Caffeic acid phenethyl ester

Caffeic acid phenethyl ester (CAPE) is an inhibitor of NF-κB activation [1].

CAPE derives from honeybee propolis and has several biological activities. It is found to be an inhibitor of NF-κB activation. In U937 cells, CAPE inhibits the TNF-dependent activation of NF-κB dose-dependently. The maximum effect occurs at dose of 25μg/ml. CAPE also inhibits NF-κB activation induced by phorbol ester, ceramide, okadaic acid and hydrogen peroxide. It is reported that CAPE prevents NF-κB from binding to DNA without affecting other transcription factors. CAPE also has angiogenesis efficacy. It shows inhibition effect on the formation of capillary-like tubes. Besides, it reduces the production of VEGF both in CT26 cell culture and in animal model. In addition, CAPE effectively prevents CT26 cells from secreting MMP-2 and MMP-9 [1, 2].

References:
[1] Natarajan K, Singh S, Burke TR Jr, Grunberger D, Aggarwal BB. Caffeic acid phenethyl ester is a potent and specific inhibitor of activation of nuclear transcription factor NF-kappa B. Proc Natl Acad Sci U S A. 1996 Aug 20;93(17):9090-5.
[2] Liao HF, Chen YY, Liu JJ, Hsu ML, Shieh HJ, Liao HJ, Shieh CJ, Shiao MS, Chen YJ. Inhibitory effect of caffeic acid phenethyl ester on angiogenesis, tumor invasion, and metastasis. J Agric Food Chem. 2003 Dec 31;51(27):7907-12.

Caffeic acid phenethyl ester inhibits the inflammatory effects of interleukin-1beta in human corneal fibroblasts.[Pubmed:25151996]

Immunopharmacol Immunotoxicol. 2014 Oct;36(5):371-7.

CONTEXT: Expression of various inflammatory mediators in corneal fibroblasts contributes to corneal inflammation. OBJECTIVE: The purpose of this study was to assess the possible effects of Caffeic acid phenethyl ester (CAPE) on the expression of inflammatory mediators during an inflammatory response in human corneal fibroblasts. MATERIALS AND METHODS: The levels of interleukin (IL)-6, monocyte chemotactic protein (MCP)-1, and intercellular adhesion molecule-1 (ICAM-1) from IL-1beta-exposed human corneal fibroblasts were measured with enzyme-linked immunosorbent assays (ELISA). The regulatory mechanisms of CAPE on cellular signaling pathways were examined using Western blot and electrophoretic mobility shift assays. A functional validation was carried out by evaluating the inhibitory effects of CAPE on neutrophil and monocyte migration in vitro. RESULTS: CAPE inhibited the expression of IL-6, MCP-1 and ICAM-1 induced by the pro-inflammatory cytokine IL-1beta in corneal fibroblasts. The activation of AKT and NF-kappaB by IL-1beta was markedly inhibited by CAPE, whereas the activity of mitogen-activated protein kinases (MAPKs) was not affected. CAPE significantly suppressed the IL-1beta-induced migration of differentiated (d)HL-60 and THP-1 cells. DISCUSSION: These anti-inflammatory effects of CAPE may be expected to inhibit the infiltration of leukocytes into the corneal stroma in vivo.

Protective effects of caffeic acid phenethyl ester (CAPE) against neomycin-induced hair cell damage in zebrafish.[Pubmed:24880922]

Int J Pediatr Otorhinolaryngol. 2014 Aug;78(8):1311-5.

OBJECTIVE: Caffeic acid phenethyl ester (CAPE) is known to reduce the generation of oxygen-derived free radicals, which is a major mechanism of aminoglycoside-induced ototoxicity. The objective of the present study was to evaluate the effects of CAPE on neomycin-induced ototoxicity in zebrafish (Brn3c: EGFP). METHODS: Five-day post-fertilization zebrafish larvae (n=10) were exposed to 125 muM neomycin and one of the following CAPE concentrations for 1h: 50, 100, 250, 500, or 1000 muM. Ultrastructural changes were evaluated using scanning electron microscopy (SEM). The terminal deoxynucleotidyl transferase (TdT)-mediated dUTP-biotin nick-end labeling (TUNEL) assay and 2-[4-(dimethylamino)styryl]-N-ethylpyridiniumiodide (DASPEI) assay were performed for evaluation of apoptosis and mitochondrial damage. RESULTS: CAPE decreased neomycin-induced hair cell loss in the neuromasts (500 muM CAPE: 12.7 +/- 1.1 cells, 125 muM neomycin only: 6.3 +/- 1.1 cells; n = 10, P < 0.05). In the ultrastructural analysis, structures of mitochondria and hair cells were preserved when exposed to 125 muM neomycin and 500 muM CAPE. CAPE decreased apoptosis and mitochondrial damage. CONCLUSION: In the present study, CAPE attenuated neomycin-induced hair cell damage in zebrafish. The results of the current study suggest that neomycin induces apoptosis, and the apoptotic cell death can be prevented by treatment with CAPE in zebrafish.

Caffeic acid phenethyl ester prevents apoptotic cell death in the developing rat brain after pentylenetetrazole-induced status epilepticus.[Pubmed:24012504]

Epilepsy Behav. 2013 Nov;29(2):275-80.

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 (30 mg/kg intraperitoneally) started 40 min after the tonic phase of status epilepticus was reached, and the injections of Caffeic acid phenethyl ester were repeated over 5 days. 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.

Effects of caffeic acid phenethyl ester on wound healing of nasal mucosa in the rat: an experimental study.[Pubmed:24767474]

Am J Otolaryngol. 2014 Jul-Aug;35(4):482-6.

PURPOSE: Wound healing of the nasal mucosa is a highly complex process that restores the anatomical and functional integrity of tissue that has been exposed to trauma. In this experimental study, our aim was to use histopathological examination to investigate the effects of Caffeic acid phenethyl ester on the wound healing of rat nasal mucosa after mechanical trauma. MATERIALS AND METHODS: The rats were randomly divided into 3 experimental groups: a non-treated group (n=7), a control saline group (n=7) and a Caffeic acid phenethyl ester group (n=7). The non-treated group received no treatment for 15 days. The second group was administered saline (2.5 mL/kg, intraperitoneal) once a day for 15 days. The third group received Caffeic acid phenethyl ester intraperitoneally at a dose of 10 mumol/kg once a day for 15 days. At the beginning of the study, unilateral mechanical nasal trauma was induced on the right nasal mucosa of all rats in the three groups using a brushing technique. Samples were stained using hematoxylin and eosin solution and were examined by a pathologist using a light microscope. RESULTS: The severity of inflammation was milder in the Caffeic acid phenethyl ester group compared with that in the non-treated and saline groups (P<0.05). The subepithelial thickness index was lower in the experimental group (P<0.05). Goblet cell and ciliated cell loss was substantially reduced in the experimental group compared with the non-treated and saline groups (P<0.05). CONCLUSIONS: Caffeic acid phenethyl ester decreases inflammation and the loss of goblet cells and ciliated cells. Therefore, Caffeic acid phenethyl ester has potential beneficial effects on the wound healing of nasal mucosa in the rat.

Effect of caffeic acid phenethyl ester on myringosclerosis development in the tympanic membrane of rat.[Pubmed:24281567]

Eur Arch Otorhinolaryngol. 2015 Jan;272(1):29-34.

Myringosclerosis is hyalinization and calcification of certain areas of the tympanic membrane, especially the fibrous lamina propria layer and appears as white sclerotic lesions. Ventilation tube insertion is one of the most performed operations in the pediatric otorhinolaryngology practice to treat chronic otitis media with effusion. Myringosclerosis is a very common sequela of ventilation tube insertion. In this experimental study, our aim was to show the histopathological effects of Caffeic acid phenethyl ester on myringosclerosis development in rat tympanic membrane after myringotomy. The rats were randomly categorized into four experimental groups including the comparison group (n = 4), non-treated group (n = 7), the saline (control) group (n = 7), the Caffeic acid phenethyl ester group (n = 7). Non-treated group did not receive any treatment for 15 days. Saline (2.5 mL/kg, intraperitoneal) was administered to the third group once a day for 15 days. Fourth group received Caffeic acid phenethyl ester intraperitoneally once a day at a dose of 10 mumol/kg for 15 days. Myringotomy was performed on the right tympanic membrane of all rats except comparison group using a sterile pick with the help of an operating microscope. Histopathological examination of myringosclerosis formation was done by a pathologist under light microscope. In histopathological analysis of groups, the severity of inflammation was milder in Caffeic acid phenethyl ester group compared to non-treated and saline groups (p < 0.05). There was less myringosclerotic plaques in Caffeic acid phenethyl ester group than in non-treated and saline groups (p < 0.05). TM thickness measurements were very close to each other in non-treated and saline groups. The tympanic membrane thickness of Caffeic acid phenethyl ester group was much thinner than the other two groups (p < 0.05). Caffeic acid phenethyl ester decreases inflammation severity and the formation of myringosclerotic plaques. These two effects resulted in thinner tympanic membranes of rats which were treated with Caffeic acid phenethyl ester. As a result, Caffeic acid phenethyl ester has potential preventive effects on myringosclerosis development after myringotomy and ventilation tube insertion.

Caffeic acid phenethyl ester, an inhibitor of nuclear factor-kappaB, attenuates bacterial peptidoglycan polysaccharide-induced colitis in rats.[Pubmed:11714876]

J Pharmacol Exp Ther. 2001 Dec;299(3):915-20.

Caffeic acid phenethyl ester (CAPE) is an anti-inflammatory component of propolis (honeybee resin). CAPE is reportedly a specific inhibitor of nuclear factor-kappaB (NF-kappaB). The aims of our study were 1) to evaluate the effect of CAPE on cytokine production, NF-kappaB, and apoptosis in two cell lines; 2) to assess the effect of CAPE on NF-kappaB in rats with peptidoglycan-polysaccharide (PG-PS)-induced colitis; and 3) to evaluate the efficacy of CAPE against this colitis. In vitro experiments used rat macrophage (NR8383) and colonic epithelial cell (SW620) lines. NF-kappaB was evaluated by electrophoretic mobility shift assay. Cytokines and apoptosis were measured by enzyme-linked immunosorbent assay. Colitis was induced by intramural injections of PG-PS into the distal colon. CAPE (30 mg/kg) or vehicle was administered once daily to rats by intraperitoneal injection, for 1 week. Various macroscopic and biochemical indices were measured on day 21. CAPE (30 microg/ml) significantly inhibited NF-kappaB and TNF-alpha production in the macrophage cell line. In macrophages, CAPE significantly increased DNA fragmentation. CAPE exhibited generally similar effects in the colonic epithelial cell line. CAPE treatment reduced the mean level of colonic NF-kappaB in rats. CAPE also induced a significant reduction in gross colonic injury. Moreover, colonic cytokine levels (TNF-alpha and IL-1beta) were significantly reduced in CAPE-treated rats. In summary, CAPE inhibits NF-kappaB, causes a reduction of pro-inflammatory cytokine production, and induces apoptosis in macrophages. These mechanisms likely contributed to the attenuation of PG-PS-induced colitis by CAPE.

Caffeic acid phenethyl ester as a lipoxygenase inhibitor with antioxidant properties.[Pubmed:7689063]

FEBS Lett. 1993 Aug 23;329(1-2):21-4.

Caffeic acid phenethyl ester, an active component of propolis extract, inhibits 5-lipoxygenase in the micromolar concentration range. The inhibition is of an uncompetitive type, i.e. the inhibitor binds to the enzyme-substrate complex but not to the free enzyme. Caffeic acid phenethyl ester also exhibits antioxidant properties. At a concentration of 10 microM, it completely blocks production of reactive oxygen species in human neutrophils and the xanthine/xanthine oxidase system.