Diencephalic progenitors contribute to the posterior septum through rostral migration along the hippocampal axonal pathway.

Septal nuclei are telencephalic structures associated with a variety of brain functions as part of the limbic system. The two posterior septal nuclei, the triangular septal nucleus (TS) and the bed nuclei of the anterior commissure (BAC), are involved in fear and anxiety through their projections to the medial habenular nucleus. However, the development of both the TS and BAC remains unclear. Here, we found a novel caudal origin and putative migratory stream of mouse posterior septal neurons arising from the thalamic eminence (TE), a transient developmental structure at the rostral end of the rodent diencephalon. TE-derived cells, which have glutamatergic identity, migrated rostrally and entered the telencephalic territory by passing beneath the third ventricle. Subsequently, they turned dorsally toward the posterior septum. We also observed that TS and BAC neurons in the postnatal septum were labeled with GFP by in utero electroporation into the TE, suggesting a shared origin. Furthermore, TE-derived septal neurons migrated along the fornix, an efferent pathway from the hippocampus. These results demonstrate that posterior septal neurons have a distinct extratelencephalic origin from other septal nuclei. This heterogeneous origin may contribute to neuronal diversity of the septal nuclear complex.

Naphthalene glycosides in the Thai medicinal plant Diospyros mollis.

This study evaluated methanol extracts from the leaves and branches of the Thai medicinal plant Diospyros mollis (Ebenaceae). Seven triterpenes and 22 aromatic compounds, including five new compounds, were isolated, and their structures were determined. The new compounds had the following structures: diospyrol glycoside (makluoside A, 1), 8,8'-di-O-6-ß-D-apiofuranosyl-ß-D-glucopyranosyl-6,6'-dimethyl-2,3'-binaphthalene-1-ol-1',4'- dione (makluoside B, 2), and 3-methyl-1,8- naphthalenediol glycosides (makluosides C-E, 3-5). Makluoside B is the first example of a naphthoquinone glycoside that has both a 3-methyl-1,8-naphthalenediol unit and a 5-hydroxy-7-methyl-1,4-naphthoquinone unit. The hyaluronidase inhibitory activity of the isolates was evaluated, revealing that one of the triterpene derivatives possessed moderate inhibitory activity.

Evaluation of the neuroprotective effect of minocycline in a rabbit spinal cord ischemia model.

OBJECTIVE: To investigate whether postischemic administration of minocycline attenuates hind-limb motor dysfunction and gray and white matter injuries after spinal cord ischemia. DESIGN: A prospective, randomized, laboratory investigation. SETTING: Laboratory in university, single institution. PARTICIPANTS: Male New Zealand White rabbits. INTERVENTION: Spinal cord ischemia was induced by an occlusion of the infrarenal aorta for 15 minutes. The groups were administered minocycline 1 hour after reperfusion (M-1; n = 8), minocycline 3 hours after reperfusion (M-3; n = 8), saline 1 hour after reperfusion (control [C]; n = 8), or saline and no occlusion (sham; n = 4). Minocycline was administered intravenously at 10 mg/kg 6 times at 12-hour intervals until 60 hours after the initial administration. MEASUREMENT AND MAIN RESULTS: Hind-limb motor function was assessed using the Tarlov score. For histologic assessments, gray and white matter injuries were evaluated 72 hours after reperfusion using the number of normal neurons and the percentage of areas of vacuolation, respectively. Motor function 72 hours after reperfusion was significantly better in group M-1 than in group C. The number of neurons in the anterior horn was significantly larger in group M-1 than in groups M-3 or C but did not differ significantly between groups M-3 and C. No significant difference was noted in the percentage of areas of vacuolation among the ischemia groups. CONCLUSIONS: Minocycline administration beginning at 1 hour after reperfusion improved hind-limb motor dysfunction and attenuated gray matter injury in a rabbit spinal cord ischemia model.

Parvalbumin neurons in the forebrain as revealed by parvalbumin-Cre transgenic mice.

Neurons expressing the calcium-binding protein parvalbumin (PV) constitute an abundant subpopulation of GABAergic neurons in the cerebral cortex. However, PV is not unique to the GABAergic neurons of the forebrain, but is also expressed in a small number of pyramidal neurons and in a large number of thalamic neurons. In order to summarize the PV neurons in the forebrain, we employed the PV-Cre transgenic mice in the present study. In the progeny of crossbreed between PV-Cre mice and GFP-Cre reporter mice, we found that the GFP-positive neurons include many excitatory neurons in the neocortex and the thalamus as well as GABAergic neurons in the cerebral cortex and basal ganglia. All the reported PV-positive GABAergic neurons in the cerebral cortex and the basal ganglia seemed to be included in the GFP-positive cells. We found GFP-positive layer V pyramidal neurons inhabit a broader neocortical area than was previously reported. They were located in the primary somatosensory, motor, and visual areas. The somatosensory area of the neocortex contained the greatest number of PV-positive pyramidal neurons. A large number of thalamic relay neurons and virtually all the reticular thalamic neurons appeared as GFP-positive. Thalamic relay nucleus and a neocortical area for the same modality corresponded and seemed to contain a characteristic amount of PV-positive excitatory neurons.