Abstract 14580: Methodological Challenges Conducting In Vitro Ischemia and Reperfusion: A Fundamental Problem in Cell Viability Determination

Circulation ◽  
2021 ◽  
Vol 144 (Suppl_2) ◽  
Author(s):  
Santiago J Miyara ◽  
Muhammad Shoaib ◽  
Yusuke Endo ◽  
Rishabh C Choudhary ◽  
Kei Hayashida ◽  
...  

Background: Oxygen & Glucose Deprivation (OGD) and Reperfusion (OGD-R) is considered one of the best models for studying ischemia and reperfusion injury (IRI) in vitro. Cell viability (CV) experimentation can aid in estimating cell survival after IRI insults and potential benefits from therapeutic attempts. However, the different metabolites used in various CV assays may compromise the usefulness and validity of various CV tools. We conducted two independent cell viability assays (WST-8 & ATP) after OGD and OGD-R on neurons (NE) and astrocytes (AS). Methods: NE (HT-22) and AS (C8-D1A) were subjected to 6h OGD only and 6h OGD followed by 20h Reperfusion (OGD-R). OGD is based on the combination of chemical ischemia (standard culture media depleted of glucose and other energy sources) and severe hypoxia (O2 ~1.4 to 1.8%) for 6h, while 20h reperfusion consists of readdition of standard culture media and conditions (21% O2, 5% CO2, 37°C). CV was determined by WST-8 and ATP “CellTiter-Glo 2.0” assays. Results: By WST-8 assay, OGD decreased CV in NE (Fig. 1A, P value = 0.0121), but increased CV in AS (Fig. 1A, P value = 0.0079). OGD-R decreased CV in NE and AS (Fig. 2A, P value = 0.0010, 0.0146, respectively). By ATP assay, OGD decreased CV in NE (Fig. 1B, P value <0.0001) and AS (Fig. 1C, P value <0.0001). OGD-R also decreased CV in NE (Fig. 2B, P value <0.0001) and AS (Fig. 2C, P value = 0.0001). Conclusions: The current data reveals opposite CV results after OGD in AS when comparing WST-8 and ATP assays; OGD caused CV decrease in NE but increased in AS, which constitutes a paradoxical response based on previous literature. However, OGD-R caused similar injury patterns in NE and AS from WST-8 and ATP assays. It is unknown why OGD increased CV in AS through WST-8 after OGD, however, it can potentially occur due to AS hypermetabolism leading to increased NADPH+ production, which is the main substrate in this CV estimation. We conclude that CV should be carefully assessed with multiple, independent CV assays.

2020 ◽  
Vol 17 (3) ◽  
pp. 259-266 ◽  
Author(s):  
Xuan Chen ◽  
Sumei Zhang ◽  
Peipei Shi ◽  
Yangli Su ◽  
Dong Zhang ◽  
...  

Objective: Ischemia-reperfusion (I/R) injury is a pathological feature of ischemic stroke. This study investigated the regulatory role of miR-485-5p in I/R injury. Methods: SH-SY5Y cells were induced with oxygen and glucose deprivation/reoxygenation (OGD/R) to mimic I/R injury in vitro. Cells were transfected with designated constructs (miR-485- 5p mimics, miR-485-5p inhibitor, lentiviral vectors overexpressing Rac1 or their corresponding controls). Cell viability was evaluated using the MTT assay. The concentrations of lactate dehydrogenase, malondialdehyde, and reactive oxygen species were detected to indicate the degree of oxidative stress. Flow cytometry and caspase-3 activity assay were used for apoptosis assessment. Dual-luciferase reporter assay was performed to confirm that Rac family small GTPase 1 (Rac1) was a downstream gene of miR-485-5p. Results: OGD/R resulted in decreased cell viability, elevated oxidative stress, increased apoptosis, and downregulated miR-485-5p expression in SH-SY5Y cells. MiR-485-5p upregulation alleviated I/R injury, evidenced by improved cell viability, decreased oxidative markers, and reduced apoptotic rate. OGD/R increased the levels of Rac1 and neurogenic locus notch homolog protein 2 (Notch2) signaling-related proteins in cells with normal miR-485-5p expression, whereas miR- 485-5p overexpression successfully suppressed OGD/R-induced upregulation of these proteins. Furthermore, the delivery of vectors overexpressing Rac1 in miR-485-5p mimics-transfected cells reversed the protective effect of miR-485-5p in cells with OGD/R-induced injury. Conclusion: This study showed that miR-485-5p protected cells following I/R injury via targeting Rac1/Notch2 signaling suggest that targeted upregulation of miR-485-5p might be a promising therapeutic option for the protection against I/R injury.


2011 ◽  
Vol 26 (S2) ◽  
pp. 908-908
Author(s):  
H.R. Sadeghnia ◽  
S.H. Mousavi ◽  
Z. Tayarani-Najaran ◽  
M. Asghari

The serum/glucose deprivation (SGD)-induced cell death in cultured PC12 cells represents a useful in vitro model for the study of brain ischemia and neurodegenerative disorders.Nigella sativa L. and its active component, thymoquinone (TQ) have been known as a source of antioxidants. In the present study, the protective effects of N. sativa and TQ on cell viability and reactive oxygen species (ROS) production in cultured PC12 cells were investigated under SGD conditions. PC12 Cells were pretreated with different concentrations of N. sativa extract (15.62–250 μg/ml) and TQ (1.17–150 μM) for 2 h and then subjected to SGD for 6 or 18 h. Cell viability was quantitated by MTT assay. Intracellular ROS production was measured by flow cytometry using 2’,7’-dichlorofluorescin diacetate (DCF-DA) as a probe. SGD induced significant cells toxicity after 6, 18, or 24 h (p < 0.001). Pretreatment with N. sativa (15.62–250 μg/ml) and TQ (1.17–37.5 μM) reduced SGD-induced cytotoxicity in PC12 cells after 6 and 18 h. A significant increase in intracellular ROS production was seen following SGD (p < 0.001). N. sativa (250 μg/ml, p < 0.01) and TQ (2.34, 4.68, 9.37 μM, p < 0.01) pretreatment reversed the increased ROS production following ischemic insult. The experimental results suggest that N. sativa extract and TQ protects the PC12 cells against SGD-induced cytotoxicity via antioxidant mechanisms. Our findings might raise the possibility of potential therapeutic application of N. sativa extract and TQ for managing cerebral ischemic and neurodegenerative disorders.


RSC Advances ◽  
2017 ◽  
Vol 7 (55) ◽  
pp. 34473-34481 ◽  
Author(s):  
Xiao-Hui Zheng ◽  
Chun-Ping Liu ◽  
Zeng-Guang Hao ◽  
Yan-Fang Wang ◽  
Xian-Li Li

Linalool causes attenuation of IR induced cell death and apoptosis eitherin vitroorin vivo.


2017 ◽  
Vol 2017 ◽  
pp. 1-18 ◽  
Author(s):  
Divya S. Varghese ◽  
Shama Parween ◽  
Mustafa T. Ardah ◽  
Bright Starling Emerald ◽  
Suraiya A. Ansari

Human embryonic stem cells (hESCs) are being used extensively in array of studies to understand different mechanisms such as early human embryogenesis, drug toxicity testing, disease modeling, and cell replacement therapy. The protocols for the directed differentiation of hESCs towards specific cell types often require long-term cell cultures. To avoid bacterial contamination, these protocols include addition of antibiotics such as pen-strep and gentamicin. Although aminoglycosides, streptomycin, and gentamicin have been shown to cause cytotoxicity in various animal models, the effect of these antibiotics on hESCs is not clear. In this study, we found that antibiotics, pen-strep, and gentamicin did not affect hESC cell viability or expression of pluripotency markers. However, during directed differentiation towards neural and hepatic fate, significant cell death was noted through the activation of caspase cascade. Also, the expression of neural progenitor markers Pax6, Emx2, Otx2, and Pou3f2 was significantly reduced suggesting that gentamicin may adversely affect early embryonic neurogenesis whereas no effect was seen on the expression of endoderm or hepatic markers during differentiation. Our results suggest that the use of antibiotics in cell culture media for the maintenance and differentiation of hESCs needs thorough investigation before use to avoid erroneous results.


1973 ◽  
Vol 138 (3) ◽  
pp. 574-592 ◽  
Author(s):  
J. D. Broome ◽  
M. W. Jeng

Numerous lines of mouse lymphoid tumors (13 of 22 tested) showed, with increased sensitivity, a property of normal mouse splenic lymphocytes, the potential for growth promotion in vitro by specific thiols added to standard culture media. For lymphoma L1210 (V), structure activity relationships were examined; 9 of 30 thiols promoted growth; the most active was α-thioglycerol, effective at 0.2 µM. Thiols became oxidized under conditions of tissue culture and had half-lives of less than 8 h. Disulfides of active thiols promoted growth of lymphoma cells. The mitogenic response of splenic lymphocytes to lectins was increased by thiols-disulfides which promoted the growth of lymphoma cells, but the response varied with the mitogen preparation used and under some conditions thiols-disulfides were inhibitory.


2021 ◽  
Vol 8 ◽  
Author(s):  
Jennifer L. MacNicol ◽  
Wendy Pearson

In vitro organ culture can provide insight into isolated mucosal responses to particular environmental stimuli. The objective of the present study was to investigate the impact of a prolonged culturing time as well as the addition of acidic gastric fluid into the in vitro environment of cultured gastric antral tissue to evaluate how altering the commonly used neutral environment impacted tissue. Furthermore, we aimed to investigate the impact of G's Formula, a dietary supplement for horses, on the secretion of gastrin, interleukin1-beta (IL-1β), and nitric oxide (NO). These biomarkers are of interest due to their effects on gastric motility and mucosal activity. Gastric mucosal tissue explants from porcine stomachs were cultured in the presence of a simulated gastric fluid (BL, n = 14), simulated gastric fluid containing the dietary supplement G's Formula (DF, n = 12), or an equal volume of phosphate buffered saline (CO, n = 14). At 48 and 60 h, 10−5 M carbachol was used to stimulate gastrin secretion. Cell viability was assessed at 72 h using calcein and ethidium-homodimer 1 staining. Media was analyzed for gastrin, IL-1β, and NO at 48, 60, and 72 h. There were no effects of treatment or carbachol stimulation on explant cell viability. Carbachol resulted in a significant increase in gastrin concentration in CO and DF treatments, but not in BL. NO was higher in CO than in BL, and NO increased in the CO and DF treatments but not in BL. In conclusion, the addition of carbachol and gastric digests to culture media did not impact cell viability. The use of an acidic gastric digest (BL) reduced the effect of cholinergic stimulation with carbachol at a concentration of 10−5 M and reduced NO secretion. The addition of the dietary supplement to the gastric digest (DF) appeared to mediate these effects within this model. Further research is required to evaluate the specific effects of this dietary supplement on direct markers of mucosal activity and the functional relevance of these results in vivo.


Materials ◽  
2020 ◽  
Vol 13 (8) ◽  
pp. 1843 ◽  
Author(s):  
Anna Iliadi ◽  
Despina Koletsi ◽  
Spyridon N. Papageorgiou ◽  
Theodore Eliades

Use of thermoplastic material in orthodontics, either as aligner or as retainer appliances, is common practice and is likely to increase in the years to come. However, no systematic assessment on safety considerations of these adjuncts has been implemented up to date. The aim of this systematic review was to collectively appraise the existing evidence from both clinical and laboratory studies, on whether these appliances are associated with any estrogenic/cytotoxic effects or bisphenol-A (BPA) and monomer leaching. Eight electronic databases were searched with no limits in December 22, 2019, for published and unpublished research. Eligibility criteria comprised of studies of any design, describing use of any type of thermoplastic aligner. Study selection, data extraction and risk of bias (RoB) assessment was done independently, either in duplicate or confirmed by a second reviewer. Random effects meta-analyses of weighted mean differences (WMD) with associated 95% Confidence Intervals (CIs) were planned. Quality of the evidence was evaluated with Grading of Recommendations Assessment, Development and Evaluation (GRADE). A total of 58 articles were initially identified, while 5 were included in qualitative synthesis and 2 of those contributed to the quantitative syntheses. Four studies were in-vitro, while one was a randomized controlled trial; all assessed some type of orthodontic aligner or retainer, either as-received or retrieved. Risk of bias recordings ranged between unclear and high for all studies. Proliferation induction capacity of thermoplastic appliances’ eluents on MCF-7 cells failed to be confirmed compared to beta-estradiol (2 studies: 5% v/v, WMD: −182.08; 95% CI: −198.83, −165.33; p-value < 0.001; and 20% v/v, WMD: −184.53; 95% CI: −206.17, −162.88; p-value < 0.001). No cytotoxic activity was detected as well. In addition, although evidence from in-vitro studies was indicative of no traceable detection of BPA or other monomers, the findings from a single clinical trial were allied to increased levels of BPA in whole stimulated saliva, after up to 30 days of thermoplastic retainer usage, compared to standard Hawley retainer. The quality of the evidence overall was low to medium. Current data from in-vitro research are indicative of an absence of an estrogenic or cytotoxic effect of thermoplastic aligners or retainers. Regarding BPA or monomer release, evidence from clinical and laboratory studies appear inconsistent.


2006 ◽  
Vol 96 (4) ◽  
pp. 1101-1110 ◽  
Author(s):  
Ruiqin Liu ◽  
Asuka Suzuki ◽  
Zhiwei Guo ◽  
Yoshikuni Mizuno ◽  
Takao Urabe

1989 ◽  
Vol 1 (3) ◽  
pp. 231 ◽  
Author(s):  
BD Bavister ◽  
M Golden

In vivo fertilized hamster one-cell eggs (embryos) were cultured in a simple medium that was modified to provide a wide range of concentrations and ratios of the four major cation components (sodium, potassium, calcium and magnesium) while maintaining total osmotic pressure at 290 +/- 5 mosm. Embryos were cultured in these media to find the optimum cation concentrations for supporting the first cleavage division in vitro and to determine if physiologically abnormal cation concentrations and/or ratios in standard culture media could account for the 'two-cell block' to development in vitro in this species. Despite using a broad range of ratios for sodium:potassium (from 45:1 to 5:1) and for calcium:magnesium (from 17:1 to 1:1), there were no significant differences in the proportions of fertilized eggs that underwent the first cleavage division (approx. 60-80% across all treatments), and none of the two-cell embryos underwent further cleavage during extended culture. These data demonstrate that the first cleavage division of hamster embryos in vitro is insensitive to extracellular concentrations and ratios of the major cations, and that the non-physiological concentrations and/or ratios of these cations in the culture medium are not the primary reason for the failure of hamster zygotes to develop past the two-cell stage in vitro.


Pharmaceutics ◽  
2022 ◽  
Vol 14 (1) ◽  
pp. 104
Author(s):  
Margarida Ferreira-Silva ◽  
Catarina Faria-Silva ◽  
Manuela C. Carvalheiro ◽  
Sandra Simões ◽  
Helena Susana Marinho ◽  
...  

Ischemia and reperfusion injury (IRI) is a common complication caused by inflammation and oxidative stress resulting from liver surgery. Current therapeutic strategies do not present the desirable efficacy, and severe side effects can occur. To overcome these drawbacks, new therapeutic alternatives are necessary. Drug delivery nanosystems have been explored due to their capacity to improve the therapeutic index of conventional drugs. Within nanocarriers, liposomes are one of the most successful, with several formulations currently in the market. As improved therapeutic outcomes have been demonstrated by using liposomes as drug carriers, this nanosystem was used to deliver quercetin, a flavonoid with anti-inflammatory and antioxidant properties, in hepatic IRI treatment. In the present work, a stable quercetin liposomal formulation was developed and characterized. Additionally, an in vitro model of ischemia and reperfusion was developed with a hypoxia chamber, where the anti-inflammatory potential of liposomal quercetin was evaluated, revealing the downregulation of pro-inflammatory markers. The anti-inflammatory effect of quercetin liposomes was also assessed in vivo in a rat model of hepatic IRI, in which a decrease in inflammation markers and enhanced recovery were observed. These results demonstrate that quercetin liposomes may provide a significant tool for addressing the current bottlenecks in hepatic IRI treatment.


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