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Microglia-mediated neuroinflammation contributes to major depressive disorder (MDD). Targeting microglia is a promising strategy for treating MDD. Patchouli alcohol (PA), an active component of Pogostemon cablin , has anti-inflammatory and neuroprotective effects. In this study, we investigate the microglia-mediated neurogenesis pathway in which PA ameliorates depressive-like behaviors in stress-induced animal model of depression. C57BL/6J male mice were exposed to chronic mild stress (CMS) for 4 weeks, then administered PA intraperitoneally at 10, 20 or 40 mg/kg once per day for 3 weeks. The antidepressant effects of PA were evaluated in the sucrose preference test, forced swimming test, and tail suspension test. Microglial phenotypes and activation of the NLRP3 inflammation were analyzed using RT-PCR, western blotting and immunofluorescence staining. Effects of PA on neurogenesis were analyzed in vitro and in vivo using immunofluorescence staining. Behavioral assessments showed that PA alleviated depressive-like behaviors in CMS-exposed mice. CMS induced microglial activation and pro-inflammatory profiles, which were blocked by PA treatment. PA attenuated the activation of NLRP3 inflammasome, leading to decreases in the levels of caspase-1, ASC, IL-1β, and IL-18 in the hippocampus of CMS-exposed mice. In primary microglia cultures, PA inhibited LPS-induced NLRP3 inflammasome activation. PA rescued inflammation-inhibited neurogenesis in vivo and in vitro. Our results suggest that PA inhibits the NLRP3 inflammasome and ameliorates microglia-mediated neurogenesis impairment, contributing to antidepressant effects. Thus, PA may be a novel treatment for inflammation-driven mental disorders. Patchouli alcohol inhibits NLRP3 inflammasome-mediated microglial activation, ameliorates neurogenesis impairment in the hippocampus, contributing to alleviate depressive-like behavior in CMS-exposed mice. [Display omitted] • Patchouli alcohol ameliorates depressive-like behaviors in mice exposed to chronic mild stress. • Patchouli alcohol attenuates stress-induced activation of the NLRP3 inflammasome in microglia. • Patchouli alcohol restores hippocampal neurogenesis in a mouse model of depression. [ABSTRACT FROM AUTHOR]

To better understand structure-function relationships, an X-ray crystal structure of the maltooligosaccharide-forming amylase from Bacillus stearothermophilus STB04 (Bst-MFA) with bound acarbose has been determined at 2.2 Å. The structure revealed a classical three-domain fold stabilized by four calcium ions, in which CaI–CaIII form an unprecedented linear metal triad in the interior of domain B. Catalytic residues are deduced to be two aspartic acids and one glutamic acid (Asp234, Glu264, Asp331), and the acarbose is bound to surrounding amino acid residues, mainly through extensive hydrogen bonds. Furthermore, analysis of the structure indicates the existence of at least 8 subsites in Bst-MFA, six glycone sites (−6, −5, −4, −3, −2, −1) and two aglycone sites (+1, +2). Subsite +3 remains to be further explored. Sugar-binding subsites contribute to further presentation of the oligosaccharide-binding mode, which explains the product specificity of Bst-MFA to some extent. In addition, we propose a mechanism by which maltooligosaccharide-forming amylases produce particular maltooligosaccharide products, a result different from that seen with typical α-amylases. Finally, the three-dimensional structure of Bst-MFA complexed with acarbose provides the basis for further studies, designed to increase product specificity. Unlabelled Image • The structure suggests the presence of at least 8 subsites in Bst-MFA. • The oligosaccharide-binding mode explains the product specificity of Bst-MFA. • The reaction mechanism of MFAses is distinct from that of more typical α-amylases. [ABSTRACT FROM AUTHOR]

Carbapenems and tigecycline are crucial antimicrobials for the treatment of gram-negative bacteria infections. Recently, a novel resistance-nodulation-division (RND) efflux pump gene cluster, tmexCD-toprJ, which confers resistance to tigecycline, has been discovered in animals and clinical isolates. It was reported that hospital sewage could act as a reservoir for gram-negative bacteria with high antimicrobial resistance genes. In this study, we analyzed 84 isolates of carbapenem-resistant gram-negative bacteria (CR-GNB) from hospital sewage, and identified five isolates of TMexCD-ToprJ-producing CR-GNB, including one Raoultella ornithinolytica isolate and four Pseudomonas spp. isolates. All these five isolates carried at least one carbapenem resistance gene and were resistant to multiple antibiotics. Multiple tmexCD-toprJ clusters were detected, including tmexC2D2-toprJ2 , tmexC3D3-toprJ3 , tmexC3.2D3.3-toprJ1b and tmexC3.2D3-toprJ1b. Among these clusters, the genetic construct of tmexC3.2D3-toprJ1b showed 2-fold higher minimum inhibitory concentration (MIC) of tigecycline than other three variants. In addition, it was found that the tmexCD-toprJ gene cluster was originated from Pseudomonas spp. and mainly located on Tn 6855 variants inserted in the same umuC -like genes on chromosomes and plasmids. This unit co-localized with bla IMP or bla VIM on IncHI5-, Inc pJBCL41 - and Inc pSTY -type plasmids in the five isolates of TMCR-GNB. The IncHI5- and Inc pSTY -type plasmids had the ability to conjugal transfer to E. coli J53 and P. aeruginosa PAO1, highlighting the potential risk of transfer of tmexCD-toprJ from Pseudomonas spp. to Enterobacterales. Importantly, genomic analysis showed that similar tmexCD-toprJ -harboring IncHI5 plasmids were also detected in human samples, suggesting transmission between environmental and human sectors. The emergence of TMCR-GNB from hospital sewage underscores the need for ongoing surveillance of antimicrobial resistance genes, particularly the novel resistance genes such as the tmexCD-toprJ gene clusters in the wastewater environment. [ABSTRACT FROM AUTHOR]

MYB genes play crucial roles in plant response to abiotic stress. However, the function of MYB genes in cotton during abiotic stress is less well elucidated. Here, we found an R2R3-type MYB gene, GhMYB44 , was induced by simulated drought (PEG6000) and ABA in three cotton varieties. After drought stress, the GhMYB44 -silenced plants showed substantial changes at the physiological level, including significantly increased malondialdehyde content and decreased SOD activity. Silencing the GhMYB44 gene increased stomatal aperture and water loss rate, reduced plant drought tolerance. Transgenic Arabidopsis thaliana over-expressed GhMYB44 (GhMYB44 -OE) enhanced resistance to mannitol-simulated osmotic stress. The stomatal aperture of the GhMYB44 -OE Arabidopsis was significantly smaller than those of the wild type (WT), and the GhMYB44 -OE Arabidopsis increased tolerance to drought stress. Transgenic Arabidopsis had higher germination rate under ABA treatment compared to WT, and the transcript levels of AtABI1 , AtPP2CA and AtHAB1 were suppressed in GhMYB44 -OE plants, indicating a potential role of GhMYB44 in the ABA signal pathway. These results showed that GhMYB44 acts as a positive regulator in plant response to drought stress, potentially useful for engineering drought-tolerant cotton. • GhMYB44 plays as a positive regulator in cotton response to drought stress. • GhMYB44 regulates stomatal aperture under drought treatment, thus enhancing the drought tolerance of cotton. • GhMYB44 regulates drought tolerance by mediating the activity of SOD and the transcription levels of PP2C genes. [ABSTRACT FROM AUTHOR]

Abstract: The volatile oil from Rhizoma Ligustici Chuanxiong Hort. (CXVO) is likely to be the mainly active ingredient of Chuangxiong in curing headache. In this study, oral administration of CXVO (45.0, 90.0, and 135.0μl/kg) to mice significantly elevated the pain threshold in the hot-plate test and reduced the number of abdominal writhing caused by acetic acid. CXVO (90.0 and 135.0μl/kg) not only reduced locomotor activity, but also prolonged the sleeping time induced by sodium pentobarbital (35mg/kg), and the number of mice with sleeping time over 1min by sodium pentobarbital (25mg/kg) was markedly enlarged by CXVO (45.0, 90.0, 135.0μl/kg) administration. The three doses of CXVO significantly increased the pain threshold of rabbits with headache due to hot radiation and the level of plasma ET of rats with headache due to nitroglycerin injection. Besides, for the nitroglycerin-induced headache rats, the c-fos gene expression in the brain stem and hypothalamus was remarkably inhibited and the level of plasma CGRP was reduced significantly after CXVO administration at both doses 90.0 and 135.0μg/kg. The latter dosage could also raise the level of plasma 5-HT markedly. The study suggests that CXVO acts probably as the active ingredient of Rhizoma Ligustici Chuanxiong Hort. (CX) on treating headache and has potential to be an agent for treating headache. [Copyright &y& Elsevier]

• The thermostable α-amylases can be obtained by building salt bridges. • The distribution, configuration and location of salt bridges vary in different amylases. • Appropriate salt bridges play crucial roles in both amylase stability and enzymatic function. The α-amylases are the most widely used industrial enzymes, and are particularly useful as liquifying enzymes in industrial processes based upon starch. Since starch liquefication is carried out at evaluated temperatures, typically above 60 °C, there is substantial demand for thermostable α -amylases. Most naturally occurring α -amylases exhibit moderate thermostability, so substantial effort has been invested in attempts to increase their thermostability. One structural feature that has the potential to increase protein thermostability is the introduction of salt bridges. However, not every salt bridge contributes to protein thermostability. The salt bridges in amylases have their characteristics in terms of distribution, configuration and location. The summary of these features helps to introduce new salt bridges based on the characteristics. This review focuses on salt bridges of α-amylases, both naturally present and introduced using mutagenesis. Its aim is to provide a bird's eye view of distribution, configuration, location of desirable salt bridges. [ABSTRACT FROM AUTHOR]

• Continuous AAC induces left ventricular remodeling by affecting multiple pathways, leading to chronic heart failure. • AWA alleviates left ventricular remodeling, including inhibition of myocardial hypertrophy, fibrosis, and cardiomyocyte apoptosis. • AWA alleviates chronic heart failure by promoting calcium ion balance in myocardial cells by decreasing the expression of RyR2 and SERCA2a. Many studies have shown the beneficial effects of aconite water-soluble alkaloid extract (AWA) in experimental models of heart disease, which have been ascribed to the presence of aconine, hypaconine, talatisamine, fuziline, neoline, and songorine. This study evaluated the effects of a chemically characterized AWA by chemical content, evaluated its effects in suprarenal abdominal aortic coarctation surgery (AAC)-induced chronic heart failure (CHF) in rats, and revealed the underlying mechanisms of action by proteomics. Rats were distributed into different groups: sham, model, and AWA-treated groups (10, 20, and 40 mg/kg/day). Sham rats received surgery without AAC, whereas model rats an AWA-treated groups underwent AAC surgery. after 8 weeks, the treatment group was fed AWA for 4 weeks, and body weight was assessed weekly. At the end of the treatment, heart function was tested by echocardiography. AAC-induced chronic heart failure, including myocardial fibrosis, cardiomyocyte hypertrophy, and apoptosis, was evaluated in heart tissue and plasma by RT-qPCR, ELISA, hematoxylin and eosin (H&E) staining, Masson's trichrome staining, TUNEL staining, and immunofluorescence staining of α-SMA, Col Ⅰ, and Col Ⅲ. Then, a proteomics approach was used to explore the underlying mechanisms of action of AWA in chronic heart failure. AWA administration reduced body weight gain, myocardial fibrosis, cardiomyocyte hypertrophy, and apoptosis, and rats showed improvement in cardiac function compared to model group. The extract significantly ameliorated the AAC-induced altered expression of heart failure markers such as ANP, NT-proBNP, and β-MHC, as well as fibrosis, hypertrophy markers MMP-2 and MMP-9, and other heart failure-related factors including plasma levels of TNF-α and IL-6. Furthermore, the extract reduced the protein expression of α-SMA, Col Ⅰ, and Col Ⅲ in the left ventricular (LV), thus inhibiting the LV remodeling associated with CHF. In addition, proteomics characterization of differentially expressed proteins showed that AWA administration inhibited left ventricular remodeling in CHF rats via a calcium signaling pathway, and reversed the expression of RyR2 and SERCA2a. AWA extract exerts beneficial effects in an AAC-induced CHF model in rats, which was associated with an improvement in LV function, hypertrophy, fibrosis, and apoptotic status. These effects may be related to the regulation of calcium signaling by the altered expression of RyR2 and SERCA2a. [ABSTRACT FROM AUTHOR]

• The new research progress on bioactivity and mechanism of grape seed extract. • Application of grape seed extract in the food industry. • Prospects of grape seed research. Grape seeds are rich in nutrients possessing high nutritional and medicinal value. Grape seed extract (GSE) mainly contains 15 phenolic compounds, such as (+)-catechin, (−)-epicatechin, proanthocyanidin, gallate, flavonols and others. Several studies on GSE and its components indicated that it has pharmacological attributes, such as antioxidation, anti-inflammation, anticancer, neuroprotection, lowering lipid, bacteriostatic, and reduced blood pressure. This article reviewed the research progress on the bioactivity of GSE and its application in foods in order to provide a reference for future studies on the development and utilization of grape seeds. [ABSTRACT FROM AUTHOR]

• Two non-reducing-end loop structures concern substrate orientation. • The loops accompanied MFA ps substrate-binding mode and product specificity. • Structural and action-mode differences among α-amylases support this proposal. The maltooligosaccharide-forming amylases (MFAses) degrade starch into maltooligosaccharides which potentially benefit human diet and grow popular in food processing, but little has been studied about their product specificity and structures. We focused on this topic and provide evidence through an X-ray crystal structure of the maltotetraose (G4)-forming amylase from Pseudomonas saccharophila STB07 (MFA ps), as well as co-crystal structures of MFA ps with G4 and with pseudo-maltoheptaose (pseudo-G7) determined at up to 1.1 Å resolution. G4 and pseudo-G7 occupy active cleft subsites −4 to −1 and −4 to +3 respectively. Binding induces conformational changes in the active sites except Asp193, working as the base catalyst. Comparison of the MFA ps structure with those of other α-amylases revealed obvious differences in the loop structures providing dominant interactions between protein and substrate in the non-reducing side of the active sites cleft. These structures at the non-reducing end may govern the G4 specificity of MFA ps and also be relevant to its exo -type action pattern. [ABSTRACT FROM AUTHOR]

Abstract: Ethnopharmacological relevance: The leaf of Malus toringoides (Rehd.) Hughes is a traditional folk medicine in Tibet, China, which is called “E Se” in Tibetan language. This original plant grows on snow mountains at an attitude of 3000 to 3700m. It is primarily used to treat hypertension, hyperlipidemia, hyperglycemia, indigestion and other diseases. This study aimed to evaluate the antidiabetic effect of flavonoids extracted from E Se (ESF) and to explore the potential mechanism in streptozotocin (STZ) or alloxan (ALX) induced diabetic mice and STZ-induced diabetic rats. Materials and methods: 72h after the establishment of a diabetic model, STZ or ALX induced diabetic mice and STZ-induced diabetic rats were treated daily with ESF at doses of 45, 90, 180mg/kg and 37.5, 75, 150mg/kg, respectively. Both mice and rats were fasted for 5h before administration and the blood glucose (BG) levels were tested 1h after treatment. Body weight was determined every other day. For STZ-induced rats, glycosylated hemoglobin (Hb1Ac), serum insulin and c-peptide, hepatic glycogen, superoxide dismutase (SOD) activity and malondialdehyde (MDA) levels in liver were assessed on the fourth day after BG level detection. Results: Compared with the model group, the general behavior of mice treated with ESF (90, 180mg/kg) and rats treated with ESF (75, 150mg/kg) became better and BG levels were significantly reduced (P<0.05). Significant decrease (P<0.05) in Hb1Ac level was observed in ESF-treated rats compared with diabetic rats. Significant increase (P<0.05 ) in serum insulin and c-peptide were detected in ESF-treated rats. The treatment also significantly (P<0.05) elevated SOD activity and reduced MDA level in the liver of diabetic rats. Besides, ESF 150mg/kg had a trend of rising hepatic glycogen content of diabetic rats. Conclusions: The findings of this study suggest that flavonoids from the Malus toringoides (Rehd.) Hughes leaves may possess an antidiabetic activity in animals with established diabetes. [Copyright &y& Elsevier]

The efficiency of enzymatic cyclodextrin production using cyclodextrin glycosyltransferases (CGTases) is limited by product inhibition. In this study, maltose binding site 2 (MBS2) of the β-CGTase from Bacillus circulans STB01 was modified to decrease product inhibition. First, two point mutants were prepared at position 599 (A599V and A599N). Then, two double mutants incorporating alanine at position 633 (A599N/Y633A and A599V/Y633A) were prepared. Finally, the entire MBS2 region was replaced by that of the α-CGTase from Paenibacillus macerans JFB05-01 to form multipoint mutant MBS2 β → α. All five mutants exhibited mixed-type product inhibition, although both the competitive and uncompetitive components of this inhibition were decreased. The total cyclization activities of A599N, A599V and A599V/Y633A were 15.6%, 76.8% and 70.9% lower than that of the wild-type, respectively, while that of A599N/Y633A was 22.4% higher. Among the mutants, only MBS2 β → α showed catalytic efficiency (k cat / K m) comparable with that of the wild-type. Moreover, A599N, A599N/Y633A and MBS2 β → α produced cyclodextrin yields 13.1%, 15.8% and 19.7% greater than that of the wild-type, respectively. These results suggest that A599N, A599N/Y633A and MBS2 β → α may be more suitable than the wild-type for cyclodextrin production. [ABSTRACT FROM AUTHOR]

• The branched structure of short-clustered maltodextrin (SCMD) was observed. • SCMD-protecting yeast had more integral microstructures and higher viability. • The cell membrane fluidity of SCMD-protecting yeast was enhanced. • Protected yeast had a higher relative abundance of unsaturated glycerophospholipid. • SCMD existence promoted the mobility of lipid bilayer at 250 K. Cryoprotective polysaccharides have been extensively explored. We found that short-clustered maltodextrin (SCMD) effectively increased yeast viability. But the specific mechanism of SCMD affecting yeast is still not clear. Here, we detailedly analyze the effects of SCMD addition on cell membrane homeostasis. Firstly, the high-branched structure of SCMD was observed, and the microstructure of SCMD-protecting yeast was more integral. Analysis of membrane physicochemical property and glycerophospholipid metabolism demonstrated the fluidity of cell membrane of SCMD-protecting yeast was enhanced, as the relative abundances of glycerophospholipids with unsaturated acyl chains increased in comparison to Control yeast. Further, molecular dynamics simulations found that simplified SCMD could form more H-bonds with water molecules around lipid bilayers at 250 K to promote the mobility of lipid bilayers. Therefore, the hypothesis of "SCMD existence promotes the membrane fluidity under ice-crystal stress during frozen storage and helps maintain cell membrane homeostasis after thawing, increasing the thawed yeast viability" is proposed. [ABSTRACT FROM AUTHOR]