Antimony efflux underpins phosphorus cycling and resistance of phosphate-solubilizing bacteria in mining soils.

Microorganisms play crucial roles in phosphorus (P) turnover and P bioavailability increases in heavy metal-contaminated soils. However, microbially driven P-cycling processes and mechanisms of their resistance to heavy metal contaminants remain poorly understood. Here, we examined the possible survival strategies of P-cycling microorganisms in horizontal and vertical soil samples from the world's largest antimony (Sb) mining site, which is located in Xikuangshan, China. We found that total soil Sb and pH were the primary factors affecting bacterial community diversity, structure and P-cycling traits. Bacteria with the gcd gene, encoding an enzyme responsible for gluconic acid production, largely correlated with inorganic phosphate (Pi) solubilization and significantly enhanced soil P bioavailability. Among the 106 nearly complete bacterial metagenome-assembled genomes (MAGs) recovered, 60.4% carried the gcd gene. Pi transportation systems encoded by pit or pstSCAB were widely present in gcd-harboring bacteria, and 43.8% of the gcd-harboring bacteria also carried the acr3 gene encoding an Sb efflux pump. Phylogenetic and potential horizontal gene transfer (HGT) analyses of acr3 indicated that Sb efflux could be a dominant resistance mechanism, and two gcd-harboring MAGs appeared to acquire acr3 through HGT. The results indicated that Sb efflux could enhance P cycling and heavy metal resistance in Pi-solubilizing bacteria in mining soils. This study provides novel strategies for managing and remediating heavy metal-contaminated ecosystems.

Quercetin Inhibits KBM7R Cell Proliferation through Wnt/ß-Catenin Signaling.

Background: Tyrosine kinase inhibitors could treat chronic myelogenous leukemia (CML) effectively, but they have no effect on patients with T315I mutation. It is necessary to find drugs to overcome the resistance. Quercetin (Qu) is a kind of bioflavonoid with an antitumor effect. In this study, we observed the effect of Qu on proliferation and Wnt/ß-catenin pathway in KBM7R cells, an imatinib-resistant cell with T315I mutation. Methods: The IC50 of Qu was detected by trypan blue staining. The KBM7R cell apoptosis and cycle were detected through the method of flow cytometry (FCM). The expression of the related mRNA and protein was evaluated by means of an RT-PCR assay and western blot in KBM7 (sensitive to IM) and KBM7R cells. Results: These results showed that in the KBM7R cell, the proliferation inhibition effect was increased after 48 h administration with different Qu concentrations. The IC50 to Qu was 241.7 µmol/L. The different doses of Qu (50, 100, and 200 µmol/L) would raise apoptosis and depress the cell cycle at the G1 phase. Dealing with a median Qu concentration (100 µmol/L) for 48 h, the mRNA and the protein level of caspase-3, caspase-8, and caspase-9 along with p21 and p27 raised compared with the control. The median concentration of Qu could inhibit both the mRNA and protein levels of GSK-3ß, ß-catenin, and Lef-1 in the Wnt/ß-catenin signal pathway and also the downstream targets PPAR-δ and cyclin D1 in both KBM7 and KBM7R cells. Conclusions: Our findings suggest that Qu could inhibit proliferation, induce apoptosis, and arrest the cell cycle on IM-resistant KBM7R cells with T315I mutation. And this effect could be related with the inhibition of the Wnt/ß-catenin signal pathway and downstream targets.

PCycDB: a comprehensive and accurate database for fast analysis of phosphorus cycling genes.

BACKGROUND: Phosphorus (P) is one of the most essential macronutrients on the planet, and microorganisms (including bacteria and archaea) play a key role in P cycling in all living things and ecosystems. However, our comprehensive understanding of key P cycling genes (PCGs) and microorganisms (PCMs) as well as their ecological functions remains elusive even with the rapid advancement of metagenome sequencing technologies. One of major challenges is a lack of a comprehensive and accurately annotated P cycling functional gene database. RESULTS: In this study, we constructed a well-curated P cycling database (PCycDB) covering 139 gene families and 10 P metabolic processes, including several previously ignored PCGs such as pafA encoding phosphate-insensitive phosphatase, ptxABCD (phosphite-related genes), and novel aepXVWPS genes for 2-aminoethylphosphonate transporters. We achieved an annotation accuracy, positive predictive value (PPV), sensitivity, specificity, and negative predictive value (NPV) of 99.8%, 96.1%, 99.9%, 99.8%, and 99.9%, respectively, for simulated gene datasets. Compared to other orthology databases, PCycDB is more accurate, more comprehensive, and faster to profile the PCGs. We used PCycDB to analyze P cycling microbial communities from representative natural and engineered environments and showed that PCycDB could apply to different environments. CONCLUSIONS: We demonstrate that PCycDB is a powerful tool for advancing our understanding of microbially driven P cycling in the environment with high coverage, high accuracy, and rapid analysis of metagenome sequencing data. The PCycDB is available at https://github.com/ZengJiaxiong/Phosphorus-cycling-database . Video Abstract.

ß-Caryophyllene suppresses ferroptosis induced by cerebral ischemia reperfusion via activation of the NRF2/HO-1 signaling pathway in MCAO/R rats.

BACKGROUND: Ischemic stroke is a complex brain disease regulated by several cell death processes, including apoptosis, autophagy, and ferroptosis. ß-Caryophyllene (BCP), a natural bicyclic sesquiterpene abundantly found in essential oils, has been demonstrated to have potential pharmacological benefits in many diseases, including ischemic stroke. PURPOSE: This research was to determine the existence of ferroptosis in the pathogenesis of acute ischemic stroke and investigate whether BCP can inhibit ferroptosis to improve cerebral ischemia injury by activating the NRF2/HO-1 signaling pathway in rats. METHODS: First, we verified ferroptosis by assessing proferroptotic changes after middle cerebral artery occlusion reperfusion (MCAO/R), along with protein and lipid peroxidation levels. Then male rats were divided randomly into Sham, MCAO/R, ML385 (NRF2-specific inhibitor) and BCP groups. The effects of BCP on cerebral injury were detected by the modified neurological severity score, TTC staining, and hematoxylin-eosin staining. We conducted western blotting analyzes of proteins, including those involved in ferroptosis and related signaling pathways. To demonstrate the neuroprotective effect of BCP in vitro, primary astrocytes were pretreated with different concentrations of BCP (10, 20, and 40 µM) for 24 h before oxygen-glucose deprivation/re-oxygenation (ODG/R). RESULTS: We concluded that ferroptosis was engaged in the process of I/R-induced neurological damage, implying that this novel type of cell death might provide new therapeutic options for the clinical treatment of ischemic stroke. In vivo study proved that BCP improved neurological scores, infarct volume, and pathological features after MCAO/R. We demonstrated that BCP evidently enhanced NRF2 nuclear translocation, activated the NRF2/HO-1 pathway, which protected against ferroptosis. In vitro investigation revealed the same results. BCP decreased OGD/R-induced ROS generation and iron accumulation. Furthermore, the neuroprotective effects of BCP were reversed by the NRF2 inhibitor ML385. CONCLUSION: Our results indicated the critical role of ferroptosis in cerebral I/R injury. For the first time, we showed that the significant neuroprotective effects of BCP in attenuating ischemic stroke injury are correlated with ferroptosis regulation, and its mechanism is associated with activation of the NRF2/HO-1 axis.

Enhancing and Complementary Mechanisms of Synergistic Action of Acori Tatarinowii Rhizoma and Codonopsis Radix for Alzheimer's Disease Based on Systems Pharmacology.

MATERIALS AND METHODS: In this study, a systems pharmacology-based strategy was used to elucidate the synergistic mechanism of Acori Tatarinowii Rhizoma and Codonopsis Radix for the treatment of AD. This novel systems pharmacology model consisted of component information, pharmacokinetic analysis, and pharmacological data. Additionally, the related pathways were compressed using the Kyoto Encyclopedia of Genes and Genomes (KEGG) database, and the organ distributions were determined in the BioGPS bank. RESULTS: Sixty-eight active ingredients with suitable pharmacokinetic profiles and biological activities were selected through ADME screening in silico. Based on 62 AD-related targets, such as APP, CHRM1, and PTGS1, systematic analysis showed that these two herbs were mainly involved in the PI3K-Akt signaling pathway, MAPK signaling pathway, neuroactive ligand-receptor interaction, and fluid shear stress and atherosclerosis, indicating that they had a synergistic effect on AD. However, ATR acted on the KDR gene, while CR acted on IGF1R, MET, IL1B, and CHUK, showing that they also had complementary effects on AD. The ingredient contribution score involved 29 ingredients contributing 90.14% of the total contribution score of this formula for AD treatment, which emphasized that the effective therapeutic effects of these herbs for AD were derived from both ATR and CR, not a single herb. Organ distribution showed that the targets of the active ingredients were mainly located in the whole blood, the brain, and the muscle, which are associated with AD. CONCLUSIONS: In sum, our findings suggest that the systems pharmacology methods successfully revealed the synergistic and complementary mechanisms of ATR and CR for the treatment of AD.