Serial Passaging of RAW 264.7 Cells Modulates Intracellular AGE Formation and Downregulates RANKL-Induced In Vitro Osteoclastogenesis

Reversing Oxinflammation Associated with Glycative Stress and Formation of Advanced Glycation End Products with a Dietary Supplement Containing Rosemary Extract

Objective

Skin aging is accelerated by glycative stress, which promotes the accumulation of advanced glycation end products (AGEs) and impairs the extracellular matrix. A randomized, double-blinded, placebo-controlled trial evaluated a dietary supplement containing rosemary extract (BioR), demonstrating tissular and visible improvements in skin quality. The data reported herein evaluated markers associated with glycative stress and AGEs from skin biopsies and tape strips obtained following dietary supplement use.

Methods

Female participants (N=104), aged 40 to 65 years, with moderate-to-severe skin dullness and roughness/texture, and mild-to-moderate erythema, pore size, and uneven pigmentation were randomized to BioR (n=52) or placebo ([PLB] n=52). Capsules were taken with food over 12 weeks. Subjects (n=16, BioR; n=16, PLB) underwent 3mm punch biopsies (volar upper arm) and tape stripping (16 tape strips, each; volar forearm) at baseline and 12 weeks for analysis of 4-hydroxynonenal protein adducts (4HNE [oxidative stress marker]) and AGEs.

Results

Immunohistochemistry and ELISA revealed that levels of 4HNE protein adducts were significantly decreased from baseline in the BioR versus PLB group (p<0.005; biopsies) and significantly decreased from baseline in the BioR group alone (p<0.05; tape strips) at 12 weeks. Significant reductions in AGEs occurred in the BioR versus PLB group (p<0.005; biopsies) at 12 weeks. No significant changes from baseline occurred in 4HNE protein adduct levels or AGEs in the PLB group.

Conclusion

After 12 weeks, a dietary supplement containing rosemary extract led to significant reductions in a marker associated with oxidative stress, a component of glycation, and AGEs versus placebo in skin in addition to visible improvements in skin quality.

UPLC-QToF-MS/MS screening and characterization of Symphorema polyandrum Wight and in vitro assessment of its antioxidant, anticancer, and anti-inflammatory potential

Symphorema polyandrum belongs to the Lamiaceae family and is locally known as Badichang or mahasindhu. In this study, we performed Soxhlet extraction to prepare methanolic and hydromethanolic extracts, followed by quantification of their total phenolic content and total flavonoid content. Qualitative analysis of both the extracts was conducted to determine the presence of different phytochemicals. In addition, we aimed to identify the important phytochemical constituents in the methanolic extracts of S. polyandrum (SPM) using ultra-performance liquid chromatography hyphenated with high-resolution mass spectrometry (UPLC-ESI-QTOF-MSE). Furthermore, this study investigated the antioxidant, anticancer and anti-inflammatory properties of SPM and its safety profile in the normal fibroblast cell line L929. A colony proliferation assay and a Griess assay were performed to evaluate the effects of SPM on colony formation and nitric oxide (NO) production. A total of 13 important phytochemicals were identified and reported. The methanolic extract of SPM demonstrated significant antioxidant activity. SPM also showed substantial antiproliferative activity on MDA-MB-231 triple-negative breast cancer cells, with an IC50 value of 45.53 ± 1.63 µg/ml, and also reduced the survival of these cancer cells by promoting nuclear fragmentation and condensation without causing harm to normal cells. SPM inhibits the colony formation and reduces the nitric oxide (NO) production. The anti-inflammatory potential of SPM was assessed utilizing the murine alveolar macrophages (J774.A.1) as an in vitro model, and SPM effectively lowered the levels of proinflammatory cytokines such as TNF-α and IL-6. These findings emphasized the antiproliferative potential of SPM to cancer cells, along with its anti-inflammatory, and antioxidant capabilities, indicating the therapeutic efficacy of this medicinal plant.

Activation of Immune Responses Through the RIG-I Pathway Using TRITC-Dextran Encapsulated Nanoparticles

Pathogen-associated molecular patterns (PAMPs) are highly conserved motifs originating from microorganisms that act as ligands for pattern recognition receptors (PRRs), which are crucial for defense against pathogens. Thus, PAMP-mimicking vaccines may induce potent immune activation and provide broad-spectrum protection against microbes. Dextran encapsulation can regulate the surface characteristics of nanoparticles (NPs) and induces their surface modification. To determine whether dextran-encapsulated NPs can be used to develop antiviral vaccines by mimicking viral PAMPs, we synthesized NPs in a cyclohexane inverse miniemulsion (Basic-NPs) and further encapsulated them with dextran or tetramethylrhodamine isothiocyanate (TRITC)-dextran (Dex-NPs or TDex-NPs). We hypothesized that these dextran encapsulated NPs could activate innate immunity through cell surface or cytosolic PRRs. In vitro and in vivo experiments were performed using RAW 264.7 and C57BL/6 mice to test different concentrations and routes of administration. Only TDex-NPs rapidly increased retinoic acid-inducible gene I (RIG-I) at 8 h and directly bound to it, producing 120-300 pg/ml of IFN-α via the ERK/NF-κB signaling pathway in both in vitro and in vivo models. The effect of TDex-NPs in mice was observed exclusively with footpad injections. Our findings suggest that TRITC-dextran encapsulated NPs exhibit surface properties for RIG-I binding, offering potential development as a novel antiviral and anticancer RIG-I agonist.

Macrophage variants in laboratory research: most are well done, but some are RAW

Macrophages play a pivotal role in the innate immune response. While their most characteristic function is phagocytosis, it is important not to solely characterize macrophages by this activity. Their crucial roles in body development, homeostasis, repair, and immune responses against pathogens necessitate a broader understanding. Macrophages exhibit remarkable plasticity, allowing them to modify their functional characteristics in response to the tissue microenvironment (tissue type, presence of pathogens or inflammation, and specific signals from neighboring cells) swiftly. While there is no single defined "macrophage" entity, there is a diverse array of macrophage types because macrophage ontogeny involves the differentiation of progenitor cells into tissue-resident macrophages, as well as the recruitment and differentiation of circulating monocytes in response to tissue-specific cues. In addition, macrophages continuously sense and respond to environmental cues and tissue conditions, adjusting their functional and metabolic states accordingly. Consequently, it is of paramount importance to comprehend the heterogeneous origins and functions of macrophages employed in in vitro studies, as each available in vitro macrophage model is associated with specific sets of strengths and limitations. This review centers its attention on a comprehensive comparison between immortalized mouse macrophage cell lines and primary mouse macrophages. It provides a detailed analysis of the strengths and weaknesses inherent in these in vitro models. Finally, it explores the subtle distinctions between diverse macrophage cell lines, offering insights into numerous factors beyond the model type that can profoundly influence macrophage function.

Onion (Allium cepa L.) Flavonoid Extract Ameliorates Osteoporosis in Rats Facilitating Osteoblast Proliferation and Differentiation in MG-63 Cells and Inhibiting RANKL-Induced Osteoclastogenesis in RAW 264.7 Cells

Osteoporosis, a prevalent chronic health issue among the elderly, is a global bone metabolic disease. Flavonoids, natural active compounds widely present in vegetables, fruits, beans, and cereals, have been reported for their anti-osteoporotic properties. Onion is a commonly consumed vegetable rich in flavonoids with diverse pharmacological activities. In this study, the trabecular structure was enhanced and bone mineral density (BMD) exhibited a twofold increase following oral administration of onion flavonoid extract (OFE). The levels of estradiol (E2), calcium (Ca), and phosphorus (P) in serum were significantly increased in ovariectomized (OVX) rats, with effects equal to alendronate sodium (ALN). Alkaline phosphatase (ALP) and tartrate-resistant acid phosphatase (TRAP) levels in rat serum were reduced by 35.7% and 36.9%, respectively, compared to the OVX group. In addition, the effects of OFE on bone health were assessed using human osteoblast-like cells MG-63 and osteoclast precursor RAW 264.7 cells in vitro as well. Proliferation and mineralization of MG-63 cells were promoted by OFE treatment, along with increased ALP activity and mRNA expression of osteoprotegerin (OPG)/receptor activator of nuclear factor-kappaB ligand (RANKL). Additionally, RANKL-induced osteoclastogenesis and osteoclast activity were inhibited by OFE treatment through decreased TRAP activity and down-regulation of mRNA expression-related enzymes in RAW 264.7 cells. Overall findings suggest that OFE holds promise as a natural functional component for alleviating osteoporosis.

Brucella Manipulates Host Cell Ferroptosis to Facilitate Its Intracellular Replication and Egress in RAW264.7 Macrophages

Brucella virulence relies on its successful intracellular life cycle. Modulating host cell death is a strategy for Brucella to survive and replicate intracellularly. Ferroptosis is a novel regulated cell death characterized by iron-triggered excessive lipid peroxidation, which has been proven to be associated with pathogenic bacteria infection. Thus, we attempted to explore if smooth-type Brucella infection triggers host cell ferroptosis and what role it plays in Brucella infection. We assessed the effects of Brucella infection on the lactate dehydrogenase release and lipid peroxidation levels of RAW264.7 macrophages; subsequently, we determined the effect of Brucella infection on the expressions of ferroptosis defense pathways. Furthermore, we determined the role of host cell ferroptosis in the intracellular replication and egress of Brucella. The results demonstrated that Brucella M5 could induce ferroptosis of macrophages by inhibiting the GPX4-GSH axis at the late stage of infection but mitigated ferroptosis by up-regulating the GCH1-BH4 axis at the early infection stage. Moreover, elevating host cell ferroptosis decreased Brucella intracellular survival and suppressing host cell ferroptosis increased Brucella intracellular replication and egress. Collectively, Brucella may manipulate host cell ferroptosis to facilitate its intracellular replication and egress, extending our knowledge about the underlying mechanism of how Brucella completes its intracellular life cycle.

Local application of zoledronate inhibits early bone resorption and promotes bone formation

Nonunion resulting from early bone resorption is common after bone transplantation surgery. In these patients, instability or osteoporosis causes hyperactive catabolism relative to anabolism, leading to graft resorption instead of fusion. Systemic zoledronate administration inhibits osteoclastogenesis and is widely used to prevent osteoporosis; however, evidence on local zoledronate application is controversial due to osteoblast cytotoxicity, uncontrolled dosing regimens, and local release methods. We investigated the effects of zolendronate on osteoclastogenesis and osteogenesis and explored the corresponding signaling pathways. In vitro cytotoxicity and differentiation of MC3T3E1 cells, rat bone marrow stromal cells (BMSCs) and preosteoclasts (RAW264.7 cells) were evaluated with different zolendronate concentrations. In vivo bone regeneration ability was tested by transplanting different concentrations of zolendronate with β-tricalcium phosphate (TCP) bone substitute into rat femoral critical-sized bone defects. In vitro, zolendronate concentrations below 2.5 × 10-7 M did not compromise viability in the three cell lines and did not promote osteogenic differentiation in MC3T3E1 cells and BMSCs. In RAW264.7 cells, zoledronate inhibited extracellular regulated protein kinases and c-Jun n-terminal kinase signaling, downregulating c-Fos and NFATc1 expression, with reduced expression of fusion-related dendritic cell‑specific transmembrane protein and osteoclast-specific Ctsk and tartrate-resistant acid phosphatase (. In vivo, histological staining revealed increased osteoid formation and neovascularization and reduced fibrotic tissue with 500 μM and 2000 μM zolendronate. More osteoclasts were found in the normal saline group after 6 weeks, and sequential osteoclast formation occurred after zoledronate treatment, indicating inhibition of bone resorption during early callus formation without inhibition of late-stage bone remodeling. In vivo, soaking β-TCP artificial bone with 500 μM or 2000 μM zoledronate is a promising approach for bone regeneration, with potential applications in bone transplantation.

Design, synthesis, antibacterial activity evaluation and molecular docking study of pleuromutilin derivatives bearing amide side chains

A seize of pleuromutilin derivatives containing amide side chains were designed and synthesized as potential antibiotics against Methicillin-resistant Staphylococcus aureus (MRSA). Among all target compounds (compounds 11-30), compound 25 was found to have the strongest antibacterial activity against MRSA (minimum inhibitory concentration = 0.5 μg/ml). The result of the time-kill curves indicated that compound 25 could repress the growth of MRSA in vitro obviously (-3.72 log10 CFU/ml reduction). Furthermore, molecular docking studies demonstrated that compound 25 was localized in the binding pocket of 50S ribosomal subunit (ΔGb = -8.99 kcal/mol). Besides, compound 25 displayed low cytotoxicity to RAW 264.7 cells. The results suggested that compound 25 might be further developed into a novel antimicrobial agent against MRSA.