The varying effects of antibiotics on gut microbiota

Antibiotic Use and Risk of Microscopic Colitis in Older Adults: A Nationwide Self-Controlled Case Series Study

BACKGROUND

Several drugs have been linked to the risk of microscopic colitis (MC), a condition characterised by watery, non-bloody diarrhoea. Antibiotics can induce similar symptoms, but their connection to MC remains unclear.

AIM

To investigate the antibiotic-related risks of MC in adults aged 65 years and older.

METHODS

This was a nationwide, self-controlled case series study including adults aged ≥ 65 years with a new prescription for antibiotics and biopsy-confirmed, incident MC (Sweden, 2007-17). We identified cases from the nationwide histopathology cohort ESPRESSO individually linked to several registers. Using conditional Poisson regression, we estimated incidence rate ratios (IRR) for four risk periods: on treatment, and 1-14, 15-91, and 92-365 days post-treatment, compared with the non-treatment periods in the same individual. We also conducted a negative control outcome analysis to assess whether the association was specific to MC or due to diagnostic workup. E-values were used to assess robustness to unmeasured confounding.

RESULTS

We identified 2393 persons with incident biopsy-confirmed MC (median age at diagnosis 74; 67% women). Compared with the non-treatment periods, the risk of MC in the age-adjusted analysis increased with antibiotic treatment (IRR: 1.44 [95% CI: 1.13-1.84], E-value: 2.24), 1-14 days (IRR: 1.12 [0.83-1.49]), 15-91 days (1.12 [0.97-1.31]) and 92-365 days post-treatment (1.19 [1.07-1.32]). The negative control outcome analysis showed similar risks of biopsy-confirmed normal mucosa after antibiotic use.

CONCLUSION

The observed association between antibiotic use and MC may result from detection bias rather than a causal relationship.

Chitosan from sea urchin (Diadema setosum) spines for orthodontic miniscrews: Antibacterial effects against key oral pathogens

Objective

Peri-implantitis, exacerbated microbial growth characterized by progressive bone loss and soft-tissue inflammation, significantly contributes to miniscrew failure during orthodontic treatment. Using a natural antibacterial coating presents an innovative approach to combat bacterial colonization. Sea urchin (Diadema setosum) spines containing chitosan (CS) exhibit notable antibacterial properties and biocompatibility effects. This study investigates the antimicrobial potential of CS from sea urchin spines applied onto the surfaces of orthodontic miniscrews, aiming to mitigate the impact of peri-implantitis.

Materials and methods

The surface functional groups, phase composition, and crystal structure of CS were investigated using traditional examination methods alongside energy-dispersive X-ray analysis. The antibacterial activity of CS was evaluated against three bacteria by the disk diffusion method, minimum bacterial concentration (MBC), and minimum inhibitory concentration (MIC). Stainless steel miniscrews were coated with CS, and the surface was characterized by scanning electron microscopy (SEM).

Results and discussion

Sea urchin-derived chitosan demonstrated significant antibacterial effects against key oral pathogens associated with peri-implantitis, with minimum inhibitory concentrations (MICs) of 16 ppm against Fusobacterium nucleatum and 32 ppm for both Aggregatibacter actinomycetemcomitans and Porphyromonas gingivalis. The minimum bactericidal concentrations (MBCs) were 4 ppm for A. actinomycetemcomitans and 16 ppm for both F. nucleatum and P. gingivalis, indicating its strong bactericidal potential. Scanning electron microscopy (SEM) revealed that sea urchin chitosan effectively adhered to the surface of orthodontic miniscrews, showcasing its potential as a functional antimicrobial coating. These results emphasize the capability of sea urchin chitosan to target key oral pathogens, offering a promising approach to enhance microbial resistance and improve outcomes in orthodontic treatments.

Epidemiology and Microbiology of Healthcare-Associated Infections in Neurosurgery Department: A Cross-Sectional Study

Objective: Hospital-acquired infections (HAIs) present a significant challenge in neurosurgical settings. This study aimed to assess the prevalence, risk factors, and clinical impact of HAIs in a neurosurgery department. Methods: A retrospective cross-sectional study was conducted on 5474 patients hospitalized in a neurosurgery department (2019-2023). HAIs were diagnosed in 93 patients (2.7%), accounting for 147 infections. The final cohort included 273 patients: 93 with HAIs and 181 matched controls (age, sex, mortality). Demographic, clinical, and microbiological data were analyzed. Nutritional status was assessed using the Nutritional Risk Screening (NRS, 2002) and consciousness was assessed using the Glasgow Coma Scale (GCS). Infections were classified according to Centers for Disease Control and Prevention (CDC) criteria. Results: The most frequent HAIs were pneumonia (PN, 18.3%), bloodstream infections (BSI, 16.2%), and surgical site infections (SSI, 16.3%). Malnutrition (NRS ≥3) was significantly more common in infected patients (65.6% vs. 11%, p < .001). Patients with GCS ≤8 had higher rates of PN (44.7%) and urinary tract infections (UTI, 32.5%) (p = .004), while GCS 13-15 was linked to SSI (91.7%). HAIs occurred more frequently after emergency procedures (57.8% vs. 30%, p < .0001). Hospital stay was significantly longer in infected patients (40 vs. 5.4 days, p = .001). Klebsiella pneumoniae (15.1%) and Staphylococcus aureus (11.5%) were the most common. Age and sex were not significant risk factors. Conclusion: HAIs in neurosurgical patients are associated with malnutrition and procedural urgency. Targeted infection control, early nutrition support, and antimicrobial stewardship are essential to improving outcomes.

Abnormal microbiota due to prenatal antibiotic as a possible risk factor for Attention-Deficit / Hyperactivity Disorder (ADHD)

One of the major issues modern medicine faces is the increasing use of antibiotics in reaction to the increased incidence of infectious agents. The current trend of antibiotic overuse contributes to microbial dysbiosis. Recent studies have hypothesized that antibiotic exposure during pregnancy, which alters the composition of the microbiome, might increase the likelihood of attention deficit hyperactivity disorder (ADHD). In addition to the ongoing discussion about the potential links between antibiotic usage, microbiome dysbiosis, and ADHD, there is a rising interest in integrating AI and ML into healthcare practices. Diagnosis, treatment plans, and prognoses are all enhanced by these technological advancements. Remote monitors or telemedicine monitoring are among the management techniques described in this chapter for effectively managing illnesses. Also discussed are ways to halt the progression of diseases by preventative measures that use biosensor technology and dietary approaches. Personalized treatment programs, disease progression stages, and prognosis evaluations are all made possible with the use of artificial intelligence and machine learning. By using these technologies to provide individualized therapy, healthcare practitioners may get a better understanding of ADHD and perhaps improve patient outcomes.

Key Insights into Gut Alterations in Metabolic Syndrome

Over time, extensive research has underscored the pivotal role of gut microbiota in the onset and progression of various diseases, with a particular focus on fecal microbiota transplantation (FMT) as a potential therapeutic approach. The practice of transferring fecal matter from a healthy donor to a patient provides valuable insights into how alterations in gut microbiota can impact disease development and how rectifying dysbiosis may offer therapeutic benefits. Re-establishing a balanced symbiotic relationship in the gastrointestinal tract has shown positive results in managing both intestinal and systemic conditions. Currently, one of the most pressing global health issues is metabolic syndrome-a cluster of conditions that includes insulin resistance, lipid imbalances, central obesity and hypertension. In this context, FMT has emerged as a promising strategy for addressing key components of metabolic syndrome, such as improving insulin sensitivity, body weight and lipid profiles. However, further well-structured studies are needed to refine treatment protocols and establish the long-term safety and efficacy of this intervention.

TASTY trial: protocol for a study on the triad of nutrition, intestinal microbiota and rheumatoid arthritis

BACKGROUND

The gut microbiota has been implicated in the onset and progression of Rheumatoid Arthritis (RA). It has been proposed that gut dysbiosis impairs gut barrier function, leading to alterations in mucosal integrity and immunity. This disruption allows bacterial translocation, contributing to the perpetuation of the inflammatory process. Since diet is recognised as a key environmental factor influencing the gut microbiota, nutritional interventions targeting RA activity are currently being explored. This study aims to investigate whether a dietary intervention based on a typical Mediterranean Diet enriched with fermented foods (MedDiet +) can impact the gut microbiota, intestinal permeability, and RA-related outcomes.

METHODS

One hundred RA patients are being recruited at Unidade Local de Saúde (ULS) Santa Maria in Lisbon, Portugal, and randomly assigned to either the intervention (MedDiet +) or the control group. The 12-week nutritional intervention includes a personalised dietary plan following the MedDiet + pattern, along with educational resources, food basket deliveries, and clinical culinary workshops, all developed and monitored weekly by registered dietitians. The control group receives standardised general healthy diet recommendations at baseline. The intervention's effects will be assessed by evaluating disease activity, functional status, quality of life, intestinal permeability, endotoxemia, inflammatory biomarkers, intestinal and oral microbiota, serum proteomics, and serum glycome profile characterisation.

DISCUSSION

We anticipate obtaining integrative insights into the interplay between diet, the gut, and RA, while also exploring the underlying mechanisms driving these changes. This study, conducted by a multidisciplinary research team of registered dietitians, rheumatologists, biologists, and immunologists, aims to bridge the current gap between nutrition-related knowledge and RA.

TRIAL REGISTRATION

Registered in ClinicalTrials.gov (NCT06758817; date of registry: January 6th 2025).

Impact of combination chemotherapy with praziquantel and gentamicin or doxycycline on acute hepatic and intestinal schistosomiasis in BALB/c mice

BACKGROUND AND AIMS

Marked divergences in the immunological mechanisms that regulate the pathophysiology of acute and chronic schistosomiasis have a direct influence on pathological outcomes and antiparasitic chemotherapy responses at different stages of Schistosoma mansoni infection. In that way, this study evaluated the impact of combination antiparasitic chemotherapy, involving gentamicin (GEN) and doxycycline (DOX) in combination with praziquantel (PZQ) on the development of acute hepatic and intestinal schistosomiasis in mice.

METHODS

BALB/cmice were randomized into five experimental groups, and the formation of hepatic and intestinal granulomas was evaluated by histopathological and histomorphometric analyses, quantification of hepatic parasite load, and biochemical parameters (ALT, AST, ALP, and albumin).

MAIN FINDINGS

PZQ + DOX combination potentiated hepatic granulomatous inflammation, diffuse fibrosis and ALT circulating levels, indicating greater morphofunctional liver damage. AST levels were increased in PZQ + GEN-treated animals. This response corroborated the histopathological findings, indicating an accelerated modulation towards the chronic phase as manifested by reduced granuloma size compared to infected untreated animals.

CONCLUSION

PZQ combination with DOX and GEN induced differential modulation of the granulomatous inflammation, with DOX aggravating this process and GEN exerting protective effects by accelerating schistosomiasis resolution in S. mansoni-infected mice.

From big data and experimental models to clinical trials: Iterative strategies in microbiome research

Microbiome research has expanded significantly in the last two decades, yet translating findings into clinical applications remains challenging. This perspective discusses the persistent issue of correlational studies in microbiome research and proposes an iterative method leveraging in silico, in vitro, ex vivo, and in vivo studies toward successful preclinical and clinical trials. The evolution of research methodologies, including the shift from small cohort studies to large-scale, multi-cohort, and even "meta-cohort" analyses, has been facilitated by advancements in sequencing technologies, providing researchers with tools to examine multiple health phenotypes within a single study. The integration of multi-omics approaches-such as metagenomics, metatranscriptomics, metaproteomics, and metabolomics-provides a comprehensive understanding of host-microbe interactions and serves as a robust hypothesis generator for downstream in vitro and in vivo research. These hypotheses must then be rigorously tested, first with proof-of-concept experiments to clarify the causative effects of the microbiota, and then with the goal of deep mechanistic understanding. Only following these two phases can preclinical studies be conducted with the goal of translation into the clinic. We highlight the importance of combining traditional microbiological techniques with big-data approaches, underscoring the necessity of iterative experiments in diverse model systems to enhance the translational potential of microbiome research.

Ex Vivo Analysis of the Effect of Endoscopic Premedications on the Microbiota Profile in Gastric Juice

Background and Aim

Dimethicone (GAS), lidocaine (XYL), and protease (PRO) are commonly used as premedications during esophagogastroduodenoscopy (EGD). However, the effects of these drugs on the gastric microbiota remain unexplored. Therefore, we aimed to investigate the effects of these premedications on gastric juice collected from patients undergoing EGD.

Methods

Gastric juice was endoscopically aspirated from six patients and divided into six aliquots for in vitro analysis. The samples were mixed with premedications in corresponding treatment sets: GAS, XYL, PRO, MIX (a mixture of GAS, XYL, and PRO), and control (CTL1 and 2; no medication treatment). After extraction of microbial DNA from the treated samples, the 16S rRNA amplicon sequence was analyzed to determine the microbiota profile in terms of (1) the amount of genomic DNA (gDNA), (2) α-diversity indices, Shannon index, number of observed operational taxonomic units (OTUs), and Chao1 index, (3) weighted and unweighted UniFrac distances, and (4) the relative abundance of phyla and genera.

Results

The total amount of extracted gDNA did not significantly differ between the six groups. The α-diversity indices did not significantly differ between treatment groups. Although GAS, PRO, and MIX differed significantly from the technical replicates in the weighted UniFrac distance (p = 0.03 all), no significant difference was observed in the unweighted UniFrac distance. However, significant differences were observed in the relative abundance of several bacterial microbiota at the phylum and genus levels.

Conclusions

Premedications affect the microbiota profile of specific phylum- and genus-level bacterial groups. Trial Registration: University Hospital Medical Information Network Clinical Trials Registry: UMIN-CTR 000040192 and UMIN-CTR 000051289.

Failure or future? Exploring alternative antibacterials: a comparative analysis of antibiotics and naturally derived biopolymers

The global crisis of antimicrobial resistance (AMR) is escalating due to the misuse and overuse of antibiotics, the slow development of new therapies, and the rise of multidrug-resistant (MDR) infections. Traditional antibiotic treatments face limitations, including the development of resistance, disruption of the microbiota, adverse side effects, and environmental impact, emphasizing the urgent need for innovative alternative antibacterial strategies. This review critically examines naturally derived biopolymers with intrinsic (essential feature) antibacterial properties as a sustainable, next-generation alternative to traditional antibiotics. These biopolymers may address bacterial resistance uniquely by disrupting bacterial membranes rather than cellular functions, potentially reducing microbiota interference. Through a comparative analysis of the mechanisms and applications of antibiotics and antibacterial naturally derived biopolymers, this review highlights the potential of such biopolymers to address AMR while supporting human and environmental health.

Gut microbiota changes are associated with abnormal metabolism activity in children and adolescents with obsessive-compulsive disorder

Obsessive-compulsive disorder (OCD) is a chronic and disabling psychiatric disorder characterized by recurrent intrusive thoughts or repetitive behaviors. We sought to better understand the structure of gut microbiota in first visit registration, treatment-naive children and adolescents with OCD, and the relationship between gut microbiota and fecal metabolites. Thus we studied the gut microbial population using 16 S rRNA sequencing in 49 children (8-17 years of age) with OCD, 42 healthy controls (HCs). We found a significant decrease in α-diversity in the OCD group, and the OCD and HC groups had distinctive intestinal flora. To further investigate the potential interaction effects between OCD and functional pathways of the intestinal flora, the 19 OCD patients and 18 aged-matched HCs were selected to undergo metagenomics analysis. We showed that several functional pathways of gut microbiota in patients with OCD were disrupted, such as glucolipid metabolism, amino acid metabolism, steroid biosynthesis, and the second messenger system. Changes in the clinical characteristics of OCD patients were associated with specific bacteria. Metabolomics analysis was also performed on stool samples from 91 subjects. Intestinal microflora metabolite expression in OCD patients was disturbed, and the related metabolic pathway functions were abnormal. Abnormal metabolites of gut microbiota in OCD patients are mainly involved in folate biosynthesis, the prion disease pathway, and the amino acid metabolic network. This study detailed the intestinal microbiota of children and adolescents with OCD. Our study suggests possible modalities for early OCD intervention by targeting the specific bacteria associated with neurotransmitter metabolism.

Chicory supplementation improves growth performance in juvenile ostriches potentially by attenuating enteritis

Introduction

Enteritis and dysbiosis are the major causes of high morbidity and mortality of juvenile ostriches. Chicory (CC) has been proven to have excellent antioxidant, anti-inflammatory, and antibacterial activities. However, it's unclear whether CC could improve the survival rate of juvenile ostriches by relieving enteritis and correcting dysbiosis.

Materials and methods

South African ostrich hatchlings (Struthio camelus domesticus) were fed with and without a CC-supplemented diet, and the body weight gain and mortality were compared over 4 months of age. Fresh fecal samples of clinically healthy ostriches were collected, and 16S DNAs were analyzed. Moreover, ostrich chicks with LPS-induced enteritis were fed with different dosages (0, 20, 40, and 80 mg/kg) of chicoric acid (CA), a major bioactive component of CC, for five consecutive days. The expression levels of tight junction (TJ)-related proteins and inflammatory mediators in the ilea were detected with western blot and immunofluorescence.

Results

The ostrich chicks fed on the CC-supplemented diet began to increase in weight at the 1st month of age and became remarkably heavier at the fourth month (p < 0.01) compared with those fed on the non-CC-supplemented diet. Additionally, the mortality percentage was lower in the chicks fed on the CC-supplemented diet than those fed on the non-CC-supplemented diet (19% vs. 36%, respectively). The diet with the CC supplementation significantly increased the abundance of Phascolactobacteria (linear discriminant analysis; LDA >4) and Bacteroidota (26.7% vs. 17.7%, respectively) as well as decreased the enrichment of Clostridium (5.0% vs. 9.1%, respectively) in the ostrich ilea compared to the diet without CC. The supplementation of CA at a dose of 80 mg/kg significantly increased the expression level of ZO-1 and claudin-3 (p < 0.0001) and suppressed the levels of IL-1β, IL-6, and TNF-α (p < 0.0001) in ostriches with LPS-induced ileitis.

Conclusion

Our results substantiate that CC or CA supplementation in a diet could effectively improve growth performance and reduce mortality in juvenile ostriches via modulating the gut microbiota and attenuating enteritis.

The role of the gut microbiome in neuroinflammation and chemotherapy-induced peripheral neuropathy

Chemotherapy-induced peripheral neuropathy (CIPN) is one of the most debilitating adverse effects caused by chemotherapy drugs such as paclitaxel, oxaliplatin and vincristine. It is untreatable and often leads to the discontinuation of cancer therapy and a decrease in the quality of life of cancer patients. It is well-established that neuroinflammation and the activation of immune and glial cells are among the major drivers of CIPN. However, these processes are still poorly understood, and while many chemotherapy drugs alone can drive the activation of these cells and consequent neuroinflammation, it remains elusive to what extent the gut microbiome influences these processes. In this review, we focus on the peripheral mechanisms driving CIPN, and we address the bidirectional pathways by which the gut microbiome communicates with the immune and nervous systems. Additionally, we critically evaluate literature addressing how chemotherapy-induced dysbiosis and the consequent imbalance in bacterial products may contribute to the activation of immune and glial cells, both of which drive neuroinflammation and possibly CIPN development, and how we could use this knowledge for the development of effective treatment strategies.

Situations predisposing primary care patients to use antibiotics without a prescription in the United States

Background

Patients' situations can impact their intentions to use antibiotics without medical guidance (non-prescription use) in the future. This survey determines the prevalence of intended (future) use of non-prescription antibiotics for 13 predefined situations and identifies the sociodemographic characteristics associated with intended use for these types of situations.

Methods

Patient surveys (N = 564) were conducted from January 2020 to June 2021 in the waiting rooms of 6 safety-net primary care clinics and 2 emergency departments in a private healthcare system. We used principal component analysis to identify 3 situational summary factors: barriers to a doctor visit, accessibility of non-prescription antibiotics, and previous symptom relief with antibiotics. Multivariate linear regression identified the sociodemographic predictors associated with each summary factor.

Results

The most common situations triggering patients to use non-prescription antibiotics were a perceived high cost of doctor visits (29.8%), having leftover prescription antibiotics (50.4%), and experiencing symptom relief with prior use of antibiotics (47.5%). Multivariate regression results revealed that younger patients (P < 0.04) and patients attending the safety-net health system (P < 0.001) had more intended use of non-prescription antibiotics for all 3 summary factors.

Conclusions

Future stewardship interventions should consider the types of situations that drive patients' decisions to use antibiotics without a prescription. Interventions aimed at reducing barriers to health care (eg, high costs and long waits associated with doctor appointments) and educating individuals on medically appropriate, nonantibiotic treatment options may reduce antibiotic use and antimicrobial resistance.

The Influence of Cecal Microbiota Transplantation on Chicken Injurious Behavior: Perspective in Human Neuropsychiatric Research

Numerous studies have evidenced that neuropsychiatric disorders (mental illness and emotional disturbances) with aggression (or violence) pose a significant challenge to public health and contribute to a substantial economic burden worldwide. Especially, social disorganization (or social inequality) associated with childhood adversity has long-lasting effects on mental health, increasing the risk of developing neuropsychiatric disorders. Intestinal bacteria, functionally as an endocrine organ and a second brain, release various immunomodulators and bioactive compounds directly or indirectly regulating a host's physiological and behavioral homeostasis. Under various social challenges, stress-induced dysbiosis increases gut permeability causes serial reactions: releasing neurotoxic compounds, leading to neuroinflammation and neuronal injury, and eventually neuropsychiatric disorders associated with aggressive, violent, or impulsive behavior in humans and various animals via a complex bidirectional communication of the microbiota-gut-brain (MGB) axis. The dysregulation of the MGB axis has also been recognized as one of the reasons for the prevalence of social stress-induced injurious behaviors (feather pecking, aggression, and cannibalistic pecking) in chickens. However, existing knowledge of preventing and treating these disorders in both humans and chickens is not well understood. In previous studies, we developed a non-mammal model in an abnormal behavioral investigation by rationalizing the effects of gut microbiota on injurious behaviors in chickens. Based on our earlier success, the perspective article outlines the possibility of reducing stress-induced injurious behaviors in chickens through modifying gut microbiota via cecal microbiota transplantation, with the potential for providing a biotherapeutic rationale for preventing injurious behaviors among individuals with mental disorders via restoring gut microbiota diversity and function.

The predicted mechanisms and evidence of probiotics on type 2 diabetes mellitus (T2DM)

Type 2 diabetes mellitus (T2DM) is a serious endocrine and metabolic disease that is highly prevalent and causes high mortality and morbidity rates worldwide. This review aims to focus on the potential of probiotics in the management of T2DM and its complications and to summarise the various mechanisms of action of probiotics with respect to T2DM. In this review, experimental studies conducted between 2016 and 2022 were explored. The possible mechanisms of action are based on their ability to modulate the gut microbiota, boost the production of short-chain fatty acids (SCFAs) and glucagon-like peptides, inhibit α-glucosidase, elevate sirtuin 1 (SIRT1) levels while reducing fetuin-A levels, and regulate the level of inflammatory cytokines. This review recommends carrying out further studies, especially human trials, to provide robust evidence-based knowledge on the use of probiotics for the treatment of T2DM.IMPACT STATEMENTT2DM is prevalent worldwide causing high rates of morbidity and mortality.Gut microbiota play a significant role in the pathogenesis of T2DM.Probiotics can be used as possible therapeutic tools for the management of T2DM.The possible mechanisms of action of probiotics include modulation of the gut microbiota, production of SCFAs and glucagon-like peptides, inhibition of α-glucosidase, raising SIRT1, reducing fetuin-A levels, and regulating the level of inflammatory cytokines.

Scutellaria baicalensis Georgi alleviates Clostridium difficile associated diarrhea and its modulatory effects on the gut microbiota

The growing incidence of Clostridium difficile associated diarrhea (CDAD) underscores the urgency for potent treatments. This research delves into the therapeutic potential of Scutellaria baicalensis Georgi (Lamiaceae) root (SR) in addressing CDAD and its influence on gut microbiota. Using a CDAD mouse model and fidaxomicin as a control, SR's impact was measured through diarrhea symptoms, colonic histopathology, and C. difficile toxin levels. Employing the PacBio platform, 16S rRNA full-length gene sequencing analyzed the gut microbial composition and the effect of SR. Results revealed SR considerably alleviated diarrhea during treatment and restoration phases, with a marked decrease in colonic inflammation. C. difficile toxin levels dropped significantly with SR treatment (P < 0.001). While SR didn't augment gut microbiota's overall abundance, it enhanced its diversity. It restored levels of Proteobacteria and Bacteroidetes, reduced Akkermansia spp. and Enterococcus spp. proportions, and modulated specific bacterial species' abundance. In essence, SR effectively mitigates CDAD symptoms, curtails inflammatory reactions, and beneficially restructures gut microbiota, suggesting its potential in advanced CDAD clinical intervention.

Facemask acne attenuation through modulation of indirect microbiome interactions

During the COVID-19 pandemic, facemasks played a pivotal role in preventing person-person droplet transmission of viral particles. However, prolonged facemask wearing causes skin irritations colloquially referred to as 'maskne' (mask + acne), which manifests as acne and contact dermatitis and is mostly caused by pathogenic skin microbes. Previous studies revealed that the putative causal microbes were anaerobic bacteria, but the pathogenesis of facemask-associated skin conditions remains poorly defined. We therefore characterized the role of the facemask-associated skin microbiota in the development of maskne using culture-dependent and -independent methodologies. Metagenomic analysis revealed that the majority of the facemask microbiota were anaerobic bacteria that originated from the skin rather than saliva. Previous work demonstrated direct interaction between pathogenic bacteria and antagonistic strains in the microbiome. We expanded this analysis to include indirect interaction between pathogenic bacteria and other indigenous bacteria classified as either 'pathogen helper (PH)' or 'pathogen inhibitor (PIn)' strains. In vitro screening of bacteria isolated from facemasks identified both strains that antagonized and promoted pathogen growth. These data were validated using a mouse skin infection model, where we observed attenuation of symptoms following pathogen infection. Moreover, the inhibitor of pathogen helper (IPH) strain, which did not directly attenuate pathogen growth in vitro and in vivo, functioned to suppress symptom development and pathogen growth indirectly through PH inhibitory antibacterial products such as phenyl lactic acid. Taken together, our study is the first to define a mechanism by which indirect microbiota interactions under facemasks can control symptoms of maskne by suppressing a skin pathogen.

Black seed oil reverses chronic antibiotic-mediated depression and social behaviour deficits via modulation of hypothalamic mitochondrial-dependent markers and insulin expression

Chronic antibiotic use has been reported to impair mitochondrial indices, hypothalamus-mediated metabolic function, and amygdala-regulated emotional processes. Natural substances such as black seed (Nigella sativa) oil could be beneficial in mitigating these impairments. This study aimed to assess the impact of black seed oil (NSO) on depression and sociability indices, redox imbalance, mitochondrial-dependent markers, and insulin expression in mice subjected to chronic ampicillin exposure. Forty adult male BALB/c mice (30 ± 2 g) were divided into five groups: the CTRL group received normal saline, the ABT group received ampicillin, the NSO group received black seed oil, the ABT/NSO group concurrently received ampicillin and black seed oil, and the ABT+NSO group experienced pre-exposure to ampicillin followed by subsequent treatment with black seed oil. The ampicillin-exposed group exhibited depressive-like behaviours, impaired social interactive behaviours, and disruptions in mitochondrial-dependent markers in plasma and hypothalamic tissues, accompanied by an imbalance in antioxidant levels. Moreover, chronic antibiotic exposure downregulated insulin expression in the hypothalamus. However, these impairments were significantly ameliorated in the ABT/NSO, and ABT+NSO groups compared to the untreated antibiotic-exposed group. Overall, findings from this study suggest the beneficial role of NSO as an adjuvant therapy in preventing and abrogating mood behavioural and neural-metabolic impairments of chronic antibiotic exposure.

Approach to the diagnosis and management of dysbiosis

All microorganisms like bacteria, viruses and fungi that reside within a host environment are considered a microbiome. The number of bacteria almost equal that of human cells, however, the genome of these bacteria may be almost 100 times larger than the human genome. Every aspect of the physiology and health can be influenced by the microbiome living in various parts of our body. Any imbalance in the microbiome composition or function is seen as dysbiosis. Different types of dysbiosis are seen and the corresponding symptoms depend on the site of microbial imbalance. The contribution of the intestinal and extra-intestinal microbiota to influence systemic activities is through interplay between different axes. Whole body dysbiosis is a complex process involving gut microbiome and non-gut related microbiome. It is still at the stage of infancy and has not yet been fully understood. Dysbiosis can be influenced by genetic factors, lifestyle habits, diet including ultra-processed foods and food additives, as well as medications. Dysbiosis has been associated with many systemic diseases and cannot be diagnosed through standard blood tests or investigations. Microbiota derived metabolites can be analyzed and can be useful in the management of dysbiosis. Whole body dysbiosis can be addressed by altering lifestyle factors, proper diet and microbial modulation. The effect of these interventions in humans depends on the beneficial microbiome alteration mostly based on animal studies with evolving evidence from human studies. There is tremendous potential for the human microbiome in the diagnosis, treatment, and prognosis of diseases, as well as, for the monitoring of health and disease in humans. Whole body system-based approach to the diagnosis of dysbiosis is better than a pure taxonomic approach. Whole body dysbiosis could be a new therapeutic target in the management of various health conditions.

The impact of antibiotic exposure on antibiotic resistance gene dynamics in the gut microbiota of inflammatory bowel disease patients

Background

While antibiotics are commonly used to treat inflammatory bowel disease (IBD), their widespread application can disturb the gut microbiota and foster the emergence and spread of antibiotic resistance. However, the dynamic changes to the human gut microbiota and direction of resistance gene transmission under antibiotic effects have not been clearly elucidated.

Methods

Based on the Human Microbiome Project, a total of 90 fecal samples were collected from 30 IBD patients before, during and after antibiotic treatment. Through the analysis workflow of metagenomics, we described the dynamic process of changes in bacterial communities and resistance genes pre-treatment, during and post-treatment. We explored potential consistent relationships between gut microbiota and resistance genes, and established gene transmission networks among species before and after antibiotic use.

Results

Exposure to antibiotics can induce alterations in the composition of the gut microbiota in IBD patients, particularly a reduction in probiotics, which gradually recovers to a new steady state after cessation of antibiotics. Network analyses revealed intra-phylum transfers of resistance genes, predominantly between taxonomically close organisms. Specific resistance genes showed increased prevalence and inter-species mobility after antibiotic cessation.

Conclusion

This study demonstrates that antibiotics shape the gut resistome through selective enrichment and promotion of horizontal gene transfer. The findings provide insights into ecological processes governing resistance gene dynamics and dissemination upon antibiotic perturbation of the microbiota. Optimizing antibiotic usage may help limit unintended consequences like increased resistance in gut bacteria during IBD management.

Effect of tebipenem pivoxil hydrobromide on the normal gut microbiota of a healthy adult population in Sweden: a randomised controlled trial

BACKGROUND

Antimicrobials cause perturbations in the composition and diversity of the host microbiome. We aimed to compare gut microbiome perturbations caused by oral tebipenem pivoxil hydrobromide (a novel carbapenem) and by amoxicillin-clavulanic acid (an orally administered β-lactam-β-lactam inhibitor combination widely used in clinical practice).

METHODS

We did a phase 1, single-centre, randomised, parallel-group, active-control trial to evaluate the effect of tebipenem pivoxil hydrobromide on the human gut microbiota. Healthy participants aged 18 years or older with no documented illnesses during recruitment were enrolled at Karolinska University Hospital (Stockholm, Sweden). Study participants were stratified by sex and block-randomised in a 1:1 ratio to treatment with either tebipenem pivoxil hydrobromide (600 mg orally every 8 h) or amoxicillin-clavulanic acid (500 mg amoxicillin and 125 mg clavulanic acid orally every 8 h). The study included 10 days of treatment (days 1-10) and four follow-up visits (days 14, 21, 90, and 180). The trial was open-label for clinical investigators and patients, but masked for microbiology investigators. Faecal samples were collected at all visits. Sequencing of 16S rDNA was used to measure the diversity metrics, and quantitative culture to quantify selected taxa. The primary outcomes were changes in the α and β diversity and log count of colony-forming units for selected taxa between samples compared with baseline (day 1), and whether any changes reverted during the follow-up period. The analyses were done in the intention-to-treat population. This study was registered with ClinicalTrials.gov (NCT04376554).

FINDINGS

The study was conducted between Jan 23, 2020, and April 6, 2021. 49 volunteers were screened for eligibility, among whom 30 evaluable participants (14 men and 16 women) were assigned: 15 (50%) to the tebipenem pivoxil hydrobromide group and 15 (50%) to the amoxicillin-clavulanic acid group. Baseline characteristics were similar between groups. Complete follow-up was available for all participants, and all participants except one completed treatment as assigned. The diversity metrics showed significant changes from baseline during the treatment period. Significant decreases in richness were observed on days 4-10 (p≤0·0011) in the amoxicillin-clavulanic acid group and on days 4-14 (p≤0·0019) in the tebipenem pivoxil hydrobromide group. Similarly, evenness was significantly decreased during treatment in the amoxicillin-clavulanic acid group (day 4, p=0·030) and the tebipenem pivoxil hydrobromide group (days 4-10, p<0·0001) compared with baseline. Quantitative cultures showed significant decreases in Enterobacterales (days 4-7, p≤0·0030), Enterococcus spp (days 4-14, p=0·025 to p<0·0001), Bifidobacterium spp (days 2-4, p≤0·026), and Bacteroides spp (days 4-10, p≤0·030) in the tebipenem pivoxil hydrobromide group. Similarly, in amoxicillin-clavulanic acid recipients, significant changes were observed in Enterobacterales (days 4-10, p≤0·048), Bifidobacterium spp (days 2-4, p≤0·013), and Lactobacillus spp (days 2-4, p≤0·020). Samples from the follow-up period were not significantly different from those at baseline in β diversity analysis (PERMANOVA, p>0·99). By the end of the study, no significant change was observed compared with baseline in either group. There were no deaths or severe adverse events.

INTERPRETATION

The impact of tebipenem pivoxil hydrobromide on the gut microbiome was similar to that of amoxicillin-clavulanic acid. The safety of antibiotic use with regard to the microbiome should be given attention, as dysbiosis is associated with health and disease.

FUNDING

Spero Therapeutics.

Characterization of Genomic, Physiological, and Probiotic Features of Lactiplantibacillus plantarum JS21 Strain Isolated from Traditional Fermented Jiangshui

This study aimed to understand the genetic and metabolic traits of a Lactiplantibacillus plantarum JS21 strain and its probiotic abilities through laboratory tests and computer analysis. L. plantarum JS21 was isolated from a traditional fermented food known as "Jiangshui" in Hanzhong city. In this research, the complete genetic makeup of JS21 was determined using Illumina and PacBio technologies. The JS21 genome consisted of a 3.423 Mb circular chromosome and five plasmids. It was found to contain 3023 protein-coding genes, 16 tRNA genes, 64 rRNA operons, 40 non-coding RNA genes, 264 pseudogenes, and six CRISPR array regions. The GC content of the genome was 44.53%. Additionally, the genome harbored three complete prophages. The evolutionary relationship and the genome collinearity of JS21 were compared with other L. plantarum strains. The resistance genes identified in JS21 were inherent. Enzyme genes involved in the Embden-Meyerhof-Parnas (EMP) and phosphoketolase (PK) pathways were detected, indicating potential for facultative heterofermentative pathways. JS21 possessed bacteriocins plnE/plnF genes and genes for polyketide and terpenoid assembly, possibly contributing to its antibacterial properties against Escherichia coli (ATCC 25922), Escherichia coli (K88), Staphylococcus aureus (CMCC 26003), and Listeria monocytogenes (CICC 21635). Furthermore, JS21 carried genes for Na+/H+ antiporters, F0F1 ATPase, and other stress resistance genes, which may account for its ability to withstand simulated conditions of the human gastrointestinal tract in vitro. The high hydrophobicity of its cell surface suggested the potential for intestinal colonization. Overall, L. plantarum JS21 exhibited probiotic traits as evidenced by laboratory experiments and computational analysis, suggesting its suitability as a dietary supplement.

The connection between epigenetics and gut microbiota-current perspective

Both the epigenetic changes and gut microbiota (GM) have attracted a growing interest in establishing effective diagnostics and potential therapeutic strategies for a number of diseases. These disorders include metabolic, central nervous system-related diseases, autoimmune, and gastrointestinal infections (GI). Despite the number of studies, there is no extensive review that connects the epigenetics modifications and GM as biomarkers that could confer effective diagnostics and confer treatment options. To this end, this review hopes to give detailed information on connecting the modifications in epigenetic and GM. An updated and detailed information on the connection between the epigenetics factors and GM that influence diseases are given. In addition, the review showed some associations between the epigenetics to the maternal GM and offspring health. Finally, the limitations of the concept and prospects into this new emerging discipline were also looked into. Although this review elucidated on the maternal diet and response to offspring health with respect to GM and epigenetic modifications, there still exist various limitations to this newly emerging discipline. In addition to integrating complementary multi-omics data, longitudinal sampling will aid with the identification of functional mechanisms that may serve as therapeutic targets. To this end, this review gave a detailed perspective into harnessing disease diagnostics, prevention and treatment options through epigenetics and GM.

Gut Microbiota-Gut Metabolites and Clostridioides difficile Infection: Approaching Sustainable Solutions for Therapy

Clostridioides difficile (C. difficile) infection (CDI) is the most common hospital-acquired infection. With the combination of a high rate of antibiotic resistance and recurrence, it has proven to be a debilitating public health threat. Current treatments for CDI include antibiotics and fecal microbiota transplantation, which contribute to recurrent CDIs and potential risks. Therefore, there is an ongoing need to develop new preventative treatment strategies for CDI. Notably, gut microbiota dysbiosis is the primary risk factor for CDI and provides a promising target for developing novel CDI therapy approaches. Along with gut microbiota dysbiosis, a reduction in important gut metabolites like secondary bile acids and short-chain fatty acids (SCFAs) were also seen in patients suffering from CDI. In this review study, we investigated the roles and mechanisms of gut microbiota and gut microbiota-derived gut metabolites, especially secondary bile acids and SCFAs in CDI pathogenesis. Moreover, specific signatures of gut microbiota and gut metabolites, as well as different factors that can modulate the gut microbiota, were also discussed, indicating that gut microbiota modulators like probiotics and prebiotics can be a potential therapeutic strategy for CDI as they can help restore gut microbiota and produce gut metabolites necessary for a healthy gut. The understanding of the associations between gut microbiota-gut metabolites and CDI will allow for developing precise and sustainable approaches, distinct from antibiotics and fecal transplant, for mitigating CDI and other gut microbiota dysbiosis-related diseases.

The Efficacy of a Mix of Probiotics (Limosilactobacillus reuteri LMG P-27481 and Lacticaseibacillus rhamnosus GG ATCC 53103) in Preventing Antibiotic-Associated Diarrhea and Clostridium difficile Infection in Hospitalized Patients: Single-Center, Open-Label, Randomized Trial

BACKGROUND

Antibiotic-associated diarrhea is a condition reported in 5-35% of patients treated with antibiotics, especially in older patients with comorbidities. In most cases, antibiotic-associated diarrhea is not associated with serious complications, but it can prolong hospitalization and provoke Clostridium difficile infection. An important role in the prevention of antibiotic-associated diarrhea is carried out by some probiotic strains such as Lactobacillus GG or the yeast Saccharomyces boulardii that showed good efficacy and a significant reduction in antibiotic-associated diarrhea. Similarly, the Limosilactobacillus reuteri DSM 17938 showed significant benefits in acute diarrhea, reducing its duration and abdominal pain.

AIM

The aim of this study was to test the efficacy of a mix of two probiotic strains (Limosilactobacillus reuteri LMG P-27481 and Lacticaseibacillus rhamnosus GG ATCC 53103; Reuterin GG®, NOOS, Italy), in association with antibiotics (compared to antibiotics used alone), in reducing antibiotic-associated diarrhea, clostridium difficile infection, and other gastrointestinal symptoms in adult hospitalized patients.

PATIENTS AND METHODS

We enrolled 113 (49M/64F, mean age 69.58 ± 21.28 years) adult patients treated with antibiotics who were hospitalized at the Internal Medicine Department of the San Carlo di Nancy Hospital in Rome from January 2023 to September 2023. Patients were randomized to receive probiotics 1.4 g twice/day in addition with antibiotics (Reuterin GG® group, total: 56 patients, 37F/19M, 67.16 ± 20.5 years old) or antibiotics only (control group, total: 57 patients, 27F/30 M, 71 ± 22 years old).

RESULTS

Patients treated with Reuterin GG® showed a significant reduction in diarrhea and clostridium difficile infection. In particular, 28% (16/57) of patients in the control group presented with diarrhea during treatment, compared with 11% (6/56) in the probiotic group (p < 0.05). Interestingly, 7/57 (11%) of patients treated only with antibiotics developed clostridium difficile infection compared to 0% in the probiotic group (p < 0.01). Finally, 9% (5/57) of patients in the control group presented with vomiting compared with 2% (1/56) in the probiotic group (p < 0.05).

CONCLUSIONS

Our study showed, for the first time, the efficacy of these two specific probiotic strains in preventing antibiotic-associated diarrhea and clostridium difficile infection in adult hospitalized patients treated with antibiotic therapy. This result allows us to hypothesize that the use of specific probiotic strains during antibiotic therapy can prevent dysbiosis and subsequent antibiotic-associated diarrhea and clostridium difficile infection, thus resulting in both patient and economic health care benefits.

Anti-oxidant effects of herbal residue from Shengxuebao mixture on heat-stressed New Zealand rabbits

Heat stress can lead to hormonal imbalances, weakened immune system, increased metabolic pressure on the liver, and ultimately higher animal mortality rates. This not only seriously impairs the welfare status of animals, but also causes significant economic losses to the livestock industry. Due to its rich residual bioactive components and good safety characteristics, traditional Chinese medicine (TCM) residue is expected to become a high-quality feed additive with anti-oxidative stress alleviating function. This study focuses on the potential of Shengxuebao mixture herbal residue (SXBR) as an anti-heat stress feed additive. Through the UPLC (ultra performance liquid chromatography) technology, the average residue rate of main active ingredients from SXBR were found to be 25.39%. SXBR were then added into the basal diet of heat stressed New Zealand rabbits at the rates of 5% (SXBRl), 10% (SXBRm) and 20% (SXBRh). Heat stress significantly decreased the weight gain, as well as increased neck and ear temperature, drip loss in meat, inflammation and oxidative stress. Also, the hormone levels were disrupted, with a significant increase in serum levels of CA, COR and INS. After the consumption of SXBR in the basal diet for 3 weeks, the weight of New Zealand rabbits increased significantly, and the SXBRh group restored the redness value of the meat to a similar level as the control group. Furthermore, the serum levels T3 thyroid hormone in the SXBRh group and T4 thyroid hormone in the SXBRm group increased significantly, the SXBRh group showed a significant restoration in inflammation markers (IL-1β, IL-6, and TNF-α) and oxidative stress markers (total antioxidant capacity, HSP-70, MDA, and ROS) levels. Moreover, the real-time fluorescence quantitative PCR analysis found that, the expression levels of antioxidant genes such as Nrf2, HO-1, NQO1, and GPX1 were significantly upregulated in the SXBRh group, and the expression level of the Keap1 gene was significantly downregulated. Additionally, the SXBRm group showed significant upregulation in the expression levels of HO-1 and NQO1 genes. Western blot experiments further confirmed the up-regulation of Nrf2, Ho-1 and NQO1 proteins. This study provides a strategy for the utilization of SXBR and is of great significance for the green recycling of the TCM residues, improving the development of animal husbandry and animal welfare.

Effect of potassium-competitive acid blockers on human gut microbiota: a systematic review and meta-analysis

Background: Vonoprazan has been reported to exert more potent and long-lasting gastric acid inhibition than proton pump inhibitors, potentially leading to a greater impact on the gut microbiota. This study aimed to clarify changes in microbial diversity and bacterial composition after VPZ treatments. Methods: We searched from PubMed, Embase, WOS, Scopus, Cochrane Library, and ClinicalTrials.gov (all years up to May 2023). The primary outcomes were alpha and beta diversity, as well as differences in gut microbiota composition between before and after VPZ treatments. We performed a meta-analysis to uncover the potential changes in human gut microbiota among VPZ users by pooled mean difference (MD) with a 95% confidence interval (CI). The risk of bias was assessed using the ROBINS-I tool. Results: A total of 12 studies were included to compare differences before and after VPZ treatments. Compared with baseline, alpha diversity was significantly reduced after VPZ treatments and gradually returned to baseline with longer follow-up. At the phylum level, there was a decrease in the relative abundance of Firmicutes and Actinobacteria, while Bacteroidetes increased compared with baseline. At the genus level, we found a significant decrease in the relative abundance of Coprococcus and Bifidobacterium and a significant increase in the relative abundance of Bacteroides compared with those before treatment. In subgroup analyses according to country and participants, we found differences in microbial changes after VPZ treatments. Conclusion: Vonoprazan can affect the changes of gut microbiota, which may be potentially associated with its strong ability of acid inhibition. However, due to the large heterogeneity, further studies are required to validate these findings. Systematic Review Registration: https://www.crd.york.ac.uk/prospero/, identifier CRD42023412265.

Biomaterial therapeutic strategies for treatment of bacterial lung infections

Bacterial infections of the lung frequently occur as a secondary infection to many respiratory viral infections and conditions, including influenza, COVID-19, chronic obstructive pulmonary disease (COPD), and cystic fibrosis (CF). Currently, clinical standard treats bacterial infections of the lung with antibiotic drugs. However, the use of broad-spectrum antibiotics can disrupt host microbiomes, lead to patient discomfort, and current clinical settings face the constantly increasing threat of drug-resistant bacteria. Biofilms further obstruct effective treatment due to their protective matrix layer, which shields bacteria from both the host immune system and antimicrobial drugs and subsequently promotes drug resistance. Alternative antimicrobial agents, including bacteriophages and antimicrobial peptides, have been utilized to treat drug-resistant bacteria. However, these antimicrobial agents have significant limitations pertaining to their ability to arrive at infection sites without compromised function and ability to persist over an extended period to fully treat infections. Enhanced delivery strategies present great promise in addressing these issues by using micro/nanoparticle carriers that shield antimicrobial agents in transit and result in sustained release, enhancing subsequent therapeutic effect and can even be modulated to be multi-functional to further improve recovery following bacterial infection.

Antibiotic-induced collateral damage to the microbiota and associated infections

Antibiotics have transformed medicine, saving millions of lives since they were first used to treat a bacterial infection. However, antibiotics administered to target a specific pathogen can also cause collateral damage to the patient's resident microbial population. These drugs can suppress the growth of commensal species which provide protection against colonization by foreign pathogens, leading to an increased risk of subsequent infection. At the same time, a patient's microbiota can harbour potential pathogens and, hence, be a source of infection. Antibiotic-induced selection pressure can cause overgrowth of resistant pathogens pre-existing in the patient's microbiota, leading to hard-to-treat superinfections. In this Review, we explore our current understanding of how antibiotic therapy can facilitate subsequent infections due to both loss of colonization resistance and overgrowth of resistant microorganisms, and how these processes are often interlinked. We discuss both well-known and currently overlooked examples of antibiotic-associated infections at various body sites from various pathogens. Finally, we describe ongoing and new strategies to overcome the collateral damage caused by antibiotics and to limit the risk of antibiotic-associated infections.

Acculturation and Subjective Norms Impact Non-Prescription Antibiotic Use among Hispanic Patients in the United States

Using antibiotics without medical guidance (non-prescription antibiotic use) may contribute to antimicrobial resistance. Hispanic individuals are a growing demographic group in the United States (US) with a high prevalence of non-prescription antibiotic use. We investigated the effects of acculturation and subjective norms on Hispanic individuals' intentions to use antibiotics without a prescription from the following sources: (1) markets in the United States (not legal), (2) other countries (abroad), (3) leftovers from previous prescriptions, and (4) friends/relatives. We surveyed self-identified Hispanic outpatients in eight clinics from January 2020 to June 2021 using the previously validated Short Acculturation Scale for Hispanics (SASH). Of the 263 patients surveyed, 47% reported previous non-prescription use, and 54% expressed intention to use non-prescription antibiotics if feeling sick. Individuals with lower acculturation (Spanish-speaking preferences) expressed greater intentions to use antibiotics from abroad and from any source. Individuals with more friends/relatives who obtain antibiotics abroad were over 2.5 times more likely to intend to use non-prescription antibiotics from friends/relatives (p = 0.034). Other predictors of intention to use non-prescription antibiotics included high costs of doctor visits and perceived language barriers in the clinic. Antibiotic stewardship interventions in Hispanic communities in the United States should consider the sociocultural and healthcare barriers influencing non-prescription use and promote language-concordant healthcare.

Antibiotic Use Prior to COVID-19 Vaccine Is Associated with Higher Risk of COVID-19 and Adverse Outcomes: A Propensity-Scored Matched Territory-Wide Cohort

Background: Antibiotics may increase the risk of COVID-19 among non-vaccinated subjects via probable gut dysbiosis. We aimed to investigate whether antibiotics also affect the clinical outcomes of COVID-19 vaccine recipients. Methods: This was a territory-wide cohort study of 3,821,302 COVID-19 vaccine recipients (aged ≥ 18 years) with ≥2 doses of either BNT162b2 or CoronaVac. Exclusion criteria included prior COVID-19, prior gastrointestinal surgery, and immunocompromised status. The primary outcome was COVID-19 infection and secondary outcomes included COVID-19-related hospitalization and severe infection (composite of intensive care unit admission, ventilatory support, and/or death). Exposure was pre-vaccination antibiotic use (within 180 days of first vaccine dose). Covariates included age, sex, Charlson Comorbidity Index, and concomitant medication use. Subjects were followed from the index date (first dose vaccination) until outcome occurrence, death, an additional dose of vaccination, or 15 November 2022. Propensity score (PS) matching and a Poisson regression model were used to estimate the adjusted incidence rate ratio (aIRR) of outcomes with antibiotic use. Results: Among 342,338 PS matched three-dose vaccine recipients (mean age: 57.4 years; male: 45.1%) with a median follow-up of 13.6 months (IQR: 9.2-16.3), antibiotics were associated with a higher risk of COVID-19 infection (aIRR: 1.16;95% CI: 1.14-1.19), hospitalization (aIRR: 1.75;95% CI: 1.65-1.86), and severe infection (aIRR: 1.60; 95% CI: 1.21-2.11). Notably, antibiotic use was associated with a higher risk of severe infection and death among CoronaVac recipients (aIRR: 1.62 95% CI: 1.18-2.22 and aIRR: 2.70, 95% CI: 1.54-4.73 for the two secondary outcomes, respectively), but not BNT162b2 recipients. Conclusions: Pre-vaccination use of antibiotics was associated with a higher risk of COVID-19 infection, hospitalization, and severe disease outcomes.

The Lung Microbiome in COPD and Lung Cancer: Exploring the Potential of Metal-Based Drugs

Chronic obstructive pulmonary disease (COPD) and lung cancer 17 are two of the most prevalent and debilitating respiratory diseases worldwide, both associated with high morbidity and mortality rates. As major global health concerns, they impose a substantial burden on patients, healthcare systems, and society at large. Despite their distinct aetiologies, lung cancer and COPD share common risk factors, clinical features, and pathological pathways, which have spurred increasing research interest in their co-occurrence. One area of particular interest is the role of the lung microbiome in the development and progression of these diseases, including the transition from COPD to lung cancer. Exploring novel therapeutic strategies, such as metal-based drugs, offers a potential avenue for targeting the microbiome in these diseases to improve patient outcomes. This review aims to provide an overview of the current understanding of the lung microbiome, with a particular emphasis on COPD and lung cancer, and to discuss the potential of metal-based drugs as a therapeutic strategy for these conditions, specifically concerning targeting the microbiome.

Alteration of gut microbiome and correlated amino acid metabolism are associated with acute myelocytic leukemia carcinogenesis

BACKGROUND

The aim of this study is to investigate the profiles of gut microbiota and metabolites in acute myelocytic leukemia (AML) patients treated with/without chemotherapy.

METHODS

Herein, high-throughput 16S rRNA gene sequencing was performed to analysis gut microbiota profiles, and liquid chromatography and mass spectrometry were performed to analysis metabolites profiles. The correlation between gut microbiota biomarkers identified by LEfSe and differentially expressed metabolites were determined by spearman association analysis.

RESULTS

The results showed the distinguished gut microbiota and metabolites profiles between AML patients and control individuals or AML patients treated with chemotherapy. Compared to normal populations, the ratio of Firmicutes to Bacteroidetes was increased at the phylum level than that in AML patients, and LEfSe analysis identified Collinsella and Coriobacteriaceae as biomarkers of AML patients. Differential metabolite analysis indicated that, compared to AML patients, numerous differential amino acids and analogs could be observed in control individuals and AML patients treated with chemotherapy. Interestingly, spearman association analysis demonstrated that plenty of bacteria biomarkers shows statistical correlations with differentially expressed amino acid metabolites. In addition, we found that both Collinsella and Coriobacteriaceae demonstrate remarkable positive correlation with hydroxyprolyl-hydroxyproline, prolyl-tyrosine, and tyrosyl-proline.

CONCLUSION

In conclusion, our present study investigated the role of the gut-microbiome-metabolome axis in AML and revealed the possibility of AML treatment by gut-microbiome-metabolome axis in the further.

Gut microbiota analyses of inflammatory bowel diseases from a representative Saudi population

BACKGROUND

Crohn's diseases and ulcerative colitis, both of which are chronic immune-mediated disorders of the gastrointestinal tract are major contributors to the overarching Inflammatory bowel diseases. It has become increasingly evident that the pathological processes of IBDs results from interactions between genetic and environmental factors, which can skew immune responses against normal intestinal flora.

METHODS

The aim of this study is to assess and analyze the taxa diversity and relative abundances in CD and UC in the Saudi population. We utilized a sequencing strategy that targets all variable regions in the 16 S rRNA gene using the Swift Amplicon 16 S rRNA Panel on Illumina NovaSeq 6000.

RESULTS

The composition of stool 16 S rRNA was analyzed from 219 patients with inflammatory bowel disease and from 124 healthy controls. We quantified the abundance of microbial communities to examine any significant differences between subpopulations of samples. At the genus level, two genera in particular, Veillonella and Lachnoclostridium showed significant association with CD versus controls. There were significant differences between subjects with CD versus UC, with the top differential genera spanning Akkermansia, Harryflintia, Maegamonas and Phascolarctobacterium. Furthermore, statistically significant taxa diversity in microbiome composition was observed within the UC and CD groups.

CONCLUSIONS

In conclusion we have shown that there are significant differences in gut microbiota between UC, CD and controls in a Saudi Arabian inflammatory bowel disease cohort. This reinforces the need for further studies in large populations that are ethnically and geographically diverse. In addition, our results show the potential to develop classifiers that may have add additional richness of context to clinical diagnosis of UC and CD with larger inflammatory bowel disease cohorts.

The Effect of Dietary Synbiotics in Actively Racing Standardbred Horses Receiving Trimethoprim/Sulfadiazine

Synbiotics are often provided to horses receiving antibiotics to protect against microbiome disturbances, despite a lack of evidence for efficacy. The purpose of this study was to evaluate the effect of a synbiotic product in horses receiving antibiotics. Sixteen actively racing Standardbred horses were randomly allocated (four-way crossover) to one of four groups: antibiotics (10 days; AB), synbiotics (28 days; PROBIOPlus^TM; PBP), PBP + AB, or Control. The fecal microbiome was investigated using 16S rRNA sequencing, and fecal dry matter (DM; %), pH, and scores (FS; 0-9) were measured. Data were analyzed with two-way ANOVA. Results found microbiota differences in community membership between PBP + AB and all other treatments during and after antibiotic treatment. During antibiotic treatment, AB and PBP + AB were significantly different from Control. After antibiotic treatment, PBP + AB was significantly different from all other treatments. The few differences found in relative abundance of phyla or predominant genera were mostly in fiber degrading bacteria. The Fibrobacter population was significantly higher in AB and PBP + AB horses than Control. Unclassified Ruminococcaceae was significantly higher in Control than AB and PBP. After antibiotic treatment, PBP + AB horses were significantly higher than PBP horses. In conclusion, these data provide support for the ability of PROBIOPlus™ to maintain healthy gastrointestinal microbiome during antibiotic treatment.

Gut Microbiota-Mediated Pharmacokinetic Drug-Drug Interactions between Mycophenolic Acid and Trimethoprim-Sulfamethoxazole in Humans

Mycophenolic acid (MPA) and trimethoprim-sulfamethoxazole (TMP-SMX) are commonly prescribed together in certain groups of patients, including solid organ transplant recipients. However, little is known about the pharmacokinetic drug-drug interactions (DDIs) between these two medications. Therefore, the present study aimed to determine the effects of TMP-SMX on MPA pharmacokinetics in humans and to find out the relationship between MPA pharmacokinetics and gut microbiota alteration. This study enrolled 16 healthy volunteers to take a single oral dose of 1000 mg mycophenolate mofetil (MMF), a prodrug of MPA, administered without and with concurrent use of TMP-SMX (320/1600 mg/day) for five days. The pharmacokinetic parameters of MPA and its glucuronide (MPAG) were measured using high-performance liquid chromatography. The composition of gut microbiota in stool samples was profiled using a 16S rRNA metagenomic sequencing technique during pre- and post-TMP-SMX treatment. Relative abundance, bacterial co-occurrence networks, and correlations between bacterial abundance and pharmacokinetic parameters were investigated. The results showed a significant decrease in systemic MPA exposure when TMP-SMX was coadministered with MMF. Analysis of the gut microbiome revealed altered relative abundance of two enriched genera, namely the genus Bacteroides and Faecalibacterium, following TMP-SMX treatment. The relative abundance of the genera Bacteroides, [Eubacterium] coprostanoligenes group, [Eubacterium] eligens group, and Ruminococcus appeared to be significantly correlated with systemic MPA exposure. Coadministration of TMP-SMX with MMF resulted in a reduction in systemic MPA exposure. The pharmacokinetic DDIs between these two drugs were attributed to the effect of TMP-SMX, a broad-spectrum antibiotic, on gut microbiota-mediated MPA metabolism.

Perspectives on Non-Prescription Antibiotic Use among Hispanic Patients in the Houston Metroplex

BACKGROUND

Non-prescription antibiotic use includes taking an antibiotic without medical guidance (e.g., leftovers, from friends/relatives, or purchased without a prescription). Non-prescription use contributes to antimicrobial resistance, adverse drug reactions, interactions, superinfection, and microbiome imbalance. Qualitative studies exploring perspectives regarding non-prescription use among Hispanic patients are lacking. We used the Kilbourne Framework for Advancing Health Disparities Research to identify factors influencing patients' non-prescription use and organize our findings.

METHODS

Our study includes Hispanic primary care clinic patients with different types of health insurance coverage in the Houston metroplex who endorsed non-prescription use in a previous survey. Semistructured interviews explored the factors promoting non-prescription use in Hispanic adults. Interviews were conducted remotely, in English or Spanish, between May 2020 and October 2021. Inductive coding and thematic analysis identified motives for non-prescription use.

RESULTS

Participants (n = 35) were primarily female (68.6%) and aged 27 to 66. Participants reported obtaining antibiotics through trusted persons, sold under-the-counter in US markets, and purchased without a prescription abroad. Factors contributing to non-prescription use included beliefs that the doctor visit was unnecessary, limited access to healthcare (due to insurance constraints, costs, and clinic wait times), and communication difficulties (e.g., language barriers with clinicians and perceived staff rudeness). Participants expressed confidence in medical recommendations from pharmacists and trusted community members.

CONCLUSIONS

Patient, healthcare system, and clinical encounter factors contribute to non-prescription use in Hispanic communities. Antibiotic stewardship interventions that involve pharmacists and trusted persons, improve access to care, and address communication barriers and cultural competency in the clinic may help reduce non-prescription use in these communities.

Land use as a critical determinant of faecal and antimicrobial resistance gene pollution in riverine systems

The WHO recognises antimicrobial resistance (AMR) as a global health threat. The environment can act as a reservoir, facilitating the exchange and the physical movement of resistance. Aquatic environments are at particular risk of pollution, with large rivers subject to pollution from nearby human, industrial or agricultural activities. The land uses associated with these activities can influence the type of pollution. One type of pollution and a likely contributor to AMR pollution that lowers water quality is faecal pollution. Both pose an acute health risk and could have implications for resistance circulating in communities. The effects of land use are typically studied using physiochemical parameters or in isolation of one another. However, this study aimed to investigate the impact of different land uses on riverine systems. We explored whether differences in sources of faecal contamination are reflected in AMR gene concentrations across agricultural and urban areas. Water quality from three rivers impacted by different land uses was assessed over one year by quantifying faecal indicator bacteria (FIB), microbial source tracking markers (MST) and AMR genes. In addition, a multiparametric analysis of AMR gene pollution was carried out to understand whether agricultural and urban areas are similarly impacted. Faecal indicators varied greatly, with the highest levels of FIB and the human MST marker observed in urban regions. In addition, these faecal markers correlated with AMR genes. Similarly, significant correlations between the ruminant MST marker and AMR gene levels in agriculture areas were observed. Overall, applying multiparametric analyses to include AMR gene levels, separation and clustering of sites were seen based on land use characterisation. This study suggests that differences in prescription of antimicrobials used in animal and human healthcare may influence environmental resistomes across agricultural and urban areas. In addition, public health risks due to exposure to faecal contamination and AMR genes are highlighted.

Exploring Pharmacological Treatments for Chronic Idiopathic Constipation in Adults: A Look Back to the Future

Despite great progress in pharmaceutical research, the medical treatment of chronic idiopathic constipation is far from ideal. The aim of the present article was to review literature data, focusing on poorly studied or commercially unavailable/unapproved drugs potentially useful for the treatment of chronic idiopathic constipation in adults. An extensive online literature search was conducted using the keywords "chronic constipation", "colon", "constipation", "drugs", "laxatives", and "treatment", in various combinations between January 1960 and December 2022. The literature search showed the presence of some drugs whose efficacy has only recently been demonstrated by modern investigations, and which are likely to be incorporated into future guidelines, of others that are proven effective and potentially effective on constipated patients but limited by small or relatively old studies, or by side effects which could be used in experienced hands, and of others that might be useful but lack a solid scientific background. Looking into the future for patients with chronic constipation might add some more tools to the therapeutic portfolio, especially for certain subgroups of these patients.

Flow-Based Fmoc-SPPS Preparation and SAR Study of Cathelicidin-PY Reveals Selective Antimicrobial Activity

Antimicrobial peptides (AMPs) hold promise as novel therapeutics in the fight against multi-drug-resistant pathogens. Cathelicidin-PY (NH₂-RKCNFLCKLKEKLRTVITSHIDKVLRPQG-COOH) is a 29-residue disulfide-cyclised antimicrobial peptide secreted as an innate host defence mechanism by the frog Paa yunnanensis (PY) and reported to possess broad-spectrum antibacterial and antifungal properties, exhibiting low cytotoxic and low hemolytic activity. Herein, we detail the total synthesis of cathelicidin-PY using an entirely on-resin synthesis, including assembly of the linear sequence by rapid flow Fmoc-SPPS and iodine-mediated disulfide bridge formation. By optimising a synthetic strategy to prepare cathelicidin-PY, this strategy was subsequently adapted to prepare a bicyclic head-to-tail cyclised derivative of cathelicidin-PY. The structure-activity relationship (SAR) of cathelicidin-PY with respect to the N-terminally positioned disulfide was further probed by preparing an alanine-substituted linear analogue and a series of lactam-bridged peptidomimetics implementing side chain to side chain cyclisation. The analogues were investigated for antimicrobial activity, secondary structure by circular dichroism (CD), and stability in human serum. Surprisingly, the disulfide bridge emerged as non-essential to antimicrobial activity and secondary structure but was amenable to synthetic modification. Furthermore, the synthetic AMP and multiple analogues demonstrated selective activity towards Gram-negative pathogen E. coli in physiologically relevant concentrations of divalent cations.

Effect of Clindamycin on Intestinal Microbiome and Miltefosine Pharmacology in Hamsters Infected with Leishmania infantum

Visceral leishmaniasis (VL), a vector-borne parasitic disease caused by Leishmania donovani and L. infantum (Kinetoplastida), affects humans and dogs, being fatal unless treated. Miltefosine (MIL) is the only oral medication for VL and is considered a first choice drug when resistance to antimonials is present. Comorbidity and comedication are common in many affected patients but the relationship between microbiome composition, drugs administered and their pharmacology is still unknown. To explore the effect of clindamycin on the intestinal microbiome and the availability and distribution of MIL in target organs, Syrian hamsters (120-140 g) were inoculated with L. infantum (108 promastigotes/animal). Infection was maintained for 16 weeks, and the animals were treated with MIL (7 days, 5 mg/kg/day), clindamycin (1 mg/kg, single dose) + MIL (7 days, 5 mg/kg/day) or kept untreated. Infection was monitored by ELISA and fecal samples (16 wpi, 18 wpi, end point) were analyzed to determine the 16S metagenomic composition (OTUs) of the microbiome. MIL levels were determined by LC-MS/MS in plasma (24 h after the last treatment; end point) and target organs (spleen, liver) (end point). MIL did not significantly affect the composition of intestinal microbiome, but clindamycin provoked a transient albeit significant modification of the relative abundance of 45% of the genera, including Ruminococcaceae UCG-014, Ruminococcus 2; Bacteroides and (Eubacterium) ruminantium group, besides its effect on less abundant phyla and families. Intestinal dysbiosis in the antibiotic-treated animals was associated with significantly lower levels of MIL in plasma, though not in target organs at the end of the experiment. No clear relationship between microbiome composition (OTUs) and pharmacological parameters was found.

The gut microbiota pathway mechanisms of diabetes

The contribution of dysbiotic gut microbiota configuration is essential when making reference to the metabolic disorders by increasing energy. It is important to understand that the gut microbiota induced metabolic disease mechanisms and inflammations. Thus it is imperative to have an insight into the state of all chronic subclinical inflammations influencing disease outcomes. However, from the emerging studies, there still exist inconsistencies in the findings of such studies. While making the best out of the reasons for inconsistencies of the findings, this review is designed to make a clear spell out as to the inconsistence of gut microbiota with respect to diabetes. It considered gut-virome alterations and diabetes and gut-bacteriome-gut-virome-alterations and diabetes as confounding factors. The review further explained some study design strategies that will spontaneously eliminate any potential confounding factors to lead to a more evidence based diabetic-gut microbiota medicine. Lipopolysaccharide (LPS) pro-inflammatory, metabolic endotoxemia and diet/gut microbiota insulin-resistance and low-grade systemic inflammation induced by gut microbiota can trigger pro-inflammatory cytokines in insulin-resistance, consequently, leading to the diabetic condition. While diet influences the gut microbiota, the consequences are mainly the constant high levels of pro-inflammatory cytokines in the circulatory system. Of recent, dietary natural products have been shown to be anti-diabetic. The effects of resveratrol on the gut showed an improved lipid profile, anti-inflammatory properties and ameliorated the endotoxemia, tight junction and glucose intolerance.

Urbanisation and its Associated Factors Affecting Human Gut Microbiota: Where are we Heading to?

ContextThe continuous rise in urbanisation and its associated factors have been reflected in the structure of the human gut ecosystem.ObjectiveThe main focus of the review is to discuss and summarise the major risk factors associated with urbanisation that affects human gut microbiota thus affecting human health.MethodsMultiple medical literature databases, namely PubMed, Google, Google Scholar, and Web of Science were used to find relevant materials for urbanization and its major factors affecting human gut microbiota/microbiome. Both layman and Medical Subject Headings (MeSH) terms were used in the search. Due to the scarcity of the data, no limitation was set on the publication date. Relevant material in the English language which includes case reports, chapters of books, journal articles, online news reports and medical records was included in this review.ResultsBased on the data discussed in the review, it is quite clear that urbanisation and its associated factors have long-standing effects on the human gut microbiota that result in alterations of gut microbial diversity and composition. This is a matter of serious concern as chronic inflammatory diseases are on the rise in urbanised societies.ConclusionA better understanding of the factors associated with urbanisation will help us to identify and implement new biological and social approaches to prevent and treat diseases and improve health globally by deepening our understanding of these relationships and increasing studies across urbanisation gradients.HIGHLIGHTSHuman gut microbiota has been linked to almost every important function, including metabolism, intestinal homeostasis, immune system, biosynthesis of vitamins, brain processes, and its behaviour.However, dysbiosis i.e., alteration in the composition and diversity of gut microbiota is associated with the pathogenesis of many chronic conditions.In the 21st century, urbanisation represents a major demographic shift in developed and developing countries.During this period of urbanisation, humans have been exposed to many environmental exposures, all of which have led to the dysbiosis of human gut microbiota.The main focus of the review is to discuss and summarize the major risk factors associated with urbanisation and how it affects the diversity and composition of gut microbiota which ultimately affects human health.

Effect of antibiotics and low-crude protein diets on growth performance, health, immune response, and fecal microbiota of growing pigs

This study aimed to investigate the effects of diets with and without antibiotics supplementation and diets with 18.5% and 13.0% crude protein (CP) on growth performance, carcass characteristics, disease incidence, fecal microbiota, immune response, and antioxidant capacity of growing pigs. One hundred and eighty pigs (59-day-old; 18.5 ± 2.5 kg) were distributed in a randomized complete block design in a 2 × 2 factorial arrangement, nine replicates, and five pigs per pen. The factors were CP (18.5% or 13.0%) and antibiotics (none or 100 mg/kg tiamulin + 506 mg/kg oxytetracycline). Medicated diets were fed from days 59 to 73. After that, all pigs were fed their respective CP diets from 73 to 87 days. Data were analyzed using the Mixed procedure in SAS version 9.4. From days 59 to 73, pigs fed antibiotics diets had higher (P < 0.05) average daily feed intake (ADFI), average daily weight gain (ADG), gain to feed ratio (G:F), compared to the diets without antibiotics. From days 73 to 87 (postmedicated period), any previous supplementation of antibiotics did not affect pig growth performance. Overall (days 59 to 87), pigs-fed antibiotics diets had higher (P < 0.05) G:F compared to pigs-fed diets without antibiotics. In all periods evaluated, pigs fed 18.5% CP diets had higher (P < 0.05) ADG and G:F compared to pigs fed 13.0% CP. Pigs fed the 13.0% CP diets had lower (P < 0.05) fecal score and diarrhea incidence than those fed 18.5% CP. Pigs fed 18.5% CP diets had improved (P < 0.05) loin area compared to pigs-fed diets with 13.0% CP. At 66 days of age, pigs-fed antibiotics diets had lower (P < 0.05) alpha diversity estimated with Shannon and Simpson compared to the pig-fed diets without antibiotics. At family level, pigs fed 18.5% CP diets had higher (P < 0.05) relative abundance of Streptococcaceae, and lower (P < 0.05) relative abundance of Clostridiaceae at days 66 and 87 compared with pigs fed 13.0% CP. Pigs-fed antibiotics diets had lower (P < 0.05) immunoglobulin G and protein carbonyl concentrations at day 66 compared to the pigs-fed diets without antibiotics. The reduction of dietary CP from 18.5% to 13.0% reduced the growth performance and loin muscle area of growing pigs, although it was effective to reduce diarrhea incidence. Antibiotics improved growth performance, lowered diarrhea incidence, improved components of the humoral immune response, and reduced microbiota diversity. However, in the postmedicated period, we found no residual effect on the general health of the animals, and considering the overall period, only G:F was improved by the use of antibiotics.

Immune mechanism of gut microbiota and its metabolites in the occurrence and development of cardiovascular diseases

The risk of cardiovascular disease (CVD) is associated with unusual changes in the human gut microbiota, most commonly coronary atherosclerotic heart disease, hypertension, and heart failure. Immune mechanisms maintain a dynamic balance between the gut microbiota and the host immune system. When one side changes and the balance is disrupted, different degrees of damage are inflicted on the host and a diseased state gradually develops over time. This review summarizes the immune mechanism of the gut microbiota and its metabolites in the occurrence of common CVDs, discusses the relationship between gut-heart axis dysfunction and the progression of CVD, and lists the currently effective methods of regulating the gut microbiota for the treatment of CVDs.

Long-term chemically protected sodium butyrate supplementation in broilers as an antibiotic alternative to dynamically modulate gut microbiota

Chemically protected sodium butyrate (CSB) is a new kind of sodium butyrate. Our previous study found that 1,000 mg/kg of CSB had the potential capacity of improving growth performance and promoting early development of small intestine in broilers. This study aimed to investigate the effect of long-term antibiotics or CSB supplementation for intestinal microflora dynamical regulation in broilers. One hundred ninety-two 1-day-old Arbor Acres male broilers were randomly allocated into 3 dietary treatment (8 replicates per treatment) and fed with a basal diet (CON), a diet supplemented with the antibiotics (enramycin, 8 mg/kg and aureomycin, 100 mg/kg) (ANT), or a diet supplemented with 1,000 mg/kg of CSB, respectively. Results showed that dietary supplementation of CSB or ANT treatment elevated the weight gain and feed conversion ratio (FCR; P < 0.05), as compared with control (CON) group. Additionally, CON, CSB, or ANT administration dynamically altered the gut microbiota composition as time goes on. The increased presence of potential pathogens, such as Romboutsia and Shuttleworthia, and decreased beneficial bacteria such as Alistipes, Akkermansia, and Bacteroides were verified in new gut homeostasis reshaped by long-term antibiotics treatment, which has adverse effects on intestinal development and health of broilers. Conversely, CSB supplementation could dynamically enhance the relative abundance of Bacteroides, and decrease Romboutsia and Shuttleworthia in new microflora, which has positive effects on intestinal bacteria of broilers compared with CON group. Meanwhile, CSB supplementation was significantly increased the concentration of propionic acid and total short chain fatty acids (total SCFA; P < 0.05) in comparison with CON and ANT groups. Moreover, CSB treatment significantly increased anti-inflammatory and antioxidative capacities (P < 0.05) of broilers compared with ANT group. Taken together, we revealed characteristic structural changes of gut microbiota throughout long-term CSB or ANT supplementation in broilers, which provided a basic data for evaluating the mechanism of action affecting intestinal health by CSB or ANT administration and CSB as an alternative to antibiotics in the broilers industry.

Antibiotic resistance in aquaculture and aquatic organisms: a review of current nanotechnology applications for sustainable management

Aquaculture has emerged as one of the world's fastest-growing food industries in recent years, helping food security and boosting global economic status. The indiscriminate disposal of untreated or improperly managed waste and effluents from different sources including production plants, food processing sectors, and healthcare sectors release various contaminants such as bioactive compounds and unmetabolized antibiotics, and antibiotic-resistant organisms into the environment. These emerging contaminants (ECs), especially antibiotics, have the potential to pollute the environment, particularly the aquatic ecosystem due to their widespread use in aquaculture, leading to various toxicological effects on aquatic organisms as well as long-term persistence in the environment. However, various forms of nanotechnology-based technologies are now being explored to assist other remediation technologies to boost productivity, efficiency, and sustainability. In this review, we critically highlighted several ecofriendly nanotechnological methods including nanodrug and vaccine delivery, nanoformulations, and nanosensor for their antimicrobial effects in aquaculture and aquatic organisms, potential public health risks associated with nanoparticles, and their mitigation measures for sustainable management.

Targeting gut microbiota to alleviate neuroinflammation in Alzheimer's disease

The gut microbiota came into focus within the last years regarding being associated with or even underlying neuropsychiatric diseases. The existence of the gut-brain-axis makes it highly plausible that bacterial metabolites or toxins that escape the intestinal environment or approach the vagal connections towards the brain, exert devastating effects on the central nervous system. In Alzheimer's disease (AD), growing evidence for dysbiotic changes in the gut microbiota is obtained, even though the question for cause or consequence remains open. Nevertheless, using modulation of microbiota to address inflammatory processes seems an attractive therapeutic approach as certain microbial products such as short chain fatty acids have been proven to exert beneficial cognitive effects. In this review, we summarize, contemporary knowledge on neuroinflammation and inflammatory processes within the brain and even more detailed in the gut in AD, try to conclude whom to target regarding human microbial commensals and report on current interventional trials.