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1.
Arch Biochem Biophys ; 754: 109952, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38432565

RESUMO

Hedgehog (Hh) signaling plays a significant role in embryogenesis and several physiological processes, such as wound healing and organ homeostasis. In a pathological setting, it is associated with oncogenesis and is responsible for disease progression and poor clinical outcomes. Hedgehog signaling mediates downstream actions via Glioma Associated Oncogene Homolog (GLI) transcription factors. Inhibiting Hh signaling is an important oncological strategy in which inhibitors of the ligands SMO or GLI have been looked at. This review briefly narrates the Hh ligands, signal transduction, the target genes involved and comprehensively describes the numerous inhibitors that have been evaluated for use in various neoplastic settings.


Assuntos
Proteínas Hedgehog , Neoplasias , Humanos , Transdução de Sinais/genética , Alcaloides de Veratrum , Neoplasias/tratamento farmacológico
2.
Virus Res ; 339: 199260, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-37923169

RESUMO

Porcine epidemic diarrhea (PED) is a contagious intestinal disease caused by α-coronavirus porcine epidemic diarrhea virus (PEDV). At present, no effective vaccine is available to prevent the disease. Therefore, research for novel antivirals is important. This study aimed to identify the antiviral mechanism of Veratramine (VAM), which actively inhibits PEDV replication with a 50 % inhibitory concentration (IC50) of ∼5 µM. Upon VAM treatment, both PEDV-nucleocapsid (N) protein level and virus titer decreased significantly. The time-of-addition assay results showed that VAM could inhibit PEDV replication by blocking viral entry. Importantly, VAM could inhibit PEDV-induced phosphatidylinositol 3-kinase/protein kinase B (PI3K/Akt) activity and further suppress micropinocytosis, which is required for PEDV entry. In addition, PI3K inhibitor LY294002 showed anti-PEDV activity by blocking viral entry as well. Taken together, VAM possessed anti-PEDV properties against the entry stage of PEDV by inhibiting the macropinocytosis pathway by suppressing the PI3K/Akt pathway. VAM could be considered as a lead compound for the development of anti-PEDV drugs and may be used during the viral entry stage of PEDV infection.


Assuntos
Infecções por Coronavirus , Fosfatidilinositol 3-Quinases , Vírus da Diarreia Epidêmica Suína , Doenças dos Suínos , Alcaloides de Veratrum , Internalização do Vírus , Animais , Chlorocebus aethiops , Infecções por Coronavirus/tratamento farmacológico , Infecções por Coronavirus/veterinária , Fosfatidilinositol 3-Quinases/metabolismo , Vírus da Diarreia Epidêmica Suína/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Suínos , Doenças dos Suínos/tratamento farmacológico , Alcaloides de Veratrum/metabolismo , Alcaloides de Veratrum/farmacologia , Células Vero , Internalização do Vírus/efeitos dos fármacos
3.
J Am Chem Soc ; 145(40): 21760-21765, 2023 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-37782691

RESUMO

A concise and enantioselective total synthesis of the Veratrum alkaloid cyclopamine is disclosed. This highly convergent synthesis with a 16-step longest linear sequence (LLS) was enabled by a de novo synthesis of the trans-6,5-heterobicycle via a strain-inducing halocyclization process, a key Tsuji-Trost cyclization to construct the fully substituted, spirocyclic THF motif with exquisite diastereocontrol, and a late-stage ring-closing metathesis (RCM) reaction to forge the central tetrasubstituted olefin.


Assuntos
Alcenos , Alcaloides de Veratrum , Ciclização , Estereoisomerismo
4.
Int J Mol Sci ; 24(18)2023 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-37762166

RESUMO

Respiratory syncytial virus (RSV) RNA synthesis takes place in cytoplasmic viral factories also called inclusion bodies (IBs), which are membrane-less organelles concentrating the viral RNA polymerase complex. The assembly of IBs is driven by liquid-liquid phase separation promoted by interactions between the viral nucleoprotein N and the phosphoprotein P. We recently demonstrated that cyclopamine (CPM) inhibits RSV multiplication by disorganizing and hardening IBs. Although a single mutation in the viral transcription factor M2-1 induced resistance to CPM, the mechanism of action of CPM still remains to be characterized. Here, using FRAP experiments on reconstituted pseudo-IBs both in cellula and in vitro, we first demonstrated that CPM activity depends on the presence of M2-1 together with N and P. We showed that CPM impairs the competition between P and RNA binding to M2-1. As mutations on both P and M2-1 induced resistance against CPM activity, we suggest that CPM may affect the dynamics of the M2-1-P interaction, thereby affecting the relative mobility of the proteins contained in RSV IBs. Overall, our results reveal that stabilizing viral protein-protein interactions is an attractive new antiviral approach. They pave the way for the rational chemical optimization of new specific anti-RSV molecules.


Assuntos
RNA , Vírus Sincicial Respiratório Humano , Alcaloides de Veratrum , Corpos de Inclusão
5.
Phytomedicine ; 120: 155033, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37647672

RESUMO

BACKGROUND: Hypertension is a serious global public health issue. Blood pressure (BP) is still not effectively controlled in about 20 - 30% of hypertensive patients. Therefore, it is imperative to develop new treatments for hypertension. Veratrum alkaloids were once used for the clinical treatment of hypertension, the mechanism of which is still unclear. It was gradually phased out due to adverse reactions. PURPOSE: This study aimed to investigate the short-term and long-term hypotensive profiles of different components of Veratrum alkaloids in spontaneously hypertensive rats (SHRs) to unveil their mechanisms of action. RESULTS: Total Veratrum alkaloid (V), component A (A), and veratramine (M) quickly decreased BP within 30 min of treatment, reduced renal and cardiovascular damage, and improved relevant biochemical indicators (nitric oxide [NO], endothelin-1 [ET-1], angiotensin II [Ang II)], noradrenaline [NE], etc) in SHRs to delay stroke occurrence. Thereinto, A exhibited excellent protective effects in cardiovascular disease. The metabolomic profiles of SHRs treated with V, A, and M were significantly different from those of SHRs treated with vehicle. Thirteen metabolites were identified as potential pharmacodynamic biomarkers. Through Kyoto Encyclopedia of Genes and Genomes analysis, V, A, and M-induced hypotension was mainly related to alterations in nicotinate and nicotinamide metabolism, GABAergic synapses, linoleic acid metabolism, ketone body synthesis and degradation, arginine and proline metabolism, and urea cycle, of which nicotinate and nicotinamide metabolism was the key metabolic pathway to relieve hypertension. CONCLUSION: This work shows that A is an effective and promising antihypertensive agent for hypertension treatment to reduce BP and hypertensive target organ damage, which is mainly mediated through modulating nicotinate and nicotinamide metabolism, RAS, and NO-ET homeostasis.


Assuntos
Hipertensão , Niacina , Humanos , Animais , Ratos , Anti-Hipertensivos/farmacologia , Alcaloides de Veratrum , Hipertensão/tratamento farmacológico , Análise de Dados , Niacinamida
6.
Sci Rep ; 13(1): 8198, 2023 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-37211560

RESUMO

Veratrum (Melanthiaceae; Liliales) is a genus of perennial herbs known for the production of unique bioactive steroidal alkaloids. However, the biosynthesis of these compounds is incompletely understood because many of the downstream enzymatic steps have yet to be resolved. RNA-Seq is a powerful method that can be used to identify candidate genes involved in metabolic pathways by comparing the transcriptomes of metabolically active tissues to controls lacking the pathway of interest. The root and leaf transcriptomes of wild Veratrum maackii and Veratrum nigrum plants were sequenced and 437,820 clean reads were assembled into 203,912 unigenes, 47.67% of which were annotated. We identified 235 differentially expressed unigenes potentially involved in the synthesis of steroidal alkaloids. Twenty unigenes, including new candidate cytochrome P450 monooxygenases and transcription factors, were selected for validation by quantitative real-time PCR. Most candidate genes were expressed at higher levels in roots than leaves but showed a consistent profile across both species. Among the 20 unigenes putatively involved in the synthesis of steroidal alkaloids, 14 were already known. We identified three new CYP450 candidates (CYP76A2, CYP76B6 and CYP76AH1) and three new transcription factor candidates (ERF1A, bHLH13 and bHLH66). We propose that ERF1A, CYP90G1-1 and CYP76AH1 are specifically involved in the key steps of steroidal alkaloid biosynthesis in V. maackii roots. Our data represent the first cross-species analysis of steroidal alkaloid biosynthesis in the genus Veratrum and indicate that the metabolic properties of V. maackii and V. nigrum are broadly conserved despite their distinct alkaloid profiles.


Assuntos
Alcaloides , Veratrum , Veratrum/genética , Transcriptoma , Alcaloides/genética , Perfilação da Expressão Gênica , Alcaloides de Veratrum , Esteroides , Sistema Enzimático do Citocromo P-450/genética
7.
Bioorg Med Chem ; 84: 117265, 2023 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-37001245

RESUMO

Cyclopamine (1), the teratogenic steroidal alkaloid isolated from corn lily (Veratrum californicum), has recently gained renewed interest due to its anticancer potential, that has been translated into the FDA approval of three Hedgehog (Hh) pathway inhibiting antitumor drugs. A chemical analysis of mother liquors obtained from crystallization of cyclopamine, extracted from roots and rhizomes of V. californicum, resulted in the isolation of two unprecedented cyclopamine analogues, 18-hydroxycyclopamine (2) and 24R-hydroxycyclopamine (3), the first compounds of this class to show modifications on rings D-F. The stereostructures of these new natural compounds have been established based on a detailed MS and 1D/2D NMR investigation. The isolated compounds were evaluated with the dual-luciferase bioassay for their inhibition of the hedgehog pathway in comparison to cyclopamine, providing new insights into the structure-activity relationships for this class of compounds.


Assuntos
Alcaloides , Veratrum , Veratrum/química , Proteínas Hedgehog , Alcaloides de Veratrum/farmacologia , Alcaloides de Veratrum/química
8.
Fitoterapia ; 166: 105464, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36848963

RESUMO

Three new steroidal alkaloids, veratrasines A - C (1-3), along with ten known analogues (4-13) were isolated from the roots of Veratrum stenophyllum. Their structures were elucidated by NMR and HRESIMS data and comparison with the reported data in the literatures. A plausible biosynthetic pathway for 1 and 2 were proposed. Compounds 1, 3, and 8 showed moderate cytotoxic activity against MHCC97H and H1299 cell lines.


Assuntos
Alcaloides , Veratrum , Veratrum/química , Estrutura Molecular , Raízes de Plantas , Esteroides , Alcaloides de Veratrum/química
9.
Toxins (Basel) ; 16(1)2023 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-38276530

RESUMO

The injudicious and excessive use of synthetic pesticides has deleterious effects on humans, ecosystems, and biodiversity. As an alternative to traditional crop-protection methods, botanical pesticides are gaining importance. In this research endeavor, we examined the contact toxicity, knockdown time, lethal time, and toxicity horizontal transmission of three natural pesticides from plants (azadirachtin, celangulin, and veratramine) on red imported fire ants (RIFA; Solenopsis invicta). Our research findings indicated that azadirachtin and celangulin exhibited relatively high toxicity, with median lethal dose (LD50) values of 0.200 and 0.046 ng/ant, respectively, whereas veratramine exhibited an LD50 value of 544.610 ng/ant for large workers of S. invicta at 24 h post-treatment. Upon treatment with 0.125 mg/L, the (median lethal time) LT50 values of azadirachtin and celangulin were determined to be 60.410 and 9.905 h, respectively. For veratramine, an LT50 value of 46.967 h was achieved after being tested with 200 mg/L. Remarkably, azadirachtin and celangulin were found to exhibit high horizontal transfer among RIFA, with high secondary mortality (100%) and tertiary mortalities (>61%) after 48 h of treatment with 250 mg/L, as well as with their dust formulations for 72 h. However, veratramine did not exhibit significant toxicity or horizontal transfer effects on RIFA, even at high concentrations. These findings suggest that azadirachtin and celangulin are likely to have a highly prominent potential in the management of S. invicta.


Assuntos
Formigas , Inseticidas , Limoninas , Praguicidas , Alcaloides de Veratrum , Animais , Humanos , 60601 , Ecossistema , Inseticidas/toxicidade
10.
Clin Toxicol (Phila) ; 60(12): 1309-1317, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36301078

RESUMO

INTRODUCTION: The Veratrum genus is composed of plants containing a diverse set of steroidal alkaloids. Veratrum plant material has been utilized for centuries as herbal medicines, however the alkaloids have such a low therapeutic index that they are not used in modern medicine. Here we report an incident of inadvertent ingestion of V. parviflorum by hikers in Georgia that allowed detection, and in several instances identification of alkaloids from the plant, and correlated their presence within patient blood and breast milk specimens. CASE HISTORY: Eight patients, three male and five female, presented in the spring of 2020 and 2021 with symptoms requiring emergent medical attention after ingestion of Veratrum parviflorum. All patients believed the plants to be a local native species of wild leek, Allium tricoccum, locally known as ramps. Plants were identified using photographs as well as fresh and cooked plant material provided by patients, in consultation with botanists at the University of Georgia Herbarium. Written consent was obtained from all patients for collection of blood and breast milk specimens for laboratory identification of Veratrum alkaloids. METHODS: V. parviflorum plant material, and patient serum and breast milk were analyzed by high performance liquid chromatography-quadrupole time-of-flight mass spectrometry (HPLC-QTOF) to identify steroidal alkaloids. RESULTS: The V. parviflorum extract was confirmed to contain cyclopamine, veratramine, jervine, and muldamine. Two out of the eight patients had detectable concentrations of Veratrum alkaloids. Of the alkaloids identified in the plant, cyclopamine and jervine were detected within patient serum, and cyclopamine and veratramine were observed to be present in breast milk. DISCUSSION: Toxicity resulting from Veratrum steroidal alkaloids has primarily been reported from V. album and V. viride. This is the second report of V. parviflorum poisoning. The present work reports for the first time the presence of muldamine and jervine within V. parviflorum. This work provides the first instance of identification of Veratrum alkaloids in breast milk. Thus, the findings presented herein add to literature record causative agents contributing to the toxicity of V. parviflorum when ingested and potential for secondary poisoning through breastfeeding. CONCLUSION: V. parviflorum toxicity was observed to cause nausea, vomiting, hypotension, bradycardia, abdominal pain, light-headedness, blurred vision, and tingling in the arms. Patients experiencing mild symptoms improved with supportive care, IV fluids, and antiemetics, but hemodynamically unstable patients required atropine and vasopressors. This study demonstrated that more lipophilic Veratrum alkaloids can be passed along in breast milk, which suggests additional precautions may be critical to limit further poisonings.


Assuntos
Alcaloides , Intoxicação por Plantas , Veratrum , Feminino , Humanos , Leite Humano , Alcaloides de Veratrum , Intoxicação por Plantas/tratamento farmacológico
11.
Toxins (Basel) ; 14(7)2022 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-35878228

RESUMO

Jervine, protoveratrine A (proA), and protoveratrine B (proB) are Veratrum alkaloids that are presented in some remedies obtained from Veratrum lobelianum, such as Veratrum aqua. This paper reports on a single-center pilot cardiotoxic mechanism study of jervine, proA, and proB in case series. The molecular aspects were studied via molecular dynamic simulation, molecular docking with cardiac sodium channel NaV1.5, and machine learning-based structure-activity relationship modeling. HPLC-MS/MS method in combination with clinical events were used to analyze Veratrum alkaloid cardiotoxicity in patients. Jervine demonstrates the highest docking score (-10.8 kcal/mol), logP value (4.188), and pKa value (9.64) compared with proA and proB. Also, this compound is characterized by the lowest calculated IC50. In general, all three analyzed alkaloids show the affinity to NaV1.5 that highly likely results in cardiotoxic action. The clinical data of seven cases of intoxication by Veratrum aqua confirms the results of molecular modeling. Patients exhibited nausea, muscle weakness, bradycardia, and arterial hypotension. The association between alkaloid concentrations in blood and urine and severity of patient condition is described. These experiments, while primary, confirmed that jervine, proA, and proB contribute to cardiotoxicity by NaV1.5 inhibition.


Assuntos
Alcaloides , Veratrum , Alcaloides/toxicidade , Cardiotoxicidade , Humanos , Simulação de Acoplamento Molecular , Projetos Piloto , Espectrometria de Massas em Tandem , Alcaloides de Veratrum/farmacologia
12.
Comput Math Methods Med ; 2022: 8289548, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35785141

RESUMO

Background: Chinese Materia Medica and Jiangsu New Medical College record that Radix Veratri root is Liliaceae Veratrum taliense Loses. f. and the root of Veratrum stenophyllum Diels. According to traditional Chinese medicine (TCM) example, Radix Veratri is a Liliaceae plant Veratrum taliense. Another literature pointed out that the aliases of Veratrum taliense and Veratrum angustifolia are both Radix Veratri, and their effects are basically the same. The main active ingredient of Veratrum is veratramine, of which veratramine and Jervine are higher in content, reaching 24.60% and 21.28% of the total alkaloids, respectively. Veratrum alkaloids are both toxic and effective ingredients. In addition to its good clinical efficacy, attention should also be paid to its pharmacokinetic characteristics in vivo. It is particularly important to study the pharmacokinetic characteristics of veratramine and Jervine in vivo. Objective: The goal of this study was to develop a simple and effective method for measuring veratramine and Jervine in rat plasma at the same time. This method was used to study the pharmacokinetic characteristics of veratramine and Jervine in the alcohol extract of Radix Veratri in rats, to provide a reasonable basis for the clinical use of Radix Veratri. Methods: Eighteen SD rats were randomly assigned into three groups, half male and half female, and were given 0.04 g/kg, 0.08g/kg, and 0.16 g/kg Radix Veratri alcohol extract, respectively. Blood samples were collected at different time points and were analyzed by LC-MS/MS after protein precipitation. Bullatine was set as the internal standard; the plasma samples were extracted with ethyl acetate. After the sample was processed, acetonitrile-10 mM ammonium acetate, whose pH was adjusted to 8.8 with ammonia water, was taken as the mobile phase. Veratramine quantitative ion pair was 410.1⟶295.1m/z, Jervine quantitative ion pair was 426.2⟶114.1m/z, and Bullatine B (IS) quantitative ion pair was 438.2⟶420.1m/z. In the positive ion mode, the multireaction monitoring (MRM) mode was used to determine the blood concentration of veratramine and Jervine. DAS 3.3.0 was used to calculate the relevant pharmacokinetic parameters. Results: Veratramine had a good linear relationship in the concentration range of 0.0745~18.2 ng/mL, and that of Jervine was 1.11~108 ng/mL. The correlation coefficient r of three consecutive batches of the standard curve was greater than 0.995. Veratramine's lower quantification limit was 0.745 ng/mL, Jervine's was 1.11 ng/mL, and precision and accuracy were both less than 15%. The accuracy of veratramine was between 88.96% and 101.85%, and the accuracy of Jervine was between 92.96% and 104.50%. This method was adopted for the pharmacokinetic study of alcohol extracts of Radix Veratri. The results showed that only C max of veratramine female rats did not show linear kinetic characteristics in the dose range of Radix Veratri alcohol extract from 0.04 g/kg to 0.16 g/kg. For AUC0-t and C max of veratramine and Jervine, it could not determine whether the Radix Veratri alcohol extract showed linear kinetic characteristics within the dosage range of 0.04 g/kg~0.16 g/kg. Veratramine and Jervine showed obvious gender differences in the absorption and elimination stages. The absorption rate of veratramine and Jervine by male mice was about 10 times higher than that of female mice, and the elimination rate of male mice is about 20 times lower than that of female mice. It was suggested that the clinical application of the steroidal alkaloids veratramine and Jervine in Radix Veratri required rational use of drugs based on gender. Conclusion: An LC-MS/MS analysis method suitable for the pharmacokinetic study of veratramine and Jervine in Radix Veratri in SD rats was established to provide a basis for in vivo pharmacokinetic studies. The pharmacokinetic characteristics of veratramine and Jervine in the alcohol extract of Radix Veratri were significantly different in female and male rats. During the clinical use of Radix Veratri, it should pay close attention to the obvious gender differences that may occur after the medication.


Assuntos
Alcaloides , Veratrum , Animais , Cromatografia Líquida , Feminino , Humanos , Masculino , Camundongos , Extratos Vegetais , Ratos , Ratos Sprague-Dawley , Espectrometria de Massas em Tandem , Veratrum/química , Alcaloides de Veratrum/química , Alcaloides de Veratrum/farmacocinética
13.
Int J Mol Med ; 49(5)2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35266008

RESUMO

Clear cell renal cell carcinoma (ccRCC) is the most common and aggressive subtype of kidney cancer, with high mortality rates worldwide. The sonic hedgehog (SHH) molecular cascade is altered in various malignancies in tumorigenesis, and several SHH pathway inhibitors have been considered as potential anticancer drugs. The aim of the present study was to determine the expression profile of SHH signaling components and their target genes in ccRCC. Additionally, the present study examined the effects of SHH pathway inhibitory drugs (RU­SKI43, cyclopamine and GLI­antagonist 61) on cell viability, cell cycle progression, expression levels of SHH target genes and migration ability in 786­O, ACHN and HK2 cells. The study also included paired tumor and normal samples from 62 patients with ccRCC. The mRNA levels in clinical samples and cell lines were measured via reverse transcription­quantitative PCR. Cell viability was examined using a sulforhodamine B assay. Flow cytometry was used to investigate cell cycle progression and the migratory rate of cells was assessed using a wound healing assay. High mRNA levels of SHH, smoothened (SMO), glioma­associated zinc finger protein (GLI)1­3, BCL2 apoptosis regulator (BCL2), MYC proto­oncogene (MYC), vascular endothelial growth factor A (VEGFA) and cyclin D1 (CCND1) were observed in the tumor tissues, especially in early ccRCC, according to the TNM stage or World Health Organization/International Society of Urological Pathology (ISUP) grade. High expression levels of VEGFA, as well as low CCND1 mRNA expression, were associated with short overall survival, and increased VEGFA expression was an independent prognostic factor of a poor outcome in patients with advanced ISUP grade (Cox hazard ratio test). Cyclopamine treatment was found to arrest 786­O cells in the G2/M phase and decreased the expression levels of GLI1, BCL2, VEGFA and CCND1. RU­SKI43 inhibited cell migration and decreased the expression levels of BCL2, MYC and CCND1 in ACHN cells. Overall, the results of the present study suggested that SHH signaling may be involved in the early development of ccRCC, and the expression levels of CCND1 and VEGFA may serve as prognostic factors of this disease. Cyclopamine and RU­SKI43 appear to be potential anti­renal cell carcinoma drugs; however, this hypothesis requires verification by further in vivo studies.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Carcinoma de Células Renais/genética , Proteínas Hedgehog/genética , Proteínas Hedgehog/metabolismo , Humanos , Neoplasias Renais/genética , Fator A de Crescimento do Endotélio Vascular , Alcaloides de Veratrum/farmacologia , Proteína GLI1 em Dedos de Zinco/genética
14.
Life Sci ; 288: 120170, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34826438

RESUMO

AIMS: Antitumor effects of veratramine in prostate and liver cancers has been investigated, but it is still unclear whether veratramine can be used as an effective therapeutic agent for glioma. The aim of this study was to evaluate the potential pharmacological mechanism of veratramine in glioma. MAIN METHODS: Using four types of human glioblastoma cell lines, including A172, HS-683, T98G, and U-373-MG the dose-dependent antitumor effect of veratramine was evaluated. The cytotoxicity and cell proliferation were examined by CCK-8, and cell proliferation was further confirmed by anchorage-independent colony formation assay. The cell cycle distribution and apoptotic rate was assessed by flow cytometry, and apoptosis was further evaluated by apoptosis assay. The migration and invasiveness capacity were analyzed by using transwell. Protein and mRNA levels of related factors were determined by western blotting and RT-qPCR, respectively. KEY FINDINGS: Veratramine markedly induced apoptosis, suppressed the cell proliferation via the cell cycle G0/G1 phase arrest, and reduced the capacity for the migration and invasion in human glioblastoma multiforme cell lines. Moreover, veratramine was sufficient to affect the phosphatidylinositol-3-kinase/serine-threonine kinase/mechanistic target of rapamycin signaling pathway and its downstream Mdm2/p53/p21 pathway in human glioblastoma cell lines. SIGNIFICANCE: Antitumor effects of veratramine in suppression of glioma progression was mediated by the regulation of PI3K/Akt/mTOR and Mdm2/p53/p21 signaling pathway.


Assuntos
Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Glioblastoma/tratamento farmacológico , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Alcaloides de Veratrum/farmacologia , Apoptose , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Ciclo Celular , Movimento Celular , Proliferação de Células , Inibidor de Quinase Dependente de Ciclina p21/genética , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Glioblastoma/genética , Glioblastoma/metabolismo , Glioblastoma/patologia , Humanos , Invasividade Neoplásica , Fosfatidilinositol 3-Quinases/genética , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-mdm2/genética , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Serina-Treonina Quinases TOR/genética , Células Tumorais Cultivadas , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo
15.
J Anal Toxicol ; 46(1): e42-e47, 2022 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-33559680

RESUMO

Veratrum poisonings are described in the toxicology literature as multiple Veratrum species grow in different parts of the Northern Hemisphere and are occasionally ingested by mistake. Veratrum toxicity is attributed to the steroidal alkaloids contained in all parts of the plant. In Russia, Veratrum poisonings are more common since there is an over-the-counter Veratrum lobelianum-based tincture, Veratrum Aqua (VA), which is topically used for the treatment of lice infestation. Despite its toxicity, VA is misused in traditional medicine as a remedy for alcohol use disorder. We describe four cases of VA poisoning that occurred in Moscow, Russia. Three main V. lobelianum alkaloids (jervine, protoveratrine A (proA) and protoveratrine B) were determined in patient plasma and urine samples using liquid chromatography-tandem mass spectrometry (LC-MS-MS). Here, we describe a novel validated LC-MS-MS method for jervine and proA quantification. A simple and rapid liquid-liquid extraction with methyl tert-butyl ether was utilized for analyte extraction. Chromatographic separation was achieved using a Poroshell 120 EC-C18 column, and the total run time was 14 min. The lower limit of quantification was 0.1 ng/mL for jervine and proA in both plasma and urine. Biological samples were obtained upon hospital admission and during treatment, thus enabling to get a better understanding of the alkaloid elimination profile. Upon admission, plasma concentrations of jervine (concentration range: 0.10-5.01 ng/mL) prevailed over proA (concentration range: 0-0.67 ng/mL). At this time, proA already reached maximum concentrations in urine (concentration range: 0.15-37.70 ng/mL). Maximum concentrations of jervine in urine were observed 24 h after admission (concentration range: 0.10-9.55 ng/mL). In all cases, plasma concentrations of Veratrum alkaloids correlated with condition severity. Since none of the patients confirmed VA intake, instrumental analysis was the basis for the definitive diagnosis of VA poisoning.


Assuntos
Alcaloides , Veratrum , Cromatografia Líquida , Humanos , Espectrometria de Massas , Alcaloides de Veratrum
16.
Neurol Res ; 44(4): 318-330, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34592910

RESUMO

OBJECTIVE: Ischemic stroke is a major cause of death in the global population, with a high disability and mortality rate. Lack of regenerative ability is considered to be the fundamental cause. This study aims to determine the effect of Shh pathway, which mediates regenerative signaling in response to CNS injury, on myelin repair and Olig1 expression in focal ischemic lesions in the rat. METHODS: A model of middle cerebral artery occlusion (MCAO) was established using the intraluminal suture method where the middle cerebral artery (MCA) was restricted for 120 min. Cyclopamine, a specific inhibitor of Shh, or saline was administered 12h after MCAO surgery and lasted for 7d. After MCA occlusion, male Sprague-Dawley rats were randomly allocated to cyclopamine- or saline-treated groups. A group of no-injection animals after MCAO were used as control. The Shh signaling pathway, myelinogenesis-related factor MBP and Olig1 were tested using immunohistochemistry and RT-PCR assay. RESULTS: The levels of Shh and its component Gli1 were elevated from 1d up to 14d following ischemia, indicating that the Shh-Gli1 axis was broadly reactivated. Treatment with cyclopamine can partially block the Shh signaling pathway, prevent myelin repair, and decrease the Olig1 expression following ischemic stroke. CONCLUSION: That blockade of Shh signaling concurrently with the creation of a lesion aggravated ischemic myelin damage, probably via its downstream effects on Olig1 transcription. Shh plays a contributory role during regeneration in the CNS, thereby providing promising new therapeutic strategies to assist in recovery from ischemic stroke.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Proteínas Hedgehog/metabolismo , Infarto da Artéria Cerebral Média/metabolismo , Regeneração Nervosa/fisiologia , Proteínas do Tecido Nervoso/metabolismo , Alcaloides de Veratrum/farmacologia , Proteína GLI1 em Dedos de Zinco/metabolismo , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/efeitos dos fármacos , Modelos Animais de Doenças , Proteínas Hedgehog/antagonistas & inibidores , Proteínas Hedgehog/efeitos dos fármacos , Masculino , Regeneração Nervosa/efeitos dos fármacos , Proteínas do Tecido Nervoso/efeitos dos fármacos , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Proteína GLI1 em Dedos de Zinco/efeitos dos fármacos
17.
Int J Mol Sci ; 22(19)2021 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-34639065

RESUMO

BACKGROUND: Basal cell carcinoma is one of the most common types of non-melanoma skin cancers, which can be locally destructive despite low-rate metastasis. Surgery is the treatment of choice, but it lacks of efficacy on advanced cases. Hedgehog pathway inhibitors are a class of drugs providing a new therapeutic option for patients affected by advanced disease. Besides systemic therapy, such as vismodegib and sonidegib, also topical inhibitors have been developed. Patidegib is able to decrease tumor burden, reducing the adverse effects induced by systemic targeted therapies. METHODS: We performed comprehensive research to summarize the use of patidegib in advanced and recurrent aggressive basal cell carcinomas. Only English language human studies were included in the search. RESULTS: Seven trials reported the application of patidegib. Both topical and systemic patidegib demonstrated safety, tolerability, and efficacy in naïve patients with stage II and III basal cell carcinomas, while stage IV disease and not-naïve patients did not show any benefit. CONCLUSION: Unlike systemic Hedgehog pathway inhibitors, patidegib 2% gel is not associated with systemic adverse effects and allows a better patient management. Considering the multidisciplinary management of neoplasia, in the era of precision medicine, it is mandatory to confide in pharmacogenomics to obtain personalized combined or sequential therapies.


Assuntos
Antineoplásicos/uso terapêutico , Dermatologia , Proteínas Hedgehog/metabolismo , Terapia de Alvo Molecular , Transdução de Sinais/efeitos dos fármacos , Antineoplásicos/química , Antineoplásicos/farmacologia , Compostos de Bifenilo , Ensaios Clínicos como Assunto , Dermatologia/métodos , Humanos , Prognóstico , Piridinas , Neoplasias Cutâneas/tratamento farmacológico , Neoplasias Cutâneas/metabolismo , Resultado do Tratamento , Alcaloides de Veratrum
18.
PLoS One ; 16(9): e0257395, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34534256

RESUMO

Sensory experience modulates proliferation, differentiation, and migration of oligodendrocyte progenitor cells (OPCs). In the mouse primary visual cortex (V1), visual deprivation-dependent modulation of OPCs has not been demonstrated. Here, we demonstrate that undifferentiated OPCs developmentally peaked around postnatal day (P) 25, and binocular enucleation (BE) from the time of eye opening (P14-15) elevated symmetrically-divided undifferentiated OPCs in a reversible G0/G1 state even more at the bottom lamina of the cortex by reducing maturing oligodendrocyte (OL) lineage cells. Experiments using the sonic hedgehog (Shh) signaling inhibitor cyclopamine in vivo suggested that Shh signaling pathway was involved in the BE-induced undifferentiation process. The undifferentiated OPCs then differentiated within 5 days, independent of the experience, becoming mostly quiescent cells in control mice, while altering the mode of sister cell symmetry and forming quiescent as well as maturing cells in the enucleated mice. At P50, BE increased mature OLs via symmetric and asymmetric modes of cell segregation, resulting in more populated mature OLs at the bottom layer of the cortex. These data suggest that fourth postnatal week, corresponding to the early critical period of ocular dominance plasticity, is a developmentally sensitive period for OPC state changes. Overall, the visual loss promoted undifferentiation at the early period, but later increased the formation of mature OLs via a change in the mode of cell type symmetry at the bottom layer of mouse V1.


Assuntos
Proteínas Hedgehog/genética , Oligodendroglia/citologia , Células-Tronco/citologia , Córtex Visual/fisiologia , Animais , Diferenciação Celular , Divisão Celular , Linhagem da Célula , Proliferação de Células , Olho , Camundongos , Camundongos Endogâmicos C57BL , Modelos Estatísticos , Neurogênese , Células Precursoras de Oligodendrócitos/metabolismo , Transdução de Sinais , Alcaloides de Veratrum/farmacologia , Córtex Visual/metabolismo
19.
Pharm Biol ; 59(1): 974-985, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34348563

RESUMO

CONTEXT: Eriodictyol (EDT) is a flavonoid with strong anti-inflammatory, anti-apoptotic, and antioxidant properties. OBJECTIVE: To investigate the protective effect and mechanism of EDT in ulcerative colitis (UC). MATERIALS AND METHODS: UC model was induced by 3% dextran sulphate sodium (DSS) solution for 7 days, meanwhile, EDT and Smoothened (Smo) inhibitor cyclopamine (Cyc) were intraperitoneally injected. In the first experiment, C57BL/6 mice divided into blank control, DSS, DSS + EDT (20 or 40 mg/kg) groups. In second experiment, added Cyc (5 mg/kg) and EDT + Cyc groups. All mice were sacrificed on day 8. Disease activity index (DAI), colon length and colon histology as well as MDA levels, SOD, and GSH-Px activities were measured. The expression of Sonic hedgehog (Shh), Patched, Smo, glioblastoma-1, zonula occludens-1 (ZO-1), occludin, cleaved caspase 3, Bax and Bcl-2 in colon was detected using RT-PCR and Western blotting. RESULTS: After EDT treatment, compared with the DSS group, DAI (2.33 ± 0.516 vs. 3.67 ± 0.516), colon shortening (5.27 ± 0.476 vs. 4.53 ± 0.528 cm) and histological score (6.67 ± 1.211 vs. 12 ± 1.265) was significantly decreased. EDT also reduced inflammation, oxidative stress and apoptosis in colon. Additionally, EDT increased the expression of the tight junction proteins ZO-1 (35%) and occludin (66.3%). Mechanistically, EDT upregulated the Shh signalling pathway. However, Cyc-mediated inhibition of the Shh pathway partially abolished the effects of EDT. DISCUSSION AND CONCLUSIONS: These results indicate EDT attenuates DSS-induced colitis by activating the Shh pathway. Further clinical trials are needed to demonstrate its efficacy on UC.


Assuntos
Colite Ulcerativa/tratamento farmacológico , Colo/patologia , Flavanonas/farmacologia , Proteínas Hedgehog/metabolismo , Animais , Colite Ulcerativa/induzido quimicamente , Colo/efeitos dos fármacos , Citocinas/efeitos dos fármacos , Sulfato de Dextrana/farmacologia , Inflamação/tratamento farmacológico , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Modelos Animais , Estresse Oxidativo/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Alcaloides de Veratrum/farmacologia
20.
Proc Natl Acad Sci U S A ; 118(34)2021 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-34417306

RESUMO

In this study, we use molecular genetic approaches to clarify the role of the Hedgehog (Hh) pathway in regulating the blood-brain/spinal cord barrier (BBB) in the adult mouse central nervous system (CNS). Our work confirms and extends prior studies to demonstrate that astrocytes are the predominant cell type in the adult CNS that transduce Hh signaling, revealed by the expression of Gli1, a target gene of the canonical pathway that is activated in cells receiving Hh, and other key pathway transduction components. Gli1+ (Hh-responsive) astrocytes are distributed in specific regions of the CNS parenchyma, including layers 4/5/6 of the neocortex, hypothalamus, thalamus, and spinal cord, among others. Notably, although BBB properties in endothelial cells are normally regulated by both paracellular and transcellular mechanisms, conditional inactivation of Hh signaling in astrocytes results in transient, region-specific BBB defects that affect transcytosis but not paracellular diffusion. These findings stand in contrast to prior studies that implicated astrocytes as a source of Sonic hedgehog that limited extravasation via both mechanisms [J. I. Alvarez et al., Science 334, 1727-1731 (2011)]. Furthermore, using three distinct Cre driver lines as well as pharmacological approaches to inactivate Hh-pathway transduction globally in CNS astrocytes, we find that these specific BBB defects are only detected in the rostral hypothalamus and spinal cord but not the cortex or other regions where Gli1+ astrocytes are found. Together, our data show that Gli1+ Hh-responsive astrocytes have regionally distinct molecular and functional properties and that the pathway is required to maintain BBB properties in specific regions of the adult mammalian CNS.


Assuntos
Astrócitos/metabolismo , Barreira Hematoencefálica/metabolismo , Proteínas Hedgehog/metabolismo , Tamoxifeno/farmacologia , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Gliose/metabolismo , Proteínas Hedgehog/genética , Camundongos , Camundongos Transgênicos , Moduladores Seletivos de Receptor Estrogênico/farmacologia , Receptor Smoothened/genética , Receptor Smoothened/metabolismo , Medula Espinal/efeitos dos fármacos , Alcaloides de Veratrum/farmacologia
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