Metabolic mechanism of Astragalus membranaceus (Fisch.) Bge. var. mongholicus (Bge.) Hsiao in response to repeated drought stress

Abstract [Objective] Astragalus membranaceus (Fisch.) Bge. var. mongholicus (Bge.) Hsiao is an important primitive plant of astragali radix, and its main planting areas are arid and semi-arid areas in Inner Mongolia, Shanxi, Gansu, and other places. Irregular intermittent rainfalls cause drought and rehydration cycle in plants. Studying the characteristics of metabolites in A . membranaceus var. mongholicus during drought and rehydration is crucial to understand the drought tolerance mechanism in response to natural intermittent rainfalls. [Methods] The seedlings of annual A . membranaceus var. mongholicus were used as materials. After repeated drought and rehydration treatment, soil nutrients and root growth in potted plants were measured. The primary metabolites of A . membranaceus var. mongholicus were analyzed using NMR based technology. Differential metabolite screening and metabolic pathway were analyzed. Total flavonoids, total saponins, and polysaccharides in the roots of A . membranaceus var. mongholicus were determined. [Results] (1) A . membranaceus var. mongholicus showed a trend of decreasing in root diameter and increasing in root length and fibrous root density under drought stress. (2) Under drought and rehydration treatment, a total of 42 metabolites were detected, containing mainly amino acids and their derivatives, organic acids, amines, ammonia compounds, and sugars. Metabolic pathway analysis showed that amino acid metabolism pathways were mainly affected during repeated drought stress. Plant drought resistance was enhanced by increasing the content of aspartate, alanine, glutamate, proline, and arginine, as well as reducing the content of asparagine, tryptophan, and 4-aminobutyrate. Specifically, the increase in metabolites such as alanine, glutamate, and proline was 1-3 times, while metabolites such as tryptophan and 4-aminobutyric acid were decreased by 1-2 times. (3) Under the first round of drought stress, the accumulation of astragaloside was decreased; after the second round of drought stress, the production of three active substances, namely astragaloside, total flavonoids, and polysaccharides, showed a downward trend. [Conclusion] Amino acids and their derivatives are closely related in response to drought stress in A . membranaceus var. mongholicus. Plant regulates its secondary metabolites in response to environmental change

A multi-tissue transcriptomic landscape of female mice in estrus and diestrus provides clues for precision medicine

Female reproductive cycle, also known as menstrual cycle or estrous cycle in primate or non-primate mammals, respectively, dominates the reproductive processes in non-pregnant state. However, in addition to reproductive tissues, reproductive cycle could also perform global regulation because the receptors of two major female hormones fluctuating throughout the cycle, estrogen and progesterone, are widely distributed. Therefore, a multi-tissue gene expression landscape is in continuous demand for better understanding the systemic changes during the reproductive cycle but remains largely undefined. Here we delineated a transcriptomic landscape covering 15 tissues of C57BL/6J female mice in two phases of estrous cycle, estrus and diestrus, by RNA-sequencing. Then, a number of genes, pathways, and transcription factors involved in the estrous cycle were revealed. We found the estrous cycle could widely regulate the neuro-functions, immuno-functions, blood coagulation and so on. And behind the transcriptomic alteration between estrus and diestrus, 13 transcription factors may play important roles. Next, bioinformatics modeling with 1,263 manually curated gene signatures of various physiological and pathophysiological states systematically characterized the beneficial/deleterious effects brought by estrus/diestrus on individual tissues. We revealed that the estrous cycle has a significant effect on cardiovascular system (aorta, heart, vein), in which the anti-hypertensive pattern in aorta induced by estrus is one of the most striking findings. Inspired by this point, we validated that two hypotensive drugs, felodipine and acebutolol, could exhibit significantly enhanced efficacy in estrus than diestrus by mouse and rat experiments. Together, this study provides a valuable data resource for investigating reproductive cycle from a transcriptomic perspective, and presents models and clues for investigating precision medicine associated with reproductive cycle

Efficient Fractionation of Green Bamboo Using an Integrated Hydrothermal–Deep Eutectic Solvent Pretreatment for Its Valorization

Adopting an integrated strategy to realize efficient fractionation of lignocellulose into well-defined components for its valorization is challenging. Combinatorial pretreatments in this study decomposed hemicellulose of green bamboo during hydrothermal pretreatment (HP), and the hydrothermally pretreated bamboo was subsequently subjected to delignification using deep eutectic solvent (DES) consisting of choline chloride and lactic acid, finally facilitating enzymatic hydrolysis of cellulose residue. Upon hydrothermal treatment at 180 °C for 35 min, hemicellulose removal of 88.6% was achieved with xylo-oligosaccharide yield and purity of 50.9% and 81.6%, respectively. After DES treatment at 140 °C for 2 h, lignin removal was determined to be 79.1%. Notably, the regenerated lignin with high purity of 96.8% displayed superior antioxidant activity, and the decrease in the ratio of syringyl units to guaiacyl units led to a slight decrease in radical scavenging activity of lignin after five recycling runs of DES. Moreover, the two-step treated residue had much higher enzymatic digestibility than that of single HP residue and untreated green bamboo. Results show that synergistic pretreatment is a promising strategy to tackle the recalcitrance of lignocellulose towards high value-added utilization

PIMT/NCOA6IP Deletion in the Mouse Heart Causes Delayed Cardiomyopathy Attributable to Perturbation in Energy Metabolism

PIMT/NCOA6IP, a transcriptional coactivator PRIP/NCOA6 binding protein, enhances nuclear receptor transcriptional activity. Germline disruption of PIMT results in early embryonic lethality due to impairment of development around blastocyst and uterine implantation stages. We now generated mice with Cre-mediated cardiac-specific deletion of PIMT (csPIMT−/−) in adult mice. These mice manifest enlargement of heart, with nearly 100% mortality by 7.5 months of age due to dilated cardiomyopathy. Significant reductions in the expression of genes (i) pertaining to mitochondrial respiratory chain complexes I to IV; (ii) calcium cycling cardiac muscle contraction (Atp2a1, Atp2a2, Ryr2); and (iii) nuclear receptor PPAR- regulated genes involved in glucose and fatty acid energy metabolism were found in csPIMT−/− mouse heart. Elevated levels of Nppa and Nppb mRNAs were noted in csPIMT−/− heart indicative of myocardial damage. These hearts revealed increased reparative fibrosis associated with enhanced expression of Tgfβ2 and Ctgf. Furthermore, cardiac-specific deletion of PIMT in adult mice, using tamoxifen-inducible Cre-approach (TmcsPIMT−/−), results in the development of cardiomyopathy. Thus, cumulative evidence suggests that PIMT functions in cardiac energy metabolism by interacting with nuclear receptor coactivators and this property could be useful in the management of heart failure

DCLK1 Suppresses Tumor-Specific Cytotoxic T Lymphocyte Function Through Recruitment of MDSCs via the CXCL1-CXCR2 AxisSummary

Background & Aims: Gastrointestinal cancer stem cell marker doublecortin-like kinase (DCLK1) is strongly associated with poor outcomes in colorectal cancer (CRC). Although DCLK1’s regulatory effect on the tumor immune microenvironment has been hypothesized, its mode of action has not been shown previously in vivo, which hampers the potential intervention based on this molecule for clinical practice. Methods: To define the immunomodulatory mechanisms of DCLK1 in vivo, we generated DCLK1-/- tumor cells by Clustered regularly interspaced short palindromic repeats (CRISPR)-CRISPR-associated protein 9 (Cas9) and developed subcutaneous and intestinal orthotopic transplantation tumor models. Tumor tissues were harvested and subjected to immunofluorescence staining, flow cytometry analysis of tumor-infiltrating immune cell populations, tumor myeloid-derived suppressor cell (MDSC) sorting by isolation kit and then co-culture with spleen T cells, and RNA sequencing for transcriptomic analysis. Results: We found that DCLK1-/- tumor cells lose their tumorigenicity under immune surveillance. Failed tumor establishment of DCLK1-/- was associated with an increase in infiltration of CD8+ T cells and effector CD4+ T cells, and reduced numbers of MDSCs in the tumor tissue. Furthermore, DCLK1 promoted the up-regulation of C-X-C motif ligand 1, which recruits MDSCs in CRC through chemokine C-X-C motif receptor 2. The ability of in vivo tumor growth of DCLK1-/- tumor cells was rescued by C-X-C motif ligand 1 overexpression. Collectively, we validated that DCLK1 promotes tumor growth in CRC through recruitment of T-cell–suppressive MDSCs. Conclusions: DCLK1-mediated immune suppression in tumor models allows escaping from the host’s antitumor response. Because DCLK1 is one of the most common markers in gastrointestinal tumors, these results identify a precise therapeutic target for related clinical interventions