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The expansion of invasive Japanese knotweed s. l. is of particular concern because of its aptitudes to rapidly colonize diverse environments, especially anthropized habitats generally characterized by their pollution with heavy metals. Whether the presence of heavy metals impacts the performance traits of this plant is a central question to better understand its invasive properties, though no controlled approach to assess these effects was yet reported. In this aim, we undertook greenhouse experiments where rhizome fragments of Japanese knotweed s. l. ( Fallopia japonica and Fallopia × bohemica) were grown during 1 and 3 months, in a soil pot artificially polluted or not with heavy metals added in mixture (Cd, Cr, Pb, Zn). Our results showed that (i) the presence of heavy metals delayed rhizome regeneration and induced lowered plant part weights but did not affect plant height after 3 months; (ii) the effect of metals on the metabolic profiles of belowground part extracts was only detectable after 1 month and not after 3 months of growth, though it was possible to highlight the effect of metals independently of time and genotype for root extracts, and torosachrysone seemed to be the most induced compound; and (iii) the hybrid genotype tested was able to accumulate relatively high concentrations of metals, over or close to the highest reported ones for this plant for Cr, Cd and Zn, whereas Pb was not accumulated. These findings evidence that the presence of heavy metals in soil has a low impact on Fallopia sp. overall performance traits during rhizome regeneration, and has a rather stimulating effect on plant growth depending on pollution level. [ABSTRACT FROM AUTHOR]

BACKGROUND: Hypertension is characterized by a maintained high blood pressure leading to cardiac complications such as left ventricular hypertrophy and fibrosis and an increased risk of heart failure and myocardial infarction. This study investigated the cardiac effects of oral administration of Moringa oleifera (MOI) seed powder in spontaneous hypertensive rats (SHR). METHODS: SHR received food containing MOI seed powder (750mg/d, 8 weeks) or normal food. In vivo measurement of hemodynamic parameters by telemetry and cardiac structure and function analysis by echocardiography were performed. Histological studies were performed to determine fibrosis and protein expression. RESULTS: MOI treatment did not modify blood pressure in SHR but reduced nocturnal heart rate and improved cardiac diastolic function (reduction of isovolumetric relaxation time and deceleration time of the E wave, increase of ejection volume and cardiac output compared to nontreated SHR). Left ventricular anterior wall thickness, interseptal thickness on diastole, and relative wall thickness were reduced after MOI treatment. Furthermore, we found a significant reduction of fibrosis in the left ventricle of MOI-treated SHR. This antihypertrophic and antifibrotic effect of MOI was associated with increased expression of peroxisome proliferator-activated receptor (PPAR)-α andδ, reduced cardiac triglyceride level, and enhanced plasmatic prostacyclins. CONCLUSIONS: Our data show a beneficial effect of MOI on the cardiac structure and function in SHR associated with an upregulation of PPAR-α and δ signaling. This study thus provides scientific rational support for the empirical use of MOI in the traditional Malagasy medicine against cardiac diseases associated with blood pressure overload. [ABSTRACT FROM AUTHOR]

The purpose of this study was to assess the antitumor and immunomodulatory effects of the aqueous extract from Daphne gnidium in mice-bearing melanoma tumor. Balb/C mice were subcutaneously implanted with B16-F10 cells and treated intraperitoneally with the aqueous extract at 200 mg/Kg b.w for 21 days. After euthanization on day 22, the tumors were weighed; lymphocyte proliferation, cytotoxic T lymphocyte (CTL), and natural killer (NK) cell activities were evaluated using the MTT assay. Macrophage phagocytosis was studied by measuring the lysosomal activity. In addition to its potential to inhibit the growth of the transplantable tumor, the aqueous extract remarkably induced splenocyte proliferation and both NK and CTL activities in tumor-bearing mice. The aqueous extract was also seen to have promoted lysosomal activity of host macrophages. [ABSTRACT FROM AUTHOR]

The three primary resistance-nodulation-cell division (RND) efflux pump families (heavy metal efflux [HME], nodulation factor exporter [NFE], and hydrophobe/amphiphile efflux-1 [HAE-1]) are almost exclusively found in Gram-negative bacteria and play a major role in resistance against metals and bacterial biocides, including antibiotics. Despite their significant societal interest, their evolutionary history and environmental functions are poorly understood. Here, we conducted a comprehensive phylogenetic and ecological study of the RND permease, the subunit responsible for the substrate specificity of these efflux pumps. From 920 representative genomes of Gram-negative bacteria, we identified 6205 genes encoding RND permeases with an average of 6.7 genes per genome. The HME family, which is involved in metal resistance, corresponds to a single clade (21.8% of all RND pumps), but the HAE-1 and NFE families had overlapping distributions among clades. We propose to restrict the HAE-1 family to two phylogenetic sister clades, representing 41.8% of all RND pumps and grouping most of the RND pumps involved in multidrug resistance. Metadata associated with genomes, analyses of previously published metagenomes, and quantitative Polymerase Chain Reaction (qPCR) analyses confirmed a significant increase in genes encoding HME permeases in metal-contaminated environments. Interestingly, and possibly related to their role in root colonization, genes encoding HAE-1 permeases were particularly abundant in the rhizosphere. In addition, we found that the genes encoding these HAE-1 permeases are significantly less abundant in marine environments, whereas permeases of a new proposed HAE-4 family are predominant in the genomes of marine strains. These findings emphasize the critical role of the RND pumps in bacterial resistance and adaptation to diverse ecological niches., Competing Interests: None declared., (© The Author(s) 2024. Published by Oxford University Press on behalf of the International Society for Microbial Ecology.)

In the present work, chemical investigation of the aerial parts of Phlomis bovei de Noé an endemic species from Algeria, led to the isolation and identification of seven known compounds including five flavones glycosides: Chrysoeriol 7- O -(3''-( E et Z )- p -coumaroyl)-β-glucoside (1) , terniflorin (apigenin-7- O -(6''- E-p -coumaroyl)glucoside) (3) , apigenin-7- O -(6''-(5'''-methoxy-coumaryl) glucoside (4) , apigenin 7- O -(3″- p -coumaryl) glucoside (5) , hispidulin-7- O -glucuronide (6) and two cinnamic acid derivatives: p -coumaric acid methyl ester ( E et Z ) (2) , chlorogenic acid (7) . Compound 4 is described for the first time in the species bovei de Noé, the genus Phlomis and the Lamiaceae family. Structures elucidation was performed by comprehensive 1D and 2D NMR analyses, mass spectrometry and by comparison with literature data. Some pure compounds and extracts have been evaluated for their antioxidant activities through different methods: DPPH and ABTS assays as well as CUPRAC assay. Genotoxic and antigenotoxic activities of pure compounds were also evaluated in-vitro on Escherichia coli PQ37 cells by the SOS Chromotest.

The effect of plant diversity on aboveground organisms and processes was largely studied but there is still a lack of knowledge regarding the link between plant diversity and soil characteristics. Here, we analyzed the effect of plant identity and diversity on the diversity of extractible soil organic compounds (ESOC) using 87 experimental grassland plots with different levels of plant diversity and based on a pool of over 50 plant species. Two pools of low molecular weight organic compounds, LMW1 and LMW2, were characterized by GC-MS and HPLC-DAD, respectively. These pools include specific organic acids, fatty acids and phenolics, with more organic acids in LMW1 and more phenolics in LMW2. Plant effect on the diversity of LMW1 and LMW2 compounds was strong and weak, respectively. LMW1 richness observed for bare soil was lower than that observed for all planted soils; and the richness of these soil compounds increased twofold when dominant plant species richness increased from 1 to 6. Comparing the richness of LMW1 compounds observed for a range of plant mixtures and for plant monocultures of species present in these mixtures, we showed that plant species richness increases the richness of these ESOC mainly through complementarity effects among plant species associated with contrasted spectra of soil compounds. This could explain previously reported effects of plant diversity on the diversity of soil heterotrophic microorganisms., Competing Interests: The authors have declared that no competing interests exist.

The purpose of this study was to assess the antitumor and immunomodulatory effects of the aqueous extract from Daphne gnidium in mice-bearing melanoma tumor. Balb/C mice were subcutaneously implanted with B16-F10 cells and treated intraperitoneally with the aqueous extract at 200 mg/Kg b.w for 21 days. After euthanization on day 22, the tumors were weighed; lymphocyte proliferation, cytotoxic T lymphocyte (CTL), and natural killer (NK) cell activities were evaluated using the MTT assay. Macrophage phagocytosis was studied by measuring the lysosomal activity. In addition to its potential to inhibit the growth of the transplantable tumor, the aqueous extract remarkably induced splenocyte proliferation and both NK and CTL activities in tumor-bearing mice. The aqueous extract was also seen to have promoted lysosomal activity of host macrophages.