Reaction targets of antioxidants in azo-initiator or lipid hydroperoxide induced lipid peroxidation

Regulation of antigen presentation and interleukin 10 production in murine dendritic cells via the oxidative stimulation of cell membrane using a polycation-porphyrin-conjugate-immobilized cell culture dish

Tolerogenic dendritic cells with professional antigen presentation via major histocompatibility complex molecules, co-stimulatory molecules (CD80/86), and interleukin 10 production have attracted significant attention as cellular therapies for autoimmune, allergic, and graft-versus-host diseases. In this study, we developed a cell culture dish equipped with polycation-porphyrin-conjugate-immobilized glass (PA-HP-G) to stimulate immature murine dendritic cell (iDCs). Upon irradiation with a red light at 635 nm toward the PA-HP-G surface, singlet oxygen was generated by the immobilized porphyrins on the PA-HP-G surface. When iDCs were cultured on the PA-HP-G surface, moderate light irradiation generated lipid radicals without excessive generation of reactive oxygen species in the cytoplasm and nucleus, which led to the oxidative stimulation of the iDC cell membrane without cell death. Light irradiation changed the morphology of dendritic cells on the PA-HP-G surface to a tree-like structure with dendrites, accelerated their maturation, and enhanced the antigen-presenting ability for the ovalbumin peptide via major histocompatibility complex class I molecules. Additionally, the antigen-presenting dendritic cells on the PA-HP-G surface produced the anti-inflammatory cytokine interleukin 10 upon light irradiation. These results indicated that upon moderate light irradiation, the PA-HP-G surface regulated the maturation of iDCs into tolerogenic dendritic cells. STATEMENT OF SIGNIFICANCE: • Cell culture dish is developed for selective oxidative stimulus of cell membrane. • 1O2 is generated from polycation/porphyrin-immobilized glass by light irradiation. • Lipid radicals are generated without generation of ROS in cytoplasm and nuclei. • Immature dendritic cells are maturated by oxidative stimulation of cell membrane. • Oxidative membrane stimulus enhances antigen-presentation and IL-10 secretion.

Mechanisms and cross-talk of regulated cell death and their epigenetic modifications in tumor progression

Cell death is a fundamental part of life for metazoans. To maintain the balance between cell proliferation and metabolism of human bodies, a certain number of cells need to be removed regularly. Hence, the mechanisms of cell death have been preserved during the evolution of multicellular organisms. Tumorigenesis is closely related with exceptional inhibition of cell death. Mutations or defects in cell death-related genes block the elimination of abnormal cells and enhance the resistance of malignant cells to chemotherapy. Therefore, the investigation of cell death mechanisms enables the development of drugs that directly induce tumor cell death. In the guidelines updated by the Cell Death Nomenclature Committee (NCCD) in 2018, cell death was classified into 12 types according to morphological, biochemical and functional classification, including intrinsic apoptosis, extrinsic apoptosis, mitochondrial permeability transition (MPT)-driven necrosis, necroptosis, ferroptosis, pyroptosis, PARP-1 parthanatos, entotic cell death, NETotic cell death, lysosome-dependent cell death, autophagy-dependent cell death, immunogenic cell death, cellular senescence and mitotic catastrophe. The mechanistic relationships between epigenetic controls and cell death in cancer progression were previously unclear. In this review, we will summarize the mechanisms of cell death pathways and corresponding epigenetic regulations. Also, we will explore the extensive interactions between these pathways and discuss the mechanisms of cell death in epigenetics which bring benefits to tumor therapy.

Lipid radicals and oxidized cholesteryl esters in low- and high-density lipoproteins in patients with β-thalassemia: Effects of iron overload and iron chelation therapy

Iron overload results in lipid peroxidation (LPO) and the oxidative modification of circulating lipoproteins, which contributes to cardiovascular complications in patients with β-thalassemia. Investigating LPO may provide opportunities for the development of novel therapeutic strategies; however, the chemical pathways underlying iron overload-induced LPO in β-thalassemia lipoproteins remain unclear. In this study, we identified various species of lipid radicals (L•), the key mediators of LPO, and oxidized cholesteryl esters (oxCE) derived from the in vitro oxidation of major core lipids, cholesteryl linoleate (CE18:2) and cholesteryl arachidonate (CE20:4); the levels of these radical products in low-density lipoproteins (LDL) and high-density lipoproteins (HDL) were measured and compared between β-thalassemia patients and healthy subjects by using a specific fluorescent probe for L• with a liquid chromatography-tandem mass spectrometric method. Our results demonstrated that iron overload substantially decreased the levels of CE18:2 and CE20:4 substrates and α-tocopherol, resulting in higher levels of full-length and short-chain truncated L• and oxCE products. In particular, CE epoxyallyl radicals (•CE-O) were observed in the lipoproteins of β-thalassemia, revealing the pathological roles of iron overload in the progression of LPO. In addition, we found that intermission for two weeks of iron chelators can increase the production of these oxidized products; therefore, suggesting the beneficial effects of iron chelators in preventing LPO progression. In conclusion, our findings partly revealed the primary chemical pathway by which the LPO of circulating lipoproteins is influenced by iron overload and affected by iron chelation therapy. Moreover, we found that •CE + O shows potential as a sensitive biomarker for monitoring LPO in individuals with β-thalassemia.

Exploring Sorafenib and Simvastatin Combination for Ferroptosis-Induced Cancer Treatment: Cytotoxicity Screening, In Vivo Efficacy, and Safety Assessment

Ferroptosis, a pathway dependent on oxygen and iron catalysts, holds promise as a therapeutic approach for cancer treatment due to its manageable regulation, direct control, and immunogenic properties. The sensitivity of cancer cells to ferroptosis induction varies based on their metabolic, genetic, and signalling pathways, prompting the use of combination therapy. In this study, we conducted a screening of drug combinations, including sorafenib (SOR) with simvastatin (SIM), phenethyl isothiocyanate, and trigonelline, in MDA-MB-231, A549, and HeLa cells to assess their cytotoxicity. The SOR-SIM combination exhibited a synergistic effect in MDA-MB-231, A549, and HeLa cells, with calculated CI values of ~ 0.66, 0.53, and 0.59, respectively. Furthermore, co-treatment with ferrostatin-1 resulted in a concentration-dependent increase in the IC50 values. Additionally, SOR + SIM demonstrated a significant reduction in GSH levels, an increase in MDA levels, and mitochondrial membrane depolarization across all three cell lines, indicating their ferroptosis inducing potential. In-vivo studies showed a significant reduction in tumor volume by 3.53-, 2.55-, and 1.47-fold compared to control, SIM, and SOR, respectively. Toxicity assessments revealed insignificant changes in biomarker levels and no observable deformations in isolated organs, except for erythrocyte shrinkage and membrane scrambling effects caused by the SOR + SIM combination. Overall, our findings highlight the potential of the SOR + SIM combination as an effective strategy for cancer treatment, emphasizing the importance of further research in targeted drug delivery systems to ensure its safety.

Exploring the effect of Yinzhihuang granules on alcoholic liver disease based on pharmacodynamics, network pharmacology and molecular docking

BACKGROUND

Yinzhihuang granules (YZHG) is a commonly used Chinese patent medicine for the treatment of liver disease. However, the mechanism of YZHG in alcoholic liver disease (ALD) is still unclear.

METHODS

This study combined liquid chromatography-mass spectrometry technology, pharmacodynamics, network pharmacology and molecular docking methods to evaluate the potential mechanism of YZHG in the treatment of ALD.

RESULTS

A total of 25 compounds including 4-hydroxyacetophenone, scoparone, geniposide, quercetin, baicalin, baicalein, chlorogenic acid and caffeic acid in YZHG were identified by ultra performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS). The pharmacodynamic investigations indicated that YZHG could improve liver function and the degree of liver tissue lesions, and reduce liver inflammation and oxidative stress in ALD mice. Network pharmacology analysis showed that YZHG treated ALD mainly by regulating inflammation-related signaling pathways such as the PI3K-Akt signaling pathway. The results of the PPI network and molecular docking showed that the targets of SRC, HSP90AA1, STAT3, EGFR and AKT1 could be the key targets of YZHG in the treatment of ALD.

CONCLUSION

This study explored the potential compounds, potential targets and signaling pathways of YZHG in the treatment of ALD, which is helpful to clarify the efficacy and mechanism of YZHG and provide new insights for the clinical application of YZHG.

Cellular mechanisms in brain aging: Focus on physiological and pathological aging

Aging is a natural phenomenon characterized by accumulation of cellular damage and debris. Oxidative stress, cellular senescence, sustained inflammation, and DNA damage are the main cellular processes characteristic of aging associated with morphological and functional decline. These effects tend to be more pronounced in tissues with high metabolic rates such as the brain, mainly in regions such as the prefrontal cortex, hippocampus, and amygdala. These regions are highly related to cognitive behavior, and therefore their atrophy usually leads to decline in processes such as memory and learning. These cognitive declines can occur in physiological aging and are exacerbated in pathological aging. In this article, we review the cellular processes that underlie the triggers of aging and how they relate to one another, causing the atrophy of nerve tissue that is typical of aging. The main topic of this review to determine the central factor that triggers all the cellular processes that lead to cellular aging and discriminate between normal and pathological aging. Finally, we review how the use of supplements with antioxidant and anti-inflammatory properties reduces the cognitive decline typical of aging, which reinforces the hypothesis of oxidative stress and cellular damage as contributors of physiological atrophy of aging. Moreover, cumulative evidence suggests their possible use as therapies, which improve the aging population's quality of life.

Calcium signaling induced by 15-deoxy-prostamide-J2 promotes cell death by activating PERK, IP3R, and the mitochondrial permeability transition pore

Melanoma is the deadliest form of skin cancer in the US. Although immunotherapeutic checkpoint inhibitors and small-molecule kinase inhibitors have dramatically increased the survival of patients with melanoma, new or optimized therapeutic approaches are still needed to improve outcomes. 15-deoxy-Δ^12,14-prostamide J₂ (15d-PMJ₂) is an investigational small-molecule that induces ER stress-mediated apoptosis selectively in tumor cells. Additionally, 15d-PMJ2 reduces melanoma growth in vivo. To assess the chemotherapeutic potential of 15d-PMJ₂, the current study sought to uncover molecular pathways by which 15d-PMJ₂ exerts its antitumor activity. B16F10 melanoma and JWF2 squamous cell carcinoma cell lines were cultured in the presence of pharmacological agents that prevent ER or oxidative stress as well as Ca²⁺ channel blockers to identify mechanisms of 15d-PMJ₂ cell death. Our data demonstrated the ER stress protein, PERK, was required for 15d-PMJ₂-induced death. PERK activation triggered the release of ER-resident Ca²⁺ through an IP₃R sensitive pathway. Increased calcium mobilization led to mitochondrial Ca²⁺ overload followed by mitochondrial permeability transition pore (mPTP) opening and the deterioration of mitochondrial respiration. Finally, we show the electrophilic double bond located within the cyclopentenone ring of 15d-PMJ₂ was required for its activity. The present study identifies PERK/IP3R/mPTP signaling as a mechanism of 15d-PMJ₂ antitumor activity.

Effects of sodium chloride and sodium tripolyphosphate on the prooxidant properties of hemoglobin in washed turkey muscle system

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MetHb in WTM acted as the most effective pro-oxidant, followed by hemin and oxyHb.

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The addition of NaCl significantly increased the oxyHb-mediated lipid oxidation.

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STPP inhibited oxyHb-mediated lipid oxidation.

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Formation of metHb and pH paly critical roles in oxyHb-mediated lipid oxidation.

This study examined the effects of sodium chloride (NaCl) and sodium tripolyphosphate (STPP) on lipid oxidation induced by oxyhemoglobin (oxyHb) in washed turkey muscle (WTM) model. To explore the reasons for observed effects, the pro-oxidant abilities of Hb derivatives (e.g., metHb, oxyHb, hemin, Fe²⁺, and Fe³⁺), pH change, and antioxidation of Hb in the presence of NaCl or STPP were also analyzed. The observed lipid oxidation capacity in WTM followed the order metHb > hemin > oxyHb > Fe²⁺ > Fe³⁺. Added Fe²⁺ accelerated auto-oxidation of oxyHb and oxyHb-mediated lipid oxidation. Hb auto-oxidation to metHb increased as the pH decreased from 6.6 to 5.0. NaCl promoted oxyHb-mediated lipid oxidation due to NaCl causing decreased pH value and increased formation of metHb. STPP inhibited oxyHb-mediated lipid oxidation and weakened the pro-oxidative effect of NaCl. This could be attributed to STPP increasing the pH, inactivating free iron, and inhibiting formation of metHb.

Current trends in smart mesoporous silica-based nanovehicles for photoactivated cancer therapy

Photoactivated therapeutic strategies (photothermal therapy and photodynamic therapy), due to the adjusted therapeutic area, time and light dosage, have prevailed for the fight against tumors. Currently, the monotherapy with limited treatment effect and undesired side effects is gradually replaced by multimodal and multifunctional nanosystems. Mesoporous silica nanoparticles (MSNs) with unique physicochemical advantages, such as huge specific surface area, controllable pore size and morphology, functionalized modification, satisfying biocompatibility and biodegradability, are considered as promising candidates for multimodal photoactivated cancer therapy. Excitingly, the innovative nanoplatforms based on the mesoporous silica nanoparticles provide more and more effective treatment strategies and display excellent antitumor potential. Given the rapid development of antitumor strategies based on MSNs, this review summarizes the current progress in MSNs-based photoactivated cancer therapy, mainly consists of (1) photothermal therapy-related theranostics; (2) photodynamic therapy-related theranostics; (3) multimodal synergistic therapy, such as chemo-photothermal-photodynamic therapy, phototherapy-immunotherapy and phototherapy-radio therapy. Based on the limited penetration of irradiation light in photoactivated therapy, the challenges faced by deep-seated tumor therapy are fully discussed, and future clinical translation of MSNs-based photoactivated cancer therapy are highlighted.