Ultrasound propagation characteristics within the bone tissue of miniature ultrasound probes: implications for the spinal navigation of pedicle screw placement.

Background: The accuracy of pedicle screw fixation is crucial for patient safety. Traditional navigation methods based on computed tomography (CT) imaging have several limitations. Therefore, this study aimed to investigate the ultrasonic propagation characteristics of bone tissue and their relationship with CT imaging results, as well as the potential application of ultrasound navigation in pedicle screw fixation. Methods: The study used three bovine spine specimens (BSSs) and five human vertebral allograft bones (HABs) to progressively decrease the thickness of the cancellous bone layer, simulating the process of pedicle screw perforation. Five unfocused miniature ultrasound probes with frequencies of 2.2, 2.5, 3, 12, and 30 MHz were employed for investigating the ultrasonic propagation characteristics of cancellous and cortical bone through ultrasound transmission and backscatter experiments. The CT features of the bone tissue was obtained with the Skyscan 1174 micro-CT scanner (Bruker, Billerica, MA, USA). Results: The experimental results demonstrated that low-frequency (2-3 MHz) ultrasound effectively penetrated the cancellous bone layer up to a depth of approximately 5 mm, with an attenuation coefficient below 10 dB/cm. Conversely, high-frequency (12 MHz) ultrasound exhibited significant signal attenuation in cancellous bone, reaching up to 55.8 dB/cm. The amplitude of the backscattered signal at the cancellous bone interface exhibited a negative correlation with the bone sample thickness (average r=-0.84), meaning that as the thickness of the cancellous bone layer on the cortical bone decreases, the backscattered signal amplitude gradually increases (P<0.05). Upon reaching the cortical bone interface, there was a rapid surge in echo signal amplitude, up to 8 times higher. Meanwhile, the statistical results indicated a significant correlation between the amplitude of the echo signal and the micro-CT scanning results of bone trabecular structure. Conclusions: Theoretically, using multiple ultrasonic probes (≥3) and regions of interest (ROIs) (≥5) has the potential to provide surgeons with early warning signals for pedicle perforation based on three or more successive increases in echo signal amplitude or a sudden substantial increase. The statistical results indicate a significant correlation between the amplitude of the echo signal and the micro-CT scanning results of bone trabeculae, suggesting the potential use of ultrasound as opposed to CT for real-time intraoperative bone navigation.

Meta Learning with Attention Based FP-GNNs for Few-Shot Molecular Property Prediction.

Molecular property prediction holds significant importance in drug discovery, enabling the identification of biologically active compounds with favorable drug-like properties. However, the low data problem, arising from the scarcity of labeled data in drug discovery, poses a substantial obstacle for accurate predictions. To address this challenge, we introduce a novel architecture, AttFPGNN-MAML, for few-shot molecular property prediction. The proposed approach incorporates a hybrid feature representation to enrich molecular representations and model intermolecular relationships specific to the task. By leveraging ProtoMAML, a meta-learning strategy, our model is trained and adapted to new tasks. Evaluation on two few-shot data sets, MoleculeNet and FS-Mol, demonstrates our method's superior performance in three out of four tasks and across various support set sizes. These results convincingly validate the effectiveness of our method in the realm of few-shot molecular property prediction. The source code is publicly available at https://github.com/sanomics-lab/AttFPGNN-MAML.

Synthetically Feasible De Novo Molecular Design of Leads Based on a Reinforcement Learning Model: AI-Assisted Discovery of an Anti-IBD Lead Targeting CXCR4.

Artificial intelligence (AI) de novo molecular generation provides leads with novel structures for drug discovery. However, the target affinity and synthesizability of the generated molecules present critical challenges for the successful application of AI technology. Therefore, we developed an advanced reinforcement learning model to bridge the gap between the theory of de novo molecular generation and the practical aspects of drug discovery. This model utilizes chemical reaction templates and commercially available building blocks as a starting point and employs forward reaction prediction to generate molecules, while real-time docking and drug-likeness predictions are conducted to ensure synthesizability and drug-likeness. We applied this model to design active molecules targeting the inflammation-related receptor CXCR4 and successfully prepared them according to the AI-proposed synthetic routes. Several molecules exhibited potent anti-CXCR4 and anti-inflammatory activity in subsequent in vitro and in vivo assays. The top-performing compound XVI alleviated symptoms related to inflammatory bowel disease and showed reasonable pharmacokinetic properties.

Prediction of developmental toxic effects of fine particulate matter (PM2.5) water-soluble components via machine learning through observation of PM2.5 from diverse urban areas.

The global health implications of fine particulate matter (PM2.5) underscore the imperative need for research into its toxicity and chemical composition. In this study, zebrafish embryos exposed to the water-soluble components of PM2.5 from two cities (Harbin and Hangzhou) with differences in air quality, underwent microscopic examination to identify primary target organs. The Harbin PM2.5 induced dose-dependent organ malformation in zebrafish, indicating a higher level of toxicity than that of the Hangzhou sample. Harbin PM2.5 led to severe deformities such as pericardial edema and a high mortality rate, while the Hangzhou sample exhibited hepatotoxicity, causing delayed yolk sac absorption. The experimental determination of PM2.5 constituents was followed by the application of four algorithms for predictive toxicological assessment. The random forest algorithm correctly predicted each of the effect classes and showed the best performance, suggesting that zebrafish malformation rates were strongly correlated with water-soluble components of PM2.5. Feature selection identified the water-soluble ions F- and Cl- and metallic elements Al, K, Mn, and Be as potential key components affecting zebrafish development. This study provides new insights into the developmental toxicity of PM2.5 and offers a new approach for predicting and exploring the health effects of PM2.5.

Retinoic acid alleviates the reduction of Akt and Bad phosphorylation and regulates Bcl-2 family protein interactions in animal models of ischemic stroke.

Ischemic stroke causes a lack of oxygen and glucose supply to brain, eventually leads to severe neurological disorders. Retinoic acid is a major metabolic product of vitamin A and has various biological effects. The PI3K-Akt signaling pathway is an important survival pathway in brain. Phosphorylated Akt is important in regulating survival and apoptosis. We examined whether retinoic acid has neuroprotective effects in stroke model by regulating Akt and its downstream protein, Bad. Moreover, we investigated the relationship between retinoic acid and Bcl-2 family protein interactions. Animals were intraperitoneally administered vehicle or retinoic acid (5 mg/kg) for four days before surgery and ischemic stroke was induced by middle cerebral artery occlusion (MCAO) surgery. Neurobehavioral tests were performed 24 h after MCAO and cerebral cortical tissues were collected. Cresyl violet staining and TUNEL histochemistry were performed, Western blot and immunoprecipitation analysis were performed to elucidate the expression of various proteins. Retinoic acid reduced neurological deficits and histopathological changes, decreased the number of TUNEL-positive cells, and alleviated reduction of phospho-PDK1, phospho-Akt, and phospho-Bad expression caused by MCAO damage. Immunoprecipitation analysis showed that MCAO damage reduced the interaction between phospho-Bad and 14-3-3, which was attenuated by retinoic acid. Furthermore, retinoic acid mitigated the increase in Bcl-2/Bad and Bcl-xL/Bad binding levels and the reduction in Bcl-2/Bax and Bcl-xL/Bax binding levels caused by MCAO damage. Retinoic acid alleviated MCAO-induced increase of caspase-3 and cleaved caspase-3 expression. We demonstrate that retinoic acid prevented apoptosis against cerebral ischemia through phosphorylation of Akt and Bad, maintenance of phospho-Bad and 14-3-3 binding, and regulation of Bcl-2 family protein interactions. .

Levels of antibodies against the monkeypox virus compared by HIV status and historical smallpox vaccinations: a serological study.

Men who have sex with men and people living with HIV are disproportionately affected in the 2022 multi-country monkeypox epidemic. The smallpox vaccine can induce cross-reactive antibodies against the monkeypox virus (MPXV) and reduce the risk of infection. Data on antibodies against MPXV induced by historic smallpox vaccination in people with HIV are scarce. In this observational study, plasma samples were collected from people living with and without HIV in Shenzhen, China. We measured antibodies binding to two representative proteins of vaccinia virus (VACV; A27L and A33R) and homologous proteins of MPXV (A29L and A35R) using an enzyme-linked immunosorbent assay. We compared the levels of these antibodies between people living with and without HIV. Stratified analyses were performed based on the year of birth of 1981 when the smallpox vaccination was stopped in China. Plasma samples from 677 people living with HIV and 746 people without HIV were tested. A consistent pattern was identified among the four antibodies, regardless of HIV status. VACV antigen-reactive and MPXV antigen-reactive antibodies induced by historic smallpox vaccination were detectable in the people born before 1981, and antibody levels reached a nadir during or after 1981. The levels of smallpox vaccine-induced antibodies were comparable between people living with HIV and those without HIV. Our findings suggest that the antibody levels against MPXV decreased in both people living with and without HIV due to the cessation of smallpox vaccination.

MolProphet: A One-Stop, General Purpose, and AI-Based Platform for the Early Stages of Drug Discovery.

Artificial intelligence (AI) is an effective tool to accelerate drug discovery and cut costs in discovery processes. Many successful AI applications are reported in the early stages of small molecule drug discovery. However, most of those applications require a deep understanding of software and hardware, and focus on a single field that implies data normalization and transfer between those applications is still a challenge for normal users. It usually limits the application of AI in drug discovery. Here, based on a series of robust models, we formed a one-stop, general purpose, and AI-based drug discovery platform, MolProphet, to provide complete functionalities in the early stages of small molecule drug discovery, including AI-based target pocket prediction, hit discovery and lead optimization, and compound targeting, as well as abundant analyzing tools to check the results. MolProphet is an accessible and user-friendly web-based platform that is fully designed according to the practices in the drug discovery industry. The molecule screened, generated, or optimized by the MolProphet is purchasable and synthesizable at low cost but with good drug-likeness. More than 400 users from industry and academia have used MolProphet in their work. We hope this platform can provide a powerful solution to assist each normal researcher in drug design and related research areas. It is available for everyone at https://www.molprophet.com/.

Artificial Intelligence-Assisted Optimization of Antipigmentation Tyrosinase Inhibitors: De Novo Molecular Generation Based on a Low Activity Lead Compound.

Artificial intelligence (AI) de novo molecular generation is a highly promising strategy in the drug discovery, with deep reinforcement learning (RL) models emerging as powerful tools. This study introduces a fragment-by-fragment growth RL forward molecular generation and optimization strategy based on a low activity lead compound. This process integrates fragment growth-based reaction templates, while target docking and drug-likeness prediction were simultaneously performed. This comprehensive approach considers molecular similarity, internal diversity, synthesizability, and effectiveness, thereby enhancing the quality and efficiency of molecular generation. Finally, a series of tyrosinase inhibitors were generated and synthesized. Most compounds exhibited more improved activity than lead, with an optimal candidate compound surpassing the effects of kojic acid and demonstrating significant antipigmentation activity in a zebrafish model. Furthermore, metabolic stability studies indicated susceptibility to hepatic metabolism. The proposed AI structural optimization strategies will play a promising role in accelerating the drug discovery and improving traditional efficiency.

Retinoic acid attenuates ischemic injury-induced activation of glial cells and inflammatory factors in a rat stroke model.

Stroke is a leading cause of death and long-term disability which can cause oxidative damage and inflammation of the neuronal cells. Retinoic acid is an active metabolite of vitamin A that has various beneficial effects including antioxidant and anti-inflammatory effects. In this study, we investigated whether retinoic acid modulates oxidative stress and inflammatory factors in a stroke animal model. A middle cerebral artery occlusion (MCAO) was performed on adult male rats to induce focal cerebral ischemia. Retinoic acid (5 mg/kg) or vehicle was injected into the peritoneal cavity for four days before MCAO surgery. The neurobehavioral tests were carried out 24 h after MCAO and cerebral cortex tissues were collected. The cortical damage was assessed by hematoxylin-eosin staining and reactive oxygen species assay. In addition, Western blot and immunohistochemical staining were performed to investigate the activation of glial cells and inflammatory cytokines in MCAO animals. Ionized calcium-binding adapter molecule-1 (Iba-1) and glial fibrillary acidic protein (GFAP) were used as markers of microglial and astrocyte activation, respectively. Tumor necrosis factor-α (TNF-α) and interleukin-1ß (IL-1ß) were used as representative pro-inflammatory cytokines. Results showed that MCAO damage caused neurobehavioral defects and histopathological changes in the ischemic region and increased oxidative stress. Retinoic acid treatment reduced these changes caused by MCAO damage. We detected increases in Iba-1 and GFAP in MCAO animals treated with vehicle. However, retinoic acid alleviated increases in Iba-1 and GFAP caused by MCAO damage. Moreover, MCAO increased levels of nuclear factor-κB and pro-inflammatory cytokines, including TNF-α and IL-1ß. Retinoic acid alleviated the expression of these inflammatory proteins. These findings elucidate that retinoic acid regulates microglia and astrocyte activation and modulates pro-inflammatory cytokines. Therefore, this study suggests that retinoic acid exhibits strong antioxidant and anti-inflammatory properties by reducing oxidative stress, inhibiting neuroglia cell activation, and preventing the increase of pro-inflammatory cytokines in a cerebral ischemia.

Epigallocatechin gallate improves neuronal damage in animal model of ischemic stroke and glutamate-exposed neurons via modulation of hippocalcin expression.

Epigallocatechin gallate (EGCG) is a polyphenolic component of green tea that has anti-oxidative and anti-inflammatory effects in neurons. Ischemic stroke is a major neurological disease that causes irreversible brain disorders. It increases the intracellular calcium concentration and induces apoptosis. The regulation of intracellular calcium concentration is important to maintain the function of the nervous system. Hippocalcin is a neuronal calcium sensor protein that controls intracellular calcium concentration. We investigated whether EGCG treatment regulates the expression of hippocalcin in stroke animal model and glutamate-induced neuronal damage. We performed middle cerebral artery occlusion (MCAO) to induce cerebral ischemia. EGCG (50 mg/kg) or phosphate buffered saline was injected into the abdominal cavity just before MCAO surgery. The neurobehavioral tests were performed 24 h after MCAO surgery and cerebral cortex tissue was collected. MCAO damage induced severe neurobehavioral disorders, increased infarct volume, and decreased the expression of hippocalcin in the cerebral cortex. However, EGCG treatment improved these deficits and alleviated the decrease in hippocalcin expression in cerebral cortex. In addition, EGCG dose-dependently alleviated neuronal cell death and intracellular calcium overload in glutamate-exposed neurons. Glutamate exposure reduced hippocalcin expression, decreased Bcl-2 expression, and increased Bax expression. However, EGCG treatment mitigated these changes caused by glutamate toxicity. EGCG also attenuated the increase in caspase-3 and cleaved caspase-3 expressions caused by glutamate exposure. The effect of EGCG was more pronounced in non-transfected cells than in hippocalcin siRNA-transfected cells. These findings demonstrate that EGCG protects neurons against glutamate toxicity through the regulation of Bcl-2 family proteins and caspase-3. It is known that hippocalcin exerts anti-apoptotic effect through the modulation of apoptotic pathway. Thus, we can suggest evidence that EGCG has a neuroprotective effect by regulating hippocalcin expression in ischemic brain damage and glutamate-exposed cells.

Chlorogenic acid regulates the expression of protein phosphatase 2A subunit B in the cerebral cortex of a rat stroke model and glutamate-exposed neurons.

BACKGROUND: Ischemic stroke is a serious neurological disorder caused by blockages in cerebral artery. Protein phosphatase 2A (PP2A) is a phosphatase that performs a critical role in cell signaling and growth. PP2A subunit B acts as a neuroprotective agent in the nerve system. Chlorogenic acid, which is mainly found in roasted coffee, has antioxidant, anti-inflammatory, and anti-apoptotic effects. We hypothesized that chlorogenic acid modulates PP2A subunit B expression in ischemic stroke models and glutamate-mediated neurons. Middle artery occlusion (MCAO) surgery was operated and chlorogenic acid (30 mg/kg) or phosphate buffer saline was treated 2 h after MCAO. The cerebral cortex was collected 24 h after surgery and the change of PP2A subunit B expression was analyzed. Glutamate and/or chlorogenic acid were treated in cultured neurons, further study was performed. RESULTS: A decrease in PP2A subunit B expression in MCAO animals was identified. Chlorogenic acid alleviated this decrease due to ischemic injury. Moreover, the number of PP2A subunit B-positive cells in the ischemic cerebral cortex was significantly decreased, chlorogenic acid alleviated this decrease. We also found protective effects of chlorogenic acid in neurons exposed to glutamate. Glutamate decreased the expression of PP2A subunit B and chlorogenic acid mitigated this decrease. Our results elucidated that chlorogenic acid performs neuroprotective functions and attenuates the reduction of PP2A subunit B by brain damage and glutamate-mediated excitotoxicity. CONCLUSIONS: We showed that chlorogenic acid attenuated the decrease of PP2A subunit B in ischemic injury and neurons exposed to glutamate. Since PP2A subunit B contributes to the protection of brain tissue, we can suggest that chlorogenic acid preserves neurons by modulating PP2A subunit B during ischemic damage.

Modulation of thioredoxin by chlorogenic acid in an ischemic stroke model and glutamate-exposed neurons.

Ischemic stroke increases the production of reactive oxygen species (ROS), which can eventually lead to neuronal death. Thioredoxin is a small reductase protein that acts as an eliminator of ROS and protects neurons from brain damage. Chlorogenic acid is known as a phenolic compound that has a neuroprotective effect. We investigated the change of thioredoxin expression by chlorogenic acid in a middle cerebral artery occlusion (MCAO) animal model. Adult rats were injected intraperitoneally with phosphate buffered saline or chlorogenic acid (30 mg/kg) 2 h after MCAO. MCAO damage induced neurological defects and increased ROS and lipid peroxidation levels, however, chlorogenic acid mitigated these changes. MCAO damage reduced thioredoxin expression, which was mitigated by chlorogenic acid treatment. The interaction between thioredoxin and apoptosis signal-regulating kinase 1 (ASK1) was decreased in MCAO animals, chlorogenic acid treatment prevented this decrease. In cultured neurons, chlorogenic acid dose-dependently attenuated glutamate-induced decreases in cell viability and thioredoxin expression. Glutamate toxicity downregulated bcl-2 and upregulated bax, cytochrome c, and caspase-3, however, chlorogenic acid attenuated these changes. The mitigating effect of chlorogenic acid was lower in thioredoxin siRNA-transfected cells than in non-transfected cells. These results provide evidence that chlorogenic acid exerts potent antioxidant and neuroprotective effects through regulation of thioredoxin and modulation of ASK1 and thioredoxin binding in ischemic brain injury. These findings indicate that chlorogenic acid exerts a neuroprotective effect by regulating thioredoxin expression in cerebral ischemia and glutamate exposure conditions.

Effect of polystyrene nanoplastics exposure on gene expression and pathogenesis of zoonotic pathogen, Edwardsiella piscicida.

A surge in the number of anthropogenic pollutants has been caused by increasing industrial activities. Nanoplastics are spotlighted as a new aquatic pollutant that are a threat to microbes and larger organisms. Our previous study showed that the subinhibitory concentrations of aquatic pollutants such as phenol and formalin act as signaling molecules and modulate global gene expression and metabolism. In this study, we aimed to investigate the impact of a new type of anthropogenic contaminant, polystyrene (PS) nanoplastics, on the expression of key virulence factors in zoonotic pathogen Edwardsiella piscicida and the assessment of potential changes in the susceptibility of zebrafish as a model host. The TEM data indicated a noticeable change in the cell membrane indicating that PS particles were possibly entering the bacterial cells. Transcriptome analyses performed to identify the differentially expressed genes upon PS exposure revealed that the genes involved in major virulence factor type VI secretion system (T6SS) were down-regulated. However, the expression of T6SS-related genes was recovered from the PS adapted E. piscicida when nanoplastics are free. This demonstrated the hypervirulence of pathogen in infection assays with both cell lines and in vivo zebrafish model. Therefore, this study provides experimental evidence elucidating the direct regulatory impact of nanoplastics influx into aquatic ecosystems on fish pathogenic bacteria, notably influencing the expression of virulence factors.

The cryo-EM structure of homotetrameric attachment glycoprotein from langya henipavirus.

Langya Henipavirus (LayV) infection is an emerging zoonotic disease that has been causing respiratory symptoms in China since 2019. For virus entry, LayV's genome encodes the fusion protein F and the attachment glycoprotein G. However, the structural and functional information regarding LayV-G remains unclear. In this study, we revealed that LayV-G cannot bind to the receptors found in other HNVs, such as ephrin B2/B3, and it shows different antigenicity from HeV-G and NiV-G. Furthermore, we determined the near full-length structure of LayV-G, which displays a distinct mushroom-shaped configuration, distinguishing it from other attachment glycoproteins of HNV. The stalk and transmembrane regions resemble the stem and root of mushroom and four downward-tilted head domains as mushroom cap potentially interact with the F protein and influence membrane fusion process. Our findings enhance the understanding of emerging HNVs that cause human diseases through zoonotic transmission and provide implication for LayV related vaccine development.

Striking antibody evasion of SARS-CoV-2 Omicron sub-lineages BQ.1.1, XBB.1 and CH.1.1.

An intelligent indoor metasurface robotic is empowered on the physical layer by programmable metasurfaces and on the cyber layer by artificial-intelligence tools.

Circ-NFKB1 sponges miR-203a-5p to regulate ERBB4 expression and promotes IL-1ß induced chondrocytes apoptosis.

BACKGROUND: Osteoarthritis (OA) is a chronic disease of the bones and joints that commonly affects middle-aged and elderly individuals, characterized by the degeneration of articular cartilage and inflammation of the joints. The molecular mechanisms of OA urgently need to be further examined. Our study intended to uncover circ-NFKB1/miR-203a-5p/ERBB4 axis in regulating interleukin-1ß (IL-1ß) induced chondrocytes apoptosis. METHODS: GSE178724, GSE79258 and GSE169077 were downloaded from Gene Expression Omibus (GEO) database and differentially expressed circRNAs, miRNAs and mRNAs were obtained by R software. Annexin V assay was used to determine cell apoptosis rate. ELISA was further performed to identify the inflammation response. Dual-luciferase reporter gene assay was conducted to examine the combination among circ-NFKB1, miR-203a-5p and ERBB4. RESULTS: Our research demonstrated that circ-NFKB1 and ERBB4 were significantly upregulated through bioinformatic analysis. MiR-203a-5p was significantly downregulated through bioinformatic analysis. Silencing of circ-NFKB1 notably inhibited the IL-1ß induced chondrocytes apoptosis and upregulated ERBB4 expression. Through prediction on bioinformatics analysis, miR-203a-5p was the target binding circ-NFKB1, and ERBB4 was the potential target of miR-203a-5p. Subsequently, these changes induced by the silencing of circ-NFKB1 were reversed upon addition of pcDNA/ERBB4. CONCLUSIONS: Silencing circ-NFKB1 could sponge miR-203a-5p to regulate ERBB4 expression and alleviate OA progression.

Efficacy and safety of Kumpe access catheter for pre-percutaneous nephrolithotomy renal access in modified supine percutaneous nephrolithotomy.

INTRODUCTION: Traditionally, a pigtail catheter (PCN) is placed for preoperative renal access before performing percutaneous nephrolithotomy (PCNL). However, PCN can hamper the passage of the guidewire to the ureter, due to which, access tract can be lost. Therefore, Kumpe Access Catheter (KMP) has been proposed for preoperative renal access before PCNL. In this study, we analyzed the efficacy and safety of KMP for surgical outcomes in modified supine PCNL compared to those in PCN. MATERIALS AND METHODS: From July 2017 to December 2020, 232 patients underwent modified supine PCNL at a single tertiary center, of which 151 patients were enrolled in this study after excluding patients who underwent bilateral surgery, multiple punctures, or combined operations. Enrolled patients were divided into two groups according to the type of pre-PCNL nephrostomy catheter used: PCN versus KMP. A pre-PCNL nephrostomy catheter was selected based on the radiologist's preference. A single surgeon performed all PCNL procedures. Patient characteristics and surgical outcomes, including stone-free rate, operation time, radiation exposure time (RET), and complications, were compared between the two groups. RESULTS: Of the 151 patients, 53 underwent PCN placement, and 98 underwent KMP placement for pre-PCNL nephrostomy. Patient baseline characteristics were comparable between the two groups, except for the renal stone type and multiplicity. The operation time, stone-free rate, and complication rate were not significantly different between the two groups; however, RET was significantly shorter in the KMP group. CONCLUSION: The surgical outcomes of KMP placement were comparable to those of PCN and showed shorter RET during modified supine PCNL. Based on our results, we recommend KMP placement for pre-PCNL nephrostomy, particularly for reducing RET during supine PCNL.

Neuroprotective effects of chlorogenic acid by controlling the Bcl-2 family protein in a stroke animal model.

Ischemic stroke causes severe brain damage and high mortality. Chlorogenic acid is a phenolic compound that has neuroprotective properties. B-cell lymphoma-2 (Bcl-2) family proteins are important for apoptosis regulation. Bcl-2 and Bcl-xL are proteins that inhibit apoptosis, and Bax and Bad induce apoptosis. In this study, we investigated whether chlorogenic acid exerts a neuroprotective effect against ischemic stroke damage by regulating Bcl-2 family proteins. We performed middle cerebral artery occlusion (MCAO) to induce ischemic stroke in adult male rats. The animals were intraperitoneally injected with normal saline as a vehicle or chlorogenic acid (30 mg/kg) 2 hr after MCAO. Cerebral cortex tissue was collected 24 hr after MCAO damage. MCAO damage caused histopathological changes and increased the number of terminal deoxynucleotidyl transferase deoxyuridine triphosphate (dUTP) nick end labeling-positive cells, while chlorogenic acid attenuated these changes. RT-qPCR and Western blot results showed decreases in Bcl-2 and Bcl-xL expression and an increase in Bax and Bad expression in MCAO animals. However, chlorogenic acid treatment attenuated these changes due to MCAO damage. The interaction of Bax with Bcl-2 or Bcl-xL decreased in MCAO animals, and the binding of Bad with Bcl-2 or Bcl-xL increased. However, chlorogenic acid treatment reduced these changes. Chlorogenic acid also prevented MCAO-induced increases in caspase-3 and caspase-9 expression. This study provides evidence that chlorogenic acid has neuroprotective effects against MCAO damage by modulating Bcl-2 family proteins including Bcl-2, Bcl-xL, Bax, and Bad. Furthermore, chlorogenic acid regulates the interaction between Bcl-2 family proteins. In conclusion, chlorogenic acid contributes to neuroprotection against ischemic stroke damage by controlling Bcl-2 family proteins.

Identification of proteins regulated by chlorogenic acid in an ischemic animal model: a proteomic approach.

BACKGROUND: Cerebral ischemia is a serious neurological disorder that can lead to high morbidity and mortality. Chlorogenic acid is a polyphenol compound with antioxidant that can regulate proteins in cerebral ischemia. Middle cerebral artery occlusion (MCAO) surgery was performed to induce ischemic brain injury and was maintained for 24 h. Chlorogenic acid (30 mg/kg) or vehicle was administrated into the peritoneal cavity 2 h after MCAO surgery. The cerebral cortical tissues were collected for further study and a proteomic approach was performed to identify the proteins changed by chlorogenic acid in the MCAO animals. RESULTS: We found that chlorogenic acid alleviated in changes in adenosylhomocysteinase, glycerol-3-phosphate dehydrogenase, eukaryotic translation initiation factor 4A-II, apolipoprotein A-I, and mu-crystallin. These proteins were reduced in MCAO animals with vehicle, and these reductions were attenuated by chlorogenic acid treatment. The mitigation of this reduction by chlorogenic acid was confirmed by the reverse transcription PCR technique. These proteins are associated with energy metabolism, protein synthesis, inflammation, and physiological metabolism. They are involved in the neuroprotective effect of chlorogenic acid. These results showed that chlorogenic acid alleviates the neurological disorders caused by MCAO and regulates the expression of proteins involved in neuroprotection. CONCLUSIONS: Therefore, our findings provide evidence that chlorogenic acid plays a neuroprotective role in stroke animal models by controlling specific proteins.

Omicron BQ.1.1 and XBB.1 unprecedentedly escape broadly neutralizing antibodies elicited by prototype vaccination.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron subvariants have seriously attacked the antibody barrier established by natural infection and/or vaccination, especially the recently emerged BQ.1.1 and XBB.1. However, crucial mechanisms underlying the virus escape and the broad neutralization remain elusive. Here, we present a panoramic analysis of broadly neutralizing activity and binding epitopes of 75 monoclonal antibodies isolated from prototype inactivated vaccinees. Nearly all neutralizing antibodies (nAbs) partly or totally lose their neutralization against BQ.1.1 and XBB.1. We report a broad nAb, VacBB-551, that effectively neutralizes all tested subvariants including BA.2.75, BQ.1.1, and XBB.1. We determine the cryoelectron microscopy (cryo-EM) structure of VacBB-551 complexed with the BA.2 spike and perform detailed functional verification to reveal the molecular basis of N460K and F486V/S mutations mediating the partial escape of BA.2.75, BQ.1.1, and XBB.1 from the neutralization of VacBB-551. Overall, BQ.1.1 and XBB.1 raised the alarm over SARS-CoV-2 evolution with unprecedented antibody evasion from broad nAbs elicited by prototype vaccination.