Scale-Up Preparation of Manganese-Iron Prussian Blue Nanozymes as Potent Oral Nanomedicines for Acute Ulcerative Colitis.

Prussian blue (PB) nanozymes are demonstrated as effective therapeutics for ulcerative colitis (UC), yet an unmet practical challenge remains in the scalable production of these nanozymes and uncertainty over their efficacy. With a novel approach, a series of porous manganese-iron PB (MnPB) colloids, which are shown to be efficient scavengers for reactive oxygen species (ROS) including hydroxyl radical, superoxide anion, and hydrogen peroxide, are prepared. In vitro cellular experiments confirm the capability of the nanozyme to protect cells from ROS attack. In vivo, the administration of MnPB nanozyme through gavage at a dosage of 10 mg kg-1 per day for three doses in total potently ameliorates the pathological symptoms of acute UC in a murine model, resulting in mitigated inflammatory responses and improved viability rate. Significantly, the nanozyme produced at a large scale can be achieved at an unprecedented yield weighting ≈11 g per batch of reaction, demonstrating comparable anti-ROS activities and treatment efficacy to its small-scale counterpart. This work represents the first demonstration of the scale-up preparation of PB analog nanozymes for UC without compromising treatment efficacy, laying the foundation for further testing of these nanozymes on larger animals and promising clinical translation.

Cav3.2 channel regulates cerebral ischemia/reperfusion injury: a promising target for intervention.

JOURNAL/nrgr/04.03/01300535-202419110-00028/figure1/v/2024-03-08T184507Z/r/image-tiff Calcium influx into neurons triggers neuronal death during cerebral ischemia/reperfusion injury. Various calcium channels are involved in cerebral ischemia/reperfusion injury. Cav3.2 channel is a main subtype of T-type calcium channels. T-type calcium channel blockers, such as pimozide and mibefradil, have been shown to prevent cerebral ischemia/reperfusion injury-induced brain injury. However, the role of Cav3.2 channels in cerebral ischemia/reperfusion injury remains unclear. Here, in vitro and in vivo models of cerebral ischemia/reperfusion injury were established using middle cerebral artery occlusion in mice and high glucose hypoxia/reoxygenation exposure in primary hippocampal neurons. The results showed that Cav3.2 expression was significantly upregulated in injured hippocampal tissue and primary hippocampal neurons. We further established a Cav3.2 gene-knockout mouse model of cerebral ischemia/reperfusion injury. Cav3.2 knockout markedly reduced infarct volume and brain water content, and alleviated neurological dysfunction after cerebral ischemia/reperfusion injury. Additionally, Cav3.2 knockout attenuated cerebral ischemia/reperfusion injury-induced oxidative stress, inflammatory response, and neuronal apoptosis. In the hippocampus of Cav3.2-knockout mice, calcineurin overexpression offset the beneficial effect of Cav3.2 knockout after cerebral ischemia/reperfusion injury. These findings suggest that the neuroprotective function of Cav3.2 knockout is mediated by calcineurin/nuclear factor of activated T cells 3 signaling. Findings from this study suggest that Cav3.2 could be a promising target for treatment of cerebral ischemia/reperfusion injury.

Peroxiredoxin-5 Knockdown Accelerates Pressure Overload-Induced Cardiac Hypertrophy in Mice.

A recent study showed that peroxiredoxins (Prxs) play an important role in the development of pathological cardiac hypertrophy. However, the involvement of Prx5 in cardiac hypertrophy remains unclear. Therefore, this study is aimed at investigating the role and mechanisms of Prx5 in pathological cardiac hypertrophy and dysfunction. Transverse aortic constriction (TAC) surgery was performed to establish a pressure overload-induced cardiac hypertrophy model. In this study, we found that Prx5 expression was upregulated in hypertrophic hearts and cardiomyocytes. In addition, Prx5 knockdown accelerated pressure overload-induced cardiac hypertrophy and dysfunction in mice by activating oxidative stress and cardiomyocyte apoptosis. Importantly, heart deterioration caused by Prx5 knockdown was related to mitogen-activated protein kinase (MAPK) pathway activation. These findings suggest that Prx5 could be a novel target for treating cardiac hypertrophy and heart failure.

Silencing IL12p35 Promotes Angiotensin II-Mediated Abdominal Aortic Aneurysm through Activating the STAT4 Pathway.

Background and Purpose. Abdominal aortic aneurysm (AAA) is a chronic inflammatory disorder and the important causes of death among men over the age of 65 years. Interleukin-12p35 (IL12p35) is an inflammatory cytokine that participates in a variety of inflammatory diseases. However, the role of IL12p35 in the formation and development of AAA is still unknown. Experimental Approach. Male apolipoprotein E-deficient (Apoe-/-) mice were generated and infused with 1.44 mg/kg angiotensin II (Ang II) per day. We found that IL12p35 expression was noticeably increased in the murine AAA aorta and isolated aortic smooth muscle cells (SMCs) after Ang II stimulation. IL12p35 silencing promoted Ang II-induced AAA formation and rupture in Apoe-/- mice. IL12p35 silencing markedly increased the expression of inflammatory cytokines, including IL-1ß, IL-6, and tumor necrosis factor-α (TNF-α), in both the serum and AAA aorta. Additionally, IL12p35 silencing exacerbated SMC apoptosis in Apoe-/- mice after Ang II infusion. IL12p35 silencing significantly increased signal transducer and activator of transcription (STAT) 4 phosphorylation levels in AAA mice, and STAT4 knockdown abolished the IL12p35-mediated proinflammatory response and SMC apoptosis. Interpretation. Silencing IL12p35 promotes AAA formation by activating the STAT4 pathway, and IL12p35 may serve as a novel and promising therapeutic target for AAA treatment.

Interleukin-22 Plays a Protective Role by Regulating the JAK2-STAT3 Pathway to Improve Inflammation, Oxidative Stress, and Neuronal Apoptosis following Cerebral Ischemia-Reperfusion Injury.

The interleukins (ILs) are a pluripotent cytokine family that have been reported to regulate ischemic stroke and cerebral ischemia/reperfusion (I/R) injury. IL-22 is a member of the IL-10 superfamily and plays important roles in tissue injury and repair. However, the effects of IL-22 on ischemic stroke and cerebral I/R injury remain unclear. In the current study, we provided direct evidence that IL-22 treatment decreased infarct size, neurological deficits, and brain water content in mice subjected to cerebral I/R injury. IL-22 treatment remarkably reduced the expression of inflammatory cytokines, including IL-1ß, monocyte chemotactic protein- (MCP-) 1, and tumor necrosis factor- (TNF-) α, both in serum and the ischemic cerebral cortex. In addition, IL-22 treatment also decreased oxidative stress and neuronal apoptosis in mice after cerebral I/R injury. Moreover, IL-22 treatment significantly increased Janus tyrosine kinase (JAK) 2 and signal transducer and activator of transcription (STAT) 3 phosphorylation levels in mice and PC12 cells, and STAT3 knockdown abolished the IL-22-mediated neuroprotective function. These findings suggest that IL-22 might be exploited as a potential therapeutic agent for ischemic stroke and cerebral I/R injury.

Palmatine Protects against Cerebral Ischemia/Reperfusion Injury by Activation of the AMPK/Nrf2 Pathway.

Palmatine (PAL), a natural isoquinoline alkaloid, possesses extensive biological and pharmaceutical activities, including antioxidative stress, anti-inflammatory, antitumor, neuroprotective, and gastroprotective activities. However, it is unknown whether PAL has a protective effect against ischemic stroke and cerebral ischemia/reperfusion (I/R) injury. In the present study, a transient middle cerebral artery occlusion (MCAO) mouse model was used to mimic ischemic stroke and cerebral I/R injury in mice. Our study demonstrated that PAL treatment ameliorated cerebral I/R injury by decreasing infarct volume, neurological scores, and brain water content. PAL administration attenuated oxidative stress, the inflammatory response, and neuronal apoptosis in mice after cerebral I/R injury. In addition, PAL treatment also decreases hypoxia and reperfusion- (H/R-) induced neuronal injury by reducing oxidative stress, the inflammatory response, and neuronal apoptosis. Moreover, the neuroprotective effects of PAL were associated with the activation of the AMP-activated protein kinase (AMPK)/nuclear factor E2-related factor 2 (Nrf2) pathway, and Nrf2 knockdown offsets PAL-mediated antioxidative stress and anti-inflammatory effects. Therefore, our results suggest that PAL may be a novel treatment strategy for ischemic stroke and cerebral I/R injury.

Analgesic Effects of Different κ-Receptor Agonists Used in Daytime Laparoscopic Cholecystectomy.

BACKGROUND: Comparing the effect of two different κ-receptor agonists, nalbuphine and oxycodone, and regular morphine in patients for prophylactic analgesia of acute pain after daytime laparoscopic cholecystectomy. METHODS: One hundred and twenty-four patients undergoing laparoscopic cholecystectomy were randomly allocated to receive nalbuphine (group N), oxycodone (group O), and morphine (group M). The three groups were all given intravenous injection (iv.) of 0.15 mg/kg injection before incision and 0.05 mg/kg injection at the end of pneumoperitoneum. The Visual Analogue Scale (VAS) scores (incision, visceral, and shoulder) and Ramsay sedation scores at 1, 2, 4, 8, 12, 16, 20, and 24 hours after surgery, the time of extubation, the incidence of postoperative adverse events, the satisfaction of pain treatment, and the duration of stay after surgery were all recorded. RESULTS: Compared with group M, the VAS scores of visceral pain at rest decreased in group N and group O at 1-8 h after surgery (P < 0.05). The VAS scores of visceral pain at movement in group N decreased longer than those in group O (P < 0.05). Compared with that of group M, the postoperative time in Ramsay sedation score of group O increased longer than that of group N (P < 0.05). Compared with group N, patients had worse sleep quality in group O, longer length of stay in group M, and lower satisfaction in both groups. CONCLUSION: Compared with morphine, prophylactic use of the κ-receptor agonists, nalbuphine and oxycodone, during laparoscopic cholecystectomy can reduce postoperative visceral pain. Furthermore, the nalbuphine group had fewer adverse reactions, better analgesia, and better satisfaction.

In vitro and ex vivo angiogenic effects of roxarsone on rat endothelial cells.

Roxarsone, a feed additive, is being used worldwide to promote animal growth. However, the potential effect of roxarsone on angiogenesis has not been extensively characterized. We examined the ability of roxarsone to promote angiogenesis of rat endothelial cells in vitro and from rat aorta rings ex vivo. Endothelial cells from rats were exposed to 0.01-10.00µM roxarsone, 5ng/mL vascular endothelial growth factor (VEGF) as a positive control or phosphate buffer saline (PBS) as a negative control. Cell proliferation was measured by MTT assay, and the content of VEGF in supernatants was measured by enzyme-linked immunosorbent assay and Western blotting. A Matrigel-induced tube formation assay was used to evaluate the effects of roxarsone on endothelial cells. Additionally, the total number and length of microvessels sprouted from rat aortic rings were measured for ex vivo investigation of angiogenesis. Results showed that the cell viability and total number and length of capillary-like tube formations after roxarsone treatment was significantly higher than that of negative (P<0.05), with a maximum effect at 1.00µM exposure. Furthermore, the number of microvessels sprouted from aortic rings treated for 4h with 0.1-10.0µM roxarsone was significantly higher than that of PBS treatment, with a peak value of 1.0µM. These results further demonstrate the potential of roxarsone to promote angiogenesis in vitro and ex vivo.

Determination and depletion of dehydroacetic acid residue in chicken tissues.

A high-performance liquid chromatography (HPLC) method was developed to determine dehydroacetic acid (DHA) residues in chicken muscle, liver and kidney. DHA was extracted using acetonitrile, and clean-up performed using a strong anion exchange (PAX) SPE column. The cleaned-up samples were separated by HPLC with a C18 column and determined at 290 nm. Extraction recoveries of DHA from samples fortified at 0.5-5 mg/kg levels ranged from 88.2% to 93.9% in muscle, 83.8% to 86.6% in liver and 83.8% to 89.8% in kidney, with coefficients of variation <6.44%. The limit of detection was 0.05 mg/kg and limit of quantification was 0.2 mg/kg. DHA was not detectable in muscle at 13-15 days after final administration of DHA, at 11 days in kidney and 17 days in liver. The method described herein is suitable for routine quantitative analyses of DHA in animal tissues and can be easily applied to the analysis of other matrices such as milk, serum and tissue samples from other animals.