Epigallocatechin-3-gallate Synergistically Enhanced Arecoline-Induced Cytotoxicity by Redirecting Cycle Arrest to Apoptosis

Carcinogens, such as arecoline, play a crucial role in cancer progression and continuous gene mutations by generating reactive oxygen species (ROS). Antioxidants can reduce ROS levels and potentially prevent cancer progression but may paradoxically enhance the survival of cancer cells. This study investigated whether epigallocatechin-3-gallate (EGCG), an antioxidant from green tea, could resolve this paradox. Prostate cancer cells (PC-3 cell line) were cultured and treated with arecoline combined with NAC (N-acetylcysteine) or EGCG; the combined effects on intracellular ROS levels and cell viability were examined using the MTT and DCFDA assays, respectively. In addition, apoptosis, cell cycle, and protein expression were investigated using flow cytometry and western blot analysis. Our results showed that EGCG, similar to NAC (N-acetylcysteine), reduced the intracellular ROS levels, which were elevated by arecoline. Moreover, EGCG not only caused cell cycle arrest but also facilitated cell apoptosis in arecoline-treated cells in a synergistic manner. These were evidenced by elevated levels of cyclin B1 and p27, and increased fragmentation of procaspase-3, PARP, and DNA. Our findings highlight the potential use of EGCG for cancer prevention and therapy.

A Proteomics-Based Identification of the Biological Networks Mediating the Impact of Epigallocatechin-3-Gallate on Trophoblast Cell Migration and Invasion, with Potential Implications for Maternal and Fetal Health

Trophoblast migration and invasion play crucial roles in placental development. However, the effects of (-)-epigallocatechin-3-gallate (EGCG) on trophoblast cell functions remain largely unexplored. In this study, we investigated the impact of EGCG on the survival of trophoblast cells and employed a proteomics analysis to evaluate its influence on trophoblast cell migration and invasion. Be-Wo trophoblast cells were treated with EGCG, and a zone closure assay was conducted to assess the cell migration and invasion. Subsequently, a proteomics analysis was performed on the treated and control groups, followed by a bioinformatics analysis to evaluate the affected biological pathways and protein networks. A quantitative real-time PCR and Western blot analysis were carried out to validate the proteomics findings. Our results showed that EGCG significantly suppressed the trophoblast migration and invasion at a concentration not affecting cell survival. The proteomics analysis revealed notable differences in the protein expression between the EGCG-treated and control groups. Specifically, EGCG downregulated the signaling pathways related to EIF2, mTOR, and estrogen response, as well as the processes associated with the cytoskeleton, extracellular matrix, and protein translation. Conversely, EGCG upregulated the pathways linked to lipid degradation and oxidative metabolism. The quantitative PCR showed that EGCG modulated protein expression by regulating gene transcription, and the Western blot analysis confirmed its impact on cytoskeleton and extracellular matrix reorganization. These findings suggest EGCG may inhibit trophoblast migration and invasion through multiple signaling pathways, highlighting the potential risks associated with consuming EGCG-containing products during pregnancy. Future research should investigate the impact of EGCG intake on maternal and fetal proteoforms.

Erythrocyte degradation, metabolism, secretion, and communication with immune cells in the blood during sepsis: A review

Sepsis is a health issue that affects millions of people worldwide. It was assumed that erythrocytes were affected by sepsis. However, in recent years, a number of studies have shown that erythrocytes affect sepsis as well. When a pathogen invades the human body, it infects the blood and organs, causing infection and sepsis-related symptoms. Pathogens change the internal environment, increasing the levels of reactive oxygen species, influencing erythrocyte morphology, and causing erythrocyte death, i.e., eryptosis. Characteristics of eryptosis include cell shrinkage, membrane blebbing, and surface exposure of phosphatidylserine (PS). Eryptotic erythrocytes increase immune cell proliferation, and through PS, attract macrophages that remove the infected erythrocytes. Erythrocyte-degraded hemoglobin derivatives and heme deteriorate infection; however, they could also be metabolized to a series of derivatives. The result that erythrocytes play an anti-infection role during sepsis provides new perspectives for treatment. This review focuses on erythrocytes during pathogenic infection and sepsis.

Endovascular aortic repair is a cost-effective option for in-hospital patients with abdominal aortic aneurysm

BACKGROUND

To investigate the cost-effectiveness of endovascular aortic repair (EVAR) versus open aortic repair (OAR) for abdominal aortic aneurysm (AAA) using incremental costs per decreased in-hospital mortality rate gained through our patients' cohort.

METHODS

Medical records and healthcare costs of patients with AAA hospitalized between 2010 and 2015 were extracted from the National Health Insurance Research Database (NHIRD) of Taiwan. Multiple regression analysis was applied to adjust for confounding factors and to compare the differences in postoperative clinical outcomes between patients who received EVAR and OAR. The incremental cost-effectiveness ratio (ICER) of EVAR was determined based on the healthcare cost obtained from the analyzed data.

RESULTS

A total of 2803 AAA patients were identified (n = 559 with ruptured AAA and n = 2244 unruptured AAA). Patients with ruptured AAA who underwent EVAR compared with OAR patients had shorter hospital and intensive care unit (ICU) stays (all p < 0.05). For patients with unruptured AAA, those who received EVAR compared with OAR, the adjusted odds ratio (aOR) of postoperative complications and in-hospital mortality were 0.371 and 0.447 (all p < 0.05). The total direct surgical costs and medical expenses during hospitalization in all AAA patients were higher for the EVAR group; however, ICER was <1 per capita gross domestic product. Stratification by age groups further suggested that ICER for patients with unruptured AAA who received EVAR, compared with OAR, decreased with age.

CONCLUSION

Total direct medical costs were higher for AAA patients receiving EVAR regardless of rupture status; however, the cost is offset by lower odds of postoperative complications and in-hospital mortality. The observed decrease in ICER with age and EVAR use warrants further analysis. Our findings further validate the use of EVAR over OAR. These results provides supporting evidence for physicians and patients with AAA to inform shared decision making regarding endovascular or OAR options.

Early Screening of Risk for Multidrug-Resistant Organisms in the Emergency Department in Patients With Pneumonia and Early Septic Shock: Single-Center, Retrospective Cohort Study

OBJECTIVES

Pneumonia is the fourth leading cause of death globally, with rapid progression during sepsis. Multidrug-resistant organisms (MDROs) are becoming more common with some healthcare-associated pneumonia events. Early detection of MDRO risk improves the outcomes; however, MDROs risk in pneumonia with sepsis is unknown. This study investigated the disease outcomes of pneumonia with septic shock in patients admitted in the emergency department (ED) intensive care unit (ICU), a population with a high prevalence of MDROs, after early screening of MDROs risk.

METHODS

In this retrospective cohort study, patients with pneumonia and early septic shock (n = 533) admitted to the ED at the Taipei Tzu Chi Hospital from 2013 to 2019 were selected. The study population was divided into four subgroups after the MDROs risk and screening procedure were completed within 1 or 6 h of admission. ICU mortality and multidrug antibiotic therapy were compared.

RESULTS

The high-risk MDROs groups had higher percentage of P aeruginosa than the low-risk group. Furthermore, the appropriate ED first antibiotics were higher in the 1-h subgroup than in the 6-h subgroup of the high-risk MDROs group. In multivariate analysis, the 6-h high-risk MDROs group had an adjusted odds ratio of 7.191 (95% CI: 2.911-17.767, P < 0.001) and 2.917 (95% CI: 1.456-5.847, P = 0.003) for ICU mortality and multidrug therapy in the ICU, respectively, after adjusting for other confounding factors.

CONCLUSIONS

MDRO screening within 1 h is recommended following admission of patients with pneumonia and early septic shock in the ED, especially in areas with a high prevalence of MDROs.

Mechanisms of the antiplatelet and analgesic effects of dextromethorphan and its metabolites

Objective:

In the present study, we investigated the effects of dextromethorphan (DM) and its metabolites, including dextrorphan (LK2), 3-methoxymorphinan (LK3), and 3-hydroxymorphinan (LK4), on platelet aggregation in vitro and the inflammatory pain caused by carrageenan in rats, and their underlying mechanisms.

Materials and Methods:

Rabbit platelets were pretreated with DM or its metabolites to assess their effects on platelet aggregation and related target mediators. In addition, the analgesic activity and the underlying mechanisms of DM and LK3 were investigated in a carrageenan-evoked thermal hyperalgesia rat model.

Results:

The inhibitory potency of DM and its metabolites on platelet aggregation induced by arachidonic acid or collagen was LK3> DM > LK4>> LK2 as demonstrated by the half-maximal inhibitory concentration values. Moreover, the mechanisms of the antiplatelet effect of DM and LK3 may involve the inhibition of intracellular calcium mobilization, expression of platelet surface glycoprotein IIb/IIIa, the formation of thromboxane B₂, and elevation of platelet membrane fluidity. DM and LK3 also exhibited analgesic effects on carrageenan-evoked thermal hyperalgesia by suppressing the production of pro-inflammatory cytokines, nitric oxide, prostaglandin E₂, and neutrophil infiltration in inflammatory sites.

Conclusion:

DM and its metabolites, especially LK3, exhibit both antiplatelet and analgesic effects, and may, therefore, potentially ameliorate platelet hyperactivity and inflammatory-related diseases.

Staphylococcal phosphatidylinositol-specific phospholipase C potentiates lung injury via complement sensitisation

Staphylococcus aureus is frequently isolated from patients with community-acquired pneumonia and acute respiratory distress syndrome (ARDS). ARDS is associated with staphylococcal phosphatidylinositol-specific phospholipase C (PI-PLC); however, the role of PI-PLC in the pathogenesis and progression of ARDS remains unknown. Here, we showed that recombinant staphylococcal PI-PLC possesses enzyme activity that causes shedding of glycosylphosphatidylinositol-anchored CD55 and CD59 from human umbilical vein endothelial cell surfaces and triggers cell lysis via complement activity. Intranasal infection with PI-PLC-positive S. aureus resulted in greater neutrophil infiltration and increased pulmonary oedema compared with a plc-isogenic mutant. Although indistinguishable proinflammatory genes were induced, the wild-type strain activated higher levels of C5a in lung tissue accompanied by elevated albumin instillation and increased lactate dehydrogenase release in bronchoalveolar lavage fluid compared with the plc^- mutant. Following treatment with cobra venom factor to deplete complement, the wild-type strain with PI-PLC showed a reduced ability to trigger pulmonary permeability and tissue damage. PI-PLC-positive S. aureus induced the formation of membrane attack complex, mainly on type II pneumocytes, and reduced the level of CD55/CD59, indicating the importance of complement regulation in pulmonary injury. In conclusion, S. aureus PI-PLC sensitised tissue to complement activation leading to more severe tissue damage, increased pulmonary oedema, and ARDS progression.

Interleukin-18 promoter genotype is associated with the risk of nasopharyngeal carcinoma in Taiwan

Background

The incidence rate of nasopharyngeal carcinoma (NPC) has been documented to be high in Southeast Asia. Interleukin-18 (IL-18) is a multifunctional cytokine that augments interferon-γ production and acts as an important immunomediator in the development of several types of cancer.

Patients and methods

This case-control study evaluated the role of IL-18 in NPC at the DNA level by genotyping its promoter polymorphisms at positions -656, -607, and -137 in a Taiwanese population. A total of 176 patients with NPC and age- and gender-matched 352 noncancer controls were included in this study.

Results

The CC genotype of the IL-18-607 polymorphism was found to be associated with significantly decreased risks of NPC compared to the AA genotype (crude OR =0.50, 95% CI =0.29-0.84, P=0.0093). This significant difference persisted even in the dominant and recessive models. A significantly lower C allele frequency at position -607 was detected in the NPC group(41.8% vs 50.3%; OR =0.77; 95% CI =0.63-1.04, P=0.0089). Regarding IL-18-656 and -137 polymorphisms, there were no differential distributions of their genotypes between the NPC and control groups. After substratification of the subjects according to their smoking, alcohol consumption, and areca chewing status, the genotype distribution of the IL-18-607 polymorphism was found to be different only among nonsmokers between the NPC and control subgroups.

Conclusion

This study suggests that IL-18 plays an important role in the carcinogenesis of NPC in Taiwan and that the genotype-phenotype correlation of IL-18-607 polymorphism and its contribution to NPC need to be investigated further.

The contribution of interleukin-8 genotypes and expression to nasopharyngeal cancer susceptibility in Taiwan

The incidence rate of nasopharyngeal cancer (nasopharyngeal carcinoma [NPC]) is much higher in Southeast Asia than in western countries. Interleukin-8 (IL-8), a chemokine produced by macrophages, epithelial cells, airway smooth muscle cells, and endothelial cells, is an important immuno-mediator in the development and progression of many types of cancer. Genetic variations in IL-8 have been associated with the risks of NPC and other cancers. In the current study, we evaluated the role of IL-8 in NPC at the levels of DNA, RNA, and protein in a Taiwanese population. First, in a case-control study, 176 NPC patients and 352 cancer-free controls were genotyped, and the associations of IL-8 T - 251A, C + 781T, C + 1633T, and A + 2767T polymorphisms with NPC risk were evaluated. Second, the NPC tissue samples were assessed for their IL-8 mRNA and protein expression by real-time quantitative reverse transcription polymerase chain reaction (PCR) and Western blotting, respectively. Regarding the IL-8 promoter T - 251A, the TA and AA genotypes were associated with significantly decreased risks of NPC compared with the wild-type TT genotype (adjusted odds ratio = 0.61 and 0.52, 95% confidence interval = 0.47-0.93 and 0.37-0.91, P = .0415 and .0289, respectively). The mRNA and protein expression levels for NPC tissues revealed no significant associations among the 20 NPC samples with different genotypes. These findings suggest that IL-8 may play an important role in the carcinogenesis of NPC in Taiwan.

Cardiovascular Parameters Associated With Troponin I as Indicators for 14-Day Mortality in Patients With Septic Shock

BACKGROUND

Troponin I is better than other troponin isoforms for monitoring cardiocyte damage, and correlates with sepsis-related mortality. However, hemodynamic factors possibly interact with cardiac function to affect mortality in sepsis. Thus, this study used parameters from pulse-induced contour cardiac output (PiCCO) to investigate the possibility.

METHODS

Patients with troponin I tests and sequential organ failure assessment score ≥2 were selected and divided into survivors and nonsurvivors groups and blood troponin I levels between them were compared. Additionally, 65 patients with septic shock and PiCCO records were selected and divided into high cardiac function index (CFI) and low CFI groups and their cardiac function associated with troponin I levels was checked. Furthermore, the patients were classified into 4 subgroups based on CFI and another hemodynamical parameter of PiCCO for identifying if any interaction between CFI and the parameter existed.

RESULTS

High blood troponin I levels correlated with high mortality, and with low cardiac function (CFI < 4.5) alone or with low CFI combined with high stroke volume variation (SVV), but did not correlate with global end-diastolic index (GEDI), or systemic vascular resistance index. However, only the subgroup with low CFI and high SVV (CFI < 4.5 and SVV > 10) increased mortality.

CONCLUSIONS

Our data give an insight into interactions between cardiac and hemodynamic factors to cause cardiocyte damage and suggest that multiple factors (i.e., low CFI and high SVV) should be considered together to evaluate cardiocyte damage and mortality in sepsis.

Dual effects for lovastatin in anaplastic thyroid cancer: the pivotal effect of transketolase (TKT) on lovastatin and tumor proliferation

This study tested the hypothesis that the effects of lovastatin on anaplastic thyroid cancer cell growth are mediated by upregulation of transketolase (TKT) expression. The effects of lovastatin on TKT protein levels in ARO cells were determined using western blot and proteomic analyses. After treatment with lovastatin and oxythiamine, the in vitro and in vivo growth of ARO cells was determined using 3-(4,5-Dimethylthiazol-2-yl)-2,5- diphenyltetrazolium bromide (MTT) assays and tumor xenografts in nude mice. TKT protein expression in the ARO tumors was assessed using immunohistochemistry analysis. Proteomic analysis revealed that 25 µM lovastatin upregulated TKT expression. Co-treatment of ARO cells with 1 µM lovastatin + 1 µM oxythiamine increased TKT protein expression compared with control levels; however, no differences were observed with 10 µM lovastatin + 1 µM oxythiamine. Furthermore, treatment with either oxythiamine or lovastatin alone reduced ARO tumor expression of TKT, as well as decreased ARO cell proliferation in vitro and tumor growth in vivo. However, mice treated with both lovastatin and oxythiamine at the same time had tumor volumes similar to that of the untreated control group. We conclude that either lovastatin or oxythiamine reduced ARO cell growth; however, the combination of these drugs resulted in antagonism of ARO tumor growth.

Carbon Monoxide Inhibits Receptor Activator of NF-κB (RANKL)-Induced Osteoclastogenesis

BACKGROUND

Low concentrations of carbon monoxide (CO) have anti-inflammatory effects and can reduce bone erosion in a murine collagen-induced arthritis model. The objective of this study was to assess the effects of CO on receptor activator of NF-κB ligand (RANKL), one of the key stimulators of osteoclastogenesis.

METHODS

The in vivo effects of CO on RANKL expression were assessed in a collagen antibody-induced arthritis model in mice. Cell proliferation and apoptosis were assessed in the RAW246.7 cell line stimulated with RANKL and exposed to either air or CO. The number of tartrate resistant acid phosphatase (TRAP)-positive RAW246.7 cells was also examined after treatment with RANKL and the peroxisome proliferator-activated receptor gamma (PPARγ) agonist, Troglitazone.

RESULTS

CO reduced RANKL expression in the synovium of arthritic mice. Although CO slightly increased RAW246.7 cell proliferation, no differences in activated caspase 3 levels were detected. In addition, Troglitazone ameliorated the inhibitory effects of CO on RANKL-induced TRAP expression by RAW246.7 cells.

CONCLUSIONS

CO suppresses osteoclast differentiation by inhibiting the RANKL-induced activation of PPAR-γ. Given the role of the PPAR-γ/cFos (AP-1) pathway in regulating the transcription factor, NFATc1, the master regulator of osteoclastogenesis, further studies are warranted to explore CO in treating inflammatory bone disorders.

Significant Association of Cyclo-oxygenase 2 Genotypes with Upper Tract Urothelial Cancer

AIM

Reliable biomarkers are in urgent need for diagnosis, outcome prediction and treatment-effect monitoring for upper tract urothelial carcinomas (UTUC). Although up-regulation of cyclo-oxygenase 2 (COX2) is found in stroma and tumor cells in more than half of the patients with UTUC investigated, the genomic contribution of COX2 to UTUC has not been studied. The study aimed to evaluate the association of six polymorphic genotypes of COX2 with UTUC within a Taiwanese population.

MATERIALS AND METHODS

A total of 218 patients with UTUC and 580 healthy controls were genotyped for six COX2 polymorphisms, namely A-1195G, G-765C, T+8473C, intron 1, intron 5 and intron 6, and examined for their association with UTUC risk.

RESULTS

The distribution of genotypes of COX2 G-765C and intron 5 were significantly different between patient and control groups (p=0.0001 and 0.0016, respectively), while others were not (p>0.05). The haplotype analysis showed that compared to the GG/TT haplotype of COX2 G-765C/intron 5, those carrying GG/AT variants have a significantly increased risk of UTUC (odds ratio=4.83, 95% confidence interval=1.79-13.06), while those carrying CG/TT variants have a decreased risk (odds ratio=0.26, 95% confidence interval=0.14-0.49).

CONCLUSION

Our results suggest that individual and combined COX2 G-765C/intron 5 genotypes play a role in controlling COX2 expression and UTUC development.

Analysis of dermal papilla cell interactome using STRING database to profile the ex vivo hair growth inhibition effect of a vinca alkaloid drug, colchicine

Dermal papillae (DPs) control the formation of hair shafts. In clinical settings, colchicine (CLC) induces patients' hair shedding. Compared to the control, the ex vivo hair fiber elongation of organ cultured vibrissa hair follicles (HFs) declined significantly after seven days of CLC treatment. The cultured DP cells (DPCs) were used as the experimental model to study the influence of CLC on the protein dynamics of DPs. CLC could alter the morphology and down-regulate the expression of alkaline phosphatase (ALP), the marker of DPC activity, and induce IκBα phosphorylation of DPCs. The proteomic results showed that CLC modulated the expression patterns (fold>2) of 24 identified proteins, seven down-regulated and 17 up-regulated. Most of these proteins were presumably associated with protein turnover, metabolism, structure and signal transduction. Protein-protein interactions (PPI) among these proteins, established by Search Tool for the Retrieval of Interacting Genes/Proteins (STRING) database, revealed that they participate in protein metabolic process, translation, and energy production. Furthermore, ubiquitin C (UbC) was predicted to be the controlling hub, suggesting the involvement of ubiquitin-proteasome system in modulating the pathogenic effect of CLC on DPC.

Evaluation of the contribution of methylenetetrahydrofolate reductase genotypes to Taiwan breast cancer

The aim of the present study was to evaluate the effects of the genotypic polymorphisms in methylenetetrahydrofolate reductase (MTHFR) and its interaction with early-onset breast cancer risk in Taiwan. Two well-known polymorphic variants of MTHFR, C677T (rs1801133) and A1298C (rs1801131), were analyzed and their joint effects with individual age- and estrogen-related factors on breast cancer risk were discussed. In total, 1,232 patients with breast cancer and 1,232 healthy controls were genotyped by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). The MTHFR C677T genotype, but not the A1298C, was differently distributed between cancer and control groups. The T allele of MTHFR C677T was significantly more frequently found in controls than in patients with cancer. In addition, females carrying MTHFR C677T CT or TT genotypes had a higher odds ratio of 1.21 (95% confidence interval=1.03-1.42, p=1.85E-5) for breast cancer, especially before the age of 45.4 years (odds ratio=1.51 and 95% confidence interval=1.20-1.90). Our results indicate that MTHFR C677T T allele was associated with increased risk of breast cancer in Taiwan, especially in cases who were 45.4 old or younger and with earlier menarche age (<12.2 years).

Intratumoral decorin gene delivery by AAV vector inhibits brain glioblastomas and prolongs survival of animals by inducing cell differentiation

Glioblastoma multiforme (GBM) is the most malignant cancer in the central nervous system with poor clinical prognosis. In this study, we investigated the therapeutic effect of an anti-cancer protein, decorin, by delivering it into a xenograft U87MG glioma tumor in the brain of nude mice through an adeno-associated viral (AAV2) gene delivery system. Decorin expression from the AAV vector in vitro inhibited cultured U87MG cell growth by induction of cell differentiation. Intracranial injection of AAV-decorin vector to the glioma-bearing nude mice in vivo significantly suppressed brain tumor growth and prolonged survival when compared to control non-treated mice bearing the same U87MG tumors. Proteomics analysis on protein expression profiles in the U87MG glioma cells after AAV-mediated decorin gene transfer revealed up- and down-regulation of important proteins. Differentially expressed proteins between control and AAV-decorin-transduced cells were identified through MALDI-TOF MS and database mining. We found that a number of important proteins that are involved in apoptosis, transcription, chemotherapy resistance, mitosis, and fatty acid metabolism have been altered as a result of decorin overexpression. These findings offer valuable insight into the mechanisms of the anti-glioblastoma effects of decorin. In addition, AAV-mediated decorin gene delivery warrants further investigation as a potential therapeutic approach for brain tumors.

Urine annexin A1 as an index for glomerular injury in patients

BACKGROUND

We recently demonstrated high urine levels of annexin A1 (ANXA1) protein in a mouse Adriamycin-induced glomerulopathy (ADG) model.

OBJECTIVE

To establish ANXA1 as a potential biomarker for glomerular injury in patients.

METHODS

A time-course study in the mouse ADG model, followed by renal tissues and urine samples from patients with various types of glomerular disorders for ANXA1.

RESULTS

Urinary ANXA1 protein was (1) detectable in both the ADG model and in patients except those with minimal change disease (MCD); (2) positively correlated with renal lesions in patients; and (3) early detectable in diabetes patients with normoalbuminuria.

CONCLUSIONS

ANXA1 is a universal biomarker that is helpful in the early diagnosis, prognostic prediction, and outcome monitoring of glomerular injury. Measurement of urinary ANXA1 protein levels can help in differentiating MCD from other types of glomerular disorders.

The joint effect of hOGG1 genotype and smoking habit on endometriosis in Taiwan

This study has two aims: [1] to evaluate the association between hOGG1 genotypic polymorphism and endometriosis risk, and [2] to investigate the joint effects of hOGG1 genotype and smoking habit on endometriosis susceptibility in Taiwan. For this purpose, the well-known polymorphic variants of hOGG1, codon 326, was genotyped and analyzed of its association with the risk of endometriosis. In total, 153 patients with endometriosis and 636 non-endometriosis healthy controls were recruited and genotyped. The methodology for genotyping is polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Pearson's Chi-square test was performed to compare the distributions of the genotypes between case and control groups. The results showed that the hOGG1 codon 326 genotypes were not differently distributed between the endometriosis and non-endometriosis control groups in both genotypic (P = 0.6212) and allelic (P = 0.4006) frequency analysis. We have further analyzed the genotypic-smoking joint effects on endometriosis risk and found an obvious interaction between hOGG1 codon 326 genotypes and smoking status. The hOGG1 codon 326 genotypes were increased in endometriosis risk only in the smoker groups (P = 0.0061), but not in the non-chewer group (P = 0.0648). Our results provide the evidence that the hOGG1 codon 326 genotype may have a joint effect with smoking on the development of endometriosis.

Hyperpolarisation-activated cyclic nucleotide channel 4 (HCN4) involvement in Tourette's syndrome autoimmunity

OBJECTIVES

We previously found that antibodies in Tourette's syndrome (TS) patients' sera reacted with a 120 kDa protein from rat brain tissue. Here, we sought to identify this protein and determine if it was involved in TS pathogenesis.

METHODS

The 120 kDa protein was identified using immunoprecipitation, Western blotting, and mass spectrometry. ELISAs were used to quantify anti-120 kDa protein antibodies in serum of interest using samples from 32 TS patients, 47 patients with attention deficit hyperactivity disorder (ADHD) and 14 healthy controls. Involvement of the 120 kDa protein in TS was confirmed using co-localisation assays with GH3 cells. TS sera were micro-infused into SD rats' brain striatum and their stereotypical behaviours were monitored.

RESULTS

The brain protein was identified as hyperpolarisation-activated cyclic nucleotide channel 4 (HCN4). TS patients' sera contained significantly more anti-HCN4 antibodies than ADHD patient and control sera. After microinfusing TS serum, SD rats exhibited increased stereotyped tic behaviours, which were correlated with the amount of infused anti-HCN4 antibody.

CONCLUSIONS

Anti-HCN4 antibodies in the brain might contribute to the pathogenesis of tic symptoms in TS patients. However, further studies are needed to investigate the validity of this animal model of TS induced by microinfusing anti-HCN4 antibody.

The total synthesis of a ganglioside Hp-s1 analogue possessing neuritogenic activity by chemoselective activation glycosylation

The total synthesis of ganglioside 2, an analogue of the ganglioside Hp-s1 (1) which displays neuritogenic activity toward the rat pheochromocytoma cell line PC-12 cell in the presence of nerve growth factor (NGF) with an effect (34.0%) greater than that of the mammalian ganglioside GM 1 (25.4%), was accomplished by applying a chemoselective-activation glycosylation strategy. Moreover, we also demonstrate that the synthesized ganglioside 2 exhibited neuritogenic activity toward the human neuroblastoma cell line SH-SY5Y without the presence of NGF.

Epigallocatechin-3-gallate prevents lupus nephritis development in mice via enhancing the Nrf2 antioxidant pathway and inhibiting NLRP3 inflammasome activation

Patients with lupus nephritis show an impaired oxidative status and increased levels of interleukin (IL)-1β and IL-18, which are closely linked to inflammation and correlated with disease activity. Although epigallocatechin-3-gallate (EGCG), the major bioactive polyphenol present in green tea with antioxidant and free radical scavenging activities, has been reported to have anti-inflammatory effects by inhibiting nuclear factor-kappa B (NF-κB)-mediated inflammatory responses in vivo, its effectiveness for the treatment of lupus nephritis is still unknown. In the present study, 12-week-old New Zealand black/white (NZB/W) F1 lupus-prone mice were treated daily with EGCG by gavage until sacrificed at 34 weeks old for clinical, pathological, and mechanistic evaluation. We found that the administration (1) prevented proteinuria, renal function impairment, and severe renal lesions; (2) increased renal nuclear factor E2-related factor 2 (Nrf2) and glutathione peroxidase activity; (3) reduced renal oxidative stress, NF-κB activation, and NLRP3 mRNA/protein expression and protein levels of mature caspase-1, IL-1β, and IL-18; and (4) enhanced splenic regulatory T (Treg) cell activity. Our data clearly demonstrate that EGCG has prophylactic effects on lupus nephritis in these mice that are highly associated with its effects of enhancing the Nrf2 antioxidant signaling pathway, decreasing renal NLRP3 inflammasome activation, and increasing systemic Treg cell activity.

Rab23 plays a role in the pathophysiology of mesangial cells--a proteomic analysis

Rab23, a novel member of the Rab family of small GTPases, has recently been identified in mesangial cells (MCs). Although Rab23 levels in MCs are associated with glomerular nephropathies, the exact physiological and pathological roles of Rab23 in MCs are unknown. In the present study, its roles in MCs were explored by performing proteomics and systems biology analyses in MCs after knockdown or overexpression of Rab23. Knockdown of Rab23 was achieved by transfecting MCs with a plasmid expressing short hairpin RNA against Rab23, while overexpression of Rab23 was accomplished by transfection with the wild-type, dominant negative, and constitutively active Rab23 gene constructs. The effects of different levels of Rab23 activity on proteome of various biological pathways were investigated. Gel-based proteomic approaches and systems biology tools, respectively, were used to identify the Rab23-regulated proteins and the functional pathways. Proteomic analysis revealed the potential roles for Rab23 in multiple processes, including G-protein signal transduction, transcription modulation, RNA stabilization, protein synthesis and degradation, cytoskeleton reorganization, anti-oxidation and detoxification, circadian rhythm regulation and phagocytosis. Bioinformatics analyses showed that Rab23 impacts on multiple biological networks in MCs. These data may shed light on the roles of Rab23 in mesangiopathy or MC damage.

Isoelectric focusing management: an investigation for salt interference and an algorithm for optimization

Two-dimensional electrophoresis (2-DE) has evolved into a robust separation technique in proteomic research. However, one of the major challenges in 2-DE experiments, the reproducibility of the first dimensional electrophoresis (IEF), has remained unsolved. It is well-known that the quality of IEF experiments is significantly affected by the salt interference. Nevertheless, the interference mechanisms of salts in IEF have never been systematically investigated. In this study, we comprehensively investigated the interference effects in IEF due to various kinds of simple and buffer salts in protein samples. Two interference schemes were proposed accordingly to elucidate the interference mechanisms of salts in IEF. Furthermore, to increase the reproducibility of IEF, we proposed that conductivity measurement is a feasible method to assess the salt content of 2-DE samples and developed an algorithm to predict the optimal total volt-hours (Vh) required for protein focusing in IEF. The developed algorithm had been evaluated under various IEF conditions for a variety of 2-DE samples and proven to be a reliable guide. In sum, information disclosed in this study should be of use for increasing the reproducibility and thus the applicability of 2-DE in current proteomics.

Effects of fungal statins on high-glucose-induced mouse mesangial cell hypocontractility may involve filamentous actin, t-complex polypeptide 1 subunit beta, and glucose regulated protein 78

Glomerular hyperfiltration is associated with mesangial cell hypocontractility. How 3-hydroxy-3-methylglutaryl-coenzyme A reductase inhibitors (statins) influence mesangial cell contraction is unclear. We investigated the effect of statins on mesangial cell hypocontractility and identified candidate proteins and filamentous/globular (F/G)-actin involved in this process. A high-glucose-induced mouse mesangial cell hypocontractility model was treated with fungal statins, simvastatin (Sim), lovastatin (Lov), and pravastatin (Pra). The optimum statin dose was determined by an 3-(4,5-Dimethylthiazol-2-Yl)-2,5-Diphenyltetrazolium Bromide (MTT) assay and then applied to a cell model. A 2-dimensional gel/matrix-assisted laser desorption/ionization time-of-flight mass spectrometer analysis was used to evaluate protein expression cells incubated in the presence of a normal level of glucose (N), a high level of glucose (H), and a high level of glucose plus Sim (H + S). Candidate proteins were analyzed. Finally, the ratio of F/G actin in groups N, H, and H+S was evaluated. The MTT assay showed that Sim and Lov exerted dose- and time-related inhibition of proliferation of mesangial cells at N, but Pra had no effect. The optimum doses selected for Sim was 1 microM and for Lov was 3 microM, which were 1 increment before significant proliferation inhibition. Both doses reversed cell hypocontractility significantly, but Sim was chosen for further proteomic and F/G actin analyses. Proteomic analysis of groups N, H, and H + S showed that 18 proteins were involved in hypocontractility. These proteins were grouped and analyzed based on their known functions. Two selected proteins, TCP-1beta and GRP78, that were upregulated and downregulated, respectively, were confirmed by Western blot and immunohistochemistry. In regard to the F/G actin, group H had a significantly lower ratio than that of group N, and group H + S returned to a level similar to that of group N. In conclusion, Sim and Lov both seem to reverse mesangial cell hypocontractility. The process of Sim reversal of mesangial cell hypocontractility may involve F-actin, TCP-1beta, and GRP78.

Neurotrophic effects of tianeptine on hippocampal neurons: a proteomic approach

Tianeptine, an atypical tricyclic antidepressant with unique characteristics, can improve memory and prevent stress-induced hippocampal damage. It has neuroplastic and neurotrophic effects on hippocampal neurons and can prevent dendritic atrophy of the hippocampus in certain pathological conditions. To obtain a better understanding of the underlying mechanisms, we performed a proteomic analysis on tianeptine-treated hippocampal neurons. Primary hippocampal neurons were prepared from fetal Sprague-Dawley rats, eliminating glia cells by addition of cytosine beta-D-arabinofuranoside at day 2 in vitro (DIV2). The neurons were treated with tianeptine (10 microg/mL) or vehicle at DIV3, then harvested at DIV4 or DIV9 for immunocytochemical analysis of, respectively, neurite outgrowth or synapse formation. A proteomics analysis was performed on DIV4 neurons and the data were confirmed by Western blot analysis. Using specific markers, we demonstrated that tianeptine can augment neurite growth and promote synaptic contacts in cultured hippocampal neurons. The proteomics analysis identified 11 differentially expressed proteins, with roles in neurite growth, metabolism of neurotrophic substances, synaptogenesis, and synaptic activity homeostasis. The data shed light on the mechanisms underlying the neurotrophic effect of tianeptine observed in both animal studies and the clinic.

Motility and protein phosphorylation in healthy and asthenozoospermic sperm

The majority of male infertility results from poor sperm motility. A direct link between altered protein phosphorylation and aberrant sperm motility has not been established. To address this issue, sperm samples obtained from 20 donors with healthy sperm and 20 donors with aberrantly motile sperm were subjected to computer assisted semen analysis (CASA), proteomic analysis, Western blot, and immunofluorescent staining. Proteomic analysis identified 12 protein spots as having differential phosphorylation, including gamma-tubulin complex associated protein 2 (GCP2). Western blot and immunofluorescence demonstrated differential expression of gamma-tubulin between healthy and aberrantly motile sperm. In conclusion, hypophosphorylated proteins and reduced expression of gamma-tubulin may be associated with low motility sperm.

A comprehensive evaluation of imidazole-zinc reverse stain for current proteomic researches

In this paper, we comprehensively evaluated the capability of imidazole-zinc reverse stain (ZN) in comparative proteomics. Three commonly used protein gel staining methods, including silver (SN), SYPRO Ruby (SR), and CB stain were investigated alongside for comparison purpose. A transparency scanning procedure, which may deliver more even and contrasting gel images, was found best for documenting ZN stained gels. Our results showed that ZN was more sensitive than SN, SR, and CB. It may reveal as few as 1.8 ng of proteins in a gel. Moreover, ZN was found to provide a linear dynamic range of staining for revealing proteins up to 140 ng, and show an insignificant staining preference. To analyze a ZN stained 2-D gel image that generally comprises an apparent but even background, the Melanie 4 software was found more suitable than others. Furthermore, ZN demonstrated an equivalent or better MS compatibility than the other three staining methods. Intense and comprehensive MS profiles were frequently observed for ZN stained gel spots. Approximate two-third of ZN stained gel spots were successfully identified for protein identities. Taken together, our results suggest that the prompt, cost effective and versatile ZN is well suited for current proteomic researches.

Mesangial cells of lupus-prone mice are sensitive to chemokine production

Infectious antigens may be triggers for the exacerbation of systemic lupus erythematosus. The underlying mechanism causing acceleration and exacerbation of lupus nephritis (LN) is largely unknown. Bacterial lipopolysaccharide (LPS) is capable of inducing an accelerated model of LN in NZB/W mice, featuring diffuse proliferation of glomerular resident cells. We hypothesized that mesangial cells (MCs) from LN subjects are more responsive to LPS than normal subjects. Cultured primary NZB/W and DBA/W (nonautoimmune disease-prone strain with MHC class II molecules identical to those of NZB/W) MCs were used. Monocyte chemoattractant protein-1 (MCP-1) and osteopontin (OPN) expressions either in the baseline (normal culture) condition or in the presence of LPS were evaluated by real-time PCR, ELISA, or western blot analysis. NF-κB was detected by ELISA, electrophoresis mobility-shift assay, and immunofluorescence. First, either in the baseline condition or in the presence of LPS, NZB/W MCs produced significantly higher levels of MCP-1 and OPN than the DBA/W MC controls. Second, NZB/W MCs expressed significantly higher levels of Toll-like receptor 4, myeloid differentiation factor 88, and NF-κB than the DBA/W MC controls, both receiving exactly the same LPS treatment. In conclusion, NZB/W MCs are significantly more sensitive than their normal control DBA/W MCs in producing both MCP-1 and OPN. With LPS treatment, the significantly elevated levels of both chemokines produced by NZB/W MCs are more likely due to a significantly greater activation of the Toll-like receptor 4-myeloid differentiation factor 88-associated NF-κB pathway. The observed abnormal molecular events provide an intrarenal pathogenic pathway involved in an accelerated type of LN, which is potentially infection triggered.

Osteopontin as an injury marker expressing in epithelial hyperplasia lesions helpful in prognosis of focal segmental glomerulosclerosis

Focal segmental glomerulosclerosis (FSGS) is characterized by typical sclerosis but also shows other non-sclerotic lesions that provide prognostic informations. The glomerular epithelial hyperplasia lesion (EPHL) that develops earlier than the sclerotic lesions is a key determinant of progression of FSGS. However, the relationship among EPHL, glomeular sclerosis, and macrophage infiltration in FSGS is unclear, and the EPHL-associated markers helpful for prognosis of FSGS have still not been completely identified. Here, we performed clinicopathologic, immunochemical, and molecular analyses to examine whether osteopontin (OPN), a macrophage chemokine, is an injury marker of EPHLs correlating with glomerular sclerosis and macrophage mobilization. First, the FSGS model was induced in Balb/c mice by a single injection of adriamycin, and consecutive sclerosis changes were evaluated. In parallel, we used reverse transcription-polymerase chain reaction and Western blot analyses to determine levels of OPN in isolated glomeruli and urine, respectively. Immunohistochemistry was applied to assess the OPN expression in EPHLs and macrophage infiltration around the glomeruli. Our results showed that, within glomeruli, OPN expressed restrictedly within EPHL; the OPN mRNA and protein of glomeruli increased on day 11, correlating well with the early EPHL, and following sclerosis and macrophage infiltration. In addition, immunohistochemistry (IHC) staining of OPN greatly highlighted early glomerular EPHLs, helping microscopic identification of EPHLs. We propose that the OPN expression in EPHLs could contribute to the progression of FSGS by recruiting macrophage toward the compromised glomeruli. Detection of OPN in glomeruli and urine could be helpful in prognosis of FSGS.

Urinary proteome and potential biomarkers associated with serial pathogenesis steps of focal segmental glomerulosclerosis

BACKGROUND

Focal segmental glomerulosclerosis (FSGS) is a chronic nephropathy showing characteristic glomerular sclerosis. So far, the diagnosis and prognosis of FSGS rely mainly on the invasive biopsy. Searching for potential FSGS-associated urinary biomarkers representing pre-sclerotic and serial sclerotic stages of FSGS could be helpful to the non-invasive diagnosis and prognosis of FSGS.

METHODS

In the present study, we used a 2D gel-based proteomic approach to identify urinary proteins at pre-sclerotic and different sclerotic stages of an FSGS mouse model in order to find FSGS-related urinary proteins. The FSGS mouse model was established in Balb/c mice by a single injection of adriamycin, and disease severity was monitored by renal biological parameters and histopathological features. Urine was collected on days 0, 4, 7, 11, 15 and 20, and subjected to two-dimensional electrophoresis (2-DE) analysis. Proteins were identified by matrix-assisted laser desorption ionization/time of flight mass spectrometry (MALDI-TOF MS) and a protein database search. Some of the identified proteins were confirmed by western blot analysis.

RESULTS

We identified 37 urinary proteins showing characteristic patterns of dynamic changes along the disease course of FSGS. Early urinary proteins appearing before glomerular sclerosis were noticed. Importantly, 11 urine proteins are novel to FSGS and have known functions highly associated with different pathogenetic steps of the disease, including haemodynamic disturbance, podocyte apoptosis, ECM-protein deposition and glomerular sclerosis.

CONCLUSIONS

Some urinary proteins appearing earlier than glomerular sclerosis could serve as potential early diagnostic biomarkers. The proteins with the pathogenic roles could serve as potential non-invasive prognostic markers of FSGS, and give an insight into pathogenic mechanisms of this sclerosis disease.

Smad7 gene therapy ameliorates an autoimmune crescentic glomerulonephritis in mice

Autoimmune crescentic glomerulonephritis is characterized by severe immune response with glomerular crescentic formation and fibrosis in the kidney. Recent studies indicate that overexpression of renal Smad7 attenuates both renal fibrosis and inflammation in rat remnant kidney. However, little attention has been paid to the potential role of TGF-beta/Smad signaling in autoimmune kidney disease. This study tested the hypothesis that blocking TGF-beta signaling by overexpression of Smad7 may have a therapeutic effect in a mouse model of autoimmune crescentic glomerulonephritis that was induced in C57BL/6 x DBA/2J F1 hybrid mice by giving DBA/2J donor lymphocytes. Smad7 gene was transfected into the kidney using the ultrasound-microbubble-mediated system. Results showed that overexpression of Smad7 blocked both renal fibrosis and inflammatory pathways in terms of Smad2/3 and NF-kappaB activation (P < 0.01), thereby inhibiting alpha-smooth muscle actin; collagen I, III, and IV accumulation; and expression of inflammatory cytokines (IL-1beta and IL-6), adhesion molecule/chemokine (intercellular adhesion molecule-1, monocyte chemoattractant protein-1), and inducible nitric oxide synthase (all P < 0.01). Leukocyte infiltration (CD4(+) cells and macrophages) was also suppressed (P < 0.005). Severe histologic damage (glomerular crescent formation and tubulointerstitial injury) and functional injury including proteinuria were significantly improved (all P < 0.05). This study provides important evidence that overexpression of Smad7 may have therapeutic potential for autoimmune kidney disease.

Proteomic analysis of spinal protein expression in rats exposed to repeated intrathecal morphine injection

Repeated administration of morphine for treating severe chronic pain may lead to neuroadaptive changes in the spinal cord that are thought to underlie molecular mechanisms of the development of morphine tolerance and physical dependence. Here, we employed a 2-D gel-based proteomic technique to detect the global changes of the spinal cord protein expression in rats that had developed morphine tolerance. Morphine tolerance at the spinal cord level was induced by repeated intrathecal injections of morphine (20 microg/10 microL) twice daily for 5 days and evaluated by measurements of paw withdrawal latencies and maximal possible analgesic effect at day 5. After behavioral tests, the lumbar enlargement segments of spinal cord were harvested and proteins resolved by 2-DE. We found that eight proteins were significantly up-regulated or down-regulated in spinal cord after morphine tolerance development, including proteins involved in targeting and trafficking of the glutamate receptors and opioid receptors, proteins involved in oxidative stress, and cytoskeletal proteins, some of which were confirmed by Western blot analysis. Morphine-induced expressional changes of these proteins in the spinal cord might be involved in the central mechanisms that underlie the development of morphine tolerance. It is very likely that these identified proteins may serve as potential molecular targets for prevention of the development of morphine tolerance and physical dependence.

Fibronectin in blood invokes the development of focal segmental glomerulosclerosis in mouse model

BACKGROUND

Focal segmental glomerulosclerosis (FSGS) is caused by gradual deposition of extracellular matrix proteins, one of which, fibronectin (FN) is critical for sclerosis development. The origin of the FN deposited at an early stage of FSGS is still unclear.

METHODS

For investigating the origin of FN, the onset of increases in FN levels in the serum, glomeruli and urine were studied in a mouse model induced by adriamycin and compared with the time-course of development of glomerulosclerosis and expression of FN mRNA.

RESULTS

In the FSGS mice, serum FN levels were significantly increased as early as the onset of proteinuria on day 4 (7.26 +/- 0.37 mg/ml compared with 5.58 +/- 0.76 mg/ml in normal controls, P < 0.05). This was followed by an increase in glomerular deposition of FN protein on day 7 (FN/actin ratio, 0.216 +/- 0.003 compared with 0.039 +/- 0.009 in normal controls, P < 0.05). Glomerular m-RNA expression was also significantly elevated on day 7, but the locally synthesized FN did not show any increase until day 15. A significant increase in urinary FN protein and focal glomerulosclerosis was seen on day 11.

CONCLUSIONS

We infer that FN in blood acts as an initiator of the development of FSGS in this mouse model. In addition, serum and urine FN proteins could serve as useful biomarkers for monitoring the progression of FSGS.

Monoamine levels in the nucleus accumbens correlate with male sexual behavior in middle-aged rats

The correlation between monoamine levels in the nucleus accumbens (NAcc) and male sexual behavior was studied in middle-aged rats. Male rats (18-19months) were assigned to three groups: (1) Group MIE consisted of rats showing mounts, intromissions, and ejaculations; (2) Group MI was composed of rats showing mounts and intromissions, but no ejaculation; and (3) Group NC were non-copulators showing no sexual behavior. Young adult rats (4-5months), displaying complete copulatory behavior, were used as the control group. Levels of dopamine (DA), serotonin, and norepinephrine and their metabolites in the NAcc were measured by high-pressure liquid chromatography with electrochemical detection. No difference was seen in DA levels between MIE rats and young controls, whereas DA levels in NC rats were significantly lower than those in both MIE and MI rats. Serotonin levels in NC rats were significantly higher than those in MIE and MI rats. Conversely, norepinephrine levels in NC rats were lower than those in MIE rats. These results suggest that monoamine levels in the NAcc correlate with sexual performance in male rats and that changes in NAcc monoamine levels might affect male sexual behavior in middle-aged rats.

Calcium-binding proteins annexin A2 and S100A6 are sensors of tubular injury and recovery in acute renal failure

BACKGROUND

Rise in cellular calcium is associated with acute tubular necrosis, the most common cause of acute renal failure (ARF). The mechanisms that calcium signaling induce in the quiescent tubular cells to proliferate and differentiate during acute tubular necrosis have not been elucidated.

METHODS

Acute tubular necrosis induced in mice by single intravenous injection of uranyl nitrate and examined after 1, 3, 7, and 14 days. Renal function was monitored and kidneys were evaluated by histology, immunohistochemistry, Western blotting, in situ hybridization, and real-time reverse transcription-polymerase chain reaction (RT-PCR). Models of folic acid induced-ARF and ischemic/reperfusion (I/R) injury were similarly investigated.

RESULTS

Analysis of mRNA expression of intracellular calcium and phospholipid-binding proteins demonstrated selective expression of S100A6 and Annexin A2 (Anxa2) in the renal cortex with marked elevation on day 3, and gradually decline on day 7 and further attenuation on day 14. Similarly, the expression of both proteins, as demonstrated by immunohistochemistry and Western blot analysis, was increased and reached the peak level on day 7 and then gradually declined by day 14. Vimentin, a marker of dedifferentiated cells, was highly expressed during the recovery phase. Combined in situ hybridization immunohistochemistry revealed colocalization of both S100A6 and Anxa2 with proliferating cell nuclear antigen (PCNA). The universality of this phenomenon was confirmed in two other mouse acute tubular necrosis models, the ischemic-reperfusion injury and folic acid-induced ARF.

CONCLUSION

Collectively, these findings demonstrate that S100A6 and Anxa2 expression, initiated in response to tubular injury, persist in parallel throughout the recovery process of tubular cells in acute renal failure.

Glomerular crescent-related biomarkers in a murine model of chronic graft versus host disease

BACKGROUND

We examined the alterations in gene expression associated with the development of crescentic glomerulonephritis in murine chronic graft-versus-host disease, a model for human systemic lupus erythematosus.

METHODS

The disease was induced in (C57BL/6 x DBA/2) F(1) hybrids by injection of DBA/2 lymphocytes leading to deposition of auto-antibodies in the glomeruli, and a lupus type of nephritis morphologically. After extensive crescent formation at week 9 of disease, cDNA microarray analysis was performed and highly expressed genes were evaluated as molecular markers by real-time reverse transcription-polymerase chain reaction (RT-PCR), in situ hybridization, immunohistochemistry and immunoassay of urine proteins.

RESULTS

Six genes, secreted acidic cysteine-rich glycoprotein (Sparc), thymosin beta 10 (Tmsb10), S100 calcium-binding protein A6 (S100a6), annexin A2 (Anxa2), osteopontin (OPN) and lipocalin 2 (Lcn2), were quantified by real-time RT-PCR in laser microdissected glomeruli in a time course manner. Sparc was detected early before the onset of proteinuria and continued to increase throughout the course of the disease. The expression of Tmsb10, S100a6 and Anxa2 coincided with heavy proteinuria. By week 9, OPN and Lcn2 were highly expressed. The expression of proteins encoded by these genes was predominant in the glomerular crescent. The protein levels of Sparc, OPN and Lcn2 in urine were significantly elevated.

CONCLUSIONS

These findings implicate these six genes in the development of glomerular crescents. More importantly, detection of Sparc, OPN and Lcn2 in urine may mean that these molecules could serve as important biomarkers for non-invasive diagnosis of glomerular crescents.

Effects of incisor-cutting on muricidal behavior induced by olfactory bulbectomy in rats

Muricidal behavior in rats is composed of two main components, attacking and killing performance. Since a large number of mice could be killed by rats during behavioral experiments, research has been limited in the past decade possibly because of ethical considerations. In preliminary studies, we found that the rat incisors play a key role in muricidal behavior in rats, so, in the present study, we cut off the incisors and assessed the following parameters of muricidal behavior: attack latency, first attack site, lethal attack site, attack frequency, total attack duration and mean attack duration. If after incisor-cutting (IC) rats still tried to demonstrate muricidal activity, but failed to kill the mouse, this would be an ideal model for studying the mechanisms of muricidal behavior. Since muricide can be induced in rats by olfactory bulbectomy (OBX), young adult male Wistar rats with OBX displaying muricidal behavior were tested for muricidal activity 4 h after IC, then every 24 h for 3 days. At 4 and 28 h after IC, only 9% and 36% of rats killed mice, but these values rose to 73% and 82% 52 and 76 h after IC, respectively. At 4, 28 and 52 h after IC, there was no significant difference in attack latency, first attack site, lethal attack site or mean attack duration between IC-treated rats (both killers and nonkillers) and sham-operated controls, while the attack frequency was obviously increased in IC nonkiller rats, and a significantly longer total attack duration was seen in both IC killer and nonkiller rats compared to controls. Since IC treatment increases attack frequency and prolongs the total attack duration without affecting other basic components of muricidal behavior in rats, these results suggest that the killer rats treated with IC may provide a suitable model for research on muricidal behavior.

Proteomic analysis of proteins in PC12 cells before and after treatment with nerve growth factor: increased levels of a 43-kDa chromogranin B-derived fragment during neuronal differentiation

Proteomic analysis is an important approach to characterizing the proteome and studying protein function in the post-genomic era. It is also a powerful screening method for detecting unexpected alterations in protein expression that may be missed by conventional biochemical techniques. The aim of this study was to perform a preliminary proteomic analysis of PC12 cells in order to investigate the effect of nerve growth factor (NGF) on protein expression in PC12 cells during neurite outgrowth. PC12 cell proteins were separated by two-dimensional electrophoresis (2DE) and visualized by silver staining, then certain proteins were identified by N-terminal amino acid microsequencing and a homology search of a protein sequence database. Over 400 proteins were detected, 10% of which showed a significant (greater than 30%) increase or decrease in expression during NGF-induced neuronal differentiation. Seven proteins in the 2DE map were identified; the levels of five of these were unaffected by NGF treatment, whereas the levels of the other two, beta-tubulin and a novel 43-kDa chromogranin B-derived fragment, were significantly increased by more than 30 and 200%, respectively. Our results suggest that chromogranin B processing is enhanced in PC12 cells during NGF-induced neuronal differentiation. In addition, since this increase in the levels of the chromogranin B-derived fragment was specifically blocked by PD98059, we suggest that the increased processing can be ascribed to activation of the MAP kinase pathway, and that the 43-kDa chromogranin B-derived fragment can serve as a new marker of neuronal differentiation for proteomic studies.

Early metabolic inhibition-induced intracellular sodium and calcium increase in rat cerebellar granule cells

1. Possible mechanisms responsible for the increases in intracellular calcium ([Ca2+]i) and sodium ([Na+]i) levels seen during metabolic inhibition were investigated by continuous [Ca2+]i and [Na+]i measurement in cultured rat cerebellar granule cells. An initial small mitochondrial Ca2+ release was seen, followed by a large influx of extracellular Ca2+. A large influx of extracellular Na+ was also seen. 2. The large [Ca2+]i increase was not due to opening of voltage-dependent or voltage-independent calcium channels, activation of NMDA/non-NMDA channels, activation of the Na+i-Ca2+o exchanger, or inability of plasmalemmal Ca2+-ATPase to extrude, or mitochondria to take up, calcium. 3. The large [Na+]i increase was not due to activation of the TTX-sensitive Na+ channel, the Na+i-Ca2+o exchanger, the Na+-H+ exchanger, or the Na+-K+-2Cl- cotransporter, or an inability of Na+-K+-ATPase to extrude the intracellular sodium. 4. Phospholipase A2 (PLA2) activation may be involved in the large influx, since both were completely inhibited by PLA2 inhibitors. Moreover, melittin (a PLA2 activator) or lysophosphatidylcholine or arachidonic acid (both PLA2 activation products) caused similar responses. Inhibition of PLA2 activity may help prevent the influx of these ions that may result in serious brain injury and oedema during hypoxia/ischaemia.

Recovery of high potassium-evoked dopamine release after depolarization challenge in the striatum of young and old male rats

The aim of this study was to assess the recovery of high potassium-evoked dopamine (DA) release after depolarization challenge in young (3-4 months) and old (21-25 months) male Wistar rats. Recovery of DA release was evaluated by comparison of the peak responses of DA release induced by two serial high potassium stimulations. Concentric microdialysis probes were stereotaxically implanted in the lateral striatum of rats, and microdialysis was commenced 24 h after surgery. Using a low flow rate of perfusion (1 microl/min), all rats received 2 x 20 min infusions of 100 mM potassium solution separated by either 60 or 140 min. No difference in the basal DA concentration or the potassium-evoked DA release or its recovery was seen between the two groups. Our results suggest that the vesicular DA store recovers rapidly after high potassium challenge in both young and old rats.