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Background: Targeted protein degradation relies on inducing proximity between an E3 ubiquitin ligase and a target protein, and subsequent proteasomal degradation of the latter. Biophysical methods allow the measurement of the ternary complex formation by recombinant target and E3 ligase proteins in the presence of molecular glues and bifunctional degraders. The development of new chemotypes of degraders mediating ternary complex formation of unknown dimensions and geometries requires the use of different biophysical approaches., Methods: The TR-FRET and AlphaLISA platforms have been applied to study molecular glues and bifunctional degraders. The performance of the label-based proximity assays was compared with the BLI method, which is a label-free, sensor-based approach., Results: We present and compare two commonly used assays to monitor proximity induction, AlphaLISA and TR-FRET. The LinkScape system consisting of the CaptorBait peptide and the CaptorPrey protein is a novel method of protein labeling compatible with TR-FRET assay., Conclusions: The TR-FRET and AlphaLISA proximity assays enable detection of ternary complexes formed between an E3 Ligase, a target protein and a small molecule degrader. Experiments with different chemotypes of GSPT1 degraders showed that ALphaLISA was more susceptible to chemotype-dependent interference than TR-FRET assay., General Significance: The discovery and optimization of small-molecule inducers of ternary complexes is greatly accelerated by using biophysical assays. The LinkScape-based TR-FRET assay is an alternative to antibody-based proximity assays due to the CaptorPrey's subnanomolar affinity to the CaptorBait-tagged protein target, and the 10-fold lower molecular weight of the CaptorPrey protein compared to the antibody., Competing Interests: Declaration of Competing Interest K. Przytulski, P. Glaza, K. Brach, M. Sagan, G. Statkiewicz, J. Klajn, M. J. Walczak are employees and stockholders of Captor Therapeutics., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Purpose : The aim of this study was to evaluate the frequency of single nucleotide polymorphisms (SNP) of estrogen receptor genes ( ESR1 : rs12154178, rs1884054 and ESR2 : rs1268656, rs7159462) and to assess their possible influence on the clinical phenotype of primary open angle glaucoma (POAG). Methods : The study included 235 patients with POAG (143 patients with normal-tension glaucoma [NTG] and 92 patients with high-tension glaucoma [HTG]), and 165 healthy controls. DNA was isolated from peripheral blood, and SNP genotyping was performed using the Real-Time Polymerase Chain Reaction method to analyze the frequency of selected polymorphic variants of estrogen receptor genes. The clinical phenotype (best-corrected visual acuity, intraocular pressure [IOP], mean deviation [MD], cup to disc ratio, disc hemorrhages, notches, peripapillary atrophy, cold extremities) of participants were examined for association with the polymorphisms. Results : A similar frequency of the polymorphic variants of the studied genes was observed in patients with NTG, HTG and control group. Initial intraocular pressure was the lowest in NTG patients with GG variant of rs1268656 ( p = 0.044). The lowest maximal IOP in HTG patients was observed in CC variant of rs12154178 ( p = 0.039). Patients with HTG and CC variant of ESR1 polymorphism rs1884054 had the best visual acuity ( p = 0.009), similar tendency was also observed in the NTG group. This polymorphic variant of ESR1 gene in HTG was also related to earlier damage in visual field assessed according to MD values and higher percentage of notches. For rs12154178, homozygotic variant CC was related to earlier glaucoma damage according to MD in HTG patients ( p = 0.006). For polymorphism rs12154178, disc hemorrhages were found only for those with the AC variant. Cold extremities were most frequent in NTG patients with TT variant of rs1268656 comparing to other variants ( p = 0.021). Notches on optic disc were less frequent in patients with CC variant of rs12154178 of ERS-1 gene ( p = 0.022). Conclusions : The studied polymorphic variants of ESR1 and ESR2 genes may have an influence on the clinical phenotype of patients with POAG.

The membrane activity of some saponins, such as digitonin or alpha-hederin, is usually attributed to their interaction with membrane cholesterol (Chol). This contrasts with our recent publication showing that Chol, contrary to sphingomyelin (SM), can delay the cytotoxicity of the saponin ginsenoside Rh2, challenging the usual view that most saponins mediate their membrane effects through interaction with Chol. The aim of the present study was to elucidate the respective importance of Chol and SM as compared to phosphatidylcholine (PC) species in the membrane-related effects of Rh2. On simple lipid monolayers, Rh2 interacted more favorably with eggSM and DOPC than with Chol and eggPC. Using Large Unilamellar Vesicles (LUVs) of binary or ternary lipid compositions, we showed that Rh2 increased vesicle size, decreased membrane fluidity and induced membrane permeability with the following preference: eggSM:eggPC > eggSM:eggPC:Chol > eggPC:Chol. On Giant Unilamellar Vesicles (GUVs), we evidenced that Rh2 generated positive curvatures in eggSM-containing GUVs and small buds followed by intra-luminal vesicles in eggSM-free GUVs. Altogether, our data indicate that eggSM promotes and accelerates membrane-related effects induced by Rh2 whereas Chol slows down and depresses these effects. This study reconsiders the theory that Chol is the only responsible for the activity of saponins.

Under pathological conditions, cholesterol oxidation products (oxysterols) appear in enhanced concentration in blood and cerebrospinal fluid, which leads to cytotoxic effect, especially in central nervous system. However, the mode of action of oxysterols on the membrane level has not been fully resolved. In this paper we have investigated the interaction between 7α- hydroxycholesterol, 7α-OH (one of the most abundant oxysterol in human body) and two major membrane lipids: sphingomyelin, SM (basic component of lipid rafts and nerve membrane) and 1-palmitoyl-2-oleoyl-glycero-3-phosphocholine, POPC (main phospholipid of mammalian cell membranes). 7α-OH/SM mixtures may mimic pathologically changed lipid raft (ordered phase, L O ) while the SM/POPC system can model its surrounding (liquid-disordered phase, L α ). For our study, the Langmuir monolayer technique (based on registration of the surface pressure/area, π/A isotherms), complemented with surface visualization technique (Brewster angle microscopy, BAM) and theoretical calculations, have been employed. The observed affinity of 7α-OH to SM, which appears to be stronger than in cholesterol/SM system, indicates that cholesterol might be partially replaced in lipid rafts by its oxidized derivative. Its incorporation significantly increases rigidity of the system in relation to normal (cholesterol-containing) raft, which can disturb its proper functioning. On the other hand, the poor effect of this oxysterol on the raft's environment was observed., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Secretion of renin juxtaglomerular cells into bloodstream initiates activation of an enzymatic-hormonal cascade known as the RAAS (renin - angiotensin - aldosterone system). As a result, blood pressure is increased by the means several interrelated mechanisms. Mechanism of Zjednoczoaction of this system has been known for decades, but a few previously unknown components were recently added, such as ACE-2 and Ang(1-7), and their role often seems to be opposite to that of the conventional components. Local tissue systems also have important biological functions. They operate largely independently of the systemic activity, and their activity is observed primarily in the kidney, heart, in blood vessels, adrenal gland and nervous system. Angiotensin-2 (Ang-2), the main RAAS effector, has a wide scope of action, and thus abnormalities in its functioning have many consequences. Excessive activation is accompanied by chronic inflammation, as Ang-2 stimulates inflammatory mediators. As a result, degenerative processes and atherosclerosis are initiated. RAAS imbalance is associated with the most common diseases of civilization, such as cardio-vascular diseases, diabetes, kidney diseases, preeclampsia, osteoporosis and even neurodegenerative diseases. Many of these pathological processes are attributed to the excessive activation of tissue RA system. Therapeutic strategies based on inhibition of the RAAS are commonly used mainly in the treatment of hypertension and other cardiovascular disorders. The benefits of this class of drugs is primarily a decrease in blood pressure, but also the suppression of inflammatory processes and other pathological phenomena resulting from excessive activation of the RAAS. For that reason, some consider to use RAAS inhibitors in other diseases, e.g. Parkinson's disease. Further studies give hope for the improvement of RAAS inhibitor therapy and the development of new therapeutic strategies.

Osteochondroma is a benign bone tumor composed of a bony protrusion with an overlying cartilage cap. Osteochondromas arise in the scapula in 3% to 5% of cases, making them the most common benign bone tumor in this location. Scapular osteochondromas cause various pathologies of the shoulder girdle, including snapping scapula syndrome, chest wall deformity, shoulder impingement, and bursa formation. Bronchogenic cyst is an exceedingly rare finding in the periscapular area. It is a congenital cystic mass lined by tracheobronchial structures and respiratory epithelium. To our knowledge, there are no reports of a contiguous osteochondroma and bronchogenic cyst. A 12-month-old boy presented with an incidentally noted mass on the spine of the scapula, which drained scant, clear fluid through an adjacent pinprick-sized hole. Imaging revealed an exostosis with an adjacent cystic mass. The mass and cyst were excised en bloc, and histopathologic examination confirmed the diagnosis of osteochondroma with contiguous bronchogenic cyst. In this case, we present the report of a novel dual lesion.