Risk Assessment of Chlorogenic and Isochlorogenic Acids in Coffee By-Products

Evaluation of the effect of roasting and digestion on biological activity of compounds of coffee extracts - in vitro assessment of the bioavailability, cytoprotective properties and modulation of inflammatory response

Coffee is the most consumed beverage in the world. Consumption of phenolic compounds present in coffee protects the body against oxidative stress generation, inflammatory response, and cancer development. The aim of the study was evaluation of biological activity of coffee extracts (obtained from green, as well as light and dark roasted Robusta and Arabica beans) and isolated fractions on human colon adenocarcinoma Caco-2 cells, which are used as a cellular model of intestinal barrier in bioavailability studies. Additionally, impact of coffee phenolics on oxidative stress level and anti-inflammatory activity has been studied with RAW 264.7 macrophages used in immunomodulatory research. It was demonstrated that the coffee constituents protection against oxidative stress, lipotoxicity and secretion of proinflammatory mediators is correlated with the presence of mono- and dichlorogenic acids and roasting process. It was demonstrated that coffee phytochemicals can decrease cells proliferation and bind to topoisomerase IIα being a dietary tool in cancer prevention.

Potential Risk of Caffeoylquinic Acids, the Main Polyphenol Components in Coffee, on the Health of Piglets

As the main coffee polyphenols, caffeoylquinic acids (CQAs) are abundant in coffee-derived products and have the potential to act as novel feed additives for animals. However, research on the side effects of dietary CQAs supplementation is scarce, especially in young animals. Here, we explore the safety of CQAs derived from green coffee beans. Results showed that ingesting 50, 125, 250, and 500 mg/kg of dietary CQAs for 55 days is associated with greater final body weight, average daily gain, and feed efficiency in piglets compared with the control group (P < 0.05). CQAs also increased the apparent digestibility of dry matter, crude protein, and gross energy at a dose over 50 mg/kg (P < 0.05). Interestingly, CQAs supplementation with 500 mg/kg increased the white blood cell count (P < 0.05). Moreover, CQAs supplementation at a dose over 50 mg/kg decreased the serum total cholesterol concentration but increased the immunoglobulin M level in serum (P < 0.05). Importantly, CQAs supplementation had no side effects on organ histopathology and organ weight (P > 0.05). These results suggest that CQAs could serve as a secure and effective additive to improve growth performance without negatively affecting the organs of piglets.

Pharmacological profile of dicaffeoylquinic acids and their role in the treatment of respiratory diseases

Dicaffeoylquinic acids (DCQAs) are polyphenolic compounds found in various medicinal plants such as Echinacea species and Hedera helix, whose multi-constituent extracts are used worldwide to treat respiratory diseases. Besides triterpenes, saponins, alkamides, and other constituents, DCQAs are an important group of substances for the pharmacological activity of plant-derived extracts. Therefore, the pharmacological properties of DCQAs have been studied over the last decades, suggesting antioxidative, anti-inflammatory, antimicrobial, hypoglycaemic, cardiovascular protective, neuroprotective, and hepatoprotective effects. However, the beneficial pharmacological profile of DCQAs has not yet been linked to their use in treating respiratory diseases such as acute or even chronic bronchitis. The aim of this review was to assess the potential of DCQAs for respiratory indications based on published in vitro and in vivo pharmacological and pre-clinical data, with particular focus on antioxidative, anti-inflammatory, and respiratory-related effects such as antitussive or antispasmodic properties. A respective literature search revealed a large number of publications on the six DCQA isoforms. Based on this search, a focus was placed on 1,3-, 3,4-, 3,5-, and 4,5-DCQA, as the publications focused mainly on these isomers. Based on the available pre-clinical data, DCQAs trigger cellular mechanisms that are important in the treatment of respiratory diseases such as decreasing NF-κB activation, reducing oxidative stress, or activating the Nrf2 pathway. Taken together, these data suggest an essential role for DCQAs within herbal medicines used for the treatment of respiratory diseases and highlights the need for the identifications of DCQAs as lead substances within such extracts.

Neuroprotective role of chlorogenic acid against hippocampal neuroinflammation, oxidative stress, and apoptosis following acute seizures induced by pentylenetetrazole

This study investigated the neuroprotective effect of chlorogenic acid (CGA) on pentylenetetrazole (PTZ)-induced acute epileptic seizures in mice. Epileptic animals received CGA (200 mg/kg) or sodium valproate (standard antiepileptic agent, 200 mg/kg) for four weeks. Results revealed that pre-administration of CGA significantly reversed the behavioral changes following pentylenetetrazole (PTZ) injection. Further, CGA pre-treatment caused significant increases in acetylcholinesterase (AChE) activity and brain-derived neurotrophic factor (BDNF) levels, along with marked increases in dopamine, norepinephrine, and serotonin levels. Additionally, the increased antioxidant enzymes activities, along with higher glutathione (GSH) contents and upregulated nuclear factor erythroid 2-related factor 2 (Nrf2) gene expression, were indicative of a notable improvement in the cellular antioxidant defense in mice treated with CGA. These results were associated with lowered malondialdehyde (MDA) and nitric oxide (NO) levels. Moreover, epileptic mice that received CGA showed significant declines in the content of interleukin-1 beta (IL-1β), interleukin-6 (IL-6), tumor necrosis factor alpha (TNF-α), and nuclear factor kappa-B (NF-κB), besides downregulating inducible nitric oxide synthase (iNOS) expression. Remarkably, CGA counteracted hippocampal apoptosis by lessening the levels of pro-apoptotic biomarkers [Bcl-2-associated X protein (Bax) and caspase-3] and increasing the anti-apoptogenic marker level of B-cell lymphoma 2 (Bcl-2). The hippocampal histopathological findings corroborated the abovementioned changes. In sum, these findings suggest that CGA could mediate the neuroprotective effect against PTZ-induced epilepsy via modulation of neurotransmitters, oxidative damage, neuroinflammation, and apoptosis. CGA, therefore, could be considered a valuable antiepileptic therapeutic supplement.

Food Safety Assessment and Nutraceutical Outcomes of Dairy By-Products: Ovine Milk Whey as Wound Repair Enhancer on Injured Human Primary Gingival Fibroblasts

The valorization of milk whey appears to be a promising strategy for managing by-products from dairy food industries, which incur demanding economic costs for treatment and/or disposal. Thanks to its numerous bioactive components, whey is expected to be increasingly incorporated into foods in the future. We investigated the safety of ovine milk whey through in vitro experiments on human primary gingival fibroblast (HGF-1) proliferation and wound healing. Fibroblasts play a crucial role in the repair processes from the late inflammatory phase until the final stages. Cells treated with varying concentrations of ovine whey (0.01%, 0.1%, 1%, and 10%) were able to close wounds more rapidly than vehicle-treated cells. Time- and dose-dependent responses were observed in cell populations exposed to ovine whey. Specifically, wounds treated with 0.1% and 10% milk whey showed better migratory capabilities compared to those treated with 0.01% and 1% milk whey after 24 and 48 h. In addition, ovine milk whey stimulates extracellular matrix deposition, as evidenced by the increasing levels of CD44 antigen density evaluated through FACS analysis, as well as COL1A1 expression measured both via RT-qPCR and immunofluorescence. This phenomenon was particularly evident at concentrations of 0.01% and 10%. Ensuring quality and safety has become a major concern for health authorities in the food industry. Our findings suggest that ovine milk whey is safe and possesses regenerative properties. It facilitates tissue re-establishment following exposure to environmental stress, particularly accelerating gingival wound closure.

Potential Antioxidant and Anti-Inflammatory Properties of Polyphenolic Compounds from Cirsium japonicum Extract

Cirsium japonicum is a medicinal plant that has been used due to its beneficial properties. However, extensive information regarding its therapeutic potential is scarce in the scientific literature. The antioxidant and anti-inflammatory potential of polyphenols derived from the Cirsium japonicum extracts (CJE) was systematically analyzed. High-performance liquid chromatography (HPLC) with mass spectrometry (MS) was used to examine the compounds in CJE. A total of six peaks of polyphenol compounds were identified in the extract, and their MS data were also confirmed. These bioactive compounds were subjected to ultrafiltration with LC analysis to assess their potential for targeting cyclooxygenase-2 (COX2) and DPPH. The outcomes showed which primary compounds had the highest affinity for binding both COX2 and DPPH. This suggests that components that showed excellent binding ability to DPPH and COX2 can be considered significant active substances. Additionally, in vitro analysis of CJE was carried out in macrophage cells after inducing inflammation with lipopolysaccharide (LPS). As a result, it downregulated the expression of two critical pro-inflammatory cytokines, COX2 and inducible nitric oxide synthase (iNOS). In addition, we found a solid binding ability through the molecular docking analysis of the selected compounds with inflammatory mediators. In conclusion, we identified polyphenolic compounds in CJE extract and confirmed their potential antioxidant and anti-inflammatory effects. These results may provide primary data for the application of CJE in the food and pharmaceutical industries with further analysis.

Toll-like receptors in inflammatory bowel disease: A review of the role of phytochemicals

BACKGROUND

Inflammatory bowel disease (IBD) is a chronic inflammation within the gastrointestinal tract with a remarkable impact on patients' quality of life. Toll-like receptors (TLR), as a key contributor of immune system in inflammation, has a critical role in the pathogenesis of IBD and thus, can be a suitable target of therapeutic agents. Medicinal plants have long been considered as a source of bioactive agents for different diseases, including IBD.

PURPOSE

This review discusses current state of the art on the role of plant-derived compounds for the management of IBD with a focus on TLRs.

METHODS

Electronic database including PubMed, Web of Science, and Scopus were searched up to January 2023 and all studies in which anticolitis effects of a phytochemical was assessed via modulation of TLRs were considered.

RESULTS

Different categories of phytochemicals, including flavonoids, lignans, alkaloids, terpenes, saccharides, and saponins have demonstrated modulatory effects on TLR in different animal and cell models of bowel inflammation. Flavonoids were the most studied phytochemicals amongst others. Also, TLR4 was the most important type of TLRs which were modulated by phytochemicals. Other mechanisms such as inhibition of pro-inflammatory cytokines, nuclear factor-κB pathway, nitric oxide synthesis pathway, cyclooxygenase-2, lipid peroxidation, as well as induction of endogenous antioxidant defense mechanisms were also reported for phytochemicals in various IBD models.

CONCLUSION

Taken together, a growing body of pre-clinical evidence support the efficacy of herbal compounds for the treatment of IBD via modulation of TLRs. Future clinical studies are recommended to assess the safety and efficacy of these compounds in human.

Research Progress Regarding the Effect and Mechanism of Dietary Polyphenols in Liver Fibrosis

The development of liver fibrosis is a result of chronic liver injuries may progress to liver cirrhosis and liver cancer. In recent years, liver fibrosis has become a major global problem, and the incidence rate and mortality are increasing year by year. However, there are currently no approved treatments. Research on anti-liver-fibrosis drugs is a top priority. Dietary polyphenols, such as plant secondary metabolites, have remarkable abilities to reduce lipid metabolism, insulin resistance and inflammation, and are attracting more and more attention as potential drugs for the treatment of liver diseases. Gradually, dietary polyphenols are becoming the focus for providing an improvement in the treatment of liver fibrosis. The impact of dietary polyphenols on the composition of intestinal microbiota and the subsequent production of intestinal microbial metabolites has been observed to indirectly modulate signaling pathways in the liver, thereby exerting regulatory effects on liver disease. In conclusion, there is evidence that dietary polyphenols can be therapeutically useful in preventing and treating liver fibrosis, and we highlight new perspectives and key questions for future drug development.