Kallikrein-kinin system and oxidative stress in cisplatin-induced ovarian toxicity.

Kallikrein-kinin system (KKS) is involved in vascular reactivity and inflammatory response to cytotoxic drugs. Since cisplatin is a widely used chemotherapy and its cytotoxic mechanism can trigger inflammation and oxidative damage, in this work we evaluated the role of KKS in an animal model of cisplatin-induced ovarian toxicity. Biomarkers of ovarian stem cells, activity of KKS, inflammation and oxidative damage were measured in ovarian tissue of C57BL/6 female mice treated with vehicle or cisplatin (2.5 mg/kg). Cisplatin group presented greater number of atretic follicles, and lower numbers of antral and total viable follicles. Ki67, DDX4 and OCT-4 markers were similar between groups. Cisplatin triggered plasma and ovarian tissue kallikrein generation; and increased expression of bradykinin receptors B1 and B2. Neutrophil and macrophage infiltration markers increased. Superoxide anion generation also increased, while reduced glutathione levels decreased. These results suggest that KKS is activated and contributes to ovarian injury during cisplatin treatment.

Electrophysiological Responses to Different Follicle-Stimulating Hormone Isoforms on Human Cumulus Oophorus Cells: Preliminary Results.

OBJECTIVE: The aim of the present study was to provide a better understanding of the specific action of two follicle-stimulating hormone (FSH) isoforms (ß-follitropin and sheep FSH) on the membrane potential of human cumulus cells. METHODS: Electrophysiological data were associated with the characteristics of the patient, such as age and cause of infertility. The membrane potential of cumulus cells was recorded with borosilicate microelectrodes filled with KCl (3 M) with tip resistance of 15 to 25 MΩ. Sheep FSH and ß-follitropin were topically administered onto the cells after stabilization of the resting potential for at least 5 minutes. RESULTS: In cumulus cells, the mean resting membrane potential was - 34.02 ± 2.04 mV (n = 14). The mean membrane resistance was 16.5 ± 1.8 MΩ (n = 14). Sheep FSH (4 mUI/mL) and ß-follitropin (4 mUI/mL) produced depolarization in the membrane potential 180 and 120 seconds after the administration of the hormone, respectively. CONCLUSION: Both FSH isoforms induced similar depolarization patterns, but ß-follitropin presented a faster response. A better understanding of the differences of the effects of FSH isoforms on cell membrane potential shall contribute to improve the use of gonadotrophins in fertility treatments.

OBJETIVO: O objetivo do presente estudo foi fornecer uma melhor compreensão da ação específica de duas isoformas de hormônio folículo estimulante (FSH, sigla em inglês) (ß-folitropina e FSH ovino) no potencial de membrana de células do cumulus oophorus humanas. MéTODOS: Dados eletrofisiológicos foram associados às características da paciente, como idade e causa da infertilidade. O potencial de membrana das células do cumulus foi registrado com microeletrodos de borossilicato preenchidos com KCl (3 M) com uma resistência de 15 a 25 MΩ. O FSH ovino e a ß-folitropina foram administrados topicamente nas células após a estabilização do potencial de repouso durante pelo menos 5 minutos. RESULTADOS: Nas células do cumulus, o potencial médio de membrana em repouso foi de -34,02 ± 2,04 mV (n = 14). A resistência média da membrana foi de 16,5 ± 1,8 MΩ (n = 14). O FSH ovino (4 mUI/mL) e a ß-folitropina (4 mUI/mL) produziram despolarização no potencial de membrana 180 e 120 segundos após a aplicação do hormônio, respectivamente. CONCLUSãO: Ambas as isoformas de FSH induzem padrões de despolarização semelhantes, mas a ß-folitropina apresentou uma resposta mais rápida. Uma melhor compreensão das diferenças dos efeitos das isoformas do FSH no potencial da membrana celular contribuirá para aprimorar o uso das gonadotrofinas no estímulo ovariano controlado e em protocolos de maturação oocitária in vitro.

Adipose-derived stem cells improve full-thickness skin grafts in a rat model.

To investigate the effects of heterologous adipose-derived stem cells (ADSCs) on autologous full-thickness skin grafts, we designed a first-intention healing model using Wistar rats. We harvested and sutured two full-thickness skin grafts in the dorsal recipient beds of 15 rats, randomized into three groups. In the treatment group, 1 × 106 ADSCs resuspended in saline solution (200 µL) were administered subcutaneously to the skin graft. The control group received only saline solution subcutaneously, whereas the negative control group did not receive any treatment. Compressive dressings were maintained until postoperative day 5. The grafts were assessed by two observers, who checked for the presence of epidermolysis on day 14. Planimetry showed the relative areas of normal skin, redness, ulceration, and contraction. Graft samples were obtained on day 14 and stained with hematoxylin and eosin and Masson's trichrome. Epidermal analysis evaluated thickening, keratosis, acanthosis, hydropic degeneration, and inflammatory infiltrate. Dermal evaluation investigated the absence of hair follicles, granulation tissue formation, presence of inflammatory infiltrate, and collagen deposition. Immunohistochemistry was performed for dermal anti-VEGF and epidermal anti-Ki-67 staining. The ADSC group presented better macroscopic aspects, lower incidence of epidermolysis, and less loss of hair follicles. In addition, the ADSC group presented the lowest frequency of histopathological changes in the dermis and epidermis, as well as the largest subcutaneous and granulation tissue VEGF averages and the weakest Ki-67 staining of the epidermal basal layer. Subcutaneous administration of ADSCs may improve the integration of skin grafts, reducing the deleterious effects of ischemia and reperfusion injury.