Terpenoid-rich Elettaria cardamomum extract prevents Alzheimer-like alterations induced in diabetic rats via inhibition of GSK3ß activity, oxidative stress and pro-inflammatory cytokines.

PURPOSE: Recent studies suggested that the non-familiar form of Alzheimer's disease (AD) could be consequence of metabolic syndrome and neuroinflammation. Elettaria cardamomum extract (EC) has exhibited antidiabetic, antioxidant and anti-inflammatory properties. This research was conducted to evaluate the effects of EC on AD-like alterations in rats induced by high fructose and high fat diet coupled with a single small dose of STZ (25 mg/kg) (T2DM rats). METHODS: Phytochemical analysis was carried out. Behavioral tests, immunohistochemical examination, biochemical analysis and gene expression determination were performed in treated and controls rats. RESULTS: The majority of EC compounds were terpenoids. EC extract administration for 8 weeks attenuated AD-like alterations. It reversed a T2DM-induced decline in cognitive functions in passive avoidance task and Morris water maze test. It significantly lowered the elevated hippocampal level of AChE activity and caspase-3 activity, an indicator of degeneration in T2DM rats Also, it reduced the accumulation of Aß and p-tau in the brain of T2DM rats. Furthermore, it elevated the suppressed glutamate receptor expression (AMPA GluR1 subunit and NMDA receptor subunits NR1, NR2A, NR2B). EC treatment reduced hippocampal lipid peroxidation marker malondialdehyde (MDA) and augmented antioxidant defensive system, including superoxide dismutase (SOD) and reduced glutathione (GSH). Meanwhile, it lowered hippocampal TNFα, IL ß1but not IL6 and reduced GSK-3ß in brainT2D rats. CONCLUSION: EC treatment could ameliorate AD-like alterations in T2DM rats through activation of blunted insulin signal transduction in the brain, attenuation of associated oxidative stress and neuroinflammation.

The low-affinity nerve growth factor receptor p75NTR identifies a transient stem cell-like state in oral squamous cell carcinoma cells.

BACKGROUND: Although several markers have been used for enrichment of cells with stem cell-like properties in oral squamous cell carcinoma (OSCC), isolation of a pure subpopulation is still a challenging task. Normal oral and esophageal keratinocyte stem cells have been previously isolated using the low-affinity nerve growth factor receptor p75NTR. OBJECTIVE: To investigate the potential of p75NTR as a marker for identification and isolation of oral cancer cells with stem cell-like properties. METHODS: Subpopulations of cells with high or low expression of p75NTR were sorted from OSCC-derived cells and compared for sphere/colony formation, in vivo tumor formation ability, expression of stem cell-related molecules, cell cycle distribution and drug resistance. RESULTS: p75NTR(High) cells exhibited statistically significant higher stem cell properties than p75NTR(Low) cells in all assays performed. Nevertheless, p75NTR(Low) subpopulation did also exhibit some stem cell features, but to a lesser extent. Propagation of p75NTR(Low) cells for several passages in culture showed that the expression of p75NTR could rise spontaneously. This finding was also supported by the similar expression of p75NTR by the xenografts generated by both subpopulations in NOD\SCID IL2Rg(null) mice. CONCLUSION: p75NTR can be used for isolating a subpopulation enriched for cells with stem cell-like properties in OSCC. De novo generation of p75NTR(High) cells from p75NTR(Low) cells suggests either that there is another subpopulation with stem cell features within the p75NTR(Low) cells, or that the p75NTR(Low) cells can dedifferentiate due to a contextually regulated equilibrium between stem cell-like cells and transit-amplifying neoplastic progenitors.