Bioactivities,Mechanisms,Production,and Potential Application of Bile Acids in Preventing and Treating Infectious Diseases

Infectious diseases are a global public health problem,with emerging and re-emerging infectious diseases on the rise worldwide.Therefore,their prevention and treatment are still major challenges.Bile acids are common metabolites in both hosts and microorganisms that play a significant role in controlling the metabolism of lipids,glucose,and energy.Bile acids have historically been utilized as first-line,valuable therapeutic agents for related metabolic and hepatobiliary diseases.Notably,bile acids are the major active ingredients of cow bezoar and bear bile,which are commonly used traditional Chinese medicines(TCMs)with the therapeutic effects of clearing heat,detoxification,and relieving wind and spasm.In recent years,the promising performance of bile acids against infectious diseases has attracted attention from the scientific community.This paper reviews for the first time the biological activities,possible mechanisms,production routes,and potential applications of bile acids in the treatment and prevention of infectious diseases.Compared with previous reviews,we comprehensively summarize existing studies on the use of bile acids against infectious diseases caused by pathogenic microorganisms that are leading causes of global morbidity and mortality.In addition,to ensure a stable supply of bile acids at affordable prices,it is necessary to clarify the biosynthesis of bile acids in vivo,which will assist scientists in elucidating the accumulation of bile acids and discovering how to engineer various bile acids by means of chemosynthesis,biosynthesis,and chemoenzymatic synthesis.Finally,we explore the current challenges in the field and recommend a development strategy for bile-acid-based drugs and the sustainable production of bile acids.The presented studies suggest that bile acids are potential novel therapeutic agents for managing infectious diseases and can be artificially synthesized in a sustainable way.

Portal hypertension in patients with nonalcoholic fatty liver disease:Current knowledge and challenges

Portal hypertension(PH)has traditionally been observed as a consequence of significant fibrosis and cirrhosis in advanced non-alcoholic fatty liver disease(NAFLD).However,recent studies have provided evidence that PH may develop in earlier stages of NAFLD,suggesting that there are additional pathogenetic mechanisms at work in addition to liver fibrosis.The early development of PH in NAFLD is associated with hepatocellular lipid accumulation and ballooning,leading to the compression of liver sinusoids.External compression and intraluminal obstacles cause mechanical forces such as strain,shear stress and elevated hydrostatic pressure that in turn activate mechanotransduction pathways,resulting in endothelial dysfunction and the development of fibrosis.The spatial distribution of histological and functional changes in the periportal and perisinusoidal areas of the liver lobule are considered responsible for the pre-sinusoidal component of PH in patients with NAFLD.Thus,current diagnostic methods such as hepatic venous pressure gradient(HVPG)measurement tend to underestimate portal pressure(PP)in NAFLD patients,who might decompensate below the HVPG threshold of 10 mmHg,which is traditionally considered the most relevant indicator of clinically significant portal hypertension(CSPH).This creates further challenges in finding a reliable diagnostic method to stratify the prognostic risk in this population of patients.In theory,the measurement of the portal pressure gradient guided by endoscopic ultrasound might overcome the limitations of HVPG measurement by avoiding the influence of the pre-sinusoidal component,but more investigations are needed to test its clinical utility for this indication.Liver and spleen stiffness measurement in combination with platelet count is currently the best-validated non-invasive approach for diagnosing CSPH and varices needing treatment.Lifestyle change remains the cornerstone of the treatment of PH in NAFLD,together with correcting the components of metabolic syndrome,using nonselective beta blockers,whereas emerging candidate drugs require more robust confirmation from clinical trials.

Time course and mechanism of brain oxidative stress and damage for redox active and inactive transition metals overload

The objective of this work was to study the in vivo time course of biochemical processes of oxidative damage in the brain of Sprague-Dawley rats that received an acute overload of the redox active metals iron(Fe)and copper(Cu),and the redox inactive cobalt(Co)and nickel(Ni).Oxidative stress indicators(phospholipid and protein oxidation),glutathione(GSH),antioxidant enzymes and NADPH oxidase activities,and the plasma inflam-matory cytokine(IL-6)were measured.The results showed that in brain oxidative mechanisms for both sets of metal are different,however in both cases are irreversible.The mechanism for Fe and Cu oxidative damage is mediated by the generation of the free radical hydroxyl(Fenton reaction and homolytic cleavage of hydroperoxides).Two events of antioxidant protection prior to oxidation of phospholipids and proteins by Fe and Cu are considered.The first process is the use of GSH and the second is the increased activity of the Cu,Zn-SOD and catalase enzymes.The oxidative mechanism for metal redox inactive is the consumption of GSH,NADPH oxidase activation and inflammatory response mediated by IL-6.Co increased protein oxidation as a result of the inflammatory process.Ni produced increments of phospholipid oxidation and SOD activity.

New Green Synthesis and Antineoplastic Activity of Bis (3-Arylimidazolidinyl-1) Methanes

A new green synthesis and anti-tumor activity of the series of bis (3-arylimidazolidinyl-1) methanes 1 - 6 are described. The compounds were synthesized from the corresponding N-arylethylenediamine and trioxane as sources of formaldehyde and the reactions were performed in heterogeneous phase catalyzed by an acidic ion-exchange resin (Amberlyst 15). The compounds were tested with the Sulforhodamine B assay according to the protocol of the National Cancer Institute for several cell lines. The results were expressed as percentage inhibition of growth cell in comparison with the full growth of the cells without treatment. Cytotoxicity on normal cells using the Annexing-PI staining and flow cytometry has been evaluated. The parent compound, bis(3-phenylimidazolidinyl-1)methane 1 and the monohalogenated derivatives 4-chlorophenyl 3 and 3-bromophenyl 5 showed antineoplastic activity, 60%, 82% and 89% inhibition growth cell respectively on the human colon cell line (HCT116). The 4-tolyl derivative 6 presented inhibitory activity (73% inhibition of growth cell) on human lung adenocarcinoma cell line (A549) and 62% on human mammary cell line MCF-7.

Increased Levels of Hyaluronic Acid in Bronchoalveolar Lavage from Patients with Interstitial Lung Diseases, Relationship with Lung Function and Inflammatory Cells Recruitment

Purpose: Interstitial Lung Diseases (ILD) are characterized by inflammation and fibrosis. It described the role of hyaluronic acid (HA) as an immune-regulator. It is not known if HA contributes to the recruitment of inflammatory cells associated with ILD. If this hypothesis was correct, then concentrations of HA in bronchoalveolar lavage (BAL) should correlate with the severity of ILD. Methods: We collected BAL from 22 ILD patients and 15 control subjects. We determined HA and cytokine levels by ELISA. In vitro chemotaxis assays were performed by using a transwell system. Results: We found that ILD patients showed a significant increase in HA, IL-6 levels and the amount of cells in BAL compared to control subjects. We detected a significant positive correlation between HA and IL-6 levels (r = 0.53 and p In vitro, HA induced migration of macrophages and monocytes through a CD44-dependent process. BAL from patients with ILD stimulated macro-phage migration and this was abrogated by hyaluronidase. Conclusions: Our results support the hypothesis that HA contributes to the recruitment of monocytes towards the alveolar space, leading to exacerbation of lung inflammation in ILD patients.

Study of the Potential Value of flex affinis （Aquifoliaceae） as a Novel Source for the Food and Pharmaceutical Industries

llex paraguariensis St. Hilaire （Aquifoliaceae） is processed industrially to produce the commercial product ＂yerba mate＂ which is used as a tea-like beverage. It is one of the most commercialized plants of South America. It is exported to the US, Europe and Asia as vegetal drug or extracts used in complementary and alternative medicine and in formulations for functional foods due to its properties as a CNS stimulant, diuretic, weight reducing, antioxidant and antihypercholesterolemic, among others, llex affinis grows in the same habitat and is used as substitute or adulterant ofI. paraguariensis. This species was never investigated before. The objective of this work was to assess the phytochemical composition and to determine the pharmacological activity, according with the major compounds present in it. The results showed small quantities of caffeine and theobromine, but a considerable amount of polyphenols, especially chlorogenic acid and isochlorogenic acid. I. affinis extracts presented scavenging activity on free radical DPPH in a concentration-dependent manner. Antiproliferative action on lymphoma cell line exerting both cytostatic and cytotoxic activities was also demonstrated.

Comparative Antiproliferative Action of Two Extracts from <i>Tilia x viridis</i>on Normal and Tumoral Lymphocytes: Rela-tionship with Antioxidant Activity

Tilia species have been used in Asia, Europe and in America to treat anxiety and also for the treatment of colds and inflammation. The oxygen reactive species (ROS) (hydrogen peroxide (H2O2) and the superoxide anion (O2) are involve in the balance cell proliferation/death in lymphocytes. It was reported the presence of flavonoids in Tilia species which possess antioxidant properties. The aim of this study was to determine comparatively the effect of an aqueous (AE) and ethanol (E) extract from Tilia x viridis, on the proliferation of tumoral and normal concanavalin A stimulated murine lymphocytes in relation to antioxidant activities such as peroxidase (Px), catalase (CAT) and superoxide dismutase (SOD) activities involves in H2O2 modulation. Also a phytochemical pattern of the two extracts in relation to flavonoids content was determined. Both extracts presented antiproliferative action on both type of lymphocytes but E was more selective on the tumoral lymphocytes inhibition (EC50 (μg/ml, Mean ±SEM) (tumoral): 50 ± 4;EC50;(normal lymphocytes): 323 ± 20);this action was related to a high polyphenols content (150 ± 10 mg/g extract) and high “per se” SOD and low Px activities. In conclusion, the extracts could be a source of antioxidant compounds which contribute to a selective antiproliferative action on tumoral cells, acting through the modulation of H2O2 levels.

The role of microglia in depression

According to studies,neuroinflammation is increasingly being linked to the development of major depressive disorder(MDD).In response to inflammatory stimuli,brain microglia,which are immune cells,can change into reactive states.Because of this,microglia play an essentiall role in the early stages of neuroinflammation.Experiments have shown that microglia are able to detect infected or damaged cells,which then activates a cytotoxic response that further exacerbates the harm to brain cells.It has been proven that microglia are quite good at recognizing infections and damaged cells.Microglia,on the other hand,have been found to respond in a number of ways to injury and may even help regenerate damaged tissues.Chronic activation of microglia has been observed in persons with MDD.Deficits in neuroplasticity have been linked to depression,and recent studies show that this may be related to changes in microglia shape and function brought on by either excessive inflammatory activity or the natural aging process.Changing the phenotype of microglia by regulation of inflammatory pathways may be necessary for harnessing neuroinflammation in MDD.Recent research has linked several microglial phenotypes to individual metabolic pathways,showing that energy metabolism plays a pivotal role in coordinating microglial activity.In this study,we investigate whether or not traditional pro-inflammatory,anti-inflammatory,and metabolic pathways in microglia can be used as novel therapeutic routes for regulating neuroinflammation in brain diseases.The focus of this essay is on MDD,although we will also discuss related mental health issues.

Microbiota and depression an update

The highest rates of morbidity and impairment related to gastrointestinal difficulties are associated with depression,which is associated with the highest rates of all mental disorders.It has been demonstrated that the composition of an individual's gut microbiome plays a significant part in determining that person's risk of developing depression.According to the hypothesis known as the gut-brain axis,there may be a connection between the intestinal microbial system and the brain.In recent years,it has been common practice to treat disorders by concentrating on the bacteria that are found in the digestive tract(for instance,by making use of probiotics)and incorporating the gut-brain axis mechanism.Our research revealed a remarkable association between the composition of the bacteria in the stomach and the incidence of depression.Alterations in the structure of the microbiota system in the gut could possibly have direct and special impacts on the rise in the prevalence of depression.This study investigated the mechanisms underlying the two-way communication in the gut-brain axis,including the current techniques of relieving symptoms and antidepressant medicines that are related to gut microbiota.An increase in the amount of research into the medical potential of probiotics has led to a rapid expansion of the field of probiotics over the past few decades.Numerous preclinical and clinical studies have established that the therapeutic effects of probiotics-mediated microbiota remodeling near the microbiota-gut-brain axis(MGBA)are present.These studies were conducted near one another.However,the potential effects of probiotics on numerous mental illnesses,which have been proved in vivo and in vitro research,have set the ground for the translation of preclinical models to humans,which is still in its infancy.

转录因子HNF1A、HNF4A和FOXA2调节肝细胞蛋白质N-糖基化

Hepatocyte nuclear factor 1 alpha(HNF1A),hepatocyte nuclear factor 4 alpha(HNF4A),and forkhead box protein A2(FOXA2)are key transcription factors that regulate a complex gene network in the liver,cre-ating a regulatory transcriptional loop.The Encode and ChIP-Atlas databases identify the recognition sites of these transcription factors in many glycosyltransferase genes.Our in silico analysis of HNF1A,HNF4A.and FOXA2 binding to the ten candidate glyco-genes studied in this work confirms a significant enrich-ment of these transcription factors specifically in the liver.Our previous studies identified HNF1A as a master regulator of fucosylation,glycan branching,and galactosylation of plasma glycoproteins.Here,we aimed to functionally validate the role of the three transcription factors on downstream glyco-gene transcriptional expression and the possible effect on glycan phenotype.We used the state-of-the-art clus-tered regularly interspaced short palindromic repeats/dead Cas9(CRISPR/dCas9)molecular tool for the downregulation of the HNF1A,HNF4A,and FOXA2 genes in HepG2 cells-a human liver cancer cell line.The results show that the downregulation of all three genes individually and in pairs affects the transcrip-tional activity of many glyco-genes,although downregulation of glyco-genes was not always followed by an unambiguous change in the corresponding glycan structures.The effect is better seen as an overall change in the total HepG2 N-glycome,primarily due to the extension of biantennary glycans.We propose an alternative way to evaluate the N-glycome composition via estimating the overall complexity of the glycome by quantifying the number of monomers in each glycan structure.We also propose a model showing feedback loops with the mutual activation of HNF1A-FOXA2 and HNF4A-FOXA2 affecting glyco-genes and protein glycosylation in HepG2 cells.

Endoscopic ultrasound guided fine needle aspiration and useful ancillary methods

The role of endoscopic ultrasound(EUS) in evaluating pancreatic pathology has been well documented from the beginning of its clinical use. High spatial resolution and the close proximity to the evaluated organs within the mediastinum and abdominal cavity allow detection of small focal lesions and precise tissue acquisition from suspected lesions within the reach of this method. Fine needle aspiration(FNA) is considered of additional value to EUS and is performed to obtain tissue diagnosis. Tissue acquisition from suspected lesions for cytological or histological analysis allows, not only the differentiation between malignant and non-malignant lesions, but, in most cases, also the accurate distinction between the various types of malignant lesions. It is well documented that the best results are achieved only if an adequate sample is obtained for further analysis, if the material is processed in an appropriate way, and if adequate ancillary methods are performed. This is a multi-step process and could be quite a challenge in some cases. In this article, we discuss the technical aspects of tissue acquisition by EUS-guided-FNA(EUS-FNA), as well as the role of an on-site cytopathologist, various means of specimen processing, and the selection of the appropriate ancillary method for providing an accurate tissue diagnosis and maximizing the yield of this method. The main goal of this review is to alert endosonographers, not only to the different possibilities of tissue acquisition, namely EUS-FNA, but also to bring to their attention the importance of proper sample processing in the evaluation of various lesions in the gastrointestinal tract and other accessible organs. All aspects of tissue acquisition(needles, suction, use of stylet, complications, etc.) have been well discussed lately. Adequate tissue samples enable comprehensive diagnoses, which answer the main clinical questions, thus enabling targeted therapy.

Importance of genetic polymorphisms in liver transplantation outcomes

Although,liver transplantation serves as the only curative treatment for patients with end-stage liver diseases,it is burdened with complications,which affect survival rates.In addition to clinical risk factors,contribution of recipient and donor genetic prognostic markers has been extensively studied in order to reduce the burden and improve the outcomes.Determination of single nucleotide polymorphisms(SNPs)is one of the most important tools in development of personalized transplant approach.To provide a better insight in recent developments,we review the studies published in the last three years that investigated an association of recipient or donor SNPs with most common issues in liver transplantation:Acute cellular rejection,development of new-onset diabetes mellitus and non-alcoholic fatty liver disease,hepatocellular carcinoma recurrence,and tacrolimus concentration variability.Reviewed studies confirmed previously established SNP prognostic factors,such as PNPLA3 rs738409 for nonalcoholic fatty liver disease development,or the role of CYP3A5 rs776746 in tacrolimus concentration variability.They also identified several novel SNPs,with a reasonably strong association,which have the potential to become useful predictors of post-transplant complications.However,as the studies were typically conducted in one center on relatively low-to-moderate number of patients,verification of the results in other centers is warranted to resolve these limitations.Furthermore,of 29 reviewed studies,28 used gene candidate approach and only one implemented a genome wide association approach.Genome wide association multicentric studies are needed to facilitate the development of personalized transplant medicine.

Renaldopaminergic system:Pathophysiological implications andclinical perspectives

Fluid homeostasis, blood pressure and redox balance in the kidney are regulated by an intricate interaction between local and systemic anti-natriuretic and natriuretic systems. Intrarenal dopamine plays a central role on this interactive network. By activating specifc receptors, dopamine promotes sodium excretion and stimulates anti-oxidant and anti-inflammatory pathways. Different pathological scenarios where renal sodium excretion is dysregulated, as in nephrotic syndrome, hypertension and renal infammation, can be associated with impaired action of renal dopamine including alteration in biosynthesis, dopamine receptor expression and signal transduction. Given its properties on the regulation of renal blood fow and sodium excretion, exogenous dopamine has been postulated as a potential therapeutic strategy to preventrenal failure in critically ill patients. The aim of this review is to update and discuss on the most recent findings about renal dopaminergic system and its role in several diseases involving the kidneys and the potential use of dopamine as a nephroprotective agent.

月经周期中免疫球蛋白G N-糖基化的周期性变化

Immunoglobulin G(IgG)is the most abundant plasma glycoprotein and a prominent humoral immune mediator.Glycan composition affects the affinity of IgG to ligands and consequent immune responses.The modification of IgG N-glycosylation is considered to be one of the various mechanisms by which sex hormones modulate the immune system.Although the menstrual cycle is the central sex hormonerelated physiological process in most women of reproductive age,IgG N-glycosylation dynamics during the menstrual cycle have not yet been investigated.To fill this gap,we profiled the plasma IgG Nglycans of 70 healthy premenopausal women at 12 time points during their menstrual cycles(every 7 days for 3 months)using hydrophilic interaction ultra-performance liquid chromatography(HILIC-UPLC).We observed cyclic periodic changes in the N-glycosylation of IgG in association with the menstrual cycle phase and sex hormone concentration in plasma.On the integrated cohort level,the modeled average menstrual cycle effect on the abundance of IgG N-glycosylation traits was low for each trait,with the highest being 1.1%for agalactosylated N-glycans.However,intrapersonal changes were relatively high in some cases;for example,the largest difference between the minimum and maximum values during the menstrual cycle was up to 21%for sialylated N-glycans.Across all measurements,the menstrual cycle phase could explain up to 0.72%of the variation in the abundance of a single IgG glycosylation trait of monogalactosylation.In contrast,up to 99%of the variation in the abundance of digalactosylation could be attributed to interpersonal differences in IgG N-glycosylation.In conclusion,the average extent of changes in the IgG N-glycopattern that occur during the menstrual cycle is small;thus,the IgG N-glycoprofiling of women in large sample-size studies can be performed regardless of menstrual cycle phase.

流感与COVID-19患者的免疫球蛋白G糖基化差异

The essential role of immunoglobulin G(IgG)in immune system regulation and combatting infectious diseases cannot be fully recognized without an understanding of the changes in its N-glycans attached to the asparagine 297 of the fragment crystallizable(Fc)domain that occur under such circumstances.These glycans impact the antibody stability,half-life,secretion,immunogenicity,and effector functions.Therefore,in this study,we analyzed and compared the total IgG glycome—at the level of individual glycan structures and derived glycosylation traits(sialylation,galactosylation,fucosylation,and bisecting Nacetylglucosamine(GlcNAc))—of 64 patients with influenza,77 patients with coronavirus disease 2019(COVID-19),and 56 healthy controls.Our study revealed a significant decrease in IgG galactosylation,sialylation,and bisecting GlcNAc(where the latter shows the most significant decrease)in deceased COVID19 patients,whereas IgG fucosylation was increased.On the other hand,IgG galactosylation remained stable in influenza patients and COVID-19 survivors.IgG glycosylation in influenza patients was more time-dependent:In the first seven days of the disease,sialylation increased and fucosylation and bisecting GlcNAc decreased;in the next 21 days,sialylation decreased and fucosylation increased(while bisecting GlcNAc remained stable).The similarity of IgG glycosylation changes in COVID-19 survivors and influenza patients may be the consequence of an adequate immune response to enveloped viruses,while the observed changes in deceased COVID-19 patients may indicate its deviation.

Detection of presumed genes encoding beta-lactamases by sequence based screening of metagenomes derived from Antarctic microbial mats

Analysis of environmental samples for bacterial antibiotic resistance genes may have different objectives and analysis strategies. In some cases, the purpose was to study diversity and evolution of genes that could be grouped within a mechanism of antibiotic resistance. Different protocols have been designed for detection and confirmation that a functional gene was found. In this study, we present a sequence-based screening of candidate genes encoding beta-lactamases in 14 metagenomes of Antarctic microbial mats. The samples were obtained from different sites, representing diverse biogeographic regions of maritime and continental Antarctica. A protocol was designed based on generation of Hidden Markov Models from the four beta-lactamase classes by Ambler classification, using sequences from the Comprehensive Antibiotic Resistance Database (CARD). The models were used as queries for metagenome analysis and recovered contigs were subsequently annotated using RAST. According to our analysis, 14 metagenomes analyzed contain A, B and C beta-lactamase genes. Class D genes, however, were identified in 11 metagenomes. The most abundant was class C (46.8%), followed by classes B (35.5%), A (14.2%) and D (3.5%). A considerable number of sequences formed clusters which included, in some cases, contigs from different metagenomes. These assemblies are clearly separated from reference clusters, previously identified using CARD beta-lactamase sequences. While bacterial antibiotic resistance is a major challenge of public health worldwide, our results suggest that environmental diversity of beta-lactamase genes is higher than that currently reported, although this should be complemented with gene function analysis.