Role of estrogen and progesterone in the modulation of CNG-A1 and Na/K+-ATPase expression in the renal cortex.

The steroid hormones, estrogen and progesterone, are involved mainly in the control of female reproductive functions. Among other effects, estrogen and progesterone can modulate Na(+) reabsorption along the nephron altering the body's hydroelectrolyte balance. In this work, we analyzed the expression of cyclic nucleotide-gated channel A1 (CNG-A1) and α1 Na(+)/K(+)-ATPase subunit in the renal cortex and medulla of female ovariectomized rats and female ovariectomized rats subjected to 10 days of 17ß-estradiol benzoate (2.0 µg/kg body weight) and progesterone (1.7 mg/kg body weight) replacement. Na(+)/K(+) ATPase activity was also measured. Immunofluorescence localization of CNG-A1 in the cortex and medulla was performed in control animals. We observed that CNG-A1 is localized at the basolateral membrane of proximal and distal tubules. Female ovariectomized rats showed low expression of CNG-A1 and low expression and activity of Na(+)/K(+) ATPase in the renal cortex. When female ovariectomized rats were subjected to 17ß-estradiol benzoate replacement, normalization of CNG-A1 expression and Na(+)/K(+) ATPase expression and activity was observed. The replacement of progesterone was not able to recover CNG-A1 expression and Na(+)/K(+) ATPase expression at the control level. Only the activity of Na(+)/K(+) ATPase was able to be recovered at control levels in animals subjected to progesterone replacement. No changes in expression and activity were observed in the renal medulla. The expression of CNG-A1 is higher in cortex compared to medulla. In this work, we observed that estrogen and progesterone act in renal tissues modulating CNG-A1 and Na(+)/K(+) ATPase and these effects could be important in Na(+) and water balance.

Extracellular matrix secreted by reactive stroma is a main inducer of pro-tumorigenic features on LNCaP prostate cancer cells.

Tumor microenvironment modifications are related to the generation of reactive stroma and to critical events in cancer progression, such as proliferation, migration and apoptosis. In order to clarify these cellular interactions mediated by reactive stroma, we investigated the effects of cell-cell contacts, and the influence of soluble factors and extracellular matrix (ECM) secreted by Benign Prostate Hyperplasia (BPH) reactive stroma over LNCaP prostate tumor cells. Using in vitro functional assays, we demonstrated that ECM strongly stimulated LNCaP cell proliferation and migration, while inhibiting apoptosis, and inducing a deregulated expression pattern of several genes related to prostate cancer (PCa) progression. Conversely, reactive stromal cells per se and their secreted conditioned medium partially modulated these pro-tumorigenic events. These data indicate that secreted ECM in reactive stroma microenvironment contains key molecules that positively modulate important cancer hallmarks.

Effects of a nanocomposite containing Orbignya speciosa lipophilic extract on Benign Prostatic Hyperplasia.

ETHNOPHARMACOLOGICAL RELEVANCE: Lower urinary tract symptoms (LUTS) are a common complaint among aging men and are usually caused by Benign Prostatic Hyperplasia (BPH). A number of medical treatments for LUTS/BPH exist, such as α-blockers, 5α-reductase inhibitors, phytotherapeutical drugs and combination therapies. Babassu is the common name of a Brazilian native palm tree called Orbignya speciosa, whose kernels are commonly used (eaten entirely or as a grounded powder), in parts of Brazil for the treatment of urinary disorders. This study investigates the effects of Orbignya speciosa nanoparticle extract, a newly developed phytotherapic formulation derived from the kernels of babassu, in the treatment of BPH. MATERIALS AND METHODS: Orbignya speciosa extract was obtained from the kernels, a nanoparticulate system was developed and acute toxicity test was performed. BPH primary stromal cell and tissue cultures were established and treated with 300µg/mL Orbignya speciosa nanoparticle (NanoOse) extract in order to evaluate its effects on apoptosis induction, cytotoxicity, cell morphology and proliferation. RESULTS: Our results indicated that NanoOSE shows no toxicity in animals and acts incisively by promoting morphological cell changes, reducing cell proliferation as well as inducing necrosis/apoptosis on BPH cells and tissues. CONCLUSIONS: This study provided the first report of the successful use of NanoOSE on BPH treatment which corroborates with the popular use of the kernels of this plant. The results also suggest the potential of NanoOSE as a candidate new phytotherapeutic agent on the management of BPH.

Bone marrow subendosteal microenvironment harbours functionally distinct haemosupportive stromal cell populations.

In adult animals, bone marrow is the major site of blood cell production, which is controlled by interactions between the local stroma and blood cell progenitors. The endosteal/subendosteal environment comprises bone-lining and adjacent reticular cells and sustains haemopoietic stem cell (HSC) self-renewal, proliferation and differentiation. We have questioned the specific role of each of these stroma cells in controlling HSC fate. We have isolated two distinct stroma-cell populations containing subendosteal reticulocytes (F-RET) and osteoblasts (F-OST) from periosteum-free fragments of murine femurs by a two-step collagenase-digestion procedure. Both populations produce similar extracellular matrix (collagen I, laminin, fibronectin, decorin), except for collagen IV, which is low in F-OST. They also express osteogenic markers: osteopontin, osteonectin, bone sialoprotein and alkaline phosphatase (ALP). The quantity and activity of ALP are however higher in F-OST. When co-cultured with bone marrow mononuclear cells or lineage-negative haemopoietic progenitors, F-OST stroma induces low proliferation and high maintenance of early haemopoietic progenitors, whereas F-RET stroma induces high short-term proliferation and differentiation. Analysis by reverse transcription/polymerase chain reaction has revealed higher levels of Jagged-1 expression by F-OST cells than by the F-RET population. Thus, two adjacent stroma cells (subendosteal and endosteal) play distinct roles in controlling the stem-cell capacity and fate of HSC and probably contribute distinctly to HSC niche formation.

A continuous lineage of rat adenohypophysis stromal cells: characterisation and effects on GH(3)B(6) prolactin-secreting cell behaviour.

Although some studies have shown a possible modulation of the stroma on the hormonal secretion, it is not clear as to what are the requirements for these cellular interactions. In the present work, a homogeneous and continuous lineage of rat adenohypophysis stromal cells (APS9 cells) obtained from rat adenohypophysis primary culture was established. Using immunocytochemical methods and electron microscopy, we have characterised APS9 cells as elongated fibroblastoid-like cells with intercellular contacts, expressing alpha-smooth muscle actin, type IV collagen and laminin. By biochemical procedures, higher amounts of chondroitin sulphate and heparan sulphate were found in the pericellular and extracellular compartments of APS9 cell culture. In order to evaluate the possible effects of APS9 cell on GH(3)B(6) prolactin-secreting cell survival and/or proliferation, we established co-culture and proliferation assays. When GH(3)B(6) cells were cultivated on APS9 cell substrate, they displayed an organisation of many cellular cords strongly attached and covering all the stromal cell area, establishing punctual interactions or extensive surface associations between adjacent cells. Prolactin immunoreactivity appeared to be more scattered throughout the cytoplasm and accumulated in its periphery. When plated on glass coverslips, on newborn rat skin fibroblasts, on murine haematopoietic bone marrow stroma cell line or on murine foetal liver stroma cell line, GH(3)B(6) cells changed their organisation and presented a decrease in cell number and adherence to the substrate. Our results showed that the APS9 cell/GH(3)B(6) cell interactions favour cell growth and probably PRL secretion, and raises questions about the specificity of different organs and/or animal species stromas on the hormone secretion.