| 1. |
- Shao, Linus Ruijin, 1964, et al.
(author)
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Nuclear progesterone receptor A and B isoforms in mouse fallopian tube and uterus: implications for expression, regulation, and cellular function
- 2006
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In: American journal of physiology. - : American Physiological Society. - 0193-1849. ; 291:1
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Journal article (peer-reviewed)abstract
- Progesterone and its interaction with nuclear progesterone receptors (PR) PR-A and PR-B play a critical role in the regulation of female reproductive function in all mammals. However, our knowledge of the regulation and possible cellular function of PR protein isoforms in the fallopian tube and uterus in vivo is still very limited. In the present study, we revealed that equine chorionic gonadotropin (eCG) treatment resulted in a time-dependent increase in expression of both isoforms, reaching a maximal level at 48 h in the fallopian tube. Regulation of PR-A protein expression paralleled that of PR-B protein expression. However, in the uterus PR-B protein levels increased and peaked earlier than PR-A protein levels after eCG treatment. With prolonged exposure to eCG, PR-B protein levels decreased, whereas PR-A protein levels continued to increase. Furthermore, subsequent treatment with human (h)CG decreased the levels of PR protein isoforms in both tissues in parallel with increased endogenous serum progesterone levels. To further elucidate whether progesterone regulates PR protein isoforms, we demonstrated that a time-dependent treatment with progesterone (P(4)) decreased the expression of PR protein isoforms in both tissues, whereas decreases in p27, cyclin D(2), and proliferating cell nuclear antigen protein levels were observed only in the uterus. To define the potential PR-mediated effects on apoptosis, we demonstrated that the PR antagonist treatment increased the levels of PR protein isoforms, induced mitochondrial-associated apoptosis, and decreased in epidermal growth factor (EGF) and EGF receptor protein expression in both tissues. Interestingly, immunohistochemistry indicated that the induction of apoptosis by PR antagonists was predominant in the epithelium, whereas increase in PR protein expression was observed in stromal cells of both tissues. Taken together, these observations suggest that 1) the tissue-specific and hormonal regulation of PR isoform expression in mouse fallopian tube and uterus, where they are potentially involved in regulation of mitochondrial-mediated apoptosis depending on the cellular compartment; and 2) a possible interaction between functional PR protein and growth factor signaling may have a coordinated role for regulating apoptotic process in both tissues in vivo.
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| 2. |
- Shao, Linus Ruijin, 1964, et al.
(author)
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Ciliated epithelial-specific and regional-specific expression and regulation of the estrogen receptor-beta2 in the fallopian tubes of immature rats: a possible mechanism for estrogen-mediated transport process in vivo
- 2007
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In: American journal of physiology. - : American Physiological Society. - 0193-1849 .- 1522-1555. ; 293:1
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Journal article (peer-reviewed)abstract
- Several ERbeta isoforms have been identified in human and rodent tissues, but it is unclear whether each isoform has distinctly different cellular targeting characteristics and physiological functions. We have investigated the intracellular localization and regulatory patterns for ERbeta isoforms in rat fallopian tubes. Western blot analysis reveals that two ERbeta isoforms corresponding to ERbeta1 and ERbeta2 are expressed in rat fallopian tubes. However, ERbeta2 is the predominant form of ERbeta in this tissue. High-resolution confocal imaging and immunohistochemical analysis provide ample evidence that ERbeta expression is limited almost exclusively to the ciliated epithelial cells, in contrast to ERalpha, which is widely distributed. Furthermore, within the ciliated epithelial cells, ERbeta is colocalized with beta-tubulin IV at stem portion of the cilia. We show that ERbeta2 protein expression is tightly regulated by E(2) or DPN in a time-dependent manner without changes in ERbeta1 expression. These estrogenic effects are inhibited by an ER antagonist, ICI 182,780. In addition, significant alteration of ERbeta immunoreactivity is detected only histologically in the ampullary region. Since the cilia are considered an essential determinant of tubal transport, we further demonstrate that E(2)- or DPN-induced ERbeta2 activation is associated with alterations in tubal protein expression crucial for the regulation of calcium-dependent ciliary beating. Given the coordinated regulation and interaction of ER and progesterone receptor in the cilia, we hypothesize that tubal ERbeta2 may facilitate the estrogen-mediated transport process by processing protein-protein interaction under physiological and/or pathological conditions. We show for the first time that a previously unrecognized localization of ERbeta isoform in rat fallopian tubes can combine with estrogen to individually control the expression of ER beta-isoforms in normal target tissues.
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| 3. |
- Culmsee, C., et al.
(author)
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Apoptosis-inducing factor triggered by poly(ADP-ribose) polymerase and Bid mediates neuronal cell death after oxygen-glucose deprivation and focal cerebral ischemia
- 2005
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In: J Neurosci. ; 25:44, s. 10262-72
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Journal article (peer-reviewed)abstract
- Delayed neuronal cell death occurring hours after reperfusion is a hallmark of ischemic stroke and a primary target for neuroprotective strategies. In the present study, we investigated whether apoptosis-inducing factor (AIF), a caspase-independent proapoptotic protein, is responsible for neuronal cell death after glutamate toxicity and oxygen-glucose deprivation (OGD) in vitro and after experimental stroke in vivo. AIF translocated to the nucleus in which it colocalized with DNA fragmentation and nuclear apoptotic morphology after exposure to glutamate or OGD in cultured neurons or after transient middle cerebral artery occlusion (MCAo) in mice. Small inhibitory RNA-mediated downregulation of AIF reduced glutamate- and OGD-induced neuronal apoptosis by 37 and 60%, respectively (p < 0.01). Moreover, Harlequin mutant mice, which express AIF at low levels (approximately 20% of wild-type mice), displayed smaller infarct volumes (-43%; p < 0.03) and showed dramatically reduced cell death in the ischemic penumbra after 45 min of MCAo compared with wild-type littermates. Inhibition of poly(ADP-ribose) polymerase and Bid reduced nuclear AIF translocation. These results provide the first evidence for a causal role of AIF in ischemic neuronal cell death. Therefore, caspase-independent cell death signaling may provide a promising novel target for therapeutic interventions in cerebrovascular diseases.
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| 4. |
- Johansson, Inger, 1962, et al.
(author)
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Proliferative and protective effects of growth hormone secretagogues on adult rat hippocampal progenitor cells.
- 2008
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In: Endocrinology. - : The Endocrine Society. - 0013-7227 .- 1945-7170. ; 149:5, s. 2191-9
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Journal article (peer-reviewed)abstract
- Progenitor cells in the subgranular zone of the hippocampus may be of significance for functional recovery after various injuries because they have a regenerative potential to form new neuronal cells. The hippocampus has been shown to express the GH secretagogue (GHS) receptor 1a, and recent studies suggest GHS to both promote neurogenesis and have neuroprotective effects. The aim of the present study was to investigate whether GHS could stimulate cellular proliferation and exert cell protective effects in adult rat hippocampal progenitor (AHP) cells. Both hexarelin and ghrelin stimulated increased incorporation of (3)H-thymidine, indicating an increased cell proliferation. Furthermore, hexarelin, but not ghrelin, showed protection against growth factor deprivation-induced apoptosis, as measured by annexin V binding and caspase-3 activity and also against necrosis, as measured by lactate dehydrogenase release. Hexarelin activated the MAPK and the phosphatidylinositol 3-kinase/Akt pathways, whereas ghrelin activated only the MAPK pathway. AHP cells did not express the GHS receptor 1a, but binding studies could show specific binding of both hexarelin and ghrelin, suggesting effects to be mediated by an alternative GHS receptor subtype. In conclusion, our results suggest a differential effect of hexarelin and ghrelin in AHP cells. We have demonstrated stimulation of (3)H-thymidine incorporation with both hexarelin and ghrelin. Hexarelin, but not ghrelin, also showed a significant inhibition of apoptosis and necrosis. These results suggest a novel cell protective and proliferative role for GHS in the central nervous system.
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| 5. |
- Li, T, et al.
(author)
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Systemic hypothermia induced within 10 hours after birth improved neurological outcome in newborns with hypoxic-ischemic encephalopathy
- 2009
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In: Hospital Practice. - : Informa UK Limited. - 0018-5809 .- 2154-8331 .- 2377-1003. ; 37:1, s. 1-6
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Journal article (peer-reviewed)abstract
- Objective: To evaluate the efficacy of systemic hypothermia when applied within 10 hours after birth to neonates with hypoxic-ischemic encephalopathy (HIE). Study Design: Ninety-three term infants with moderate-to-severe HIE were randomly assigned to either systemic hypothermia (n = 46) or conventional treatment (n = 47). Hypothermia was induced within 10 hours after birth, decreasing rectal temperature to 33.5°C for 72 hours, followed by slow rewarming to 36.5°C. Neurodevelopmental outcome was assessed at 18 months old. The primary outcome was death or moderate-to-severe disability. Results: Outcome data were available for 82 infants. Death or moderate-to-severe disability occurred in 21 of 44 infants (47.7%) in the control group and in 7 of 38 infants (18.4%) in the hypothermia group (P = 0.01) at 18 months. The primary outcome was not different whether hypothermia was started within 6 hours or 6 to 10 hours after birth. Subgroup analysis suggested that systemic hypothermia improved long-term outcome only in infants with moderate HIE (P = 0.009), but not in those with severe HIE. No severe hypothermia-related adverse events were observed. Conclusion: Systemic hypothermia reduced the risk of disability in infants with moderate HIE, in accordance with earlier studies. Hypothermia was induced within 6 hours in most infants, but delaying the onset to 6 to 10 hours after birth did not negatively affect primary outcome. Further studies with a large number of patients are needed to confirm that delayed cooling is equally effective.
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| 6. |
- Naylor, Andrew Stuart, 1977, et al.
(author)
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Voluntary running rescues adult hippocampal neurogenesis after irradiation of the young mouse brain.
- 2008
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In: Proceedings of the National Academy of Sciences of the United States of America. - : Proceedings of the National Academy of Sciences. - 1091-6490. ; 105:38, s. 14632-7
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Journal article (peer-reviewed)abstract
- Cranial radiation therapy is commonly used in the treatment of childhood cancers. It is associated with cognitive impairments tentatively linked to the hippocampus, a neurogenic region of the brain important in memory function and learning. Hippocampal neurogenesis is positively regulated by voluntary exercise, which is also known to improve hippocampal-dependent cognitive functions. In this work, we irradiated the brains of C57/BL6 mice on postnatal day 9 and evaluated both the acute effects of irradiation and the effects of voluntary running on hippocampal neurogenesis and behavior 3 months after irradiation. Voluntary running significantly restored precursor cell and neurogenesis levels after a clinically relevant, moderate dose of irradiation. We also found that irradiation perturbed the structural integration of immature neurons in the hippocampus and that this was reversed by voluntary exercise. Furthermore, irradiation-induced behavior alterations observed in the open-field test were ameliorated. Together, these results clearly demonstrate the usefulness of physical exercise for functional and structural recovery from radiation-induced injury to the juvenile brain, and they suggest that exercise should be evaluated in rehabilitation therapy of childhood cancer survivors.
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| 7. |
- Oltean, Mihai, 1976, et al.
(author)
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Donor pretreatment with FK506 reduces reperfusion injury and accelerates intestinal graft recovery in rats
- 2007
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In: Surgery. - : Elsevier BV. - 0039-6060. ; 141:5, s. 667-77
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Journal article (peer-reviewed)abstract
- BACKGROUND: FK506 alleviates warm ischemia-reperfusion injury, but it remains unknown if such protection is manifest after cold storage and transplantation. We studied the early outcome after transplantation of intestines from donors pretreated with FK506 compared to grafts from controls treated with saline (154 mM NaCl). METHODS: Sprague-Dawley rats received 0.3 mg/kg FK506 or saline intravenously 6 hours before graft retrieval. The small bowel was harvested, stored for 3 hours, and then transplanted heterotopically. Samples were taken after preservation and at 20 minutes, 6 hours, 12 hours, and 24 hours after reperfusion. Heat shock protein 72 (Hsp72) and iintercellular adhesion molecule (ICAM)-1 expression and nuclear factor kappaB (NF-kappaB) activation were assessed via Western blots and eelectrophoretic mobility shift assay (EMSA), respectively. Dissacharidase activity and enterocyte proliferation rate were also studied. RESULTS: Preservation injury was similar between groups, but pretreated grafts had better morphology already 20 minutes after reperfusion. Control grafts always had thinner mucosa and more PMN infiltration. Hsp72 expression was greater in pretreated grafts. ICAM-1 was absent after harvesting, preservation, and immediately after reperfusion but increased in control grafts at the later time points. Control grafts showed a biphasic NF-kappaB activation pattern, whereas NF-kappaB activation was inhibited effectively in pretreated grafts. Dissacharidase activity decreased during the first 6 hours after reperfusion but recovered within 24 hours in pretreated grafts but not in control grafts. Earlier enterocyte proliferation was observed in pretreated grafts. CONCLUSIONS: FK506 donor pretreatment reduced graft proinflammatory activation and neutrophil inflammation. Pretreated groups revealed a milder reperfusion injury and accelerated morphologic and functional recovery. The mechanisms involved appear to involve Hsp72 upregulation and NF-kappaB inhibition.
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| 8. |
- Oltean, Mihai, 1976, et al.
(author)
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FK506 donor pretreatment improves intestinal graft microcirculation and morphology by concurrent inhibition of early NF-kappaB activation and augmented HSP72 synthesis
- 2005
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In: Transplant Proc. - : Elsevier BV. - 0041-1345. ; 37:4, s. 1931-3
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Journal article (peer-reviewed)abstract
- FK506 protects against ischemia-reperfusion injury but the mechanisms remain unclear. We investigated the impact of donor pretreatment using FK506 on graft microcirculation and morphology after intestinal transplantation. FK506 was given intravenously to SD rats (0.3 mg/kg) 6 hours before graft harvesting while controls received saline (n = 7/group). Grafts were stored for 3 hours in saline, then transplanted. Preservation induced similar lesions in both groups, but pretreated grafts showed better morphology than controls at 20 minutes after reperfusion. Six hours post-reperfusion, preconditioned grafts revealed near-normal morphology, whereas controls showed short villi, denuded areas, and intense inflammation. Pretreated grafts displayed a lower apoptotic rate and reduced caspase-3 activity. Hsp72 expression was enhanced in preconditioned grafts at harvesting, after preservation, and 20 minutes post-reperfusion compared to controls. Control grafts showed intranuclear p65 (activation of NFkappaB) at 20 minutes post-reperfusion; whereas pretreated grafts displayed no intranuclear p65. However, at 6 hours, comparable intranuclear p65 levels were found in both groups. ICAM-1 was low in both groups after preservation and early post-reperfusion, but greatly increased in controls at 6 hours post-reperfusion. In contrast, pretreated grafts continued to lack ICAM-1. Microvascular perfusion was comparable at 20 minutes. Six hours later, pretreated grafts had 30% increased perfusion, while in controls it was slightly decreased. FK506 alleviated reperfusion injury by blocking NF-kappaB activation and ICAM-1 transcription, thus decreasing endothelial activation and improving the microcirculation. It also induces Hsp72, therefore inhibiting apoptosis and accelerating morphologic restoration.
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| 9. |
- Oltean, Mihai, 1976, et al.
(author)
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Reduced liver injury and cytokine release after transplantation of preconditioned intestines.
- 2009
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In: The Journal of surgical research. - : Elsevier BV. - 1095-8673 .- 0022-4804. ; 154:1, s. 30-7
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Journal article (peer-reviewed)abstract
- BACKGROUND: The postischemic intestine liberates pro-inflammatory mediators (cytokines, lipopolysaccharide [LPS], free radicals) proportional with the local injury that may trigger a systemic inflammatory response and multi-system organ failure. Previously, intestines from donors receiving Tacrolimus revealed improved morphology and abrogated nuclear factor kappa B (NF-kappaB) activation. Because of its pivotal role in inflammation, we investigated if NF-kappaB intragraft inhibition influences the posttransplant inflammatory response and remote organ injury. MATERIALS AND METHODS: Donor Sprague Dawley rats received tacrolimus (0.3 mg/kg) or saline i.v. 6 h before graft harvest. The intestines were preserved for 3 h and then transplanted heterotopically. Hepatic microcirculation was assessed at 20 min, 6 h, 12 h, or 24 h post-reperfusion (postR) using laser-Doppler flowmetry (n = 10/group). Blood pressure measurements and liver sampling were performed at 6, 12, or 24 h postR. Blood samples were obtained at 1, 3, 6, 12, and 24 h postR. Hepatic intercellular adhesion molecule 1 (ICAM-1) expression, caspase-3 and -9 activity, and circulating tumor necrosis factor alpha (TNF-alpha), interleukin-1beta (IL-1beta), IL-6, and LPS were studied. RESULTS: Pretreated graft (PG) recipients had superior cardiovascular parameters at 6 and 12 h postR, while liver perfusion was similar between groups at all time points. Recipients of PG had lower transaminase levels and ICAM-1 liver expression. Liver caspase 3 and 9 activity were similar at 6 and 12 h but increased at 24 h in both groups. At every time point, circulating tumor necrosis factor alph, IL-1beta, and IL-6 were lower in animals receiving PG. LPS was found increased only at the last time point. CONCLUSIONS: Transplantation of tacrolimus-pretreated intestines triggered a milder inflammatory response and decreased liver injury early posttransplantation compared with untreated grafts. Cytokines, but not neutrophils, hypoperfusion, or LPS may underlie the dysfunction.
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| 10. |
- Oltean, Mihai, 1976, et al.
(author)
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Transplantation of preconditioned intestinal grafts is associated with lower inflammatory activation and remote organ injury in rats
- 2006
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In: Transplant Proc. - : Elsevier BV. - 0041-1345. ; 38:6, s. 1775-8
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Journal article (peer-reviewed)abstract
- Reperfused grafts--particularly the intestine--release free radicals and cytokines into the systemic circulation. The type of discharge, which is greatly dependent on the local injury, may also induce inflammatory activation in distant organs and leading to multiple system and organ failure. It has been suggested that intestinal grafts from tacrolimus (TRL)-pretreated donors show improved morphology and microcirculation. We studied whether transplantation of intestines from TRL-pretreated donors influenced inflammatory response and remote organ injury posttransplantation. Donor Sprague Dawley rats received TRL or saline (controls) intravenously at 6 hours prior to graft harvest. The intestinal grafts were preserved in saline for 3 hours before transplantation. At 6 and 12 hours postreperfusion hepatic and renal cortical microcirculation were assessed using laser-Doppler flowmetry (n = 8-12 per group). Blood pressure was measured; liver, kidney, and serum samples were obtained. We analyzed hepatic and renal ICAM-1 expression and caspase-3-like activity as well as plasma content of tumor necrosis factor-alpha and interleukin-6. Pretreated graft recipients had higher mean arterial pressure (82 +/- 10 vs 51 +/- 17 mm Hg, P < .05) and renal perfusion at 6 hours whereas liver perfusion was similar at both 6 and 12 hours. Liver and renal functions were also superior among recipients of pretreated grafts. Both caspase-3-like activity and ICAM-1 expression in liver and kidney were lower in pretreated graft recipients. Plasma IL-6 levels were lower in animals receiving pretreated grafts. Transplantation of intestines from TRL-pretreated donors was followed by a lower systemic inflammatory response, improved organ function and decreased remote injury early posttransplantation compared with animals receiving grafts from untreated donors.
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