• BMB Reports
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• 제46권4호
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• pp.230-235
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• 2013

Nephrin, a structural molecule, is also a signaling molecule after phosphorylation. Inhibition of nephrin phosphorylation is correlated with podocyte injury. The PINCH-1-ILK-${\alpha}$-parvin (PIP) complex plays a crucial role in cell adhesion and cytoskeleton formation. We hypothesized that nephrin phosphorylation influenced cytoskeleton and cell adhesion in podocytes by regulating the PIP complex. The nephrin phosphorylation, PIP complex formation, and F-actin in Wistar rats intraperitoneally injected with puromycin aminonucleoside were gradually decreased but increased with time, coinciding with the recovery from glomerular/podocyte injury and proteinuria. In cultured podocytes, PIP complex knockdown resulted in cytoskeleton reorganization and decreased cell adhesion and spreading. Nephrin and its phosphorylation were unaffected after PIP complex knockdown. Furthermore, inhibition of nephrin phosphorylation suppressed PIP complex expression, disorganized podocyte cytoskeleton, and decreased cell adhesion and spreading. These findings indicate that alterations in nephrin phosphorylation disorganize podocyte cytoskeleton and decrease cell adhesion through a PIP complex-dependent mechanism.

• Childhood Kidney Diseases
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• 제14권2호
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• pp.143-153
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• 2010

목 적 : 최근 신이식 환자들에서 cyclosporine A (CsA)의 대체로 sirolimus를 투여 받은 후 단백뇨가 발생한다는 임상보고가 있으나 단백뇨 발생기전의 정확한 메커니즘에 대한 연구가 없다. 이에 sirolimus에 의한 여러 단백뇨 발생기전 중 sirolimus와 CsA 투여 후 족세포의 세극막 관련 분자 변화를 조사하여 족세포와의 직접적인 영향에 대해 알아보고자 하였다. 방 법 : 생체 외 실험- 마우스 족세포를 완충액, CsA ($10\;{\mu}g/mL$) 처리 후 sirolimus ($10\;{\mu}g/mL$) 처리군, sirolimus 단독군, CsA와 sirolimus 동시 처리한 군으로 나누어 RT-PCR을 이용하여 12, 24, 48시간에 족세포의 세극막 관련 분자 변화를 측정하였다. 생체 내 실험- SPF Wistar 쥐 24마리를 각각 4군(완충액, CsA 2주 투여 후 sirolimus 2주간 투여, sirolimus 4주간 투여, CsA와 sirolimus를 4주간 동시투여)으로 분류하여 하루 걸러서 한번 복강 내 약물을 주입하였다(CsA: 25 mg/kg, sirolimus: 0.5 mg/kg). 모든 쥐는 약물주입 후 4주에 희생되어 병리조직은 오른쪽 신장의 일부분을 이용하고, 나머지 신장은 RT-PCR을 이용하여 세극막 관련 분자의 mRNA 발현 변화를 측정하였다. 결 과 : 생체 외 실험에서 CsA와 sirolimus 동시투여 또는 CsA 처리 후 sirolimus 처리군에서 nephrin 발현이 의미 있게 감소하였다. 생체 내 실험에서 nephrin 발현은 sirolimus를 사용한 모든 군에서, podocin 발현은 CsA와 sirolimus 동시투여 또는 CsA 처리 후 sirolimus 처리군에서 의미 있게 감소하였다. 광학현미경에서 CsA 투여군은 세뇨관 상피세포에서 공포형성 및 석회화가 관찰되었으며, 면역 조직화학검사에서 사구체 모세혈관의 nephrin, podocin항체 침착은 감소되지 않았다. CsA 투여군의 전자 현미경소견에서 사구체 족돌기의 국소적 융합이 있었으며, sirolimus 단독군에서는 특이소견이 없었다. 결 론 : 본 연구를 통해 sirolimus로 발생한 단백뇨의 많은 기전 중 하나로 sirolimus가 세극막 관련 분자 중 nephrin 및 podocin의 mRNA 발현을 감소시킬 수 있으며 sirolimus 단독보다는 CsA와 함께 작용했을 때 효과가 더 커질 수 있음을 제시하는 바이다.

• 대한소아신장학회:학술대회논문집
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• 대한소아신장학회 2006년도 제13차 추계학술대회 및 정기총회 초록집
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• pp.2-2
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• 2006

• 한국전자현미경학회:학술대회논문집
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• 한국현미경학회 2001년도 제32차 춘계학술대회
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• pp.82-83
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• 2001

• Nutrition Research and Practice
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• 제18권2호
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• pp.210-222
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• 2024

BACKGROUND/OBJECTIVES: Chronic renal failure (CRF) is a complex pathological condition that lacks a cure. Certain Chinese medicines, such as melittin, a major component in bee venom, have shown efficacy in treating CRF patients. On the other hand, the mechanisms underlying the therapeutic effects of melittin are unclear. MATERIALS/METHODS: A 5/6 nephrectomy model (5/6 Nx) of renal failure was established on rats for in vivo assays, and mouse podocyte clone 5 (MPC5) mouse podocyte cells were treated with angiotensin II (AngII) to establish an in vitro podocyte damage model. The 24-h urine protein, serum creatinine, and blood urea nitrogen levels were evaluated after one, 2, and 4 weeks. Hematoxylin and eosin staining, Masson staining, and periodic acid-Schiff staining were used to examine the pathological changes in kidney tissues. A cell counting kit 8 assay was used to assess the cell viability. Reverse transcription polymerase chain reaction and Western blot were used to assess the mRNA and protein levels in the cells, respectively. RESULTS: In the rat 5/6 Nx, melittin reduced the 24-h urinary protein excretion and the serum creatinine and blood urea nitrogen levels. Furthermore, the renal pathology was improved in the melittin-treated 5/6 Nx rats. Melittin promoted podocin, nephrin, Beclin 1, and the LC3II/LC3I ratio and inhibited phosphorylated mammalian target of rapamycin (mTOR)/mTOR in 5/6 Nx-induced rats and AngII-induced MPC5 mouse podocyte cells. Moreover, inhibiting autophagy with 3-MA weakened the effects of melittin on podocin, nephrin, and the LC3II/LC3I ratio in podocytes. CONCLUSION: Melittin may offer protection against kidney injury, probably by regulating podocyte autophagy. These results provide the theoretical basis for applying melittin in CRF therapy.

• 동의생리병리학회지
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• 제31권5호
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• pp.264-269
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• 2017

Prunella vulgaris, well-known traditional medicinal plant, is used for the cure of abscess, scrofula, hypertension and urinary diseases. Diabetic nephropathy is the most common cause of end-stage renal disease. The pathological characteristics of diabetic nephropathy are glomerular and tubular basement membrane thickening. The aim of the present study was to evaluate the effect of Prunella vulgaris, on diabetic glomerular injury in streptozotocin-induced diabetes rats. Diabetes mellitus was induced by a single intraperitoneal injection of streptozotocin (STZ; 45 mg/kg) and confirmed by random glucose level higher than ${\leq}300mg/dL$. The experimental rats were divided into five groups: control group (Male SD rats), STZ group (Male SD rats injected STZ), Aminoguanidine group (Male SD rats injected STZ + AG 100 mg/kg/day), Low dose group (Male SD rats injected STZ + APV 100 mg/kg/day), High dose group (Male SD rats injected STZ + APV 300 mg/kg/day). AG or APVs were administered once a day for 8 weeks. Body weight and food/water intake were measured every four weeks. At the end of study, the kidneys were collected and cut into pieces for immunohistochemistry and western blot analysis. Our study showed that body weight and water/food intake were no significant differences between untreated STZ-induced diabetic rat and APV treated-STZ rat. However, phosphorylation of receptor-regulated Smads (Smad3) was significantly decreased in APV treated-STZ rat as compared with the diabetic group. In addition, APV was improved nephrin level in kidney tissue. Therefore, we suggest that APV has a protective effect against STZ-induced diabetic glomerular injury.

• 동의생리병리학회지
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• 제34권2호
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• pp.61-66
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• 2020

Epithelial-mesenchymal transition (EMT) is the process by which epithelial cells lose their characters and acquire the properties of mesenchymal cells. EMT has been reported to exert an essential role in embryonic development. Recently, EMT has emerged as a pivotal mechanism in the metastasis of cancer and the fibrosis of chronic diseases. In particular, EMT is drawing attention as a mechanism of renal fibrosis in chronic kidney diseases such as diabetic nephropathy. In this study, we developed an EMT model by treating TGF-β1 on the podocytes, which play a key role in the renal glomerular filtration. This study explored the effects of Hwanggeum-tang (HGT) recorded in Dongeuibogam as being able to be used for the treatment of Sogal whose concept had been applied to Diabetes Mellitus (DM), on the TGF-β1-induced podocyte EMT. HGT suppressed the expression of vimentin and α-SMA, the EMT marker, in the human podocytes stimulated by TGF-β1. However, HGT increased the expression of ZO-1 and nephrin. Interestingly, HGT selectively inhibited the mTOR pathway rather than the classical Smad pathway. HGT also activated the AMPK signaling. HGT's inhibitory effect on the podocyte EMT through regulation of the mTOR pathway was achieved through the activation of AMPK, which was confirmed by comparison with cells treated with compound C (CC), an inhibitor of AMPK signaling. In conclusion, HGT can be applied to the renal fibrosis by preventing TGF-β1-induced EMT of podocytes through AMPK activation and mTOR inhibition.

• Journal of Ginseng Research
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• 제48권2호
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• pp.190-201
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• 2024

Background: Deposition of immune complexes drives podocyte injury acting in the initial phase of lupus nephritis (LN), a process mediated by B cell involvement. Accordingly, targeting B cell subsets represents a potential therapeutic approach for LN. Ginsenoside compound K (CK), a bioavailable component of ginseng, possesses nephritis benefits in lupus-prone mice; however, the underlying mechanisms involving B cell subpopulations remain elusive. Methods: Female MRL/lpr mice were administered CK (40 mg/kg) intragastrically for 10 weeks, followed by measurements of anti-dsDNA antibodies, inflammatory chemokines, and metabolite profiles on renal samples. Podocyte function and ultrastructure were detected. Publicly available single-cell RNA sequencing data and flow cytometry analysis were employed to investigate B cell subpopulations. Metabolomics analysis was adopted. SIRT1 and AMPK expression were analyzed by immunoblotting and immunofluorescence assays. Results: CK reduced proteinuria and protected podocyte ultrastructure in MRL/lpr mice by suppressing circulating anti-dsDNA antibodies and mitigating systemic inflammation. It activated B cell-specific SIRT1 and AMPK with Rhamnose accumulation, hindering the conversion of renal B cells into plasma cells. This cascade facilitated the resolution of local renal inflammation. CK facilitated the clearance of deposited immune complexes, thus reinstating podocyte morphology and mobility by normalizing the expression of nephrin and SYNPO. Conclusions: Our study reveals the synergistic interplay between SIRT1 and AMPK, orchestrating the restoration of renal B cell subsets. This process effectively mitigates immune complex deposition and preserves podocyte function. Accordingly, CK emerges as a promising therapeutic agent, potentially alleviating the hyperactivity of renal B cell subsets during LN.

• Childhood Kidney Diseases
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• 제9권2호
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• pp.119-127
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• 2005

목 적 : 단백뇨 질환에서 볼 수 있는 사구체 상피세포(glomerular epithelial cells, GEpC) 족돌기 사이에 위치한 세극막(slit diaphragm)의 P-cadherin의 당뇨조건에 따른 병리학적 변화를 알아보고자 하였다. 방 법 : 백서 GEpC을 배양하고 고농도의 당과 후기당화합물(advanced glycosylation endproducts, AGE)을 적용하여 당뇨병 환경에 가까운 조건을 설정한 후, p-cadherin 단백양은 Western 분석으로, 유전자 표현의 변화는 RT-PCR로 관찰하였다. 실험군은 당의 농도를 5 또는 30mM로, AGE와 BSA를 첨가하고 osmotic control로서 당 5 mM에 mannitol 25 mM을 섞은 것을 조합하여 A5, A30, B5, B30, Aosm로 하였다. 결 과 : P-cadherin 단백양은 B5 결과를 대조군으로 비교하여 당을 첨가한 B30에서 50.4$\%$의 감소, AGE를 추가한 조건인 A5와 A30에서 각각 7.4$\%$와 30.4$\%$의 의미 있는 감소를 보였다. 또한 P-cadherin mRNA의 표현은 B30에서 40.3$\%$의 감소, A30에서 27.2$\%$의 의의 있는 감소를 보였다. 이러한 감소 소견은 osmotic control(Aosm)에서는 관찰할 수 없었다. 결 론 : 고농도의 당과 AGE에 의한 GEpC의 P-cadherin을 유전자 수준에서의 억제로 단백의 생성 감소를 초래함으로써, 당뇨환경에서 세극막 성분의 변화를 설명할 수 있으며, 추후 이의 변화 기전에 대한 연구가 필요할 것으로 사료된다.