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 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.

Hydrogen sulfide and nitric oxide regulate the adaptation to iron deficiency through affecting Fe homeostasis and thiol redox modification in Glycine max seedlings.

Iron (Fe) is a vital microelement required for the growth and development of plants. Hydrogen sulfide (H2S) and nitric oxide (NO), as messenger molecules, participated in the regulation of plant physiological processes. Here, we studied the interaction effects of H2S and NO on the adaptation to Fe deficiency in Glycine max L. Physiological, biochemical and molecular approaches were conducted to analyze the role of H2S and NO in regulating the adaptation to Fe deficiency in soybean. We found that H2S and NO had obvious rescuing function on the Fe deficiency-induced the plant growth inhibition, which was significantly correlated with the increase in Fe content in the leaves, stems, and roots of soybean. Meanwhile, H+-flux, ferric chelate reductase (FCR) activity, and root apoplast Fe content were significantly affected by H2S and NO. Under Fe deficiency conditions NO and H2S regulated the expression of genes related to Fe homeostasis. Moreover, photosynthesis (Pn) and photosystem II (PSII) efficiency were enhanced by H2S and NO, and thiol redox modification was important for regulating the adaptation of Fe deficiency. The aforementioned affirmative influences caused by H2S and NO were also totally reversed by cPTIO (a NO scavenger). Our results suggested that H2S might act upstream of NO in response to Fe deficiency by affecting the Fe homeostasis enzyme activities and gene expression, and by promoting Fe accumulation in plant tissues as well as by enhancing thiol redox modification and photosynthesis in soybean plants.

The Lactobacillus gasseri G098 Strain Mitigates Symptoms of DSS-Induced Inflammatory Bowel Disease in Mice.

Inflammatory bowel disease (IBD) is a recurring inflammatory disease of the gastrointestinal tract with unclear etiology, but it is thought to be related to factors like immune abnormalities and gut microbial dysbiosis. Probiotics can regulate host immunity and gut microbiota; thus, we investigated the alleviation effect and mechanism of the strain Lactobacillus gasseri G098 (G098) on dextran sodium sulfate (DSS)-induced colitis in mice. Three groups of mice (n = 8 per group) were included: normal control (NC), DSS-induced colitis mice (DSS), and colitis mice given strain (G098). Our results showed that administering G098 effectively reversed DSS-induced colitis-associated symptoms (mitigating weight loss, reducing disease activity index and pathology scores; p < 0.05 in all cases) and prevented DSS-induced mortality (62.5% in DSS group; 100% in G098 group). The mortality rate and symptom improvement by G098 administration was accompanied by a healthier serum cytokine balance (significant decreases in serum pro-inflammatory factors, interleukin (IL)-6 [p < 0.05], IL-1ß [p < 0.01], and tumor necrosis factor (TNF)-α [p < 0.001], and significant increase in the serum anti-inflammatory factor IL-13 [p < 0.01], compared with DSS group) and gut microbiome modulation (characterized by a higher gut microbiota diversity [p < 0.05], significantly more Firmicutes and Lachnoclostridium [p < 0.05], significantly fewer Bacteroidetes [p < 0.05], and significant higher gene abundances of sugar degradation-related pathways [p < 0.05], compared with DSS-treated group). Taken altogether, our results suggested that G098 intake could mitigate DSS-induced colitis through modulating host immunity and gut microbiome, and strain treatment is a promising strategy for managing IBD.

[The study of combining high-risk human papillomavirus types checking and cytologic test in the screening of cervical lesions].

OBJECTIVE: To study the relationship between thinprep cytologic test and the types of human papilloma virus (HPV) infection in cervical precancerous lesion screening. METHODS: To perform high-risk HPV types test in 1375 samples. Choose 256 positive samples to take thinprep cytologic test (TCT) and directed biopsies under colposcopy. Adopting two-channels real time PCR to genotype and quantify eight high risk HPV DNA (high risk types: HPV 16, 18, 45, 31; intermediate risk types: HPV 33, 52, 58, 67). RESULTS: There are 256 positive samples in High risk HPV DNA test (18.62%). WNL rate for TCT is 16.41% (42/256), ASCUS and above rate for TCT is 83.59% (214/256). There is no statistically significant difference in the viral loads of HPV infection rate between the TCT negative patients and positive patients (P > 0.5). Positive correspondence rate for TCT and biopsy are 92.86% (39/42), 81.36% (48/59), 85.19% (23/27) and 9/10. CONCLUSION: High-risk HPV types checking combined with TCT and biopsy can raise positive rate significantly. It should be used as a reliable method for early diagnosis in cervical cancer and CIN screening.