Chlorogenic Acid: A Systematic Review on the Biological Functions, Mechanistic Actions, and Therapeutic Potentials.

Chlorogenic acid (CGA) is a type of polyphenol compound found in rich concentrations in many plants such as green coffee beans. As an active natural substance, CGA exerts diverse therapeutic effects in response to a variety of pathological challenges, particularly conditions associated with chronic metabolic diseases and age-related disorders. It shows multidimensional functions, including neuroprotection for neurodegenerative disorders and diabetic peripheral neuropathy, anti-inflammation, anti-oxidation, anti-pathogens, mitigation of cardiovascular disorders, skin diseases, diabetes mellitus, liver and kidney injuries, and anti-tumor activities. Mechanistically, its integrative functions act through the modulation of anti-inflammation/oxidation and metabolic homeostasis. It can thwart inflammatory constituents at multiple levels such as curtailing NF-kB pathways to neutralize primitive inflammatory factors, hindering inflammatory propagation, and alleviating inflammation-related tissue injury. It concurrently raises pivotal antioxidants by activating the Nrf2 pathway, thus scavenging excessive cellular free radicals. It elevates AMPK pathways for the maintenance and restoration of metabolic homeostasis of glucose and lipids. Additionally, CGA shows functions of neuromodulation by targeting neuroreceptors and ion channels. In this review, we systematically recapitulate CGA's pharmacological activities, medicinal properties, and mechanistic actions as a potential therapeutic agent. Further studies for defining its specific targeting molecules, improving its bioavailability, and validating its clinical efficacy are required to corroborate the therapeutic effects of CGA.

In Vitro Effects of Charged and Zwitterionic Liposomes on Human Spermatozoa and Supplementation with Liposomes and Chlorogenic Acid during Sperm Freezing.

Semen handling and cryopreservation induce oxidative stress that should be minimized. In this study, human semen was supplemented during cryopreservation with formulations of handmade liposomes and chlorogenic acid (CGA), an antioxidant compound. Zwitterionic (ZL), anionic (AL), and cationic (CL) liposomes were synthesized and characterized. Three aliquots of swim-up-selected sperm were incubated with ZL, AL, and CL (1:10,000), respectively. The percentages of sperm with progressive motility, high mitochondrial membrane potential (MMP; JC-1), double-stranded DNA (dsDNA acridine orange), and acrosome integrity (Pisum sativum agglutinin) were assessed. Then, human semen was frozen using both 1:10,000 ZL and CGA as follows: freezing medium/empty ZL (EL), freezing medium/empty ZL/CGA in the medium (CGA + EL), freezing medium/CGA loaded ZL (CGA), freezing medium (CTR). The same sperm endpoints were evaluated. ZL were the most tolerated and used for semen cryopreservation protocols. All the supplemented samples showed better endpoints versus CTR (p < 0.001). In particular, spermatozoa from the CGA and CGA + EL A samples showed increased motility, dsDNA, and acrosome integrity versus CTR and EL (p < 0.001; motility EL vs. CGA + EL p < 0.05). ZL and CGA can improve post-thaw sperm quality, acting on both cold shock effect management and oxidative stress. These findings open new perspectives on human and animal reproduction.

Chlorogenic acid prevents ovariectomized-induced bone loss by facilitating osteoblast functions and suppressing osteoclast formation.

Osteoporosis is a usual bone disease in aging populations, principally in postmenopausal women. Anti-resorptive and anabolic drugs have been applied to prevent and cure osteoporosis and are associated to a different of adverse effects. Du-Zhong is usually applied in Traditional Chinese Medicine to strengthen bone, regulate bone metabolism, and treat osteoporosis. Chlorogenic acid is a major polyphenol in Du-Zhong. In the current study, chlorogenic acid was found to enhance osteoblast proliferation and differentiation. Chlorogenic acid also inhibits the RANKL-induced osteoclastogenesis. Notably, ovariectomy significantly decreased bone volume and mechanical properties in the ovariectomized (OVX) rats. Administration of chlorogenic acid antagonized OVX-induced bone loss. Taken together, chlorogenic acid seems to be a hopeful molecule for the development of novel anti-osteoporosis treatment.

Protective Effect of Que Zui Tea on d-Galactose-Induced Oxidative Stress Damage in Mice via Regulating SIRT1/Nrf2 Signaling Pathway.

Que Zui tea (QT) is an important herbal tea in the diet of the 'Yi' people, an ethnic group in China, and it has shown significant antioxidant, anti-inflammatory, and hepatoprotective effects in vitro. This study aims to explore the protective effects of the aqueous-ethanol extract (QE) taken from QT against ᴅ-galactose (ᴅ-gal)-induced oxidative stress damage in mice and its potential mechanisms. QE was identified as UHPLC-HRMS/MS for its chemical composition and possible bioactive substances. Thus, QE is rich in phenolic and flavonoid compounds. Twelve compounds were identified, the main components of which were chlorogenic acid, quinic acid, and 6'-O-caffeoylarbutin. Histopathological and biochemical analysis revealed that QE significantly alleviated brain, liver, and kidney damage in ᴅ-gal-treated mice. Moreover, QE remarkably attenuated oxidative stress by activating the Nrf2/HO-1 pathway to increase the expression of antioxidant indexes, including GSH, GSH-Px, CAT, SOD, and T-AOC. In addition, QE administration could inhibit the IL-1ß and IL-6 levels, which suppress the inflammatory response. QE could noticeably alleviate apoptosis by inhibiting the expressions of Caspase-3 and Bax proteins in the brains, livers, and kidneys of mice. The anti-apoptosis mechanism may be related to the upregulation of the SIRT1 protein and the downregulation of the p53 protein induced by QE in the brain, liver, and kidney tissues of mice. Molecular docking analysis demonstrated that the main components of QE, 6'-O-caffeoylarbutin, chlorogenic acid, quinic acid, and robustaside A, had good binding ability with Nrf2 and SIRT1 proteins. The present study indicated that QE could alleviate ᴅ-gal-induced brain, liver and kidney damage in mice by inhibiting the oxidative stress and cell apoptosis; additionally, the potential mechanism may be associated with the SIRT1/Nrf2 signaling pathway.

Exogenous chlorogenic acid inhibits quality deterioration in fresh-cut potato slices.

Fresh-cut potatoes are prone to surface browning and physiological degradation. Chlorogenic acid (CGA), a natural phenolic antioxidant, has demonstrated preservative properties in various postharvest products. However, the underlying mechanisms of its application on maintaining quality remain unclear. Therefore, the effect of exogenous CGA treatment on quality deterioration of potato slices and the mechanisms involved were investigated. Results revealed CGA treatment retarded the browning coloration, suppressed microbial growth and inhibited the declines in starch, and ascorbic acid contents in potato slices. Meanwhile, the treatment activated the phenylpropanoid pathway but decreased the activities of phenolic decomposition-related enzymes such as polyphenol oxidase (PPO) and tyrosinase and downregulated StPPO expression. Moreover, the treated slices exhibited reduced accumulation of reactive oxygen species and increased activity of antioxidant enzymes. Additionally, they displayed enhanced 2,2-diphenyl-1-picrylhydrazyl radicals scavenging capacity and higher ATP levels. Therefore, these findings indicated that CGA treatment was effective for quality maintenance and antioxidant capacity enhancement in fresh-cut potatoes, thereby providing potential strategies for the preservation and processing of fresh-cut produce.

RNA-seq analysis of chlorogenic acid intervention in duck embryo fibroblasts infected with duck plague virus.

INTRODUCTION: Chlorogenic acid, the primary active component in Chinese medicines like honeysuckle, exhibits anti-inflammatory and antiviral effects. It has been demonstrated that chlorogenic acid effectively prevents and treats Duck enteritis virus (DEV) infection. This study aims to further elucidate the mechanism by which chlorogenic acid prevents DEV infection. METHODS: Duck embryo fibroblast (DEF) cells were pre-treated with chlorogenic acid before being infected with DEV. Cell samples were collected at different time points for transcriptomic sequencing, while qPCR was used to detect the proliferation of DEV. Additionally, 30-day-old ducks were treated with chlorogenic acid, and their lymphoid organs were harvested for histopathological sections to observe pathological damage. The proliferation of DEV in the lymphoid organs was also detected using qPCR Based on the transcriptomic sequencing results, NF-κB1 gene was silenced by RNAi technology to analyze the effect of NF-κB1 gene on DEV proliferation. RESULTS: Compared to the viral infection group, DEF cells in the chlorogenic acid intervention group exhibited significantly reduced DEV load (P < 0.05). Transcriptomic sequencing results suggested that chlorogenic acid inhibited DEV proliferation in DEF cells by regulating NF-κB signaling pathway. The results of RNAi silencing suggested that in the three treatment groups, compared with the DEV experimental group, there was no significant difference in the effect of pre-transfection after transfection on DEV proliferation, while both the pre-transfection after transfection and the simultaneous transfection group showed significant inhibition on DEV proliferation Furthermore, compared to the virus infection group, ducks in the chlorogenic acid intervention group showed significantly decreased DEV load in their lymphoid organs (P < 0.05), along with alleviated pathological damage such as nuclear pyretosis and nuclear fragmentation. CONCLUSIONS: Chlorogenic acid effectively inhibits DEV proliferation in DEF and duck lymphatic organs, mitigates viral-induced pathological damage, and provides a theoretical basis for screening targeted drugs against DEV.

Chlorogenic Acid Attenuates Isoproterenol Hydrochloride-Induced Cardiac Hypertrophy in AC16 Cells by Inhibiting the Wnt/ß-Catenin Signaling Pathway.

Cardiac hypertrophy (CH) is an important characteristic in heart failure development. Chlorogenic acid (CGA), a crucial bioactive compound from honeysuckle, is reported to protect against CH. However, its underlying mechanism of action remains incompletely elucidated. Therefore, this study aimed to explore the mechanism underlying the protective effect of CGA on CH. This study established a CH model by stimulating AC16 cells with isoproterenol (Iso). The observed significant decrease in cell surface area, evaluated through fluorescence staining, along with the downregulation of CH-related markers, including atrial natriuretic peptide (ANP), brain natriuretic peptide (BNP), and ß-myosin heavy chain (ß-MHC) at both mRNA and protein levels, provide compelling evidence of the protective effect of CGA against isoproterenol-induced CH. Mechanistically, CGA induced the expression of glycogen synthase kinase 3ß (GSK-3ß) while concurrently attenuating the expression of the core protein ß-catenin in the Wnt/ß-catenin signaling pathway. Furthermore, the experiment utilized the Wnt signaling activator IM-12 to observe its ability to modulate the impact of CGA pretreatment on the development of CH. Using the Gene Expression Omnibus (GEO) database combined with online platforms and tools, this study identified Wnt-related genes influenced by CGA in hypertrophic cardiomyopathy (HCM) and further validated the correlation between CGA and the Wnt/ß-catenin signaling pathway in CH. This result provides new insights into the molecular mechanisms underlying the protective effect of CGA against CH, indicating CGA as a promising candidate for the prevention and treatment of heart diseases.

Modulation of thioredoxin by chlorogenic acid in an ischemic stroke model and glutamate-exposed neurons.

Ischemic stroke increases the production of reactive oxygen species (ROS), which can eventually lead to neuronal death. Thioredoxin is a small reductase protein that acts as an eliminator of ROS and protects neurons from brain damage. Chlorogenic acid is known as a phenolic compound that has a neuroprotective effect. We investigated the change of thioredoxin expression by chlorogenic acid in a middle cerebral artery occlusion (MCAO) animal model. Adult rats were injected intraperitoneally with phosphate buffered saline or chlorogenic acid (30 mg/kg) 2 h after MCAO. MCAO damage induced neurological defects and increased ROS and lipid peroxidation levels, however, chlorogenic acid mitigated these changes. MCAO damage reduced thioredoxin expression, which was mitigated by chlorogenic acid treatment. The interaction between thioredoxin and apoptosis signal-regulating kinase 1 (ASK1) was decreased in MCAO animals, chlorogenic acid treatment prevented this decrease. In cultured neurons, chlorogenic acid dose-dependently attenuated glutamate-induced decreases in cell viability and thioredoxin expression. Glutamate toxicity downregulated bcl-2 and upregulated bax, cytochrome c, and caspase-3, however, chlorogenic acid attenuated these changes. The mitigating effect of chlorogenic acid was lower in thioredoxin siRNA-transfected cells than in non-transfected cells. These results provide evidence that chlorogenic acid exerts potent antioxidant and neuroprotective effects through regulation of thioredoxin and modulation of ASK1 and thioredoxin binding in ischemic brain injury. These findings indicate that chlorogenic acid exerts a neuroprotective effect by regulating thioredoxin expression in cerebral ischemia and glutamate exposure conditions.

Antioxidant, antimicrobial and healing properties of an extract from coffee pulp for the development of a phytocosmetic.

Consumer demand for natural, chemical-free products has grown. Food industry residues, like coffee pulp, rich in caffeine, chlorogenic acid and phenolic compounds, offer potential for pharmaceutical and cosmetic applications due to their antioxidant, anti-inflammatory, and antibacterial properties. Therefore, the objective of this work was to develop a phytocosmetic only with natural products containing coffee pulp extract as active pharmaceutical ingredient with antioxidant, antimicrobial and healing activity. Eight samples from Coffea arabica and Coffea canephora Pierre were analyzed for caffeine, chlorogenic acid, phenolic compounds, tannins, flavonoids, cytotoxicity, antibacterial activity, and healing potential. The Robusta IAC-extract had the greatest prominence with 192.92 µg/mL of chlorogenic acid, 58.98 ± 2.88 mg GAE/g sample in the FRAP test, 79.53 ± 5.61 mg GAE/g sample in the test of total phenolics, was not cytotoxic, and MIC 3 mg/mL against Staphylococcus aureus. This extract was incorporated into a stable formulation and preferred by 88% of volunteers. At last, a scratch assay exhibited the formulation promoted cell migration after 24 h, therefore, increased scratch retraction. In this way, it was possible to develop a phytocosmetic with the coffee pulp that showed desirable antioxidant, antimicrobial and healing properties.

Pyrosequencing analysis of bacterial community changes in dental unit waterlines after chlorogenic acid treatment.

Introduction: The contamination of dental unit waterlines (DUWLs) poses a significant risk of cross-infection in dentistry. Although chemical disinfectants have been effective in reducing number of bacteria, they do have limitations. Methods: This study aimed to investigate the potential of chlorogenic acid, a natural substance with broadspectrum antibacterial properties, for treating DUWLs. Over a period of three months, we analyzed the microbial communities in 149 DUWLs samples collected from 5 dental units using high-throughput pyrophosphate sequencing. Results: The results revealed that chlorogenic acid treatment had a significant impact on the microbial community profile in the DUWLs, with the most significant changes occurring within the first 15 days and stabilization observed in the last 30 days. The predominant genera detected in the samples were Bacteroides, Lactobacillus, Streptococcus, Methylobacterium, and Phreatobacter. Additionally, the relative abundance of certain beneficial bacteria, such as Alloprevotella, Roseburia, and Blautia, increased, while the presence of opportunistic pathogens like Mycobacteria significantly decreased. The functional prediction analysis using the KEGG database indicated a decrease in the pathogenicity of the bacterial community in the DUWLs following chlorogenic acid treatment. Discussion: This study introduces a novel approach for the prevention and treatment of infections associated with dental care.

Chlorogenic Acid Inhibits Progressive Pulmonary Fibrosis in a Diabetic Rat Model.

Background: Chlorogenic acid (CGA) is known to have antifibrotic and hypoglycemic effects and may play a role in preventing diabetes-induced pulmonary fibrosis. This study aimed to determine the effect and optimum dose of CGA on diabetes-induced pulmonary fibrosis. Methods: Thirty Wistar rats (two-month-old, 150-200 grams) were randomly divided into six groups, namely control, six weeks diabetes mellitus (DM1), eight weeks DM (DM2), and three DM2 groups (CGA1, CGA2, and CGA3) who received CGA doses of 12.5, 25, and 50 mg/Kg BW, respectively. After six weeks, CGA was administered intraperitoneally for 14 consecutive days. Lung tissues were taken for TGF-ß1, CTGF, SMAD7, Collagen-1, and α-SMA mRNA expression analysis and paraffin embedding. Data were analyzed using one-way ANOVA and the Kruskal-Wallis test. P<0.05 was considered statistically significant. Results: TGF-ß1 expression in the CGA1 group (1.01±0.10) was lower than the DM1 (1.33±0.25, P=0.05) and DM2 (1.33±0.20, P=0.021) groups. α-SMA expression in the CGA1 group (median 0.60, IQR: 0.34-0.64) was lower than the DM1 (median 0.44, IQR: 0.42-0.80) and DM2 (median 0.76, IQR: 0.66-1.10) groups. Collagen-1 expression in the CGA1 group (0.75±0.13) was lower than the DM1 (P=0.24) and DM2 (P=0.26) groups, but not statistically significant. CTGF expression in CGA groups was lower than the DM groups (P=0.088), but not statistically significant. There was an increase in SMAD7 expression in CGA groups (P=0.286). Histological analysis showed fibrosis improvement in the CGA1 group compared to the DM groups. Conclusion: CGA (12.5 mg/Kg BW) inhibited the expression of profibrotic factors and increased antifibrotic factors in DM-induced rats.

Chlorogenic acid inhibits macrophage PANoptosis induced by cefotaxime-resistant Escherichia coli.

Antibiotics are commonly used in clinical practice to treat bacterial infections. Due to the abuse of antibiotics, the emergence of drug-resistant strains, such as cefotaxime sodium-resistant Escherichia coli (CSR-EC), has aggravated the treatment of diseases caused by bacterial infections in the clinic. Therefore, discovering new drug candidates with unique mechanisms of action is imperative. Chlorogenic acid (CGA) is an active component of Yinhua Pinggan Granule, which has antioxidant and anti-inflammatory effects. We chose the CGA to explore its effects on PANoptosis in cultured macrophages infected with CSR-EC. In this study, we explored the protective impact of CGA on macrophage cell damage generated by CSR-EC infection and the potential molecular mechanistic consequences of post-infection therapy with CGA on the PANoptosis pathway. Our findings demonstrated that during CSR-EC-induced macrophage infection, CGA dramatically increased cell survival. CGA can inhibit pro-inflammatory cytokine expression of IL-1ß, IL-18, TNF-α, and IL-6. CGA decreased ROS generation and increased Nrf-2 expression at the gene and protein levels to lessen the cell damage and death brought on by CSR-EC infection. Additionally, we discovered that the proteins Caspase-3, Caspase-7, Caspase-8, Caspase-1, GSDMD, NLRP-3, RIPK-3, and MLKL were all inhibited by CGA. In summary, our research suggests that CGA is a contender for reducing lesions brought on by CSR-EC infections and that it can work in concert with antibiotics to treat CSR-EC infections clinically. However, further research on its mechanism of action is still needed.

Clinical Evaluation of a Novel, Patented Green Coffee Bean Extract (GCB70®), Enriched in 70% Chlorogenic Acid, in Overweight Individuals.

OBJECTIVE: Obesity and overweight are challenging health problems of the millennium that lead to diabetes, hypertension, dyslipidemia, nonalcoholic fatty liver disease (NAFLD), and atherosclerosis. Green coffee bean exhibited significant promise in healthy weight management, potentiating glucose-insulin sensitization and supporting liver health. The safety and efficacy of a novel, patented water-soluble green coffee bean extract (GCB70® enriched in 70% total chlorogenic acid and <1% caffeine) was investigated in 105 participants for 12 consecutive weeks. An institutional review board and Drugs Controller General (India) (DCGI) approvals were obtained, and the study was registered at ClinicalTrials.gov. METHOD: Body weight, body mass index (BMI), waist circumference, lipid profile, plasma leptin, glycosylated hemoglobin (HbA1c), and total blood chemistry were assessed over a period of 12 weeks of treatment. Safety was affirmed. RESULTS: GCB70 (500 mg BID) supplementation significantly reduced body weight (approximately 6%; p = 0.000**) in approximately 97% of the study population. About a 5.65% statistically significant reduction (p = 0.000**) in BMI was observed in 96% of the study volunteers. Waist circumference was significantly reduced by 6.77% and 6.62% in 98% of the male and female participants, respectively. Plasma leptin levels decreased by 13.6% in 99% of the study population as compared to the baseline value. Upon completion of 12 weeks' treatment, fasting glucose levels decreased by 13.05% (p = 0.000**) in 79% of the study population. There was a statistically significant decrease in HbA1c levels in both male and female participants (p = 0.000**), while 86.7% of the study participants showed a statistically significant decrease in thyroid-stimulating hormone (TSH) levels (p = 0.000**). The mean decrease in TSH levels on completion of the treatment was 14.07% in the study population as compared to baseline levels. Total blood chemistry analysis exhibited broad-spectrum safety. CONCLUSIONS: This investigation demonstrated that GCB70 is safe and efficacious in healthy weight management.

Modulation of apoptosis and Inflammasome activation in chondrocytes: co-regulatory role of Chlorogenic acid.

BACKGROUND: The B-cell lymphoma 2 (Bcl-2) protein regulates programmed cell death throughout the disease conditions by upholding apoptotic pathways. However, the mechanism by which it's expressed in chondrocytes still needs to be studied in chondrocyte-related disorders. Additionally, exploring the potential therapeutic role of Chlorogenic acid (CGA) in confluence with Bcl-2 modulation is of significant interest. METHODS: In vivo and in vitro studies were performed according to our previous methodologies. The chondrocytes were cultured in specific growth media under standard conditions after expression verification of different microRNAs through high-throughput sequencing and verification of Bcl-2 involvement in tibial growth plates. The effect of Bcl-2 expression was investigated by transfecting chondrocytes with miR-460a, siRNA, and their negative controls alone or in combination with CGA. The RNA was extracted and subjected to a reverse transcription-quantitative polymerase chain reaction (RT-qPCR). Western blot analysis and immunofluorescence assays were performed to visualize the intracellular localization of Bcl-2 and associated proteins related to apoptotic and inflammasome pathways. Moreover, apoptosis through flow cytometry was also performed to understand the modulation of concerning pathways. RESULTS: The suppression of Bcl-2 induced higher apoptosis and mitochondrial dysfunction, leading to IL-1ß maturation and affecting the inflammasome during chondrocyte proliferation. Conversely, overexpression attenuated the activation, as evidenced by reduced caspase activity and IL-1ß maturation. In parallel, CGA successfully reduced siRNA-induced apoptosis by decreasing Cytochrome C (Cyto C) release from the mitochondria to the cytoplasm, which in turn decreased Caspase-3 and Caspase-7 cleavage with Bcl-2-associated X protein (Bax). Furthermore, siBcl-2 transfection and CGA therapy increased chondrocyte proliferation and survival. The CGA also showed a promising approach to maintaining chondrocyte viability by inhibiting siRNA-induced apoptosis. CONCLUSIONS: Targeting Bcl-2-mediated regulation might be a possible treatment for chondrocyte-related conditions. Moreover, these results add knowledge of the complicated processes underlying chondrocyte function and the pathophysiology of related diseases, highlighting the significance of target specific therapies. Video Abstract.

Antioxidant potential of chlorogenic acid in Age-Related eye diseases.

Oxidative stress is an important mechanism of aging, and in turn, aging can also aggravate oxidative stress, which leads to a vicious cycle. In the process of the brain converting light into visual signals, the eye is stimulated by harmful blue-light radiation directly. Thus, the eye is especially vulnerable to oxidative stress and becomes one of the organs most seriously involved during the aging process. Cataracts, age-related macular degeneration (AMD), glaucoma, diabetic retinopathy (DR), and dry eye are inextricably linked to the aging process and oxidative stress. Chlorogenic acid (CGA) has been demonstrated to have antioxidant and anti-inflammatory activities, and its validity has been established experimentally in numerous fields, including cardiovascular disease, metabolic disorders, cancers, and other chronic diseases. There has previously been evidence of CGA's therapeutic effect in the field of ophthalmopathy. Considering that many ophthalmic drugs lead to systemic side effects, CGA may act as a natural exogenous antioxidant for patients to take regularly, controlling their condition while minimizing side effects. In this paper, in vitro and in vivo studies of CGA in the treatment of age-related eye diseases are reviewed, and the prospects of CGA's antioxidant application for the eye are discussed. The aim of this review is to summarize the relevant knowledge and provide theoretical support for future research.

Chlorogenic acid improves common carp (Cyprinus carpio) liver and intestinal health through Keap-1/Nrf2 and NF-κB signaling pathways: Growth performance, immune response and antioxidant capacity.

In this experiment, we investigated the effects of adding chlorogenic acid (CGA) to the diet on growth performance, immune function, inflammation response, antioxidant capacity and its related mechanisms of common carp (Cyprinus carpio). A total of 600 fish were selected and randomly divided into five treatment groups and fed with CGA containing 0 mg/kg (CK), 100 mg/kg (L100), 200 mg/kg (L200), 400 mg/kg (L400) and 800 mg/kg (L800) for 56 days. The results of the experiment were as follows: addition of CGA significantly increased the WGR, SGR, FER, and PER of common carp (P < 0.05). The addition of 400-800 mg/kg of CGA significantly increased the serum levels of LZM, AKP activity, C3 and C4 concentration, and increased immune function of common carp (P < 0.05). Regarding antioxidant enzyme activities, adding CGA significantly increased SOD, CAT, and GsH-Px activities, while decreasing MDA content (P < 0.05). Compared with the CK group, the mRNA expression levels of NF-κB, TNF-α, and IL-1ß were decreased. The IL-10 and TGF-ß were increased in the liver and intestines of the CGA supplemented group. Meanwhile, the addition of CGA also significantly up-regulated the mRNA expression levels of Nrf2, HO-1, SOD, CAT, and GPX (P < 0.05). CGA also positively contributed to the development of the carp intestinal tract, as demonstrated by decreased serum levels of DAO, D-LA, and ET-1. And the mucosal fold height was increased significantly with increasing levels of CGA. In conclusion, the addition of CGA in the feed can enhance the growth performance, immune function and antioxidant capacity of common carp, and improve the health of the intestine and liver. According to the results of this experiment, the optimal addition amount in common carp diets was 400 mg/kg.

Chlorogenic Acid Inhibits Proliferation, Migration and Invasion of Pancreatic Cancer Cells via AKT/GSK-3ß/ß-catenin Signaling Pathway.

BACKGROUND: Chlorogenic acid (CA, United States Patent No. 10772340), a natural biologically active food ingredient, displays potent antitumor activity against a variety of cancer cells. However, the mechanism underlying its anticancer effect is not well elucidated. OBJECTIVE: In the present study, we hope to dissect the mechanism underlying the anticancer effects of CA in pancreatic cancer cells. METHODS: The cytotoxicity of CA in pancreatic cancer cells was determined by MTT assay. Flow cytometry was performed to evaluate the cells apoptosis, while a clonogenic assay was carried out to check the colony formation of cancer cells. Transwell assay was performed to assess the cells migration and invasion. The protein expression of AKT/GSK-3ß/ß-catenin signaling pathway was detected by Western Blot. RESULTS: Our data indicated that CA inhibited the proliferation of PANC-28 and PANC-1 cells in a dose and time-dependent manner. CA was able to inhibit colony formation, migration, and invasion ability and trigger apoptosis in PANC-28 and PANC-1 cells. Further study showed that CA down-regulated the expression of AKT, p-AKT(Thr308), p-GSK-3ß(Ser9), ß-catenin, N-cadherin, and vimentin while enhancing the expression of cleaved-caspase 3 and cleaved-caspase 7 in PANC-28 and PANC-1 cells. CONCLUSION: Our study provides significant evidence that CA is able to inhibit the growth of pancreatic cancer via the AKT/GSK-3ß/ß-catenin signaling pathway.

DNA Mutagenicity of Hydroxyhydroquinone in Roasted Coffee Products and Its Suppression by Chlorogenic Acid, a Coffee Polyphenol, in Oxidative-Damage-Sensitive SAMP8 Mice.

Hydroxyhydroquinone (HHQ) is an oxidative component produced by roasting coffee beans and has been reported to generate relatively large amounts of reactive oxygen species (ROS). In this study, we used senescence-accelerated mouse prone 8 (SAMP8) mice to determine whether HHQ consumption increases oxidative-stress-induced injury, because in SAMP8 mice, the activity of 8-oxoguanine DNA glycosylase 1, which repairs oxidative modifications in DNA, is decreased. The results showed that two out of twelve (16.7%) HHQ-treated mice presented polyuria and glucosuria around 2 months after the start of treatment, indicating that HHQ may act as a mutagen against SAMP8 mice, which is sensitive to oxidative damage. No abnormalities were observed in the chlorogenic acid (coffee polyphenol, CPP)-treated group. The concentration of hydrogen peroxide in the serum of SAMP8 mice was significantly higher than that in SAMR1 (senescence-resistant) control mice, and the concentration was further increased in the HHQ-treated group. CPP, when coexisting with HHQ at the rate contained in roasted coffee, decreased the amount of hydrogen peroxide in the serum of SAMP8 mice. Although CPP can act both oxidatively and antioxidatively as a polyphenol, CPP acts more antioxidatively when coexisting with HHQ. Thus, the oxidative effect of HHQ was shown to be counteracted by CPP.

Cancer Differentiation Inducer Chlorogenic Acid Suppresses PD-L1 Expression and Boosts Antitumor Immunity of PD-1 Antibody.

As immune checkpoint inhibitors have shown good clinical efficacy, immune checkpoint blockade has become a vital strategy in cancer therapy. However, approximately only 12.5% patients experience benefits from immunotherapy. Herein, we identified the cancer differentiation inducer chlorogenic acid (CGA, now in the phase II clinical trial in China for glioma treatment) to be a small-molecular immune checkpoint inhibitor that boosted the antitumor effects of the anti-PD-1 antibody. CGA suppressed the expression of PD-L1 induced by interferon-γ in tumor cell culture through inhibition of the p-STAT1-IRF1 pathway and enhanced activity of activated T-cells. In two murine tumor xenografts, combination therapy of CGA with anti-PD-1 antibody decreased the expression of PD-L1 and IRF1 and increased the inhibitory effect of the anti-PD-1 antibody on tumor growth. Particularly, the activity of tumor infiltrated T cells was enhanced by CGA. CGA improved the gene expression of granzymes in tumor-infiltrated immune cells. In conclusion, through induction of differentiation, CGA appeared to suppress the expression of PD-L1 on cancer cells, effectively promoting infiltrated T cells in the tumor and boosting the antitumor effect of the anti-PD-1 antibody. Thus, CGA might serve as a promising agent to enhance anticancer immunotherapy if combined with anti-PD-1 antibodies.

Analysis of Polyphenol Extract from Hazel Leaf and Ameliorative Efficacy and Mechanism against Hyperuricemia Zebrafish Model via Network Pharmacology and Molecular Docking.

Hazel leaf, a by-product of hazelnuts, is commonly used in traditional folk medicine in Portugal, Sweden, Iran and other regions for properties such as vascular protection, anti-bleeding, anti-edema, anti-infection, and pain relief. Based on our previous studies, the polyphenol extract from hazel leaf was identified and quantified via HPLC fingerprint. The contents of nine compounds including kaempferol, chlorogenic acid, myricetin, caffeic acid, p-coumaric acid, resveratrol, luteolin, gallic acid and ellagic acid in hazel leaf polyphenol extract (ZP) were preliminary calculated, among which kaempferol was the highest with 221.99 mg/g, followed by chlorogenic acid with 8.23 mg/g. The inhibition of ZP on α-glucosidase and xanthine oxidase activities was determined via the chemical method, and the inhibition on xanthine oxidase was better. Then, the effect of ZP on hyperuricemia zebrafish was investigated. It was found that ZP obviously reduced the levels of uric acid, xanthine oxidase, urea nitrogen and creatinine, and up-regulated the expression ofOAT1 and HPRT genes in hyperuricemia zebrafish. Finally, the targeted network pharmacological analysis and molecular docking of nine polyphenol compounds were performed to search for relevant mechanisms for alleviating hyperuricemia. These results will provide a valuable basis for the development and application of hazel leaf polyphenols as functional ingredients.