Photo-triggered caffeic acid delivery via psyllium polysaccharide- gellan gum-based injectable bionanogel for epidermoid carcinoma treatment.

Here, the simultaneous effect of chemo- and photothermal therapy against epidermoid carcinoma (EC) was investigated. A novel hydrogel, termed bionanogel (BNG), was designed using psyllium mucilage polysaccharide and bacterial gellan gum, incorporated with nanocomplex carrying caffeic acid (CA) and IR-820, and further characterized. The dual effect of BNG and 808 nm laser (BNG + L) on EC was investigated. Staining and scratch assays were performed to analyze their therapeutic effect on EC. In vivo evaluations of BNG + L in xenograft models were performed. Rapid transition, limited swelling, degradability and high tensile strength indicated BNG stability and sustained drug release. Irradiation with 808 nm laser light at 1.25 W /cm2 for 4 min resulted in a temperature increase of 53 °C and facilitated cell ablation. The in vitro studies showed that BNG + L suppressed cancer progression via a late apoptotic effect. The in vivo study showed that the slow release of CA from BNG + L significantly attenuated EC with low mitotic index and downregulation of proteins involved in cancer proliferation such as EGFR, AKT, PI3K, ERK, mTOR and HIF-1α. Thus, BNG could be a novel medium for targeted and controlled drug delivery for the treatment of epidermoid cancer when triggered by NIR light.

Application of targeted liposomes-based salvianolic acid A for the treatment of ischemic stroke.

Novel therapeutics for the treatment of ischemic stroke remains to be the unmet clinical needs. Previous studies have indicated that salvianolic acid A (SAA) is a promising candidate for the treatment of the brain diseases. However, SAA has poor absolute bioavailability and does not efficiently cross the intact blood-brain barrier (BBB), which limit its efficacy. To this end we developed a brain-targeted liposomes for transporting SAA via the BBB by incorporating the liposomes to a transport receptor, insulin-like growth factor-1 receptor (IGF1R). The liposomes were prepared by ammonium sulfate gradients loading method. The prepared SAA-loaded liposomes (Lipo/SAA) were modified with IGF1R monoclonal antibody to generate IGF1R antibody-conjugated Lipo/SAA (IGF1R-targeted Lipo/SAA). The penetration of IGF1R-targeted Lipo/SAA into the brain was confirmed by labeling with Texas Red, and their efficacy were evaluate using middle cerebral artery occlusion (MCAO) model. The results showed that IGF1R-targeted Lipo/SAA are capable of transporting SAA across the BBB into the brain, accumulation in brain tissue, and sustained releasing SAA for several hours. Administration o IGF1R-targeted Lipo/SAA notably reduced infarct size and neuronal damage, improved neurological function and inhibited cerebral inflammation, which had much higher efficiency than no-targeted SAA.

Caffeic acid phenethyl ester targets ubiquitin-specific protease 8 and synergizes with cisplatin in endometrioid ovarian carcinoma cells.

Deubiquitinases (DUBs) mediate the removal of ubiquitin from diverse proteins that participate in the regulation of cell survival, DNA damage repair, apoptosis and drug resistance. Previous studies have shown an association between activation of cell survival pathways and platinum-drug resistance in ovarian carcinoma cell lines. Among the strategies available to inhibit DUBs, curcumin derivatives appear promising, thus we hypothesized their use to enhance the efficacy of cisplatin in ovarian carcinoma preclinical models. The caffeic acid phenethyl ester (CAPE), inhibited ubiquitin-specific protease 8 (USP8), but not proteasomal DUBs in cell-free assays. When CAPE was combined with cisplatin in nine cell lines representative of various histotypes a synergistic effect was observed in TOV112D cells and in the cisplatin-resistant IGROV-1/Pt1 variant, both of endometrioid type and carrying mutant TP53. In the latter cells, persistent G1 accumulation upon combined treatment associated with p27kip1 protein levels was observed. The synergy was not dependent on apoptosis induction, and appeared to occur in cells with higher USP8 levels. In vivo antitumor activity studies supported the advantage of the combination of CAPE and cisplatin in the subcutaneous model of cisplatin-resistant IGROV-1/Pt1 ovarian carcinoma as well as CAPE activity on intraperitoneal disease. This study reveals the therapeutic potential of CAPE in cisplatin-resistant ovarian tumors as well as in tumors expressing USP8.

Caffeic acid and its derivatives as potential modulators of oncogenic molecular pathways: New hope in the fight against cancer.

As a phenolic acid compound, caffeic acid (CA) can be isolated from different sources such as tea, wine and coffee. Caffeic acid phenethyl ester (CAPE) is naturally occurring derivative of CA isolated from propolis. This medicinal plant is well-known due to its significant therapeutic impact including its effectiveness as hepatoprotective, neuroprotective and anti-diabetic agent. Among them, anti-tumor activity of CA has attracted much attention, and this potential has been confirmed both in vitro and in vivo. CA can induce apoptosis in cancer cells via enhancing ROS levels and impairing mitochondrial function. Molecular pathways such as PI3K/Akt and AMPK with role in cancer progression, are affected by CA and its derivatives in cancer therapy. CA is advantageous in reducing aggressive behavior of tumors via suppressing metastasis by inhibiting epithelial-to-mesenchymal transition mechanism. Noteworthy, CA and CAPE can promote response of cancer cells to chemotherapy, and sensitize them to chemotherapy-mediated cell death. In order to improve capacity of CA and CAPE in cancer suppression, it has been co-administered with other anti-tumor compounds such as gallic acid and p-coumaric acid. Due to its poor bioavailability, nanocarriers have been developed for enhancing its ability in cancer suppression. These issues have been discussed in the present review with a focus on molecular pathways to pave the way for rapid translation of CA for clinical use.

Safety assessment of a newly synthesized copolymer for micellar delivery of hydrophobic caffeic acid phenethyl ester.

Caffeic acid phenethyl ester (CAPE), a major pharmacologically active component of poplar type propolis, is known for its proapoptotic, anti-inflammatory, antioxidant, antiviral, and enzyme inhibiting activities. The aim of this study was to perform an in vitro and in vivo safety assessment of a micellar system based on a newly synthesized copolymer, consisting of polyglycidol and poly(allyl glycidyl ether) (C12-PAGE-PG) as a drug delivery platform for CAPE. The in vitro studies on HepG2 and L929 cells by MTT and LDH assays after treatment with the empty and CAPE-loaded micelles showed no cytotoxic effects of the empty micelles and retained cytotoxic activity of CAPE loaded in the micelles. No hemolysis or stimulation of mouse lymphocytes or macrophages was observed in vitro. In vivo hematological, biochemical, and histological assays on rats, treated with the empty (2580 and 5160 µg/kg) or CAPE-loaded (375 and 750 µg CAPE/kg) micelles did not reveal pathological changes of any of the parameters assayed after 14-days' treatment. In conclusion, initial toxicological data characterize C12-PAGE-PG as a non-toxic and promising copolymer for development of micellar drug delivery systems, particularly for a hydrophobic active substance as CAPE.

Ethyl ferulate/ß-cyclodextrin inclusion complex inhibits edema formation.

Ethyl ferulate, a phenylpropanoid derived from rice hulls has aroused interest because of its antioxidant, anti-inflammatory and neuroprotective properties. However, it has low solubility in water which compromises the absorption in the gastrointestinal tract, decreases the bioavailability and compromises the reproducibility of the effects in vivo. To increase the solubility of ethyl ferulate, inclusion complexes were obtained by physical mixing, malaxing, lyophilization and spray drying and characterized using thermal analysis, XRD and FTIR. The complexes obtained were evaluated for ethyl ferulate content, stability, dissolution profile and evaluation of anti-inflammatory activity in vivo through carrageenan-induced paw edema model in rats. The inclusion complexes obtained resulted in increased solubility and stability compared to the isolated ethyl ferulate. In addition, the complexes obtained by malaxage, lyophilization and spray drying showed greater inhibition of the edema formation induced by carrageenan compared to ethyl ferulate 100 mg/kg v.o. The inclusion of ethyl ferulate in B-cyclodextrin resulted in the formation of stable inclusion complexes with potent antidematogenic activity possibly attributed to the increased solubility, dissolution profile of the active.

Danggui Buxue decoction ameliorates lipid metabolic defects involved in the initiation of diabetic atherosclerosis; identification of active compounds.

OBJECTIVE: To determine the constituent compounds of Danggui buxue decoction (DBD) involved and the potential mechanisms mediating its effects, with specific reference to lipids playing a role in the initiation of diabetic atherosclerosis. METHODS: Liquid chromatography-tandem mass spectrometry was used to identify and quantify the absorbed bioactive compounds (ABCs) present in DBD. Goto-Kakizaki (GK) rats were randomly allocated to a diabetes atherosclerosis (DA) group, a DBD group, and an ABC group (10 per group), which were all high-fat diet-fed. The treated rats were administered DBD (4 g/kg) or ABCs (in amounts equal to those present in DBD) once daily for 28 d, and a control group of Wistar rats were administered vehicle. Body mass gain, fasting blood glucose, and homeostasis assessment of insulin resistance (HOMA- IR) were measured. Serum triglyceride (TG), cholesterol (CHOL), high density lipoprotein-cholesterol (HDL-C), low-density lipoprotein-cholesterol (LDL- C) and tumor necrosis factor-α (TNF-α) concentrations were determined. Hematoxylin and eosin staining and microscopy were used to characterize the abdominal aorta and the expression of lipogenic genes was quantified in this vessel. RESULTS: Seven ABCs were identified in rat serum: ferulic acid, formononetin, calycosin, astragaloside, caffeic acid, ligustilide, and butyphthalide. DBD significantly reduced HOMA-IR, the serum concentrations of TG, CHOL, and LDL-C, and the expression of the lipogenic genes monocyte chemotactic protein 1, Fas, intercellular adhesion molecule 1, and Cd36 in aorta; and significantly increased the mRNA expression of Scd1 in aorta. CONCLUSION: DBD affects lipid metabolism in the early stage of atherosclerosis in diabetic GK rats, with the mechanism likely involving the regulation of lipid metabolic genes in vessels. The contribution of ABCs to the effect of DBD on lipid metabolism was 24%-101%.

High cholesterol diet promotes dysfunction of arginase and cholinergic enzymatic system in rats: ameliorative role of caffeic and chlorogenic acids.

BACKGROUND: Dietary phenolic compounds intake have been reported to have an inverse relationship to the prevalence of hypercholesterolemia. The objective of this study is to determine the effect of caffeic acid (CFA) and chlorogenic acid (CGA) on rats fed with high cholesterol diet (HCD). METHODS: Experimental animals were fed with high cholesterol diet (HCD) for a period of 21 days while simvastatin (0.2 mg/kg BWT), CFA and CGA (10 and 15 mg/kg BWT) were administered daily. RESULTS: Activity of acetylcholinesterase (AChE), butyrylcholinesterase (BChE) and arginase were significantly (P<0.05) higher in the rats fed with HCD alone. Also, level of malondiadehyde equivalent compounds (MDA) was significantly (P<0.05) elevated in hypercholesterolemic rats. Nevertheless, treatment with simvastatin, CFA and CGA normalized altered AChE, BChE and arginase activities as well as improved antioxidant status in hypercholesterolemic rats. CONCLUSION: CFA and CGA could offer protective role in hypercholeseterolemic rats via their antioxidant potentials as well as restoring altered activity of acetylcholinesterase, butrylcholinesterase and arginase. Based on our findings chlorogenic acid exhibits better attribute.

Decyl caffeic acid inhibits the proliferation of colorectal cancer cells in an autophagy-dependent manner in vitro and in vivo.

The treatment of human colorectal cancer (CRC) cells through suppressing the abnormal survival signaling pathways has recently become a significant area of focus. In this study, our results demonstrated that decyl caffeic acid (DC), one of the novel caffeic acid derivatives, remarkedly suppressed the growth of CRC cells both in vitro and in vivo. The inhibitory effects of DC on CRC cells were investigated in an in vitro cell model and in vivo using a xenograft mouse model. CRC cells were treated with DC at various dosages (0, 10, 20 and 40 µM), and cell survival, the apoptotic index and the autophagy level were measured using an MTT assay and flow cytometry analysis, respectively. The signaling cascades in CRC were examined by Western blot assay. The anti-cancer effects of DC on tumor growth were examined by using CRC HCT-116 cells implanted in an animal model. Our results indicated that DC differentially suppressed the growth of CRC HT-29 and HCT-116 cells through an enhancement of cell-cycle arrest at the S phase. DC inhibited the expression of cell-cycle regulators, which include cyclin E and cyclin A proteins. The molecular mechanisms of action were correlated to the blockade of the STAT3 and Akt signaling cascades. Strikingly, a high dosage of DC prompted a self-protection action through inducing cell-dependent autophagy in HCT-116 cells. Suppression of autophagy induced cell death in the treatment of DC in HCT-116 cells. DC seemed to inhibit cell proliferation of CRC differentially, and the therapeutic advantage appeared to be autophagy dependent. Moreover, consumption of DC blocked the tumor growth of colorectal adenocarcinoma in an experimental animal model. In conclusion, our results suggested that DC could act as a therapeutic agent through the significant suppression of tumor growth of human CRC cells.

Pharmacokinetic study of tanshinol and ligustrazine in rat plasma after intravenous administration of tanshinol and Danshen Chuanxiongqin Injection.

To investigate the effect of ligustrazine on the pharmacokinetic profile of tanshinol after intravenous administration in rats, a sensitive liquid chromatography tandem mass spectrometry method was developed and validated for quantitative determination of tanshinol and ligustrazine in rat plasma. After prepared by protein precipitation, the analytes were separated on a Waters Acquity HSS T3 column (100 × 2.1 mm, 1.8µm) and eluted by 0.1% formic acid in water and acetonitrile at a flow rate of 0.4 ml/min. The precursor-product ion transitions were m/z 197.0 → 135.0 for tanshinol, m/z 417.1 → 255.1 for liquiritin (internal standard) in negative ion mode and m/z 137.1 → 55.0 for ligustrazine in positive ion mode. To avoid the interference of tanshinol metabolite transformation, the stability of analytes in samples collected after administration was assessed. The validated method was successfully applied to a pharmacokinetic study after intravenous administration of single tanshinol and Danshen Chuanxiongqin Injection. After Danshen Chuanxiongqin injection administration, the values of elimination half-time, area under the concentration-time curve and Co were 0.36 ± 0.13 h, 1.29 ± 0.37 µg/ml h and 10.51 ± 2.58 µg/ml for male rats, respectively. In the single tanshinol group, the corresponding values were 0.56 ± 0.24 h, 1.85 ± 0.44 µg/ml h and 14.11 ± 2.26 µg/ml for male rats-30-40% higher than those for the Danshen Chuanxiongqin Injection group. There was a significant different between male and female rats. This study provided information on the influence of ligustrazine on the pharmacokinetic characteristics of tanshinol after intravenous administration of Danshen Chuanxiongqin Injection in rats, which will be helpful for its clinical application.

UFLC-MS/MS Determination and Population Pharmacokinetic Study of Tanshinol, Ginsenoside Rb1 and Rg1 in Rat Plasma After Oral Administration of Compound Danshen Dripping Pills.

BACKGROUND AND OBJECTIVES: As a traditional Chinese Materia Medica (CMM), the Compound Danshen Dripping Pill (CDDP) is widely used for the treatments of cardiovascular diseases. In view of its undefined applicable population and dosage, a population pharmacokinetic (PPK) study is required. The objective of this study was to explore the feasibility of multi-component CMM PPK in rat plasma after oral administration of CDDP based on sparse sampling. METHODS: In this research, a simple, rapid and highly sensitive UFLC-MS/MS method for the simultaneous determination of tanshinol (TSL), ginsenoside Rb1 (GRb1) and ginsenoside Rg1 (GRg1) has been successfully developed in rat plasma. Moreover, the validated method has been applied to a PPK study of CDDP based on sparse data. We established the PPK models for these three main active constituents using a nonlinear mixed-effects model, taking into account of factors such as gender, age in weeks and weight. RESULTS: The PPK models of TSL and GRb1 were best described by a one-compartment model with linear elimination and first-order absorption. The model of GRg1 was best described by a two-compartment model with first-order absorption. Bootstrap validation and a visual predictive check confirmed the predictive ability, the model stability and the precision of the parameter estimates from these models. CONCLUSION: As a preliminary exploration toward the clinical population pharmacokinetic research, this study provides a reference for the population pharmacokinetic study of traditional CMM.

The Impact of Propolis Factor Caffeic Acid Phenethyl-Ester on the Cerebral Vasospasm and Early Brain Damage in the Experimentally Induced Subarachnoid Hemorrhage on Rats.

OBJECTIVE: Caffeic acid phenethyl ester (CAPE), a phenolic compound, besides being 1 of the biologically active components of propolis, is a compound with antioxidant, antiinflammatory, antiviral, reperfusion damage prevention, immune stimulant, and carcinostatic, anticancer properties. The aim of this study was to investigate the possible effects of CAPE on cerebral vasospasm and early brain injury, which were experimentally administered intraperitoneally in rats with subarachnoid hemorrhage. METHODS: Thirty-two Wistar Albino rats weighing 200 to 300 g were used in our study. The rats divided into 3 groups: the control group (n = 10), subarachnoid hemorrhage group (n = 11), and subarachnoid hemorrhage + CAPE group (n = 11). These groups were evaluated according to the Ischemia index in hippocampal CA3 regions and the morphometric analysis of basilar artery diameter after being sacrificed at the end of 72nd hour. RESULTS: A significant difference was found between group 1 and group 2 for the CA-3 region, it was concluded that early brain damage occurred after subarachnoid hemorrhage. When the neuronal damage in CA-3 region was evaluated between group 2 and group 3, a statistically significant difference was found between the groups. There was a statistically significant difference between group 1 and group 3 in terms of ischemia detection. CONCLUSIONS: It was shown that CAPE has a preventive effect on early brain injury after subarachnoid hemorrhage and has a positive effect on reducing cerebral vasospasm. Our study is the first study in the literature showing that CAPE inhibits ischemic brain injury following subarachnoid hemorrhage.

Salvianolic acid A increases the accumulation of doxorubicin in brain tumors through Caveolae endocytosis.

Brain glioma is one of the most common brain tumors in the central nervous system (CNS). The blood-brain tumor barrier (BTB) restricts the delivery of anti-tumor drugs into tumor tissue in the brain. Therefore, improving the transportation of antineoplastic drugs across the BTB is essential to ameliorate treatment of brain tumors. The present study was performed to explore the effect and mechanism of salvianolic acid A (Sal A) on transportation of doxorubicin (Dox) across the BTB in vivo and in vitro. By creating a brain C6 glioma model in rats, we demonstrated that Sal A significantly increased the level of Dox in brain tumor tissue as shown by liquid chromatograph mass spectrometry. Interestingly, we found that Sal A increased transendothelial electrical resistance (TEER) values of the BTB and decreased the permeability of FITC-Dextran (4kD) across the BTB in vitro. Furthermore, the expression of tight junction proteins (TJs) in glioma endothelial cells (GECs) and brain tumor microvessels were also increased, suggesting that Sal A enhanced delivery of Dox across the BTB independent of the paracellular pathway. Next, we detected that Sal A had an effect on transcellular transport of compounds across the BTB. The accumulation of FITC-labeled bovine serum albumin (FITC-BSA) was significantly increased in GECs after treatment with Sal A (10 µM) for 6h, which was inhibited after pre-treatment with methyl-ß-cyclodextrin (MßCD) for 30 min. The increased delivery of Dox across the BTB was also reduced after treatment with MßCD. In addition, phosphorylation levels of protein kinase B (PKB) and tyrosine protein kinase-Src family (Src) were increased in the Sal A treatment group. Sal A up-regulated the expression level of the phosphorylation of Caveolin-1 (pCaveolin-1), and this effect was reversed by a PKB or Src inhibitor. Taken together, our study showed for the first time that Sal A facilitated the delivery of antitumor drugs into brain tumor tissues by targeting the PKB/Src/Caveolin-1 signaling pathway.

Tanshinol A Ameliorates Triton-1339W-Induced Hyperlipidemia and Liver Injury in C57BL/6J Mice by Regulating mRNA Expression of Lipemic-Oxidative Injury Genes.

Tanshinol A, which is derived from a traditional Chinese herbal Radix Salviae Miltiorrhizae is indicative of a hypolipidemic candidate. Therefore, we aim to validate its hypolipidemic activity of tanshinol A and explore its mechanism in triton-1339W-induced hyperlipidemic mice model, which possess multiply pathogenesis for endogenous lipid metabolism disorder. Experimental hyperlipidemia mice are treated with or without tanshinol A (i.g. 40, 20, 10 mg/kg), and blood and liver tissue were collected for validating its hypolipidemic and hepatic protective effect, and hepatic mRNA expression profile, which was associated with lipid metabolism dysfunction and liver injury, was detected by RT-qPCR. As results show, triton-1339W-induced abnormal of serum TC, TAG, HDL-C, LDL-C, SOD, MDA, GOT, and GPT is remarkably attenuated by tanshinol A. In pathological experiment, triton-1339W-induced hepatocellular ballooning degeneration, irregular central vein congestion, and inflammation infiltration are alleviated by tanshinol A. Correspondingly, hepatic mRNA expression of Atf4, Fgf21, Vldlr, Nqo1, Pdk4, and Angptl4, which are genes regulating lipemic-oxidative injury, are significantly increased by tanshinol A by 2~6 fold. Abcg5, Cd36, and Apob, which are responsible for cholesterol metabolism, are mildly upregulated. Noticeably, triton-1339W-suppressed expressions of Ptgs2/Il10, which are genes responsible for acute inflammation resolution in liver injury, are remarkably increased by tanshinol A. Conclusively, tanshinol A exerted hypolipidemic effect and hepatoprotective effect through restoring triton-1339W-suppressed mRNA expression, which may be involved in Atf4/Fgf21/Vldlr and Ptgs2/Il-10 signaling pathways.

The combination of salvianolic acid A with latamoxef completely protects mice against lethal pneumonia caused by methicillin-resistant Staphylococcus aureus.

Staphylococcus aureus (S. aureus), especially methicillin-resistant Staphylococcus aureus (MRSA), is a major cause of pneumonia, resulting in severe morbidity and mortality in adults and children. Sortase A (SrtA), which mediates the anchoring of cell surface proteins in the cell wall, is an important virulence factor of S. aureus. Here, we found that salvianolic acid A (Sal A), which is a natural product that does not affect the growth of S. aureus, could inhibit SrtA activity (IC50 = 5.75 µg/ml) and repress the adhesion of bacteria to fibrinogen, the anchoring of protein A to cell wall, the biofilm formation, and the ability of S. aureus to invade A549 cells. Furthermore, in vivo studies demonstrated that Sal A treatment reduced inflammation and protected mice against lethal pneumonia caused by MRSA. More significantly, full protection (a survival rate of 100%) was achieved when Sal A was administered in combination with latamoxef. Together, these results indicate that Sal A could be developed into a promising therapeutic drug to combat MRSA infections while limiting resistance development.

Quantitative determination of characteristic components from compound of Lysionotus pauciflorus Maxim. by LC-MS/MS and its application to a pharmacokinetic study.

Tuberculosis of cervical lymph nodes is called scrofula in Traditional Chinese Medicine (TCM). Clinical manifestation is that unilateral or bilateral neck can have multiple enlarged lymph nodes of different sizes. Current therapeutic drugs include Lysionotus pauciflorus Maxim. tablets and compound of Lysionotus pauciflorus Maxim., which have a significant effect on tuberculosis of cervical lymph nodes. This compound is composed of three herbs, Lysionotus pauciflorus Maxim., Prunella vulgaris L. and Artemisia argyi Levl.et Vant. A selective and sensitive LC-MS/MS method was established and validated in rat plasma for the first time. Chromatographic separation was achieved on a Wonda Cract ODS-2 C18 Column (150 mm × 4.6 mm, 5 µm). The mobile phase contained 0.1% formic acid aqueous solution and acetonitrile with a flow rate of 0.8 mL/min. The detection was performed in negative electrospray ionization mode and the precursor/product ion transitions of six components and internal standard (IS) sulfamethoxazole were quantified in multiple reaction monitoring (MRM) using QTRAP-3200 MS/MS. The method fulfilled US Food and Drug Administration guidelines for selectivity, sensitivity, accuracy, precision, matrix effect, extraction recovery, dilution integrity, and stability. This proposed method was then successfully applied to a pharmacokinetic study after oral administration of 10 mL/kg compound extracts in rats. The pharmacokinetic parameters and plasma concentration-time profiles would prove valuable in pre-clinical and clinical investigations on the disposition of compound medicine.

Protective Effect of Caffeic Acid against Alzheimer's Disease Pathogenesis via Modulating Cerebral Insulin Signaling, ß-Amyloid Accumulation, and Synaptic Plasticity in Hyperinsulinemic Rats.

This study investigated the alleviative effect of caffeic acid (CA) on Alzheimer's disease (AD) pathogenesis and associated mechanisms in high-fat (HF) diet-induced hyperinsulinemic rats. The results of a Morris water maze indicated that, by administrating CA (30 mg/kg b.w./day) for 30 weeks, the memory and learning impairments in HF-induced hyperinsulinemic rats were significantly ameliorated. CA also enhanced superoxide dismutase and glutathione free radical scavenger activity in hyperinsulinemic rats. The Western blot data further confirmed that protein expressions of phosphorylated-glycogen synthase kinase 3ß (GSK3ß) were significantly increased, whereas the expression of phosphorylated-tau protein decreased in the hippocampus of rats administered with CA in comparison with the HF group. Moreover, the expression of amyloid precursor protein (APP) and ß-site APP cleaving enzyme were attenuated, subsequently lowering the level of ß-amyloid 1-42 (Aß 1-42) in the hippocampus of CA-treated hyperinsulinemic rats. CA also significantly increased the expression of synaptic proteins in HF rats.

Protective Effects of Caffeic Acid Phenethyl Ester (CAPE) and Novel Cape Analogue as Inducers of Heme Oxygenase-1 in Streptozotocin-Induced Type 1 Diabetic Rats.

Type 1 diabetes mellitus (T1D) is a chronic autoimmune disease resulting in the destruction of insulin producing ß-cells of the pancreas, with consequent insulin deficiency and excessive glucose production. Hyperglycemia results in increased levels of reactive oxygen species (ROS) and nitrogen species (RNS) with consequent oxidative/nitrosative stress and tissue damage. Oxidative damage of the pancreatic tissue may contribute to endothelial dysfunction associated with diabetes. The aim of the present study was to investigate if the potentially protective effects of phenethyl ester of caffeic acid (CAPE), a natural phenolic compound occurring in a variety of plants and derived from honeybee hive propolis, and of a novel CAPE analogue, as heme oxygenase-1 (HO-1) inducers, could reduce pancreatic oxidative damage induced by excessive amount of glucose, affecting the nitric oxide synthase/dimethylarginine dimethylaminohydrolase (NOS/DDAH) pathway in streptozotocin-induced type 1 diabetic rats. Our data demonstrated that inducible nitric oxide synthase/gamma-Glutamyl-cysteine ligase (iNOS/GGCL) and DDAH dysregulation may play a key role in high glucose mediated oxidative stress, whereas HO-1 inducers such as CAPE or its more potent derivatives may be useful in diabetes and other stress-induced pathological conditions.

Effect of Caffeic Acid on Ischemia-Reperfusion-Induced Acute Renal Failure in Rats.

BACKGROUND: Cyclooxygenase (COX)-lipooxygenase (LOX) pathway plays a key role in the pathogenesis of renal ischemia/reperfusion (IR). OBJECTIVE: This study was aimed to evaluate the role of dietary phenol caffeic acid (CA), alone and in combination with selective COX-2 inhibitor celecoxib (CEL) in IR-induced acute renal failure (ARF) in rats. MATERIALS AND METHODS: Renal IR was induced by bilateral occlusion of renal pedicels for 90 min followed by reperfusion for 24 h. Rats were randomized into 4 groups: Sham, IR, CA + IR, and CA + CEL + IR, with 7 day treatment before IR. Serum creatinine (SCr), blood urea nitrogen (BUN), antioxidant enzymes, tumor necrosis factor alpha (TNF-α), and histopathological changes were evaluated in the kidney after IR. RESULTS: Renal IR caused significant derangement in renal function and histology. In the IR group, an increase in lipid peroxidation and decreased antioxidant defense enzyme activity were observed. Pretreatment with CA and CA + CEL showed a significant decrease in the BUN, SCr, TNF-α, oxidative stress markers and corrected the histological changes in the kidney. CONCLUSION: This study demonstrated the renoprotective potential of CA and combination of CA + CEL in IR-induced ARF in rats. The plausible mechanisms for the efficacy of CA could be attributed to its ability to modulate the -COX-LOX system in renal IR.

Effects of Enteric Environmental Modification by Coffee Components on Neurodegeneration in Rotenone-Treated Mice.

Epidemiological studies have shown that coffee consumption decreases the risk of Parkinson's disease (PD). Caffeic acid (CA) and chlorogenic acid (CGA) are coffee components that have antioxidative properties. Rotenone, a mitochondrial complex I inhibitor, has been used to develop parkinsonian models, because the toxin induces PD-like pathology. Here, we examined the neuroprotective effects of CA and CGA against the rotenone-induced degeneration of central dopaminergic and peripheral enteric neurons. Male C57BL/6J mice were chronically administered rotenone (2.5 mg/kg/day), subcutaneously for four weeks. The animals were orally administered CA or CGA daily for 1 week before rotenone exposure and during the four weeks of rotenone treatment. Administrations of CA or CGA prevented rotenone-induced neurodegeneration of both nigral dopaminergic and intestinal enteric neurons. CA and CGA upregulated the antioxidative molecules, metallothionein (MT)-1,2, in striatal astrocytes of rotenone-injected mice. Primary cultured mesencephalic or enteric cells were pretreated with CA or CGA for 24 h, and then further co-treated with a low dose of rotenone (1⁻5 nM) for 48 h. The neuroprotective effects and MT upregulation induced by CA and CGA in vivo were reproduced in cultured cells. Our data indicated that intake of coffee components, CA and CGA, enhanced the antioxidative properties of glial cells and prevents rotenone-induced neurodegeneration in both the brain and myenteric plexus.