Cynodon dactylon and Sida acuta extracts impact on the function of the cardiovascular system in zebrafish embryos

Abstract

The aim of the present study was to screen cardioactive herbs from Western Ghats of India. The heart beat rate (HBR) and blood flow during systole and diastole were tested in zebrafish embryos. We found that Cynodon dactylon (C. dactylon) induced increases in the HBR in zebrafish embryos with a HBR of (3.968±0.344) beats/s, which was significantly higher than that caused by betamethosone [(3.770±0.344) beats/s]. The EC50 value of C. dactylon was 3.738 µg/mL. The methanolic extract of Sida acuta (S. acuta) led to decreases in the HBR in zebrafish embryos [(1.877±0.079) beats/s], which was greater than that caused by nebivolol (positive control). The EC50 value of Sida acuta was 1.195 µg/mL. The untreated embryos had a HBR of (2.685±0.160) beats/s at 3 d post fertilization (dpf). The velocities of blood flow during the cardiac cycle were (2,291.667±72.169) µm/s for the control, (4,250±125.000) µm/s for C. dactylon and (1,083.333±72.169) µm/s for S. acuta. The LC50 values were 32.6 µg/mL for C. dactylon and 20.9 µg/mL for S. acuta. In addition, the extracts exhibited no chemical genetic effects in the drug dosage range tested. In conclusion, we developed an assay that can measure changes in cardiac function in response to herbal small molecules and determine the cardiogenic effects by microvideography.

Upper thermal tolerance of closely related Danio species

“…rerio appear to have the capacity to double f H at 28° C. Embryonic f H for D . rerio at 28° C is around 238 beats min −1 (Kannan & Vincent, ), which is near the f Hmax measured here at 28° C, but resting f H decreases during development (Hu et al , ).…”

“…Neither Barrionuevo & Burggren (1999) nor Tsai et al (2011) measured f Hmax . Given the resting f H at 28 ∘ C is half the f Hmax (247⋅4 ± 4⋅5 beats min −1 ) measured in this study, D. rerio appear to have the capacity to double f H at 28 ∘ C. Embryonic f H for D. rerio at 28 ∘ C is around 238 beats min −1 (Kannan & Vincent, 2012), which is near the f Hmax measured here at 28 ∘ C, but resting f H decreases during development (Hu et al, 2000).…”

The effect of acute warming and thermal acclimation on maximum heart rate of the common killifish Fundulus heteroclitus

“…240 min −1 at 28°C and near 300 min −1 at 32°C. By comparison, Kannan and Vincent () also reported that resting f H in anaesthetised, embryonic zebrafish at 28°C was increased from around 140 to 238 min −1 by cardioactive drugs, suggesting that resting vagal tone can be appreciable in zebrafish. While we cannot be absolutely certain that MS‐222 did not affect T max and T arr data for f Hmax in killifish in our study, Jayasundara and Somero () also found that T arr was 0.2 − 1.9°C below CT max (for 26 and 9°C acclimated G. mirabilis , respectively) when conscious fish were acutely warmed.…”

Angiogenic effect of the aqueous extract of Cynodon dactylon on human umbilical vein endothelial cells and granulation tissue in rat

“…In another study this effect was also attributed to its anti-arrhythmic activity [ 14 ]. The plant also increased heart beat rate in a study on zebrafish with a potency greater than that of betamethasone [ 15 ].…”