Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 34
Filtrar
Mais filtros










Intervalo de ano de publicação
1.
Artigo em Inglês | MEDLINE | ID: mdl-38362565

RESUMO

Background: The bioactive peptides derived from snake venoms of the Viperidae family species have been promising as therapeutic candidates for neuroprotection due to their ability to prevent neuronal cell loss, injury, and death. Therefore, this study aimed to evaluate the cytoprotective effects of a synthetic proline-rich oligopeptide 7a (PRO-7a;

2.
J. venom. anim. toxins incl. trop. dis ; 30: e20230043, 2024. graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1534803

RESUMO

Background: The bioactive peptides derived from snake venoms of the Viperidae family species have been promising as therapeutic candidates for neuroprotection due to their ability to prevent neuronal cell loss, injury, and death. Therefore, this study aimed to evaluate the cytoprotective effects of a synthetic proline-rich oligopeptide 7a (PRO-7a; <EDGPIPP) from Bothrops jararaca snake, on oxidative stress-induced toxicity in neuronal PC12 cells and astrocyte-like C6 cells. Methods: Both cells were pre-treated for four hours with different concentrations of PRO-7a, submitted to H2O2-induced damage for 20 h, and then the oxidative stress markers were analyzed. Also, two independent neuroprotective mechanisms were investigated: a) L-arginine metabolite generation via argininosuccinate synthetase (AsS) activity regulation to produce agmatine or polyamines with neuroprotective properties; b) M1 mAChR receptor subtype activation pathway to reduce oxidative stress and neuron injury. Results: PRO-7a was not cytoprotective in C6 cells, but potentiated the H2O2-induced damage to cell integrity at a concentration lower than 0.38 μM. However, PRO-7a at 1.56 µM, on the other hand, modified H2O2-induced toxicity in PC12 cells by restoring cell integrity, mitochondrial metabolism, ROS generation, and arginase indirect activity. The α-Methyl-DL-aspartic acid (MDLA) and L-NΩ-Nitroarginine methyl ester (L-Name), specific inhibitors of AsS and nitric oxide synthase (NOS), which catalyzes the synthesis of polyamines and NO from L-arginine, did not suppress PRO-7a-mediated cytoprotection against oxidative stress. It suggested that its mechanism is independent of the production of L-arginine metabolites with neuroprotective properties by increased AsS activity. On the other hand, the neuroprotective effect of PRO-7a was blocked in the presence of dicyclomine hydrochloride (DCH), an M1 mAChR antagonist. Conclusions: For the first time, this work provides evidence that PRO-7a-induced neuroprotection seems to be mediated through M1 mAChR activation in PC12 cells, which reduces oxidative stress independently of AsS activity and L-arginine bioavailability.(AU)


Assuntos
Oligopeptídeos/efeitos adversos , Receptores Muscarínicos/química , Venenos de Crotalídeos/síntese química , Prolina , Estresse Oxidativo
3.
Toxicon ; 231: 107178, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37302421

RESUMO

Venom-derived proteins and peptides have prevented neuronal cell loss, damage, and death in the study of neurodegenerative disorders. The cytoprotective effects of the peptide fraction (PF) from Bothrops jararaca snake venom were evaluated against oxidative stress changes in neuronal PC12 cells and astrocyte-like C6 cells. PC12 and C6 cells were pre-treated for 4 h with different concentrations of PF, and then H2O2 was added (0.5 mM in PC12 cells; 0.4 mM in C6 cells) and incubated for 20 h more. In PC12 cells, PF at 0.78 µg mL-1 increased viability (113.6 ± 6.3%) and metabolism (96.3 ± 10.3%) cell against H2O2-induced neurotoxicity (75.6 ± 5.8%; 66.5 ± 3.3%, respectively), reducing oxidative stress markers such as ROS generation, NO production, and arginase indirect activity through urea synthesis. Despite that, PF showed no cytoprotective effects in C6 cells, but potentiated the H2O2-induced damage at a concentration lower than 0.07 µg mL-1. Furthermore, the role of metabolites derived from L-arginine metabolism was verified in PF-mediated neuroprotection in PC12 cells, using specific inhibitors of two of the key enzymes in the L-arginine metabolic pathway: the α-Methyl-DL-aspartic acid (MDLA) to argininosuccinate synthetase (AsS), responsible for the recycling of L-citrulline to L-arginine; and, L-NΩ-Nitroarginine methyl ester (L-Name) to nitric oxide synthase (NOS), which catalyzes the synthesis of NO from L-arginine. The inhibition of AsS and NOS suppressed PF-mediated cytoprotection against oxidative stress, indicating that its mechanism is dependent on the production pathway of L-arginine metabolites such as NO and, more importantly, polyamines from ornithine metabolism, which are involved in the neuroprotection mechanism described in the literature. Overall, this work provides novel opportunities for evaluating whether the neuroprotective properties of PF shown in particular neuronal cells are sustained and for exploring potential drug development pathways for the treatment of neurodegenerative diseases.


Assuntos
Bothrops , Animais , Ratos , Arginina/metabolismo , Arginina/farmacologia , Astrócitos/metabolismo , Bothrops/metabolismo , Peróxido de Hidrogênio , Óxido Nítrico Sintase/metabolismo , Óxido Nítrico Sintase/farmacologia , Estresse Oxidativo , Células PC12 , Peptídeos/farmacologia , Venenos de Serpentes/metabolismo
4.
Cell Mol Neurobiol ; 43(3): 1163-1180, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35674974

RESUMO

Methylmalonic acidemia is an organic acidemia caused by deficient activity of L-methylmalonyl-CoA mutase or its cofactor cyanocobalamin and it is biochemically characterized by an accumulation of methylmalonic acid (MMA) in tissue and body fluids of patients. The main clinical manifestations of this disease are neurological and observable symptoms during metabolic decompensation are encephalopathy, cerebral atrophy, coma, and seizures, which commonly appear in newborns. This study aimed to investigate the toxic effects of MMA in a glial cell line presenting astrocytic features. Astroglial C6 cells were exposed to MMA (0.1-10 mM) for 24 or 48 h and cell metabolic viability, glucose consumption, and oxygen consumption rate, as well as glutamate uptake and ATP content were analyzed. The possible preventive effects of bezafibrate were also evaluated. MMA significantly reduced cell metabolic viability after 48-h period and increased glucose consumption during the same period of incubation. Regarding the energy homeostasis, MMA significantly reduced respiratory parameters of cells after 48-h exposure, indicating that cell metabolism is compromised at resting and reserve capacity state, which might influence the cell capacity to meet energetic demands. Glutamate uptake and ATP content were also compromised after exposure to MMA, which can be influenced energy metabolism impairment, affecting the functionality of the astroglial cells. Our findings suggest that these effects could be involved in the pathophysiology of neurological dysfunction of this disease. Methylmalonic acid compromises mitochondrial functioning leading to reduced ATP production and reduces glutamate uptake by C6 astroglial cells.


Assuntos
Glioma , Ácido Glutâmico , Ratos , Animais , Ácido Glutâmico/metabolismo , Ácido Metilmalônico/toxicidade , Respiração Celular , Trifosfato de Adenosina/metabolismo
5.
Biofouling ; 38(5): 427-440, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35670068

RESUMO

Candida krusei is a candidiasis etiological agent of relevance in the clinical setting because of its intrinsic resistance to fluconazole. Also, it has opened up new paths in the area of alternative therapeutic techniques. This project demonstrated the effects of diphenyl diselenide (PhSe)2 and p-cloro diphenyl diselenide (pCl-PhSe)2, two organochalcogen compounds, on relevant virulence factors for the early stage of the C. krusei host interaction and infection process. Both compounds inhibited adherence of C. krusei to both polystyrene surfaces and cervical epithelial cells and biofilm formation; the structure of the biofilm was also changed in a dose-dependent manner. In addition, both compounds inhibited C. krusei growth, but (PhSe)2 significantly increased the time duration of the lag phase and delayed the start of the exponential phase in growth kinetics. (PhSe)2 has more potential antifungal activity than (pCl-PhSe)2 in inhibiting the adherence to epithelial cells, biofilm formation, and growth of C. krusei.


Assuntos
Biofilmes , Fatores de Virulência , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Derivados de Benzeno , Fluconazol/farmacologia , Compostos Organosselênicos , Pichia
6.
J Trace Elem Med Biol ; 73: 127019, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35709560

RESUMO

BACKGROUND: Systemic candidiasis is produced by Candida albicans or non-albicans Candida species, opportunistic fungi that produce both superficial and invasive infections. Despite the availability of a wide range of antifungal agents for the treatment of candidiasis, failure of therapy is observed frequently, which opens new avenues in the field of alternative therapeutic strategies. METHODS: The effects of p,p'-methoxyl-diphenyl diselenide [(MeOPhSe)2], a synthetic organic selenium (organochalcogen) compound, were investigated on virulence factors of C. krusei and compared with its antifungal effects on the virulence factors related to adhesion to cervical epithelial cell surfaces with C. albicans. RESULTS: (MeOPhSe)2, a compound non-toxic in epithelial (HeLa) and fibroblastic (Vero) cells, inhibited the growth in a dose-dependent manner and changed the kinetics parameters of C. krusei and, most importantly, extending the duration of lag phase of growth, inhibiting biofilm formation, and changing the structure of biofilm. Also, (MeOPhSe)2 reduced C. albicans and C. krusei adherence to cervical epithelial cells, an important factor for the early stage of the Candida-host interaction. The reduction was 37.24 ± 2.7 % in C. krusei (p = 0.00153) and 32.84 ± 3.2 % in C. albicans (p = 0.0072) at 20 µM (MeOPhSe)2, and the effect is in a concentration-dependent manner. Surprisingly, the antifungal potential on adhesion was similar between both species, indicating the potential of (MeOPhSe)2 as a promising antifungal drug against different Candida infections. CONCLUSION: Overall, we demonstrated the potential of (MeOPhSe)2 as an effective antifungal drug against the virulence factors of Candida species.


Assuntos
Antifúngicos , Selênio , Antifúngicos/química , Antifúngicos/farmacologia , Derivados de Benzeno , Biofilmes , Candida , Candida albicans , Células Epiteliais , Testes de Sensibilidade Microbiana , Compostos Organosselênicos , Pichia , Selênio/metabolismo , Selênio/farmacologia , Fatores de Virulência/metabolismo , Fatores de Virulência/farmacologia
7.
J Environ Sci Health B ; 57(7): 554-560, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35583269

RESUMO

Tetraethyl pyrophosphate (TEPP) is an organophosphate pesticide that irreversibly inhibits acetylcholinesterase (AChE). Cork powder or granules have been recommended as a sustainable sorbent to remove pesticides from water. In the present study, we evaluated the effectiveness of removing TEPP from water using wine corks to obtain cork granules as natural adsorbent, analyzing the TEPP effects on AChE activity in commercial enzyme from Electrophorus electricus and secreted by neuronal PC12 cells. TEPP inhibited AChE activity in a concentration-dependent manner. For the first time, we showed that different concentrations of TEPP diluted in water after adsorption experiments using cork granules decreased TEPP's inhibitory effects on AChE activity in commercial enzyme and neuronal PC12 cell culture medium. Our results suggest that the optimum removal of TEPP from water by corks was 91.4 ± 4.0%. Overall, the findings support the hypothesis that cork granules can be used to remediate pesticide-contaminated environments, such as those contaminated by organophosphate pesticides, and demonstrate a new application of a biochemical assay on AChE activity using a commercial enzyme or secreted by neuronal PC12 cells in culture as a possible methodologic strategy for evaluating the success of TEPP removal from water.


Assuntos
Acetilcolinesterase , Praguicidas , Animais , Organofosfatos , Compostos Organofosforados , Células PC12 , Praguicidas/farmacologia , Ratos , Água
8.
Toxicon ; 207: 52-59, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34999120

RESUMO

The crude venom of the Bothrops jararaca snake (Bj-CV) is a complex mixture of biologically active proteins that includes a variety of peptides in the low molecular weight fraction (Bj-PF). We investigated how an intramuscular injection of Bj-CV (1.2 mg kg-1) and Bj-PF (0.24 mg kg-1) influenced lung mechanics and lung and muscle inflammation in male Swiss mice 15 min, 1, 6, and 24 h after inoculation. Pressure dissipation against lung resistive components (ΔP1) rose significantly from 1 to 24 h after Bj-CV and 6-24 h after Bj-PF inoculation. Both Bj-CV and Bj-PF increased the total pressure variation of the lung (ΔPtot) 24 h after injection. Lung static elastance increased significantly after injection in all time periods investigated by Bj-CV and from 6 to 24 h by Bj-PF. Lung static elastance increased significantly after injection in all time periods investigated by Bj-CV and from 6 to 24 h by Bj-PF. Furthermore, intramuscular inoculation of Bj-CV and Bj-PF resulted in an increase in muscle and pulmonary inflammation, as evidenced by an increase in leukocyte influx when compared to the control group. Finally, both Bj-CV and Bj-PF cause acute lung injury, as shown by pulmonary inflammation and decreased lung mechanics. Furthermore, the fact that Bj-PF produces mechanical alterations in the lungs and muscular inflammation implies that non-enzymatic compounds can cause inflammation.


Assuntos
Bothrops , Venenos de Crotalídeos , Animais , Venenos de Crotalídeos/toxicidade , Leucócitos , Pulmão , Masculino , Camundongos , Peptídeos
9.
Toxins (Basel) ; 13(12)2021 12 10.
Artigo em Inglês | MEDLINE | ID: mdl-34941722

RESUMO

Venoms of solitary wasps are utilized for prey capture (insects and spiders), paralyzing them with a stinger injection to be offered as food for their larvae. Thus, the identification and characterization of the components of solitary wasp venoms can have biotechnological application. In the present study, the venom components profile of a solitary scoliid wasp, Campsomeriella annulata annulata, was investigated through a comprehensive analysis using LC-MS and -MS/MS. Online mass fingerprinting revealed that the venom extract contains 138 components, and MS/MS analysis identified 44 complete sequences of the peptide components. The peptides are broadly divided into two classes: bradykinin-related peptides, and linear α-helical peptides. Among the components of the first class, the two main peptides, α-campsomerin (PRLRRLTGLSPLR) and ß-campsomerin (PRLRRLTGLSPLRAP), had their biological activities evaluated. Both peptides had no effects on metallopeptidases [human neprilysin (NEP) and angiotensin-converting enzyme (ACE)] and acetylcholinesterase (AChE), and had no cytotoxic effects. Studies with PC12 neuronal cells showed that only α-campsomerin was able to enhance cell viability, while ß-campsomerin had no effect. It is noteworthy that the only difference between the primary structures from these peptides is the presence of the AP extension at the C-terminus of ß-campsomerin, compared to α-campsomerin. Among the linear α-helical peptides, annulatin (ISEALKSIIVG-NH2) was evaluated for its biological activities. Annulatin showed histamine releasing activity from mast cells and low hemolytic activity, but no antimicrobial activities against all microbes tested were observed. Thus, in addition to providing unprecedented information on the whole components, the three peptides selected for the study suggest that molecules present in solitary scoliid wasp venoms may have interesting biological activities.


Assuntos
Proteínas de Insetos/química , Proteínas de Insetos/toxicidade , Células PC12/efeitos dos fármacos , Fenômenos Toxicológicos/efeitos dos fármacos , Venenos de Vespas/química , Venenos de Vespas/toxicidade , Animais , Japão , Ratos
10.
Mater Sci Eng C Mater Biol Appl ; 128: 112345, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34474895

RESUMO

Sulforaphane (SFN) is an isothiocyanate with anti-arthritic and immuno-regulatory activities, supported by the downregulation of NF-κB pathway, reduction on metalloproteinases expression and prevention of cytokine-induced cartilage degeneration implicated in OA progression. SFN promising pharmacological effects associated to its possible use, by intra-articular route and directly in contact to the site of action, highlight SFN as promising candidate for the development of drug-delivery systems. The association of poloxamers (PL) and hyaluronic acid (HA) supports the development of osteotrophic and chondroprotective pharmaceutical formulations. This study aims to develop PL-HA hybrid hydrogels as delivery systems for SFN intra-articular release and evaluate their biocompatibility and efficacy for osteoarthritis treatment. All formulations showed viscoelastic behavior and cubic phase organization. SFN incorporation and drug loading showed a concentration-dependent behavior following HA addition. Drug release profiles were influenced by both diffusion and relaxation of polymeric chains mechanisms. The PL407-PL338-HA-SFN hydrogel did not evoke pronounced cytotoxic effects on either osteoblast or chondrosarcoma cell lines. In vitro/ex vivo pharmacological evaluation interfered with an elevated activation of NF-κB and COX-2, increased the type II collagen expression, and inhibited proteoglycan depletion. These results highlight the biocompatibility and the pharmacological efficacy of PL-HA hybrid hydrogels as delivery systems for SFN intra-articular release for OA treatment.


Assuntos
Ácido Hialurônico , Osteoartrite , Cartilagem , Humanos , Hidrogéis , Isotiocianatos/farmacologia , Osteoartrite/tratamento farmacológico , Poloxâmero , Sulfóxidos
11.
J Venom Anim Toxins Incl Trop Dis ; 27: e20200171, 2021 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-34194483

RESUMO

BACKGROUND: Solitary wasp venoms may be a rich source of neuroactive substances, since their venoms are used for paralyzing preys. We have been exploring bioactive constituents of solitary wasp venoms and, in this study, the component profile of the venom from a solitary scoliid wasp, Scolia decorata ventralis, was investigated through a comprehensive analysis using LC-MS. Two peptides were synthesized, and their neuroprotective properties were evaluated. METHODS: A reverse-phase HPLC connected to ESI-MS was used for LC-MS analyses. Online mass fingerprinting was performed from TIC, and data-dependent tandem mass spectrometry gave the MS/MS spectra. The sequences of two major peptide components were determined by MALDI-TOF/TOF MS analysis, confirmed by solid phase synthesis. Using the synthetic peptides, biological activities were assessed. Cell integrity tests and neuroprotection analyzes using H2O2 as an oxidative stress inducer were performed for both peptides. RESULTS: Online mass fingerprinting revealed that the venom contains 123 components, and the MS/MS analysis resulted in 33 full sequences of peptide components. The two main peptides, α-scoliidine (DYVTVKGFSPLR) and ß-scoliidine (DYVTVKGFSPLRKA), present homology with the bradykinin C-terminal. Despite this, both peptides did not behave as substrates or inhibitors of ACE, indicating that they do not interact with this metallopeptidase. In further studies, ß-scoliidine, but not α -scoliidine, showed protective effects against oxidative stress-induced neurotoxicity in PC12 cells through integrity and metabolism cell assays. Interestingly, ß-scoliidine has the extension of the KA dipeptide at the C-terminal in comparison with α-scoliidine. CONCLUSION: Comprehensive LC-MS and MS/MS analyses from the Scolia decorata ventralis venom displayed the component profile of this venom. ß-scoliidine showed an effective cytoprotective effect, probably due to the observed increase in the number of cells. This is the first report of solitary wasp venom peptides showing neuroprotective activity.

12.
Biofouling ; 37(2): 235-245, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33715534

RESUMO

Adhesion capacity on biological surfaces and biofilm formation is considered an important step in the infection process by Candida albicans. The ability of (PhSe)2 and (pCl-PhSe)2, two synthetic organic selenium (organochalcogen) compounds, to act on C. albicans virulence factors related to adhesion to human endocervical (HeLa) cell surfaces and their anti-biofilm activities was analyzed. Both organochalcogen compounds inhibited C. albicans adhesion to HeLa cells, dependent on compound concentrations. (PhSe)2 (at 20 µM; p = 0.0012) was significantly more effective than (pCl-PhSe)2 (at 20 µM; p = 0.0183) compared with the control. (PhSe)2 inhibited biofilm formation and decreased biofilm viability in both early and mature biofilms more efficiently than (pCl-PhSe)2. Overall, the organochalcogen compounds, especially (PhSe)2, were demonstrated to be effective antifungal drugs against C. albicans virulence factors related to epithelial cell surface adhesion and the formation and viability of biofilms.


Assuntos
Biofilmes , Candida albicans , Antifúngicos , Células HeLa , Humanos
13.
Toxins, v. 13, n. 12, 885, dez. 2021
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: bud-4067

RESUMO

Venoms of solitary wasps are utilized for prey capture (insects and spiders), paralyzing them with a stinger injection to be offered as food for their larvae. Thus, the identification and characterization of the components of solitary wasp venoms can have biotechnological application. In the present study, the venom components profile of a solitary scoliid wasp, Campsomeriella annulata annulata, was investigated through a comprehensive analysis using LC-MS and -MS/MS. Online mass fingerprinting revealed that the venom extract contains 138 components, and MS/MS analysis identified 44 complete sequences of the peptide components. The peptides are broadly divided into two classes: bradykinin-related peptides, and linear α-helical peptides. Among the components of the first class, the two main peptides, α-campsomerin (PRLRRLTGLSPLR) and β-campsomerin (PRLRRLTGLSPLRAP), had their biological activities evaluated. Both peptides had no effects on metallopeptidases [human neprilysin (NEP) and angiotensin-converting enzyme (ACE)] and acetylcholinesterase (AChE), and had no cytotoxic effects. Studies with PC12 neuronal cells showed that only α-campsomerin was able to enhance cell viability, while β-campsomerin had no effect. It is noteworthy that the only difference between the primary structures from these peptides is the presence of the AP extension at the C-terminus of β-campsomerin, compared to α-campsomerin. Among the linear α-helical peptides, annulatin (ISEALKSIIVG-NH2) was evaluated for its biological activities. Annulatin showed histamine releasing activity from mast cells and low hemolytic activity, but no antimicrobial activities against all microbes tested were observed. Thus, in addition to providing unprecedented information on the whole components, the three peptides selected for the study suggest that molecules present in solitary scoliid wasp venoms may have interesting biological activities.

14.
J Venom Anim Toxins Incl Trop Dis, v. 27, e20200171, jun. 2021
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: bud-3883

RESUMO

Background Solitary wasp venoms may be a rich source of neuroactive substances, since their venoms are used for paralyzing preys. We have been exploring bioactive constituents of solitary wasp venoms and, in this study, the component profile of the venom from a solitary scoliid wasp, Scolia decorata ventralis, was investigated through a comprehensive analysis using LC-MS. Two peptides were synthesized, and their neuroprotective properties were evaluated. Methods A reverse-phase HPLC connected to ESI-MS was used for LC-MS analyses. Online mass fingerprinting was performed from TIC, and data-dependent tandem mass spectrometry gave the MS/MS spectra. The sequences of two major peptide components were determined by MALDI-TOF/TOF MS analysis, confirmed by solid phase synthesis. Using the synthetic peptides, biological activities were assessed. Cell integrity tests and neuroprotection analyzes using H2O2 as an oxidative stress inducer were performed for both peptides. Results Online mass fingerprinting revealed that the venom contains 123 components, and the MS/MS analysis resulted in 33 full sequences of peptide components. The two main peptides, α-scoliidine (DYVTVKGFSPLR) and β-scoliidine (DYVTVKGFSPLRKA), present homology with the bradykinin C-terminal. Despite this, both peptides did not behave as substrates or inhibitors of ACE, indicating that they do not interact with this metallopeptidase. In further studies, β-scoliidine, but not α -scoliidine, showed protective effects against oxidative stress-induced neurotoxicity in PC12 cells through integrity and metabolism cell assays. Interestingly, β-scoliidine has the extension of the KA dipeptide at the C-terminal in comparison with α-scoliidine. Conclusion Comprehensive LC-MS and MS/MS analyses from the Scolia decorata ventralis venom displayed the component profile of this venom. β-scoliidine showed an effective cytoprotective effect, probably due to the observed increase in the number of cells. This is the first report of solitary wasp venom peptides showing neuroprotective activity.

15.
J. venom. anim. toxins incl. trop. dis ; 27: e20200171, 2021. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1279405

RESUMO

Background Solitary wasp venoms may be a rich source of neuroactive substances, since their venoms are used for paralyzing preys. We have been exploring bioactive constituents of solitary wasp venoms and, in this study, the component profile of the venom from a solitary scoliid wasp, Scolia decorata ventralis, was investigated through a comprehensive analysis using LC-MS. Two peptides were synthesized, and their neuroprotective properties were evaluated. Methods A reverse-phase HPLC connected to ESI-MS was used for LC-MS analyses. Online mass fingerprinting was performed from TIC, and data-dependent tandem mass spectrometry gave the MS/MS spectra. The sequences of two major peptide components were determined by MALDI-TOF/TOF MS analysis, confirmed by solid phase synthesis. Using the synthetic peptides, biological activities were assessed. Cell integrity tests and neuroprotection analyzes using H2O2 as an oxidative stress inducer were performed for both peptides. Results Online mass fingerprinting revealed that the venom contains 123 components, and the MS/MS analysis resulted in 33 full sequences of peptide components. The two main peptides, α-scoliidine (DYVTVKGFSPLR) and β-scoliidine (DYVTVKGFSPLRKA), present homology with the bradykinin C-terminal. Despite this, both peptides did not behave as substrates or inhibitors of ACE, indicating that they do not interact with this metallopeptidase. In further studies, β-scoliidine, but not α -scoliidine, showed protective effects against oxidative stress-induced neurotoxicity in PC12 cells through integrity and metabolism cell assays. Interestingly, β-scoliidine has the extension of the KA dipeptide at the C-terminal in comparison with α-scoliidine. Conclusion Comprehensive LC-MS and MS/MS analyses from the Scolia decorata ventralis venom displayed the component profile of this venom. β-scoliidine showed an effective cytoprotective effect, probably due to the observed increase in the number of cells. This is the first report of solitary wasp venom peptides showing neuroprotective activity.(AU)


Assuntos
Animais , Peptídeos/classificação , Venenos de Vespas , Vespas/metabolismo , Neuroproteção , Estresse Oxidativo , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
16.
J Venom Anim Toxins Incl Trop Dis ; 26: e20200007, 2020 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-32636877

RESUMO

BACKGROUND: Pathogenesis of Bothrops envenomations is complex and despite numerous studies on the effects of this snake venom on various biological systems, relatively little is known about such effects on the male reproductive system. In the present study, the toxicological outcomes of the low molecular weight fraction (LMWF) of B. jararaca snake venom - containing a range of bioactive peptides - were investigated on the dynamics and structure of the seminiferous epithelium and 15P-1 Sertoli cells viability. METHODS: LMWF (5 µg/dose per testis) venom was administered in male Swiss mice by intratesticular (i.t.) injection. Seven days after this procedure, the testes were collected for morphological and morphometric evaluation, distribution of claudin-1 in the seminiferous epithelium by immunohistochemical analyses of testes, and the nitric oxide (NO) levels were evaluated in the total extract of the testis protein. In addition, the toxicological effects of LMWF and crude venom (CV) were analyzed on the 15P-1 Sertoli cell culture. RESULTS: LMWF induced changes in the structure and function of the seminiferous epithelium without altering claudin-1 distribution. LMWF effects were characterized especially by lost cells in the adluminal compartment of epithelium (spermatocytes in pachytene, preleptotene spermatocytes, zygotene spermatocytes, and round spermatid) and different stages of the seminiferous epithelium cycle. LMWF also increased the NO levels in the total extract of the testis protein and was not cytotoxic in concentrations and time tested in the present study. However, CV showed cytotoxicity at 10 µg/mL from 6 to 48 h of treatment. CONCLUSIONS: The major finding of the present study was that the LMWF inhibited spermatozoa production; principally in the spermiogenesis stage without altering claudin-1 distribution in the basal compartment. Moreover, NO increased by LMWF induce open of complexes junctions and release the germ cells of the adluminal compartment to the seminiferous tubule.

17.
J. venom. anim. toxins incl. trop. dis ; 26: e20200007, 2020. graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1135143

RESUMO

Pathogenesis of Bothrops envenomations is complex and despite numerous studies on the effects of this snake venom on various biological systems, relatively little is known about such effects on the male reproductive system. In the present study, the toxicological outcomes of the low molecular weight fraction (LMWF) of B. jararaca snake venom - containing a range of bioactive peptides - were investigated on the dynamics and structure of the seminiferous epithelium and 15P-1 Sertoli cells viability. Methods: LMWF (5 µg/dose per testis) venom was administered in male Swiss mice by intratesticular (i.t.) injection. Seven days after this procedure, the testes were collected for morphological and morphometric evaluation, distribution of claudin-1 in the seminiferous epithelium by immunohistochemical analyses of testes, and the nitric oxide (NO) levels were evaluated in the total extract of the testis protein. In addition, the toxicological effects of LMWF and crude venom (CV) were analyzed on the 15P-1 Sertoli cell culture. Results: LMWF induced changes in the structure and function of the seminiferous epithelium without altering claudin-1 distribution. LMWF effects were characterized especially by lost cells in the adluminal compartment of epithelium (spermatocytes in pachytene, preleptotene spermatocytes, zygotene spermatocytes, and round spermatid) and different stages of the seminiferous epithelium cycle. LMWF also increased the NO levels in the total extract of the testis protein and was not cytotoxic in concentrations and time tested in the present study. However, CV showed cytotoxicity at 10 μg/mL from 6 to 48 h of treatment. Conclusions: The major finding of the present study was that the LMWF inhibited spermatozoa production; principally in the spermiogenesis stage without altering claudin-1 distribution in the basal compartment. Moreover, NO increased by LMWF induce open of complexes junctions and release the germ cells of the adluminal compartment to the seminiferous tubule.(AU)


Assuntos
Animais , Masculino , Peptídeos , Epitélio Seminífero , Venenos de Serpentes , Espermatogênese , Bothrops , Produtos Biológicos
18.
Data Brief ; 25: 104180, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31321270

RESUMO

Functional polymeric nanoparticles have attracted attention for different biomedical applications, including drug delivery. Poloxamers (PL), a synthetic copolymers of poly(ethyleneoxide)-b-poly(propylene oxide)-b-poly(ethylene oxide), that exhibit thermoreversible behavior in aqueous solutions. Physicochemical properties of Oleic Acid-Poloxamer (OA-PL) organogel for intravaginal controlled Voriconazole (VRC) delivery were assessed using three different oils (isopropyl myristate - IPM, isopropyl palmitate - IPP, and oleic acid - OA, in order to select the most suitable oil phase for increasing the solubility of the drug and its dispersion in the final aqueous phase. Organogel structural organization was assessed by VRC partition coefficient, differential scanning calorimetry (DSC), rheological analysis, and drug release assay. These data are complementary to the research article entitled "Sodium alginate in oil-poloxamer organogels for intravaginal drug delivery: influence on structural parameters, drug release mechanisms, cytotoxicity and in vitro antifungal activity" - Materials Science and Engineering: C, 2019. 99: p. 1350-1361.

20.
Photodiagnosis Photodyn Ther ; 26: 316-323, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31042554

RESUMO

BACKGROUND: Candida albicans is an opportunistic fungus, an etiological agent of human infections, presenting high rates of morbidity and mortality. The resistance of C. albicans to conventional therapies has been reported due to the extensive use of conventional antifungals. Photodynamic antimicrobial chemotherapy (PACT) is a technique that combines a visible light with a specific wavelength and a photosensitizer, producing ROS and permanent damages in the treated cells. METHODS: In this work, the effects of PACT, using Methylene Blue (MB), as a photosensitizer, on C. albicans development were studied. RESULTS: Significant reduction in both cell growth and biofilm formation after PACT were observed, in a dependent manner on both MB concentration and fluence. In the presence of MB 0.02 mg/mL, it was observed inhibition in biofilm formation of ˜58, 70 and 74%, using fluences of 10, 20 and 30 J/cm2, respectively. Also, it was observed inhibition of 54, 66 and 55% in the presence of MB 0.01, 0.02 and 0.05 mg/mL, respectively in the viability of biofilm produced by C. albicans. The number of both yeast and filaments present in the structure of biofilm were reduced after PACT. Furthermore, PACT changed the growth kinetics of C. albicans. Interestingly, we demonstrated increase in the extent of lag phase and an alteration in the profile of the exponential phase after PACT. CONCLUSIONS: Taken together, these results indicate the potential PACT effects using MB to decrease the C. albicans development.


Assuntos
Antifúngicos/farmacologia , Biofilmes/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Azul de Metileno/farmacologia , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/farmacologia , Luz
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...