Papers by Suzana Mesquita

Biologia, 2008
Croton cajucara Benth. (‘sacaca’) is a tree of the Euphorbiaceae family, native to the Amazon reg... more Croton cajucara Benth. (‘sacaca’) is a tree of the Euphorbiaceae family, native to the Amazon region in northern Brazil, where it is widely used in the popular treatment of various diseases. Its active principle, the terpenoid trans-dehydrocrotonin, has been credited with a variety of medical properties, including antiulcer, antiinflammatory, antitumor, antimutagenic and hypoglycemic activity. In this investigation, possible mutagenic and antimutagenic effects were evaluated in treatments using methanol extract of this plant on Swiss Albino mice by examining their peripheral blood cells for micronuclei. In these tests, the material obtained by methanol extraction of C. cajucara tree bark was administered to the mice by gavage. None of the doses evaluated in this study presented mutagenicity. Analysis of the results obtained from studies evaluating antimutagenicity revealed protection against the chemotherapeutic agent cyclophosphamide for the two highest doses used.

Genetics and Molecular Biology, 2006
The plant Croton cajucara Benth. (Euphorbiaceae) is a medicinal plant from the Brazilian Amazon w... more The plant Croton cajucara Benth. (Euphorbiaceae) is a medicinal plant from the Brazilian Amazon where it is commonly known as sacaca. The principal compound isolated from C. cajucara stem-bark extracts is the clerodane-type diterpene trans-dehydrocrotonin (DCTN) which presents several biological activities, including antiulcerogenic, anti-inflammatory, hypoglycemic, antimutagenic and antitumoral activity. However, few studies have been carried out to evaluate the therapeutic potential of raw C. cajucara extracts. We studied mutagenicity and antimutagenicity effects of C. cajucara methanol extract using the micronucleus assay in bone marrow cells and the dominant lethal assay in mice submitted to subchronic treatments. The blood testosterone levels of the mice were also measured to assess the effects of the methanol extract on testes function. Statistical analysis of the data obtained in this study showed no statistically significant mutagenicity attributable to C. cajucara stem-bark extracts, nor did such extracts show antimutagenic activity at the concentrations assessed. The testosterone concentration was normal in all the mice studied.

Acta Biologica Hungarica, 2009
The study was conducted to analyze the histology of the ovaries of adults rats treated with stero... more The study was conducted to analyze the histology of the ovaries of adults rats treated with steroids, and submitted or not to physical effort. The control group consisted of females submitted to physical effort and sedentary females, both of which received a physiological solution of 0.9% saline. Treated females, sedentary or not, received 6 mg/kg of body weight of nandrolone decanoate. The steroid and physiological solution were administered intraperitoneally, with a single injection per week for 4 consecutive weeks. The applied physical effort was swimming (20 minutes daily, 5 days/week, for the 4 weeks of treatment). Serial sections (5 µm) of ovaries were prepared for histological evaluation and follicular score. The weight of ovaries and hypophysis, the number of antral and atretic follicles, and the area of corpus luteum were all affected by the steroids. In the ovaries of the control groups, well-developed corpus luteum was observed. In the treated groups, the cortical stroma was occupied by ovarian interstitial tissue. The females treated with steroids presented estral acyclicity. The use of nandrolone decanoate, whether associated with physical effort or not, affected the morphological pattern of the ovaries.

PURPOSE: to evaluate the effects of the administration of two synthetic steroids in the uterus mo... more PURPOSE: to evaluate the effects of the administration of two synthetic steroids in the uterus morphology and in the reproductive parameters of adult female rats. METHODS: divided into four experimental groups: control (C; physiological solution); treated with nandrolone decanoate (DN; 7.5 mg/kg of body weight); with a testosterone esters compound (T; 7.5 mg/kg); and simultaneously with DN and T (7.5 mg/kg of each steroid), in a single intraperitoneal weekly dose, for eight weeks. Five females of each group were sacrificed and the uterine horns were collected, weighted and prepared for histological and morphometrical evaluation. The remaining rats were mated with normal male rats for reproductive parameters evaluation, composing the groups treated during the pre-gestational period. Another group of 20 female rats were treated during the gestational period (7th-14th days). For data analysis, the Kruskal-Wallis non-parametric variance analysis was used, followed by the test of Dunn or of Student-Newman-Keus (5% significance level). RESULTS: there was a significant body weight increase in the androgenized females (ND: 305±50; T: 280±35; ND+T: 275±30 versus C: 255±22 g; p<0.05). Uterine weight was not affected by the steroidal treatment (ND: 0.6±0.2; T: 0.4±0.04; ND+T: 0.7±0.1 versus C: 0.4±0.09 g). All the androgenized females presented estral acyclicity and endometrium characterized by papilliferous luminal lining, oedematous stroma with hemorrhagic areas and secretory activity. There were changes in the morphometrical thickness parameters of the luminal epithelium, myometrium and perimetrium in the androgenized groups. None of the female rats got pregnant when treated with steroids in the pre-gestational period and the treatment during organogenesis affected negatively the reproductive parameters. CONCLUSIONS: steroidal agents alter the uterine structure and impair fertility and gestational outcome in female rats.
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Papers by Suzana Mesquita