Search

Tongue cancer, a prevalent form of oral malignancy, particularly manifests as tongue squamous cell carcinoma (TSCC), which holds the highest incidence among oral squamous cell carcinoma cases, representing 43.4 % of occurrences. Presently, surgical resection stands as the primary treatment for TSCC, with no effective pharmaceutical interventions identified. This study aims to search for the potential anti-tumor properties and molecular mechanisms of a rearranged abietane diterpenoid extracted from Clerodendrum mandarinorum. Within this investigation, six known rearranged abietane diterpenoids (1–6) were isolated and characterized from C. mandarinorum. Notably, compound 1 demonstrated the most robust inhibitory effect against CAL-27 cells. Pharmacological assays further substantiated that compound 1 significantly restrained the proliferation, migration, and invasion of CAL-27 cells. Moreover, it was revealed that compound 1 directly interacted with TGFβR2, a pivotal receptor in the downstream signaling pathways of TGF-β/Smad and PI3K/AKT. Transcriptome analysis provided additional confirmation of these observations. Overall, our study highlights the promising potential of compound 1 as a therapeutic agent for the treatment of oral squamous cell carcinoma.

IntroductionDeglycosylated azithromycin (Deg-AZM), a newly developed Class I drug with good therapeutic effects on slow transit constipation, is a small-molecule transgelin agonist that has been approved for clinical trials in 2024. The preclinical pharmacokinetic profile of Deg-AZM was investigated to support further development.MethodsA LC-MS/MS method was established and validated to detected the concentration of Deg-AZM in various biological samples. In vivo tests such as pharmacokinetic studies in rats and dogs, tissue distribution studies in rats, and extraction studies in rats were conducted to investigated the preclinical pharmacokinetic behaviors of Deg-AZM comprehensively. The plasma protein rate of Deg-AZM was determined by rapid equilibrium dialysis method in vitro. The metabolic stability and metabolite profile of Deg-AZM was assessed using pooled mice, rats, dogs, monkeys and humans microsomes in vitro. The PK profiles of Deg-AZM in human was predicted based on physiologically based pharmacokinetic (PBPK) models.ResultsThe plasma protein binding rates of Deg-AZM were lower in mice and rats, higher in dogs, and moderate in humans. The metabolic process of Deg-AZM was similar in rat and human liver microsomes. From Pharmacokinetic studies in rats and dogs, Deg-AZM was rapidly absorbed into the blood and then quickly eliminated. Plasma exposure of Deg-AZM was dose dependent with no accumulation after continuous gavage administration. In addition, there is no significant gender difference in the pharmacokinetic behavior of Deg-AZM. Deg-AZM was widely distributed in the tissues without obvious accumulation, and mainly excreted from the urinary excretion pathway. Furthermore, the pharmacokinetic profiles of Deg-AZM in humans showed dose dependency.ConclusionThe pharmacokinetic profiles of Deg-AZM was fully explored, these results could provide valuable information to support the first-in-human dosage prediction and phase I clinical design.

Fibrotic skin diseases, such as keloids, are pathological results of aberrant tissue healing and are characterized by overgrowth of dermal fibroblasts. Remdesivir (RD), an antiviral drug, has been reported to have pharmacological activities in a wide range of fibrotic diseases. However, whether RD function on skin fibrosis remains unclear. Therefore, in our study, we explored the potential effect and mechanisms of RD on skin fibrosis both in vivo and in vitro. As expected, the results demonstrated that RD alleviated BLM-induced skin fibrosis and attenuates the gross weight of keloid tissues in vivo. Further studies suggested that RD suppressed fibroblast activation and autophagy both in vivo and in vitro. In addition, mechanistic research showed that RD attenuated fibroblasts activation by the TGF-β1/Smad signaling pathway and inhibited fibroblasts autophagy by the PI3K/Akt/mTOR signaling pathway. In summary, our results demonstrate therapeutic potential of RD for skin fibrosis in the future.

Abstract Systemic transplantation of oxygen−glucose deprivation (OGD)-preconditioned primary microglia enhances neurological recovery in rodent stroke models, albeit the underlying mechanisms have not been sufficiently addressed. Herein, we analyzed whether or not extracellular vesicles (EVs) derived from such microglia are the biological mediators of these observations and which signaling pathways are involved in the process. Exposing bEnd.3 endothelial cells (ECs) and primary cortical neurons to OGD, the impact of EVs from OGD-preconditioned microglia on angiogenesis and neuronal apoptosis by the tube formation assay and TUNEL staining was assessed. Under these conditions, EV treatment stimulated both angiogenesis and tube formation in ECs and repressed neuronal cell injury. Characterizing microglia EVs by means of Western blot analysis and other techniques revealed these EVs to be rich in TGF-β1. The latter turned out to be a key compound for the therapeutic potential of microglia EVs, affecting the Smad2/3 pathway in both ECs and neurons. EV infusion in stroke mice confirmed the aforementioned in vitro results, demonstrating an activation of the TGF-β/Smad2/3 signaling pathway within the ischemic brain. Furthermore, enriched TGF-β1 in EVs secreted from OGD-preconditioned microglia stimulated M2 polarization of residing microglia within the ischemic cerebral environment, which may contribute to a regulation of an early inflammatory response in postischemic hemispheres. These observations are not only interesting from the mechanistic point of view but have an immediate therapeutic implication as well, since stroke mice treated with such EVs displayed a better functional recovery in the behavioral test analyses. Hence, the present findings suggest a new way of action of EVs derived from OGD-preconditioned microglia by regulating the TGF-β/Smad2/3 pathway in order to promote tissue regeneration and neurological recovery in stroke mice.

Inhibition of fatty acid synthesis (FAS) stimulates tumor cell death and reduces angiogenesis. When SH-SY5Y cells or primary neurons are exposed to hypoxia only, inhibition of FAS yields significantly enhanced cell injury. The pathophysiology of stroke, however, is not only restricted to hypoxia but also includes reoxygenation injury. Hence, an oxygen-glucose-deprivation (OGD) model with subsequent reoxygenation in both SH-SY5Y cells and primary neurons as well as a murine stroke model were used herein in order to study the role of FAS inhibition and its underlying mechanisms. SH-SY5Y cells and cortical neurons exposed to 10 h of OGD and 24 h of reoxygenation displayed prominent cell death when treated with the Acetyl-CoA carboxylase inhibitor TOFA or the fatty acid synthase inhibitor cerulenin. Such FAS inhibition reduced the reduction potential of these cells, as indicated by increased NADH2+/NAD+ ratios under both in vitro and in vivo stroke conditions. As observed in the OGD model, FAS inhibition also resulted in increased cell death in the stroke model. Stroke mice treated with cerulenin did not only display increased brain injury but also showed reduced neurological recovery during the observation period of 4 weeks. Interestingly, cerulenin treatment enhanced endothelial cell leakage, reduced transcellular electrical resistance (TER) of the endothelium and contributed to poststroke blood-brain barrier (BBB) breakdown. The latter was a consequence of the activated NF-κB pathway, stimulating MMP-9 and ABCB1 transporter activity on the luminal side of the endothelium. In conclusion, FAS inhibition aggravated poststroke brain injury as consequence of BBB breakdown and NF-κB-dependent inflammation.

Space-time steering vector mismatch of targets usually happens in the space-time adaptive processing (STAP) technique, causing space-time beam distortion. Due to the effects of clutter spectrum broadening and jamming, performance of the conventional STAP method deteriorates dramatically. This paper proposes a novel robust STAP method to improve the performance of clutter suppression and moving target detection. The proposed method employs the alternating projection and clutter cancellation method, to reconstruct the clutter plus jamming plus noise covariance matrix (CJNCM) and re-estimate the target steering vector. Firstly, reconstruction of CJNCM consists of summing the eigenvectors of the projection operator, combining the sample covariance matrix and the integral covariance matrix (ICM) of specific region. Secondly, the re-estimated target steering vector is obtained by estimating the dominant eigenvector of the ICM of the Region of Interest (ROI), which contains the target signal purely because CJNCM is cancelled before estimation. Finally, the robust space-time adaptive filtering weight vector is calculated through the MVDR method with the reconstructed CJNCM and the re-estimated target steering vector. Simulation results indicate that the proposed algorithm shows robust performance against space-time steering vector mismatch, better output signal-to-noise ratio performance and better moving target detection performance than the traditional robust STAP method.

In this paper, we present a subspace projection and covariance matrix reconstruction (SPCMR) algorithm for adaptive beamforming to improve the robustness against large SV mismatch. The SPCMR algorithm consists of two parts: projection subspaces estimation and interference-plus-noise covariance matrix (INCM) reconstruction. Specifically, we estimate two projection subspaces containing the signal component and obtain the signal SV from their intersection. The first projection subspace is estimated from the constructed signal covariance matrix via the distortionless responses principle. The second one is gotten according to the subspace proximity between the nominal signal SV and the eigenvectors of the sample covariance matrix. Subsequently, the interference SVs are estimated by using the Capon spatial estimator, and each interference power is obtained via the oblique projectors. After that, an accurate INCM is reconstructed, and the SPCMR beamformer is proposed. The simulation results show that the SPCMR algorithm is robust to several model mismatches and outperforms other adaptive algorithms.

A novel redox-responsive PEG-sheddable copolymer of disulfide-linked polyethylene glycol 5000-lysine-di-tocopherol succinate (P5kSSLV) was designed and synthesized. Thin-film hydration method was used to prepare DOX-loaded P5kSSLV nanomicelle. To optimize the preparation technology, we investigate the effects of dosage, type of organic solvent, hydration temperature and time, and cryoprotectant on drug-loading content, encapsulation efficiency, particle size, and zeta potential. The mean particle size and zeta potential were determined by Zetasizer. The morphology of the P5kSSLV-DOX nanomicelles was visualized by transmission electron microscopy. The drug-loading content and encapsulation efficiency of P5kSSLV-DOX nanomicelle were investigated by UV. The drug-loading content, encapsulation efficiency, particle size, and zeta potential of the final optimized nanomicelles were 4.58%, 97.20%, 30.21 nm and −0.84 mV, respectively. In addition, the stability of nanomicelles was investigated, which included dilution stability and storage stability. The results showed that P5kSSLV-DOX nanomicelle had good dilution stability and storage stability at 4 °C. The preparation method of P5kSSLV-DOX nanomicelle with thin-film hydration method was practical and simple, which was valuable to be further studied.