Isorhamnetin Alleviates Mitochondrial Injury in Severe Acute Pancreatitis via Modulation of KDM5B/HtrA2 Signaling Pathway.

Severe acute pancreatitis (SAP), a widespread inflammatory condition impacting the abdomen with a high mortality rate, poses challenges due to its unclear pathogenesis and the absence of effective treatment options. Isorhamnetin (ISO), a naturally occurring flavonoid, demonstrates robust antioxidant and anti-inflammatory properties intricately linked to the modulation of mitochondrial function. However, the specific protective impact of ISO on SAP remains to be fully elucidated. In this study, we demonstrated that ISO treatment significantly alleviated pancreatic damage and reduced serum lipase and amylase levels in the mouse model of SAP induced by sodium taurocholate (STC) or L-arginine. Utilizing an in vitro SAP cell model, we found that ISO co-administration markedly prevented STC-induced pancreatic acinar cell necrosis, primarily by inhibiting mitochondrial ROS generation, preserving ATP production, maintaining mitochondrial membrane potential, and preventing the oxidative damage and release of mitochondrial DNA. Mechanistically, our investigation identified that high-temperature requirement A2 (HtrA2) may play a central regulatory role in mediating the protective effect of ISO on mitochondrial dysfunction in STC-injured acinar cells. Furthermore, through an integrated approach involving bioinformatics analysis, molecular docking analysis, and experimental validation, we uncovered that ISO may directly impede the histone demethylation activity of KDM5B, leading to the restoration of pancreatic HtrA2 expression and thereby preserving mitochondrial function in pancreatic acinar cells following STC treatment. In conclusion, this study not only sheds new light on the intricate molecular complexities associated with mitochondrial dysfunction during the progression of SAP but also underscores the promising value of ISO as a natural therapeutic option for SAP.

Photoinduced Pd-Catalyzed Enantioselective Carboamination of Dienes via Aliphatic C-H Bond Elaboration.

Three-component diene carboaminations offer a potent means to access synthetically valuable allylic amines with rapid molecular complexity escalation. The existing literature primarily discloses racemic examples, necessitating the use of halides/pseudohalides as substrates. This paper introduces a photoinduced Pd-catalyzed enantioselective three-component carboamination of aryl-substituted 1,3-dienes, leveraging aliphatic C-H bonds for rapid synthesis. The reaction employs 10 mol % of chiral palladium catalyst and an excess aryl bromide as the HAT reagent. This approach yields diverse chiral allylamines with moderate to excellent enantioselectivities. Notably, it stands as the first instance of an asymmetric three-component diene carboamination reaction, directly utilizing abundant C(sp3)-H bearing partners, such as toluene-type substrates, ethers, amines, esters, and ketones. The protocol exhibits versatility across amines, encompassing aliphatic, aromatic, primary, and secondary derivatives. This method could serve as a versatile platform for stereoselective incorporation of various nucleophiles, dienes, and C(sp3)-H bearing partners.

Qingkailing granule alleviates pulmonary fibrosis by inhibiting PI3K/AKT and SRC/STAT3 signaling pathways.

Pulmonary fibrosis (PF) poses a significant challenge with limited treatment options and a high mortality rate of approximately 45 %. Qingkailing Granule (QKL), derived from the Angong Niuhuang Pill, shows promise in addressing pulmonary conditions. Using a comprehensive approach, combining network pharmacology analysis with experimental validation, this study explores the therapeutic effects and mechanisms of QKL against PF for the first time. In vivo, QKL reduced collagen deposition and suppressed proinflammatory cytokines in a bleomycin-induced PF mouse model. In vitro studies demonstrated QKL's efficacy in protecting cells from bleomycin-induced injury and reducing collagen accumulation and cell migration in TGF-ß1-induced pulmonary fibrosis cell models. Network pharmacology analysis revealed potential mechanisms, confirmed by western blotting, involving the modulation of PI3K/AKT and SRC/STAT3 signaling pathways. Molecular docking simulations highlighted interactions between QKL's active compounds and key proteins, showing inhibitory effects on epithelial damage and fibrosis. Collectively, these findings underscore the therapeutic potential of QKL in alleviating pulmonary inflammation and fibrosis through the downregulation of PI3K/AKT and SRC/STAT3 signaling pathways, with a pivotal role attributed to its active compounds.

3D facial mask for facial asymmetry diagnosis.

Objectives: Facial asymmetry is a common problem seen in orthodontic clinics that may affect patient esthetics. In some instances, severe asymmetry that affects patient esthetics may cause psychological issues. An objective method is therefore required to help orthodontists identify asymmetry issues. Materials and methods: We used three-dimensional (3D) facial images and landmark-based anthropometric analysis to construct a 3D facial mask to evaluate asymmetry. The landmark coordinates were transformed using a symmetric 3D face model to evaluate the efficacy of this method. Patients with facial asymmetry were recruited to conduct mirror and overlap analysis to form color maps, which were used to verify the utility of the novel soft tissue landmark-based method. Results: The preliminary results demonstrated that the asymmetry evaluation method had a similar response rate compared to diagnosis using mirror and overlap 3D images, and could therefore identify 3D asymmetry problems. Conclusions: By using 3D facial scans and 3D anthropometric analysis, we developed a preliminary evaluation method that provides objective parameters to clinically evaluate patient facial asymmetry and aid in the diagnosis of asymmetric areas. Clinical relevance: This study presents a novel facial asymmetry diagnostic method that has the potential to aid clinical decisions during problem identification, treatment planning, and efficacy evaluation.

Elucidating the distinctive regulatory effects and mechanisms of active compounds in Salvia miltiorrhiza Bunge via network pharmacology: Unveiling their roles in the modulation of platelet activation and thrombus formation.

Salvia miltiorrhiza Bunge. (DS), as an important traditional Chinese medicine (TCM), has a long history of usage for promoting blood circulation and removing blood stasis. Modern studies have shown that the chemical components of DS have many biological activities such as cardiovascular protection, anti-arrhythmia, anti-atherosclerosis, improvement of microcirculation, protection of myocardium, inhibition and removal of platelet aggregation. Nevertheless, the action mechanism of DS as well its active compounds on platelet activation has not been fully uncovered. This study aimed to find out the potential targets and mechanisms of DS in the modulation of platelet activation and thrombosis, using network pharmacology and biological experimental. These compounds with anti-thrombotic activity in DS, cryptotanshinone (CPT), isoeugenol (ISO) and tanshinone IIA (TSA), together with the corresponding targets being Src, Akt and RhoA are screened by network pharmacology. We confirmed that ISO, CPT and TSA dose-dependently inhibited platelet activation in vitro, mainly by inhibiting agonist-induced clot retraction, aggregation and P-selectin and ATP release. The western blot findings indicated that ISO, CPT, and TSA led to reduced levels of p-Akt and p-ERK in activated platelets. Additionally, ISO and TSA were observed to decrease p-cSrc expression while increasing RhoA expression. ISO, CPT, and TSA demonstrated a potential to restrict the advancement of carotid arterial thrombosis in vivo. We confirm that ISO, CPT and TSA are the key anti-thrombotic active compounds in DS. These active compounds exhibit unique inhibitory effects on platelet activation and thrombus formation by modulating the Akt/ERK and cSrc/RhoA signaling pathways.

Structural and functional basis of low-affinity SAM/SAH-binding in the conserved MTase of the multi-segmented Alongshan virus distantly related to canonical unsegmented flaviviruses.

Alongshan virus (ALSV), a newly discovered member of unclassified Flaviviridae family, is able to infect humans. ALSV has a multi-segmented genome organization and is evolutionarily distant from canonical mono-segmented flaviviruses. The virus-encoded methyltransferase (MTase) plays an important role in viral replication. Here we show that ALSV MTase readily binds S-adenosyl-L-methionine (SAM) and S-adenosyl-L-homocysteine (SAH) but exhibits significantly lower affinities than canonical flaviviral MTases. Structures of ALSV MTase in the free and SAM/SAH-bound forms reveal that the viral enzyme possesses a unique loop-element lining side-wall of the SAM/SAH-binding pocket. While the equivalent loop in flaviviral MTases half-covers SAM/SAH, contributing multiple hydrogen-bond interactions; the pocket-lining loop of ALSV MTase is of short-length and high-flexibility, devoid of any physical contacts with SAM/SAH. Subsequent mutagenesis data further corroborate such structural difference affecting SAM/SAH-binding. Finally, we also report the structure of ALSV MTase bound with sinefungin, an SAM-analogue MTase inhibitor. These data have delineated the basis for the low-affinity interaction between ALSV MTase and SAM/SAH and should inform on antiviral drug design.

Calcium/P53/Ninjurin 1 Signaling Mediates Plasma Membrane Rupture of Acinar Cells in Severe Acute Pancreatitis.

Ninjurin 1 (NINJ1) is a double-transmembrane cell-surface protein that might mediate plasma membrane rupture (PMR) and the diffusion of inflammatory factors. PMR is a characteristic of acinar cell injury in severe acute pancreatitis (SAP). However, the involvement of NINJ1 in mediating the PMR of acinar cells in SAP is currently unclear. Our study has shown that NINJ1 is expressed in acinar cells, and the expression is significantly upregulated in sodium-taurocholate-induced SAP. The knockout of NINJ1 delays PMR in acinar cells and alleviates SAP. Moreover, we observed that NINJ1 expression is mediated by Ca2+ concentration in acinar cells. Importantly, we found that Ca2+ overload drives mitochondrial stress to upregulate the P53/NINJ1 pathway, inducing PMR in acinar cells, and amlodipine, a Ca2+ channel inhibitor, can reduce the occurrence of PMR by decreasing the concentration of Ca2+. Our results demonstrate the mechanism by which NINJ1 induces PMR in SAP acinar cells and provide a potential new target for treatment of SAP.

NINJ1 Regulates Platelet Activation and PANoptosis in Septic Disseminated Intravascular Coagulation.

Disseminated intravascular coagulation (DIC), which is closely related to platelet activation, is a key factor leading to high mortality in sepsis. The release of contents from plasma membrane rupture after platelet death further aggravates thrombosis. Nerve injury-induced protein 1 (NINJ1) is a cell membrane protein that mediates membrane disruption, a typical marker of cell death, through oligomerization. Nevertheless, whether NINJ1 is expressed in platelets and regulates the platelet function remains unclear. The aim of this study was to evaluate the expression of NINJ1 in human and murine platelets and elucidate the role of NINJ1 in platelets and septic DIC. In this study, NINJ1 blocking peptide (NINJ126-37) was used to verify the effect of NINJ1 on platelets in vitro and in vivo. Platelet αIIbß3 and P-selectin were detected by flow cytometry. Platelet aggregation was measured by turbidimetry. Platelet adhesion, spreading and NINJ1 oligomerization were examined by immunofluorescence. Cecal perforation-induced sepsis and FeCl3-induced thrombosis models were used to evaluate the role of NINJ1 in platelet, thrombus and DIC in vivo. We found that inhibition of NINJ1 alleviates platelet activation in vitro. The oligomerization of NINJ1 is verified in membrane-broken platelets, which is regulated by the PANoptosis pathway. In vivo studies demonstrate that inhibition of NINJ1 effectively reduces platelet activation and membrane disruption, thus suppressing platelet-cascade reaction and leading to anti-thrombosis and anti-DIC in sepsis. These data demonstrate that NINJ1 is critical in platelet activation and plasma membrane disruption, and inhibition of NINJ1 effectively reduces platelet-dependent thrombosis and DIC in sepsis. This is the first study to reveal the key role of NINJ1 in platelet and its related disorders.

A Potent Neutralizing Nanobody Targeting the Spike Receptor-Binding Domain of SARS-CoV-2 and the Structural Basis of Its Intimate Binding.

The continuous spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) around the world has raised unprecedented challenges to the human society. Antibodies and nanobodies possessing neutralization activity represent promising drug candidates. In this study, we report the identification and characterization of a potent SARS-CoV-2 neutralizing nanobody that targets the viral spike receptor-binding domain (S-RBD). The nanobody, termed as Nb-007, engages SARS-CoV-2 S-RBD with the two-digit picomolar binding affinity and shows outstanding virus entry-inhibition activity. The complex structure of Nb-007 bound to SARS-CoV-2 S-RBD reveals an epitope that is partially overlapping with the binding site for the human receptor of angiotensin-converting enzyme 2 (ACE2). The nanobody therefore exerts neutralization by competing with ACE2 for S-RBD binding, which is further ascertained by our in-vitro biochemical analyses. Finally, we also show that Nb-007 reserves promising, though compromised, neutralization activity against the currently-circulating Delta variant and that fusion of the nanobody with Fc dramatically increases its entry-inhibition capacity. Taken together, these data have paved the way of developing Nb-007 as a drug-reserve for potential treatment of SARS-CoV-2 related diseases.

An engineered 5-helix bundle derived from SARS-CoV-2 S2 pre-binds sarbecoviral spike at both serological- and endosomal-pH to inhibit virus entry.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and related sarbecoviruses enter host cells by receptor-recognition and membrane-fusion. An indispensable step in fusion is the formation of 6-helix bundle by viral spike heptad repeats 1 and 2 (HR1 and HR2). Here, we report the construction of 5-helix bundle (5HB) proteins for virus infection inhibition. The optimal construct inhibits SARS-CoV-2 pseudovirus entry with sub-micromolar IC50. Unlike HR2-based peptides that cannot bind spike in the pre-fusion conformation, 5HB features with the capability of binding to pre-fusion spike. Furthermore, 5HB binds viral HR2 at both serological- and endosomal-pH, highlighting its entry-inhibition capacity when SARS-CoV-2 enters via either cell membrane fusion or endosomal route. Finally, we show that 5HB could neutralize S-mediated entry of the predominant SARS-CoV-2 variants and a wide spectrum of sarbecoviruses. These data provide proof-of-concept evidence that 5HB might be developed for the prevention and treatment of SARS-CoV-2 and other emerging sarbecovirus infections.

S19W, T27W, and N330Y mutations in ACE2 enhance SARS-CoV-2 S-RBD binding toward both wild-type and antibody-resistant viruses and its molecular basis.

SARS-CoV-2 recognizes, via its spike receptor-binding domain (S-RBD), human angiotensin-converting enzyme 2 (ACE2) to initiate infection. Ecto-domain protein of ACE2 can therefore function as a decoy. Here we show that mutations of S19W, T27W, and N330Y in ACE2 could individually enhance SARS-CoV-2 S-RBD binding. Y330 could be synergistically combined with either W19 or W27, whereas W19 and W27 are mutually unbeneficial. The structures of SARS-CoV-2 S-RBD bound to the ACE2 mutants reveal that the enhanced binding is mainly contributed by the van der Waals interactions mediated by the aromatic side-chains from W19, W27, and Y330. While Y330 and W19/W27 are distantly located and devoid of any steric interference, W19 and W27 are shown to orient their side-chains toward each other and to cause steric conflicts, explaining their incompatibility. Finally, using pseudotyped SARS-CoV-2 viruses, we demonstrate that these residue substitutions are associated with dramatically improved entry-inhibition efficacy toward both wild-type and antibody-resistant viruses. Taken together, our biochemical and structural data have delineated the basis for the elevated S-RBD binding associated with S19W, T27W, and N330Y mutations in ACE2, paving the way for potential application of these mutants in clinical treatment of COVID-19.

Crystal structure of SARS-CoV-2 nsp10 bound to nsp14-ExoN domain reveals an exoribonuclease with both structural and functional integrity.

The emergence of SARS-CoV-2 infection has posed unprecedented threat to global public health. The virus-encoded non-structural protein 14 (nsp14) is a bi-functional enzyme consisting of an exoribonuclease (ExoN) domain and a methyltransferase (MTase) domain and plays a pivotal role in viral replication. Here, we report the structure of SARS-CoV-2 nsp14-ExoN domain bound to its co-factor nsp10 and show that, compared to the SARS-CoV nsp10/nsp14-full-length complex, SARS-CoV-2 nsp14-ExoN retains an integral exoribonuclease fold and preserves an active configuration in the catalytic center. Analysis of the nsp10/nsp14-ExoN interface reveals a footprint in nsp10 extensively overlapping with that observed in the nsp10/nsp16 structure. A marked difference in the co-factor when engaging nsp14 and nsp16 lies in helix-α1', which is further experimentally ascertained to be involved in nsp14-binding but not in nsp16-engagement. Finally, we also show that nsp10/nsp14-ExoN is enzymatically active despite the absence of nsp14-MTase domain. These data demonstrate that SARS-CoV-2 nsp10/nsp14-ExoN functions as an exoribonuclease with both structural and functional integrity.

Chiral-Anion-Mediated Asymmetric Heck-Matsuda Reaction of Acyclic Alkenyl Alcohols.

Acyclic internal alkenes are a class of challenging substrates in asymmetric Heck-type reactions due to difficulties related to both reactivity and selectivity control. Employing acyclic alkenyl alcohols, an asymmetric Heck-Matsuda reaction is developed through the strategy of chiral anion phase transfer. Various chiral ketones could be obtained in high levels of enantioselectivity. A catalytic amount of dimethyl sulfoxide (DMSO) as an additive is crucial for the reaction to suppress the palladium-hydride-mediated side reactions.

Crystal structure of bovine herpesvirus 1 glycoprotein D bound to nectin-1 reveals the basis for its low-affinity binding to the receptor.

Bovine herpesvirus 1 (BHV-1) has received increasing attention for its potential oncolytic applications. BHV-1 recognizes nectin-1 for cell entry via viral glycoprotein D (gD) but represents a low-affinity nectin-1 binding virus. The molecular basis underlying this low receptor-binding affinity, however, remains unknown. Here, the crystal structures of BHV-1 gD in the free and nectin-1-bound forms are presented. While showing an overall resembled nectin-1 binding mode to other alphaherpesvirus gDs, BHV-1 gD has a unique G-strand/α2-helix interloop that disturbs gD/nectin-1 interactions. Residue R188 residing in this loop is observed to otherwise cause strong steric hindrance with the bound receptor, making a large conformational change of the loop a prerequisite for nectin-1 engagement. Subsequently, substitution of R188 with glycine markedly enhances the affinity of the BHV-1-gD/nectin-1 interaction (by about fivefold). These structural and functional data delineate the receptor-recognition basis for BHV-1, which might facilitate BHV-1-based oncolytic design in the future.