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Sepsis represents a complex clinical syndrome that results from a harmful host response to infection. The infections most associated with sepsis are pneumonia, intra-abdominal infection, and urinary tract infection. Tea tree oil (TTO) has shown high antibacterial activity; however, it exhibits low aqueous solubility and high volatility, which have motivated its nanoencapsulation. In this study, the performance of nanoemulsions (NE) and nanocapsules (NC) loaded with TTO was compared. These systems were prepared by spontaneous emulsification and nanoprecipitation methods, respectively. Poly-ε-caprolactone or Eudragit® RS100 were tested as polymers for NCs whereas Tween® 80 or Pluronic® F68 as surfactants in NE preparation. Pluronic® F68 and Eudragit® RS100 resulted in more homogeneous and stable nanoparticles. In accelerated stability studies at 4 and 25 °C, both colloidal suspensions (NC and NE) were kinetically stable. NCs showed to be more stable to photodegradation and less cytotoxic than NEs. After sepsis induction by the cecal ligation and puncture (CLP) model, both NE and NC reduced neutrophil infiltration into peritoneal lavage (PL) and kidneys. Moreover, the systems increased group thiols in the kidney and lung tissue and reduced bacterial growth in PL. Taken together, both systems showed to be effective against injury induced by sepsis; however, NCs should be prioritized due to advantages in terms of cytotoxicity and physicochemical stability.

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ETHNOPHARMACOLOGICAL RELEVANCE: Bauhinia forficata Link, is a Brazilian native plant and popularly known as pata-de-vaca ("paw-of-cow"). The tea prepared with their leaves has been extensively used in the Brazilian traditional practices for the diabetes treatment. The aim of the present study was to investigate the effect of capsules containing granules of a standardized extract of B. forficata leaves as adjuvant treatment on the glycemic control of patients with type-2 diabetes melitus. MATERIALS AND METHODS: A double-blind, randomized clinical trial using capsules containing granules prepared by wet granulation of a standardized extract from B. forficata leaves as adjuvant treatment, was conducted. 92 patients aged 18-75 years from an outpatient clinic with type-2 diabetes were randomly assigned by a simple randomization scheme, in a 1:1 ratio to receive capsules of B. forficata or placebo for four months. The capsules used contain 300 mg of standardized extract from B. forficata leaves, yielding 2% of total flavonoid content per capsule. Primary outcome was glycated hemoglobin levels and fasting plasma glucose at 4 months. Possible harms were also determined. RESULTS: The findings showed that at 4 months, the mean fasting plasma glucose levels and glycated hemoglobin were both significantly lower in the B. forficata group than in the placebo group. CONCLUSION: The present study suggests that the adjunctive use of capsules containing standardized extract of B. forficata can add to regular oral anti-diabetics in the metabolic and inflammatory control of type-2 diabetes patients.

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Ilex paraguariensis A. St. Hil. (Aquifoliaceae), popularly known as "yerba mate," has great economic and social significance for the population of Southern Latin America. This study was conducted (1) to investigate the phytochemical composition of four different standardized extracts, (2) to investigate its free radical scavenging properties, and (3) to investigate the anti-inflammatory action of I. paraguariensis and its major chemical markers. The chemical profile was achieved by Folin-Ciocalteu, by LC/DAD, and by LC/MS assays, while the antioxidant and anti-inflammatory properties were investigated, respectively, by DPPH assay and by inhibition of nitric oxide (Griess reaction) and TNF-α (ELISA). Our results demonstrated that the IA (aqueous infusion extract) showed higher amounts of total phenolic contents (266.62 ± 10.85 mg CAE·g-1 DE), the highest amounts of all six chemical markers (theobromine, 5-O-caffeoylquinic acid, 4-O-caffeoylquinic acid, 3-O-caffeoylquinic acid, caffeine, and rutin), and stronger antioxidant activity (EC50 = 54.4 ± 5.14 µg · mL-1). The IA extract also showed the lowest inhibition of NOx secretion (50.10 ± 8.97%) as well as inhibition of TNF-α (83.33 ± 4.01%). Regarding the chemical markers, all compounds showed strong inhibition of NOx secretion, especially theobromine, which was 200x more potent than dexamethasone. Furthermore, TNF-α secretion was also significantly decreased by THEO at 0.033 µM (22.15 ± 6.49%), NCA at 1.97 µM (27.46 ± 3.98%), CCA at 0.35 µM (39.76 ± 5.73%), CGA at 0.56 µM (23.58 ± 5.79%), CAF at 0.52 µM (26.45 ± 5.34%), and RUT at 0.16 µM (40.18 ± 3.70%). Our results suggest that I. paraguariensis and its major chemical markers have strong free radical scavenging properties as well as showed important anti-inflammatory activity and that these compounds in a plant extract may work based on several different mechanisms synergistically, resulting in moderating the immune system.

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In this study, the standardized dry extract of C. glaziovii (SDE) provided a significant vasorelaxant effect after contractions induced by phenylephrine in rat aortic rings in an endothelium-dependent manner, confirming that endothelial factors are needed to stimulate this response. A vasorelaxation close to that of acetylcholine was achieved, justifying the development of new formulations for this plant material. In this context, microparticles were selected to encapsulate SDE and the double emulsion technique was considered because of the hydrophilic nature of plant material. Two experimental designs were applied. Firstly, the effect of formulation parameters on particle size, size distribution and encapsulation efficiency (EE) was evaluated. As low EE was achieved, the effect of the osmotic pressure of the external phase was evaluated in a second experimental design. The presence of the osmotic agent (NaCl) impacted positively on the EE and slower in vitro release profile was obtained, which is desired in controlled release systems. The formation of denser and less porous particle surface, which was identified by SEM analysis, contributes to explain these findings. Microstructures showed to be a promising delivery system for the C. glaziovii SDE considering that a sustained release was achieved.

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Studies employing Cecropia glaziovii Snethl leaves have shown great potential in regard to their antiviral activity, mainly related to the phenolic compounds present in this species. The main goal of this work is to combine the therapeutic potential of this species with new technological strategies targeted at the development of an herbal nanoparticulate system for the preparation of a phytotherapeutic formulation. Poly (lactic-co-glycolic acid) nanoparticles containing the enriched flavonoid fraction of Cecropia glaziovii Snethl were developed through a study for the choice of preparation technique, amount of drug and surfactants used. These nanostructured systems were characterized by particle size, polydispersity, zeta potential, encapsulation efficiency and drug-loading capacity. A stability study of the formulations was conducted at room temperature over a period of 60 days. The optimal formulation that best fit the characteristics of the encapsulated material was determined. Sorbitan monooleate and the poloxamer 188 resulted in better colloidal stability, added to the organic and aqueous phases, respectively. These findings suggest that in the field of nanoparticles stability, it is important to evaluate the composition of the nanoparticulate system. This work highlights the importance of the optimization process, searching for a good formulation with suitable structural stabilization.

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There is increasing interest in natural antioxidants that are candidates for the prevention of brain damage occurring in major depressive disorders. Cecropia pachystachya is a tropical tree species of Central and South America and a rich source of polyphenols, particularly flavonoids. The aim of this study was to characterize the flavonoid profile of an enriched flavonoid fraction of C. pachystachya (EFF-Cp) and evaluate the antidepressant-like effects of its acute administration in behavior, cytokine levels, oxidative stress and energy metabolism parameters. The EFF-Cp chemical characterization was performed by HPLC/DAD and LC/QTOF. The antidepressant-like effects were performed by the forced swimming test, splash test and open field test. EFF-Cp revealed 15 flavonoids, including seven new glycosyl flavonoids for C. pachystachya. Quantitatively, EFF-Cp showed isoorientin (43.46 mg/g), orientin (23.42 mg/g) and isovitexin (17.45 mg/g) as major C-glycosyl flavonoids. In addition, EFF-Cp at doses 50 and 100 mg/kg reduced the immobility time in the forced swimming test, without changing the locomotor activity and grooming time. In addition, EFF-Cp was able to prevent the oxidative damage in some brain areas. In conclusion, the results of this study suggest that EFF-Cp exerts antidepressant-like effects with its antioxidant properties.

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ABSTRACTThe aim of this study is to investigate the effect of Cecropia glaziovii Snethl, Urticaceae, extracts on the oral glucose tolerance curve, on glycemia in alloxan-induced diabetic rats and vasorelaxant effect after the extraction process, and to standardize the extractive solutions. The effects of the process variables and their interactions were calculated in relation to dry residue, pH, total phenolic results and chemical marker content. Furthermore, the effect of the extracts (400 mg/kg), chlorogenic (2 or 15 mg/kg) and caffeic acids (2 mg/kg) were investigated on the oral glucose tolerance curve and on glycemia in alloxan-induced diabetic rats. Oral administration of ethanol extracts 4d20 and 8d20 significantly improved glucose tolerance in the hyperglycemic rats. Chlorogenic and caffeic acids, as well as the association of the compounds were able to significantly reduce glycemia after oral gavage treatments. On the other hand, the aqueous extracts did not alter the glycemia. The aqueous extracts (8020 and 9030) and only the higher dose of chlorogenic acid presented a significant effect on serum glucose lowering in diabetic rats. Additionally, the IC50 reveals that the ethanol extracts presented more potent vasodilator effects than the aqueous extracts in aortic rings. This study shows that C. glazioviistandardized extracts exhibits antihyperglycemic action, is able to improve glucose tolerance and has a potent vascular relaxing effect. These results are probably linked to concentrations of the main phenolic compounds of the extracts.

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Chronic stressful stimuli influence disease susceptibility to depression, cardiovascular, metabolic and neurodegenerative disorders. The present work investigated antidepressant and antioxidant properties of the aqueous extract from Cecropia pachystachya in a mouse model of chronic unpredictable stress (CUS). Our results indicated that acute administration of the aqueous extract (AE) from C. pachystachya (200 and 400mg/kg, p.o.) produced an antidepressant-like effect in the forced swimming test (FST). The chronic treatment with C. pachystachya extract (200mg/kg, p.o., for 14 days) prevented the depressant-like effect but not the anxiogenic effect induced by CUS. In addition to the behavioral modifications, the 14 days of CUS increased lipid peroxidation in the hippocampus (HP) and prefrontal cortex (PFC), decreased total thiol content and glutathione peroxidase activity in the HP. C. pachystachya AE administration during CUS protocol was able to prevent the oxidative damage induced by stress. However, no changes were observed in the activity of the antioxidant enzymes superoxide dismutase and catalase in the above cited brain areas after the stress protocol and treatment. Our results suggest that C. pachystachya prevented both depressive behavior and oxidative damage induced by CUS, supporting its neuroprotective potential against behavioral and biochemical dysfunctions induced by chronic stress.

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