Structural analysis and insight into novel MMP-13 inhibitors from natural chemiome as disease-modifying osteoarthritis drugs

Purpose: To identify natural chemiome that inhibits matrix-metalloproteinases (MMPs) with a view to discovering novel disease-modifying osteoarthritis drugs (DMOADs).Methods: Computer-aided drug design (CADD) with virtual screening, ADME/Tox, molecular docking, molecular dynamics simulation, and MM-PBSA calculations were used in search of novel natural compounds that inhibit MMPs.Results: From more than fifty thousand compounds, a single lead compound (IBS ID: 77312) was shortlisted using bias based on binding energy and drug-likeness. This lead compound synergistically bound to the S1 domain of MMP-13 protein through five hydrogen bonds. The interactions became stable within 100-nanosecond molecular dynamics simulation run. The in vitro data for the lead compound showed that its minimal non-lethal dose increased collagen content but decreased aggrecan level in chondrocytes.Conclusion: This study has identified a natural lead compound that may pave the way for a novel DMOAD of natural origin against OA.Keywords: Osteoarthritis, MMP-13, Natural chemiome, Disease-modifying osteoarthritis drug, Molecular dockin

Genome-wide identification and characterization of the NPF genes provide new insight into low nitrogen tolerance in Setaria

IntroductionNitrogen (N) is essential for plant growth and yield production and can be taken up from soil in the form of nitrate or peptides. The NITRATE TRANSPORTER 1/PEPTIDE TRANSPORTER family (NPF) genes play important roles in the uptake and transportation of these two forms of N.MethodsBioinformatic analysis was used to identify and characterize the NPF genes in Setaria. RNA-seq was employed to analyze time-series low nitrate stress response of the SiNPF genes. Yeast and Arabidopsis mutant complementation were used to test the nitrate transport ability of SiNRT1.1B1 and SiNRT1.1B2.ResultsWe identified 92 and 88 putative NPF genes from foxtail millet (Setaria italica L.) and its wild ancestor green foxtail (Setaria viridis L.), respectively. These NPF genes were divided into eight groups according to their sequence characteristics and phylogenetic relationship, with similar intron-exon structure and motifs in the same subfamily. Twenty-six tandem duplication and 13 segmental duplication events promoted the expansion of SiNPF gene family. Interestingly, we found that the tandem duplication of the SiNRT1.1B gene might contribute to low nitrogen tolerance of foxtail millet. The gene expression atlas showed that the SiNPFs were divided into two major clusters, which were mainly expressed in root and the above ground tissues, respectively. Time series transcriptomic analysis further revealed the response of these SiNPF genes to short- and long- time low nitrate stress. To provide natural variation of gene information, we carried out a haplotype analysis of these SiNPFs and identified 2,924 SNPs and 400 InDels based on the re-sequence data of 398 foxtail millet accessions. We also predicted the three-dimensional structure of the 92 SiNPFs and found that the conserved proline 492 residues were not in the substrate binding pocket. The interactions of SiNPF proteins with NO3− were analyzed using molecular docking and the pockets were then identified. We found that the SiNPFs- NO3− binding energy ranged from -3.8 to -2.7 kcal/mol.DiscussionTaken together, our study provides a comprehensive understanding of the NPF gene family in Setaria and will contribute to function dissection of these genes for crop breeding aimed at improving high nitrogen use efficiency

Elian granules alleviate precancerous lesions of gastric cancer in rats by suppressing M2-type polarization of tumor-associated macrophages through NF-κB signaling pathway

Abstract Background Precancerous lesions of gastric cancer (PLGC) refer to a kind of histopathological changes in the gastric mucosa that can progress to gastric cancer. Elian granules (ELG), a Chinese medicinal prescription, have achieved satisfactory results in the treatment of PLGC. However, the exact mechanism underlying the therapeutic effect of ELG remains unclear. Here, this study aims to explore the mechanism of ELG alleviating PLGC in rats. Methods The chemical ingredients of ELG were analyzed using ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS). Specific Pathogen Free SD rats were randomly assigned to 3 groups: the control, model, and ELG groups. The 1-Methyl-3-nitro-1-nitrosoguanidine (MNNG) integrated modeling method was adopted to construct the PLGC rat model in groups except for the control group. Meanwhile, normal saline was used as an intervention for the control and model groups, and ELG aqueous solution for the ELG group, lasting 40 weeks. Subsequently, the stomach of rats was harvested for further analysis. Hematoxylin-eosin staining of the gastric tissue was conducted to assess the pathological changes. Immunofluorescence was carried out for the expression of CD68, and CD206 proteins. Real-time quantitative PCR combined with Western blot was conducted to analyze the expression of arginase-1(Arg-1), inducible nitric oxide synthase (iNOS), p65, p-p65, nuclear factor inhibitor protein-α (IκBα), and p-IκBα in gastric antrum tissue. Results Five chemical ingredients including Curcumol, Curzerenone, Berberine, Ferulic Acid, and 2-Hydroxy-3-Methylanthraquine were identified in ELG. The gastric mucosal glands of rats treated with ELG were orderly arranged, with no intestinal metaplasia and no dysplasia. Furthermore, ELG decreased the percentage of M2-type TAMs marked with CD68 and CD206 proteins, and the ratio of Arg-1 to iNOS in the gastric antrum tissue of rats with PLGC. In addition, ELG could also down-regulate the protein and mRNA expression of p-p65, p65, and p-IκBα, but up-regulate the expression of IκBα mRNA in rats with PLGC. Conclusions The results showed that ELG attenuates PLGC in rats by suppressing the M2-type polarization of tumor-associated macrophages (TAMs) through NF-κB signaling pathway

Simultaneous delivery of therapeutic antagomirs with paclitaxel for the management of metastatic tumors by a pH-responsive anti-microbial peptide-mediated liposomal delivery system

The roles of microRNAs (miRNAs) in the regulation of metastasis have been widely recognized in the recent years. Mir-10b antagomir (antagomir-10b) was shown to impede metastasis through the down-regulation of mir-10b; however, it could not stunt the growth of primary tumors. In this study we showed that the co-delivery of antagomir-10b with paclitaxel (PTX) by a novel liposomal delivery system modified with an anti-microbial peptide [D]-H6L9 (D-Lip) could significantly both hinder the migration of 4 T1 cells and induce evident cellular apoptosis and cell death in the meantime. The histidines in the sequence of [D]-H6L9 allowed the peptide to get protonated under pH 5.0 (mimicking the lysosome/endosome environment), and strong membrane lytic effect could thus be activated, leading to the escape of liposomes from the lysosomes and the decrease of of mir-10b expression. The in vivo and ex vivo fluorescence imaging showed that D-Lip could reach 4 T1 tumors efficaciously. Incorporation of PTX did not influence the antagomir-10b delivery effect of D-Lip; for the in vivo tumor inhibition assay, compared with all the other groups, the combination of antagomir-10b and PTX delivered by D-Lip could prominently delay the growth of 4 T1 tumors and reduce the lung metastases at the same time, and the expression of Hoxd10 in tumors was also significantly up-regulated. Taken together, these results demonstrated that D-Lip could act as a sufficient tool in co-delivering antagomir-10b and PTX

Heatwave exposure in relation to decreased sleep duration in older adults

Few studies have delved into the effects of heatwaves on sleep duration loss among older adults. Our study examined correlations between heatwave exposure and sleep duration reductions in this demographic. Utilizing data of 7,240 older adults drawn from the China Health and Retirement Longitudinal Study (CHARLS) from 2015 to 2018, we assessed sleep duration differences between the baseline year (2015) and follow-up year (2018). Absolute reductions in sleep duration were defined as differences of ≥ 1, 1.5, or 2 h. Changes in sleep duration were categorized based on cut-offs of 5 and 8 h, including excessive decrease, moderate to short and persistent short sleep duration types. 12 heatwave definitions combining four thresholds (90th, 92.5th, 95th, and 97.5th percentiles of daily minimum temperature) and three durations (≥2, ≥3 and ≥ 4 days) were used. Heatwave exposure was determined by the difference in the number of 12 preceding months' heatwave days or events in 2015 and the number of 12 preceding months' heatwave days or events in 2018. The results showed that increased heatwave events (defined as ≥ P90th percentile & lasting three days) were associated with a higher likelihood of ≥ 1-hour sleep reduction and persistent short sleep duration. An increase in heatwave event (defined as ≥ P95th percentile & lasting three days) was linked to shifts from moderate to short sleep duration. For the association between an absolute reduction in sleep duration and heatwave exposure, while higher thresholds signified greater sleep reduction risks, the effect estimates of longer durations were not uniformly consistent. We observed that air pollution and green space modified the relationship between heatwaves and sleep duration. Females, urban residents, and individuals with chronic diseases were identified as vulnerable populations. This study found that increased heatwave exposure was associated with a higher risk of sleep duration loss in older adults

Paclitaxel loaded liposomes decorated with a multifunctional tandem peptide for glioma targeting

The treatment of glioma is a great challenge because of the existence of the blood-brain barrier (BBB). In order to reduce toxicity to the normal brain tissue and achieve efficient treatment, it is also important for drugs to specifically accumulate in the glioma foci and penetrate into the tumor core after entering into the brain. In this study, a specific ligand cyclic RGD peptide was conjugated to a cell penetrating peptide R8 to develop a multifunctional peptide R8-RGD. R8-RGD increased the cellular uptake of liposomes by 2-fold and nearly 30-fold compared to separate R8 and RGD respectively, and displayed effective penetration of three-dimensional glioma spheroids and BBB model in vitro. In vivo studies showed that R8-RGD-lipo could be efficiently delivered into the brain and selectively accumulated in the glioma foci after systemic administration in C6 glioma bearing mice. When paclitaxel (PTX) was loaded in liposomes, R8-RGD-lipo could induce the strongest inhibition and apoptosis against C6 cells and finally achieved the longest survival in intracranial C6 glioma bearing mice. In conclusion, all the results indicated that the tandem peptide R8-RGD was a promising ligand possessing multi functions including BBB transporting, glioma targeting and tumor penetrating. And R8-RGD-lipo was proved to be a potential anti-glioma drug delivery system

Targeted Delivery of Cargoes into a Murine Solid Tumor by a Cell-Penetrating Peptide and Cleavable Poly(ethylene glycol) Comodified Liposomal Delivery System via Systemic Administration

A liposomal delivery system with a high efficiency of accumulation in tumor tissue and then transportation of the cargo into tumor cells was developed here and evaluated via systemic administration. 1,2-Distearoyl-sn-glycero-3-phosphoethanolamine-poly(ethylene glycol)2000 (DSPE-PEG2000)-TAT and protective DSPE-PEG2000 modified liposomes possessing good stability in 50% FBS (fetal bovine serum) and good uptake efficiency were used as the basic formulation (TAT-SL; SL = stealth liposome), and then longer cysteine (Cys)-cleavable PEG5000 was incorporated to modulate the function of TAT. All of the formulations to be used in vivo had sizes in a range of 80–100 nm and were stable in the presence of 50% FBS. Optical imaging showed that the incorporation of cleavable PEG5000 into TAT-SL (i.e., C-TAT-SL) led to much more tumor accumulation and much less liver distribution compared with TAT-SL. The in vivo delivery profiles of C-TAT-SL were investigated using DiD as a fluorescent probe. Confocal laser scanning microscopy and flow cytometry showed that C-TAT-SL had a 48% higher (p < 0.001) delivery efficiency in the absence of Cys and a 130% higher (p < 0.001) delivery efficiency in the presence of Cys than the control (SL), indicating the successful targeted delivery of cargo was achieved by C-TAT-SL via systemic administration especially with a subsequent administration of Cys