Distinct from the complementary inhibition mechanism through binding to the target with three-dimensional conformation of small molecule inhibitors, targeted protein degradation technology takes tremendous advantage of endogenous protein degradation pathway inside cells to degrade plenty of “undruggable” target proteins, which provides a novel route for the treatment of many serious diseases, mainly including proteolysis-targeting chimeras, lysosome-targeting chimeras, autophagy-targeting chimeras, antibody-based proteolysis-targeting chimeras, etc. Unlike proteolysis-targeting chimeras first found in 2001, which rely on ubiquitin-proteasome system to mainly degrade intracellular proteins of interest, lysosome-targeting chimeras identified in 2020, which was act as the fastly developing technology, utilize cellular lysosomal pathway through endocytosis mediated by lysosome-targeting receptor to degrade both extracellular and membrane proteins. As an emerging biomedical technology, nucleic acid-driven lysosome-targeting chimeras utilize nucleic acids as certain components of chimera molecule to replace with ligand to lysosome-targeting receptor or protein of interest, exhibiting broad application prospects and potential clinical value in disease treatment and drug development. This review mainly introduced present progress of nucleic acid-driven lysosome-targeting chimeras technology, including its basic composition, its advantages compared with antibody or glycopeptide-based lysosome-targeting chimeras, and focused on its chief application, in terms of the type of lysosome-targeting receptors. Most research about the development of nucleic acid-driven lysosome-targeting chimeras focused on those which utilized cation-independent mannose-6-phosphonate receptor as the lysosome-targeting receptor. Both mannose-6-phosphonate-modified glycopeptide and nucleic aptamer targeting cation-independent mannose-6-phosphonate receptor, even double-stranded DNA molecule moiety can be taken advantage as the ligand to lysosome-targeting receptor. The same as classical lysosome-targeting chimeras, asialoglycoprotein receptor can also be used for advance of nucleic acid-driven lysosome-targeting chimeras. Another new-found lysosome-targeting receptor, scavenger receptor, can bind dendritic DNA molecules to mediate cellular internalization of complex and lysosomal degradation of target protein, suggesting the successful application of scavenger receptor-mediated nucleic acid-driven lysosome-targeting chimeras. In addition, this review briefly overviewed the history of lysosome-targeting chimeras, including first-generation and second-generation lysosome-targeting chimeras through cation-independent mannose-6-phosphonate receptor-mediated and asialoglycoprotein receptor-mediated endocytosis respectively, so that a clear timeline can be presented for the advance of chimera technique. Meantime, current deficiency and challenge of lysosome-targeting chimeras was also mentioned to give some direction for deep progress of lysosome-targeting chimeras. Finally, according to faulty lysosomal degradation efficiency, more cellular mechanism where lysosome-targeting chimeras perform degradation of protein of interest need to be deeply explored. In view of current progress and direction of nucleic acid-driven lysosome-targeting chimeras, we discussed its current challenges and development direction in the future. Stability of natural nucleic acid molecule and optimized chimera construction have a great influence on the biological function of lysosome-targeting chimeras. Discovery of novel lysosome-targeting receptors and nucleic aptamer with higher affinity to the target will greatly facilitate profound advance of chimera technique. In summary, nucleic acid-driven lysosome-targeting chimeras have many superiorities, such as lower immunogenicity, expedient synthesis of chimera molecules and so on, in contrast to classical lysosome-targeting chimeras, making it more valuable. Also, the chimera technology provides new ideas and methods for biomedical research, drug development and clinical treatment, and can be used more widely through further research and optimization.

OBJECTIVE To investigate the mechanism through which Danggui buxue decoction regulates neutrophil extracellular traps （NETs） to improve osteoporosis （OP） in rats with premature ovarian failure （POF）. METHODS Female SD rats were randomly divided into normal group， model group， calcitriol group， and Danggui buxue decoction low-dose， medium-dose and high-dose groups， with 9 rats in each group. Except for the normal group， all other groups were administered cisplatin via intraperitoneal injection on days 1 and 8 to establish a POF complicated with OP model. Each group received the corresponding drugs or normal saline intragastrically starting from day 5， once a day， for 4 consecutive weeks. After the last medication， serum levels of estradiol （E2）， NETs， 25-hydroxyvitamin D3 [25（OH）D3]， receptor activator of nuclear factor-κB ligand （RANKL）， and osteocalcin （BGP） were measured. The histopathological changes in bone tissue were observed. The expressions of vitamin D receptor （VDR）， myeloperoxidase （MPO）， neutrophil elastase （NE） and citrullinated histone H3 （CitH3） in bone tissue were detected； the protein expressions of 25-hydroxyvitamin D-1α-hydroxylase （CYP27B1） and 1α，25-dihydroxyvitamin D3-24-hydroxylase （CYP24A1） were also determined. RESULTS Compared with the normal group， the bone tissue of rats in the model group showed a significant reduction in the number of trabeculae， which was thinner broken and poorly connected， with significant destruction of the reticular structure， and an enlarged marrow cavity. Serum levels of NETs and RANKL， the protein expressions of MPO， NE， CitH3 and CYP24A1 in bone tissue were significantly increased or upregulated， while serum levels of E2， 25（OH）D3 and BGP as well as protein expressions of VDR and CYP27B1 were significantly decreased or downregulated （P＜0.05）. Compared with the model group， the histopathological changes in the bone tissue of rats in each administration group showed some degree of recovery， with significant improvements observed in most quantitative indicators （P＜0.05）. CONCLUSIONS Danggui buxue decoction can restore the E2 level in POF complicated with OP rats， and improve OP. The mechanism may be related to its ability to upregulate VD level and inhibit the formation of NETs.

AIM: To investigate the changes of retinal nerve fiber layer(RNFL)thickness, retinal thickness and blood flow density in different stages of diabetic retinopathy(DR)patients based on optical coherence tomography angiography(OCTA).METHODS: A retrospective analysis was conducted on 382 patients(382 eyes)diagnosed with DR in our hospital from February 2023 to February 2024. According to the staging criteria, the patients were divided into mild group(n=121), moderate group(n=133), severe group(n=72), and proliferative group(n=56). The general clinical data of the four groups of patients was compared; OCTA was used to scan and collect data from all patients, and the RNFL thickness, retinal thickness, and blood flow density were compared among the four groups of patients.RESULTS: There was no statistically significant difference in age, gender, hypertension, chronic kidney disease, and random blood glucose among patients in the mild, moderate, severe, and proliferative groups(all P>0.05). As the stage of DR worsened, the duration of the disease gradually prolonged(P<0.05). The thickness of the RNFL(superior, inferior, temporal, nasal, and average thickness)and retinal thickness significantly increased with the severity of DR(all P<0.001); however, there was no statistically significant difference in inferior RNFL thickness between the moderate and mild groups(P>0.05). The blood flow density in the superficial and deep retinal layers, as well as in the choroidal capillary layer, significantly decreased with the progression of DR(all P<0.05). Nevertheless, there was no statistically significant difference in superficial retinal blood flow density between the moderate and severe groups(P>0.05).CONCLUSION: OCTA can accurately observe the changes in RNFL thickness, retinal thickness, and blood flow density in patients with DR at different stages, which can serve as sensitive indicators for monitoring DR progression.

Background: In acute and chronic renal inflammatory diseases, the activation of inflammatory cells is involved in the defect of erythropoietin (EPO) production. Ras guanine nucleotide-releasing protein-4 (RasGRP4) promotes renal inflammatory injury in type 2 diabetes mellitus (T2DM). Our study aimed to investigate the role and mechanism of RasGRP4 in the production of renal EPO in diabetes. Methods: The degree of tissue injury was observed by pathological staining. Inflammatory cell infiltration was analyzed by immunohistochemical staining. Serum EPO levels were detected by enzyme-linked immunosorbent assay, and EPO production and renal interstitial fibrosis were analyzed by immunofluorescence. Quantitative real-time polymerase chain reaction and Western blotting were used to detect the expression of key inflammatory factors and the activation of signaling pathways. In vitro, the interaction between peripheral blood mononuclear cells (PBMCs) and C3H10T1/2 cells was investigated via cell coculture experiments. Results: RasGRP4 decreased the expression of hypoxia-inducible factor 2-alpha (HIF2A) via the ubiquitination–proteasome degradation pathway and promoted myofibroblastic transformation by activating critical inflammatory pathways, consequently reducing the production of EPO in T2DM mice. Conclusion RasGRP4 participates in the production of renal EPO in diabetic mice by affecting the secretion of proinflammatory cytokines in PBMCs, degrading HIF2A, and promoting the myofibroblastic transformation of C3H10T1/2 cells.

Background: In acute and chronic renal inflammatory diseases, the activation of inflammatory cells is involved in the defect of erythropoietin (EPO) production. Ras guanine nucleotide-releasing protein-4 (RasGRP4) promotes renal inflammatory injury in type 2 diabetes mellitus (T2DM). Our study aimed to investigate the role and mechanism of RasGRP4 in the production of renal EPO in diabetes. Methods: The degree of tissue injury was observed by pathological staining. Inflammatory cell infiltration was analyzed by immunohistochemical staining. Serum EPO levels were detected by enzyme-linked immunosorbent assay, and EPO production and renal interstitial fibrosis were analyzed by immunofluorescence. Quantitative real-time polymerase chain reaction and Western blotting were used to detect the expression of key inflammatory factors and the activation of signaling pathways. In vitro, the interaction between peripheral blood mononuclear cells (PBMCs) and C3H10T1/2 cells was investigated via cell coculture experiments. Results: RasGRP4 decreased the expression of hypoxia-inducible factor 2-alpha (HIF2A) via the ubiquitination–proteasome degradation pathway and promoted myofibroblastic transformation by activating critical inflammatory pathways, consequently reducing the production of EPO in T2DM mice. Conclusion RasGRP4 participates in the production of renal EPO in diabetic mice by affecting the secretion of proinflammatory cytokines in PBMCs, degrading HIF2A, and promoting the myofibroblastic transformation of C3H10T1/2 cells.

Background: In acute and chronic renal inflammatory diseases, the activation of inflammatory cells is involved in the defect of erythropoietin (EPO) production. Ras guanine nucleotide-releasing protein-4 (RasGRP4) promotes renal inflammatory injury in type 2 diabetes mellitus (T2DM). Our study aimed to investigate the role and mechanism of RasGRP4 in the production of renal EPO in diabetes. Methods: The degree of tissue injury was observed by pathological staining. Inflammatory cell infiltration was analyzed by immunohistochemical staining. Serum EPO levels were detected by enzyme-linked immunosorbent assay, and EPO production and renal interstitial fibrosis were analyzed by immunofluorescence. Quantitative real-time polymerase chain reaction and Western blotting were used to detect the expression of key inflammatory factors and the activation of signaling pathways. In vitro, the interaction between peripheral blood mononuclear cells (PBMCs) and C3H10T1/2 cells was investigated via cell coculture experiments. Results: RasGRP4 decreased the expression of hypoxia-inducible factor 2-alpha (HIF2A) via the ubiquitination–proteasome degradation pathway and promoted myofibroblastic transformation by activating critical inflammatory pathways, consequently reducing the production of EPO in T2DM mice. Conclusion RasGRP4 participates in the production of renal EPO in diabetic mice by affecting the secretion of proinflammatory cytokines in PBMCs, degrading HIF2A, and promoting the myofibroblastic transformation of C3H10T1/2 cells.

Background: In acute and chronic renal inflammatory diseases, the activation of inflammatory cells is involved in the defect of erythropoietin (EPO) production. Ras guanine nucleotide-releasing protein-4 (RasGRP4) promotes renal inflammatory injury in type 2 diabetes mellitus (T2DM). Our study aimed to investigate the role and mechanism of RasGRP4 in the production of renal EPO in diabetes. Methods: The degree of tissue injury was observed by pathological staining. Inflammatory cell infiltration was analyzed by immunohistochemical staining. Serum EPO levels were detected by enzyme-linked immunosorbent assay, and EPO production and renal interstitial fibrosis were analyzed by immunofluorescence. Quantitative real-time polymerase chain reaction and Western blotting were used to detect the expression of key inflammatory factors and the activation of signaling pathways. In vitro, the interaction between peripheral blood mononuclear cells (PBMCs) and C3H10T1/2 cells was investigated via cell coculture experiments. Results: RasGRP4 decreased the expression of hypoxia-inducible factor 2-alpha (HIF2A) via the ubiquitination–proteasome degradation pathway and promoted myofibroblastic transformation by activating critical inflammatory pathways, consequently reducing the production of EPO in T2DM mice. Conclusion RasGRP4 participates in the production of renal EPO in diabetic mice by affecting the secretion of proinflammatory cytokines in PBMCs, degrading HIF2A, and promoting the myofibroblastic transformation of C3H10T1/2 cells.

Small interfering RNA (siRNA) has a promising future in the treatment of ocular diseases due to its high efficiency, specificity, and low toxicity in inhibiting the expression of target genes and proteins. However, due to the unique anatomical structure of the eye and various barriers, delivering nucleic acids to the retina remains a significant challenge. In this study, we rationally design PACD, an A-B-C type non-viral vector copolymer composed of a hydrophilic PEG block (A), a siRNA binding block (B) and a pH-responsive block (C). PACDs can self-assemble into nanosized polymeric micelles that compact siRNAs into polyplexes through simple mixing. By evaluating its pH-responsive activity, gene silencing efficiency in retinal cells, intraocular distribution, and anti-angiogenesis therapy in a mouse model of hypoxia-induced angiogenesis, we demonstrate the efficiency and safety of PACD in delivering siRNA in the retina. We are surprised to discover that, the PACD/siRNA polyplexes exhibit remarkable intracellular endosomal escape efficiency, excellent gene silencing, and inhibit retinal angiogenesis. Our study provides design guidance for developing efficient nonviral ocular nucleic acid delivery systems.

Objective To evaluate the auxiliary diagnostic value of T cells spot test of Mycobacterium tuberculosis infection (T-SPOT.TB) for pulmonary and extra-pulmonary tuberculosis among the elderly. Methods A total of 173 elderly patients at ages of 60 years and older and with suspected tuberculosis that were admitted to People’s Hospital of Xinjiang Uygur Autonomous Region during the period from October 2022 through February 2024 were enrolled, and all patients underwent T-SPOT.TB, acid fast staining and GeneXpert MTB/RIF tests. The etiological tests of MTB served as a gold standard, and the diagnostic values of T-SPOT.TB, acid fast staining and GeneXpert MTB/RIF tests for pulmonary and extra-pulmonary tuberculosis were compared among the elderly patients. Results Of the 173 elderly patients suspected of tuberculosis, there were 44 patients definitely diagnosed with pulmonary tuberculosis, 30 cases with extra-pulmonary tuberculosis, and 99 cases without tuberculosis. The sensitivities of T-SPOT.TB, acid fast staining and GeneXpert MTB/RIF tests were 86.5%, 27.0% and 54.1% for diagnosis of tuberculosis. The sensitivities of T-SPOT.TB were 86.4% and 86.7% for diagnosis of pulmonary tuberculosis and extra-pulmonary tuberculosis, with an 80.8% specificity for diagnosis of tuberculosis. The sensitivities of GeneXpert MTB/RIF were 56.8% and 50.0% for diagnosis of pulmonary tuberculosis and extra-pulmonary tuberculosis, with a 100.0% specificity each, and the sensitivities of acid fast staining were 31.8% and 20.0% for diagnosis of pulmonary tuberculosis and extra-pulmonary tuberculosis, with a 100.0% specificity each. In addition, the areas under the receiver operating characteristic curve were 0.836, 0.635 and 0.770 for diagnosis of tuberculosis with T-SPOT.TB, acid fast staining and GeneXpert MTB/RIF tests among the elderly patients, respectively. Conclusion T-SPOT.TB has a high auxiliary diagnostic value for both pulmonary and extra-pulmonary tuberculosis among elderly patients.

ObjectiveIt was reported that the transthyretin (TTR) has a neuroprotective effect on Alzheimer’s disease (AD), which is manifested by the ability of TTR to inhibit the pathological aggregation of amyloid beta protein (Aβ). In this work, we investigated the mechanism of the interactions between TTR and Aβ at the molecular level to reveal the neuroprotective effect of TTR on AD. MethodsProtein-protein docking was used to explore the models of interaction between different structural forms of TTR and Aβ, and molecular dynamics simulation was further applied to investigate the dynamic process of the interaction between the two. ResultsBoth TTR tetramer and monomer can interact with Aβ monomer, and the thyroxine-binding channel of TTR tetramer is the main binding site of Aβ monomer. In addition, the EF helix and EF loop of TTR tetramer were also able to bind Aβ monomer. When the TTR tetramer dissociates, the hydrophobic site of the internal TTR monomer is exposed, which has a strong affinity for Aβ monomer. For the interaction between Aβ aggregates and TTR, a higher degree of aggregation can be formed between TTR monomer and Aβ aggregates due to the β-sheet-rich property of TTR monomer and Aβ aggregates, which may therefore reduce the cytotoxicity of Aβ aggregates. ConclusionBoth TTR tetramer and monomer can inhibit Aβ aggregation by “sequestering” Aβ monomer, while TTR monomer can reduce the cytotoxicity of Aβ aggregates by forming large co-aggregation with Aβ aggregates. This work can provide an important theoretical basis for the design and discovery of anti-AD drugs based on the neuroprotective effects of TTR.