Electrophysiological and mechanical effects of caffeic acid phenethyl ester, a novel cardioprotective agent with antiarrhythmic activity, in guinea-pig heart

Caffeic acid phenethyl ester ameliorates colistin-induced nephrotoxicity in rats via modulation of FOXO1/Nrf2/Sirt1 axis

BACKGROUND

Colistin (Cst) is one of the antimicrobial peptides and is reserved for use against multi-drug-resistant Gram-negative bacteria. However, the clinical value of Cst is limited by its nephrotoxic adverse effects. Caffeic acid phenethyl ester (CAPE) is a honeybee propolis flavonoid recognised for its diverse pharmacological potential. It has demonstrated d antioxidant and anti-inflammatory properties, as well as protective effects against chemically induced toxicity in variuos biological systems. This study aimed to investigate the impact of CAPE on nephrotoxicity induced in rats by Cst.

METHODS

Animals were randomly divided into five groups. Group 1 served as control, group 2 received CAPE (10 mg/kg) orally, group 3 received Cst IP, group 4 received Cst + CAPE (5 mg/kg) and group 5 received Cst + CAPE (10 mg/kg). All treatments were given daily for 10 consecutive days.

RESULTS

CAPE notably attenuated Cst-inducednephrotoxicity as shown by reducing urea serum levels, creatinine, cystatin C, urinary protein contents and urinary N-acetyl-β-D-glucosaminidase (NAG). This was confirmed by histological investigations that indicated amelioration of histopathological changes in the kidney architecture as well as the deposition of collagen in renal tissues. CAPE exhibited antioxidant effects supported by the prevention of rise in Cst-induced lipid peroxidation and depletion of superoxide dismutase and catalase enzymatic activities. In addition, CAPE inhibited the expression of the inflammatory markers including tumour necrosis factor-α, nuclear factor kappa B and interleukin-6. These actions were associated with modulation of messenger ribonucleic acid (mRNA) expression of Bax and Bcl-2 in favour of anti-apoptosis. CAPE inhibited Cst-induced rise in forkhead box O1 (FOXO1) expression and downregulation of nuclear factor erythroid 2-related factor 2 (Nrf2) and Sirtuin 1 (Sirt1) immune-expression.

CONCLUSION

CAPE protects against nephrotoxicity induced by Cst in ratsprimarily through its antioxidant, antiinflammatory and antiapoptotic activities. These pritective effects are mediated via modulation of FOXO1/Nrf2/Sirt1 axis.

Caffeic acid and its derivative caffeic acid phenethyl ester as potential therapeutic compounds for cardiovascular diseases: A systematic review

Cardiovascular diseases (CVDs) contribute to major public health issues. Some studies have found that caffeic acid (CA) and caffeic acid phenethyl ester (CAPE) may effectively prevent or treat CVDs. However, there is a major need to sum up our current understanding of the possible beneficial or detrimental effects of CA and CAPE on CVDs and related mechanisms. Therefore, this study aimed to summarize the data on this topic. A methodical search was carried out on key databases, including Pubmed, Google Scholar, Scopus, and Web of Science, from the beginning to June 2024. Studies were then assessed for eligibility based on inclusion and exclusion criteria. Treatment with CA and CAPE significantly and positively affected cardiovascular health in various aspects, including atherosclerotic diseases, myocardial infarction, hypertension, cardiac arrhythmias, and hypercoagulation state. Several mechanisms were proposed to mediate these effects, including transcription factors and signaling pathways associated with antioxidant, cytostatic, and anti-inflammatory processes. CA and CAPE were found to have several beneficial effects via multiple mechanisms during the prevention and treatment of various CVDs. However, these promising effects were only reported through in vitro and animal studies, which reinforces the need for further evaluation of these effects via human clinical investigations.

Cardiovascular Effects of Caffeic Acid and Its Derivatives: A Comprehensive Review

Caffeic acid (CA) and its phenethyl ester (CAPE) are naturally occurring hydroxycinnamic acids with an interesting array of biological activities; e.g., antioxidant, anti-inflammatory, antimicrobial and cytostatic. More recently, several synthetic analogs have also shown similar properties, and some with the advantage of added stability. The actions of these compounds on the cardiovascular system have not been thoroughly explored despite presenting an interesting potential. Indeed the mechanisms underlying the vascular effects of these compounds particularly need clarifying. The aim of this paper is to provide a comprehensive and up-to-date review on current knowledge about CA and its derivatives in the cardiovascular system. Caffeic acid, CAPE and the synthetic caffeic acid phenethyl amide (CAPA) exhibit vasorelaxant activity by acting on the endothelial and vascular smooth muscle cells. Vasorelaxant mechanisms include the increased endothelial NO secretion, modulation of calcium and potassium channels, and modulation of adrenergic receptors. Together with a negative chronotropic effect, vasorelaxant activity contributes to lower blood pressure, as several preclinical studies show. Their antioxidant, anti-inflammatory and anti-angiogenic properties contribute to an important anti-atherosclerotic effect, and protect tissues against ischemia/reperfusion injuries and the cellular dysfunction caused by different physico-chemical agents. There is an obvious shortage of in vivo studies to further explore these compounds' potential in vascular physiology. Nevertheless, their favorable pharmacokinetic profile and overall lack of toxicity make these compounds suitable for clinical studies.

Mechanisms of ranolazine pretreatment in preventing ventricular tachyarrhythmias in diabetic db/db mice with acute regional ischemia-reperfusion injury

Studies have demonstrated that diabetic (db/db) mice have increased susceptibility to myocardial ischemia-reperfusion (IR) injury and ventricular tachyarrhythmias (VA). We aimed to investigate the antiarrhythmic and molecular mechanisms of ranolazine in db/db mouse hearts with acute IR injury. Ranolazine was administered for 1 week before coronary artery ligation. Diabetic db/db and control db/+ mice were divided into ranolazine-given and -nongiven groups. IR model was created by 15-min left coronary artery ligation and 10-min reperfusion. In vivo electrophysiological studies showed that the severity of VA inducibility was higher in db/db mice than control (db/ +) mice. Ranolazine suppressed the VA inducibility and severity. Optical mapping studies in Langendorff-perfused hearts showed that ranolazine significantly shortened action potential duration, Ca_i transient duration, Ca_i decay time, ameliorated conduction inhomogeneity, and suppressed arrhythmogenic alternans induction. Western blotting studies showed that the expression of pThr¹⁷-phospholamban, calsequestrin 2 and voltage-gated sodium channel in the IR zone was significantly downregulated in db/db mice, which was ameliorated with ranolazine pretreatment and might play a role in the anti-arrhythmic actions of ranolazine in db/db mouse hearts with IR injury.

Inhomogeneous downregulation of INa underlies piceatannol proarrhythmic mechanism in regional ischemia-reperfusion

BACKGROUND

Piceatannol, a grape-derived polyphenol, has been linked to proarrhythmic properties by aggravating inhomogeneous conduction delay in the ischemia-reperfusion (IR) zone to enhance arrhythmogenic alternans in heart failure (HF) rabbits. The underlying molecular mechanisms of piceatannol-induced conduction disturbance were unclear in this model.

METHODS

HF was induced by 4 weeks' rapid ventricular pacing. IR injury was induced in vivo using a protocol of left coronary artery ligation and release. Left ventricular cardiomyocytes were isolated enzymatically for whole-cell patch-clamp studies. Piceatannol (10 μM) was administrated to test its inhibitory effect on sodium current (I_Na ). Immunoblots studies and immunoenzymological staining were conducted in tissues sampled from the IR and remote zones.

RESULTS

Peak I_Na density was less in failing cardiomyocytes than control cardiomyocytes. IR injury further reduces peak I_Na density in both groups. Piceatannol showed a greater I_Na inhibitory effect in HF than control cardiomyocytes. Western blots showed reduced Na_V 1.5 protein expression in the HF group compared to the control group but no significant difference between remote and IR zones. Immunostaining showed that IR led to cytosolic redistribution of Na_V 1.5, especially in failing hearts.

CONCLUSIONS

Downregulation of NaV 1.5 protein expression and reduced peak I_Na density are found in the failing hearts. Piceatannol exerts a greater inhibitory effect on peak I_Na in the failing cardiomyocytes than in the controls. IR injury further decreases peak I_Na density, which is more prominent in the failing hearts than in the control hearts.

Chemical characterization and cytotoxic activity evaluation of Lebanese propolis

Chemical composition, anti-proliferative and proapoptotic activity as well as the effect of various fractions of Lebanese propolis on the cell cycle distribution were evaluated on Jurkat leukemic T-cells, glioblastoma U251 cells, and breast adenocarcinoma MDA-MB-231 cells using cytotoxic assays, flow cytometry as well as western blot analysis. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis revealed that ferulic acid, chrysin, pinocembrin, galangin are major constituents of the ethanolic crude extract of the Lebanese propolis, while the hexane fraction mostly contains chrysin, pinocembrin, galangin but at similar levels. Furthermore chemical analysis was performed using gas chromatography-mass spectrometry (GC-MS) to identify major compounds in the hexane fraction. Reduction of cell viability was observed in Jurkat cells exposed to the ethanolic crude extract and the hexane fraction, while viability of U251 and MDA-MB-231 cells was only affected upon exposure to the hexane fraction; the other fractions (aqueous phase, methylene chloride, and ethyl acetate) were without effect. Maximum toxic effect was obtained when Jurkat cells were cultivated with 90μg/ml of both the crude extract and hexane faction. Toxicity started early after 24h of incubation and remained till 72h. Interestingly, the decrease in cell viability was accompanied by a significant increase in p53 protein expression levels and PARP cleavage. Cell cycle distribution showed an increase in the SubG0 fraction in Jurkat, U251 and MDA-MB-231 cells after 24h incubation with the hexane fraction. This increase in SubG0 was further investigated in Jurkat cells by annexinV/PI and showed an increase in the percentage of cells in early and late apoptosis as well as necrosis. In conclusion, Lebanese propolis exhibited significant cytotoxicity and anti-proliferative activity promising enough that warrant further investigations on the molecular targets and mechanisms of action of Lebanese propolis.

In vitro effects of caffeic acid, nortriptyline, precocene I and quercetin against Rhipicephalus annulatus (Acari: Ixodidae)

In the present study, the acaricidal effects of caffeic acid, nortriptyline, precocene I and quercetin against Rhipicephalus annulatus (syn. Boophilus annulatus) Say (Acari: Ixodidae) were evaluated. Adult immersion technique (24 ticks immersed for 2 min in one dilution of the compound) was used for the assessment of the effects of caffeic acid (0.39-100 mg/mL), nortriptyline (0.625-50 mg/L), precocene I (0.004488-5 mg/mL) and quercetin (6.25-100 mg/mL) against R. annulatus. Adult tick mortality, reproductive index, inhibition of fecundity and hatching were calculated. Caffeic acid, nortriptyline, precocene I and quercetin revealed very low adult mortality and inhibition of fecundity, even at the highest concentration tested. Quercetin (>50 mg/mL) caused blocking of hatching of eggs.

Caffeoylquinic Acid Derivatives Extract of Erigeron multiradiatus Alleviated Acute Myocardial Ischemia Reperfusion Injury in Rats through Inhibiting NF-KappaB and JNK Activations

Erigeron multiradiatus (Lindl.) Benth. has been used in Tibet folk medicine to treat various inflammatory diseases. The aim of this study was to investigate antimyocardial ischemia and reperfusion (I/R) injury effect of caffeoylquinic acids derivatives of E. multiradiatus (AE) in vivo and to explain underling mechanism. AE was prepared using the whole plant of E. multiradiatus and contents of 6 caffeoylquinic acids determined through HPLC analysis. Myocardial I/R was induced by left anterior descending coronary artery occlusion for 30 minutes followed by 24 hours of reperfusion in rats. AE administration (10, 20, and 40 mg/kg) inhibited I/R-induced injury as indicated by decreasing myocardial infarct size, reducing of CK and LDH activities, and preventing ST-segment depression in dose-dependent manner. AE decreased cardiac tissue levels of proinflammatory factors TNF-α and IL-6 and attenuated leukocytes infiltration. AE was further demonstrated to significantly inhibit I-κB degradation, nuclear translocation of p-65 and phosphorylation of JNK. Our results suggested that cardioprotective effect of AE could be due to suppressing myocardial inflammatory response and blocking NF-κB and JNK activation pathway. Thus, caffeoylquinic acids might be the active compounds in E. multiradiatus on myocardial ischemia and be a potential natural drug for treating myocardial I/R injury.

Electromechanical and atrial and ventricular antiarrhythmic actions of CIJ-3-2F, a novel benzyl-furoquinoline vasodilator in rat heart

BACKGROUND AND PURPOSE

This study was designed to examine the antiarrhythmic efficacy and the underlying mechanisms of the benzyl-furoquinoline vasodilator, CIJ-3-2F, in rat cardiac preparations.

EXPERIMENTAL APPROACH

Conduction electrograms and left ventricular pressure were determined in Langendorff-perfused hearts. Action potentials were assessed with microelectrode techniques, calcium transients by fura-2 fluorescence and ionic currents by whole-cell patch-clamp techniques.

KEY RESULTS

In isolated hearts, CIJ-3-2F prolonged sinus cycle length, QT interval, Wenckebach cycle length, atrio-His bundle and His bundle-ventricular conduction intervals, refractory periods in atrium, AV node, His-Purkinje system and ventricle, and also increased left ventricular pressure. CIJ-3-2F reduced the incidences of both ischaemic and reperfusion-induced ventricular arrhythmias and prevented the induction of atrial tachyarrhythmias. In both atrial and papillary muscles, CIJ-3-2F decreased upstroke velocity and prolonged duration of the action potential. In ventricular myocytes, CIJ-3-2F moderately increased the amplitude of [Ca(2+)]i transients and cell shortening. CIJ-3-2F inhibited the transient outward K(+) current (Ito ) (IC₅₀ = 4.4 μM) with accelerated inactivation, a slower rate of recovery from inactivation and use-dependency. CIJ-3-2F also suppressed the steady-state outward K(+) current (Iss , IC₅₀ = 3.6 μM, maximum inhibition = 65.7%) and both the inward Na(+) current (INa , IC₅₀ = 2.8 μM) and L-type Ca(2+) current (ICa,L , IC₅₀ = 4.9 μM, maximum inhibition = 69.4%).

CONCLUSIONS AND IMPLICATIONS

CIJ-3-2F blocked Na(+) and Ito channels and, to some extent, also blocked Ca(2+) and Iss channels, modifying cardiac electromechanical function. These effects are likely to underlie its antiarrhythmic properties.

Caffeic acid phenethyl ester, a promising component of propolis with a plethora of biological activities: a review on its anti-inflammatory, neuroprotective, hepatoprotective, and cardioprotective effects

Caffeic acid phenethyl ester (CAPE) is an important active component of honey bee propolis that possesses a plethora of biological activities. Propolis is used safely in traditional medicine as a dietary supplement for its therapeutic benefits. This review highlights the recently published data about CAPE bioavailability, anti-inflammatory, neuroprotective; hepatoprotective and cardioprotective activities. CAPE showed promising efficacy both in vitro and in vivo studies in animal models with minimum adverse effects. Its effectiveness was demonstrated in multiple target organs. Despite this fact, it has not been yet investigated as a protective agent or a potential therapy in humans. Investigation of CAPE efficacy in clinical trials is strongly encouraged to elucidate its therapeutic benefit for different human diseases after performing full preclinical toxicological studies and gaining more insights into its pharmacokinetics.