Caffeic Acid and Diseases-Mechanisms of Action

Caffeic acid belongs to the polyphenol compounds we consume daily, often in the form of coffee. Even though it is less explored than caffeic acid phenethyl ester, it still has many positive effects on human health. Caffeic acid can affect cancer, diabetes, atherosclerosis, Alzheimer's disease, or bacterial and viral infections. This review focuses on the molecular mechanisms of how caffeic acid achieves its effects.

Oral Pharmacokinetics of Hydroxycinnamic Acids: An Updated Review

Hydroxycinnamic acids (HCAs) such as caffeic acid (CA), chlorogenic acid (CGA), coumaric acid (COA) isomers, ferulic acid (FA) and rosmarinic acid (RA) are natural phenolic acids with widespread distribution in vegetal foods and well-documented pharmacological activities. However, the low bioavailability of HCAs impairs their administration by the oral route. The present review addresses new findings and important factors/obstacles for their oral administration, which were unexplored in the reviews published a decade ago concerning the bioavailability of phenolic acids. Based on this, the article aims to perform an updated review of the water solubility and gastrointestinal stability of HCAs, as well as describe their oral absorption, distribution, metabolism and excretion (ADME) processes by in vitro, ex vivo, in situ and in vivo methods.

Beneficial herb-drug interaction of Gnaphalium affine extract on benzbromarone: A pharmacokinetic and pharmacodynamic study in rats

BACKGROUND

Gnaphalium affine D. Don extract (GAD) enhanced efficacy and reduced toxicity of benzbromarone (BBR) in combination use. However, little is known about effects of GAD on the pharmacokinetics (PKs) and metabolic enzymes of BBR.

PURPOSE

To investigate the pharmacokinetic (PK) and pharmacodynamic (PD) mechanism of the herb-drug interactions (HDIs) between GAD and BBR.

STUDY DESIGN AND METHODS

Intragastric single BBR (4.5 or 50 mg/kg), single BBR (4.5 or 50 mg/kg) + single GAD (450 mg/kg, 2 h after BBR-administration), or single BBR (4.5 or 50 mg/kg) + multiple GAD (450 mg/kg/day, once daily for 7 days) were administered to both sexes for BBR PK studies in normal rats. Intragastric multiple BBR (4.5 mg/kg/day), or multiple BBR (4.5 mg/kg/day) + multiple GAD (450 mg/kg/day, 2 h after BBR-administration) were administered for BBR PK and PD studies in male rats with hyperuricemic nephropathy (HN). The cumulative anti-hyperuricemic effects of BBR and BBR+GAD were determined by plasma uric acid (UA) concentration-time curve and area under curve (AUC_UA). An in vivo cocktail approach was employed to determine the effects of GAD on cytochrome P450 (CYP) 2C11(9) and 1A2 - mediated drug metabolism.

RESULTS

In normal rats, the repeated dose administration of GAD induced a significant increase of BBR AUC and prolonged the mean residence time (MRT) (p < 0.05). systemic exposure to BBR and metabolically derived hydroxybenzbromarones was significantly greater in female compared with male rats (p < 0.05). In HN rats, post-administration of GAD resulted in significantly higher bioavailability and enterohepatic recycling (ER) of BBR relative to the BBR alone administrated group from the prolongation of terminal elimination half-life (T_1/2) and MRT of BBR (p < 0.05). Significantly higher urate-lowering effect of BBR+GAD compared with BBR alone was generally observed at post-dosing most time points with a maximal effect of 84.3% (acute treatment), 71.4% (7-day subchronic treatment) and 82.5% (14-day subchronic treatment) reduction in UA levels. Additionally, GAD showed a significant inhibitory effect on CYP2C11(9)-mediated tolbutamide (probe substrate) metabolism with ≥ 1.25 but < 2-fold increase in AUC_tolbutamide.

CONCLUSIONS

PD synergism demonstrated with the BBR+GAD combination could be explained by the PK interaction observed partially from CYP2C11(9)-mediation and enterohepatic recycling.

Evaluation of potential herb-drug interactions based on the effect of Suxiao Jiuxin Pill on CYP450 enzymes and transporters

ETHNOPHARMACOLOGY RELEVANCE

Suxiao jiuxin pill (SJP) is a Chinese medical drug with anti-inflammatory, anti-apoptotic, and vasodilatory function. It is widely used in combination with other drugs for the treatment of coronary heart disease (CHD) and angina. Nevertheless, the effect of SJP on Cytochrome P450 (CYP450) enzymes and transporters' activity related to drug metabolism is rarely studied.

OBJECTIVE

The aim of this study was to investigate the effect of SJP on the activity of drug-metabolizing enzyme CYP450 and transporters.

MATERIALS AND METHODS

Human primary hepatocytes were used in present study. Probe substrates of CYP450 enzymes were incubated in human liver microsomes (HLMs) with and without SJP while IC₅₀ values were calculated. The inhibitory effect of SJP on the activity of CYP1A2, 2B6, 2C8, 2C9, 2C19, 2D6 and 3A4 was evaluated. The inducing effect of SJP on the activity of CYP1A2, 2B6 and 3A4 was accessed. The inhibition of SJP on human OATP1B1 was investigated through cell-based assay. The inhibition of SJP on human MDR1 and BCRP was also estimated by means of the vesicles assay.

RESULTS

The results showed that the SJP under the concentration of 1000 μg/mL could inhibit the activity of CYP1A2, 2B6, 2C19, and 3A4, with IC₅₀ values of 189.7, 308.2, 331.2 and 805.7 μg/mL, respectively. There was no inhibitory effect found in the other 3 liver drug enzyme subtypes. In addition, SJP showed no induction effect on CYP1A2, 2B6 and 3A4, however it had a significant inhibitory effect on human-derived OATP1B1 at the concentration of 100 and 1000 μg/mL, with the IC₅₀ value of 21.9 μg/mL. Simultaneously, the SJP inhibited BCRP at high concentration of 1000 μg/mL but did not affect human MDR1.

CONCLUSIONS

Based on these research results above, it is suggested that the SJP can affect some of the CYP450 enzymes and transporters' activity. When used in combination with related conventional drugs, potential herb-drug interactions should be considered.

Novel insights into the molecular mechanisms underlying risk of colorectal cancer from smoking and red/processed meat carcinogens by modeling exposure in normal colon organoids

Tobacco smoke and red/processed meats are well-known risk factors for colorectal cancer (CRC). Most research has focused on studies of normal colon biopsies in epidemiologic studies or treatment of CRC cell lines in vitro. These studies are often constrained by challenges with accuracy of self-report data or, in the case of CRC cell lines, small sample sizes and lack of relationship to normal tissue at risk. In an attempt to address some of these limitations, we performed a 24-hour treatment of a representative carcinogens cocktail in 37 independent organoid lines derived from normal colon biopsies. Machine learning algorithms were applied to bulk RNA-sequencing and revealed cellular composition changes in colon organoids. We identified 738 differentially expressed genes in response to carcinogens exposure. Network analysis identified significantly different modules of co-expression, that included genes related to MSI-H tumor biology, and genes previously implicated in CRC through genome-wide association studies. Our study helps to better define the molecular effects of representative carcinogens from smoking and red/processed meat in normal colon epithelial cells and in the etiology of the MSI-H subtype of CRC, and suggests an overlap between molecular mechanisms involved in inherited and environmental CRC risk.

Potential Herb-Drug Interactions in the Management of Age-Related Cognitive Dysfunction

Late-life mild cognitive impairment and dementia represent a significant burden on healthcare systems and a unique challenge to medicine due to the currently limited treatment options. Plant phytochemicals have been considered in alternative, or complementary, prevention and treatment strategies. Herbals are consumed as such, or as food supplements, whose consumption has recently increased. However, these products are not exempt from adverse effects and pharmacological interactions, presenting a special risk in aged, polymedicated individuals. Understanding pharmacokinetic and pharmacodynamic interactions is warranted to avoid undesirable adverse drug reactions, which may result in unwanted side-effects or therapeutic failure. The present study reviews the potential interactions between selected bioactive compounds (170) used by seniors for cognitive enhancement and representative drugs of 10 pharmacotherapeutic classes commonly prescribed to the middle-aged adults, often multimorbid and polymedicated, to anticipate and prevent risks arising from their co-administration. A literature review was conducted to identify mutual targets affected (inhibition/induction/substrate), the frequency of which was taken as a measure of potential interaction. Although a limited number of drugs were studied, from this work, interaction with other drugs affecting the same targets may be anticipated and prevented, constituting a valuable tool for healthcare professionals in clinical practice.

Caffeic Acid Phenethyl Ester Assisted by Reversible Electroporation-In Vitro Study on Human Melanoma Cells

Melanoma is one of the most serious skin cancers. The incidence of this malignant skin lesion is continuing to increase worldwide. Melanoma is resistant to chemotherapeutic drugs and highly metastatic. Surgical resection can only be used to treat melanoma in the early stages, while chemotherapy is limited due to melanoma multi-drug resistance. The overexpression of glutathione S-transferase (GST) may have a critical role in this resistance. Caffeic acid phenethyl ester (CAPE) is a natural phenolic compound, which occurs in many plants. Previous studies demonstrated that CAPE suppresses the growth of melanoma cells and induces reactive oxygen species generation. It is also known that bioactivation of CAPE to its corresponding quinone metabolite by tyrosinase would lead to GST inhibition and selective melanoma cell death. We investigated the biochemical toxicity of CAPE in combination with microsecond electropermeabilization in two human melanoma cell lines. Our results indicate that electroporation of melanoma cells in the presence of CAPE induced high oxidative stress, which correlates with high cytotoxicity. Moreover, it can disrupt the metabolism of cancer cells by inducing apoptotic cell death. Electroporation of melanoma cells may be an efficient CAPE delivery system, enabling the application of this compound, while reducing its dose and exposure time.

ABC Transporters: Regulation and Association with Multidrug Resistance in Hepatocellular Carcinoma and Colorectal Carcinoma

For most cancers, the treatment of choice is still chemotherapy despite its severe adverse effects, systemic toxicity and limited efficacy due to the development of multidrug resistance (MDR). MDR leads to chemotherapy failure generally associated with a decrease in drug concentration inside cancer cells, frequently due to the overexpression of ABC transporters such as P-glycoprotein (P-gp/MDR1/ABCB1), multidrug resistance-associated proteins (MRPs/ABCCs), and breast cancer resistance protein (BCRP/ABCG2), which limits the efficacy of chemotherapeutic drugs. The aim of this review is to compile information about transcriptional and post-transcriptional regulation of ABC transporters and discuss their role in mediating MDR in cancer cells. This review also focuses on drug resistance by ABC efflux transporters in cancer cells, particularly hepatocellular carcinoma (HCC) and colorectal carcinoma (CRC) cells. Some aspects of the chemotherapy failure and future directions to overcome this problem are also discussed.

Differentiated Caco-2 cell monolayers exhibit adaptation in the transport and metabolism of flavan-3-ols with chronic exposure to both isolated flavan-3-ols and enriched extracts

Chronic exposure to commonly consumed flavonoids changes their transport and metabolism in a small intestinal cell model.

Absorption properties and effects of caffeic acid phenethyl ester and its p-nitro-derivative on P-glycoprotein in Caco-2 cells and rats

CONTEXT

Caffeic acid phenethyl ester (CAPE), isolated from honeybee propolis, has pharmacological applications. A synthesized CAPE derivative, p-nitro-caffeic acid phenethyl ester (CAPE-NO₂), showed similar activities with CAPE. The pharmacological activities of CAPE and CAPE-NO₂ are related to their absorption properties.

OBJECTIVE

To understand the pharmacokinetic profiles of CAPE and CAPE-NO₂ in rats and investigate the absorption mechanisms and effects on P-glycoprotein in Caco-2 cells.

MATERIALS AND METHODS

The pharmacokinetic profiles of CAPE and CAPE-NO₂ were obtained after oral administration (10 mg/kg) to rats. Transport studies of CAPE and CAPE-NO₂ (5, 10, 20 μM) were performed in Caco-2 cell model. P-gp activities were assayed by rhodamine 123 cellular retention. Expression of P-gp was determined after the cells were administrated with CAPE and CAPE-NO₂ (5, 20 μM) for 48 and 72 h.

RESULTS

The AUC_(0-t) of CAPE-NO₂ (3239.9 ± 352 ng × h/mL) was two-time greater than CAPE (1659.6 ± 152 ng × h/mL) in rats. The P_app values of CAPE and CAPE-NO₂ were (4.86 ± 0.90) × 10^-6cm/s and (12.34 ± 1.6) × 10^-6cm/s, respectively. The accumulation of rhodamine 123 was increased by 1.3- to 1.9-fold and 1.4- to 2.3-fold in CAPE and CAPE-NO₂ groups after 1 h administration, respectively. However, CAPE and CAPE-NO₂ increased the P-gp levels by 2.1- and 1.7-fold, respectively.

CONCLUSION

The absorption of CAPE-NO₂ can be enhanced in rats and Caco-2 cells compared with CAPE. The two compounds are potential inhibitors of P-gp. The increased P-gp levels generated by CAPE and CAPE-NO₂ played a role as a defense mechanism by limiting intracellular xenobiotic levels.