Summary:been strengthened by several observations showing that growth factors (such as G-CSF, GM-CSF, IL-3 and SCF) modulate the expression or function of several cytoadhesive Transplantation of growth factor-mobilized peripheral blood progenitor cells (PBPC) is widely used in the molecules on the surface of hematopoietic progenitor cells. 8,9 In addition, cytokines produce profound morphotreatment of several neoplastic diseases. While in PBPC harvests the presence of several accessory immune and logical and immunohistochemical changes in marrow stroma and in the contiguous extracellular matrix. 10,11 tumor cells has been documented, that of stromal cells has not been reported. In the present study, we investiThese results suggest that marrow stroma should not be impervious to the effect of growth factors during PBPC gated for the presence of stromal cells in growth factormobilized PBPC harvests from breast cancer patients.mobilization procedures and raise the question of whether stromal cells are released from the marrow and conseLow-density cells from PBCP harvests in culture gave rise to an adherent layer containing fibroblast-like and quently are present in cytokine-mobilized PBPC harvests.In the present study, we monitored the presence of stromal large flat round cells. These cells express positive immunofluorescence staining for collagen I, collagen III, fibcells in growth factor-mobilized PBPC harvests from breast cancer patients. For this purpose, we used a two-step proronectin, VCAM-1 (CD106), ICAM-1 (CD54) and mesenchymal antigens recognized by monoclonal cedure which includes: (1)

There are disparate observations on central and peripheral effects of leptin, but several studies consistently support its role as a link between fat and bone. Bone marrow stroma contains mesenchymal stem cells (MSCs), which differentiate into osteoblasts and adipocytes, among others. In this study we assessed the expression of leptin receptors protein in MSCs from control and osteoporotic postmenopausal donors and their change during osteogenic and adipogenic differentiation. Also, we assessed the effects of leptin on osteogenic and adipogenic differentiation of these cells. We demonstrated high affinity leptin binding (KD = 0.36 +/- 0.02 nM) in both types of cells. Binding was very low under basal, but increased significantly (2-3 times) through osteogenic and adipogenic differentiation. Osteoporotic MSCs showed lower leptin binding capacity than control cells at an early osteogenic and adipogenic differentiation time, which could restrict cell sensitivity to the protective action of leptin. In this regard, we observed that leptin significantly inhibited adipocyte differentiation in control but not in osteoporotic MSCs, while it exerted a low stimulatory effect on calcium deposition (10%-20%) in both types of MSCs cells. In summary, we report the presence of high affinity leptin receptors on control and osteoporotic MSCs, which were modified distinctly by osteogenic and adipogenic stimulation and a direct and distinct effect of leptin on both type of cells.

Osteoporosis is characterized by low bone mass, microarchitectural deterioration of bone tissue leading to increased bone fragility, and a resulting susceptibility to fractures. Distinctive environmental bone marrow conditions appear to support the development and maintenance of the unbalance between bone resorption and bone formation; these complex bone marrow circumstances would be reflected in the fluid surrounding bone marrow cells. The content of regulatory molecules in the extracellular fluid from the human bone marrow is practically unknown. Since the content of cytokines such as adiponectin, leptin, osteoprogeterin (OPG), soluble receptor activator of nuclear factor kB ligand (s-RANKL), tumor necrosis factor a, and interleukin 6 (IL-6) may elicit conditions promoting or sustaining osteoporosis, in this work we compared the concentrations of the above-mentioned cytokines and also the level of the soluble receptors for both IL-6 and leptin in the extracellular fluid from the bone marrow of nonosteoporotic and osteoporotic human donors. A supernatant fluid (bone marrow supernatant fluid [BMSF]) was obtained after spinning the aspirated bone marrow samples; donors were classified as nonosteoporotic or osteoporotic after dual-energy X-ray absorptiometry (DXA) measuring. Specific commercially available kits were used for all measurements. The cytokines' concentration in BMSF showed differently among nonosteoporotic and osteoporotic women; this last group was characterized by higher content of proinflammatory and adipogenic cytokines. Also, osteoporotic BMSF differentiated by decreased leptin bioavailability, suggesting that insufficient leptin action may distinguish the osteoporotic bone marrow. ß

. No hubo cambios significativos del peso ni del perfil lipídico, a excepción de los triglicéridos, que disminuyeron (P = 0,04). Conclusiones. El nivel primario de atención es ideal para ejecutar programas educativos sobre el tratamiento y la detección temprana de la diabetes dirigidos a los pacientes, sus familiares y el personal sanitario. Se logró incorporar el programa educativo a la planificación anual del área de salud.Intervención educativa, salud pública, diabetes, educación sobre la diabetes, participación comunitaria. RESUMENEl reconocimiento de la diabetes de tipo 2 como una enfermedad crónica que afecta a millones de personas en el mundo ha motivado la búsqueda de diversos ámbitos de atención de salud, enfoques y metodologías que favorezcan un acercamiento real al problema, principalmente en relación con los conocimientos, las percepciones, las actitudes, los temores y las prácticas de los pacientes en el contexto familiar y comunal.Por ello, para responder a las necesidades educativas y a los problemas de las comunidades, se están incorporando las teorías y modelos de las ciencias sociales a los programas de salud del primer nivel de atención, con

Osteoblasts, the cells responsible for bone formation, derive from mesenchymal stem cells (MSCs) in bone marrow. To acquire a new cell phenotype, uncommitted MSCs must undergo several proliferation and differentiation changes. Although, it is known that extracellular signal-regulated protein kinases (ERKs) mitogen-activated protein (MAP) kinase pathway signaling is involved in the proliferation and differentiation processes, the role of ERKs in osteogenic differentiation it is controversial, at present. In addition, the function that ERK could play in MSCs derived from osteoporotic patients it is not well documented. In this study, we analyze whether previously observed differences in the dynamic response of MSCs from normal and osteoporotic postmenopausal women can be explained by changes in the activation of this signal transduction pathway. Levels of ERK phosphorylation and their correlation with osteogenic differentiation were evaluated in cultures of MSCs derived from osteoporotic postmenopausal women and "healthy" controls. The results show that, under basal conditions, MSCs derived from osteoporotic donors show a level of ERK phosphorylation 2.5 times higher than MSCs derived from control donors. The addition of the osteogenic stimulus only slightly increases the p-ERK level in cells derived from osteoporotic donors, and is higher in cells derived from control women. Important differences in the ability of PD98059 to inhibit phosphorylation of ERK in both types of cells were also observed, as well as the effect that this inhibition produced on calcium deposition. We conclude that the MAP kinase pathway signaling is differentially activated in MSCs derived from osteoporotic postmenopausal women. The high p-ERK levels in MSC derived from osteoporotic donors could determine the unresponsiveness of these cells to the osteogenic differentiation stimulus.

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Human mesenchymal stem cells (hMSCs) are multipotent cells present in bone marrow, which differentiate into osteoblasts and adipocytes, among other lineages. Oestrogens play a critical role in bone metabolism; its action may affect the adipocyte to osteoblast ratio in the bone marrow. In hMSCs, oestrogens are synthesized from C19 steroids by the enzyme aromatase cytochrome P450. In this study, we assessed whether aromatase enzymatic activity varied through early osteogenic (OS) and adipogenic (AD) differentiation. Also, we studied the effect of leptin and 1,25 dihydroxyvitamin D 3 (1,25(OH) 2 D 3 ) on aromatase cell activity. Finally, we analysed whether conditions that modify oestrogen generation by cells affected hMSCs differentiation. For these purposes, hMSCs derived from postmenopausal women (65-86 years old) were cultured under basal, OS or AD conditions, in the presence or the absence of leptin and 1,25(OH) 2 D 3 . Aromatase activity was measured by the tritiated water release assay and by direct measurement of steroids synthesized from 3 H-labelled androstenedione or testosterone. Our results showed that different OS and AD patterns of aromatase activity developed during the first period of differentiation (up to 7 days). A massive and sharp surge of aromatase activity at 24 h characterized early OS differentiation, while increased but constant aromatase activity was increased through adipogenesis. Both leptin and vitamin D increased aromatase activity during osteogenesis, but not during adipogenesis; finally, we showed that favourable aromatase substrates concentration restrained MSCs adipogenesis but improved osteogenesis. Thus, it could be inferred that a high and early increase of local oestrogen concentration in hMSCs affects their commitment either restraining AD or facilitating OS differentiation, or both.

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