Mitochondrial transplantation exhibits neuroprotective effects and improves behavioral deficits in an animal model of Parkinson's disease

Mitotherapy in Alzheimer's and Parkinson's diseases: A systematic review of preclinical studies

BACKGROUND

Alzheimer's disease (AD) and Parkinson's disease (PD) are prevalent neurodegenerative disorders and strongly affect both the patients' lives and their caregivers. Strategy to improve and restore mitochondrial function, as well as to treat mitochondria-associated diseases, as observed in the pathophysiology of AD and PD. The current study aimed to investigate the potential of mitotherapy in AD and PD in preclinical studies.

METHODS

We conducted a systematic search of articles in English related to mitotherapy in AD and PD animal models published until October 2024 in the selected bibliographic databases, including PubMed, Scopus, EMBASE, and Google Scholar, and the reference lists of relevant review articles published. The quality of the final selected studies was assessed using the Collaborative Approach to Meta-Analysis and Review of Animal Studies (CAMARADES) checklists and the SYRCLE risk of bias tool. The initial search resulted in 231 studies, and after screening the titles and abstracts, 30 studies were recognized. Finally, 7 studies met the inclusion criteria.

RESULTS

Despite restricted knowledge of the mitotherapy mechanisms, evidence shows that exogenous mitochondria exert neuroprotective effects via improving mitochondrial function, reducing oxidative stress and inflammation in preclinical models of AD and PD.

CONCLUSION

This systematic review summarizes the preclinical studies on mitotherapy and provides evidence favoring mitochondria transplantation's protective effects in animal PD and AD models.

Enhancing Mitochondrial Function Through Pharmacological Modification: A Novel Approach to Mitochondrial Transplantation in a Sepsis Model

Background/Objectives: Sepsis continues to be a significant global health issue, with current treatments primarily focused on antibiotics, fluid resuscitation, vasopressors, or steroids. Recent studies have started to explore mitochondrial transplantation as a potential treatment for sepsis. This study aims to evaluate the effects of enhanced mitochondrial transplantation on sepsis. Methods: We examined various mitochondrial-targeting drugs (formoterol, metformin, CoQ10, pioglitazone, fenofibrate, and elamipretide) to improve mitochondrial function prior to transplantation. Mitochondrial function was assessed by measuring the oxygen consumption rate (OCR) and analyzing the expression of genes related to mitochondrial biogenesis. Additionally, the effects of enhanced mitochondrial transplantation on inflammation were investigated using an in vitro sepsis model with THP-1 cells. Results: Formoterol significantly increased mitochondrial biogenesis, as evidenced by enhanced oxygen consumption rates and the upregulation of mitochondrial-associated genes, including those related to biogenesis (PGC-1α: 1.56-fold, p < 0.01) and electron transport (mt-Nd6: 1.13-fold, p = 0.16; mt-Cytb: 1.57-fold, p < 0.001; and mt-Co2: 1.44-fold, p < 0.05). Furthermore, formoterol-enhanced mitochondrial transplantation demonstrated a substantial reduction in TNF-α levels in LPS-induced hyperinflammatory THP-1 cells (untreated: 915.91 ± 12.03 vs. formoterol-treated: 529.29 ± 78.23 pg/mL, p < 0.05), suggesting its potential to modulate immune responses. Conclusions: Mitochondrial transplantation using drug-enhancing mitochondrial function might be a promising strategy in sepsis.

Intestinal microbiota distribution and changes in different stages of Parkinson's disease: A meta-analysis, bioinformatics analysis and in vivo simulation

Parkinson's disease (PD) is a progressive disease that requires effective staging management. The role of intestinal microbiota in PD has been studied, but its changes at different stages are not clear. In this study, meta- analysis, bioinformatics analysis and in vivo simulation were used to explore the intestinal microbiota distribution of PD patients and models at different stages. Two PD models at different stages were established in rotenone-treated rats and MPTP-induced mice. The differences in the intestinal microbiota among the different stages of PD patients or models were compared and analyzed. There were significant differences between PD patients and controls, including Actinobacteriota, Deltaproteobacteria, Clostridiales, Lachnospiraceae, Parabacteroides, etc. Through bioinformatics analysis, we revealed significant differences between PD patients at different stages and controls, including Actinobacteriota, Methanobacteria, Erysipelotrichales, Prevotellaceae, Parabacteroides, Parabacteroides gordonii, etc. Through meta-analysis, we found that Actinobacteriota and Erysipelotrichaceae had significantly increased in the chronic MPTP model, while Prevotellaceae had significantly decreased. PD rats and mice presented significant damage to motor function, coordination, autonomous activity ability and gastrointestinal function, and the damage in the late group was greater than that in the early group. There were significant differences in intestinal microbiota between PD patients or models at different stages and the control groups. In the early stage, the dominant microbiota are Akkermansia, Alistipes, Anaerotruncus, Bilophila, Rikenellaceae, Verrucomicrobia and Verrucomicrobiae, whereas in the late stage, the dominant microbiota are Actinobacteriota and Erysipelotrichaceae. These differences can lay a foundation for subsequent research on the treatment and mechanism of PD at different stages.

Saikosaponins from Bupleurum scorzonerifolium Willd. alleviates microglial pyroptosis in depression by binding and inhibiting P2X7 expression

BACKGROUND

The major depressive disorder (MDD) is a heterogeneous condition and characterized by a high recurrence rate, with neuroinflammation playing a significant role in its various potential pathologies. In recent years, neuronal pyroptosis induced by neuroinflammation has garnered increasing attention in depression research. Bupleurum scorzonerifolium Willd. is depression research in traditional Chinese medicine prescriptions to treat depression and exhibits notable anti-inflammatory properties. Saikosaponins (SSs) are the primary active components of Bupleurum scorzonerifolium Willd., although their mechanism of action in relation to anti-depressive effects remains unclear.

PURPOSE

The purpose is to evaluate the efficacy of Chinese herbal medicine in treating depression through the lens of modern pharmacology. Additionally, it aims to explore the potential value of new mechanisms in the treatment of depression.

STUDY DESIGN AND METHODS

An in vivo model of depression was established by intraperitoneal injection of LPS. HE staining, Nissl staining, and Golgi staining were used to evaluate the effectiveness of depression treatments in each group of mice. The activation of microglia was analyzed using immunofluorescence to evaluate the anti-inflammatory effects of drugs. In vitro models, N9 cells induced by LPS and ATP used CCK-8 assay, and lactate dehydrogenase assay were conducted to explore the therapeutic effect of the SSs. Western blot and immunohistochemical methods were employed to investigate the expression of P2X7 and apoptosis-related proteins. BzATP was introduced as a P2X7 agonist, and CETSA and CHX pulse-chase assay were utilized to verify the combined action and stability of the SSs with P2X7.

RESULTS

57 triterpenoid saponin compounds were identified by Unifi in Bupleurum scorzonerifolium Willd. In both in vivo and in vitro models, the SSs has been shown to significantly improve depression-like behavior, reduce central inflammation, and significantly inhibit neuronal pyroptosis in mice. The SSs can significantly decrease the expression of P2X7 in the brains of depressed mice and enhance the stability of P2X7 protein in N9 cells.

CONCLUSION

SSs in Bupleurum scorzonerifolium Willd. bind and inhibit the P2X7 receptor to alleviate neuronal pyroptosis and improve symptoms of depression.

Mechanism and Clinical Application Prospects of Mitochondrial DNA Single Nucleotide Polymorphism in Neurodegenerative Diseases

Mitochondrial dysfunction is well recognized as a critical component of the complicated pathogenesis of neurodegenerative diseases such as Alzheimer's disease, Parkinson's disease, and Huntington's disease. This review investigates the influence of mitochondrial DNA single nucleotide polymorphisms on mitochondrial function, as well as their role in the onset and progression of these neurodegenerative diseases. Furthermore, the contemporary approaches to mitochondrial regulation in these disorders are discussed. Our objective is to uncover early diagnostic targets and formulate precision medicine strategies for neurodegenerative diseases, thereby offering new paths for preventing and treating these conditions.

Mechanism and prospects of mitochondrial transplantation for spinal cord injury treatment

Spinal cord injury (SCI) involves a continuous and dynamic cascade of complex reactions, with mitochondrial damage and dysfunction-induced energy metabolism disorders playing a central role throughout the process. These disorders not only determine the severity of secondary injuries but also influence the potential for axonal regeneration. Given the critical role of energy metabolism disturbances in the pathology of SCI, strategies such as enhancing mitochondrial transport within axons to alleviate local energy deficits, or transplanting autologous or allogeneic mitochondria to restore energy supply to damaged tissues, have emerged as potential approaches for SCI repair. These strategies also aim to modulate local inflammatory responses and apoptosis. Preclinical studies have initially demonstrated that mitochondrial transplantation (MT) significantly reduces neuronal death and promotes axonal regeneration following spinal cord injury. MT achieves this by regulating signaling pathways such as MAPK/ERK and PI3K/Akt, promoting the expression of growth-associated protein-43 (GAP-43) in neurons, and inhibiting the expression of apoptosis-related proteins like Grp78, Chop, and P-Akt, thereby enhancing the survival and regeneration of damaged neurons. Additionally, MT plays a role in promoting the expression of vascular endothelial growth factor, facilitating tissue repair, and reducing the secretion of pro-inflammatory cytokines such as TNF-α, IL-1β, and IL-6. Furthermore, MT modulates neuronal apoptosis and inflammatory responses by decreasing the expression of p-JNK, a member of the MAPK family. In summary, by reviewing the detailed mechanisms underlying the cascade of pathological processes in SCI, we emphasize the changes in endogenous mitochondria post-SCI and the potential of exogenous MT in SCI repair. This review aims to provide insights and a basis for developing more effective clinical treatments for SCI.

Mitochondrion-based organellar therapies for central nervous system diseases

As most traditional drugs used to treat central nervous system (CNS) diseases have a single therapeutic target, many of them cannot treat complex diseases or diseases whose mechanism is unknown and cannot effectively reverse the root changes underlying CNS diseases. This raises the question of whether multiple functional components are involved in the complex pathological processes of CNS diseases. Organelles are the core functional units of cells, and the replacement of damaged organelles with healthy organelles allows the multitargeted and integrated modulation of cellular functions. The development of therapies that target independent functional units in the cell, specifically, organelle-based therapies, is rapidly progressing. This article comprehensively discusses the pathogenesis of mitochondrial homeostasis disorders, which involve mitochondria, one of the most important organelles in CNS diseases, and the machanisms of mitochondrion-based therapies, as well as current preclinical and clinical studies on the efficacy of therapies targeting mitochondrial to treat CNS diseases, to provide evidence for use of organelle-based treatment strategies in the future.

Stroke studies in large animals: Prospects of mitochondrial transplantation and enhancing efficiency using hydrogels and nanoparticle-assisted delivery

One of the most frequent reasons for mortality and disability today is acute ischemic stroke, which occurs by an abrupt disruption of cerebral circulation. The intricate damage mechanism involves several factors, such as inflammatory response, disturbance of ion balance, loss of energy production, excessive reactive oxygen species and glutamate release, and finally, neuronal death. Stroke research is now carried out using several experimental models and potential therapeutics. Furthermore, studies are being conducted to address the shortcomings of clinical care. A great deal of research is being done on novel pharmacological drugs, mitochondria targeting compounds, and different approaches including brain cooling and new technologies. Still, there are many unanswered questions about disease modeling and treatment strategies. Before these new approaches may be used in therapeutic settings, they must first be tested on large animals, as most of them have been done on rodents. However, there are several limitations to large animal stroke models used for research. In this review, the damage mechanisms in acute ischemic stroke and experimental acute ischemic stroke models are addressed. The current treatment approaches and promising experimental methods such as mitochondrial transplantation, hydrogel-based interventions, and strategies like mitochondria encapsulation and chemical modification, are also examined in this work.