Search PubMed⌕ Search

Biomedical subjects

Cesar V Borlongan

Publications and source records attributed to Cesar V Borlongan.

24 records · Page 2Linked to original sources

Adrenomedullin gene delivery protects against cerebral ischemic injury by promoting astrocyte migration and survival.

Adrenomedullin (AM) has been shown to protect against ischemia/reperfusion-induced myocardial infarction and apoptosis. In the present study, we examined the potential neuroprotective action of delayed AM gene transfer in cerebral ischemia. Three days after a 1-hr occlusion of the middle cerebral artery (MCAO), rats were injected intravenously with adenovirus harboring human AM cDNA. The experiment was terminated 7 days after MCAO. AM gene transfer significantly reduced cerebral infarct size compared with that of rats before virus injection and compared with that of rats injected with control virus. The expression of recombinant human AM was identified in ischemic brain by immunostaining. Morphological analyses showed that AM gene transfer enhanced the survival and migration of astrocytes into the ischemic core. Cerebral ischemia markedly increased astrocyte apoptosis, and AM gene delivery significantly reduced apoptosis to near normal levels as seen in sham control rats. Similarly, in primary cultured astrocytes, AM stimulated cell migration and inhibited hypoxia/reoxygenation-induced apoptosis. The effects of AM on both migration and apoptosis were abolished by calcitonin gene-related peptide [CGRP(8-37)], an AM receptor antagonist. Enhanced cell survival after AM gene transfer was accompanied by markedly increased cerebral nitric oxide and Bcl-2 levels, as well as Akt and GSK-3beta phosphorylation, but reduced NADPH oxidase activity and superoxide production. Inactivation of GSK-3beta by phosphorylation led to reduced GSK-3beta activity and caspase- 3 activation. These results indicate that exogenous AM provides neuroprotection against cerebral ischemia injury by enhancing astrocyte survival and migration and inhibiting apoptosis through suppression of oxidative stress-mediated signaling events.

Adrenomedullin↗

Transplantation of human umbilical cord blood cells in the repair of CNS diseases.

Cell transplantation therapies have been used to treat certain neurodegenerative diseases such as Parkinson's and Huntington's disease. However, ethical concerns over the use of fetal tissues, and the inherent complexities of standardising the procurement, processing and transplantation methods of this tissue, have prompted the search for a source of cells that have less ethical stigmatisations, are readily available and can be easily standardised. Several sources of human cells that meet these principles have been under investigation. Cells from human umbilical cord blood (HUCB) are one source that is consistent with these principles; therefore, they have become of great interest in the field of cellular repair/replacement for the treatment of CNS diseases and injury. This review will focus on the advantages of HUCB cells as a source for cellular transplantation therapies, recent studies that have examined the potential of these cells in vitro to be directed towards neural phenotypes, and in vivo studies that have investigated the functional recovery of animals in a number of models of CNS injury and disease following administration of HUCB cells.

Animals↗

Healing a broken heart with stem cells.

We discuss here the rapid progress of stem cell therapy in myocardial infarction. In particular, we focus on the issue of transdifferentiation as a "hallmark" of the stem cell's potential to replace damaged cells of the heart. A study by Henning and colleagues in this issue of Cell Transplantation supports the alternative notion of a nontransdifferentiation-mediated protection of the heart as an equally robust mechanism underlying the therapeutic potential of stem cells.

Animals↗

Kallikrein gene transfer protects against ischemic stroke by promoting glial cell migration and inhibiting apoptosis.

Kallikrein/kinin has been shown to protect against ischemia/reperfusion-induced myocardial infarction and apoptosis. In the present study, we examined the potential neuroprotective action of kallikrein gene transfer in cerebral ischemia. Adult, male Sprague-Dawley rats were subjected to a 1-hour occlusion of the middle cerebral artery followed by intracerebroventricular injection of adenovirus harboring either the human tissue kallikrein gene or the luciferase gene. Kallikrein gene transfer significantly reduced ischemia-induced locomotor deficit scores and cerebral infarction after cerebral ischemia injury. Expression of recombinant human tissue kallikrein was identified and localized in monocytes/macrophages of rat ischemic brain by double immunostaining. Morphological analyses showed that kallikrein gene transfer enhanced the survival and migration of glial cells into the ischemic penumbra and core, as identified by immunostaining with glial fibrillary acidic protein. Cerebral ischemia markedly increased apoptotic cells, and kallikrein gene delivery reduced apoptosis to near-normal levels as seen in sham control rats. In primary cultured glial cells, kinin stimulated cell migration but inhibited hypoxia/reoxygenation-induced apoptosis in a dose-dependent manner. The effects of kinin on both migration and apoptosis were abolished by icatibant, a bradykinin B2 receptor antagonist. Enhanced cell survival after kallikrein gene transfer occurred in conjunction with markedly increased cerebral nitric oxide levels and phospho-Akt and Bcl-2 levels but reduced caspase-3 activation, NAD(P)H oxidase activity, and superoxide production. These results indicate that kallikrein gene transfer provides neuroprotection against cerebral ischemia injury by enhancing glial cell survival and migration and inhibiting apoptosis through suppression of oxidative stress and activation of the Akt-Bcl-2 signaling pathway.

Adenoviridae↗