나기영 교수

While hyperosmolality of the kidney medulla is essential for urinary concentration, it imposes a great deal of stress. Cells in the renal medulla adapt to the stress of hypertonicity (hyperosmotic salt) by accumulating organic osmolytes. Tonicity-responsive enhancer (TonE) binding protein (TonEBP) (or NFAT5) stimulates transcription of transporters and a synthetic enzyme for the cellular accumulation of organic osmolytes. We found that dominant-negative TonEBP reduced expression of HSP70 as well

Thiazides have been used in patients with nephrogenic diabetes insipidus (NDI) to decrease urine volume, but the mechanism by which it produces the paradoxic antidiuretic effect remains unclear. Previous studies have reported that downregulation of aquaporin-2 (AQP2) is important for the development of lithium-induced (Li-induced) polyuria and that hydrochlorothiazide (HCTZ) increases renal papillary osmolality and Na(+) concentration in Brattleboro rats. For elucidating the molecular basis of t

The present study indicates that the recommendation of low BMI as a means of obtaining a survival advantage in the elderly is not supported. Instead, higher lean mass and higher LMI are associated with better survival in the elderly Asian population.

Several studies have suggested a potential effect of serum bilirubin as an antioxidant and cytoprotectant factor. For the results presented here, we evaluated the correlation between serum bilirubin and diabetes mellitus (DM) or chronic kidney disease originated from DM (DMCKD) in a Korean population. We used a cross-sectional, population-based design to examine 93,909 subjects (aged 18-96 years, 53.0% male). The trend of P values in the odds ratios for being DM and DMCKD was calculated using pa

Furosemide and hydrochlorothiazide (HCTZ) exert their diuretic actions by binding to apical Na(+) transporters, viz., the Na(+)-K(+)-2Cl(-) cotransporter in the thick ascending limb and the Na(+)-Cl(-) cotransporter in the distal convoluted tubule, respectively. We carried out semiquantitative immunoblotting and immunohistochemistry of rat kidneys to investigate whether chronic administration of furosemide or HCTZ is associated with compensatory changes in the abundance of Na(+) transporters dow

In rat remnant kidneys, DPP IV inhibitor attenuated renal dysfunction and structural damage. A reduction of apoptosis, inflammation and an increase of antioxidant could be suggested as a renoprotective mechanism together with the activation of FoxO3a signaling. Therefore, DPP IV inhibitors might provide a promising approach for treating CKD, but their application in clinical practice remains to be investigated.

Acute kidney injury (AKI) is a major health concern, because AKI is related with an increase in morbidity and mortality. Anemia is related to AKI in several clinical settings. However, the relationship between anemia and AKI and the effect of anemia on long-term mortality are unresolved in critically ill patients. A total of 2,145 patients admitted to the intensive care unit were retrospectively analyzed. We calculated a threshold value of hemoglobin associated with an increased risk of AKI and

The initial pump speed of ECMO was a significant risk factor of in-hospital mortality and AKI in patients receiving ECMO. The RDW was a risk factor of stage 3 AKI.

AKI duration is an additional parameter for the prediction of mortality in critically ill patients. The inclusion of AKI duration could be considered as a refinement of the AKI criteria.

TonEBP is a transcriptional activator that is expressed throughout development in many tissues and cell types. In the kidney medulla, TonEBP appears to be an important local regulator of differentiation by virtue of stimulating several genes. To study the function of TonEBP, two small interfering RNA (siRNA) duplexes were developed that reduced TonEBP expression effectively via RNA interference. The silencing lasted only 3 d after introduction of the TonEBP-siRNA's. As expected, TonEBP-driven re

Gentamicin nephrotoxicity is one of the most common causes of acute kidney injury (AKI). Hypoxia-inducible factor (HIF) is effective in protecting the kidney from ischemic and toxic injury. Increased expression of HIF-1α mRNA has been reported in rats with gentamicin-induced renal injury. We hypothesizd that we could study the role of HIF in gentamicin-induced AKI by modulating HIF activity. In this study, we investigated whether HIF activation had protective effects on gentamicin-induced renal

Tonicity-responsive enhancer binding protein (TonEBP), also known as NFAT5, belongs to the Rel family of transcriptional activators. In the kidney medulla and thymus, TonEBP plays a major role in protecting renal cells and T cells from the deleterious effects of ambient hypertonicity. TonEBP is stimulated by hypertonicity via several pathways: increased expression of protein, nuclear translocation, and increased transactivation. In this study, we identified five domains of TonEBP involved in tra

Recent progress in molecular physiology has permitted us to understand pathophysiology of various channelopathies at a molecular level. The secretion of H(+) from alpha-intercalated cells is mediated by apical plasma membrane H(+)-ATPase and basolateral plasma membrane anion exchanger-1 (AE1). Studies have demonstrated the lack of H(+)-ATPase immunostaining in the intercalated cells in a few patients with distal renal tubular acidosis (dRTA). Mutations in H(+)-ATPase and AE1 gene have recently b