Targeted co-delivery of rapamycin and oxaliplatin by liposomes suppresses tumor growth and metastasis of colorectal cancer.

The activation of tumor cell immunogenicity through oxaliplatin (OXP)-induced immunogenic cell death (ICD) has significant implications in cancer treatment. However, the anti-tumor effect of OXP monotherapy still has many shortcomings, and the systemic administration of OXP leads to low drug concentration at the tumor site, which is susceptible to systemic toxic side effects. In this study, a combined therapeutic strategy using folate-modified nanoliposomes co-delivered with rapamycin (Rapa) and OXP (abbreviated as FA@R/O Lps) is proposed for the treatment of colorectal cancer (CRC). Rapa and OXP can directly inhibit tumor cell proliferation and induce apoptosis. OXP induces ICD by triggering the release of danger signals, such as HMGB1, ATP, and calreticulin. FA@R/O Lps with a particle size of about 134.1±1.8 nm and a small dispersion were successfully prepared. This novel liposomal system can be used to target and increase drug accumulation in tumors. In-vivo experiments showed that FA@R/O Lps successfully inhibit CRC growth and liver metastasis, and simultaneously reduce off-target toxicity. In particular, FA@R/O Lps showed greater therapeutic effects than free Rapa/OXP and R/O Lps. Taken together, this study provides a novel combination of Rapa and OXP, and a nano-delivery system for enhanced anti-CRC efficacy. The results suggest that FA@R/O Lps could be a promising strategy for the treatment of CRC.

Rapamycin circumvents anti PD-1 therapy resistance in colorectal cancer by reducing PD-L1 expression and optimizing the tumor microenvironment.

The unresectable or postoperative recurrence of advanced metastatic colorectal cancer (CRC) is the difficulty of its clinical management, and pharmacological therapy is the main source of benefit. Immune checkpoint inhibitors are therapeutic options but are effective in approximately 5 % of patients with deficient mismatch repair (MMR)/microsatellite instability CRC and are ineffective in patients with MMR-proficient (pMMR)/microsatellite stable (MSS) CRCs, which may be associated with the tumor microenvironment (TME). Here, we propose a new combination strategy and evaluate the efficacy of rapamycin (Rapa) combined with anti-PD-1 (αPD-1) in CT26 tumor-bearing mice, azoxymethane (AOM)/dextran sodium sulfate (DSS) inflammation-associated CRC mice, CT26-Luc tumor-bearing mice with postoperative recurrence, and CT26 liver metastasis mice. The results revealed that Rapa improved the therapeutic effect of αPD-1 and effectively inhibited colorectal carcinogenesis, postoperative recurrence, and liver metastasis. Mechanistically, Rapa improved the anticancer effect of αPD-1, associated with Rapa reprograming of the immunosuppressive TME. Rapa effectively depleted α-SMA+ cancer-associated fibroblasts and degraded collagen in the tumor tissue, increasing T lymphocyte infiltration into the tumor tissue. Rapa induced the downregulation of programed cell death 1 ligand 1 (PD-L1) protein and transcript levels in CT26 cells, which may be associated with the inhibition of the mTOR/P70S6K signaling axis. Furthermore, co-culture of tumor cells and CD8+ T lymphocytes demonstrated that Rapa-induced PD-L1 downregulation in tumor cells increased spleen-derived CD8+ T lymphocyte activation. Therefore, Rapa improves the anti-tumor effect of αPD-1 in CRCs, providing new ideas for its use to improve combinatorial strategies for anti-PD-1 immunotherapy.

Selenium-Doped Nanoheterojunctions for Highly Efficient Cancer Radiosensitization.

Exploring efficient and low-toxicity radiosensitizers to break through the bottleneck of radiation tolerance, immunosuppression and poor prognosis remains one of the critical developmental challenges in radiotherapy. Nanoheterojunctions, due to their unique physicochemical properties, have demonstrated excellent radiosensitization effects in radiation energy deposition and in lifting tumor radiotherapy inhibition. Herein, they doped selenium (Se) into prussian blue (PB) to construct a nano-heterojunction (Se@PB), which could promote the increase of Fe2+/Fe3+ ratio and conversion of Se to a high valence state with Se introduction. The Fe2+-Se-Fe3+ electron transfer chain accelerates the rate of electron transfer on the surface of the nanoparticles, which in turn endows it with efficient X-ray energy transfer and electron transport capability, and enhances radiotherapy physical sensitivity. Furthermore, Se@PB induces glutathione (GSH) depletion and Fe2+ accumulation through pro-Fenton reaction, thereby disturbs the redox balance in tumor cells and enhances biochemical sensitivity of radiotherapy. As an excellent radiosensitizer, Se@PB effectively enhances X-ray induced mitochondrial dysfunction and DNA damage, thereby promotes cell apoptosis and synergistic cervical cancer radiotherapy. This study elucidates the radiosensitization mechanism of Se-doped nanoheterojunction from the perspective of the electron transfer chain and biochemistry reaction, which provides an efficient and low-toxic strategy in radiotherapy.

Nanoliposomes Encapsulated Rapamycin/Resveratrol to Induce Apoptosis and Ferroptosis for Enhanced Colorectal Cancer Therapy.

OBJECTIVES: Monotherapy is often ineffective for treating colorectal cancer. In this study, we developed PEG-modified liposomes loaded with rapamycin (Rapa) and resveratrol (Res) (Rapa/Res liposomes, or RRL) to investigate their therapeutic potential in colorectal cancer. METHODS: RRL were constructed using the reversed-phase evaporation method. We assessed the cytotoxicity, apoptosis, and ferroptotic effects of RRL on colorectal cancer HCT116 cells. The anti-tumor efficacy of RRL was evaluated in HCT116 xenograft mice. RESULTS: RRL had a particle size of 86.67 ± 1.10 nm and a zeta potential of -33.13 ± 0.49 mV. The coloaded formulation demonstrated satisfactory performance both in vitro and in vivo, resulting in increased cytotoxicity to HCT116 cells and significant suppression of HCT116 xenografts tumor growth. Mechanically, RRL significantly increased the apoptosis rate of HCT116 cells, induced ROS accumulation in tumor cells, and effectively downregulated the expression of the ferroptosis-associated proteins GPX4 and SLC7A11, demonstrating its superior efficacy compared to that of Rapa liposomes (Rapa/Lps) or Res liposomes (Res/Lps) alone. CONCLUSION: Coloading Rapa and Res into liposomes to promote apoptosis and ferroptosis in tumor cells represents a promising strategy for the treatment of colorectal cancer.

Isoquercitrin attenuates the progression of non-alcoholic steatohepatitis in mice by modulating galectin-3-mediated insulin resistance and lipid metabolism.

BACKGROUND: Non-alcoholic steatohepatitis (NASH) is a global health problem with no effective treatment. Isoquercitrin (IQ) alters hepatic lipid metabolism and inhibits adipocyte differentiation. The underlying regulatory mechanisms of IQ in regulating insulin resistance (IR) and lipid metabolism remain unclear. PURPOSE: This study was aimed at investigating the effects of IQ on NASH and deciphering whether the underlying mechanisms are via modulation of galectin-3 mediated IR and lipid metabolism. METHODS: IR-HepG2 cell lines were used to demonstrate the ability of IQ to modulate galectin-3-mediated glucose disposal and lipid metabolism. A 20-week high-fat diet (HFD)-induced NASH model was established in C57BL/6J mice, and the protective effect of IQ on lipid disposal in the liver was verified. Further, the mRNA and protein levels of glucose and lipid metabolism were investigated, and lysophosphatidylcholine (LPC) and acylcarnitine (AC) profiling were performed to characterize the changes in endogenous substances associated with mitochondrial function and lipid metabolism in serum and cells. Furthermore, the pharmacokinetic features of IQ were explored in a rat model of NASH. RESULTS: IQ restored liver function and ameliorated inflammation and lipid accumulationin NASH model mice. Notably, significant regulation of the proteins included fatty acid-generating and transporting, cholesterol metabolism enzymes, nuclear transcription factors, mitochondrial metabolism, and IR-related enzymes was noted to be responsible for the therapeutic mechanisms of IQ against experimental NASH. Serum lipid metabolism-related metabolomic assay confirmed that LPC and AC biosynthesis mostly accounted for the therapeutic effect of IQ in mice with NASH and that IQ maintained the homeostasis of LPC and AC levels. CONCLUSION: This is the first study showing that IQ protects against of NASH by modulating galectin-3-mediated IR and lipid metabolism. The mechanisms responsible for liver protection and improved lipid metabolic disorder by IQ may be related to the suppression of IR and regulation of mitochondrial function and lipid metabolism. Galectin-3 down-regulation represents a potentially novel approach for the treatment and prevention of NASH.

Stromal and tumor immune microenvironment reprogramming through multifunctional cisplatin-based liposomes boosts the efficacy of anti-PD-1 immunotherapy in pancreatic cancer.

The dense stromal barrier in pancreatic cancer tissues blocks intratumoral delivery and distribution of chemotherapeutics and therapeutic antibodies, causing poor chemoimmunotherapy responses. We designed a multi-targeted pH-sensitive liposome which encapsulates cisplatin (Pt) in its water core (denoted as ATF@Pt Lps) and shows high affinity for uPAR receptors in pancreatic cancer cells, tumor-associated macrophages, and cancer-associated fibroblasts. Systemic administration of ATF@Pt Lps enabled overcoming the central stromal cellular barrier and effective drug delivery into tumor cells, resulting in a strong therapeutic response in a Panc02 cell derived transplanted tumor mouse model. More importantly, ATF@Pt Lps degradation of collagen contributes to the infiltration of CD8+ T cells into tumors as well as an enhanced accumulation of anti PD-1 monoclonal antibodies. Furthermore, the killing of tumor cells by Pt also leads to the release of tumor antigens, which promote the proliferation of immune cells, especially CD83+ cells, Th1 CD4+ cells, and CD8+ cytotoxic T cells, that converted an immunoscore "cold" pancreatic cancer into a pro-immune "hot" tumor. A further combination with an immune checkpoint agent, anti PD-1 antibodies that inhibit PD-1, can enhance tumor specific cytotoxic T cell response. Accordingly, ATF@Pt Lps displays multi-targeting, controlled drug release, stromal disruption, enhanced penetration, killing of cancer cells, modification of the immunosuppressive microenvironment, and enhancement of immunity. This study provides important mechanistic information for the further development of a combination of ATF@Pt Lps and anti PD-1 antibodies for the effective treatment of pancreatic cancer.

High rapamycin-loaded hollow mesoporous Prussian blue nanozyme targets lesion area of spinal cord injury to recover locomotor function.

Scavenging free radicals and reducing inflammatory reaction to relieve the secondary damage are important issues in the spinal cord injury (SCI) therapeutic strategy. Nanozymes attract more attention in the drug development of SCI due to the high stability, long-lasting catalytic capacity, and multienzyme-like properties. Herein, we constructed a Rapamycin (Rapa)-loaded and hollow mesoporous Prussian blue (HMPB)-based nanozyme (RHPAzyme) to realize the combined antioxidation and anti-inflammation combination therapy of SCI. Furthermore, activated cell penetrating peptide (ACPP) is modified onto nanozyme to endow the effectively ability of lesion area-targeting. This RHPAzyme exhibits ROS scavenging capacity with the transformation of Fe2+/Fe3+ valance and cyanide group of HMPB to achieve multienzyme-like activity. As expected, RHPAzyme scavenges the ROS overproduction and reduces inflammation in oxygen-glucose deprivation (OGD)-induced damage via inhibiting MAPK/AKT signaling pathway. Furtherly, RHPAzyme exhibits the combined antioxidant and anti-inflammatory activity in vivo, which can effectively alleviate neuronal damage and promote motor function recovery in SCI mice. Overall, this study demonstrates the RHPAzyme induces an effective treatment of SCI by inhibiting oxygen-mediated cell apoptosis and suppressing inflammation-induced injury, thus reduces the nervous impairment and promotes motor function recovery.

Amino acid metabolism dysregulation associated with inflammation and insulin resistance in HIV-infected individuals with metabolic disorders.

Amino acid metabolic profile, particularly its association with clinical characteristics, remains unclear in patients with human immunodeficiency virus (HIV) infection and acquired immune deficiency syndrome (AIDS) combined with metabolic disorders. In this study, we performed targeted metabolomic analyses on 64 patients with HIV/AIDS and 21 healthy controls. Twenty-four amino acids and selected intermediate metabolites in the serum were quantitatively detected using high-performance liquid chromatography-tandem mass spectrometry, and characteristic changes and metabolic pathways were analyzed in HIV-infected patients with different degrees of abnormal glucose and lipid metabolism. Spearman's partial correlation was used to analyze the association between amino acids, biochemical parameters, and inflammatory cytokines. The results showed that the main metabolic pathways of the eighteen differential metabolites involved were arginine biosynthesis and metabolism, methionine cycle, and tryptophan metabolism. Fourteen differential amino acid metabolites were positively correlated with nine inflammatory cytokines, including TNF-α, C-reactive protein, IL-1ß, and galectin-3 (FDR < 0.1). Kynurenine, ornithine, and homocysteine were positively correlated with fasting blood glucose and insulin resistance index (FDR < 0.1). Our study revealed a multi-pathway imbalance in amino acid metabolism in patients with HIV/AIDS, which was significantly correlated with inflammation and insulin resistance.

Multi-targeting liposomal codelivery of cisplatin and rapamycin inhibits pancreatic cancer growth and metastasis through stromal modulation.

Pancreatic cancer treatment faces challenges due to drug resistance as well as liver metastasis. As a new strategy for treating pancreatic cancer, combination therapy is now available, but the dense mesenchymal barrier in the tumor tissue blocks drug delivery and impairs its therapeutic efficacy. To address this issue, we prepared an ATF peptide-decorated liposomal co-loaded with cisplatin and rapamycin (ATF@Pt/Rapa Lps), which targets both tumor cells and cancer-associated fibroblasts that express uPAR receptors. In tumor sphere penetration experiments, ATF peptide modified liposomes significantly enhanced deep penetration. More importantly, the ATF@Pt/Rapa Lps disrupted the stroma, as demonstrated by the downregulation of ɑ-SMA, I collagen, and fibronectin protein in vivo and in vitro. In this way, highly effective drug delivery to tumor cells can be achieved. As expected, there was a stronger inhibition of cell proliferation and migration by ATF@Pt/Rapa Lps in vitro compared to free Pt/Rapa and Pt/Rapa Lps. Furthermore, ATF@Pt/Rapa Lps showed greater therapeutic effects in PANC02 transplanted tumor mice and liver metastasis mice models. Ultimately, multi-targeting nanomedicines co-loaded with Rapa and cisplatin may provide a new approach to treating metastatic pancreatic cancer.

Effective Attenuation of Arteriosclerosis Following Lymphatic-Targeted Delivery of Hyaluronic Acid-Decorated Rapamycin Liposomes.

Background: The activation of lymphatic vessel function is the crux to resolving atherosclerosis (AS), a chronic inflammatory disease. Rapamycin (RAPA) recently has attracted considerable attention as a potent drug to induce atherosclerotic plaque attenuation. The objective of this work was to develop a ligand-decorated, RAPA-loaded liposome for lymphatic-targeted delivery of drugs to improve abnormal lymphatic structure and function, resulting in highly effective regression of atherosclerotic plaques. Methods: Hyaluronic acid-decorated, RAPA-loaded liposomes (HA-RL) were fabricated by emulsion-solvent evaporation. The average size, zeta potential, entrapment efficiency were characterized, and the stability and drug release in vitro were investigated. Furthermore, the in vitro and in vivo lymphatic targeting ability were evaluated on lymphatic endothelial cells and LDLR-/- mice, and the efficiency of this nano-system in inducing the attenuation of atherosclerotic plaques was confirmed. Results: HA-RL had a size of 100 nm, over 90% drug encapsulation efficiency, the storage stability was distinguished, demonstrating a slow release from the lipid nano-carriers. The mean retention time (MRT) and elimination half-life (t1/2ß) achieved from HA-RL were 100.27±73.08 h and 70.74±50.80 h, respectively. HA-RL acquired the most prominent efficacy of lymphatic-targeted delivery and atherosclerotic plaques attenuation, implying the successful implementation of this novel drug delivery system in vivo. Conclusion: HA-RL exhibited the most appreciable lymphatic targeting ability and best atherosclerotic plaques attenuation efficiency, opening a new paradigm and promising perspective for the treatment of arteriosclerosis.

Penumbra-targeted CircOGDH siRNA-loaded nanoparticles alleviate neuronal apoptosis in focal brain ischaemia.

BACKGROUND: Nanoparticles (NPs) are a class of substances that can be loaded with therapeutic agents delivered to specific areas. In our earlier research, we identified a neuron-derived circular RNA (circRNA), circular oxoglutarate dehydrogenase (CircOGDH), as a promising therapeutic target for acute ischaemic stroke. This study dedicated to explore a prospective preliminary strategy of CircOGDH-based NP delivered to the ischaemic penumbra region in middle cerebral artery occlusion/reperfusion (MCAO/R) mice. METHODS: Immunofluorescence in primary cortex neurons and in vivo fluorescence imaging revealed endocytosis of Poly(lactide-co-glycolide) (PLGA) poly amidoamine(PAMAM)@CircOGDH small interfering RNA (siRNA) NPs. Western blotting analysis and CCK8 assay were performed to evaluate the apoptotic level in ischaemic neurons treated with PLGA-PAMAM@CircOGDH siRNA NPs. Quantitative reverse transcription PCR experiments, mice behaviour test, T2 MRI analysis, Nissl and TdT-mediated dUTP nick end labeling (TUNEL) co-staining were performed to evaluate the apoptosis level of ischaemic penumbra neurons in MCAO/R mice. Biosafety evaluation of NPs in MCAO/R mice was detected by blood routine examination, liver and kidney function examination and HE staining. RESULTS: PLGA-PAMAM@CircOGDH siRNA NPs were successfully assembled. Endocytosis of PLGA-PAMAM@CircOGDH siRNA NPs in ischaemic neurons alleviated neuronal apoptotic level in vitro and in vivo. Furthermore, mice behaviour test showed that the neurological defects of MCAO/R mice were significantly alleviated after the tail injection of PLGA-PAMAM@CircOGDH siRNA NPs, and no toxic effects were observed. CONCLUSION: In conclusion, our results suggest that PLGA-PAMAM@CircOGDH siRNA NPs can be delivered to the ischaemic penumbra region and alleviate neuron apoptosis in MCAO/R mice and in ischaemic neurons; therefore, our study provides a desirable approach for using circRNA-based NPs for the treatment of ischaemic stroke.

Isoorientin reverses lung cancer drug resistance by promoting ferroptosis via the SIRT6/Nrf2/GPX4 signaling pathway.

Cisplatin, or DDP, is a highly successful and well-known chemotherapy drug used to treat cancer. Acquired resistance to chemotherapy is a major clinical concern, yet the mechanisms of this resistance are still unknown. Ferroptosis is a type of cell death distinct from other forms, fueled by a buildup of iron-associated lipid reactive oxygen species (ROS). Gaining insight into the process of ferroptosis could lead to novel treatments for overcoming cancer resistance. In this study, the combination of isoorientin (IO) and DDP treatment resulted in a significant decrease in the viability of drug-resistant cells, a substantial increase in intracellular iron, malondialdehyde (MDA) and ROS concentrations, a notable decrease in glutathione concentration, and the occurrence of ferroptosis in cells, as revealed by in vitro and in vivo experiments. Additionally, there was a decrease in the expression of nuclear factor-erythroid factor 2-related factor 2 (Nrf2), glutathione peroxidase 4 (GPX4), and sirtuin 6 (SIRT6) proteins, and an increase in cellular ferroptosis. Isoorientin acts as a mediator to regulate cellular ferroptosis and reverse drug resistance in lung cancer cells by controlling the SIRT6/Nrf2/GPX4 signaling pathway. The findings of this study suggest that IO can promote ferroptosis and reverse drug resistance in lung cancer through the SIRT6/Nrf2/GPX4 signaling pathway, thus offering a theoretical basis for its potential clinical application.

X-ray sensitive selenium-containing Ru complexes sensitize nasopharyngeal carcinoma cells for radio/chemotherapy.

Radiotherapy has been extensively applied to cancer therapy in clinical trials. However, radiation resistance and dose limitation generally hamper the efficacy of radiotherapy. There is an urgent need for radiosensitizers with high efficiency and safety to enhance the anti-tumor effect of radiotherapy. In this paper, a selenium-containing (Se) ruthenium (Ru) complex (RuSe) was designed as a radiosensitizer to synergistically augment the killing effect of radiotherapy on nasopharyngeal carcinoma cells. In this system, the heavy atomic effect of Ru enhances the photoelectron production triggered by X-rays, thus inducing a burst of reactive oxygen species (ROS). In addition, Se atoms with a strong polarization property were introduced into the ligand of the metal complex to enhance the tumor chemo/radiotherapy effect. Consequently, RuC with a weak atomic polarization effect, as a comparison for RuSe, was also rationally explored to elucidate the role of Se atoms on chemo/radiotherapy sensitization. Indeed, compared with RuC, RuSe at a sub-toxic dose was able to potentiate the lethality of radiotherapy after preconditioning with cancer cells, by inducing ROS over-production, decreasing the mitochondrial membrane potential, and arresting the cell cycle at the sub-G1 phase. Furthermore, upon radiation, RuSe was superior to RuC, by inducing apoptotic cell death by activating caspase-3, -8, and -9. In summary, this study not only demonstrates an effective and safe strategy for the application of RuSe complexes to the cancer-targeted chemo/radiotherapy of human cancers, but also sheds light on the potential mechanisms of such Se-containing drugs as efficient radiotherapy sensitizers.

Ferulic acid alleviates high fat diet-induced cognitive impairment by inhibiting oxidative stress and apoptosis.

Cognitive impairment has become a major public health problem. Growing evidence suggests that high-fat diet (HFD) can cause cognitive dysfunction and increase the risk of dementia. However, effective treatment for cognitive impairment is not available. Ferulic acid (FA) is a single phenolic compound with anti-inflammatory and antioxidant properties. Nevertheless, its role in regulating learning and memory in HFD-fed mice and the underlying mechanism remains unclear. In this study, we aimed to identify the neuroprotective mechanisms of FA in HFD induced cognitive impairment. We found that FA improved the survival rate of HT22 cells treated with palmitic acid (PA), inhibited cell apoptosis, and reduced oxidative stress via the IRS1/PI3K/AKT/GSK3ß signaling pathway; Furthermore, FA treatment for 24 weeks improved the learning and memory of HFD-fed mice and decreased hyperlipidemia. Moreover, the expression of Nrf2 and Gpx4 proteins were decreased in HFD-fed mice. After FA treatment, the decline of these proteins was reversed. Our study showed that the neuroprotective effect of FA on cognitive impairment was related to the inhibition of oxidative stress and apoptosis and regulation of glucose and lipid metabolism. These findings suggested that FA can be developed as a potential agent for the treatment of HFD-induced cognitive impairment.

Evaluation of characteristic metabolites of aromatic amino acids in patients with HIV infection at different stages of disease.

BACKGROUND: Acquired immune deficiency syndrome (AIDS), human immunodeficiency virus (HIV) infection, and antiretroviral therapy are usually associated with metabolic disorders. Screening for biomarkers to evaluate the progression of metabolic disorders is important for the diagnosis and treatment of HIV infection. This study aimed to establish and validate a method to quantify serum aromatic amino acid (AAA) metabolites as biomarkers of metabolic disorders in patients with HIV. METHODS: The AAAs and metabolites were analyzed using high-performance liquid chromatography-tandem mass spectrometry. Pearson's correlation, heatmap, and receiver operating characteristic curve analyses were used for statistical analysis. RESULTS: Under optimal detection conditions, the lower limits of phenylalanine (Phe), tryptophan (Trp), kynurenine (Kyn), tyrosine, phenylacetylglutamine (PAGln), and 5-hydroxytryptamine quantification reached 0.02, 0.02, 0.01, 0.02, 0.01, and 0.002 µg/ml, respectively, and the precision of intra- and inter-day was stay below 10.30%. Serum samples were stable for at least 6 months when stored at -80°C. The inter-group differences and associations between the biomarkers exhibited a particular volatility trend in PAGln, Trp, and Kyn metabolism in HIV-infected patients with metabolic syndrome. CONCLUSIONS: The developed method can be used for rapid and sensitive quantification of the AAA metabolism profile in vivo to further appraise the process of HIV infection, evaluate intervening measures, conduct mechanistic investigations, and further study the utility of PAGln, a characteristic metabolite of AAA, as a biomarker of HIV infection coupled with metabolic syndrome.

Correction: Selenium-driven enhancement of synergistic cancer chemo-/radiotherapy by targeting nanotherapeutics.

Correction for 'Selenium-driven enhancement of synergistic cancer chemo-/radiotherapy by targeting nanotherapeutics' by Xinxin Liu et al., Biomater. Sci., 2021, 9, 4691-4700, https://doi.org/10.1039/d1bm00348h.

Effective prediction of potential ferroptosis critical genes in clinical colorectal cancer.

Background: Colon cancer is common worldwide, with high morbidity and poor prognosis. Ferroptosis is a novel form of cell death driven by the accumulation of iron-dependent lipid peroxides, which differs from other programmed cell death mechanisms. Programmed cell death is a cancer hallmark, and ferroptosis is known to participate in various cancers, including colon cancer. Novel ferroptosis markers and targeted colon cancer therapies are urgently needed. To this end, we performed a preliminary exploration of ferroptosis-related genes in colon cancer to enable new treatment strategies. Methods: Ferroptosis-related genes in colon cancer were obtained by data mining and screening for differentially expressed genes (DEGs) using bioinformatics analysis tools. We normalized the data across four independent datasets and a ferroptosis-specific database. Identified genes were validated by immunohistochemical analysis of pathological and healthy clinical samples. Results: We identified DEGs in colon cancer that are involved in ferroptosis. Among these, five core genes were found: ELAVL1, GPX2, EPAS1, SLC7A5, and HMGB1. Bioinformatics analyses revealed that the expression of all five genes, except for EPAS1, was higher in tumor tissues than in healthy tissues. Conclusions: The preliminary exploration of the five core genes revealed that they are differentially expressed in colon cancer, playing an essential role in ferroptosis. This study provides a foundation for subsequent research on ferroptosis in colon cancer.

The combination of Lonicerae Japonicae Flos and Forsythiae Fructus herb-pair alleviated inflammation in liver fibrosis.

Objective: To explore the active components and epigenetic regulation mechanism underlying the anti-inflammatory effects of Lonicerae Japonicae Flos and Forsythiae Fructus herb-pair (LFP) in carbon tetrachloride (CCl4)-induced rat liver fibrosis. Methods: The main active ingredients and disease-related gene targets of LFP were determined using TCMSP and UniProt, and liver fibrosis disease targets were screened in the GeneCards database. A network was constructed with Cytoscape 3.8.0 and the STRING database, and potential protein functions were analyzed using bioinformatics analysis. Based on these analyses, we determined the main active ingredients of LFP and evaluated their effects in a CCl4-induced rat liver fibrosis model. Serum biochemical indices were measured using commercial kits, hepatocyte tissue damage and collagen deposition were evaluated by histopathological studies, and myofibroblast activation and inflammation were detected by reverse transcription-polymerase chain reaction (RT-PCR) and western blotting. High-performance liquid chromatography-mass spectrometry was performed to determine the levels of homocysteine, reduced glutathione, and oxidized glutathione, which are involved in inflammation and oxidative stress. Results: The main active components of LFP were quercetin, kaempferol, and luteolin, and its main targets were α-smooth muscle actin, cyclooxygenase-2, formyl-peptide receptor-2, prostaglandin-endoperoxide synthase 1, nuclear receptor coactivator-2, interleukinß, tumor necrosis factor α, CXC motif chemokine ligand 14, and transforming growth factor ß1. A combination of quercetin, kaempferol, and luteolin alleviated the symptoms of liver fibrosis. Conclusion: The results of this study support the role of LFP in the treatment of liver fibrosis, and reveal that LFP reduces collagen formation, inflammation, and oxidative stress. This study suggests a potential mechanism of action of LFP in the treatment of liver fibrosis.

Differential proteomic analysis of mouse cerebrums with high-fat diet (HFD)-induced hyperlipidemia.

Hyperlipidemia is a chronic disease characterized by elevated blood cholesterol and triglycerides and there is accumulated evidence that the disease might affect brain functions. Here we report on a proteomic analysis of the brain proteins in hyperlipidemic mice. Hyperlipidemia was successfully induced in mice by a 20 week high-fat diet (HFD) feeding (model group). A control group with a normal diet and a treatment group with HFD-fed mice treated with a lipid-lowering drug simvastatin (SIM) were established accordingly. The proteins were extracted from the left and right cerebrum hemispheres of the mice in the three groups and subjected to shotgun proteomic analysis. A total of 4,422 proteins were detected in at least half of the samples, among which 324 proteins showed significant difference (fold change >1.5 or <0.67, p < 0.05) in at least one of the four types of comparisons (left cerebrum hemispheres of the model group versus the control group, right cerebrums of model versus control, left cerebrums of SIM versus model, right cerebrums of SIM versus model). Biological process analysis revealed many of these proteins were enriched in the processes correlated with lipid metabolism, neurological disorders, synaptic events and nervous system development. For the first time, it has been reported that some of the proteins have been altered in the brain under the conditions of HFD feeding, obesity or hyperlipidemia. Further, 22 brain processes-related proteins showed different expression in the two cerebrum hemispheres, suggesting changes of the brain proteins caused by hyperlipidemia might also be asymmetric. We hope this work will provide useful information to understand the effects of HFD and hyperlipidemia on brain proteins.

In situ-transition nanozyme triggered by tumor microenvironment boosts synergistic cancer radio-/chemotherapy through disrupting redox homeostasis.

Disrupting redox homeostasis in the tumor microenvironment (TME), like excessive H2O2, glutathione (GSH) and weak acidity, has been proved as an effective tumor therapeutic strategy. Herein, we constructed a TME-responsive nanozyme, DOX@HMSN/Mn3O4(R), with reversible Mn3+/Mn2+ transition in situ triggered by TME to perturb the intrinsic redox homeostasis and catalyze reactive oxygen species (ROS) overproduction. In addition, this nanozyme could react with excess GSH in TME to produce GSSG, resulting in the consumption of reducing agents to suppress ROS clearance. Density functional theory calculations further confirmed that the nanozyme mainly exhibited the oxidase-like activity to catalyze the formation of hydroxyl radicals from O2, thus strengthening the oxidation environment in the TME. Combined with radiotherapy, the high-energy X-ray could excite the outer-layer electrons in the nanozyme, forming photoelectrons that participate in the oxidase-like enzymatic reaction, thus intensifying ROS accumulation and amplifying the radio-/chemotherapeutic efficacy.