Clinical Study of SCIN Expression and Dromoter Methylation in Patients with Chronic Myeloid Leukemia / 中国实验血液学杂志

OBJECTIVE@#To investigate the clinical significance of SCIN gene expression and promoter methylation in patients with chronic myeloid leukemia (CML).@*METHODS@#Real-time quantitative PCR was used to detect the expression level of SCIN in mononucleatr cells of bone marrow samples from 64 CML patients and 37 controls. The methylation levels of SCIN promoter in 65 patients with CML and 29 controls were detected by real-time quantitative methylation-specific PCR and bisulfite sequencing PCR.@*RESULTS@#The expression level of SCIN in CML patients was significantly down-regulated (P＜0.05), compared with the control group. The down-regulation rate of SCIN expression in CML patients at chronic phase, accelerated phase and blast crisis was 61%, 67% and 75%, respectively. Spearman correlation analysis showed that the expression level of SCIN negatively correlated with the transcript level of BCR-ABL1 (R=-0.315, P＜0.05). However, there was no significant difference in clinical parameters such as sex, age, white blood cell count, hemoglobin level, platelet count, chromosome, CML staging and BCL-ABL1 transcript level between low and high SCIN expression groups of CML patients (P＞0.05). No significant difference in methylation of SCIN promoter between CML patients and controls, and no correlation between SCIN expression and promoter methylation were observed (P＞0.05).@*CONCLUSION@#The SCIN expression is down-regulated in CML patients, which may relate with the pathogenesis that is, BCR-ABL1 fusion gene induces CML tumorigenesis. The down-regulation of SCIN expression may relate with the progression of CML.

Identification of 10 Candidate Biomarkers Distinguishing Tuberculous and Malignant Pleural Fluid by Proteomic Methods

PURPOSE: Pleural effusion, an accumulation of fluid in the pleural space, usually occurs in patients when the rate of fluid formation exceeds the rate of fluid removal. The differential diagnosis of tuberculous pleurisy and malignant pleural effusion is a difficult task in high tuberculous prevalence areas. The aim of the present study was to identify novel biomarkers for the diagnosis of pleural fluid using proteomics technology. MATERIALS AND METHODS: We used samples from five patients with transudative pleural effusions for internal standard, five patients with tuberculous pleurisy, and the same numbers of patients having malignant effusions were enrolled in the study. We analyzed the proteins in pleural fluid from patients using a technique that combined two-dimensional liquid-phase electrophoresis and matrix assisted laser desorption/ionization-time of flight-mass spectrometry. RESULTS: We identified a total of 10 proteins with statistical significance. Among 10 proteins, trasthyretin, haptoglobin, metastasis-associated protein 1, t-complex protein 1, and fibroblast growth factor-binding protein 1 were related with malignant pleural effusions and human ceruloplasmin, lysozyme precursor, gelsolin, clusterin C complement lysis inhibitor, and peroxirexdoxin 3 were expressed several times or more in tuberculous pleural effusions. CONCLUSION: Highly expressed proteins in malignant pleural effusion were associated with carcinogenesis and cell growth, and proteins associated with tuberculous pleural effusion played a role in the response to inflammation and fibrosis. These findings will aid in the development of novel diagnostic tools for tuberculous pleurisy and malignant pleural effusion of lung cancer.

Prognostic significance of plasma gelsolin in severe burn patients with sepsis / 中华烧伤杂志

<p><b>OBJECTIVE</b>To investigate the changes in plasma gelsolin (pGSN) levels in severe burn patients with sepsis, and to evaluate the prognosis of patients when combined with other related clinical indexes.</p><p><b>METHODS</b>Sixty-five severe burn patients with sepsis hospitalized from June 2013 to June 2015 conforming to the study criteria were divided into death group (n=24) and survival group (n=41) according to the clinical outcome on post sepsis diagnosis day (PSD) 28. The pGSN levels of patients were determined on PSD 1, 3, 7, and 14 with double antibody sandwich enzyme-linked immunosorbent assay. The serum level of C-reactive protein (CRP), serum level of procalcitonin, lactate level of arterial blood, Acute Physiology and Chronic Health Evaluation (APACHE) II score, and Sequential Organ Failure Assessment (SOFA) score were determined or recorded on PSD 1. Data were processed with repeated measurement analysis of variance, t test, and chi-square test. On PSD 1, the pGSN level, serum level of CRP, serum level of procalcitonin, lactate level of arterial blood, APACHE II score, and SOFA score of 65 patients were collected to screen the independent risk factors related to death with single factor and multi-factor Logistic regression analysis. Receiver operating characteristic (ROC) curves of the independent risk factors related to death were plotted to evaluate the predictive power for death in 65 patients.</p><p><b>RESULTS</b>(1) The pGSN levels of patients in death group on PSD 1, 3, 7, and 14 were respectively (146±44), (85±24), (28±7), and (19±4) mg/L, obviously lower than those in survival group [(287±82), (179±51), (196±56), and (249±67) mg/L, with t values from 1.735 to 4.304, P<0.05 or P<0.01]. (2) The serum level of CRP, serum level of procalcitonin, lactate level of arterial blood, APACHE II score, and SOFA score of patients in death group on PSD 1 were respectively (56±7) mg/L, (12.54±0.82) μg/L, (2.74±0.27) mmol/L, (24.3±2.4) points, and (11.43±0.57) points, significantly higher than those in survival group [(35±4) mg/L, (2.38±0.16) μg/L, (1.83±0.12) mmol/L, (15.0±1.5) points, and (7.22±0.23) points, with t values from 1.902 to 3.883, P<0.05 or P<0.01]. (3) Multi-factor Logistic regression analysis showed that the pGSN level (odds ratio: 6.83, 95% confidence interval: 4.33-10.25, P<0.01) and APACHE II score (odds ratio: 5.27, 95% confidence interval: 2.28-9.16, P<0.01) were the independent risk factors related to death in 65 patients on PSD 1. (4) The total areas under the ROC curves of pGSN level and APACHE II score for predicting death of 65 patients on PSD 1 were respectively 0.89 and 0.86, and 142 mg/L and 21 points were respectively chosen as the optimal threshold values, with sensitivity of 87% and 83% and specificity of 86% and 89%.</p><p><b>CONCLUSIONS</b>For severe burn patients with sepsis, lowering of pGSN level and elevation of APACHE II score are obviously correlated with increase in case fatality rates. Monitoring the dynamic changes in pGSN level and APACHE II score during the early stage may be useful to predict the prognosis of severe burn patients with sepsis.</p>

The First Korean Family With Hereditary Gelsolin Amyloidosis Caused by p.D214Y Mutation in the GSN Gene

Hereditary gelsolin amyloidosis (HGA) is an autosomal dominant hereditary disease characterized by corneal lattice dystrophy, peripheral neuropathy, and cutis laxa. So far, no Korean patients with HGA have been reported. A 58-yr-old man presented with involuntary facial twitching, progressive bilateral facial weakness, and tongue atrophy. His mother, maternal uncle, two sisters, and son suffered from the same symptoms. Electrophysiological studies revealed signs of chronic denervation in the cervical and lumbar regions, mild sympathetic autonomic dysfunction, and bilateral facial nerve dysfunction. Diagnostic whole-exome sequencing (WES) revealed a p.D214Y heterozygous mutation in the gelsolin gene in affected members. We present the first report of a Korean family with HGA diagnosed by WES. WES facilitated a clinical diagnosis of HGA in patients with undiagnosed neuropathies.

Adseverin mediates RANKL-induced osteoclastogenesis by regulating NFATc1

Adseverin is a Ca2+-dependent actin filament-severing protein that has been reported to regulate exocytosis via rearrangements of the actin cytoskeleton in secretory cells. However, the role of adseverin in bone cells has not yet been well characterized. Here, we investigated the role of adseverin in osteoclastogenesis using primary osteoclast precursor cells. Adseverin expression was upregulated during RANKL (receptor activator of nuclear factor-kappaB ligand)-induced osteoclast differentiation. Moreover, genetic silencing of adseverin decreased the number of osteoclasts generated by RANKL. Adseverin knockdown also suppressed the RANKL-mediated induction of nuclear factor of activated T-cell c1 (NFATc1), which is a key transcription factor in osteoclastogenesis. In addition, adseverin knockdown impaired bone resorption and the secretion of bone-degrading enzymes from osteoclasts. These effects were accompanied by decreased NFATc1 expression and the activation of nuclear factor-kappaB. Collectively, our results indicate that adseverin has a crucial role in osteoclastogenesis by regulating NFATc1.

Gelsolin level for prognostic evaluation in patients with critically illness / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To investigate the changes of plasma gelsolin level in patients with critical illness and its application in prognostic evaluation.</p><p><b>METHODS</b>Ninety six critically ill patients admitted in ICU of Sichuan Provincial People's Hospital from February 2012 to December 2013 were enrolled in the prospective cohort study. Plasma gelsolin levels were detected with enzyme linked immunosorbent assay (ELISA) at admission (d1), d2, d4 and d8 after admission, and also detected in blood samples of 186 healthy subjects as controls. Logistic regression model was used to analyze the relationship between the level of plasma gelsolin and prognosis of patients.</p><p><b>RESULTS</b>The average levels of plasma gelsolin were significantly lower in critically ill patients than those in control subjects (F=1986.37, P<0.01). There was significant difference in overall level of gelsolin between survival patients and fatal patients (F=16.691, P<0.01). APACHE Ⅱ score was associated with survival outcomes (r=0.489, P=0.009); the APACHE Ⅱ score was significantly higher in fatal patients than that in survival patients (29.5±7.7 vs 22.1±5.7, t=5.375, P<0.01). There was a negative correlation between plasma gelsolin levels and fatal outcomes (r=-0.512, P<0.01). Logistic regression analysis showed that the overall plasma gelsolin levels and the last measured level was a prognostic factor for critically ill patients (P<0.05).</p><p><b>CONCLUSION</b>Plasma gelsolin levels are correlated with the severity of critically ill patients, and plasma gelsolin can be used as indicator of prognosis.</p>

Plasma gelsolin level and its relationship with the prognosis of patients with severe burns / 中华烧伤杂志

<p><b>OBJECTIVE</b>To observe the changes in plasma gelsolin (pGSN) level of patients with severe burn and to explore its relationship with sepsis and death of patients.</p><p><b>METHODS</b>One hundred and two patients with total burn area equal to or larger than 30% TBSA hospitalized from May 2010 to May 2012 were included as burn group. Twenty-five healthy volunteers were recruited as healthy control group. Peripheral venous blood of patients was harvested on post burn day (PBD) 1, 3, 7, 14, and 21 to determine the pGSN level with double antibody sandwich ELISA kits, and the same maneuver was carried out in healthy volunteers. (1) Patients in burn group were divided into three groups by burn size: small burn area group (30% - 49% TBSA, n = 39), medium burn area group (larger than 49% and smaller than or equal to 69% TBSA, n = 33), and large burn area group (larger than 69% and smaller than or equal to 99% TBSA, n = 30). (2) According to diagnostic criteria of burn sepsis, patients in burn group were divided into sepsis group (n = 43) and non-sepsis group (n = 59). (3) According to the prognosis of patients with sepsis, patients in sepsis group were further divided into non-survival sepsis group (n = 14) and survival sepsis group (n = 29). The levels of pGSN in above groups were compared, and their relationship with sepsis and death of patients was analyzed. Data were analyzed with analysis of variance, LSD test and one-way Logistic regressions.</p><p><b>RESULTS</b>(1) Levels of pGSN in burn group were obviously lower than those of healthy control group on PBD 1, 3, 7, 14, and 21 (with F values respectively 140.01, 369.52, 702.15, 360.14, 84.16, P values all below 0.01). (2) The mean levels of pGSN in large, medium, and small burn area groups at five time points were (43 ± 11), (85 ± 23), (124 ± 38) mg/L, showing statistically significant differences among them (F = 367.76, P < 0.01), and they were all lower than that of healthy control group [(326 ± 51) mg/L, P values all below 0.01]. (3) The mean levels of pGSN in sepsis group and non-sepsis group at the five time points were (77 ± 12), (122 ± 38) mg/L. Levels of pGSN in sepsis group were lower than those in non-sepsis group on PBD 3, 7, 14, and 21 (with F values respectively 30.35, 111.59, 209.36, 422.76, P values all below 0.01). (4) The mean levels of pGSN in non-survival sepsis group and survival sepsis group at the five time points were (53 ± 8) and (103 ± 25) mg/L. Levels of pGSN in non-survival sepsis group were lower than those in survival sepsis group on PBD 1, 3, 7, 14, and 21 (with F values respectively 9.05, 18.48, 41.34, 107.11, 180.48, P values all below 0.01). (5) Logistic regression analysis showed that the level of pGSN is the independent risk factor related to the complication of sepsis (odds ratio: 5.44, 95% confidence interval: 2.35 - 12.74, P < 0.01) and death (odds ratio: 5.52, 95% confidence interval: 2.34 - 12.19, P < 0.01) in burn patients.</p><p><b>CONCLUSIONS</b>Severe burn injury could down-regulate the pGSN level of patients, and it decreases along with the increase in the area and severity of burn trauma. pGSN level appears to be an early prognostic marker for patients suffering from severe burns.</p>

Brain site-specific proteome changes in aging-related dementia

This study is aimed at gaining insights into the brain site-specific proteomic senescence signature while comparing physiologically aged brains with aging-related dementia brains (for example, Alzheimer's disease (AD)). Our study of proteomic differences within the hippocampus (Hp), parietal cortex (pCx) and cerebellum (Cb) could provide conceptual insights into the molecular mechanisms involved in aging-related neurodegeneration. Using an isobaric tag for relative and absolute quantitation (iTRAQ)-based two-dimensional liquid chromatography coupled with tandem mass spectrometry (2D-LC-MS/MS) brain site-specific proteomic strategy, we identified 950 proteins in the Hp, pCx and Cb of AD brains. Of these proteins, 31 were significantly altered. Most of the differentially regulated proteins are involved in molecular transport, nervous system development, synaptic plasticity and apoptosis. Particularly, proteins such as Gelsolin (GSN), Tenascin-R (TNR) and AHNAK could potentially act as novel biomarkers of aging-related neurodegeneration. Importantly, our Ingenuity Pathway Analysis (IPA)-based network analysis further revealed ubiquitin C (UBC) as a pivotal protein to interact with diverse AD-associated pathophysiological molecular factors and suggests the reduced ubiquitin proteasome degradation system (UPS) as one of the causative factors of AD.

Lattice Corneal Dystrophy, Gelsolin Type: The First Case Report in Korea

PURPOSE: To report the first case of lattice corneal dystrophy, gelsolin type in Korea. CASE SUMMARY: A 61-year-old man visited our clinic with severe dry eye symptom in both eyes. Clinical examination revealed in both eyes a visual acuity of 0.7 without correction and intraocular pressure of 18 mm Hg. On slit-lamp examination, both corneas had scattered lattice lines at various depths within the stroma with punctate epithelial erosions. The patient had characteristic features of Meretoja syndrome, including cranial neuropathy characterized by dermatochalasis and facial weakness, and was positive for the gelsolin mutation according to DNA analysis. This is the first description of a patient with lattice corneal dystrophy, gelsolin type in Korea. CONCLUSIONS: This is the first description of a patient with lattice corneal dystrophy, gelsolin type in Korea and demonstrates the importance of recognizing the systemic and ophthalmic features for appropriate management of the condition.

Increased expression of serum gelsolin in patients with osteosarcoma / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Identification of potential serum biomarkers of osteosarcoma to aid in its early diagnosis and in the discovery of possible therapeutic targets is an area of increasing interest.</p><p><b>METHODS</b>Two-dimensional difference-in-gel electrophoresis was used to assess multiple serum samples in patients with osteosarcoma. In addition, differential expression of protein biomarkers was characterized in osteosarcoma serum by using matrix-assisted desorption/ionization time-of-flight mass spectrometry coupled with database interrogation. Serum samples from four individuals with osteosarcoma and four age- and sex-matched healthy control subjects were compared.</p><p><b>RESULTS</b>Fifty-eight significant protein spot features in the osteosarcoma sera were found. These spot features were excised, digested with trypsin, and analyzed with mass spectrometry. Gelsolin was down-regulated only in osteosarcoma. Furthermore, Western blotting and enzyme linked immunosorbent assay (ELISA) confirmed decreased levels of gelsolin in the osteosarcoma serum samples.</p><p><b>CONCLUSIONS</b>These results indicated that gelsolin might have great potential as a biomarker of osteosarcoma and as a potential target for gene therapy.</p>

Prognostic significance of gelsolin and MMP12 in Langerhans cell histiocytosis / 대한혈액학회지

BACKGROUND: Gelsolin and matrix metalloproteinase 12 (MMP12) expression has been reported in Langerhans cell histiocytosis (LCH), but the clinical significance of this expression is unknown. We investigated the associations of these proteins with clinical manifestations in patients diagnosed with LCH. METHODS: We performed a retrospective analysis of clinical data from patients diagnosed with LCH and followed up between 1998 and 2008. Available formalin-fixed, paraffin-embedded specimens were used for gelsolin and MMP12 immunohistochemical staining. We analyzed the expression levels of these proteins and their associations with LCH clinical features. RESULTS: Specimens from 36 patients (20 males, 16 females) with a diagnosis of LCH based on CD1a positivity with clinical manifestations were available for immunohistochemical staining. Median patient age was 62 months (range, 5 to 207). The expression of gelsolin varied; it was high in 17 patients (47.2%), low in 11 patients (30.6%), and absent in 8 patients (22.2%). The high gelsolin expression group had a higher tendency for multi-organ and risk organ involvement, although the trend was not statistically significant. MMP12 was detected only in 7 patients (19.4%) who showed multi-system involvement (P=0.018) and lower event-free survival (P=0.002) in comparison to patients with negative MMP12 staining. CONCLUSION: Gelsolin and MMP12 expression may be associated with the clinical course of LCH, and MMP12 expression may be particularly associated with severe LCH. Further studies of larger populations are needed to define the precise role and significance of gelsolin and MMP12 in the pathogenesis of LCH.

Danish type gelsolin-related amyloidosis in a Brazilian family: case reports / Amiloidose familiar relacionada ao gene gelsolin em uma família brasileira: relato de casos

Familial amyloidosis of the Finnish type (FAF) is an autosomal dominant form of systemic amyloidosis showing marked geographic clustering in Finland. The disease is caused by a point mutation, 654G-A, in the gelsolin gene. The Danish-subtype of FAF has been previously described in three families, the patients present clinical findings similar to FAF, and the mutation 654G-T in the gelsolin gene. Three members from two generations of the same family, with familial amyloidosis, were screened for mutations in the GSN gene. Genomic DNA was extracted from peripheral blood lymphocytes and the polymerase chain reaction (PCR) was carried out under standard conditions, using appropriate primers. Sequence analysis showed the presence of a G to T transition at nucleotide 654 of the gelsolin gene. This is the first report of gelsolin-related familial amyloidosis in a Brazilian family, and the result is particularly significant as this pedigree presents an unusual mutation, described previously in three families, with no known Finnish ancestors (Danish type).

Amiloidose familiar do tipo finlandes (FAF) é uma forma de amiloidose sistêmica autossômica dominante com grande concentração geográfica na Finlândia. É causada por uma mutação, 654G-A, no gene gelsolin. O subtipo dinamarquês da FAF foi previamente descrito em três famílias, com achados clínicos similares mas com a mutação 654G-T no gene gelsolin. Três membros de duas gerações da mesma família, com diagnóstico de amiloidose familiar, foram submetidos a screening de mutações no gene gelsolin. O DNA genômico foi extraído de linfócitos do sangue periférico, sendo realizada reação em cadeia de polimerase (PCR) em condições padronizadas. A análise do sequenciamento revelou uma transição de G para T no nucleotidio 654 do gene gelsolin. Este é o primeiro relato de uma amiloidose familiar relacionada ao gene gelsolin em uma família brasileira, que apresenta uma forma rara de mutação, descrita previamente em três famílias, sem ancestrais finlandeses (tipo dinamarquês).

Research on the correlation between platelet gelsolin and blood-stasis syndrome of coronary heart disease / 中国结合医学杂志

<p><b>OBJECTIVE</b>To study the distribution of gelsolin in human platelet and plasma, and the association with blood-stasis syndrome (BSS) of coronary heart disease (CHD).</p><p><b>METHODS</b>Sixty patients with CHD (30 in BSS group and 30 in non-BSS group) and 30 healthy subjects (control group) were included in this study. The classification of the syndrome was based on clinical symptoms and signs. Gelsolin concentration in platelet rich plasma (PRP), platelet poor plasma (PPP), filamentous actin (F-actin) and group-specific component globulin (Gc-globulin) of PPP were determined by enzyme-linked immunosorbent assay (ELISA). The fluorescence intensity of CD62p and cytoplasmic calcium ([Ca(2+)](i)) in human platelets of patients and healthy persons was measured with flow cytometry.</p><p><b>RESULTS</b>Compared with the control group, gelsolin in PRP of the BSS group increased significantly (P<0.01), while that in PPP of the BSS and non-BSS groups decreased markedly (P<0.05), the CD62p, [Ca(2+)](i) of platelet, F-actin, and Gc-globulin of the BSS and non-BSS groups increased significantly (P<0.01). Compared with the non-BSS group, the gelsolin concentration in PRP of BSS group increased significantly (P<0.01), the [Ca(2+)](i) of platelet of the BSS group increased markedly (P<0.01), while the F-actin and Gc-globulin of the BSS group had no statistical defference (P>0.05).</p><p><b>CONCLUSIONS</b>Gelsolin concentration in PRP was increased and accompanied by the elevated [Ca(2+)](i) of platelet in CHD with BSS, while gelsolin in PPP were lowered markedly. We speculate that plasma gelsolin may clear F-actin from circulation, thus resulting in depletion of plasma gelsolin significantly. This, in addition to the increased calcium influx of platelets, may lead to the gelsolin abnormal expression on platelets during the process of BSS in CHD. Therefore, platelet gelsolin may serve as a new potential biomarker and a therapeutic target of BSS in CHD.</p>

Detection of serum biomakers of osteosarcoma by proteomic profiling / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To detect differentially expressed proteins in serum of patient with osteosarcoma.</p><p><b>METHODS</b>8 serum protein samples were recruited (4 cases of osteosarcoma and 4 cases of normal adults), cross-labeled with variant CyDye, followed by two-dimensional differential in-gel electrophoresis (2-D DIGE), image analysis, and identified by matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF-MS).</p><p><b>RESULTS</b>24 protein spot-features were significantly increased, and 34 were significantly decreased in the serum from patients with osteosarcoma relative to the controls. The mass spectrometry analysis revealed 18 unique proteins that were increased, and 25 unique proteins decreased in the serum of patients with osteosarcoma. Gelsolin was down-regulated in osteosarcoma, and Western blotting also confirmed a decreased level of gelsolin in the serum of patients with osteosarcoma.</p><p><b>CONCLUSION</b>Our results indicate that gelsolin may have great potential as a biomarker of osteosarcoma and as a potential target for therapy. These preliminary data suggest that incorporation of more samples and new datasets will permit the identification of serum biomarkers for osteosarcoma.</p>

Preliminary Report of Short-Term Proteomic Changes following Bilateral Oophorectomy in the Female Rat Bladder Tissue

PURPOSE: The pathophysiological mechanisms of the bladder dysfunction in postmenopausal state are not well understood especially in moleclular level. Therefore we investigated the changes of bladder in female rat following bilateral ovariectomy by proteomic approach. MATERIALS AND METHODS: A total 10 female Sprague-Dawley rats were obtained at 8 weeks of age and randomly divided into 2 groups in each 5 rats; sham operation group as the control group and the bilateral ovariectomy group. Whole urinary bladders of the rats were excised 4 weeks after the beginning of the experiment. Conventional proteomics was performed with high resolution 2-D gel electrophoresis followed by computational image analysis and protein identification using mass spectrometry. RESULTS: Bladder weight was not changed by oophorectomy. A comparison of bladder of ovariectomy group with control showed that 8 proteins; Eukaryotic translation initiation factor 5A was over-expressed, and chaperone grp 75 precursor, guanine deaminase, keratin complex 2, Gelsolin precursor, peroxiredoxin 2, Enol protein and contrapsin-like inhibitor 1 precursor were under-expressed in the oophorectomy group. CONCLUSION: These data suggested that the bilateral oophorectomy might make a bladder to have a cellular apoptosis and a change of contractility in the rat bladder. However more information is needed in human bladder tissue for clinical usage and long-term proteomic changes are needed.

Heat-Shock Protein 70 Attenuates Caspase-3 Activation and DNA Fragmentation Following Focal Cerebral Ischemia

BACKGROUND: Recently, HSP70 has been shown to act as an inhibitor of apoptotic pathways in the cell culture following heat shock; however, little information is available on the mechanism of neuroprotection after cerebral ischemia. In this study, our purpose is to investigate whether the HSP70 protein can protect apoptotic cell death after focal cerebral ischemia. METHODS: hsp70.1 knockout (KO) and wild-type (WT) mice were subjected to transient middle cerebral artery occlusion for 2 hours. At 22 hours, we measured infarction volumes, and detected DNA fragmentation with TUNEL staining. HSP70 and hsp70.1 mRNA expression were analyzed by Western blots and Northern blots, respectively. Caspase-3 activation was examined with Western blots and caspase-3 activity assay. RESULTS: hsp70.1 mRNA was not detected in hsp70.1 KO mice after ischemia, and HSP70 expression was markedly suppressed in KO mice versus WT mice. The infarction volume was significantly larger in the KO (82.1 +/- 9.5 mm3) than in the WT (58.4 +/- 10.3 mm3; p<0.05) 24hours later. Caspase-3 activation was also significantly enhanced in KO mice versus WT mice, as evidenced by higher levels of activated caspase-3 and cleaved gelsolin, as determined by Western blotting and caspase-3 activity assay. TUNEL-positive apoptotic cells were much higher in the KO (1.94 +/- 0.61 X 10(3)/mm2) than in the WT (1.05 +/- 0.35 X 10(3)/mm2; p<0.05) in the cortex, but not in the striatum. CONCLUSIONS: We conclude that that HSP70 acts as a strong inhibitor of apoptosis via blocking caspase-3 activation following focal cerebral ischemia.

Features of host cell invasion by different infective forms of Trypanosoma cruzi

Through its life cycle from the insect vector to mammalian hosts Trypanosoma cruzi has developed clever strategies to reach the intracellular milieu where it grows sheltered from the hosts' immune system. We have been interested in several aspects of in vitro interactions of different infective forms of the parasite with cultured mammalian cells. We have observed that not only the classically infective trypomastigotes but also amastigotes, originated from the extracellular differentiation of trypomastigotes, can infect cultured cells. Interestingly, the process of invasion of different parasite infective forms is remarkably distinct and also highly dependent on the host cell type.