Applying generalized additive models to unravel dynamic changes in anthocyanin biosynthesis in methyl jasmonate elicited grapevine (Vitis vinifera cv. Gamay) cell cultures

Temperature and nutrients alter the relative importance of stochastic and deterministic processes in the coastal macroinvertebrates biodiversity assembly on long-time scales

Macroinvertebrates play a vital role in coastal ecosystems and are an important indicator of ecosystem quality. Both anthropogenic activity and environmental changes may lead to significant changes in the marine macroinvertebrate community. However, the assembly process of benthic biodiversity and its mechanism driven by environmental factors at large scales remains unclear. Here, using the benthic field survey data of 15 years at large spatial and temporal scales from the Yellow Sea Large Marine Ecosystem, we investigated the relative importance of environmental selection, dispersal processes, random-deterministic processes of macroinvertebrates community diversity assembly, and the responses of this relative importance driven by temperature and nutrients. Results showed that the macroinvertebrates community diversity is mainly affected by dispersal. Nitrogen and phosphorus are the most important negative factors among environmental variables, while geographical distance is the main limiting factor of β diversity. Within the range of 0.35-0.70 mg/L of nutrients, increasing nutrient concentration can significantly facilitate the contribution of the decay effect to β diversity. Within the temperature range studied (15.0-18.0°C), both warming and cooling can lead to a greater tendency for species diversity assembly processes to be dominated by deterministic processes. The analysis contributes to a better understanding of the assembly process of the diversity of coastal marine macroinvertebrates communities and how they adapt to global biogeochemical processes.

Phenylpropanoids Following Wounding and Infection of Sweet Sorghum Lines Differing in Responses to Stalk Pathogens

Sweet sorghum (Sorghum bicolor) lines M81-E and Colman were previously shown to differ in responses to Fusarium thapsinum and Macrophomina phaseolina, stalk rot pathogens that can reduce the yields and quality of biomass and extracted sugars. Inoculated tissues were compared for transcriptomic, phenolic metabolite, and enzymatic activity during disease development 3 and 13 days after inoculation (DAI). At 13 DAI, M81-E had shorter mean lesion lengths than Colman when inoculated with either pathogen. Transcripts encoding monolignol biosynthetic and modification enzymes were associated with transcriptional wound (control) responses of both lines at 3 DAI. Monolignol biosynthetic genes were differentially coexpressed with transcriptional activator SbMyb76 in all Colman inoculations, but only following M. phaseolina inoculation in M81-E, suggesting that SbMyb76 is associated with lignin biosynthesis during pathogen responses. In control inoculations, defense-related genes were expressed at higher levels in M81-E than Colman. Line, treatment, and timepoint differences observed in phenolic metabolite and enzyme activities did not account for observed differences in lesions. However, generalized additive models were able to relate metabolites, but not enzyme activities, to lesion length for quantitatively modeling disease progression: in M81-E, but not Colman, sinapic acid levels positively predicted lesion length at 3 DAI when cell wall-bound syringic acid was low, soluble caffeic acid was high, and lactic acid was high, suggesting that sinapic acid may contribute to responses at 3 DAI. These results provide potential gene targets for development of sweet sorghum varieties with increased stalk rot resistance to ensure biomass and sugar quality.

Associations between pyrethroid exposure and serum sex steroid hormones in adults: Findings from a nationally representative sample

BACKGROUND

Pyrethroids have been considered as potential endocrine-disrupting chemicals and have been shown to be associated with endocrine-related health outcomes. However, limited studies directly explored the link between pyrethroid exposure and sex hormones in the general population.

OBJECTIVES

To explore the associations between exposure to pyrethroids and serum sex steroid hormones in adults.

METHODS

We evaluated the cross-sectional associations in 1235 adults aged ≥20 years who had been assigned to the National Health and Nutrition Examination Survey (NHANES) 2013-2014. The urinary concentration of 3-phenoxybenzoic acid (3-PBA) was applied as a biomarker of human pyrethroid exposure levels. Information on sex steroid hormones, including total testosterone (TT), estradiol (E2), and sex hormone-binding globulin (SHBG) in serum were measured. Free androgen index (FAI) and the ratio of TT to E2 (TT/E2) were also calculated. The percent changes with 95% confidence intervals (CIs) for a doubling of 3-PBA concentrations in the serum sex hormone levels were estimated using generalized linear regression models.

RESULTS

The overall median concentrations of creatinine-adjusted 3-PBA were 0.58 μg/g creatinine, and 90.0% of adults had a detectable level of 3-PBA. In females, every two-fold increase in 3-PBA was associated with 4.34% (95% CI: 1.58%, 7.18%) higher levels of TT and 4.05% (95% CI: 7.03%, 1.16%) higher levels of SHBG, respectively. In males, a doubling in 3-PBA was associated with 3.02% (95% CI: 1.21%, 4.86%) increase in SHBG but 1.85% (-3.59%, -0.07%) decrease in FAI, respectively. In addition, significant non-linear associations of 3-PBA with SHBG in both males and females and TT in females were observed.

CONCLUSIONS

Environmental pyrethroid exposure was associated with altered sex hormones in adults. This study provides important epidemiological evidence for the association of pyrethroids with endocrine disruption.

Optimized Ultrasound-Assisted Extraction of Lignans from Linum Species with Green Solvents

Lignans are plant phenols derived from phenylpropanoids. They play a significant role in plant defense and have features that make them appealing for pharmaceutical applications. Lignans can be obtained by plant in vitro cultures; their production by adventitious and hairy roots of Linum species seems to be a promising alternative to chemical synthesis. In the context of large-scale production, it is necessary to optimize their extraction from plants tissue by choosing the more suitable solvent and extraction procedure, paying attention to the use of green media and methods. With the aim to select the best conditions for the extraction of two interesting lignans (justicidin B and 6-methoxypodophyllotoxin) from Linum tissues, different green solvents and the method of ultrasound-assisted extraction were tested. The results showed that ethyl methyl ketone and dimethyl carbonate were the best media to extract justicidin B and 6-methoxypodophyllotoxin, respectively, in terms of purity and recovery. Moreover, we showed that ultrasound-assisted extraction presents different advantages compared to conventional methods. Finally, the optimal experimental conditions to extract justicidin B from L. austriacum hairy roots using methyl ethyl ketone were also determined by the response surface method. The models obtained are reliable and accurate to estimate the purity and recovery of justicidin B.

Association between exposure to polyfluoroalkyl chemicals and increased fractional exhaled nitric oxide in adults

BACKGROUND

Perfluoroalkyl chemicals (PFCs) are widely detected in the environment and human body, and they have been linked to asthma and a number of respiratory responses in children and mice. However, no previous studies have investigated the association between exposure to PFCs and airway inflammation in adults.

OBJECTIVES

To evaluate the associations between serum PFCs and fractional exhaled nitric oxide (FeNO), a biomarker of airway inflammation, in adults.

METHODS

A cross-sectional study of 3630 adults aged 20-79 years who participated in the National Health and Nutrition Examination Survey (NHANES, 2007-2012) was conducted. Serum concentrations of five major PFCs were measured using SPE-HPLC-TIS-MS/MS method, including perfluorohexane sulfonic acid (PFHxS), perfluorononanoic acid (PFNA), perfluorooctanoic acid (PFOA), perfluorooctane sulfonic acid (PFOS), and perfluorodecanoic acid (PFDE). The detection rates of them were all >85%. Weighted multivariable linear regression and Bayesian kernel machine regression (BKMR) analyses were applied to examine the associations between serum PFCs and FeNO.

RESULTS

After adjusted for potential confounding factors, linear regression analyses found that compared with their lowest tertiles, highest tertiles of PFOS, PFDE and PFOA were significantly associated with 5.02% (95% CI: 1.40%, 8.77%), 3.77% (95% CI: 0.30%, 7.36%) and 6.34% (95% CI: 2.81%, 10.01%) increases in FeNO, respectively. The second tertile of PFNA was significantly correlated with a 4.79% (95% CI: 1.41%, 8.29%) increase in FeNO compared with the lowest tertile. In the BKMR analysis, the mixture effect of PFCs on FeNO increased significantly when the PFC levels were at or above the 60th percentiles compared to those at their medians. PFOS and PFOA displayed significant positive single-exposure effects on FeNO when all the other PFCs are set at a particular threshold.

CONCLUSIONS

This study provided preliminary evidence that serum PFCs were positively associated with increased FeNO in adults.

Plant In Vitro Systems as a Sustainable Source of Active Ingredients for Cosmeceutical Application

Cosmeceuticals are hybrids between cosmetics and pharmaceuticals which are being designed for a dual purpose: (1) To provide desired esthetical effects and (2) simultaneously treat dermatological conditions. The increased demand for natural remedies and the trends to use natural and safe ingredients resulted in intensive cultivation of medicinal plants. However, in many cases the whole process of plant cultivation, complex extraction procedure, and purification of the targeted molecules are not economically feasible. Therefore, the desired production of natural cosmetic products in sustainable and controllable fashion in the last years led to the intensive utilization of plant cell culture technology. The present review aims to highlight examples of biosynthesis of active ingredients derived through plant in vitro systems with potential cosmeceutical application. The exploitation of different type of extracts used in a possible cosmeceutical formulation, as well as, their activity tested in in vitro/in vivo models is thoroughly discussed. Furthermore, opportunities to manipulate the biosynthetic pathway, hence engineering the biosynthesis of some secondary metabolites, such as anthocyanins, have been highlighted.

Tissue age, orchard location and disease management influence the composition of fungal and bacterial communities present on the bark of apple trees

Plants host microbial communities that can be affected by environmental conditions and agronomic practices. Despite the role of bark as a reservoir of plant pathogens and beneficial microorganisms, no information is available on the effects of disease management on the taxonomic composition of the bark-associated communities of apple trees. We assessed the impact of disease management strategies on fungal and bacterial communities on the bark of a scab-resistant apple cultivar in two orchard locations and for two consecutive seasons. The amplicon sequencing revealed that bark age and orchard location strongly affected fungal and bacterial diversity. Microbiota dissimilarity between orchards evolved during the growing season and showed specific temporal series for fungal and bacterial populations in old and young bark. Disease management did not induce global changes in the microbial populations across locations and seasons, but specifically affected the abundance of some taxa according to bark age, orchard location and sampling time. Therefore, the disease management applied to scab-resistant cultivars, which is based on a limited use of fungicides, partially changed the taxonomic composition of bark-associated fungal and bacterial communities, suggesting the need for a more accurate risk assessment regarding possible pathogen outbreaks.

Contributions of cryptochromes and phototropins to stomatal opening through the day

The UV-A/blue photoreceptors phototropins and cryptochromes are both known to contribute to stomatal opening (Δgs) in blue light. However, their relative contributions to the maintenance of gs in blue light through the whole photoperiod remain unknown. To elucidate this question, Arabidopsis phot1 phot2 and cry1 cry2 mutants (MTs) and their respective wild types (WTs) were irradiated with 200 μmolm-2s-1 of blue-, green- or red-light (BL, GL or RL) throughout a 11-h photoperiod. Stomatal conductance (gs) was higher under BL than under RL or GL. Under RL, gs was not affected by either of the photoreceptor mutations, but under GL gs was slightly lower in cry1 cry2 than its WT. Under BL, the presence of phototropins was essential for rapid stomatal opening at the beginning of the photoperiod, and maximal stomatal opening beyond 3 h of irradiation required both phototropins and cryptochromes. Time courses of whole-plant net carbon assimilation rate (Anet) and the effective quantum yield of PSII photochemistry (ΦPSII) were consistent with an Anet-independent contribution of BL on gs both in phot1 phot2 and cry1 cry2 mutants. The changing roles of phototropins and cryptochromes through the day may allow more flexible coordination between gs and Anet.

Time-dependent behavior of phenylpropanoid pathway in response to methyl jasmonate in Scrophularia striata cell cultures

MeJA triggers a time-dependent behavior of the phenylpropanoid compounds. Plant cells produce a large number of metabolites in response to environmental factors. The cellular responses to environmental changes are orchestrated by signaling molecules, such as methyl jasmonate (MeJA). To understand how the MeJA changes the behavior of amino acids, carbohydrates, and phenylpropanoid compounds such as phenolic acids, phenylethanoid-glycosides, and flavonoids in Scrophularia striata cells; we monitored the metabolic responses for different times of exposure. In this study, we performed a time course analysis of metabolites and enzymes in S. striata cells exposed to MeJA (100 µM) and evaluated the metabolic flux towards carbon-rich secondary metabolites production. Moreover, we calculated the biosynthetic energy cost for free amino acids. Our results indicated that MeJA accelerates the sucrose degradation and directs the metabolic fluxes towards a pool of flavonoids and phenylethanoid glycosides through a change in enzyme behavior in the entry point and center of the phenylpropanoid pathway. MeJA also decreased and then raised the amino acid biosynthesis cost in S. striata cells in a time-dependent manner, indicating the cells evolve to utilize amino acids more economically by reducing cell growth. Finally, we classified the marked changes in the metabolites level and enzyme activities into three groups including early-, late-, and oscillatory-response groups to MeJA and summarized our findings as a model depicting pathway interactions during MeJA elicitation. Determination of metabolic levels in response to MeJA suggests that the changes in metabolic responses are time-dependent.

Accumulation of Anthocyanin and Its Associated Gene Expression in Purple Tumorous Stem Mustard ( Brassica juncea var. tumida Tsen et Lee) Sprouts When Exposed to Light, Dark, Sugar, and Methyl Jasmonate

Tumorous stem mustard is a characteristic vegetable in Southeast Asia, as are its sprouts. The purple color of the purple variety 'Zi Ying' leaves is because of anthocyanin accumulation. The ways in which this anthocyanin accumulation is affected by the environment and hormones has remained unclear. Here, the impacts of sucrose, methyl jasmonate (MeJA), light, and dark on the growth and anthocyanin production of 'Zi Ying' sprouts were explored. The results showed that anthocyanins can be enhanced by sucrose in sprouts under light condition, and MeJA can promote anthocyanins production under light and dark conditions in sprouts. The anthocyanin biosynthetic regulatory genes BjTT8, BjMYB1, BjMYB2 and BjMYB4, and the EBGs and LBGs were upregulated under light conditions, while BjTT8, BjMYB1, and BjMYB2 and anthocyanin biosynthetic genes BjF3H and BjF3'H were upregulated under DM condition. These results indicate that sucrose and methyl jasmonate can stimulate the expression of genes encoding components of the MBW complex (MYB, bHLH, and WD40) and that they transcriptional activated the expression of LBGs and EBGs to promote the accumulation of anthocyanins in 'Zi Ying' sprouts. Our findings enhance our understanding of anthocyanin accumulation regulated by sucrose and MeJA in 'Zi Ying', which will help growers to produce anthocyanin-rich foods with benefits to human health.

Nutrimetabolomics: An Integrative Action for Metabolomic Analyses in Human Nutritional Studies

The life sciences are currently being transformed by an unprecedented wave of developments in molecular analysis, which include important advances in instrumental analysis as well as biocomputing. In light of the central role played by metabolism in nutrition, metabolomics is rapidly being established as a key analytical tool in human nutritional studies. Consequently, an increasing number of nutritionists integrate metabolomics into their study designs. Within this dynamic landscape, the potential of nutritional metabolomics (nutrimetabolomics) to be translated into a science, which can impact on health policies, still needs to be realized. A key element to reach this goal is the ability of the research community to join, to collectively make the best use of the potential offered by nutritional metabolomics. This article, therefore, provides a methodological description of nutritional metabolomics that reflects on the state-of-the-art techniques used in the laboratories of the Food Biomarker Alliance (funded by the European Joint Programming Initiative "A Healthy Diet for a Healthy Life" (JPI HDHL)) as well as points of reflections to harmonize this field. It is not intended to be exhaustive but rather to present a pragmatic guidance on metabolomic methodologies, providing readers with useful "tips and tricks" along the analytical workflow.

Two amino acid changes in the R3 repeat cause functional divergence of two clustered MYB10 genes in peach

R2R3-MYB genes play a pivotal role in regulating anthocyanin accumulation. Here, we report two tandemly duplicated R2R3-MYB genes in peach, PpMYB10.1 and PpMYB10.2, with the latter showing lower ability to induce anthocyanin accumulation than the former. Site-directed mutation assay revealed two amino acid changes in the R3 repeat, Arg/Lys⁶⁶ and Gly/Arg⁹³, responsible for functional divergence between these two PpMYB10 genes. Anthocyanin-promoting activity of PpMYB10.2 was significantly increased by a single amino acid replacement of Arg⁹³ with Gly⁹³. However, either the Gly⁹³ → Arg⁹³ or Arg⁶⁶ → Lys⁶⁶ substitutions alone showed little impact on anthocyanin-promoting activity of PpMYB10.1, but simultaneous substitutions caused a significant decrease. Reciprocal substitution of Arg/Gly⁹³ could significantly alter binding affinity to PpbHLH3, while the Arg⁶⁶ → Lys⁶⁶ substitution is predicted to affect the folding of the MYB DNA-binding domain, instead of PpbHLH3-binding affinity. Overall, the change of anthocyanin-promoting activity was accompanied with that of bHLH-binding affinity, suggesting that DNA-binding affinity of R2R3-MYBs depends on their bHLH partners. Our study is helpful for understanding of functional evolution of R2R3-MYBs and their interaction with DNA targets.