RESUMO
OBJECTIVE: Oral candidiasis is a common fungal infection that affects the oral mucosa, and happens when Candida albicans interacts with bacteria in the oral microbiota, such as Streptococcus mutans, causing severe early childhood caries. C. albicans and S. mutans mixed biofilms are challenging to treat with conventional antimicrobial therapies, thus, new anti-infective drugs are required. This study aimed to test a drug delivery system based on chitosan microparticles loaded with geranium and lemongrass essential oils to inhibit C. albicans and S. mutans mixed biofilms. METHODOLOGY: Chitosan microparticles loaded with essential oils (CM-EOs) were obtained by spray-drying. Susceptibility of planktonic were performed according CLSI at 4 to 2,048 µg/mL. Mixed biofilms were incubated at 37ºC for 48 h and exposed to CM-EOs at 256 to 4,096 µg/mL. The antimicrobial effect was evaluated using the MTT assay, with biofilm architectural changes analyzed by scanning electron microscopy. RAW 264.7 cell was used to evaluate compound cytotoxicity. RESULTS: CM-EOs had better planktonic activity against C. albicans than S. mutans. All samples reduced the metabolic activity of mixed C. albicans and S. mutans biofilms, with encapsulated oils showing better activity than raw chitosan or oils. The microparticles reduced the biofilm on the slides. The essential oils showed cytotoxic effects against RAW 264.7 cells, but encapsulation into chitosan microparticles decreased their toxicity. CONCLUSION: This study demonstrates that chitosan loaded with essential oils may provide an alternative method for treating diseases caused by C. albicans and S. mutans mixed biofilm, such as dental caries.
Assuntos
Quitosana , Cárie Dentária , Óleos Voláteis , Pré-Escolar , Humanos , Óleos Voláteis/farmacologia , Candida albicans , Streptococcus mutans , Quitosana/farmacologia , Cárie Dentária/prevenção & controle , BiofilmesRESUMO
Abstract Oral candidiasis is a common fungal infection that affects the oral mucosa, and happens when Candida albicans interacts with bacteria in the oral microbiota, such as Streptococcus mutans, causing severe early childhood caries. C. albicans and S. mutans mixed biofilms are challenging to treat with conventional antimicrobial therapies, thus, new anti-infective drugs are required. Objective This study aimed to test a drug delivery system based on chitosan microparticles loaded with geranium and lemongrass essential oils to inhibit C. albicans and S. mutans mixed biofilms. Methodology Chitosan microparticles loaded with essential oils (CM-EOs) were obtained by spray-drying. Susceptibility of planktonic were performed according CLSI at 4 to 2,048 µg/mL. Mixed biofilms were incubated at 37ºC for 48 h and exposed to CM-EOs at 256 to 4,096 µg/mL. The antimicrobial effect was evaluated using the MTT assay, with biofilm architectural changes analyzed by scanning electron microscopy. RAW 264.7 cell was used to evaluate compound cytotoxicity. Results CM-EOs had better planktonic activity against C. albicans than S. mutans. All samples reduced the metabolic activity of mixed C. albicans and S. mutans biofilms, with encapsulated oils showing better activity than raw chitosan or oils. The microparticles reduced the biofilm on the slides. The essential oils showed cytotoxic effects against RAW 264.7 cells, but encapsulation into chitosan microparticles decreased their toxicity. Conclusion This study demonstrates that chitosan loaded with essential oils may provide an alternative method for treating diseases caused by C. albicans and S. mutans mixed biofilm, such as dental caries.
RESUMO
Dietary fiber intake plays an important role in the prevention of obesity. This study aimed at investigating the effect of cashew fiber without low molecular weight compounds (CABwc) on obesity prevention and metabolomics in a murine model of diet-induced obesity. Mice were fed a chow diet (CD), a high-fat diet (HFD) or a high-fat diet supplemented with CABwc (10%) (HFD-CABwc) for 15 weeks. The body weight, abdominal fat, serum glucose levels, insulin and lipid profiles, satiety hormones such as leptin and ghrelin, digestive enzymes such as amylase and lipase, and inflammatory mediators such as TNF-α, IL-6, and adiponectin were measured, in addition to performing serum and hepatic tissue analyses. The metabolomic analysis was based on nuclear magnetic resonance (NMR) spectroscopy of serum and feces. The effects observed with ingestion of CABwc were appetite control and prevention of hyperglycemia, hyperinsulinemia and hypertriglyceridemia, as well as the prevention of the inflammatory process and reduction of liver injury caused by the HFD. In addition, NMR evidenced the presence of SCFAs in serum and feces of mice fed with HFD-CABwc. These findings suggest that CABwc promoted satiety in mice, improving the metabolism of glucose and lipids. Positive effects of obesity prevention may be associated with SCFA production.
Assuntos
Anacardium/química , Dieta Hiperlipídica/efeitos adversos , Fibras na Dieta/farmacologia , Obesidade/induzido quimicamente , Obesidade/prevenção & controle , Animais , Fibras na Dieta/análise , Suplementos Nutricionais , Fezes/química , Espectroscopia de Ressonância Magnética , Metabolômica , Camundongos , Obesidade/sangueRESUMO
To characterize the protective effects of the triterpenoid mixture alpha, beta-amyrin (AMY, 20 mg/kg, during 15 days) on the reactivity of isolated aorta of high-fat diet (HFD)-induced obese mice. Male Swiss mice were fed with HFD or normal diet (ND) for 15 weeks. Contractions of thoracic aorta in response to KCl or phenylephrine (PHE) and relaxation by acetylcholine (ACh) or sodium nitroprusside (SNP) were analyzed. HFD-fed mice developed hyperglycemia, hyperlipidemia, and significant body weight gain, parameters prevented by AMY treatment. Whereas aortic contractility did not differ in response to KCl, contractions induced by PHE (1 µM) as well as relaxation induced by ACh (1-30 µM) or SNP (1 nM-0.1 mM) on PHE-contracted aorta were decreased (p < 0.05) in tissues of HFD compared to ND mice, phenomenon significantly (p < 0.05) diminished in HFD mice treated with AMY. The relaxant actions of ACh and SNP were inhibited (p < 0.05) by tetraethylammonium (TEA, 5 mM), apamin (0.1 µM), and 4-aminopyridine (4-AP; 3 mM) in aortae from ND group, but not from HFD. Treatment of HFD mice with AMY rescued the inhibitory effect of TEA (p < 0.05) on vasorelaxant actions of ACh and SNP. 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (ODQ) inhibited similarly the relaxant effects of SNP in all groups. 8-Br-cGMP relaxed with similar profile aortae of all groups. By preventing HFD-induced obesity in mice, AMY rescued the blunted contractile response to PHE, and the attenuated vasorelaxation and K+ channel activation (opening) induced by ACh and SNP in isolated aorta.
Assuntos
Aorta Torácica/efeitos dos fármacos , Dieta Hiperlipídica/efeitos adversos , Obesidade/tratamento farmacológico , Ácido Oleanólico/análogos & derivados , Vasoconstrição/efeitos dos fármacos , Vasodilatação/efeitos dos fármacos , Animais , Aorta Torácica/fisiologia , Peso Corporal/efeitos dos fármacos , Peso Corporal/fisiologia , Relação Dose-Resposta a Droga , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/fisiologia , Masculino , Camundongos , Obesidade/etiologia , Obesidade/fisiopatologia , Ácido Oleanólico/farmacologia , Ácido Oleanólico/uso terapêutico , Triterpenos/farmacologia , Triterpenos/uso terapêutico , Vasoconstrição/fisiologia , Vasodilatação/fisiologiaRESUMO
Obesity remains a global problem. In search of phytochemicals that have antiobesity potential, this study evaluated α,ß-amyrin, a triterpenoid mixture from Protium heptaphyllum, on high-fat diet-induced obesity in mice. Groups of mice (n = 8) were fed a normal diet or a high-fat diet, and were orally treated or not treated with either α,ß-amyrin (10 or 20 mg/kg) or sibutramine (10 mg/kg) for 15 weeks. Variables measured at termination were body weight, visceral fat accumulation, adipocyte surface area, peroxisome proliferator-activated receptor gamma, and lipoprotein lipase expressions in adipose tissue, the levels of plasma glucose and insulin, the satiety hormones ghrelin and leptin, the digestive enzymes amylase and lipase, and the inflammatory mediators TNF-α, interleukin-6, and MCP-1. Results showed that α,ß-amyrin treatment resulted in lower high-fat diet-induced increases in body weight, visceral fat content, adipocyte surface area, peroxisome proliferator-activated receptor gamma, and lipoprotein lipase expressions, and blood glucose and insulin levels. Additionally, the markedly elevated leptin and decreased ghrelin levels seen in the high-fat diet-fed control mice were significantly modulated by α,ß-amyrin treatment. Furthermore, α,ß-amyrin decreased serum TNF-α and MCP-1. These results suggest that α,ß-amyrin could be beneficial in reducing high-fat diet-induced obesity and associated disorders via modulation of enzymatic, hormonal, and inflammatory responses.
Assuntos
Fármacos Antiobesidade/farmacologia , Obesidade/tratamento farmacológico , Ácido Oleanólico/análogos & derivados , Gordura Abdominal/efeitos dos fármacos , Adipócitos/citologia , Adipócitos/efeitos dos fármacos , Tecido Adiposo/efeitos dos fármacos , Tecido Adiposo/metabolismo , Tecido Adiposo Branco/efeitos dos fármacos , Animais , Glicemia/metabolismo , Peso Corporal/efeitos dos fármacos , Burseraceae/química , Ciclobutanos/farmacologia , Dieta Hiperlipídica , Grelina/sangue , Insulina/sangue , Leptina/sangue , Lipídeos/sangue , Lipase Lipoproteica/metabolismo , Masculino , Camundongos , Obesidade/sangue , Obesidade/etiologia , Ácido Oleanólico/química , Ácido Oleanólico/isolamento & purificação , Ácido Oleanólico/farmacologia , PPAR gama/metabolismo , Fitoterapia , Resistina/sangueRESUMO
OBJECTIVES: (-)-Myrtenol is a natural fragrance monoterpenoid structurally related to α-pinene found in diverse plant essential oils. This study was aimed to assess the anti-ulcerogenic potential of (-)-myrtenol against ethanol-induced gastric lesions and to elucidate the underlying mechanism(s). METHODS: Gastroprotective activity of (-)-myrtenol was evaluated using the mouse model of ethanol-induced gastric damage. To elucidate the gastroprotective mechanism(s), the roles of GABA, prostaglandins, nitric oxide and KATP channels were assessed. Besides, the oxidative stress-related parameters and the mucus content in gastric tissues were analysed. KEY FINDINGS: (-)-Myrtenol at oral doses of 25, 50 and 100 mg/kg significantly decreased the severity of ethanol-induced gastric lesions affording gastroprotection that was accompanied by a decrease in the activity of myeloperoxidase and malondialdehyde, an increase in GPx, SOD, and catalase activity in gastric tissues, and with well-maintained normal levels of nitrite/nitrate, gastric mucus and NP-SHs. Pretreatment with GABA-A receptor antagonist flumazenil, the COX inhibitor indomethacin, and NO synthesis inhibitor L-NAME but not with KATP channel blocker glibenclamide significantly blocked the (-)-myrtenol gastroprotection. CONCLUSION: These results provide first-time evidence for the gastroprotective effect of (-)-myrtenol that could be related to GABAA -receptor activation and antioxidant activity.