Huang-Ping Yu

The role of estrogen and receptor agonists in maintaining organ function after trauma-hemorrhage.

ABSTRACT Sex is increasingly recognized as a major factor in the outcome of patients who have trauma and sepsis. Moreover, sex steroids influence chemokine/adhesion molecule expression and neutrophil accumulation. Heat shock proteins, heat shock factor 1, and peroxisome proliferator-activated receptor &ggr; coactivator 1 are regulated by the estrogen receptors and consequently contribute to organ protection after trauma-hemorrhage. Additionally, sex steroids regulate inflammatory cytokines, leading to increased morbidity and mortality. This article deals with trauma-hemorrhage and examines the following: 1) the evidence for sex differences; 2) the mechanisms by which sex hormones affect organ protection; 3) the tissue-specific effect of sex hormone receptors; and 4) the effect of genomic and nongenomic (i.e. membrane-initiated steroid signaling) pathways of sex hormones after trauma. The available information indicates that sex steroids modulate cardiovascular responses after trauma. Thus, alteration or modulation of the prevailing hormone milieu at the time of injury seems to be a novel therapeutic option for improving outcome after injury.

Inhibition of cardiac PGC-1α expression abolishes ERβ agonist-mediated cardioprotection following trauma-hemorrhage

PGC‐1α (peroxisome proliferator‐acti‐vated receptor [PPARγ] coactivator‐1α) activates PPARα and mitochondrial transcription factor A (Tfam), which regulate proteins, fatty acid and ATP metabolism (i.e., FAT/CD36, MCAD, and COX I). Recently we found that the salutary effects of estradiol (E2) on cardiac function following trauma‐hemorrhage (T‐H) are mediated via estrogen receptor (ER)β. In this study we tested the hypothesis that ERβ‐mediated cardioprotection is induced via up‐regulation of PGC‐1α through PPARα or Tfam‐dependent pathway. Male rats underwent T‐H and received ERα agonist propylpyra‐zole‐triol (PPT), ERβ agonist diarylpropionitrile (DPN), E2, or vehicle. Another group was treated with antisense PGC‐1α oligonucleotides prior to administration of DPN. E2 and DPN treatments attenuated the decrease in cardiac mitochondrial ATP, abrogated the T‐H‐induced lipid accumulation, and normalized PGC‐1α, PPARα, FAT/CD36, MCAD, Tfam, and COX I after T‐H. In contrast, PPT administration did not abrogate lipid accumulation. Moreover, in PPT‐treated animals mitochondrial ATP remained significantly lower than those observed in DPN‐ or E2‐treated animals. Prior administration of antisense PGC‐1α prevented DPN‐mediated cardioprotection and increase in ATP levels and Tfam but not in PPARα following T‐H. These findings suggest that the salutary effects of E2 on cardiac function following T‐H are mediated via ERβ up‐regulation of PGC‐1 α through Tfam‐dependent pathway.—Hsieh, Y.‐C., Choudhry, M. A., Yu, H.‐P., Shimizu, T., Yang, S., Suzuki, T., Chen, J., Bland, K. I., Chaudry, I. H. Inhibition of cardiac PGC‐1 α expression abolishes ERβ agonist‐mediated cardioprotection following trauma‐hemorrhage. FASEB J. 20, 1109–1117 (2006)

Flutamide attenuates pro-inflammatory cytokine production and hepatic injury following trauma-hemorrhage via estrogen receptor-related pathway.

Objective:To determine the mechanism by which flutamide administration following trauma-hemorrhage (T-H) decreases cytokine production and hepatic injury under those conditions. Summary Background Data:Although studies have demonstrated that flutamide administration following T-H improves hepatic and immune functions, the mechanism by which flutamide produces the salutary effects remains unknown. Methods:Male Sprague-Dawley rats underwent a 5-cm laparotomy and hemorrhagic shock (40 mm Hg for ∼90 minutes), followed by resuscitation with 4 times the shed blood volume in the form of Ringers lactate. Flutamide (25 mg/kg body weight, sc) was administered at the middle of resuscitation and animals were killed 2 hours thereafter. To block estrogen receptor (ER), ER antagonist ICI 182,780 was administrated with flutamide. Results:Hepatic injury, myeloperoxidase activity, nuclear factor-kappaB (NF-κB) DNA binding activity and protein expression of intercellular adhesion molecule-1, and cytokine-induced neutrophil chemoattractant (CINC-1 and CINC-3) markedly increased following T-H. Hepatic mRNA and plasma IL-6 levels were also elevated following T-H. The alterations in these parameters induced by T-H were significantly attenuated by flutamide administration. The decreased plasma estradiol levels following T-H were restored to sham levels in the flutamide-treated T-H animals. Coadministration of ICI 182,780 prevented those salutary effects of flutamide administration on pro-inflammatory responses and hepatic injury following T-H. Conclusion:These findings suggest that the reduction in the production of pro-inflammatory mediators and hepatic injury produced by flutamide administration following T-H is likely due to the down-regulation in hepatic NF-kappaB DNA binding activity. Moreover, the salutary effects of flutamide administration appear to be mediated at least in part via ER-related pathway.

Estrogen-mediated activation of non-genomic pathway improves macrophages cytokine production following trauma-hemorrhage.

Although 17β‐estradiol (E2) attenuates the alterations in Kupffer cells and splenic macrophages (MΦ) cytokine production following trauma‐hemorrhage, the mechanism by which this occurs remains unknown. Utilizing a cell‐impermeable E2 conjugated with BSA (E2‐BSA), we examined the non‐genomic effects of E2 on the above two cell population cytokine production, MAPK and transcription factors activation following trauma‐hemorrhage. Male Sprague–Dawley rats underwent trauma‐hemorrhage (mean BP 40 mmHg for 90 min, then resuscitation). E2, E2‐BSA (1 mg/kg E2) with or without an estrogen receptor antagonist (ICI 182,780), or vehicle was administrated during resuscitation. Two hrs thereafter, Kupffer cells and SMΦ production of IL‐6, TNF‐α, and IL‐10, activation of MAPK (p38, ERK‐1/2, and JNK), and transcription factors (NF‐κB and AP‐1) were determined. IL‐6, TNF‐α, and IL‐10 productive capacity, MAPK, and transcription factors activation increased in Kupffer cells while they decreased in SMΦ following trauma‐hemorrhage. However, E2 administration normalized all of these alterations. Although E2‐BSA also attenuated the alterations in cytokine production/transcription factors, the values were higher in Kupffer cells and lower in SMΦ compared to shams. In contrast, E2‐BSA prevented trauma‐hemorrhage‐mediated changes in MAPK activation to the same extent as E2. Co‐administration of ICI 182,780 abolished E2‐BSA effects. Although some MAPK inhibitors suppressed cytokine production, the inhibitor effectiveness was dependent on cytokine, cell type and animal condition (trauma‐hemorrhage or sham). Thus, E2 effects on Kupffer cells and SMΦ cytokine production and transcription factors activation following trauma‐hemorrhage are mediated at least in part via non‐genomic pathway and these non‐genomic effects are likely mediated via MAPK pathways. J. Cell. Physiol. 214: 662–672, 2008.

Mitogen activated protein kinase (MAPK) mediates non-genomic pathway of estrogen on T cell cytokine production following trauma-hemorrhage

Although studies have shown 17beta-estradiol (E2) administration following trauma-hemorrhage (T-H) attenuates alterations in T cell cytokine production, it remains unknown whether such effects of E2 are mediated via genomic or non-genomic pathways. In this study, we determined the non-genomic effects of E2 on splenic T cell cytokine production and the role of MAPK following T-H. Male Sprague-Dawley rats underwent T-H (mean BP 40 mmHg for 90 min, then resuscitation). E2, E2 conjugated with BSA (E2-BSA, 1 mg/kg E2) with or without an estrogen receptor antagonist (ICI 182 780), or vehicle was administered during resuscitation. Two hours thereafter, T cell production of IL-2 and IFN-gamma and activation of MAPK (p38, ERK-1/2 and JNK) were determined. The effect of selective MAPK inhibitors on cytokine production was also examined in vitro. IL-2 and IFN-gamma production capacity and MAPK activation decreased in T cells following T-H. However, E2 administration normalized these parameters. Although E2-BSA administration also attenuated suppression in cytokine production, the values were lower compared to sham. In contrast, E2-BSA prevented T-H-induced suppression in MAPK activation to the same extent as E2. Co-administration of ICI 182 780 abolished E2-BSA effects. These findings suggest E2 effects on T cell cytokine production following T-H are mediated at least in part via non-genomic pathway and these non-genomic effects are likely mediated via MAPK pathways.

The role of estrogen receptor subtypes on hepatic neutrophil accumulation following trauma-hemorrhage: direct modulation of CINC-1 production by Kupffer cells.

Although 17beta-estradiol (E2) administration following trauma-hemorrhage (T-H) reduces liver injury by decreasing neutrophil accumulation via estrogen receptor (ER)-alpha, it remains unclear whether cytokine-induced neutrophil chemoattractant (CINC)-1 production by Kupffer cells (KC) is directly modulated by ER-alpha under such condition. Male rats underwent laparotomy and hemorrhagic shock (40 mmHg for 90 min), followed by resuscitation with four times the shed blood volume in the form of Ringers lactate. ER-alpha agonist propyl pyrazole triol (PPT; 5 microg/kg), ER-beta agonist diarylpropionitrile (DPN; 5 microg/kg), E2 (50 microg/kg), or vehicle (10% DMSO) was administered subcutaneously during resuscitation; rats were sacrificed 24h thereafter. KC were isolated and cultured with ER agonists to examine if they directly affect CINC-1 production. T-H increased plasma alanine aminotransferase (ALT; hepatic injury) and hepatic myeloperoxidase (MPO) activity. E2, PPT and DPN administration reduced increased ALT; however, PPT was more effective than DPN. PPT and E2, but not DPN significantly attenuated increased hepatic MPO activity and CINC-1 levels. PPT addition in vitro (10(-7) and 10(-6)M) significantly reduced KC CINC-1 production. In summary, the salutary effects of E2 against hepatic injury are mediated predominantly via ER-alpha which directly modulates KC CINC-1 production and hepatic neutrophil accumulation following T-H.

Hepatic gene expression patterns following trauma-hemorrhage: effect of posttreatment with estrogen.

ABSTRACT The aim of this study was to examine the role of estrogen on hepatic gene expression profiles at an early time point following trauma-hemorrhage in rats. Groups of injured and sham controls receiving estrogen or vehicle were killed 2 h after injury and resuscitation, and liver tissue was harvested. Complementary RNA was synthesized from each RNA sample and hybridized to microarrays. A large number of genes were differentially expressed at the 2-h time point in injured animals with or without estrogen treatment. The upregulation or downregulation of a cohort of 14 of these genes was validated by reverse transcription–polymerase chain reaction. This large-scale microarray analysis shows that at the 2-h time point, there is marked alteration in hepatic gene expression following trauma-hemorrhage. However, estrogen treatment attenuated these changes in injured animals. Pathway analysis demonstrated predominant changes in the expression of genes involved in metabolism, immunity, and apoptosis. Upregulation of low-density lipoprotein receptor, protein phosphatase 1, regulatory subunit 3C, ring-finger protein 11, pyroglutamyl-peptidase I, bactericidal/permeability-increasing protein, integrin, &agr;D, BCL2-like 11, leukemia inhibitory factor receptor, ATPase, Cu++ transporting, &agr; polypeptide, and Mk1 protein was found in estrogen-treated trauma-hemorrhaged animals. Thus, estrogen produces hepatoprotection following trauma-hemorrhage likely via antiapoptosis and improving/restoring metabolism and immunity pathways.

Hepatoprotective Effects of Corilagin Following Hemorrhagic Shock are Through Akt-Dependent Pathway.

ABSTRACT Corilagin, a component of Phyllanthus urinaria extract, possesses antioxidant, thrombolytic, antiatherogenic, and hepatoprotective properties, but the mechanism underlying these effects remains unclear. Previous studies showed that the Akt (protein kinase B) signaling pathway exerts anti-inflammatory and organ protective effects. The aim of this study was to investigate the mechanism of action of corilagin and determine whether these effects are mediated through the Akt-dependent pathway in a trauma-hemorrhagic shock-induced liver injury rodent model. Hemorrhagic shock was induced in male Sprague–Dawley rats; mean blood pressure was maintained at 35 mm Hg to 40 mm Hg for 90 min, followed by fluid resuscitation. During resuscitation, three doses of corilagin alone (1 mg/kg, 5 mg/kg, or 10 mg/kg, intravenously) were administered. Furthermore, a single dose of corilagin (5 mg/kg) with and without Wortmannin (1 mg/kg, PI3K inhibitor), Wortmannin alone, or vehicle was administered. Twenty-four hours after resuscitation, plasma alanine aminotransferase and aspartate aminotransferase concentration and hepatic parameters were measured. One-way ANOVA was used for statistical analysis. Hepatic myeloperoxidase activity and the concentrations of plasma alanine aminotransferase and aspartate aminotransferase, interleukin-6, tumor necrosis factor-&agr;, intercellular adhesion molecule-1, and cytokine-induced neutrophil chemoattractant-1 (CINC-1) and CINC-3 increased following hemorrhagic shock. These parameters were significantly attenuated in corilagin-treated rats following hemorrhagic shock. Hepatic phospho-Akt expression was also higher in corilagin-treated rats than in vehicle-treated rats. The elevation of phospho-Akt was abolished by combined treatment with Wortmannin and corilagin. Our results suggest that corilagin exerts its protective effects on hemorrhagic shock-induced liver injury, at least, via the Akt-dependent pathway.

Hepatoprotective effect of casodex after trauma hemorrhage in a rodent model.

ABSTRACT Casodex (bicalutamide), an androgen receptor antagonist, is used for the treatment of prostate cancer. Recent evidences show that Akt signaling pathway exerts organ-protective effects after injury. The aim of this study was to investigate whether Akt plays any role in the casodex-mediated attenuation of hepatic injury after trauma-hemorrhagic shock. Male Sprague-Dawley rats underwent trauma hemorrhage (mean blood pressure kept at approximately 35–40 mm Hg for 90 min), followed by fluid resuscitation. During resuscitation, a single dose of casodex (5 mg/kg, intravenous) with and without a phosphatidylinositol 3-kinase inhibitor wortmannin (1 mg/kg, intravenous), wortmannin or vehicle was administered. Plasma aspartate aminotransferase and alanine aminotransferase levels and various hepatic parameters were measured at 24 h after resuscitation. One-way analysis of variance and the Tukey test were used for statistical analysis. These results showed that trauma hemorrhage increased hepatic myeloperoxidase activity, interleukin 6 and intercellular adhesion molecule 1 levels, and plasma aspartate aminotransferase and alanine aminotransferase concentrations. In the trauma hemorrhage rats treated with casodex, these parameters were significantly improved. Casodex treatment also increased hepatic phospho-Akt expression compared with vehicle-treated trauma hemorrhaged rats. Coadministration of wortmannin with casodex abolished the casodex-induced advantageous effects on the aforementioned parameters and hepatic injury. Our results suggest that the protective effect of casodex administration on attenuation of hepatic injury after trauma hemorrhage, which is, at least in part, through Akt-dependent pathway.

203: Estrogen-mediated activation of non-genomic pathway improves macrophages cytokine production following trauma-hemorrhage

Although 17beta-estradiol (E2) attenuates the alterations in Kupffer cells and splenic macrophages (MPhi) cytokine production following trauma-hemorrhage, the mechanism by which this occurs remains unknown. Utilizing a cell-impermeable E2 conjugated with BSA (E2-BSA), we examined the non-genomic effects of E2 on the above two cell population cytokine production, MAPK and transcription factors activation following trauma-hemorrhage. Male Sprague-Dawley rats underwent trauma-hemorrhage (mean BP 40 mmHg for 90 min, then resuscitation). E2, E2-BSA (1 mg/kg E2) with or without an estrogen receptor antagonist (ICI 182,780), or vehicle was administrated during resuscitation. Two hrs thereafter, Kupffer cells and SMPhi production of IL-6, TNF-alpha, and IL-10, activation of MAPK (p38, ERK-1/2, and JNK), and transcription factors (NF-kappaB and AP-1) were determined. IL-6, TNF-alpha, and IL-10 productive capacity, MAPK, and transcription factors activation increased in Kupffer cells while they decreased in SMPhi following trauma-hemorrhage. However, E2 administration normalized all of these alterations. Although E2-BSA also attenuated the alterations in cytokine production/transcription factors, the values were higher in Kupffer cells and lower in SMPhi compared to shams. In contrast, E2-BSA prevented trauma-hemorrhage-mediated changes in MAPK activation to the same extent as E2. Co-administration of ICI 182,780 abolished E2-BSA effects. Although some MAPK inhibitors suppressed cytokine production, the inhibitor effectiveness was dependent on cytokine, cell type and animal condition (trauma-hemorrhage or sham). Thus, E2 effects on Kupffer cells and SMPhi cytokine production and transcription factors activation following trauma-hemorrhage are mediated at least in part via non-genomic pathway and these non-genomic effects are likely mediated via MAPK pathways.