Abstract-We demonstrated recently that chronic administration of aldosterone to rats induces glomerular mesangial injury and activates mitogen-activated protein kinases including extracellular signal-regulated kinases 1/2 (ERK1/2). We also observed that the aldosterone-induced mesangial injury and ERK1/2 activation were prevented by treatment with a selective mineralocorticoid receptor (MR) antagonist, eplerenone, suggesting that the glomerular mesangium is a potential target for injuries induced by aldosterone via activation of MR. In the present study, we investigated whether MR is expressed in cultured rat mesangial cells (RMCs) and involved in aldosterone-induced RMC injury. MR expression and localization were evaluated by Western blotting analysis and fluorolabeling methods. Cell proliferation and micromechanical properties were determined by [ 3 H]-thymidine uptake measurements and a nanoindentation technique using an atomic force microscope cantilever, respectively. ERK1/2 activity was measured by Western blotting analysis with an anti-phospho-ERK1/2 antibody. Protein expression and immunostaining revealed that MR was abundant in the cytoplasm of RMCs. Aldosterone (1 to 100 nmol/L) dose-dependently activated ERK1/2 in RMCs with a peak at 10 minutes. Pretreatment with eplerenone (10 mol/L) significantly attenuated aldosterone-induced ERK1/2 phosphorylation. Aldosterone (100 nmol/L) treatment for 30 hours increased Key Words: mineralocorticoids Ⅲ aldosterone T he utility of mineralocorticoid receptor (MR) antagonists in renal injury has been suggested in preclinical and clinical studies. 1-12 MR blockade had no effect on systemic blood pressure but markedly ameliorated glomerular injury in stroke-prone spontaneously hypertensive rats 3 and rats treated with angiotensin II (Ang II) and an NO synthase inhibitor, 4 cyclosporine A 5 or radiation. 6 In patients with chronic renal failure 7 and early diabetic nephropathy, 8 addition of a nonselective MR antagonist, spironolactone, to angiotensinconverting enzyme (ACE) inhibitors had no hemodynamic effects but markedly reduced the urinary protein excretion rate (U protein V). For hypertensive patients, it has also been indicated that monotherapy with spironolactone 9 or a selective MR antagonist, eplerenone, 10 is more effective than ACE inhibitors in reducing U protein V. Furthermore, White et al 11 showed that in hypertensive patients, eplerenone has a similar blood pressure-lowering effect to a calcium antagonist, amlodipine, but reduced the urinary albumin-to-creatinine ratio to a greater extent than amlodipine. Thus, these observations support the notion that MR blockade has renoprotective effects through mechanisms that cannot be simply explained by hemodynamic changes.We demonstrated recently that chronic administration of aldosterone to rats induced glomerular injury characterized by mesangial matrix expansion and cell overgrowth. 12 We also observed that the aldosterone-induced glomerular injury was prevented by treatment with eplerenone. These results in...

The interaction between monocytes and endothelial cells is considered to play a major role in the early stage of atherosclerosis, and the involved endothelial cell micromechanics may provide us with important aspects of atherogenesis. In the present study, we evaluated (i) the endothelial cell-to-cell and cell-to-substrate gaps with the electric cell-substrate impedance sensing system, which can detect the nanometer order changes of cell-to-cell and cell-tosubstrate distances separately, and (ii) the endothelial cell micromechanical properties with an atomic force microscope after application of monocytes to endothelial cells. Application of monocytic THP-1 cells to IL-1␤-stimulated human umbilical vein endothelial cells immediately decreased the electrical resistance of the endothelial cell-to-substrate (increase of the cell-to-substrate gap), whereas the endothelial cell-to-cell resistance (cell-to-cell gap) did not change. The elastic modulus of the endothelial cells decreased after 2-h monocyte application, indicating an increase of endothelial cell deformability. In conclusion, the interaction of the monocytes to the endothelial cells reduced the adhesiveness to the substrate and increased the deformability of endothelial cells. These changes in the adhesiveness and the deformability may facilitate migration of monocytes, a key process of atherogenesis in the later stage.A t the early stage of atherosclerosis, an aggregation of lipid-rich macrophages that were derived from monocytes was observed in the intima (1). Adhesion of monocytes to the arterial endothelial cells and their migration into the arterial intima are the earliest key events in atherogenesis (1). Previous studies demonstrated that leukocytes could migrate throughout the endothelial monolayer via not only paracellular but also transcellular pathways in vivo and in vitro (2-5). The endothelial cell micromechanics that are involved in endothelial cell micromotion and the mechanical properties of endothelial cells may be key factors in these processes. Earlier studies reported the importance of adhesion molecules in the adhesion and migration of monocytes to endothelial cells (6, 7). We previously demonstrated that the adhesion of monocytes to human umbilical vein endothelial cells (HUVEC) induces the decrease in the amount of focal adhesion kinase (p125 FAK ) with reduction of the density of F-actin stress fibers in HUVEC (8). These results suggest that the adhesion of monocytes induces changes of the adhesiveness of endothelial cells to the substrate and the mechanical properties of endothelial cells. However, the accompanying micromechanics and micromotion of endothelial cells were little understood.For the micromotion measurement of the cultured cells, Giaever and Keese (9) developed a morphological biosensor, the electric cell-substrate impedance sensing (ECIS) system. The advantage of this system is that quantitative estimation of cell-to-cell and cell-to-substrate distances can be performed separately and in real time. Atomic force micros...

Fruits and seeds of melinjo (Gnetum gnemon L.) are resveratrol derivative-rich materials. Pharmacokinetics of resveratrol derivatives in healthy volunteers after oral administration of 1000 mg of melinjo seed extract (MSE) powder were assessed and compared with those after oral dosing of trans-resveratrol (tRV) powder containing 4.8 mg of tRV only, equivalent to the content in 1000 mg MSE powder. Plasma tRV concentrations with enzymatic hydrolysis were maintained over 24 h, with a tmax of 12 h and a mean residence time (MRT) of 14 h, 5 and 2 times higher than those for tRV powder intake, respectively. Gnetin C, a resveratrol dimer, with hydrolysis was maintained in plasma for >96 h with a 36 h MRT. With repeated doses once daily for 28 days, plasma tRV and gnetin C concentrations with hydrolysis were in good agreement with the theoretical curves. MSE powder was well tolerated up to the oral dosing of 5000 mg with no serious adverse events.

Aging is associated with motor disorders that decrease the quality of life (QOL). Royal jelly (RJ), used as a dietary supplement, has shown various health benefits and, therefore, it has the potential to improve the QOL during aging. We have previously developed protease enzyme-treated RJ to avoid the anaphylactic response induced by RJ supplementation. However, the effects of a lifelong treatment with RJ on normal aging have not been fully clarified. In this study, we investigated the effects of enzyme-untreated RJ (NRJ) and enzyme-treated RJ (ERJ) on the aging process focusing on motor functions, by using a genetically heterogeneous (HET) mouse model experimentally endowed with genetic diversity. We performed four different physical performance tests (grip strength, wire hang, horizontal bar, and rotarod). We showed that the age-related impairment of the motor functions was significantly delayed in RJ-treated mice. Both NRJ and ERJ were similarly effective against these types of aging-associated declines. Histological analyses revealed that the RJ treatment affected the muscle fiber size at an advanced age. We also demonstrated that age-related changes in muscle satellite cell markers and catabolic genes were affected in RJ-treated mice. These results suggest that non-protein components of RJ improved the motor function in aging mice. These findings indicate that RJ has the potential to change the QOL during aging by regulating the motor function.

Free fatty acids (FFA) are known to uncouple oxidative phosphorylation in mitochondria. However, their mechanism of action has not been elucidated as yet. In this study we have investigated in detail the patterns of uncoupling by the FFA oleate and palmitate in rat liver mitochondria and submitochondrial particles. The patterns of uncoupling by FFA were compared to uncoupling induced by the ionophores valinomycin (in the presence of K+) and gramicidin (in the presence of Na+) and the proton translocator carbonyl cyanide m-chlorophenylhydrazone (CCCP). The most striking difference in the pattern of uncoupling relates to the effect on the proton electrochemical potential gradient, delta mu H. Uncoupling by ionophores, particularly valinomycin, is associated with and most likely caused by a major reduction of delta mu H. In contrast, uncoupling by FFA is not associated with a significant reduction of delta mu H, indicating another mechanism of uncoupling. We suggest the use of the term decouplers for uncoupling agents such as FFA and general anesthetics that do not collapse the delta mu H [Rottenberg, H. (1983) Proc. Natl. Acad. Sci. U.S.A. 80, 3313-3317]. The protonophore CCCP and to some extent the ionophore gramicidin indicate a mixed mode of uncoupling since their effect on delta mu H is moderate when compared to that of valinomycin. Another distinguishing feature of uncouplers that collapse the delta mu H is their ability to stimulate ADP-stimulated respiration (state 3) further. Decouplers such as FFA and general anesthetics do not stimulate state 3 respiration.(ABSTRACT TRUNCATED AT 250 WORDS)

This is the first report of microbiota analysis of royal jelly and the immune efficacy of Lact. kunkeei from honeybee products in humans.

No abstract

No abstract