Resident Macrophages Cloak Tissue Microlesions to Prevent Neutrophil-Driven Inflammatory Damage.

Neutrophils are attracted to and generate dense swarms at sites of cell damage in diverse tissues, often extending the local disruption of organ architecture produced by the initial insult. Whether the inflammatory damage resulting from such neutrophil accumulation is an inescapable consequence of parenchymal cell death has not been explored. Using a combination of dynamic intravital imaging and confocal multiplex microscopy, we report here that tissue-resident macrophages rapidly sense the death of individual cells and extend membrane processes that sequester the damage, a process that prevents initiation of the feedforward chemoattractant signaling cascade that results in neutrophil swarms. Through this "cloaking" mechanism, the resident macrophages prevent neutrophil-mediated inflammatory damage, maintaining tissue homeostasis in the face of local cell injury that occurs on a regular basis in many organs because of mechanical and other stresses. VIDEO ABSTRACT.

TLR9 triggers MyD88-independent anti-inflammatory signaling in lupus.

Activation of Toll-like receptor 7 (TLR7) can induce lupus in mice, whereas activation of TLR9 can prevent it, even though both receptors interact with myeloid differentiation primary response gene 88 (MyD88) for downstream signaling. How TLR9 triggers anti-inflammatory responses in autoimmunity is unclear. Leibler et al. recently reported that TLR9 initiates anti-inflammatory signaling and inhibits lupus pathogenesis in a MyD88-independent but ligand-dependent manner.

Bioactive compounds from Huashi Baidu decoction possess both antiviral and anti-inflammatory effects against COVID-19.

The coronavirus disease 2019 (COVID-19) pandemic is an ongoing global health concern, and effective antiviral reagents are urgently needed. Traditional Chinese medicine theory-driven natural drug research and development (TCMT-NDRD) is a feasible method to address this issue as the traditional Chinese medicine formulae have been shown effective in the treatment of COVID-19. Huashi Baidu decoction (Q-14) is a clinically approved formula for COVID-19 therapy with antiviral and anti-inflammatory effects. Here, an integrative pharmacological strategy was applied to identify the antiviral and anti-inflammatory bioactive compounds from Q-14. Overall, a total of 343 chemical compounds were initially characterized, and 60 prototype compounds in Q-14 were subsequently traced in plasma using ultrahigh-performance liquid chromatography with quadrupole time-of-flight mass spectrometry. Among the 60 compounds, six compounds (magnolol, glycyrrhisoflavone, licoisoflavone A, emodin, echinatin, and quercetin) were identified showing a dose-dependent inhibition effect on the SARS-CoV-2 infection, including two inhibitors (echinatin and quercetin) of the main protease (Mpro), as well as two inhibitors (glycyrrhisoflavone and licoisoflavone A) of the RNA-dependent RNA polymerase (RdRp). Meanwhile, three anti-inflammatory components, including licochalcone B, echinatin, and glycyrrhisoflavone, were identified in a SARS-CoV-2-infected inflammatory cell model. In addition, glycyrrhisoflavone and licoisoflavone A also displayed strong inhibitory activities against cAMP-specific 3',5'-cyclic phosphodiesterase 4 (PDE4). Crystal structures of PDE4 in complex with glycyrrhisoflavone or licoisoflavone A were determined at resolutions of 1.54 Å and 1.65 Å, respectively, and both compounds bind in the active site of PDE4 with similar interactions. These findings will greatly stimulate the study of TCMT-NDRD against COVID-19.

Bioclay Enzyme with Bimetal Synergistic Sterilization and Infectious Wound Regeneration.

Bacteria invasion is the main factor hindering the wound-healing process. However, current antibacterial therapies inevitably face complex challenges, such as the abuse of antibiotics or severe inflammation during treatment. Here, a drug-free bioclay enzyme (Bio-Clayzyme) consisting of Fe2+-tannic acid (TA) network-coated kaolinite nanoclay and glucose oxidase (GOx) was reported to destroy harmful bacteria via bimetal antibacterial therapy. At the wound site, Bio-Clayzyme was found to enhance the generation of toxic hydroxyl radicals for sterilization via cascade catalysis of GOx and Fe2+-mediated peroxidase mimetic activity. Specifically, the acidic characteristics of the infection microenvironment accelerated the release of Al3+ from kaolinite, which further led to bacterial membrane damage and amplified the antibacterial toxicity of Fe2+. Besides, Bio-Clayzyme also performed hemostasis and anti-inflammatory functions inherited from Kaol and TA. By the combination of hemostasis and anti-inflammatory and bimetal synergistic sterilization, Bio-Clayzyme achieves efficient healing of infected wounds, providing a revolutionary approach for infectious wound regeneration.

ZNF281 enhances cardiac reprogramming by modulating cardiac and inflammatory gene expression.

Direct reprogramming of fibroblasts to cardiomyocytes represents a potential means of restoring cardiac function following myocardial injury. AKT1 in the presence of four cardiogenic transcription factors, GATA4, HAND2, MEF2C, and TBX5 (AGHMT), efficiently induces the cardiac gene program in mouse embryonic fibroblasts but not adult fibroblasts. To identify additional regulators of adult cardiac reprogramming, we performed an unbiased screen of transcription factors and cytokines for those that might enhance or suppress the cardiogenic activity of AGHMT in adult mouse fibroblasts. Among a collection of inducers and repressors of cardiac reprogramming, we discovered that the zinc finger transcription factor 281 (ZNF281) potently stimulates cardiac reprogramming by genome-wide association with GATA4 on cardiac enhancers. Concomitantly, ZNF281 suppresses expression of genes associated with inflammatory signaling, suggesting the antagonistic convergence of cardiac and inflammatory transcriptional programs. Consistent with an inhibitory influence of inflammatory pathways on cardiac reprogramming, blockade of these pathways with anti-inflammatory drugs or components of the nucleosome remodeling deacetylase (NuRD) complex, which associate with ZNF281, stimulates cardiac gene expression. We conclude that ZNF281 acts at a nexus of cardiac and inflammatory gene programs, which exert opposing influences on fibroblast to cardiac reprogramming.

Bilirubin ameliorates osteoarthritis via activating Nrf2/HO-1 pathway and suppressing NF-κB signalling.

Osteoarthritis (OA) is a chronic degenerative joint disease that affects worldwide. Oxidative stress plays a critical role in the chronic inflammation and OA progression. Scavenging overproduced reactive oxygen species (ROS) could be rational strategy for OA treatment. Bilirubin (BR) is a potent endogenous antioxidant that can scavenge various ROS and also exhibit anti-inflammatory effects. However, whether BR could exert protection on chondrocytes for OA treatment has not yet been elucidated. Here, chondrocytes were exposed to hydrogen peroxide with or without BR treatment. The cell viability was assessed, and the intracellular ROS, inflammation cytokines were monitored to indicate the state of chondrocytes. In addition, BR was also tested on LPS-treated Raw264.7 cells to test the anti-inflammation property. An in vitro bimimic OA microenvironment was constructed by LPS-treated Raw264.7 and chondrocytes, and BR also exert certain protection for chondrocytes by activating Nrf2/HO-1 pathway and suppressing NF-κB signalling. An ACLT-induced OA model was constructed to test the in vivo therapeutic efficacy of BR. Compared to the clinical used HA, BR significantly reduced cartilage degeneration and delayed OA progression. Overall, our data shows that BR has a protective effect on chondrocytes and can delay OA progression caused by oxidative stress.

Rhizoma Paridis saponins attenuate Gram-negative bacteria-induced inflammatory acne by binding to KEAP1 and modulating Nrf2 and MAPK pathways.

Acne vulgaris represents a chronic inflammatory condition, the pathogenesis of which is closely associated with the altered skin microbiome. Recent studies have implicated a profound role of Gram-negative bacteria in acne development, but there is a lack of antiacne agents targeting these bacteria. Polyphyllins are major components of Rhizoma Paridis with great anti-inflammatory potential. In this study, we aimed to evaluate the antiacne effects and the underlying mechanisms of PPH and a PPH-enriched Rhizoma Paridis extract (RPE) in treating the Gram-negative bacteria-induced acne. PPH and RPE treatments significantly suppressed the mRNA and protein expressions of interleukin (IL)-1ß and IL-6 in lipopolysaccharide (LPS)-induced RAW 264.7 and HaCaT cells, along with the intracellular reactive oxygen species (ROS) generation. Furthermore, PPH and RPE inhibited the nuclear translocation of nuclear factor kappa-B (NF-κB) P65 in LPS-induced RAW 264.7 cells. Based on molecular docking, PPH could bind to kelch-like ECH-associated protein 1 (KEAP1) protein. PPH and RPE treatments could activate nuclear factor erythroid 2-related factor 2 (NRF2) and upregulate haem oxygenase-1 (HO-1). Moreover, RPE suppressed the mitogen-activated protein kinase (MAPK) pathway. Therefore, PPH-enriched RPE showed anti-inflammatory and antioxidative effects in vitro, which is promising for alternative antiacne therapeutic.

Navigating the future of retinitis pigmentosa treatments: A comprehensive analysis of therapeutic approaches in rd10 mice.

Retinitis pigmentosa (RP) is a degenerative disease, caused by genetic mutations that lead to a loss in photoreceptors. For research on RP, rd10 mice, which carry mutations in the phosphodiesterase (PDE) gene, exhibit degenerative patterns comparable to those of patients with RP, making them an ideal model for investigating potential treatments. Although numerous studies have reported the potential of biochemical drugs, gene correction, and stem cell transplantation in decelerating rd10 retinal degeneration, a comprehensive review of these studies has yet to be conducted. Therefore, here, a comparative analysis of rd10 mouse treatment research over the past decade was performed. Our findings suggest that biochemical drugs capable of inhibiting the inflammatory response may be promising therapeutics. Additionally, significant progress has been made in the field of gene therapy; nevertheless, challenges such as strict delivery requirements, bystander editing, and off-target effects still need to be resolved. Nevertheless, secretory function is the only unequivocal protective effect of stem cell transplantation. In summary, this review presents a comprehensive analysis and synthesis of the treatment approaches employing rd10 mice as experimental subjects, describing a clear pathway for future RP treatment research and identifies potential clinical interventions.

Beyond the Coagulation Cascade: Vitamin K and Its Multifaceted Impact on Human and Domesticated Animal Health.

Vitamin K (VK) is an essential micronutrient impacting many systems in the body. This lipid-soluble vitamin is found in various plant and animal products and is absorbed via the lymphatic system. This biomolecule's importance to human health includes but is not limited to its promotion of brain, cardiovascular, bone, and immune functions. These biological properties are also necessary for maintaining domesticated animal health. The synergistic impact of both VK and vitamin D (VD) maximizes these health benefits, specifically for the circulatory and skeletal systems. This manuscript reviews VK's properties, molecular structures, nutrikinetics, mechanisms of action, daily requirements, safety in supplemental form, biomarkers used for its detection, and impacts on various organs. The purpose of synthesizing this information is to evaluate the potential uses of VK for the treatment or prevention of diseases.

Quantitative Analysis and Molecular Docking Simulation of Flavonols from Eruca sativa Mill. and Their Effect on Skin Barrier Function.

Eruca sativa is a commonly used edible plant in Italian cuisine. E. sativa 70% ethanol extract (ES) was fractionated with five organic solvents, including n-hexane (EHex), chloroform (ECHCl3), ethyl acetate (EEA), n-butyl alcohol (EBuOH), and water (EDW). Ethyl acetate fraction (EEA) had the highest antioxidant activity, which was correlated with the total polyphenol and flavonoid content. ES and EEA acted as PPAR-α ligands by PPAR-α competitive binding assay. EEA significantly increased cornified envelope formation as a keratinocyte terminal differentiation marker in HaCaT cells. Further, it significantly reduced nitric oxide and pro-inflammatory cytokines (IL-6 and TNF-α) in lipopolysaccharide-stimulated RAW 264.7 cells. The main flavonol forms detected in high amounts from EEA are mono-and di-glycoside of each aglycone. The main flavonol form of EEA is the mono-glycoside of each aglycone detected, and the most abundant flavonol mono-glycoside is kaempferol 3-glucoside 7.4%, followed by quercetin-3-glucoside 2.3% and isorhamnetin 3-glucoside 1.4%. Flavonol mono-glycosides were shown to be a potent PPAR-α ligand using molecular docking simulation and showed the inhibition of nitric oxide. These results suggest that the flavonol composition of E. sativa is suitable for use in improving skin barrier function and inflammation in skin disorders, such as atopic dermatitis.

Dual Immunoglobulin Domain-Containing Cell Adhesion Molecule Increases Early in Renal Tubular Cell Injury and Plays Anti-Inflammatory Role.

Dual immunoglobulin domain-containing cell adhesion molecule (DICAM) is a type I transmembrane protein that presents in various cells including renal tubular cells. This study evaluated the expression and protective role of DICAM in renal tubular cell injury. HK-2 cells were incubated and treated with lipopolysaccharide (LPS, 30 µg/mL) or hydrogen peroxide (H2O2, 100 µM) for 24 h. To investigate the effect of the gene silencing of DICAM, small interfering RNA of DICAM was used. Additionally, to explain its role in cellular response to injury, DICAM was overexpressed using an adenoviral vector. DICAM protein expression levels significantly increased following treatment with LPS or H2O2 in HK-2 cells. In response to oxidative stress, DICAM showed an earlier increase (2-4 h following treatment) than neutrophil gelatinase-associated lipocalin (NGAL) (24 h following treatment). DICAM gene silencing increased the protein expression of inflammation-related markers, including IL-1ß, TNF-α, NOX4, integrin ß1, and integrin ß3, in H2O2-induced HK-2 cell injury. Likewise, in the LPS-induced HK-2 cell injury, DICAM knockdown led to a decrease in occludin levels and an increase in integrin ß3, IL-1ß, and IL-6 levels. Furthermore, DICAM overexpression followed by LPS-induced HK-2 cell injury resulted in an increase in occludin levels and a decrease in integrin ß1, integrin ß3, TNF-α, IL-1ß, and IL-6 levels, suggesting an alleviating effect on inflammatory responses. DICAM was elevated in the early stage of regular tubular cell injury and may protect against renal tubular injury through its anti-inflammatory properties. DICAM has a potential as an early diagnostic marker and therapeutic target for renal cell injury.

Anti-Melanogenic and Anti-Inflammatory Effects of 2'-Hydroxy-4',6'-dimethoxychalcone in B16F10 and RAW264.7 Cells.

Chalcone is a type of flavonoid compound that is widely biosynthesized in plants. Studies have shown that consuming flavonoids from fruits and vegetables or applying individual ingredients reduces the risk of skin disease. However, the effects of chalcone on melanogenesis and inflammation have not been fully investigated. The aim of this study was to evaluate the anti-melanogenic and anti-inflammatory effects of 2'-hydroxy-3,4'-dimethoxychalcone (3,4'-DMC), 2'-hydroxy-4,4'-dimethoxychalcone (4,4'-DMC), 2'-hydroxy-3',4'-dimethoxychalcone (3',4'-DMC), and 2'-hydroxy-4',6'-dimethoxychalcone (4',6'-DMC). Among the derivatives of 2'-hydroxy-4'-methoxychalcone, 4',6'-DMC demonstrated the most potent melanogenesis-inhibitory and anti-inflammatory effects. As evidenced by various biological assays, 4',6'-DMC showed no cytotoxicity and notably decreased the expression of tyrosinase, tyrosinase-related protein (TRP)-1, and TRP-2 enzymes. Furthermore, it reduced cellular melanin content and intracellular tyrosinase activity in B16F10 melanoma cells by downregulating microphthalmia-associated transcription factor (MITF), cAMP-dependent protein kinase (PKA), cAMP response element-binding protein (CREB), p38, c-Jun N-terminal kinase (JNK), ß-catenin, glycogen synthase kinase-3ß (GSK3ß), and protein kinase B (AKT) proteins, while upregulating extracellular signal-regulated kinase (ERK) and p-ß-catenin. Additionally, treatment with 4',6'-DMC significantly mitigated the lipopolysaccharide (LPS)-induced expression of NO, PGE2, inflammatory cytokines, COX-2, and iNOS proteins. Overall, 4',6'-DMC treatment notably alleviated LPS-induced damage by reducing nuclear factor kappa B (NF-κB), p38, JNK protein levels, and NF-kB/p65 nuclear translocation. Finally, the topical applicability of 4',6'-DMC was evaluated in a preliminary human skin irritation test and no adverse effects were found. These findings suggest that 4',6'-DMC may offer new possibilities for use as functional ingredients in cosmeceuticals and ointments.

Pogostemon cablin Extract Promotes Wound Healing through OR2AT4 Activation and Exhibits Anti-Inflammatory Activity.

Skin healing occurs through an intricate process called wound healing which comprises four phases: coagulation and hemostasis, inflammation, cellular proliferation, and remodeling. Chronic wounds often arise because of prolonged or excessive inflammation, which hinders the healing process and wound closure. Despite the recognized efficacy of Pogostemon cablin (patchouli) in wound healing, the precise mechanism of action of Pogostemon cablin extract (PCE) on inflammation and wound healing remains poorly understood. In this study, we investigated the effects of PCE on cell proliferation and wound healing, as well as its anti-inflammatory activity, using in vitro experiments. We found that PCE increased cell proliferation and expression of the cell proliferation marker Ki67 and accelerated wound healing in human keratinocytes through the activation of OR2AT4. Furthermore, PCE exhibited anti-inflammatory effects by decreasing the levels of pro-inflammatory cytokines interleukin-6 and -8 in lipopolysaccharide-treated and TNF-α-exposed THP-1 and HaCaT cells, respectively. Overall, these findings suggest that PCE holds therapeutic potential by promoting cell proliferation, facilitating wound healing, and exerting anti-inflammatory effects.

Synthesis of urolithin derivatives and their anti-inflammatory activity.

Two series of urolithin derivatives, totally 38 compounds, were synthesized. Their anti-inflammatory activity was investigated by detecting the inhibitory effects on the expression of TNF-α in bone marrow-derived macrophages (BMDMs), showing that 24 of 38 ones reduced the expression of TNF-α. Compound B2, the ring C opened derivative of urolithin B with a butoxycarbonyl substitution in ring A, showed the strongest inhibitory activity compared with that of indomethacin. Furthermore, B2 treatment decreased the expression of pro-inflammatory factors IL-1ß, IL-6, iNOS and COX-2. Mechanically, the anti-inflammatory effect of B2 was related to the inhibition of NF-κB signaling pathway. These results clearly illustrated that B2 hold potential for application as an anti-inflammatory agent. The present study provided a viable approach to modify the gut metabolites for anti-inflammatory drug development.

Peptide-Based Nanoparticles Suppress Hepatic Inflammation via Blockage of Human Antigen R.

Human antigen R (HuR), which is a mRNA-binding protein that stabilizes and regulates mRNA translation, is found to have increased expression in inflammation, cancer and other diseases, making HuR to be a promising drug target. This study reports a peptide-based nanoparticle (NP) system exhibits potent anti-inflammatory activity to ameliorate acute liver injury via the ability of peptides to inhibit the mRNA binding site of HuR and block downstream signaling. Molecular modeling provided structural evidence indicating that the peptides interact with the RNA-binding site of HuR, mainly via hydrogen-bonding and hydrophobic interactions. These peptide-based NPs can act as nanocarriers to deliver peptides into cells to compete with the mRNA binding site of HuR, evidenced by the reduction of antibody recognition to the native protein and the exhibition of anti-inflammatory activity against activated macrophage cells, with no adverse effect in vitro and in vivo. In LPS/D-GalN-induced hepatic sepsis with high dosage of LPS/GalN, administration of the NPs significantly attenuated necrosis and HuR expression, resulting in the significant improvement of animal survival rate, suggesting their therapeutic potential for hepatic inflammation and a broad range of HuR-overexpressed diseases.

Carbon Dots with Integrated Photothermal Antibacterial and Heat-Enhanced Antioxidant Properties for Diabetic Wound Healing.

Diabetic wounds pose a persistent challenge due to their slow healing nature, primarily caused by bacterial infection and excessive reactive oxygen species (ROS)-induced inflammation. In this study, carbon dots with synergistic antibacterial and antioxidant properties, referred to as AA-CDs, are developed specifically for diabetic wound healing using a straightforward solvothermal method. By utilizing cost-effective precursors like citric acid and ascorbic acid, AA-CDs are engineered to possess tailored functions of photothermal sterilization and ROS scavenging. The resulting AA-CDs demonstrats broad-spectrum antibacterial activity, particularly against multidrug-resistant strains, along with efficient ROS scavenging both in solution and within cells. Additionally, AA-CDs exhibits a protective effect against oxidative stress-induced damage. Notably, with a high photothermal conversion efficiency (41.18%), AA-CDs displays heat-enhanced antioxidant performance, providing not only augmented ROS scavenging but also additional protection against oxidative stress, yielding a true "1 + 1 > 2" effect. To facilitate their use in vivo, AA-CDs are incorporated into a thermally responsive hydrogel, which exhibits evident anti-inflammatory properties by modulating inflammatory factors and significantly promots the healing of diabetic wounds. This study underscores the value of integrated platforms for diabetic wound healing and highlights the potential of versatile CDs as promising therapeutic agents in biomedical applications.

NIR Absorbing Organic Chromophores Combination with NSAIDs for Remodeling of the Inflammatory Microenvironment to Amplify Tumor Ferroptosis-Photothermal Synergistic Therapy.

Photothermal therapy has emerged as a promising approach for cancer treatment, which can cause ferroptosis to enhance immunotherapeutic efficacy. However, excessively generated immunogenicity will induce serious inflammatory response syndrome, resulting in a discounted therapeutic effect. Herein, a kind of NIR absorption small organic chromophore nanoparticles (TTHM NPs) with high photothermal conversion efficiency (68.33%) is developed, which can induce mitochondria dysfunction, generate mitochondrial superoxide, and following ferroptosis. TTHM NPs-based photothermal therapy is combined with Sulfasalazine (SUZ), a kind of nonsteroidal anti-inflammatory drugs, to weaken inflammation and promote ferroptosis through suppressing glutamate/cystine (Glu/Cys) antiporter system Xc- (xCT). Additionally, the combination of SUZ with PTT can induce immunogenic cell death (ICD), followed by promoting the maturation of DCs and the attraction of CD8+ T cell, which will secrete IFN-γ and trigger self-amplified ferroptosis via inhibiting xCT and simulating Acyl-CoA synthetase long-chain family member 4 (ACSL4). Moreover, the in vivo results demonstrate that this combination therapy can suppress the expression of inflammatory factors, enhance dendritic cell activation, facilitate T-cell infiltration, and realize effective thermal elimination of primary tumors and distant tumors. In general, this work provides an excellent example of combined medication and stimulates new thinking about onco-therapy and inflammatory response.

Human Adipose Tissue Lysate-Based Hydrogel for Lasting Immunomodulation to Effectively Improve Spinal Cord Injury Repair.

The long-term inflammatory microenvironment is one of the main obstacles to inhibit acute spinal cord injury (SCI) repair. The natural adipose tissue-derived extracellular matrix hydrogel shows effective anti-inflammatory regulation because of its unique protein components. However, the rapid degradation rate and removal of functional proteins during the decellularization process impair the lasting anti-inflammation function of the adipose tissue-derived hydrogel. To address this problem, adipose tissue lysate provides an effective way for SCI repair due to its abundance of anti-inflammatory and nerve regeneration-related proteins. Thereby, human adipose tissue lysate-based hydrogel (HATLH) with an appropriate degradation rate is developed, which aims to in situ long-term recruit and induce anti-inflammatory M2 macrophages through sustainedly released proteins. HATLH can recruit and polarize M2 macrophages while inhibiting pro-inflammatory M1 macrophages regardless of human or mouse-originated. The axonal growth of neuronal cells also can be effectively improved by HATLH and HATLH-induced M2 macrophages. In vivo experiments reveal that HATLH promotes endogenous M2 macrophages infiltration in large numbers (3.5 × 105/100 µL hydrogel) and maintains a long duration for over a month. In a mouse SCI model, HATLH significantly inhibits local inflammatory response, improves neuron and oligodendrocyte differentiation, enhances axonal growth and remyelination, as well as accelerates neurological function restoration.

Tumor Homing Chimeric Peptide Rhomboids to Improve Photodynamic Performance by Inhibiting Therapy-Upregulated Cyclooxygenase-2.

Negative therapeutic feedback of inflammation would extensively attenuate the antitumor effect of photodynamic therapy (PDT). In this work, tumor homing chimeric peptide rhomboids (designated as NP-Mel) are fabricated to improve photodynamic performance by inhibiting PDT-upregulated cyclooxygenase-2 (COX-2). The hydrophobic photosensitizer of protoporphyrin IX (PpIX) and palmitic acid are conjugated onto the neuropilin receptors (NRPs) targeting peptide motif (CGNKRTR) to obtain tumor homing chimeric peptide (Palmitic-K(PpIX)CGNKRTR), which can encapsulate the COX-2 inhibitor of meloxicam. The well dispersed NP-Mel not only improves the drug stability and reactive oxygen species (ROS) production ability, but also increase the breast cancer targeted drug delivery to intensify the PDT effect. In vitro and in vivo studies verify that NP-Mel will decrease the secretion of prostaglandin E2 (PGE2) after PDT treatment, inducing the downregulation of IL-6 and TNF-α expressions to suppress PDT induced inflammation. Ultimately, an improved PDT performance of NP-Mel is achieved without inducing obvious systemic toxicity, which might inspire the development of sophisticated nanomedicine in consideration of the feedback induced therapeutic resistance.

Glycosylation of 6-gingerol and unusual spontaneous deglucosylation of two novel intermediates to form 6-shogaol-4'-O-ß-glucoside by bacterial glycosyltransferase.

6-Gingerol is a major phenolic compound within ginger (Zingiber officinale), often used in healthcare; however, its lower bioavailability is partly due to its poor solubility. Four bacterial glycosyltransferases (GTs) were tested to glycosylate 6-gingerol into soluble gingerol glucosides. BsUGT489 was a suitable GT to biotransform 6-gingerol into five significant products, which could be identified via nucleic magnetic resonance and mass spectrometry as 6-gingerol-4',5-O-ß-diglucoside (1), 6-gingerol-4'-O-ß-glucoside (2), 6-gingerol-5-O-ß-glucoside (3), 6-shogaol-4'-O-ß-glucoside (4), and 6-shogaol (5). The enzyme kinetics of BsUGT489 showed substrate inhibition toward 6-gingerol for producing two glucosides. The kinetic parameters were determined as KM (110 µM), kcat (862 min-1), and KI (571 µM) for the production of 6-gingerol-4'-O-ß-glucoside (2) and KM (104 µM), kcat (889 min-1), and KI (545 µM) for the production of 6-gingerol-5-O-ß-glucoside (3). The aqueous solubility of the three 6-gingerol glucosides, compound (1) to (3), was greatly improved. However, 6-shogaol-4'-O-ß-glucoside (4) was found to be a product biotransformed from 6-shogaol (5). This study first confirmed that the glucose moiety at the C-5 position of both 6-gingerol-4',5-O-ß-diglucoside (1) and 6-gingerol-5-O-ß-glucoside (3) caused spontaneous deglucosylation through ß-elimination to form 6-shogaol-4'-O-ß-glucoside (4) and 6-shogaol (5), respectively. Moreover, the GTs could glycosylate 6-shogaol to form 6-shogaol-4'-O-ß-glucoside (4). The assays showed 6-shogaol-4'-O-ß-glucoside (4) had higher anti-inflammatory activity (IC50 value of 10.3 ± 0.2 µM) than 6-gingerol. The 6-gingerol-5-O-ß-glucoside (3) possessed 346-fold higher solubility than 6-shogaol, in which the highly soluble glucoside is a potential prodrug of 6-shogaol via spontaneous deglucosylation. This unusual deglucosylation plays a vital role in influencing the anti-inflammatory activity. IMPORTANCE: Both 6-gingerols and 6-shogaol possess multiple bioactivities. However, their poor solubility limits their application. The present study used bacterial GTs to catalyze the glycosylation of 6-gingerol, and the resulting gingerol glycosides were found to be new compounds with improved solubility and anti-inflammatory activity. In addition, two of the 6-gingerol glucosides were found to undergo spontaneous deglucosylation to form 6-shogaol or 6-shogaol glucosides. The unique spontaneous deglucosylation property of the new 6-gingerol glucosides makes them a good candidate for the prodrug of 6-shogaol.