Dauricine attenuates ovariectomized-induced bone loss and RANKL-induced osteoclastogenesis via inhibiting ROS-mediated NF-κB and NFATc1 activity.

BACKGROUND: Osteoclast plays an important role in maintaining the balance between bone anabolism and bone catabolism. The abnormality of osteoclast is closely related to osteolytic bone diseases such as osteoporosis, rheumatoid arthritis and tumor bone metastasis. PURPOSE: We aim to search for natural compound that may suppress osteoclast formation and function. STUDY DESIGN: In this study, we assessed the impact of Dauricine (Dau) on the formation and function of osteoclasts in vitro, as well as its potential in preventing bone loss in an ovariectomy mouse model in vivo. METHODS: Multiple in vitro experiments were carried out, including osteoclastogenesis, podosomal belt formation, bone resorption assay, RNA-sequencing, real-time quantitative PCR, ROS level detection, surface plasmon resonance assay, luciferase assay and western blot. To verify the effect in vivo, an ovariectomized mouse model (OVX model) was constructed, and bone parameters were measured using micro-CT and histology. Furthermore, metabolomics analysis was performed on blood serum samples from the OVX model. RESULTS: In vitro experiments demonstrated that Dau inhibits RANKL-induced osteoclastogenesis, podosomal belt formation, and bone resorption function. RNA-sequencing results revealed that Dau significantly suppresses genes related to osteoclast. Functional enrichment analysis indicated that Dau's inhibition of osteoclasts may be associated with NF-κB signaling pathway and reactive oxygen metabolism pathway. Molecular docking, surface plasmon resonance assay and western blot analysis further confirmed that Dau inhibits RANKL-induced osteoclastogenesis by modulating the ROS/NF-κB/NFATc1 pathway. Moreover, administration of Dau to OVX-induced mice validated its efficacy in treating bone loss disease. CONCLUSION: Dau prevents OVX-induced bone loss by inhibiting osteoclast activity and bone resorption, potentially offering a new approach for preventing and treating metabolic bone diseases such as osteoporosis. This study provides innovative insights into the inhibitory effects of Dau in an in vivo OVX model and elucidates the underlying mechanism.

[Availability Changes in Different Exogenous Selenium Fertilizers in Soil and Their Effects on Selenium Accumulation in Wheat].

In order to understand the differences in the uptake and accumulation of several common exogenous selenium fertilizers by crops, a wheat pot experiment was conducted to study the availability changes in different selenium fertilizers (potassium selenate, potassium selenite, EDTA-chelated selenium, selenium powder, fly ash, and selenium-enriched straw) in soil and their effects on wheat growth and selenium uptake and distribution. The results showed that the change in availability of different exogenous selenium types in soil was different. During the whole growth period of wheat, the soil available selenium proportion of selenate, selenite, and EDTA-chelated selenium treatment was significantly higher than that of the control (CK), respectively, but there was no significant difference between the other treatments and the CK treatment. In the early stage of wheat growth, the soil available selenium proportion of selenate, selenite, and selenium powder treatment decreased gradually and tended to be stable in the later growth stage of wheat; however, the soil available selenium proportion of other exogenous selenium treatments showed a dynamic change of decreasing in the early period and increasing in the late period. The available selenium content in soil significantly affected the selenium uptake by wheat, and there was a significant positive correlation between them. Selenate application significantly increased the grain and leaf biomass of wheat, but other selenium fertilizers had no significant effect on wheat growth. The accumulation capacity of different exogenous selenium fertilizers for wheat followed the order of selenate>selenite, EDTA-chelated selenium>selenium powder, fly ash, and selenium-enriched straw. There was no significant difference between the selenium powder, fly ash, and selenium-enriched straw treatments and the CK treatment. Selenium was more easily transferred to and accumulated in the stems and leaves of wheat after the application of selenate, whereas selenium was more easily transferred to and accumulated in grains after the application of selenite and EDTA-chelated selenium.

Leaf metabolic influence of glyphosate and nanotubes on the Arabidopsis thaliana phyllosphere.

Chemical exposure can indirectly affect leaf microbiota communities, but the mechanism driving this phenomenon remains largely unknown. Results revealed that the co-exposure of glyphosate and multi-carbon nanotubes (CNTs) caused a synergistic inhibitory effect on the growth and metabolism of Arabidopsis thaliana shoots. However, only a slight inhibitory effect was induced by nanotubes or glyphosate alone at the tested concentrations. Several intermediate metabolites of nitrogen metabolism and fatty acid synthesis pathways were upregulated under the combined treatment, which increased the amount of energy required to alleviate the disruption caused by the combined treatment. Additionally, compared with the two individual treatments, the glyphosate/nanotube combination treatment induced greater fluctuations in the phyllosphere bacterial community members with low abundance (relative abundance (RA) <1%) at both the family and genus levels, and among these bacteria some plant growth promotion and nutrient supplement related bacteria were markable increased. Strikingly, strong correlations between phyllosphere bacterial diversity and metabolites suggested a potential role of leaf metabolism, particularly nitrogen and carbohydrate metabolism, in restricting the range of leaf microbial taxa. These correlations between phyllosphere bacterial diversity and leaf metabolism will improve our understanding of plant-microbe interactions and the extent of their drivers of variation and the underlying causes of variability in bacterial community composition.

Feedback Regulation between Aquatic Microorganisms and the Bloom-Forming Cyanobacterium Microcystis aeruginosa.

The frequency and intensity of cyanobacterial blooms are increasing worldwide. Interactions between toxic cyanobacteria and aquatic microorganisms need to be critically evaluated to understand microbial drivers and modulators of the blooms. In this study, we applied 16S/18S rRNA gene sequencing and metabolomics analyses to measure the microbial community composition and metabolic responses of the cyanobacterium Microcystis aeruginosa in a coculture system receiving dissolved inorganic nitrogen and phosphorus (DIP) close to representative concentrations in Lake Taihu, China. M. aeruginosa secreted alkaline phosphatase using a DIP source produced by moribund and decaying microorganisms when the P source was insufficient. During this process, M. aeruginosa accumulated several intermediates in energy metabolism pathways to provide energy for sustained high growth rates and increased intracellular sugars to enhance its competitive capacity and ability to defend itself against microbial attack. It also produced a variety of toxic substances, including microcystins, to inhibit metabolite formation via energy metabolism pathways of aquatic microorganisms, leading to a negative effect on bacterial and eukaryotic microbial richness and diversity. Overall, compared with the monoculture system, the growth of M. aeruginosa was accelerated in coculture, while the growth of some cooccurring microorganisms was inhibited, with the diversity and richness of eukaryotic microorganisms being more negatively impacted than those of prokaryotic microorganisms. These findings provide valuable information for clarifying how M. aeruginosa can potentially modulate its associations with other microorganisms, with ramifications for its dominance in aquatic ecosystems.IMPORTANCE We measured the microbial community composition and metabolic responses of Microcystis aeruginosa in a microcosm coculture system receiving dissolved inorganic nitrogen and phosphorus (DIP) close to the average concentrations in Lake Taihu. In the coculture system, DIP is depleted and the growth and production of aquatic microorganisms can be stressed by a lack of DIP availability. M. aeruginosa could accelerate its growth via interactions with specific cooccurring microorganisms and the accumulation of several intermediates in energy metabolism-related pathways. Furthermore, M. aeruginosa can decrease the carbohydrate metabolism of cooccurring aquatic microorganisms and thus disrupt microbial activities in the coculture. This also had a negative effect on bacterial and eukaryotic microbial richness and diversity. Microcystin was capable of decreasing the biomass of total phytoplankton in aquatic microcosms. Overall, compared to the monoculture, the growth of total aquatic microorganisms is inhibited, with the diversity and richness of eukaryotic microorganisms being more negatively impacted than those of prokaryotic microorganisms. The only exception is M. aeruginosa in the coculture system, whose growth was accelerated.

Effects of Silicon Application on Uptake of Arsenic and Phosphorus and Formation of Iron Plaque in Rice Seedlings Grown in an Arsenic-Contaminated Soil.

Silicon (Si) plays important roles in improving rice growth and mitigating rice arsenic (As) uptake. In the present study, a pot experiment was carried out to investigate effects of Si application on uptake of As and phosphorus (P) and formation of iron (Fe) plaque on root surface of two rice cultivars (Zhendao 10 and Nanjing 44) grown in a high As-contaminated soil. The results showed that dry weights of shoots and roots for both rice cultivars didn't significantly varied under low Si level, but significantly increased for Zhendao 10, while decreased for Nanjing 44 under high Si level (p < 0.05). As concentrations in shoots and roots of Nanjing 44 significantly decreased for low Si level, while significantly increased for high Si level (p < 0.05). Different from Nanjing 44, effect of Si application on As concentrations in the plants of Zhendao 10 wasn't significant (p > 0.05). Si significantly increased concentrations of P in shoots and roots of both rice cultivars (p < 0.05). However, Si didn't significantly affect formation of Fe plaque on root surface. These results suggest that the effects of Si application on rice growth and As uptake in As-contaminated soils may depend on type of rice cultivar and Si application level. Rice cultivar and Si application rate should be considered when Si application is used to mitigate As accumulation in rice.

Impacts of Small-Scale Industrialized Swine Farming on Local Soil, Water and Crop Qualities in a Hilly Red Soil Region of Subtropical China.

Industrialized small-scale pig farming has been rapidly developed in developing regions such as China and Southeast Asia, but the environmental problems accompanying pig farming have not been fully recognized. This study investigated 168 small-scale pig farms and 29 example pig farms in Yujiang County of China to examine current and potential impacts of pig wastes on soil, water and crop qualities in the hilly red soil region, China. The results indicated that the small-scale pig farms produced considerable annual yields of wastes, with medians of 216, 333 and 773 ton yr-1 per pig farm for manure, urine and washing wastewater, respectively, which has had significant impact on surface water quality. Taking NH4⁺-N, total nitrogen (TN) or total phosphorus (TP) as a criterion to judge water quality, the proportions of Class III and below Class III waters in the local surface waters were 66.2%, 78.7% and 72.5%. The well water (shallow groundwater) quality near these pig farms met the water quality standards by a wide margin. The annual output of pollutants from pig farms was the most important factor correlated with the nutrients and heavy metals in soils, and the relationship can be described by a linear equation. The impact on croplands was marked by the excessive accumulation of available phosphorus and heavy metals such as Cu and Zn. For crop safety, the over-limit ratio of Zn in vegetable samples reached 60%, other heavy metals in vegetable and rice samples tested met the food safety standard at present.

Differential responses of soil nematode community to pig manure application levels in Ferric Acrisols.

Excessive pig manure application probably degrades arable soil quality in some intensive pig farming areas. The responses of the nematode community to dosages of pig manure were investigated in Ferric Acrisols under 3-season peanut monoculture. Varying dosages of manure (1.75, 3.5, 7, 14 and 28 t·ha-1·yr-1) in combination with chemical fertilizer were applied to field plots, and chemical fertilizer alone was also applied as a control. With increasing manure application, the abundance of bacterivores and omnivores-predators increased, the abundance of plant parasites decreased, and fungivores abundance exhibited hump-shaped variation. Simpson diversity index and plant parasite index/maturity index of the nematode communities increased to a maximum level at a manure application rate of 3.5 t·ha-1·yr-1 and then sharply decreased. The changes in the soil nematode community were further determined to be correlated with chemical properties; available phosphorus had the strongest quadratic correlation with the two indices, implying that available phosphorus had a better indicative effect than other soil properties to nematode community. Available phosphorus in soil was deduced from 49 to 64 mg·kg-1 with the best nematode communities. Our results emphasized the importance of regular applications of manure in agriculture field to balance nematode diversity and build healthy agro-ecosystems.

[Implantation of calcium phosphate cement/Danshen drug delivery system for avascular necrosis of femoral head].

OBJECTIVE: To introduce a new method using calcium phosphate cement/Danshen drug delivery system for avascular necrosis of femoral head and to evaluate its clinical outcome. METHODS: From May 2000 to June 2005, 48 patients (54 hips) with avascular necrosis of femoral head were treated with calcium phosphate cement/Danshen drug delivery system implantation in the involved femoral head. There were 32 males (36 hips) and 16 females (18 hips) with an average age of 38.7 years (26-62 years). Twenty-one cases had the history of drinking or smoking, 15 cases had the history of receivihg hormonotherapy and 2 had the history of injury in hip joint. The disease course was 2-32 months. According to standard of Association Research Circulation Osseous (ARCO) staging, 9 hips were classified as stage I, 31 as stage II and 14 as stage III The operation consisted of removal of necrotic bone under weight-loading cartilage and the implantation of calcium phosphate cement/Danshen drug delivery system, all manipulations were done through a bone tunnel in trochanter. The function of hip joint were evaluated and X-ray films were taken pre- and post-operatively. RESULTS: No phlebothrombosis of leg and foreign body action occurred in all cases, and incision healed by first intention. The postoperative follow-up averaged 42.5 months, ranging from 22 to 73 months. According to the evaluation criterion of Dandong 1995 for adult avascular necrosis of femoral head, the results were excellent in 33 hips, good in 17, fair in 3 and poor in 1, the excellent and good rate was 92.6%. CONCLUSION: This method is relatively simple with less invasion, it not only improves the microcirculation of femoral head by local application of traditional Chinese medicine, but also provide mechanic buttress in the weight-loaded area, which is beneficial to repair and reconstruction of femoral head. It may be a choice of minimally invasion surgery for femoral head necrosis.