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Protection by the NO-Donor SNAP and BNP against Hypoxia/Reoxygenation in Rat Engineered Heart Tissue.

Görbe A, Eder A, Varga ZV, Pálóczi J, Hansen A, Ferdinandy P, Eschenhagen T - PLoS ONE (2015)

Bottom Line: H/R was accompanied by a small increase in LDH and non-significant increase in cTnI.SNAP and BNP showed small but significant protective effects during reoxygenation.The sensitivity of the model needs improvement.

View Article: PubMed Central - PubMed

Affiliation: Cardiovascular Research Group, Department of Biochemistry, University of Szeged, Szeged, Hungary; Pharmahungary Group, Szeged, Hungary.

ABSTRACT
In vitro assays could replace animal experiments in drug screening and disease modeling, but have shortcomings in terms of functional readout. Force-generating engineered heart tissues (EHT) provide simple automated measurements of contractile function. Here we evaluated the response of EHTs to hypoxia/reoxygenation (H/R) and the effect of known cardiocytoprotective molecules. EHTs from neonatal rat heart cells were incubated for 24 h in EHT medium. Then they were subjected to 180 min hypoxia (93% N2, 7% CO2) and 120 min reoxygenation (40% O2, 53% N2, 7% CO2), change of medium and additional follow-up of 48 h. Time-matched controls (40% O2, 53% N2, 7% CO2) were run for comparison. The following conditions were applied during H/R: fresh EHT medium (positive control), the NO-donor S-nitroso-N-acetyl-D,L-penicillamine (SNAP, 10(-7), 10(-6), 10(-5) M) or the guanylate cyclase activator brain type natriuretic peptide (BNP, 10(-9), 10(-8), 10(-7) M). Frequency and force of contraction were repeatedly monitored over the entire experiment, pH, troponin I (cTnI), lactate dehydrogenase (LDH) and glucose concentrations measured in EHT medium. Beating activity of EHTs in 24 h-medium ceased during hypoxia, partially recovered during reoxygenation and reached time-control values during follow-up. H/R was accompanied by a small increase in LDH and non-significant increase in cTnI. In fresh medium, some EHTs continued beating during hypoxia and all EHTs recovered faster during reoxygenation. SNAP and BNP showed small but significant protective effects during reoxygenation. EHTs are applicable to test potential cardioprotective compounds in vitro, monitoring functional and biochemical endpoints, which otherwise could be only measured by using in vivo or ex vivo heart preparations. The sensitivity of the model needs improvement.

No MeSH data available.


Related in: MedlinePlus

Comparison of EHT contractile behavior in 24 h medium control (24 h MC) and BNP treated groups (n = 6).(A) Beating pattern of EHTs. Grey boxes indicate beating periods of EHTs whereas black boxes show non-beating phases. (B) Total number of beats is expressed as the percentage of baseline. (C) Rate force product of EHTs during reoxygenation. (D) Histological parameters of EHT sections are visible. (E) cTnI and LDH release. (F) Glucose consumption. Data are expressed as mean ± SEM; **p<0.001 one-way ANOVA, followed by Dunett’s post hoc test, n = 6.
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pone.0132186.g005: Comparison of EHT contractile behavior in 24 h medium control (24 h MC) and BNP treated groups (n = 6).(A) Beating pattern of EHTs. Grey boxes indicate beating periods of EHTs whereas black boxes show non-beating phases. (B) Total number of beats is expressed as the percentage of baseline. (C) Rate force product of EHTs during reoxygenation. (D) Histological parameters of EHT sections are visible. (E) cTnI and LDH release. (F) Glucose consumption. Data are expressed as mean ± SEM; **p<0.001 one-way ANOVA, followed by Dunett’s post hoc test, n = 6.

Mentions: BNP did not affect the percentage of beating EHTs (Fig 5A). The sum of all beats (Fig 5B) and the rate-force product (Fig 5C) were all slightly higher than in the 24 h MC group with a maximal effect at BNP 10−8 M. The BNP (10−9 M, 10−8 M) treated group showed a significant increase the N:C ratio and nuclear circularity compared to 24 h MC (Fig 5D and S1 Fig). Biochemical markers and pH values did not differ among the groups (Fig 5E and 5F).


Protection by the NO-Donor SNAP and BNP against Hypoxia/Reoxygenation in Rat Engineered Heart Tissue.

Görbe A, Eder A, Varga ZV, Pálóczi J, Hansen A, Ferdinandy P, Eschenhagen T - PLoS ONE (2015)

Comparison of EHT contractile behavior in 24 h medium control (24 h MC) and BNP treated groups (n = 6).(A) Beating pattern of EHTs. Grey boxes indicate beating periods of EHTs whereas black boxes show non-beating phases. (B) Total number of beats is expressed as the percentage of baseline. (C) Rate force product of EHTs during reoxygenation. (D) Histological parameters of EHT sections are visible. (E) cTnI and LDH release. (F) Glucose consumption. Data are expressed as mean ± SEM; **p<0.001 one-way ANOVA, followed by Dunett’s post hoc test, n = 6.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4492769&req=5

pone.0132186.g005: Comparison of EHT contractile behavior in 24 h medium control (24 h MC) and BNP treated groups (n = 6).(A) Beating pattern of EHTs. Grey boxes indicate beating periods of EHTs whereas black boxes show non-beating phases. (B) Total number of beats is expressed as the percentage of baseline. (C) Rate force product of EHTs during reoxygenation. (D) Histological parameters of EHT sections are visible. (E) cTnI and LDH release. (F) Glucose consumption. Data are expressed as mean ± SEM; **p<0.001 one-way ANOVA, followed by Dunett’s post hoc test, n = 6.
Mentions: BNP did not affect the percentage of beating EHTs (Fig 5A). The sum of all beats (Fig 5B) and the rate-force product (Fig 5C) were all slightly higher than in the 24 h MC group with a maximal effect at BNP 10−8 M. The BNP (10−9 M, 10−8 M) treated group showed a significant increase the N:C ratio and nuclear circularity compared to 24 h MC (Fig 5D and S1 Fig). Biochemical markers and pH values did not differ among the groups (Fig 5E and 5F).

Bottom Line: H/R was accompanied by a small increase in LDH and non-significant increase in cTnI.SNAP and BNP showed small but significant protective effects during reoxygenation.The sensitivity of the model needs improvement.

View Article: PubMed Central - PubMed

Affiliation: Cardiovascular Research Group, Department of Biochemistry, University of Szeged, Szeged, Hungary; Pharmahungary Group, Szeged, Hungary.

ABSTRACT
In vitro assays could replace animal experiments in drug screening and disease modeling, but have shortcomings in terms of functional readout. Force-generating engineered heart tissues (EHT) provide simple automated measurements of contractile function. Here we evaluated the response of EHTs to hypoxia/reoxygenation (H/R) and the effect of known cardiocytoprotective molecules. EHTs from neonatal rat heart cells were incubated for 24 h in EHT medium. Then they were subjected to 180 min hypoxia (93% N2, 7% CO2) and 120 min reoxygenation (40% O2, 53% N2, 7% CO2), change of medium and additional follow-up of 48 h. Time-matched controls (40% O2, 53% N2, 7% CO2) were run for comparison. The following conditions were applied during H/R: fresh EHT medium (positive control), the NO-donor S-nitroso-N-acetyl-D,L-penicillamine (SNAP, 10(-7), 10(-6), 10(-5) M) or the guanylate cyclase activator brain type natriuretic peptide (BNP, 10(-9), 10(-8), 10(-7) M). Frequency and force of contraction were repeatedly monitored over the entire experiment, pH, troponin I (cTnI), lactate dehydrogenase (LDH) and glucose concentrations measured in EHT medium. Beating activity of EHTs in 24 h-medium ceased during hypoxia, partially recovered during reoxygenation and reached time-control values during follow-up. H/R was accompanied by a small increase in LDH and non-significant increase in cTnI. In fresh medium, some EHTs continued beating during hypoxia and all EHTs recovered faster during reoxygenation. SNAP and BNP showed small but significant protective effects during reoxygenation. EHTs are applicable to test potential cardioprotective compounds in vitro, monitoring functional and biochemical endpoints, which otherwise could be only measured by using in vivo or ex vivo heart preparations. The sensitivity of the model needs improvement.

No MeSH data available.


Related in: MedlinePlus