An agroecological structure model of compost-soil-plant interactions for sustainable organic farming.

Compost is used worldwide as a soil conditioner for crops, but its functions have still been explored. Here, the omics profiles of carrots were investigated, as a root vegetable plant model, in a field amended with compost fermented with thermophilic Bacillaceae for growth and quality indices. Exposure to compost significantly increased the productivity, antioxidant activity, color, and taste of the carrot root and altered the soil bacterial composition with the levels of characteristic metabolites of the leaf, root, and soil. Based on the data, structural equation modeling (SEM) estimated that amino acids, antioxidant activity, flavonoids and/or carotenoids in plants were optimally linked by exposure to compost. The SEM of the soil estimated that the genus Paenibacillus and nitrogen compounds were optimally involved during exposure. These estimates did not show a contradiction between the whole genomic analysis of compost-derived Paenibacillus isolates and the bioactivity data, inferring the presence of a complex cascade of plant growth-promoting effects and modulation of the nitrogen cycle by the compost itself. These observations have provided information on the qualitative indicators of compost in complex soil-plant interactions and offer a new perspective for chemically independent sustainable agriculture through the efficient use of natural nitrogen.

Computational estimation of sediment symbiotic bacterial structures of seagrasses overgrowing downstream of onshore aquaculture.

Coastal seagrass meadows are essential in blue carbon and aquatic ecosystem services. However, this ecosystem has suffered severe eutrophication and destruction due to the expansion of aquaculture. Therefore, methods for the flourishing of seagrass are still being explored. Here, data from 49 public coastal surveys on the distribution of seagrass and seaweed around the onshore aquaculture facilities are revalidated, and an exceptional area where the seagrass Zostera marina thrives was found near the shore downstream of the onshore aquaculture facility. To evaluate the characteristics of the sediment for growing seagrass, physicochemical properties and bacterial ecological evaluations of the sediment were conducted. Evaluation of chemical properties in seagrass sediments confirmed a significant increase in total carbon and a decrease in zinc content. Association analysis and linear discriminant analysis refined bacterial candidates specified in seagrass overgrown- and nonovergrown-sediment. Energy landscape analysis indicated that the symbiotic bacterial groups of seagrass sediment were strongly affected by the distance close to the seagrass-growing aquaculture facility despite their bacterial population appearing to fluctuate seasonally. The bacterial population there showed an apparent decrease in the pathogen candidates belonging to the order Flavobacteriales. Moreover, structure equation modeling and a linear non-Gaussian acyclic model based on the machine learning data estimated an optimal sediment symbiotic bacterial group candidate for seagrass growth as follows: the Lachnospiraceae and Ruminococcaceae families as gut-inhabitant bacteria, Rhodobacteraceae as photosynthetic bacteria, and Desulfobulbaceae as cable bacteria modulating oxygen or nitrate reduction and oxidation of sulfide. These observations confer a novel perspective on the sediment symbiotic bacterial structures critical for blue carbon and low-pathogenic marine ecosystems in aquaculture.

Noninvasive fecal metabolic profiling for the evaluation of characteristics of thermostable lactic acid bacteria, Weizmannia coagulans SANK70258, for broiler chickens.

Weizmannia coagulans SANK70258 is a spore-forming thermostable lactic acid bacterium and an effective probiotic for the growth of livestock animals, but its growth-promoting mechanism remains unclear. Here, the composition of fecal metabolites in broilers continuously administered with W. coagulans SANK70258 was assessed under a regular program with antibiotics, which was transiently given for 6 days after birth. Oral administration of W. coagulans to broiler chicks tended to increase the average daily gain of body weights thereafter. The composition of fecal metabolites in the early chick stage (day 10 after birth) was dramatically altered by the continuous exposure. The levels of short-chain fatty acids (SCFAs) propionate and butyrate markedly increased, while those of acetate, one of the SCFAs, and lactate were reduced. Simultaneously, arabitol, fructose, mannitol, and erythritol, which are carbohydrates as substrates for gut microbes to produce SCFAs, also increased along with altered correlation. Correlation network analyses classified the modularity clusters (|r| > 0.7) among carbohydrates, SCFAs, lactate, amino acids, and the other metabolites under the two conditions. The characteristic diversities by the exposure were visualized beyond the perspective associated with differences in metabolite concentrations. Further, enrichment pathway analyses showed that metabolic composition related to biosynthesis and/or metabolism for SCFAs, amino acids, and energy were activated. Thus, these observations suggest that W. coagulans SANK70258 dramatically modulates the gut metabolism of the broiler chicks, and the metabolomics profiles during the early chick stages may be associated with growth promotion.

A potential network structure of symbiotic bacteria involved in carbon and nitrogen metabolism of wood-utilizing insect larvae.

Effective biological utilization of wood biomass is necessary worldwide. Since several insect larvae can use wood biomass as a nutrient source, studies on their digestive microbial structures are expected to reveal a novel rule underlying wood biomass processing. Here, structural inferences for inhabitant bacteria involved in carbon and nitrogen metabolism for beetle larvae, an insect model, were performed to explore the potential rules. Bacterial analysis of larval feces showed enrichment of the phyla Chroloflexi, Gemmatimonadetes, and Planctomycetes, and the genera Bradyrhizobium, Chonella, Corallococcus, Gemmata, Hyphomicrobium, Lutibacterium, Paenibacillus, and Rhodoplanes, as bacteria potential involved in plant growth promotion, nitrogen cycle modulation, and/or environmental protection. The fecal abundances of these bacteria were not necessarily positively correlated with their abundances in the habitat, indicating that they were selectively enriched in the feces of the larvae. Correlation and association analyses predicted that common fecal bacteria might affect carbon and nitrogen metabolism. Based on these hypotheses, structural equation modeling (SEM) statistically estimated that inhabitant bacterial groups involved in carbon and nitrogen metabolism were composed of the phylum Gemmatimonadetes and Planctomycetes, and the genera Bradyrhizobium, Corallococcus, Gemmata, and Paenibacillus, which were among the fecal-enriched bacteria. Nevertheless, the selected common bacteria, i.e., the phyla Acidobacteria, Armatimonadetes, and Bacteroidetes and the genera Candidatus Solibacter, Devosia, Fimbriimonas, Gemmatimonas Opitutus, Sphingobium, and Methanobacterium, were necessary to obtain good fit indices in the SEM. In addition, the composition of the bacterial groups differed depending upon metabolic targets, carbon and nitrogen, and their stable isotopes, δ13C and δ15N, respectively. Thus, the statistically derived causal structural models highlighted that the larval fecal-enriched bacteria and common symbiotic bacteria might selectively play a role in wood biomass carbon and nitrogen metabolism. This information could confer a new perspective that helps us use wood biomass more efficiently and might stimulate innovation in environmental industries in the future.

Transcardiac increase in tumor necrosis factor-alpha and left ventricular end-diastolic volume in patients with dilated cardiomyopathy.

BACKGROUND: It remains unclear whether tumor necrosis factor (TNF)-alpha and interleukin-6 (IL-6) are secreted from the failing heart and whether there is a relationship between the transcardiac gradients of these cytokines and left ventricular (LV) remodeling. AIMS: This study evaluated the relationship between transcardiac gradients of cytokines and LV volume and function in congestive heart failure patients with dilated cardiomyopathy (DCM). METHODS AND RESULTS: We measured the plasma levels of TNF-alpha and IL-6 in the aortic root (Ao) and the coronary sinus (CS) in 60 patients with DCM. There was no difference in plasma IL-6 between the Ao and the CS. However, the plasma TNF-alpha level was significantly higher in the CS than that in the Ao. There was a significant correlation between the transcardiac gradient of plasma TNF-alpha and the LV end-diastolic volume index (LVEDVI) and LV ejection fraction. According to stepwise multivariate analyses, the transcardiac increase of TNF-alpha showed an independent and significantly positive relationship with a large LVEDVI. CONCLUSIONS: These results indicate that the elevated plasma TNF-alpha is partly derived from the failing heart in patients with DCM and that TNF-alpha plays a potential role in structural LV remodeling in patients with DCM.

Immediate administration of mineralocorticoid receptor antagonist spironolactone prevents post-infarct left ventricular remodeling associated with suppression of a marker of myocardial collagen synthesis in patients with first anterior acute myocardial infarction.

BACKGROUND: Aldosterone (ALD) has been shown to stimulate cardiac collagen synthesis and fibroblast proliferation via activation of local mineralocorticoid receptors. In patients with acute myocardial infarction, we demonstrated that ALD was extracted through the infarct heart and extracting ALD-stimulated post-infarct left ventricular (LV) remodeling. METHODS AND RESULTS: To evaluate the effect of mineralocorticoid receptor antagonist (MRA) spironolactone on post-infarct LV remodeling, 134 patients with first anterior acute myocardial infarction were randomly divided into the MRA (n=65) or non-MRA (n=69) groups after revascularization. All patients were administered angiotensin-converting enzyme (ACE) inhibitor and study drug just after revascularization. Left ventriculography with contrast medium was performed at the acute stage and after 1 month to evaluate LV remodeling. ALD was measured at aortic root and coronary sinus. There was no difference in the baseline characteristics including infarct size and LV performance between the two groups. However, LV ejection fraction was significantly improved in the MRA group compared with that in the non-MRA group (46.0+/-0.6% to 53.2+/-0.8% versus 46.5+/-0.8% to 51.0+/-0.8%, Pinteraction=0.012). LV end-diastolic volume index was significantly suppressed in the MRA group compared with that in non-MRA group (86.5+/-1.0 to 90.6+/-2.4 versus 87.5+/-1.3 to 106.8+/-3.5 mL/m2, Pinteraction=0.002). Transcardiac extraction of ALD through the heart was significantly suppressed in the MRA group (Pinteraction=0.001), and plasma procollagen type III aminoterminal peptide level, a biochemical marker of fibrosis, was significant lower in the MRA group compared with the non-MRA group (Pinteraction=0.002). CONCLUSIONS: These findings indicate that MRA combined with ACE inhibitor can prevent post-infarct LV remodeling better than ACE inhibitor alone in association with the suppression of a marker of collagen synthesis.

Transcardiac gradient of aldosterone before and after spironolactone in patients with congestive heart failure.

To evaluate the transcardiac extraction of aldosterone before and after spironolactone administration to patients with congestive heart failure, we measured the plasma aldosterone in the aortic root and the coronary sinus in eight congestive heart failure patients with dilated cardiomyopathy. The plasma aldosterone level was significantly lower in the coronary sinus than in the aortic root before spironolactone administration (87.5 +/- 16 versus 62.2 +/- 11 pg/ml, p = 0.01). After chronic treatment with spironolactone, there was no significant difference in the aldosterone level between the aortic root and the coronary sinus (151 +/- 49 versus 148 +/- 48 pg/ml), and the transcardiac gradient of aldosterone (aortic root to coronary sinus) was significantly decreased (25.3 +/- 7.3 versus 3.1 +/- 4.5 pg/ml, p = 0.046). These results indicate that plasma aldosterone is extracted through the heart in congestive heart failure patients with dilated cardiomyopathy, and that spironolactone inhibits the transcardiac extraction of aldosterone in congestive heart failure patients. This suggests that spironolactone blocks the effects of aldosterone on the failing heart in congestive heart failure patients with dilated cardiomyopathy.

Effects of long-acting calcium channel antagonists on neurohumoral factors: comparison of nifedipine coat-core with amlodipine.

Calcium channel antagonists can induce sympathetic hyperactivity, leading to a poor prognosis for hypertensive patients. Nifedipine formulations that allow once-daily administration are now available for use in clinical practice. To compare the effects of nifedipine with those of amlodipine, we studied 36 essential hypertensive patients. Those who had been administered nifedipine sustained-release were treated with amlodipine in place of nifedipine sustained-release, and those who had been administered amlodipine were treated with nifedipine coat-core in place of amlodipine. Substitution of nifedipine sustained-release by amlodipine had no significant effect on hypertensive symptoms. However, the plasma levels of norepinephrine, renin, and aldosterone were significantly lower (p < 0.001-0.05) in patients taking amlodipine in place of nifedipine sustained-release. Substitution of amlodipine by nifedipine coat-core again had no significant effect on hypertensive symptoms. However, the plasma levels of norepinephrine, renin, and aldosterone did not change significantly after the substitution. These findings indicate that, at the effective anti-hypertensive concentrations of nifedipine coat-core and amlodipine, nifedipine coat-core may not increase sympathetic nerve activity as is observed with amlodipine. The results also suggest that the duration of action of nifedipine formulations is an important determinant for nifedipine-induced hyperactivity in the reflex sympathetic nerve and the renin-angiotensin systems.

Effect of an angiotensin II type 1 receptor blocker, valsartan, on neurohumoral factors in patients with hypertension: comparison with a long-acting calcium channel antagonist, amlodipine.

This study compared the effects of amlodipine and valsartan on the sympathetic nervous system, the renin-angiotensin-aldosterone system, and brain natriuretic peptide, which are considered important parameters of the long-term prognosis. Seventy-three elderly patients, who had received antihypertensive treatment for more than 6 months with amlodipine, participated in this study. They were randomized to the V group (n = 36) and switched to valsartan from amlodipine, or to the A group (n = 37), which continued treatment with amlodipine. The dose of valsartan was set as that which controlled the blood pressure to the same extent as before switching. Blood samples were measured before and after 6 months of therapy. Data were analyzed by two-way analysis of variance with the Newman-Keuls test. In the V group, norepinephrine (from 597.0 +/- 52.9 to 475 +/- 43.8 pg/ml, p < 0.05) and aldosterone (from 74.5 +/- 7.0 to 53.9 +/- 5.3 pg/ml, p < 0.001) were decreased significantly after 6 months, although norepinephrine and aldosterone levels were unchanged in the A group. However, brain natriuretic peptide did not show a difference between the two groups. These findings suggested that valsartan is probably superior to amlodipine with respect to less activation of the sympathetic nervous system and preventing upregulation of the renin-angiotensin-aldosterone system.