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1.
Animals (Basel) ; 13(14)2023 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-37508104

RESUMO

Toxoplasma gondii and Neospora caninum are obligate intracellular protozoan parasites infecting a wide range of hosts worldwide. However, information on the epidemiology of toxoplasmosis and neosporosis in cats from Portugal is limited. Thus, this study aims to evaluate anti-T. gondii and anti-N. caninum seroprevalence in client-owned cats from Portugal and to identify risk factors using a panel of well-characterized sera. A total of 183 domestic cats were sampled and screened for antibodies against T. gondii and N. caninum using commercial ELISA assays, and their owners answered an online questionnaire designed to obtain background information. The overall anti-T. gondii and anti-N. caninum seroprevalences were 13.1% (CI: 8.97-18.77) and 3.8% (CI: 1.87-7.68), respectively. Univariate analysis revealed that living strictly indoors was a significant protection factor (cOR: 0.053; CI: 0.005-0.627), and the presence of a chronic disease a significant risk factor (cOR: 3.106; CI: 1.062-9.082) to T. gondii seroprevalence. When performing multivariate analysis, only chronic disease (aOR: 57.527; CI: 1.7-1976.7) and seropositivity to N. caninum (aOR: 7.929; CI:0.8-82.9) were found to be a significant risk factor to anti-T. gondii antibodies. To the best of our knowledge, this is the first report of N. caninum seropositivity in cats from Portugal.

2.
Food Chem Toxicol ; 174: 113689, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36858299

RESUMO

Punica granatum L. (pomegranate) has been used in functional foods due to its various health benefits. However, the in vivo biological potential of its leaf remains little known. This study has aimed to characterize the antineoplastic and toxicological properties of using pomegranate leaf infusion (PLI) on transgenic mice carrying human papillomavirus (HPV) type 16 oncogenes. Thirty-eight mice were divided into 3 wild-type (WT) and 3 transgenic (HPV) groups, with exposure to 0.5% PLI, 1.0% PLI, and water. The animals' body weight, drink and food consumption were recorded. Internal organs, skin samples and intracardiac blood were collected to evaluate toxicological parameters, neoplastic lesions and oxidative stress. The results indicated that PLI was safe as no mortality, no behavioural disorders and no significant differences in the levels of microhematocrit, serum biochemical markers, internal organ histology, and oxidative stress was found among the WT groups. Histological analysis revealed that HPV animals that consumed PLI exhibited reduced hepatic, renal and cutaneous lesions compared with the HPV control group. Low-dose PLI consumption significantly diminished renal hydronephrosis lesions and relieved dysplasia and carcinoma lesions in the chest skin. Oxidative stress analysis showed that low-dose PLI consumption may have more benefits than high-dose PLI. These results suggest that oral administration of PLI has the potential to alleviate non-neoplastic and neoplastic lesions against HPV16-induced organ and skin injuries, though this requires further scientific research studies.


Assuntos
Antineoplásicos , Infecções por Papillomavirus , Punica granatum , Camundongos , Animais , Humanos , Camundongos Transgênicos , Papillomavirus Humano 16 , Infecções por Papillomavirus/patologia , Folhas de Planta
3.
Biomedicines ; 10(10)2022 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-36289857

RESUMO

Essential oils are natural compounds used by humans for scientific purposes due to their wide range of properties. Eugenol is mostly present in clove oil, while pulegone is the main constituent of pennyroyal oil. To guarantee the safe use of eugenol and pulegone for both humans and animals, this study addressed, for the first time, the effects of these compounds, at low doses (chronic toxicity) and high doses (acute toxicity), in laboratory animals. Thirty-five FVB/n female mice were randomly assigned to seven groups (n = 5): group I (control, non-additive diet); group II (2.6 mg of eugenol + 2.6 mg of pulegone); group III (5.2 mg of eugenol + 5.2 mg of pulegone); group IV (7.8 mg of eugenol + 7.8 mg of pulegone); group V (7.8 mg of eugenol); group VI (7.8 mg of pulegone); and group VII (1000 mg of eugenol + 1000 mg of pulegone). The compounds were administered in the food. Groups I to VI were integrated into the chronic toxicity study, lasting 28 days, and group VII was used in the acute toxicity study, lasting 7 days. Animals were monitored to assess their general welfare. Water and food intake, as well as body weight, were recorded. On the 29th day, all animals were euthanized by an overdose of ketamine and xylazine, and a complete necropsy was performed. Blood samples were collected directly from the heart for microhematocrit and serum analysis, as well as for comet assay. Organs were collected, weighed, and fixed in formaldehyde for further histological analysis and enzymatic assay. Eugenol and pulegone induced behavioral changes in the animals, namely in the posture, hair appearance and grooming, and in mental status. These compounds also caused a decrease in the animals' body weight, as well as in the food and water consumption. A mortality rate of 20% was registered in the acute toxicity group. Both compounds modulated the serum levels of triglycerides and alanine aminotransferase. Eugenol and pulegone induced genetic damage in all animals. Eugenol increased the activity of the CAT enzyme. Both compounds increased the GR enzyme at the highest dose. Moreover, pulegone administered as a single compound increased the activity of the GST enzyme. Histopathological analysis revealed inflammatory infiltrates in the lungs of groups II, III, and IV. The results suggest that eugenol and pulegone may exert beneficial or harmful effects, depending on the dose, and if applied alone or in combination.

4.
J Am Assoc Lab Anim Sci ; 61(1): 89-95, 2022 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-34847984

RESUMO

Precise oral dosing in rodents is usually achieved by intragastric gavage. If performed incorrectly due to technical difficulties, inexperience, or animal resistance, oral gavage may have animal welfare implications such as esophageal and gastric rupture and aspiration. The stress that is induced by this procedure can also lead to confounding results. In several animal models, drug vehicles must be sugar-free, deliver drugs in a specific formulation, and sometimes supply water. Gelatin has all of these properties. The current study aimed to evaluate the use of gelatin vehicles with different sensory features as an alternative to oral gavage. We investigated the time taken by 2 different inbred mouse strains, FVB/N and C57BL/6J, to ingest sugar-free gelatin pellets of varying flavors. Results showed that FVB/N mice took more time to eat the unflavored, strawberry and diet-flavored gelatin pellets than did C57BL/6J mice. Both strains showed low preference for lemon flavor, with the same ingestion times after the second day. This study showed that the C57BL/6J mice are more likely to eat gelatin than are FVB/N mice, and that the 2 strains of mice show a lower preference for lemon flavoring as compared with other flavors. This method of voluntarily oral administration offers an alternative to gavage for studies that use oral dosing studies.


Assuntos
Aromatizantes , Alimentos , Gelatina , Administração Oral , Animais , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos
5.
Nutrients ; 13(12)2021 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-34960081

RESUMO

The role of dietary profiles in promoting or reducing the risk of multiple types of cancer is increasingly clear, driving the search for balanced foods and nutraceuticals. The red seaweed Grateloupia turuturu has been used as human food showing a balanced nutritional profile. This study aims to test in vivo chemopreventive effects of G. turuturu against cutaneous pre-malignant lesions in transgenic mice for the human papillomavirus type 16 (HPV16). Forty-four female HPV+/- or HPV-/- mice received a standard diet or were supplemented with 10% G. turuturu for 22 consecutive days. Cutaneous lesions (ear and chest skin) were identified histologically. Complementarily, the weights and histology of internal organs as well as blood biochemical and DNA integrity parameters were also assessed. G. turuturu consistently reduced the incidence of epidermal dysplasia induced by HPV16 on both cutaneous sites. Moreover, biochemical, DNA integrity and histological analyses confirmed G. turuturu edibility as no signs of toxicity were found. Dietary supplementation with G. turuturu is an effective and safe chemopreventive strategy in this model.


Assuntos
Papillomavirus Humano 16/genética , Infecções por Papillomavirus/virologia , Fitoterapia , Rodófitas , Alga Marinha , Animais , Anticarcinógenos , Produtos Biológicos , Suplementos Nutricionais , Feminino , Camundongos , Camundongos Transgênicos , Neoplasias Cutâneas
6.
Food Funct ; 12(9): 4005-4014, 2021 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-33978005

RESUMO

Tilia platyphyllos Scop. is a popular broad-leaved tree, native to Central and Southern Europe. Hydroethanolic extracts rich in phenolic compounds obtained from T. platyphyllos Scop. have shown in vitro antioxidant, anti-inflammatory and antitumor properties. The aim of this work was to evaluate the therapeutic properties of a hydroethanolic extract obtained from T. platyphyllos in HPV16-transgenic mice. The animals were divided into eight groups according to their sex and phenotype. Four groups of female: HPV+ exposed to linden (HPV linden; n = 6), HPV+ (HPV water; n = 4), HPV- exposed to linden (WT linden; n = 5) and HPV- (WT water; n = 4) and four groups of male: HPV+ exposed to linden (HPV linden; n = 5), HPV+ (HPV water; n = 5), HPV- exposed to linden (WT linden; n = 5) and HPV- (WT water; n = 7). The linden (Tilia platyphyllos Scop.) extract was orally administered at a dose of 4.5 mg/10 mL per animal (dissolved in water) and changed daily for 33 days. The hydroethanolic extract of T. platyphyllos consisted of protocatechuic acid and (-)-epicatechin as the most abundant phenolic acid and flavonoid, respectively, and was found to be stable during the studied period. In two male groups a significant positive weight gain was observed but without association with the linden extract. Histological, biochemical, and oxidative stress analyses for the evaluation of kidney and liver damage support the hypothesis that the linden extract is safe and well-tolerated under the present experimental conditions. Skin histopathology does not demonstrate the chemopreventive effect of the linden extract against HPV16-induced lesions. The linden extract has revealed a favourable toxicological profile; however, additional studies are required to determine the chemopreventive potential of the linden extract.


Assuntos
Antineoplásicos/farmacologia , Epiderme/patologia , Papillomavirus Humano 16 , Infecções por Papillomavirus/patologia , Extratos Vegetais/farmacologia , Tilia , Animais , Antineoplásicos/toxicidade , Catequina/análise , Feminino , Flavonoides/análise , Hidroxibenzoatos/análise , Rim/efeitos dos fármacos , Rim/patologia , Fígado/efeitos dos fármacos , Fígado/patologia , Masculino , Camundongos , Camundongos Transgênicos , Extratos Vegetais/química , Extratos Vegetais/toxicidade
7.
In Vivo ; 34(4): 1797-1803, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32606149

RESUMO

AIM: This work intended to improve the knowledge of the rat model of prostate cancer (PCa) by ultrasonographic monitoring. MATERIALS AND METHODS: Male Wistar rats were divided into control (n=8) and PCa (n=14) groups. PCa development was induced in the PCa group through the sequential administration of the anti-androgenic drug flutamide, testosterone propionate and the carcinogenic N-methyl-N-nitrosourea. The prostate was evaluated by ultrasonography at five timepoints along 49 weeks of the experimental protocol. Ventral prostate lobes were observed in all ultrasonographic examinations. RESULTS: The ventral prostate area of the control group increased gradually between the first and the last ultrasonographic examination. The ventral prostate area of PCa groups decreased due to flutamide administration and increased after androgen and carcinogen administration. The area of the dorsal prostate lobe increased between the fourth and the fifth ultrasonographic examination. In the last ultrasonographic examination, hypoechoic and anechoic lesions were observed in the PCa group. CONCLUSION: To our knowledge, this is the first study presenting a follow-up of rat prostatic dimensions by ultrasonography. Ultrasonography is a feasible approach for prostate cancer monitoring in experimental models.


Assuntos
Neoplasias da Próstata , Testosterona , Animais , Seguimentos , Humanos , Masculino , Neoplasias da Próstata/diagnóstico por imagem , Ratos , Ratos Wistar
8.
Mar Drugs ; 17(11)2019 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-31671845

RESUMO

Some diet profiles are associated with the risk of developing cancer; however, some nutrients show protective effects. Porphyra umbilicalis is widely consumed, having a balanced nutritional profile; however, its potential for cancer chemoprevention still needs comprehensive studies. In this study, we incorporated P. umbilicalis into the diet of mice transgenic for the human papillomavirus type 16 (HPV16), which spontaneously develop pre-malignant and malignant lesions, and determined whether this seaweed was able to block lesion development. Forty-four 20-week-old HPV+/- and HPV-/- mice were fed either a base diet or a diet supplemented with 10% seaweed. At the end of the study, skin samples were examined to classify HPV16-induced lesions. The liver was also screened for potential toxic effects of the seaweed. Blood was used to study toxicological parameters and to perform comet and micronucleus genotoxicity tests. P. umbilicalis significantly reduced the incidence of pre-malignant dysplastic lesions, completely abrogating them in the chest skin. These results suggest that P. umbilicalis dietary supplementation has the potential to block the development of pre-malignant skin lesions and indicate its antigenotoxic activity against HPV-induced DNA damage. Further studies are needed to establish the seaweed as a functional food and clarify the mechanisms whereby this seaweed blocks multistep carcinogenesis induced by HPV.


Assuntos
Porphyra , Neoplasias Cutâneas/dietoterapia , Neoplasias Cutâneas/patologia , Animais , Dano ao DNA , Dieta , Dietoterapia , Suplementos Nutricionais , Papillomavirus Humano 16 , Humanos , Hiperplasia/patologia , Camundongos , Camundongos Transgênicos , Alga Marinha , Pele/patologia , Neoplasias Cutâneas/virologia
9.
Diagnostics (Basel) ; 9(3)2019 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-31262045

RESUMO

The rat has been frequently used as a model to study several human diseases, including cancer. In many research protocols using cancer models, researchers find it difficult to perform several of the most commonly used techniques and to compare their results. Although the protocols for the study of carcinogenesis are based on the macroscopic and microscopic anatomy of organs, few studies focus on the use of imaging. The use of imaging modalities to monitor the development of cancer avoids the need for intermediate sacrifice to assess the status of induced lesions, thus reducing the number of animals used in experiments. Our work intends to provide a complete and systematic overview of rat prostate anatomy and imaging, facilitating the monitoring of prostate cancer development through different imaging modalities, such as ultrasonography, computed tomography (CT) and magnetic resonance imaging (MRI).

10.
J Sci Food Agric ; 98(8): 2837-2844, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29363750

RESUMO

Obesity is linked to the onset of many diseases such as diabetes mellitus, cardiovascular diseases and cancer, among others. The prevalence of obesity nearly doubled worldwide between 1980 and 2014. Simultaneously, in the last decade, the effects of sulforaphane as a potential treatment for obesity have been investigated, with promising results. Fruits and vegetables and their processed agri-food co-products are good sources of natural health-promoting compounds. Brassica crops are among the most produced crops in the world and are a good source of glucoraphanin, which, following hydrolysis, releases sulforaphane. The Brassicaceae family generates large amounts of co-products with no intended use, causing negative economic and environmental impact. Valorization of these co-products could be achieved through their exploitation for the extraction of bioactive compounds such as sulforaphane. However, the extraction process still needs further improvement for its economic feasibility. This article reviews the potential effects of sulforaphane in the treatment of obesity, linked to the relevance of giving Brassica co-products added value, which is of key importance for the competitiveness of farmers and the agri-food industry. © 2018 Society of Chemical Industry.


Assuntos
Fármacos Antiobesidade/administração & dosagem , Brassica/química , Isotiocianatos/administração & dosagem , Obesidade/tratamento farmacológico , Extratos Vegetais/administração & dosagem , Animais , Fármacos Antiobesidade/isolamento & purificação , Humanos , Isotiocianatos/isolamento & purificação , Obesidade/metabolismo , Extratos Vegetais/isolamento & purificação , Sulfóxidos
11.
J Ultrasound Med ; 36(12): 2459-2466, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28646597

RESUMO

OBJECTIVES: This study aimed to evaluate the impact of long-term exercise training on the vascularization of rat mammary tumors. METHODS: Female rats were divided into 4 groups: N-methyl-N-nitrosourea (MNU) treated sedentary, MNU treated exercised, control sedentary, and control exercised. Tumor development was induced in the MNU groups by MNU administration. Exercised groups were trained for 35 weeks. Tumor vascularization was evaluated by pulsed Doppler and contrast-enhanced ultrasonography. RESULTS: The pulsatility and resistive indices were slightly higher in the MNU sedentary group (P > .05). Mammary tumors mainly had centripetal and heterogeneous enhancement of the contrast, clear margins, and the presence of penetrating vessels. The MNU exercised group had a lower arrival time and time to peak and higher peak intensity, wash-in, and wash-out (P > .05). The area under the curve was similar between groups (P > .05). CONCLUSIONS: The contrast-enhanced ultrasonographic study did not detect differences in mammary tumor vascularization between MNU sedentary and MNU exercised groups previously detected by power Doppler imaging, B-flow imaging, and immunohistochemistry.


Assuntos
Meios de Contraste , Aumento da Imagem/métodos , Neoplasias Mamárias Animais/irrigação sanguínea , Condicionamento Físico Animal , Ultrassonografia/métodos , Animais , Modelos Animais de Doenças , Feminino , Neoplasias Mamárias Animais/diagnóstico por imagem , Neoplasias Mamárias Animais/patologia , Neovascularização Patológica/diagnóstico por imagem , Ratos , Ratos Sprague-Dawley , Tempo
12.
Life Sci ; 176: 35-41, 2017 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-28336398

RESUMO

AIMS: The inhibition of mast cells' degranulation may be an approach to prevent the formation of new vessels during the mammary carcinogenesis. MATERIALS AND METHODS: Female Sprague-Dawley rats were randomly divided into five experimental groups. Mammary tumors were induced by intraperitoneal injection of N-methyl-N-nitrosourea (MNU). Animals from group II were treated with ketotifen for 18weeks immediately after the MNU administration, while animals from group III only received the ketotifen after the development of the first mammary tumor. Mammary tumors vascularization was assessed by ultrasonography (Doppler, B Flow and contrast-enhanced ultrasound) and immunohistochemistry (vascular endothelial growth factor-A). KEY FINDINGS AND SIGNIFICANCE: Similar to what occurs in women with breast cancer, the majority of MNU-induced mammary tumors exhibited a centripetal enhancement order of the contrast agent, clear margin and heterogeneous enhancement. Ultrasonographic and immunohistochemical data suggest that the inhibition of mast cells' degranulation did not change the mammary tumors vascularization.


Assuntos
Neoplasias Mamárias Animais , Mastócitos/metabolismo , Metilnitrosoureia/toxicidade , Neovascularização Patológica , Ultrassonografia , Animais , Feminino , Cetotifeno/farmacologia , Neoplasias Mamárias Animais/irrigação sanguínea , Neoplasias Mamárias Animais/induzido quimicamente , Neoplasias Mamárias Animais/diagnóstico por imagem , Neoplasias Mamárias Animais/metabolismo , Neovascularização Patológica/diagnóstico por imagem , Neovascularização Patológica/metabolismo , Neovascularização Patológica/patologia , Ratos , Ratos Sprague-Dawley
13.
J Hypertens ; 25(12): 2486-96, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17984671

RESUMO

OBJECTIVES: D/L-Nebivolol is a lypophilic beta1-adrenergic antagonist which is devoid of intrinsic sympathomimetic activity and can increase nitric oxide (NO) bioavailability with its subsequent vasodilating properties. The purpose of the present work was to assess the effect of long-term nebivolol administration on both renal damage and endothelial dysfunction induced by renal mass reduction (RMR) in rats. Atenolol, which does not increase NO bioavailability, was included in the study as a comparative beta-adrenoceptor antagonist. METHODS: Rats were subjected to both right nephrectomy and surgical removal of two-thirds of the left kidney in order to retain approximately one-sixth of the total renal mass. One week after ablation, rats were distributed randomly according to the following experimental groups: control group containing RMR rats without treatment; RMR rats treated daily with nebivolol for 6 months (drinking water, 8 mg/kg per day); and RMR rats treated daily with atenolol for 6 months (drinking water, 80 mg/kg per day). A group of sham-operated animals was also included. RESULTS: Administration of either nebivolol or atenolol similarly reduced arterial pressure in comparison with RMR untreated animals; however, animals receiving nebivolol presented lower levels of collagen type I expression as well as lower glomerular and interstitial fibrosis than those receiving atenolol. Urinary excretion of oxidative stress markers were also lower in animals receiving nebivolol than in rats treated with atenolol. Furthermore, nebivolol prevented RMR-induced endothelial dysfunction more efficiently than atenolol. CONCLUSIONS: Nebivolol protects against renal fibrosis, oxidative stress and endothelial dysfunction better than equivalent doses, in terms of arterial pressure reduction, of atenolol in a hypertensive model of renal damage induced by RMR.


Assuntos
Antagonistas Adrenérgicos beta/administração & dosagem , Benzopiranos/administração & dosagem , Etanolaminas/administração & dosagem , Hipertensão Renal/tratamento farmacológico , Animais , Dinoprosta/análogos & derivados , Dinoprosta/metabolismo , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/fisiopatologia , Fibrose , Hipertensão Renal/patologia , Hipertensão Renal/fisiopatologia , Rim/efeitos dos fármacos , Rim/patologia , Rim/fisiopatologia , Masculino , Nebivolol , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Wistar , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo
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