Antiapoptotic potential of herbal drugs in cardiovascular disorders: an overview

Resveratrol protects against myocardial ischemic injury via the inhibition of NF‑κB‑dependent inflammation and the enhancement of antioxidant defenses

Resveratrol (RES) is a natural phenol which possesses multiple pharmacological actions. The present study aimed to determine whether RES protects against myocardial ischemic injury in association with the inhibition of NF‑κB‑dependent inflammation and the enhancement of antioxidant defenses in mice following acute myocardial infarction (AMI). Male C57/BL mice were randomly assigned to 3 groups as follows: The sham‑operated (sham) group, AMI + vehicle group and AMI + RES group. Rat H9C2 cells were also used to examine the effects of RES on hypoxia‑induced oxidative injury in vitro. Redox homeostasis in the mouse myocardium and rat H9C2 cells was determined post‑treatment. The mRNA and protein levels of phosphorylated (p‑)IκB kinase (p‑IKK), p‑nuclear factor (NF)‑κB p65, interleukin (IL)‑1β, IL‑6, nerve growth factor (NGF) and insulin‑like growth factor‑1 (IGF‑1) were measured by RT‑qPCR and western blot analysis. It was found that RES slightly protected the myocardium against ischemic injury in mice, while it prevented the hypoxia‑induced apoptosis of H9C2 cells. RES decreased the production of reactive oxygen species (ROS) and enhanced the activities of superoxide dismutase (SOD), glutathione (GSH) and glutathione peroxidase (GPx). RES also downregulated the protein and/or mRNA levels of p‑IKK, p‑NF‑κB p65, IL‑1β, IL‑6, NGF and IGF‑1 at 7 and 28 days after infarction. On the whole, these data indicate that RES protects the myocardium against ischemic injury in association with the inhibition of oxidative stress and inflammatory responses. Thus, RES has the potential to be used as an adjunctive therapeutic drug for heart diseases.

Composition and cardioprotective effects of Primula veris L. solid herbal extract in experimental chronic heart failure

BACKGROUND

High interest in chronic heart failure (CHF) is accounted for by its high incidence, poor prognosis, growing number of hospital admissions due to the heart failure relapse, and inadequate treatment. These facts necessitate a search for new pharmacological agents for the CHF correction. Herbal medicinal products appear to be very promising as they have a noticeable therapeutic effect and tend to be more harmless in comparison to the most of synthesized medications.

PURPOSE

Our aim was to study the composition of the Primula veris L. solid herbal extract (PVSHE) and its effects on the myocardial contractile function in animals with experimental CHF.

STUDY DESIGN

The study design involved the identification of the raw material composition of the P. veris L. extract. For the experimental part of our research, we used the model of CHF to elucidate the cardioprotective properties of PVSHE.

METHODS

The active extract constituents were isolated by thin-layer chromatography and column chromatography; the extract components were identified by high-performance liquid chromatography, ultraviolet spectroscopy (UVS), and nuclear magnetic resonance spectroscopy (NMRS). To model CHF, L-isoproterenol at a dose of 2.5 mg/kg was intraperitoneally injected to the experimental rats twice a day for 21 days. Cardiac output was assessed with the loading test, adrenoreactivity test, and maximum isometric loading test; CHF markers adrenomedullin and copeptin were detected in blood plasma with ELISA kit for adrenomedullin and copeptin (Coud-Clone Corp., USA).

RESULTS

P. veris L. solid herbal extract contains flavonoid aglycons (apigenin, quercetine, kaemferol), flavonoid glycosides (cinarozid, rutin, hyperozid), as well as polymethoxylated flavonoids acting as chemotaxonomic markers for the genus Primula (8-methoxy-flavone; 3',4'methylenedioxy-5'-methoxyflavone). The substance 3',4'methylenedioxy-5'-methoxyflavone has been isolated from the primrose herb for the first time. We showed that the PVSHE has a cardioprotective effect when it was administered at a dose of 30 mg/kg in the experimental CHF, as evidenced by a lower number of animal death, lower level of CHF markers in the blood plasma of the experimental animals, the higher increase in rate of myocardial contraction and relaxation, the higher level of left ventricular pressure (LVP) and of maximum intensity of structural performance (MISP), as compared to the control group.

CONCLUSION

P. veris L. solid herbal extract contains flavonoid aglycons, flavonoid glycosides, and polymethoxylated flavonoids. The herbal agent increases the myocardial contractility in experimental CHF.

Evaluation of anticancer potential of Bacopa monnieri L. against MCF-7 and MDA-MB 231 cell line

Background:

The ethanolic extract of Bacopa monnieri contains bacoside A and B, brahmin, cucurbitacins, and betulinic acid. Currently, cucurbitacins have also been reported for their strong anti-tumorigenic and anti-proliferative activity by inducing cell cycle arrest at the G₂/M phase and formation of multiplied cells. The present study was carried out to evaluate the in vitro cytotoxic activity of ethanolic extract of dichloromethane (DCM) fraction of B. monnieri on two different cell lines.

Materials and Methods:

The ethanolic extract of B. monnieri was prepared using soxhlet extraction method and different fractions (hexane, DCM, methanol, acetone, and water) of ethanolic extracts were prepared. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay of ethanolic extract and of all fractions was carried out on MCF-7 and MDA-MB 231 cell lines. The presence of cucurbitacins and betulinic acid in these fractions was confirmed by high-performance thin layer chromatography.

Results:

The IC₅₀ values of ethanolic extract of B. monnieri in MCF-7 and MDA-MB 231 cell lines were 72.0 μg/mL and 75.0 μg/mL, respectively. The DCM fraction of B. monnieri showed maximum cytotoxic activity among all fraction upto 72 h and was found to be 57.0 μg/mL and 42.0 μg/mL, respectively.

Conclusion:

The results showed good cytotoxic activity in DCM fraction in both the cell lines may be due to the presence of cucurbitacins and betulinic acid in DCM fraction.

Apple pectin, a dietary fiber, ameliorates myocardial injury by inhibiting apoptosis in a rat model of ischemia/reperfusion

BACKGROUND/OBJECTIVE

Myocardial cell death due to occlusion of the coronary arteries leads to myocardial infarction, a subset of coronary heart disease (CHD). Dietary fiber is known to be associated with a reduced risk of CHD, the underlying mechanisms of which were suggested to delay the onset of occlusion by ameliorating risk factors. In this study, we tested a hypothesis that a beneficial role of dietary fiber could arise from protection of myocardial cells against ischemic injury, manifested after occlusion of the arteries.

MATERIALS/METHODS

Three days after rats were fed apple pectin (AP) (with 10, 40, 100, and 400 mg/kg/day), myocardial ischemic injury was induced by 30 min-ligation of the left anterior descending coronary artery, followed by 3 hr-reperfusion. The area at risk and infarct area were evaluated using Evans blue dye and 2,3,5-triphenyltetrazolium chloride (TTC) staining, respectively. DNA nicks reflecting the extent of myocardial apoptosis were assessed by TUNEL assay. Levels of cleaved caspase-3, Bcl-2, and Bax were assessed by immunohistochemistry.

RESULTS

Supplementation of AP (with 100 and 400 mg/kg/day) resulted in significantly attenuated infarct size (IS) (ratio of infarct area to area at risk) by 21.9 and 22.4%, respectively, in the AP-treated group, compared with that in the control group. This attenuation in IS showed correlation with improvement in biomarkers involved in the apoptotic cascades: reduction of apoptotic cells, inhibition of conversion of procaspase-3 to caspase-3, and increase of Bcl-2/Bax ratio, a determinant of cell fate.

CONCLUSIONS

The findings indicate that supplementation of AP results in amelioration of myocardial infarction by inhibition of apoptosis. Thus, the current study suggests that intake of dietary fiber reduces the risk of CHD, not only by blocking steps leading to occlusion, but also by protecting against ischemic injury caused by occlusion of the arteries.

Protective role of Aralia elata polysaccharide on mercury(II)-induced cardiovascular oxidative injury in rats

Mercury(II) is a highly toxic environmental pollutant leading to oxidative stress in animals and human beings. In this study we aimed to investigate the possible protective effect of a water-soluble polysaccharide (AEP-w1) from the root bark of Aralia elata against experimental mercury(II)-induced cardiovascular oxidative injury in rat model. The results showed that delayed AEP-w1 supplement to HgCl2-treated mice not only decreased serum lactate dehydrogenase (LDH) and tumor necrosis factor-α (TNF-α) levels, but also increased serum nitric oxide (NO) metabolite levels and antioxidant capacity. Moreover, AEP-w1 administration to HgCl2-treated mice significantly decreased malondialdehyde (MDA) level and myeloperoxidase (MPO) activity and increased superoxide dismutase (SOD) and catalase (CAT) activities, along with glutathione (GSH) level in rat cardiac tissue. In addition, elevated serum aspartate aminotransferase (AST), alanine aminotransferase (ALT), blood urea nitrogen (BUN) and creatinine (Cr) levels in the saline-treated Hg group were also reversed by AEP-w1 treatment. Therefore, the present study demonstrates that alleviation of HgCl2-induced oxidative injury in rat by AEP-w1 contributes to better understanding of its beneficial effect against cardiovascular diseases.

Methanol Extract of Cassia mimosoides var. nomame Attenuates Myocardial Injury by Inhibition of Apoptosis in a Rat Model of Ischemia-Reperfusion

Interruption of blood flow through coronary arteries and its subsequent restoration triggers the generation of a burst of reactive oxygen species (ROS), leading to myocardial cell death. In this study, we determined whether a methanol extract of Cassia mimosoides var. nomame Makino could prevent myocardial ischemia-reperfusion injury. When radical scavenging activity of the extract was measured in vitro using its α,α-diphenyl-β-picrylhydrazyl (DPPH) radical quenching ability, the extract showed an activity slightly lower than that of ascorbic acid. Three days after oral administration of the extract (400 mg/kg/day) to rats, myocardial ischemia/reperfusion injury was generated by 30 min of ligation of the left anterior descending coronary artery (LAD), followed by 3 hr reperfusion. Compared with the vehicle-treated group, administration of the extract significantly reduced infarct size (IS) (ratio of infarct area to area at risk) in the extract-treated group by 28.3%. Reduction in the cellular injury was mediated by attenuation of Bax/Bcl-2 ratio by 33.3%, inhibition of caspase-3 activation from procas-pase-3 by 40%, and subsequent reduction in the number of apoptotic cells by 66.3%. These results suggest that the extract attenuates myocardial injury in a rat model of ischemia-reperfusion by scavenging ROS, including free radicals, and consequently blocking apoptotic cascades. Therefore, intake of Cassia mimosoides var. nomame Makino might be beneficial for preventing ischemic myocardial injury.