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Aims: Probiotics are known to maintain intestinal homeostasis through the regulation of the immune response of the host. Hence, the role of histone modifications as epigenetic agents on immune modulations by potential probiotic bacteria has been investigated., Methods and Results: Human colonic epithelial cells (Caco-2) pre-treated with class I histone deacetylase (HDAC) specific inhibitor, MS-275, were incubated either with potential probiotic bacteria (Limosilactobacillus fermentum MTCC 5898 and Lacticaseibacillus rhamnosus MTCC 5897) or Escherichia coli (ATCC 14948) as an inflammatory agent. Initially, transcriptional expression of potential immune-related genes (IL-6, IL-8, and hBD-2) was analyzed using RT-qPCR, and later H3 histone acetylation (H3Ac) at the promoter region of these genes was confirmed with a chromatin immunoprecipitation (ChIP) assay respectively. Potential probiotic L. fermentum (MTCC 5898) significantly suppressed (P < 0.05) the inhibitor-mediated elevated expression of immune-related genes while another strain L. rhamnosus (MTCC 5897), did not influence these gene expression results. In contrast, as an inflammatory agent, E. coli (ATCC 14948) synergistically augmented the expression of immune-related genes. Later, ChIP analysis confirmed the occurrence of H3 acetylation at these genes' promoter regions, which was directly related to the transcriptional activity of host epithelial cells stimulated by L. fermentum and E. coli, respectively. But in the case of L. rhamnosus, MTCC 5897, acetylation did not follow the transcription pattern and potentiated H3Ac on the promoter regions of these genes., Conclusions: Potential probiotics used in the study were found to regulate the immune response of host cells through histone acetylation in a strain-specific manner., Significance and Impact of Study: Occurrence of probiotic-mediated regulation of immune genes by H3 acetylation in a strain-specific manner., (© The Author(s) 2022. Published by Oxford University Press on behalf of Applied Microbiology International.)

The epigenome of an organism is as important as the genome for the normal development and functioning of an individual. The human epigenome can be affected by various environmental factors including nutrients, microbiota and probiotics through epigenetic modifiers and mediates various health-promoting effects. The present study was aimed to explore the temporal changes in DNA and histone modifiers (DNMT1, TET2, p300, HDAC1, KMT2A, KDM5B, EzH2 and JMJD3) in intestinal epithelial cells (Caco-2) by probiotic lactobacilli (Limosilactobacillus fermentum MTCC 5898 and Lacticaseibacillus rhamnosus MTCC 5897) in comparison to opportunistic commensal pathogen Escherichia coli (ATCC 14849). Cells were treated separately with probiotic strains and E. coli for different durations and temporal changes in gene expression among DNA and histone modifiers were measured. Time-dependent studies showed that L. fermentum enhanced the transcription of epigenetic modifiers at 12 h of treatment (P < 0.05) contrary to E. coli which reduced the expression of these genes during the same duration of treatment. On the other hand, probiotic L. rhamnosus was not able to induce any significant changes in gene expression of these modifiers. Furthermore, during the exclusion of E. coli by L. fermentum, the probiotic was found to resist the changes made by E. coli in the transcription of some of the epigenetic modifiers. Thus, it is concluded that the probiotics modulated the mRNA expression of DNA and histone modifiers contrarily to E. coli in a strain-specific manner., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

The probiotic extracellular matrix components (ECM) have been considered as an important factor in eliciting the beneficial roles of the bacteria. The study involved the growth phase-dependent extraction of the surface layer protein (SLP) and cell-bound exopolysaccharide (EPS-b) from novel Limosilactobacillus fermentum (MTCC 5898). Both SLP and EPS-b were optimally extracted at the late logarithmic phase of the bacteria upon 8 h of incubation. Furthermore, the adhesive, immunomodulatory, and anti-oxidative potential of the extracted components were evaluated using in vitro models. The major role of SLP was evidenced on bacterial adhesion to mucin and was related to its hydrophobic character. Under in vitro conditions, no effect of SLP and EPS-b was observed on the proliferation of murine splenocytes; however, both the components stimulated the phagocytosis of murine peritoneal macrophages at varying concentrations. Furthermore, all the components exhibited strong radical scavenging, chelating, and reducing potential with increasing concentration. Therefore, the ECM components of L. fermentum exhibited a variable biofunctional effect, providing crucial information to enable its further use as functional foods and overcome the challenges posed by probiotics., (© 2021. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

The epigenome is an overall epigenetic state of an organism, which is as important as that of the genome for normal development and functioning of an individual. Epigenetics involves heritable but reversible changes in gene expression through alterations in DNA methylation, histone modifications and regulation of non-coding RNAs in cells, without any change in the DNA sequence. Epigenetic changes are owned by various environmental factors including pollution, microbiota and diet, which have profound effects on epigenetic modifiers. The bioactive compounds present in the diet mainly include curcumin, resveratrol, catechins, quercetin, genistein, sulforaphane, epigallocatechin-3-gallate, alkaloids, vitamins, and peptides. Bioactive compounds released during fermentation by the action of microbes also have a significant effect on the host epigenome. Besides, recent studies have explored the new insights in vitamin's functions through epigenetic regulation. These bioactive compounds exert synergistic, preventive and therapeutic effects when combined as well as when used with chemotherapeutic agents. Therefore, these compounds have potential of therapeutic agents that could be used as "Epidrug" to treat many inflammatory diseases and various cancers where chemotherapy results have many side effects. In this review, the effect of diet derived bioactive compounds through epigenetic modulations on in vitro and in vivo models is discussed.

This study investigated the physicochemical characteristics and antioxidative role of novel acidic cell-bound exopolysaccharide (EPS-b) from probiotic Limosilactobacillus fermentum (MTCC 5898) and gained an insight into the structure-function relationship. The physicochemical analysis of EPS-b isolated by ultrasonication method revealed a heteropolysaccharide molecule with an average MW of 96.97 kDa composed of glucose and galactose subunits present in random-coiled conformation. Fourier transform infrared (FTIR) and nuclear magnetic resonance (NMR) analyses further supported the observation and indicated the presence of α-(1 → 6) linkages. The analyses implicated the significant influence of structural features on the antioxidative activity of EPS-b by showing remarkable ABTS scavenging, reducing, and metal chelating potential with increasing concentration. Besides, the EPS-b by its scavenging potential also maintained the oxidative balance in the Caco-2 cells under oxidative stress and preserved the cellular antioxidative defense system (CAT, GPx, SOD, HO1 , and GCLC ) at the basal level.

Cardiovascular disease is predicted to be the largest cause of death and disability in India by 2020. Hypertension (HT), one of the main contributing factors, presents a significant public health burden. Inability to achieve adequate blood pressure (BP) control results in uncontrolled hypertension (UHT). The prevalence of UHT is high in India, with only about 9-20% of patients achieving target BP goals. Presently, there are no guidelines specific to UHT, which if left uncontrolled can lead to resistant HT, chronic kidney disease and other complications of HT. A multidisciplinary panel, comprising of specialists in cardiology, nephrology and internal medicine, was convened to address the diagnosis and management of UHT in the Indian population. The panel identified key points concerning UHT and discussed management recommendations in the Indian clinical setting.

Antibiotic mediated therapies target the growth-related processes of the pathogen hence imparting a strong selection pressure on the pathogen to develop antibiotic resistance. Recently anti-virulence strategies have gained lots of attention amongst the scientific community, wherein instead of inhibiting the normal growth of pathogens, it interferes with the regulation of virulence factors of the pathogens and impede their pathogenesis. In Pseudomonas aeruginosa, the virulence mechanism accountable for various types of infections in humans depends on N-acyl homoserine lactone (AHL) mediated quorum sensing. So quenching of these molecules, pose as a promising tool against P. aeruginosa pathogenesis. Lactic acid bacteria cell-free supernatant (acidic and neutralized) were evaluated in quorum quenching of P. aeruginosa PAO1 (MTCC 3541) after their initial screening for anti-biofilm potential against this pathogen.Though the reduction in biofilm formation with acidic and neutralized supernatants of lactic acid bacteria revealed strain specific response but acidic fractions showed much stronger (P ≤ 0.05) inhibition of biofilm irrespective of the type of challenge given to P. aeruginosa with lactic acid bacteria. The acidic fraction of supernatants (L. lactis, L. rhamnosus and L. fermentum) not only showed a significant reduction (P ≤ 0.05) in auto-inducer AHL levels but also diminished elastase activity which was among important virulence characters directly controlled by the quorum sensing signaling. Moreover, significant decrease (P ≤ 0.05) in mRNA expression of lasI and rhlI in presence of acidic fractions of lactic acid bacterial supernatants further confirmed the quorum quenching process in P. aeruginosa., Competing Interests: Declaration of competing interest The authors declare that they have no conflict of interest regarding this study., (Copyright © 2020. Published by Elsevier Ltd.)

The extraction of active compounds from natural sources has shown to be an effective approach to drug discovery. However, the isolation and identification of natural products from complex extracts can be an arduous task. A novel approach to drug discovery is presented through the use of polymer screens functionalized with an l-lysine-d-alanine-d-alanine (Kaa) peptide to create new affinity capture mesh screen materials. The Kaa sequence is a well-characterized specific binding site for antibiotics that inhibit cell wall synthesis in Gram-positive bacteria. The detailed synthesis and characterization of these novel screen materials are presented in this work. Polypropylene mesh screens were first coated with a poly(acrylic acid) film by pulsed plasma polymerization. The synthesized Kaa peptide was then covalently attached to carboxylic acid groups through a condensation reaction. An analysis of captured compounds was performed in a rapid fashion with transmission-mode desorption electrospray ionization (TM-DESI) mass spectrometry. A proof of principle was demonstrated to show the ability of the novel affinity capture materials to select for a macrocyclic antibiotic, vancomycin, over a negative control compound, spectinomycin. With further development, this method may provide a rapid screening technique for new antibacterial compounds, for example, those extracted from natural product sources having a limited supply. Here, we show that the screen can capture vancomycin preferentially over spectinomycin in a spiked extract of tea leaves.

Electrospray ionization-mass spectrometry (ESI-MS) was used to investigate stereoselective interactions between seven zwitterionic alkylsulfonate-modified cinchona alkaloid chiral selectors and biologically relevant lysine-alanine-alanine tripeptide and alanine-alanine dipeptide selectands in modified methanolic solutions. Ion intensities from full scan mass spectra were used to assess degrees of association, the ratios of which were used to calculate selectivities for different selector-selectand pairs. The results support prior work on similar systems using HPLC, in that binding is mediated in these systems primarily through the quinuclidine amine on the selector and the C-terminal carboxylate of the peptide. N(α)- and N(α), N(ɛ)-acetylated forms of the tripeptide were used to study the relative contribution to binding imparted by the presence of multiple basic amines on the tripeptide with the selectors; this was not previously investigated by HPLC. The ability of the sulfonate group on the selector to reach and preferentially interact with the N(ɛ)-amine on the side chain of lysine was revealed. Overall, in acidic methanol conditions (0.5% acetic acid), degrees of association ranged from 1.5% to 17%, and selectivities ranged from non-selective to a 5.5:1 preference for binding one peptide stereoisomer over another with a given chiral selector. In sodium acetate (100 μM)-modified methanol solutions, significant changes in degrees of association (ranging from 4% to 25%) and selectivities (ranging from non-selective to 4.2:1 preference) were observed. These mass spectrometry experiments help to clarify the chiral recognition mechanism for these selectors and suggest that retention and selectivity could be further modulated in HPLC experiments through the utilization of alkali salt-containing mobile phases., (Copyright © 2012 Elsevier B.V. All rights reserved.)

Background: Surgical Site Infections (SSI) is the third most commonly reported nosocomial infection which has an adverse impact on the hospital as well as on the patient. A continuous surveillance is called for, to keep a check on the occurrence of SSI., Objectives: to study the incidence of SSI in our hospital.to study the risk factors of SSI in our hospital.to identify the areas in our hospital, which need to be strengthened and dealt with proactive measures to curb the incidence of SSI, which is an indicator of health care system in a given set up., Methodology: We conducted a one year study of SSI in our hospital. 300 cases of Surgery and Obstetrics and Gynaecology were included in the study. A few host factors, wound factors and surgery related factors that cause SSI were studied. Swabs were collected from the infected surgical wounds and processed by the conventional microbiological methods. Antimicrobial susceptibility was done by Kirby-Bauer disc diffusion method., Results: Prolonged surgery (>2hours) and insertion of drain were found to be significantly associated with occurrence of SSI and the clean surgeries showed minimum risk of infection. Escherichia coli (31.25%) was the commonest pathogen, followed by Pseudomonas aeruginosa (25 %) and Staphylococcus aureus 22%. The incidence of SSI in our set up is 6%., Conclusions: THE OUTCOME OF THE SSI SURVEILLANCE IN OUR HOSPITAL REVEALED THAT IN ORDER TO DECREASE THE INCIDENCE OF SSI WE WOULD HAVE TO: a) decrease the duration of the surgeries performed b) focus on regular and intensive drain care c) identify poor risk patients and ensure their proper management d) conduct periodic surveillance to keep a check on SSI.