Novel copper-containing ferrite nanoparticles exert lethality to MRSA by disrupting MRSA cell membrane permeability, depleting intracellular iron ions, and upregulating ROS levels.

Objective: The widespread use of antibiotics has inevitably led to the emergence of multidrug-resistant bacterial strains, such as methicillin-resistant Staphylococcus aureus (MRSA), making treatment of this infection a serious challenge. This study aimed to explore new treatment strategies for MRSA infection. Methods: The structure of Fe3O4 NPs with limited antibacterial activity was optimized, and the Fe2+ ↔ Fe3+ electronic coupling was eliminated by replacing 1/2 Fe2+ with Cu2+. A new type of copper-containing ferrite nanoparticles (hereinafter referred to as Cu@Fe NPs) that fully retained oxidation-reduction activity was synthesized. First, the ultrastructure of Cu@Fe NPs was examined. Then, antibacterial activity was determined by testing the minimum inhibitory concentration (MIC) and safety for use as an antibiotic agent. Next, the mechanisms underlying the antibacterial effects of Cu@Fe NPs were investigated. Finally, mice models of systemic and localized MRSA infections was established for in vivo validation. Results: It was found that Cu@Fe NPs exhibited excellent antibacterial activity against MRSA with MIC of 1 µg/mL. It effectively inhibited the development of MRSA resistance and disrupted the bacterial biofilms. More importantly, the cell membranes of MRSA exposed to Cu@Fe NPs underwent significant rupture and leakage of the cell contents. Cu@Fe NPs also significantly reduced the iron ions required for bacterial growth and contributed to excessive intracellular accumulation of exogenous reactive oxygen species (ROS). Therefore, these findings may important for its antibacterial effect. Furthermore, Cu@Fe NPs treatment led to a significant reduction in colony forming units within intra-abdominal organs, such as the liver, spleen, kidney, and lung, in mice with systemic MRSA infection, but not for damaged skin in those with localized MRSA infection. Conclusion: The synthesized nanoparticles has an excellent drug safety profile, confers high resistant to MRSA, and can effectively inhibit the progression of drug resistance. It also has the potential to exert anti-MRSA infection effects systemically in vivo. In addition, our study revealed a unique multifaceted antibacterial mode of Cu@Fe NPs: (1) an increase in cell membrane permeability, (2) depletion of Fe ions in cells, (3) generation of ROS in cells. Overall, Cu@Fe NPs may be potential therapeutic agents for MRSA infections.

High expression of hypoxia-inducible factor 1-alpha predicts poor prognosis in pancreatic ductal adenocarcinoma: a meta-analysis and database validation protocol.

Background: Hypoxia-inducible factor 1-alpha (HIF-1α) is overexpressed in pancreatic ductal adenocarcinomas (PDACs). However, the prognosis of high expression of HIF-1α in PDACs remains controversial because of lacking a solid support. A meta-analysis may help for a better understanding of the role of HIF-1α in the prognosis of PDACs. Methods: By using a systematic approach, we conducted a meta-analysis from current literature. We performed an advanced search in PubMed, Embase, Cochrane Library and Web of Science databases. Recorded studies were published between September 1, 2001, and February 26, 2021, in English and related to the expression of HIF-1α in PDAC. We pooled and combined hazard ratios (HRs) and 95% confidence intervals (CIs) to show the effect of HIF-1α expression on overall survival (OS). We pooled also risk ratios (RRs) and 95% CIs to assess the correlation between HIF-1α expression and clinicopathological characteristics in PDAC. We evaluated publication bias among included studies through the Begg's test and Egger's test. From "Expression Plots" modules in the Gene Expression Profiling Interactive Analysis (GEPIA) database, we showed the difference of mRNA level for HIF1A between 179 pancreatic adenocarcinomas (PAADs) and 171 normal pancreatic tissues. Results: This meta-analysis included 11 studies and 764 patients. High expression of HIF-1α was associated with shorter OS compared to low HIF-1α expression in PDAC (HR =1.74, 95% CI: 1.49-2.04, P<0.001). Patients with high expression of HIF-1α tended to have an increased risk of earlier lymph node metastasis (LNM) (RR =1.63, 95% CI: 1.36-1.95, P<0.001), and more advanced clinical stage (RR =1.64, 95% CI: 1.38-1.97, P<0.001) compared to those with low HIF-1α expression. Expression plots from GEPIA database showed HIF1A overexpressed in PDAC tissues compared to normal tissues (Log2FC =2, P<0.01). Conclusions: High HIF-1α expression associated with worse prognosis of PDACs compared to low HIF-1α expression. Since HIF-1α expression is greater in PDAC than normal pancreas, it could serve as a prognostic factor and potential therapeutic target. However, due to the complex role of HIF-1α in physiology and pathology, therapeutic intervention should be considered with caution.

siAKR1C3@PPA complex nucleic acid nanoparticles inhibit castration-resistant prostate cancer in vitro.

Introduction: AKR1C3, as a crucial androgenic enzyme, implicates the androgen biosynthesis and promoting prostate cancer cell growth in vitro. This study provides a new gene therapy strategy for targeting AKR1C3 to treat castration-resistant prostate cancer. Methods: siAKR1C3@PPA is assembled from PEG3500, PAMAM, Aptamer-PSMA, and siRNA for AKR1C3. We analyzed the relationship between AKR1C3 expression and the survival rate of prostate cancer patients based on the GEPIA online database to perform disease-free survival, and found that AKR1C3 may be an important factor leading to poor prognosis in prostate cancer. Considering AKR1C3 as a therapeutic target for castration-resistant prostate cancer, we constructed a complex nucleic acid nanoparticle, siAKR1C3@PPA to investigate the inhibitory effect on castration-resistant prostate cancer. Results: Aptamer-PSMA acts as a target to guide siAKR1C3@PPA into PSMA-positive prostate cancer cells and specifically down regulate AKR1C3. Cyclin D1 was decreased as a result of siAKR1C3@PPA treatment. Changes in Cyclin D1 were consistent with decreased expression of AKR1C3 in LNCaP-AKR1C3 cells and 22RV1 cells. Furthermore, in the LNCaP-AKR1C3 group, 1070 proteins were upregulated and 1015 proteins were downregulated compared to the LNCaP group according to quantitative 4D label-free proteomics. We found 42 proteins involved in cell cycle regulation. In a validated experiment, we demonstrated that PCNP and CINP were up-regulated, and TERF2 and TP53 were down-regulated by western blotting. Conclusion: We concluded that siAKR1C3@PPA may arrest the cell cycle and affect cell proliferation.

Macrophage depletion protects against endothelial dysfunction and cardiac remodeling in angiotensin II hypertensive mice.

Objective: Hypertension is associated with a low-grade systemic inflammation in cardiovascular system. Macrophage infiltration may initiate an inflammatory process that contributes to vascular and ventricular remodeling in hypertensive human and mice. The present study investigated the effect of chemical depletion of macrophage using liposome encapsulated clodronate (LEC) on cardiac hypertrophy and remodeling in angiotensin (Ang) II hypertensive mice.Methods: C57BL/6 mice received an Ang II (1.1 mg/kg/day with a minipump) infusion for 2 weeks to induce hypertension. Endothelium-dependent relaxation (ED) was examined by organ bath, hematoxylin and staining and Masson-Trichrome staining were used to evaluate aorta and cardiac hypertrophy and fibrosis.Results: Ang II infusion significantly increased systolic blood pressure (SBP), cardiac hypertrophy and fibrosis, and impaired EDR accompanied by increased macrophage infiltration in the heart. Treatment with LEC significantly lowered Ang II-induced cardiac hypertrophy and fibrosis and cardiac macrophage infiltration, and improved EDR with a mild reduction in SBP. Ang II increased the expression of inflammatory cytokines tumor necross factor alpha and interleukin 1 beta and profibrotic factors transforming growth factor beta 1 and fibronectin in the heart, with was reduced by LEC treatment. Treatment with LEC prevented Ang II-induced the phosphorphorylation of ERK1/2 and c-Jun-N-terminal kinase.Conclusions: Our study suggests that cardiac macrophage may be critical for hypertensive cardiac hypertrophy and remodeling, the underlying mechanisms may involve initial heart inflammation and the activation of hypertrophic MAPKs pathway.

Macrophage Depletion Improves Endothelial Insulin Resistance and Protects against Cardiovascular Injury in Salt-Sensitive Hypertension.

Vascular endothelial insulin signaling is critical for the maintenance of vascular and metabolic homeostasis. We have previously shown that in hypertensive Dahl rats, impaired vascular insulin action is linked to angiotensin II activation of the NFκB inflammatory pathway. Macrophage polarization (M1) has implicated in hypertensive and metabolic diseases. Here, we investigated the effect of macrophage depletion using liposome-encapsulated clodronate (LEC) on endothelial insulin resistance and cardiovascular remodeling in Dahl salt-sensitive (DS) rats. High salt intake (HS) for 5 weeks increased systolic blood pressure (SBP: 192 ± 5 vs. 144 ± 4 mmHg in NS, p < 0.05), aortic and cardiac hypertrophy, cardiac fibrosis, and impaired acetylcholine- and insulin-induced vasorelaxation, accompanied by impaired insulin activation of endothelial nitric oxide synthases (eNOS)/NO signaling. HS rats had a significant increase in CD68 (a monocyte/macrophage marker) expression in the aorta and the heart. LEC reduced SBP (168 ± 5 mmHg, p < 0.05) and cardiovascular injury and improved acetylcholine- and insulin-mediated vasorelaxation and insulin signaling molecules with a reduction in the macrophage infiltration in the aorta and the heart. HS rats also manifested an increase in the aortic expressions of inflammatory cytokines, including the ratio of phosphorylated inhibitory kappa B (Iκb)/Iκb, tumor necrosis factor α, and phosphorylated c-Jun N-terminal kinase (JNK) and oxidative stress, which were reduced in HS/LEC rats. Our results suggest that in salt-sensitive hypertension, macrophage may importantly contribute to endothelial insulin resistance, vascular inflammation, and injury. These findings support the idea that macrophages may be a new target for immunotherapy of vasculopathy in hypertensive and metabolic disorders.

Taurine Protects Primary Neonatal Cardiomyocytes Against Apoptosis Induced by Hydrogen Peroxide.

The aim of this study was to investigate the effects of taurine (Tau) on primary cultured neonatal myocardial cells treated with hydrogen peroxide (H2O2) and the underlying mechanism. Primary cardiac myocytes from neonatal Wistar rats were pre-incubated with Tau, and its effects on cell viability and expression of CaM, CaMKII, p53, Bcl-2, and Bax were examined. Tau enhanced the viability of myocardial cells, decreased apoptosis, and alleviated the intracellular calcium overload, especially at dosages of 40 or 80 mM (P < 0.01 or P < 0.001, respectively). Moreover, Tau could inhibit the H2O2-induced decrease in CamKII and CaM expression at both the mRNA and protein levels. The pattern of CaMKII expression was consistent with that of the anti-apoptotic protein Bcl-2, but contrasted the pattern of the pro-apoptotic proteins p53 and Bax. Thus, our results show that Tau protects myocardial cells against damage caused by H2O2 exposure, suggesting that it might play a role in the mitochondrial apoptotic pathway by upregulating the expression of CaMKII to rescue myocardial cells. However, the underlying mechanism still needs to be investigated. In addition, we tested the protective effect of taurine on cardiac myocytes, and the effect of taurine on another model, specifically an animal model.

YCl3 Promotes Neuronal Cell Death by Inducing Apoptotic Pathways in Rats.

The pollutants rare earth elements (REEs) have posed great threats to human health. To investigate the cytotoxicity of yttrium (Y), a model that rats have free access to water containing YCl3 for 6 months is utilized. The results showed that YCl3 treatment promoted neuronal cell apoptosis by upregulating the proapoptotic factors Bax, caspase-3, Cyto c, and DAPK and by downregulating the antiapoptotic factors Bcl-2 and XIAP at both mRNA and protein levels. Conclusively, YCl3 exhibited cytotoxicity and promoted neuronal cell death by the induction of apoptotic pathways.

Berberine inhibits androgen synthesis by interaction with aldo-keto reductase 1C3 in 22Rv1 prostate cancer cells.

Aldo-keto reductase family 1 member C3 has recently been regarded as a potential therapeutic target in castrate-resistant prostate cancer. Herein, we investigated whether berberine delayed the progression of castrate-resistant prostate cancer by reducing androgen synthesis through the inhibition of Aldo-keto reductase family 1 member C3. Cell viability and cellular testosterone content were measured in prostate cancer cells. Aldo-keto reductase family 1 member C3 mRNA and protein level were detected by RT-PCR and Western bolt analyses, respectively. Computer analysis with AutoDock Tools explored the molecular interaction of berberine with Aldo-keto reductase family 1 member C3. We found that berberine inhibited 22Rv1 cells proliferation and decreased cellular testosterone formation in a dose-dependent manner. Berberine inhibited Aldo-keto reductase family 1 member C3 enzyme activity, rather than influenced mRNA and protein expressions. Molecular docking study demonstrated that berberine could enter the active center of Aldo-keto reductase family 1 member C3 and form p-p interaction with the amino-acid residue Phe306 and Phe311. In conclusion, the structural interaction of berberine with Aldo-keto reductase family 1 member C3 is attributed to the suppression of Aldo-keto reductase family 1 member C3 enzyme activity and the inhibition of 22Rv1 prostate cancer cell growth by decreasing the intracellular androgen synthesis. Our result provides the experimental basis for the design, research, and development of AKR1C3 inhibitors using berberine as the lead compound.

The effect of lipocisplatin on cisplatin efficacy and nephrotoxicity in malignant breast cancer treatment.

A lipid-cisplatin conjugate was synthesized for super-molecular assembly with lipids to form a new generation of liposomal cisplatin formulation, lipocisplatin. In vitro, lipocisplatin has higher efficacy in human ovarian cancer A2780 and human breast cancer MCF-7 with the murine breast cancer cell line 4T1 which is currently an established model for stage IV breast cancer as the most sensitive strain. Moreover, lipocisplatin demonstrated a greater MTD value and relatively longer blood circulation as compared to cisplatin. Lipocisplatin preferentially accumulate drugs to the tumor site, resulting in a better tumor inhibition efficacy. Moreover, lipocisplatin exceeds the size cutoff for kidney clearance, hence it bypasses the nephrotoxicity of cisplatin which is a major curse of one of the most efficient anticancer drugs nowadays in clinic. The results here indicated lipocisplatin may be translated into a new generation of liposomal based cisplatin drug in clinic.

AKR1C3 overexpression may serve as a promising biomarker for prostate cancer progression.

BACKGROUND: Aldo-keto reductase family 1 member C3 (AKR1C3) is a key steroidogenic enzyme that is overexpressed in prostate cancer (PCa) and is associated with the development of castration-resistant prostate cancer (CRPC). The aim of this study was to investigate the correlation between the expression level of AKR1C3 and the progression of PCa. METHODS: Sixty human prostate needle biopsy tissue specimens and ten LNCaP xenografts from intact or castrated male mice were included in the study. The relationship between the level of AKR1C3 expression by immunohistochemistry and evaluation factors for PCa progression, including prostate-specific antigen (PSA), Gleason score (GS) and age, were analyzed. RESULTS: Low immunoreactivity of AKR1C3 was detected in normal prostate epithelium, benign prostatic hyperplasia (BPH) and prostatic intraepithelial neoplasia (PIN). Positive staining was gradually increased with an elevated GS in PCa epithelium and LNCaP xenografts in mice after castration. The Spearman's r values (rs) of AKR1C3 to GS and PSA levels were 0.396 (P = 0.025) and -0.377 (P = 0.036), respectively, in PCa biopsies. The rs of AKR1C3 to age was 0.76 (P = 0.011). No statistically significant difference was found with other variables. CONCLUSION: Our study suggests that the level of AKR.1C3 expression is positively correlated with an elevated GS, indicating that AKR1C3 can serve as a promising biomarker for the progression of PCa. VIRTUAL SLIDES: The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/7748245591110149.

Xanthotoxol exerts neuroprotective effects via suppression of the inflammatory response in a rat model of focal cerebral ischemia.

We previously found that xanthotoxol, one of the major active ingredients in Cnidium monnieri (L.) Cusson, exerts protective effects in a rat model of focal cerebral ischemia/reperfusion injury by alleviating brain edema, inhibiting the neutrophil infiltration, and decreasing the expression of intercellular adhesion molecule-1 (ICAM-1) and E-selectin. The present study was designed to further determine the possible mechanisms of action of neuroprotective properties of xanthotoxol after cerebral ischemia. Transient focal cerebral ischemia/reperfusion model in male Sprague-Dawley rats was induced by 2-h middle cerebral artery occlusion followed by 24-h reperfusion. Xanthotoxol (5 and 10 mg/kg) or vehicle were administered intraperitoneally at 1 and 12 h after the onset of ischemia. At 24 h after reperfusion, we assessed the effect of xanthotoxol on the blood-brain barrier (BBB) permeability, the production of pro-inflammatory mediators such as interleukin (IL)-1ß, tumor necrosis factor (TNF)-α, IL-8, nitric oxide (NO), inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), and the p65 subunit of the transcription factor, nuclear factor-κB (NF-κB) in the cortex after ischemic insult. The results showed that xanthotoxol treatment significantly attenuated BBB disruption, reduced the IL-1ß, TNF-α, IL-8 and NO level, and attenuated the iNOS activity compared with vehicle-treated animals. Further, xanthotoxol treatment also significantly prevented the ischemia/reperfusion-induced increase in the protein expression of iNOS, COX-2, and the nuclear NF-κB p65. These results, taken together with those of our previous study, suggest that the neuroprotection may be attributed to the ability of xanthotoxol to attenuate the expression of pro-inflammatory mediators and thereby inhibit the inflammatory response after cerebral ischemia.