Improving Oxidative Stability of Cosmetic Emulsions with Plant Extracts: Current Status and Potential.

There are increasing demands for cosmetic emulsions with natural active components such as plant extracts because of their myriad benefits. Quality of cosmetic emulsions may be affected by distribution and storage processes, which can lead to peroxidation of lipid components. Lipid peroxidation results in undesirable alterations in efficacy, texture, and appearance of the cosmetic product, thus indicating a need to find a safe and potent compound to be added in products to postpone oxidation processes. In that sense, the current article gives an overview of parameters influencing oxidative stability of emulsions, as well as methods for assessing the oxidative stability. Emphasis is given to the usage of plant extracts rich in phenolics for improving oxidative stability of cosmetic emulsions. Application of plant extracts in cosmetic emulsion is promising because of their significant antioxidant properties which may delay lipid peroxidation during storage. Plant species are a valuable source of biologically active compounds that might be exploited in the cosmetic and pharmaceutical industry.

Effects of rivaroxaban and dabigatran on global hemostasis in patients with atrial fibrillation.

: The study was aimed to evaluate the effects of two standard doses of rivaroxaban and dabigatran on global hemostatic assays in patients with atrial fibrillation. The study included 52 patients treated with rivaroxaban (15/20 mg), 50 on dabigatran (110/150 mg) and 20 healthy individuals. Platelet-poor plasma was used for determination of three global hemostatic assays, namely endogenous thrombin potential (ETP), calibrated automated thrombogram (CAT) and overall hemostasis potential (OHP). Rivaroxaban and dabigatran reduced ETP (P < 0.01) although OHP (P < 0.05) was diminished only by dabigatran. Strong correlations were noticed between ETP parameters and the plasma concentrations of rivaroxaban (ETP, r = -0.51; c-max, r = -0.85; t-lag, r = 0.83; t-max, r = 0.66) as well as with plasma concentration of dabigatran (ETP, r = -0.75; c-max, r = -0.74; t-lag, r = 0.73; t-max, r = 0.52). Analysis of dabigatran concentrations under 50 ng/ml showed that ETP parameter has area under the concentration-time curve-receiver operating characteristic value of 0.879 (95% confidence interval 0.776-0.980). Dabigatran treatment paradoxically increased area under the concentration-time curve and peak values although rivaroxaban decreased peak values (P < 0.01). However, significant correlation between CAT parameters and plasma concentration of both direct oral anticoagulants was not observed. We confirmed that the CAT assay is inappropriate for estimation of dabigatran effects and is not fully sensitive as regards rivaroxaban. The ETP assay can potentially be the appropriate method for estimation of global hemostatic capacity as regards both direct oral anticoagulants. The role of OHP needs to be confirmed in additional studies. ETP parameter of chromogenic assay has promising potential in exclusion of high plasma concentrations of dabigatran.

Cardioprotective effects of Galium verum L. extract against myocardial ischemia-reperfusion injury.

The aim of our study was to determine a chemical composition of methanol extract of Galium verum as well as to assess its effects on functional recovery and redox status of isolated rat heart after ischemia. Rats were divided into control and G. verum group, which included animals treated with 500 mg/kg of methanol extract of G. verum for 28 days. Parameters of heart function and oxidative stress markers were estimated. Cell morphology was evaluated by hematoxylin and eosin (HE) staining. Our results demonstrated for the first time that G. verum extract preserved cardiac contractility, systolic, and diastolic function as wells as structural damage of the heart after ischemia. Furthermore, G. verum extract modulated the activity of antioxidant enzymes and alleviated the production of pro-oxidants.

Preconditioning with hyperbaric oxygen and calcium and potassium channel modulators in the rat heart.

The aim of this study was to establish the effect of combined therapy with hyperbaric oxygen (HBO2) therapy and verapamil, amlodipine or nicorandil on functional recovery and oxidative stress markers after ischemia in the isolated rat heart. The study included 48 rats (Wistar albino, male gender, eight weeks old, body weight 200±50g). All animals were exposed to HBO2 treatment over 14 days. Isolated heart rats were perfused by the Langendorff retrograde method at a constant coronary pressure of 70 cm H2O. After stabilization period the hearts were divided into the following groups: HBO2 group (animals exposed to only HBO2 preconditioning); HBO2 + verapamil; HBO2 + amlodipine; andHBO2 + nicorandil (animals pretreated with HBO2 and appropriate pharmacological agent). Afterward, the hearts in all groups were subjected to 20-minute global ischemia and 30-minute reperfusion. Parameters of heart function were registered, including maximum and minimum rate of pressure development, systolic and diastolic left ventricular pressure, heart rate and coronary flow. Levels of pro-oxidants such as index of lipid peroxidation, measured as thiobarbituric acid-reactive substances, nitrites, levels of superoxide anion radicals and hydrogen peroxide were determined in coronary venous effluent. Changes in cardiac tissue were evaluated by hematoxylin and eosin staining. Obtained results clearly indicate that blockage of calcium channel or the activation of adenosine triphosphate-sensitive potassium (KATP) in combination with HBO2 prevented ischemia/reperfusion-induced cardiac deleterious effects, thus contributing to improvement of functional recovery of the heart. However, future studies are certainly necessary for better understanding the mechanisms through which combination of these two maneuvers of preconditioning triggers cardioprotection.

Impact of hyperbaric oxygenation on oxidative stress in diabetic patients.

Taking into consideration that a high concentration of oxygen can express toxic effects due to production of reactive oxygen species (ROS), the aim of our investigation was to establish the influence of hyperbaric oxygenation on oxidative stress parameters and antioxidant enzymes in patients with diabetes mellitus (DM) type 2. Investigation included 50 patients with DM type 2 divided into two groups. The first group consisted of 25 patients, mean age 70 years, mean duration of illness 12 years and without manifest peripheral vascular complications (Wagner 0). The second group consisted of 25 patients, mean age 74 years, mean duration of illness 17 years and with manifest peripheral vascular complications (Wagner 1-5). All patients underwent the same therapeutic protocol, which included 10 hyperbaric oxygenation therapies, once a day for a duration of 60 minutes, with an average partial oxygen pressure of 1.7 atmospheres absolute (ATA). In blood samples the following parameters of redox balance were determined: levels of nitrites (NO2-), index of lipid peroxidation (TBARS), superoxide anion radical (O2-), hydrogen peroxide (H2O2) and antioxidant enzymes superoxide dismutase (SOD) and catalase (CAT). Our results clearly show that hyperbaric oxygen (HBO2) therapy does not have a pro-oxidative effect. Additionally, it seems that this procedure strongly mobilized the antioxidant enzyme system, thus improving defense from oxidative damage. All significant data are marked as P ⟨0.05. Our results have shown that in terms of ROS production, HBO2 can be safe to use in patients suffering from DM type 2 with or without vascular complications.