Department of Biomedical Physiology and Kinesiology, Simon Fraser University, Burnaby, British Columbia, Canada.
Department of Pharmacology and Toxicology, Alexandria University, Alexandria, Egypt.
Br J Pharmacol. 2022 Dec;179(24):5259-5272. doi: 10.1111/bph.15936. Epub 2022 Aug 16.
Sepsis, caused by a dysregulated response to infections, can lead to cardiac arrhythmias. However, the mechanisms underlying sepsis-induced inflammation, and how inflammation provokes cardiac arrhythmias, are not well understood. We hypothesized that cannabidiol (CBD) may ameliorate lipopolysaccharide (LPS)-induced cardiotoxicity, via Toll-like receptors (TLR4) and cardiac sodium channels (Na 1.5).
We incubated human immune cells (THP-1 macrophages) with LPS for 24 h, then extracted the THP-1 incubation media. ELISA assays showed that LPS (1 or 5 μg·ml ), in a concentration-dependent manner, or MPLA (TLR4 agonist, 5 μg·ml ) stimulated the THP-1 cells to release inflammatory cytokines (TNF-α and IL-6). Prior incubation (4 h) with CBD (5 μM) or C34 (TLR4 antagonist: 5 μg·ml ) inhibited LPS and MPLA-induced release of both IL-6 and TNF-α. Human-induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CM) were subsequently incubated for 24 h in the media extracted from THP-1 cells incubated with LPS, MPLA alone, or in combination with CBD or C34. Voltage-clamp experiments showed a right shift in the voltage dependence of Na 1.5 activation, steady state fast inactivation (SSFI), increased persistent current and prolonged in silico action potential duration in hiSPC-CMs incubated in the LPS or MPLA-THP-1 media. Co-incubation with CBD or C34 rescued the biophysical dysfunction caused by LPS and MPLA.
Our results suggest that CBD may protect against sepsis-induced inflammation and subsequent arrhythmias through (i) inhibition of the release of inflammatory cytokines, antioxidant and anti-apoptotic effects and/or (ii) a direct effect on Na 1.5.
脓毒症是由感染引起的失调反应导致的，可导致心律失常。然而，脓毒症引起的炎症的机制，以及炎症如何引发心律失常，尚不清楚。我们假设大麻二酚（CBD）可能通过 Toll 样受体（TLR4）和心脏钠离子通道（Na 1.5）改善脂多糖（LPS）诱导的心肌毒性。
我们将人免疫细胞（THP-1 巨噬细胞）与 LPS 孵育 24 小时，然后提取 THP-1 孵育培养基。ELISA 检测显示，LPS（1 或 5 μg·ml ）呈浓度依赖性，或 MPLA（TLR4 激动剂，5 μg·ml ）刺激 THP-1 细胞释放炎症细胞因子（TNF-α 和 IL-6）。CBD（5 μM）或 C34（TLR4 拮抗剂：5 μg·ml ）预先孵育（4 小时）可抑制 LPS 和 MPLA 诱导的 IL-6 和 TNF-α的释放。随后，将人诱导多能干细胞衍生的心肌细胞（hiPSC-CM）在 LPS、MPLA 单独或与 CBD 或 C34 联合孵育的 THP-1 细胞提取的培养基中孵育 24 小时。电压钳实验显示，在 LPS 或 MPLA-THP-1 培养基中孵育的 hiPSC-CM 中，Na 1.5 激活、稳态快速失活（SSFI）、持续电流增加和虚拟动作电位持续时间延长的电压依赖性右移。与 CBD 或 C34 共孵育可挽救 LPS 和 MPLA 引起的生物物理功能障碍。
我们的研究结果表明，CBD 可能通过以下两种方式来预防脓毒症引起的炎症和随后的心律失常：（i）抑制炎症细胞因子的释放、抗氧化和抗凋亡作用，和/或（ii）直接作用于 Na 1.5。
