Interactions between hydrogen sulphide and rhizobia modulate the physiological and metabolism process during water deficiency-induced oxidative defense in soybean.

Hydrogen sulphide (H2 S), a new gas signal molecule, participates in the regulation of various abiotic stresses in plants. However, how the tandem working of H2 S and rhizobia affects the adaptation of soybean to water deficiency is still unclear. In this study, we investigated the adaptation mechanism of H2 S and rhizobia in soybean to water deficiency. Our results revealed that H2 S and rhizobia jointly enhanced the leaf chlorophyll content and relative water content in plants, and caused an increase in the biomass of soybean seedlings under water deficiency. Besides, in the absence of water, H2 S enhanced the biomass by affecting the number of nodules and nitrogenase activity during vegetative growth. The expression of nodulation marker genes including early nodulin 40 (GmENOD40), ERF required for nodulation (GmERN) and nodulation inception genes (GmNIN1a, GmNIN2a and GmNIN2b) were upregulated by H2 S and rhizobia in the nodules. Moreover, the combined effect of H2 S and rhizobia was proved to affect the enzyme activities and gene expression level of antioxidants, as well as osmotic protective substance content and related gene expression levels under water deficiency in soybean seedlings. In addition, the metabolomic results suggested that the combined effect of H2 S and rhizobia remarkably promoted the contents of lipids and lipid-like molecules. Our results indicated that H2 S and rhizobia synergistically reduced the oxidative damage caused by water deficiency through increasing the accumulation of metabolites and strengthening the plant antioxidant capacity.

Hydrogen sulphide alleviates iron deficiency by promoting iron availability and plant hormone levels in Glycine max seedlings.

BACKGROUND: Hydrogen sulphide (H2S) is involved in regulating physiological processes in plants. We investigated how H2S ameliorates iron (Fe) deficiency in soybean (Glycine max L.) seedlings. Multidisciplinary approaches including physiological, biochemical and molecular, and transcriptome methods were used to investigate the H2S role in regulating Fe availability in soybean seedlings. RESULTS: Our results showed that H2S completely prevented leaf interveinal chlorosis and caused an increase in soybean seedling biomass under Fe deficiency conditions. Moreover, H2S decreased the amount of root-bound apoplastic Fe and increased the Fe content in leaves and roots by regulating the ferric-chelate reductase (FCR) activities and Fe homeostasis- and sulphur metabolism-related gene expression levels, thereby promoting photosynthesis in soybean seedlings. In addition, H2S changed the plant hormone concentrations by modulating plant hormone-related gene expression abundances in soybean seedlings grown in Fe-deficient solution. Furthermore, organic acid biosynthesis and related genes expression also played a vital role in modulating the H2S-mediated alleviation of Fe deficiency in soybean seedlings. CONCLUSION: Our results indicated that Fe deficiency was alleviated by H2S through enhancement of Fe acquisition and assimilation, thereby regulating plant hormones and organic acid synthesis in plants.

Hydrogen sulfide and rhizobia synergistically regulate nitrogen (N) assimilation and remobilization during N deficiency-induced senescence in soybean.

Hydrogen sulfide (H2 S) is emerging as an important signalling molecule that regulates plant growth and abiotic stress responses. However, the roles of H2 S in symbiotic nitrogen (N) assimilation and remobilization have not been characterized. Therefore, we examined how H2 S influences the soybean (Glycine max)/rhizobia interaction in terms of symbiotic N fixation and mobilization during N deficiency-induced senescence. H2 S enhanced biomass accumulation and delayed leaf senescence through effects on nodule numbers, leaf chlorophyll contents, leaf N resorption efficiency, and the N contents in different tissues. Moreover, grain numbers and yield were regulated by H2 S and rhizobia, together with N accumulation in the organs, and N use efficiency. The synergistic effects of H2 S and rhizobia were also demonstrated by effects on the enzyme activities, protein abundances, and gene expressions associated with N metabolism, and senescence-associated genes (SAGs) expression in soybeans grown under conditions of N deficiency. Taken together, these results show that H2 S and rhizobia accelerate N assimilation and remobilization by regulation of the expression of SAGs during N deficiency-induced senescence. Thus, H2 S enhances the vegetative and reproductive growth of soybean, presumably through interactions with rhizobia under conditions of N deficiency.

Expression analysis of microRNAs and their target genes during experimental diabetic renal lesions in rats administered with ginsenoside Rb1 and trigonelline.

Purpose: To appraise the curative effect of ginsenoside Rb1 and trigonelline in diabetic nephropathy and to analyze the expression analysis of microRNAs and their target genes during experimental diabetic renal lesions in rats. Methods: Wistar rats were made diabetic by intraperitoneal injection of 55 mg/kg streptozotocin. According to their fasting blood glucose values and initial body weight, diabetic rats were assigned to specific groups and treated as follows: DN group (tap water, n = 10), A group (ginsenoside Rb1, 40 mg/kg, n = 10), B group (trigonelline, 20 mg/kg, n = 10) and the C group (ginsenoside Rb1 and trigonelline, 60 mg/kg, m(ginsenoside Rb1) : m (trigonelline) = 2:1, n = 10). The control group was treated with tap water (n = 10). All rats were gavaged with drugs or tap water once daily for 12 weeks. Results: Renal dysfunction, oxidative stress, and pathological alteration were significantly alleviated by a combination of ginsenoside Rb1 and trigonellin (C group). Some miRNAs were expressed differentially in Con, DN, A and C groups. Results of immunohistochemistry and western blotting showed that Wnt and ß-catenin were expressed differentially in Con, DN, and C groups. Conclusion: Ginsenoside Rb1 and trigonelline could prevent the development of diabetic renal lesions by regulating the expression of miR-3550 and further associating with the Wnt/ß-catenin signaling.

Rapid isolation of extracellular vesicles using covalent organic frameworks combined with microfluidic technique.

Extracellular vesicles (EVs) are nano-sized lipid-membrane vesicles involved in intercellular communication and reflecting the physiological and pathological processes of their parental cells. Rapid isolation of EVs with low cost is an essential precondition for downstream function exploration and clinical applications. In this work, we designed a novel EVs isolation device based on the boronated organic framework (BOF) coated recyclable microfluidic chip (named EVs-BD) to separate EVs from cell culture media. Using a reactive oxygen species responsive phenylboronic ester compound, the highly porous BOF with a pore size in the range of 10-300 nm was prepared by crosslinking γ-cyclodextrin metal-organic frameworks. A mussel-inspired polydopamine (PDA)/polyethyleneimine (PEI) coating was employed to pattern BOF on the PDMS substrate of microfluidic channels. The EVs-BD was demonstrated to offer distinct advantages over the traditional ultracentrifugation method, such as operation simplicity and safety, reduced time and expense, and low expertize requirements. All things considered, a novel approach of EV acquisition has been successfully developed, which can be customized easily to meet the requirements of various EV-relevant research.

Glycyrrhetinic acid loaded in milk-derived extracellular vesicles for inhalation therapy of idiopathic pulmonary fibrosis.

Idiopathic pulmonary fibrosis (IPF) is a chronic, progressive, and life-threatening lung disease for which treatment options are limited. Glycyrrhetinic acid (GA) is a triterpenoid with multiple biological effects, such as anti-inflammatory and anti-fibrotic properties. Herein, inhalable milk-derived extracellular vesicles (mEVs) encapsulating GA (mEVs@GA) were screened and evaluated for IPF treatment. The results indicated that the loading efficiency of GA in mEVs@GA was 8.65%. Therapeutic effects of inhalable mEVs@GA were investigated in vitro and in vivo. The mEVs@GA demonstrated superior anti-inflammatory effects on LPS-stimulated MHS cells. Furthermore, repeated noninvasive inhalation delivery of mEVs@GA in bleomycin-induced IPF mice could decrease the levels of transforming growth factors ß1 (TGF-ß1), Smad3 and inflammatory cytokines IL-6, IL-1ß and TNF-α. The mEVs@GA effectively diminished the development of fibrosis and improved pulmonary function in the IPF mice model at a quarter of the dose compared with the pirfenidone oral administration group. Additionally, compared to pirfenidone-loaded mEVs, mEVs@GA demonstrated superior efficacy at the same drug concentration in the pharmacodynamic study. Overall, inhaled mEVs@GA have the potential to serve as an effective therapeutic option in the treatment of IPF.

Effects of pleiotrophin (PTN) on the FAK inhibitor Y15 in breast cancer cells.

Overexpression of PTN (Pleiotrophin) in breast cancer cells stimulates breast cell proliferation and anti-apoptosis via the FAK/Src signaling pathway.1,2,4,5-Benzenetetramine tetrahydrochloride (C6H14Cl4N4) known as Y15 is an inhibitor that specifically blocks phosphorylation of Y397-FAK and total FAK phosphorylation. The exogenous PTN protein was induced to be expressed by a prokaryotic expression strain. The addition of PTN protein decreased the sensitivity of breast cancer cells to Y15, as shown by both MTT and flow cytometry assays. Breast cancer cells transfected with sh-RNA knockdown PTN were analyzed by real-time fluorescence quantitative PCR reaction (RT-PCR) and protein immunoblotting 24 h after transfection. MTT assay data showed a significant increase in the IC50 value of Y15 against breast cancer cells in the presence of PTN protein. Flow cytometry data confirmed the dose-dependent anti-apoptotic effect of PTN protein in Y15-treated breast cancer cells. After transfection with sh-RNA, Y15 further inhibited the FAK pathway, greatly reducing cell survival and promoting apoptosis. Western blotting analysis showed that knockdown of PTN protein with sh-RNA resulted in increased apoptosis and elevated levels of apoptotic proteins, such as cleaved PARP and cleaved caspase-3 in Y15-induced breast cancer cells. Finally, it was hypothesized that PTN and Y15 were associated with a significant increase in the IC50 value of PTN and Y15 in breast cancer cells by western blotting analysis. It was hypothesized that PTN and Y15 regulate the proliferation and apoptosis of breast cancer cells through the AKT/PI3K pathway. The results demonstrated that PTN affects the sensitivity of the kinase inhibitor Y15, and PTN silencing and Y15 may inhibit the survival of breast cancer cells through the AKT/PI3K pathway, which lays the foundation for subsequent in-depth research on the clinical treatment of breast cancer.

Controlled release of vitamin A palmitate from crosslinked cyclodextrin organic framework for dry eye disease therapy.

Controlled release drug delivery systems of eye drops are a promising ophthalmic therapy with advantages of good patient compliance and low irritation. However, the lack of a suitable drug carrier for ophthalmic use limits the development of the aforementioned system. Herein, the crosslinked cyclodextrin organic framework (COF) with a cubic porous structure and a uniform particle size was synthesized and applied to solidify vitamin A palmitate (VAP) by using the solvent-free method. The VAP@COF suspension eye drops were formulated by screening co-solvents, suspending agents, and stabilizing agents to achieve a homogeneous state and improve stability. According to the in vitro release study, the VAP@COF suspension exhibited a controlled release of VAP within 12 h. Both the ex vivo corneal contact angle and in vivo fluorescence tracking indicated that the VAP@COF suspension prolonged the VAP residence time on the ocular surface. This suspension accelerated the recovery of the dry eye disease (DED) model in New Zealand rabbits. Furthermore, the suspension was non-cytotoxic to human corneal epithelial cells and non-irritation to rabbit eyes. In summary, the particulate COF is an eye-acceptable novel carrier that sustains release and prolongs the VAP residence time on the ocular surface for DED treatment.

Purification of gamma-cyclodextrin via selective coordination with potassium ions to form metal-organic frameworks.

Efficient purification of gamma-cyclodextrin (γ-CD) is always challenging due to its structural similarity to other CDs and low crystallinity in water. In addressing this issue, an approach was proposed based on the formation mechanism of cyclodextrin metal-organic frameworks (CD-MOFs). This method involved the selective coordination of CDs mixture with potassium ions in water, facilitated by ethanol-induced crystallization, leading to the purification of γ-CD. The results showed that potassium ions enhanced γ-CD crystallization, and ethanol was crucial to selectively coordinating potassium ions with γ-CD. The characterizations revealed that the resulting CD-MOFs exhibited a small particle size, high surface area, and high thermal stability, and was identical to γ-CD-MOF, further indicating the final γ-CD with high purity. The separation factors of γ-CD/α-CD and γ-CD/ß-CD were 309 and 260, respectively. Moreover, this method was validated through its application to the industrial enzymatic CDs mixture. The purification of γ-CD could achieve 99.99 ± 0.01 % after four crystallization cycles. Therefore, selectively coordinating with potassium ions to form MOFs provided a valuable reference for the purification of γ-CD and even the direct synthesis of γ-CD-MOF from CDs mixture. This advancement will also benefit the future production and application of γ-CD.

Unravelling calcium-alleviated aluminium toxicity in Arabidopsis thaliana: Insights into regulatory mechanisms using proteomics.

Aluminium (Al) toxicity is a major limiting factor for plant productivity in acidic soils. Calcium (Ca) is an essential element and participates in various physiological responses to environmental stress. Here, the aim of this work was to study the role of exogenous Ca in alleviating Al toxicity in Arabidopsis thaliana. For that we used the methods of physiology and proteomics. Results showed that Ca alleviated Al-induced growth inhibition and decreased Al accumulation. Proteomic analyses showed that 75 differentially expressed protein spots, including those related to organic acid metabolism, cell wall components, cellular transport, signal transduction and antioxidant activity, transcription and protein metabolism were identified during the response of Arabidopsis to Ca alleviated Al toxicity. Ca regulated tricarboxylic acid (TCA) cycle-related protein abundances and affected organic acid concentrations and related enzyme activities under Al stress. Vacuolar and mitochondrion adenosine triphosphate (ATP) synthase, and cell wall component-related proteins played important roles in Ca-alleviated Al toxicity. Ethylene-insensitive 3 (EIN3) participated in Ca-alleviated Al toxicity. Glutathione S-transferase (GST6) and glutathione S-transferase tau 19 (ATGSTU19) were associated with antioxidant activities induced by Ca under Al stress. Our results may contribute to an understanding of the functional mechanism by which Ca alleviates Al stress in plants. SIGNIFICANT: Our results elucidated how Ca alleviate the effects of Al toxicity on the inhibition of plant growth and Al accumulation in plants using the proteomics and physiological methods, which may contribute to a better understanding of the molecular mechanism of Ca alleviation Al stress in plants.