Achyrocline alata potentiates repair of skin full thickness excision in mice.

Plants of the Asteraceae family have been traditionally used as medicinal plants. The species Achyrocline satureioides and Achyrocline alata present anti-inflammatory properties and great chemical similarity. However, no study has been performed to evaluate the influence of these plants on skin wound healing in vivo. Here, we have assessed the effect of these plants extracts on skin wound healing in mice. Mice were randomly arranged into three groups (n = 10), an injury was performed on the dorsal area of the animals, which received the following topical treatment: group 1, control (ointment base); group 2, A. satureioides extract; group 3, A. alata extract. The solution for treatment was prepared as 10% (w/w) concentration. The wound area was measured on days 1, 4, 9, 15 and 17 after treatment and tissues of local lesion were collected on the ninth day for histological analysis. A. alata was more effective since it induced earlier wound closure associated with decreasing initial inflammatory response, faster reepithelialization and collagen remodeling. A. satureioides improved the collagen renovation, but induced slower closure, which may be due to different concentrations of phenolic compounds among the plants here studied. Both plants did not alter the ultrastructural characteristics of cells in the healing process. In conclusion, our findings suggest the potent wound healing capacity of A. alata extracts, as demonstrated by more efficient and faster induction of wound closure. We believe this plant is a potential wound healing treatment for humans and further studies are necessary to assess its clinical practice.

Glycol methacrylate embedding for improved morphological, morphometrical, and immunohistochemical investigations under light microscopy: testes as a model.

Glycol methacrylate (GMA), a water and ethanol miscible plastic resin, is a medium handy to use for light microscopy embedding that has a number of advantages than paraffin embedding. The GMA improves the histological, morphometrical, and immunohistochemical evaluations, mainly due to the accurate assessment of cytological details. This chapter focuses on our experience in the GMA processing and describes in detail the fixation, embedding, and staining methods that we have been using for testes evaluations.

Fenofibrate prevents orotic acid--induced hepatic steatosis in rats.

The experiments performed in this report were designed to investigate the mechanisms involved in the metabolic alterations associated with orotic acid-induced hepatic steatosis and the effect of fenofibrate, a stimulant of peroxisome proliferators-activated receptor alpha (PPARalpha), on these alterations. Male Wistar rats were divided into three experimental groups: 1) fed a balanced diet (C); 2) fed a balanced diet supplemented with 1% orotic acid (OA); 3) fed OA diet containing 100 mg.kg(-1) bw.day(-1) fenofibrate (OA+F), for 9 days. Administration of OA to rats induced significant increase in the hepatic total lipids content, marked microvesicular steatosis and decrease in plasma lipids concentrations compared to control group. Fenofibrate treatment prevented fatty liver induction, caused an additional reduction on plasma lipids concentrations and caused a 40% decrease in the lipogenic rate in adipose tissue. The results also showed a 40% increase in lipoprotein lipase (LPL) activity in adipose tissue from OA treated group and fenofibrate administration induced a 50% decrease in LPL activity. The liver mRNA expression of PPARalpha and ACO (acyl CoA oxidase) were 85% and 68% decreased in OA group when compared to control, respectively. Fenofibrate treatment increased the PPARalpha and ACO expressions whereas the CPT-1 (carnitine palmitoyl transferase-1) expression was not altered. Our results have shown that fenofibrate treatment decreases the hepatic lipid content induced by OA which is mediated by an important increase in fatty acid oxidation consequent to an increase in hepatic mRNA expression of PPARalpha and ACO.

Effects of fenofibrate on lipid metabolism in adipose tissue of rats.

The effect of fenofibrate, a peroxisome proliferator-activated receptor alpha agonist, on body weight gain and on reduction of adipose tissue pads has been ascribed to increased fat catabolism in liver mainly through the induction of target enzymes involved in hepatic lipid metabolism. The aim of this study was to investigate whether peroxisome proliferator-activated receptor alpha activation also affects metabolic pathways in adipose tissue of rats treated with fenofibrate (100 mg/kg body weight) for 9 days. Fenofibrate lowered body weight gain and plasma triglyceride, total cholesterol, and high-density lipoprotein cholesterol but had no influence on food intake and on plasma glucose levels. The activity of lipoprotein lipase of treated animals decreased 50% in epididymal, 29% in retroperitoneal, and was not affected in the mesenteric fat pads. In this study, we show a 34% decrease in epididymal adipose tissue de novo lipogenesis by fenofibrate. The results demonstrate that insulin sensitivity of lipolysis is decreased in fenofibrate-treated rats which resulted in 30% higher rate of glycerol release when compared to the control group. These findings suggest that besides its effects on liver, fenofibrate exerts effects on lipid metabolism in adipose tissue which may contribute to decreasing adiposity.

Development and function of the adult generation of Leydig cells in mice with Sertoli cell-selective or total ablation of the androgen receptor.

It is established that androgens and unidentified Sertoli cell (SC)-derived factors can influence the development of adult Leydig cells (LC) in rodents, but the mechanisms are unclear. We evaluated adult LC development and function in SC-selective androgen receptor (AR) knockout (SCARKO) and complete AR knockout (ARKO) mice. In controls, LC number increased 26-fold and LC size increased by approximately 2-fold between 12 and 140 d of age. LC number in SCARKOs was normal on d 12, but was reduced by more than 40% at later ages, although LC were larger and contained more lipid droplets and mitochondria than control LC by adulthood. ARKO LC number was reduced by up to 83% at all ages compared with controls, and LC size did not increase beyond d 12. Serum LH and testosterone levels and seminal vesicle weights were comparable in adult SCARKOs and controls, whereas LH levels were elevated 8-fold in ARKOs, although testosterone levels appeared normal. Immunohistochemistry and quantitative PCR for LC-specific markers indicated steroidogenic function per LC was probably increased in SCARKOs and reduced in ARKOs. In SCARKOs, insulin-like factor-3 and estrogen sulfotransferase (EST) mRNA expression were unchanged and increased 3-fold, respectively, compared with controls, whereas the expression of both was reduced more than 90% in ARKOs. Changes in EST expression, coupled with reduced platelet-derived growth factor-A expression, are potential causes of altered LC number and function in SCARKOs. These results show that loss of androgen action on SC has major consequences for LC development, and this could be mediated indirectly via platelet-derived growth factor-A and/or estrogens/EST.

In vitro activity of labdane diterpene from Alomia myriadenia (Asteraceae): immunosuppression via induction of apoptosis in monocytes.

A screening program in Brazilian flora was carried out to detect the presence of immunosuppressive compounds by using the in vitro phytohemagglutinin A (PHA)-induced human peripheral blood mononuclear cell (PBMC) proliferation assay. In this screening, we isolated from Alomia myriadenia Schultz-Bip. ex. Baker (Asteraceae), a labdane-type diterpene named myriadenolide. Incubation of human PBMC with this compound reduced significantly the percentage of CD14(+) cells, but it has no effect on the relative amount of CD3(+)CD4(-)CD8(+) and CD3(+)CD4(+)CD8(-) T lymphocyte subpopulations. Neither viability nor proliferative competence of T lymphocytes was significantly affected by myriadenolide. The toxic effect on monocytes (CD14(+) cells) may explain the inhibitory effect observed on PHA-induced lymphocyte proliferation. The cytotoxic effect of myriadenolide on monocytes was determined by measuring the percentage of hypodiploid nuclei content by propidium iodide staining, electron microscopy and simultaneous detection of CD14 and annexin V binding by flow cytometry. The results showed that myriadenolide induces a dose-dependent apoptosis in monocytes and thus explain the immunosuppressive effect observed.

Biologia reprodutiva de machos Bolomys lasiurus Lund, 1841 (Rodentia, Cricetidae). I. Morfologia da espermatogênese e ciclo do epitélio seminífero / Reproductive biology of males Bolomys lasiurus Lund, 1841 (Rodentia, Cricetidae). I. Morphology of spermatogenesis and seminiferous epithelium

Estudaram-se aspectos morfológicos e cinéticos de espermatogênese de roedores silvestres da espécie Bolomys lasiurus Lund, 1841, capturados no município de Belo Horizonte (Lat. 19-52'S; Long. 43-59'W), Zona Metalúrgica de Minas Gerais, Brasil. Identificaram-se, pelo método da morfologia tubular, 8 estádios do ciclo do epitélio seminífero, os quais apresentaram as seguintes freqüências: estádio 1 = 13,8 ñ 1,3%; estádio 2 = 7,2 ñ 0,9%; estádio 3 = 15,2 ñ 1,2%; estádio 4 = 3,7 ñ 0,9%; estádio 5 = 15,7 ñ 2,3%; estádio 6 = 10,6 ñ 1,9%; estádio 7 = 11,1 ñ 2,4% e estádio 8 = 22,0 ñ 1,7%. Os estádios pré-divisionais (1 a 3) e os pós-divisionais (5 a 8) perfizeram 35,0% e 50,0% do ciclo, respectivamente. Os dados obtidos indicaram que a espermatogênese de Bolomys lasiurus assemelha-se, em suas características morfológicas e cinéticas básicas, à de outros roedores, especialmente cricetídeos silvestres de áreas temperadas