MASH1 induces neuron transdifferentiation of adrenal medulla chromaffin cells / 中南大学学报(医学版)

OBJECTIVES@#Nerve growth factor (NGF) induces neuron transdifferentiation of adrenal medulla chromaffin cells (AMCCs) and consequently downregulates the secretion of epinephrine (EPI), which may be involved in the pathogenesis of bronchial asthma. Mammalian achaete scute-homologous 1 (MASH1), a key regulator of neurogenesis in the nervous system, has been proved to be elevated in AMCCs with neuron transdifferentiation in vivo. This study aims to explore the role of MASH1 in the process of neuron transdifferentiation of AMCCs and the mechanisms.@*METHODS@#Rat AMCCs were isolated and cultured. AMCCs were transfected with siMASH1 or MASH1 overexpression plasmid, then were stimulated with NGF and/or dexamethasone, PD98059 (a MAPK kinase-1 inhibitor) for 48 hours. Morphological changes were observed using light and electron microscope. Phenylethanolamine-N-methyltransferase (PNMT, the key enzyme for epinephrine synthesis) and tyrosine hydroxylase were detected by immunofluorescence. Western blotting was used to test the protein levels of PNMT, MASH1, peripherin (neuronal markers), extracellular regulated protein kinases (ERK), phosphorylated extracellular regulated protein kinases (pERK), and JMJD3. Real-time RT-PCR was applied to analyze the mRNA levels of MASH1 and JMJD3. EPI levels in the cellular supernatant were measured using ELISA.@*RESULTS@#Cells with both tyrosine hydroxylase and PNMT positive by immunofluorescence were proved to be AMCCs. Exposure to NGF, AMCCs exhibited neurite-like processes concomitant with increases in pERK/ERK, peripherin, and MASH1 levels (all P<0.05). Additionally, impairment of endocrine phenotype was proved by a signifcant decrease in the PNMT level and the secretion of EPI from AMCCs (all P<0.01). MASH1 interference reversed the effect of NGF, causing increases in the levels of PNMT and EPI, conversely reduced the peripherin level and cell processes (all P<0.01). MASH1 overexpression significantly increased the number of cell processes and peripherin level, while decreased the levels of PNMT and EPI (all P<0.01). Compared with the NGF group, the levels of MASH1, JMJD3 protein and mRNA in AMCCs in the NGF+PD98059 group were decreased (all P<0.05). After treatment with PD98059 and dexamethasone, the effect of NGF on promoting the transdifferentiation of AMCCs was inhibited, and the number of cell processes and EPI levels were decreased (both P<0.05). In addition, the activity of the pERK/MASH1 pathway activated by NGF was also inhibited.@*CONCLUSIONS@#MASH1 is the key factor in neuron transdifferentiation of AMCCs. NGF-induced neuron transdifferentiation is probably mediated via pERK/MASH1 signaling.

Antibacterial Properties of the Predominant Microorganisms Isolated from Fermenting Cassava Tubers during fufu Production against Selected Enteropathogenic Bacteria

Aim: This research investigated the antibacterial activities of the predominant microorganisms isolated from fermenting cassava mash during fufu production against selected enteropathogenic bacteria. Methodology: Microbiological analysis was carried out on the mash on daily basis during the three-day fermentation period. The pH, TTA and temperature of the fufu were also evaluated. The antibacterial activities of dominant microorganisms from the mash were assayed against the isolated microorganisms and test isolates using disc and agar diffusion methods. Results: The bacteria isolated from the fermenting mash include Bacillus subtilis, Lactobacillus fermentum, L. plantarum, Pediococcus acidilactici, Micrococcus luteus and Staphylococcus aureus while the fungi were Aspergillus flavus, A. niger, A. fumigatus, Geotrichum candidum, Penicillium expansum and Rhizospus stolonifer. The predominant microorganisms were L. plantarum, L. mesenteroides, A. niger, A. fumigatus and G. candidum. The total bacterial, lactic acid bacterial and fungal counts increased from 2.5X105 cfu/ml, 2.0X105 cfu/ml and 1.5X103 cfu/ml to 7.6X106 cfu/ml, 6.7X106 cfu/ml and 1.0X106 cfu/ml respectively. The temperature of cassava mash increased from 26°C to 30°C. The pH decreased from 6.80 to 4.22 while the total titratable acidity increased from 0.70% to 0.94%. Escherichia coli, P. mirabilis, S. typhimurium and S. aureus were inhibited by L. plantarum and L. mesenteroides while E. agglomerans and K. pneumoniae were resistant to L. plantarum and L. mesenteroides respectively. Aspergillus niger and G. candidum inhibited S. aureus but E. agglomerans, K. pneumoniae, P. mirabilis and S. typhimurium were not affected. Enterobacter agglomerans, E. coli, P. mirabilis and S. aureus were inhibited by A. fumigatus while K. pneumoniae and S. typhimurium were resistant. Conclusion: These results suggested that consumption of fufu and other fermented cassava tubers could enhance less susceptibility to diseases caused by the test bacteria and fufu may be recommended for people suffering from infections caused by these microorganisms.

The effect of Mash-1 gene overexpression on neural cell proliferation, differentiation and learning and memory ability in C57BL/6 adult male mice after brain trauma / 临床神经病学杂志

Objective To investigate the effects of Mash-1 gene overexpression on neural cell proliferation, differentiation and learning and memory ability in C57BL/6 adult male mice after brain trauma. Methods One hundred and sixty healthy adult male C57BL/6 mice were randomly divided into sham operation group, simple trauma group, negative control group and overexpression group. Gene transfection using recombinant adenovirus Ad5-mMash-1. Detection of Mash-1 mRNA level by RT-PCR at 1 d before TBI and 1 d, 3 d, 7 d, 14 d after traumatic brain injury (TBI). Western blotting was used to detect the expression of Mash-1 protein. The learning and memory ability was evaluated by means of water maze. The proliferation of nerve cells in dentate gyrus and cerebral cortex of hippocampus at 3 d and 7 d after TBI were detected by immunofluorescence. Results Compared with those in sham operation group, the relative expression of Mash-1 mRNA in simple trauma group and negative control group at 1 d, 3 d, 7 d, 14 d after TBI were significantly lower (P<0. 05-0. 01), and the relative expression of Mash-1 mRNA in overexpression group at 1 d, 3 d, 7 d, 14 d after TBI were significantly higher ( all P<0. 01 ). The relative expression of Mash-1 mRNA in overexpression group at 1 d , 3 d , 7 d , 1 4 d after TBI were significantly higher than those in simple trauma group and negative control group (all P<0. 05). Compared with those in sham operation group, expression of Mash-1 protein in simple trauma group at 1 d, 7 d, 14 d after TBI and negative control group and overexpression group at 1 d, 3 d, 7 d, 14 d after TBI (P<0. 05 -0. 01), expression of Mash-1 protein in simple trauma group at 3 d after TBI (P<0. 05). The expression of Mash-1 protein in overexpression group at 1 d, 3 d, 7 d, 14 d after TBI were significantly higher than those in simple trauma group and negative control group (all P<0. 05). Compared with those in sham operation group, the number of BrdU positive cells in simple trauma group at 3 d, 7 d after TBI and the number of DCX positive cells at 3 d after TBI were significantly decreased (P<0. 05-0. 01), and they were significantly increased in overexpression group (all P<0. 05). The number of BrdU positive cells at 3 d, 7 d after TBI and the number of DCX positive cells at 3 d after TBI in overexpression group were significantly increased than those in simple trauma group (all P<0. 05). There was no statistical difference of escape latency between simple trauma group, negative control group and overexpression group at 1 d, 3 d, 7 d, 14 d after TBI (all P>0. 05). Compared with those in sham operation group, escape latency in simple trauma group, negative control group and overexpression group at 1 d, 3 d, 7 d, 14 d after TBI were significantly increased (all P<0. 05). Conclusion Overexpression of Mash-1 gene increases neuronal proliferation and differentiation in dentate gyrus and cortex of adult C57BL/6 mice after traumatic brain injury, but it has no effect on learning and memory ability.

Effects of Transfection of Mash-1 Gene on Neural Differentiation of Embryonic Stem Cell in Spinal Cord Injury Mice / 中国康复理论与实践

Objective To investigate the effects of overexpression of Mash-1 gene on functional recovery and neural differentiation of embryonic stem cells in spinal cord injury mice. Methods CE3 cell line with overexpression of Mash-1 gene was generated with murine stem cell virus. Spinal cord injury model was established with forceps compression in 4-week-old KM mice. Normal saline (model group, n=12), CE3 cells with or without overexpression Mash-1 gene (CE3-Mash-1 and CE3 groups, n=12 respectively) were transplanted into the ar-eas of injury 3 days after injury. They were assessed with the Basso Mouse Scale (BMS) 1, 7, 14, 21, and 28 days after injury. 6 mice from each group were sacrificed 14 and 28 days after injury respectively. The spinal cord area remained were observed with HE stained, and the expression of Oct3/4, nestin,β-tubulin III and glial fibrillary acidic protein (GFAP) were detected with immunofluorescence in the injured spinal cord in the CE3 and CE3-Mash-1 groups. Results The score of BMS significantly improved in CE3 and CE3-Mash-1 groups com-pared with that of the model group (F>84.471, P49.990, P0.05). Conclusion Overexpression of Mash-1 gene promotes CE3 cells to differentiate into neurons in spinal cord injury mice, and improve the motor function recovery.

Compositional studies and biological activities of some mash bean (Vigna mungo (L) Hepper) cultivars commonly consumed in Pakistan

BACKGROUND: In recent years, the desire to adopt a healthy diet has drawn attention to legume seeds and food products derived from them. Mash bean is an important legume crop used in Pakistan however a systematic mapping of the chemical composition of mash bean seeds is lacking. Therefore seeds of four mash bean (Vigna mungo (L.) Hepper, family Leguminoseae) cultivars (NARC-Mash-1, NARC-Mash-2, NARC-Mash-3, NARC-Mash-97) commonly consumed in Pakistan have been analyzed for their chemical composition, antioxidant potential and biological activities like inhibition of formation of advanced glycation end products (AGE) activity and tyrosinase inhibition activity. RESULTS: The investigated cultivars varied in terms of biochemical composition to various extents. Mineral composition indicated potassium and zinc in highest and lowest amounts respectively, in all cultivars. The amino acid profile in protein of these cultivars suggested cysteine is present in lowest quantity in all cultivars while fatty acid distribution pattern indicated unsaturated fatty acids as major fatty acids in all cultivars. All cultivars were found to be rich source of tocopherols and sterols. Fourier transform infrared spectroscopy (FTIR) fingerprints of seed flour and extracts indicated major functional groups such as polysaccharides, lipids, amides, amines and amino acids. Results indicated that all investigated cultivars possessed appreciable antioxidant potential. CONCLUSIONS: All cultivars are rich source of protein and possess sufficient content of dietary fiber, a balanced amino acid profile, low saturated fatty acids and antioxidant capacity that rationalizes many traditional uses of seeds of this crop besides its nutritional importance. The collected data will be useful for academic and corporate researchers, nutritionists and clinical dieticians as well as consumers. If proper attention is paid, it may become an important export commodity and may fetch considerable foreign exchange for Pakistan.

Effect of Shouwu Yizhi Capsule on Gene Expression in Notch/Delta Signal Pathway of Vascular Dementia Model Rats / 中医杂志

Objective To investigate the effect and mechanism of Shouwu Yizhi Capsule (Capsule of Radix Polygoni Multiflori and Semen Coicis for dementia) on the Notch/Delta signal pathway in experimental rats with vascular dementia (VD). Methods The models were established with the modified Pulsinelli 4 vessel occlusion method. They were randomized into Shouwu Yizhi Capsule group,piracetam group,model group,and sham operation group with 14 rats in each group. Seven days after modeling,the Shouwu Yizhi Capsule group was administered intragastrically Shouwu Yizhi Capsule solution 0.08g/ml,the piracetam group was prescribed intragastrically piracetam solution 0.02g/ml,and the model and sham operation groups were given intragastrically normal saline. Twenty days later,the mRNA expression of HES1,Mash1,and ?-APP on Notch/Delta singal pathway was determined by real-time quantitative fluorescent PCR. Results Compared with the model and piracetam groups,the mRNA expression of HES1 the in Shouwu Yizhi Capsule group was significantly increased (P0.05). Conclusion Shouwu Yizhi Capsule could effectively activate the interaction of HES1,Mash1,and ?-APP on the Notch/Delta signal pathway,being the possible mechanism in the treatment of VD.