Anti-Inflammatory, Antimicrobial, Antioxidant and Photoprotective Investigation of Red Propolis Extract as Sunscreen Formulation in Polawax Cream.

Many activities have been described for propolis, including, antiviral, antibacterial, antifungal, anti-inflammatory, immunoregulatory, antioxidant and wound healing properties. Recently, propolis has been highlighted due to its potential application in the pharmaceutical and cosmetic industries, motivating a better understanding of its antioxidant and anti-inflammatory activities. Propolis and its main polyphenolic compounds presented high antioxidant activity, and effectiveness as broad spectrum UVB and UVA photoprotection sunscreens. Through a qualitative phytochemical screening, the ethanolic red propolis extracts (EEPV) (70% at room temperature and 70% at a hot temperature) presented a positive result for flavonoids and terpenoids. It presented an antioxidant activity for reducing 50% of DPPH of 17 and 12 µg/mL for extraction at room temperature and at a hot temperature, respectively. The UPLC-QTOF-MS/MS analysis allowed the annotation of 40 substances for EEPV-Heated and 42 substances for EEPV-Room Temperature. The IC50 results of the ABTS scavenging activity was 4.7 µg/mL for both extractions, at room temperature and at a hot temperature. Additionally, we also evaluated the cytotoxic profile of propolis extracts against macrophage (RAW 264.7 cells) and keratinocytes (HaCaT cells), which showed non-cytotoxic doses in cell viability assays even after a long period of exposure. In addition, propolis extracts showed antibacterial activity for Gram-positive bacteria (Staphylococcus aureus and Staphylococcus epidermidis), demonstrating potential biological activity for the creation of formulations aimed at disease control and prevention.

Nanohybrid composed of graphene oxide functionalized with sodium hyaluronate accelerates bone healing in the tibia of rats.

This study synthesized and characterized a nanohybrid composed of graphene oxide (GO) functionalized with sodium hyaluronate (HY) (GO-HY), evaluated its effect in vitro and determined its osteogenic potential in vivo. The synthesized nanohybrid was analyzed by Scanning electron microscopy (SEM), Raman spectrometry, Thermogravimetry, Fourier-transform infrared (FTIR) spectroscopy and X-ray diffraction. MC3T3-E1 cell viability was assessed by MTT assay in 48 and 72 h. Bone defects were created in tibia of 40 Wistar rats and filled with blood clot (control), 1% HY, GO (50, 100 and 200 µg/mL) and the nanohybrid (50, 100 and 200 µg/mL). After 7 and 14 days, histomorphometric analysis was carried out to assess osteogenic potential of the nanohybrid. Immunohistochemical analysis evaluated the expression of vascular endothelial growth factor (VEGF) in bone defects. Thermogravimetric analysis, Raman and FTIR spectrometry confirmed the functionalization of GO with HY by covalent bonds. Five µg/mL concentrations of the nanohybrid did not alter the viability of the MC3T3-E1 cells. Histomorphometric analysis demonstrated that the nanohybrid at 100 µg/mL significantly accelerated the bone repair in tibia of rats when compared to controls (p < 0.01). Immunohistochemical analysis showed a significantly less intense VEGF expression in tibia treated with the nanohybrid when compared to controls (p < 0.05). The nanohybrid composed of GO functionalized with HY was able to induce the acceleration of the tissue regeneration process in bone defects created in the tibia of rats. This novel nanohybrid is a promising material for the field of bone tissue engineering.