Biomedical subjects

Chumpon Wilasrusmee

Publications and source records attributed to Chumpon Wilasrusmee.

At least 19 recordsLinked to original sources

PubMed2006

Combined hepatocellular and cholangiocarcinoma: clinical features and prognostic study in a Thai population.

BACKGROUND/PURPOSE: Combined hepatocellular and cholangiocarcinoma (HCC-CC) is an uncommon subtype of primary liver cancer, the clinicopathological features of which have rarely been reported in detail. Some authors believe that HCC-CC behaves like HCC, but biliary differentiation may be associated with poorer prognosis. Moreover, CC has more frequent lymph node metastases. In this study, we aimed to determine the clinical course and survival outcome of HCC-CC patients in a Thai population by comparing them with patients with ordinary HCC. METHODS: The clinicopathological features of patients who were diagnosed with HCC-CC at Ramathibodi Hospital during 2000-2004 were retrospectively studied by comparing them with the features of patients suffering from ordinary HCC. Twenty-five patients who were diagnosed with HCC-CC were included in this study, and subsequently 50 patients with HCC who had tissues taken during the same period were selected randomly from among 148 HCC patients. Statistical analysis was done by using SPSS version 10.0. The Kaplan-Meier method was used to assess the survival rate. Multiple logistic regression analysis was performed to assess correlations. A value of P < 0.05 was considered statistically significant. RESULTS: There were no significant differences in etiologic risk factors between HCC-CC and HCC patients: cirrhosis (50% vs 44%), chronic alcohol abuse (36% vs 43%), presence of hepatitis B surface antigen (HBsAg; 66% vs 78%) and presence of hepatitis C virus (HCV) antibody (13% vs 3%). The serum alpha-fetoprotein (AFP) value in the HCC-CC group was lower than that in the HCC group (5.87 vs 41.46 ng/ml). No differences in tumor characteristics or liver status (tumor size, presence of multinodular lesions, portal vein thrombosis, intrahepatic bile duct dilatation, intraabdominal lymphadenopathy, extrahepatic metastasis, liver cirrhosis, portal hypertension, and ascites) between these two groups were found. The overall median survival of HCC-CC patients was 38 weeks while that of HCC patients was 54 weeks. Multivariate analysis showed that elevated carbohydrate antigen (CA)19-9 (>/=80 U/ml) and the presence of intrahepatic bile duct dilatation were independent risk factors for worse survival. CONCLUSIONS: The demographic and clinical features of patients with combined HCC-CC were similar to those of patients with HCC. The presence of cholangiocellular differentiation appeared to worsen the prognosis when compared with pure HCC, although this difference did not reach statistical significance. An increased CA19-9 level and intrahepatic bile duct dilatation in patients with HCC-CC were considered to be independent factors that suggested poor prognosis.

Adult↗

PubMed2006

Comparative study of tailor-made mesh plug herniorrhaphy versus Lichtenstein herniorrhaphy versus Bassini operation: a prospective clinical trial.

OBJECTIVE: Operations to cure inguinal hernia are among the most common surgical procedures. However, the most effective surgical technique for inguinal hernia repair is unknown, and the recurrence at 5 years varies between 1% and 10%. Surgical techniques and implanted materials are crucial to the result of and costs associated with hernia repair. The objective of this study was to determine whether the tailor-made mesh plug for inguinal hernia repair was as effective and safe as other methods of herniorrhaphy. METHODS: Of 94 patients who had a primary diagnosis of inguinal hernia prospectively included in the study, 25 were treated with tailor-made mesh plug herniorrhaphy, 26 with Lichtenstein herniorrhaphy and 36 with the Bassini operation. The primary outcome was the recurrence of hernia at 1 year, and secondary outcomes included surgical complications and hospital stay. RESULTS: There was no postoperative mortality in this study. Three patients had recurrence after Bassini operation, but there was no recurrent hernia after Lichtenstein or mesh plug herniorrhaphy. Groin swelling and ecchymosis were found in two patients (1 tailor-made mesh plug, 1 Lichtenstein herniorrhaphy). No surgical site infection occurred. Mean operating time was 60 minutes (range, 45-75 minutes) for tailor-made mesh plug herniorrhaphy, 82 minutes (range, 30-120 minutes) for Lichtenstein herniorrhaphy, and 82 minutes (range, 30-135 minutes) for the Bassini operation. CONCLUSION: Tailor-made mesh plug herniorrhaphy is a safe operation. The mesh plug material (Mersilene) was cheap. The recurrence rate was lower with tailor-made mesh plug herniorrhaphy than with the Bassini operation, but equal to that with Lichtenstein herniorrhaphy. Postoperative complications did not differ among all operations.

Adolescent↗

PubMed2006

Endoscopic removal of one live biliary Fasciola gigantica.

Biliary fascioliasis was diagnosed in a woman from Angthong province, who presented herself with anorexia, weight loss, and jaundice for one month. Intraoperative retrograded cholangiopancreatography revealed a filling defect considered as a stone and bile sludge. By the sphincterotomy and balloon-extraction technique, one live fluke was removed and identified as Fasciola gigantica. A single dose of praziquantel, 25 mg/kg of body weight/day, was given although the postoperative stool examination revealed no Fasciola spp. egg. The patient was doing well after the fluke removal. According to a previous review, in this country, Ayutthaya is the southernmost province for the distribution of fascioliasis.

Aged↗

PubMed2004

The effect of allo-injury in an in vitro model of allograft microvasculature.

Endothelial cells are critical to the integrity of allograft vasculature and can be damaged by alloreactive T cells or soluble mediators of alloreactivity. The biochemical effects of T cell-mediated damage to the endothelial cells have been studied, but not the structural and morphological effects of allo-injury on endothelial cells in the allograft. We utilized an assay that reproduces microvasculature in vitro to study the effect of alloreactivity on endothelial cells. In this assay, endothelial cells are induced into capillary-like networks that simulate microvascular capillaries. We studied the effect of allogeneic T cells and of soluble mediators from both mixed lymphocyte cultures (MLCs) and rejected heart allograft tissue on the in vitro capillaries. We found that both allogeneic T cells and soluble mediators inhibit the formation of the in vitro endothelial capillaries, suggesting that they cause a mild-to-moderate dysfunction of the endothelial cells. The inhibitory effect of the soluble mediators seems to be mediated, at least partly, by IFN-gamma, since this effect was prevented by antibody to IFN-gamma. Furthermore, pre-incubation of the in vitro capillaries with IFN-gamma appeared to magnify the effect of allogeneic T cells, as shown by a complete breakdown of well-formed in vitro capillary networks. Our experiments suggest that the in vitro capillary-tube model reflects structural injury to allograft vasculature by alloreactive T cells and their soluble mediators.

Animals↗

PubMed2004

Ultrastructural changes in cirrhotic and noncirrhotic patients due to hepatectomy.

BACKGROUND/PURPOSE: Alterations at the ultrastructural level can be identified prior to histological change in the early phase of irreversible cell damage. The aim of this investigation was to compare the ultrastructural changes in cirrhotic and noncirrhotic liver in response to ischemic and reperfusion injury due to hepatectomy. METHODS: Hepatic resections using the same technique were performed in cirrhotic and noncirrhotic patients. Three biopsy specimens (Tru cut) from each patient, in the unresected part of the liver, were studied by transmission electron microscopy: immediately after laparotomy, before releasing of the porta hepatis clamp (ischemic phase), and 30-45 min after reperfusion. RESULTS: All patients did well after surgery, except for 1 cirrhotic patient who died of liver failure. There were no significant differences in operative time, blood loss, and inflow occlusion times in any of the 15 patients. We found that morphological changes were the same in the 10 non-cirrhotic and 4 cirrhotic patients. Changes during the ischemic phase included nuclear membrane deformity, focal chromatin condensation at the nuclear margin, and swelling of both mitochondria and endoplasmic reticulum. In the reperfusion phase, there were early irreversible changes in the nuclei of some hepatocytes and intramitochondrial particles and increased vacuolization in cytoplasm. Endothelial cells, Kupffer cells, bile canaliculi, and Ito cells were not affected in either the ischemic or the reperfusion phase. However, in the 1 cirrhotic patient who died of liver failure, there were marked swelling and dilated cristae in mitochondria during the ischemic phase and deformity of Ito cells during the reperfusion phase. CONCLUSIONS: In this, the first report of ultrastructural changes due to hepatectomy in cirrhotic patients, we found that the changes were the same as those in non-cirrhotic patients, except for the one cirrhotic patient who had postoperative liver failure.

Adult↗

PubMed2004

Signal transduction pathway in endothelial dysfunction.

BACKGROUND: Endothelial dysfunction is an important feature of sepsis, acute respiratory distress syndrome (ARDS), and other infectious conditions. Previously, we reported an in vitro model to study endothelial dysfunction, in which endothelial cells are induced to form capillary tube networks by culturing on a basement membrane matrix (Matrigel). In this study, we defined the signal transduction pathways that lead to endothelial cell function and capillary disruption characteristic of sepsis and other infectious conditions. METHODS: Human aortic endothelial cells (HAEC) were cultured on a laminin-rich matrix to form capillary-like networks. The HAECs were treated with a protein tyrosine phosphatase inhibitor (sodium orthovanadate), a phosphoinositon-3-phosphate inhibitor (wortmannin), or a protein kinase C inhibitor (bisindolylmaleimide) before capillary tubes had formed or after the capillary tubes had matured. The degree of capillary tube formation was quantified by counting the intersection of capillary networks in triplicate wells. Statistical significance was determined by analysis of variance. RESULTS: Endothelial dysfunction occurred after inhibition of protein tyrosine phosphatase or protein kinase C. Whereas inhibition of phosphoinositon-3-phosphate did not cause endothelial dysfunction, sodium orthovanadate (2-20 microM) and bisindolylmaleimide (2-10 microM) significantly reduced capillary networks. The mean +/- SD of the number of capillary tubes in the control, sodium orthovanadate-treated, and bisindolylmaleimide-treated groups were 251.0 +/- 7.0, 65.6 +/- 9.9 (p < 0.001), and 181.7 +/- 0.1 (p < 0.001), respectively. Sodium orthovanadate (20-200 microM) and bisindolylmaleimide (10-100 microM) inhibited capillary tube formation. At higher concentrations, sodium orthovanadate (> 200 microM) and bisindolylmaleimide (>100 microM) disrupted mature capillary tubes. CONCLUSIONS: Our results suggest that PKC and protein tyrosine phosphatase play a role in endothelial dysfunction by interfering with the phosphorylation signals within endothelial cells. These mechanisms may be important in the endothelial dysfunction in sepsis and other infectious conditions.

Analysis of Variance↗

PubMed2004

Augmentation of ischemia/reperfusion injury to endothelial cells by cyclosporin A.

Ischemia/reperfusion (I/R) carries significant injury to endothelial cells in transplanted organs and is an important factor in chronic rejection. Immunosuppressive drugs, notably cyclosporin A (CyA) and FK506, can potentially augment this injury. Here, our goal was to determine the combined effects of I/R and CyA or FK506 on endothelial cells. Transformed mouse endothelial cells (SVEC 4-10) were subjected to ischemia or I/R for 2-24 hours by incubating cells in 100 per cent N2 (ischemia) followed by 5 per cent CO2 and 95 per cent O2 (reperfusion) for 24 hours. In separate experiments, CyA or FK506 was added to cells subjected to ischemia or I/R. Nonviable cells were determined by Trypan blue exclusion assay. All experiments (done in triplicate) were analyzed by Student's t test. Increasing ischemia times resulted in a greater number of nonviable cells (2% nonviable cells at 0 hours and 57% at 24 hours of I/R). Addition of CyA significantly increased the number of nonviable cells when compared with the control (I/R only) group (P = 0.014). Interestingly, FK506 did not increase the percentage of nonviable cells compared with the control group (P = 0.2). Unlike FK506, CyA augments I/R injury to endothelial cells in vitro. These findings could be relevant in chronic rejection and transplantation.

Analysis of Variance↗

PubMed2003

Initial angiogenic response in reduced renal mass after transplantation.

INTRODUCTION: Shortage of organs is a major problem in kidney transplantation and requires novel strategies to increase the number of kidney transplants. To reduce the shortage of kidneys, we have proposed transplantation of two halves of one kidney into two recipients (hemirenal transplantation, HRT) and have shown its feasibility in pig and human kidneys. However, reduced renal mass can lead to progressive renal failure in rodents and can reduce the longevity of kidney transplants in humans. Recent studies suggest that derangement of angiogenesis plays a role in the progressive renal failure after reduction in renal mass in rodents. However, since the renal physiology of rats is different from that of large animals, we studied angiogenesis in reduced renal mass transplants in pigs and determined if the reduction in renal mass has the same effect in large animals as that in rodents. MATERIALS AND METHODS: Kidney autotransplantation was performed in domestic outbred swine. Heminephrectomy of the autotransplanted kidney and nephrectomy of the contralateral kidney were performed 1 week after transplantation to reduce the renal mass. Four weeks after transplantation, the pigs were sacrificed and the hemirenal and control nephrectomy specimens were processed for morphometric analysis of glomerular capillary density and immunohistochemical analysis of VEGF expression. Soluble extracts from the kidneys were tested in an in vitro angiogenesis assay to determine their activity to influence angiogenesis. Statistical analysis with ANOVA was performed on the glomerular capillary density in kidney specimens. RESULTS: All these parameters of angiogenesis were increased in the reduced renal mass autotransplants as compared to normal kidneys or whole kidney autotransplants. Glomerular capillary density was increased significantly after reduction in renal mass. VEGF expression also was increased progressively by the third week after reduction in renal mass. Soluble extract from the reduced renal mass transplants significantly increased the in vitro angiogenesis. CONCLUSION: This is the first study to demonstrate that angiogenesis is increased in the initial stages of reduction in renal mass after transplantation in a large animal model. Increased angiogenesis was found in this model earlier than reported in small animal models (2 weeks in pigs versus 6 weeks in rats). Taken together with other studies, our data suggest that derangement in angiogenesis could play an important role in long-term graft function after hemirenal transplantation.

Animals↗

PubMed2003

Role of endothelin-1 in microvascular dysfunction caused by cyclosporin A.

BACKGROUND: Endothelin-1 (ET-1), a potent vasoconstrictive peptide, is implicated in cyclosporin A (CyA) vasculopathy. Previously we have demonstrated, in an in vitro model of endothelial capillaries, that CyA inhibits the formation of the capillaries and, in high doses, disrupts the capillaries. This study addresses the role of ET-1 in CyA-induced endothelial dysfunction of the in vitro capillaries. STUDY DESIGN: Endothelial cells (ECs) were cultured on a laminin-rich matrix, Matrigel, to form capillary-like networks. The ECs were treated with CyA either before capillary tube formation or after capillary tubes had formed. ppET-1 gene expression was studied by reverse transcriptase polymerase chain reaction. To determine if ET-1 was involved in the CyA-mediated disruption of the in vitro capillaries, ET-1 binding to the endothelial cells was blocked by ET-1 antibody and ET receptor antagonists. The effects of exogenous ET-1 were also studied. The results were quantified by counting the number of capillary networks, and the statistical significance was determined with ANOVA. RESULTS: ppET-1 was expressed in ECs during capillary tube formation, but disappeared once capillary tubes had matured. The ppET-1 gene expression reappeared when the capillary tubes were exposed to CyA. Exogenous ET-1 partially reversed the inhibition of tube formation by cyclohexamide, allowing initiation of tube formation. CyA-mediated capillary dysfunction was completely prevented by an anti-ET-1 antibody and an ET-B receptor antagonist. CONCLUSIONS: Endothelin-1 plays a significant role in CyA-induced endothelial dysfunction and may play a role in allograft vasculopathy. Blocking of ET-1 is a strategy to prevent endothelial dysfunction caused by CyA.

Analysis of Variance↗

PubMed2003

Morphological and biochemical effects of immunosuppressive drugs in a capillary tube assay for endothelial dysfunction.

Immunosuppressive drugs common in clinical transplantation are known to have untoward effects on the vascular system. The effects of some drugs, notably cyclosporin A (CyA), have been studied on the vascular system, while those of others have not. In the vascular system, endothelial cells are the predominant cell type exposed to intravascular concentrations of immunosuppressive drugs. We therefore studied the effects of drugs common in clinical transplantation on endothelial cells in a capillary tube assay. The endothelial cells in the capillary tubes are morphologically more similar to those in the microvasculature than endothelial cells in monolayers. We studied the kinetics and extent of capillary tube formation and prostacyclin (PGI2) and endothelin-1 (ET-1) release from the in vitro capillaries to determine the morphological and biochemical effects of five immunosuppressive agents on endothelial function. We found a significant difference in the morphological and biochemical effects of the two common calcineurin inhibitors, CyA and tacrolimus (FK506) on capillary morphology in vitro. The former had a pronounced injurious effect on the morphology of the in vitro capillaries, while the latter did not. CyA also significantly increased ET-1 release by the capillaries, but FK506 did not. Mycophenolate mofetil (MMF) was the only other agent that had a moderately injurious effect on the morphology of the in vitro capillaries. Sirolimus (rapamycin) and dexamethasone, similar to FK506, had no effect on the capillary morphology. All these agents, except dexamethasone, increased PGI2 release. Our data suggest that CyA adversely affects the morphology of the microvasculature and that this is mediated, at least partly, by an increased ET-1 release by endothelial cells exposed to CyA. These findings describe a novel effect of CyA and MMF on endothelial cells that could be relevant to understanding the mechanisms of immunosuppressive drug-mediated endothelial injury in clinical transplantation.

Cell Survival↗

PubMed2003

beta1-integrin-ligand disengagement induces in vitro capillary tube disruption mediated by p38 MAPK activity.

BACKGROUND: Disrupting cell-matrix interactions may lead to capillary injury as seen in sepsis and transplant rejection. Previously, we demonstrated capillary disruption mediated by beta1-integrin-ligand disengagement. We now determine whether p38 mitogen-activated protein kinase (MAPK) and extracellular signal-regulated kinase (ERK) pathways are involved in this capillary injury. METHODS: Endothelial capillaries on Matrigel were preincubated with a p38 MAPK inhibitor (SB203580), ERK pathway inhibitor (PD98059), or dimethyl sulfoxide. Subsequently, a beta1-integrin blocking (P5D2) or an irrelevant antibody was added. After 24 hours, capillary integrity was quantified as capillary intersections/well. Antibody-treated cell lysates then were immunoprecipitated with either a phospho-p38 MAPK or phospho-ERK1/2 antibody. Kinase activity was measured with ATF-2 and Elk-1 fusion proteins as substrates for p38 MAPK and ERK, respectively, followed by Western blotting. RESULTS: P5D2 disrupted capillary tubes. Increased p38 MAPK activity at 8 hours and ERK activity at 2 and 8 hours were seen in P5D2-treated lysates. Preincubation with SB203580, but not with PD98059 or DSMO, significantly reduced capillary tube disruption. CONCLUSIONS: The beta1-integrin-ligand disengagement resulted in capillary disruption and stimulated p38 MAPK and ERK activity. In spite of activation of both pathways, the p38 MAPK but not the ERK pathway inhibitor prevented beta1-integrin antibody effects. Inhibiting p38 MAPK may mitigate capillary injury associated with sepsis and transplant rejection.

Antibodies↗

PubMed2003

Amelioration of cyclosporin A effect on microvasculature by endothelin inhibitor.

BACKGROUND: We have previously shown that endothelial injury by cyclosporin A (CyA) is associated with an increased endothelin-1 (ET-1) release. We now sought to determine, in an animal model of angiogenesis, if inhibiting the effect of ET-1 on endothelial cells (ECs) would reverse the CyA-mediated endothelial injury in an animal model of angiogenesis. METHODS: An angiogenic mixture of Matrigel (0.5 ml), fibroblast growth factor (1 ng/ml), vascular endothelial growth factor (100 ng/ml), and heparin (64 unit/ml) was injected as a subcutaneous plug in the flank of C3H mice (n = 5). In experimental groups CyA (20 mg/ml), CyA, and BQ 123 (ET-A receptor antagonist), CyA and PD 142893 (ET-A and ET-B receptor antagonist), or CyA and ET-1 antibody were added to the angiogenic mixture. Angiogenesis in the mixture was quantified by modified planimetric point counting method in skin/Matrigel cross-sections stained with factor VIII to highlight endothelial neocapillaries. Mean +/- SD of angiogenic area was analyzed with analysis of variance and Bonferroni test. The survival curves obtained by Kaplan-Meier analysis were compared between the groups, and the statistical significance of survival and mortality rates was computed by log rank's and Fisher's exact test, respectively. RESULTS: The mean +/- SD of angiogenic area in control animals (without CyA in the angiogenic mixture) was 56.76 +/- 4.2. CyA inhibited angiogenesis in the subcutaneous angiogenic plug. Adding CyA to the angiogenic mixture significantly reduced angiogenic area (5.33 +/- 1.4, P <.001) while vehicle for CyA had no such effect (56.33 +/- 3.8, P =.10). Polyclonal ET-1 antibody or PD 142893 ameliorated the effect of CyA, whereas BQ 123 did not. The mean angiogenic areas in animals with ET-1 antibody, PD 142893, or BQ 123 in the angiogenic mixture were 57.20 +/- 7.5 (P =.06), 46.00 +/- 11.5 (P = 1.0), 8.60 +/- 2.9 (P <.001), respectively. CONCLUSIONS: Our data show that blocking ET-B receptors specifically ameliorates the microvascular injury to the neocapillaries in angiogenesis caused by CyA. Antiendothelin-1 antibody and ETR antagonist (PD 142893) could, therefore, reduce the ill effects of CyA on microvascular endothelium.

Animals↗

PubMed2003

Early hemodynamic changes after renal transplantation: determinants of low central venous pressure in the recipients and correlation with acute renal dysfunction.

BACKGROUND: Transplantation of organs leads to several physiologic changes in the recipients who, during their anephric state on chronic hemodialysis, have increased total body water and several electrolyte imbalances. Several abnormal parameters are observed in the physiology of the renal recipient. The central venous pressure (CVP) in the recipient invariably declines despite vigorous fluid resuscitation for reasons that are not clear at the present time. MATERIAL/METHODS: We studied 77 kidney transplants retrospectively, in which we observed a significant decline in central venous pressure (CVP) in the immediate posttransplant period. This phenomenon occurred despite aggressive fluid management and positive fluid balances averaging nearly four liters. Our analysis included the time course of the phenomenon itself as well as a detailed comparison of various parameters in the recipient and the renal graft for possible correlation with this consistent decline in CVP. RESULTS: Neither the absolute CVP nor the drop in CVP appeared to influence the rate of ATN. Interestingly, we found that the kinetics of the decline in CVP were remarkably similar in recipients of both cadaveric and living-related kidneys. CONCLUSIONS: This finding suggests that the reperfusion injury or a related effect may be responsible for the clinical phenomenon presented in this study.

Adult↗

PubMed2002

A new in vitro model to study endothelial injury.

BACKGROUND: Endothelial dysfunction or "endothelialitis" is a prominent feature in several disease states ranging from atherosclerosis to transplant rejection. This dysfunction is also caused by drugs such as cyclosporin A (CyA) and leads to allograft vasculopathy and eventual graft loss. Despite the frequency and importance of this injury, there is no model to study the morphological effects of endothelial injury and dysfunction in vitro. METHODS: We utilized a model in which mouse endothelial cells (SVEC 4-10) can be induced to form capillary tubes by culturing on a laminin-rich matrix (Matrigel). In this morphological model of endothelial cell function, we studied the effect of varying doses of CyA on two parameters of tube formation: initiation of tube formation and disruption of mature capillary tubes. As a positive control we used IFN-gamma, which inhibited capillary tube formation. We developed this assay in 96-well culture plates to test several samples simultaneously. RESULTS: The assay could be adapted to a 96-well format by optimizing the cell density. Endothelial dysfunction was seen when the endothelial cells were incubated with cyclosporin A, which affected both morphological parameters of tube formation. At higher doses (2-20 microg/ml) CyA both inhibited capillary tube formation and disrupted mature capillary tubes. At lower doses CyA only inhibited the initiation of tube formation; it did not disrupt mature capillary tubes. IL-2 (400-1000 pg/ml) and IFN-gamma (10-400 pg/ml) inhibited initiation of tube formation but did not disrupt mature capillary tubes. None of these agents, including high doses of CyA, impaired endothelial cell viability. CONCLUSION: CyA-induced endothelial dysfunction can be modeled in vitro by this novel morphological assay of capillary tube formation. This assay can discern mild and severe degrees of endothelial dysfunction. The different effects of low and high levels of CyA on capillary tube formation imply that similar dysfunction in vivo may be responsible for allograft vasculopathy caused by CyA. This novel model can also be utilized to study other forms of vasculitis.

Animals↗

PubMed2002

Expression of fetal isoforms of actin after transplantation injury.

Trauma and injury to transplanted organs in the early post-transplant period are significant factors that affect long-term graft survival. Fetal isoforms of actin are integral members of the immediate early gene family and are expressed in response to free radical injury. We therefore studied actin gene expression in heart transplantation to determine if reperfusion injury activates fetal isoforms of actins. Heterotopic cardiac transplantations were performed in mice. mRNA was extracted from allo- and isografted hearts as well as from normal hearts and spleen. Northern hybridization with actin cDNA to alpha and beta/gamma actin mRNA was performed and analyzed by densitometry. The beta/gamma actin gene expression in the transplanted hearts was found to be significantly elevated within 48 h after transplantation. Analysis of beta/gamma actin gene expression in isografts substantiates the possibility of de novo increase in actin expression. Our studies demonstrate for the first time that fetal isoforms of actin are induced in the allograft heart after transplantation.

Actins↗

PubMed2002

Locally derived cytokines and upregulation of MHC class II genes in allografts.

BACKGROUND: In vitro, various cytokines can modulate the level of expression of major histocompatibility complex (MHC) Class II antigens. Major histocompatibility complex Class II hyperexpression occurs in many immunologic disorders in vivo, but the cytokines that affect this are difficult to analyze because they are produced in small amounts, they act locally, and their mRNAs have short half-lives. METHODS: We studied the expression of cytokines known to up-regulate MHC Class II genes in heart allografts in mice from B10.BR donors to B10.D2 recipients by reverse transcription of mRNA and polymerase chain reaction amplification. The I-Abeta(k) gene expression was also studied in the same fully MHC incompatible strain combination. RESULTS: Messenger RNA for interferon (INF)-gamma, interleukin (IL)-4, and tumor necrosis factor (TNF)-alpha, known inducers of MHC Class II expression in vitro, could be detected in allografts either 24 hours before or simultaneously with massive induction of graft specific I-Abeta mRNA. Interleukin-6 mRNA could be detected as early as 1 day after grafting. CONCLUSION: These data suggest that known cytokine up-regulators of MHC Class II genes, i.e., IFN-gamma, IL-4, and TNF-alpha may contribute to the upregulation of graft-specific MHC Class II antigens during an allograft reaction. Also, IL-6 expression in allografts may result from the stress of the grafting procedure, as it is evident very early after grafting.

Animals↗

PubMed2002

In vitro immunomodulatory effects of ten commonly used herbs on murine lymphocytes.

OBJECTIVES: Physicians are increasingly encountering patients who use herbal products. Some of these products are known to modulate the immune system but their scientific basic is not well established. Because these products can affect the host immune system, they could be beneficial in the treatment of immune-related diseases, or alternatively, they could cause inadvertent side-effects. The purpose of this study was to determine which of these common herbal products modulate lymphocyte proliferation in vitro. METHODS: Lymphocyte proliferation assays using concanavalin A (mitogen stimulation) and mixed lymphocyte culture (alloantigen stimulation) were used as in vitro tests to investigate the immunomodulatory effects of 10 commonly used herbal products. RESULTS: Ginger and tea were consistently immunosuppressive while dong quai, milk thistle, and St. John's wort were consistently immunostimulatory in vitro. Ginseng enhanced lymphocyte proliferation only in the mitogen-stimulation assay. The magnitude of the enhancement or suppression of the individual herbal products was different in the two assays. CONCLUSION: Our study provides a uniform survey of the immunomodulatory properties of 10 commonly used herbal products and paves the way for testing these effects in vivo and in clinical setting.

Adjuvants, Immunologic↗

PubMed2002

Neurotrophic and neuroprotective effects of milk thistle (Silybum marianum) on neurons in culture.

Herbal products are being increasingly used as dietary supplements and therapeutic agents. However, much more research must be performed in order to determine the biological basis for their putative clinical effects. We tested the effects of milk thistle (Silybum marianum) extract on the differentiation and survival of cultured neural cells. Milk thistle enhanced nerve growth factor (NGF)-induced neurite outgrowth in PC-12 neural cells and prolonged their survival in culture. Milk thistle extract also protected cultured rat hippocampal neurons against oxidative stress-induced cell death. Our data demonstrate that milk thistle extract can promote neuronal differentiation and survival, suggesting potential benefits of chemicals in this plant on the nervous system.

Animals↗