Psoralidin protects against cerebral hypoxia/reoxygenation injury: Role of GAS6/Axl signaling

Qianggu concentrate: unlocking bone protection power via antioxidative SIRT1/NRF2/HO-1 pathways in type 2 diabetic osteoporosis

Background

Qianggu Concentrate (QGHJ), a traditional Chinese medicine, is extensively used to treat Type 2 Diabetic Osteoporosis (T2DOP). Despite its widespread use, research on its therapeutic mechanisms within T2DOP is notably scarce.

Objective

To explore QGHJ's osteoprotection in T2DOP rats and BMSCs, focusing on the antioxidant activation of SIRT1/NRF2/HO-1 and NRF2 nuclear migration.

Methods

QGHJ constituent analysis was performed using UPLC-HRMS. Safety, bone-health efficacy, and glucose metabolic effects in T2DOP rats were evaluated via general condition assessments, biomarker profiling, micro-CT, biomechanics, staining methods, and ELISA, supplemented by RT-qPCR and Western blot. BMSCs' responses to QGHJ under oxidative stress, including viability, apoptosis, and osteogenic differentiation, were determined using CCK-8, flow cytometry, ALP/ARS staining, and molecular techniques. The modulation of the SIRT1/NRF2/HO-1 pathway by QGHJ was explored through oxidative stress biomarkers, immunofluorescence, and Western blot assays.

Results

UPLC-HRMS identified flavonoids, monoterpenes, and isoflavones as QGHJ's key compounds. In vivo, QGHJ proved safe and effective for T2DOP rats, enhancing bone mineral density, microenvironment, and biomechanical properties without impairing vital organs. It modulated bone markers PINP, TRACP 5b, RUNX2 and PPARγ, favoring bone anabolism and reduced catabolism, thus optimizing bone integrity. QGHJ also regulated glycemia and mitigated insulin resistance. In vitro, it preserved BMSCs' viability amidst oxidative stress, curbed apoptosis, and fostered osteogenesis with regulated RUNX2/PPARγ expression. Mechanistic insights revealed QGHJ activated the SIRT1/NRF2/HO-1 pathway, augmented NRF2 nuclear translocation, and enhanced the antioxidative response, promoting bone health under stress.

Conclusion

In T2DOP rat and BMSCs oxidative stress models, QGHJ's bone protection is anchored in its antioxidative mechanisms via the SIRT1/NRF2/HO-1 pathway activation and NRF2 nuclear translocation.

Discovery of a 1,6-naphthyridin-4-one-based AXL inhibitor with improved pharmacokinetics and enhanced in vivo antitumor efficacy

The receptor tyrosine kinase AXL has emerged as an attractive target in anticancer drug discovery. Herein, we described the discovery of a new series of 1,6-naphthyridin-4-one derivatives as potent AXL inhibitors. Starting from a low in vivo potency compound 9 which was previously reported by our group, we utilized structure-based drug design and scaffold hopping strategies to discover potent AXL inhibitors. The privileged compound 13c was a highly potent and orally bioavailable AXL inhibitor with an IC50 value of 3.2 ± 0.3 nM. Compound 13c exhibited significantly improved in vivo antitumor efficacy in AXL-driven tumor xenograft mice, causing tumor regression at well-tolerated dose, and demonstrated favorable pharmacokinetic properties (MRT = 16.5 h, AUC0-∞ = 59,815 ng h/mL) in Sprague-Dawley rats. These results suggest that 13c is a promising therapeutic candidate for AXL-targeting cancer treatment.

Activation of ITLN-1 attenuates oxidative stress injury via activating SIRT1/PGC1-α signaling in neuroblastoma cells

Cerebral injury is closely associated with enhanced oxidative stress. A newly discovered secretory adipocytokine, intelectin-1 (ITLN-1), has been shown to have beneficial effects in neuroprotection in epidemiological studies. However, the specific molecular mechanism of ITLN-1 in protecting against cerebral oxidative stress needs further investigation. In this study, we hypothesize that ITLN-1 plays a protective role against oxidative stress injury through the SIRT1/PGC1-α signaling pathway in neuromatocytes. We used hydrogen peroxide (H2 O2 ) as a oxidative stress model to simulate oxidative stress injury. Then, small interfering RNAs (siRNAs) was used to knock down SIRT1 in N2a cells with or without ITLN overexpression, followed by H2 O2 -induced injury. We observed that H2 O2 injury significantly decreased the levels of ITLN-1, SIRT1, and PGC-1α. However, ITLN overexpression reversed H2 O2 -induced decline in cell viability and rise in apoptosis and intracellular ROS levels in N2a cells, while ITLN siRNA worsened the neurocyte injury. Furthermore, SIRT1 knockdown reversed the positive effect of ITLN overexpression on oxidative stress injury in N2a cells. Taken together, these findings suggest that ITLN-1 exerts neuroprotective effects against oxidative stress injury primarily through the SIRT1/PGC-1α axis.

Identification of PIK3R5 as a hub in septic myocardial injury and the cardioprotective effects of Psoralidin

BACKGROUND

Myocardial injury is a severe complication of sepsis, resulting in substantial morbidity and mortality. Psoralidin (PSO), derived from the seeds of Psoralea corylifolia L., has garnered considerable attention due to its potent pharmacological effects, including anti-inflammatory and antibacterial effects.

PURPOSE

Our previous work conducted affirmed that PSO has a protective effect on sepsis and septic myocardial injury, however the specific molecular mechanisms need further clarification.

STUDY DESIGN

This objective of this study was to use three analytic modalities and bioinformatics methods to identify potential targets, followed by experimental verification.

METHODS

A series of experiments methods (including echocardiography, HE, western blot, qPCR, RNA-seq, network pharmacology) were used to evaluate the effects of PSO against sepsis and septic myocardial injury in cecal ligation and puncture (CLP)-injured BALB/c mice and lipopolysaccharide (LPS)-injured HL-1 cardiomyocytes.

RESULTS

Firstly, a group of sepsis-related genes were identified by integrating database surveys, RNA-seq analysis, and weighted gene co-expression network analysis (WCGNA). Subsequently, the pharmacological targets of PSO were predicted. Furthermore, the identification of phosphoinositide 3- kinase regulatory subunit 5 (PIK3R5) as a crucial hub gene was accomplished via protein-protein interaction network and molecular docking approach. In vivo experiments showed that PSO treatment alleviated septic myocardial injury, as evidenced by improved cardiac function indicators and inflammation response. Similar results were obtained in vitro experiments. Importantly, the expression of PI3KR5 was decreased in the myocardium and cardiomyocytes, and the effect was reversed by PSO treatment.

CONCLUSION

This study systematically revealed the key targets of PSO in the treatment of septic myocardial injury. These findings offer valuable insights into disease-drug targets, which have certain clinical significance to exploring disease biomarkers and potential therapeutic targets for septic patients.

GAS6 attenuates sepsis-induced cardiac dysfunction through NLRP3 inflammasome-dependent mechanism

Sepsis is a major health threat and often results in heart failure. Growth arrest-specific gene 6 (GAS6), a 75-kDa vitamin K-dependent protein, participates in immune regulation and inflammation through binding to AXL (the TAM receptor family). This study was designed to examine the myocardial regulatory role of GAS6 in sepsis. Serum GAS6 levels were increased in septic patients and mice while myocardial GAS6 levels were decreased in septic mice. Single-cell RNA sequencing further revealed a decline in GAS6 levels of nearly all cell clusters including cardiomyocytes. GAS6 overexpression via adeno-associated virus 9 (AAV9) overtly improved cardiac dysfunction in cecum ligation and puncture (CLP)-challenged mice, along with alleviated mitochondrial injury, endoplasmic reticulum stress, oxidative stress, and apoptosis. However, GAS6-elicited beneficial effects were removed by GAS6 knockout. The in vitro study was similar to these findings. Our data also noted a downstream effector role for NLRP3 in GAS6-initiated myocardial response. GAS6 knockout led to elevated levels of NLRP3, the effect of which was reconciled by GAS6 overexpression. Taken together, these results revealed the therapeutical potential of targeting GAS6/AXL-NLRP3 signaling in the management of heart anomalies in sepsis.

Silibinin exerts neuroprotective effects against cerebral hypoxia/reoxygenation injury by activating the GAS6/Axl pathway

Ischemic stroke is regarded one of the most common causes of brain vulnerability. Silibinin (SIL), extracted from the seeds of Silybinisus laborinum L., has been found to exhibit obvious therapeutic effects on neurodegenerative diseases. GAS6 has been proven to have significant neuroprotective effects; however, the role of SIL and GAS6 in ischemic stroke remains unclear. This study aimed to investigate the protective effects of SIL against cerebral ischemia-reperfusion injury in neuroblastoma N2a cells, as well as the mechanisms involved. Firstly, the toxicity of SIL was evaluated, and safe concentrations were chosen for subsequent experiments. Then, SIL exerts significant neuroprotection against hypoxia/reoxygenation (HR) injury in N2a cells, as manifested by increased cell viability, decreased apoptotic rate, LDH, and ROS generation. Additionally, SIL was found to inhibit HR-induced apoptosis, mitochondria dysfunction, and oxidative stress. However, silencing of GAS6 inhibited the neuroprotective effects of SIL. To sum up, these results suggest that SIL may be a promising therapeutic agent for the treatment of ischemic stroke.

Activation of NR1H3 signaling pathways by psoralidin attenuates septic myocardial injury

Sepsis can cause various organ dysfunction, which heart failure may be associated with significant mortality. Psoralidin (PSO), one of the main bioactive compounds from the seeds of Psoralea corylifolia L, exhibits remarkable protective effects in diseases, including cancer, osteoporosis, and depression. Recently, NR1H3 is one of the emerging nuclear receptors targets for the various drugs. This study first reported the role of PSO in septic myocardial injury, which was mainly attributed to the NR1H3-dependent manner. NR1H3 knockout mice subjected to cecal ligation and puncture (CLP) were used to investigate the involvement of NR1H3 in PSO protection evaluate. Our results showed that PSO prominently improved cardiac function, blood routine and blood biochemistry, attenuated inflammation, inhibited oxidative stress, improved mitochondrial function, regulated ERS, suppressed apoptosis, and increased NR1H3 and p-AMPK levels. However, NR1H3 knockout reversed the positive role of PSO in septic mice. Furthermore, activation of NR1H3 by T0901317 also increased the activity of AMPK and ACC in the HL-1 cardiomyocytes, indicating the regulatory relationship between NR1H3 and AMPK signaling. This study first demonstrated the beneficial effect of PSO in septic myocardial injury through activation of NR1H3/AMPK pathway.

Inhibition of ferroptosis by icariin treatment attenuates excessive ethanol consumption-induced atrial remodeling and susceptibility to atrial fibrillation, role of SIRT1

Ferroptosis contributes to the pathogenesis of atrial fibrillation (AF), although the mechanisms are still largely uncovered. The current study was designed to explore the pharmacological effects of icariin against ethanol-induced atrial remodeling, if any, and the mechanisms involved with a focus on SIRT1 signaling. Excessive ethanol-treated animals were administered with Ferrostatin-1, Erastin or icariin to evaluate the potential effects of icariin or ferroptosis. Then, the underling mechanisms was further explored in the in vitro experiments using HL-1 atrial myocytes. Excessive ethanol administration caused significant atrial damage as evidenced by increased susceptibility to AF, altered atrial conduction pattern, atrial enlargement, and enhanced fibrotic markers. These detrimental effects were reversed by Ferrostatin-1 or icariin treatment, while Erastin co-administration markedly abolished the beneficial actions conferred by icariin. Mechanistically, ethanol-treated atria exhibited markedly up-regulated pro-ferroptotic protein (PTGS2, ACSL4, P53) and suppressed anti-ferroptotic molecules (GPX4, FTH1). Icariin treatment inhibited ethanol-induced atrial ferroptosis by reducing atrial mitochondrial damage, ROS accumulation and iron overload. Interestingly, the in vivo and in vitro data showed that icariin activated atrial SIRT1-Nrf-2-HO-1 signaling pathway, while EX527 not only reversed these effects, but also abolished the therapeutic effects of icariin. Moreover, the stimulatory effects on GPX4, SLC7A11 and the suppressive effects on ACSL4, P53 conferred by icariin were blunted by EX527 treatment. These data demonstrate that ferroptosis plays a causative role in the pathogenesis of ethanol-induced atrial remodeling and susceptibility to AF. Icariin protects against atrial damage by inhibiting ferroptosis via SIRT1 signaling. Its role as a prophylactic/therapeutic drug deserves further clinical study.