Development and evaluation of sunscreen creams containing morin-encapsulated nanoparticles for enhanced UV radiation protection and antioxidant activity.

The objective of present work was to develop novel sunscreen creams containing polymeric nanoparticles (NPs) of morin. Polymeric NPs containing morin were prepared and optimized. The creams containing morin NPs were also prepared and evaluated. Optimized NPs exhibited particle size of 90.6 nm and zeta potential of -31 mV. The entrapment efficiency of morin, within the polymeric NPs, was found to be low (12.27%). Fourier transformed infrared spectroscopy and differential scanning calorimetry studies revealed no interaction between morin and excipients. Transmission electron microscopy and atomic force microscopy revealed that the NPs were spherical in shape with approximately 100 nm diameter. Optimized NPs showed excellent in vitro free radical scavenging activity. Skin permeation and deposition of morin from its NPs was higher than its plain form. Different sunscreen creams (SC1-SC8) were formulated by incorporating morin NPs along with nano zinc oxide and nano titanium dioxide. SC5 and SC8 creams showed excellent sun protection factor values (≈40). In vitro and in vivo skin permeation studies of sunscreen creams containing morin NPs indicated excellent deposition of morin within the skin. Morin NPs and optimized cream formulations (SC5 and SC8) did not exhibit cytotoxicity in Vero and HaCaT cells. Optimized sunscreen creams showed excellent dermal safety. SC5 and SC8 creams demonstrated exceptional in vivo antioxidant effect (estimation of catalase, superoxide dismutase, and glutathione) in UV radiation-exposed rats. The optimized sunscreen creams confirmed outstanding UV radiation protection as well as antioxidant properties.

A study on the role of (+)-catechin in suppression of HepG2 proliferation via caspase dependent pathway and enhancement of its in vitro and in vivo cytotoxic potential through liposomal formulation.

Catechin is a known hepatoprotective and anticancer agent but has limited bioavailability. Its apoptotic signaling pathway in human hepatocellular carcinoma is vaguely explored. Thus, this study was designed to explore cytotoxicity by MTT assay, induction of apoptosis via DNA fragmentation, nuclear staining, bivariate flow cytometric analysis using annexin V- FITC and propidium iodide, cell cycle analysis and apoptotic markers by RT-PCR and western blotting in HepG2 cells. To increase the bioavailability and selectivity to cancer cells, various liposomes of catechin viz., conventional, charged and PEGylated forms were prepared by film hydration method and evaluated for cytotoxicity in vitro in HepG2 cells and in in vivo in EAC-induced liquid tumor model. Catechin and catechin liposomes inhibited the growth of HepG2 cell lines at concentrations 100-200 µg mL(-1) depending on the length of exposure. It induced apoptosis and inhibited G2/M phase in cell cycle analysis. Catechin downregulated Bcl-2, initiated the release of cytochrome c into the cytosol and upregulated Bax, caspase-3,-9 and p53 in the HepG2 cells. Catechin and its liposomal formulation, at a dose of 200mg/kg body weight was found to be significantly (p<0.05) effective in inhibiting percentage increase in body weight and enhancing the mean survival time. Deviated hematological parameters, antioxidant parameters (superoxide dismutase, catalase and lipid peroxidation) and LFT in tumor bearing mice were found to be significantly (p<0.05) restored towards normal after treatment with catechin and its liposomes.