Berberine alleviates pulmonary hypertension through Trx1 and ß-catenin signaling pathways in pulmonary artery smooth muscle cells.

Pulmonary arterial hypertension (PAH) is closely associated with profound vascular remodeling, especially pulmonary arterial medial hypertrophy and muscularization, due to aberrant proliferation of pulmonary artery smooth muscle cells (PASMCs). Berberine, a drug commonly used to treat inflammation, may be a novel therapeutic option for PAH by improving pulmonary artery remodeling. The present study investigated whether berberine affected Trx1/ß-catenin expression and/or activity and whether it could reduce the development of pulmonary hypertension in an experimental rat model and proliferation in human PASMCs (HPASMCs). The results showed that increased proliferation in hypoxia-induced healthy PASMCs or PAH PASMCs was associated with a significant increase in Trx1 and ß-catenin expression. Treatment with the Trx1-specific inhibitor PX-12 significantly reduced pulmonary arterial pressure and vascular remodeling, as well as improved in vivo cardiac function and right ventricular hypertrophy, in Su/Hox-induced PAH rats. Berberine reversed right ventricular systolic pressure and right ventricular hypertrophy and decreased pulmonary vascular remodeling in the rats. Furthermore, berberine had an antiproliferative effect on hypoxia-induced HPASMC proliferation in a manner likely mediated by inhibiting Trx1 and its target gene ß-catenin expression. Our work will help elucidate novel strategies for PAH treatment involving the traditional Chinese medicine berberine, and Trx1/ß-catenin may be a promising therapeutic target.

TDDFT study on the simultaneous sensing mechanism for peroxynitrite and glutathione by a bifunctional fluorescent probe.

Using time-dependent density functional theory (TDDFT) method, the response mechanism of a reported bifunctional fluorescent probe for simultaneous recognition of peroxynitrite and glutathione (Chem. Commun. 2018, 54, 11336) was theoretically studied. Calculated vertical excitation energies based on the ground-state and excited-state geometries were consistent with the corresponding experimental ultraviolet-visible and fluorescence spectra. In the ground state, electron delocalization in the probe was limited because its geometry was restrained by steric hindrance. Frontier molecular orbital analysis has shown that the probe should undergo photoinduced electron transfer (PET) from the benzothiazole moiety to the maleimide moiety after excitation. The nonplanar structure together with PET led to fluorescence quenching of the probe. The probe could be dealkylated by peroxynitrite anion. The resulting intramolecular hydrogen bond increasesd the planarity of the molecule, while also gave rise to an excited-state proton-transfer process. Moreover, the addition reaction between the probe and glutathione inhibited the PET process. These two analytes together contributed to the fluorescence enhancement of the final product. This theoretical sensing mechanism for peroxynitrite and glutathione may potentially be important for the design and enhancement of novel probes.

Apolipoprotein A1 is associated with pulmonary vascular resistance and adverse clinical outcomes in patients with pulmonary hypertension secondary to heart failure.

Pulmonary hypertension secondary to heart failure (HF-PH) combined with pulmonary vascular remodeling has a high mortality rate. Apolipoprotein A1 (ApoA1) has been shown to adversely affect outcomes in patients with HF. A prospective follow-up study was performed on 239 consecutive patients with HF-PH who underwent right heart catheterization. Proteomics technology was used to analyze different proteins in plasma between post- and precapillary pulmonary hypertension (CpcPH) and isolated postcapillary pulmonary hypertension (IpcPH) filtered by propensity score matching. Ultimately, 175 patients were enrolled and followed for an average of 4.4 years. Lipoprotein components in plasma were measured, and the following clinical events were tracked. Proteomics data showed that lipid metabolism and inflammation were different between CpcPH and IpcPH. ApoA1 levels in HF-PH patients with CpcPH were lower than those in HF-PH patients with IpcPH. The patients with lower ApoA1 levels (≤1.025 g/L) were in a higher New York Heart Association class and had high levels of NT-proBNP, mean pulmonary artery pressure, PVR, and diastolic pressure gradient. Besides, HF-PH patients with lower ApoA1 levels had a 2.836-fold higher relative risk of comorbid CpcPH compared with patients with higher ApoA1 levels. Moreover, patients with lower ApoA1 levels had a lower survival rate after adjusting for CpcPH. In conclusion, ApoA1 levels were negatively correlated with PVR levels. Lower ApoA1 levels were an independent risk factor for pulmonary vascular remodeling in HF-PH patients. The survival of HF-PH patients with lower ApoA1 levels was reduced.

Doxorubicin-Conjugated Innovative 16-mer DNA Aptamer-Based Annexin A1 Targeted Anti-Cancer Drug Delivery.

Aptamers are small, functional single-stranded DNA or RNA oligonucleotides that bind to their targets with high affinity and specificity. Experimentally, aptamers are selected by the systematic evolution of ligands by exponential enrichment (SELEX) method. Here, we have used rational drug designing and bioinformatics methods to design the aptamers, which involves three different steps. First, finding a probable aptamer-binding site, and second, designing the recognition and structural parts of the aptamers by generating a virtual library of sequences, selection of specific sequence via molecular docking, molecular dynamics (MD) simulation, binding energy calculations, and finally evaluating the experimental affinity. Following this strategy, a 16-mer DNA aptamer was designed for Annexin A1 (ANXA1). In a direct binding assay, DNA1 aptamer bound to the ANXA1 with dissociation constants value of 83 nM. Flow cytometry and fluorescence microscopy results also showed that DNA1 aptamer binds specifically to A549, HepG2, U-87 MG cancer cells that overexpress ANXA1 protein, but not to MCF7 and L-02, which are ANXA1 negative cells. We further developed a novel system by conjugating DNA1 aptamer with doxorubicin and its efficacy was studied by cellular uptake and cell viability assay. Also, anti-tumor analysis showed that conjugation of doxorubicin with aptamer significantly enhances targeted therapy against tumors while minimizing overall adverse effects on mice health.

Biomechanical effects of C2-C7 intersegmental stability due to laminectomy with unilateral and bilateral facetectomy.

STUDY DESIGN: The biomechanical responses resulting from laminectomy with graded unilateral and bilateral facetectomy were quantified using a three-dimensional nonlinear finite element model of the C2-C7 motion segments. OBJECTIVE: To study the influence of laminectomy with graded unilateral and bilateral facetectomy on the cervical spinal biomechanics. SUMMARY OF BACKGROUND DATA: Cervical spinal stenosis is a condition that is caused by the narrowing of the spinal canal. Laminectomy and facetectomy are commonly used surgical procedures for decompressing cervical spinal stenosis. Resection of the posterior structures causes instability and affects the internal stresses of the cervical spinal components. However, the influence of these surgical procedures on the biomechanical responses of the cervical spine has not been studied. METHODS: A nonlinear finite element model of the intact C2-C7 was constructed and validated. Ten surgically altered models were created from the intact model and were tested under physiologic loading. Because of the inclusion of five motion segments, it was possible to determine the intersegmental responses and internal cortical shell and disc stresses in the adjacent altered and unaltered spinal components. RESULTS: Under combined flexion and extension, intersegmental motions at C4-C5 and C5-C6 increased significantly after C5 laminectomy. Subsequent facetectomy performed at C5 and C6 on the laminectomized model only affected the responses at the C5-C6 segment. Overall, slight intersegmental responses of up to 5% were observed at the adjacent levels of C3-C4 and C6-C7. Laminectomy did not cause any significant increase in the intersegmental motions under lateral bending and axial rotation. Extending the surgical procedures to unilateral and bilateral facetectomy only increased the intersegmental motions slightly. Similar increases in the intervertebral disc and the cortical shell stresses were observed. These findings may partially explain the clinical observations of enhanced osteophytes formation. CONCLUSIONS: This study provides a better understanding of the surgically altered cervical spinal biomechanics and may help formulate treatment strategies such as spinal implants.