Himatanthus drasticus (Apocynaceae), a laticifer plant, is popularly known as janaguba. This late... more Himatanthus drasticus (Apocynaceae), a laticifer plant, is popularly known as janaguba. This latex has been widely used in traditional folk medicine to treat diseases such cancer and ulcer. This st...
Contact dermatitis produces an inflammatory reaction primarily via stimulation of keratinocytes a... more Contact dermatitis produces an inflammatory reaction primarily via stimulation of keratinocytes and cells of the immune system, which promote the release of cytokines, reactive oxygen species (ROS), and other chemical mediators. Eugenol (EUG, phenylpropanoid of essential oils) has attracted attention due to its anti-inflammatory properties, as well as antioxidant effect. On the other hand, it is volatile and insoluble and is a skin irritant. In this case, nanostructured systems have been successfully employed as a drug carrier for skin diseases since they improve both biological and pharmaceutical properties of active compounds. The cytotoxic, antioxidant, and anti-inflammatory effects of EUG were assessed in human neutrophils and keratinocytes. Additionally, polymeric nanocarries (NCEUG) were prepared to improve the chemical and irritant characteristics of EUG. EUG presented apparent safety and antioxidant and anti-inflammatory effects on human neutrophils, but presented cytotoxic ...
Naunyn-Schmiedeberg's Archives of Pharmacology, 2016
In a previous study, we performed the chemical characterization of a polyvinyl alcohol (PVA) memb... more In a previous study, we performed the chemical characterization of a polyvinyl alcohol (PVA) membrane supplemented with latex proteins (LP) displaying wound healing activity, and its efficacy as a delivery system was demonstrated. Here, we report on aspects of the mechanism underlying the performance of the PVA-latex protein biomembrane on wound healing. LP-PVA, but not PVA, induced more intense leukocyte (neutrophil) migration and mast cell degranulation during the inflammatory phase of the cicatricial process. Likewise, LP-PVA induced an increase in key markers and mediators of the inflammatory response (myeloperoxidase activity, nitric oxide, TNF, and IL-1β). These results demonstrated that LP-PVA significantly accelerates the early phase of the inflammatory process by upregulating cytokine release. This remarkable effect improves the subsequent phases of the healing process. The polyvinyl alcohol membrane was fully absorbed as an inert support while LP was shown to be active. It is therefore concluded that the LP-PVA is a suitable bioresource for biomedical engineering.
Evidence-Based Complementary and Alternative Medicine, 2015
Plumeria rubra(Apocynaceae) is frequently used in folk medicine for the treatment of gastrointest... more Plumeria rubra(Apocynaceae) is frequently used in folk medicine for the treatment of gastrointestinal disorders, hepatitis, and tracheitis, among other infirmities. The aim of this study was to investigate the gastroprotective potential of a protein fraction isolated from the latex ofPlumeria rubra(PrLP) against ethanol-induced gastric lesions and describe the underlying mechanisms. In a dose-dependent manner, the pretreatment with PrLP prevented ethanol-induced gastric lesions in mice after single intravenous administration. The gastroprotective mechanism of PrLP was associated with the involvement of prostaglandins and balance of oxidant/antioxidant factors. Secondarily, the NO/cGMP/KATPpathway and activation of capsaicin-sensitive primary afferents were also demonstrated as part of the mechanism. This study shows that proteins extracted from the latex ofP.rubraprevent gastric lesions induced in experimental animals. Also, the results support the use of the plant in folk medicine.
Himatanthus drasticus (Apocynaceae), a laticifer plant, is popularly known as janaguba. This late... more Himatanthus drasticus (Apocynaceae), a laticifer plant, is popularly known as janaguba. This latex has been widely used in traditional folk medicine to treat diseases such cancer and ulcer. This st...
Contact dermatitis produces an inflammatory reaction primarily via stimulation of keratinocytes a... more Contact dermatitis produces an inflammatory reaction primarily via stimulation of keratinocytes and cells of the immune system, which promote the release of cytokines, reactive oxygen species (ROS), and other chemical mediators. Eugenol (EUG, phenylpropanoid of essential oils) has attracted attention due to its anti-inflammatory properties, as well as antioxidant effect. On the other hand, it is volatile and insoluble and is a skin irritant. In this case, nanostructured systems have been successfully employed as a drug carrier for skin diseases since they improve both biological and pharmaceutical properties of active compounds. The cytotoxic, antioxidant, and anti-inflammatory effects of EUG were assessed in human neutrophils and keratinocytes. Additionally, polymeric nanocarries (NCEUG) were prepared to improve the chemical and irritant characteristics of EUG. EUG presented apparent safety and antioxidant and anti-inflammatory effects on human neutrophils, but presented cytotoxic ...
Naunyn-Schmiedeberg's Archives of Pharmacology, 2016
In a previous study, we performed the chemical characterization of a polyvinyl alcohol (PVA) memb... more In a previous study, we performed the chemical characterization of a polyvinyl alcohol (PVA) membrane supplemented with latex proteins (LP) displaying wound healing activity, and its efficacy as a delivery system was demonstrated. Here, we report on aspects of the mechanism underlying the performance of the PVA-latex protein biomembrane on wound healing. LP-PVA, but not PVA, induced more intense leukocyte (neutrophil) migration and mast cell degranulation during the inflammatory phase of the cicatricial process. Likewise, LP-PVA induced an increase in key markers and mediators of the inflammatory response (myeloperoxidase activity, nitric oxide, TNF, and IL-1β). These results demonstrated that LP-PVA significantly accelerates the early phase of the inflammatory process by upregulating cytokine release. This remarkable effect improves the subsequent phases of the healing process. The polyvinyl alcohol membrane was fully absorbed as an inert support while LP was shown to be active. It is therefore concluded that the LP-PVA is a suitable bioresource for biomedical engineering.
Evidence-Based Complementary and Alternative Medicine, 2015
Plumeria rubra(Apocynaceae) is frequently used in folk medicine for the treatment of gastrointest... more Plumeria rubra(Apocynaceae) is frequently used in folk medicine for the treatment of gastrointestinal disorders, hepatitis, and tracheitis, among other infirmities. The aim of this study was to investigate the gastroprotective potential of a protein fraction isolated from the latex ofPlumeria rubra(PrLP) against ethanol-induced gastric lesions and describe the underlying mechanisms. In a dose-dependent manner, the pretreatment with PrLP prevented ethanol-induced gastric lesions in mice after single intravenous administration. The gastroprotective mechanism of PrLP was associated with the involvement of prostaglandins and balance of oxidant/antioxidant factors. Secondarily, the NO/cGMP/KATPpathway and activation of capsaicin-sensitive primary afferents were also demonstrated as part of the mechanism. This study shows that proteins extracted from the latex ofP.rubraprevent gastric lesions induced in experimental animals. Also, the results support the use of the plant in folk medicine.
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