Extraction optimization, structure modification and immunomodulatory activity in vitro for arabinoxylans from cereals

BACKGROUD: The industrial cereal brans produced as by-products of milling have been confirmed to be rich sources of arabinoxylans (AXs). The immunomodulatory properties of the extracted AXs from cereals have been reported, which potentially lead to corresponding health benefit in immune enhancement. However, this requires a clearer understanding of the relationship between the molecular structures of AXs and their immune-modulating activities (the structure-activity relationship). It is also considered essential to gain an understanding of the mechanisms of the immune-modulating properties of AXs. AIMS & DESIGN: The aims of this study were to develop and improve the AXs extraction process from pentosan fraction of wheat flour and corn bran and to examine the molecular structures of extracted and modified AXs and investigate the molecular structure-immunomodulatory activity relationship in vitro for AXs. The effects of the different enzymatic extraction conditions (endoxylanase dosage, extraction temperature and time) on AXs extraction yield from the pentosan fraction of wheat flour were investigated by using a Box-Behnken experimental design and response surface methodology. For the AXs extraction process from corn bran, various extraction methods (alkaline, aqueous and enzyme extraction methods) were studied and compared. In addition, the treatments of three varieties of endoxylanases for AX molecular structure modification were studied. Furthermore, the extracted and modified AXs with different molecular structures were investigated with respect to their ability to modulate nitric oxide (NO) production and inducible NO synthase (iNOS) expression in vitro as an indication of their immunomodulatory potential. RESULTS: From the pentosan fraction, the maximum recovery rate of AXs reached 86% of total pentosan AXs (dry matter basis) under the optimum extraction conditions. In contrast to the AXs obtained by aqueous extraction, the molecular weight (Mw) distribution of enzymatically extracted AXs was significantly different being more concentrated in the low Mw range (1KDa to 10KDa). The degree of branching (A/X ratio) increased from 0.48 to 0.83 as the concentration of enzyme increased. From the corn bran, using alkaline treatment, the recovery rate of AX was up to 80% (dry matter basis) of total corn bran AX and the Mw distribution of extracted AXs was in the high Mw range (100KDa to 794KDa). Following enzymatic modification, more than 30% of AXs extracted were reduced to the lower Mw range (0.1KDa to 10KDa). In vitro studies showed that the extracted and modified AXs from these two cereal sources significantly elevated the level of NO synthesis and iNOS expression by U937 cells (p<0.05), but modified AXs with higher portion of low Mw showed stronger activity than extracted AXs with higher portion of high Mw (p<0.05). It was also observed that the stimulatory effect of AXs on NO production by U937 cells was associated with their concentrations and sources. In addition, the investigation on the immune-modulatory activity of AXs extracted from 10 cereal sources showed that the stimulatory effect of AXs on NO production by U937 cells seems to be associated with average molecular weight. More interestingly, it was noted that extracted and modified AXs had a significantly different effect on iNOS expression in U937 cells (p<0.05), suggesting that NO synthesis stimulated by AXs in vitro is closely mirrored by iNOS expression. CONCLUSIONS: As results of this study, the extraction process of AXs from corn bran and pentosan fraction of wheat flour was optimised. The conditions for modifying the molecular features of AXs were standardised. The experimental conditions for controlling the Mw distributions produced during the extraction and modification in order to enhance the immune-modulating activities of the AXs. The results of in vitro assessments should be useful in further understanding the mechanisms of the structure-activity relationship of AXs

Characterization of Nitric Oxide Modulatory Activities of Alkaline-Extracted and Enzymatic-Modified Arabinoxylans from Corn Bran in Cultured Human Monocytes

This document is the Accepted Manuscript version of a Published Work that appeared in final form in Journal of Agricultural and Food Chemistry, copyright © American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see https://pubs.acs.org/doi/pdf/10.1021/acs.jafc.6b02896The ingestion of foods and food-derived substances that may mediate the immune system is widely studied. Evidence suggests cereal arabinoxylans (AXs) have immunomodulatory activities that may impart health benefits in terms of immune enhancement. This study extracted AXs from corn bran using alkali and developed a modification process using three endoxylanases to obtain fractions of lower molecular weight ranges. In vitro studies showed extracted and modified AXs significantly (P < 0.05) elevated nitric oxide (NO) synthesis by the human U937 monocytic cell line (ranging from 53.7 ± 1.1 to 62.9 ± 1.2 μM per million viable cells) at all concentrations tested (5–1000 μg/mL), indicative of immune enhancement compared to an untreated control (43.7 ± 1.9 μM per million viable cells). The study suggested the dose range and Mw distribution of AXs are key determinants of immune-modulatory activity. AXs in the low Mw range (0.1–10 KDa) were the most effective at inducing NO secretion by U937 macrophages at low AX concentration ranges (5–50 μg/mL), with NO production peaking at 62.9 ± 1.2 μM per million viable cells with 5 μg/mL of AX (P = 0.0009). In contrast, AXs in the high Mw range (100–794 kDa) were most effective at inducing NO at high AX concentration ranges (500–1000 μg/mL) with NO production reaching a maximum of 62.7 ± 1.3 μM per million viable cells at 1000 μg/mL of AX (P = 0.0011). The findings suggest that dietary AXs from corn bran may heighten innate immune responses in the absence of infection or disease

Rational design of a DNA sequence-specific modular protein tag by tuning the alkylation kinetics

Sequence-selective chemical modification of DNA by synthetic ligands has been a long-standing challenge in the field of chemistry. Even when the ligand consists of a sequence-specific DNA binding domain and reactive group, sequence-selective reactions by these ligands are often accompanied by off-target reactions. A basic principle to design DNA modifiers that react at specific sites exclusively governed by DNA sequence recognition remains to be established. We have previously reported selective DNA modification by a self-ligating protein tag conjugated with a DNA-binding domain, termed as a modular adaptor, and orthogonal application of modular adaptors by relying on the chemoselectivity of the protein tag. The sequence-specific crosslinking reaction by the modular adaptor is thought to proceed in two steps: the first step involves the formation of a DNA–protein complex, while in the second step, a proximity-driven intermolecular crosslinking occurs. According to this scheme, the specific crosslinking reaction of a modular adaptor would be driven by the DNA recognition process only when the dissociation rate of the DNA complex is much higher than the rate constant for the alkylation reaction. In this study, as a proof of principle, a set of combinations for modular adaptors and their substrates were utilized to evaluate the reactions. Three types of modular adaptors consisting of a single type of self-ligating tag and three types of DNA binding proteins fulfill the kinetic requirements for the reaction of the self-ligating tag with a substrate and the dissociation of the DNA–protein complex. These modular adaptors actually undergo sequence-specific crosslinking reactions exclusively driven by the recognition of a specific DNA sequence. The design principle of sequence-specific modular adaptors based on the kinetic aspects of complex formation and chemical modification is applicable for developing recognition-driven selective modifiers for proteins and other biological macromolecules

The Beneficial Effects of Bisphosphonate-enoxacin on Cortical Bone Mass and Strength in Ovariectomized Rats

Osteoporosis is a major age-related bone disease characterized by low bone mineral density and a high risk of fractures. Bisphosphonates are considered as effective agents treating osteoporosis. However, long-term use of bisphosphonates is associated with some serious side effects, which limits the widespread clinical use of bisphosphonates. Here, we demonstrate a novel type of bone-targeting anti-resorptive agent, bisphosphonate-enoxacin (BE). In this study, ovariectomized rat model was established and treated with PBS, zoledronate (50 μg/kg) and different dose of BE (5 mg/kg and 10 mg/kg), respectively. The rats subjected to sham-operation and PBS treatment were considered as control group. Then, micro-computed tomography scanning, biomechanical tests, nano-indentation test and Raman analysis were used to compare the effects of zoledronate and BE on cortical bone mass, strength, and composition in ovariectomized rats. We found that both zoledronate and BE were beneficial to cortical bone strength. Three-point bending and nano-indentation tests showed that zoledronate- and BE-treated groups had superior general and local biomechanical properties compared to the ovariectomized groups. Interestingly, it seemed that BE-treated group got a better biomechanical property than the zoledronate-treated group. Also, BE-treated group showed significantly increased proteoglycan content compared with the zoledronate-treated group. We hypothesized that the increased bone strength and biomechanical properties was due to altered bone composition after treatment with BE. BE, a new bone-targeting agent, may be considered a more suitable anti-resorptive agent to treat osteoporosis and other bone diseases associated with decreased bone mass

AgentBench: Evaluating LLMs as Agents

Large Language Models (LLMs) are becoming increasingly smart and autonomous, targeting real-world pragmatic missions beyond traditional NLP tasks. As a result, there has been an urgent need to evaluate LLMs as agents on challenging tasks in interactive environments. We present AgentBench, a multi-dimensional evolving benchmark that currently consists of 8 distinct environments to assess LLM-as-Agent's reasoning and decision-making abilities in a multi-turn open-ended generation setting. Our extensive test over 27 API-based and open-sourced (OSS) LLMs shows that, while top commercial LLMs present a strong ability of acting as agents in complex environments, there is a significant disparity in performance between them and OSS competitors. We identify the typical reasons of failures in environments and LLMs, showing that poor long-term reasoning, decision-making, and instruction following abilities are the main obstacles for developing usable LLM agents. Training on code and high quality multi-turn alignment data could improve agent performance. Datasets, environments, and an integrated evaluation package for AgentBench are released at \url{https://github.com/THUDM/AgentBench}.Comment: 55 page

Leisure-Time Physical Activity before and during Pregnancy Is Associated with Improved Insulin Resistance in Late Pregnancy

A total of 83 third trimester pregnant women were recruited to examine the role of pre-pregnancy versus late-pregnancy physical activity on maternal insulin resistance. Principal component analysis plots demonstrated a distinction between the high and low Homeostatic Model Assessment for Insulin Resistance (HOMA-IR) groups. The variation was driven primarily by exercise prior to and during pregnancy. Specifically, higher levels of physical activity prior to pregnancy was associated with a lower HOMA-IR and is not modified by other variables. Women who were active prior to pregnancy were more active during pregnancy. These results suggest that being active before pregnancy may be a good strategy for mitigating the risk of insulin resistance during late pregnancy

GLM-130B: An Open Bilingual Pre-trained Model

We introduce GLM-130B, a bilingual (English and Chinese) pre-trained language model with 130 billion parameters. It is an attempt to open-source a 100B-scale model at least as good as GPT-3 (davinci) and unveil how models of such a scale can be successfully pre-trained. Over the course of this effort, we face numerous unexpected technical and engineering challenges, particularly on loss spikes and divergence. In this paper, we introduce the training process of GLM-130B including its design choices, training strategies for both efficiency and stability, and engineering efforts. The resultant GLM-130B model offers significant outperformance over GPT-3 175B (davinci) on a wide range of popular English benchmarks while the performance advantage is not observed in OPT-175B and BLOOM-176B. It also consistently and significantly outperforms ERNIE TITAN 3.0 260B -- the largest Chinese language model -- across related benchmarks. Finally, we leverage a unique scaling property of GLM-130B to reach INT4 quantization without post training, with almost no performance loss, making it the first among 100B-scale models and more importantly, allowing its effective inference on 4$\times$RTX 3090 (24G) or 8$\times$RTX 2080 Ti (11G) GPUs, the most affordable GPUs required for using 100B-scale models. The GLM-130B model weights are publicly accessible and its code, training logs, related toolkit, and lessons learned are open-sourced at \url{https://github.com/THUDM/GLM-130B/}.Comment: Accepted to ICLR 202

機能性ユニットを空間的に配置した生体高分子組織体による細胞内機能プローブの構築

京都大学新制・課程博士博士(エネルギー科学)甲第24252号エネ博第450号京都大学大学院エネルギー科学研究科エネルギー基礎科学専攻(主査)教授 森井 孝, 教授 片平 正人, 教授 佐川 尚学位規則第4条第1項該当Doctor of Energy ScienceKyoto UniversityDGA