Dopamine-mediated autocrine inhibition of insulin secretion.

The aim of the present research was to explore the mechanisms underlying the role of dopamine in the regulation of insulin secretion in beta cells. The effect of dopamine on insulin secretion was investigated on INS 832/13 cell line upon glucose and other secretagogues stimulation. Results show that dopamine significantly inhibits insulin secretion stimulated by both glucose and other secretagogues, while it has no effect on the basal secretion. This effect requires the presence of dopamine during incubation with the various secretagogues. Both electron microscopy and immunohistochemistry indicate that in beta cells the D2 dopamine receptor is localized within the insulin granules. Blocking dopamine entry into the insulin granules by inhibiting the VMAT2 transporter with tetrabenazine causes a significant increase in ROS production. Our results confirm that dopamine plays an important role in the regulation of insulin secretion by pancreatic beta cells through a regulated and precise compartmentalization mechanisms.

Current nonstimulant medications for adults with attention-deficit/hyperactivity disorder.

INTRODUCTION: Stimulants, including methylphenidate and amphetamines, are the first-line pharmacological treatment of ADHD in adults. However, in patients who do not respond or poorly tolerate stimulants, non-stimulant medications are usually recommended. AREAS COVERED: The authors provide a narrative review of the literature on non-stimulant treatments for adult ADHD, including controlled and observational clinical studies conducted on adult samples. Atomoxetine has been extensively studied and showed significant efficacy in treating adult ADHD. Issues related to dosing, treatment duration, safety, and use in the case of psychiatric comorbidity are summarized. Among other compounds indicated for ADHD in adults, antidepressants sharing at least a noradrenergic or dopaminergic component, including tricyclic compounds, bupropion, and viloxazine, have shown demonstratable efficacy. Evidence is also available for antihypertensives, particularly guanfacine, as well as memantine, metadoxine, and mood stabilizers, while negative findings have emerged for galantamine, antipsychotics, and cannabinoids. EXPERT OPINION: While according to clinical guidelines, atomoxetine may serve as the only second-line option in adults with ADHD, several other nonstimulant compounds may be effectively used in order to personalize treatment based on comorbid conditions and ADHD features. Nevertheless, further research is needed to identify and test more personalized treatment strategies for adults with ADHD.

Therapeutic Drug Monitoring in Psychiatry: Enhancing Treatment Precision and Patient Outcomes.

Psychiatric disorders often require pharmacological interventions to alleviate symptoms and improve quality of life. However, achieving an optimal therapeutic outcome is challenging due to several factors, including variability in the individual response, inter-individual differences in drug metabolism, and drug interactions in polytherapy. Therapeutic drug monitoring (TDM), by measuring drug concentrations in biological samples, represents a valuable tool to address these challenges, by tailoring medication regimens to each individual. This review analyzes the current landscape of TDM in psychiatric practice, highlighting its significance in optimizing drug dosages, minimizing adverse effects, and improving therapeutic efficacy. The metabolism of psychiatric medications (i.e., mood stabilizers, antipsychotics, antidepressants) often exhibits significant inter-patient variability. TDM can help address this variability by enhancing treatment personalization, facilitating early suboptimal- or toxic-level detection, and allowing for timely interventions to prevent treatment failure or adverse effects. Furthermore, this review briefly discusses technological advancements and analytical methods supporting the implementation of TDM in psychiatric settings. These innovations enable quick and cost-effective drug concentration measurements, fostering the widespread adoption of TDM as a routine practice in psychiatric care. In conclusion, the integration of TDM in psychiatry can improve treatment outcomes by individualizing medication regimens within the so-called precision medicine.

Stress Assessment for Augmented Reality Applications Based on Head Movement Features.

Augmented reality is one of the enabling technologies of the upcoming future. Its usage in working and learning scenarios may lead to a better quality of work and training by helping the operators during the most crucial stages of processes. Therefore, the automatic detection of stress during augmented reality experiences can be a valuable support to prevent consequences on people's health and foster the spreading of this technology. In this work, we present the design of a non-invasive stress assessment approach. The proposed system is based on the analysis of the head movements of people wearing a Head Mounted Display while performing stress-inducing tasks. First, we designed a subjective experiment consisting of two stress-related tests for data acquisition. Then, a statistical analysis of head movements has been performed to determine which features are representative of the presence of stress. Finally, a stress classifier based on a combination of Support Vector Machines has been designed and trained. The proposed approach achieved promising performances thus paving the way for further studies in this research direction.

The C-terminus of the prototypical M2 muscarinic receptor localizes to the mitochondria and regulates cell respiration under stress conditions.

Muscarinic acetylcholine receptors are prototypical G protein-coupled receptors (GPCRs), members of a large family of 7 transmembrane receptors mediating a wide variety of extracellular signals. We show here, in cultured cells and in a murine model, that the carboxyl terminal fragment of the muscarinic M2 receptor, comprising the transmembrane regions 6 and 7 (M2tail), is expressed by virtue of an internal ribosome entry site localized in the third intracellular loop. Single-cell imaging and import in isolated yeast mitochondria reveals that M2tail, whose expression is up-regulated in cells undergoing integrated stress response, does not follow the normal route to the plasma membrane, but is almost exclusively sorted to the mitochondria inner membrane: here, it controls oxygen consumption, cell proliferation, and the formation of reactive oxygen species (ROS) by reducing oxidative phosphorylation. Crispr/Cas9 editing of the key methionine where cap-independent translation begins in human-induced pluripotent stem cells (hiPSCs), reveals the physiological role of this process in influencing cell proliferation and oxygen consumption at the endogenous level. The expression of the C-terminal domain of a GPCR, capable of regulating mitochondrial function, constitutes a hitherto unknown mechanism notably unrelated to its canonical signaling function as a GPCR at the plasma membrane. This work thus highlights a potential novel mechanism that cells may use for controlling their metabolism under variable environmental conditions, notably as a negative regulator of cell respiration.

In-vitro Approaches to Investigate the Detrimental Effect of Light on Dopaminergic Neurons.

Our recent study revealed that fluorescent lamp light can penetrate deep into the brain of mice and rats leading to the development of typical histological characteristics associated with Parkinson's disease such as the loss of dopamine neurons in the substantia nigra. Monochromatic LED lights were thus used in this work to deepen our knowledge on the effects of the major wavelength peaks of fluorescent light on mouse and human dopaminergic cells. In particular, we exposed immortalized dopaminergic MN9D neuronal cells, primary cultures of mouse mesencephalic dopaminergic cells and human dopaminergic neurons differentiated from induced pluripotent stem cells (hiPSC) to different LED light wavelengths. We found that chronic exposure to LED light reduced overall undifferentiated MN9D cell number, with the most significant effects observed at wavelengths of 485 nm and 610 nm. Moreover, LED light especially at 610 nm was able to negatively impact on the survival of mouse mesencephalic dopaminergic cells and of human dopaminergic neurons derived from hiPSC. Notably, differentiated MN9D dopaminergic cells, which closely resemble mature dopamine neuronal phenotype, acutely exposed for 3 h at 610 nm, showed a clear increase in ROS production and cytotoxicity compared to controls undifferentiated MN9D cells. These increases were even more pronounced by the co-treatment with the oxidative agent H2O2. Collectively, these findings suggest that specific wavelengths, particularly those capable of penetrating deep into the brain, could potentially pose an environmental hazard in relation to Parkinson's disease.

Melanocortin receptor 4 as a new target in melanoma therapy: Anticancer activity of the inhibitor ML00253764 alone and in association with B-raf inhibitor vemurafenib.

The aim of our study is to investigate in vitro and in vivo MC4R as a novel target in melanoma using the selective antagonist ML00253764 (ML) alone and in combination with vemurafenib, a B-rafV600E inhibitor. The human melanoma B-raf mutated A-2058 and WM 266-4 cell lines were used. An MC4R null A-2058 cell line was generated using a CRISPR/Cas9 system. MC4R protein expression was analysed by western blotting, immunohistochemistry, and immunofluorescence. Proliferation and apoptotic assays were performed with ML00253764, whereas the synergism with vemurafenib was evaluated by the combination index (CI) and Loewe methods. ERK1/2 phosphorylation and BCL-XL expression were quantified by western blot. In vivo experiments were performed in Athymic Nude-Foxn1nu male mice, injecting subcutaneously melanoma cells, and treating animals with ML, vemurafenib and their concomitant combination. Comet and cytome assays were performed. Our results show that human melanoma cell lines A-2058 and WM 266-4, and melanoma human tissue, express functional MC4R receptors on their surface. MC4R receptors on melanoma cells can be inhibited by the selective antagonist ML, causing antiproliferative and proapoptotic activity through the inhibition of phosphorylation of ERK1/2 and a reduction of BCL-XL. The concomitant combination of vemurafenib and ML caused a synergistic effect on melanoma cells in vitro and inhibited in vivo tumor growth in a preclinical model, without causing mouse weight loss or genotoxicity. Our original research contributes to the landscape of pharmacological treatments for melanoma, providing MC4R antagonists as drugs that can be added to established therapies.

Immersive virtual reality for shoulder rehabilitation: evaluation of a physical therapy program executed with oculus quest 2.

BACKGROUND: Virtual Reality (VR) systems have been increasingly used across several medical fields. A crucial preliminary step for developing optimized VR-based applications for rehabilitation purposes is identifying potential interventions to meet the requirements necessary to satisfy end-users' needs. This study aims to assess the acceptability, usability, and appropriateness of a VR physical therapy program executed with Oculus Quest 2 by expert physiotherapists of shoulder musculoskeletal rehabilitation. METHODS: Eleven physiotherapists were enrolled to test a VR program for shoulder musculoskeletal rehabilitation. At the end of each session, physiotherapists completed three questionnaires about the acceptability, usability, and appropriateness of the VR system and application, investigating aspects such as wearability, safety, stability, ease of control, comfort, size, utility, playability, and use mode. RESULTS: The acceptability questionnaire revealed that all the physiotherapists found the VR system easy to wear and control, very confident, and safe. The usability questionnaire showed that most physiotherapists (73%) found the VR application entertaining, although only 45% said the system could be used independently by patients without the support of a therapist. Many physiotherapists found the use of the VR application appropriate for patients with rotator cuff tears treated conservatively (63.6%) or surgically (54.5%), for patients with shoulder osteoarthritis treated conservatively (72.7%), for patients with shoulder osteoarthritis after surgical treatment (63.6%). 91% of physiotherapists think it would be best for patients to use the VR system under the supervision of a therapist and not independently in a home setting. CONCLUSIONS: The use of VR in orthopaedic rehabilitation is encouraging, although further efforts are needed to increase the independent use of patients without the supervision of a physiotherapist. Moreover, future studies should strive to ensure the clinical effectiveness of VR rehabilitation in reaching therapeutic goal settings.

Performance Evaluation of an Immersive Virtual Reality Application for Rehabilitation after Arthroscopic Rotator Cuff Repair.

Few studies have evaluated the effectiveness of shoulder rehabilitation in virtual environments. The objective of this study was to investigate the performance of a custom virtual reality application (VR app) with a stereophotogrammetric system considered the gold standard. A custom VR app was designed considering the recommended rehabilitation exercises following arthroscopic rotator cuff repair. Following the setting of the play space, the user's arm length, and height, five healthy volunteers performed four levels of rehabilitative exercises. Results for the first and second rounds of flexion and abduction displayed low total mean absolute error values and low numbers of unmet conditions. In internal and external rotation, the number of times conditions were not met was slightly higher; this was attributed to a lack of isolated shoulder movement. Data is promising, and volunteers were able to reach goal conditions more often than not. Despite positive results, more literature comparing VR applications with gold-standard clinical parameters is necessary. Nevertheless, results contribute to a body of literature that continues to encourage the application of VR to shoulder rehabilitation programs.

Methadone dose escalation in patients with opioid use disorder and cancer as a strategy for controlling cancer-related pain: A case series.

OBJECTIVES: Opioid use disorder (OUD) and cancer gained attention as co-occurring diseases in the last 2 decades due to the possible relationship between opioid prescriptions for cancer pain and the risk of developing substance use disorder in cancer patients. However, little is known about patients previously diagnosed with OUD who develop cancer and how to manage both OUD symptoms and control pain. METHODS: The present case series deals with this subpopulation and proposes a dose escalation of methadone to control both the cancer-related pain and drug addiction symptoms. RESULTS: This approach is peculiar because methadone is not used as a first-line treatment in cancer pain management and is not often used as a second-line treatment as well. Our 4 patients experienced good clinical control of symptoms and no major adverse reactions. SIGNIFICANCE OF RESULTS: The subgroup of patients with OUD who develop cancer could be the perfect population to reconsider the use of methadone as a first-line treatment for cancer pain. Prospective studies are needed to evaluate the efficacy and safety of increasing doses of methadone in these patients to validate our clinical approach.

Mechanism and clinical evidence of immunotherapy in allergic rhinitis.

Allergic rhinitis is a common upper airway disease caused by hypersensitivity to various aeroallergens. It causes increased inflammation throughout the body and may be complicated by other otolaryngological pathologies such as chronic hyperplastic eosinophilic sinusitis, nasal polyposis, and serous otitis media. Allergic rhinitis is an IgE-mediated disease and immunotherapy can be a possible approach for patients to limit the use of antihistamines and corticosteroids. There is evidence that allergen immunotherapy can prevent the development of new sensitizations and reduce the risk of later development of asthma in patients with allergic rhinitis. However, some patients do not benefit from this approach and the efficacy of immunotherapy in reducing the severity and relapse of symptoms is still a matter of debate. This review highlights new aspects of allergic rhinitis with a particular focus on the impact of sexual dimorphism on the disease manifestation and efficacy to the allergen specific immunotherapy.

A 5-Year Study of Antiseizure Medications (ASMs) Monitoring in Patients with Neuropsychiatric Disorders in an Italian Clinical Center.

Despite receiving appropriate antiseizure medications (ASMs), a relevant percentage of neuropsychiatric patients do not benefit from this approach, and one reason is subtherapeutic ASMs plasma concentration (C(p)) due to improper drug adherence, interindividual pharmacokinetic differences, or metabolic interactions among different drugs. For these reasons, therapeutic drug monitoring (TDM) by measuring ASMs C(p) is an effective tool that improves pharmacological therapies in clinical practice. Based on these premises, in the present real-world study, we analyzed the C(p) of the most used ASMs in diverse medical conditions, which were assayed during the years 2018-2022 at the University Hospital of Pisa, including about 24,000 samples. This population was largely heterogeneous, and our database did not contain clinical information about the patients. The most used ASMs were Valproate (VPA: 54.5%) and Levetiracetam (LEV: 18.6%), followed by Oxcarbazepine (OxCBZ: 8.3%) and Carbamazepine (CBZ: 7.2%), whereas the associations LEV/VPA, Ethosuximide (ESM)/VPA, and CBZ/VPA were the most frequently proposed. In about 2/3 of assays, ASMs C(p) was in range, except for VPA, which was underdosed in almost half of the samples. Importantly, toxic levels of ASMs C(p) were found very rarely. For VPA, there was a decrease of mean C(p) across ages, from adolescents to older patients, while the C(p) of LEV, CBZ, OxCBZ, and Topiramate (TPM) showed a slight tendency to increase. When we compared females and males, we found that for VPA, the average age was higher for females, whereas women taking Lamotrigine (LTG) and OxCBZ were younger than men. Then, comparing ASMs used in neurologic and psychiatric disorders, based on the request form, it emerged that the mean C(p) of CBZ, OxCBZ, and LTG on samples collected in the Psychiatric Unit was lower compared to the Neurology and Child Neuropsychiatry Units. Finally, the ASMs subjected to multiple dosing starting from an initial subtherapeutic C(p) increased their level at different time points within a year, reaching the reference range for some of them. In conclusion, the present study suggests that TDM is widely applied to monitor ASMs C(p), finding many of them within the reference range, as a demonstration of its utility in clinical practice.

Valproate and lithium: Old drugs for new pharmacological approaches in brain tumors?

Beyond its use as an antiepileptic drug, over time valproate has been increasingly used for several other therapeutic applications. Among these, the antineoplastic effects of valproate have been assessed in several in vitro and in vivo preclinical studies, suggesting that this agent significantly inhibits cancer cell proliferation by modulating multiple signaling pathways. During the last years various clinical trials have tried to find out if valproate co-administration could enhance the antineoplastic activity of chemotherapy in glioblastoma patients and in patients suffering from brain metastases, demonstrating that the inclusion of valproate in the therapeutic schedule causes an improved median overall survival in some studies, but not in others. Thus, the effects of the use of concomitant valproate in brain cancer patients are still controversial. Similarly, lithium has been tested as an anticancer drug in several preclinical studies mainly using the unregistered formulation of lithium chloride salts. Although, there are no data showing that the anticancer effects of lithium chloride are superimposable to the registered lithium carbonate, this formulation has shown preclinical activity in glioblastoma and hepatocellular cancers. However, few but interesting clinical trials have been performed with lithium carbonate on a very small number of cancer patients. Based on published data, valproate could represent a potential complementary therapeutic approach to enhance the anticancer activity of brain cancer standard chemotherapy. Same advantageous characteristics are less convincing for lithium carbonate. Therefore, the planning of specific phase III studies is necessary to validate the repositioning of these drugs in present and future oncological research.

Pharmacological Strategies for Bipolar Disorders in Acute Phases and Chronic Management with a Special Focus on Lithium, Valproic Acid, and Atypical Antipsychotics.

Bipolar disorders (BDs) are a heterogeneous group of severe affective disorders generally described by the alternation of (hypo)manic, depressive, and mixed phases, with euthymic intervals of variable duration. BDs are burdened with high psychiatric and physical comorbidity, increased suicide risk and reduced life expectancy. In addition, BDs can progress into complicated forms (e.g., mixed states, rapid/irregular cycling), which are more difficult to treat and often require personalized pharmacological combinations. Mood stabilizers, particularly Lithium and Valproic acid (VPA), still represent the cornerstones of both acute and chronic pharmacotherapies of BDs. Lithium is the gold standard in BD-I and BDII with typical features, while VPA seems more effective for atypical forms (e.g., mixed-prevalence and rapid-cycling). However, despite appropriate mood stabilization, many patients show residual symptoms, and more than a half recur within 1-2 years, highlighting the need of additional strategies. Among these, the association of atypical antipsychotics (AAPs) with mood stabilizers is recurrent in the treatment of acute phases, but it is also being growingly explored in the maintenance pharmacotherapy. These combinations are clinically more aggressive and often needed in the acute phases, whereas simplifying pharmacotherapies to mood stabilizers only is preferable in the long-term, whenever possible. When mood stabilizers are not enough for maintenance treatment, Quetiapine and, less consistently, Aripiprazole have been proposed as the most advisable adjunctive strategies, for their safety and tolerability profiles. However, in view of the increased risk of serious adverse effects, a careful patient-centered balance between costs and benefits is mandatory.

Long-term treatment of adult ADHD in a naturalistic setting: Clinical predictors of attrition, medication choice, improvement, and response.

OBJECTIVES: The aim of this study was to identify clinical predictors of treatment attrition, medication choice, improvement and response to pharmacotherapy in adult attention-deficit/hyperactivity disorder (ADHD). METHODS: 150 ADHD patients were enrolled and naturalistically followed-up for at least 4 months. Conners' Adult ADHD Rating Scales-Observer: Screening Version (CAARS-O:SV) were used to measure ADHD severity. RESULTS: 58 subjects (38.7%) were lost at follow-up, while 75 (50%) completed follow-up assessment, on average after 26.05 ± 11.99 weeks; 35 were treated with atomoxetine (ATX) and 40 with methylphenidate (MPH). Treatments were moderately effective (d = 0.72) and 37 patients (49.3%) were responders (≥30% CAARS-O:SV decrease). Patients lost at follow-up had lower inattentive symptoms, less generalised anxiety and family history of bipolar disorder, more amphetamine use disorder than follow-up completers. Compared to ATX-treated subjects, MPH-treated patients had greater severity of hyperactivity/impulsivity and were more frequently diagnosed with alcohol use disorder. While MPH and ATX showed similar efficacy, more pronounced improvements were observed in patients with combined ADHD, anxiety and substance use disorders. ADHD severity and comorbid substance use positively predicted response. CONCLUSIONS: Consensus-based hierarchical treatment of ADHD comorbidity is not consistently supported. Comorbid anxiety, mood and substance use disorders should not discourage the treatment of adult ADHD.

Melatonin as a Chronobiotic with Sleep-promoting Properties.

The use of exogenous melatonin (exo-MEL) as a sleep-promoting drug has been under extensive debate due to the lack of consistency of its described effects. In this study, we conduct a systematic and comprehensive review of the literature on the chronobiotic, sleep-inducing, and overall sleep-promoting properties of exo-MEL. To this aim, we first describe the possible pharmacological mechanisms involved in the sleep-promoting properties and then report the corresponding effects of exo-MEL administration on clinical outcomes in: a) healthy subjects, b) circadian rhythm sleep disorders, c) primary insomnia. Timing of administration and doses of exo-MEL received particular attention in this work. The exo-MEL pharmacological effects are hereby interpreted in view of changes in the physiological properties and rhythmicity of endogenous melatonin. Finally, we discuss some translational implications for the personalized use of exo-MEL in the clinical practice.

Triple Diagnosis of Attention-Deficit/Hyperactivity Disorder with Coexisting Bipolar and Alcohol Use Disorders: Clinical Aspects and Pharmacological Treatments.

Attention-Deficit/Hyperactivity Disorder (ADHD), Bipolar Disorder (BD) and Alcohol Use Disorder (AUD) are common medical conditions often coexisting and exerting mutual influence on disease course and pharmacological treatment response. Each disorder, when considered separately, relies on different therapeutic approaches, making it crucial to detect the plausible association between them. Treating solely the emerging condition (e.g., alcoholism) and disregarding the patient's whole psychopathological ground often leads to treatment failure and relapse. Clinical experience and scientific evidence rather show that tailoring treatments for these three conditions considering their co-occurrence as a sole complex disorder yields more fulfilling and durable clinical outcomes. In light of the above considerations, the purpose of the present review is to critically discuss the pharmacological strategies in the personalized treatment of complex conditions defined by ADHD-bipolarityalcoholism coexistence.

GPCRs in Intracellular Compartments: New Targets for Drug Discovery.

The architecture of eukaryotic cells is defined by extensive membrane-delimited compartments, which entails separate metabolic processes that would otherwise interfere with each other, leading to functional differences between cells. G protein-coupled receptors (GPCRs) are the largest class of cell surface receptors, and their signal transduction is traditionally viewed as a chain of events initiated from the plasma membrane. Furthermore, their intracellular trafficking, internalization, and recycling were considered only to regulate receptor desensitization and cell surface expression. On the contrary, accumulating data strongly suggest that GPCRs also signal from intracellular compartments. GPCRs localize in the membranes of endosomes, nucleus, Golgi and endoplasmic reticulum apparatuses, mitochondria, and cell division compartments. Importantly, from these sites they have shown to orchestrate multiple signals that regulate different cell pathways. In this review, we summarize the current knowledge of this fascinating phenomenon, explaining how GPCRs reach the intracellular sites, are stimulated by the endogenous ligands, and their potential physiological/pathophysiological roles. Finally, we illustrate several mechanisms involved in the modulation of the compartmentalized GPCR signaling by drugs and endogenous ligands. Understanding how GPCR signaling compartmentalization is regulated will provide a unique opportunity to develop novel pharmaceutical approaches to target GPCRs and potentially lead the way towards new therapeutic approaches.

Human reaction time in a mixed reality environment.

Over the last few years applications based on the use of immersive environments, where physical and digital objects coexist and interact, have gained widespread attention. Thanks to the development of new visualization devices, even at low cost, and increasingly effective rendering and processing techniques, these applications are reaching a growing number of users. While the adoption of digital information makes it possible to provide immersive experiences in a number of different applications, there are still many unexplored aspects. In this work, a preliminary step to understand the impact of the scene content on human perception of the virtual 3D elements in a mixed reality has been performed. To this aim, a subjective test was designed and implemented to collect the reaction time of a set of users in a mixed reality application. In this test each user was asked to wear an augmented reality headset and to catch a virtual objects randomly appearing in the subject's field of view. We first estimated the detection accuracy through omitted, anticipated, and completed responses; then we related stimulus location, scene content and estimated accuracy. For this purpose, the area of stimulus presentation was divided into upper, lower, right, left, inner, and outer, to understand in which area responses were omitted and anticipated with respect to the central point of view. Experimental results show that, in addition to the saliency of the real scene, natural body gesture technology and limited field of view influenced human reaction time.

Virtual Reality for Shoulder Rehabilitation: Accuracy Evaluation of Oculus Quest 2.

Virtual reality (VR) systems are becoming increasingly attractive as joint kinematics monitoring systems during rehabilitation. This study aimed to evaluate the accuracy of the Oculus Quest 2 in measuring translational and rotational displacements. As the Oculus Quest 2 was chosen for future applications in shoulder rehabilitation, the translation range (minimum: ~200 mm, maximum: ~700 mm) corresponded to the forearm length of the 5th percentile female and the upper limb length of the 95th percentile male. The controller was moved on two structures designed to allow different translational displacements and rotations in the range 0-180°, to cover the range of motion of the upper limb. The controller measures were compared with those of a Qualisys optical capture system. The results showed a mean absolute error of 13.52 ± 6.57 mm at a distance of 500 mm from the head-mounted display along the x-direction. The maximum mean absolute error for rotational displacements was found to be 1.11 ± 0.37° for a rotation of 40° around the z-axis. Oculus Quest 2 is a promising VR tool for monitoring shoulder kinematics during rehabilitation. The inside-out movement tracking makes Oculus Quest 2 a viable alternative to traditional motion analysis systems.