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1.
Pharmaceutics ; 16(4)2024 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-38675172

RESUMO

Cimicifuga racemosa (CR) extracts contain diverse constituents such as saponins. These saponins, which act as a defense against herbivores and pathogens also show promise in treating human conditions such as heart failure, pain, hypercholesterolemia, cancer, and inflammation. Some of these effects are mediated by activating AMP-dependent protein kinase (AMPK). Therefore, comprehensive screening for activating constituents in a CR extract is highly desirable. Employing machine learning (ML) techniques such as Deep Neural Networks (DNN), Logistic Regression Classification (LRC), and Random Forest Classification (RFC) with molecular fingerprint MACCS descriptors, 95 CR constituents were classified. Calibration involved 50 randomly chosen positive and negative controls. LRC achieved the highest overall test accuracy (90.2%), but DNN and RFC surpassed it in precision, sensitivity, specificity, and ROC AUC. All CR constituents were predicted as activators, except for three non-triterpene compounds. The validity of these classifications was supported by good calibration, with misclassifications ranging from 3% to 17% across the various models. High sensitivity (84.5-87.2%) and specificity (84.1-91.4%) suggest suitability for screening. The results demonstrate the potential of triterpene saponins and aglycones in activating AMP-dependent protein kinase (AMPK), providing the rationale for further clinical exploration of CR extracts in metabolic pathway-related conditions.

2.
Phytomedicine ; 100: 154060, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35338990

RESUMO

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.


Assuntos
Cimicifuga , Proteínas Quinases Ativadas por AMP , Estrogênios/farmacologia , Feminino , Fogachos/tratamento farmacológico , Temperatura Alta , Humanos , Menopausa , Fitoterapia , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico
3.
Viruses ; 14(1)2022 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-35062310

RESUMO

The coronavirus disease 2019 (COVID-19), caused by a novel coronavirus (SARS-CoV-2), has spread worldwide, affecting over 250 million people and resulting in over five million deaths. Antivirals that are effective are still limited. The antiviral activities of the Petasites hybdridus CO2 extract Ze 339 were previously reported. Thus, to assess the anti-SARS-CoV-2 activity of Ze 339 as well as isopetasin and neopetasin as major active compounds, a CPE and plaque reduction assay in Vero E6 cells was used for viral output. Antiviral effects were tested using the original virus (Wuhan) and the Delta variant of SARS-CoV-2. The antiviral drug remdesivir was used as control. Pre-treatment with Ze 339 in SARS-CoV-2-infected Vero E6 cells with either virus variant significantly inhibited virus replication with IC50 values of 0.10 and 0.40 µg/mL, respectively. The IC50 values obtained for isopetasin ranged between 0.37 and 0.88 µM for both virus variants, and that of remdesivir ranged between 1.53 and 2.37 µM. In conclusion, Ze 339 as well as the petasins potently inhibited SARS-CoV-2 replication in vitro of the Wuhan and Delta variants. Since time is of essence in finding effective treatments, clinical studies will have to demonstrate if Ze339 can become a therapeutic option to treat SARS-CoV-2 infections.


Assuntos
Antivirais/farmacologia , Extratos Vegetais/farmacologia , SARS-CoV-2/efeitos dos fármacos , Replicação Viral/efeitos dos fármacos , Monofosfato de Adenosina/análogos & derivados , Monofosfato de Adenosina/farmacologia , Alanina/análogos & derivados , Alanina/farmacologia , Animais , Antivirais/química , Dióxido de Carbono/química , Sobrevivência Celular/efeitos dos fármacos , Chlorocebus aethiops , Relação Dose-Resposta a Droga , Variação Genética , Petasites/química , Extratos Vegetais/química , SARS-CoV-2/genética , Sesquiterpenos/química , Sesquiterpenos/farmacologia , Células Vero
4.
Clin Case Rep ; 9(10): e04903, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34631086

RESUMO

Low-dose interferon-α 2a treatment may be considered as an alternative to cytoreductive therapy with hydroxyurea or regularly dosed interferon in high-risk polycythemia vera patients.

5.
Antioxidants (Basel) ; 10(9)2021 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-34573064

RESUMO

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.

6.
Phytomedicine ; 54: 66-76, 2019 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-30668384

RESUMO

BACKGROUND: Chronic stress, an important factor in the development of depressive disorders, leads to an increased formation of cortisol, which causes a hyperactivity of the hypothalamic-pituitary-adrenal (HPA) axis. In addition, cortisol mediates an adaptive effect on plasma membrane fluidity which may affect signal transduction of membrane-bound receptors and contribute to pathophysiological changes. METHODS: Membrane fluidity was measured by fluorescence anisotropy using DPH (1,6-diphenyl-1,3,5-hexatriene) and TMA-DPH (1-(4-(trimethylamino)phenyl)-6-phenylhexa-1,3,5-triene). Changes in cellular content of phosphatidylcholine species was determined by pulse-chase experiments using deuterated choline and mass spectrometry. Single molecule tracking was used to examine the lateral mobility of ß1-adrenoceptors and changes in cAMP formation were measured by ELISA. RESULTS: Chronic exposure (6 - 8 days) of C6 cells to cortisol dose-dependently decreased DPH and TMA-DPH fluorescence anisotropy, reflecting increased membrane fluidity. In contrast, cells pretreated with St. John's wort extract Ze117 showed increased DPH and TMA-DPH fluorescence anisotropy values, indicating a membrane rigidification effect which was mediated at least by the constituents hypericin, hyperforin, quercetin, amentoflavone and biapigenin. The observed membrane fluidizing effect of cortisol could be reversed by cotreatment with Ze117. The membrane rigidification of Ze117 was in line with the in parallel observed decrease in the phosphatidylcholine/phosphatidylethanolamine ratio determined in whole cell lipid extracts. Interestingly, pulse-chase experiments demonstrated, that Ze117 inhibited the incorporation of choline-D9 in phosphatidylcholine species with saturated or monounsaturated fatty acids compared to control cells, while the synthesis of phosphatidylcholine species with polyunsaturated fatty acids was not affected. C6 cells whose membranes have become more rigid by Ze117 showed altered lateral mobility of ß1-adrenoceptors as well as reduced cAMP formation after stimulation with the ß1-adrenoceptor agonist dobutamine. CONCLUSION: Obviously, the signaling of ß1-adrenoceptors depends on the nature of the membrane environment. It can therefore be assumed that Ze117 has a normalizing effect not only on the membrane fluidity of "stressed" cells, but also on lateral mobility and subsequently on the signal transduction of membrane-associated receptors.


Assuntos
Hypericum/química , Fluidez de Membrana/efeitos dos fármacos , Fosfatidiletanolaminas/metabolismo , Extratos Vegetais/farmacologia , Animais , Antracenos , Linhagem Celular Tumoral , Membrana Celular/química , Membrana Celular/efeitos dos fármacos , Glioblastoma/tratamento farmacológico , Glioblastoma/metabolismo , Hidrocortisona/farmacologia , Perileno/análogos & derivados , Perileno/farmacologia , Floroglucinol/análogos & derivados , Floroglucinol/farmacologia , Extratos Vegetais/química , Quercetina/farmacologia , Ratos , Receptores Adrenérgicos beta 1/metabolismo , Transdução de Sinais/efeitos dos fármacos , Terpenos/farmacologia
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