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1.
PEC Innov ; 4: 100262, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38375351

RESUMO

Objective: Health literacy is a critical health determinant, for which few computerized, self-administered assessments exist. This study adapted and tested the reliability of the Newest Vital Sign© (NVS) as a computerized, self-administered health literacy screener. Methods: Phase one involved 33 participants to create response options for a computerized, self-administered NVS (C-NVS). Phase two was a randomized crossover trial to test the consistency of C-NVS and original, interviewer-administered NVS (I-NVS) scores in 89 participants. Results: Linear mixed-effects regression model results showed a significant carryover effect (p < .001). Crossover trial data from time 1 showed that participants who initially received the C-NVS had significantly higher average scores (M = 5.7, SD = 0.6) than participants who received the I-NVS (M = 4.5, SD = 1.5; t(87) = 5.25, p < .001). Exploratory analysis results showed that when the washout period was longer than 33 days (75th percentile) the carryover effect was not statistically significant (p = .077). Conclusion and innovation: Findings suggest learning can occur when health literacy screeners are administered more than once in less than a month's time and computerized, self-administered health literacy screeners may produce ceiling effects. A universal precautions approach to health literacy therefore remains germane.

2.
Autism ; 26(6): 1460-1476, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-34657479

RESUMO

LAY ABSTRACT: Caregiver strain is the adverse impact that parents of children with emotional and behavioral issues including autism often experience (e.g. negative consequences of caregiving such as financial strain and social isolation; negative feelings that are internal to the caregiver such as worry and guilt; and negative feelings directed toward the child such as anger or resentment). This study showed that on average caregiver strain did not significantly change in North American parents of children with autism during a 2-year period. Improved caregiver strain was linked to improved child functioning and behavior. Routine assessment of caregiver strain and referral to evidence-based programming and supports may help alleviate some of the burden that families of children with autism commonly experience.


Assuntos
Transtorno do Espectro Autista , Transtorno Autístico , Transtorno Autístico/psicologia , Transtorno Autístico/terapia , Cuidadores/psicologia , Criança , Humanos , América do Norte , Pais/psicologia , Sistema de Registros
3.
Aquaculture ; 541: 736772, 2021 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-34471330

RESUMO

Mycoplasmas are the smallest autonomously self-replicating life form on the planet. Members of this bacterial genus are known to parasitise a wide array of metazoans including vertebrates. Whilst much research has been significant targeted at parasitic mammalian mycoplasmas, very little is known about their role in other vertebrates. In the current study, we aim to explore the biology of mycoplasmas in Atlantic Salmon, a species of major significance for aquaculture, including cellular niche, genome size structure and gene content. Using fluorescent in-situ hybridisation (FISH), mycoplasmas were targeted in epithelial tissues across the digestive tract (stomach, pyloric caecum and midgut) from different development stages (eggs, parr, subadult) of farmed Atlantic salmon (Salmo salar), and we present evidence for an intracellular niche for some of the microbes visualised. Via shotgun metagenomic sequencing, a nearly complete, albeit small, genome (~0.57 MB) as assembled from a farmed Atlantic salmon subadult. Phylogenetic analysis of the recovered genome revealed taxonomic proximity to other salmon derived mycoplasmas, as well as to the human pathogen Mycoplasma penetrans (~1.36 Mb). We annotated coding sequences and identified riboflavin pathway encoding genes and sugar transporters, the former potentially consistent with micronutrient provisioning in salmonid development. Our study provides insights into mucosal adherence, the cellular niche and gene catalog of Mycoplasma in the gut ecosystem of the Atlantic salmon, suggesting a high dependency of this minimalist bacterium on its host. Further study is required to explore and functional role of Mycoplasma in the nutrition and development of its salmonid host.

4.
Aging Cell ; 17(2)2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29405550

RESUMO

Moment-to-moment adjustment of cerebral blood flow (CBF) via neurovascular coupling has an essential role in maintenance of healthy cognitive function. In advanced age, increased oxidative stress and cerebromicrovascular endothelial dysfunction impair neurovascular coupling, likely contributing to age-related decline of higher cortical functions. There is increasing evidence showing that mitochondrial oxidative stress plays a critical role in a range of age-related cellular impairments, but its role in neurovascular uncoupling remains unexplored. This study was designed to test the hypothesis that attenuation of mitochondrial oxidative stress may exert beneficial effects on neurovascular coupling responses in aging. To test this hypothesis, 24-month-old C57BL/6 mice were treated with a cell-permeable, mitochondria-targeted antioxidant peptide (SS-31; 10 mg kg-1  day-1 , i.p.) or vehicle for 2 weeks. Neurovascular coupling was assessed by measuring CBF responses (laser speckle contrast imaging) evoked by contralateral whisker stimulation. We found that neurovascular coupling responses were significantly impaired in aged mice. Treatment with SS-31 significantly improved neurovascular coupling responses by increasing NO-mediated cerebromicrovascular dilation, which was associated with significantly improved spatial working memory, motor skill learning, and gait coordination. These findings are paralleled by the protective effects of SS-31 on mitochondrial production of reactive oxygen species and mitochondrial respiration in cultured cerebromicrovascular endothelial cells derived from aged animals. Thus, mitochondrial oxidative stress contributes to age-related cerebromicrovascular dysfunction, exacerbating cognitive decline. We propose that mitochondria-targeted antioxidants may be considered for pharmacological microvascular protection for the prevention/treatment of age-related vascular cognitive impairment (VCI).


Assuntos
Antioxidantes/metabolismo , Disfunção Cognitiva/fisiopatologia , Células Endoteliais/metabolismo , Mitocôndrias/metabolismo , Acoplamento Neurovascular/genética , Peptídeos/metabolismo , Envelhecimento , Animais , Masculino , Camundongos
5.
Aging Cell ; 16(3): 469-479, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28295976

RESUMO

Clinical and experimental studies show that aging exacerbates hypertension-induced cerebral microhemorrhages (CMHs), which progressively impair neuronal function. There is growing evidence that aging promotes insulin-like growth factor 1 (IGF-1) deficiency, which compromises multiple aspects of cerebromicrovascular and brain health. To determine the role of IGF-1 deficiency in the pathogenesis of CMHs, we induced hypertension in mice with liver-specific knockdown of IGF-1 (Igf1f/f  + TBG-Cre-AAV8) and control mice by angiotensin II plus l-NAME treatment. In IGF-1-deficient mice, the same level of hypertension led to significantly earlier onset and increased incidence and neurological consequences of CMHs, as compared to control mice, as shown by neurological examination, gait analysis, and histological assessment of CMHs in serial brain sections. Previous studies showed that in aging, increased oxidative stress-mediated matrix metalloprotease (MMP) activation importantly contributes to the pathogenesis of CMHs. Thus, it is significant that hypertension-induced cerebrovascular oxidative stress and MMP activation were increased in IGF-1-deficient mice. We found that IGF-1 deficiency impaired hypertension-induced adaptive media hypertrophy and extracellular matrix remodeling, which together with the increased MMP activation likely also contributes to increased fragility of intracerebral arterioles. Collectively, IGF-1 deficiency promotes the pathogenesis of CMHs, mimicking the aging phenotype, which likely contribute to its deleterious effect on cognitive function. Therapeutic strategies that upregulate IGF-1 signaling in the cerebral vessels and/or reduce microvascular oxidative stress, and MMP activation may be useful for the prevention of CMHs, protecting cognitive function in high-risk elderly patients.


Assuntos
Envelhecimento/metabolismo , Hemorragia Cerebral/metabolismo , Matriz Extracelular/metabolismo , Hipertensão/metabolismo , Fator de Crescimento Insulin-Like I/deficiência , Envelhecimento/patologia , Angiotensina II/administração & dosagem , Animais , Hemorragia Cerebral/induzido quimicamente , Hemorragia Cerebral/etiologia , Hemorragia Cerebral/fisiopatologia , Modelos Animais de Doenças , Matriz Extracelular/patologia , Marcha , Hipertensão/induzido quimicamente , Hipertensão/complicações , Hipertensão/fisiopatologia , Bombas de Infusão Implantáveis , Fator de Crescimento Insulin-Like I/genética , Masculino , Metaloproteinases da Matriz/genética , Metaloproteinases da Matriz/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , NG-Nitroarginina Metil Éster/administração & dosagem , Estresse Oxidativo , Fenótipo , Desempenho Psicomotor
6.
J Gerontol A Biol Sci Med Sci ; 72(9): 1295-1301, 2017 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-27927762

RESUMO

OBJECTIVE: To test the hypothesis that urinary incontinence (UI) is associated with incident parkinsonism in older adults. METHODS: We used data from 2,617 older persons without dementia. Assessment included baseline self-report UI and annual structured exam which assessed parkinsonian signs, motor performances, cognitive function, and self-report disabilities. We used a series of Cox proportional hazards models to examine the association of UI with parkinsonism and adverse health outcomes and a mixed-effect model to examine the association of UI with the annual rate of cognitive decline. In decedents, regression models were used to examine if UI proximate to death was related to postmortem indices of neuropathologies. RESULTS: At baseline, more than 45% of participants reported some degree of UI. Over an average of nearly 8 years of follow-up, UI was associated with incident parkinsonism (hazard ratio [HR] = 1.07, 95% CI = 1.02, 1.12), death (HR = 1.07, 95% CI = 1.03, 1.11), incident ADL disability (HR = 1.11, 95% CI = 1.07, 1.16), and incident mobility disability (HR = 1.07, 95% CI = 1.02, 1.13). UI was not related to incident MCI (HR = 1.02, 95% CI = 0.97, 1.07), incident AD dementia (HR = 1.00, 95% CI = 0.95, 1.05) or to the rate of cognitive decline (Estimate = -.002, standard error = .002, p = .167). In 1,024 decedents with brain autopsy, UI proximate to death was related to PD pathology (Lewy body pathology and nigral neuronal loss), but not Alzheimer's disease pathology or other age-related neuropathologies. CONCLUSION: UI in older adults is associated with incident parkinsonism and may identify older adults at risk for accumulating PD brain pathology.


Assuntos
Doença de Parkinson/epidemiologia , Transtornos Parkinsonianos/epidemiologia , Incontinência Urinária/epidemiologia , Idoso , Idoso de 80 Anos ou mais , Autopsia , Comorbidade , Feminino , Avaliação Geriátrica , Humanos , Incidência , Estudos Longitudinais , Masculino , Fatores de Risco , Estados Unidos/epidemiologia
7.
Aging Cell ; 14(6): 1034-44, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26172407

RESUMO

Aging is associated with marked deficiency in circulating IGF-1, which has been shown to contribute to age-related cognitive decline. Impairment of moment-to-moment adjustment of cerebral blood flow (CBF) via neurovascular coupling is thought to play a critical role in the genesis of age-related cognitive impairment. To establish the link between IGF-1 deficiency and cerebromicrovascular impairment, neurovascular coupling mechanisms were studied in a novel mouse model of IGF-1 deficiency (Igf1(f/f) -TBG-Cre-AAV8) and accelerated vascular aging. We found that IGF-1-deficient mice exhibit neurovascular uncoupling and show a deficit in hippocampal-dependent spatial memory test, mimicking the aging phenotype. IGF-1 deficiency significantly impaired cerebromicrovascular endothelial function decreasing NO mediation of neurovascular coupling. IGF-1 deficiency also impaired glutamate-mediated CBF responses, likely due to dysregulation of astrocytic expression of metabotropic glutamate receptors and impairing mediation of CBF responses by eicosanoid gliotransmitters. Collectively, we demonstrate that IGF-1 deficiency promotes cerebromicrovascular dysfunction and neurovascular uncoupling mimicking the aging phenotype, which are likely to contribute to cognitive impairment.


Assuntos
Envelhecimento/genética , Circulação Cerebrovascular/fisiologia , Transtornos Cognitivos/genética , Fator de Crescimento Insulin-Like I/genética , Acoplamento Neurovascular/genética , Envelhecimento/fisiologia , Animais , Encéfalo/fisiologia , Transtornos Cognitivos/fisiopatologia , Modelos Animais de Doenças , Fator de Crescimento Insulin-Like I/deficiência , Fator de Crescimento Insulin-Like I/metabolismo , Masculino , Aprendizagem em Labirinto/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Microvasos/fisiologia , Óxido Nítrico/biossíntese , Memória Espacial/fisiologia
8.
PLoS One ; 8(8): e70888, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23967129

RESUMO

Argentine ants (Linepithema humile) live in groups of nests connected by trails to each other and to stable food sources. In a field study, we investigated whether some ants recruit directly from established, persistent trails to food sources, thus accelerating food collection. Our results indicate that Argentine ants recruit nestmates to food directly from persistent trails, and that the exponential increase in the arrival rate of ants at baits is faster than would be possible if recruited ants traveled from distant nests. Once ants find a new food source, they walk back and forth between the bait and sometimes share food by trophallaxis with nestmates on the trail. Recruiting ants from nearby persistent trails creates a dynamic circuit, like those found in other distributed systems, which facilitates a quick response to changes in available resources.


Assuntos
Formigas , Comportamento Animal , Ração Animal , Animais , Fatores de Tempo
9.
Indian J Pharm Sci ; 75(6): 635-41, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24591737

RESUMO

Stroke is the third cause of death and the first of permanent adult disability. Pretreatment with policosanol and atorvastatin has been effective in experimental models of cerebral ischaemia in rodents. The objective was to compare the therapeutic effects of policosanol and atorvastatin in a model of global cerebral ischaemia in gerbils. Gerbils were distributed into seven groups, a negative control and six with ischaemia-reperfusion-induced global cerebral ischemia (one vehicle positive control, two policosanol (100 and 200 mg/kg), two atorvastatin (10 and 20 mg/kg) and one aspirin (60 mg/kg) group). Treatments were given 4 h after ischaemia induction. Effects on ischemia-reperfusion-induced symptoms, hyperlocomotion, damage of pyramidal hipoccampal neurons and increased plasma oxidative markers were investigated. Positive, not negative controls, exhibited clinical symptoms, hyperlocomotion, neuronal damage and increased plasma oxidative markers. Policosanol (100 and 200 mg/kg) reduced significantly ischemia-reperfusion-induced symptoms, the frequency of symptomatic animals, histological scores of neuronal damage and plasma oxidative markers as compared with the positive control group. Atorvastatin (10 and 20 mg/kg) decreased significantly the symptoms and histological scores, but unchanged the frequency of symptomatic gerbils and oxidative variables. Only the highest dose of policosanol (200 mg/kg) and atorvastatin (20 mg/kg) reduced significantly ischemia reperfusion-induced hyperlocomotion, policosanol being the most effective. Aspirin 60 mg/kg lowered significantly symptom score, the rate of symptomatic gerbils and hyperlocomotion versus the positive controls, but failed to modify oxidative parameters. In conclusion, postreperfusion treatment with policosanol and atorvastatin was effective for ameliorating symptoms, hyperlocomotion and neurological damage of hippocampal CA1 neurons in gerbils with ischemia-reperfusion-induced global cerebral ischemia, but only policosanol reduced increased plasma oxidative variables.

10.
Food Chem Toxicol ; 49(11): 2855-61, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21839798

RESUMO

D-004, a lipid extract of royal palm (Roystonea regia) fruits that contains a reproducible mixture of fatty acids, has been shown to prevent testosterone and phenylephrine-induced prostate hyperplasia in rodents. This study investigated the long-term oral toxicity of D-004 in rats. Rats from both sexes were randomized into four groups (20 rats sex/group): a control and three treated with D-004 (800, 1500 or 2000 mg/kg/day, respectively). At study completion, rats were sacrificed under anaesthesia. Determinations of blood biochemical and haematological parameters and organ weight were done. Also, necropsy and histopathological studies were performed. Four of 160 rats died before study completion. No clinical signs of toxicity were observed throughout the study. Food and water consumption, bodyweight, blood biochemical and haematological parameters, organ weight ratios and histopathological findings were similar in control and treated groups. The histological lesions found in treated animals are commonly present in this specie and strain according to literature and our historical data. In conclusion, long-term (12 months) oral treatment of rats with D-004 (800-2000 mg/kg/day) did not show evidences of D-004-related toxicity under our conditions. The highest dose tested (2000 mg/kg) was a no-observed adverse effect level in this study.


Assuntos
Arecaceae/química , Frutas/química , Extratos Vegetais/toxicidade , Administração Oral , Animais , Esquema de Medicação , Feminino , Masculino , Extratos Vegetais/administração & dosagem , Extratos Vegetais/química , Ratos , Ratos Sprague-Dawley
11.
Food Chem Toxicol ; 47(4): 687-92, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19056453

RESUMO

D-003, a mixture of high aliphatic primary acids purified from sugar cane wax, has shown cholesterol-lowering, anti-platelet and antioxidant effects. Previous data demonstrated that D-003 was not toxic or carcinogenic when given orally to Sprague-Dawley rats up to 1500 mg/kg. This study investigated the potential long-term oral carcinogenicity of D-003 in a second rodent species. OF1 mice of both sexes were randomized into 4 groups treated for 18 months: a vehicle control group and three groups treated with D-003 at 50, 500 and 1500 mg/kg, respectively, orally gavaged 6 days per week. Mortality, clinical symptoms, weight gain, food consumption, organ weight, blood indicators and tumour incidence did not show significant differences between control and treated groups. D-003 did not increase the frequency of neoplastic or non-neoplastic lesions with respect to the controls. Lesions observed in the study were consistent with spontaneous lesions reported for this specie. It can be concluded that D-003 did not result toxic or carcinogenic when given orally to OF1 mice for 18 months and that the highest dose was a NOAEL, consistent with results of the oral carcinogenicity study of D-003 in rats.


Assuntos
Ácidos Graxos/toxicidade , Neoplasias Experimentais/induzido quimicamente , Adenocarcinoma/induzido quimicamente , Animais , Testes de Carcinogenicidade , Feminino , Neoplasias Pulmonares/induzido quimicamente , Masculino , Camundongos
12.
Pharmazie ; 63(6): 486-8, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18604996

RESUMO

This study was done to determine the long-term effect of D-003 on bones of ovariectomized (ovx) rats distrib-uted in 4 groups: a false-operated and three groups of ovx rats: one treated with the vehicle and two with D-003 (5 and 250 mg/kg). D-003 significantly prevented, in a dose-dependent fashion, the trabecular bone volume (TBV), trabecular number (TbN) and trabecular thickness (TbTh) reduction induced in ovx rats and the increase of trabecular separation (TbSp) osteoclast number (OcN) and osteoclast surface (OcS/BS) increased in the positive controls versus the sham group. It is concluded that D-003 administered for 12 months prevented bone loss and decreased bone resorption in ovx rats, without evidences of impaired bone quality.


Assuntos
Conservadores da Densidade Óssea , Ácidos Graxos/farmacologia , Saccharum/química , Ceras/química , Animais , Reabsorção Óssea/tratamento farmacológico , Reabsorção Óssea/patologia , Osso e Ossos/patologia , Ácidos Graxos/química , Feminino , Peso Molecular , Osteoclastos/efeitos dos fármacos , Ovariectomia , Ratos , Ratos Sprague-Dawley , Malha Trabecular/efeitos dos fármacos
13.
Food Chem Toxicol ; 45(12): 2352-8, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17937974

RESUMO

D-003 is a mixture of high molecular weight sugarcane wax aliphatic primary acids with cholesterol-lowering, anti-platelet and antioxidant effects. This study investigated the long-term oral toxicity and carcinogenicity of D-003 in Sprague Dawley rats of both sexes, randomly distributed into four groups: a control group, treated only with the vehicle, and three treated with D-003 (50, 500 and 1500 mg/kg). All treatments were given orally for 24 months. Mortality (survival analysis), clinical symptoms, weight gain, food consumption, organ weights, time-to-tumour or tumour incidence data were not shown between group differences or trends. With the exception of serum cholesterol levels, lower in D-003-treated groups (500 and 1500 mg/kg) than in the controls, no other difference in blood indicators was found. D-003 did not increase the frequency of neoplastic and non-neoplastic lesions compared with the controls. The occurrence of all malignant and mammary tumours in D-003-treated females was lower than in the controls. The lesions observed were consistent with spontaneous lesions reported in this species. In conclusion, D-003 is not toxic or carcinogenic when given orally to Sprague Dawley rats up to 1500 mg/kg for 2 years, and 1500 mg/kg was a not-observable effect dose.


Assuntos
Anticolesterolemiantes/toxicidade , Ácidos Graxos/toxicidade , Inibidores da Agregação Plaquetária/toxicidade , Administração Oral , Animais , Anticolesterolemiantes/administração & dosagem , Anticolesterolemiantes/química , Testes de Carcinogenicidade , Ácidos Graxos/administração & dosagem , Ácidos Graxos/química , Feminino , Masculino , Peso Molecular , Inibidores da Agregação Plaquetária/administração & dosagem , Inibidores da Agregação Plaquetária/química , Ratos , Ratos Sprague-Dawley
14.
Drugs R D ; 7(4): 233-41, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16784248

RESUMO

BACKGROUND AND OBJECTIVE: Benign prostatic hyperplasia (BPH) is a non-malignant enlargement of the prostate that results in obstructive lower urinary tract symptoms. Saw palmetto (Serenoa repens), the dwarf American palm (Arecaceae family), is commonly used to treat BPH. The Cuban royal palm (Roystonea regia) also belongs to the Arecaceae family, and 200-400mg of D-004, a lipid extract from its fruits, administered orally for 14 days has been shown to prevent testosterone- but not dihydrotestosterone-induced prostatic hyperplasia in rats. D-004 (125-250 microg/mL) added to preparations of rat vas deferens caused a marked, dose-dependent and significant inhibition of noradrenaline-induced smooth muscle contraction, a response mediated through alpha(1)-adrenoceptors, and was more effective in these respects than Saw palmetto. However, the in vivo effects of D-004 and Saw palmetto on the hypertensive response induced by noradrenaline were modest (albeit significant), and neither treatment affected resting blood pressure or heart rate in rats. The differential effects of D-004 in in vitro and in vivo models could be related to a differential affinity for adrenoceptor subtypes or to different bioavailabilities in vascular and urogenital targets. Phenylephrine injected into rodents induces prostatic hyperplasia with all the characteristic morphological changes of the condition but does not result in enlargement of the prostate. Therefore, this phenylephrine-induced change in rat prostate tissue is called atypical prostatic hyperplasia. It serves as an in vivo model of prostatic hyperplasia induced by stimulation of alpha(1)-adrenoceptors. The objective of this study was to determine whether D-004 can inhibit induction of atypical prostatic hyperplasia by phenylephrine in rats. METHODS: Rats were randomly distributed into five groups (ten rats/group). One group was a negative control and received oral vehicle only. The other four groups were injected subcutaneously with phenylephrine (2 mg/kg): of these groups, one was a positive control receiving the vehicle, and the other three groups were treated with D-004 or Saw palmetto (both 400 mg/kg) or tamsulosin 0.4 mg/kg. All active treatments were given orally for 28 days. After completion of treatment, rats were placed unrestrained in metabolic cages and micturition studies were performed. The rats were later killed and their prostates removed and weighed. Prostate samples were processed for histological study, with histological changes being assessed according to a scoring system. Bodyweight was measured at baseline and at weekly intervals. RESULTS: Histological examination of positive control rats revealed features of atypical prostatic hyperplasia, with piling-up, papillary and cribiform patterns and budding-out of epithelial cells. Micturition assessment revealed that phenylephrine significantly lowered both the total volume of urine in 1 hour and the volume per micturition; the latter was considered the main efficacy variable. D-004 and Saw palmetto extracts significantly prevented this reduction in volume per micturition by 70.5% and 68.6%, respectively, while tamsulosin totally abolished the reduction in micturition induced by phenylephrine (100% inhibition). Tamsulosin, D-004 and Saw palmetto significantly reduced the histological changes of atypical prostatic hyperplasia induced by phenylephrine by 73.1%, 61.2% and 50.0%, respectively. CONCLUSIONS: Administration of D-004 resulted in marked and significant prevention of phenylephrine-induced impairment of micturition and histological changes in rat prostate. These findings indicate that, in vivo, D-004 effectively opposes these responses to phenylephrine, which are mediated through urogenital alpha(1)-adrenoceptors. In this respect, D-004 was moderately more effective than Saw palmetto, a phytotherapeutic standard used to treat BPH, but less effective than tamsulosin, a selective alpha(1A)-adrenoceptor antagonist.


Assuntos
Arecaceae/química , Extratos Vegetais/uso terapêutico , Hiperplasia Prostática/tratamento farmacológico , Animais , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Frutas/química , Masculino , Fenilefrina/química , Extratos Vegetais/administração & dosagem , Extratos Vegetais/isolamento & purificação , Hiperplasia Prostática/induzido quimicamente , Hiperplasia Prostática/patologia , Ratos , Ratos Sprague-Dawley
15.
Drugs Exp Clin Res ; 31(3): 101-8, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16033248

RESUMO

D-004 is a lipid extract obtained from Cuban royal palm (Rosytonea regia) fruits, consisting of a mixture of fatty acids and esters. D-004 has shown protective effects on prostate hyperplasia induced by testosterone in rodents. We report the results of two studies investigating the acute and subchronic oral toxicity of D004 in rats. Oral acute toxicity of D-004 (2,000 mg/kg) was investigated in Sprague Dawley rats according to the acute toxic class method, and the results showed that D-004 oral acute toxicity was practically absent, being defined as unclassified. In the subchronic study, rats were orally treated with D-004 at 500, 1,000 and 2,000 mg/kg for 90 days. No evidence of treatment-related toxicity was detected. Thus, analysis of body weight gain, clinical observations, blood biochemistry, hematology, organ weight ratios and histopathological data did not show significant differences between control and treated groups. We conclude that D-004 orally administered to rats was safe and that no drug-related toxicity was detected even at the highest dose investigated in both acute and subchronic (2,000 mg/kg) studies. Thus, this dose can be considered as a nonobservable-effect dose in rats.


Assuntos
Arecaceae/química , Lipídeos/química , Extratos Vegetais/toxicidade , Testes de Toxicidade Aguda , Testes de Toxicidade Crônica , Administração Oral , Animais , Feminino , Frutas/química , Masculino , Nível de Efeito Adverso não Observado , Hiperplasia Prostática/prevenção & controle , Ratos , Ratos Sprague-Dawley
16.
Drugs Exp Clin Res ; 31(5-6): 181-91, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16425974

RESUMO

The mevalonate pathway is relevant in bone cells. Statins inhibit 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase, the key enzyme of this route, stimulating osteoblast differentiation and activity. Pravastatin increases bone formation markers in postmenopausal women and bone density in diabetics. D-003 is a mixture of high-molecular-weight acids purified from sugarcane wax which inhibits cholesterol biosynthesis through HMG-CoA reductase regulation, preventing bone loss in osteoporosis induced with ovariectomy and prednisolone in rats. We investigated the effects of D-003 (50 mg/kg) and pravastatin (20 mg/kg) orally administered for 12 weeks to ovariectomized rats. Female rats were randomized in four groups (10 rats/group): two control groups treated with the vehicle, one false-operated (sham) and another ovariectomized (positive control), while two other groups received D-003 or pravastatin. Bone resorption and formation was studied through histomorphometry and apoptosis through immunohistochemistry. D-003 and pravastatin significantly (p < 0.001) prevented the changes of trabecular bone versus ovariectomized rats and (p < 0.001) the increase of the surface and number of osteoclasts versus ovariectomized controls. D-003 and pravastatin, however, did not modify osteoblast surfaces, a bone formation marker D-003 and pravastatin increased osteoclast apoptosis and reduced (p < 0.05) osteoblast and osteocyte apoptosis versus ovariectomized controls; D-003 was more effective (p < 0.05) than pravastatin. In conclusion, D-003 (50 mg/kg) orally administered for 12 weeks prevented bone loss and bone resorption in ovariectomized rats, increasing osteoclast apoptosis. The preventive effects of D-003 on bone loss and resorption in ovariectomized rats are comparable to those of pravastatin. Both drugs inhibited osteoblast apoptosis but failed to change osteoblast surface. The effects of D-003 on bone cell apoptosis were greater than those of pravastatin. Therefore, D-003 could be used to prevent or treat bone loss in postmenopausal women, but further animal studies and clinical trials are required to confirm the clinical relevance of this potential effect.


Assuntos
Osso e Ossos/efeitos dos fármacos , Ácidos Graxos/farmacologia , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Osteoclastos/efeitos dos fármacos , Pravastatina/farmacologia , Saccharum , Animais , Apoptose , Reabsorção Óssea/prevenção & controle , Osso e Ossos/citologia , Feminino , Osteoclastos/citologia , Ovariectomia , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley
17.
Int J Tissue React ; 27(4): 213-22, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16440587

RESUMO

The mevalonate pathway is crucial for osteoclast function. D-003 is a mixture of high molecular weight acids purified from sugarcane wax, which inhibits cholesterol biosynthesis through HMG-CoA reductase regulation. D-003 administered at 50 and 200 mg/kg for 12 weeks prevented bone loss in ovariectomized rats, increasing osteoclast apoptosis. The present study investigated whether the effects of D-003 on bone resorption and osteoclast apoptosis are dose-dependent. Rats were randomized into seven groups (10 rats/group): two control groups orally treated with the vehicle, one false-operated (sham) and another ovariectomized group (positive control), while another four groups received D-003 (5, 25, 50 and 200 mg/kg). The effects on bone resorption and formation were studied through histomorphometry and the effects on apoptosis through immunohistochemistry. D-003 (5-200 mg/kg) dose-dependently and significantly prevented (p < 0.001) changes in trabecular bone and increase in osteoclast surface and number versus ovariectomized controls, leaving osteoblast surfaces unchanged. Across the dose range, D-003 significantly increased (p < 0.05) osteoclast apoptosis in a dose-dependent manner and reduced (p < 0.05) osteoblast and osteocyte apoptosis versus ovariectomized controls, but these effects did not show dose dependence. In conclusion, D-003 (5-200 mg/kg) orally administered at for 12 weeks prevented bone loss and bone resorption and increased osteoclast apoptosis in ovariectomized rats in a dose-dependent manner. These results are consistent with previous data, showing that D-003 administered at relatively low doses prevents bone loss induced with ovariectomy, which could be useful to prevent or treat bone loss in postmenopausal women. Further experimental and clinical studies, however, are needed to confirm these findings.


Assuntos
Apoptose/efeitos dos fármacos , Osso e Ossos/citologia , Osso e Ossos/efeitos dos fármacos , Ácidos Graxos/farmacologia , Ovariectomia , Saccharum , Ceras/química , Animais , Relação Dose-Resposta a Droga , Ácidos Graxos/administração & dosagem , Feminino , Peso Molecular , Ratos , Ratos Sprague-Dawley
18.
Int J Tissue React ; 27(4): 203-11, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16440586

RESUMO

Benign prostatic hyperplasia (BPH) is the nonmalignant, uncontrolled growth of prostate gland cells and stroma leading to difficulty in urinating. Lipid extracts from Saw palmetto (Arecaceae) fruits are used to treat BPH. The Cuban royal palm (Roystonea regia) is a member of this family and D-004, a lipid extract from its fruits, prevents prostate hyperplasia (PH) induced with testosterone, as opposed to dihydrotestosterone, in rodents. This study investigated whether D-004 could prevent the histological features of testosterone-induced PH in rats. Rats were distributed into six groups (10 rats per group): A negative control group receiving subcutaneous injections of soy oil and treated with vehicle, and five groups injected subcutaneously with testosterone and treated with the vehicle (positive control), D-004 (100, 200 and 400 mg/kg) or Saw palmetto (400 mg/kg). Treatments were given orally for 14 days. At sacrifice, prostates were removed and processed for light microscopy. The histopathological findings of PH were assessed according to a score-chart protocol. D-004 200 and 400 mg/kg, but not 100 mg/kg, significantly and moderately in a dose-dependent manner prevented prostate enlargement and the testosterone-induced histological changes. Compared with positive controls, D-004 200 and 400 mg/kg inhibited prostate size increases and the histological score up to 56.1% and 60.7%, respectively, while Saw palmetto 400 mg/kg reduced such variables by 45.8% and 49.0%, respectively. The effects of D-004 400 mg/kg on the histological changes, not on prostate size, were greater (p < 0.05) than those of Saw palmetto. D-004 and Saw palmetto did not affect body weight values. In conclusion, D-004 200 and 400 mg/kg administered orally for 14 days prevented the increase of prostate size and the testosterone-induced histological changes in rats, its effects being comparable or mildly better than those of Saw palmetto. These results extend previous data showing preventive effects of D-004 on testosterone-induced prostate enlargement with in rodents, and further studies are required to explore the mechanisms underlying such effects.


Assuntos
Arecaceae , Fitoterapia , Extratos Vegetais/administração & dosagem , Próstata/efeitos dos fármacos , Hiperplasia Prostática/patologia , Hiperplasia Prostática/prevenção & controle , Administração Oral , Animais , Relação Dose-Resposta a Droga , Intubação Gastrointestinal , Masculino , Fitoterapia/métodos , Extratos Vegetais/uso terapêutico , Próstata/citologia , Próstata/patologia , Hiperplasia Prostática/induzido quimicamente , Ratos , Ratos Sprague-Dawley , Testosterona/administração & dosagem
19.
Drugs Exp Clin Res ; 30(3): 117-23, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15366788

RESUMO

Osteoporosis is characterized by reduced bone mass, abnormal bone architecture and increased fracture risk. Ovariectomy impairs bone mass and metabolism in rats and ovariectomized rats are considered as a suitable model of postmenopausal osteoporosis. Mevalonate is required for producing lipoids that are important in osteoclast activity and thus drugs affecting mevalonate production can prevent bone loss in rodents. Policosanol is a cholesterol-lowering drug isolated from sugar cane wax that inhibits cholesterol biosynthesis through an indirect regulation of hydroxymethylglutaryl coenzyme A (HMG-CoA) reductase activity. The purpose of this study was to determine whether policosanol could prevent bone loss in the bones of ovariectomized rats by comparing its effects with those induced by estradiol. Sprague Dawley female rats were randomly distributed in four groups: a sham-operated group treated with Tween/H2O vehicle and three groups of ovariectomized rats treated with 17beta-estradiol (30 microg/kg/day) or policosanol (50 and 200 mg/kg/day), respectively, for 3 months. At treatment completion the rats were sacrificed, their bones removed and variables of bone resorption and formation were investigated by histomorphometry. Ovariectomy increased trabecular separation but diminished the number and thickness of trabecules. Estradiol and policosanol prevented these effects compared with ovariectomized controls. Both treatments also prevented an increase in the number of osteoclasts and their surface area induced by ovariectomy. Estradiol, but not policosanol, significantly prevented an increase of osteoblast surface area compared with ovariectomized controls. In conclusion, policosanol prevented bone loss and decreased bone resorption in ovariectomized rats, suggesting that it should be potentially useful in preventing bone loss in postmenopausal women.


Assuntos
Álcoois Graxos/farmacologia , Osteoporose/prevenção & controle , Ovariectomia , Administração Oral , Animais , Modelos Animais de Doenças , Esquema de Medicação , Avaliação Pré-Clínica de Medicamentos/métodos , Estradiol/administração & dosagem , Estradiol/farmacocinética , Álcoois Graxos/administração & dosagem , Álcoois Graxos/química , Feminino , Humanos , Injeções Subcutâneas , Intubação Gastrointestinal , Osteoclastos/efeitos dos fármacos , Osteoporose/tratamento farmacológico , Extratos Vegetais/administração & dosagem , Extratos Vegetais/química , Ratos , Ratos Sprague-Dawley
20.
Drugs Exp Clin Res ; 30(2): 75-88, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15272645

RESUMO

D-003 is a mixture of high molecular weight aliphatic primary acids purified from sugar cane wax (Saccharum officinarum, L) with cholesterol-lowering and antiplatelet effects. Previous studies, including a 6-month study conducted in rats, have shown no D-003-related toxicity. The present study was undertaken to investigate the effects of D-003 orally administered for 9 months in beagle dogs. The animals were randomly distributed in three groups: a control group receiving the vehicle only and two groups orally administered D-003 (200 and 400 mg/kg). Body weight gain, food consumption and clinical signs were controlled throughout the study. The effects of D-003 on collagen-induced platelet aggregation, bleeding time (BT) and coagulation parameters (prothrombin time and kaolin-activated thromboplastin time) were also investigated. Most blood biochemistry and hematological parameters were assessed at baseline and after 6 and 9 months of treatment, while total cholesterol (TC), triglycerides, platelet aggregation, BT and coagulation parameters were determined at baseline and after 9 months of treatment. At study completion, the animals were sacrificed. D-003 at a dose of 200 and 400 mg/kg significantly reduced TC (p < 0.05), significantly inhibited platelet aggregation and increased BT compared with levels in controls. Data analyses of body weight gain, food consumption, clinical observations, the remaining blood biochemistry and hematology indicators (including coagulation parameters, organ weight ratios and histopathological findings) showed no trends with D-003 doses or significant differences between control animals and treated groups. In conclusion, D-003 administered for 9 months to beagle dogs induced the expected effects with no evidence of drug-related toxicity.


Assuntos
Comportamento Animal/efeitos dos fármacos , Ácidos Graxos/toxicidade , Administração Oral , Animais , Colesterol/sangue , Cães , Relação Dose-Resposta a Droga , Ácidos Graxos/administração & dosagem , Feminino , Masculino , Nível de Efeito Adverso não Observado , Triglicerídeos/sangue
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