Vascular endothelial growth factor (VEGF) is an angiogenic protein with therapeutic potential in ischemic disorders, including stroke. VEGF confers neuroprotection and promotes neurogenesis and cerebral angiogenesis, but the manner in which these effects may interact in the ischemic brain is poorly understood. We produced focal cerebral ischemia by middle cerebral artery occlusion for 90 minutes in the adult rat brain and measured infarct size, neurological function, BrdU labeling of neuroproliferative zones, and vWF-immunoreactive vascular profiles, without and with intracerebroventricular administration of VEGF on days 1–3 of reperfusion. VEGF reduced infarct size, improved neurological performance, enhanced the delayed survival of newborn neurons in the dentate gyrus and subventricular zone, and stimulated angiogenesis in the striatal ischemic penumbra, but not the dentate gyrus. We conclude that in the ischemic brain VEGF exerts an acute neuroprotective effect, as well as longer latency effects on survival of new neurons and on angiogenesis, and that these effects appear to operate independently. VEGF may, therefore, improve histological and functional outcome from stroke through multiple mechanisms.
Yunjuan Sun, Kunlin Jin, Lin Xie, Jocelyn Childs, Xiao Ou Mao, Anna Logvinova, David A. Greenberg
The physiologic role of the μ opioid receptor (MOR) in gut nociception, motility, and secretion is well established. To evaluate whether MOR may also be involved in controlling gut inflammation, we first showed that subcutaneous administration of selective peripheral MOR agonists, named DALDA and DAMGO, significantly reduces inflammation in two experimental models of colitis induced by administration of 2,4,6-trinitrobenzene sulfonic acid (TNBS) or peripheral expansion of CD4+ T cells in mice. This therapeutic effect was almost completely abolished by concomitant administration of the opioid antagonist naloxone. Evidence of a genetic role for MOR in the control of gut inflammation was provided by showing that MOR-deficient mice were highly susceptible to colon inflammation, with a 50% mortality rate occurring 3 days after TNBS administration. The mechanistic basis of these observations suggests that the anti-inflammatory effects of MOR in the colon are mediated through the regulation of cytokine production and T cell proliferation, two important immunologic events required for the development of colon inflammation in mice and patients with inflammatory bowel disease (IBD). These data provide evidence that MOR plays a role in the control of gut inflammation and suggest that MOR agonists might be new therapeutic molecules in IBD.
David Philippe, Laurent Dubuquoy, Hervé Groux, Valérie Brun, Myriam Tran Van Chuoï-Mariot, Claire Gaveriaux-Ruff, Jean-Frédéric Colombel, Brigitte L. Kieffer, Pierre Desreumaux
EGF promotes proliferation and migration of stem/progenitor cells in the normal adult brain. The effect of epidermal growth factor on neurogenesis in ischemic brain is unknown, however. Here we show that intraventricular administration of EGF and albumin augments 100-fold neuronal replacement in the injured adult mouse striatum after cerebral ischemia. Newly born immature neurons migrate into the ischemic lesion and differentiate into mature parvalbumin-expressing neurons, replacing more than 20% of the interneurons lost by 13 weeks after ischemia and representing 2% of the total BrdU-labeled cells. These data suggest that administration of EGF and albumin could be used to manipulate endogenous neurogenesis in the injured brain and to promote brain self-repair.
Tetsuyuki Teramoto, Jianhua Qiu, Jean-Christophe Plumier, Michael A. Moskowitz
Deletions in the DAP12 gene in humans result in Nasu-Hakola disease, characterized by a combination of bone fractures and psychotic symptoms similar to schizophrenia, rapidly progressing to presenile dementia. However, it is not known why these disorders develop upon deficiency in DAP12, an immunoreceptor signal activator protein initially identified in the immune system. Here we show that DAP12-deficient (DAP12–/–) mice develop an increased bone mass (osteopetrosis) and a reduction of myelin (hypomyelinosis) accentuated in the thalamus. In vitro osteoclast induction from DAP12–/– bone marrow cells yielded immature cells with attenuated bone resorption activity. Moreover, immature oligodendrocytes were arrested in the vicinity of the thalamus, suggesting that the primary defects in DAP12–/– mice are the developmental arrest of osteoclasts and oligodendrocytes. In addition, the mutant mice also showed synaptic degeneration, impaired prepulse inhibition, which is commonly observed in several neuropsychiatric diseases in humans including schizophrenia, and aberrant electrophysiological profiles in the thalami. These results provide a molecular basis for a unique combination of skeletal and psychotic characteristics of Nasu-Hakola disease as well as for schizophrenia and presenile dementia.
Tomonori Kaifu, Jin Nakahara, Masanori Inui, Kenichi Mishima, Toshihiko Momiyama, Mitsuji Kaji, Akiko Sugahara, Hisami Koito, Azusa Ujike-Asai, Akira Nakamura, Kiyoshi Kanazawa, Kyoko Tan-Takeuchi, Katsunori Iwasaki, Wayne M. Yokoyama, Akira Kudo, Michihiro Fujiwara, Hiroaki Asou, Toshiyuki Takai
Manuela Neumann, Philipp J. Kahle, Benoit I. Giasson, Laurence Ozmen, Edilio Borroni, Will Spooren, Veronika Müller, Sabine Odoy, Hideo Fujiwara, Masato Hasegawa, Takeshi Iwatsubo, John Q. Trojanowski, Hans A. Kretzschmar, Christian Haass
Felix Kreier, Eric Fliers, Peter J. Voshol, Corbert G. Van Eden, Louis M. Havekes, Andries Kalsbeek, Caroline L. Van Heijningen, Arja A. Sluiter, Thomas C. Mettenleiter, Johannes A. Romijn, Hans P. Sauerwein, Ruud M. Buijs
Clyde W. Hodge, Jacob Raber, Thomas McMahon, Helen Walter, Ana Maria Sanchez-Perez, M. Foster Olive, Kristin Mehmert, A. Leslie Morrow, Robert O. Messing