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1.
Braz. j. med. biol. res ; 56: e12484, 2023. tab
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1420761

RESUMO

Borderline personality disorder (BPD) is a severe psychiatric condition that affects up to 2.7% of the population and is highly linked to functional impairment and suicide. Despite its severity, there is a lack of knowledge about its pathophysiology. Studies show genetic influence and childhood violence as factors that may contribute to the development of BPD; however, the involvement of neuroinflammation in BPD remains poorly investigated. This article aimed to explore the pathophysiology of BPD according to the levels of brain-derived neurotrophic factor (BDNF), inflammatory cytokines, and oxidative stress substances that exacerbate neuronal damage. Few articles have been published on this theme. They show that patients with BPD have a lower level of BDNF and a higher level of tumor necrosis factor (TNF)-α and interleukin (IL)-6 in peripheral blood, associated with increased plasma levels of oxidative stress markers, such as malondialdehyde and 8-hydroxy-2-deoxyguanosine. Therefore, more research on the topic is needed, mainly with a pre-clinical and clinical focus.

2.
Braz. j. med. biol. res ; 55: e11721, 2022. tab
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1355920

RESUMO

The use of bladder antimuscarinics is very common in the elderly. However, recent population-based studies that assessed the use of anticholinergics or bladder antimuscarinics showed an increased risk of dementia when these drugs were used for a prolonged period. Several of these population-based studies included patients who used solifenacin, which is a bladder antimuscarinic released in 2005 with the prospect of being a more selective antimuscarinic for M3 receptors (M3R), which could make it a safer drug when trying to avoid unwanted effects of older bladder antimuscarinics such as oxybutynin, especially with regard to changes in cognition. Since the various bladder antimuscarinics have distinct pharmacological characteristics, such as in the ability to penetrate the blood-brain barrier, in selectivity for muscarinic receptors, and in brain efflux mechanisms, their effects on the central nervous system (CNS) may vary. Solifenacin was the drug selected in this review, which aims to describe the results of several articles published in recent years reporting the effects of solifenacin on cognition or the risk of dementia development. Although preclinical studies show that solifenacin can also act on brain M1 receptors (M1R), short-term clinical studies have shown it to be safe for cognition. However, there are no long-term randomized studies that prove the safety of this drug for the CNS. Thus, until the safety of solifenacin has been established by long-term studies, it seems advisable to avoid prolonged use of this drug in elderly patients.

3.
Braz. j. med. biol. res ; 54(2): e10107, 2021. graf
Artigo em Inglês | LILACS, ColecionaSUS | ID: biblio-1142578

RESUMO

Ketamine (KET) is an N-methyl-D-aspartate (NMDA) antagonist with rapid and long-lasting antidepressant effects, but how the drug shows its sustained effects is still a matter of controversy. The objectives were to evaluate the mechanisms for KET rapid (30 min) and long-lasting (15 and 30 days after) antidepressant effects in mice. A single dose of KET (2, 5, or 10 mg/kg, po) was administered to male Swiss mice and the forced swim test (FST) was performed 30 min, 15, or 30 days later. Imipramine (IMI, 30 mg/kg, ip), a tricyclic antidepressant drug, was used as reference. The mice were euthanized, separated into two time-point groups (D1, first day after KET injection; D30, 30 days later), and brain sections were processed for glycogen synthase kinase-3 (GSK-3), histone deacetylase (HDAC), brain-derived neurotrophic factor (BDNF), and glial fibrillary acidic protein (GFAP) immunohistochemical assays. KET (5 and 10 mg/kg) presented rapid and long-lasting antidepressant-like effects. As expected, the immunoreactivities for brain GSK-3 and HDAC decreased compared to control groups in all areas (striatum, DG, CA1, CA3, and mainly pre-frontal cortex, PFC) after KET injection. Increases in BDNF immunostaining were demonstrated in the PFC, DG, CA1, and CA3 areas at D1 and D30 time-points. GFAP immunoreactivity was also increased in the PFC and striatum at both time-points. In conclusion, KET changed brain BDNF and GFAP expressions 30 days after a single administration. Although neuroplasticity could be involved in the observed effects of KET, more studies are needed to explain the mechanisms for the drug's sustained antidepressant-like effects.


Assuntos
Animais , Masculino , Coelhos , Encéfalo/efeitos dos fármacos , Encéfalo/enzimologia , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Ketamina/farmacologia , Antidepressivos/farmacologia , Astrócitos , Quinase 3 da Glicogênio Sintase , Modelos Animais de Doenças , Proteína Glial Fibrilar Ácida , Histona Desacetilases
4.
Braz. j. med. biol. res ; 48(11): 953-964, Nov. 2015. tab, graf
Artigo em Inglês | LILACS | ID: lil-762901

RESUMO

Cocos nucifera (L.) (Arecaceae) is commonly called the “coconut tree” and is the most naturally widespread fruit plant on Earth. Throughout history, humans have used medicinal plants therapeutically, and minerals, plants, and animals have traditionally been the main sources of drugs. The constituents of C. nucifera have some biological effects, such as antihelminthic, anti-inflammatory, antinociceptive, antioxidant, antifungal, antimicrobial, and antitumor activities. Our objective in the present study was to review the phytochemical profile, pharmacological activities, and toxicology of C. nucifera to guide future preclinical and clinical studies using this plant. This systematic review consisted of searches performed using scientific databases such as Scopus, Science Direct, PubMed, SciVerse, and Scientific Electronic Library Online. Some uses of the plant were partially confirmed by previous studies demonstrating analgesic, antiarthritic, antibacterial, antipyretic, antihelminthic, antidiarrheal, and hypoglycemic activities. In addition, other properties such as antihypertensive, anti-inflammatory, antimicrobial, antioxidant, cardioprotective, antiseizure, cytotoxicity, hepatoprotective, vasodilation, nephroprotective, and anti-osteoporosis effects were also reported. Because each part of C. nucifera has different constituents, the pharmacological effects of the plant vary according to the part of the plant evaluated.


Assuntos
Animais , Humanos , Anti-Infecciosos/farmacologia , Cocos/química , Fitoterapia , Extratos Vegetais/farmacologia , Substâncias Protetoras/farmacologia , Analgésicos/farmacologia , Anti-Inflamatórios/farmacologia , Anticonvulsivantes/farmacologia , Anti-Hipertensivos/farmacologia , Osso e Ossos/efeitos dos fármacos , Cocos/toxicidade , Hipoglicemiantes/farmacologia
5.
Braz. j. med. biol. res ; 48(1): 57-64, 01/2015. tab, graf
Artigo em Inglês | LILACS | ID: lil-730434

RESUMO

Hoodia gordonii is a plant species used traditionally in southern Africa to suppress appetite. Recently, it has been associated with a significant increase in blood pressure and pulse rate in women, suggesting sympathomimetic activity. The present study investigated the possible antidepressant-like effects of acute and repeated (15 days) administration of H. gordonii extract (25 and 50 mg/kg, po) to mice exposed to a forced swimming test (FST). Neurochemical analysis of brain monoamines was also carried out to determine the involvement of the monoaminergic system on these effects. Acute administration of H. gordonii decreased the immobility of mice in the FST without accompanying changes in general activity in the open-field test during acute treatment, suggesting an antidepressant-like effect. The anti-immobility effect of H. gordonii was prevented by pretreatment of mice with PCPA [an inhibitor of serotonin (5-HT) synthesis], NAN-190 (a 5-HT1A antagonist), ritanserin (a 5-HT2A/2C antagonist), ondansetron (a 5-HT3A antagonist), prazosin (an α1-adrenoceptor antagonist), SCH23390 (a D1 receptor antagonist), yohimbine (an α2-adrenoceptor antagonist), and sulpiride (a D2 receptor antagonist). A significant increase in 5-HT levels in the striatum was detected after acute administration, while 5-HT, norepinephrine and dopamine were significantly elevated after chronic treatment. Results indicated that H. gordonii possesses antidepressant-like activity in the FST by altering the dopaminergic, serotonergic, and noradrenergic systems.

6.
Braz. j. med. biol. res ; 45(3): 179-186, Mar. 2012. ilus, tab
Artigo em Inglês | LILACS | ID: lil-618054

RESUMO

Prenatal immune challenge (PIC) in pregnant rodents produces offspring with abnormalities in behavior, histology, and gene expression that are reminiscent of schizophrenia and autism. Based on this, the goal of this article was to review the main contributions of PIC models, especially the one using the viral-mimetic particle polyriboinosinic-polyribocytidylic acid (poly-I:C), to the understanding of the etiology, biological basis and treatment of schizophrenia. This systematic review consisted of a search of available web databases (PubMed, SciELO, LILACS, PsycINFO, and ISI Web of Knowledge) for original studies published in the last 10 years (May 2001 to October 2011) concerning animal models of PIC, focusing on those using poly-I:C. The results showed that the PIC model with poly-I:C is able to mimic the prodrome and both the positive and negative/cognitive dimensions of schizophrenia, depending on the specific gestation time window of the immune challenge. The model resembles the neurobiology and etiology of schizophrenia and has good predictive value. In conclusion, this model is a robust tool for the identification of novel molecular targets during prenatal life, adolescence and adulthood that might contribute to the development of preventive and/or treatment strategies (targeting specific symptoms, i.e., positive or negative/cognitive) for this devastating mental disorder, also presenting biosafety as compared to viral infection models. One limitation of this model is the incapacity to model the full spectrum of immune responses normally induced by viral exposure.


Assuntos
Animais , Feminino , Camundongos , Gravidez , Ratos , Modelos Animais de Doenças , Polinucleotídeos , Efeitos Tardios da Exposição Pré-Natal/imunologia , Esquizofrenia/imunologia , Esquizofrenia/etiologia
7.
Braz. j. med. biol. res ; 37(12): 1839-1846, Dec. 2004. ilus, tab
Artigo em Inglês | LILACS | ID: lil-388052

RESUMO

We studied the effects of ethanol on concentrations of noradrenaline (NE), dopamine (DA) and serotonin (5-HT) and their metabolites in rat hippocampus and striatum. Ethanol (2 or 4 g/kg, po, from a 20 percent aqueous solution) was administered daily to male Wistar rats (4-13 per group) for 30 days and animals were sacrificed 30 min or 48 h after the last administration. Monoamines were measured by HPLC and considered significant at P < 0.05. A 47 percent increase in 5-HT levels was observed in the hippocampus with 4 g/kg ethanol in the 30-min protocol. Ethanol (2 and 4 g/kg) decreased DA (2114.5 ± 126.4 and 1785.1 ± 234.2 ng/g wet tissue, respectively) and 3,4-dihydroxyphenylacetic acid (DOPAC, 1477.6 ± 132.1 and 1218.8 ± 271.7 ng/g wet tissue, respectively) levels, while the higher dose also decreased NE (159.8 ± 13.5), 5-HT (228.0 ± 46.8) and 5-hydroxy-3-indoleacetic acid (5-HIAA, 304.4 ± 37.2 ng/g wet tissue), in the striatum after a 48-h withdrawal as compared to controls (DA: 3063.9 ± 321.3; DOPAC: 2379.6 ± 256.0; NE: 292.8 ± 50.2; 5-HT: 412.4 ± 36.2; 5-HIAA: 703.9 ± 61.4 ng/g wet tissue). In the 30-min protocol, ethanol (2 or 4 g/kg) decreased striatal NE (66 and 70 percent) and DA (50 and 36 percent) levels. On the other hand, increases were seen in 5-HIAA (146 and 153 percent) and 5-HT (59 and 86 percent) levels. Ethanol (2 g/kg, po) increased the homovanillic acid (HVA)/DA ratio (129 percent) in the striatum in the 30-min protocol, while at the higher dose it increased the HVA/DA ratio in the 48-h protocol (61 percent). These results indicate alterations in monoamines, mainly in the striatum, after chronic ethanol, which are influenced by dose and by the length of time after the last drug administration.


Assuntos
Animais , Masculino , Ratos , Catecolaminas/metabolismo , Depressores do Sistema Nervoso Central/farmacologia , Corpo Estriado/efeitos dos fármacos , Etanol/farmacologia , Hipocampo/efeitos dos fármacos , Depressores do Sistema Nervoso Central/administração & dosagem , Corpo Estriado/metabolismo , Dopamina/metabolismo , Etanol/administração & dosagem , Hipocampo/metabolismo , Norepinefrina/metabolismo , Ratos Wistar , Serotonina/metabolismo , Fatores de Tempo
8.
Braz. j. med. biol. res ; 36(4): 503-509, Apr. 2003. tab, graf
Artigo em Inglês | LILACS | ID: lil-331234

RESUMO

We studied the effects of ethanol on the levels of norepinephrine, dopamine, serotonin (5-HT) and their metabolites as well as on D1- and D2-like receptors in the rat striatum. Ethanol (2 or 4 g/kg, po) was administered daily by gavage to male Wistar rats and on the 7th day, 30 min or 48 h after drug administration, the striatum was dissected for biochemical assays. Monoamine and metabolite concentrations were measured by HPLC and D1- and D2-like receptor densities were determined by binding assays. Scatchard analyses showed decreases of 30 and 43 percent, respectively, in D1- and D2-like receptor densities and no change in dissociation constants (Kd) 48 h after the withdrawal of the dose of 4 g/kg. Ethanol, 2 g/kg, was effective only on the density of D2-like receptors but not on Kd of either receptor. Thirty minutes after the last ethanol injection (4 g/kg), decreases of D2 receptor density (45 percent) as well as of Kd values (34 percent) were detected. However, there was no significant effect on D1-like receptor density and a 46 percent decrease was observed in Kd. An increase in dopamine and 3,4-dihydroxyphenylacetic acid (DOPAC), a decrease in norepinephrine, and no alteration in 5-HT levels were demonstrated after 48-h withdrawal of 4 g/kg ethanol. Similar effects were observed in dopamine and DOPAC levels 30 min after drug administration. No alteration in norepinephrine concentration and a decrease in 5-HT levels were seen 30 min after ethanol (4 g/kg) administration. Our findings indicate the involvement of the monoaminergic system in the responses to ethanol


Assuntos
Humanos , Masculino , Ratos , Corpo Estriado , Receptores de Dopamina D1 , Receptores de Dopamina D2 , Monoaminas Biogênicas , Depressores do Sistema Nervoso Central , Cromatografia Líquida de Alta Pressão , Corpo Estriado , Dopamina , Etanol , Norepinefrina , Ratos Wistar , Receptores de Dopamina D1 , Receptores de Dopamina D2 , Serotonina
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