Supplementation with psyllium seed husk reduces myocardial damage in a rat model of ischemia/reperfusion

Abstract

BACKGROUND/OBJECTIVES Myocardial infarction (MI) is caused by extensive myocardial damage attributed to the occlusion of coronary arteries. Our previous study in a rat model of ischemia/reperfusion (I/R) demonstrated that administration of arabinoxylan (AX), comprising arabinose and xylose, protects against myocardial injury. In this study, we undertook to investigate whether psyllium seed husk (PSH), a safe dietary fiber containing a high level of AX (> 50%), also imparts protection against myocardial injury in the same rat model. MATERIALS/METHODS Rats were fed diets supplemented with PSH (1, 10, or 100 mg/kg/d) for 3 d. The rats were then subjected to 30 min ischemia through ligation of the left anterior descending coronary artery, followed by 3 h reperfusion through release of the ligation. The hearts were harvested and cut into four slices. To assess infarct size (IS), an index representing heart damage, the slices were stained with 2,3,5-triphenyltetrazolium chloride (TTC). To elucidate underlying mechanisms, Western blotting was performed for the slices. RESULTS Supplementation with 10 or 100 mg/kg/d of PSH significantly reduces the IS. PSH supplementation (100 mg/kg/d) tends to reduce caspase-3 generation and increase BCL-2/BAX ratio. PSH supplementation also upregulates the expression of nuclear factor erythroid 2-related factor 2 (NRF2), and its target genes including antioxidant enzymes such as glutathione S-transferase mu 2 (GSTM2) and superoxide dismutase 2 (SOD2). PSH supplementation upregulates some sirtuins (NAD + -dependent deacetylases) including SIRT5 (a mitochondrial sirtuin) and SIRT6 and SIRT7 (nuclear sirtuins). Finally, PSH supplementation upregulates the expression of protein kinase A (PKA), and increases phosphorylated cAMP response element-binding protein (CREB) (pCREB), a target protein of PKA. CONCLUSIONS The results from this study indicate that PSH consumption reduces myocardial I/R injury in rats by inhibiting the apoptotic cascades through modulation of gene expression of several genes located upstream of apoptosis. Therefore, we believe that PSH can be developed as a functional food that would be beneficial in the prevention of MI.

miR‐496 remedies hypoxia reoxygenation–induced H9c2 cardiomyocyte apoptosis via Hook3‐targeted PI3k/Akt/mTOR signaling pathway activation

“…In addition, we found that miR‐496 overexpression could inhibit H/R‐induced cell apoptosis, whereas, miR‐496 inhibition could promote H/R‐induced cell apoptosis (Figure A‐D). It reported that miR‐496 overexpression reduced cerebral I/R injury by inhibiting the expression level of Bcl‐2 family proteins, in addition, proliferation indicators, such as PCNA and Ki67, decreased in I/R damage model, and activated caspase‐3 promoted myocardial apoptosis in IRI . Our results showed that miR‐496 overexpression reduced the H/R‐induced inhibition of PCNA, Ki67, and Bcl‐2, and H/R‐induced increased of caspase‐3 and Bax.…”

“…It reported that miR-496 overexpression reduced cerebral I/R injury by inhibiting the expression level of Bcl-2 family proteins, 20 in addition, proliferation indicators, such as PCNA and Ki67, decreased in I/R damage model, 21 and activated caspase-3 promoted myocardial apoptosis in IRI. 22,23 Our results showed that miR-496 overexpression reduced the H/R-induced inhibition of PCNA, Ki67, and Bcl-2, and H/R-induced increased of caspase-3 and Bax. Therefore, miR-496 overexpression promoted cell viability and inhibited cell apoptosis via upregulating the proliferation and antiapoptosis protein expressions and downregulating proapoptosis protein expressions (Figure 2E and 2F).…”

Beneficial effects of psyllium on the prevention and treatment of cardiometabolic diseases

“…One study indicated that psyllium can enhance the expression of Nrf2, thereby increasing the levels of antioxidant enzymes such as glutathione S-transferase mu 2 (GSTM2) and superoxide dismutase 2 (SOD2), and enhancing the expression of SIRT5, SIRT6, and SIRT7, which contributes to protecting against myocardial ischemia/reperfusion injury through the elimination of ROS. 97 Diabetic retinopathy is envisioned as a biomarker of generalized hyperglycemic damage in the microvasculature. 98 The mechanisms of hyperglycemia leading to diabetic retinopathy mainly include increased free radical production, AGEs, inflammatory factors, and vascular endothelial growth factor.…”

“…One study indicated that psyllium can enhance the expression of Nrf2, thereby increasing the levels of antioxidant enzymes such as glutathione S -transferase mu 2 (GSTM2) and superoxide dismutase 2 (SOD2), and enhancing the expression of SIRT5, SIRT6, and SIRT7, which contributes to protecting against myocardial ischemia/reperfusion injury through the elimination of ROS. 97…”

A Comprehensive Analysis into the Therapeutic Application of Natural Products as SIRT6 Modulators in Alzheimer’s Disease, Aging, Cancer, Inflammation, and Diabetes

“…% of PSH. The mechanism of SIRT6 stimulation by PSH might be the binding of pCREB to the binding site CRE on SIRT6 gene promoter ( [106]. Arabinoxylan has been reported to produce immunomodulating and anticancer action in human immune cells (U937) and in gastric cancer cells ( [105,107].…”