Effect of synbiotics on inflammatory markers and white blood cell count in COVID-19 patients: a randomized, double-blind, placebo-controlled clinical trial. (Special Issue: The relationship between nutrition and COVID-19.)

Purpose: Today, coronavirus disease-19 (COVID-19) treatment is an evolving process, and synbiotic administration has been suggested as a new therapeutic strategy. This study aims to investigate the effect of synbiotic supplementation in COVID-19 patients. Design/methodology/approach: In this placebo-controlled trial, 80 patients were randomized to receive oral synbiotic capsule (containing fructooligosaccharide and seven bacterial strains;Lactobacillus (L) casei, L. rhamnosus, Streptococcus thermophilus, Bifidobacterium breve, L. acidophilus, Bifidobacterium longum, L. bulgaricus, each one 109 colony-forming units) or placebo for two months. Inflammatory markers (Interleukin-6 [IL-6], C-reactive protein [CRP], erythrocyte sedimentation rate [ESR]) and white blood cell (WBC) count were evaluated at two timepoints (baseline, two months later). The measured variables were adjusted for confounders and analyzed by SPSS v21.0. Findings: All 80 enrolled patients completed the study. The study adherence was good (approximately 70%). The mean changes for IL-6 were not significant ( = -0.6 +or- 10.4 pg/mL vs = +11.2 +or- 50.3 pg/mL, p > 0.05). There were no significant improvements for CRP, ESR and WBC. Originality/value: Administration of synbiotics for two months did not improve inflammatory markers in COVID-19 patients.

Evaluation of the immunogenicity of auxotrophic Lactobacillus with CRISPR-Cas9D10A system-mediated chromosomal editing to express porcine rotavirus capsid protein VP4.

Porcine rotavirus (PoRV) is an important pathogen, leading to the occurrence of viral diarrhoea . As the infection displays obvious enterotropism, intestinal mucosal immunity is the significant line of defence against pathogen invasion. Moreover, as lactic acid bacteria (LAB) show acid resistance, bile salt resistance and immune regulation, it is of great significance to develop an oral vaccine. Most traditional plasmid delivery vectors use antibiotic genes as selective markers, easily leading to antibiotic accumulation. Therefore, to select a food-grade marker in genetically engineering food-grade microorganisms is vital. Based on the CRISPR-Cas9D10A system, we constructed a stable auxotrophic Lactobacillus paracasei HLJ-27 (Lactobacillus △Alr HLJ-27) strain. In addition, as many plasmids replicate in the host bacteria, resulting in internal gene deletions. In this study,we used a temperature-sensitive gene editing plasmidto insert the VP4 gene into the genome, yielding the insertion mutant strains VP4/△Alr HLJ-27, VP4/△Alr W56, and VP4/W56. This recombinant bacterium efficiently induced secretory immunoglobulin A (SIgA)-based mucosal and immunoglobulin G (IgG)-based humoral immune responses. These oral mucosal vaccines have the potential to act as an alternative to the application of antibiotics in the future and induce efficient immune responses against PEDV infection.

Evaluation of Lactobacillus Coryniformis K8 Consumption by Health Care Workers Exposed to COVID-19 (LactoCor2 Project): Protocol for a Randomized Controlled Trial.

BACKGROUND: Lactobacillus coryniformis K8 CECT5711 has immune-modulating properties, enhances the immune response to viral antigens leading to the production of specific antibodies, and has anti-inflammatory activity, which may help to prevent uncontrolled inflammatory processes leading to respiratory and other organ failures. OBJECTIVE: The purpose of this study is to evaluate the effect of the consumption of a probiotic strain on the incidence and severity of COVID-19 in health personnel who carry out their professional work among patients with infection or suspected infection by SARS-CoV-2. METHODS: This is a double-blind randomized clinical trial in which the experimental group will receive a capsule of L coryniformis K8 per day (3×109 colony former units/day), and the control group will receive a daily placebo capsule consisting of maltodextrin. A sample size of 314 volunteers was calculated. Volunteers must meet the following inclusion criteria: older than 20 years and active health personnel caring for patients with COVID-19, including all professionals such as medical doctors, nurses, and caretakers at the 2 referral hospitals that treat patients with COVID-19. The main outcome of the clinical trial will be the incidence of symptomatic infection by SARS-CoV-2 in personnel who care for patients with suspected or confirmed COVID-19. RESULTS: The study had to be extended to the 2 referral hospitals that treat patients with COVID-19 in the province of Granada (Andalusia, Spain); Hospital San Cecilio and Hospital Virgen de las Nieves. A total of 255 individuals met the inclusion criteria and were randomly assigned to one of the 2 groups. CONCLUSIONS: The results of this randomized controlled trial will provide valuable information regarding the administration of L coryniformis K8 against COVID-19, including whether there are fewer infectious processes due to this virus or, in case of occurrence, whether the disease is milder in participants taking the probiotic strain. TRIAL REGISTRATION: ClinicalTrials.gov NCT04366180; http://www.clinicaltrials.gov/ct2/show/NCT04366180. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): RR1-10.2196/37857.

A Case of Lactobacillus casei Endocarditis Associated With Probiotic Intake in an Immunocompromised Patient.

Probiotics are microorganisms, typically bacteria, similar to beneficial microbiota found in the human gut, usually consumed as dietary supplements or fermented foods. Although probiotics are generally safe, several cases of bacteremia, sepsis, and endocarditis associated with probiotics have been reported. Here we report a rare case of Lactobacillus casei endocarditis in a 71-year-old female, immunocompromised due to chronic steroid intake, who presented with a productive cough and low-grade fever. Blood cultures grew L. casei resistant to vancomycin and meropenem. Transesophageal echocardiography showed mitral and aortic vegetations; valve replacement was done after successfully removing vegetations. She was treated with a six-week course of daptomycin and recovered.

Efficiency of application of sorbed probiotics in the complex therapy of pneumonia caused by SARS-CoV-2. Quality of life in the short term COVID-19

Aim. To determine the clinical efficacy and safety of the immobilized (sorbed) probiotics Bifidobacterium bifidum 1 (5x108 CFU) and B. bifidum 1 (5x107 CFU) in combination with Lactobacillus plantarum 8P-A3 (5x107 CFU) in the complex therapy of pneumonia caused by SARS-CoV-2 in adult patients without severe risk factors and their impact on health-related quality of life (QoL). Material and methods. An open, randomized prospective study included 100 patients (45 males, 55 females), aged from18 to 60 years without risk factors for severe COVID-19, with pneumonia confirmed by computed tomography and an area of lung lesion no more than 75% (moderate forms). SARS-CoV-2 RNA in nasal and oropharyngeal swabs (RT-PCR) was detected in 72% of the participants, in the rest it was highiy probable in terms of the aggregate parameters. The publication presents the results of self-assessment (94 respondents) of working capacity limitations, shortness of breath, intestinal disorders since the end of the probiotic regimen (PR: hospitalization period - B. bifidum 1, 3 capsules 2 times a day for 10 days, then after hospitalization - B. bifidum 1 in combination with L. plantarum 8P-A3 2 powders 3 times a day for 14 days) and QoL (Short Form Medical Outcomes Study: SF-36) 1 month after hospitalization. Results. At the end of PR, the ability to engage in daily activities was higher by 23.1% [95% confidence interval 5.3-37.3, OR 0.08 (0.08-0.77)]. Difficulty of breathing during exercise was less common by 29.7% [15.1-44.5%], OR 0.09 [0.02-0.40], hard stools and no bowel movements were recorded less often by 21.3% [8.5-34, 1] for 1-3 days. One month after hospitalization, the QoL of the patients receiving standard treatment was significantly reduced relative to population indicators in Russia. It was more significantly due to the psychological component of health [total measurement 38.1 (36.2-40.0)] and less significantly due to the physical component [49.5 (48.3-50.8)]. The main reasons limiting daily activities [Role Emotional (RE): 39.4 (37.4-41.4)] were decreased vitality [VT: 40.2 (38.9-041.5)], emotional depression [Mental Health (MH): 41.2 (39.4-43.0)], deficit of social contacts [Social Functioning (SF): 45.1 (43.7-46.6)]. The patients who received PR had a higher ability to carry out daily activities [RE: 57.7 (55.6-59.7)], the severity of psychological problems associated with fatigue, anxiety and depression was lower [MH: 59.8 (58.7-60.9), p<0,001]. The effect of the PR on negative perceptions of social isolation was comparatively less [SF: 53.9 (52.2-55.4)]. The QoL of the patients who additionally suffered from diarrhea in the acute period of SARS-CoV-2 pneumonia was worse in comparison with the patients without diarrhea (due to pain and inability to endure physical activity). The effects of immobilized (sorbed) probiotics to the QoL of the patients with diarrhea during the acute period of COVID-19 were most significant. Conclusion. PR had a significant positive effect on the QoL within a month after hospitalization, increasing working capacity and improving mental health, reducing the severity of psychological problems and fatigue. Additional researches are needed on the possible relationship of organic and functional gastrointestinal diseases with the progression of diarrhea in patients infected with SARS-CoV-2. No side effects of the sorbed probiotics regimen have been identified.Copyright © Eco-Vector, 2022.

Can the Therapeutic Spectrum of Probiotics be Extended: Exploring Potential of Gut Microbiome.

Natural therapeutic microorganisms provide a potent alternative healthcare treatment nowadays, with the potential to prevent several human diseases. These health-boosting living organisms, probiotics mostly belong to Gram-positive bacteria such as Lactobacillus, Bifidobacterium, Streptococcus, Saccharomyces, Bacillus and Enterococcus. Initiated almost a century ago, the probiotic application has come a long way. The present review is focused on the potential therapeutic role of probiotics in ameliorating multiple infections, such as upper respiratory tract infections and viral respiratory infections, including Covid-19; liver diseases and hepatic encephalopathy; neurological and psychiatric disorders; autoimmune diseases, particularly rheumatoid arthritis, systemic lupus erythematosus and multiple sclerosis. Apart from these, the therapeutic exacerbations of probiotics in urinary tract infections have been extremely promising, and several approaches are reviewed and presented here. We also present upcoming and new thrust areas where probiotic therapeutic interventions are showing promising results, like faecal microbial transplant and vaginal microbial transplant.

Impact of Gut Microbiota on Immunogenicity to Covid-19 Vaccines in Plwh

Background: Immune responses to SARS-CoV-2 vaccines in people living with HIV (PLWH) have been the focus of several recent studies. As the gut microbiome can influence vaccine immunogenicity, in this study we are the first to investigate whether the baseline gut microbiota can predict immune responses to the BNT162b2 SARS-CoV-2 vaccine in people living with HIV (PLWH) and healthy controls (HC). Method(s): Fecal samples were collected from PLWH (n=68) and HC (n=75) at baseline, prior to the first vaccine dose, to extract DNA for 16S rRNA sequencing. The individuals were part of the COVAXID Clinical trial, where humoral and cellular responses to SARS-CoV-2 vaccine were evaluated on day 35 after the first dose. Comprehensive bioinformatic tools were used for bacterial identification to further reveal the associations between gut microbiota and SARS-CoV-2 antibody, spike CD4+ T cell responses, and clinical parameters such as age, gender, CD4/CD8 ratio, and length of antiretroviral (ART) treatment. Result(s): At day 35 post vaccination, HC showed significantly higher spike IgG titers than PLWH (p=0.0001). Interestingly, both phylogenetic and alpha-diversity were negatively correlated with antibody titers, in the whole cohort and within groups. Similarly, individuals with low alpha-diversity had higher levels of spike specific CD4+T-cell responses. Agathobacter, Lactobacillus, Bacteroides, and Lachnospira were positively correlated with both antibody levels and spike-specific CD4+ T-cell responses while Methanobrevibacter, Marvinbryantia, Cloacibacillus, and Succinivibrio have a negative one. Within the PLWH group, the gut microbiota taxa associated with CD4+ counts, such as Lachnospira (p=0.002), Oscillibacter (p=0.019) and Flavonifractor (p=0.017), were found to be positively correlated with spike IgG levels. Additionally, the length of ART treatment and CD4/CD8 ratio displayed a positive association with bacterial diversity. Notably, different microbiome profiles and immune status in PLWH, affect their immune responses to vaccination. Conclusion(s): Our results show potential associations between gut microbiota diversity and spike IgG responses after COVID-19 vaccination. These findings were consistent in the whole cohort, albeit group differences between the microbiome compositions in PLWH and HC were observed. Based on our findings, we propose that microbiome modulation could optimize immunogenicity to SARS-Cov-2 vaccines.

Current status of probiotic and related health benefits

This review is aimed to explore the health beneficial effects of probiotics which are live microorganisms that provide a positive health influence on humans when taken in sufficient quantity. Lactic acid bacteria, bifidobacteria, and yeast are frequently used as probiotics. These health-beneficial bacteria could compete with pathogens and modulate the gut microbiota, and exhibit immunomodulatory, anti-obesity, anti-diabetic, and anti-cancer activities which are discussed in this review. Moreover, recent studies showed that probiotics could neutralize COVID-19 infections. Hence, probiotics have become an alternative to several drugs including antibiotics. In addition, probiotic efficacy also depends on the delivery system as the delivery agents help the bacteria to survive in the harsh environment of the human gut. Considering these health benefits of probiotics, now it has been applied to different food materials which are designated as functional food. This review explored a portrait of the beneficial effects of probiotics on human health.Copyright © 2022 The Author(s)

Psychobiotics: a new way in psychopharmacology, or How do bacteria manage our brain?.

Psychobiotics are a special class of probiotics that have a beneficial effect on human mental health. During the last decade, convincing evidence has emerged that the gut microbiome influences mental health, cognitive abilities (learning and memory), and behavioral processes through neurological, metabolic, hormonal, and immunological signaling pathways. This review provides available information on the mechanisms of regulation of neuroimmune axes by the microbiota, describes the schemes of interaction of the microbiota with the intestinal nervous system and the brain-gut axis, the effect on behavior, cognitive functions and emotions, and discusses the evidence base and current views on the use of psychobiotics as a safe and effective therapeutic alternative to classic psychotropic drugs in depressive and anxiety disorders, stress, autism spectrum disorders, Alzheimer's disease and other conditions.Copyright © 2022, Interregional Association for Clinical Microbiology and Antimicrobial Chemotherapy. All rights reserved.

Peculiarities of Periodontal Pocket Microbiome in Patients with Generalized Periodontitis in the Post-Covid Period

The oral cavity, like the lungs, is often referred to as the <<ecological niche of commensal, symbiotic, and pathogenic or-ganisms,>> and the emigration and elimination of microbes between them are constant, ensuring a healthy distribution of saprophytic microorganisms that maintains organ, tissue, and immune homeostasis. The prolonged hospital stays due to COVID-19 complications, cross-infection, oxygenation therapy through the mask or incubation, and long-term intravenous infusions limit the patient's ability to care about the oral cavity, regularly clean teeth, floss interdental, etc., which creates extremely favorable conditions for colonization by aerobic and anaerobic pathogens of the oral cavity and periodontal pockets and leads to the rapid progression of chronic generalized periodontitis in this category of patients in the future. The goal of the study was to assess the state of the microbiome of the periodontal pockets of dental patients in the post-covid period. Methods. The object of the study was 140 patients with generalized periodontitis of the I and II stages of development in the chronic course (GP), among which 80 patients had coronavirus disease in the closest past. The patients were randomized by age, sex, and stage of GP development. The diagnosis of periodontal disease was established according to the classification by Danilevskyi. The bacteriological material for aerobic and facultative anaerobic microflora and yeast-like fungi was collected from periodontal pockets with a calibrated bacteriological loop and immediately seeded on blood agar. Results. Significant qualitative and quantitative changes in the nature of the oral microbiocenosis were observed in patients with GP after the recent coronavirus disease, compared with similar patients who did not suffer from COVID-19. We have noticed almost complete disappearance of bacteria that belong to the transient representatives of the oral microflora such as Neisseria, corynebacteria (diphtheria), micrococci, and lac-tobacilli. The main resident representatives of the oral microflora, i.e., alpha-hemolytic Streptococci of the mitis group, were found in all healthy individuals and patients of groups A and C, but in 30.0 +/- 4.58% of patients in group B, alpha-hemolytic streptococci in the contents of periodontal pockets are present in quantities not available for detection by the applied method (<2.7 lg CCU/mL). In terms of species, Streptococcus oralis and Streptococcus salivarius are more characteris-tic in gingival crevicular fluid in healthy individuals (93.8% of selected strains). In 68.4 +/- 3.32% of patients in group A, 64.0 +/- 3.43% of patients in group B, and 67.5 +/- 3.76% of patients in group C, the dominant species were Streptococcus gordonii and Streptococcus sanguinis (p<0.01), which increased pathogenic potential as they produce streptolysin-O, inhibit complement activation, bind to fibronectine, actively form biofilms on the surface of tooth enamel and gum epithelial surface, and can act as an initiator of adhesion of periodontal pathogens. The other representatives of the resident microflora of the oral cavity - Stomatococcus mucilaginosus and Veillonella parvula for the patients of group C are also found in periodontal pockets with a significantly lower index of persistence and minimal population level. In the post-covid period, both the population level and the frequency of colonization of periodontal pockets by Staphylo-cocci and beta-hemolytic Streptococci decreases rapidly. For these patient groups, unlike for those that did not suffer from COVID-19, we did not find any case of colonization with Staphylococcus aureus, as well as beta-hemolytic Streptococci and Epidermal staphylococcus were also absent. The most characteristic in the post-covid period is a decrease in the proportion of alpha-hemolytic Streptococci, an increase in the proportion of yeast-like fungi of Candida species, as well as the appearance of a significant number of gram-negative rod-shaped bacteria (Enterobacteria and Pseudomonads). In periodontal patien s, the microbial count is approximately 2 orders of magnitude lower than in those with GP who did not suffer from COVID-19 (p<0.05). Conclusions. The overpassed coronavirus disease due to intensive antibiotic therapy leads to a marked decrease in the number of viable saprophytic microorganisms in the periodontal pockets of patients with GP. In the post-covid period for the patients with GP, there is a decrease in the level of colonization of periodontal pockets by species of resident oral microflora - alpha-hemolytic Streptococci, reduction of resident micro-organism's species, and almost complete disappearance of transient microflora. On the other hand, the frequency of colonization of periodontal pockets by fungi species, enterobacteria, and pseudomonads significantly increases. There are more expressed disorders in the periodontal pocket's microbiome for the patients with a severe and complicated course of coronavirus disease, such as post-covid pulmonary fibrosis, which requires reconsideration of approaches to therapeutic and pharmacological treatment in this category of patients.Copyright © 2022, Zabolotny Institute of Microbiology and Virology, NAS of Ukraine. All rights reserved.

Landscape Analysis of Quercetin: A Potential Candidate Against SARS-CoV-2

Fruit, vegetables, and green tea contain quercetin (a flavonoid). Some of the diet's most signifi-cant sources of quercetin are apples, onions, tomatoes, broccoli, and green tea. Antioxidant, anticancer, anti-inflammatory, antimicrobial, antibacterial, and anti-viral effects have been studied of quercetin. The severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) virus, ribonucleic acid (RNA) polymer-ase, and other essential viral life-cycle enzymes are all prevented from entering the body by quercetin. Despite extensive in vitro and in vivo investigations on the immune-modulating effects of quercetin and vitamin C treatment. 3-methyl-quercetin has been shown to bind to essential proteins necessary to convert minus-strand RNA into positive-strand RNAs, preventing the replication of viral RNA in the cytoplasm. Quercetin has been identified as a potential SARS-CoV-2 3C-like protease (3CLpro) suppressor in recent molecular docking studies and in silico assessment of herbal medicines. It has been demonstrated that quercetin increases the expression of heme oxygenase-1 through the nuclear factor erythroid-related factor 2 (Nrf2) signal network. Inhibition of heme oxygenase-1 may increase bilirubin synthesis, an endoge-nous antioxidant that defends cells. When human gingival fibroblast (HGF) cells were exposed to lipo-polysaccharide (LPS), inflammatory cytokine production was inhibited. The magnesium (Mg+2) cation complexation improves quercetin free radical scavenging capacity, preventing oxidant loss and cell death. The main objective of this paper is to provide an overview of the pharmacological effects of quercetin, its protective role against SARS-CoV-2 infection, and any potential molecular processes.Copyright © 2022 Bentham Science Publishers.

Heat-killed Lactobacillus murinus confers neuroprotection against dopamine neuronal loss by targeting NLRP3 inflammasome.

The intestinal flora has become very active in studies related to Parkinson's disease (PD) in recent years. The microbe-gut-brain axis is closely related to the maintenance of brain homeostasis as well as PD pathogenesis. Alterations in gut bacteria can contribute to neuroinflammation and dopamine (DA) neurodegeneration. Lactobacillus murinus, a gram-positive bacterium, is a commensal gut bacteria present in the mammalian gut and considered as a potential probiotic due to its beneficial effects, including anti-inflammatory and antibacterial actions. In this study, the effects of live L. murinus and heat-killed L. murinus on DA neuronal damage in rats and the underlying mechanisms were investigated. Data showed that heat-killed L. murinus ameliorated 6-hydroxydopamine-induced motor dysfunctions and loss of substantia nigra DA neurons, while no protection was shown in live L. murinus treatment. At the same time, heat-killed L. murinus reduced the activation of NLRP3 inflammasome in microglia and the secretion of pro-inflammatory factors, thus inhibiting the development of neuroinflammation. Furthermore, heat-killed L. murinus failed to display its original neuroprotective properties in NLRP3 inflammasome knockout mice. Together, heat-killed L. murinus conferred neuroprotection against DA neuronal loss via the inhibition of microglial NLRP3 inflammasome activation. These findings provide a promising potential for future applications of L. murinus, and also beneficial strategy for PD treatment.

Endotipsitis in an Immunocompetent Patient With Lactobacillus Bacteremia.

Transjugular intrahepatic portosystemic shunt (TIPS) is a procedure commonly performed to decompress portal venous pressure since the early 1990s. Endotipsitis, which refers to persistent bacteremia caused by endovascular infection of the TIPS stent, is a rare but serious complication of this procedure. Very few cases of endotipsitis have been reported worldwide. We report the case of an immunocompetent patient diagnosed with endotipsitis, an atypical risk factor for Lactobacillus infection. This case report adds to the literature on underreported complications of TIPS, highlighting an urgent need for introducing clinical practice guidelines regarding the definition, diagnosis, and treatment of endotipsitis.

Efficiency of application of sorbed probiotics in the complex therapy of pneumonia caused by SARS-CoV-2. Quality of life in the short term COVID-19

Aim. To determine the clinical efficacy and safety of the immobilized (sorbed) probiotics Bifidobacterium bifidum 1 (5×108 CFU) and B. bifidum 1 (5×107 CFU) in combination with Lactobacillus plantarum 8P-А3 (5×107 CFU) in the complex therapy of pneumonia caused by SARS-CoV-2 in adult patients without severe risk factors and their impact on health-related quality of life (QoL). Material and methods. An open, randomized prospective study included 100 patients (45 males, 55 females), aged from18 to 60 years without risk factors for severe COVID-19, with pneumonia confirmed by computed tomography and an area of lung lesion no more than 75% (moderate forms). SARS-CoV-2 RNA in nasal and oropharyngeal swabs (RT-PCR) was detected in 72% of the participants, in the rest it was highiy probable in terms of the aggregate parameters. The publication presents the results of self-assessment (94 respondents) of working capacity limitations, shortness of breath, intestinal disorders since the end of the probiotic regimen (PR: hospitalization period – B. bifidum 1, 3 capsules 2 times a day for 10 days, then after hospitalization – B. bifidum 1 in combination with L. plantarum 8P-А3 2 powders 3 times a day for 14 days) and QoL (Short Form Medical Outcomes Study: SF-36) 1 month after hospitalization. Results. At the end of PR, the ability to engage in daily activities was higher by 23.1% [95% confidence interval 5.3–37.3, OR 0.08 (0.08–0.77)]. Difficulty of breathing during exercise was less common by 29.7% [15.1–44.5%], OR 0.09 [0.02–0.40], hard stools and no bowel movements were recorded less often by 21.3% [8.5–34, 1] for 1–3 days. One month after hospitalization, the QoL of the patients receiving standard treatment was significantly reduced relative to population indicators in Russia. It was more significantly due to the psychological component of health [total measurement 38.1 (36.2–40.0)] and less significantly due to the physical component [49.5 (48.3–50.8)]. The main reasons limiting daily activities [Role Emotional (RE): 39.4 (37.4–41.4)] were decreased vitality [VT: 40.2 (38.9–041.5)], emotional depression [Mental Health (MH): 41.2 (39.4–43.0)], deficit of social contacts [Social Functioning (SF): 45.1 (43.7–46.6)]. The patients who received PR had a higher ability to carry out daily activities [RE: 57.7 (55.6–59.7)], the severity of psychological problems associated with fatigue, anxiety and depression was lower [MH: 59.8 (58.7–60.9), р<0,001]. The effect of the PR on negative perceptions of social isolation was comparatively less [SF: 53.9 (52.2–55.4)]. The QoL of the patients who additionally suffered from diarrhea in the acute period of SARS-CoV-2 pneumonia was worse in comparison with the patients without diarrhea (due to pain and inability to endure physical activity). The effects of immobilized (sorbed) probiotics to the QoL of the patients with diarrhea during the acute period of COVID-19 were most significant. Conclusion. PR had a significant positive effect on the QoL within a month after hospitalization, increasing working capacity and improving mental health, reducing the severity of psychological problems and fatigue. Additional researches are needed on the possible relationship of organic and functional gastrointestinal diseases with the progression of diarrhea in patients infected with SARS-CoV-2. No side effects of the sorbed probiotics regimen have been identified. © Eco-Vector, 2022.

Protein hydrolysates of a probiotic strain of Lactobacillus plantarum as new promising sources of inhibitors for diabetes regulatory enzymes

Diabetes is a chronic metabolic disorder characterized by persistent hyperglycaemia. It has been classified as one of the main pathologies that promotes the most severe and fatal forms of COVID-19. Although there are nowadays synthetic molecules for the regulation of this disease, their disastrous side effects still open up prospects for the search of new and healthy molecules of therapeutic interest. This study aimed at evaluating the inhibitory effect of peptides extracts produced during the cultivation of a Lactobacillus plantarum strain with probiotic properties. The peptides extracts were obtained by thermal hydrolysis of protein extracts at 70 degrees C or 80 degrees C for 10, 20 and 30 min. The potential hypoglycaemic activity was examined by testing their inhibitory effect on amylolytic enzymes. Our results showed that the studied proteins hydrolysates, when used at 0.024 mg (biomass) or 0.156 mg (growth broth), were capable of total inhibition of amylolytic enzymes activity. The biomass peptides showed higher inhibition rate compared to 95% obtained with 0.050 mg of acarbose, a potent and widely used anti-diabetic inhibitory. This study clearly shows that the investigated protein hydrolysates contain interesting inhibitory peptides that deserve further investigations for their real use as bioactive inhibitors of diabetes regulating enzymes.

The Probiotic Attributes and Anti-pseudorabies Virus Evaluation of Lactobacillus Isolates.

The emergence of pseudorabies virus (PRV) variants brings serious harm to the swine industry, and its effective treatments are limited at present. As one of the probiotics, the Lactobacillus species have beneficial characteristics of regulating the balance of intestinal flora, inhibiting the growth of pathogenic bacteria and viruses' proliferation, and improving self-immunity. In this study, Lactobacillus plantarum HN-11 and Lactobacillus casei HN-12 were selected and identified through morphology observation, Gram stain microscopy, 16S rRNA sequencing analysis, and specific amplification of the recA gene and pheS gene. All tested isolates exhibited rapid adaptation to the different conditions, excellent acid, and bile tolerance, and sensitivity to Salmonella, Staphylococcus aureus, and Escherichia coli. The antibiotic susceptibility assay displayed the isolates sensitive to most antibiotics and resistant to Lincomycin and Norfloxacin. Moreover, the supernatants of HN-11 and HN-12 inhibited PRV proliferation in ST cells. The results of animal experiments showed that supplementing the challenged mice with the supernatants of Lactobacillus isolates in advance delayed the course of the disease. PRV was detected in the heart, liver, spleen, lung, kidney, and brain tissues of dead mice in the test groups, and its copies in the lungs were significantly decreased compared with the control mice (P < 0.05). These findings proved the advantages of L. plantarum and L. casei as potential probiotic cultures, which could provide a basis for its application in microecological preparations and functional formulations.

The Inhibition of SARS-CoV-2 and the Modulation of Inflammatory Responses by the Extract of Lactobacillus sakei Probio65.

In the three years since the first outbreak of COVID-19 in 2019, the SARS-CoV-2 virus has continued to be prevalent in our community. It is believed that the virus will remain present, and be transmitted at a predictable rate, turning endemic. A major challenge that leads to this is the constant yet rapid mutation of the virus, which has rendered vaccination and current treatments less effective. In this study, the Lactobacillus sakei Probio65 extract (P65-CFS) was tested for its safety and efficacy in inhibiting SARS-CoV-2 replication. Viral load quantification by RT-PCR showed that the P65-CFS inhibited SARS-CoV-2 replication in human embryonic kidney (HEK) 293 cells in a dose-dependent manner, with 150 mg/mL being the most effective concentration (60.16% replication inhibition) (p < 0.05). No cytotoxicity was inflicted on the HEK 293 cells, human corneal epithelial (HCE) cells, or human cervical (HeLa) cells, as confirmed by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay. The P65-CFS (150 mg/mL) also reduced 83.40% of reactive oxidizing species (ROS) and extracellular signal-regulated kinases (ERK) phosphorylation in virus-infected cells, both of which function as important biomarkers for the pathogenesis of SARS-CoV-2. Furthermore, inflammatory markers, including interferon-α (IFN-α), IFN-ß, and interleukin-6 (IL-6), were all downregulated by P65-CFS in virus-infected cells as compared to the untreated control (p < 0.05). It was conclusively found that L. sakei Probio65 showed notable therapeutic efficacy in vitro by controlling not only viral multiplication but also pathogenicity; this finding suggests its potential to prevent severe COVID-19 and shorten the duration of infectiousness, thus proving useful as an adjuvant along with the currently available treatments.

Modulation of Alveolar Macrophages by Postimmunobiotics: Impact on TLR3-Mediated Antiviral Respiratory Immunity.

Beneficial microbes with immunomodulatory capacities (immunobiotics) and their non-viable forms (postimmunobiotics) could be effectively utilized in formulations towards the prevention of respiratory viral infections. In this study, novel immunobiotic strains with the ability to increase antiviral immunity in porcine alveolar macrophages were selected from a library of Lactobacillus gasseri. Postimmunobiotics derived from the most remarkable strains were also evaluated in their capacity to modulate the immune response triggered by Toll-like receptor 3 (TLR3) in alveolar macrophages and to differentially regulate TLR3-mediated antiviral respiratory immunity in infant mice. We provide evidence that porcine alveolar macrophages (3D4/31 cells) are a useful in vitro tool for the screening of new antiviral immunobiotics and postimmunobiotics by assessing their ability to modulate the expression IFN-ß, IFN-λ1, RNAseL, Mx2, and IL-6, which can be used as prospective biomarkers. We also demonstrate that the postimmunobiotics derived from the Lactobacillus gasseri TMT36, TMT39 and TMT40 (HK36, HK39 or HK40) strains modulate the innate antiviral immune response of alveolar macrophages and reduce lung inflammatory damage triggered by TLR3 activation in vivo. Although our findings should be deepened and expanded, the results of the present work provide a scientific rationale for the use of nasally administered HK36, HK39 or HK40 to beneficially modulate TLR3-triggerd respiratory innate immune response.

Delivery of antigen to porcine dendritic cells by fusing antigen with porcine dendritic cells targeting peptide.

Dendritic cells (DCs) are professional antigen-presenting cells that can recognize, capture, and process antigens. Fusing molecules targeting DCs with antigens can effectively improve the efficiency with which antigens are recognized and captured by DCs. This targeting strategy can be used for vaccine development to effectively improve the efficiency of antigen recognition and capture by DCs. The targeting sequence of porcine cytotoxic T-lymphocyte associated protein 4 (CTLA4), which binds porcine DCs, was identified in this study. Recombinant Lactobacillus reuteri (L. reuteri) expressing CTLA4-6aa (LYPPPY) and CTLA4-87aa fused to the porcine epidemic diarrhea virus (PEDV) protective antigen core neutralizing epitope (COE) were used to evaluate the ability of the two targeting motifs to bind the B7 molecule on DCs. Our results demonstrate that CTLA4-6aa could bind porcine DCs, and recombinant Lactobacillus expressing the CTLA4-6aa captured by porcine DCs was more efficient than those expressing CTLA4-87aa. In addition, the expression of DC markers, toll-like receptors, and cytokines was significantly higher in the 6aa-COE/L. reuteri-stimulated porcine DCs compared to DCs treated with 87aa-COE/L. reuteri (p<0.01) and recombinant Lactobacillus expressing CTLA4-6aa enhanced the ability of porcine DCs to activate T-cell proliferation. Our analysis of the protein structure revealed that CTLA4-87aa contains intramolecular hydrogen bonds, which may have weakened the intermolecular force between the residues on porcine CTLA4 and that on B7. In conclusion, recombinant Lactobacillus expressing CTLA4-6aa were more efficiently captured by porcine DCs and had a stronger ability to promote DC maturation and enhance T-cell proliferation. The LYPPPY motif is the optimal sequence for binding to porcine DCs. Piglets immunized with recombinant Lactobacillus showed that recombinant Lactobacillus expressing CTLA4-6aa induced significant levels of anti-PEDV-specific IgG and IgA antibody responses. Our study may promote research on DC-targeting strategies to enhance the effectiveness of porcine vaccines.

Chicken intestinal microbiota modulation of resistance to nephropathogenic infectious bronchitis virus infection through IFN-I.

BACKGROUND: Mammalian intestinal microbiomes are necessary for antagonizing systemic viral infections. However, very few studies have identified whether poultry commensal bacteria play a crucial role in protecting against systemic viral infections. Nephropathogenic infectious bronchitis virus (IBV) is a pathogenic coronavirus that causes high morbidity and multiorgan infection tropism in chickens. RESULTS: In this study, we used broad-spectrum oral antibiotics (ABX) to treat specific pathogen free (SPF) chickens to deplete the microbiota before infection with nephropathogenic IBV to analyze the impact of microbiota on IBV infections in vivo. Depletion of the SPF chicken microbiota increases pathogenicity and viral burden following IBV infection. The gnotobiotic chicken infection model further demonstrated that intestinal microbes are resistant to nephropathogenic IBV infection. In addition, ABX-treated chickens showed a severe reduction in macrophage activation, impaired type I IFN production, and IFN-stimulated gene expression in peripheral blood mononuclear cells and the spleen. Lactobacillus isolated from SPF chickens could restore microbiota-depleted chicken macrophage activation and the IFNAR-dependent type I IFN response to limit IBV infection. Furthermore, exopolysaccharide metabolites of Lactobacillus spp. could induce IFN-ß. CONCLUSIONS: This study revealed the resistance mechanism of SPF chicken intestinal microbiota to nephropathogenic IBV infection, providing new ideas for preventing and controlling nephropathogenic IBV. Video abstract.