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Microbial Peer Pressure: The Role of the Gut Microbiota in Hypertension and Its Complications

Muralitharan RR, Jama HA, Xie L, Peh A, Snelson M, Marques FZ

Hypertension, 2020 12;76(6):1674-1687.
PMID: 33012206 DOI: 10.1161/HYPERTENSIONAHA.120.14473

There is increasing evidence of the influence of the gut microbiota on hypertension and its complications, such as chronic kidney disease, stroke, heart failure, and myocardial infarction. This is not surprising considering that the most common risk factors for hypertension, such as age, sex, medication, and diet, can also impact the gut microbiota. For example, sodium and fermentable fiber have been studied in relation to both hypertension and the gut microbiota. By combining second- and, now, third-generation sequencing with metabolomics approaches, metabolites, such as short-chain fatty acids and trimethylamine N-oxide, and their producers, have been identified and are now known to affect host physiology and the cardiovascular system. The receptors that bind these metabolites have also been explored with positive findings-examples include known short-chain fatty acid receptors, such as G-protein coupled receptors GPR41, GPR43, GPR109a, and OLF78 in mice. GPR41 and OLF78 have been shown to have inverse roles in blood pressure regulation, whereas GPR43 and GPR109A have to date been demonstrated to impact cardiac function. New treatment options in the form of prebiotics (eg, dietary fiber), probiotics (eg, Lactobacillus spp.), and postbiotics (eg, the short-chain fatty acids acetate, propionate, and butyrate) have all been demonstrated to be beneficial in lowering blood pressure in animal models, but the underlying mechanisms remain poorly understood and translation to hypertensive patients is still lacking. Here, we review the evidence for the role of the gut microbiota in hypertension, its risk factors, and cardiorenal complications and identify future directions for this exciting and fast-evolving field.
Correction to: Estrogen receptor alpha mediates 17β-estradiol, up-regulates autophagy and alleviates hydrogen peroxide-induced vascular senescence

Xiang X, Xie L, Lin J, Pare R, Huang G, Huang J, et al.

Biogerontology, 2023 Apr 28.
PMID: 37115350 DOI: 10.1007/s10522-023-10033-2
Estrogen receptor alpha mediates 17β-estradiol, up-regulates autophagy and alleviates hydrogen peroxide-induced vascular senescence

Xiang X, Xie L, Lin J, Pare R, Huang G, Huang J, et al.

Biogerontology, 2023 Oct;24(5):783-799.
PMID: 36683095 DOI: 10.1007/s10522-023-10015-4

Atherosclerosis threatens human health by developing cardiovascular diseases, the deadliest disease world widely. The major mechanism contributing to the formation of atherosclerosis is mainly due to vascular endothelial cell (VECs) senescence. We have shown that 17β-estradiol (17β-E2) may protect VECs from senescence by upregulating autophagy. However, little is known about how 17β-E2 activates the autophagy pathway to alleviate cellular senescence. Therefore, the aim of this study is to determine the role of estrogen receptor (ER) α and β in the effects of 17β-E2 on vascular autophagy and aging through in vitro and in vivo models. Hydrogen peroxide (H2O2) was used to establish Human Umbilical Vein Endothelial Cells (HUVECs) senescence. Autophagy activity was measured through immunofluorescence and immunohistochemistry staining of light chain 3 (LC3) expression. Inhibition of ER activity was established using shRNA gene silencing and ER antagonist. Compared with ER-β knockdown, we found that knockdown of ER-α resulted in a significant increase in the extent of HUVEC senescence and senescence-associated secretory phenotype (SASP) secretion. ER-α-specific shRNA was found to reduce 17β-E2-induced autophagy, promote HUVEC senescence, disrupt the morphology of HUVECs, and increase the expression of Rb dephosphorylation and SASP. These in vitro findings were found consistent with the in vivo results. In conclusion, our data suggest that 17β-E2 activates the activity of ER-α and then increases the formation of autophagosomes (LC3 high expression) and decreases the fusion of lysosomes with autophagic vesicles (P62 low expression), which in turn serves to decrease the secretion of SASP caused by H2O2 and consequently inhibit H2O2-induced senescence in HUVEC cells.
Improving Perovskite Solar Cell Performance and Stability via Thermal Imprinting-Assisted Ion Exchange Passivation

Qi S, Ge C, Wang P, Wu B, Zhao Y, Zhao R, et al.

ACS Appl Mater Interfaces, 2024 Sep 11.
PMID: 39261789 DOI: 10.1021/acsami.4c08538

The latest development in perovskite solar cell (PSC) technology has been significantly influenced by advanced techniques aimed at passivating surface defects. This work presents a new approach called thermal imprinting-assisted ion exchange passivation (TIAIEP), which delivers a different approach to conventional solution-based methods. TIAIEP focuses on addressing surface imperfections in solid-state films by using a passivator that promotes ion exchange specifically at the defect sites within the perovskite layer. By adjusting the time and temperature of the TIAIEP process, we achieve substantial enhancement in the creation of a compositional gradient within the films. This optimization slows the cooling rate of hot carriers, leading to minimizing charge recombination and improving the device performance. Remarkably, devices treated with TIAIEP achieve a 22.29% power conversion efficiency and show outstanding stability, with unencapsulated PSCs maintaining 91% of their original efficiency after over 2000 h of storage and 90% efficiency after 1200 h of constant illumination. These results highlight TIAIEP's effectiveness in mitigating surface defects, improving both the photoelectric and stability performance of PSCs, and indicating significant potential for large-scale application in perovskite film passivation, promoting the widespread adoption of this technology.
Electrospun microcrystalline cellulose/chitosan porous composite nanofibrous membranes modified by non-thermal plasma for gaseous formaldehyde adsorption

Xiong J, Luo R, Jia Z, Ge S, Lam SS, Xie L, et al.

Int J Biol Macromol, 2024 Jan;256(Pt 2):128399.
PMID: 38007014 DOI: 10.1016/j.ijbiomac.2023.128399

To develop a green and facile adsorbent for removing indoor polluted formaldehyde (HCHO) gas, the biomass porous nanofibrous membranes (BPNMs) derived from microcrystalline cellulose/chitosan were fabricated by electrospinning. The enhanced chemical adsorption sites with diverse oxygen (O) and nitrogen (N)-containing functional groups were introduced on the surface of BPNMs by non-thermal plasma modification under carbon dioxide (CO2) and nitrogen (N2) atmospheres. The average nanofiber diameters of nanofibrous membranes and their nanomechanical elastic modulus and hardness values decreased from 341 nm to 175-317 nm and from 2.00 GPa and 0.25 GPa to 1.70 GPa and 0.21 GPa, respectively, after plasma activation. The plasma-activated nanofibers showed superior hydrophilicity (WCA = 0°) and higher crystallinity than that of the control. The optimal HCHO adsorption capacity (134.16 mg g-1) of BPNMs was achieved under a N2 atmosphere at a plasma power of 30 W and for 3 min, which was 62.42 % higher compared with the control. Pyrrolic N, pyridinic N, CO and O-C=O were the most significant O and N-containing functional groups for the improved chemical adsorption of the BPNMs. The adsorption mechanism involved a synergistic combination of physical and chemical adsorption. This study provides a novel strategy that combines clean plasma activation with electrospinning to efficiently remove gaseous HCHO.
Vonoprazan 10 mg or 20 mg vs. lansoprazole 15 mg as maintenance therapy in Asian patients with healed erosive esophagitis: A randomized controlled trial

Xiao Y, Qian J, Zhang S, Dai N, Chun HJ, Chiu C, et al.

Chin Med J (Engl), 2024 Apr 20;137(8):962-971.
PMID: 38654422 DOI: 10.1097/CM9.0000000000003068

BACKGROUND: Erosive esophagitis (EE) is a gastroesophageal reflux disease characterized by mucosal breaks in the esophagus. Proton pump inhibitors are widely used as maintenance therapy for EE, but many patients still relapse. In this trial, we evaluated the noninferiority of vonoprazan vs. lansoprazole as maintenance therapy in patients with healed EE.
METHODS: We performed a double-blind, double-dummy, multicenter, phase 3 clinical trial among non-Japanese Asian adults with endoscopically confirmed healed EE from April 2015 to February 2019. Patients from China, South Korea, and Malaysia were randomized to vonoprazan 10 mg or 20 mg once daily or lansoprazole 15 mg once daily for 24 weeks. The primary endpoint was endoscopically confirmed EE recurrence rate over 24 weeks with a noninferiority margin of 10% using a two-sided 95% confidence interval (CI). Treatment-emergent adverse events (TEAEs) were recorded.
RESULTS: Among 703 patients, EE recurrence was observed in 24/181 (13.3%) and 21/171 (12.3%) patients receiving vonoprazan 10 mg or 20 mg, respectively, and 47/184 (25.5%) patients receiving lansoprazole (differences: -12.3% [95% CI, -20.3% to -4.3%] and -13.3% [95% CI, -21.3% to -5.3%], respectively), meeting the primary endpoint of noninferiority to lansoprazole in preventing EE recurrence at 24 weeks. Evidence of superiority (upper bound of 95% CI <0%) was also observed. At 12 weeks, endoscopically confirmed EE recurrence was observed in 5/18, 2/20, and 7/20 of patients receiving vonoprazan 10 mg, vonoprazan 20 mg, and lansoprazole, respectively. TEAEs were experienced by 66.8% (157/235), 69.0% (156/226), and 65.3% (158/242) of patients receiving vonoprazan 10 mg, vonoprazan 20 mg, and lansoprazole, respectively. The most common TEAE was upper respiratory tract infection in 12.8% (30/235) and 12.8% (29/226) patients in vonoprazan 10 mg and 20 mg groups, respectively and 8.7% (21/242) patients in lansoprazole group.
CONCLUSION: Vonoprazan maintenance therapy was well-tolerated and noninferior to lansoprazole for preventing EE recurrence in Asian patients with healed EE.
TRIAL REGISTRATION: https://clinicaltrials.gov; NCT02388737.
Efficient Cr(VI) remediation by electrospun composite porous nanofibers incorporating biomass with metal oxides and metal-organic framework

Luo R, Li R, Zheng Z, Zhang L, Xie L, Wu C, et al.

Environ Pollut, 2024 Apr 23;351:124026.
PMID: 38663509 DOI: 10.1016/j.envpol.2024.124026

To develop a highly efficient adsorbent to remediate and remove hexavalent chromium ions (Cr(VI)) from polluted water, cellulose acetate (CA) and chitosan (CS), along with metal oxides (titanium dioxide (TiO2) and ferroferric oxide (Fe3O4)), and a zirconium-based metal-organic framework (UiO-66) were used to fabricate the composite porous nanofiber membranes through electrospinning. The adsorption performance, influencing factors, adsorption kinetics and isotherms of composite nanofiber membranes were comprehensively investigated. The multi-layer membrane with interpenetrating nanofibers and surface functional groups enhanced the natural physical adsorption and provided potential chemical sites. The thermal stability was improved by introducing TiO2 and UiO-66. CA/CS/UiO-66 exhibited the highest adsorption capacity (118.81 mg g-1) and removal rate (60.76%), which were twice higher than those of the control. The correlation coefficients (R2) of all the composite nanofibers regressed by the Langmuir model were significantly higher than those by the Freundlich model. The pseudo-first-order kinetic curve of CA/CS composite nanofibers showed the highest R2 (0.973), demonstrating that the whole adsorption process involved a combination of strong physical adsorption and weak chemical adsorption by the amino groups of CS. However, the R2 values of the pseudo-second-order kinetic model increased after incorporating TiO2, Fe3O4, and UiO-66 into the CA/CS composite nanofiber membranes since an enhanced chemical reaction with Cr (VI) occured during the adsorption.
Fulltext A reference genome of Commelinales provides insights into the commelinids evolution and global spread of water hyacinth (Pontederia crassipes)

Huang Y, Guo L, Xie L, Shang N, Wu D, Ye C, et al.

Gigascience, 2024 Jan 02;13.
PMID: 38486346 DOI: 10.1093/gigascience/giae006

Commelinales belongs to the commelinids clade, which also comprises Poales that includes the most important monocot species, such as rice, wheat, and maize. No reference genome of Commelinales is currently available. Water hyacinth (Pontederia crassipes or Eichhornia crassipes), a member of Commelinales, is one of the devastating aquatic weeds, although it is also grown as an ornamental and medical plant. Here, we present a chromosome-scale reference genome of the tetraploid water hyacinth with a total length of 1.22 Gb (over 95% of the estimated size) across 8 pseudochromosome pairs. With the representative genomes, we reconstructed a phylogeny of the commelinids, which supported Zingiberales and Commelinales being sister lineages of Arecales and shed lights on the controversial relationship of the orders. We also reconstructed ancestral karyotypes of the commelinids clade and confirmed the ancient commelinids genome having 8 chromosomes but not 5 as previously reported. Gene family analysis revealed contraction of disease-resistance genes during polyploidization of water hyacinth, likely a result of fitness requirement for its role as a weed. Genetic diversity analysis using 9 water hyacinth lines from 3 continents (South America, Asia, and Europe) revealed very closely related nuclear genomes and almost identical chloroplast genomes of the materials, as well as provided clues about the global dispersal of water hyacinth. The genomic resources of P. crassipes reported here contribute a crucial missing link of the commelinids species and offer novel insights into their phylogeny.
Fulltext Influence of angiotensin II on the gut microbiome: modest effects in comparison to experimental factors

R Muralitharan R, Nakai ME, Snelson M, Zheng T, Dinakis E, Xie L, et al.

Cardiovasc Res, 2024 Sep 02;120(10):1155-1163.
PMID: 38518247 DOI: 10.1093/cvr/cvae062

AIMS: Animal models are regularly used to test the role of the gut microbiome in hypertension. Small-scale pre-clinical studies have investigated changes to the gut microbiome in the angiotensin II hypertensive model. However, the gut microbiome is influenced by internal and external experimental factors, which are not regularly considered in the study design. Once these factors are accounted for, it is unclear if microbiome signatures are reproduceable. We aimed to determine the influence of angiotensin II treatment on the gut microbiome using a large and diverse cohort of mice and to quantify the magnitude by which other factors contribute to microbiome variations.
METHODS AND RESULTS: We conducted a retrospective study to establish a diverse mouse cohort resembling large human studies. We sequenced the V4 region of the 16S rRNA gene from 538 samples across the gastrointestinal tract of 303 male and female C57BL/6J mice randomized into sham or angiotensin II treatment from different genotypes, diets, animal facilities, and age groups. Analysing over 17 million sequencing reads, we observed that angiotensin II treatment influenced α-diversity (P = 0.0137) and β-diversity (i.e. composition of the microbiome, P < 0.001). Bacterial abundance analysis revealed patterns consistent with a reduction in short-chain fatty acid producers, microbial metabolites that lower blood pressure. Furthermore, animal facility, genotype, diet, age, sex, intestinal sampling site, and sequencing batch had significant effects on both α- and β-diversity (all P < 0.001). Sampling site (6.8%) and diet (6%) had the largest impact on the microbiome, while angiotensin II and sex had the smallest effect (each 0.4%).
CONCLUSION: Our large-scale data confirmed findings from small-scale studies that angiotensin II impacted the gut microbiome. However, this effect was modest relative to most of the other factors studied. Accounting for these factors in future pre-clinical hypertensive studies will increase the likelihood that microbiome findings are replicable and translatable.
Fulltext Genomic insights into the evolution of Echinochloa species as weed and orphan crop

Wu D, Shen E, Jiang B, Feng Y, Tang W, Lao S, et al.

Nat Commun, 2022 02 03;13(1):689.
PMID: 35115514 DOI: 10.1038/s41467-022-28359-9

As one of the great survivors of the plant kingdom, barnyard grasses (Echinochloa spp.) are the most noxious and common weeds in paddy ecosystems. Meanwhile, at least two Echinochloa species have been domesticated and cultivated as millets. In order to better understand the genomic forces driving the evolution of Echinochloa species toward weed and crop characteristics, we assemble genomes of three Echinochloa species (allohexaploid E. crus-galli and E. colona, and allotetraploid E. oryzicola) and re-sequence 737 accessions of barnyard grasses and millets from 16 rice-producing countries. Phylogenomic and comparative genomic analyses reveal the complex and reticulate evolution in the speciation of Echinochloa polyploids and provide evidence of constrained disease-related gene copy numbers in Echinochloa. A population-level investigation uncovers deep population differentiation for local adaptation, multiple target-site herbicide resistance mutations of barnyard grasses, and limited domestication of barnyard millets. Our results provide genomic insights into the dual roles of Echinochloa species as weeds and crops as well as essential resources for studying plant polyploidization, adaptation, precision weed control and millet improvements.
Fulltext Diversity of global rice markets and the science required for consumer-targeted rice breeding

Calingacion M, Laborte A, Nelson A, Resurreccion A, Concepcion JC, Daygon VD, et al.

PLoS One, 2014;9(1):e85106.
PMID: 24454799 DOI: 10.1371/journal.pone.0085106

With the ever-increasing global demand for high quality rice in both local production regions and with Western consumers, we have a strong desire to understand better the importance of the different traits that make up the quality of the rice grain and obtain a full picture of rice quality demographics. Rice is by no means a 'one size fits all' crop. Regional preferences are not only striking, they drive the market and hence are of major economic importance in any rice breeding / improvement strategy. In this analysis, we have engaged local experts across the world to perform a full assessment of all the major rice quality trait characteristics and importantly, to determine how these are combined in the most preferred varieties for each of their regions. Physical as well as biochemical characteristics have been monitored and this has resulted in the identification of no less than 18 quality trait combinations. This complexity immediately reveals the extent of the specificity of consumer preference. Nevertheless, further assessment of these combinations at the variety level reveals that several groups still comprise varieties which consumers can readily identify as being different. This emphasises the shortcomings in the current tools we have available to assess rice quality and raises the issue of how we might correct for this in the future. Only with additional tools and research will we be able to define directed strategies for rice breeding which are able to combine important agronomic features with the demands of local consumers for specific quality attributes and hence, design new, improved crop varieties which will be awarded success in the global market.

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