Objective To investigate effects of fistular onion bulb extract (FOB) preventing ischemia/reperfusion (I/R) injury in cardiomyocytes of streptozotocin-induced diabetes mellitus rats.
Methods Diabetes rats by streptozotocin-induced were fed FOB (100 g/kg/day) from six to 14 week of age. Hearts models of I/R which randomly divided into control group, diabetes group, FOB control and diabetes groups were observed changes of heart function through using Langendorff-perfusion system. Fluorescence intensity of intracellular Ca2+ was detected with Flup-3/AM loading by laser scanning confocal microscope. ICa-L was recorded via whole-cell patch clamp technique in enzymatically dissociated single cardiomyocytes.
Results In diabetes group, values of LVDP, LVEDP, (dp/dtmax) and CF were all significantly decreased, and dp/dtmin were increased (compared with normal control group, p<0.01, respectively). But every parameter mentioned above such as LVDP, LVEDP, dp/dtmax, CF was increased, and dp/dtmin was obviously decreased in FOB diabetes group (compared with diabetes group, p<0.01, respectively). Fluorescence intensities of intracellular free Ca2+ were markedly stronger after influence of I/R injury (compared with normal control group, p<0.01). Current density of ICa-L was significantly decreased, and I–V curve was changed up to the top, as soon as the peak clamp potential was −30 mV with same I/R condition in diabetes rats. In FOB diabetes group, fluorescence intensities of intracellular free Ca2+ were significantly reduced in I/R injury procedure (compared with diabetes group, p<0.01). ICa-L was partly recovered near normal control group, and I–V curve was changed among normal control and diabetes group. When clamp voltage was −20 mV, the current densities of ICa-L were significantly decreased from (−8.17±2.07) pA/pF in normal control group to (−3.21±0.54)pA/pF in diabetes group (p<0.01). (−7.14±2.17) pA/pF in FOB control group (compared with normal control, p>0.05, and (−6.81±0.76) pA/pF in FOB diabetes (compared with normal group, p<0.05, and with diabetes group, p<0.01, and with FOB control group, p>0.05).
Conclusion Poor heart function was tightly correlate to that (Ca2+)i was increased and ICa-L was decreased with I/R injury in diabetes rat hearts. FOB- treated could significantly inhibit I/R injury induced severely cardiac performance, which was attributed to that FOB might adjust ICa-L influx, and normalise balance of intercellular (Ca2+)i, as soon as blocked Ca2+ overload trigged by effects of Ca2+-induced Ca2+ release in diabetes cardiomyocytes.
Statistics from Altmetric.com
If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.