Pemafibrate suppresses oxidative stress and apoptosis under cardiomyocyte ischemia-reperfusion injury in type 1 diabetes mellitus

Effects of Pemafibrate on Reducing Oxidative Stress and Augmenting Angiogenesis in Ischemic Limb Tissue

OBJECTIVE

Oxidative damage is observed in the ischemic limbs of patients with arteriosclerosis obliterans. We investigated whether pemafibrate, a selective peroxisome proliferator-activated receptor alpha modulator, reduced oxidative stress in ischemic limbs and consequently rescued limb damage in model mice.

MATERIALS AND METHODS

We surgically induced hind-limb ischemia in mice and orally administered pemafibrate solution (P-05 group, 0.5 mg/kg/day; P-10 group, 1.0 mg/kg/day) or control solution (control group). Seven days after the surgery, differences in reactive oxygen species (ROS) contents, antioxidative enzyme and transcription factor expression, blood flow, and capillary density in ischemic limbs were assessed.

RESULTS

Tissue ROS levels were lower in the P-05 and P-10 groups compared with those in the control group. Although the tissue expression levels of nuclear factor-erythroid 2-related factor 2 increased in the P-10 group compared with that in the control group, no corresponding changes were observed in the tissue expression of four antioxidative enzymes. The limb salvage rates and capillary densities in ischemic limbs were higher in the P-05 and P-10 groups than that in the control group.

CONCLUSION

Pemafibrate treatment reduced oxidative stress and augmented angiogenesis in ischemic limbs, contributing to prevention of limb damage in mice.

Molecular mechanisms and therapeutic perspectives of peroxisome proliferator-activated receptor α agonists in cardiovascular health and disease

The prevalence of cardiovascular disease (CVD) has been rising due to sedentary lifestyles and unhealthy dietary patterns. Peroxisome proliferator-activated receptor α (PPARα) is a nuclear receptor regulating multiple biological processes, such as lipid metabolism and inflammatory response critical to cardiovascular homeostasis. Healthy endothelial cells (ECs) lining the lumen of blood vessels maintains vascular homeostasis, where endothelial dysfunction associated with increased oxidative stress and inflammation triggers the pathogenesis of CVD. PPARα activation decreases endothelial inflammation and senescence, contributing to improved vascular function and reduced risk of atherosclerosis. Phenotypic switch and inflammation of vascular smooth muscle cells (VSMCs) exacerbate vascular dysfunction and atherogenesis, in which PPARα activation improves VSMC homeostasis. Different immune cells participate in the progression of vascular inflammation and atherosclerosis. PPARα in immune cells plays a critical role in immunological events, such as monocyte/macrophage adhesion and infiltration, macrophage polarization, dendritic cell (DC) embedment, T cell activation, and B cell differentiation. Cardiomyocyte dysfunction, a major risk factor for heart failure, can also be alleviated by PPARα activation through maintaining cardiac mitochondrial stability and inhibiting cardiac lipid accumulation, oxidative stress, inflammation, and fibrosis. This review discusses the current understanding and future perspectives on the role of PPARα in the regulation of the cardiovascular system as well as the clinical application of PPARα ligands.

Pemafibrate inhibited renal dysfunction and fibrosis in a mouse model of adenine-induced chronic kidney disease

AIMS

Peroxisome proliferator-activated receptor-alpha (PPARα) levels are markedly lower in the kidneys of chronic kidney disease (CKD) patients. Fibrates (PPARα agonists) are therapeutic agents against hypertriglyceridemia and potentially against CKD. However, conventional fibrates are eliminated by renal excretion, limiting their use in patients with impaired renal function. Here, we aimed to evaluate the renal risks associated with conventional fibrates via clinical database analysis and investigate the renoprotective effects of pemafibrate, a novel selective PPARα modulator mainly excreted into the bile.

MAIN METHODS

The risks associated with conventional fibrates (fenofibrate, bezafibrate) to the kidneys were evaluated using the Food and Drug Administration Adverse Event Reporting System. Pemafibrate (1 or 0.3 mg/kg/day) was administered daily using an oral sonde. Its renoprotective effects were examined in unilateral ureteral obstruction (UUO)-induced renal fibrosis model mice (UUO mice) and adenine-induced CKD model mice (CKD mice).

KEY FINDINGS

The ratios of glomerular filtration rate decreased and blood creatinine increased were markedly higher after conventional fibrate use. Pemafibrate administration suppressed increased gene expressions of collagen-I, fibronectin, and interleukin 1 beta (IL-1β) in the kidneys of UUO mice. In CKD mice, it suppressed increased plasma creatinine and blood urea nitrogen levels and decreased red blood cell count, hemoglobin, and hematocrit levels, along with renal fibrosis. Moreover, it inhibited the upregulation of monocyte chemoattractant protein-1, IL-1β, tumor necrosis factor-alpha, and IL-6 in the kidneys of CKD mice.

SIGNIFICANCE

These results demonstrated the renoprotective effects of pemafibrate in CKD mice, confirming its potential as a therapeutic agent for renal disorders.

Effects of pemafibrate on primary biliary cholangitis with dyslipidemia

AIM

The purpose of this study was to examine the effect of pemafibrate (PEM) in primary biliary cholangitis (PBC) patients with dyslipidemia.

METHODS

Patients who were diagnosed with PBC between June 2018 and December 31, 2020 were included in the study if they also had dyslipidemia and their alkaline phosphatase (ALP) or gamma-glutamyl transferase (GGT) levels remained above the normal range despite taking 600 mg/day ursodeoxycholic acid (UDCA) for at least 6 months. Patients who were treated with UDCA alone were administered PEM as an add-on (PEM-add group), and patients who were treated with UDCA and bezafibrate (BEZ) for at least 6 months were given PEM instead of BEZ (PEM-switch group). Clinical parameters were compared in all patients, and the levels of ALP, GGT, the estimated glomerular filtration rate (eGFR), and creatinine (Cr) were compared between the PEM-add and PEM-switch groups. Improvement in cholangitis was also evaluated.

RESULTS

In the PEM-add group, both ALP and GGT improved in 40 of 46 patients (87.0%). In the PEM-switch group, both ALP and GGT improved in 15 of 29 patients (51.7%). In the PEM-switch group, however, significant improvement was seen in eGFR and Cr.

CONCLUSIONS

Administration of PEM is effective in PBC patients with dyslipidemia who are refractory to UDCA monotherapy. In patients using both UDCA and BEZ, there was an advantage in switching to PEM if they had renal damage; however, improvement of ALP and GGT occurred in about 50%.

Cardioprotective effects of Sinomenine in myocardial ischemia/reperfusion injury in a rat model

Background

Ischemia reperfusion (I/R) play an imperative role in the expansion of cardiovascular disease. Sinomenine (SM) has been exhibited to possess antioxidant, anticancer, anti-inflammatory, antiviral and anticarcinogenic properties. The aim of the study was scrutinized the cardioprotective effect of SM against I/R injury in rat.

Methods

Rat were randomly divided into normal control (NC), I/R control and I/R + SM (5, 10 and 20 mg/kg), respectively. Ventricular arrhythmias, body weight and heart weight were estimated. Antioxidant, inflammatory cytokines, inflammatory mediators and plasmin system indicator were accessed.

Results

Pre-treated SM group rats exhibited the reduction in the duration and incidence of ventricular fibrillation, ventricular ectopic beat (VEB) and ventricular tachycardia along with suppression of arrhythmia score during the ischemia (30 and 120 min). SM treated rats significantly (P < 0.001) altered the level of antioxidant parameters. SM treatment significantly (P < 0.001) repressed the level of creatine kinase MB (CK-MB), creatine kinase (CK) and troponin I (Tnl). SM treated rats significantly (P < 0.001) repressed the tissue factor (TF), thromboxane B2 (TXB2), plasminogen activator inhibitor 1 (PAI-1) and plasma fibrinogen (Fbg) and inflammatory cytokines and inflammatory mediators.

Conclusion

Our result clearly indicated that SM plays anti-arrhythmia effect in I/R injury in the rats via alteration of oxidative stress and inflammatory reaction.

The adiponectin signalling pathway - A therapeutic target for the cardiac complications of type 2 diabetes?

Diabetes is associated with an increased risk of heart failure (HF). This is commonly termed diabetic cardiomyopathy and is often characterised by increased cardiac fibrosis, pathological hypertrophy, increased oxidative and endoplasmic reticulum stress as well as diastolic dysfunction. Adiponectin is a cardioprotective adipokine that is downregulated in settings of type 2 diabetes (T2D) and obesity. Furthermore, both adiponectin receptors (AdipoR1 and R2) are also downregulated in these settings which further results in impaired cardiac adiponectin signalling and reduced cardioprotection. In many cardiac pathologies, adiponectin signalling has been shown to protect against cardiac remodelling and lipotoxicity, however its cardioprotective actions in T2D-induced cardiomyopathy remain unresolved. Diabetic cardiomyopathy has historically lacked effective treatment options. In this review, we summarise the current evidence for links between the suppressed adiponectin signalling pathway and cardiac dysfunction, in diabetes. We describe adiponectin receptor-mediated signalling pathways that are normally associated with cardioprotection, as well as current and potential future therapeutic approaches that could target this pathway as possible interventions for diabetic cardiomyopathy.