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The prevalence of age-related neurodegenerative diseases, such as Parkinson's disease (PD) and related disorders continues to grow worldwide. Increasing evidence links intracellular inclusions of misfolded alpha-synuclein (α-syn) aggregates, so-called Lewy bodies (LB) and Lewy neuritis, to the progressive pathology of PD and other synucleinopathies. Our previous findings established that α-syn oligomers induce S-nitrosylation and deregulation of the E3-ubiquitin ligase Parkin, leading to mitochondrial disturbances in neuronal cells. The accumulation of damaged mitochondria as a consequence, together with the release of mitochondrial-derived damage-associated molecular patterns (mtDAMPs) could activate the innate immune response and induce neuroinflammation ("mito-inflammation"), eventually accelerating neurodegeneration. However, the molecular pathways that transmit pro-inflammatory signals from damaged mitochondria are not well understood. One of the proposed pathways could be the cyclic GMP-AMP synthase (cGAS) - stimulator of interferon genes (STING) (cGAS-STING) pathway, which plays a pivotal role in modulating the innate immune response. It has recently been suggested that cGAS-STING deregulation may contribute to the development of various pathological conditions. Especially, its excessive engagement may lead to neuroinflammation and appear to be essential for the development of neurodegenerative brain diseases, including PD. However, the precise molecular mechanisms underlying cGAS-STING pathway activation in PD and other synucleinopathies are not fully understood. This review focuses on linking mitochondrial dysfunction to neuroinflammation in these disorders, particularly emphasizing the role of the cGAS-STING signaling. We propose the cGAS-STING pathway as a critical driver of inflammation in α-syn-dependent neurodegeneration and hypothesize that cGAS-STING-driven "mito-inflammation" may be one of the key mechanisms promoting the neurodegeneration in PD. Understanding the molecular mechanisms of α-syn-induced cGAS-STING-associated "mito-inflammation" in PD and related synucleinopathies may contribute to the identification of new targets for the treatment of these disorders.
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In a bioprospection for new antivirals, we tested nonribosomally biosynthesized polypeptide antibiotics in MDCK II cells for their actions on influenza A and B viruses (IAV/IBV). Only tolypin, a mixture of closely related 16-residue peptaibiotics from the fungus Tolypocladium inflatum IE 1897, showed promising activity. It was selected for further investigation and structural characterization by ultrahigh performance liquid chromatography coupled to high-resolution mass spectrometry (UHPLC-HR-MS/MS) and ultrahigh performance liquid chromatography coupled to in-source collision-induced dissociation tandem mass spectrometry (UHPLC-isCID-HR-MS/MS), revealing 12 partially co-eluting individual peptides that were fully sequenced. Since tolypin-related efrapeptins are potent inhibitors of F1/Fo-ATPase, we screened tolypin for its toxicity against MDCK II cells and larvae of the greater wax moth Galleria mellonella. We found that a nontoxic concentration of tolypin (1 µg/mL) reduced the titer of two IBV strains by 4-5 log values, and that of an H3N2 strain by 1-2 log values, but the H1N1pdm strain was not affected. The higher concentrations of tolypin were cytostatic to MDCK II cells, shifted their metabolism from oxidative phosphorylation to glycolysis, and induced paralysis in G. mellonella, supporting the inhibition of F1/Fo-ATPase as the mode of action. Our results lay the foundations for future work to investigate the interplay between viral replication and cellular energy metabolism, as well as the development of drugs that target host factors.
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Polypharmacy is common among patients with antithrombotic medication, giving rise to concerns about Drug-Related Problems (DRPs). Therefore, these patients would benefit from a Medication Review (MR) along with pharmacist counselling to reduce the risks accompanying polymedication. This prospective study presents a concept for MRs that are applicable in German community pharmacies and can efficiently support pharmacist counselling and improve the safety of drug therapy. As this is a major challenge in everyday pharmacy practice, we used a Decision Support System (DSS) to evaluate its ability to support the process of pharmacist-led MRs. The primary endpoint was the impact of a community pharmacist on the reduction of DRPs. We investigated the impact of the interventions resulting from MRs on patients taking at least one antithrombotic drug as part of their polymedication regimen. Secondary endpoints were the reduction in the number of patients with bleeding risks and the improvement of patients' Quality of Life (QoL) and therapy adherence. Furthermore, the DSS used in the study was controlled for correct data assessment and plausibility of data. We selected adult patients who were taking no less than three different medications for long-term treatment, at least one of which had to be an antithrombotic drug, and who were customers in one of eight selected pharmacies over a period of 6 months. Data from 87 patients were analyzed with DSS-support. A total of 234 DRPs were identified by the pharmacist (2.7 DRPs per patient). MR reduced DRPs by 43.2% which, resulting to a reduction of 1.2 DRPs per patient. The intervention also led to a significant improvement in the patients' QoL (assessed via EQ-5D-5L questionnaire; p < 0.001) and enhanced therapy adherence (assessed via A14 questionnaire; p < 0.001). The control of correct data assessment (with 93.8% concordance) and plausibility of data (with 91.7% concordance) of the DSS software were conducted by an external auditor. No significant effect was found for overall bleeding risk. The results of this study indicate that DSS-supported and structured MR conducted by pharmacists can contribute to a reduction in DRPs and significantly improve patient's QoL and adherence to treatment.
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Alzheimer's disease (AD) is prevalent around the world, yet our understanding of the disease is still very limited. Recent work suggests that the cornerstone of AD may include the inflammation that accompanies it. Failure of a normal pro-inflammatory immune response to resolve may lead to persistent central inflammation that contributes to unsuccessful clearance of amyloid-beta plaques as they form, neuronal death, and ultimately cognitive decline. Individual metabolic, and dietary (lipid) profiles can differentially regulate this inflammatory process with aging, obesity, poor diet, early life stress and other inflammatory factors contributing to a greater risk of developing AD. Here, we integrate evidence for the interface between these factors, and how they contribute to a pro-inflammatory brain milieu. In particular, we discuss the importance of appropriate polyunsaturated fatty acids (PUFA) in the diet for the metabolism of specialised pro-resolving mediators (SPMs); raising the possibility for dietary strategies to improve AD outlook.
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Envelhecimento , Doença de Alzheimer , Doença de Alzheimer/metabolismo , Doença de Alzheimer/fisiopatologia , Humanos , Envelhecimento/fisiologia , Envelhecimento/metabolismo , Animais , Doenças Neuroinflamatórias/imunologia , Doenças Neuroinflamatórias/metabolismo , Inflamação/metabolismo , Encéfalo/metabolismo , Encéfalo/fisiopatologiaRESUMO
Cimicifuga racemosa extracts (CREs) have gained well-established use for the treatment of menopausal symptoms such as hot flushes and excessive sweating, and weight gain. While the clinical effects of CREs have been well documented, the mechanisms underlying these effects are largely unknown. More recently, the metabolic effects of the CRE Ze 450 were demonstrated in cultured cells in vitro and in mouse models of obesity in vivo. At the molecular level, metabolic regulation, enhanced insulin sensitivity, and increased glucose uptake were linked to the activation of AMP-activated protein kinase (AMPK). Therefore, we tested the effects of Ze 450 on AMPK phosphorylation and thus activation in cells from different tissues, i.e., murine C2C12 myoblast cells, human HEPG2 liver cells, mouse HT22 neuronal cells, and in murine 3T3L1 adipocytes. Using a FRET-based HTRF-assay, we found that Ze 450 induced AMPK phosphorylation and the activation of this key enzyme of metabolic regulation in cells from various different tissues including C2C12 (muscle), HEPG2 (liver), HT22 (hippocampal), and 3T3-L1 (adipocyte) cells. In C2C12 muscle cells, enhanced AMPK activation was accompanied by reduced mitochondrial respiration and enhanced glucose uptake. Further, Ze 450 enhanced the resilience of the cells against oxidative death induced by ferroptosis inducers erastin or RSL3. Our findings suggest a general effect of Cimicifuga racemosa on AMPK activation in different tissues and across species. This may have a significant impact on expanded therapeutic applications of Ze 450, since AMPK activation and the related metabolic effects have been previously associated with anti-aging effects and the prevention of the metabolic syndrome.
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Inflammation involves the activation of innate immune cells and is believed to play an important role in the development and progression of both infectious and non-infectious diseases such as neurodegeneration, autoimmune diseases, pulmonary and cancer. Inflammation in the brain is marked by the upregulation of translocator protein (TSPO) in microglia. High TSPO levels are also found, for example, in macrophages in cases of rheumatoid arthritis and in malignant tumor cells compared to their relatively low physiological expression. The same applies for cyclooxgenase-2 (COX-2), which is constitutively expressed in the kidney, brain, thymus and gastrointestinal tract, but induced in microglia, macrophages and synoviocytes during inflammation. This puts TSPO and COX-2 in the spotlight as important targets for the diagnosis of inflammation. Imaging modalities, such as positron emission tomography and single-photon emission tomography, can be used to localize inflammatory processes and to track their progression over time. They could also enable the monitoring of the efficacy of therapy and predict its outcome. This review focuses on the current development of PET and SPECT tracers, not only for the detection of neuroinflammation, but also for emerging diagnostic measures in infectious and other non-infectious diseases such as rheumatic arthritis, cancer, cardiac inflammation and in lung diseases.
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Artrite Reumatoide , Doenças não Transmissíveis , Humanos , Ciclo-Oxigenase 2/metabolismo , Tomografia por Emissão de Pósitrons/métodos , Encéfalo/metabolismo , Biomarcadores/metabolismo , Artrite Reumatoide/diagnóstico por imagem , Artrite Reumatoide/patologia , Inflamação/metabolismo , Receptores de GABA/metabolismo , Proteínas de Transporte/metabolismoRESUMO
Specialized pro-resolving mediators (SPMs) and especially Resolvin E1 (RvE1) can actively terminate inflammation and promote healing during lung diseases such as acute respiratory distress syndrome (ARDS). Although ARDS primarily affects the lung, many ARDS patients also develop neurocognitive impairments. To investigate the connection between the lung and brain during ARDS and the therapeutic potential of SPMs and its derivatives, fat-1 mice were crossbred with RvE1 receptor knockout mice. ARDS was induced in these mice by intratracheal application of lipopolysaccharide (LPS, 10 µg). Mice were sacrificed at 0 h, 4 h, 24 h, 72 h, and 120 h post inflammation, and effects on the lung, liver, and brain were assessed by RT-PCR, multiplex, immunohistochemistry, Western blot, and LC-MS/MS. Protein and mRNA analyses of the lung, liver, and hypothalamus revealed LPS-induced lung inflammation increased inflammatory signaling in the hypothalamus despite low signaling in the periphery. Neutrophil recruitment in different brain structures was determined by immunohistochemical staining. Overall, we showed that immune cell trafficking to the brain contributed to immune-to-brain communication during ARDS rather than cytokines. Deficiency in RvE1 receptors and enhanced omega-3 polyunsaturated fatty acid levels (fat-1 mice) affect lung-brain interaction during ARDS by altering profiles of several inflammatory and lipid mediators and glial activity markers.
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Ácidos Graxos Ômega-3 , Síndrome do Desconforto Respiratório , Animais , Camundongos , Encéfalo , Cromatografia Líquida , Inflamação , Lipopolissacarídeos/toxicidade , Pulmão , Camundongos Knockout , Receptores do Leucotrieno B4 , Síndrome do Desconforto Respiratório/induzido quimicamente , Síndrome do Desconforto Respiratório/genética , Espectrometria de Massas em TandemRESUMO
Ferroptosis is a form of oxidative cell death that is characterized by enhanced lipid peroxidation and mitochondrial impairment. The enzymes acyl-CoA synthetase long-chain family member 4 (ACSL4) and lysophosphatidylcholine acyltransferase (LPCAT) play an essential role in the biosynthesis of polyunsaturated fatty acid (PUFA)-containing phospholipids, thereby providing the substrates for lipid peroxidation and promoting ferroptosis. To examine the impact of mitochondria in ACSL4/LPCAT2-driven ferroptosis, HEK293T cells overexpressing ACSL4 and LPCAT2 (OE) or empty vector controls (LV) were exposed to 1S, 3R-RSL3 (RSL3) for induction of ferroptosis. The ACSL4/LPCAT2 overexpression resulted in higher sensitivity against RSL3-induced cell death compared to LV-transfected controls. Moreover, mitochondrial parameters such as mitochondrial reactive oxygen species (ROS) formation, mitochondrial membrane potential, and mitochondrial respiration deteriorated in the OE cells, supporting the conclusion that mitochondria play a significant role in ACSL4/LPCAT2-driven ferroptosis. This was further confirmed through the protection of OE cells against RSL3-mediated cell death by the mitochondrial ROS scavenger mitoquinone (MitoQ), which exerted protection via antioxidative properties rather than through previously reported metabolic effects. Our findings implicate that mitochondrial ROS production and the accompanying organelle disintegration are essential for mediating oxidative cell death initiated through lipid peroxidation in ferroptosis.
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Background: Modern oral antineoplastic and immune-modulating drugs offer an array of therapeutic advantages, and yet pose challenges in daily use for patients, physicians and pharmacists. In contrast to intravenous administration, these drugs are not subject to direct medical control. Recently, we have seen a huge rise in sales of non-prescription over-the-counter (OTC) medicines via the internet without any advice from a healthcare professional. Objectives: The aim of this study was to investigate whether the risk of known potential drug-drug interactions between modern oral antineoplastic and immune-modulating drugs and OTC drugs differs between sales in traditional community pharmacies versus online pharmacies. Design: Real-life sales data from community and online pharmacies were used as basis for the analysis. Methods: We determined the most frequently purchased antineoplastic and immune-modulating drug-substances in 14 local community pharmacies within the Munich area, Germany and identified the OTC substance groups that could potentially cause interactions with oncological therapies. Using sales data from 11 local community pharmacies and three online pharmacies, we investigated whether OTC purchases differed between the two sales channels. Results: We identified 10 relevant OTC substance classes and detected significant variations in patients' preferred sales channels between the drug classes. Certain OTC drugs, which seem to be bought more often over the internet, pose risks during antineoplastic and immune-modulating therapy. Conclusion: Patients should therefore be proactively made aware of the corresponding risks in order not to jeopardize the activity of the antineoplastic and immune-modulating drugs and thus the success of their therapy.
Comparing Community and Online Pharmacies: Investigating Potential Interactions Between Cancer and Immune-Modulating Drugs with Over-the-Counter Medications, and the Importance of Patient Awareness and Healthcare Professional Guidance in Minimizing Adverse Effects and Maintaining Treatment Efficacy Modern anticancer and immune-modulating drugs have the advantage of often being taken orally, but they present other challenges in daily use. Unlike intravenously administered drugs, these are usually not administered by a physician but taken by the patient at home. In these cases, patients may be more likely to buy and take self-medicating drugs over-the-counter (OTC) without consulting a healthcare professional. This study aimed to investigate whether there is a different risk of drug interactions between cancer or immune-modulating drugs and OTC drugs when bought in a community pharmacy versus an online pharmacy. Therefore, we looked at the most common cancer and immune-modulating drugs purchased in 14 local community pharmacies in Munich and identified which OTC drugs could cause problems when used simultaneously. Additionally, we analyzed the sales data from 11 local and 3 online pharmacies to determine if people were more likely to buy different OTC drugs from the two types of pharmacies. As a result, this study showed 10 relevant OTC drug types that potentially cause problems and influence effectiveness when used with cancer or immune-modulating drugs. Furthermore, we observed that some of these OTC drugs were purchased more often online than in community pharmacies and thus are more distant from the control of a physician or pharmacist. It is therefore essential for patients to be aware of the risks associated with easily accessible OTC drugs in combination with their cancer or immune-modulating medication, as serious side effects or decreased efficacy may develop. Patients should remember to consult their doctor or pharmacist if there is any uncertainty about potential drug interactions. At the same time, healthcare professionals should proactively draw their patients' attention to these potential risks, especially when purchasing online.
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Ferroptosis is a type of oxidative cell death that can occur in neurodegenerative diseases and involves damage to mitochondria. Previous studies demonstrated that preventing mitochondrial dysfunction can rescue cells from ferroptotic cell death. However, the complexity of mitochondrial dysfunction and the timing of therapeutic interventions make it difficult to develop an effective treatment strategy against ferroptosis in neurodegeneration conditions. In this study, we explored the use of mitochondrial transplantation as a novel therapeutic approach for preventing ferroptotic neuronal cell death. Our data showed that isolated exogenous mitochondria were incorporated into both healthy and ferroptotic immortalized hippocampal HT-22 cells and primary cortical neurons (PCN). The mitochondrial incorporation was accompanied by increased metabolic activity and cell survival through attenuating lipid peroxidation and mitochondrial superoxide production. Further, the function of mitochondrial complexes I, III and V activities contributed to the neuroprotective activity of exogenous mitochondria. Similarly, we have also showed the internalization of exogenous mitochondria in mouse PCN; these internalized mitochondria were found to effectively preserve the neuronal networks when challenged with ferroptotic stimuli. The administration of exogenous mitochondria into the axonal compartment of a two-compartment microfluidic device induced mitochondrial transportation to the cell body, which prevented fragmentation of the neuronal network in ferroptotic PCN. These findings suggest that mitochondria transplantation may be a promising therapeutic approach for protecting neuronal cells from ferroptotic cell death.
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Ferroptose , Camundongos , Animais , Morte Celular , Mitocôndrias/metabolismo , Neurônios/metabolismo , Linhagem CelularRESUMO
Neural stem and progenitor cell (NSPC) transplants provide neuroprotection in models of acute brain injury, but the underlying mechanisms are not fully understood. Here, we provide evidence that caspase-dependent apoptotic cell death of NSPCs is required for sending survival signals to the injured brain. The secretome of dying NSPCs contains heat-stable proteins, which protect neurons against glutamate-induced toxicity and trophic factor withdrawal in vitro, and from ischemic brain damage in vivo. Our findings support a new concept suggesting a bystander effect of apoptotic NSPCs, which actively promote neuronal survival through the release of a protective "farewell" secretome. Similar protective effects by the secretome of apoptotic NSPC were also confirmed in human neural progenitor cells and neural stem cells but not in mouse embryonic fibroblasts (MEF) or human dopaminergic neurons, suggesting that the observed effects are cell type specific and exist for neural progenitor/stem cells across species.
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Efeito Espectador , Células-Tronco Neurais , Animais , Camundongos , Humanos , Fibroblastos , Encéfalo , Neurônios Dopaminérgicos , Ácido GlutâmicoRESUMO
In the central nervous system (CNS), insulin-like growth factor 1 (IGF-1) regulates myelination by oligodendrocyte (ODC) precursor cells and shows anti-apoptotic properties in neuronal cells in different in vitro and in vivo systems. Previous work also suggests that IGF-1 protects ODCs from cell death and enhances remyelination in models of toxin-induced and autoimmune demyelination. However, since evidence remains controversial, the therapeutic potential of IGF-1 in demyelinating CNS conditions is unclear. To finally shed light on the function of IGF1-signaling for ODCs, we deleted insulin-like growth factor 1 receptor (IGF1R) specifically in mature ODCs of the mouse. We found that ODC survival and myelin status were unaffected by the absence of IGF1R until 15 months of age, indicating that IGF-1 signaling does not play a major role in post-mitotic ODCs during homeostasis. Notably, the absence of IGF1R did neither affect ODC survival nor myelin status upon cuprizone intoxication or induction of experimental autoimmune encephalomyelitis (EAE), models for toxic and autoimmune demyelination, respectively. Surprisingly, however, the absence of IGF1R from ODCs protected against clinical neuroinflammation in the EAE model. Together, our data indicate that IGF-1 signaling is not required for the function and survival of mature ODCs in steady-state and disease.
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Encefalomielite Autoimune Experimental , Fator de Crescimento Insulin-Like I , Receptor IGF Tipo 1 , Animais , Camundongos , Cuprizona , Encefalomielite Autoimune Experimental/metabolismo , Fator de Crescimento Insulin-Like I/metabolismo , Camundongos Endogâmicos C57BL , Bainha de Mielina/metabolismo , Doenças Neuroinflamatórias , Oligodendroglia/metabolismo , Receptor IGF Tipo 1/metabolismoRESUMO
Cinnamic acid, ferulic acid, and the flavonoids quercetin and taxifolin (dihydroquercetin) are naturally occurring compounds found in plants. They are often referred to as polyphenols and are known, among others, for their pharmacological effects supporting health through the inhibition of aging processes and oxidative stress. To improve their bioavailability, pharmacological activities, and safety, the creation of novel flavonoid-phenolic acid hybrids is an area of active research. Previous work showed that such hybridization products of phenolic acids and flavonoids enhanced the resilience of neuronal cells against oxidative stress in vitro, and attenuated cognitive impairment in a mouse model of Alzheimer's disease (AD) in vivo. Notably, the therapeutic effects of the hybrid compounds we obtained were more pronounced than the protective activities of the respective individual components. The underlying mechanisms mediated by the flavonoid-phenolic acid hybrids, however, remained unclear and may differ from the signaling pathways activated by the originating structures of the respective individual phenolic acids or flavonoids. In this study, we characterized the effects of four previously described potent flavonoid-phenolic acid hybrids in models of oxidative cell death through ferroptosis. Ferroptosis is a type of iron-dependent regulated cell death characterized by lipid peroxidation and mitochondrial ROS generation and has been linked to neurodegenerative conditions. In models of ferroptosis induced by erastin or RSL3, we analyzed mitochondrial (lipid) peroxidation, mitochondrial membrane integrity, and Ca2+ regulation. Our results demonstrate the strong protective effects of the hybrid compounds against ROS formation in the cytosol and mitochondria. Importantly, these protective effects against ferroptosis were not mediated by radical scavenging activities of the phenolic hybrid compounds but through inhibition of mitochondrial complex I activity and reduced mitochondrial respiration. Our data highlight the effects of flavonoid-phenolic acid hybrids on mitochondrial metabolism and further important mitochondrial parameters that collectively determine the health and functionality of mitochondria with a high impact on the integrity and survival of the neuronal cells.
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This study addresses the eventual consequence of cytochrome c oxidase (CytOx) inhibition by ATP at high ATP/ADP ratio in isolated rat heart mitochondria. Earlier, it has been demonstrated that the mechanism of allosteric ATP inhibition of CytOx is one of the key regulations of mitochondrial functions. It is relevant that aiming to maintain a high ATP/ADP ratio for the measurement of CytOx activity effectuating the enzymatic inhibition as well as mitochondrial respiration, optimal concentration of mitochondria is critically important. Likewise, only at this concentration, were the differences in ΔΨm and ROS concentrations measured under various conditions significant. Moreover, when CytOx activity was inhibited in the presence of ATP, mitochondrial respiration and ΔΨm both remained static, while the ROS production was markedly decreased. Consubstantial results were found when the electron transport chain was inhibited by antimycin A, letting only CytOx remain functional to support the energy production. This seems to corroborate that the decrease in mitochondrial ROS production is solely the effect of ATP binding to CytOx which results in static respiration as well as membrane potential.
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Complexo IV da Cadeia de Transporte de Elétrons , Mitocôndrias Cardíacas , Difosfato de Adenosina/metabolismo , Trifosfato de Adenosina/metabolismo , Animais , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Mitocôndrias Cardíacas/metabolismo , Ratos , Espécies Reativas de Oxigênio/metabolismoRESUMO
BACKGROUND: Cimicifuga racemosa extracts (CRE) have obtained a "well-established use status" in the treatment of postmenopausal (i.e., climacteric) complaints, which predominantly include vasomotor symptoms such as hot flushes and sweating, as well as nervousness, irritability, and metabolic changes. Although characteristic postmenopausal complaints are known for a very long time and the beneficial effects of CRE on climacteric symptoms are well accepted, both the pathophysiology of postmenopausal symptoms and the mechanism of action of CREs are not yet fully understood. In particular, current hypotheses suggest that changes in the α-adrenergic and serotonergic signaling pathways secondary to estrogen depletion are responsible for the development of hot flushes. PURPOSE: Some of the symptoms associated with menopause cannot be explained by these hypotheses. Therefore, we attempted to extend our classic understanding of menopause by integrating of partly age-related metabolic impairments. METHODS: A comprehensive literature survey was performed using the PubMed database for articles published through September 2021. The following search terms were used: (cimicifuga OR AMPK) AND (hot flush* OR hot flash* OR menopaus* OR osteoporos* OR cancer OR antioxida* OR cardiovasc*). No limits were set with respect to language, and the references cited in the articles retrieved were used to identify additional publications. RESULTS: We found that menopause is a manifestation of the general aging process, with specific metabolic changes that aggravate menopausal symptoms, which are accelerated by estrogen depletion and associated neurotransmitter dysregulation. Cimicifuga extracts with their metabolic effects mitigate climacteric symptoms but may also modulate the aging process itself. Central to these effects are effects of CRE on the metabolic key regulator, the AMP-activated protein kinase (AMPK). CONCLUSIONS: As an extension of this effect dimension, other off-label indications may appear attractive in the sense of repurposing of this herbal treatment.
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Cimicifuga , Proteínas Quinases Ativadas por AMP , Estrogênios/farmacologia , Feminino , Fogachos/tratamento farmacológico , Temperatura Alta , Humanos , Menopausa , Fitoterapia , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêuticoRESUMO
PURPOSE: Previously, we have shown that CyPPA (cyclohexyl-[2-(3,5-dimethyl-pyrazol-1-yl)-6-methyl-pyrimidin-4-yl]-amine), a pharmacological small-conductance calcium-activated potassium (SK)-channel positive modulator, antagonizes lipopolysaccharide (LPS)-induced cytokine expression in microglial cells. Here, we aimed to test its therapeutic potential for brain-controlled sickness symptoms, brain inflammatory response during LPS-induced systemic inflammation, and peripheral metabolic pathways in mice. METHODS: Mice were pretreated with CyPPA (15 mg/kg IP) 24 hours before and simultaneously with LPS stimulation (2.5 mg/kg IP), and the sickness response was recorded by a telemetric system for 24 hours. A second cohort of mice were euthanized 2 hours after CyPPA or solvent treatment to assess underlying CyPPA-induced mechanisms. Brain, blood, and liver samples were analyzed for inflammatory mediators or nucleotide concentrations using immunohistochemistry, real-time PCR and Western blot, or HPLC. Moreover, we investigated CyPPA-induced changes of UCP1 expression in brown adipose tissue (BAT)-explant cultures. RESULTS: CyPPA treatment did not affect LPS-induced fever, anorexia, adipsia, or expression profiles of inflammatory mediators in the hypothalamus or plasma or microglial reactivity to LPS (CD11b staining and CD68 mRNA expression). However, CyPPA alone induced a rise in core body temperature linked to heat production via altered metabolic pathways like reduced levels of adenosine, increased protein content, and increased UCP1 expression in BAT-explant cultures, but no alteration in ATP/ADP concentrations in the liver. CyPPA treatment was accompanied by altered pathways, including NFκB signaling, in the hypothalamus and cortex, while circulating cytokines remained unaltered. CONCLUSION: Overall, while CyPPA has promise as a treatment strategy, in particular according to results from in vitro experiments, we did not reveal anti-inflammatory effects during severe LPS-induced systemic inflammation. Interestingly, we found that CyPPA alters metabolic pathways inducing short hyperthermia, most likely due to increased energy turnover in the liver and heat production in BAT.
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Many cell death pathways, including apoptosis, regulated necrosis, and ferroptosis, are relevant for neuronal cell death and share common mechanisms such as the formation of reactive oxygen species (ROS) and mitochondrial damage. Here, we present the role of the actin-regulating protein cofilin1 in regulating mitochondrial pathways in oxidative neuronal death. Cofilin1 deletion in neuronal HT22 cells exerted increased mitochondrial resilience, assessed by quantification of mitochondrial ROS production, mitochondrial membrane potential, and ATP levels. Further, cofilin1-deficient cells met their energy demand through enhanced glycolysis, whereas control cells were metabolically impaired when challenged by ferroptosis. Further, cofilin1 was confirmed as a key player in glutamate-mediated excitotoxicity and associated mitochondrial damage in primary cortical neurons. Using isolated mitochondria and recombinant cofilin1, we provide a further link to toxicity-related mitochondrial impairment mediated by oxidized cofilin1. Our data revealed that the detrimental impact of cofilin1 on mitochondria depends on the oxidation of cysteine residues at positions 139 and 147. Overall, our findings show that cofilin1 acts as a redox sensor in oxidative cell death pathways of ferroptosis, and also promotes glutamate excitotoxicity. Protective effects by cofilin1 inhibition are particularly attributed to preserved mitochondrial integrity and function. Thus, interfering with the oxidation and pathological activation of cofilin1 may offer an effective therapeutic strategy in neurodegenerative diseases.
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Cofilina 1/metabolismo , Mitocôndrias/patologia , Neurônios/patologia , Estresse Oxidativo , Animais , Morte Celular/efeitos dos fármacos , Linhagem Celular , Respiração Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Cofilina 1/deficiência , Regulação para Baixo/efeitos dos fármacos , Metabolismo Energético/efeitos dos fármacos , Ácido Glutâmico/toxicidade , Glicólise/efeitos dos fármacos , Humanos , Peroxidação de Lipídeos/efeitos dos fármacos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos , Mitocôndrias/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Neurotoxinas/toxicidade , Oxirredução/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Fosforilação/efeitos dos fármacos , Piperazinas/toxicidade , RNA Interferente Pequeno/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Proteínas Recombinantes/farmacologiaRESUMO
Recently, we reported that the Cimicifuga racemosa extract Ze 450 mediated protection from oxidative cell damage through a metabolic shift from oxidative phosphorylation to glycolysis. Here, we investigated the molecular mechanisms underlying the effects of Ze 450 against ferroptosis in neuronal cells, with a particular focus on mitochondria. The effects of Ze 450 on respiratory complex activity and hallmarks of ferroptosis were studied in isolated mitochondria and in cultured neuronal cells, respectively. In addition, Caenorhabditis elegans served as a model organism to study mitochondrial damage and longevity in vivo. We found that Ze 450 directly inhibited complex I activity in mitochondria and enhanced the metabolic shift towards glycolysis via cMyc and HIF1α regulation. The protective effects against ferroptosis were mediated independently of estrogen receptor activation and were distinct from effects exerted by metformin. In vivo, Ze 450 protected C. elegans from the mitochondrial toxin paraquat and promoted longevity in a dose-dependent manner. In conclusion, Ze 450 mediated a metabolic shift to glycolysis via direct effects on mitochondria and altered cell signaling, thereby promoting sustained cellular resilience to oxidative stress in vitro and in vivo.
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Blocking the interaction between the apoptosis-inducing factor (AIF) and cyclophilin A (CypA) by the AIF fragment AIF(370-394) is protective against glutamate-induced neuronal cell death and brain injury in mice. Starting from AIF(370-394), we report the generation of the disulfide-bridged and shorter variant AIF(381-389) and its structural characterization by nuclear magnetic resonance (NMR) in the free and CypA-bound state. AIF(381-389) in both the free and bound states assumes a ß-hairpin conformation similar to that of the fragment in the AIF protein and shows a highly reduced conformational flexibility. This peptide displays a similar in vitro affinity for CypA, an improved antiapoptotic activity in cells and an enhanced proteolytic stability compared to the parent peptide. The NMR-based 3D model of the AIF(381-389)/CypA complex provides a better understanding of the binding hot spots on both the peptide and the protein and can be exploited to design AIF/CypA inhibitors with improved pharmacokinetic and pharmacodynamics features.