Halo-Substituted Chalcones and Azachalcones-Inhibited, Lipopolysaccharited-Stimulated, Pro-Inflammatory Responses through the TLR4-Mediated Pathway

Synthesis of Flavonols and Assessment of Their Biological Activity as Anticancer Agents

A series of flavanols were synthesized to assess their biological activity against human non-small cell lung cancer cells (A549). Among the sixteen synthesized compounds, it was observed that compounds 6k (3.14 ± 0.29 µM) and 6l (0.46 ± 0.02 µM) exhibited higher potency compared to 5-fluorouracil (5-Fu, 4.98 ± 0.41 µM), a clinical anticancer drug which was used as a positive control. Moreover, compound 6l (4'-bromoflavonol) markedly induced apoptosis of A549 cells through the mitochondrial- and caspase-3-dependent pathways. Consequently, compound 6l might be developed as a candidate for treating or preventing lung cancer.

Ginsenoside F2-Mediated Intestinal Microbiota and Its Metabolite Propionic Acid Positively Impact the Gut-Skin Axis in Atopic Dermatitis Mice

Atopic dermatitis (AD) is a complex inflammatory skin disease induced by multiple factors. AD can also cause intestinal inflammation and disorders of the gut microbiota. Ginseng is a kind of edible and medicinal plant; its main active components are ginsenosides. Ginsenosides have a variety of anti-inflammatory effects and regulate the gut microbiota; however, their role in AD and the underlying mechanisms are unclear. In this study, we found that intragastric administration of ginsenoside F2 improved AD-like skin symptoms and reduced inflammatory cell infiltration, serum immunoglobulin E levels, and mRNA expression of inflammatory cytokines in AD mice. 16s rRNA sequencing analysis showed that ginsenoside F2 altered the intestinal microbiota structure and enriched the short-chain fatty acid-producing microbiota in AD mice. Metabolomic analysis revealed that ginsenoside F2 significantly increased the propionic acid (Pa) content of feces and serum in AD mice, which was positively correlated with significant enrichment of Parabacteroides goldsteinii and Lactobacillus plantarum in the intestines. Pa inhibits inflammatory responses in the gut and skin of AD mice through the G-protein-coupled receptor43/NF-κB pathway, thereby improving skin AD symptoms. These results revealed, for the first time, the mechanism by which ginsenoside F2 improves AD through the Pa (a metabolite of intestinal microbiota)-gut-skin axis.

Transcriptomic Integration Analyses Uncover Common Bisphenol A Effects Across Species and Tissues Primarily Mediated by Disruption of JUN/FOS, EGFR, ER, PPARG, and P53 Pathways

Bisphenol A (BPA) is a common endocrine disruptor widely used in the production of electronic, sports, and medical equipment, as well as consumer products like milk bottles, dental sealants, and thermal paper. Despite its widespread use, current assessments of BPA exposure risks remain limited due to the lack of comprehensive cross-species comparative analyses. To address this gap, we conducted a study aimed at identifying genes and fundamental molecular processes consistently affected by BPA in various species and tissues, employing an effective data integration method and bioinformatic analyses. Our findings revealed that exposure to BPA led to significant changes in processes like lipid metabolism, proliferation, and apoptosis in the tissues/cells of mammals, fish, and nematodes. These processes were found to be commonly affected in adipose, liver, mammary, uterus, testes, and ovary tissues. Additionally, through an in-depth analysis of signaling pathways influenced by BPA in different species and tissues, we observed that the JUN/FOS, EGFR, ER, PPARG, and P53 pathways, along with their downstream key transcription factors and kinases, were all impacted by BPA. Our study provides compelling evidence that BPA indeed induces similar toxic effects across different species and tissues. Furthermore, our investigation sheds light on the underlying molecular mechanisms responsible for these toxic effects. By uncovering these mechanisms, we gain valuable insights into the potential health implications associated with BPA exposure, highlighting the importance of comprehensive assessments and awareness of this widespread endocrine disruptor.

Dietary nano-selenium alleviated intestinal damage of juvenile grass carp (Ctenopharyngodon idella) induced by high-fat diet: Insight from intestinal morphology, tight junction, inflammation, anti-oxidization and intestinal microbiota

In recent years, high-fat diet (HFD) has been widely applied in aquaculture, which reduces the intestinal health of cultured fish. The current study evaluated the protective effects of nano-selenium (nano-Se) on intestinal health of juvenile grass carp (Ctenopharyngodon idella) fed with HFD. A total of 135 experimental fish were fed with a regular diet (Con), a HFD (HFD) and a HFD containing nano-Se at 0.6 mg/kg (HSe) for 10 weeks. The results showed that dietary nano-Se significantly improved the survival rate and feed efficiency which were reduced by HFD in juvenile grass carp (P < 0.05). Also, nano-Se (0.6 mg/kg) supplement alleviated intestinal damage caused by the HFD, thus maintaining the integrity of the intestine. Moreover, it significantly up-regulated the expression of genes related to tight junction (ZO-1, c laudin-3 and o ccludin), anti-oxidization (GPx4a andGPx4b), and the protein of ZO-1 in the intestine of juvenile grass carp, which were depressed by the HFD (P < 0.05). Furthermore, nano-Se supplementation significantly suppressed the expressions of genes related to the inflammation, including inflammatory cytokines (IL-8, IL-1β, IFN-γ, TNF-α and IL-6), signaling molecules (TLR4, p38 MAPK and NF-κB p65), and protein expression of NF-κB p65 and TNF-α in the intestine of juvenile grass carp which were induced by the HFD (P < 0.05). Besides, dietary nano-Se normalized the intestinal microbiota imbalance of juvenile grass carp caused by the HFD through increasing the abundance of the beneficial bacteria, e.g., Fusobacteria. Finally, dietary nano-Se increased the production of short chain fatty acids (SCFA) in the intestine, especially for butyric acid and caproic acid, which were negatively related to the increase of intestinal permeability and inflammation. In summary, supply of nano-Se (0.6 mg/kg) in HFD could effectively alleviate intestinal injury of juvenile grass carp by improving intestinal barrier function and reducing intestinal inflammation and oxidative stress. These positive effects may be due to the regulation of nano-Se on intestinal microbiota and the subsequently increased beneficial SCFA levels.

Structural effects of halogen bonding in iodochalcones

The structures of three iodochalcones, functionalized with fluorine or a nitro group, have been investigated to explore the impact of different molecular electrostatic distributions on the halogen bonding within each crystal structure. The strongly withdrawing nitro group presented a switch of the halogen bond from a lateral to a linear motif. Surprisingly, this appears to be influenced by a net positive shift in charge distribution around the lateral edges of the σ-hole, making the lateral I...I bonding motif less preferable. A channel of amphoteric I...I type II halogen bonds is observed for a chalcone molecule, which was not previously reported in chalcones, alongside an example of the common synthon involving extended linear chains of I...O₂N donor-acceptor halogen bonds. This work shows that halogenated chalcones may be an interesting target for developing halogen bonding as a significant tool within crystal engineering, a thus far underexplored area for this common structural motif.

Interdependence of Anti-Inflammatory and Antioxidant Properties of Squalene-Implication for Cardiovascular Health

Cardiovascular diseases (CVD) have been recognized as the leading cause of mortality worldwide, accounting for 31% of global mortality. Among the risk factors of CVD, hyperlipidemia has been established as the most potent risk factor. Statins, a class of drug that reduces lower-density lipoprotein cholesterol (LDL-C), are the preferred medical treatment. However, due to the development of statin-associated muscle symptoms, statins are associated with patients' discontinuation and nonadherence. Other statin-induced side effects, such as hepatotoxicity and gastrointestinal upset, all contribute to patients choosing alternative medicines. Squalene (SQ), an unsaturated hydrocarbon naturally synthesized in plants and animals, could become the alternative treatment or supplementary agent for cardiovascular health. SQ has been shown to exert cardioprotective effect via its antioxidant activity. Oxidative stress and inflammatory responses are closely related to each other, which proposes an interdependence relation between antioxidant and anti-inflammatory. Therefore, this review explores the interdependence between the antioxidant and anti-inflammatory effects of SQ implicated on cardiovascular health.

Modulation of the Innate Immune Response by Targeting Toll-like Receptors: A Perspective on Their Agonists and Antagonists

Toll-like receptors (TLRs) are a class of proteins that recognize pathogen-associated molecular patterns (PAMPs) and damaged-associated molecular patterns (DAMPs), and they are involved in the regulation of innate immune system. These transmembrane receptors, localized at the cellular or endosomal membrane, trigger inflammatory processes through either myeloid differentiation primary response 88 (MyD88) or TIR-domain-containing adapter-inducing interferon-β (TRIF) signaling pathways. In the last decades, extensive research has been performed on TLR modulators and their therapeutic implication under several pathological conditions, spanning from infections to cancer, from metabolic disorders to neurodegeneration and autoimmune diseases. This Perspective will highlight the recent discoveries in this field, emphasizing the role of TLRs in different diseases and the therapeutic effect of their natural and synthetic modulators, and it will discuss insights for the future exploitation of TLR modulators in human health.

Tetramethylpyrazine attenuates endotoxin-induced retinal inflammation by inhibiting microglial activation via the TLR4/NF-κB signalling pathway

Ocular inflammation is a common pathological condition of a series of retinal degenerative diseases. Tetramethylpyrazine (TMP), a Chinese herbal extraction, is widely used in the treatment of several ocular diseases in Eastern countries. However, the exact mechanisms correlating the vision protective effects of TMP have not been elucidated. Thus, this study aimed to investigate TMP's molecular targets in anti-inflammatory activity in endotoxin lipopolysaccharide (LPS)-induced retinal inflammation both in vitro and in vivo. The primary cultured retinal microglial cells were pretreated with TMP and then activated by LPS. We found pretreatment with TMP significantly inhibited LPS-induced upregulation of CD68, a marker of mononuclear microglia activation. The morphological changes induced by LPS were also inhibited by the TMP pretreatment. Moreover, Toll like receptor 4 (TLR4), phosphorylation of inhibitor of NF-κB alpha (p-IκB-α) and the translocation of nuclear factor kappa B p65 (NF-κB p65) were significantly downregulated in retinal microglial cells with TMP pretreatment, which indicated that TMP might suppress LPS-induced retinal microglial activation through TLR4/NF-κB signalling pathway. And these results were confirmed in vivo. Pretreatment with TMP inhibited microglial activation, migration and regeneration, especially in ganglion cell layer (GCL). In addition to the inhibition of TLR4, TMP significantly inhibited the translocation of NF-κB p-65 to the nucleus in vivo. The downstream genes of NF-κB, such as the pro-inflammatory cytokines interleukin-6 (IL-6), tumor necrosis factor alpha (TNF-α) and interleukin-1β (IL-1β), were significantly downregulated by TMP pretreatment in the retina. Accordingly, the increased expression of cleaved caspase-3 and the decreased ratio of B-cell lymphoma-2 (Bcl-2) to Bcl-2 associated X Protein (Bax) were significantly attenuated by TMP. TUNEL assay also demonstrated that TMP exerted neuroprotective effects in the retina. Therefore, this study elucidated a novel mechanism that TMP inhibits retinal inflammation by inhibiting microglial activation via a TLR4/NF-κB signalling pathway.

Promising anti-inflammatory effects of chalcones via inhibition of cyclooxygenase, prostaglandin E2, inducible NO synthase and nuclear factor κb activities

Chalcones (1, 3-Diphenyl-2-propen-1-one) consist of a three carbon α, β-unsaturated carbonyl system and act as precursors for the biosynthesis of flavonoids in plants. However, laboratory synthesis of various chalcones has also been reported. Both natural and synthetic chalcones are known to exhibit a variety of pharmacological activities such as anti-inflammatory, antitumor, antibacterial, antifungal, antimalarial and antituberculosis. These promising activities, ease of synthesis and simple chemical structure have awarded chalcones considerable attraction. This review focuses on the anti-inflammatory effects of chalcones, caused by their inhibitory action primarily against the activities and expressions of four key inflammatory mediators viz., cyclooxygenase, prostaglandin E₂, inducible NO synthase, and nuclear factor κB. Various methodologies for the synthesis of chalcones have been discussed. The potency of recently synthesized chalcones is given in terms of their IC₅₀ values. Structure-Activity Relationships (SARs) of a variety of chalcone derivatives have been discussed. Computational methods were applied to calculate the ideal orientation of a typical chalcone scaffold against three enzymes, namely, cyclooxygenase-1, cyclooxygenase-2 and inducible NO synthase for the formation of stable complexes. The global market of anti-inflammatory drugs and its expected growth (from 2018 to 2026) have been discussed. SAR analysis, docking studies, and future prospects all together provide useful clues for the synthesis of novel chalcones of improved anti-inflammatory activities.