Francisco Gómez-García

An experimental study of bisphosphonate-induced jaws osteonecrosis in Sprague-Dawley rats.

OBJECTIVE Patients undergoing treatment with bisphosphonates may develop jaw lesions consisting mainly of bone necrosis. The present study describes a model of maxillary osteonecrosis in Sprague-Dawley rats, applying bisphosphonates and examines the changes occurring after tooth extraction. MATERIAL AND METHODS A total 200 animals were included in a randomized prospective study involving the following groups: group I (control, 20 rats without drug treatment), group II (60 animals administered dexamethasone 1 mg/kg/day for 7, 14 and 21 days, in subgroups of 20 animals each), group III (60 animals administered pamidronate daily at a dose of 3 mg/kg) and group IV (60 animals administered pamidronate and dexamethasone). In all groups, molar extraction was carried out on the right upper maxillary or mandibular side 8, 15 and 22 days after the start of dosing. The rats were killed 14 and 28 days after extraction in all groups. RESULTS A total of 18 cases of osteonecrosis were recorded in the group administered pamidronate and dexamethasone. Osteonecrosis affected the upper maxilla in 10 cases and the mandible in eight cases, and was circumscribed to the extraction zone in all cases. Osteonecrosis was not seen in any of the other groups. CONCLUSIONS The administration of pamidronate and dexamethasone in rats subjected to molar extraction increases the risk of osteonecrosis.

Perioperative antibiotic regimen in rats treated with pamidronate plus dexamethasone and subjected to dental extraction: a study of the changes in the jaws.

PURPOSE Osteonecrosis of the jaws is a well-known condition associated with long-term bisphosphonate use. This study analyzed the prophylactic effect of antibiotic treatment in Sprague-Dawley rats treated with pamidronate plus dexamethasone and subjected to oral surgery in the form of dental extraction. MATERIALS AND METHODS One hundred twenty animals were included in a randomized prospective study. Animals in group I (n = 60) were treated with dexamethasone 1 mg/kg and pamidronate 3 mg/kg 3 times per week for 7, 14, and 21 days. All were subjected to right mandibular or maxillary molar extraction 8, 15, and 22 days after the start of dosing. Animals in group II (n = 60) received the same treatment except for the addition of penicillin 0.1 mL/kg per day for 3 days before and 4 days after extraction. Rats in the 2 groups were sacrificed 14 and 28 days after extraction. A clinical and histologic evaluation was performed. RESULTS In group I, osteonecrosis was documented in 18 cases (34.6%; affecting the upper and lower jaws in 10 and 8 cases, respectively). In group II, osteonecrosis was documented in 5 cases (9.61%; affecting the upper and lower jaws in 3 and 2 cases, respectively). The difference between the 2 groups was statistically significant (P = .002). CONCLUSIONS The adoption of preventive measures (antibiotic prophylaxis) in invasive dental procedures results in a significant decrease in osteonecrosis of the jaws associated with bisphosphonate use.

Topical Curcumin for the Healing of Carbon Dioxide Laser Skin Wounds in Mice

OBJECTIVE The purpose of this study was to evaluate the effect of topical curcumin on the healing of skin wounds produced by the CO(2) laser in an animal model. METHODS A prospective, randomized study was made of 90 mice assigned to three groups (30 animals per group), with the creation of 6-mm incisions in the skin of the dorsal region by means of the CO(2) laser. A total of 270 wounds were made (3 wounds by animal). No product was applied to the resulting wound in group I (control group); vehicle was applied in group II (5 mg/day by wound); and topical curcumin was applied to the mice in group III (5 mg/day by wound). Re-epithelialization and inflammation of the wounds were measured from histological sections of wounds, after 2, 7, and 14 days. RESULTS Two days after production of the wounds, most of the latter showed incomplete re-epithelialization. After 7 days, 73.33% of the wounds treated with curcumin presented re-epithelialization covering the entire wound, with irregular thickness; nevertheless, only 37.50% of the wounds in control group and 41.67% in the vehicle group showed this degree ot re-epithelialization. After 14 days, all the wounds had completed re-epithelization. No significant differences were observed regarding resolution of the inflammatory process in any of the study groups after 2, 7, and 14 days. CONCLUSIONS This study shows that topical curcumin applied to CO(2) laser-induced skin wounds may be useful, because improved re-epithelialization is observed after 7 days.

Effect of the phenolic compounds apigenin and carnosic acid on oral carcinogenesis in hamster induced by DMBA

OBJECTIVE To investigate oral carcinogenesis in hamster induced by the topical application of 7,12-dimethyl benzanthracene (DMBA) to evaluate the different lesions produced and the possible preventive effects of the phenolic compounds apigenin (flavone) and carnosic acid (diterpene). MATERIALS AND METHODS Thirty-two Syrian hamsters were divided into three groups: I: 0.5% DMBA (n = 12); II: 0.5% DMBA + potassium apigenin (n = 8); III: 0.5% DMBA + carnosic acid (n = 12). All the animals were sacrificed after 11 weeks, and a macroscopic and light microscopic study was made of the lesions. RESULTS The largest number of neoplasms, showing the most aggressive biological behavior, corresponded to the control group. The group treated with potassium apigenin ranked second in tumor incidence, although the tumors were not very aggressive behavior. In the group treated with carnosic acid, only one malignancy was recorded, showing the smallest volume of all the recorded tumor lesions. CONCLUSIONS Our findings indicate that both potassium apigenin and carnosic acid have chemoprotective effects against carcinogenesis induced by DMBA in hamster.

Effect of curcumin and irradiation in PE/CA-PJ15 oral squamous cell carcinoma

Abstract Objective. An in vitro study was made to evaluate the effect of curcumin and irradiation upon oral squamous cell carcinoma. Materials and method. Curcumin was administered at doses of 3, 3.75, 4.50 and 5.25 μM in PE/CA-PJ15 oral squamous cell carcinoma cultures irradiated with different doses (1, 2.5 and 5 Gy), followed by evaluation of the effects upon cell viability after 24, 48 and 72 h, based on the MTT colorimetric test. Results. The application of curcumin to the PECA/PJ15 tumor cells during 24, 48 and 72 h of incubation without irradiation exerted an inhibitor effect upon cell viability. The curcumin concentration at which the inhibition of cell viability proved maximum was 5.25 μM, with statistically significant differences for 24 h (p = 0.002), 48 h (p < 0.001) and 72 h of incubation (p < 0.001). In contrast, the combination of curcumin and irradiation exerted a synergic effect—the greatest effects in relation to cell viability being recorded with a curcumin concentration of 3.75 μM and 5 Gy of irradiation, in the studied cell line. Conclusions. Curcumin increases cytotoxic activity in the PE/CA PJ15 cell line, while the combination of curcumin and irradiation exerts a synergic effect.

Safety evaluation and nutritional composition of a Fraxinus excelsior seed extract, FraxiPure™

A natural extract obtained from the seeds of Fraxinus excelsior L. (FraxiPure™) has been previously reported to reduce glycemia in animal models and in humans. The objective of this work was to evaluate the safety of FraxiPure™ at in vitro, in vivo and human levels. In addition, nutritional analyses revealed an extract high in carbohydrates, with minor levels of protein, dietary fiber, glucose and sucrose. IC(50) and IC(90) values of 1.447 and 2.530 mg/mL, respectively, after 72 h incubation were calculated using the MTT assay. FraxiPure™ conferred a magnitude of protection of 69.2% against the formation of micronuclei in irradiated human lymphocytes as determined by the micronucleus assay. An LD(50) of greater than 2500 mg/kg was concluded following an acute oral toxicity study in Sprague-Dawley rats. A human safety evaluation in a double-blind, placebo-controlled parallel study of 100 healthy volunteers revealed no significant differences between daily consumption of 1000 mg of FraxiPure™ for 90 days and placebo (maltodextrin) for any of the biochemical or hematological parameters studied. Numbers of adverse events were similar in both groups, and were deemed mild to moderate. These results demonstrate, for the first time, the safety and tolerability of FraxiPure™ for consumption in healthy subjects.

Radioprotective effects of lycopene and curcumin during local irradiation of parotid glands in Sprague Dawley rats

Radiotherapy effectively treats cancers of the head and neck. We investigated the possible protective effects of lycopene and curcumin on the parotid glands of 40 female Sprague Dawley rats during irradiation. The study followed European Union regulations 86/609/EEC, 2010/63/EU for animal experimentation. The animals were divided into 4 groups: those treated with curcumin and radiation, those treated with lycopene and radiation, those treated with dimethyl sulphoxide (DMSO) and radiation, and those treated with radiation alone. All compounds were given intraperitoneally the day before irradiation. The total dose of radiation was 20Gy. Morphological and histopathological analyses showed less cell necrosis in the group treated with curcumin than in the other groups, but the difference was not significant. Analysis of structural damage to the parotid ducts and vacuolisation showed significant differences among all groups (p=0.023, p<0.01). Lycopene and curcumin given 24 hours before irradiation reduced the structural damage to the salivary glands. Further studies are needed to confirm these findings.

Effects of potassium apigenin and verbena extract on the wound healing process of SKH-1 mouse skin

Tissue repair is a complex process, which may be favoured or inhibited by different factors. Potassium apigenin (AP) and other flavonoids present in verbena extract (PLX®) possess powerful anti‐inflammatory properties. The aim of this study was to evaluate the effects of topical treatment with AP and PLX gels on wounds inflicted on SKH‐1/CRL mice. Forty‐eight SKH‐1 mice were used (4 groups with 12 animals each), which were subjected to wound excision with a round scalpel, 4 mm in diameter, on the dorsal skin. The animals were divided into four groups: Group I received topical applications of apigenin gel; Group II received PLX gel; Group III received vehicle gel; Group IV acted as control. Wound contraction, reepithelialisation, inflammation and neovascularisation (by means of immunohistochemical staining with anti‐laminin) were recorded at study periods established at 2, 7 and 14 days. Reepithelialisation was faster in Groups I and II at 7 days (56·25% grade 3 and 43·75% grade 4) compared with the other groups. The degree of inflammation showed improvement with a tendency towards statistical significance in Groups I and II at 2 and 7 days. Anti‐laminin staining was more intense in the group treated with PLX at the 2‐ and 7‐day periods. Topical treatment with PLX gel improved the degree of reepithelialisation and inflammation, and favoured neo‐vascularisation of the wounds at 2 and 7 days following surgery.

Chemopreventive potential of phenolic compounds in oral carcinogenesis.

OBJECTIVE To evaluate the chemopreventive potential of phenolic compounds - potassium apigenin, cocoa, catechins, eriocitrin and rosmarinic acid in oral carcinogenesis induced in hamsters by means of the topical application of 7,12-dimethylbenz(a)anthracene(DMBA). STUDY DESIGN An experimental study at the University of Murcia. METHODS 50 male Syrian hamsters (Mesocricetus auratus) were divided into five groups of ten: Group I (control group): 0.5% DMBA; Group II: 0.5% DMBA+1.1mg/15ml potassium apigenin; Group III: 05% DMBA+2.5mg/15ml cocoa catechins; Group IV: 0.5% DMBA+6mg/15ml eriocitrin; Group V: 0.5% DMBA+1.3mg/15ml rosmarinic acid. The flavonoids were administered orally. All the animals were sacrificed after 12 weeks. Macroscopic, microscopic and immunohistochemical (PCNA and p53) analyses of the lesions were performed. RESULTS All the groups treated with phenolic compounds showed lower incidences of tumour, greater differentiation and lower scores in the tumour invasion front grading system in comparison with the control group. Potassium apigenin and rosmarinic acid achieved the best results, the former considerably reduced the carcinoma tumour volumes developed and both significantly reduced the intensity and aggression of the tumours. Immunoexpression of PCNA and p53 were significantly altered during DMBA-induced oral carcinogenesis. CONCLUSIONS Animals treated with phenolic compounds, particularly potassium apigenin and rosmarinic acid, showed a lower incidence of tumours.

Preventive Effect of a Fraxinus Excelsior L Seeds/Fruits Extract on Hepatic Steatosis in Obese Type 2 Diabetic Mice

Background: Non-alcoholic fatty liver is recognized as one of harmful consequences of the metabolic syndrome and hepatocytes steatosis is well connected with loss of insulin sensitivity, impaired glucose tolerance and can lead to impaired fasting glucose and type2 diabetes mellitus. Fraxinus excelsior L. seed extract has been used as traditional folk medicine by Mediterranean population and Glucevia®, a natural extract of Fraxinus excelsior L. derived from seeds/fruits of the plant and standardized to 10% Nuzhenide and GI3, has been previously reported to regulate glucose homeostasis in healthy overweight people. Methods: The effect of seven-month administration of Glucevia® on liver parameters was investigated in a diabetic mouse strain (BKS ++Lepr db (db/db)). The severity of fatty change and grading of hepatic steatosis were determined by estimating the fat hepatocytes contain in animals fed with a control diet or with a control diet supplemented with 0.07 % (w/w) of the extract. Results: Glucevia® was shown to significantly reduce fatty liver in diabetics mice (-54%; p<0.05). A concomitant improvement in alkaline phosphatase (ALP) levels and in aspartate aminotransferase/alanine aminotransferase (AST/ALT) ratio were observed between groups (p<0.05). A significant decrease in insulin plasma level (-22%; p<0.05) was measured in Glucevia® group leading to an improvement of HOMA-IR between groups (p<0.001) while no significant change of fasting blood glucose was observed between group. Conclusion: The results observed supports the potential hepatoprotective function of Glucevia®, which seems to prevent fatty liver formation in type 2 diabetes mice model.