scholarly journals Expression of Otx Genes in Müller Cells Using an In Vitro Experimental Model of Retinal Hypoxia

2021 ◽  
Vol 2021 ◽  
pp. 1-10
Author(s):  
Claudio Azzolini ◽  
Simone Donati ◽  
Giovanni Micheloni ◽  
Vittoria Moretti ◽  
Roberto Valli ◽  
...  

Introduction. Müller glial cells typically activate to react to hypoxic tissue damage in several retinal diseases. We evaluated the in vitro response to a hypoxia-mimicking stimulus on the expression of a set of genes, known to contribute to eye morphogenesis and cell differentiation. Materials and Methods. A MIO-M1 Müller cell line was cultured in a hypoxia-mimicking environment by the addition of cobalt chloride to the culture medium, followed by a recovery time in which we mimic restoration from the hypoxic insult. The HIF-1α protein and VEGF-A gene expression were quantified to verify the induction of a hypoxia-like state. Results. Among the genes under study, we did not observe any difference in the expression levels of Otx1 and Otx2 during treatment; conversely, Otx1 was overexpressed during recovery steps. The VEGF-A gene was strongly upregulated at both the CoCl2 and recovery time points. The transactivated isoform (TA) of the TP73 gene showed an overexpression in long-term exposure to the hypoxic stimulus with a further increase after recovery. Discussion. Our molecular analysis is able to describe the activation of a set of genes, never before described, that can drive the response to a hypoxia-like status. The improved comprehension of these cellular events will be useful for designing new therapeutical approaches for retinal pathologies.

Biology Open ◽  
2021 ◽  
Vol 10 (11) ◽  
Author(s):  
Ekaterina V. Borvinskaya ◽  
Albina A. Kochneva ◽  
Polina B. Drozdova ◽  
Olga V. Balan ◽  
Victor G. Zgoda

ABSTRACT The protein composition of the cestode Schistocephalus solidus was measured in an experiment simulating the trophic transmission of the parasite from a cold-blooded to a warm-blooded host. The first hour of host colonisation was studied in a model experiment, in which sticklebacks Gasterosteus aculeatus infected with S. solidus were heated at 40°C for 1 h. As a result, a decrease in the content of one tegument protein was detected in the plerocercoids of S. solidus. Sexual maturation of the parasites was initiated in an experiment where S. solidus larvae were taken from fish and cultured in vitro at 40°C for 48 h. Temperature-independent changes in the parasite proteome were investigated by incubating plerocercoids at 22°C for 48 h in culture medium. Analysis of the proteome allowed us to distinguish the temperature-induced genes of S. solidus, as well as to specify the molecular markers of the plerocercoid and adult worms. The main conclusion of the study is that the key enzymes of long-term metabolic changes (glycogen consumption, protein production, etc.) in parasites during colonisation of a warm-blooded host are induced by temperature.


2015 ◽  
Vol 2015 ◽  
pp. 1-11 ◽  
Author(s):  
Richard Rosen ◽  
Tommaso Vagaggini ◽  
Yueqin Chen ◽  
Dan-Ning Hu

Hypoxia is the most important stimulus leading to upregulation of VEGF in the retina and this is caused by accumulation of hypoxia-inducible factors-1α(HIF-1α) protein. The effects of zeaxanthin, a natural phytochemical, on the VEGF and HIF-1αexpression in the primary culture of human retinal pigment epithelial (RPE) cells were studied. An in vitro RPE cell hypoxia model was established by placing cells under 1% oxygen pressure or by adding cobalt chloride (CoCl2) to the culture medium. RPE cells and conditioned media were collected from cultures treated with and without zeaxanthin under normoxic and hypoxic conditions. VEGF and HIF-1αprotein and RNA levels were measured by ELISA kits and RT-PCR, respectively. Hypoxia caused a significant increase of VEGF expression and accumulation of HIF-1αin RPE cells. Zeaxanthin at 50–150 μM significantly inhibited the expression of VEGF and accumulation of HIF-1αprotein caused by hypoxia but did not affect expression of VEGF and HIF-1αunder normoxic conditions. This is the first report on the effect of zeaxanthin on VEGF and HIF-1αlevels in cultured RPE cells and suggests that zeaxanthin may have potential value in the prevention and treatment of various retinal diseases associated with vascular leakage and neovascularization.


HortScience ◽  
1995 ◽  
Vol 30 (4) ◽  
pp. 873G-874
Author(s):  
D. Sankhla ◽  
T.D. Davis ◽  
N. Sankhla ◽  
A. Upadhyaya

This report describes an efficient in vitro regeneration protocol for H. patens (firebush), a heat-tolerant ornamental shrub native to tropical and subtropical America. Shoot cultures were initially established using shoot tips placed on MS-revised medium containing 2.3 μM 2,4-D, 2.3 μM kinetin, and 0.25% polyvinylpyrrolidone. Other types of explants (nodal and internodal segments, leaf pieces, floral buds) did not regenerate shoots when placed on this medium. Two-month-old plantlets derived from the shoot tips were subcultured on MS medium supplemented with 0.5 μM thidiazuron (TDZ), and within 3 to 4 weeks, some callus was produced at the root–shoot junction. When this callus, with a small portion of the root and shoots, was placed on MS medium with 0.05 μM TDZ and 0.01 μM ABA, prolific shoot formation occurred within 3 to 4 weeks followed by root formation. By regular subculturing every 5 to 6 weeks, hundreds of plantlets have been obtained over the past 3 years with no apparent decline in regeneration potential. Addition of activated charcoal (0.5%) to the culture medium has greatly improved growth of the plantlets.


2016 ◽  
Vol 8 (4) ◽  
pp. 511-519 ◽  
Author(s):  
Mihaela A. CIOLOCA ◽  
Andreea M. TICAN ◽  
Maria IANOŞI ◽  
Carmen L. BĂDĂRĂU

The current paper aimed to study the in vitro response of potato genotypes to water stress induced by adding sorbitol and polyethylene glycol in the culture medium. The biological material analysed in the experiment was represented by a Romanian line ‘LP 11-1525/1’ and two isogenic lines ‘LI 101’ and ‘LI 102’. For cultures initiation, the line ‘LP 11-1525/1’ was started from meristems and for the other two genotypes true potato seeds were used. The studied potato genotypes behaved differently depending on the analysed parameters and on the treatment applied for drought tolerance. It was noted that the line ‘LP 11-1525/1’ achieved good results for most of the growth parameters studied, and also the lines derived from true potato seeds behaved well, in some cases even exceeding the line derived from meristems. Of the lines derived from true potato seeds, the best performance was noted for line ‘LI 101-6’ in all the analysed parameters, both on sorbitol and PEG medium. In addition, lines ‘LI 101-7’ and ‘LI 102-4’ achieved good results on both variants of medium used to mediate water stress. Therefore, establishing drought tolerance individuals within populations derived from true potato seeds using sorbitol and polyethylene glycol might be applied.


2018 ◽  
Vol 39 (5) ◽  
pp. 2001
Author(s):  
Vanúzia Gonçalves Menezes ◽  
Ricássio De Sousa Barberino ◽  
Bruna Bortoloni Gouveia ◽  
Rodrigo José de Souza Gonçalves ◽  
Jackson Roberto Guedes da Silva Almeida ◽  
...  

This study evaluated the effect of Amburana cearensis extract as a preservation or culture medium for ovine ovarian tissue. Ovarian fragments were fixed in 4% buffered formaldehyde for 18 h (fresh control), stored in Minimal Essential Medium (MEM) or in A. cearensis extract (0.1; 0.2 or 0.4 mg/mL) at a temperature of 4ºC for 6, 12 or 24 h (preservation - experiment 1) or cultured for 7 days in ?-MEM+ or in A. cearensis extract without (0.1; 0.2 or 0.4 mg/mL) or with supplements (0.1+ ; 0.2+ or 0.4+ mg/ mL; experiment 2). The percentages of morphologically normal follicles and follicular activation were submitted to analysis of variance (ANOVA) and Tukey´s test. The values of TUNEL-positive cells were submitted to Chi-square test (P < 0.05). The storage of fragments for 6 h in MEM showed higher percentages of normal follicles (62%) and a lower rate of TUNEL positive cells (36.17%) compared to other treatments (normal follicles: 46%; 43% and 52%; TUNEL positive cells: 58.57%; 55.30% and 55.63% for Amb 0.1; Amb 0.2 and Amb 0.4 mg/mL, respectively). However, after 12 or 24 h, MEM (12 h: 48%; 24 h: 45%) and Amb 0.2 mg/mL (12 h: 37%; 24 h: 39%) showed similar percentages of normal follicles and TUNEL positive cells (MEM - 12 h: 43.26%; 24 h: 58%; Amb 0.2 mg/mL - 12 h: 50%; 24 h: 61%). After culture, ?-MEM+ recorded a higher percentage of normal follicles (58.25%) than A. cearensis treatments (32.8%; 25.4% and 34.2% for Amb 0.1; Amb 0.2 and Amb 0.4 mg/mL, and 22.25%; 20.0% and 36.6% for Amb 0.1+ ; Amb 0.2+ and Amb 0.4+ mg/mL, respectively) (P < 0.05). Follicular activation increased in all treatments (52.5%; 36.73%; 54.05%; 47.5% and 58.19% for ?-MEM+ ; Amb 0.1; Amb 0.1+ ; Amb 0.2+ and Amb 0.4+ mg/mL, respectively) compared to the fresh control (11.65%), except for Amb 0.2 mg/mL (23.69%) and Amb 0.4 mg/mL (28.85%) (P > 0.05). Moreover, after in vitro culture, A. cearensis at a concentration of 0.1 mg/mL maintained the percentage of TUNEL positive cells (30.0%) in a way that is similar to that observed in the fresh control (22%) (P > 0.05). In conclusion, ovine preantral follicles can be preserved at 4°C in MEM for 6 h. For longer periods of preservation (24 h), MEM and 0.2 mg/mL A. cearensis are recommended. Moreover, after in vitro culture, A. cearensis extract (0.1 mg/mL) showed higher activation and lower DNA fragmentation in ovine preantral follicles.


Toxics ◽  
2020 ◽  
Vol 8 (1) ◽  
pp. 9 ◽  
Author(s):  
Zoi Zagoriti ◽  
Mohamed A. El Mubarak ◽  
Konstantinos Farsalinos ◽  
Stavros Topouzis

Cigarette smoking (CS) causes significant morbidity worldwide, attributed to the numerous toxicants generated by tobacco combustion. Electronic cigarettes (ECIG) and heated tobacco products (HTP) are considered alternative smoking/vaping products that deliver nicotine through an inhaled aerosol and emit fewer harmful constituents than CS. However, their long-term impacts on human health are not well established. Nicotine exposure has been linked to lipolysis and body weight loss, while smoking has been associated with insulin resistance and hyperinsulinemia. Enhanced function of beige (thermogenic) adipocytes has been proposed as a means to reduce obesity and metabolic disorders. In this study, we compared the effect of extract-enriched media via exposure of culture medium to CS, HTP aerosol, and ECIG aerosol on the viability and the differentiation of 3T3-L1 pre-adipocytes to beige adipocytes. Only CS extract caused a decrease in cell viability in a dose- and time-dependent manner. Furthermore, relative lipid accumulation and expression levels of the adipocyte markers Pgc-1α, Ppar-γ and Resistin were significantly decreased in cells exposed to CS extract. Our results demonstrate that CS extract, in contrast to HTP and ECIG extracts, significantly impairs differentiation of pre-adipocytes to beige adipocytes and may therefore impact significantly adipose tissue metabolic function.


2001 ◽  
Vol 281 (4) ◽  
pp. L1021-L1027 ◽  
Author(s):  
Corrie B. Allen ◽  
B. Kelly Schneider ◽  
Carl W. White

Exposure of cultured cells to changing gaseous environments is used as a model for understanding both the immediate and long-term effects of such exposures on lung cells in vivo. We conducted experiments with polystyrene tissue culture flasks and plates to determine the time course of changes in oxygen concentration occurring under in vitro conditions. Only a few minutes were required for the concentration of oxygen in the environmental chamber to reach equilibrium with that of the flushing gas. However, >3 h were required for the oxygen content in the medium in the tissue culture flasks and plates to achieve equilibrium. The low solubility of oxygen in aqueous solutions and the limited diffusion of oxygen through a boundary layer of gas above the medium are the major barriers to rapid oxygen transport into the culture medium. The delay in achieving the desired Po 2 within the culture medium limits the temporal precision of any assessment of the correlation of cellular events with the concentration of oxygen to which those cells are exposed.


1983 ◽  
Vol 104 (4) ◽  
pp. 495-501 ◽  
Author(s):  
Tetsuro Okabe ◽  
Hiroshi Hidaka ◽  
Nakaaki Ohsawa ◽  
Toshio Tsushima

Abstract. In an attempt to obtain an in vitro experimental model for aldosteronoma, primary culture was initiated with adenomas from 3 patients with primary aldosteronism. The cells grown in culture retained the morphology and functional properties characteristic of aldosteronoma cells well for periods of up to 200 days. The cells formed monolayer cell colonies and showed an epithelioid morphology with small nuclei containing prominent nucleoli. The cells possessed a clear, eosinophilic cytoplasm resembling that of aldosteronoma cells in vivo. The cultured cells continued to secrete large amounts of aldosterone throughout the culture period. The cells responded to angiotensin II and III by increased release of aldosterone into the culture medium. They also responded to Db-cAMP and ACTH by increased secretion of the hormone.


2010 ◽  
Vol 56 (12) ◽  
pp. 987-995 ◽  
Author(s):  
Jesús Serrano-Luna ◽  
Manuel Gutiérrez-Meza ◽  
Ricardo Mejía-Zepeda ◽  
Silvia Galindo-Gómez ◽  
Víctor Tsutsumi ◽  
...  

Trophozoites of Entamoeba histolytica HM-1:IMSS become less virulent after long-term maintenance in axenic cultures. The factors responsible for the loss of virulence during in vitro cultivation remain unclear. However, it is known that in vitro cultivation of amoeba in culture medium supplemented with cholesterol restores their virulence. In this study, we analyzed the effect of adding phosphatidylcholine–cholesterol (PC–Chol) liposomes to the culture medium and evaluated the effect of this lipid on various biochemical and biological functions of E. histolytica HM-1:IMSS in terms of its virulence. The addition of PC–Chol liposomes to the culture medium maintained the virulence of these parasites against hamster liver at the same level as the original virulent E. histolytica strain, even though these amoebae were maintained without passage through hamster liver for 18 months. The trophozoites also showed increased endocytosis, erythrophagocytosis, and carbohydrate residue expression on the amoebic surface. Protease activities were also modified by the presence of cholesterol in the culture medium. These findings indicate the capacity of cholesterol to preserve amoeba virulence and provide an alternative method for the maintenance of virulent E. histolytica trophozoites without the need for in vivo procedures.


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