Antioxidant, antibacterial and in vivo dermal wound healing effects of Opuntia flower extracts.

Opuntia ficus-indica flowers are used for various medicinal purposes. The aims of the present investigation were to evaluate biological properties of O. ficus-indica flowers extracts and to investigate its antioxidant and antibacterial activities and its ability to enhance wound healing. The wound healing activity of the mucilaginous and methanol extracts of O. ficus-indica flowers were assessed using excision wound model in rats. After thirteen days of treatment by both extracts, a beneficial effect on cutaneous repair was observed as assessed by the acceleration of wound contraction and remodeling phases. Histopathological studies of the granulation tissue indicated that the derma is properly arranged with the Opuntia flowers extract, compared with the control group. The mucilage extract was more effective than the methanol extract, but both showed significant results compared with the control. Such investigation was supported by the efficiency of the methanolic and mucilage extract as antimicrobial and antioxidant. Indeed, the extracts showed a potential antioxidant activity determined by different test systems, namely DPPH radicals scavenging activity, trolox equivalent antioxidant capacity, reducing power, ß-carotene bleaching assay and metal chelating activity and exhibited significant antibacterial activity against almost all tested bacteria.

Microstructure, rheological and wound healing properties of collagen-based gel from cuttlefish skin.

Collagen-based biomaterials are of the utmost importance for tissue engineering and regenerative medicine. The aims of the present investigation were to evaluate structural and rheological properties of collagen-based gel obtained from cuttlefish skin, and to investigate its ability to enhance wound healing. Scanning electron microscopy of resulted gel showed a dense fibrillar microstructure with high interconnection network with a smaller pore size. In addition, the rheological characterization of collagen gel showed an excellent reversibility, when subjected to a temperature variation. Moreover, in the wound-healing study, topical application of collagen based gel increased significantly the percentage of wound closure over a period of 12 days, when compared to the untreated and CICAFLORA(®)-treated groups. Wound-healing activity of collagen gel was confirmed by histopathology study. Thus, cuttlefish collagen based gel might be useful as a wound healing agent.

Lack of nephrotoxicity following 15-day therapy with high doses of colistin in rats.

BACKGROUND: Recent studies suggest that the incidence and severity of systemic toxicity due to colistin administration appear to be overstated. The objective of this study was to investigate colistin-induced nephrotoxicity in Wistar rats. MATERIAL/METHODS: Eighteen adult Wistar rats were divided into three groups: group I (controls, vehicle, n=6) rats were injected intramuscularly (i.m.) with physiological sodium chloride solution and groups II and III (colistin, n=6 each) rats were treated with colistin at a dose of 150,000 or 300,000 IU/kg body weight per day i.m, respectively. The drug injections were applied for 15 days. Twelve hours after the last injection the rats were sacrificed. The kidneys were quickly removed and blood samples were collected. Microscopic examination of the kidneys and measurements of serum creatinine and blood urea nitrogen concentrations were performed. RESULTS: The mean urea nitrogen concentrations were 5.95+/-0.58, 5.75+/-0.61, and 5.77+/-0.87 mmol/l and the mean serum creatinine concentrations were 45.5+/-1.87, 43+/-1.79, and 44+/-2.19 micromol/l in groups I, II, and III, respectively, without any statistical differences between the groups. Exposure to colistin did not cause any histological change in the kidney structure. CONCLUSIONS: These results suggest that colistin, when administered alone at usual doses, may not cause nephrotoxicity.