ML241 Antagonizes ERK 1/2 Activation and Inhibits Rotavirus Proliferation

Rotavirus (RV) is the main pathogen that causes severe diarrhea in infants and children under 5 years of age. No specific antiviral therapies or licensed anti-rotavirus drugs are available. It is crucial to develop effective and low-toxicity anti-rotavirus small-molecule drugs that act on novel host targets. In this study, a new anti-rotavirus compound was selected by ELISA, and cell activity was detected from 453 small-molecule compounds. The anti-RV effects and underlying mechanisms of the screened compounds were explored. In vitro experimental results showed that the small-molecule compound ML241 has a good effect on inhibiting rotavirus proliferation and has low cytotoxicity during the virus adsorption, cell entry, and replication stages. In addition to its in vitro effects, ML241 also exerted anti-RV effects in a suckling mouse model. Transcriptome sequencing was performed after adding ML241 to cells infected with RV. The results showed that ML241 inhibited the phosphorylation of ERK1/2 in the MAPK signaling pathway, thereby inhibiting IκBα, activating the NF-κB signaling pathway, and playing an anti-RV role. These results provide an experimental basis for specific anti-RV small-molecule compounds or compound combinations, which is beneficial for the development of anti-RV drugs.

Impact of Limosilactobacillus fermentum probiotic treatment on gut microbiota composition in sahiwal calves with rotavirus diarrhea: A 16S metagenomic analysis study"

BACKGROUND

Diarrhea poses a major threat to bovine calves leading to mortality and economic losses. Among the causes of calf diarrhea, bovine rotavirus is a major etiological agent and may result in dysbiosis of gut microbiota. The current study was designed to investigate the effect of probiotic Limosilactobacillus fermentum (Accession No.OR504458) on the microbial composition of rotavirus-infected calves using 16S metagenomic analysis technique. Screening of rotavirus infection in calves below one month of age was done through clinical signs and Reverse Transcriptase PCR. The healthy calves (n = 10) were taken as control while the infected calves (n = 10) before treatment was designated as diarrheal group were treated with Probiotic for 5 days. All the calves were screened for the presence of rotavirus infection on each day and fecal scoring was done to assess the fecal consistency. Infected calves after treatment were designated as recovered group. Fecal samples from healthy, recovered and diarrheal (infected calves before sampling) were processed for DNA extraction while four samples from each group were processed for 16S metagenomic analysis using Illumina sequencing technique and analyzed via QIIME 2.

RESULTS

The results show that Firmicutes were more abundant in the healthy and recovered group than in the diarrheal group. At the same time Proteobacteria was higher in abundance in the diarrheal group. Order Oscillospirales dominated healthy and recovered calves and Enterobacterials dominated the diarrheal group. Alpha diversity indices show that diversity indices based on richness were higher in the healthy group and lower in the diarrheal group while a mixed pattern of clustering between diarrheal and recovered groups samples in PCA plots based on beta diversity indices was observed.

CONCLUSION

It is concluded that probiotic Limosilactobacillus Fermentum N-30 ameliorate the dysbiosis caused by rotavirus diarrhea and may be used to prevent diarrhea in pre-weaned calves after further exploration.

Aspirin inhibits rotavirus replication and alters rat gut microbial composition

BACKGROUND

Aspirin is widely used to treat various clinical symptoms. Evidence suggests that aspirin has antiviral properties, but little is known about its specific effect against rotavirus.

METHODS

MA104, Caco-2, and CV-1 cells were infected with rotavirus, and aspirin was added after 12 h. Viral mRNA and titer levels were measured by qRT-PCR and immunofluorescence assays. For in vivo validation, forty specific-pathogen-free SD rats were randomly divided into oral aspirin (ASP) groups and control (NC) groups. 16 S rRNA gene sequencing was performed to identify gut microbiota. After 6 months of continuous ASP/NC administration, the rats were infected with rotavirus. Fecal samples were collected over a 30-day time course, and viral levels were quantified. Proinflammatory cytokines/chemokine levels were measured by ELISA.

RESULTS

Aspirin inhibited rotavirus infection in cell lines and in rats. The effects of aspirin on viral replication were associated with the alteration of gut microbiota composition by aspirin, including increased abundance of Firmicutes and decreased abundance of Bacteroidetes after aspirin treatment. Mechanistically, aspirin reduced IL-2 and IL-10 levels, and increased IRF-1 and COX-2 levels. Aspirin blocked rotavirus replication in vitro and in vivo, which might be related to effects on IRF-1, COX-2, chemokines, and gut microbial composition.

CONCLUSION

These results indicate that long-term oral aspirin administration reduces rotavirus infection. Intestinal virus infection may be suppressed in elderly patients who take aspirin for a long time. The change of their Gut microbiota may lead to functional disorder of the intestinal tract, which may provide some reference for clinical adjuvant probiotics treatment.

Characterization of changes in the intestinal microbiome following combination therapy with zinc preparation and conventional treatment for children with rotavirus enteritis

Background

Rotavirus (RV) is one of the most common pathogens causing diarrhea in infants and young children worldwide. Routinely, antiviral therapy, intestinal mucosa protection, and fluid supplementation are used in clinic, however this is not efficacious in some severe cases. Zinc supplementation has previously been shown to improve resolution of symptoms from infectious diarrhea.

Methods

In this study differences in response rate, duration of hyperthermia, vomiting, and diarrhea, and the persistence time of cough and lung rales in groups were compared. 16SrDNA gene sequencing technology was used to analyze and compare changes in the intestinal microflora of children with RV enteritis who received the conventional treatment with or without the zinc preparation. In addition, the correlations between the differential bacterial species and the related inflammatory factors were determined.

Results

Conventional therapy combined with the zinc preparation significantly shortened the duration of hyperthermia, vomiting, and diarrhea compared with the conventional treatment alone. In addition, the time to symptom relief showed that the absorption time of cough and lung rales was significantly shorter in the combination treatment group than that in the conventional treatment group in the children with pneumonia. Further, compared with the conventional treatment, the combined treatment significantly increased the diversity and abundances of florae as compared with the conventional treatment. This combination therapy containing zinc preparation markedly increased the abundances of Faecalibacterium, Bacteroidales, Ruminoccoccoccus, and Lachnospiraceae at the genus level. The LEfSe analysis suggested that Clostridiumbolteae were most significantly altered after the combination therapy. In addition, a correlation analysis revealed significantly negative correlations between the inflammatory factors especially IL-6, TNF-a, CRP and some intestinal florae such as Bacteroides, Faecalibacterium, Blautia, Parabacteroides, Subdoligranulum, and Flavonifractor.

Conclusion

Compared with the conventional therapy alone, the combined therapy with the zinc preparation significantly improves symptoms caused by RV. The combination therapy containing the zinc preparation significantly increases the diversity and abundances of some beneficial groups of bacteria. Further, The presence of these groups was further negatively correlated with relevant inflammatory factors. More importantly, this combination therapy containing the zinc preparation provides a reference for the clinical management of children with RV enteritis.

Advances in the development of antivirals for rotavirus infection

Rotavirus (RV) causes 200,000 deaths per year and imposes a serious burden to public health and livestock farming worldwide. Currently, rehydration (oral and intravenous) remains the main strategy for the treatment of rotavirus gastroenteritis (RVGE), and no specific drugs are available. This review discusses the viral replication cycle in detail and outlines possible therapeutic approaches including immunotherapy, probiotic-assisted therapy, anti-enteric secretory drugs, Chinese medicine, and natural compounds. We present the latest advances in the field of rotavirus antivirals and highlights the potential use of Chinese medicine and natural compounds as therapeutic agents. This review provides an important reference for rotavirus prevention and treatment.

A Galactooligosaccharide Product Decreases the Rotavirus Infection in Suckling Rats

The leading cause of gastroenteritis among young children worldwide is the Group A rotaviruses (RV), which produce a wide range of symptoms, from a limited diarrhea to severe dehydration and even death. After an RV infection, immunity is not complete and less severe re-infections usually occur. These infections could be ameliorated by nutritional interventions with bioactive compounds, such as prebiotics. The aim of this research was to study the impact of a particular galactooligosaccharide (B-GOS) on the RV symptomatology and immune response during two consecutive infections. Lewis neonatal rats were inoculated with SA11 (first RV infection) on day 6 of life and with EDIM (second RV infection) on day 17 of life. B-GOS group was administered by oral gavage with a daily dose of B-GOS between days three to nine of life. Clinical and immunological variables were assessed during both infective processes. In the first infection, after the prebiotic intervention with B-GOS, a lower incidence, duration, and overall severity of the diarrhea (p < 0.05) was observed. In addition, it improved another severity indicator, the fecal weight output, during the diarrhea period (p < 0.05). The second RV infection failed in provoking diarrhea in the groups studied. The immune response during first infection with SA11 was not affected by B-GOS administration and had no impact on second infection, but the prebiotic intervention significantly increased IFN-γ and TNF-α intestinal production after the second infection (p < 0.05). In summary, B-GOS supplementation is able to reduce the incidence and severity of the RV-associated diarrhea and to influence the immune response against RV infections.

Efficacy of Probiotics in Treatment of Acute Rotavirus and Non Rotavirus Watery Diarrhoea in Children Admitted in Mymensingh Medical College Hospital

Probiotics are live microorganisms that, when administered in adequate amount helps in reducing the duration of diarrhoea. Objective of this double blind randomized controlled clinical trial was to assess the efficacy of probiotics in treatment of acute rotavirus & non rotavirus watery diarrhoea among children aged 6 months to 2 years admitted at diarrhoea corner of Paediatrics Department of Mymensingh Medical College Hospital from October 2017 to May 2019. It was a double blind randomized controlled clinical trial. Total 500 sample were divided into Group A=ORS, zinc plus placebo (n=250) and Group B=ORS, zinc plus probiotics (n=250). Both Group A and Group B consisted of children presented with rotavirus and non-rotavirus diarrhoea. Placebo or probiotics were given once daily for 5 days which was prepared and coded by department of Pharmacology. Stool specimens were taken to Microbiology Department of MMCH for rotavirus detection. Rotavirus was detected by Polyacrylamide gel electrophoresis (PAGE). Data was analyzed by computer using SPSS program version 23.0. A total of 500 children with acute watery diarrhoea were included. Among them 188 children were diagnosed as rotavirus positive. Among group A found 89 rotaviral and 161 non rotaviral diarrhoea patients. Among group B found 99 rotaviral and 151 non rotaviral diarrhoea patients. Baseline characteristics were similar in both groups. The duration of diarrhoea, hospital stay, and fever was significantly lesser in probiotics group when compared with control (p<0.001). But duration of vomiting did not reduce significantly in probiotics group. Frequency of stools reduced significantly in probiotics group.

18β-Glycyrrhetinic acid inhibits the apoptosis of cells infected with rotavirus SA11 via the Fas/FasL pathway

CONTEXT

18β-Glycyrrhetinic acid (18β-GA), a pentacyclic triterpenoid saponin metabolite of glycyrrhizin, exhibits several biological activities.

OBJECTIVE

We investigated the effects of 18β-GA on MA104 cells infected with rotavirus (RV) and its potential mechanism of action.

MATERIALS AND METHODS

Cell Counting Kit-8 was used to assess tissue culture infective dose 50 (TCID₅₀) and 50% cellular cytotoxicity (CC₅₀) concentration. MA104 cells infected with RV SA11 were treated with 18β-GA (1, 2, 4, and 8 μg/mL, respectively). Cytopathic effects were observed. The virus inhibition rate, concentration for 50% of maximal effect (EC₅₀), and selection index (SI) were calculated. Cell cycle, cell apoptosis, and mRNA and protein expression related to the Fas/FasL pathway were detected.

RESULTS

TCID₅₀ of RV SA11 was 10^-4.47/100 µL; the CC₅₀ of 18β-GA on MA104 cells was 86.92 µg/mL. 18β-GA showed significant antiviral activity; EC₅₀ was 3.14 μg/mL, and SI was 27.68. The ratio of MA104 cells infected with RV SA11 in the G0/G1 phase and the G2/M phase decreased and increased, respectively, after 18β-GA treatment. 18β-GA significantly induced apoptosis in the infected cells. Furthermore, after 18β-GA treatment, the mRNA and protein expression levels of Fas, FasL, caspase 3, and Bcl-2 decreased, whereas the expression levels of Bax increased.

DISCUSSION AND CONCLUSIONS

The study demonstrates that 18β-GA may be a promising candidate for the treatment of RV SA11 infection and provides theoretical support for the clinical development of glycyrrhizic acid compounds for the treatment of RV infection.

Gegen huangqin huanglian decoction for children rotavirus enteritis: A protocol for systematic review and meta-analysis

BACKGROUND

Rotavirus infection is the main cause of severe dehydration enteritis in children under 5 years old. It gives rise to malnutrition and even death in children even though there were rotavirus vaccines. However, there is no effective anti-virus drugs for rotavirus, supporting treatments are used in the clinics. Traditional Chinese medicine (TCM) has been treating diarrhea for many years. Gegen Huangqin Huanglian Decoction (GHHD)is a classic prescription for diarrhea in TCM. With the development of clinical trials and basic studies, GHHD has been proved that a good curative effect on diarrhea. Therefore, a systematic review is necessary to improve available evidence for GHHD in therapy of children under 5 years old with rotavirus enteritis.

METHODS

Different studies from various databases will be involved in this study. Only randomized controlled trials of rotavirus enteritis patients diagnosed with Guidelines for the Treatment of Acute Gastroenteritis in Outpatient Pediatrics, which released by the Washington International Children's Medical Center, Zhu Futang's Practical Pediatrics (7 th Edition), and the 2016 clinical practice guidelines for children with acute infectious diarrhea in China. We will search the literature in the databases from China Conference Paper Database, manual searching. Electronic database includes PubMed, Embase, Cochrane Library, Web of Science, CNKI (China National Knowledge Internet), WanFang, VIP (Chongqing VIP), and CBM (China Biomedical Literature CDROM Database). The primary outcomes include the total effective rate, the time of stopping diarrhea, the level of IL-6 serum concentration, fecal microflora ratio, the conversion of fecal rotavirus antigen. The secondary outcomes include clinical efficacy and the quantitative integral of TCM symptom, recovery time of stool character, treatment period. Besides, incidence of adverse events (such as irritation and toxicity) and costs will be also considered. Data will be extracted by 2 researchers independently, risk of bias of the meta-analysis will be evaluated based on the Cochrane Handbook for Systematic Reviews of Interventions. All data analysis will be conducted by data statistics software Review Manager V.5.3 and Stata V.12.0.

RESULTS

This study will synthesize and provide high-quality evidence based on the data of the currently published GHHD for the treatment of children rotavirus enteritis, in terms of the total effective rate, the time of stopping diarrhea, the level of IL-6 serum concentration, fecal microflora ratio, stool rotavirus antigen, clinical efficacy and the quantitative integral of TCM symptom, recovery time of stool character, treatment period, and safety.

CONCLUSION

This systematic review aims to evaluated the benefits and harms of GHHD for the treatment of children rotavirus enteritis reported in randomized controlled trials, and provide more options for clinicians and patients to treat children rotavirus enteritis.

REGISTRATION NUMBER

INPLASY2020100023.

IL-22-induced cell extrusion and IL-18-induced cell death prevent and cure rotavirus infection

Bacterial flagellin can elicit production of TLR5-mediated IL-22 and NLRC4-mediated IL-18 cytokines that act in concert to cure and prevent rotavirus (RV) infection. This study investigated the mechanism by which these cytokines act to impede RV. Although IL-18 and IL-22 induce each other's expression, we found that IL-18 and IL-22 both impeded RV independently of one another and did so by distinct mechanisms that involved activation of their cognate receptors in intestinal epithelial cells (IEC). IL-22 drove IEC proliferation and migration toward villus tips, which resulted in increased extrusion of highly differentiated IEC that serve as the site of RV replication. In contrast, IL-18 induced cell death of RV-infected IEC thus directly interrupting the RV replication cycle, resulting in spewing of incompetent virus into the intestinal lumen and causing a rapid drop in the number of RV-infected IEC. Together, these actions resulted in rapid and complete expulsion of RV, even in hosts with severely compromised immune systems. These results suggest that a cocktail of IL-18 and IL-22 might be a means of treating viral infections that preferentially target short-lived epithelial cells.

Antiviral activities of resveratrol against rotavirus in vitro and in vivo

BACKGROUND

Rotavirus (RV) is the primary causative agent for viral gastroenteritis among infants and young children worldwide. Currently, no clinically approved and effective antiviral drug for the treatment of RV infection is available.

PURPOSE

We investigated the potential anti-RV activity of resveratrol and underlying mechanisms by which resveratrol acted against RV.

METHODS

The anti-RV activity of resveratrol in vitro was evaluated using plaque reduction assays. The effects of resveratrol on yield of virion progeny, viral polyprotein expression and genomic RNA synthesis were respectively investigated using enzyme-linked immunosorbent assays, western blotting and qRT-PCR assays. Further, we also measured the antiviral effect of resveratrol by evaluation of antigen clearance and assessment of changes in proinflammatory cytokines/chemokines in RV-infected neonatal mouse model.

RESULTS

Our results indicated that 20 μM of resveratrol significantly inhibited RV replication in Caco-2 cell line by suppressing RV RNA synthesis, protein expression, viroplasm plaque formation, progeny virion production, and RV-induced cytopathy independent of the different strains and cell lines of RV that we used. Analysis of the effect of time post-addition of resveratrol indicated that its application inhibited early processes in the RV replication cycle. Further study of the underlying mechanism of anti-RV activity indicated that resveratrol inhibited RV replication by suppressing expression of heat-shock protein 90 (HSP90) mRNA and protein, and that the effect occurred in a dose-dependent manner. Overexpression of HSP90 was found to have attenuated the inhibitory effect of resveratrol on RV replication. Interestingly, the application of resveratrol were found to down-regulate the level of inhibition of RV-mediated MEK1/2 and ERK phosphorylation. Using a RV-infected suckling mice model, we found that application of resveratrol significantly lessened the severity of diarrhea, decreased viral titers, and relieved associated symptoms. Levels of mRNA expression of interleukin-2, interleukin-10, tumor necrosis factor-α, interferon-γ, macrophage inflammatory protein 1, and monocyte chemotactic protein-1 were all found to have been sharply reduced in intestinal tissue from mice which had been treated with resveratrol (10 or 20 mg/kg) after RV infection (p < 0.05).

CONCLUSION

These findings implied that resveratrol exhibits antiviral activity and could be a promising treatment for rotavirus infection.

Genipin inhibits rotavirus-induced diarrhea by suppressing viral replication and regulating inflammatory responses

Rotavirus is the leading cause of acute gastroenteritis among young children worldwide. However, agents specifically designed to treat rotavirus infection have not been developed yet. In this study, the anti-rotavirus and anti-inflammatory effects of genipin, a chemical compound found in the fruit of Gardenia jasminoides, were evaluated. Genipin had an antiviral effect against the human rotavirus Wa and SA-11 strains in vitro, and it inhibited two distinct stages of the viral replication cycle: attachment and penetration (early stage) in pre-treatment and assembly and release (late stage) in post-treatment. Additionally, genipin downregulated nitric oxide synthase and pro-inflammatory cytokines in lipopolysaccharide-stimulated RAW264.7 cells and rotavirus-infected Caco-2 cells. Oral administration of genipin before and after viral infection with the murine rotavirus epidemic diarrhea of infant mice strain led to a reduced duration of diarrhea and faecal viral shedding and to decreased destruction of the enteric epithelium. Genipin could have potential as a natural compound with preventive and therapeutic effects against infection and colitis caused by rotavirus.

A cost minimization analysis of &#945;2b-interferon supplementation in complex pharmacotherapy of rotavirus infection in newborns

Rotavirus is one of the most important causative agents of gastroenteritis in both infants and children worldwide, resulting in high mortality and morbidity, mainly in low-income, developing countries. Respective analysis of medical records of newborns hospitalized with acute gastroenteritis showed that the use of &#945;2b-interferon in complex pharmacotherapy was characterized by faster reverse development of clinical manifestations of the disease than in patients who did not receive interferon. In our study, we also aimed to estimate the effectiveness of &#945;2b-interferon supplementation in combination pharmacotherapy of newborns with suspected rotavirus infection. Achievement of this goal was possible with the construction of a decision tree model and determination of decision rules for inclusion of &#945;2b-interferon supplementation into the complex pharmacotherapy. The input parameters of the model were hospitalization days of patients stratified by such signs as the presence or absence of rotavirus infection, as well as the additional inclusion of &#945;2b-interferon supplementation in complex pharmacotherapy. The criterion for prediction and decision-making was global retrospective rotavirus prevalence. The feature of the simulation was that the costs were expressed as relative to each other, which allowed unifying the proposed methodology. Retrospective analysis of the clinical database of Ukrainian newborns with acute diarrhea has proved that the decision of &#945;2b-interferon supplementation as additional treatment could be cost-saving under 7.4 times its lower price.

Ursolic acid: A novel antiviral compound inhibiting rotavirus infection in vitro

Rotavirus is one of the leading causes of severe acute gastroenteritis in children under 5 years of age, mainly affecting developing countries. Once the disease is acquired, no specific treatment is available; as such, the development of new drugs for effective antirotaviral treatment is critical. Ursolic acid is a pentacyclic triterpenoid with antiviral activity, which has been studied extensively in vitro and in vivo. To study the potential antirotaviral activity of ursolic acid, its toxic potential for viral particles (virucidal effect) and cultured cells (cytotoxicity) was analysed. No effect on virion infectivity was observed with treatments of up to 40 µM ursolic acid, while incipient cytotoxicity started to be evident with 20 µM ursolic acid. The antiviral potential of ursolic acid was evaluated in in-vitro rotavirus infections, demonstrating that 10 µM ursolic acid inhibits rotavirus replication (observed by a decrease in viral titre and the level of the main viral proteins) and affects viral particle maturation (a process associated with the endoplasmic reticulum) 15 h post infection. Interestingly, ursolic acid was also found to hamper the early stages of the viral replication cycle, as a significant reduction in the number and size of viroplasms, consistent with a decrease in VP6 and NSP2 viral proteins, was observed 4 h post infection. As such, these observations demonstrate that ursolic acid exhibits antiviral activity, suggesting that this chemical could be used as a new treatment for rotavirus.

Oligosaccharides Modulate Rotavirus-Associated Dysbiosis and TLR Gene Expression in Neonatal Rats

Colonization of the gut in early life can be altered through multiple environmental factors. The present study aimed to investigate the effects of 2'-fucosyllactose (2'-FL), a mixture of short-chain galactooligosaccharides/long-chain fructooligosaccharides (scGOS/lcFOS) 9:1 and their combination (scGOS/lcFOS/2'-FL) on dysbiosis induced during rotavirus (RV) diarrhea in neonatal rats, elucidating crosstalk between bacteria and the immune system. The dietary interventions were administered daily by oral gavage at days 2-8 of life in neonatal Lewis rats. On day 5, RV SA11 was intragastrically delivered to induce infection and diarrhea assessment, microbiota composition, and gene expression of Toll-like receptors (TLRs) in the small intestine were studied. All dietary interventions showed reduction in clinical variables of RV-induced diarrhea. RV infection increased TLR2 expression, whereas 2'-FL boosted TLR5 and TLR7 expressions and scGOS/lcFOS increased that of TLR9. RV-infected rats displayed an intestinal dysbiosis that was effectively prevented by the dietary interventions, and consequently, their microbiota was more similar to microbiota of the noninfected groups. The preventive effect of 2'-FL, scGOS/lcFOS, and their combination on dysbiosis associated to RV diarrhea in rats could be due to changes in the crosstalk between gut microbiota and the innate immune system.

Clinical efficacy of oral immunoglobulin Y in infant rotavirus enteritis: Systematic review and meta-analysis

BACKGROUND

Rotavirus (RV) can cause vomiting and diarrhea in infants and children, and could be treated clinically with immunoglobulin Y (IgY), which is an immunoglobulin extracted from chicken yolk. There is no systematic evaluation of immunoglobulin in the treatment of rotavirus enteritis. Therefore, we systematically evaluated rotavirus enteritis with oral immunoglobulin Y therapy using meta-analysis.

METHODS

We conducted a systematic search in CNKI, WANFANG DATA, VIP, PubMed, and the Cochrane Library databases (up to April 30, 2018). Using Revman 5.3 software for meta-analysis.

RESULTS

A total of 2626 subjects with rotavirus diarrhea from 17 randomized clinical trials were included in the meta-analysis. Of these, 1347 subjects received oral immunoglobulin Y and 1279 subjects received conventional treatment. The results of the meta-analysis indicated that the total number of effective cases and effective rates of immunoglobulin Y in treatment of rotavirus enteritis in infants and children was statistically different from that in the control group (odds ratio [OR] = 3.87, 95% confidence interval [CI] (3.17, 4.74), P < .00001) and (OR = 3.63, 95% CI [2.75, 4.80], P < .00001).

CONCLUSIONS

Immunoglobulin Y is effective in the treatment of infantile rotavirus enteritis. Oral immunoglobulin Y can be widely used in the treatment of rotavirus enteritis in clinic.

Prevalence, risk factors and seasonal variations of different Enteropathogens in Lebanese hospitalized children with acute gastroenteritis

BACKGROUND

Acute gastroenteritis (AGE) is a major cause of pediatric morbidity and mortality around the world. It remains a frequent reason for infection-related admissions to emergency units among all age groups. Following the Syrian refugee crisis and insufficient clean water in our region, we sought to assess the etiological and epidemiological factors pertaining to AGE in South Lebanon.

METHODS

In this multi-center cross sectional clinical study, we analyzed the demographic, clinical and laboratory data of 619 Lebanese children from the age of 1 month to 5 years old who were admitted with AGE to pediatrics departments of three tertiary care centers in South Lebanon.

RESULTS

Our results revealed that males had a higher incidence of AGE (57.3%) than females. Enteropathogens were identified in 332/619 (53.6%) patients. Single pathogens were found in 294/619 (47.5%) patients, distributed as follows: Entamoeba histolytica in 172/619 (27.8%) patients, rotavirus in 84/619 (13.6%), and adenovirus in 38/619 (6.1%). Mixed co-pathogens were identified in 38/619 (6.1%) patients. Analyzing the clinical manifestations indicated that E. histolytica caused the most severe AGE. In addition, children who received rotavirus vaccine were significantly less prone to rotavirus infection.

CONCLUSIONS

Our findings alluded to the high prevalence of E. histolytica and other unidentified enteropathogens as major potential causes of pediatric AGE in hospitalized Lebanese children. This should drive us to widen our diagnostic panel by adopting new diagnostic techniques other than the routinely used ones (particularly specific for the pathogenic amoeba E. histolytica and for the unidentified enteropathogens), and to improve health services in this unfortunate area of the world where insanitary water supplies and lack of personal hygiene represent a major problem.

Targeting the Viral Polymerase of Diarrhea-Causing Viruses as a Strategy to Develop a Single Broad-Spectrum Antiviral Therapy

Viral gastroenteritis is an important cause of morbidity and mortality worldwide, being particularly severe for children under the age of five. The most common viral agents of gastroenteritis are noroviruses, rotaviruses, sapoviruses, astroviruses and adenoviruses, however, no specific antiviral treatment exists today against any of these pathogens. We here discuss the feasibility of developing a broad-spectrum antiviral treatment against these diarrhea-causing viruses. This review focuses on the viral polymerase as an antiviral target, as this is the most conserved viral protein among the diverse viral families to which these viruses belong to. We describe the functional and structural similarities of the different viral polymerases, the antiviral effect of reported polymerase inhibitors and highlight common features that might be exploited in an attempt of designing such pan-polymerase inhibitor.

Ondansetron treatment reduces rotavirus symptoms-A randomized double-blinded placebo-controlled trial

Background

Rotavirus and norovirus cause acute gastroenteritis with severe diarrhoea and vomiting, symptoms that may lead to severe dehydration and death. The objective of this randomized double-blinded placebo-controlled study was to investigate whether ondansetron, a serotonin receptor antagonist could attenuate rotavirus- and norovirus-induced vomiting and diarrhoea, which would facilitate oral rehydration and possibly accelerate recovery and reduce need for hospitalization.

Methods

Children with acute gastroenteritis, aged 6 months to 16 years where enrolled (n = 104) and randomized to one single oral dose (0.15mg/kg) of ondansetron (n = 52) or placebo (n = 52). The number of diarrhoea and vomiting episodes during the 24 hours following treatment was reported as well as the number of days with symptoms. Pathogens in faeces were diagnosed by real-time PCR. Outcome parameters were analyzed for rotavirus- and norovirus-positive children.

Results

One dose of oral ondansetron reduced duration of rotavirus clinical symptoms (p = 0.014), with a median of two days. Furthermore, ondansetron reduced diarrhea episodes, most pronounced in children that had been sick for more than 3 days before treatment (p = 0.028).

Conclusion

Ondansetron may be a beneficial treatment for children with rotavirus gastroenteritis.

Trial registration

European Clinical Trial Database EudraCT 2011-005700-15.

Immunomodulatory potential of β-glucan as supportive treatment in porcine rotavirus enteritis

A non-blinded randomized clinical trial was conducted to assess the immunomodulatory potential of β-glucan (BG) in piglet diarrhoea associated with type A rotavirus infection. A total of 12 rotavirus-infected diarrheic piglets were randomly divided into two groups: wherein six rotavirus-infected piglets were treated with supportive treatment (ST) and other six rotavirus-infected piglets were treated with BG along with ST (ST-BG). Simultaneously, six healthy piglets were also included in the study which served as control. In rotavirus-infected piglets, marked increase of Intestinal Fatty Acid Binding Protein-2 (I-FABP2), nitric oxide (NOx), Interferon-γ (IFN-γ) concentrations and decrease of immunoglobulin G (IgG) were noticed compared to healthy piglets. The faecal consistency and dehydration scores were significantly higher in rotavirus-infected piglets than healthy piglets. The ST-BG treatment progressively reduced the I-FABP2 and increased the IgG concentrations over the time in rotavirus-infected piglets compared to piglets received only ST. A pronounced enhancement of NOx and IFN-γ concentrations was observed initially on day 3 and thereafter the values reduced on day 5 in ST-BG treated piglets in comparison to piglets which received only ST. Additionally, ST-BG treatment significantly reduced faecal consistency and dehydration scores on day 3 compared to ST in rotavirus-infected piglets. These findings point that BG represents a potential additional therapeutic option to improve the health condition and reduce the piglet mortality from rotavirus associated diarrhoea where porcine rotavirus vaccine is not available.

IL-22 suppresses the infection of porcine enteric coronaviruses and rotavirus by activating STAT3 signal pathway

Interleukin-22 (IL-22), a member of the IL-10 superfamily, plays essential roles in fighting against mucosal microbial infection and maintaining mucosal barrier integrity within the intestine. However, little knowledge exists on the ability of porcine IL-22 (pIL-22) to fight against viral infection in the gut. In this study, we found that recombinant mature pIL-22 (mpIL-22) inhibited the infection of multiple diarrhea viruses, including alpha coronavirus, porcine epidemic diarrhea virus (PEDV), transmissible gastroenteritis virus (TGEV), and porcine rotavirus (PoRV), in the intestinal porcine epithelial cell line J2 (IPEC-J2) cells. mpIL-22 up-regulated the expression of the antimicrobial peptide beta-defensin (BD-2), cytokine IL-18 and IFN-λ. Furthermore, we found that mpIL-22 induced phosphorylation of STAT3 on Ser727 and Tyr705 in IPEC-J2 cells. Inhibition of STAT3 phosphorylation by S3I-201 abrogated the antiviral ability of mpIL-22 and the mpIL-22-induced expression of BD-2, IL-18, and IFN-λ. Together, mpIL-22 inhibited the infection of PoRV and enteric coronaviruses, and up-regulated the expression of antimicrobial genes in IPEC-J2, which were mediated by the activation of the STAT3 signal pathway. The significant antiviral activity of IL-22 to curtail multiple enteric diarrhea viruses in vitro suggests that pIL-22 could be a novel therapeutic against devastating viral diarrhea in piglets.

Effects of Racecadotril on Weight Loss and Diarrhea Due to Human Rotavirus in Neonatal Gnotobiotic Pigs (Sus scrofa domesticus)

Diarrheal disease is the second leading cause of death in children younger than 5 y, and the most common cause of acute watery diarrhea in young children worldwide is rotaviral infection. Medicines to specifically reduce diarrhea would be a desirable adjunctive treatment to supportive fluid therapy to decrease the mortality rate of diarrheal diseases. In this study, we evaluated the efficacy of an antisecretory drug, racecadotril, in treating human rotavirus (HRV)-induced diarrhea in a neonatal gnotobiotic pig model. In total, 27 gnotobiotic pigs were randomly assigned (n = 9 per group) to receive either racecadotril, chlorpromazine (positive-control drug), or PBS (mock treatment) after inoculation with HRV. Pigs were weighed daily and rectal swabs were collected to determine fecal consistency scores and virus shedding. Rotaviral infection was confirmed by ELISA and cell culture immunofluorescence. Overall, the racecadotril-treated pigs had less severe illness than either the chlorpromazine- or mock-treated groups; this conclusion was supported by the lower fecal-consistency scores, shorter duration of diarrhea, and significant gain in body weight during the course of the study of the racecadotril-treated pigs. Through its influence on decreasing intestinal hypersecretion, racecadotril was better able to control the clinical signs of rotaviral infection in the gnotobiotic pigs. These results lend support for using racecadotril as a treatment for rotaviral diarrhea.

Racecadotril in the Management of Rotavirus and Non-rotavirus Diarrhea in Under-five Children: Two Randomized, Double-blind, Placebo-controlled Trials

OBJECTIVE

To study the effect of racecadotril on reduction in the duration of acute rotavirus and non-rotavirus diarrhea.

DESIGN

Two randomized double-blind placebo-controlled trials.

SETTING

Community-based trial in an urban area in Vellore, hospital-based trial at a secondary hospital in Vellore.

PARTICIPANTS

199 and 130 3-59 month old children in the community- and hospital-based trials, respectively.

METHODS

Racecadotril (1.5 mg/kg/dose, thrice a day for three days) or placebo were given to manage acute diarrhea in both trials.

MAIN OUTCOME MEASURE

Median duration of diarrhea.

RESULTS

Among 124 children completing the hospital trial, the median duration of diarrhea was 25 h in both arms (P=0.5); median total stool weight was 74 g/kg and 53.5 g/kg in racecadotril group and placebo group, respectively (P=0.4); and average fluid intake per day was 3.6 mL/kg/h and 3mL/kg/h in racecadotril and placebo arms, respectively (P=0.3). Among rotavirus-positive children, median duration of diarrhea was 26.9 h and 30.2 h in racecadotril and placebo arms, respectively (P=0.7). In the community, 196 completed the trial, the median duration of diarrhea was 2 days for both arms (P=0.8) and rotavirus positive children had similar outcomes with median diarrheal duration of 3 d in both arms (P=0.4).

CONCLUSIONS

Treatment with racecadotril did not reduce diarrheal duration, stool volume or the requirement for fluid replacement in children with acute gastroenteritis, both with and without rotavirus infection.

Medicinal plants and natural molecules with in vitro and in vivo activity against rotavirus: A systematic review

BACKGROUND

Rotaviruses can cause life-threatening health disorders, such as severe dehydrating gastroenteritis and diarrhea in children. Vaccination is the main preventive strategy to reduce rotavirus diarrhea and the severity of episodes, but vaccines are not fully effective and new episodes may occur, even in vaccinated children. The WHO recommends oral rehydration therapy and zinc supplementation for rotavirus-induced diarrhea management. There is little preclinical evidence to support the use of phytotherapeutics in the management of rotaviral infections.

PURPOSE

We aim to review the use of medicinal plants and natural molecules in the management of rotavirus infections in experimental studies.

METHODS

Articles, published in the English language between 1991 and 2016, were retrieved from PubMed, Scopus and Web of Science using relevant keywords. The scientific literature mainly focusing on plant natural products with therapeutic efficacies against experimental models of rotavirus, were identified and tabulated. In addition, an assessment of the reliability of animal experiments was determined under ``Risk of Bias'' criteria.

CHAPTERS

After an initial search and a revision of the inclusion criteria, 41 reports satisfied the objectives of the study. 36 articles were found concerning the anti-rotaviral potential in rotavirus infected cell lines. Among the active secondary metabolites screened for rotavirus inhibition, the polyphenols of flavonoid structure had acquired the highest number of studies in our survey, compared to phenolic acids, stilbenoids, tannins, pectins, terpenoids and flavonoid glycosides. Also, many phytochemicals reduced the efficacy of viral capsid proteins foremost to their elimination and improved the tendency of host-cell inhibiting virus absorption or by prevention of viral replication. Furthermore, five in vivo studies reported that herbs, as well its components, reduced the duration and severity of diarrhea in mice and piglets. The anti-rotavirus efficacy were highlighted based on improvements in reduction on liquid stool, fecal virus shedding, small intestinal histology, levels of inflammation related cytokines and signaling receptors. However, the quality of the experiments in animal studies contained certain types of bias in terms of how they were conducted and reported.

CONCLUSION

We identified and summarized studies on medicinal plants and natural molecules having anti-rotavirus activity in order to further future developments of cures for rotavirus gastroenteritis.

Vitamin D3 supplementation alleviates rotavirus infection in pigs and IPEC-J2 cells via regulating the autophagy signaling pathway

Vitamin D had an anti-infection effect and benefited to the intestinal health. Autophagy signaling pathway was regulated by vitamin D3 to inhibit the infection of human immunodeficiency virus type-1. Rotavirus (RV) was a major cause of the severe diarrheal disease in young children and young animals. Although evidence suggested that vitamin D3 attenuates the negative effects of RV infection via the retinoic acid-inducible gene I signaling pathway, little is known of its antiviral effect whether through the regulation of autophagy. The present study was performed to investigate whether vitamin D3 alleviates RV infection in pig and porcine small intestinal epithelial cell line (IPEC-J2) models via regulating the autophagy signaling pathway. RV administration increased the Beclin 1 mRNA abundance in porcine jejunum and ileum. 5000 IU/kg dietary vitamin D3 supplementation greatly up-regulated LC3-II/LC3-I ratios and PR-39 mRNA expression under the condition of RV challenged. The viability of IPEC-J2 was significantly inhibited by RV infection. Incubation with 25-hydroxyvitamin D3 significantly decreased the concentrations of RV antigen and non-structural protein 4 (NSP4), and up-regulated the mRNA expression of Beclin 1 and PR-39 in the RV-infected IPEC-J2 cells. And then, based on the 25-hydroxyvitamin D3 treatment and RV infection, LC3-II mRNA expression in cells was inhibited by an autophagy inhibitor 3-methyladenine (3-MA). Bafilomycin A1 (Baf A1, a class of inhibitors of membrane ATPases, inhibits maturation of autophagic vacuoles) treatment numerically enhanced the LC3-II mRNA abundance, but had no effect on NSP4 concentration. Furthermore, 25-hydroxyvitamin D3 decreased the p62 mRNA expression and increased porcine cathelicidins (PMAP23, PG1-5 and PR-39) mRNA expression in the RV-infected cells. Taken together, these results indicated that vitamin D3 attenuates RV infection through regulating autophagic maturation and porcine cathelicidin genes expression.

Anti-VP6 VHH: An Experimental Treatment for Rotavirus A-Associated Disease

Species A Rotaviruses (RVA) remain a leading cause of mortality in children under 5 years of age. Current treatment options are limited. We assessed the efficacy of two VP6-specific llama-derived heavy chain antibody fragments (VHH) -2KD1 and 3B2- as an oral prophylactic and therapeutic treatment against RVA-induced diarrhea in a neonatal mouse model inoculated with virulent murine RVA (ECw, G16P[16]I7). Joint therapeutic administration of 2KD1+3B2 (200 μg/dose) successfully reduced diarrhea duration, RVA infection severity and virus shedding in feces. While the same dose of 2KD1 or 3B2 (200 μg) significantly reduced duration of RVA-induced diarrhea, 2KD1 was more effective in diminishing the severity of intestinal infection and RVA shedding in feces, perhaps because 2KD1 presented higher binding affinity for RVA particles than 3B2. Neither prophylactic nor therapeutic administration of the VHH interfered with the host's humoral immune response against RVA. When 2KD1 (200 μg) was administered after diarrhea development, it also significantly reduced RVA intestinal infection and fecal shedding. Host antibody responses against the oral VHH treatment were not detected, nor did viral escape mutants. Our findings show that oral administration of anti-VP6 VHH constitute, not only an effective prophylactic treatment against RVA-associated diarrhea, but also a safe therapeutic tool against RVA infection, even once diarrhea is present. Anti-VP6 VHH could be used complementary to ongoing vaccination, especially in populations that have shown lower immunization efficacy. These VHH could also be scaled-up to develop pediatric medication or functional food like infant milk formulas that might help treat RVA diarrhea.

[Therapeutic effects of zinc supplement as adjunctive therapy in infants and young children with rotavirus enteritis]

OBJECTIVE

To investigate the therapeutic effects of oral zinc supplement in infants and young children with rotavirus enteritis, and its preventive effects against diarrhea recurrence within 3 months after treatment.

METHODS

A total of 103 infants and young children with rotavirus enteritis were randomly divided into zinc supplement group (n=51) and conventional treatment group (n=52). Both groups were equally treated with a comprehensive therapy, besides which the zinc supplement group received zinc gluconate granules for 10 days. The treatment outcomes were examined at 72 hours after treatment, and the time required for the disappearance of positive symptoms and the recovery of injured extra-intestinal organs were determined. In addition, these patients were followed up for 3 months to determine the incidence of diarrhea recurrence after treatment.

RESULTS

The overall response rate in the zinc supplement group was significantly higher than that in the conventional treatment group (90% vs 75%; P<0.05). The durations of diarrhea, high fever, and vomiting in the zinc supplement group were significantly shorter than that in the conventional treatment group (P<0.05). In addition, the recurrence rate of diarrhea and the incidence of severe diarrhea within 3 months after treatment in the zinc supplement group were significantly lower than in the conventional treatment group (P<0.05).

CONCLUSIONS

Oral zinc supplement as adjunctive therapy is effective in treating infants and young children with rotavirus enteritis, and reducing the incidence and severity of diarrhea recurrence in the subsequent 3 months.

Anti-rotavirus effects by combination therapy of stevioside and Sophora flavescens extract

Anti-rotaviral activities of Sophora flavescens extract (SFE) and stevioside (SV) from Stevia rebaudiana Bertoni either singly or in various combinations were examined in vitro and in vivo using a porcine rotavirus G5[P7] strain. Combination of SFE and SV inhibited in vitro virus replication more efficiently than each single treatment. In the piglet model, SV had no effect on rotavirus enteritis, whereas SFE improved but did not completely cure rotaviral enteritis. Interestingly, combination therapy of SFE and SV alleviated diarrhea, and markedly improved small intestinal lesion score and fecal virus shedding. Acute toxicity tests including the piglet lethal dose 50, and body weight, organ weight and pathological changes for the combination therapy did not show any adverse effect on the piglets. These preliminary data suggest that the combination therapy of SV and SFE is a potential curative medication for rotaviral diarrhea in pigs. Determination of the efficacy of this combination therapy in other species including humans needs to be addressed in the future.

[Therapeutic effect of probiotics and oral IgY as supplementary drugs in the treatment of pediatric rotavirus enteritis: a comparative study]

OBJECTIVE

To compare the therapeutic effect of probiotics and oral immunoglobulin on pediatric rotavirus enteritis.

METHODS

A randomized, controlled trial was conducted in 150 children with rotavirus enteritis who were randomly divided into control, probiotic and immunoglobulin groups (n=50 each). In addition to basic treatment, the control group was given placebo, the probiotic group was given live combined bifidobacterium and lactobacillus tablets, and the immunoglobulin group was orally given anti-rotavirus egg yolk immunoglobulin (IgY). Clinical symptoms such as stool frequency and stool properties were recorded every day. Fresh stool samples were collected on days 1, 3, 5, 7, 9 and 11 of treatment. Intestinal flora imbalance was detected and divided into three degrees by microscopic examination of stool. Fecal SIgA level and fecal rotavirus shedding were measured by radioimmunoassay and double-antibody sandwich ELISA respectively.

RESULTS

Compared with the control group, the probiotic group had reduced intestinal flora imbalance, decreased stool frequency, and reduced incidence of secondary intestinal bacterial infection after 3 days of treatment (P<0.05). There was no significant difference in disease course between the probiotic and control groups. Compared with the control group, the immunoglobulin group had a significantly increased fecal SIgA level after 1 day of treatment (P<0.05), significantly decreased frequency of diarrhea and fecal rotavirus shedding after 3 days of treatment (P<0.05), and a significantly shorter disease course (4.5±1.0 vs 5.8±1.7 days; P<0.05).

CONCLUSIONS

For children with rotavirus enteritis, probiotics can reduce intestinal flora imbalance and prevent secondary intestinal bacterial infection, but probiotics take a long time to relieve clinical symptoms and cannot shorten the course of disease. Oral immunoglobulin takes effect quickly and can rapidly eliminate rotavirus, promote the production of SIgA, and shorten the course of disease.

Clinical Research Collaborative Group of ER XIE TING GRANULES. [A multicenter randomized parallel-controlled study on the efficacy and safety of er xie ting granules in children with acute diarrhea]

OBJECTIVE

To evaluate the efficacy and safety of ER XIE TING GRANULES in children with acute diarrhea.

METHOD

A multicenter, randomized, open-label, parallel-controlled clinical trial was carried out in 15 hospitals during March 2011 to July 2012. A total of 1489 children with acute diarrhea were enrolled and divided randomly into two groups and treated with ER XIE TING GRANULES (treatment group) and smectite powder (control group). The therapeutic efficacy and adverse drug reactions were evaluated after three-day and seven-day therapy.Superiority or non-inferiority test was done for effectiveness of the treatment based on efficacy differ by more than 10% regarded as the superiority.

RESULT

Totally 1458 children completed the study, in whom 726 children received ER XIE TING GRANULES and 732 received smectite powder. After three-day and seven-day therapy, cure rates and total efficacy rates of the treatment group were 44.2%, 94.1%, 88.8%, and 97.9% separately and higher than those of control group (39.3%, 88.4%, 83.9%, 97.4%) ( Z = 3.2, P < 0.01; Z = 2.46, P < 0.05). There were 520 children with rotavirus infection and in whom 266 cases received ER XIE TING GRANULES and 254 received smectite powder. For rotavirus enteritis, cure rates and total efficacy rates of the treatment group after three-day and seven-day therapy were 40.6%, 95.1%, 89.9%, and 98.9% separately and higher than those of control group (26.4%, 84.3%, 78.8%, and 96.8%) (Z = 4.807, P < 0.01;Z = 3.519, P < 0.01). The lower limits of the 95% confidence interval of difference of cure rate and total efficacy rates after three-day and seven-day therapy between two groups were less than 10%.No obvious drug related adverse reactions were found during the study.

CONCLUSION

ER XIE TING GRANULES has the same effect for treatment of acute diarrhea and rotavirus enteritis in children.No obvious drug related adverse reactions were found.

Recombinant monovalent llama-derived antibody fragments (VHH) to rotavirus VP6 protect neonatal gnotobiotic piglets against human rotavirus-induced diarrhea

Group A Rotavirus (RVA) is the leading cause of severe diarrhea in children. The aims of the present study were to determine the neutralizing activity of VP6-specific llama-derived single domain nanoantibodies (VHH nanoAbs) against different RVA strains in vitro and to evaluate the ability of G6P[1] VP6-specific llama-derived single domain nanoantibodies (VHH) to protect against human rotavirus in gnotobiotic (Gn) piglets experimentally inoculated with virulent Wa G1P[8] rotavirus. Supplementation of the daily milk diet with 3B2 VHH clone produced using a baculovirus vector expression system (final ELISA antibody -Ab- titer of 4096; virus neutralization -VN- titer of 256) for 9 days conferred full protection against rotavirus associated diarrhea and significantly reduced virus shedding. The administration of comparable levels of porcine IgG Abs only protected 4 out of 6 of the animals from human RVA diarrhea but significantly reduced virus shedding. In contrast, G6P[1]-VP6 rotavirus-specific IgY Abs purified from eggs of hyperimmunized hens failed to protect piglets against human RVA-induced diarrhea or virus shedding when administering similar quantities of Abs. The oral administration of VHH nanoAb neither interfered with the host's isotype profiles of the Ab secreting cell responses to rotavirus, nor induced detectable host Ab responses to the treatment in serum or intestinal contents. This study shows that the oral administration of rotavirus VP6-VHH nanoAb is a broadly reactive and effective treatment against rotavirus-induced diarrhea in neonatal pigs. Our findings highlight the potential value of a broad neutralizing VP6-specific VHH nanoAb as a treatment that can complement or be used as an alternative to the current strain-specific RVA vaccines. Nanobodies could also be scaled-up to develop pediatric medication or functional food like infant milk formulas that might help treat RVA diarrhea.

Group A rotavirus (RVA) is the most common cause of severe diarrhea in human infants worldwide. Live-attenuated rotavirus vaccines are available to prevent rotavirus diarrhea in children, although their efficacy in impoverished areas has been questioned, in addition to not being suitable for children suffering from immune deficiencies. Since no rotavirus-specific treatments are available as an alternative, we investigated llama-derived single-chain antibody fragments (VHH) as preventive therapy and a potential treatment option. Gnotobiotic piglets were chosen as an animal model because their gastrointestinal physiology and mucosal immune system resemble that of human infants. We evaluated the broad neutralizing activity of a VHH clone (3B2) to different genotypes of RVA circulating in humans, and tested the efficacy of oral administration of 3B2 VHH as a functional milk to prevent the diarrhea induced by one of the most prevalent human RVA strains (G1P[8]). Supplementation of the milk diet with 3B2 twice a day for 9 days conferred full protection against rotavirus-associated diarrhea and significantly reduced virus shedding in gnotobiotic piglets experimentally inoculated with a human RVA. This study demonstrates the potential application of VHH to prevent rotavirus-induced diarrhea, and suggests that VHHs should be further investigated as a suitable treatment for gastroenteritis.

[Application of immunospecific drug in the treatment of rotavirus gastroenteritis in children]

The case records of 120 children older than 4 years with rotavirus infection have been studied. In this group, 22 patients received basic therapy and 98 received complex therapy with cycloferon. Appropriate therapy resulted in rapid positive dynamics of clinical symptoms, the disease outcomes have been improved. Cytokine reaction has been studied as dependent on the treatment method. Positive dynamics of clinical symptoms and cytokine level has been revealed in a group of children having received cycloferon. It is recommended to include cycloferon in the basic therapy of rotavirus diarrhea in children.

Glycan-modifying bacteria-derived soluble factors from Bacteroides thetaiotaomicron and Lactobacillus casei inhibit rotavirus infection in human intestinal cells

Rotaviruses attach to intestinal cells in a process that requires glycan recognition. Some bacteria from the gut microflora have been shown to modify cell-surface glycans. In this study, human intestinal cultured cells were incubated with bacteria-derived soluble factors and infected with rotavirus. Results show that only bacterial soluble factors that increase cell-surface galactose namely, those of Bacteroides thetaiotaomicron and Lactobacillus casei were able to efficiently block rotavirus infections. Increasing cell-surface galactose using galactosyltransferase resulted in a similar blockage of rotavirus infections. These results indicate that manipulation of cell-surface intestinal glycans by bacterial soluble factors can prevent rotavirus infection in a species-specific manner, and should now be considered a potential therapeutic approach against rotavirus infection.

Rotavirus stimulates release of serotonin (5-HT) from human enterochromaffin cells and activates brain structures involved in nausea and vomiting

Rotavirus (RV) is the major cause of severe gastroenteritis in young children. A virus-encoded enterotoxin, NSP4 is proposed to play a major role in causing RV diarrhoea but how RV can induce emesis, a hallmark of the illness, remains unresolved. In this study we have addressed the hypothesis that RV-induced secretion of serotonin (5-hydroxytryptamine, 5-HT) by enterochromaffin (EC) cells plays a key role in the emetic reflex during RV infection resulting in activation of vagal afferent nerves connected to nucleus of the solitary tract (NTS) and area postrema in the brain stem, structures associated with nausea and vomiting. Our experiments revealed that RV can infect and replicate in human EC tumor cells ex vivo and in vitro and are localized to both EC cells and infected enterocytes in the close vicinity of EC cells in the jejunum of infected mice. Purified NSP4, but not purified virus particles, evoked release of 5-HT within 60 minutes and increased the intracellular Ca²⁺ concentration in a human midgut carcinoid EC cell line (GOT1) and ex vivo in human primary carcinoid EC cells concomitant with the release of 5-HT. Furthermore, NSP4 stimulated a modest production of inositol 1,4,5-triphosphate (IP₃), but not of cAMP. RV infection in mice induced Fos expression in the NTS, as seen in animals which vomit after administration of chemotherapeutic drugs. The demonstration that RV can stimulate EC cells leads us to propose that RV disease includes participation of 5-HT, EC cells, the enteric nervous system and activation of vagal afferent nerves to brain structures associated with nausea and vomiting. This hypothesis is supported by treating vomiting in children with acute gastroenteritis with 5-HT₃ receptor antagonists.

Rotavirus (RV) can cause severe dehydration and is a leading cause of childhood deaths worldwide. While most deaths occur due to excessive loss of fluids and electrolytes through vomiting and diarrhoea, the pathophysiological mechanisms that underlie this life-threatening disease remain to be clarified. Our previous studies revealed that drugs that inhibit the function of the enteric nervous system can reduce symptoms of RV disease in mice. In this study we have addressed the hypothesis that RV infection triggers the release of serotonin (5-hydroxytryptamine, 5-HT) from enterochromaffin (EC) cells in the intestine leading to activation of vagal afferent nerves connected to brain stem structures associated with vomiting. RV activated Fos expression in the nucleus of the solitary tract of CNS, the main target for incoming fibers from the vagal nerve. Both secreted and recombinant forms of the viral enterotoxin (NSP4), increased intracellular Ca²⁺ concentration and released 5-HT from EC cells. 5-HT induced diarrhoea in mice within 60 min, thereby supporting the role of 5-HT in RV disease. Our study provides novel insight into the complex interaction between RV, EC cells, 5-HT and nerves.

Characterization of in vivo anti-rotavirus activities of saponin extracts from Quillaja saponaria Molina

Rotavirus is the leading cause of severe diarrhea disease in newborns and young children worldwide with approximately 300,000 pre-adolescent deaths each year. Quillaja saponins are a natural aqueous extract obtained from the Chilean soapbark tree. The extract is approved for use in humans by the FDA for use in beverages as a food addictive. We have demonstrated that Quillaja extracts have strong antiviral activities in vitro against six different viruses. In this study, we evaluated the in vivo antiviral activity of these extracts against rhesus rotavirus (RRV) using a mouse model. We established that at a dosage of 0.015 mg/mouse of saponin extract, RRV induced diarrhea can be significantly reduced from 79% to 11% when mice are exposed to 500 plaque-forming-units (PFU) for each of five consecutive days. Additionally, while a reduction of RRV induced diarrhea depended both on the concentration of virus introduced and on the amount of Quillaja extract given to each mouse, the severity and interval of diarrhea under a variety of conditions tested, in all the treated mice were greatly reduced when compared to those that did not receive the Quillaja extracts. Mechanistically, there is strong evidence that the Quillaja extracts are able to "block" rotavirus infection by inhibiting virus-host attachment through disruption of cellular membrane proteins and/or virus receptors. We believe that Quillaja extracts have promise as antivirals to reduce rotavirus infection and the severity of the disease in humans.

Antiviral activity of Alpinia katsumadai extracts against rotaviruses

In vitro anti-rotavirus activity of Alpinia katsumadai (AK) extracts were evaluated against bovine G8P[7] and porcine G5P[7] rotaviruses in two different assay strategies, a mixed treatment assay and a post treatment assay. In the mixed treatment assay, six AK extracts [AK-1 (EtOH extract), AK-3 (H₂O layer), AK-5 (40% methanol fraction), and AK-9–11 (H₂O extract, polysaccharide fraction, supernatant fraction)] exhibited inhibitory activities against G5P[7] rotavirus with the EC₅₀ values ranging from 0.7 ± 0.4 to 33.7 ± 6.5 μg/mL. Extracts AK-1, AK-3, and AK-5 inhibited rotavirus infection against G8P[7] rotavirus, the with EC₅₀ values of 8.4 ± 2.2 μg/mL, 6.5 ± 0.8 μg/mL and 8.4 ± 5.0 μg/mL, respectively. By hemagglutination inhibition (HI) assay, six AK extracts completely inhibited viral adsorption onto human RBCs in both strains of rotaviruses at less than 11 μg/mL. However, in the post treatment assay, there was no anti activity shown against both strains of rotaviruses. As a result, six AK extracts were attributed mainly to having a strong interaction with hemagglutinin protein on the outer surface of rotavirus, resulting to blockage of viral adsorption.

[Clinical observation on treatment of infantile rotavirus enteritis by umbilical application of lunxieting paste]

OBJECTIVE

To observe the clinical effect of umbilical application with Lunxieting Paste (LXT) for the treatment of infantile rotavirus enteritis (IRE).

METHODS

One hundred and ninety infants with IRE were randomly assigned into three groups, 55 in Group A, 60 in Group B and 75 in Group C. All were treated with conventional therapy, mainly the dehydration and acidosis correcting, rehydration salt and antiviral therapy; but to patients in Groups B and C, an additional medication of Smecta 1.5 g, thrice a day. for infants below 1 year and 3 g, thrice a day. for those between 1-2 years old, by orally taken with 0.05 L of warm water and umbilical application with LXT (one dose per day, containing 6.0 g of crude drug) was given respectively.

RESULTS

The total effective rate was 69.1% in Group A, 75% in Group B and 92% in Group C, respectively, showing significant difference (P<0.05) in comparing Group C with Groups A and B. Moreover, serum levels of TNF-alpha were decreased and IFN-gamma increased in Group C after treatment, all showed statistical significance as compared with those in the other two groups (P<0.05). No significant adverse reactions were observed in all patients.

CONCLUSION

Umbilical application of LXT could effectively alleviate the diarrhea symptom in IRE patients, accelerate the negative inversion of rotavirus, and reduce the injury of intestinal membrane, showing a therapeutic efficacy more effective and quicker than that of conventional treatment with more convenience for use.

Effects of QWBZP on T-cell subsets and their cytokines in intestinal mucosa of HRV infection suckling mice

AIM OF THIS STUDY

Qiwei Baizhu Powder (QWBZP) is a traditional herbal prescription that has been used traditionally for the treatment of infantile diarrhea, including the infantile diarrhea caused by Human Rotavirus (HRV). In this study, we investigated the pharmacological activity of QWBZP extract.

MATERIALS AND METHODS

NIH suckling mice with HRV induced diarrhea were used. Density of CD3(+), CD4(+) and CD8(+) T cells, mRNA expression of IL-2, IFN-gamma, IL-4 and IL-10 in intestinal mucosa epithelial cells were assayed.

RESULTS

QWBZP extract promoted the expressions of mRNA of IL-2, IL-4, IL-10 and IFN-gamma in intestinal mucosa epithelial cells. Also, we found that the density of CD8(+) cells in intestinal mucosa epithelial cells was significantly lower in QWBZP group than in Model group, while the density of CD8(+) cells was significantly higher in QWBZP group than in Model group.

CONCLUSION

These data suggest that QWBZP extract may exhibit antiviral effects through modulating the densities of T-cell subsets and the expressions of their cytokines in small intestinal mucosa epithelial cells.

[Efficacy of Novalac AD in the treatment of infantile rotavirus enteritis]

OBJECTIVE

To observe clinical efficacy of Novalac AD in infantile rotavirus enteritis.

METHODS

20 infants with rotavirus enteritis but without dehydration and/or acidosis were selected to be fed by Novalac AD for one week.

RESULTS

Effective rate was 100%. All 20 subjects stool turned normal and systemic symptoms disappeared after treatment, with 17 within 48 h (85%,17/20) and 3 within 72 h (15%, 3/20).

CONCLUSION

Novalac AD has a significant effect on infantile rotavirus enteritis.

Randomized double blinded controlled trial to evaluate the efficacy and safety of Bifilac in patients with acute viral diarrhea

OBJECTIVE

To evaluate the efficacy and safety of Bifilac on reducing the episodes (frequency) and duration of diarrhea induced by rotaviral infection and to evaluate the efficacy of Bifilac to ameliorate the associated symptoms like dehydration and duration of rotaviral shedding in faeces.

METHODS

80 children aged between 3 months and 3 years were enrolled and divided into 2 groups, one group received standard therapy + placebo, the other group received standard therapy + probiotic (Bifilac) randomly. Children assessed for frequency and duration of diarrhea. Degree of dehydration, duration and volume of oral rehydration salt [ORS] therapy, duration and volume of Intra venous fluids and duration of rotaviral shedding.

RESULTS

When compared to the placebo, Bifilac showed clinical as well as statistically significant reduction in Number of episodes (frequency) of diarrhea in a day, mean duration of diarrhea (in days) degree of dehydration, duration and volume of oral rehydration salt [ORS] therapy, duration and volume of intravenous fluid [IVF] therapy, duration of rotaviral shedding (P<0.01).

CONCLUSION

The synbiotic, bifilac, appears to be a safe and very effective adjuvant in the management of acute rotaviral diarrhea.

Effect of a lactose-free milk formula supplemented with bifidobacteria and streptococci on the recovery from acute diarrhoea

Probiotics have been proposed for the management and prevention of acute diarrhoea in infants. A double-blind, randomised, placebo controlled study was carried out in 224 Chinese infants 6 to 36 months of age with severe acute diarrhoea and free from moderate or severe malnutrition. After oral or parenteral rehydration, they were allocated to one of three groups: a lactose-free formula (Control); the same formula but with viable 10(8)CFU B. lactis Bb12 and 5x10(7)CFU St. thermophilus TH4 per gram of powder and, the same formula with the same microorganisms, but with 10(9)CFU/g and 5x10(8)CFU, respectively. Anthropometric parameters, duration of the diarrhoea and rotavirus shedding were evaluated. Eighty seven percent of the episodes were associated with rotavirus infection. The duration of the diarrhoea was not influenced by the intake of probiotics. However, a decrease of rotavirus shedding was observed in infants fed the formula with 10(9) Bb12/g, a finding of probable epidemiological importance in the transmission of this agent.

Probiotics and zinc in acute infectious gastroenteritis in children: are they effective?

OBJECTIVE

Several studies in recent decades have assessed the effects of different probiotics in acute gastroenteritis, showing that specific strains of Lactobacilli (mainly Lactobacillus casei GG) and Saccharomyces boulardii may exert some beneficial therapeutic actions, mainly when used in rotavirus gastroenteritis, at a high dose, and in the early phase. The mechanisms of action of probiotics are not completely elucidated but seem to involve a complex interaction among epithelial, molecular, metabolic, and immune responses. Data on the prevention of community-acquired, nosocomial, and travelers' diarrhea are currently conflicting. Because each micro-organism has different properties, an accurate selection of the strain, dose, and patient should be cautiously considered.

METHODS AND RESULTS

Several reports from developing countries have demonstrated that supplements of zinc also provide significant reduction in stool output and duration, persistency, and severity of diarrhea. In view of the published data and of the different actions of zinc (such as improvement of the immune status, intestinal permeability, epithelial and enzymatic function, and electrolyte transport), the use of zinc as adjunctive therapy to oral rehydration solution has the potential to improve the management of diarrhea and decrease complications in children worldwide. In contrast to probiotics, which most trials in the developed world have used, there has been no trial with zinc performed in developed countries.

CONCLUSION

Data on the effect of a combined administration of zinc and probiotics in acute gastroenteritis are urgently needed.

Colonisation of the gastrointestinal tract by probiotic L. rhamnosus strains in acute diarrhoea in children

Lactobacillus rhamnosus (573L/1-3) strains are considered effective in the treatment of rotaviral diarrhoea in children. The colonisation of the gastrointestinal (G.I.) tract by the Lactobacillus rhamnosus strains and the determining factors are discussed reporting data of a prospective, double-blinded, placebo-controlled randomized study in children between the 2nd month and 6th year of life with acute diarrhoea lasting not longer than 5 days. The examined strains were detected in 37/46 (80.43%) patients after 5 days and in 19/46 (41.3%) patients after 14 days since the start of the treatment. L. rhamnosus 573L/1 strain colonised the G.I. tract more persistently. L. rhamnosus strains are effective in colonising the G.I. tract during acute diarrhoea. Persistence of colonisation is dependent on the properties of administered probiotic strains.