Induction of apoptosis and cell cycle arrest in human HCC MHCC97H cells with Chrysanthemum indicum extract

AIM： To investigate the effects of Chrysanthemum indicum extract （CIE） on inhibition of proliferation and on apoptosis, and the underlying mechanisms, in a human hepatocellular carcinoma （HCC） MHCC97H cell line. METHODS： Viable rat hepatocytes and human endothelial ECV304 cells were examined by trypan blue exclusion and MTT assay, respectively, as normal controls. The proliferation of MHCC97H cells was determined by MTT assay. The cellular morphology of MHCC97H cells was observed by phase contrast microscopy. Flow cytometry was performed to analyze cell apoptosis with annexin V/propidium iodide （PI）, mitochondrial membrane potential with rhodamine 123 and cell cycle with PI in MHCC97H cells. Apoptotic proteins such as cytochrome C, caspase-9, caspase-3 and cell cycle proteins, including P21 and CDK4, were measured by Western blotting. RESULTS： CIE inhibited proliferation of MHCC97H cells in a timeand dose-dependent manner without cytotoxicity in rat hepatocytes and human endothelial ceils. CIE induced apoptosis of MHCC97H cells in a concentration-dependent manner, as determined by flow cytometry. The apoptosis was accompanied by a decrease in mitochondrial membrane potential, release of cytochrome C and activation of caspase-9 and caspase-3. CIE arrested the cell cycle in the S phase by increasing P21 and decreasing CDK4 protein expression. CONCLUSION： CIE exerted a significant apoptotic effect through a mitochondrial pathway and arrested the cell cycle by regulation of cell cycle-related proteins in MHCC97H cells without an effect on normal cells. The cancer-specific selectivity shown in this study suggests that the plant extract could be a promising novel treatment for human cancer.     

Givinostat inhibition of hepatic stellate cell proliferation and protein acetylation

AIM: To explore the effect of the histone deacetylase inhibitor givinostat on proteins related to regulation of hepatic stellate cell proliferation.METHODS: The cell counting kit-8 assay and flow cytometry were used to observe changes in proliferation, apoptosis, and cell cycle in hepatic stellate cells treated with givinostat. Western blot was used to observe expression changes in p21, p57, CDK4, CDK6, cyclin D1, caspase-3, and caspase-9 in hepatic stellate cells exposed to givinostat. The scratch assay was used to analyze the effect of givinostat on cell migration. Effects of givinostat on the reactive oxygen species profile, mitochondrial membrane potential, and mitochondrial permeability transition pore opening in JS-1 cells were observed by laser confocal microscopy.RESULTS: Givinostat significantly inhibited JS-1 cell proliferation and promoted cell apoptosis, leading to cell cycle arrest in G0/G1 phases. Treatment with givinostat downregulated protein expression of CDK4, CDK6, and cyclin D1, whereas expression of p21 and p57 was significantly increased. The givinostat-induced apoptosis of hepatic stellate cells was mainly mediatedthrough p38 and extracellular signal-regulated kinase 1/2. Givinostat treatment increased intracellular reactive oxygen species production, decreased mitochondrial membrane potential, and promoted mitochondrial permeability transition pore opening. Acetylation of superoxide dismutase(acetyl K68) and nuclear factor-κB p65(acetyl K310) was upregulated, while there was no change in protein expression. Moreover, the notable beneficial effect of givinostat on liver fibrosis was also confirmed in the mouse models.CONCLUSION: Givinostat has antifibrotic activities via regulating the acetylation of nuclear factor-κB and superoxide dismutase 2, thus inhibiting hepatic stellate cell proliferation and inducing apoptosis.     

Blocking effects of genistein on cell proliferation and possible mechanism in human gastric carcinoma

AIM: To study the blocking effects of genistein on cell proliferation cycle in human gastric carcinoma cells (SGC-7901) and the possible mechanism. METHODS: MTT assay was applied in the detection of the inhibitory effects of genistein on cell proliferation. Flow cytometry was used to analyze the cell cycle distribution. Immunocytochemical technique and Western blotting were performed to detect the protein expression of cyclin D_1, cyclin B_1 and p21~(waf1/cip1). RESULTS: Genistein significantly inhibited the growth and proliferation of human gastric carcinoma cells (SGC-7901). Seven days after treatment with different concentrations of genistein (2.5, 5.0, 10.0, 20.0 μg/mL), the growth inhibitory rates were 11.2%, 28.8%, 55.3%, 84.7% respectively and cell cycles were arrested at the G(2)/ M phase. Genistein decreased cyclin D_1 protein expression and enhanced cyclin B_1 and p21~(waf1/cip1) protein expression in a concentration-dependent manner. CONCLUSION: The growth and proliferation of SGC-7901 cells can be inhibited by genistein via blocking the cell cycle, with reduced expression of cyclin D_1 and enhanced expression of cyclin B_1 and p21~(waf1/cip1) protein in the concentration range of 0-20 μg/mL.     

Mechanisms of trichostatin A inhibiting AGS proliferation and identification of lysine-acetylated proteins

AIM: To explore the effect of lysine acetylation in related proteins on regulation of the proliferation of gastric cancer cells, and determine the lysine-acetylated proteins and the acetylated modified sites in AGS gastric cancer cells. METHODS: The CCK-8 experiment and flow cytometry were used to observe the changes in proliferation and cycle of AGS cells treated with trichostatin A (TSA). Real time polymerase chain reaction and Western blotting were used to observe expression changes in p21, p53, Bax, Bcl-2, CDK2, and CyclinD1 in gastric cancer cells exposed to TSA. Cytoplasmic proteins in gastric cancer cells before and after TSA treatment were immunoprecipitated with anti-acetylated lysine antibodies, separated using sodium dodecyl sulfate polyacrylamide gel electrophoresis gel and silver-stained to detect the proteins by mass spectrometry after removal of the gel. The acetylated proteins in AGS cells were enriched with lysine-acetylated antibodies, and a high-resolution mass spectrometer was used to detect the acetylated proteins and modified sites. RESULTS: TSA significantly inhibited AGS cell proliferation, and promoted cell apoptosis, leading to AGS cell cycle arrest in G0/G1 and G2/M phases, especially G0/G1 phase. p21, p53 and Bax gene expression levels in AGS cells were increased with TSA treatment duration; Bcl-2, CDK2, and CyclinD1 gene expression levels were decreased with TSA treatment duration. Two unknown protein bands, 72 kDa (before exposure to TSA) and 28 kDa (after exposure to TSA), were identified by silver-staining after immunoprecipitation of AGS cells with the lysine-acetylated monoclonal antibodies. Mass spectrometry showed that the 72 kDa protein band may be PKM2 and the 28 kDa protein band may be ATP5O. The acetylated proteins and modified sites in AGS cells were determined. CONCLUSION: TSA can inhibit gastric cancer cell proliferation, which possibly activated signaling pathways in a variety of tumor-associated factors. ATP5O was obviously acetylated in AGS cells following TSA treatm     

Effect of p27(KIP1) on cell cycle and apoptosis in gastric cancer cells

AIM: To elucidate the effect of p27KIP1 on cell cycle and apoptosis regulation in gastric carcinoma cells. METHODS: The whole length of p27KIP1 cDNA was transfected into human gastric cancer cell line SCG7901 by lipofectamine. Expression of p27KIP1 protein or mRNA was analyzed by Western blot and RNA dot blotting, respectively. Effect of p27KIP1 on cell growth was observed by MTT assay and anchorage-independent growth in soft agar. Tumorigenicity in nude mice was used to assess the in vivo biological effect of p27KIP1. Flow cytometry, TUNEL, and electron microscopy were used to assess the effect of p27KIP1 on cell cycle and apoptosis. RESULTS: Expression of p27KIP1 protein or mRNA increased evidently in SCG7901 cells transfected with p27KIP1. The cell growth was reduced by 31% at 48 h after induction with zinc determined by cell viability assay. The alteration of cell malignant phenotype was evidently indicated by the loss of anchorage-independent growth ability in soft agar. The tumorigenicity in nude mice was reduced evidently (0.55±0.14 cm vs 1.36±0.13 cm, P<0.01). p27KIP1 overexpression caused cell arrest with 36% increase (from 33.7% to 69.3%, P<0.01) in G1 population. Prolonged p27KIP1 expression induced apoptotic cell death reflected by pre-G1 peak in the histogram of FACS, which was also confirmed by TUNEL assay and electron microscopy. CONCLUSION: p27KIP1 can prolong cell cycle in G1 phase and lead to apoptosis. p27KIP1 may be a good candidate for cancer gene therapy.     

Mechanism of apoptotic effects induced selectively by ursodeoxycholic acid on human hepatoma cell lines

AIM: To investigate the effects of ursodeoxycholic acid (UDCA) on apoptosis and proliferation of hepatoma cell lines. METHODS: Human hepatoma cell lines HepG2 and BEL 7402 were cultured in medium supplemented with different concentrations of UDCA, normal human hepatic line L-02 was used as control. Cell proliferation, apoptosis and gene expression were detected using methyl thiazolyl tetrazolium (MTT) assay, flow cytometry, Western blot, DNA ladder assay, electron microscopy, and immunocytochemistry. RESULTS: Ursodeoxycholic acid inhibited the proli- feration of HepG2 and BEL7402 cell lines in a dose- dependent manner. Ursodeoxycholic acid can change cell cycle distribution of HepG2 and BEL7402, the proportion of cells in G0-G1 phase increased whereas the proportion of S phase cells and G2-M phase cells decreased. Ursodeoxycholic acid arrested the cell cycle in G0-G1 phase by down-regulating the cell cycle related proteins cyclin D1, D3 and retinoblastoma protein (pRb). The apoptotic rates of HepG2 and BEL7402 treated with UDCA (1.0 mmol/L) were significantly higher than those of control. In the HepG2 and BEL7402 treated with UDCA, expression of bcl-2 decreased whereas expression of Bax increased, the nuclear fragmentation and chromosomal condensed, cells shrank and lost attachment, apoptotic bodies and DNA ladders appeared. UDCA had no effect in inducing apoptosis on L-02 cell lines. CONCLUSION: UDCA can selectively inhibit proliferation and induce apoptosis of HepG2 and BEL7402 cell lines by blocking cell cycle and regulating the expression of Bax/bcl-2 genes.     

CIP/KIP族细胞周期蛋白激酶抑制剂与糖尿病肾病

细胞周期素激酶抑制剂(CKIs)是细胞周期的负调控蛋白,其CIP/KIP家族表达异常在糖尿病肾病早期发病中起着重要作用.高糖、血管紧张素-Ⅱ(Ang-Ⅱ)、转化生长因子-β(TGF-β)等均可影响其表达.CKIs通过抑制细胞周期素激酶(CDK)活性使细胞停留于G1期,引起肾脏细胞肥大,与晚期肾小球及肾小管间质纤维化有密切关系.明确CKIs在糖尿病肾病早期发病中的作用将为糖尿病肾病早期防治提供有力的理论依据.     

Negatively regulating mechanism of Sirpal in hepatocellular carcinoma:an experimental study

BACKGROUND: Signal regulatory protein ( Sirp) is a recently isolated, cloned and identified inhibitor receptor distributed in the membrane of hematopoietic and nonhema-topoietic cells. Sirp alphal ( Sirpα1) is a member of Sirp families. Sirpal can bind SHP-2 in the form of tyrosine phosphorylation by SH2 effect and negatively regulate growth factor, oncogene, or insulin-induced responses as its substrate. This study aimed to preliminarily clarify the negatively regulating proliferation mechanism of Sirpal in liver cancer. METHODS: pLXSN, Sirpα1 and Sirpα1Δ4Y2 plasmids were respectively transfected into Sk-Hepl liver cancer cell line, and various stable Sk-Hepl cell lines were obtained with screening agent of G418 (1200 μg/ml). The expressing levels of cyclin D1, CDK4, Fas, β-catenin and gankyrin in various cell lines were determined with Western blotting. Cell cycles were determined at 0, 12 and 24 hours with flow cytotnetry after various synchronous cell lines were cultured without serum for 72. Cell apoptosis induced with agent of TNF-α (50 ng/ml) was determined with flow cytotnetry at 0,0.5,1,3,6 and 12 hours. RESULTS: Sirpα1 could significantly decrease the expression of cyclin D1, β-catenin and gankyrin, but it couldn't affect the expression level of CDK4 and Fas. When synchronous cells were cultured for 12 hours, S phase Sk-Hep1 cell transfected with Sirpal plasmid was the lowest [(31.92 ± 0.22)% vs. other cell lines, P <0.05], and the cell line was highly sensitive to TNF-α agent for 1 hour. (59.31 ±0.59)% of apoptotic cells occurred (vs. the other time points, P < 0.05). CONCLUSIONS: Sirpal might block the cell cycle of liver cancer, inhibit cell proliferation, promote cell apoptosis by decreasing the expression of cyclin D1, β-catenin and gankyrin. It is one of the important mechanisms inhibiting the occurrence and development of hepatocellular carcinoma.     

肺表面活性物质对哮喘T细胞亚群细胞周期及其调节蛋白的影响

目的 观察肺表面活性物质(PS)对发作期哮喘患者T细胞亚群细胞周期及其调节蛋白的影响,揭示PS对CD4+、CD8+T细胞增殖周期的具体作用机制及其在哮喘治疗中的意义.方法 利用细胞培养技术,通过体外PS干预,流式细胞仪测定经PS干预和未经PS干预的CD4+、CD8+T细胞的细胞周期分布和CD4+、CD8+T细胞内细胞周期调节蛋白p27kipl、cyclinE、cyclinA、cyclinB的表达水平.结果 哮喘患者CD4+、CD8+T细胞分别与PS体外共同培养后,加PS组的S期、G2/M期的CD4+T比例显著低于对照组(P＜0.01);G0/G1期的CD4+T细胞比例显著高于对照组(P＜0.01).加PS组的S期CD8+T比例显著低于对照组(P＜0.01);G2期的CD8+T细胞比例略低于对照组,但差异无统计学意义(P＞0.05);G0/G1期的CD8+T细胞比例高于对照组(P＜0.05).CD4+T细胞内p27kipl的表达水平高于对照组(P＜0.05);CD4+T细胞内cyclinE表达水平显著低于对照组(P＜0.01);CD4+T细胞内cyclinA、cyclinB的表达水平低于对照组(P＜0.05).CD8+T细胞内p27kipl的表达水平高于对照组(P＜0.05);CD8+T细胞内cyclinE、cyclinA表达水平低于对照组(P＜0.01);CD8T细胞内cyclinB的表达水平与对照组差异无统计学意义(P＞0.05).结论 PS通过抑制CD4+T细胞的正性细胞周期调节蛋白cyclinE、cyclinA、cyclinB的表达和上调其负性细胞周期调节蛋白p27kipl的表达,抑制CD4+T细胞的DNA合成和细胞分裂,进而抑制CD4+T细胞增殖;通过下调CD8+T细胞内cyclinE、cyclinA的表达,上调p27kippl的表达,抑制CD8+T细胞DNA合成.

Abstract：

Objective The aim of this study was to observe the effect of pulmonary surfactant (PS)on the cell cycle distribution and expression of cell cycle regulatory proteins in T lymphocyte subsets in patients with asthma attack and evaluate the molecular regulatory mechanism of PS on T lymphocyte subsets cell proliferation cycle during asthma attack and its therapy significance. Methods The CD4+、CD8+ T lymphocytes obtained from peripheral blood of 30 patients with asthma attack were incubated with PS,the cell cycle and the expression of p27kipl , CyclinE, CyclinA, CyclinB in CD4+ , CD8+ T lymphocytes with PS and without PS were anasyzed by flow cytometry. Results CD4 + T lymphocytes with PS progressed into S phase and G2/M phase were significantly lower than those without PS( P ＜0.01). But remained in G0/G1 phase were significantly higher than those without PS (P ＜ 0.01). CD8+ T lymphocytes with PS progressed into S phase were significantly lower than those without PS( P ＜0.01),G2/M phase were little lower than those without PS( P ＞ 0.05), Go/G1 phase were higher than those without PS( P ＜0.05). The expression of p27kipl in CD4+T lymphocytes with PS was higher than that without PS( P ＜0.05). The expression of cyclinE in CD4+ T lymphocytes with PS was significantly lower than that without PS( P ＜0.01 ). The expression of cyclinA,cyclinB in CD4+ T lymphocytes with PS were lower than those without PS( P ＜0.05). The expression of p27kipl in CD8+ T lymphocytes with PS was higher than that without PS( P ＜0.05). The expression of cyclinE and cyclinA in CD8+ T lymphocytes with PS were significantly lower than that without PS( P ＜0. 01). The expression of cyclinB in CD8+ T lymphocytes with PS was little lower than that without PS( P ＞0.05). Conclusions During asthma attack,PS can inhibit the DNA synthesis, cell division and proliferation of CD4+T lymphocytes by inhibiting positive cell cycle regulatory proteins cyclinE, cyclinA, cyclinB expression and increasing negative cell cycle regulatory protein p27kipl expression in CD4+ T lymphocytes. PS can inhibit the DNA synthesis of CD8+ T lymphocytes by inhibiting positive cell cycle regulatory proteins cyclinE, cyclinA,expression and increasing negative cell cycle regulatory protein p27kipl expression in CD8+ T lymphocytes.     

P27kip1在糖尿病肾病中的作用

细胞周期激酶抑制剂p27kip1是一种细胞周期调节蛋白,对细胞生长具有重要的调控作用.实验证实,糖尿病肾病动物肾小球和体外高糖培养的肾脏固有细胞内,p27kip1水平明显增加.P27kip1通过调控肾脏固有细胞的增殖、肥大、凋亡等,参与糖尿病肾病的发生和发展,因此调控p27kip1的水平将有助于改善早期糖尿病肾病.     

Growth factors and the development of diabetic nephropathy

Growth factors play an important role in the development of functional and structural changes associated with diabetic nephropathy. Although it has been known for years that these factors are important for early renal hypertrophy and subsequent development of glomerulosclerosis and tubulointerstitial fibrosis, the exact molecular mechanism of many of these factors has only recently been more elucidated. Furthermore, growth factors also link the metabolic theory of diabetic complications with renal hemodynamic changes in diabetic nephropathy because some growth factors could directly influence glomerular hemodynamics and tubular transport in diabetic nephropathy. The high glucose environment with stimulated cellular uptake of glucose and accelerated nonenzymatic reactions resulting in Amadorimodified proteins and the later-developing advanced glycation end products are the main stimulators for intrarenal induction of growth factors. Intracellular generation of reactive species is an important signal intermediate in these stimulated expressions of growth factors. Taking into consideration the pivotal role of growth factors in the development of diabetic nephropathy, a therapeutic strategy to antagonize growth factor effects appears to be straightforward. However, the pleiotropic function of many of these factors and their physiologic role in normal renal homeostasis may make this approach difficult.     

非胰岛素依赖型糖尿病肾病肾组织中EGF、EGF－R和IGF－1R的检测及其意义

应用免疫组织化学定量分析的方法，对１２例胰岛素非依赖型糖尿病（ＮＩＤＤＭ）肾病患者肾活检组织中胰岛素样生长因子－１（ＩＧＦ－１）受体、表皮生长因子（ＥＧＦ）和表皮生长因子受体（ＥＧＦ－Ｒ）进行了观察，并结合患者的病程、糖尿病肾病分期和肾功能进行了比较。ＮＩＤＤＭ肾病患者肾小管上ＥＧＦ和ＥＧＦ－Ｒ的量明显高于正常人，部分患者肾小球ＥＧＦ也呈阳性反应。正常人和ＮＩＤＤＭ肾病患者肾小管上ＩＧＦ－１受体的量则无明显差异。提示肾小管上ＥＧＦ和ＥＧＦ－Ｒ含量增加可能参与ＮＩＤＤＭ肾病的发病过程，而肾小球内ＥＧＦ的出现与系膜细胞和系膜基质增生有关。     

Novel roles of the IGF-IGFBP axis in etiopathophysiology of diabetic nephropathy

Mechanisms contributing to development of diabetic nephropathy (DN) remain unclear. High ambient glucose level transforms intracellular pathways, promoting stable phenotypic changes in the glomerulus such as mesangial cell hypertrophy, podocyte apoptosis, and matrix expansion. Insulin-like growth factors (IGFs) and the high affinity IGF binding proteins (IGFBPs) exert major effects on cell growth and metabolism. Compared with diabetic patients without microalbuminuria (MA), MA diabetic patients display perturbed GH-IGF-IGFBP homeostasis, including increased circulating IGF-I and IGFBP-3 protease activity, increased excretion of bioactive GH, IGF-I, and IGFBP-3, but decreased circulating IGFBP-3 levels. In diabetic animal models, expression of IGF-I and IGFBP-1 to -4 increases in key renal tissues and glomerular ulrafiltrate. Epithelial, mesangial, and endothelial cells derived from the kidney respond to IGF-I binding with increased protein synthesis, migration, and proliferation. This article reviews classic and emerging concepts for the roles of the GH-IGF-IGFBP axis in the etiopathophysiology, treatment, and prevention of diabetic renal disease. We report IGF-independent actions of IGFBP-3 in the podocyte for the first time.     

AT1 receptor antagonists: a challenge for ACE inhibitors in diabetic nephropathy

Due to its hemodynamic, metabolic and growth promoting effects, angiotensin II (AII) may play an important role in the pathogenesis of diabetic kidney disease. Consequently, decreasing the production or cellular action of AII is a rational target for therapeutic attempts aimed at slowing the progression of diabetic nephropathy. Based on their superior renoprotective performance in recent landmark studies, currently ACE inhibitors are the drugs of choice in diabetic patients with microalbuminuria or overt proteinuria. A new class of antihypertensive medications, the AT1 receptor antagonists may represent an alternative to ACE inhibitors in the treatment of diabetic nephropathy. They provide a more complete blockade of the renal renin‐angiotensin system and are generally better tolerated than ACE inhibitors. On the other hand, AT1 receptor antagonists do not increase bradykinin levels, an effect that may contribute to the high level of renoprotection achieved by ACE inhibitors. Although human data are not available at this point, ACE inhibitors and AT1 receptor antagonists have similar beneficial effects on proteinuria, renal hypertrophy and glomerulosclerosis in animal models of diabetic kidney disease. Currently several prospective studies are being conducted to compare the efficacy of ACE inhibitors and AT1 receptor antagonists in the treatment of human diabetic nephropathy. Copyright © 1999 John Wiley & Sons, Ltd.     

eIF4E as a Control Target for Viruses

Translation is a complex process involving diverse cellular proteins, including the translation initiation factor eIF4E, which has been shown to be a protein that is a point for translational regulation. Viruses require components from the host cell to complete their replication cycles. Various studies show how eIF4E and its regulatory cellular proteins are manipulated during viral infections. Interestingly, viral action mechanisms in eIF4E are diverse and have an impact not only on viral protein synthesis, but also on other aspects that are important for the replication cycle, such as the proliferation of infected cells and stimulation of viral reactivation. This review shows how some viruses use eIF4E and its regulatory proteins for their own benefit in order to spread themselves.     

Angiotensin II and cell cycle regulation

Angiotensin II has emerged as an important growth factor for vascular, cardiac, and renal cells. Depending on the specific cell type and presence of other growth factors, angiotensin II induces proliferation (replication of DNA with subsequent successful division of cells), hypertrophy (increase in cell size, cell protein, and mRNA content without DNA replication), apoptosis (programmed cell death), or differentiation. Such angiotensin II-mediated modulation of growth process may underlie various pathophysiological processes such as atherosclerosis, vascular and cardiac remodeling, and progression of chronic renal disease. Clearly, angiotensin II-induced proliferation requires complete cell progression through the various steps of the cell cycle. In contrast, cells undergoing angiotensin II-mediated hypertrophy are arrested in the G1-phase. Upregulation of cell cycle-dependent kinase inhibitors (eg, p27Kip1) plays an important role in this process. Although accumulating evidence suggests that apoptosis is cell cycle-dependent, only few data are currently available concerning the interaction of angiotensin II with the cell cycle machinery in apoptosis. We review the various angiotensin II-mediated growth processes and their relationship to events governing cell cycle regulation.     

胰高血糖素与2型糖尿病及其肾病的关系

胰高血糖素是调控糖代谢平衡的重要激素之一,血清胰高血糖素的异常升高与2型糖尿病的起始和进展相关.糖尿病肾病是糖尿病常见的微血管并发症之一,胰高血糖素及其受体信号系统可能在它的发生、发展中发挥重要作用.其可能机制是通过cAMP、一氧化氮和前列腺素等诱导肾小球高滤过,通过增加DNA和蛋白质的合成诱导系膜细胞的增生、肥大,并可与肾素-血管紧张素系统(RAS)相互作用,最终引起肾小球损伤.胰高血糖素及其受体可作为治疗2型糖尿病及其肾脏并发症的靶点.     

Impact of high glucose and transforming growth factor-β on bioenergetic profiles in podocytes

Diabetic nephropathy is the most common cause of chronic renal failure in industrialized countries. Depletion of podocytes plays an important role in the progression of diabetic glomerulopathy. Various factors in the diabetic milieu lead to serious podocyte stress driving the cells toward cell cycle arrest (p27(Kip1)), hypertrophy, detachment, and apoptosis. Mitochondria are responsible for oxidative phosphorylation and energy supply in podocytes. Recent studies indicated that mitochondrial dysfunction is a key factor in diabetic nephropathy. In the present study, we investigated metabolic profiles of podocytes under diabetic conditions. We examined oxygen consumption rates (OCRs) and oxidative phosphorylation complex activities in murine podocytes. Cells were exposed to high glucose for 48 hours, cultured for 10 passages under high-glucose conditions (30 mmol/L), or incubated with transforming growth factor-β (5 ng/mL) for 24 hours. After prolonged exposure to high glucose, podocytes showed a significantly increased OCR at baseline and also a higher OCR after addition of oligomycin, indicating significant changes in mitochondrial energy metabolism. Higher OCRs after inhibition of respiration by rotenone also indicated changes in nonmitochondrial respiration. Podocytes stimulated with a proapoptotic concentration of transforming growth factor-β displayed similar bioenergetic profiles, even with decreased citrate synthase activity. In all tested conditions, we found a higher cellular nicotinamide adenine dinucleotide content and changes in activities of respiratory chain complexes. In summary, we provide for the first time evidence that key factors of the diabetic milieu induce changes in glucose metabolism and mitochondrial function in podocytes.