinflammation, and improvements in multiple indices of motor function. In an LPS-challenge model using wild-type mice, a single-dose of NPT520-34 reduced LPS-evoked increases in the expression of several pro-inflammatory cytokines in plasma. These findings demonstrate the beneficial effects of NPT520-34 on both inflammation and protein-pathology endpoints, with consequent improvements in motor function in an animal model of Parkinson's disease. These findings further suggest that NPT520-34 may have two complementary actions: (1) to increase the clearance of neurotoxic protein aggregates and (2) to directly attenuate inflammation. NPT520-34 treatment may thereby address two of the predominate underlying pathophysiological aspects of neurodegenerative disorders such as Parkinson's disease.

Quantifying upper limb motor impairment in people with Parkinson's disease: a physiological profiling approach

BACKGROUND

Upper limb motor impairments, such as slowness of movement and difficulties executing sequential tasks, are common in people with Parkinson's disease (PD).

OBJECTIVE

To evaluate the validity of the upper limb Physiological Profile Assessment (PPA) as a standard clinical assessment battery in people with PD, by determining whether the tests, which encompass muscle strength, dexterity, arm stability, position sense, skin sensation and bimanual coordination can (a) distinguish people with PD from healthy controls, (b) detect differences in upper limb test domains between "off" and "on" anti-Parkinson medication states and (c) correlate with a validated measure of upper limb function.

METHODS

Thirty-four participants with PD and 68 healthy controls completed the upper limb PPA tests within a single session.

RESULTS

People with PD exhibited impaired performance across most test domains. Based on validity, reliability and feasibility, six tests (handgrip strength, finger-press reaction time, 9-hole peg test, bimanual pole test, arm stability, and shirt buttoning) were identified as key tests for the assessment of upper limb function in people with PD.

CONCLUSIONS

The upper limb PPA provides a valid, quick and simple means of quantifying specific upper limb impairments in people with PD. These findings indicate clinical assessments should prioritise tests of muscle strength, unilateral movement and dexterity, bimanual coordination, arm stability and functional tasks in people with PD as these domains are the most commonly and significantly impaired.

Functional improvement related to enrolment in a Parkinson's disease rehabilitation program

BACKGROUND

Parkinson's disease (PD) is a progressive neurodegenerative disorder with manifestations such as tremors, rigidity and bradykinesia.

OBJECTIVE

The objective of this study was to evaluate the efficacy of outpatient multidisciplinary rehabilitation.

METHODS

179 patients participated in the six-week program. The following outcomes were measured: Timed Up and Go (TUG), sit to stand five times (STSx5) and in 30 seconds (STS30), six minute walk distance (6MWD) and gait velocity (6MWV), MOCA, bilateral grip strength, 360-degree turn (360 R, 360 L) and bilateral nine hole peg test. Pre- and post- data was analyzed via paired t-tests. Multiple regression was used to determine age- or gender-affected outcomes.

RESULTS

Patients showed a statistically significant improvement (p < 0.05) in all outcomes. Mean TUG improved by 1.63 seconds (s), STSx5 by 4.19s, STS30 by 2.37 repetitions, 6MWD by 66.8 metres, 6MWV by 0.15 m/s, MOCA by 1.50 points, 360 R by 1.17s, 360 L by 1.60s, Grip R by 0.78 kg, Grip L by 0.95 kg, 9HP R by 1.71s and 9HP L by 1.58s. Gender had no influence. Age was a statistically significant predictor in STSx5 and 6MW.

CONCLUSIONS

An outpatient multidisciplinary program successfully decreased motor impairment and increased overall functional independence in PD.

Determinant factors of sarcopenia in individuals with Parkinson's disease

OBJECTIVE

Evaluate the occurrence of sarcopenia and determinant factors in individuals with Parkinson's disease (PD) in a city in northeastern Brazil.

METHODS

Case series with 77 men and women (adults and older adults) with PD. The risk of sarcopenia was determined using the SARC-F and SARC-CalF screening tools. The diagnosis of sarcopenia was based on the new consensus published by the European Working Group on Sarcopenia in Older People (EWGSOP2). Sarcopenic obesity was diagnosed based on the criteria proposed by Stenholm. Disease stage and severity were determined using the Hoehn and Yahr scale and the Unified Parkinson Disease Rating Scale, respectively.

RESULTS

The prevalence of sarcopenia was 19.5% and was associated with age, poor performance on activities of daily living and poor nutritional status. No significant association was found between the SARC-F score and the diagnosis of sarcopenia. The main factors that determined the variation in the parameters for the diagnosis of sarcopenia in the present sample were age, disease severity, body weight, and SARCF score.

CONCLUSION

Despite the low prevalence in the present study, sarcopenia progresses with the worsening of the nutritional status and functional capacity of individuals with PD. Further studies are needed on the factors involved in the genesis of sarcopenia. The SARC-F questionnaire is related to parameters for the diagnosis and severity of sarcopenia as well as the severity of PD.

The feasibility of muscle mitochondrial respiratory chain phenotyping across the cognitive spectrum in Parkinson's disease

INTRODUCTION

There has been little work on the relationship between sarcopenia, a progressive skeletal muscle disorder, and age-related neurodegenerative diseases such as Parkinson's disease (PD).

OBJECTIVES

We aimed to determine: 1) the feasibility of characterizing skeletal muscle across a range of cognitive function in PD; 2) if muscle mitochondrial respiratory chain (MRC) function and content are preserved in older adults with PD.

METHODS

Sarcopenia was defined using handgrip strength, chair rise and bioimpedance analysis. MRC function was assessed using phosphorous magnetic resonance spectroscopy (MRS) by estimating τ_1/2 PCr (s) (phosphocreatine half-time recovery) in the calf muscles following a bout of aerobic exercise. Biopsy of the vastus lateralis muscle was performed, and MRC content assessed by fluorescent immunohistochemistry for porin and components of MRC Complexes I and IV.

RESULTS

Nine participants (78% male; mean age 79.9; PD duration 3.3 years) were recruited. Four had cognitive impairment. Six participants had probable sarcopenia. Eight participants completed MRS and had mean (SD) τ_1/2 PCr of 37.8 (7.6) seconds, suggesting preserved mitochondrial function. Muscle biopsies were obtained in all and the procedure was well tolerated. Porin Z-score, a proxy for mitochondrial mass, was lower than expected compared to controls (0-89% of fibres with low porin). There was a small amount of Complex I (0.16-4.59%) and Complex IV (0-3.79%) deficiency.

CONCLUSIONS

Detailed phenotyping, muscle biopsy and imaging was feasible and acceptable across a spectrum of cognitive function in PD. Sarcopenia was relatively common and may be associated with lower mitochondrial mass and low levels of MRC deficiency.

What are the association patterns between handgrip strength and adverse health conditions? A topical review

Measures of handgrip strength can be used to conveniently assess overall muscle strength capacity. Although stand-alone measures of handgrip strength provide robust health information, the clinical meaningfulness to determine prevention and treatment options for weakness remains limited because the etiology of muscle weakness remains unclear. Moreover, clinical outcomes associated with handgrip strength are wide-ranging. Therefore, disentangling how handgrip strength is associated with health conditions that are metabolically or neurologically driven may improve our understanding of the factors linked to handgrip strength. The purpose of this topical review was to highlight and summarize evidence examining the associations of handgrip strength with certain health outcomes that are metabolically and neurologically driven. From this perusal of the literature, we posit that stand-alone handgrip strength be considered an umbrella assessment of the body systems that contribute to strength capacity, and a panoptic measurement of muscle strength that is representative of overall health status, not a specific health condition. Recommendations for future strength capacity–related research are also provided.

Wearable Nail Deformation Sensing for Behavioral and Biomechanical Monitoring and Human-Computer Interaction

The dynamics of the human fingertip enable haptic sensing and the ability to manipulate objects in the environment. Here we describe a wearable strain sensor, associated electronics, and software to detect and interpret the kinematics of deformation in human fingernails. Differential forces exerted by fingertip pulp, rugged connections to the musculoskeletal system and physical contact with the free edge of the nail plate itself cause fingernail deformation. We quantify nail warpage on the order of microns in the longitudinal and lateral axes with a set of strain gauges attached to the nail. The wearable device transmits raw deformation data to an off-finger device for interpretation. Simple motions, gestures, finger-writing, grip strength, and activation time, as well as more complex idioms consisting of multiple grips, are identified and quantified. We demonstrate the use of this technology as a human-computer interface, clinical feature generator, and means to characterize workplace tasks.

Association of Strength and Physical Functions in People with Parkinson's Disease

Background

Parkinson's disease is responsible for decrease of activities of daily living and mobility limitations. Association of strength with physical capacities and disease time can improve training methodologies and predict changes in physical fitness for this population, since the control center of movements and strength is the same.

Objective

Therefore, the aim of this study is to analyze if there are correlation between strength with functional tests (the sit-to-stand, the six-minute walk, and the timed-up-go) and disease time in people with Parkinson's disease.

Results

All functional tests correlations are significant, p < 0.05. The strength is positively correlated with the sit-to-stand and the six-minute walk. The strength is negatively correlated with the timed-up-go.

Conclusion

There are a correlation between strength with functional tests in people with PD, and changes in strength assessment can be used as predictor to changes in aerobic capacity.