Caffeic Acid Phenethyl Ester Administration Research Articles

Neuroprotective Effect of Caffeic Acid Phenethyl Ester in A Mouse Model of Alzheimer's Disease Involves Nrf2/HO-1 Pathway.

Alzheimer’s disease (AD) is a progressive pathology, where dementia symptoms gradually worsen over a number of years. The hallmarks of AD, such as amyloid β-peptide (Aβ) in senile plaque and neurofibrillary tangles, are strongly intertwined with oxidative stress, which is considered one of the common effectors of the cascade of degenerative events. The endogenous nuclear factor erythroid 2-related factor 2 (Nrf2) is the "master regulator" of the antioxidant response and it is known as an indicator and regulator of oxidative stress. The present study aimed to determine the potential neuroprotective activity of caffeic acid phenethyl ester (CAPE), a polyphenolic compound abundant in honeybee, against the neurotoxicity of Aβ1-42 oligomers (AβO) in mice. An intracerebroventricular (i.c.v.) injection of AβO into the mouse brain triggered increased reactive oxygen species levels, neurodegeneration, neuroinflammation, and memory impairment. In contrast, the intraperitoneal administration of CAPE (10 mg/kg) after i.c.v. AβO-injection counteracted oxidative stress accompanied by an induction of Nrf2 and heme oxygenase-1 via the modulation of glycogen synthase kinase 3β in the hippocampus of mice. Additionally, CAPE treatment decreased AβO-induced neuronal apoptosis and neuroinflammation, and improved learning and memory, protecting mice against the decline in spatial cognition. Our findings demonstrate that CAPE could potentially be considered as a promising neuroprotective agent against progressive neurodegenerative diseases such as AD.

Caffeic acid phenethyl ester ameliorates pulmonary inflammation and apoptosis reducing Nf-κβ activation in blunt pulmonary contusion model.

Pulmonary contusion (PC) is an important life-threatening clinical condition characterized by lung injury and inflammation. Caffeic acid phenethyl ester (CAPE) is a biological agent with potent antioxidant and anti-inflammatory effects. This study aimed to investigate the potential effects of CAPE on tissue damage, nuclear factor kappa-beta (Nf-κβ) activity, inducible nitric oxide synthase (iNOS) synthesis, and pulmonary apoptosis in an experimental PC model. Forty adult Wistar albino rats were used in this study and divided into four groups as follows: control, PC, PC + CAPE, and CAPE. CAPE was administered intraperitoneally for seven days following PC formation (10 µmol/kg, dissolved in dimethyl sulfoxide). Wet/dry weight ratio in lung tissue was determined. The pulmonary tissue was examined using hematoxylin-eosin and Masson's trichrome histochemical staining and also by scanning electron microscopy. Nf-κβ and iNOS activities in the lungs were determined by the indirect immunohistochemical method. Pulmonary apoptosis was detected by the TUNEL method. Increased leukocyte infiltration score, pulmonary edema, alveolar damage, and increased Nf-κβ and iNOS activities were determined in the PC group. CAPE administration inhibited Nf-κβ and iNOS activities and pulmonary apoptosis. In this study, the findings showed that CAPE inhibited tissue damage by suppressing inflammatory mediators of Nf-κβ and iNOS activities. Also, CAPE was found to be protective in the lung tissue and could be used as a therapeutic agent.

Caffeic acid phenethyl ester promotes haematopoietic stem/progenitor cell homing and engraftment

BackgroundSeveral studies have suggested that caffeic acid phenethyl ester (CAPE) can induce the expression of hypoxia inducible factor-1α (HIF-1α) protein. We determined whether CAPE has a novel function in improving the homing and engraftment of haematopoietic stem/progenitor cells (HSPCs) by regulating HIF-1α gene expression in the bone marrow (BM) niche.MethodsFor survival experiments, lethally irradiated C57BL/6 mice were injected with a low number of BM mononuclear cells (MNCs) and CAPE according to the indicated schedule. Homing efficiency analysis was conducted using flow cytometry and colony-forming unit (CFU) assays. The influence of intraperitoneal injection of CAPE on short-term and long-term engraftment of HSPCs was evaluated using competitive and non-competitive mouse transplantation models. To investigate the mechanism by which CAPE enhanced HSPC homing, we performed these experiments including Q-PCR, western blot, immunohistochemistry and CFU assays after in-vivo HIF-1α activity blockade.ResultsCAPE injection significantly increased the survival rate of recipient mice after lethal irradiation and transplantation of a low number of BM MNCs. Using HSPC homing assays, we found that CAPE notably increased donor HSPC homing to recipient BM. The subsequent short-term and long-term engraftment of transplanted HSPCs was also improved by the optimal schedule of CAPE administration. Mechanistically, we found that CAPE upregulated the expression of HIF-1α, vascular endothelial growth factor-A (VEGF-A) and stromal cell-derived factor 1α (SDF-1α). The HIF-1α inhibitor PX-478 blocked CAPE-enhanced HSPC homing, which supported the idea that HIF-1α is a key target of CAPE.ConclusionsOur results showed that CAPE administration facilitated HSPC homing and engraftment, and this effect was primarily dependent on HIF-1α activation and upregulation of SDF-1α and VEGF-A expression in the BM niche.

Caffeic acid phenethyl ester is protective in experimental ulcerative colitis via reduction in levels of pro-inflammatory mediators and enhancement of epithelial barrier function

BackgroundInhibition of the nuclear factor kappa beta (NF-κβ) pathway has been proposed as a therapeutic target due to its key role in the expression of pro-inflammatory genes, including pro-inflammatory cytokines, chemokines, and adhesion molecules. Caffeic acid phenethyl ester (CAPE) is a naturally occurring anti-inflammatory agent, found in propolis, and has been reported as a specific inhibitor of NF-κβ. However, the impact of CAPE on levels of myeloperoxidases (MPO) and pro-inflammatory cytokines during inflammation is not clear. The aims of this study were to investigate the protective efficacy of CAPE in the mouse model of colitis and determine its effect on MPO activity, pro-inflammatory cytokines levels, and intestinal permeability.MethodDextran sulphate sodium was administered in drinking water to induce colitis in C57/BL6 mice before treatment with intraperitoneal administration of CAPE (30 mg kg−1 day−1). Disease activity index (DAI) score, colon length and tissue histology levels of MPO, pro-inflammatory cytokines, and intestinal permeability were observed.ResultsCAPE-treated mice had lower DAI and tissue inflammation scores, with improved epithelial barrier protection and significant reduction in the level of MPO and pro-inflammatory cytokines.ConclusionOur results show that CAPE is effective in suppressing inflammation-triggered MPO activity and pro-inflammatory cytokines production while enhancing epithelial barrier function in experimental colitis. Thus, we conclude that CAPE could be a potential therapeutic agent for further clinical investigations for treatment of inflammatory bowel diseases in humans.

Binding of small molecule to ASC leads to the suppression of NLRP3 inflammasome and acute gout symptoms

Abstract The NOD-like receptor family, pyrin domain containing 3 (NLRP3) inflammasome, which is composed of NLRP3, the adaptor protein ASC, and caspase-1, is closely linked to the pathogenesis of metabolic diseases. We investigated whether caffeic acid phenethyl ester (CAPE), an anti-inflammatory phytochemical, could modulate the activation of NLRP3 inflammasome and have beneficial effects on the related disease such as acute gout. In primary mouse macrophages, CAPE blocked NLRP3 inflammasome activation induced by monosodium uric acid (MSU) crystals. In a mouse air pouch inflammation model and an acute gout model, oral administration of CAPE suppressed MSU-induced caspase-1 activation and interleukin (IL)-1b production, correlating with the attenuation of inflammatory symptoms. CAPE inhibited inflammasome activation induced by ASC, but not NLRP3 nor caspase-1. CAPE directly associated with ASC, resulting in the blockade of NLRP3-ASC interaction. These results demonstrate a novel inhibitory mechanism by which small molecules regulate NLRP3 inflammasome targeting ASC, suggesting the therapeutic strategy for NLRP3-related inflammatory diseases.

Targeting ASC in NLRP3 inflammasome by caffeic acid phenethyl ester: a novel strategy to treat acute gout.

Gouty arthritis is caused by the deposition of uric acid crystals, which induce the activation of NOD-like receptor family, pyrin domain containing 3(NLRP3) inflammasome. The NLRP3 inflammasome, composed of NLRP3, the adaptor protein ASC, and caspase-1, is closely linked to the pathogenesis of various metabolic diseases including gouty arthritis. We investigated whether an orally administrable inhibitor of NLRP3 inflammasome was effective for alleviating the pathological symptoms of gouty arthritis and what was the underlying mechanism. In primary mouse macrophages, caffeic acid phenethyl ester(CAPE) blocked caspase-1 activation and IL-1β production induced by MSU crystals, showing that CAPE suppresses NLRP3 inflammasome activation. In mouse gouty arthritis models, oral administration of CAPE suppressed MSU crystals-induced caspase-1 activation and IL-1β production in the air pouch exudates and the foot tissues, correlating with attenuation of inflammatory symptoms. CAPE directly associated with ASC as shown by SPR analysis and co-precipitation, resulting in blockade of NLRP3-ASC interaction induced by MSU crystals. Our findings provide a novel regulatory mechanism by which small molecules harness the activation of NLRP3 inflammasome by presenting ASC as a new target. Furthermore, the results suggest the preventive or therapeutic strategy for NLRP3-related inflammatory diseases such as gouty arthritis using orally available small molecules.

The effects of caffeic acid phenethyl ester on streptozotocin-induced diabetic liver injury.

The aim of the present study was to clarify the role of oxidative stress in streptozotocin induced liver injury and the possible protective effect of caffeic acid phenethyl ester (CAPE) using histological and biochemical parameters. 32 male Wistar rats were divided into 4 groups as follows: Group 1: Control animals, Group 2: Control animals given CAPE Group 3: STZ-induced diabetic animals (DM group), Group 4: STZ-induced diabetic rats given CAPE (DM+CAPE group). All the injections started on the same day of single-dose STZ injection and continued for 20 days. At the end of this period, livers were removed and processed for routine histological procedures. Biochemical parameters and morphological changes were examined. In DM group, blood glucose levels were significantly increased compared with the control group. Significant increases in tissue malondialdehyde (MDA) level and decreases in superoxide dismutase (SOD) and total glutathione (GSH) activities were detected in DM group. Administration of CAPE significantly reduced these values. STZ-induced histopathological alterations including inflammatory cell infiltration around portal triad, congestion, loss of glycogen in the hepatocytes. Additionally, degenerative cellular alterations, such as numerous vacuolizations including myelinic figure formation, pyknotic nuclei with peripheral localization of heterochromatin condensation and mitochondrial elongation were observed in cytoplasm of hepatocytes. CAPE significantly reduced these histopathological changes. Our results indicate that CAPE should be considered in the prevention of oxidative stress in diabetic liver.

The effects of pentoxifylline and caffeic acid phenethyl ester in the treatment of d-galactosamine-induced acute hepatitis in rats.

The aim of this study was to investigate histological changes in hepatic tissue and effects of pentoxifylline (PTX) and caffeic acid phenethyl ester (CAPE) on these changes using histochemical and biochemical methods in rats, in which hepatitis was established by D-galactosamine (D-GAL). Rats were divided into five groups as follows: control group, D-GAL (24 h) group, D-GAL group, d-GAL + PTX group, and D-GAL + CAPE group. In histological evaluations, the control group showed normal appearance of the liver cells. However in the d-GAL groups, focal areas consisting of inflammatory, necrotic, and apoptotic cells were detected in parenchyma. Glycogen loss was observed in the hepatocytes localized at the periphery of lobule. It was found that number of mast cells of portal areas were significantly higher in D-GAL groups compared with other groups (p = 0.0001). In addition, the number of cells with positive staining by Ki-67 and caspase-3 were significantly increased in GAL groups compared with the control group (p = 0.0001). In biochemical analysis, there was an increase in malondialdehyde and myeloperoxidase levels, while a decrease was observed in glutathione level and glutathione peroxidase activity in groups treated with d-GAL compared with the control group. On the other hand, it was seen that, in the groups treated with D-GAL, histological and biochemical injuries in the liver were reduced by administration of PTX and CAPE. In this study, we demonstrated the ameliorative effects of PTX and CAPE on D-GAL-induced liver injury.

Regulatory effects of caffeic acid phenethyl ester on neuroinflammation in microglial cells.

Microglial activation has been widely demonstrated to mediate inflammatory processes that are crucial in several neurodegenerative disorders. Pharmaceuticals that can deliver direct inhibitory effects on microglia are therefore considered as a potential strategy to counter balance neurodegenerative progression. Caffeic acid phenethyl ester (CAPE), a natural phenol in honeybee propolis, is known to possess antioxidant, anti-inflammatory and anti-microbial properties. Accordingly, the current study intended to probe the effects of CAPE on microglia activation by using in vitro and in vivo models. Western blot and Griess reaction assay revealed CAPE significantly inhibited the expressions of inducible nitric oxide synthase (NOS), cyclooxygenase (COX)-2 and the production of nitric oxide (NO). Administration of CAPE resulted in increased expressions of hemeoxygenase (HO)-1and erythropoietin (EPO) in microglia. The phosphorylated adenosine monophosphate-activated protein kinase (AMPK)-α was further found to regulate the anti-inflammatory effects of caffeic acid. In vivo results from immunohistochemistry along with rotarod test also revealed the anti-neuroinflammatory effects of CAPE in microglia activation. The current study has evidenced several possible molecular determinants, AMPKα, EPO, and HO-1, in mediating anti-neuroinflammatory responses in microglial cells.

Caffeic acid phenethyl ester inhibits liver fibrosis in rats.

To investigate the hepatoprotective effects and antioxidant activity of caffeic acid phenethyl ester (CAPE) in rats with liver fibrosis. A total of 75 male Sprague-Dawley rats were randomly assigned to seven experimental groups: a normal group (n = 10), a vehicle group (n = 10), a model group (n = 15), a vitamin E group (n = 10), and three CAPE groups (CAPE 3, 6 and 12 mg/kg, n = 10, respectively). Liver fibrosis was induced in rats by injecting CCl4 subcutaneously, feeding with high fat forage, and administering 30% alcohol orally for 10 wk. Concurrently, CAPE (3, 6 and 12 mg/kg) was intraperitoneally administered daily for 10 wk. After that, serum total bilirubin (TBil), aminotransferase (ALT) and aspartate aminotransferase (AST) levels were measured to assess hepatotoxicity. To investigate antioxidant activity of CAPE, malondialdehyde (MDA), glutathione (GSH) levels, catalase (CAT) and superoxide dismutase (SOD) activities in liver tissue were determined. Moreover, the effect of CAPE on α-smooth muscle actin (α-SMA), a characteristic hallmark of activated hepatic stellate cells (HSCs), and NF-E2-related factor 2 (Nrf2), a key transcription factor for antioxidant systems, was investigated by immunohistochemistry. Compared to the model group, intraperitoneal administration of CAPE decreased TBil, ALT, and AST levels in liver fibrosis rats (P < 0.05), while serum TBil was decreased by CAPE in a dose-dependent manner. In addition, the liver hydroxyproline contents in both the 6 and 12 mg/kg CAPE groups were markedly lower than that in the model group (P < 0.05 and P < 0.001, respectively). CAPE markedly decreased MDA levels and, in turn, increased GSH levels, as well as CAT and SOD activities in liver fibrosis rats compared to the model group (P < 0.05). Moreover, CAPE effectively inhibited α-SMA expression while increasing Nrf2 expression compared to the model group (P < 0.01). The protective effects of CAPE against liver fibrosis may be due to its ability to suppress the activation of HSCs by inhibiting oxidative stress.

Caffeic acid phenethyl ester protects against amphotericin B induced nephrotoxicity in rat model.

The present study was conducted to investigate whether caffeic acid phenethyl ester (CAPE), an active component of propolis extract, has a protective effect on amphotericin B induced nephrotoxicity in rat models. Male Wistar-Albino rats were randomly divided into four groups: (I) control group (n = 10), (II) CAPE group (n = 9) which received 10 μmol/kg CAPE intraperitoneally (i.p.), (III) amphotericin B group (n = 7) which received one dose of 50 mg/kg amphotericin B, and (IV) amphotericin B plus CAPE group (n = 7) which received 10 μmol/kg CAPE i.p. and one dose of 50 mg/kg amphotericin B. The left kidney was evaluated histopathologically for nephrotoxicity. Levels of malondialdehyde (MDA), nitric oxide (NO), enzyme activities including catalase (CAT), and superoxide dismutase (SOD) were measured in the right kidney. Histopathological damage was prominent in the amphotericin B group compared to controls, and the severity of damage was lowered by CAPE administration. The activity of SOD, MDA, and NO levels increased and catalase activity decreased in the amphotericin B group compared to the control group (P = 0.0001, P = 0.003, P = 0.0001, and P = 0.0001, resp.). Amphotericin B plus CAPE treatment caused a significant decrease in MDA, NO levels, and SOD activity (P = 0.04, P = 0.02, and P = 0.0001, resp.) and caused an increase in CAT activity compared with amphotericin B treatment alone (P = 0.005). CAPE treatment seems to be an effective adjuvant agent for the prevention of amphotericin B nephrotoxicity in rat models.

Novel antidepressant-like activity of caffeic Acid phenethyl ester is mediated by enhanced glucocorticoid receptor function in the hippocampus.

Caffeic acid phenethyl ester (CAPE) is an active component of propolis that has a variety of potential pharmacological effects. Although we previously demonstrated that propolis has antidepressant-like activity, the effect of CAPE on this activity remains unknown. The present study assessed whether treatment with CAPE (5, 10, and 20 µmol/kg for 21 days) has an antidepressant-like effect in mice subjected to chronic unpredictable stress via tail suspension (TST) and forced swim (FST) tests. CAPE administration induced behaviors consistent with an antidepressant effect, evidenced by decreased immobility in the TST and FST independent of any effect on serum corticosterone secretion. Western blots, conducted subsequent to behavioral assessment, revealed that CAPE significantly decreased glucocorticoid receptor phosphorylation at S234 (pGR(S234)), resulting in an increased pGR(S220/S234) ratio. We also observed negative correlations between pGR(S220)/(S234) and p38 mitogen-activated protein kinase (p38MAPK) phosphorylation, which was decreased by CAPE treatment. These findings suggest that CAPE treatment exerts an antidepressant-like effect via downregulation of p38MAPK phosphorylation, thereby contributing to enhanced GR function.

Protective role of caffeic acid phenethyl ester on serum cholinesterase inhibition by acute exposure to diazinon in rats.

To evaluate whether caffeic acid phenethyl ester (CAPE), a flavonoid-like natural compound plentifully found in beeswax, has a protective effect on diazinon-induced serum cholinesterase (ChE) inhibition in rats. Animals were divided into 4 groups. The first animal group was not treated with any substance. The second animal group was orally given a 200 mg/kg body weight (bw) sublethal dose of diazinon. The third animal group was injected intraperitoneally with 2.84 mg (10 micromol)/kg bw of CAPE 1 day prior to administration of 200 mg/kg bw of diazinon orally. The fourth animal group was intraperitoneally injected with 2.84 mg (10 tmol)/kg bw of CAPE 30 min after 200 mg/kg bw of diazinon was orally administered. Analysis of the animal blood samples obtained 48 h after diazinon administration revealed that diazinon decreased serum ChE activity by 75%, while CAPE administration 24 h prior to and 30 min following diazinon application improved serum ChE activity by 25%-32% as compared to levels with diazinon administration only. In silico studies suggest that CAPE prevents diazinon from binding to butyryl ChE due to a higher binding affinity than that of diazinon. Our laboratory findings suggest that CAPE plays a protective role against butyryl ChE inhibition by diazinon.

Enhanced antioxidant effect of caffeic acid phenethyl ester and Trolox in combination against radiation induced-oxidative stress

Combinations of antioxidants are believed to be more effective than single antioxidant because when antioxidants are combined they support each other synergistically to create a magnified effect. Discovering the enhancer effects or synergies between bioactive components is valuable for resisting oxidative stress and improving health benefits. The aim of this study was to investigate a possible cooperation of natural antioxidant caffeic acid phenethyl ester (CAPE) with synthetic antioxidant Trolox in the model systems of chemical generation of free radicals, lipid peroxidation of microsomes and radiation-induced oxidative injury in L929 cells. Based on the intermolecular interaction between CAPE and Trolox, the present study shows a synergistic effect of CAPE and Trolox in combination on elimination of three different free radicals and inhibition of lipid peroxidation initiated by three different systems. CAPE and Trolox added simultaneously to the L929 cells exerted an enhanced preventive effect on the oxidative injury induced by radiation through decreasing ROS generation, protecting plasma membrane and increasing the ratios of reduced glutathione/oxidized glutathione and the expression of key antioxidant enzymes mediated by nuclear factor erythroid 2 p45-related factor 2 (Nrf2). Our results showed for the first time that administration of CAPE and Trolox in combination may exert synergistic antioxidant effects, and further indicate that CAPE and Trolox combination functions mainly through scavenging ROS directly, inhibiting lipid peroxidation and promoting redox cycle of GSH mediated by Nrf2-regulated glutathione peroxidase and glutathione reductase expression.

Impact of caffeic acid phenethyl ester treatment on vancomycin-induced pancreatic damage in rats

This study investigates the preventive effect of caffeic acid phenethyl ester (CAPE) on pancreatic damage induced by vancomycin (VCM) in rats. Rats were equally divided into three groups: group I (control), group II (only VCM-treated group) and group III (VCM + CAPE-treated groups). VCM was intraperitoneally administered at a dose of 200 mg kg(-1)twice daily for 7 days. CAPE was administered orally at 10 µM mL(-1) kg(-1) dose once daily for 7 days. The first dose of CAPE administration was performed 24 h prior to VCM injection. Blood and pancreas tissue samples were removed and collected after the study. Serum alkaline phosphatase (ALP), amylase, γ-glutamyl transferase (GGT) and lipase activities were determined. Pancreas tissue samples were evaluated with the light microscope. Group II significantly increased serum ALP, amylase, GGT and lipase activities when compared with the control group. Group III significantly decreased serum ALP, amylase, GGT and lipase activities when compared with group II. In histopathological examination, it has been observed that there was a significant pancreatic damage in group II. CAPE exerted prominent structural protection against VCM-induced pancreatic damage and this effect was statistically significant. CAPE caused a marked reduction in the extent of pancreatic damage. We have concluded that it may play an important role in the VCM-induced pancreatic damage and reduce the pancreatic damage both at the biochemical and histopathological aspects.

Protective effects of caffeic acid phenethyl ester on ifosfamide-induced central neurotoxicity in rats

The aim of this study was to establish the protective effect of caffeic acid phenethyl ester (CAPE) against the ifosfamide (IFOS)-induced central neurotoxicity in rats and to determine the changes in oxidant-antioxidant status of brain tissue. A total of 35 Wistar rats (aged 7-12 days) were used in the experiments. The study comprised of five groups. Control untreated rats (n = 7) belonged to group 1; group 2 was given intraperitoneal (IP) injection of CAPE alone (10 µmol/kg; n = 7); group 3 was treated with single IP injection of IFOS (500 mg/kg; n = 7); group 4 was treated for 2 days with IP administration of CAPE (10 µmol/kg) beginning from one day before single IP injection of IFOS (n = 7); and group 5 was treated with saline and 10% ethanol. At the 24th hour of IFOS treatment, brain tissues were removed for analysis. The brain catalase activity was lower in IFOS group than the other groups (p < 0.05). The levels of malondialdehyde (MDA) and protein carbonyl content in brain tissue were higher in IFOS group than the control, CAPE, ethanol, and IFOS + CAPE groups (p < 0.05). There was no significant difference between MDA and protein carbonyl content of control, CAPE, ethanol, and IFOS + CAPE groups. Immunohistochemistry showed marked activation of caspase 3 in the IFOS group at 24 h after treatment. This study revealed that pretreatment with CAPE might protect brain tissue against IFOS-induced central neurotoxicity. CAPE could be an effective course of therapy to enhance therapeutic efficacy and to lessen IFOS toxicity in clinical chemotherapy.

Caffeic acid phenethyl ester (CAPE) protects against acute urogenital injury following pneumoperitoneum in the rat

Purpose: Our aim is to determine the biochemical and histologic changes induced in the kidneys, testis and prostate on possible ischemia and reperfusion (I/R) injury caused by pneumoperitoneum (PNP) in a rat model and to evaluate the ability of protective effects of caffeic acid phenethyl ester (CAPE). Methods: Twenty-eight adult male Wistar albino rats were randomly divided to one of three treatment groups, with seven animals in each group. Sham, laparoscopy (L), and laparoscopy plus CAPE (L + C) group were subjected to 60 min of PNP with 15 mmHg one hour before the desufflation period. Total oxidant status (TOS) and total antioxidant status (TAS) levels were determined in kidney, testis, and prostate. Kidney and testis tissues were removed to obtain a histologic score. Also, Johnsen scoring system was used for testicular tissue analysis. Results: L group had significantly higher TOS and lower TAS levels on kidney and testis compared to the other groups. In prostate biochemical analysis, there was not any difference between groups. No difference was found between groups according to kidney and testis tissues’ histologic evaluation. In evaluation of Johnsen scoring, L group showed significant lower score compared to the other two groups. Conclusions: Increased intraabdominal pressure (IAP) had an oxidative effect on kidney and testis but not on prostate in rats. Moreover, it could affect the testicular Johnsen score. All these adverse effects of IAP on both kidney and testis could be prevented by CAPE administration.

Caffeic acid phenethyl ester prevents apoptotic cell death in the developing rat brain after pentylenetetrazole-induced status epilepticus

Population-based studies suggest that seizure incidence is highest during the first year of life, and early-life seizures frequently result in the development of epilepsy and behavioral alterations later in life. The early-life insults like status epilepticus often lead to epileptogenesis, a process in which initial brain injury triggers cascades of molecular, cellular, and network changes and eventually spontaneous seizures. Caffeic acid phenethyl ester is an active component of propolis obtained from honeybees and has neuroprotective properties. The aim of this study was to investigate whether caffeic acid phenethyl ester exerts neuroprotective effects on the developing rat brain after status epilepticus. Twenty-one dams reared Wistar male rats, and 21-day-old rats were divided into three groups: control group, pentylenetetrazole-induced status epilepticus group, and caffeic acid phenethyl ester-treated group. Status epilepticus was induced on the first day of experiment. Caffeic acid phenethyl ester injections (30mg/kg intraperitoneally) started 40min after the tonic phase of status epilepticus was reached, and the injections of caffeic acid phenethyl ester were repeated over 5days. Rats were sacrificed, and brain tissues were collected on the 5th day of experiment after the last injection of caffeic acid phenethyl ester. Apoptotic cell death was evaluated. Histopathological examination showed that caffeic acid phenethyl ester significantly preserved the number of neurons in the CA1, CA3, and dentate gyrus regions of the hippocampus and the prefrontal cortex. It also diminished apoptosis in the hippocampus and the prefrontal cortex. In conclusion, this experimental study suggests that caffeic acid phenethyl ester administration may be neuroprotective in status epilepticus in the developing rat brain.

Caffeic acid phenethyl ester activation of Nrf2 pathway is enhanced under oxidative state: Structural analysis and potential as a pathologically targeted therapeutic agent in treatment of colonic inflammation

Caffeic acid phenethyl ester (CAPE) is a polyphenolic natural product that possesses numerous biological activities including anti-inflammatory effects. CAPE-mediated nuclear factor-erythroid 2 p45 (NF-E2)-related factor 2 (Nrf2) activation is likely responsible for some of its biological effects. CAPE was chemically modified to yield CAPE analogues that were subjected to experiments examining cellular Nrf2 activity. CAPE and the CAPE analogue with a catechol moiety, but not the other analogues, activated the Nrf2 pathway. In addition, only biotin-labeled CAPE analogues with the catechol moiety precipitated Kelch-like ECH associated protein 1 (Keap1) when incubated with cell lysates and streptavidin agarose beads. Sodium hypochlorite (NaOCl) oxidation of the catechol moiety in CAPE produced an oxidized, electrophilic form of CAPE (Oxi-CAPE) and greatly enhanced the ability of CAPE to activate Nrf2 and to bind to Keap1. Rectal administration of CAPE ameliorated 2,4,6-trinitrobenzene sulfonic acid-induced rat colitis and activated the Nrf2 pathway in the inflamed colon, and incubation of CAPE in the lumen of the inflamed distal colon generated Oxi-CAPE. However, these biological effects and chemical change of CAPE were not observed in the normal colon. Our data suggest that CAPE requires the catechol moiety for the oxidation-enhanced activation of the Nrf2 pathway and has potential as a pathologically targeted Nrf2-activating agent that is exclusively activated in pathological states with oxidative stress such as colonic inflammation.

Caffeic Acid Phenethyl Ester Suppresses Proliferation and Survival of TW2.6 Human Oral Cancer Cells via Inhibition of Akt Signaling

Caffeic acid phenethyl ester (CAPE) is a bioactive component extracted from honeybee hive propolis. Our observations indicated that CAPE treatment suppressed cell proliferation and colony formation of TW2.6 human oral squamous cell carcinoma (OSCC) cells dose-dependently. CAPE treatment decreased G1 phase cell population, increased G2/M phase cell population, and induced apoptosis in TW2.6 cells. Treatment with CAPE decreased protein abundance of Akt, Akt1, Akt2, Akt3, phospho-Akt Ser473, phospho-Akt Thr 308, GSK3β, FOXO1, FOXO3a, phospho-FOXO1 Thr24, phospho-FoxO3a Thr32, NF-κB, phospho-NF-κB Ser536, Rb, phospho-Rb Ser807/811, Skp2, and cyclin D1, but increased cell cycle inhibitor p27Kip. Overexpression of Akt1 or Akt2 in TW2.6 cells rescued growth inhibition caused by CAPE treatment. Co-treating TW2.6 cells with CAPE and 5-fluorouracil, a commonly used chemotherapeutic drug for oral cancers, exhibited additive cell proliferation inhibition. Our study suggested that administration of CAPE is a potential adjuvant therapy for patients with OSCC oral cancer.