Abstract: The neurogenic potential of many herbal extracts used
in Indian medicine is hitherto unknown. Extracts derived from
Clitoria ternatea Linn have been used in Indian Ayurvedic system of
medicine as an ingredient of “Medhya rasayana", consumed for
improving memory and longevity in humans and also in treatment of
various neurological disorders. Our earlier experimental studies with
oral intubation of Clitoria ternatea aqueous root extract (CTR) had
shown significant enhancement of learning and memory in postnatal
and young adult Wistar rats. The present study was designed to
elucidate the in vitro effects of 200ng/ml of CTR on proliferation,
differentiation and growth of anterior subventricular zone neural
stem cells (aSVZ NSC-s) derived from prenatal and postnatal rat
pups. Results show significant increase in proliferation and growth of
neurospheres and increase in the yield of differentiated neurons of
aSVZ neural precursor cells (aSVZNPC-s) at 7 days in vitro when
treated with 200ng/ml of CTR as compared to age matched control.
Results indicate that CTR has growth promoting neurogenic effect on
aSVZ neural stem cells and their survival similar to neurotrophic
factors like Survivin, Neuregulin 1, FGF-2, BDNF possibly the basis
for enhanced learning and memory.
Abstract: MicroRNAs are an important class of gene expression
regulators that are involved in many biological processes including
embryogenesis. miR-125b is a conserved microRNA that is enriched
in the nervous system. We have previously reported the function of
miR-125b in neuronal differentiation of human cell lines. We also
discovered the function of miR-125b in regulating p53 in human and
zebrafish. Here we further characterize the brain defects in zebrafish
embryos injected with morpholinos against miR-125b. Our data
confirm the essential role of miR-125b in brain morphogenesis
particularly in maintaining the balance between proliferation, cell
death and differentiation. We identified lunatic fringe (lfng) as an
additional target of miR-125b in human and zebrafish and suggest
that lfng may mediate the function of miR-125b in neurogenesis.
Together, this report reveals new insights into the function of miR-
125b during neural development of zebrafish.
Abstract: Bone marrow-derived stem cells have been widely
studied as an alternative source of stem cells. Mesenchymal stem
cells (MSCs) were mostly investigated and studies showed MSCs can
promote neurogenesis. Little is known about the non-mesenchymal
mononuclear cell fraction, which contains both hematopoietic and
nonhematopoietic cells, including monocytes and endothelial
progenitor cells. This study focused on unfractionated bone marrow
mononuclear cells (BMMCs), which remained 72 h after MSCs were
adhered to the culture plates. We showed that BMMC-conditioned
medium promoted morphological changes of human SH-SY5Y
neuroblastoma cells from an epithelial-like phenotype towards a
neuron-like phenotype as indicated by an increase in neurite
outgrowth, like those observed in retinoic acid (RA)-treated cells.
The result could be explained by the effects of trophic factors
released from BMMCs, as shown in the RT-PCR results that
BMMCs expressed nerve growth factor (NGF), brain-derived
neurotrophic factor (BDNF), and ciliary neurotrophic factor (CNTF).
Similar results on the cell proliferation rate were also observed
between RA-treated cells and cells cultured in BMMC-conditioned
medium, suggesting that cells creased proliferating and differentiated
into a neuronal phenotype. Using real-time RT-PCR, a significantly
increased expression of tyrosine hydroxylase (TH) mRNA in SHSY5Y
cells indicated that BMMC-conditioned medium induced
catecholaminergic identities in differentiated SH-SY5Y cells.