In Vitro Study of the Differential Anti-Inflammatory Activity of Dietary Phytochemicals upon Human Macrophage-like Cells as a Previous Step for Dietary Intervention

Chronic inflammatory diseases pose a substantial health challenge globally, significantly contributing to morbidity and mortality. Addressing this issue requires the use of effective anti-inflammatory strategies with fewer side effects than those provoked by currently used drugs. In this study, a range of phytochemicals (phenolic di-caffeoylquinic acid (Di-CQA), flavonoid cyanidin-3,5-diglucoside (Cy3,5DiG), aromatic isothiocyanate sinalbin (SNB) and aliphatic isothiocyanate sulforaphane (SFN)) sourced from vegetables and fruits underwent assessment for their potential anti-inflammatory activity. An in vitro model of human macrophage-like cells treated with a low dose of LPS to obtain a low degree of inflammation that emulates a chronic inflammation scenario revealed promising results. Cell viability and production of the key pro-inflammatory cytokines were assessed in the presence of various phytochemicals. The compounds Di-CQA and Cy-3,5-DiG, within low physiologically relevant doses, demonstrated notable anti-inflammatory effects by significantly reducing the production of key pro-inflammatory cytokines TNF-α and IL-6 without affecting cell viability. These findings underscore the potential of plant-derived bioactive compounds as valuable contributors to the prevention or treatment of chronic inflammatory diseases. These results suggest that these compounds, whether used individually or as part of natural mixtures, hold promise for their inclusion in nutritional interventions designed to mitigate inflammation in associated pathologies.

Current Knowledge Regarding Pharmacological Profile and Chemical Constituents of Gynura procumbens

Gynura procumbens (Lour.) Merr. is a well-known plant used in the folkloric medicine in tropical Asian countries. The plant is prevalently employed by traditional healers in the treatment of diabetes, cancer, hypertension, inflammation, fever and skin disorders. Several scientific studies reported that, Gynura procumbens possesses considerable therapeutic value for the development of emerging treatment options. The diverse pharmacological effects of this plant are attributed to its vast phytoconstituent content. Different chemical classes including alkaloids, flavonoids, phenolics, steroids, proteins and polysaccharides have been isolated from this plant. In this review, we tried to explore the different aspects of Gynura procumbens as an established medicinal plant. The data gathered here give an indication that the plant Gynura procumbens is a good natural source of chemical compounds with different types of pharmacological actions and these chemical compounds can be used as model for the development of de novo therapeutic agents.

Bacitracin and Rutin Regulate Tissue Factor Production in Inflammatory Monocytes and Acute Myeloid Leukemia Blasts

Simple Summary

Aberrant tissue factor (TF) expression by transformed myeloblasts and inflammatory monocytes contributes to coagulation activation in acute myeloid leukemia (AML). TF procoagulant activity (PCA) is regulated by protein disulfide isomerase (PDI), an oxidoreductase with chaperone activity, but its specific role in AML-associated TF biology is unclear. Here, we provide novel mechanistic insights into this interrelation. We show that bacitracin and rutin, two pan-inhibitors of the PDI family, prevent lipopolysaccharide (LPS)-induced monocyte TF production under inflammatory conditions and constitutive TF expression by THP1 cells and AML blasts, thus exerting promising anticoagulant activity. Downregulation of the TF protein was mainly restricted to its non-coagulant, cryptic pool and was at least partially regulated on the mRNA level in LPS-stimulated monocytes. Collectively, our study indicates a complex role of thiol isomerases in the regulation of myeloid TF PCA, with the most abundant PDI being a promising therapeutic target in the management of AML-associated coagulopathies.

Abstract

Aberrant expression of tissue factor (TF) by transformed myeloblasts and inflammatory monocytes drives coagulation activation in acute myeloid leukemia (AML). Although regulation of TF procoagulant activity (PCA) involves thiol-disulfide exchange reactions, the specific role of protein disulfide isomerase (PDI) and other thiol isomerases in AML-associated TF biology is unclear. THP1 cells and peripheral blood mononuclear cells (PBMCs) from healthy controls or AML patients were analyzed for thiol isomerase-dependent TF production under various experimental conditions. Total cellular and membrane TF antigen, TF PCA and TF mRNA were analyzed by ELISA, flow cytometry, clotting or Xa generation assay and qPCR, respectively. PBMCs and THP1 cells showed significant insulin reductase activity, which was inhibited by bacitracin or rutin. Co-incubation with these thiol isomerase inhibitors prevented LPS-induced TF production by CD14-positive monocytes and constitutive TF expression by THP1 cells and AML blasts. Downregulation of the TF antigen was mainly restricted to the cryptic pool of TF, efficiently preventing phosphatidylserine-dependent TF activation by daunorubicin, and at least partially regulated on the mRNA level in LPS-stimulated monocytes. Our study thus delineates a complex role of thiol isomerases in the regulation of myeloid TF PCA, with PDI being a promising therapeutic target in the management of AML-associated coagulopathies.

Antioxidant and Anti-Inflammatory Effects of Genus Gynura: A Systematic Review

Background: Gynura species have been used traditionally to treat various ailments, such as fever, pain, and to control blood glucose level. This systematic review critically discusses studies regarding Gynura species that exhibited antioxidant and anti-inflammatory effects, thus providing perspectives and instructions for future research of the plants as a potential source of new dietary supplements or medicinal agents. Methods: A literature search from internet databases of PubMed, Scopus, Science Direct, e-theses Online Service, and ProQuest was carried out using a combination of keywords such as "Gynura," "antioxidant," "anti-inflammatory," or other related words. Research articles were included in this study if they were experimental (in vitro and in vivo) or clinical studies on the antioxidant or anti-inflammatory effects of Gynura species and if they were articles published in English. Results: Altogether, 27 studies on antioxidant and anti-inflammatory effects of Gynura species were selected. The antioxidant effects of Gynura species were manifested by inhibition of reactive oxygen species production and lipid peroxidation, modulation of glutathione-related parameters, and enzymatic antioxidant production or activities. The anti-inflammatory effects of Gynura species were through the modulation of inflammatory cytokine production, inhibition of prostaglandin E₂ and nitric oxide production, cellular inflammatory-related parameters, and inflammation in animal models. The potential anti-inflammatory signaling pathways modulated by Gynura species are glycogen synthase kinase-3, nuclear factor erythroid 2-related factor 2, PPARγ, MAPK, NF-κB, and PI3K/Akt. However, most reports on antioxidant and anti-inflammatory effects of the plants were on crude extracts, and the chemical constituents contributing to bioactivities were not clearly understood. There is a variation in quality of studies in terms of design, conduct, and interpretation, and in-depth studies on the underlying mechanisms involved in antioxidant and anti-inflammatory effects of the plants are in demand. Moreover, there is limited clinical study on antioxidant and anti-inflammatory effects of Gynura species. Conclusion: This review highlighted antioxidant and anti-inflammatory effects of genus Gynura and supported their traditional uses to treat oxidative stress and inflammatory-related diseases. This review is expected to catalyze further studies on genus Gynura. However, extensive preclinical data need to be generated from toxicity and pharmacokinetic studies before clinical studies can be pursued for their development into clinical medicines to treat oxidative stress and inflammatory conditions.

Plant-Based Phytochemicals as Possible Alternative to Antibiotics in Combating Bacterial Drug Resistance

The unprecedented use of antibiotics that led to development of resistance affect human health worldwide. Prescription of antibiotics imprudently and irrationally in different diseases progressed with the acquisition and as such development of antibiotic resistant microbes that led to the resurgence of pathogenic strains harboring enhanced armors against existing therapeutics. Compromised the treatment regime of a broad range of antibiotics, rise in resistance has threatened human health and increased the treatment cost of diseases. Diverse on metabolic, genetic and physiological fronts, rapid progression of resistant microbes and the lack of a strategic management plan have led researchers to consider plant-derived substances (PDS) as alternative or in complementing antibiotics against the diseases. Considering the quantitative characteristics of plant constituents that attribute health beneficial effects, analytical procedures for their isolation, characterization and phytochemical testing for elucidating ethnopharmacological effects has being worked out for employment in the treatment of different diseases. With an immense potential to combat bacterial infections, PDSs such as polyphenols, alkaloids and tannins, present a great potential for use, either as antimicrobials or as antibiotic resistance modifiers. The present study focuses on the mechanisms by which PDSs help overcome the surge in resistance, approaches for screening different phytochemicals, methods employed in the identification of bioactive components and their testing and strategies that could be adopted for counteracting the lethal consequences of multidrug resistance.