Creation of an adequate animal model of hyperuricemia (acute and chronic hyperuricemia); study of its reversibility and its maintenance.

AIM: Hyperuricemia is defined by the European Rheumatology Society as a uric acid level greater than 6 mg/dl (60 mg/l or 360 µmol/l). Our goal was to evaluate the hypouricemic effect of nettle. For this reason, we have first of all try to create an hyperuricemic animal model which is very suitable because at the level of literature there is not an exact model, there are many models and our objective is to set an adequate model. MATERIALS AND METHODS: An attempt has been made to test acute and chronic hyperuricemia by varying the duration and method of induction of potassium oxonate. Similarly, attempts have been made to induce chronic hyperuricemia through an animal and vegetable diet. The reversibility of hyperuricemia was tested with a maintenance protocol. KEY FINDINGS: For the creation of the hyperuricemia model, it has been shown that acute hyperuricemia cannot be induced by short administration of potassium oxonate and persistent chronic hyperuricemia can be induced only after daily administration of oxonate of potassium by intraperitoneal injection for 15 days. Indeed, hyperuricemia was reversible after stopping the administration of potassium oxonate. The high-purine diet is also capable of inducing chronic hyperuricemia but to a less extent. SIGNIFICANCE: After creating an adequate model of hyperuricemia while setting the dose of potassium oxonate, route of administration and duration. A maintenance protocol was followed which subsequently made it possible to deduce that the daily administration of potassium oxonate must be continued to maintain the hyperuricemia.

Screening of analgesic activity of Tunisian Urtica dioica and analysis of its major bioactive compounds by GCMS.

The present study was aimed to evaluate the analgesic properties of Urtica dioica (UD) and to profile phytochemicals by gas chromatography-mass spectrometry (GC-MS). The ethanolic extracts were prepared by maceration method and extraction using rotary evaporator. The analgesic activity was analysed by hot plate method, formalin test, acetic acid-induced writhing test and the tail-flick test with different doses of the ethanolic extract. In all tests, the leaf's ethanolic extract exhibited significant analgesic activity (p < .001) at a dose of 400 mg/kg. Even with a low dose, we noticed an analgesic activity with many tests. The GC-MS analysis of the ethanol extract of leaf revealed many compounds; 2-methyltetradecane dodecane, 2,6,11-trimethyl-; 2,6,11-trimethyldodecane, and trimethylhexane which are pharmaceutically the most important. These findings justify that UD can be a valuable natural analgesic source which seemed to provide potential phototherapeutics against various ailments. The analysis of ethanolic extract of UD by GCMS revealed the presence of several compounds including polyphenols, flavonoids, triterpenes which can explain the analgesic effect of UD and its mechanism of action. Hence, UD could be another therapeutic alternative for relieving pain and for minimising the use of drugs that have long-term secondary effects.

The healing effect of Pistacia lentiscus fruit oil on laser burn.

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.

The effect of natural extracts on laser burn wound healing.

BACKGROUND: Despite the achievements in modern medicine, there is no effective natural treatment of second-degree burns till now. Therefore, the purpose of this study was to assess the wound-healing efficiency of three extracted oils, from the prickly pear, pumpkin and linseed on partial-thickness burns induced by fractional CO2 laser (an innovative up-to-date technique) in rats. MATERIALS AND METHODS: Thirty rats completing partial-thickness burns by fractional CO2 laser were randomly divided into five groups. The burns were measured, photographed, and topically treated daily with saline solution, "CYTOL BASIC," pumpkin-, linseed-, and prickly pear-extracted oils (0.52 µL/mm(2) of oil) until day 7. The response to treatments was assessed by macroscopic, histologic, and biochemical parameters. RESULTS: Due to their chemical composition, the extracted oils showed significant improvements over the control and reference groups during the trial for both general wound appearance and crusting. On day 7, the prickly pear, linseed, and pumpkin oils showed a significant decrease in the healing time (0 cm(2), 0.15 cm(2), and 0.18 cm(2), respectively) when compared to the control and reference groups (1.49 cm(2) and 0.85 cm(2)). Histologic assessment of the prickly pear oil-treated group revealed good healing proprieties compared with the other groups. The collagen content in prickly pear oil-treated group was found to be significantly greater (270.67 ± 7.48) than that in all other groups. CONCLUSIONS: Our experiment has shown, for the first time, a scientific evidence of the efficiency of extracted oils of prickly pear, pumpkin, and linseed on partial-thickness burns.

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.

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/mm(2) 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.

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.

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.

Mutational analysis of the MECP2 gene in Tunisian patients with Rett syndrome: a novel double mutation.

Rett syndrome is a severe disorder characterized by loss of acquired skills after a period of normal development in infant girls. It is caused mainly by mutations in the MECP2 gene. In this study, we reported mutations in the MECP2 gene in 7 Tunisian patients with classic Rett syndrome. The results showed the presence of a double mutation in 1 patient: p.R306C and c.1461+98insA, which create a new hypothetical polyadenylation site in the 3(')UTR of the MECP2 gene. We also detected in another patient a new variant c.1461+92C>G in the 3(')UTR located previous to 34 bp from the polyadenylation site with a score of 4.085. This variation is located in a hypothetical splicing enhancer with a score of 1.96277 according to the ESE finder program. In the remaining 5 patients, we found 2 common mutations: p.T158M in 4 individuals and p.R168X in only 1 girl.