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The use of plants for medicinal purposes has a long history, however it is desirable a continuous evaluation seeking for complementary scientific evidences for their safe application. Species within the Kalanchoe genus are often referred to as "miracle leaf" due to their remarkable healing properties. Traditionally, these plants have been used to treat infections, inflammation, and cancer. Despite their widespread use, the identification of their active components remains incomplete. This study aimed to differentiate K. crenata (KC), K. marmorata (KM), and K. pinnata (KP) by conducting detailed histochemical and phytochemical analyses, and to assess their antioxidant capabilities. The investigation revealed significant differences between the species, highlighting the variability in phenolic (PC) and flavonoid contents (FC) and their distinct antioxidant effects. The KM demonstrated the greatest results (PC: 59.26±1.53â mgEqGA/g; FC: 12.63±0.91â mgEqCQ/g; DPPHâ (IC50): 110.66â ug/mL; ABTSâ + (IC50): 26.81â ug/mL; ORAC: 9.65±0.75â mmolTE) when compared to KC and KP. These findings underscore a new reference for research within the Kalanchoe genus.
Assuntos
Antioxidantes , Kalanchoe , Compostos Fitoquímicos , Extratos Vegetais , Kalanchoe/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Extratos Vegetais/isolamento & purificação , Compostos Fitoquímicos/química , Compostos Fitoquímicos/farmacologia , Compostos Fitoquímicos/isolamento & purificação , Antioxidantes/farmacologia , Antioxidantes/química , Antioxidantes/isolamento & purificação , Fenóis/química , Fenóis/farmacologia , Fenóis/isolamento & purificação , Água/química , Flavonoides/química , Flavonoides/farmacologia , Flavonoides/isolamento & purificação , Picratos/antagonistas & inibidores , Compostos de Bifenilo/antagonistas & inibidores , Compostos de Bifenilo/química , Folhas de Planta/químicaRESUMO
Parkinson's disease (PD) is a multifactorial disease, with genetic and environmental factors contributing to the disease onset. Classically, PD is a movement disorder characterized by the loss of dopaminergic neurons in the nigrostriatal pathway and intraneuronal aggregates mainly constituted of the protein α-synuclein. However, PD patients also display non-motor symptoms, including depression, which have been linked to functional abnormalities of non-dopaminergic neurons, including serotonergic and noradrenergic ones. Thus, through this comprehensive literature review, we shed light on the noradrenergic and serotonergic impairment linked to depression in PD, focusing on the putative involvement of inflammatory mechanisms.
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Ribopeaks is a rapid, sensitive, and economic web tool for bacterial identification based on m/z data from MALDI-TOF MS. To provide greater accuracy and robustness in the Ribopeaks analyzes we present an updated bacterial identification tool version, called Ribopeaks II (RPK-II). RPK-II contains a larger database, with r-protein data from fully sequenced bacterial genomes and optimized algorithms. Furthermore, this new version provides additional information about the identified bacterium, regarding antibiotic resistance.
Assuntos
Algoritmos , Bactérias , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por MatrizRESUMO
The most common features of Parkinson's disease (PD) are motor impairments, but many patients also present depression and memory impairment. Ketamine, an N-methyl-d-aspartate (NMDA) receptor antagonist, has been shown to be effective in patients with treatment-resistant major depression. Thus, the present study evaluated the action of ketamine on memory impairment and depressive-like behavior in an animal model of PD. Male Wistar rats received a bilateral infusion of 6 µg/side 6-hydroxydopamine (6-OHDA) into the substantia nigra pars compacta (SNc). Short-term memory was evaluated by the social recognition test, and depressive-like behaviors were evaluated by the sucrose preference and forced swimming tests (FST). Drug treatments included vehicle (i.p., once a week); ketamine (5, 10 and 15 mg/kg, i.p., once a week); and imipramine (20 mg/kg, i.p., daily). The treatments were administered 21 days after the SNc lesion and lasted for 28 days. The SNc lesion impaired short-term social memory, and all ketamine doses reversed the memory impairment and anhedonia (reduction of sucrose preference) induced by 6-OHDA. In the FST, 6-OHDA increased immobility, and all doses of ketamine and imipramine reversed this effect. The anti-immobility effect of ketamine was associated with an increase in swimming but not in climbing, suggesting a serotonergic effect. Ketamine and imipramine did not reverse the 6-OHDA-induced reduction in tyrosine hydroxylase immunohistochemistry in the SNc. In conclusion, ketamine reversed depressive-like behaviors and short-term memory impairment in rats with SNc bilateral lesions, indicating a promising profile for its use in PD patients.
Assuntos
Comportamento Animal/efeitos dos fármacos , Ketamina/farmacologia , Memória de Curto Prazo/efeitos dos fármacos , Doença de Parkinson/tratamento farmacológico , Animais , Depressão/tratamento farmacológico , Depressão/patologia , Modelos Animais de Doenças , Imipramina/farmacologia , Masculino , Oxidopamina/farmacologia , Parte Compacta da Substância Negra/efeitos dos fármacos , Ratos Wistar , Receptores de N-Metil-D-Aspartato/efeitos dos fármacosRESUMO
ABSTRACT Ferulic acid (FA) is a phenolic compound with well-known antioxidant potential that can be used as a promising anti-inflammatory and anti-cancer molecule. Furthermore, it has been reported to have neuroprotective activity. One of the main problems, which limit its clinical use, is its low bioavailability when administered orally. This limitation can be circumvented by changes in their structure and/or for preparing lipid-based formulations. The aim of this study was to synthesize a derivative of FA, the hexadecyl ferulate (HF). This compound would be more susceptible to pass through blood-brain barrier (BBB) due to its lipophilic character. The HF was obtained by Steglich esterification and yielded 76.77 ± 1.35%. Its structural characterization was performed by spectroscopic methods of Fourier-transformed infrared spectroscopy (FTIR) and nuclear magnetic resonance (NMR). FTIR spectrum of HF presented two typical bands of ester group, a C=O ester stretching band at 1725 cm-1 and a C-O stretching band at 1159 cm-1. The 1H and 13C spectral data confirmed the chemical structure of HF. Regarding the 13C NMR spectrum, HF showed a chemical shift at δ 167.39 ppm which corresponded to the carbonyl carbon of the ester group. Concerning the in vitro antioxidant potential, HF had equivalent or improved scavenger activity than FA leading to IC50 values of 0.083 ± 0.009 nmol.mL-1 and 0.027 ± 0.002 nmol.mL-1 in DPPH radical scavenging and ABTS radical cation decolorization assays, respectively. Further studies are required in order to investigate the antioxidant effect of HF in biological media.
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Besides being better known for causing motor impairments, Parkinson's disease (PD) can also cause many nonmotor symptoms, like depression and anxiety, which can cause significant loss of life quality and may not respond to regular drugs treatment. In this review, we discuss the depression in PD, based on data from studies in humans and rodents. Depression frequency seems higher in PD patients than in general population, despite high variation in data due to diagnosis disparities. Development of depression in PD seems more likely to be caused by the nigrostriatal pathway degeneration than as a consequence of the awareness of disease prognostic, and it seems to be related to dopaminergic, noradrenergic, and serotoninergic synapses deficits. The dopaminergic role could be more significant, since it can modulate the release of the others, and its depletion is progressive, due to the degenerative feature of PD. Highly regarded in major depression, serotonin can be depleted in rats after nigrostriatal damage, but data from human patients are more conflicting. Animal studies can help in understanding the neurobiological mechanisms of depression in PD and the pursuit for more effective drugs for its treatment, but they lack the complexity of the disease progression, especially the nondopaminergic degeneration.
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Background. Orthostatic hypotension (OH) is an important nonmotor manifestation of Parkinson's disease (PD). Changes in cerebrovascular reactivity may contribute to this manifestation and can be monitored using transcranial Doppler. Objective. To identify possible changes in cerebrovascular reactivity in patients with OH. Methods. Twenty-two individuals were selected and divided into three groups: with and without OH and controls. Transcranial Doppler was used to assess basal mean blood flow velocity, postapnea mean blood flow velocity, percentage increase in mean blood flow velocity, and cerebrovascular reactivity as measured by the breath-holding index. Results. PD patients had lower values of basal velocity (p = 0.019), postapnea velocity (p = 0.0015), percentage increase in velocity (p = 0.039), and breath-holding index (p = 0.04) than the controls. Patients with OH had higher values of basal velocity (p = 0.09) and postapnea velocity (p = 0.19) but lower values of percentage increase in velocity (p = 0.22) and breath-holding index (p = 0.32) than patients without OH. Conclusions. PD patients present with abnormalities in a compensatory mechanism that regulates cerebral blood flow. OH could be an indicator of these abnormalities.
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Parkinson's disease (PD) is an age-related neurodegenerative disorder characterized by the slow and progressive death of dopaminergic neurons in the (substantia nigra pars compact). Hypericum perforatum (H. perforatum) is a plant widely used as an antidepressant, that also presents antioxidant and anti-inflammatory properties. We evaluated the effects of H. perforatum on the turning behavior of rats submitted to a unilateral administration of 6-hydroxydopamine (6-OHDA) into the medial forebrain bundle as an animal model of PD. The animals were treated with H. perforatum (100, 200, or 400 mg/kg, v.o.) for 35 consecutive days (from the 28th day before surgery to the 7th day after). The turning behavior was evaluated at 7, 14 and 21 days after the surgery, and the turnings were counted as contralateral or ipsilateral to the lesion side. All tested doses significantly reduced the number of contralateral turns in all days of evaluation, suggesting a neuroprotective effect. However, they were not able to prevent the 6-OHDA-induced decrease of tyrosine hydroxylase expression in the lesioned striatum. We propose that H. perforatum may counteract the overexpression of dopamine receptors on the lesioned striatum as a possible mechanism for this effect. The present findings provide new evidence that H. perforatum may represent a promising therapeutic tool for PD.
A Doença de Parkinson é uma doença neurodegenerativa relacionada à idade, caracterizada pela morte lenta e progressiva de neurônios dopaminérgicos da substância negra pars compacta. O Hypericum perforatum (H. perforatum) é um fitoterápico utilizado como antidepressivo, apresentando propriedades antioxidantes, anti-inflamatórias e nootrópicas. Neste trabalho, avaliaram-se os efeitos do tratamento com H. perforatum no comportamento rotatório de ratos no modelo da doença de Parkinson induzido pela administração unilateral de 6-OHDA no feixe prosencefálico medial. Ratos Wistar machos foram tratados com H. perforatum (100, 200 ou 400 mg/kg, v.o.) por 35 dias (do 28º dia antes até o 7º dia após a lesão). As rotações ipsilaterais e contralaterais à lesão foram registradas no 7º, 14º e 21º dias após a cirurgia. As três doses de H. perforatum utilizadas reduziram o número de rotações contralaterais, indicando um possível efeito neuroprotetor da planta. Porém, o H. perforatum não impediu a redução na expressão da enzima tirosina hidroxilase no estriado lesionado, quantificada por Western blot. Propomos que o H. perforatum possa bloquear o aumento da expressão dos receptores dopaminérgicos no estriado lesionado com 6-OHDA. Entretanto, estudos adicionais são necessários para identificar o mecanismo exato pelo qual o H. perforatum reduziu o número de rotações contralaterais. Os resultados do presente estudo sugerem o H. perforatum como um potencial agente terapêutico para a doença de Parkinson.
Assuntos
Doença de Parkinson/diagnóstico , Hypericum , Oxidopamina/análise , Fármacos Neuroprotetores , FitoterapiaRESUMO
RATIONALE: Aversively motivated learning is more poorly understood than appetitively motivated learning in many aspects, including the role of dopamine receptors in different regions of the striatum. OBJECTIVES: The present study investigated the roles of the D1-like DA receptors in the nucleus accumbens (NAc) and dorsolateral striatum (DLS) on learning and performance of conditioned avoidance responses (CARs). METHODS: Adult male Wistar rats received intraperitoneal (i.p.), intra-NAc, or intra-DLS injections of the D1 dopamine receptor agonist SKF 81297 or the D1 receptor antagonist SCH 23390 20 min before or immediately after a training session in the CAR task two-way active avoidance, carried out 24 h before a test session. RESULTS: Pre-training administration of SCH 23390, but not SKF 81297, caused a significant decrease in the number of CARs in the test, but not in the training session, when injected into the DLS, or in either session when injected into the NAc. It also caused a significant increase in the number of escape failures in the training session when injected into the NAc. Systemic administration caused a combination of these effects. Post-training administrations of these drugs caused no significant effect. CONCLUSIONS: The results suggest that the D1-like receptors in the NAc and DLS play important, though different, roles in learning and performance of CAR.
Assuntos
Aprendizagem da Esquiva/fisiologia , Condicionamento Psicológico/fisiologia , Corpo Estriado/fisiologia , Núcleo Accumbens/fisiologia , Receptores de Dopamina D1/fisiologia , Animais , Aprendizagem da Esquiva/efeitos dos fármacos , Condicionamento Psicológico/efeitos dos fármacos , Corpo Estriado/efeitos dos fármacos , Antagonistas de Dopamina/farmacologia , Masculino , Núcleo Accumbens/efeitos dos fármacos , Ratos , Ratos Wistar , Receptores de Dopamina D1/antagonistas & inibidoresRESUMO
The multiple memory systems theory proposes that the hippocampus and the dorsolateral striatum are the core structures of the spatial/relational and stimulus-response (S-R) memory systems, respectively. This theory is supported by double dissociation studies showing that the spatial and cue (S-R) versions of the Morris water maze are impaired by lesions in the dorsal hippocampus and dorsal striatum, respectively. In the present study we further investigated whether adult male Wistar rats bearing double and bilateral electrolytic lesions in the dorsal hippocampus and dorsolateral striatum were as impaired as rats bearing single lesions in just one of these structures in learning both versions of the water maze. Such a prediction, based on the multiple memory systems theory, was not confirmed. Compared to the controls, the animals with double lesions exhibited no improvement at all in the spatial version and learned the cued version very slowly. These results suggest that, instead of independent systems competing for holding control over navigational behaviour, the hippocampus and dorsal striatum both play critical roles in navigation based on spatial or cue-based strategies.