Abrus precatorius Leaf Extract Stimulates Insulin-mediated Muscle Glucose Uptake: In vitro Studies and Phytochemical Analysis

Diabetes mellitus, linked with insulin resistance and hyperglycaemia, is a leading cause of mortality. Glucose uptake through glucose transporter type 4, especially in skeletal muscle, is crucial for maintaining euglycaemia and is a key pathway targeted by antidiabetic medication. Abrus precatorius is a medicinal plant with demonstrated antihyperglycaemic activity in animal models, but its mechanisms are unclear.This study evaluated the effect of a 50% ethanolic (v/v) A. precatorius leaf extract on (1) insulin-stimulated glucose uptake and (2) related gene expression in differentiated C2C12 myotubes using rosiglitazone as a positive control, and (3) generated a comprehensive phytochemical profile of A. precatorius leaf extract using liquid chromatography-high resolution mass spectrometry to elucidate its antidiabetic compounds. A. precatorius leaf extract significantly increased insulin-stimulated glucose uptake, and insulin receptor substrate 1 and Akt substrate of 160 kDa gene expression; however, it had no effect on glucose transporter type 4 gene expression. At 250 µg/mL A. precatorius leaf extract, the increase in glucose uptake was significantly higher than 1 µM rosiglitazone. Fifty-five phytochemicals (primarily polyphenols, triterpenoids, saponins, and alkaloids) were putatively identified, including 24 that have not previously been reported from A. precatorius leaves. Abrusin, precatorin I, glycyrrhizin, hemiphloin, isohemiphloin, hispidulin 4'-O-β-D-glucopyranoside, homoplantaginin, and cirsimaritin were putatively identified as known major compounds previously reported from A. precatorius leaf extract. A. precatorius leaves contain antidiabetic phytochemicals and enhance insulin-stimulated glucose uptake in myotubes via the protein kinase B/phosphoinositide 3-kinase pathway by regulating insulin receptor substrate 1 and Akt substrate of 160 kDa gene expression. Therefore, A. precatorius leaves may improve skeletal muscle insulin sensitivity and hyperglycaemia. Additionally, it is a valuable source of bioactive phytochemicals with potential therapeutic use for diabetes.

Unsupervised and supervised AI on molecular dynamics simulations reveals complex characteristics of HLA-A2-peptide immunogenicity

Immunologic recognition of peptide antigens bound to class I major histocompatibility complex (MHC) molecules is essential to both novel immunotherapeutic development and human health at large. Current methods for predicting antigen peptide immunogenicity rely primarily on simple sequence representations, which allow for some understanding of immunogenic features but provide inadequate consideration of the full scale of molecular mechanisms tied to peptide recognition. We here characterize contributions that unsupervised and supervised artificial intelligence (AI) methods can make toward understanding and predicting MHC(HLA-A2)-peptide complex immunogenicity when applied to large ensembles of molecular dynamics simulations. We first show that an unsupervised AI method allows us to identify subtle features that drive immunogenicity differences between a cancer neoantigen and its wild-type peptide counterpart. Next, we demonstrate that a supervised AI method for class I MHC(HLA-A2)-peptide complex classification significantly outperforms a sequence model on small datasets corrected for trivial sequence correlations. Furthermore, we show that both unsupervised and supervised approaches reveal determinants of immunogenicity based on time-dependent molecular fluctuations and anchor position dynamics outside the MHC binding groove. We discuss implications of these structural and dynamic immunogenicity correlates for the induction of T cell responses and therapeutic T cell receptor design.

Thermal degradation and flame spread characteristics of epoxy polymer composites incorporating mycelium

Although bioderived flame retardants are environmentally sustainable and less toxic, their impact on the thermal stability and flammability of polymers remains poorly understood. In this study, we assessed the influence of mycelium on the thermal stability and flame spread characteristics of epoxy through thermogravimetric analysis, Fourier transform infrared spectroscopy, the UL94 flammability test, and scanning electron microscopy. We observed a decrease in the maximum mass loss rate temperature when mycelium was incorporated into epoxy, indicating an earlier onset of thermal degradation. The inclusion of mycelium increased char yields above 418 °C due to mycelium's inherent char-forming ability. However, mycelium did not alter the thermal degradation pathway of epoxy. Furthermore, according to the UL94 test results, the incorporation of mycelium reduced the flame spread rate compared to that of neat epoxy. These findings contribute to our understanding of the interaction between bioderived flame retardants and polymers paving the way for the development of more sustainable fireproofing materials.

The nematode parasite Steinernema hermaphroditum is pathogenic to Drosophila melanogaster larvae without activating their immune response

Entomopathogenic nematodes are commonly used to control insect pest populations in the field. They also contribute substantially to understanding the molecular basis of nematode pathogenicity and insect anti-nematode immunity. Here, we tested the effect of the entomopathogenic nematode Steinernema hermaphroditum on the survival and immune signaling regulation of Drosophila melanogaster wild type larvae. Our results indicate that S. hermaphroditum infective juveniles are pathogenic toward D. melanogaster larvae, but they fail to activate certain immune pathway readout genes. These findings imply that S. hermaphroditum employs mechanisms that allow these parasitic nematodes to interfere with the D. melanogaster immune system.

Molecular basis of differential HLA class I-restricted T cell recognition of a highly networked HIV peptide

Cytotoxic-T-lymphocyte (CTL) mediated control of HIV-1 is enhanced by targeting highly networked epitopes in complex with human-leukocyte-antigen-class-I (HLA-I). However, the extent to which the presenting HLA allele contributes to this process is unknown. Here we examine the CTL response to QW9, a highly networked epitope presented by the disease-protective HLA-B57 and disease-neutral HLA-B53. Despite robust targeting of QW9 in persons expressing either allele, T cell receptor (TCR) cross-recognition of the naturally occurring variant QW9_S3T is consistently reduced when presented by HLA-B53 but not by HLA-B57. Crystal structures show substantial conformational changes from QW9-HLA to QW9_S3T-HLA by both alleles. The TCR-QW9-B53 ternary complex structure manifests how the QW9-B53 can elicit effective CTLs and suggests sterically hindered cross-recognition by QW9_S3T-B53. We observe populations of cross-reactive TCRs for B57, but not B53 and also find greater peptide-HLA stability for B57 in comparison to B53. These data demonstrate differential impacts of HLAs on TCR cross-recognition and antigen presentation of a naturally arising variant, with important implications for vaccine design.

Momordica cochinchinensis (Gấc) Seed Extracts Induce Apoptosis and Necrosis in Melanoma Cells

Momordica cochinchinensis is a herbal medicine used throughout Asia and this study investigated the antimelanoma potentials and molecular mechanisms of M. cochinchinensis seed with emphasis on extraction to optimise bioactivity. Overall, the aqueous extract was superior, with a wider diversity and higher concentration of proteins and peptides that was more cytotoxic to the melanoma cells than other extraction solvents. The IC50 of the aqueous extract on melanoma cells were similar to treatment with current anticancer drugs, vemurafenib and cisplatin. This cytotoxicity was cancer-specific with lower cytotoxic effects on HaCaT epidermal keratinocytes. Cytotoxicity correlated with MAPK signalling pathways leading to apoptosis and necrosis induced by triggering tumour necrosis factor receptor-1 (TNFR1), reducing the expression of nuclear factor kappa B (NF-kB), and suppression of BRAF/MEK. This efficacy of M. cochinchinensis seed extracts on melanoma cells provides a platform for future clinical trials as potent adjunctive therapy for metastatic melanoma.

On the Choice of Active Site Sequences for Kinase-Ligand Affinity Prediction

Recent work showed that active site rather than full-protein-sequence information improves predictive performance in kinase-ligand binding affinity prediction. To refine the notion of an “active site”, we here propose and compare multiple definitions. We report significant evidence that our novel definition is superior to previous definitions and better models of ATP-noncompetitive inhibitors. Moreover, we leverage the discontiguity of the active site sequence to motivate novel protein-sequence augmentation strategies and find that combining them further improves performance.

Mapping the human gut mycobiome in middle-aged and elderly adults: multiomics insights and implications for host metabolic health

OBJECTIVE

The human gut fungal community, known as the mycobiome, plays a fundamental role in the gut ecosystem and health. Here we aimed to investigate the determinants and long-term stability of gut mycobiome among middle-aged and elderly adults. We further explored the interplay between gut fungi and bacteria on metabolic health.

DESIGN

The present study included 1244 participants from the Guangzhou Nutrition and Health Study. We characterised the long-term stability and determinants of the human gut mycobiome, especially long-term habitual dietary consumption. The comprehensive multiomics analyses were performed to investigate the ecological links between gut bacteria, fungi and faecal metabolome. Finally, we examined whether the interaction between gut bacteria and fungi could modulate the metabolic risk.

RESULTS

The gut fungal composition was temporally stable and mainly determined by age, long-term habitual diet and host physiological states. Specifically, compared with middle-aged individuals, Blastobotrys and Agaricomycetes spp were depleted, while Malassezia was enriched in the elderly. Dairy consumption was positively associated with Saccharomyces but inversely associated with Candida. Notably, Saccharomycetales spp interacted with gut bacterial diversity to influence insulin resistance. Bidirectional mediation analyses indicated that bacterial function or faecal histidine might causally mediate an impact of Pichia on blood cholesterol.

CONCLUSION

We depict the sociodemographic and dietary determinants of human gut mycobiome in middle-aged and elderly individuals, and further reveal that the gut mycobiome may be closely associated with the host metabolic health through regulating gut bacterial functions and metabolites.

MINI-BAERMANN FUNNEL, A SIMPLE DEVICE FOR CLEANING NEMATODE INFECTIVE LARVAE

The Baermann filter method is a long-standing, simple technique for recovering nematodes from soil and charcoal coprocultures. Material containing the nematodes is placed on a mesh screen lined with several layers of tissue paper or cheesecloth, and the screen is placed in the mouth of the funnel. Rubber tubing attached to the funnel stem is clamped, and water is added to submerge the material. The filtration material allows the nematodes to swim through while holding back the substrate. Over time the nematodes settle at the clamp in the tubing. After several hours, the clamp is opened and water containing the nematodes is collected. Although recovery of the nematodes is efficient, they are often contaminated with soil or charcoal debris, requiring a secondary cleaning by sedimentation or filtration. Described here is a small, simplified version of the Baermann apparatus that can be used as a secondary cleaning device. The "mini-Baermann" is constructed from materials commonly found in the laboratory. Experiments using infective larvae of 3 nematode species demonstrated that the majority of the larvae applied to the device are collected within 2 hr, and nearly all by 4 hr. Dead larvae fail to pass through the filter and do not significantly impact the passage of living larvae. In addition to removing debris from nematode suspensions, this device can rapidly and efficiently separate living, motile larvae from dead larvae.

Insights into SARS-CoV-2's Mutations for Evading Human Antibodies: Sacrifice and Survival

The highly infectious SARS-CoV-2 variant B.1.351 that first emerged in South Africa with triple mutations (N501Y, K417N, and E484K) is globally worrisome. It is known that N501Y and E484K can enhance binding between the coronavirus receptor domain (RBD) and human ACE2. However, the K417N mutation appears to be unfavorable as it removes one interfacial salt bridge. Here, we show that despite the decrease in binding affinity (1.48 kcal/mol) between RBD and ACE2, the K417N mutation abolishes a buried interfacial salt bridge between the RBD and neutralizing antibody CB6. This substantially reduces their binding energy by 9.59 kcal/mol, thus facilitating the process by which the variant efficiently eludes CB6 (including many other antibodies). Our theoretical predictions agree with existing experimental findings. Harnessing the revealed molecular mechanisms makes it possible to redesign therapeutic antibodies, thus making them more efficacious.

Measuring the arterial phase of the right coronary artery in the patients suspected of coronary artery disease: a dual study by dynamic angiography and deep learning program

Funding Acknowledgements

Type of funding sources: None.

Background. In the diagnosis of coronary artery disease (CAD), coronary angiography (CA) plays a crucial role in determining the location and severity of the stenosis, the anatomical aspect of a lesion. It does not accurately reflect the flow dynamics in the coronary artery. This study aimed to evaluate the coronary flow abnormalities based on our new angiographic technique and Deep Learning (DL) program in patients suspected of CAD.

Methods. We randomly selected patients who were admitted with suspected CAD. All patients underwent our new technique of CA. After the index coronary artery was filled completely with contrast, we stopped the injection. At that time, the blood in white color flew in. The flow characteristics, the shape of the tip, borders, and direction could be clearly observed above a black background of the contrast. In this study, we measured the arterial phase (AP) from the beginning when the blood moved in until the end when all contrasts in black color washed out of the distal vasculature. In the DL protocol, the U-Net model combined with Dense-Net-121 and a binary image classification model are used to predict the beginning and ending frame. To obtain the best image for the DL program, we analyzed only the flow of the right coronary artery (RCA).

Results. 81 patients were enrolled. In patients with normal coronary angiography, the mean AP was 1.86s (27.4 +/- 5.4 frames). In patients with one significant lesion, the mean AP value was 2.35s (35.3 +/- 7.7 frames). The mean difference of the AP between the two groups was 0.49s (95% confidence interval: 0.295 to 0.694). This difference is statistically significant. Our DL has the mean root square error in predicting the AP was 0.34s.

Conclusion. In patients with CAD, the prolonged arterial phase could be accurately estimated using the DL program, reflecting the slow circulation of highly oxygenated blood. It could be used as a marker of coronary perfusion in future studies.

Anatomy of Spinal Venous Drainage for the Neurointerventionalist: From Puncture Site to Intervertebral Foramen

CSF-venous fistula is a relatively novel entity that is increasingly being recognized as a cause for spontaneous intracranial hypotension. Recently, our group published the first series of transvenous embolization of CSF-venous fistulas in this journal. Having now performed the procedure in 60 patients, we have garnered increasing familiarity with the anatomy and how to navigate our way through the venous system to any intervertebral foramen in the cervical, thoracic, and lumbar spine. The first part of this review summarizes the organization of spinal venous drainage as described in classic anatomy and interventional radiology texts, the same works that we studied when attempting our first cases. In the second part, we draw mostly on our own experience to provide a practical roadmap from the puncture site to the foramen. On the basis of these 2 parts, we hope this article will serve to collate the relevant anatomic knowledge and give confidence to colleagues who wish to embark on transvenous spinal procedures.

Enhanced Antimicrobial Activity and Low Phytotoxicity of Acoustically Synthesized Large Aspect Ratio Cu-BTC Metal-Organic Frameworks with Exposed Metal Sites

Metal-organic frameworks (MOFs) have recently been shown to be effective antimicrobial agents, particularly if they comprise pathogenicidal metal ions. Nevertheless, the accessibility of these active metal sites to the pathogen, and hence the MOFs' antimicrobial activity itself, is often poor since the metal nodes are usually embedded deep within its three-dimensional (3D) structure. We show that a unique copper-based (copper(II)-benzene-1,3,5-tricarboxylate) MOF, whose quasi-two-dimensional (quasi-2D) swordlike structure facilitates exposure of the metal ions along its surface, exhibits enhanced antimicrobial properties against three representative plant pathogens: a bacterium (Pseudomonas syringae), a fungus (Fusarium solani), and a virus (Odontoglossum ringspot virus (ORSV)). Such superior antimicrobial activity results in low minimum inhibitory concentrations (MICs)─half that of a commercial pesticide and an eighth of its conventional 3D cubic MOF counterpart (HKUST-1)─and hence low phytotoxicity, which can be attributed to the accessibility of the surface copper sites to the pathogen, thereby facilitating their adhesion and physical contact with the MOF. Additionally, we observed that orchids treated with the quasi-2D MOF showed negligible phytotoxicity and 80% decreased viral load. This work constitutes the first study to demonstrate the antimicrobial properties of this novel MOF against bacterial, fungal, and viral plant pathogens, and the first chemical control of ORSV.

Active Site Sequence Representations of Human Kinases Outperform Full Sequence Representations for Affinity Prediction and Inhibitor Generation: 3D Effects in a 1D Model

Recent advances in deep learning have enabled the development of large-scale multimodal models for virtual screening and de novo molecular design. The human kinome with its abundant sequence and inhibitor data presents an attractive opportunity to develop proteochemometric models that exploit the size and internal diversity of this family of targets. Here, we challenge a standard practice in sequence-based affinity prediction models: instead of leveraging the full primary structure of proteins, each target is represented by a sequence of 29 discontiguous residues defining the ATP binding site. In kinase-ligand binding affinity prediction, our results show that the reduced active site sequence representation is not only computationally more efficient but consistently yields significantly higher performance than the full primary structure. This trend persists across different models, data sets, and performance metrics and holds true when predicting pIC₅₀ for both unseen ligands and kinases. Our interpretability analysis reveals a potential explanation for the superiority of the active site models: whereas only mild statistical effects about the extraction of three-dimensional (3D) interaction sites take place in the full sequence models, the active site models are equipped with an implicit but strong inductive bias about the 3D structure stemming from the discontiguity of the active sites. Moreover, in direct comparisons, our models perform similarly or better than previous state-of-the-art approaches in affinity prediction. We then investigate a de novo molecular design task and find that the active site provides benefits in the computational efficiency, but otherwise, both kinase representations yield similar optimized affinities (for both SMILES- and SELFIES-based molecular generators). Our work challenges the assumption that the full primary structure is indispensable for modeling human kinases.

Oral Commissure Lift: A Retrospective Analysis of Complication Rates and Overall Outcomes

BACKGROUND

Downward-turning oral commissures and sagging mouth corners can present an unfavorable impression. We introduced a new oral commissure lift procedure and investigated its effectiveness and complication rates.

METHODS

Patients who underwent oral commissure lift in the plastic surgery clinic between January 2010 and December 2017 were enrolled retrospectively. Pre-and postoperative photographs were evaluated to measure oral commissure angles and analyze surgical complications, including visible scarring, unnatural appearance, and asymmetry. Many patients underwent a oral commissure lift with a simultaneous facelift. To exclude potential bias, we compared angular changes between patients receiving both oral commissure lift and facelift, with those receiving only oral commissure lift. Moreover, oral commissure angles of patients only receiving facelift were also measured. Statistical significance was set at p < 0.05.

RESULTS

Oral commissure lift was performed in 51 patients. The mean ages and follow-up periods were 46.7 ± 11.9 years, and 25.2 ± 22.9 months, respectively. The preoperative mean angles of the right and left oral commissures measured - 3.1 ± 4.0° and - 3.4 ± 3.7°, respectively, and postoperative mean angles measured 3.6 ± 3.2° and 3.3 ± 3.5°, respectively. Postoperative changes in oral commissure angles were statistically significant (p < 0.05). The low complication rate included undercorrection in one patient, asymmetry in one patient, and visible scarring in three patients. We found no statistically significant differences in the studies excluding bias.

CONCLUSIONS

The new oral commissure lift procedure for correcting sagging oral commissures was simple, safe, and effective with a low complication rate.

LEVEL OF EVIDENCE IV

This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Structure-Function Analysis of Resistance to Bamlanivimab by SARS-CoV-2 Variants Kappa, Delta, and Lambda

The newly emerging Kappa, Delta, and Lambda SARS-CoV-2 variants are worrisome, characterized with the double mutations E484Q/L452R, T478K/L452R, and F490S/L452Q, respectively, in their receptor binding domains (RBDs) of the spike proteins. As revealed in crystal structures, most of these residues (e.g., 452 and 484 in RBDs) are not in direct contact with interfacial residues in the angiotensin-converting enzyme 2 (ACE2). This suggests that albeit there are some possibly nonlocal effects, these mutations might not significantly affect RBD's binding with ACE2, which is an important step for viral entry into host cells. Thus, without knowing the molecular mechanism, these successful mutations (from the point of view of SARS-CoV-2) may be hypothesized to evade human antibodies. Using all-atom molecular dynamics (MD) simulation, here, we show that the E484Q/L452R mutations significantly reduce the binding affinity between the RBD of the Kappa variant and the antibody LY-CoV555 (also named as Bamlanivimab), which was efficacious for neutralizing the wild-type SARS-CoV-2. To verify simulation results, we further carried out experiments with both pseudovirions- and live virus-based neutralization assays and demonstrated that LY-CoV555 completely lost neutralizing activity against the L452R/E484Q mutant. Similarly, we show that mutations in the Delta and Lambda variants can also destabilize the RBD's binding with LY-CoV555. With the revealed molecular mechanism on how these variants evade LY-CoV555, we expect that more specific therapeutic antibodies can be accordingly designed and/or a precise mixing of antibodies can be achieved as a cocktail treatment for patients infected with these variants.

Crystal-structures-guided design of fragment-based drugs for inhibiting the main protease of SARS-CoV-2

Since the beginning of the COVID‐19 pandemic, scientists across the globe are racing to find a cure for the highly contagious infectious disease caused by the SARS‐CoV‐2 virus. Despite many promising ongoing progress, there are currently no FDA approved drug to treat infected patients. Recently, the crowdsourcing of drug discovery for inhibiting the main protease (Mpro) of SARS‐CoV‐2 have yielded a plenty of drug fragments resolved inside the active site of Mpro via the crystallography method. Following the principle of fragment‐based drug design (FBDD), we are motivated to design a potent drug candidate (named B19) by merging three fragments JFM, U0P, and HWH. Through extensive all‐atom molecular dynamics simulation and molecular docking, we found that B19 among all designed ones is most stable inside the Mpro's active site and the binding free energy of B19 is comparable to or even a little better than that of a native protein ligand processed by Mpro. Our promising results suggest that B19 and its derivatives can potentially be efficacious drug candidates for COVID‐19.

Racial/ethnic differences in cardiovascular outcomes in a universal healthcare system: insights from the CARTaGENE cohort

Background

While prior studies have shown racial/ethnic differences in cardiovascular (CV) outcomes within private or mixed health care systems, it remains uncertain whether inequalities in cardiovascular outcomes exist between different races and ethnicities in universal health care contexts. We aimed to determine whether there are racial/ethnicity disparities in long-term CV outcomes within a single-payer universal health care system.

Methods

The CARTaGENE study is a population-based prospective cohort study with enrollment of 19,996 individuals between 40–69 years in 2009, in the province of Quebec, Canada. Participants residing in four large metropolitan areas were randomly chosen from the provincial health insurance registry by strata of age, sex, and postal codes. Follow-up was available up to 2016. For this analysis, we retained only participants without prior known CV disease. The primary composite endpoint was time to the first CV event or intervention (CV death, acute coronary syndrome, heart failure, coronary revascularization, ischemic stroke, or peripheral vascular event or revascularization). We used unadjusted and adjusted Cox proportional hazard models to evaluate the association of self-defined race/ethnicity with the primary endpoint.

Results

There were 17,802 eligible participants with a mean age of 51 years (52.5% females) with 111,312 person-years of follow-up (median follow-up of 6.6 years). South Asian (SA) participants had the highest prevalence of diabetes mellitus (29%) and hypertension (32%). After adjustment for age and sex, SA ethnicity was associated with a 95% relative increase in risk for CV events, while East/Southeast Asian (ESA) ethnicity was associated with a 42% relative decrease in risk for CV events compared to White participants. After further adjustment for socioeconomic status and CV risk factors, ESA ethnicity remained associated with a similar decreased CV risk. In contrast, the association of SA ethnicity with increased CV risk was attenuated after full adjustment for baseline characteristics (Table 1).

Conclusions

Racial/ethnic disparities in long-term CV outcomes are present in a single-payer universal healthcare setting. ESA ethnicity was associated with a lower risk of long-term CV outcomes. Future studies are needed to corroborate the reduced risk of long-term major CV events associated with ESA ethnicity. Understanding the reasons related to potential CV protection with ESA ethnicity could facilitate endeavors to reduce long-term CV outcomes in other races/ethnicities.

Funding Acknowledgement

Type of funding sources: Public hospital(s). Main funding source(s): McGill Health University Center

Enhanced binding of the N501Y-mutated SARS-CoV-2 spike protein to the human ACE2 receptor: insights from molecular dynamics simulations

Recently, severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) variants (B.1.1.7 and B.1351) have emerged harbouring mutations that make them highly contagious. The N501Y mutation within the receptor‐binding domain (RBD) of the spike protein of these SARS‐CoV‐2 variants may enhance binding to the human angiotensin‐converting enzyme 2 (hACE2). However, no molecular explanation for such an enhanced affinity has so far been provided. Here, using all‐atom molecular dynamics simulations, we show that Y501 in the mutated RBD can be well‐coordinated by Y41 and K353 in hACE2 through hydrophobic interactions, which may increase the overall binding affinity of the RBD for hACE2 by approximately 0.81 kcal·mol⁻¹. The binding dynamics revealed in our study may provide a working model to facilitate the design of more effective antibodies.

Structural and Morphological Analysis of Cellulose Pulp Produced from the Fractionation of Eucalyptus obliqua Sawdust Using γ-Valerolactone

Organic solvents offer promising methods for the fractionation of Eucalyptus obliqua lignocellulosic biomass. This study investigated the impact of γ-valerolactone (GVL) fractionation on the morphology of cellulose and its internal structure using scanning electron microscopy (SEM), nuclear magnetic resonance (NMR) and Fourier-transform infrared (FT-IR) spectroscopy. The solubilized lignin precipitated on the macrofibril surface as lignin spheres. GVL fractionation significantly increased the crystallinity of the recovered pulps from 0.29 for the sawdust to an average of 0.53 and a maximum of 0.66. The main states of cellulose that were susceptible to hydrolysis during the fractionation were amorphous and surface cellulose, both of which were reduced significantly, while paracrystalline and pure crystalline fractions in the pulp increased. It was concluded that GVL fractionation can produce a crystalline cellulose pulp of high quality suitable for further processing.

In silico Exploration of Inhibitors for SARS-CoV-2's Papain-Like Protease

Coronavirus disease 2019 (COVID-19) is an ongoing global pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), with very limited treatments so far. Demonstrated with good druggability, two major proteases of SARS-CoV-2, namely main protease (Mpro) and papain-like protease (PLpro) that are essential for viral maturation, have become the targets for many newly designed inhibitors. Unlike Mpro that has been heavily investigated, PLpro is not well-studied so far. Here, we carried out the in silico high-throughput screening of all FDA-approved drugs via the flexible docking simulation for potential inhibitors of PLpro and explored the molecular mechanism of binding between a known inhibitor rac5c and PLpro. Our results, from molecular dynamics simulation, show that the chances of drug repurposing for PLpro might be low. On the other hand, our long (about 450 ns) MD simulation confirms that rac5c can be bound stably inside the substrate-binding site of PLpro and unveils the molecular mechanism of binding for the rac5c-PLpro complex. The latter may help perform further structural optimization and design potent leads for inhibiting PLpro.

Screening natural product extracts for potential enzyme inhibitors: protocols, and the standardisation of the usage of blanks in α-amylase, α-glucosidase and lipase assays

BACKGROUND

Enzyme assays have widespread applications in drug discovery from plants to natural products. The appropriate use of blanks in enzyme assays is important for assay baseline-correction, and the correction of false signals associated with background matrix interferences. However, the blank-correction procedures reported in published literature are highly inconsistent. We investigated the influence of using different types of blanks on the final calculated activity/inhibition results for three enzymes of significance in diabetes and obesity; α-glucosidase, α-amylase, and lipase. This is the first study to examine how different blank-correcting methods affect enzyme assay results. Although assays targeting the above enzymes are common in the literature, there is a scarcity of detailed published protocols. Therefore, we have provided comprehensive, step-by-step protocols for α-glucosidase-, α-amylase- and lipase-inhibition assays that can be performed in 96-well format in a simple, fast, and resource-efficient manner with clear instructions for blank-correction and calculation of results.

RESULTS

In the three assays analysed here, using only a buffer blank underestimated the enzyme inhibitory potential of the test sample. In the absorbance-based α-glucosidase assay, enzyme inhibition was underestimated when a sample blank was omitted for the coloured plant extracts. Similarly, in the fluorescence-based α-amylase and lipase assays, enzyme inhibition was underestimated when a substrate blank was omitted. For all three assays, method six [Raw Data - (Substrate + Sample Blank)] enabled the correction of interferences due to the buffer, sample, and substrate without double-blanking, and eliminated the need to add substrate to each sample blank.

CONCLUSION

The choice of blanks and blank-correction methods contribute to the variability of assay results and the likelihood of underestimating the enzyme inhibitory potential of a test sample. This highlights the importance of standardising the use of blanks and the reporting of blank-correction procedures in published studies in order to ensure the accuracy and reproducibility of results, and avoid overlooked opportunities in drug discovery research due to inadvertent underestimation of enzyme inhibitory potential of test samples resulting from unsuitable blank-correction. Based on our assessments, we recommend method six [RD - (Su + SaB)] as a suitable method for blank-correction of raw data in enzyme assays.

Anticancer activity of Momordica cochinchinensis (red gac) aril and the impact of varietal diversity

Background

Momordica cochinchinensis (Cucurbitaceae) is a nutritionally and medicinally important fruit restricted to South East Asia with diverse morphological and genetic variations but there is limited information on its medicinal potential.

Methods

M. cochinchinensis aril from 44 different samples in Australia, Thailand and Vietnam were extracted using different solvents and tested for its anticancer potential. Anticancer activity of M. cochinchinensis aril on breast cancer (MCF7 and BT474) and melanoma (MM418C1 and D24) cells were compared to control fibroblasts (NHDF). The cytotoxicity of the cells following treatment with the aril extract was determined using CCK-8 assay. Biochemical and morphological changes were analysed using flow cytometry, confocal and transmission electron microscopy to determine the mechanism of cell death.

Results

The water extract from the aril of M. cochinchinensis elicited significantly higher cytotoxicity towards breast cancer and melanoma cells than the HAE extract. The IC₅₀ concentration for the crude water extract ranged from 0.49 to 0.73 mg/mL and induced both apoptotic and necrotic cell death in a dose- and time-dependant manner with typical biochemical and morphological characteristics. The greatest cytotoxicity was observed from Northern Vietnam samples which caused 70 and 50% melanoma and breast cancer cell death, respectively.

Conclusions

The water extract of M. cochinchinensis aril caused significant apoptosis and necrosis of breast cancer and melanoma cells, with varieties from Northern Vietnam possessing superior activity. This highlights the potential of this fruit in the development of novel anticancer agents against such tumours, with specific regions on where to collect the best variety and extraction solvent for optimum activity.

In Silico Antibody Mutagenesis for Optimizing Its Binding to Spike Protein of Severe Acute Respiratory Syndrome Coronavirus 2

Coronavirus disease 2019 (COVID-19) is an ongoing global pandemic, and there are currently no FDA-approved medicines for treatment or prevention. Inspired by promising outcomes for convalescent plasma treatment, the development of antibody drugs (biologics) to block SARS-CoV-2 infection has been the focus of drug discovery, along with tremendous efforts in repurposing small-molecule drugs. In the past several months, experimentally, many human neutralizing monoclonal antibodies (mAbs) were successfully extracted from plasma of recovered COVID-19 patients. Currently, several mAbs targeting the SARS-CoV-2's spike glycoprotein (S-protein) are in clinical trials. With known atomic structures of the mAb and S-protein complex, it becomes possible to investigate in silico the molecular mechanism of mAb's binding with S-protein and to design more potent mAbs through protein mutagenesis studies, complementary to existing experimental efforts. Leveraging today's superb computing power, we propose a fully automated in silico protocol for quickly identifying possible mutations in a mAb (e.g., CB6) to enhance its binding affinity for S-protein for the design of more efficacious therapeutic mAbs.

Targeting Proteases for Treating COVID-19

The unprecedented pandemic of coronavirus disease 2019 (COVID-19) demands effective treatment for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. The infection of SARS-CoV-2 critically depends on diverse viral or host proteases, which mediate viral entry, viral protein maturation, as well as the pathogenesis of the viral infection. Endogenous and exogenous agents targeting for proteases have been proved to be effective toward a variety of viral infections ranging from HIV to influenza virus, suggesting protease inhibitors as a promising antiviral treatment for COVID-19. In this Review, we discuss how host and viral proteases participated in the pathogenesis of COVID-19 as well as the prospects and ongoing clinical trials of protease inhibitors as treatments.

Structure-based lead optimization of herbal medicine rutin for inhibiting SARS-CoV-2's main protease

Coronavirus disease 2019 (COVID-19) is an ongoing global pandemic with very limited specific treatments. To fight COVID-19, various traditional antiviral medicines have been prescribed in China to infected patients with mild to moderate symptoms and received unexpected success in controlling the disease. However, the molecular mechanisms of how these herbal medicines interact with the SARS-CoV-2 virus that causes COVID-19 have remained elusive. It is well known that the main protease (Mpro) of SARS-CoV-2 plays an important role in maturation of many viral proteins such as the RNA-dependent RNA polymerase. Here, we explore the underlying molecular mechanisms of the computationally determined top candidate, namely, rutin which is a key component in many traditional antiviral medicines such as Lianhuaqinwen and Shuanghuanlian, for inhibiting the viral target-Mpro. Using in silico methods (docking and molecular dynamics simulations), we revealed the dynamics and energetics of rutin when interacting with the Mpro of SARS-CoV-2, suggesting that the highly hydrophilic rutin molecule can be bound inside the Mpro's pocket (active site) and possibly inhibit its biological functions. In addition, we optimized the structure of rutin and designed two more hydrophobic analogs, M1 and M2, which satisfy the rule of five for western medicines and demonstrated that they (M2 in particular) possess much stronger binding affinities to the SARS-COV-2s Mpro than rutin, due to the enhanced hydrophobic interaction as well as more hydrogen bonds. Therefore, our results provide invaluable insights into the mechanism of a ligand's binding inside the Mpro and shed light on future structure-based designs of high-potent inhibitors for SARS-CoV-2 Mpro.

Low-Dose X-ray-Responsive Diselenide Nanocarriers for Effective Delivery of Anticancer Agents

X-ray-responsive nanocarriers for anticancer drug delivery have shown great promise for enhancing the efficacy of chemoradiotherapy. A critical challenge remains for development of such radiation-controlled drug delivery systems (DDSs), which is to minimize the required X-ray dose for triggering the cargo release. Herein, we design and fabricate an effective DDS based on diselenide block copolymers (as nanocarrier), which can be triggered to release their cargo with a reduced radiation dose of 2 Gy due to their sensitivity to both X-ray and the high level of reactive oxygen species (ROS) in the microenvironment of cancer cells. The underlying molecular mechanism is further illustrated by proton nuclear magnetic resonance (¹H NMR) experiments and density functional theory (DFT) calculations. In vivo experiments on tumor-bearing mice validated that the loaded drugs are effectively delivered to the tumor site and exert remarkable antitumor effects (minimum tumor volume/weight) along with X-ray. Furthermore, the diselenide nanocarriers exhibit no noticeable cytotoxicity. These findings provide new insights for the de novo design of radiation-controlled DDSs for cancer chemoradiotherapy.

Exploring the Sequence Diversity of Cyclotides from Vietnamese Viola Species

Viola is the largest genus in the Violaceae plant family and is known for its ubiquitous natural production of cyclotides. Many Viola species are used as medicinal herbs across Asia and are often consumed by humans in teas for the treatment of diseases, including ulcers and asthma. Previous studies reported the isolation of cyclotides from Viola species in many countries in the hope of discovering novel compounds with anti-cancer activities; however, Viola species from Vietnam have not been investigated to date. Here, the discovery of cyclotides from three Viola species (V. arcuata, V. tonkinensis, and V. austrosinensis) collected in the northern mountainous region of Vietnam is reported. Ten cyclotides were isolated from these three Viola species: four are novel and six were previously reported to be expressed in other plants. The structures of three of the new bracelet cyclotides are similar to that of cycloviolacin O2. Because cycloviolacin O2 has previously been shown to have potent activity against a wide range of cancer cell lines including HeLa (human cervical cancer cells) and PC-3 (human prostate cancer cells), the cancer cytotoxicity of the cyclotides isolated from V. arcuata was assessed. All tested cyclotides were cytotoxic against cancer cells, albeit to varying degrees. The sequences discovered in this study significantly expand the understanding of cyclotide diversity, especially in comparison with other cyclotides found in plants from the Asian region.

In Silico Exploration of the Molecular Mechanism of Clinically Oriented Drugs for Possibly Inhibiting SARS-CoV-2's Main Protease

Currently, the new coronavirus disease 2019 (COVID-19) is a global pandemic without any well-calibrated treatment. To inactivate the SARS-CoV-2 virus that causes COVID-19, the main protease (Mpro) that performs key biological functions in the virus has been the focus of extensive studies. With the fast-response experimental efforts, the crystal structures of Mpro of the SARS-CoV-2 virus have just become available recently. Herein, we theoretically investigated the mechanism of binding between the Mpro's pocket and various marketed drug molecules being tested in clinics to fight COVID-19 that show promising outcomes. By combining the existing experimental results with our computational ones, we revealed an important ligand binding mechanism of the Mpro, demonstrating that the binding stability of a ligand inside the Mpro pocket can be significantly improved if part of the ligand occupies its so-called "anchor" site. Along with the highly potent drugs and/or molecules (such as nelfinavir) revealed in this study, the newly discovered binding mechanism paves the way for further optimizations and designs of Mpro's inhibitors with a high binding affinity.

Getting to the bottom of bycatch: a GIS-based toolbox to assess the risk of marine mammal bycatch

Marine mammal bycatch poses a particular challenge in developing countries, where data to document bycatch and its effects are often lacking. Using the Bycatch Risk Assessment (ByRA) toolkit, based on InVEST open-source models, we chose 4 field sites in Southeast Asia with varying amounts of data on marine mammals and fishing occurrence: Trat province in the eastern Gulf of Thailand, the Sibu-Tinggi Islands and Kuching Bay, Malaysia, and Kien Giang Biosphere Reserve in southwestern Vietnam. These field sites have similar species of coastal marine mammals, small-scale and commercial fisheries, and support for research from universities and/or management. In Thailand and Kuching, results showed changing patterns of fishing and Irrawaddy dolphin Orcaella brevirostris habitat use across seasons, showing how bycatch risk could change throughout the year. Risk maps for dugongs Dugong dugon in peninsular Malaysia highlighted patterns of bycatch risk concentrated around a mainland fishing pier, and revealed high risk in a northern subregion. In Vietnam, first maps of bycatch risk for the Irrawaddy dolphin showed the highest risk driven by intensive use of gillnets and trawling gear. ByRA pinpointed areas of spatial and seasonal bycatch exposure, and estimated the consequence of bycatch on local species, providing managers with critical information on where to focus bycatch mitigation and meet new global standards for US Marine Mammal Protection Act and other international regulation (e.g. Official Journal of the European Union 2019; Regulation 2019/1241) compliance. The toolbox, a transferable open-source tool, can be used to guide fisheries management, marine mammal conservation, spatial planning, and further research.

An evidence-based strategy to screen for pulmonary arterial hypertension in systemic sclerosis

BACKGROUND

Clinical practice guidelines recommend screening all systemic sclerosis (SSc) patients for pulmonary arterial hypertension (PAH) with yearly echocardiograms. There is a paucity of evidence to support these guidelines.

RESEARCH QUESTION

Can a prediction model identify SSc patients with a very low probability of PAH and therefore not requiring annual screening echocardiogram?

STUDY DESIGN AND METHODS

We performed a case-control study of 925 unselected SSc subjects nested in a multi-centered, longitudinal cohort. The probability of PAH for each subject was calculated using the results of multivariate logistic regression models. A cut-off was identified for the estimated probability of PAH below which no subject developed PAH (100% sensitivity).

RESULTS

Study subjects were predominantly female (87.5%), with mean (SD) age 58.6 (11.7) years and disease duration of 18.2 (12.2) years. Thirty-seven subjects developed PAH during 5407.97 person-years of observation (incidence rate 0.68 per 100 person-years). Shortness of breath (SOB), diffusing capacity for carbon monoxide (DLCO) and NT-proBNP were independent predictors of PAH. All SSc-PAH cases had a probability of PAH of >1.1%. Subjects below this cut-off, none of whom had PAH, accounted for 46.2% of the study population.

INTERPRETATION

A simple prediction model identified subjects at very low probability of PAH who could potentially forego annual screening echocardiogram. This represents almost half of SSc subjects in a general SSc population. This study, which is the first evidence-based study for the rational use of follow-up echocardiograms in an unselected SSc cohort, requires validation. The scoring system is freely available online at http://pahtool.ladydavis.ca.

Combining Docking Pose Rank and Structure with Deep Learning Improves Protein-Ligand Binding Mode Prediction over a Baseline Docking Approach

We present a simple, modular graph-based convolutional neural network that takes structural information from protein-ligand complexes as input to generate models for activity and binding mode prediction. Complex structures are generated by a standard docking procedure and fed into a dual-graph architecture that includes separate subnetworks for the ligand bonded topology and the ligand-protein contact map. Recent work has indicated that data set bias drives many past promising results derived from combining deep learning and docking. Our dual-graph network allows contributions from ligand identity that give rise to such biases to be distinguished from effects of protein-ligand interactions on classification. We show that our neural network is capable of learning from protein structural information when, as in the case of binding mode prediction, an unbiased data set is constructed. We next develop a deep learning model for binding mode prediction that uses docking ranking as input in combination with docking structures. This strategy mirrors past consensus models and outperforms a baseline docking program (AutoDock Vina) in a variety of tests, including on cross-docking data sets that mimic real-world docking use cases. Furthermore, the magnitudes of network predictions serve as reliable measures of model confidence.

Directional extraction and penetration of phosphorene nanosheets to cell membranes

Recently, phosphorene, a novel two-dimensional nanomaterial with a puckered surface morphology, was shown to exhibit cytotoxicity, but its underlying molecular mechanisms remain unknown. Herein, using large scale molecular dynamics simulations, we show that phosphorene nanosheets can penetrate into and extract large amounts of phospholipids from the cell membranes due to the strong dispersion interaction between phosphorene and lipid molecules, which would reduce cell viability. The extracted phospholipid molecules are aligned along the wrinkle direction of the phosphorene nanosheet because of its unique puckered structure. Our results also reveal that small phosphorene nanosheets penetrate into the cell membrane in a specific direction which is determined by the size and surface topography of phosphorene and the thickness of the membrane. These findings might shed light on understanding phosphorene's cytotoxicity and would be helpful for the future potential biomedical applications of phosphorene, such as biosensors and antibacterial agents.

P253 Withdrawal of beta- blockers and ACE inhibitors after left ventricular systolic function recovery in patient with dilated cardiomyopathy randomized control trial

Funding Acknowledgements

The Rosenfeld Heart Fund

Introduction

recovery of left ventricle (LV) systolic function with normalization of ejection fraction (LVEF) occurs in 10 - 27% of patients with 80% maintaining recovery. However, the need for medical therapy after recovery is often questioned. Previous randomized studies of treatment withdrawal were small, not selected for non-ischemic dilated cardiomyopathy (DCM) and had a reference of improved or recovered EF to &gt; 40% or &gt; 10% change from LVEF at time of diagnosis.  Hypothesis: In patients with DCM with recovery of the LV systolic function to an EF (&gt;50%), medical therapy withdrawal is possible without rebound LV systolic dysfunction. Method: This was a pilot randomized control open-label trial with 2:1 randomization for withdrawal of b-blockers and ACE inhibitors in patients with recovered LV systolic function. Patients’ medication discontinuation occurred in 2 phases with a six-month interval and patients were followed for one year. The primary endpoint was LVEF reduction (&lt; 40%). Results: There were 22 patients (10 females) enrolled. The mean age was 60 ± 12y. The mean LVEF at enrollment was 58 ± 5% with no significant difference in the mean LVEF in both groups. Sixteen patients were assigned to the withdrawal group and 6 assigned to the control group. The primary endpoint occurred in 31% of the withdrawal group compared to none of the control. The rate of 1ry outcome after withdrawal of medical therapy was 19%, p-value 0.15. The mean LVEF at 1 year for the treatment withdrawal group was 46.8 ± 12% and control 55 ± 6%, p-value 0.15. In the medication withdrawal group, the mean LVEF reduction was 10.6 ± 11% and the difference between the mean LVEF at enrollment and at 1 year was 10.6 ± 11% with 95% CI (4.6,16.49), p-value 0.0017. Conclusion: In DCM patients with recovery of LV systolic function, we observed worsening of LVEF after withdrawal of b-blockers and ACE inhibitors.

Abstract P253 Figure.

Intractable hypercalcaemia during pregnancy and the postpartum secondary to pathogenic variants in CYP24A1

SUMMARY

Parathyroid-independent hypercalcaemia of pregnancy, due to biallelic loss of function of the P450 enzyme CYP24A1, the principal inactivator of 1,25(OH)2D results in hypervitaminosis D, hypercalcaemia and hypercalciuria. We report two cases of this disorder, with intractable hypercalcaemia, one occurring during gestation and into the postpartum, and the other in the postpartum period. Case 1, a 47-year-old woman with a twin pregnancy conceived by embryo transfer, presented with hypercalcaemia at 23 weeks gestation with subnormal serum parathyroid hormone (PTH) and normal serum 25-OH D levels. She was admitted to hospital at 31 weeks gestation with pregnancy-induced hypertension, gestational diabetes and increasing hypercalcaemia. Caesarean section at 34 weeks gestation delivered two healthy females weighing 2.13 kg and 2.51 kg. At delivery, the patient's serum calcium level was 2.90 mmol/L. Postpartum severe hypercalcaemia was treated successfully with Denosumab 60 mg SCI, given on two occasions. CYP24A1 testing revealed she was compound heterozygous for pathogenic variants c.427_429delGAA, (p.Glu143del) and c.1186C>T, (p.Arg396Trp). Case 2, a 36-year-old woman presented 4 days after the delivery of healthy twins with dyspnoea, bradycardia, severe headaches, hypertension and generalized tonic-clonic seizures after an uneventful pregnancy. She was hypercalcaemic with a suppressed PTH, normal 25(OH)D, and elevated 1,25(OH)2D levels. Her symptoms partially responded to i.v. saline and corticosteroids in the short term but bisphosphonates such as Pamidronate and Zoledronic acid did not result in sustained improvement. Denosumab 120 mg SCI successfully treated the hypercalcaemia which resolved completely 2 months post-partum. CYP24A1 testing revealed she was homozygous for the pathogenic variant c.427_429delGAA, (p.Glu143del).

LEARNING POINTS

Hypercalcaemia in pregnancy can be associated with considerable morbidity with few options available for management. In non-PTH-related hypercalcaemia the diagnosis of CYP24A1 deficiency should be considered. Making a definitive diagnosis of CYP24A1 deficiency by genetic testing delays the diagnosis, while the availability of serum 24,25-dihydroxyvitamin D (24,25(OH)2D) will expedite a diagnosis. In pregnant women with CYP24A1 deficiency hypercalcaemia can worsen in the post-partum period and is more likely to occur with twin pregnancies but generally resolves within 2-3 months. Therapeutic alternatives are limited in pregnancy and their effectiveness is short-lived and mostly ineffective. Denosumab used in both our patients after delivery was the most effective agent normalizing calcium and may have benefit as a long-term therapeutic agent in preventing complications in patients with CYP24A1 deficiency.

P6350Impact of diabetes on serum biomarkers in heart failure with preserved ejection fraction: insights from the spironolactone for heart failure with preserved ejection fraction (TOPCAT) trial

Background and purpose

Diabetes mellitus (DM) is common in heart failure with preserved ejection fraction (HFpEF). Patients with DM and HF with reduced ejection fraction have higher levels of prognostic biomarkers relative to non-diabetics. We sought to examine differences in biomarkers at baseline and over time in patients with HFpEF with and without DM (non-DM).

Methods

The Americas cohort of the TOPCAT trial included 248 subjects with baseline measurements of serum biomarkers and follow-up measures 12 months later. Subjects were identified as non-DM or DM at baseline. Baseline values were compared using non-parametric tests and 12-month changes were compared via linear regression after log-transformation and adjustment for baseline biomarker value, age, gender, randomization strata, and randomized treatment.

Results

At baseline, DM patients had significantly lower eGFR and higher hsCRP, PIIINP, TIMP1, and Gal-3 levels versus non-DM patients (Table). In addition, there was a significantly larger increase over time in levels of hs-TnT, a marker of myocyte death, in DM vs. non-DM patients (p=0.016).

Baseline and 12-Month Biomarkers Baseline % Change at 12 Months Non-DM (n=132) DM (n=116) p Non-DM (n=110) DM (n=94) p eGFR (mL/min/1.73m2) 67 [57, 77] 57 [46, 73] 0.003 −14% (−17, −10) −14% (−18, −10) 0.34 hsCRP (mg/L) 2.4 [1.1, 5.6] 3.1 [1.6, 7.5] 0.046 1% (−5, 3) −11% (−27, 7) 0.54 NT-proBNP (pg/mL) 624 [338, 1235] 629 [278, 1429] 0.80 −2% (−12, 10) −5% (−21, 13) 0.48 hs-TNT (ng/mL) 5.7 [3.1, 12.4] 7.1 [3.7, 14.2] 0.17 −1% (−14, 13) 11% (−3, 27) 0.016 Soluble ST2 (ng/mL) 28 [22, 32] 28 [21, 35] 0.36 −1% (−7, 5) −4% (−9, 2) 0.60 Aldosterone (ng/L) 149 [120, 202] 142 [113, 174] 0.09 17% (9, 26) 23% (14, 33) 0.76 PICP (ng/mL) 137 [101, 169] 127 [102, 155] 0.29 5% (−5, 17) 1% (−9, 12) 0.07 CITP (ng/mL) 1.6 [1.0, 2.8] 1.6 [0.9, 3.0] 0.93 −25% (−37, 10) −23% (−36, −8) 0.87 PIIINP (ng/mL) 23 [16, 30] 28 [21, 36] <0.001 5% (−4, 15) 5% (−3, 14) 0.12 TIMP-1 (ng/mL) 188 [170, 212] 212 [183, 245] <0.001 −1% (−4, 2) −2% (−5, 2) 0.59 Galectin-3 (ng/mL) 20 [16, 23] 22 [18, 28] <0.001 6% (3, 10) 9% (4, 14) 0.52 eGFR, estimated glomerular filtration rate; hsCRP, high-sensitivity CRP; NT-proBNP, N-terminal pro-B-type natriuretic peptide; hs-TnT, high-sensitivity troponin T; PICP, pro-collagen type I carboxy-terminal peptide; CITP, collage type I; PIIINP=pro-collagen type III amino-terminal peptide; TIMP-1=tissue inhibitor of MMP-1.

Conclusions

In comparison to patients without DM, those with DM had poorer renal function and higher baseline levels of markers of myocardial stretch, myocyte death, and pro-fibrotic biomarkers. Further, hs-TnT increased over 12 months only in patients with DM.

Lanosterol Disrupts the Aggregation of Amyloid-β Peptides

Lanosterol, an amphipathic molecule, was discovered only very recently to effectively hinder the aggregation of lens proteins and dissolve the extremely stable fibrillar aggregates in cataracts. Here, we combined computational and experimental approaches to study how lanosterol disrupts the aggregation of another important peptide, amyloid-β (Aβ) peptide, associated with the Alzheimer's Disease (AD). Molecular dynamics simulations using the core amyloidogenic segment (KLVFFA) of Aβ peptide revealed that lanosterol exhibits at least two types of inhibition mechanism on the self-assembly of Aβ peptides. First, lanosterol entangles with peptides and forms a hydrophobic core with residues Phe-19 and Phe-20 in particular. Second, it interferes with the steric zipper interaction at the β-sheet-β-sheet interface. These simulation data suggest that lanosterol induces the unfolding of the Aβ peptide and the separation of the β-sheet layers. This predicted inhibition effect of lanosterol was then confirmed by an in vitro ThT fluorescence assay and AFM imaging. The cell toxicity assay also showed that the treatment of lanosterol indeed mitigates the cytotoxicity of the Aβ peptide in PC-12 cells. Moreover, lanosterol shows a stronger suppression effect on Aβ peptides' aggregation than cholesterol because of its higher hydrophobicity. This result establishes a foundation for the development of lanosterol-based potential therapies for AD and other protein conformational diseases.

Understanding glycaemic control and current approaches for screening antidiabetic natural products from evidence-based medicinal plants

Type 2 Diabetes Mellitus has reached epidemic proportions as a result of over-nutrition and increasingly sedentary lifestyles. Current therapies, although effective, are not without limitations. These limitations, the alarming increase in the prevalence of diabetes, and the soaring cost of managing diabetes and its complications underscores an urgent need for safer, more efficient and affordable alternative treatments. Over 1200 plant species are reported in ethnomedicine for treating diabetes and these represents an important and promising source for the identification of novel antidiabetic compounds. Evaluating medicinal plants for desirable bioactivity goes hand-in-hand with methods in analytical biochemistry for separating and identifying lead compounds. This review aims to provide a comprehensive summary of current methods used in antidiabetic plant research to form a useful resource for researchers beginning in the field. The review summarises the current understanding of blood glucose regulation and the general mechanisms of action of current antidiabetic medications, and combines knowledge on common experimental approaches for screening plant extracts for antidiabetic activity and currently available analytical methods and technologies for the separation and identification of bioactive natural products. Common in vivo animal models, in vitro models, in silico methods and biochemical assays used for testing the antidiabetic effects of plants are discussed with a particular emphasis on in vitro methods such as cell-based bioassays for screening insulin secretagogues and insulinomimetics. Enzyme inhibition assays and molecular docking are also highlighted. The role of metabolomics, metabolite profiling, and dereplication of data for the high-throughput discovery of novel antidiabetic agents is reviewed. Finally, this review also summarises sample preparation techniques such as liquid-liquid extraction, solid phase extraction, and supercritical fluid extraction, and the critical function of nuclear magnetic resonance and high resolution liquid chromatography-mass spectrometry for the dereplication, putative identification and structure elucidation of natural compounds from evidence-based medicinal plants.