Major Depressive Disorder (MDD) is one of the most disabling diseases in the world. MDD is traditionally diagnosed based on a patient’s symptoms, which can lead to misdiagnosis. Although the pathogenic mechanisms of MDD are unknown, several studies have identified mitochondrial dysfunction as a central factor in the onset and progression of MDD. In the context of MDD, alterations in mitochondrial metabolism can lead to imbalances in energy production and oxidative stress, contributing to the disorder´s underlying pathophysiological mechanisms. Consequently, the identification of mitochondrial dysfunction as a key biomarker for early and accurate diagnosis of MDD represents a significant challenge. Faced with the limits of traditional treatments with antidepressants, new pharmacological therapeutic targets are being investigated such as ketamine/esketamine, psychedelics, or anti-inflammatories. All of these drugs show potential antidepressant effects due to their speed of action and ability to modulate neuroplasticity and/or motor processing. In parallel, non-pharmacological therapeutic targets are studied, like Transcranial Magnetic Stimulation (TMS) and Deep Brain Stimulation (DBS), recognized for their ability to modulate neuronal activity and offer treatment alternatives. As cellular activity is directly related to mitochondrial respiration, the aim of this review is examining the link between mitochondrial dysfunction and MDD, assessing how mitochondrial biomarkers could provide a more objective and precise diagnostic tool, and exploring other treatments in addition to traditional antidepressants, with a specific focus on emerging therapeutic targets. Finally, a detailed analysis of the strengths, weaknesses, opportunities, and threats of these approaches was carried out, highlighting the key challenges that must be addressed.
27 February 2024 in Alzheimer's Research & Therapy
Background: GOIZ ZAINDU (“caring early” in Basque) is a pilot study to adapt the Finnish Geriatric Intervention Study to Prevent Cognitive Impairment and Disability (FINGER) methodology to the Basque population and evaluate the feasibility and adherence to a FINGER-like multidomain intervention program. Additional aims included the assessment of efficacy on cognition and data collection to design a large efficacy trial. Method: GOIZ ZAINDU is a 1-year, randomized, controlled trial of a multidomain intervention in persons aged 60+ years, with Cardiovascular Risk Factors, Aging and Dementia (CAIDE) risk score ≥ 6, no diagnosis of dementia, and below-than-expected performance in at least one of three cognitive screening tests. Randomization to a multidomain intervention (MD-Int) or regular health advice (RHA) was stratified by sex, age (>/≤ 75), and cognitive status (mild cognitive impairment (MCI)/normal cognition). MD-Int included cardiovascular risk factor control, nutritional counseling, physical activity, and cognitive training. The primary outcomes were retention rate and adherence to the intervention program. Exploratory cognitive outcomes included changes in the Neuropsychological Test Battery z-scores. Analyses were performed according to the intention to treat. Results: One hundred twenty-five participants were recruited (mean age: 75.64 (± 6.46); 58% women). The MD-Int (n = 61) and RHA (n = 64) groups were balanced in terms of their demographics and cognition. Fifty-two (85%) participants from the RHA group and 56 (88%) from the MD-Int group completed the study. More than 70% of the participants had high overall adherence to the intervention activities. The risk of cognitive decline was higher in the RHA group than in the MD-Int group in terms of executive function (p =.019) and processing speed scores (p =.026). Conclusions: The GOIZ-ZAINDU study proved that the FINGER methodology is adaptable and feasible in a different socio-cultural environment. The exploratory efficacy results showed a lower risk of decline in executive function and processing speed in the intervention group. These results support the design of a large-scale efficacy trial. Trial registration: GOIZ ZAINDU feasibility trial was approved and registered by the Euskadi Drug Research Ethics Committee (ID: PI2017134) on 23 January 2018. Retrospectively registered in ClinicalTrials.gov (NCT06163716) on 8 December 2023.
Neuroinflammation has a significant impact on different pathologies, such as stroke or spinal cord injury, intervening in their pathophysiology: expansion, progression, and resolution. Neuroinflammation involves oxidative stress, damage, and cell death, playing an important role in neuroplasticity and motor dysfunction by affecting the neuronal connection responsible for motor control. The diagnosis of this pathology is performed using neuroimaging techniques and molecular diagnostics based on identifying and measuring signaling molecules or specific markers. In parallel, new therapeutic targets are being investigated via the use of bionanomaterials and electrostimulation to modulate the neuroinflammatory response. These novel diagnostic and therapeutic strategies have the potential to facilitate the development of anticipatory patterns and deliver the most beneficial treatment to improve patients’ quality of life and directly impact their motor skills. However, important challenges remain to be solved. Hence, the goal of this study was to review the implication of neuroinflammation in the evolution of motor function in stroke and trauma patients, with a particular focus on novel methods and potential biomarkers to aid clinicians in diagnosis, treatment, and therapy. A specific analysis of the strengths, weaknesses, threats, and opportunities was conducted, highlighting the key challenges to be faced in the coming years.
Multiple evidences suggest that mitochondrial dysfunction is implicated in the pathogenesis of Parkinson’s disease via the selective cell death of dopaminergic neurons, such as that which occurs after prolonged exposure to the mitochondrial electron transport chain (ETC) complex I inhibitor, 1-methyl-4-phenyl-1,2,3,6-tetrahydropyrine (MPTP). However, the effects of chronic MPTP on the ETC complexes and on enzymes of lipid metabolism have not yet been thoroughly determined. To face these questions, the enzymatic activities of ETC complexes and the lipidomic profile of MPTP-treated non-human primate samples were determined using cell membrane microarrays from different brain areas and tissues. MPTP treatment induced an increase in complex II activity in the olfactory bulb, putamen, caudate, and substantia nigra, where a decrease in complex IV activity was observed. The lipidomic profile was also altered in these areas, with a reduction in the phosphatidylserine (38:1) content being especially relevant. Thus, MPTP treatment not only modulates ETC enzymes, but also seems to alter other mitochondrial enzymes that regulate the lipid metabolism. Moreover, these results show that a combination of cell membrane microarrays, enzymatic assays, and MALDI-MS provides a powerful tool for identifying and validating new therapeutic targets that might accelerate the drug discovery process.
Background: Stroke is commonly accompanied by motor disorders secondary to the initial injury, and at the mitochondrial level, there is an increase in oxidative stress, causing tissue damage and relating to alteration in motor function. Functional electrical stimulation (FES) therapies can be useful in stroke patients aimed at restoring motor function and improving life quality. Several studies have recently proposed that electrical stimulation modulates mitochondrial biogenesis and physiology; however, the effect of FES on individual complexes comprising the mitochondrial electron transport chain (mETC) remains unknown. Methods: To study the effect of FES therapy on the activity of the mETC, in vitro analyses were conducted using UV‐spectrophotometry of the activity of the complexes (I, II, and IV), glycerol‐3‐phosphate dehydrogenase (G3PDH), and monoamine oxidase (MAO) in peripheral blood mononuclear cells (PBMCs) obtained from stroke patients. Patients' activity of complex II and MAO was also determined in platelets. Analyses were measured before and after 12 rehabilitation sessions based on FES therapy combined with physical exercises. Results: The results showed that the activity of the mETC, G3PDH, and MAO was significantly reduced in pre‐intervention stroke patients compared to healthy volunteers, both in PBMCs and platelets, except for complex II in platelets and MAO in PBMCs. Interestingly, FES intervention increased the mETC, G3PDH, and MAO activity in both cell types of stroke patients. Conclusions: This preliminary study indicates that intervention can restore motor function and mitochondrial activity, which are damaged in stroke patients. However, more research is needed to determine if changes in mitochondrial activity can be used as biomarkers of the pathology and/or the efficacy of intervention.
High-level athletic performance requires the implementation of personalized strategies based on the analysis of metabolic pathways involved in energy production: phosphagen, glycolytic, and oxidative pathways. In this context, mitochondria play an essential role as the central regulator of energy production, being closely linked to these three pathways. Exercise boosts cellular respiration, which can also be optimized by nutritional interventions and targeted supplementation, promoting mitochondrial biogenesis, reducing oxidative stress and increasing ATP production. These metabolic adaptations improve athletic performance, accelerate recovery processes, and reduce the risk of injury, adapting to the physiological characteristics of each athlete. Moreover, some of these metabolic adaptations converge on specific targets whose expression or activity is also altered in mental disorders. Therefore, the aim of this review is to analyze mitochondrial adaptations induced by exercise and supplementation, evaluating their impact on the phosphagen, glycolytic, and oxidative metabolic pathways, as well as their relationship with optimizing performance and recovery in high-level athletes, with special attention to their potential application to mental health.