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Tissue-hardening effect and health-hazard issue of formaldehyde (FA) have long been a great disadvantage of this conventional fixative in anatomical research. We recently developed a FA-free embalming method for cadavers which utilizes N-vinyl-2-pyrrolidone (NVP) and enables assessment of motion kinetics by maintaining the softness of embalmed tissue. By assessing the feasibility of NVP-embalmed tissue to mimic vocalization, this study aimed to prove the potential of embalmed cadavers, which have previously been used only for the understanding of anatomical morphology, for the assessment of precise motion physiology in the human body. Ten cadavers embalmed in NVP (n = 6) and FA (n = 4) were incorporated in this study. Excised larynges underwent experimental phonation to mimic vocalization with fast and pliable vibration of vocal folds. High-speed digital imaging was utilized for the assessment of vocal fold vibration. Furthermore, acoustic analysis of the voiced sound, and reproducibility examination were also performed. Regular vocal fold vibrations successfully produced voiced sounds during experimental phonation using NVP-embalmed larynges. The vibratory frequency, vibration amplitude, and stretch rate of the vocal folds were comparable to those of living humans. Six months after the first experiment, the vocal parameters were reproduced, to suggest the long-term preservation potential of our NVP-embalming technique. On the other hand, neither voiced sound nor vocal fold vibration were observed in FA-embalmed larynges. This novel embalming technique could pioneer the next era to utilize embalmed cadavers for the examination of motion physiology in the human body.

We developed a novel technology using the photoacoustic effect that improve needle tip visibility. We evaluated whether this technology improves needle tip visibility when performing a deep peripheral nerve block in a cadaver model. A photoacoustic needle was developed using a conventional echogenic needle with an intraluminal optical fiber. A pulsed laser sends light from a source through the fiber, which is converted to ultrasound at the needle tip using the photoacoustic effect. A nerve block expert performed deep nerve blocks using the photoacoustic needle and the ultrasound views recorded, with or without photoacoustic ultrasound at the needle tip. Needle tip visibility was evaluated by questionnaire (Likert scale 1: very poor, 5: very good) completed by anesthesiologists evaluating recorded images. The score was presented as median [first quartile, third quartile]. Statistical analysis was performed using the Wilcoxon matched-pairs signed rank test. The scores of needle tip visibility with photoacoustic ultrasound from the needle tip (4.3 [4.0, 4.5]) was significantly higher than that without photoacoustic ultrasound (3.5 [3.2, 3.8]) (p Clinical trial number University Hospital Medical Information Network Center Clinical Trials Registration System (UMIN000036974).

The traditional apprenticeship approach to surgical skill education for young surgeons has drastically changed to more systematic surgical training using cadavers. Cadavers fixed with formalin are not suitable for surgical training because of their associated health hazards and overhardening. Recently, we established a formalin-free soft preservation method for human cadavers using N-vinyl-2-pyrrolidone. Since 2012, 61 cadavers have been embalmed with pyrrolidone in our institution. Tissues of pyrrolidone-embalmed cadavers are soft and pliable, and their bodies can be preserved for as long as 37 months without any signs of corruption. In this review, we introduce our recent attempts to apply pyrrolidone-embalmed cadavers in surgical and medical procedure training, including endotracheal intubation, motion physiology of the vocal folds, laparoscopic surgery, endoscopic skull base surgery, and development of novel medical devices. Future research perspectives on pyrrolidone embalming are discussed.

The demand for cadavers for clinical skills training is increasing. However, conventional formalin-fixed bodies are often unsuitable for surgical training because the tissues become too hard. We recently developed a new formalin-free embalming method with N-vinyl-2-pyrrolidone (pyrrolidone) that has excellent fixative, disinfectant, and preservative properties, while still keeping tissues soft and pliable. In the study reported here we investigated the feasibility of laparoscopic manipulation using pyrrolidone-fixed cadavers. Donated cadavers were embalmed either with pyrrolidone (n = 7) or with formalin-containing fixative (n = 3). A laparoscopic 12-mm trocar was inserted into the umbilical region, and CO2 gas was insufflated. Intra-abdominal structures were observed with an endoscopic camera. In the pyrrolidone-embalmed cadavers, the abdomen remained soft and depressed. In addition, CO2 injection resulted in a marked expansion of the abdominal cavity, and it was possible to move the laparoscope freely in all directions. Clear endoscopic images of the abdominal viscera were obtained. The gallbladder and rectum were identified by grasping the surrounding organs with forceps. By contrast, in the formalin-fixed bodies, the abdominal wall was rigid, and it was difficult to move the laparoscope in the peritoneal space and observe structures in detail. The amount of CO2 and changes in abdominal diameter and circumference in response to CO2 injection were significantly larger in the pyrrolidone group. In conclusion, we successfully created a sufficient pneumoperitoneum state and obtained clear endoscopic images in the pyrrolidone-embalmed cadavers. Handling and dissection of the intra-abdominal structures with forceps closely replicated real-life surgery. These findings suggest the feasibility of laparoscopic training on cadavers embalmed with this pyrrolidone fixative.

Formalin or formaldehyde is commonly used for cadaver fixation, which is, however, not suitable for endoscopic transnasal skull base approach because of consequent hardening of the soft tissue. Several alternatives have been reported, but each of them also has some limitations. We applied a novel fixation method using N-vinyl-2-pyrrolidone (NVP), a precursor of the water-soluble macromolecular polymer, for endoscopic transnasal skull base approach in six donated cadaver specimens. In four cadavers, elasticity of the soft tissue in the nasal cavity was almost similar to that of living tissue, and a surgical approach similar to the real surgical field was possible. However, the soft tissue was moderately stiffer than living tissue in two specimens so that surgical manipulation was hindered to some extent while NVP concentration was 10% in all the cadavers. Since the brain tissue was too soft and pliable for surgical manipulation in NVP, more careful surgical manipulation than real surgical field was mandatory in order to prevent damage in the brain tissue. Therefore, this concentration of NVP was considered to be appropriate. In conclusion, NVP embalming was effective for endoscopic transnasal skull base approach in cadaver dissection, providing environment similar to the real surgical field.

The development of formalin-free fixatives is an urgent issue in gross anatomy because of the health hazard and the tissue-hardening actions of formalin. We recently identified the fixative, antimicrobial, and preservative effects of N-vinyl-2-pyrrolidone (NVP), a precursor of the water-soluble macromolecular polymer polyvinylpyrrolidone, in animal experiments. The aim of the present study is to investigate whether NVP solution can be used as an alternative to formalin in human cadaveric dissection. Twelve donated cadavers were infused with NVP via the femoral and common carotid arteries using a peristaltic pump. Experienced teaching staff members in our department dissected the cadavers and examined their macroanatomical properties. The NVP-embalmed corpses showed no sign of decomposition or fungal growth. The bodies remained soft and flexible. Notably, the shoulder, elbow, wrist, phalangeal, hip, knee, cervical spine, and temporomandibular joints were highly mobile, almost equivalent to those of living individuals. The range of motion of most joints was greater in the NVP-fixed than formalin-fixed cadavers. Under the dermis, the subcutaneous fat was markedly reduced and the connective tissues were transparent, so the ligaments, cutaneous nerves, and veins were easily discernible. The abdominal wall and the visceral organs remained pliable and elastic, resembling those of fresh cadavers. The lungs, liver, and gastrointestinal tract were moveable in the thoracic and abdominal cavities and were readily isolated. NVP can be used successfully as a fixative and preservative solution for human cadavers; furthermore, NVP-embalmed bodies could be valuable for learning clinical skills and for training, and for developing innovative medical devices. Clin. Anat. 31:90-98, 2018. © 2017 Wiley Periodicals, Inc.

Background and objective Mineralocorticoid receptor (MR) is a member of nuclear receptor family proteins and contributes to fluid homeostasis in the kidney. Although aldosterone-MR pathway induces several gene expressions in the kidney, it is often unclear whether the gene expressions are accompanied by direct regulations of MR through its binding to the regulatory region of each gene. The purpose of this study is to identify the direct target genes of MR in a murine distal convoluted tubular epithelial cell-line (mDCT). Methods We analyzed the DNA samples of mDCT cells overexpressing 3xFLAG-hMR after treatment with 10−7 M aldosterone for 1 h by chromatin immunoprecipitation with deep-sequence (ChIP-seq) and mRNA of the cell-line with treatment of 10−7 M aldosterone for 3 h by microarray. Results 3xFLAG-hMR overexpressed in mDCT cells accumulated in the nucleus in response to 10−9 M aldosterone. Twenty-five genes were indicated as the candidate target genes of MR by ChIP-seq and microarray analyses. Five genes, Sgk1, Fkbp5, Rasl12, Tns1 and Tsc22d3 (Gilz), were validated as the direct target genes of MR by quantitative RT-qPCR and ChIP-qPCR. MR binding regions adjacent to Ctgf and Serpine1 were also validated. Conclusions We, for the first time, captured the genome-wide distribution of MR in mDCT cells and, furthermore, identified five MR target genes in the cell-line. These results will contribute to further studies on the mechanisms of kidney diseases.

The aldosterone/mineralocorticoid receptor system plays an important role in the long-term blood pressure control through Na homeostasis. Its overactivation has been implicated in salt-sensitive hypertension. Excessive salt intake augments the function of mineralocorticoid receptor, despite lowering circulating aldosterone levels, but the mechanism had long been elusive. Recently, Rac1, a member of Rho family small GTP-binding proteins, has emerged as a novel ligand-independent modulator of mineralocorticoid receptor activity. In this review, the roles of Rac1 in the pathogenesis of salt-sensitive hypertension and kidney injury have been summarized.Genetic engineering studies have highlighted the new aspects of Rac1 and its regulators in salt-sensitive hypertension and cardiac and renal disease. New evidence shows the essential roles of Rac1 in salt-evoked paradoxical mineralocorticoid receptor activation observed in salt-sensitive models and in renal tubular Na reabsorption through reduced nicotinamide-adenine dinucleotide phosphate oxidase-mediated oxidative stress or direct regulation of Na transporters.The emerging concept of 'ligand-independent aberrant mineralocorticoid receptor activation by Rac1' in the pathogenesis of salt-sensitive hypertension and kidney injury has been reviewed. Rac inhibition, in addition to mineralocorticoid receptor blockade and salt restriction, would be a new promising strategy for the treatment of salt-sensitive hypertension.

Aldosterone has emerged as a deleterious hormone in the kidney, for example as a potent inducer of proteinuria. We identified the podocyte, the final filtration barrier in the glomerulus, as a novel target of aldosterone. Activation of the mineralocorticoid receptor (MR) in the podocyte disrupts the filtration barrier and induces proteinuria. Recent clinical and experimental studies have shown the efficacy of MR antagonism in reducing albuminuria in patients or rodent models of type 1 and type 2 diabetes. We assessed the pathogenic role of aldosterone in SHR/NDmcr-cp, a rat model of type 2 diabetes/metabolic syndrome. Podocyte injury and proteinuria were early manifestations of nephropathy in this model, and were exacerbated by high-salt feeding. Inappropriate activation of the aldosterone/MR system, possibly via adipocyte-derived aldosterone releasing factors, underlay the renal damage. Furthermore, we identified Rac1, a Rho family small GTPase, as a novel ligand-independent activator of MR. This alternative pathway of MR activation, indeed, contributed to podocyte injury in proteinuric kidney disease. In conclusion, MR can be activated by several different pathways, both aldosterone-dependently and -independently, leading to podocyte impairment and progression of proteinuric kidney disease. MR antagonists are promising anti-proteinuric drugs in diabetes, although hyperkalemia is a concern.

Recent clinical and experimental studies have shown that aldosterone is a potent inducer of proteinuria and that mineralocorticoid receptor (MR) antagonists confer efficient antiproteinuric effects. We identified glomerular epithelial cells (podocytes) as novel targets of aldosterone; activation of MR injures podocytes possibly via oxidative stress, resulting in disruption of glomerular filtration barrier, proteinuria, and progression of chronic kidney disease. We also demonstrated that SHR/cp, a rat model of metabolic syndrome, was susceptible to podocyte injury and proteinuria. Aldosterone excess caused by adipocyte-derived aldosterone-releasing factors was suggested to underlie the nephropathy. High salt intake augmented MR activation in the kidney and exacerbated the nephropathy. Furthermore, we identified an alternative pathway of MR activation by small GTPase Rac1. RhoGDIalpha knockout mice, a model with Rac1 activation in the kidney, showed albuminuria, podocyte injury, and glomerulosclerosis. Renal injury in the knockout mice was accompanied by enhanced MR signaling in the kidney despite normoaldosteronemia, and was ameliorated by an MR antagonist, eplerenone. Moreover, Rac-specific inhibitor significantly reduced the nephropathy, concomitantly with repression of MR activation. In vitro transfection studies provided direct evidence of Rac1-mediated MR activation. In conclusion, our findings suggest that MR activation plays a pivotal role in the pathogenesis of chronic kidney disease in metabolic syndrome, and that MR may be activated both aldosterone dependently (via aldosterone-releasing factors) and independently (via Rac1). MR antagonists are promising antiproteinuric drugs in metabolic syndrome, although long-term effects on renal outcomes, mortality, and safety need to be established.

Although inhibitors of the renin-angiotensin system are effective as first-line antihypertensive drugs in hypertensive patients with chronic kidney disease, they cannot completely prevent the progression of renal injury. Many animal studies, including our own, and a few human studies suggest that mineralocorticoid receptor blockade could inhibit the ongoing renal damage in chronic kidney disease. Thus, we designed this double-blinded, randomized, placebo-controlled trial to evaluate the antialbuminuric effect of a low dose (50 mg day(-1)) of the mineralocorticoid receptor antagonist eplerenone. The study subjects will include 340 hypertensive patients (blood pressure: 130-180/80-100 mm Hg) with albuminuria (urinary albumin/creatinine ratio: 30-600 mg g(-1) in the first morning void urine), who are treated with an inhibitor of the renin-angiotensin system. Other classes of antihypertensive drugs may be added as needed to achieve the target blood pressure (130/80 mm Hg). The primary study end point is the change in the urinary albumin/creatinine ratio after a 1-year study period. This trial is expected to show whether a low dose of mineralocorticoid receptor antagonists can exert an antialbuminuric effect in patients with chronic kidney disease.

Blockade of mineralocorticoid receptor has been shown to improve the clinical outcomes of proteinuric kidney diseases. However, little is known about the regulation of mineralocorticoid receptor-dependent transcriptional activity in renal disease. Here we identify a new role for Rac1, a member of the Rho family GTPases, as a potent activator of mineralocorticoid receptor signal transduction both in vitro and in vivo. Transient transfection assays in HEK 293 cells revealed that constitutively active Rac1 (CA-Rac1) enhanced mineralocorticoid receptor-dependent reporter activity, which was accompanied by increased nuclear translocation of mineralocorticoid receptor. CA-Rac1 facilitated mineralocorticoid receptor nuclear accumulation also in podocytes via p21-activated kinase phosphorylation. In mice lacking Rho GDP-dissociation inhibitor-alpha (Arhgdia(-/-) mice), renal abnormalities, including heavy albuminuria and podocyte damage, were associated with increased Rac1 (but not RhoA) and mineralocorticoid receptor signaling in the kidney, without alteration in systemic aldosterone status. Pharmacological intervention with a Rac-specific small-molecule inhibitor diminished mineralocorticoid receptor overactivity and renal damage in this model. Furthermore, albuminuria and histological changes in Arhgdia(-/-) mice were suppressed by mineralocorticoid receptor blockade, confirming the pathological role of Rac1-mineralocorticoid receptor interaction. Our results provide evidence that signaling cross-talk between Rac1 and mineralocorticoid receptor modulates mineralocorticoid receptor activity and identify Rac1 as a therapeutic target for chronic kidney disease.

Aldosterone is traditionally viewed as a hormone regulating electrolyte and blood pressure homeostasis by acting on the distal nephron. Accumulating evidence suggests that aldosterone also plays pathogenetic roles in cardiovascular and renal injury. For example, aldosterone is a potent inducer of proteinuria. We demonstrated that podocyte injury underlies the pathogenesis of proteinuria in aldosterone-infused rats on a high salt diet. Mineralocorticoid receptor was detected in the podocytes in vivo and in vitro, and aldosterone caused induction of its effector kinase Sgk1, activation of NADPH oxidase and generation of reactive oxygen species. Selective aldosterone blocker eplerenone, as well as antioxidant tempol, ameliorated aldosterone-induced podocyte injury and proteinuria. Aldosterone was also involved in the podocyte damage and proteinuria of metabolic syndrome model SHR/NDmcr-cp. Adipocyte-derived aldosterone releasing factors were suggested to contribute to the aldosterone excess of this model. Furthermore, high salt diet markedly worsened the renal injury of SHR/NDmcr-cp. Although salt lowered serum aldosterone levels, it caused MR activation in the kidney. Accordingly, eplerenone dramatically improved the salt-evoked nephropathy. Taken together, aldosterone blockers can be an excellent therapeutic strategy for the treatment of podocyte injury, proteinuria, and cardiovascular and renal complications, not only in high aldosterone states but also in patients with activated MR signaling in the target tissue, whose circulating aldosterone level is not necessarily high. Addition of aldosterone blockers in patients treated with ACEIs or ARBs are also promising, because of "aldosterone breakthrough" phenomenon. Careful monitoring of hyperkalemia is necessary, especially in patients with impaired renal function.

The Hedgehog family of proteins are powerful morphogens mediating embryonic development as well as adult morphogenesis and carcinogenesis. For example, excess hedgehog activity has been implicated in basal cell carcinoma, medulloblastoma and rhabdomyosarcoma. More recently, hedgehog signalling has been implicated in angiogenesis. While hedgehog signalling in adult angiogenesis may constitute a simple recapitulation of that in embryonic development, it should be appreciated that Hedgehog signalling occurs in embryonic angiogenesis in different developmental contexts. This article reviews the role of Hedgehog signalling in both embryonic and postnatal vascular development. The temporal importance of a window of hedgehog dependent angiogenesis during development is emphasised and illustrated using a whole mouse embryo culture system.

Although embryonic development is inevitably affected by biophysical or biomechanical processes, it has yet to be elucidated to what extent molecular mechanisms of development are modulated by such physical factors. The hedgehog family, including Sonic hedgehog (Shh), is the most well-known morphogens involved in the developmental pattern formation of various organs, such as the nervous system, face, limbs, and skin appendages. There are several unique features in hedgehog signaling including long-range diffusion or positive and negative feedback loops, suggesting the possible modification of hedgehog signaling by biophysical or biomechanical factors. Especially, the period of embryonic day 8-10 is characterized by various biomechanically regulated processes in mouse development, such as axial rotation and vasculoangiogenesis. We executed a series of experiments using a mouse whole embryo culture system to investigate the biomechanical roles of hedgehog signaling during this period. In this review, we examine various examples in which biophysical and biomechanical aspects of hedgehog signaling in development are revealed, including our own data using the mouse whole embryo culture system.

We examined a 59-year-old woman with a capillary malformation (CM) in her thigh, which was serially excised. Interestingly, the remnant CM after the first excision was enlarged at the time of the second excision. To investigate whether this phenomenon was caused by mere passive expansion or regrowth, the CM specimens of the first operation (nonexpanded) and the second operation (expanded) were examined. Expressions of angiogenic genes Tie2 and Angiopoietin-1 were up-regulated within the expanded CM compared with the nonexpanded lesion, suggesting angiogenesis in the expanded CM. Expression pattern of the endothelial marker von Willebrand factor and the capillary densities were unchanged after the excision, suggesting that angiogenesis seen in the expanded CM resulted in reorganization of vascular networks. We consider that our data support a hypothesis that the expanded lesion in this case was caused by regrowth, not a passive expansion, of the CM.

Podocyte injury is a major cause of proteinuria, a core component of chronic kidney disease. We reported that podocyte impairment underlied the early glomerulopathy in animal models of lifestyle-related diseases, such as hypertension and metabolic syndrome. Accumulating evidence suggests that overactivation of the aldosterone–mineralocorticoid receptor (MR) system has harmful effects on podocytes. We found that MR signaling was enhanced in such lifestyle-related diseases with podocyte injury and proteinuria, which were ameliorated by MR antagonist. Subsequent studies revealed that plasma aldosterone concentrations are not always increased in proteinuric conditions with renal MR activation, and the mechanisms of MR overactivation remained elusive. We recently identified a novel mechanism of Rac1-mediated podocyte impairment using RhoGDIα knockout mice; Rac1 potentiates the activity of MR in a ligand-independent manner, thereby accelerating podocyte injury. We demonstrated that the Rac1–MR pathway contributes to the ligand-independent aberrant MR activation in salt-sensitive hypertension and renal injury models. The importance of the RhoGDIα-Rac1-MR pathway in human glomerular disease is underscored by the findings that mutations in RhoGDIαgene cause nephrotic syndrome. Our results provide evidence that the Rac1-MR signal cascade as a novel therapeutic target for chronic kidney disease.

Adrenomedullin (AM) is a potent vasodilating peptide secreted from the vasculature of various organs. It is biologically active when its C-terminus is amidated. Recently, an RIA method was developed for measurement of the active form of AM, or mature AM. We here employed this method to investigate the significance of amidation of AM in controlling cardiovascular function. Thirty-six patients under hemodialysis were recruited and divided into hypertensive (n = 25; 157/86 mmHg) and normotensive (n= 11; 116/66 mmHg) groups. Mature AM, immature AM and blood pressure were monitored during hemodialysis in all patients. There was a significant reduction in blood pressure during hemodialysis in both groups, although after hemodialysis blood pressure was still higher in hypertensives than in normotensives (139 +/-14.8/76 +/- 2.5 mmHg vs. 110 +/- 5.1/66.7 +/- 3.1 mmHg). Mature AM before hemodialysis were lower in hypertensives than normotensives and it decreased in both groups. Although mature AM decreased more in normotensives than in hypertensives (-27 +/- 8% vs. -17 +/- 5%), at the end point, its level was still higher in normotensives. The ratio of mature AM/immature AM decreased only in normotensives (-11.4 8.7%), whereas it remained stable in hypertensives (0.2 +/- 5.6%). Both groups showed similar changes in ANP, endothelin, catecholamines, cGMP, and NOx. The low level in mature AM level in hypertensives may have contributed to the higher blood pressure in this group. The attenuation of AM amidation in normotensives indicates that an unspecified amidative enzyme of AM was regulated in order to normalize blood pressure.

The authors report the rare existence of a family that includes an older sister with Pfeiffer syndrome and a younger sister with achondroplasia. Gene analysis of these patients showed a T341P mutation in the FGFR2 gene in the patient with Pfeiffer syndrome, and a G380R mutation in the FGFR3 gene in the patient with achondroplasia. Both mutations have been reported previously. Their parents had no mutation in either locus. This result suggests the possibility that there may be predisposing factors for different FGFR mutations.

We report the identification of a unique repetitive sequence in the rat endothelial receptor for oxidized low-density lipoprotein (LOX-1) and unexpected blood-pressure-associated regulation of its expression, a new link between lipid metabolism and blood-pressure control. A rat aorta cDNA library was constructed and screened with a probe synthesized by degenerate PCR. Rat LOX-1 cDNA encoded a protein of 364 amino acids that showed ~ 60% similarity to its bovine and human counterparts. The protein consisted of intracellular N-terminal, transmembrane and extracellular lectin-like domains. Rat LOX-1 was unique in having three repeats of a 46-amino-acid motif between the transmembrane and lectin-like regions. Two isoforms of mRNA were found to be generated by alternative use of two polyadenylation signals in a tissue-specific manner. The 3ʹ-untranslated region contained multiple A+U-rich elements for rapid degradation of mRNA. Northern-blot analysis revealed that LOX-1 mRNA was expressed predominantly in the lung. Quite unexpectedly, the expression was dramatically up-regulated in the aorta in hypertensive SHR-SP/Izm rats compared with very low levels in control WKY/Izm rats, suggesting a potential role for LOX-1 in the pathogenesis of hypertension as well as atherosclerosis.

The renin-angiotensin-aldosterone system (RAAS) plays pivotal roles in the pathogenesis of chronic kidney disease (CKD) progression. Aliskiren, a direct renin inhibitor, inhibits the rate-limiting step of the RAAS without any alternative pathway. It is proven to reduce albuminuria in CKD patients treated with angiotensin blockade. However, there are few reports which evaluate the advantage of aliskiren as the first-line drug against CKD progression in RAAS-activated hypertensive patients.Tsukuba hypertensive mice (THM), double transgenic mice carrying both the human renin and human angiotensinogen genes, were fed a high-salt diet and treated with hydraladine, ramipril and aliskiren for 10 weeks. Blood pressure and urinary albumin excretion were measured every 2 weeks during the experimental period. We evaluated renal histological changes and gene expression. Plasma angiotensin concentration was measured to evaluate the RAAS inhibitory effect.High-salt-loaded THM showed severe hypertension and renal injury. All antihypertensive drugs suppressed blood pressure and prevented renal disease progression. RAAS blockade showed a higher renoprotective effect than hydraladine despite an equivalent blood pressure lowering effect. Aliskiren exhibited even stronger renoprotection than ramipril. Plasma angiotensin concentration was increased in THM fed both normal salt and high salt. Hydraladine did not alter the plasma angiotensin concentration. Ramipril significantly decreased angiotensin II concentration. Aliskiren treatment almost completely suppressed angiotensin I and resulted in lower angiotensin II concentration than ramipril treatment.Aliskiren prevents renal disease progression by suppressing both angiotensin I and II in RAAS-activated pathology. Our data suggest the application of a renin inhibitor for preventing kidney disease progression in CKD patients.

The mineralocorticoid receptor (MR) is a member of the steroid-responsive nuclear receptor family. Currently, in addition to its classical role in fluid homeostasis, attention has been focused on the pro-proteinuric and pro-inflammatory effects of MR in renal and cardiovascular diseases. Since proteinuria has been shown to be an important factor in the prognosis of patients with chronic kidney disease (CKD) [according to the newest Japanese Society of Nephrology and Kidney Disease: Improving Global Outcomes (KDIGO) guidelines for the treatment of CKD], it is worth discussing the role of MR in the progression of proteinuric CKD and the possible association with podocyte injury. Rac1, a Rho-GTPase family protein, is known for its role in the regulation of the cytoskeleton. We discovered the role of active Rac1 in amplifying MR activation in one of our studies and then continued to study how the Rac1−MR pathway contributes to the progression of kidney diseases. We then discovered the harmful effects of the activation of the Rac1−MR pathway in response to salt loading in the kidney for proteinuric kidney diseases of various animal models with salt-sensitive hypertension, such as Dahl salt-sensitive rats, RhoGDIα-knockout mice, angiotensin II-overproducing mice, and aldosterone-infused rats. In this review, we have introduced recent findings that suggest the contribution of MR activation to kidney diseases and the role of the Rac1−MR pathway in kidney injury associated with salt-sensitive hypertension and proteinuria. Thus, the Rac1−MR pathway is a potential therapeutic target in patients with proteinuric CKD.

The aldosterone-mineralocorticoid receptor (MR) system is traditionally considered as a system involved in the homeostatic regulation of body fluid and blood pressure in our body. A landmark clinical trial RALES caused a paradigm shift: growing attention has been focused on its role as a mediator of target organ damage. Recent studies clarified novel aspects of MR action in the pathophysiology of cardiac injury, through the analyses of genetically-engineered mice. My group focused on the anti-proteinuric effects of MR antagonist, and examined the role of MR overactivation in the progression of chronic kidney disease, and mechanisms of ligand-independent MR activation. In this paper, I would like to review the recent progress in the field of MR research.

Obesity hypertension and metabolic syndrome have become major public health concerns. Nowadays, aldosterone is recognized as an important mediator of cardiovascular and renal damage. In the kidney, aldosterone injures glomerular visceral epithelial cells (podocytes), the final filtration barrier to plasma macromolecules, leading to proteinuria and glomerulosclerosis. Mineralocorticoid receptor (MR) antagonists effectively ameliorate proteinuria in patients or in animal models of hypertension, diabetes mellitus and chronic kidney disease (CKD), as well as in patients who experience ‘aldosterone breakthrough.’ Recently, clinical and experimental studies have shown that plasma aldosterone concentration is associated with obesity hypertension and metabolic syndrome. We showed that spontaneously hypertensive rats (SHR)/cp, an experimental model of obesity hypertension and metabolic syndrome, are prone to glomerular podocyte injury, proteinuria and left ventricular diastolic dysfunction, especially when the animals are fed a high-salt diet. Inappropriate activation of the aldosterone/MR system underlies the renal and cardiac injuries. Adipocyte-derived aldosterone-releasing factors (ARFs), although still unidentified, may account for aldosterone excess and the resultant target organ complication in SHR/cp. On the other hand, recent studies have shown that MR activation triggers target organ disease even in normal or low aldosterone states. We identified a small GTP (guanosine triphosphate)-binding protein, Rac1, as a novel activator of MR, and showed that this ligand-independent MR activation by Rac1 contributes to the nephropathy of several CKD models. We expect that ARFs and Rac1 can be novel therapeutic targets for metabolic syndrome and CKD. Future large-scale clinical trials are awaited to prove the efficacy of MR blockade in patients with obesity hypertension and metabolic syndrome.

Adipose-derived stromal cells (ASCs) are one of the most promising stem cell populations that differentiate into the mesodermal as well as neural lineages in vitro. In this study, we examined the neural differentiating potential of human ASCs by a neurosphere culture method. Neurospheres derived from human ASCs expressed Nestin and Musashi-1 genes, which are marker genes for neural stem cells. When these cells were labeled with green fluorescent protein gene transfection by Sendai virus vector and transplanted into the head region of mouse embryos using a whole embryo culture system, these cells were incorporated into the craniofacial development. Some transplanted cells appeared to migrate along the second branchial arches, implicating some similarity to the cranial neural crest cells. Although preliminary, our results support an idea that ASC-derived neurospheres have properties of neural progenitors in vitro and in vivo.

Oxidized low-density lipoprotein (OxLDL) has been implicated in atherosclerosis and glomerulosclerosis. LOX-1 is a recently identified OxLDL receptor that is abundantly expressed in vascular endothelial cells. The aim of the present study was to investigate LOX-1 expression in the kidneys of hypertensive rats. Dahl salt-sensitive (DS) and salt-resistant (DR) rats were fed a 0.3% or 8% NaCl diet. Some DS 8% rats were treated with manidipine or hydralazine. LOX-1 gene expression was markedly elevated in the kidneys and glomeruli of hypertensive DS 8% rats compared with those of normotensive DR and DS 0.3% rats. Prolonged salt loading further increased the renal LOX-1 expression in DS rats. The LOX-1 upregulation in DS 8% rats was accompanied by renal overexpression of transforming growth factor-beta 1 and type I collagen, impaired renal function, and histologic glomerulosclerotic changes, all of which were ameliorated by antihypertensive treatment. LOX-1 was indeed expressed in the glomeruli in vivo and in cultured glomerular cells in vitro. However, LOX-1 expression was elevated in the aorta but not the kidneys of spontaneously hypertensive rats, which exhibited hypertension but minor glomerulosclerotic changes. In conclusion, the LOX-1 upregulation in the kidney of DS 8% rats was parallel to glomerulosclerotic changes and renal dysfunction, suggesting a possible pathogenetic role for renal LOX-1 in the progression to hypertensive glomerulosclerosis.

Objective To describe the 22nd case of Crouzan syndrome with acanthosis nigricans, a hyperkeratotic skin disorder with hyperpigmentation. Methods DNA analysis and sequencing of the FGFR3gene were performed. Results The 13-year-old Japanese boy described here also had dyspnea, facial palsy, sensorineural hearing loss, and skeletal and mental retardation. Examination of a skin biopsy specimen revealed the typical findings of acanthosis nigricans. Genetic analysis revealed the Ala391Glu mutation in one FGFR3 gene. Conclusions Crouzon syndrome with acanthosis nigricans is a distinct clinical entity different from classic Crouzon syndrome.

We examined the gene mutations of fibroblast growth factor receptor 2 (FGFR2) in Japanese syndromic Craniosynostotic patients. Subjects included 1 patient with Apert's syndrome, 1 patient with Crouzon's syndrome, and 3 patients with Pfeiffer's syndrome, as well as two control patients. The genomic deoxyribonucleic acid of each patient was extracted, and the mutation sites of the FGFR2 gene were amplified and sequenced. One patient with Apert's syndrome showed a FGFR2 mutation of S252W (TCG ± TGG), 1 patient with Crouzon's syndrome had a mutation of C342W (TGC ± TGG), and the 3 patients with Pfeiffer's syndrome had mutations of T341P (ACG ± CCG), C342S (TGC ± TCC), and D321A (GAC ± GCC). The role of FGF families and the effect of FGFR2 mutations on craniofacial morphogenesis are discussed.

To clarify the salt sensitivity of blood pressure in 17 alpha-hydroxylase deficiency (17 alpha-HD), a mineralocorticoid-induced hypertension, we examined the responses of blood pressure to salt loading (250 mEq/day for 6 days) after salt restriction (25 mEq/day for 3 days) in two 17 alpha-HD patients who had markedly high plasma deoxycorticosterone (DOC) (5.27 and 6.59 ng/mL; normal, 0.08 to 0.28) and corticosterone (B) (93 and 357 ng/mL; normal, 0.35 to 8.42). In case 1, moreover, the same study was repeated when plasma DOC and B restored to almost normal with the dexamethasone treatment (1 mg/day) (0.34 and 0.45 ng/mL). Salt loading elevated mean blood pressure markedly in both patients (14% and 20%), associated with cumulative sodium retention and body weight gain. Hemodynamic study showed marked increases in cardiac output (25% and 69%), but only slight decreases in systemic vascular resistance with salt loading. On the other hand, the treatment with dexamethasone could attenuate the salt-induced increase in blood pressure (2%), accompanied by lesser sodium retention, body weight gain, and elevation of cardiac output (7%) in case 1. The slope of the renal function curve for sodium excretion was decreased in these patients, and was restored toward normal by dexamethasone in case 1. We conclude that the patients with 17 alpha-HD showed salt-sensitive hypertension due to excessive DOC and B, through the impaired renal function for sodium excretion, disproportionate increase in cardiac output, and inadequate vasodilation.