Bhaskaran Sreenath Kunnathupara, Kannappan Poornima
Department of Biochemistry, Karpagam University, Karpagam Academy of Higher Education, Coimbatore 641 021, Tamil Nadu, India.
Department of Biochemistry, Karpagam University, Karpagam Academy of Higher Education, Coimbatore 641 021, Tamil Nadu, India.
Biomed Pharmacother. 2017 May;89:473-481. doi: 10.1016/j.biopha.2017.01.177. Epub 2017 Feb 27.
Azolla microphylla is an important fast-growing aquatic plant trusted for its agronomic, nutritious and therapeutic uses. The present work is undertaken to investigate the protective effect of the ethanolic extract of Azolla microphylla (EAM) against the Isoproterenol (ISO) induced cardiotoxicity in rats. Rats were pre-treated with EAM (250 and 500mg/kg b.w.) for 28 days along with ISO (85mg/kg; s.c.) on the 29th and 30th days. ISO-induced rats displayed significant diminution in cardiac antioxidant enzymes activities, increased lipid peroxidation and alteration in cardiac marker enzymes. The same group also displayed an increase in levels of serum lipid profiles and pro-inflammatory cytokines (IL-6 and IL-8) accompanied with a significant reduction in the anti-inflammatory cytokine levels (IL-10). Moreover, the histopathological investigations in the heart tissue of ISO-induced group exhibited myocardial necrosis and inflammation, which correlated with the increased immunoreactivity for Bax/iNOS, whereas an absence of reactivity for Bcl-2 proteins. However, in EAM pre-treated rats, the activities of antioxidant enzymes, cardiac marker enzymes, membrane-bound ATPases together with the levels of lipid profile, non-enzymatic antioxidants, pro and anti-inflammatory cytokines were maintained at normalcy that was further supported by improving histopathological changes and myocardial architecture. The IHC results of EAM pre-treated rats indicate up-regulated and down-regulated expressions of Bcl-2 and Bax/iNOS proteins, respectively. Thus, the present study reveals that A. microphylla alleviates myocardial damage in ISO-induced cardiac injury and demonstrates cardioprotective potential which could be attributed to its potent antioxidant and free radical scavenging activity. A possible mechanism for the protective effect is the elevated expression of endogenous antioxidant defense enzymes, anti-inflammatory cytokines, degraded lipid peroxidation products and improved energy metabolism of cardiac mitochondria, thus attenuating necrosis of the myocytes.
小叶满江红是一种重要的速生水生植物，因其在农艺、营养和治疗方面的用途而备受信赖。本研究旨在探讨小叶满江红乙醇提取物（EAM）对异丙肾上腺素（ISO）诱导的大鼠心脏毒性的保护作用。大鼠连续28天接受EAM（250和500mg/kg体重）预处理，并在第29天和第30天同时接受ISO（85mg/kg；皮下注射）。ISO诱导的大鼠心脏抗氧化酶活性显著降低，脂质过氧化增加，心脏标志物酶发生改变。同一组大鼠的血清脂质谱和促炎细胞因子（IL-6和IL-8）水平也有所升高，同时抗炎细胞因子水平（IL-10）显著降低。此外，ISO诱导组心脏组织的组织病理学检查显示心肌坏死和炎症，这与Bax/iNOS免疫反应性增加相关，而Bcl-2蛋白无反应性。然而，在EAM预处理的大鼠中，抗氧化酶、心脏标志物酶、膜结合ATP酶的活性以及脂质谱、非酶抗氧化剂、促炎和抗炎细胞因子的水平均维持在正常水平，组织病理学变化和心肌结构的改善进一步支持了这一点。EAM预处理大鼠的免疫组化结果表明，Bcl-2和Bax/iNOS蛋白的表达分别上调和下调。因此，本研究表明小叶满江红可减轻ISO诱导的心脏损伤中的心肌损伤，并显示出心脏保护潜力，这可能归因于其强大的抗氧化和自由基清除活性。保护作用的一个可能机制是内源性抗氧化防御酶、抗炎细胞因子的表达升高，脂质过氧化产物降解以及心脏线粒体能量代谢改善，从而减轻心肌细胞坏死。
