Neural stem cell properties of Müller glia in the mammalian retina: regulation by Notch and Wnt signaling

The retina in adult mammals, unlike those in lower vertebrates such as fish and amphibians, is not known to support neurogenesis. However, when injured, the adult mammalian retina displays neurogenic changes, raising the possibility that neurogenic potential may be evolutionarily conserved and could be exploited for regenerative therapy. Here, we show that Müller cells, when retrospectively enriched from the normal retina, like their radial glial counterparts in the central nervous system (CNS), display cardinal features of neural stem cells (NSCs), i.e., they self-renew and generate all three basic cell types of the CNS. In addition, they possess the potential to generate retinal neurons, both in vitro and in vivo. We also provide direct evidence, by transplanting prospectively enriched injury-activated Müller cells into normal eye, that Müller cells have neurogenic potential and can generate retinal neurons, confirming a hypothesis, first proposed in lower vertebrates. This potential is likely due to the NSC nature of Müller cells that remains dormant under the constraint of non-neurogenic environment of the adult normal retina. Additionally, we demonstrate that the mechanism of activating the dormant stem cell properties in Müller cells involves Wnt and Notch pathways. Together, these results identify Müller cells as latent NSCs in the mammalian retina and hence, may serve as a potential target for cellular manipulation for treating retinal degeneration.     

Effects of high-fat diet and age on the blood lipidome and circulating endocannabinoids of female C57BL/6 mice

Alterations in lipid metabolism play a significant role in the pathogenesis of obesity-associated disorders, and dysregulation of the lipidome across multiple diseases has prompted research to identify novel lipids indicative of disease progression. To address the significant gap in knowledge regarding the effect of age and diet on the blood lipidome, we used shotgun lipidomics with electrospray ionization-mass spectrometry (ESI-MS). We analyzed blood lipid profiles of female C57BL/6 mice following high-fat diet (HFD) and low-fat diet (LFD) consumption for short (6 weeks), long (22 weeks), and prolonged (36 weeks) periods. We examined endocannabinoid levels, plasma esterase activity, liver homeostasis, and indices of glucose tolerance and insulin sensitivity to compare lipid alterations with metabolic dysregulation. Multivariate analysis indicated differences in dietary blood lipid profiles with the most notable differences after 6 weeks along with robust alterations due to age. HFD altered phospholipids, fatty acyls, and glycerolipids. Endocannabinoid levels were affected in an age-dependent manner, while HFD increased plasma esterase activity at all time points, with the most pronounced effect at 6 weeks. HFD-consumption also altered liver mRNA levels of PPARα, PPARγ, and CD36. These findings indicate an interaction between dietary fat consumption and aging with widespread effects on the lipidome, which may provide a basis for identification of female-specific obesity- and age-related lipid biomarkers.     

In vitro regeneration from bulb explants of Indian squill,Urginea indica Kunth

Callus cultures were established from bulb explants of diploid Urginea indica Kunth (Indian squill) on a modified basal medium of Murashige and Skoog (1962) supplemented with either 2 mg/l^-1 2,4-D+15% (v/v) CM or 4 mg/l^-1 2,4-D+2 mg/l^-1 NAA+2 mg/l^-1 KN+1 g/l^-1 YE. Shoot primordia developed after 2–3 subcultures in that medium. Increased growth of shoot primordia was obtained in media containing less auxins and vitamins. Rooted bulbous plantlets obtained were maintained in MS medium with 0.5% sucrose.Adventitious shoots were induced from adaxial epidermal cells of outer scales of regenerated bulbs used as secondary expiants in presence of 1 mg/l^-1 of 2,4-D with slightly higher concentration of the three vitamins of MS medium. From each scale leaf, approximately 400 bulblets were produced in 18 weeks in liquid culture. 90% of the plants transferred to potted soil have survived.     

The nutritional and metabolic indices in rats fed cholesterol-containing diets supplemented with durian at different stages of ripening

The aim of this investigation was to assess the nutritional and health properties of Mon Thong durian cultivar at different stages of ripening. The assessment was carried out in vitro and in vivo. The contents of dietary fibers, minerals and trace metals at different stages of ripening were comparable. Total polyphenols (mgGAE/100 g FW) and flavonoids (mg CE/100 gFW) in ripe durian (358.8 +/- 31.4 and 95.4 +/- 9.3) were significantly higher (p < 0.05) than in mature (216.1 +/- 1 and 39.9 +/- 3.8) and overripe (283.3 +/- 26.2 and 53.5 +/- 4.9). Antioxidant capacity (muMTE/100 g FW) in total polyphenol extracts of ripe durian measured by 1,1-diphenyl-2-picrylhydrazyl radical (DPPH) and [2,2'-azinobis (3-ethylbenzothiazoline-6-sulfonic acid)] (ABTS) assays (259.4 +/- 23.6 and 2341.8 +/- 93.2) were significantly higher (p < 0.05) than that of mature (151.6 +/- 15.2 and 1394.6 +/- 41.5) and overripe (201.7 +/- 19.4 and 1812.2 +/- 61.4) samples. The correlation coefficients between the bioactive compounds in different stages of ripening and their antioxidant capacities were high (R;{2} = 0.99). Then 35 male Wistar rats were divided into 5 dietary groups each of 7 and named Control, Chol, Chol/Mature, Chol/Ripe and Chol/Overripe. During 30 days of the experiment the rats of all 5 groups were fed basal diet (BD), which included wheat starch, casein, soybean oil, vitamin and mineral mixtures. The rats of the Control group were fed a BD only. To the BD of the Chol group was added 1% of cholesterol. The BD of the Chol/Mature, Chol/Ripe and Chol/Overripe groups was supplemented with 1% of cholesterol and 5% of the mature, ripe and overripe durian as freeze-dried powder, respectively. Diets containing ripe and to a lesser degree mature and overripe durian significantly hindered the rise in plasma lipids and also hindered a decrease in plasma antioxidant activity. The nitrogen retention in rats of the Chol/Ripe group was significantly higher (63.6%, P < 0.05) than in other diet groups and the level of the plasma glucose remained normal. A decrease in fibrinogen fraction with ripe durian included in rat's diets was shown by electrophoretic separation. These changes were detected mostly in the low molecular weight proteins of rat's serum. Histological examination of aorta showed only slight differences in the tissue. In conclusion, ripe durian contains higher quantity of bioactive compounds, has higher antioxidant capacity and nutritional value. It positively affects the plasma lipid profile, the plasma glucose and the antioxidant activity in rats fed cholesterol enriched diets. Therefore, the ripe durian supplemented diet could be beneficial for patient suffering from hypercholesterolemia and diabetes mellitus. <     

Regeneration and rapid multiplication of Bowiea volubilis Harv. in tissue culture

Callus cultures were raised from segments of inflorescence axis of Bowies volubilis Harv. (Liliaceae) on a modified basal medium of Murashige and Skoog (1962) (MS) supplemented with 1 mg 1^–1 2,4-dichlorophenoxy acetic acid (2,4-D) + 15% v/v coconut milk. Shoot primordia developed after 2–3 subcultures when auxin concentration was lowered. Rooted bulbous plants were obtained in MS medium without any hormone.Shoots were induced directly on scales of regenerated bulbs used as secondary explants on modified MS medium supplemented with 2 mg 1^–1 6-benzylaminopurine (BAP) + 0.05 mg 1^–1 2,4-D. These shoots grew and multiplied rapidly in shake culture using liquid MS medium. From each scale, 400–600 bulblets could be produced in 16–20 weeks period. Eighty percent of plants have survived on transferring to potted soil.     

An analysis of somatic and meiotic behaviour of chromosomes ofBowiea volubilis HARV.

A critical analysis of karyotype and meiosis ofBowiea volubilis Harv. showed normal bivalent formation with considerable irregularities in meiosis. Asynchrony is manifested to a significant extent within the anther where the range is between pollen grains and early stages of pollen mother cells.     

Optimization of an acoustic cell filter with a novel air-backflush system

Increasing worldwide demand for mammalian cell production capacity will likely be partially satisfied by a greater use of higher volumetric productivity perfusion processes. An important additional component of any perfusion system is the cell retention device that can be based on filtration, sedimentation, and/or acoustic technologies. A common concern with these systems is that pumping and transient exposure to suboptimal medium conditions may damage the cells or influence the product quality. A novel air-backflush mode of operating an acoustic cell separator was developed in which an injection of bioreactor air downstream of the separator periodically returned the captured cells to the reactor, allowing separation to resume within 20 s. This mode of operation eliminated the need to pump the cells and allows the selection of a residence time in the separator depending on the sensitivity of the cell line. The air-backflush mode of operating a 10L acoustic separator was systematically tested at 10(7) cells/mL to define reliable ranges of operation. Consistent separation performance was obtained for wide ranges of cooling airflow rates from 0 to 15 L/min and for backflush frequencies between 10 and 40 h(-1). The separator performance was optimized at a perfusion rate of 10 L/day to obtain a maximum separation efficiency of 92 +/- 0.3%. This was achieved by increasing the power setting to 8 W and using duty cycle stop and run times of 4.5 and 45 s, respectively. Acoustic cell separation with air backflush was successfully applied over a 110 day CHO cell perfusion culture at 10(7) cells/mL and 95% viability.