Downregulated BMP-Smad1/5/8 signaling causes emphysema via dysfunction of alveolar type II epithelial cells.

Bone morphogenetic protein (BMP)-Smad1/5/8 signaling plays a crucial regulatory role in lung development and adult lung homeostasis. However, it remains elusive whether BMP-Smad1/5/8 signaling is involved in the pathogenesis of emphysema. In this study, we downregulated BMP-Smad1/5/8 signaling by overexpressing its antagonist Noggin in adult mouse alveolar type II epithelial cells (AT2s), resulting in an emphysematous phenotype mimicking the typical pathological features of human emphysema, including distal airspace enlargement, pulmonary inflammation, extracellular matrix remodeling, and impaired lung function. Dysregulation of BMP-Smad1/5/8 signaling in AT2s leads to inflammatory destruction dominated by macrophage infiltration, associated with reduced secretion of surfactant proteins and inhibition of AT2 proliferation and differentiation. Reactivation of BMP-Smad1/5/8 signaling by genetics or chemotherapy significantly attenuated the morphology and pathophysiology of emphysema and improved the lung function in Noggin-overexpressing lungs. We also found that BMP-Smad1/5/8 signaling was downregulated in cigarette smoke-induced emphysema, and that enhancing its activity in AT2s prevented or even reversed emphysema in the mouse model. Our data suggest that BMP-Smad1/5/8 signaling, located at the top of the signaling cascade that regulates lung homeostasis, represents a key molecular regulator of alveolar stem cell secretory and regenerative function, and could serve as a potential target for future prevention and treatment of pulmonary emphysema. © 2023 The Pathological Society of Great Britain and Ireland.

Elevational distribution and occurrence of arbuscular mycorrhizal fungi in non-host Carex capillacea.

Little is known about Arbuscular mycorrhizal (AM) fungal colonization and community composition in non-mycorrhizal (NM) plants, especially along elevational gradients. This study explores this question using a NM plant, Carex capillacea, at Mount Segrila, Tibet. Here, C. capillacea, its rhizosphere soil, and the neighboring mycotrophic plant Poa annua were sampled at four elevations to evaluate and compare their AM fungi colonization and communities. The results showed that AM fungal colonization density of C. capillacea was negatively correlated with elevation and biomass of total NM plants per quadrat. AM fungal diversity and community composition between C. capillacea and P. annua showed a similar pattern. In addition, elevation and soil did not significantly influence the AM community in C. capillacea, while they were important abiotic factors for assemblages in rhizosphere soil and P. annua. These findings support that a broad array of AM fungi colonize the root of C. capillacea, and a mycelial network from a co-occurring host plant might shape the AM fungal communities in C. capillacea along the elevation gradient. The co-occurrence patterns of AM fungi associated with non-mycotrophic species and adjacent mycotrophic species have important implications for understanding AM fungal distribution patterns and plant-AM interactions.

Combined structure-based virtual screening and machine learning approach for the identification of potential dual inhibitors of ACC and DGAT2.

Acetyl-coenzyme A carboxylase (ACC) and diacylglycerol acyltransferase 2 (DGAT2) are recognized as potential therapeutic targets for nonalcoholic fatty liver disease (NAFLD). Inhibitors targeting ACC and DGAT2 have exhibited the capacity to reduce hepatic fat in individuals afflicted with NAFLD. However, there are no reports of dual inhibitors targeting ACC and DGAT2 for the treatment of NAFLD. Here, we aimed to identify potential dual inhibitors of ACC and DGAT2 using an integrated in silico approach. Machine learning-based virtual screening of commercial molecule databases yielded 395,729 hits, which were subsequently subjected to molecular docking aimed at both the ACC and DGAT2 binding sites. Based on the docking scores, nine compounds exhibited robust interactions with critical residues of both ACC and DGAT2, displaying favorable drug-like features. Molecular dynamics simulations (MDs) unveiled the substantial impact of these compounds on the conformational dynamics of the proteins. Furthermore, binding free energy assessments highlighted the notable binding affinities of specific compounds (V003-8107, G340-0503, Y200-1700, E999-1199, V003-6429, V025-4981, V006-1474, V025-0499, and V021-8916) to ACC and DGAT2. The compounds proposed in this study, identified using a multifaceted computational strategy, warrant experimental validation as potential dual inhibitors of ACC and DGAT2, with implications for the future development of novel drugs targeting NAFLD.

Discovery of novel cholesteryl ester transfer protein (CETP) inhibitors by a multi-stage virtual screening.

Cholesteryl ester transfer protein (CETP) is a promising therapeutic target for cardiovascular diseases. It effectively lowers the low-density lipoprotein cholesterol levels and increases the high-density lipoprotein cholesterol levels in the human plasma. This study identified novel and highly potent CETP inhibitors using virtual screening techniques. Molecular docking and molecular dynamics (MD) simulations revealed the binding patterns of these inhibitors, with the top 50 compounds selected according to their predicted binding affinity. Protein-ligand interaction analyses were performed, leading to the selection of 26 compounds for further evaluation. A CETP inhibition assay confirmed the inhibitory activities of the selected compounds. The results of the MD simulations revealed the structural stability of the protein-ligand complexes, with the binding site remaining significantly unchanged, indicating that the five compounds (AK-968/40709303, AG-690/11820117, AO-081/41378586, AK-968/12713193, and AN-465/14952302) identified have the potential as active CETP inhibitors and are promising leads for drug development.

Effects of Amendments and Indigenous Microorganisms on the Growth and Cd and Pb Uptake of Coriander (Coriandrum sativum L.) in Heavy Metal-Contaminated Soils.

Heavy metal (HM) contamination of soils is a worldwide problem with adverse consequences to the environment and human health. For the safe production of vegetables in contaminated soil, efficient soil amendments need to be applied such as nano-hydroxyapatite (n-HAP) and poly γ-glutamic acid (γ-PGA), which can mitigate heavy metal uptake and enhance crop yield. However, the combined effects of soil amendments and indigenous microorganisms (IMOs) on HMs immobilisation and accumulation by crops have received little attention. We established a pot experiment to investigate the effects of IMOs combined with n-HAP and γ-PGA on coriander (Coriandrum sativum L.) growth and its Cd and Pb uptake in two acidic soils contaminated with HMs. The study demonstrated that applying n-HAP, with and without IMOs, significantly increased shoot dry biomass and reduced plant Cd and Pb uptake and diethylenetriaminepentaacetic acid (DTPA) extractable Cd and Pb concentrations in most cases. However, γ-PGA, with and without IMOs, only reduced soil DTPA-extractable Pb concentrations in slightly contaminated soil with 0.29 mg/kg Cd and 50.9 mg/kg Pb. Regardless of amendments, IMOs independently increased shoot dry biomass and soil DTPA-extractable Cd concentrations in moderately contaminated soil with 1.08 mg/kg Cd and 100.0 mg/kg Pb. A synergistic effect was observed with a combined IMOs and n-HAP treatment, where DTPA-extractable Cd and Pb concentrations decreased in slightly contaminated soil compared with the independent IMOs and n-HAP treatments. The combined treatment of γ-PGA and IMOs substantially increased shoot dry biomass in moderately contaminated soil. These results indicate that solo n-HAP enhanced plant growth and soil Cd and Pb immobilisation, and mitigated Cd and Pb accumulation in shoots. However, the combination of n-HAP and IMOs was optimal for stabilising and reducing HMs' uptake and promoting plant growth in contaminated soil, suggesting its potential for safe crop production.

Enhanced iron(III) reduction following amendment of paddy soils with biochar and glucose modified biochar.

Although biochar application to paddy fields has been widely studied, its effects on Fe(III) reduction have not yet been investigated. Paddy soil slurry and soil microbial inoculation incubation were conducted with unmodified biochar (UMB) or glucose-modified biochar (GMB) additions at different particle sizes. The Fe(II) concentration and pH value were determined regularly, and Fe(III) reducing capacity (FeRC) was evaluated by modeling. Fe(III) reduction potential (a) was increased by 0-1.96 mg g-1 in response to UMBs addition, and a more remarkable increase in a was related to the decrease of particle size. The dissolved organic carbon of UMBs was responsible for the majority of the biochar reducing capacity. UMBs addition increased the contribution of free Fe and nitrate nitrogen to FeRC, while it decreased that of available phosphorus. Moreover, GMBs led to greater promotion of FeRC than the corresponding UMBs, with an increase in a of 2.9-16% in soil slurry and reduction rate of 13-35% in microbial inoculation incubation. The maximum Fe(III) reduction rate (V max) with GMBs addition was faster or invariable than UMBs, while the time to V max (T Vmax) was shorter or stable. The effect of GMBs on Fe(III) reduction was less sensitive as GMB particle size increased. Compared with UMBs addition, pH declined remarkably in response to GMBs. These findings suggest that GMBs can effectively stimulate Fe(III) reduction in paddy fields, while simultaneously alleviating the pH increase usually caused by pristine biochar application.