Sana Bardaa

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.

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, β-carotene bleaching assay and metal chelating activity and exhibited significant antibacterial activity against almost all tested bacteria.

Rhelogical, dermal wound healing and in vitro antioxidant properties of exopolysaccharide hydrogel from Pseudomonas stutzeri AS22.

The in vitro antioxidant activity and the in vivo wound healing performance of the exopolysaccharide EPS22, produced by Pseudomonas stutzeri AS22, were investigated. Antioxidant activity was evaluated by three different tests. The scavenging effect on DPPH radicals at a concentration of 1mg/ml was 80±1.41%. The reducing power reached a maximum of 1.26±0.02 at 2 mg/ml. Moreover, EPS22 showed good chelating ability and chelated almost 88.5±0.7% of ferrous ions at 0.75 mg/ml. The rheological characterization of EPS22 gel (0.5%) showed a pseudoplastic behavior, high elasticity, good mechanical strength and stability with high water-absorption ability. The application of the EPS22 gel on dermal full-thickness excision wounds in a rat model every two days, enhanced significantly wound healing activity and a total closure was achieved after 12 days of wound induction. Further, histological examination of biopsies showed advanced tissue regeneration, characterized by the presence of well-organized stratum of both derma and epidermis.

In Vivo Evaluation of the Anti-Inflammatory Effect of Pistacia lentiscus Fruit Oil and Its Effects on Oxidative Stress

In order to find new topical anti-inflammatory agents, we had recourse to a medicinal plant. This work was designed to determine the topical anti-inflammatory effect of Pistacia lentiscus fruit oil (PLFO), using carrageenan-induced paw edema rat model, and to evaluate its effects on oxidative stress. The topical anti-inflammatory activity of PLFO was compared to Inflocine® and estimated by measuring the diameter of paw edema, for 5 hours at a 1-hour interval. After that the rats were scarified and the inflamed paw tissue was removed for the exploration of some parameters of oxidative stress and histopathology. PLFO showed a significant anti-inflammatory activity in comparison with the Inflocine. The percentages of edema inhibition were 70% and % 51.5% (p < 0.01), respectively, after five hours. The treatment with PLFO and Inflocine led to significant increases (p ≤ 0.05) in the activities of CAT, SOD, and GPX and significant decreases in the MDA level and AOPP activity in the paw tissue after Carr injection, in comparison with the Carr group. Therefore, our findings demonstrate that PLFO might accelerate the development of new drugs which could be used scientifically as a source for natural health products in the treatment of topical inflammation.

The evaluation of the healing proprieties of pumpkin and linseed oils on deep second-degree burns in rats

Abstract Context: Medicinal plants have been recognized as useful remedies for primary health care. Accordingly, Cucurbita pepo L. (Cucurbitaceae) (pumpkin) and Linum usitatissimum (L.) Griesb. (Linaceae) (linseed) which have extracted oil with prominent pharmacological properties are investigated as possible burn healing treatments. Objective: The present study assesses the healing potential of pumpkin and linseed extracted oils on rats. Materials and methods: Uniform deep second-degree burns were induced on the dorsum of 24 rats, randomly divided into four groups. The burns were measured, photographed, and topically treated with saline solution, “Cytol Centella®”, pumpkin, and linseed-extracted oils (0.52 µl/mm2 of oil) each 2 d (up until day 33). Post-burning of the 33rd day, biopsies were histologically assessed. Results: At the end of the experiment, the rat groups treated with linseed, pumpkin oils, and “Cytol Centella®” had higher percentage of wound contraction (98.68, 96.71, and 92.54%, respectively) than the control group (58.38%). Wound biopsies from rats treated with extracted oils showed the best tissue regeneration proprieties as compared with the other groups. The histomorphometric analysis of biopsies revealed that linseed oil could significantly stimulate angiogenesis (55.6% ± 7.25). The pumpkin oil, and Cytol Centella® could significantly increase the collagen production 64.9% ± 5.94, and 61.2% ± 7.36, respectively. Discussion and conclusion: Overall, our study has given for the first time scientific evidence of the healing efficiency of pumpkin and linseed oils on burn-wounds.

The healing effect of Pistacia lentiscus fruit oil on laser burn

Abstract Context: Since antiquity, Pistacia lentiscus L. (Anacardiaceae) fruit oil (PLFO) has been used as a remedy for primary health care such as burn treatment. Objective: This study assesses the healing effect of PLFO on CO2 laser fractional burn in a rat model. Materials and methods: The study was carried out on 18 adult male Wistar rats. A second-degree laser burn (wound area = 2.2 cm2) was inflicted in the dorsal region by the application of CO2 fractional laser within the following parameters; Energy level: 25 MJ and Depth level: 4. After applying laser, the rats were divided into three groups: the first was treated with saline solution, the second with a reference cream ‘CYTOL BASIC®’ (0.13 μg/mm2) and the third with PLFO (0.52 μL/mm2). All treatments were topically administered for eight days. The healing effect was assessed using macroscopic, histological and biochemical parameters. Results: After eight days, the higher percentage of wound healing contraction was observed among the PLFO-treated group (100%) followed by the ‘CYTOL BASIC®’ treated group (61.36%) and untreated group (32.27%). During the treatment, the PLFO-treated group showed less erythema, less crusting/scabbing, higher general wound appearance scores and a high content of collagen (220.67 ± 7.48 mg/g of tissue) than the other groups. Discussion and conclusion: The current study has shown, for the first time, the healing effect of PLFO on CO2 laser fractional burn. Their wound healing effect could be attributed to their antimicrobial, anti-inflammatory and antioxidant effects.

Evaluation of dermal wound healing activity and in vitro antibacterial and antioxidant activities of a new exopolysaccharide produced by Lactobacillus sp.Ca6

The present study aimed to evaluate the in vitro antibacterial and antioxidant activities and the in vivo wound healing performance of a noval exopolysaccharides (EPS-Ca6) produced by Lactobacillus sp.Ca6 strain. The results showed that EPS-Ca6 had a potential antioxidant activity determined through four different assays: DPPH scavenging activity, reducing power, β-carotene bleaching by linoleic acid assay, and Metal chelating activities. It also exhibited significant antibacterial activity against pathogenic bacteria Salmonella enterica and Micrococcus luteus. The wound healing activity of the EPS-Ca6, using excision wound model in rats, showed that this novel EPS accelerated significantly wound healing activity as compared to the control group, and a total closure was achieved after 14days of wound induction. Furthermore, histological examination of biopsies showed fully re-epithelialized wound with a complete epidermal regeneration. Overall the finding indicates that the EPS-Ca6 might be useful as a wound healing agent in modern medicine.

Antioxidant and hemolytic activities, and effects in rat cutaneous wound healing of a novel polysaccharide from fenugreek (Trigonella foenum-graecum) seeds.

The aim of this work was to evaluate the antioxidant and hemolytic activities as well as the in vivo wound healing performance of a novel polysaccharide (FWEP) extracted from fenugreek (Trigonella foenum-graecum) seeds. The antioxidant activity was evaluated in vivo and in vitro using various assays. Results showed that FWEP exhibited strong antioxidant activities but no hemolytic activity was observed towards bovine erythrocytes. The application of FWEP hydrogel on the wound site in a rat model enhanced significantly wound healing activity and accelerated the wound closure after 14days of wound induction. Histological examination also demonstrated fully re-epithelialized wound with a complete epidermal regeneration. Altogether, these evidences demonstrated that FWEP had strong wound healing potential presumably achieved through its antioxidant activities.

Chemical composition, phytochemical constituents, antioxidant and anti-inflammatory activities of Urtica urens L. leaves

Abstract Objective: The aim of this study was to investigate the chemical composition and antioxidant properties of Urtica urens L.(Uu) as well as its anti-inflammatory effect on carrageenan (CARR)-induced paw oedema in rats. Methods: The leaves were extracted using ethanol (EtOH) and water. The extracts were analysed for proximate composition and antioxidant activity using standard chemical analysis methods. Results: The proximate analysis showed that Uu leaves contained appreciable percentages of dry mass, ashes, carbohydrates, proteins, lipids, sugars, anthocyanin, carotenoid and fibre. Results showed that EtOH extract contained the highest amount of total phenolics, flavonoids, tannins, ortho-diphenols and flavonols. It decreased the paw oedema after CARR administration, and ameliorated the activities of catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GPx), and the malondialdehyde (MDA). Conclusions: Uu displayed a high potential as a natural source of minerals, phytochemicals and antioxidant properties. EtOH extract exhibited a significant inhibition against CARR-induced inflammation.