Neurotrophic factor mediated neuronal differentiation of human cord blood mesenchymal stem cells and their applicability to assess the developmental neurotoxicity.

Plasticity and developmental capacity of stem cells have now been established as a promising tool to restore the degenerative disorders. The linearity differentiation of human mesenchymal stem cells (hMSCs) into adipogenic, chondrogenic, osteogenic and even in neuronal subtypes has been demonstrated. The number of xenobiotics such as dexamethasone, insulin, isobutyl 1-methyle xanthine and retinoic acid has been reported for the potential to differentiate hMSCs into neuronal subtypes. But, the applicability of indigenous neurotrophic factor-nerve growth factor (NGF) has not been explored for the purpose. Thus, the present investigations were carried out to study the NGF induced neuronal differentiation of hMSCs. Following the isolation, purification and characterization of hMSCs were allowed to differentiate into neuronal subtypes under the influence of NGF (50 ng/mL). At various concentrations of NGF, the neuronal makers were analysed at both mRNA and protein levels. Cells, exposed with NGF were showing the significant and gradual increase in the neuronal markers in differentiating cells. The magnitude of expression of markers was maximum at day 4 of differentiation. NGF at 50 ng/mL concentration was found to induce neuronal differentiation of hMSCs into neuronal subtypes.

Mechanistic Insights of Astrocyte-Mediated Hyperactive Autophagy and Loss of Motor Neuron Function in SOD1L39R Linked Amyotrophic Lateral Sclerosis.

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disorder with no cure. The reports showed the role of nearby astrocytes around the motor neurons as one among the causes of the disease. However, the exact mechanistic insights are not explored so far. Thus, in the present investigations, we employed the induced pluripotent stem cells (iPSCs) of Cu/Zn-SOD1L39R linked ALS patient to convert them into the motor neurons (MNs) and astrocytes. We report that the higher expression of stress granule (SG) marker protein G3BP1, and its co-localization with the mutated Cu/Zn-SOD1L39R protein in patient's MNs and astrocytes are linked with AIF1-mediated upregulation of caspase 3/7 and hyper activated autophagy. We also observe the astrocyte-mediated non-cell autonomous neurotoxicity on MNs in ALS. The secretome of the patient's iPSC-derived astrocytes exerts significant oxidative stress in MNs. The findings suggest the hyperactive status of autophagy in MNs, as witnessed by the co-distribution of LAMP1, P62 and LC3 I/II with the autolysosomes. Conversely, the secretome of normal astrocytes has shown neuroprotection in patient's iPSC-derived MNs. The whole-cell patch-clamp assay confirms our findings at a physiological functional level in MNs. Perhaps for the first time, we are reporting that the MN degeneration in ALS triggered by the hyper-activation of autophagy and induced apoptosis in both cell-autonomous and non-cell autonomous conditions.

Structure-Activity Relationship Studies on Holy Basil (Ocimum sanctum L.) Based Flavonoid Orientin and its Analogue for Cytotoxic Activity in Liver Cancer Cell Line HepG2.

O. sanctum L. (O. tenuiflorum) is an important sacred medicinal plant of India known as Holy Basil or Tulsi. The chemical composition of volatile oil is highly complex and comprises high ratio of phenylpropanoids and terpenes, and some phenolic compound or flavonoids such as orientin and vicenin. These minor flavonoids are known to be antioxidant and anticancer in nature. Orientin reported as potential anticancer agent due to anti-proliferative activity on human liver cancer cell line HepG2, but its mechanism of action is not fully explored. In the present work an in-silico structure-activity relationship study on orientin was performed and built a pharmacophore mapping and QSAR model to screen out the potential structurally similar analogues from chemical database of Discovery Studio (DSv3.5, Accelrys, USA) as potential anticancer agent. Analogue fenofibryl glucuronide was selected for in vitro cytotoxic/anticancer activity evaluation through MTT assay. Binding affinity and mode of action of orientin and its analogue were explored through molecular docking studies on quinone oxidoreductase, a potential target of flavonoids. Contrary to the assumption, in vitro results showed only 41% cell death at 202.389 µM concentration (at 96 hrs). Therefore, we concluded that the selected orientin analogue fenofibryl glucuronide was non-cytotoxic/non-anti-carcinogenic up to 100 µg/ml (202.389 µM) concentrations for a long term exposure i.e., till 96 hrs in human cancer cells of HepG2. We concluded that orientin and its analogue fenofibryl glucuronide as pure compound showed no activity or less cytotoxicity activity on liver cancer cell line HepG2.

Differential responses of Trans-Resveratrol on proliferation of neural progenitor cells and aged rat hippocampal neurogenesis.

The plethora of literature has supported the potential benefits of Resveratrol (RV) as a life-extending as well as an anticancer compound. However, these two functional discrepancies resulted at different concentration ranges. Likewise, the role of Resveratrol on adult neurogenesis still remains controversial and less understood despite its well documented health benefits. To gather insight into the biological effects of RV on neurogenesis, we evaluated the possible effects of the compound on the proliferation and survival of neural progenitor cells (NPCs) in culture, and in the hippocampus of aged rats. Resveratrol exerted biphasic effects on NPCs; low concentrations (10 µM) stimulated cell proliferation mediated by increased phosphorylation of extracellular signal-regulated kinases (ERKs) and p38 kinases, whereas high concentrations (>20 µM) exhibited inhibitory effects. Administration of Resveratrol (20 mg/kg body weight) to adult rats significantly increased the number of newly generated cells in the hippocampus, with upregulation of p-CREB and SIRT1 proteins implicated in neuronal survival and lifespan extension respectively. We have successfully demonstrated that Resveratrol exhibits dose dependent discrepancies and at a lower concentration can have a positive impact on the proliferation, survival of NPCs and aged rat hippocampal neurogenesis implicating its potential as a candidate for restorative therapies against age related disorders.