RESUMO
The chemical classes of semicarbazones, thiosemicarbazones, and hydrazones are present in various compounds, each demonstrating diverse biological activities. Extensive studies have revealed their potential as schistosomicidal agents. Thiosemicarbazones, in particular, have shown inhibitory effects on Schistosoma mansoni's cathepsin B1 enzyme (SmCB1), which plays a crucial role in hemoglobin degradation within the worm's gut and its nutrition processes. Consequently, SmCB1 has emerged as a promising target for novel schistosomiasis therapies. Moreover, chloroquinoline exhibits characteristics in its aromatic structure that hold promise for developing SmCB1 inhibitors, along with its interaction with hemoglobin's heme group, potentially synergizing against the parasite's gut. In this context, we report the synthesis of 22 hybrid analogs combining hydrazones and quinolines, evaluated against S. mansoni. Five of these hybrids demonstrated schistosomicidal activity in vitro, with GPQF-8Q10 being the most effective, causing worm mortality within 24 h at a concentration of 25 µM. GPQF-8Q8 proved to be the most promising in vivo, significantly reducing egg presence in feces (by 52.8%) and immature eggs in intestines (by 45.8%). These compounds exhibited low cytotoxicity in Vero cells and an in in vivo animal model (Caenorhabditis elegans), indicating a favorable selectivity index. This suggests their potential for the development of new schistosomiasis therapies. Further studies are needed to uncover specific target mechanisms, but these findings offer a promising starting point.
Assuntos
Esquistossomose mansoni , Esquistossomose , Esquistossomicidas , Tiossemicarbazonas , Animais , Chlorocebus aethiops , Schistosoma mansoni , Células Vero , Esquistossomicidas/farmacologia , Tiossemicarbazonas/farmacologia , Hidrazonas/farmacologia , Hemoglobinas/farmacologia , Esquistossomose mansoni/tratamento farmacológicoRESUMO
Inflammatory arthritis, such as rheumatoid arthritis (RA), stands out as one of the main sources of pain and impairment to the quality of life. The use of hemopressin (PVNFKFLSH; Hp), an inverse agonist of type 1 cannabinoid receptor, has proven to be effective in producing analgesia in pain models, but its effect on neuro-inflammatory aspects of RA is limited. In this study, antigen-induced arthritis (AIA) was evoked by the intraarticular (i.art.) injection of methylated bovine serum albumin (mBSA) in male Sprague Dawley rats. Phosphate buffered saline (PBS)-injected ipsilateral knee joints or AIA contralateral were used as control. Nociceptive and inflammatory parameters such as knee joint oedema and leukocyte influx and histopathological changes were carried out in addition to the local measurement of interleukins (IL) IL-6, IL-1ß, tumor necrosis factor-α and the immunoreactivity of the neuropeptides substance P (SP) and calcitonin gene related peptide (CGRP) in the spinal cord (lumbar L3-5 segments) of AIA rats. For 4 days, AIA rats were treated daily with a single administration of saline, Hp injected (10 or 20 µg/day, i.art.), Hp given orally (20 µg/Kg, p.o.) or indomethacin (Indo; 5 mg/Kg, i.p.). In comparison to the PBS control group, the induction of AIA produced a significant and progressive mono-arthritis condition. The degree of AIA severity progressively compromised the normal walking pattern and impaired mobility over the next four days in relation to PBS-injected rats or contralateral knee joints. In AIA rats, the reduction of the distance between footprints and disturbances of gait evidenced signs of nociception. This response worsened at day 4, and a loss of footprint from the ipsilateral hind paw was evident. Daily treatment of the animals with Hp either i.art. (10 and 20 µg/knee) or p.o. (20 µg/Kg) as well as Indo (5 mg/Kg, i.p.) ameliorated the impaired mobility in a time-dependent manner (P < 0.05). In parallel, the AIA-injected ipsilateral knee joints reach a peak of swelling 24 h after AIA induction, which persisted over the next four days in relation to PBS-injected rats or contralateral knee joints. There was a significant but not dose-dependent inhibitory effect produced by all dosages and routes of Hp treatments on AIA-induced knee joint swelling (P < 0.05). In addition, the increased synovial levels of MPO activity, total leukocytes number and IL-6, but not IL-1ß, were significantly reduced by the lower i.art. dose of Hp. In conclusion, these results successfully demonstrate that Hp may represent a novel therapeutic strategy to treat RA, an effect which is unrelated to the proinflammatory actions of the neuropeptides CGRP and SP.
Assuntos
Anti-Inflamatórios/farmacologia , Artrite Experimental/tratamento farmacológico , Artrite Reumatoide/tratamento farmacológico , Hemoglobinas/farmacologia , Dor Nociceptiva/prevenção & controle , Fragmentos de Peptídeos/farmacologia , Administração Oral , Animais , Anti-Inflamatórios/administração & dosagem , Comportamento Animal/efeitos dos fármacos , Citocinas/metabolismo , Edema/tratamento farmacológico , Marcha/efeitos dos fármacos , Hemoglobinas/administração & dosagem , Inflamação/tratamento farmacológico , Injeções Intra-Articulares , Articulação do Joelho/efeitos dos fármacos , Articulação do Joelho/metabolismo , Articulação do Joelho/patologia , Leucócitos/efeitos dos fármacos , Masculino , Fragmentos de Peptídeos/administração & dosagem , Ratos Sprague-Dawley , Receptores de Peptídeo Relacionado com o Gene de Calcitonina/metabolismo , Substância P/metabolismoRESUMO
Previous studies suggested the pharmacological potential of rat hemopressin (PVNFKFLSH) and its shorter synthetic peptide NFKF, to protect from pilocarpine-induced seizures in mice. Orally administered NFKF was shown to be hundred times more potent than cannabidiol in delaying the first seizure induced by pilocarpine in mice. Here, using an experimental autoimmune encephalomyelitis (EAE) model of multiple sclerosis we have shown that C57BL/6 J mice orally administrated with NFKF (500 µg/kg) presented better EAE clinical scores and improved locomotor activity compared to saline administrated control mice. NFKF blocked the production of IL-1beta and IL-6, and has high scores binding cannabinoid type 2 receptors. Therefore, NFKF is an exciting new possibility to neurodegenerative diseases therapeutics.
Assuntos
Encefalomielite Autoimune Experimental/metabolismo , Encefalomielite Autoimune Experimental/prevenção & controle , Hemoglobinas/uso terapêutico , Fármacos Neuroprotetores/uso terapêutico , Fragmentos de Peptídeos/uso terapêutico , Animais , Citocinas/antagonistas & inibidores , Citocinas/metabolismo , Encefalomielite Autoimune Experimental/patologia , Feminino , Hemoglobinas/química , Hemoglobinas/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Simulação de Acoplamento Molecular/métodos , Fármacos Neuroprotetores/química , Fármacos Neuroprotetores/farmacologia , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/farmacologia , RatosRESUMO
LVV-hemorphin-6 (LVV-h6) is bioactive peptide and is a product of the degradation of hemoglobin. Since LVV-h6 effects are possibly mediated by opioid or AT4/IRAP receptors, we hypothesized that LVV-h6 would modify behavior. We evaluated whether LVV-h6 affects: i) anxiety-like behavior and locomotion; ii) depression-like behavior; iii) cardiovascular and neuroendocrine reactivity to emotional stress. Male Wistar rats ( ± 300 g) received LVV-h6 (153 nmol/kg i.p.) or vehicle (NaCl 0.9% i.p.). We used: i) open field (OF) test for locomotion; ii) elevated plus maze (EPM) for anxiety-like behavior; iii) forced swimming test (FST) for depression-like behavior and iv) air jet for cardiovascular and neuroendocrine reactivity to stress. Diazepam (2 mg/kg i.p.) and imipramine (15 mg/kg i.p.) were used as positive control for EPM and FST, respectively. To evaluate the LVV-h6 mechanisms, we used: the antagonist of oxytocin (OT) receptors (atosiban - ATS 1 and 0.1 mg/kg i.p.); the inhibitor of tyrosine hydroxylase (Alpha-methyl-p-tyrosine - AMPT 200 mg/kg i.p.) to investigate the involvement of catecholaminergic paths; and the antagonist of opioid receptors (naltrexone - NTX 0.3 mg/kg s.c.). We found that LVV-h6: i) evoked anxiolytic-like effect; ii) evoked antidepressant-like effect in the FST; and iii) did not change the locomotion, neuroendocrine and cardiovascular responses to stress. The LVV-h6 anxiolytic-like effect was not reverted by ATS and AMPT. However, the antidepressant effects were reverted only by NTX. Hence, our findings demonstrate that LVV-h6 modulates anxiety-like behavior by routes that are not oxytocinergic, catecholaminergic or opioid. The antidepressant-like effects of LVV-h6 rely on opioid pathways.
Assuntos
Ansiolíticos/farmacologia , Antidepressivos/farmacologia , Ansiedade , Comportamento Animal/classificação , Depressão , Hemoglobinas/farmacologia , Fragmentos de Peptídeos/farmacologia , Animais , Ansiedade/tratamento farmacológico , Ansiedade/metabolismo , Ansiedade/fisiopatologia , Depressão/tratamento farmacológico , Depressão/metabolismo , Depressão/fisiopatologia , Masculino , Ratos , Ratos WistarRESUMO
LVV-hemorphin-7 (LVV-h7) is bioactive peptide resulting from degradation of hemoglobin ß-globin chain. LVV-h7 is a specific agonist of angiotensin IV receptor. This receptor belongs to the class of insulin-regulated aminopeptidases (IRAP), which displays oxytocinase activity. Herein, our aims were to assess whether: i) LVV-h7 modifies centrally organized behavior and cardiovascular responses to stress and ii) mechanisms underlying LVV-h7 effects involve activation of oxytocin (OT) receptors, probably as result of reduction of IRAP proteolytic activity upon OT. Adult male Wistar rats (270-370g) received (i.p.) injections of LVV-h7 (153nmol/kg), or vehicle (0.1ml). Different protocols were used: i) open field (OP) test for locomotor/exploratory activities; ii) Elevated Plus Maze (EPM) for anxiety-like behavior; iii) forced swimming test (FST) test for depression-like behavior and iv) air jet for cardiovascular reactivity to acute stress exposure. Diazepam (2mg/kg) and imipramine (15mg/kg) were used as positive control for EPM and FST, respectively. The antagonist of OT receptors (OTr), atosiban (1 and 0,1mg/kg), was used to determine the involvement of oxytocinergic paths. We found that LVV-h7: i) increased the number of entries and the time spent in open arms of the maze, an indicative of anxiolysis; ii) provoked antidepressant effect in the FS test; and iii) increased the exploration and locomotion; iv) did not change the cardiovascular reactivity and neuroendocrine responses to acute stress. Also, increases in locomotion and the antidepressant effects evoked by LVV-h7 were reverted by OTr antagonist. We conclude that LVV-h7 modulates behavior, displays antidepressant and anxiolytic effects that are mediated in part by oxytocin receptors.
Assuntos
Ansiolíticos/farmacologia , Antidepressivos/farmacologia , Comportamento Animal/efeitos dos fármacos , Hemoglobinas/farmacologia , Atividade Motora/efeitos dos fármacos , Fragmentos de Peptídeos/farmacologia , Receptores de Ocitocina/metabolismo , Animais , Ansiolíticos/uso terapêutico , Antidepressivos/uso terapêutico , Ansiedade/tratamento farmacológico , Ansiedade/metabolismo , Depressão/tratamento farmacológico , Depressão/metabolismo , Diazepam/farmacologia , Hemoglobinas/uso terapêutico , Antagonistas de Hormônios/farmacologia , Imipramina/farmacologia , Masculino , Fragmentos de Peptídeos/uso terapêutico , Ratos , Ratos Wistar , Receptores de Ocitocina/antagonistas & inibidores , Vasotocina/análogos & derivados , Vasotocina/farmacologiaRESUMO
There is a 0.138% incidence of adverse reactions related to blood transfusion. Transfusion-related acute lung injury, immunosuppression, fever, pathogen transmission, and hemolytic transfusion reactions are the most common ones. Synthetic oxygen carriers have been developed to deal with blood shortages and for use in the field where stored blood was not available. They were also designed to be pathogen free, including unknown viruses. In this study, we used Male Golden Syrian Hamsters implemented with a dorsal window chamber to determine how infusion of three different, genetically crosslinked recombinant acellular hemoglobin (rHb) solutions with different oxygen affinities and nitric oxide kinetics affect mean arterial pressure (MAP), heart rate (HR), kidney function, and kidney structure. We found that the administration of all three rHb solutions caused mild hypertension and bradycardia 30 minutes after infusion. However, acute changes in glomerular filtration rate (GFR) were not detected, even though histological analysis was performed 72 hours after treatment revealed some structural changes. All the rHb solutions resulted in hypertension 30 minutes after a 10% topload administration. Regardless of their properties, the presence of acellular Hb causes significant alterations to kidney tissue.
Assuntos
Substitutos Sanguíneos/farmacologia , Taxa de Filtração Glomerular/efeitos dos fármacos , Hemoglobinas/farmacologia , Rim/fisiopatologia , Animais , Substitutos Sanguíneos/efeitos adversos , Bradicardia/induzido quimicamente , Bradicardia/metabolismo , Bradicardia/fisiopatologia , Cricetinae , Hemoglobinas/efeitos adversos , Hipertensão/induzido quimicamente , Hipertensão/metabolismo , Hipertensão/fisiopatologia , Rim/metabolismo , Masculino , Mesocricetus , Proteínas Recombinantes/efeitos adversos , Proteínas Recombinantes/farmacologiaRESUMO
BACKGROUND AND PURPOSE: The function of the endocannabinoid system (ECS) in renal tissue is not completely understood. Kidney function is closely related to ion reabsorption in the proximal tubule, the nephron segment responsible for the re-absorption of 70-80% of the filtrate. We studied the effect of compounds modulating the activity of cannabinoid (CB) receptors on the active re-absorption of Na(+) in LLC-PK1 cells. EXPERIMENTAL APPROACH: Changes in Na(+) /K(+) -ATPase activity were assessed after treatment with WIN55,212-2 (WIN), a non-selective lipid agonist, and haemopressin (HP), an inverse peptide agonist at CB1 receptors. Pharmacological tools were used to investigate the signalling pathways involved in the modulation of Na(+) transport. KEY RESULTS: In addition to CB1 and CB2 receptors and TRPV1 channels, the mRNAs encoding for enzymes of the ECS were also expressed in LLC-PK1. WIN (10(-7) M) and HP (10(-6) M) altered Na(+) re-absorption in LLC-PK1 in a dual manner. They both acutely (after 1 min) increased Na(+) /K(+) -ATPase activity in a TRPV1 antagonist-sensitive way. WIN's stimulating effect persisted for 30 min, and this effect was partially blocked by a CB1 antagonist or a PKC inhibitor. In contrast, HP inhibited Na(+) /K(+) -ATPase after 30 min incubation, and this effect was attenuated by a CB1 antagonist or a PKA inhibitor. CONCLUSION AND IMPLICATIONS: The ECS is expressed in LLC-PK1 cells. Both CB1 receptors and TRPV1 channels regulate Na(+) /K(+) -ATPase activity in these cells, and are modulated by lipid and peptide CB1 receptor ligands, which act via different signalling pathways.
Assuntos
Endocanabinoides/metabolismo , Rim/metabolismo , Receptor CB1 de Canabinoide/metabolismo , Sódio/metabolismo , Animais , Benzoxazinas/farmacologia , Transporte Biológico , AMP Cíclico/metabolismo , Hemoglobinas/farmacologia , Células LLC-PK1 , Morfolinas/farmacologia , Naftalenos/farmacologia , Fragmentos de Peptídeos/farmacologia , Piperidinas/farmacologia , Pirazóis/farmacologia , Receptor CB1 de Canabinoide/agonistas , Receptor CB1 de Canabinoide/antagonistas & inibidores , Receptor CB2 de Canabinoide/metabolismo , Transdução de Sinais , ATPase Trocadora de Sódio-Potássio/metabolismo , Suínos , Canais de Cátion TRPV/metabolismoRESUMO
The antimicrobial activity of hemoglobin fragments (hemocidins) has been reported in a variety of models. The cattle tick Rhipicephalus (Boophilus) microplus is a blood sucking arthropod from where the first in vivo-generated hemocidin was characterized (Hb 33-61). In the present work we identified a novel antimicrobial peptide from the midgut of fully engorged R. (B.) microplus females, which comprises the amino acids 98-114 of the alpha subunit of bovine hemoglobin, and was designated Hb 98-114. This peptide was active against several yeast and filamentous fungi, although no activity was detected against bacteria up to 50µM of the synthetic peptide. Hb 98-114 was capable of permeabilizing Candida albicans cell membrane and had a fungicidal effect against this yeast. Circular dichroism (CD) and nuclear magnetic resonance (NMR) experiments showed that Hb 98-114 has a random conformation in aqueous solution but switches to an alpha-helical conformation in the presence of sodium dodecyl sulfate (SDS). This alpha helix adopts an amphipathic structure which may be the mechanism of cell membrane permeabilization. Importantly, Hb 98-114 may play an important role in defending the tick midgut against fungal pathogens and is the first hemocidin with specific antifungal activity to be characterized.
Assuntos
Antibacterianos/farmacologia , Antifúngicos/farmacologia , Trato Gastrointestinal/química , Hemoglobinas/farmacologia , Fragmentos de Peptídeos/farmacologia , Rhipicephalus , Sequência de Aminoácidos , Animais , Antibacterianos/química , Antibacterianos/isolamento & purificação , Antifúngicos/química , Antifúngicos/isolamento & purificação , Bovinos , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Cromatografia Líquida de Alta Pressão , Cromatografia de Fase Reversa , Enterobacteriaceae/efeitos dos fármacos , Feminino , Corantes Fluorescentes/metabolismo , Bacilos Gram-Positivos Formadores de Endosporo/efeitos dos fármacos , Hemoglobinas/química , Hemoglobinas/isolamento & purificação , Testes de Sensibilidade Microbiana , Fungos Mitospóricos/efeitos dos fármacos , Fungos Mitospóricos/metabolismo , Modelos Moleculares , Dados de Sequência Molecular , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/isolamento & purificação , Permeabilidade , Estrutura Secundária de Proteína , Pseudomonas aeruginosa/efeitos dos fármacosRESUMO
Mammalian spermatozoa are not able to fertilize an egg immediately upon ejaculation. They acquire this ability during their transit through the female genital tract in a process known as capacitation. The mammalian oviduct acts as a functional sperm reservoir providing a suitable environment that allows the maintenance of sperm fertilization competence until ovulation occurs. After ovulation, spermatozoa are gradually released from the oviductal reservoir in the caudal isthmus and ascend to the site of fertilization. Capacitating-related changes in sperm plasma membrane seem to be responsible for sperm release from oviductal epithelium. Anandamide is a lipid mediator that participates in the regulation of several female and male reproductive functions. Previously we have demonstrated that anandamide was capable to release spermatozoa from oviductal epithelia by induction of sperm capacitation in bovines. In the present work we studied whether anandamide might exert its effect by activating the nitric oxide (NO) pathway since this molecule has been described as a capacitating agent in spermatozoa from different species. First, we demonstrated that 1 µM NOC-18, a NO donor, and 10 mM L-Arginine, NO synthase substrate, induced the release of spermatozoa from the oviductal epithelia. Then, we observed that the anandamide effect on sperm oviduct interaction was reversed by the addition of 1 µM L-NAME, a NO synthase inhibitor, or 30 µg/ml Hemoglobin, a NO scavenger. We also demonstrated that the induction of bull sperm capacitation by nanomolar concentrations of R(+)-methanandamide or anandamide was inhibited by adding L-NAME or Hemoglobin. To study whether anandamide is able to produce NO, we measured this compound in both sperm and oviductal cells. We observed that anandamide increased the levels of NO in spermatozoa, but not in oviductal cells. These findings suggest that anandamide regulates the sperm release from oviductal epithelia probably by activating the NO pathway during sperm capacitation.
Assuntos
Ácidos Araquidônicos/farmacologia , Tubas Uterinas/citologia , Tubas Uterinas/metabolismo , Óxido Nítrico/metabolismo , Alcamidas Poli-Insaturadas/farmacologia , Transdução de Sinais/efeitos dos fármacos , Espermatozoides/citologia , Animais , Bovinos , Comunicação Celular/efeitos dos fármacos , Endocanabinoides , Células Epiteliais/citologia , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Tubas Uterinas/efeitos dos fármacos , Feminino , Hemoglobinas/farmacologia , Masculino , NG-Nitroarginina Metil Éster/farmacologia , Doadores de Óxido Nítrico/farmacologia , Óxido Nítrico Sintase Tipo I/metabolismo , Óxido Nítrico Sintase Tipo III/metabolismo , Receptor CB1 de Canabinoide/metabolismo , Espermatozoides/efeitos dos fármacos , Espermatozoides/enzimologia , Canais de Cátion TRPV/metabolismoRESUMO
Phytomonas serpens synthesizes metallo- and cysteine-proteases that are related to gp63 and cruzipain, respectively, two virulence factors produced by pathogenic trypanosomatids. Here, we described the cellular distribution of gp63- and cruzipain-like molecules in P. serpens through immunocytochemistry and confocal fluorescence microscopy. Both proteases were detected in distinct cellular compartments, presenting co-localization in membrane domains and intracellular regions. Subsequently, we showed that exogenous proteins modulated the production of both protease classes, but in different ways. Regarding the metalloprotease, only fetal bovine serum (FBS) influenced the gp63 expression, reducing its surface exposition (≈30%). Conversely, the cruzipain-like molecule was differentially modulated according to the proteins: human and bovine albumins reduced its expression around 50% and 35%, respectively; mucin and FBS did not alter its production, while IgG and hemoglobin drastically enhanced its surface exposition around 7- and 11-fold, respectively. Additionally, hemoglobin induced an augmentation in the cell-associated cruzipain-like activity in a dose-dependent manner. A twofold increase of the secreted cruzipain-like protein was detected after parasite incubation with 1% hemoglobin compared to the parasites incubated in PBS-glucose. The results showed the ability of P. serpens in modulating the expression and the activity of proteolytic enzymes after exposition to exogenous proteins, with emphasis in its cruzipain-like molecules.