Clostridium sporogenes increases fat accumulation in mice by enhancing energy absorption and adipogenesis.

Gut bacteria belonging to the Clostridium family play a pivotal role in regulating host energy balance and metabolic homeostasis. As a commensal bacterium, Clostridium sporogenes has been implicated in modulating host energy homeostasis, albeit the underlying mechanism remains elusive. Therefore, this study aimed to investigate the impact of C. sporogenes supplementation on various physiological parameters, intestinal morphology, particularly adipose tissue accumulation, and glucolipid metabolism in mice. The findings reveal that mice supplemented with C. sporogenes for 6 weeks exhibited a notable increase in body weight, fat mass, adipocyte size, and serum triglyceride (TG) levels. Notably, the increased fat accumulation is observed despite consistent feed intake in treated mice. Mechanistically, C. sporogenes supplementation significantly improved the structure integrity of intestinal villi and enhanced energy absorption efficiency while reducing excretion of carbohydrates and fatty acids in feces. This was accompanied by upregulation of glucose and fatty acid transporter expression. Furthermore, supplementation with C. sporogenes promoted adipogenesis in both liver and adipose tissues, as evidenced by increased levels of hepatic pyruvate, acetyl-CoA, and TG, along with elevated expression levels of genes associated with lipid synthesis. Regarding the microbiological aspect, C. sporogenes supplementation correlated with an increased abundance of Clostridium genus bacteria and enhanced carbohydrate enzyme activity. In summary, C. sporogenes supplementation significantly promotes fat accumulation in mice by augmenting energy absorption and adipogenesis, possibly mediated by the expansion of Clostridium bacteria population with robust glycolipid metabolic ability. IMPORTANCE: The Clostridia clusters have been implicated in energy metabolism, the specific species and underlying mechanisms remain unclear. This present study is the first to report Clostridium sporogenes is able to affect fat accumulation and glycolipid metabolism. We indicated that gavage of C. sporogenes promoted the adipogenesis and fat accumulation in mice by not only increasing the abundance of Clostridium bacteria but by also enhancing the metabolic absorption of carbohydrates and fatty acids significantly. Obviously, changes of gut microbiota caused by the C. sporogenes, especially the significant increase of Clostridium bacteria, contributed to the fat accumulation of mice. In addition, the enhancement of Clostridium genus bacteria remarkably improved the synthesis of hepatic pyruvate, acetyl-CoA, and triglyceride levels, as well as reduced the excretion of fecal carbohydrates, short-chain fatty acids, and free fatty acids remarkably. These findings will help us to understand the relationship of specific bacteria and host energy homeostasis.

Validation of gavage sampling as tool for longitudinal sampling of microbiota of the mouse gastric lumen.

BACKGROUND: Fecal samples are commonly used for longitudinal studies of the gut lumen microbiome to track the course of response to infection or drug treatment, but no comparable method has been evaluated for longitudinal analysis of the gastric lumen microbiome in mice. Herein, a buffer flush of the stomach with a flexible gavage needle was used to collect gastric contents at one or several time points without harming the mouse. These samples were compared to samples collected by sacrifice and dissection of the mouse stomach. Microbiota from these samples were sequenced and evaluated in two ways: the composition of samples as measured by beta diversity and the richness of samples as measured by alpha diversity. Additionally, the effect of multiple sampling every two days on these metrics were studied. DNA was extracted from each of these samples and Illumina 16S rRNA gene sequencing was performed. RESULTS: First, taxonomic richness of gavage and dissection samples was compared. A greater number of taxa was detected in gavage samples than in dissection samples. Second, taxonomic richness was analyzed over time. No significant difference in taxonomic richness was observed with repeated gavage flushes. Third, a comparison was made of the taxonomic composition of samples collected by gavage versus dissection followed by a comparison of samples collected over multiple samplings. Nonmetric multidimensional scaling analysis revealed no clear differences between collection by gavage flushing or dissection. Using weighted Unifrac and Aitchison taxonomic distances between gavage and dissection samples were not significantly different from distances between gavage samples themselves, and no significant difference was found in the taxonomic composition of mice which were sampled repeatedly. Finally, relative abundances of specific identified taxa were compared, and eleven taxa were found to differ in frequency between collection methods. Using the more stringent Analysis of Composition of Microbiomes (ANCOM), seven was found to differ. Similarly, no significant differences were uncovered using these analyses over multiple samples by gastric flush. CONCLUSION: In summary, the consistency of the microbiota collected by gastric flushing recommends its use for microbiome analysis of gastric fluid similar to the use of fecal sampling to study the gut lumen microbiome.

Clinical efficacy of buprenorphine after oral dosing in rats undergoing major surgery.

Serum corticosterone, serum buprenorphine, body weight change, consumption of food and water and behaviour-based pain assessment were measured in catheterised and non-catheterised male Wistar rats undergoing myocardial infarct (MI) surgery under general anaesthesia following buprenorphine dosing by subcutaneous (Bup-SC, 0.05 mg/kg) and oral (Bup-O, 0.4 mg/kg) routes. Buprenorphine was dosed subcutaneously at half an hour before and 8, 16 and 24 hours after surgery (Bup-SC), orally at one hour before surgery (Bup-O1) or at one hour before and 12 hours after surgery (Bup-O2) in catheterised rats and at one hour before and 24 hours after surgery (Bup-O24) in non-catheterised rats. Serum corticosterone, body weight changes and food and water consumption were not significantly different between treatments in catheterised rats. Bup-SC resulted in rapidly decreasing serum concentrations below the clinically effective concentrations (1 ng/mL) already at two hours after the first dose. Bup-O provided significantly higher and slowly decreasing serum concentrations, at or above clinically effective concentrations, for 24 hours (Bup-O1) and 42 hours (Bup-O2) after surgery. In non-catheterised rats, body weight development and food consumption were significantly higher in Bup-O24 rats compared to Bup-SC rats. The results indicate that a SC buprenorphine dose of 0.05 mg/kg every eight hours provides long periods of serum concentrations below clinically effective levels, and that a higher dose and/or more frequent dosage are required to provide stable serum concentrations at or above clinically effective levels. A single oral buprenorphine dose of 0.4 mg/kg provides clinically effective and stable serum concentrations for 24 hours in rats after MI surgery.

Vanilla odor promotes oral feeding in premature infants-A randomized controlled trial.

PROPOSE: Introducing early oral feeding in premature infants is important because it supports intestinal maturation and helps prevent infections. In addition, early oral feeding is likely to contribute to improved neurocognitive outcomes in preterm infants. Several holistic therapeutic strategies have been developed to improve feeding skills, food tolerance, and the ability to drink independently, including practices such as early breastfeeding, oral stimulation, and subsequent olfactory stimulation. Based on several studies using olfactory stimulation with food odors (vanilla, breast milk) to promote oral feeding in preterm infants this study was conducted to test the following hypothesis: Does olfactory stimulation with vanilla or milk odor (breast milk or formula) lead to a reduction in the time required for nasogastric tube weaning in premature infants older than 26 + 6 weeks of gestational age? In addition, does it influence secondary outcomes such as length of hospital stay, weight development, and attainment of greater amounts of independently consumed food? METHODS: Premature with complete or partial feeding by gastric tube and without ventilation were included. For this study, 207 infants over 26 + 6 gestational weeks were randomized into three different study groups. Before each feeding, an olfactory presentation was made with milk odor, a vanilla Sniffin' Stick, or a control stick. In the final analysis, 165 infants were included (87 males, 78 females). At the time of randomization, infants were on average 12 ± 9.5 days old. RESULTS: While the influence of vanilla and milk odor did not provide a significant difference from the control for the primary outcome, a secondary analysis showed a significant group difference in the cumulative amount of independently drunk food consumed in the first ten days was the highest amount in the vanilla group. This time period was chosen due to the high dropout rate after the first ten days. In addition, there was a promising significance for earlier hospital discharge for prematurely below 32 weeks of gestation receiving vanilla odor stimulation in comparison to milk odor stimulation. CONCLUSION: Although the primary outcome of this study (gastric tube removal) did not provide significant results, a significant benefit of vanilla olfactory stimulation for preterm infants was demonstrated in subgroup analysis above milk odor stimulation. Younger preterm infants seem to benefit from the stimulation.

Acute Effects of Brevetoxin-3 Administered via Oral Gavage to Mice.

Brevetoxins (BTXs) constitute a family of lipid-soluble toxic cyclic polyethers mainly produced by Karenia brevis, which is the main vector for a foodborne syndrome known as neurotoxic shellfish poisoning (NSP) in humans. To prevent health risks associated with the consumption of contaminated shellfish in France, the French Agency for Food, Environmental and Occupational Health & Safety (ANSES) recommended assessing the effects of BTXs via an acute oral toxicity study in rodents. Here, we investigated the effect of a single oral administration in both male and female mice with several doses of BTX-3 (100 to 1,500 µg kg-1 bw) during a 48 h observation period in order to provide toxicity data to be used as a starting point for establishing an acute oral reference dose (ARfD). We monitored biological parameters and observed symptomatology, revealing different effects of this toxin depending on the sex. Females were more sensitive than males to the impact of BTX-3 at the lowest doses on weight loss. For both males and females, BTX-3 induced a rapid, transient and dose-dependent decrease in body temperature, and a transient dose-dependent reduced muscle activity. Males were more sensitive to BTX-3 than females with more frequent observations of failures in the grip test, convulsive jaw movements, and tremors. BTX-3's impacts on symptomatology were rapid, appearing during the 2 h after administration, and were transient, disappearing 24 h after administration. The highest dose of BTX-3 administered in this study, 1,500 µg kg-1 bw, was more toxic to males, leading to the euthanasia of three out of five males only 4 h after administration. BTX-3 had no effect on water intake, and affected neither the plasma chemistry parameters nor the organs' weight. We identified potential points of departure that could be used to establish an ARfD (decrease in body weight, body temperature, and muscle activity).

Micropipette-guided Drug Administration (MDA) as a non-invasive chronic oral administration method in male rats.

BACKGROUND: In preclinical studies resorting to rodents, the effects of prolonged oral intake of active substances are difficult to evaluate. Indeed, to get closer to clinical reality, oral gavage (OG) is frequently used but the repetition of administrations induces risks of lesions of the digestive tract, and stress for animals which can compromise the quality of the results. NEW METHOD: This study describes the development of a non-invasive oral administration method in male Sprague Dawley rats, as a safe alternative of OG, more faithful to clinical reality and limiting biases in pharmacokinetics and/or pharmacodynamics interpretation. Micropipette-guided Drug Administration (MDA) is based on the administration by micropipette of a sufficiently palatable vehicle for the animals to voluntarily take its contents. RESULTS: MDA was not demonstrated as less stressful than OG. A pharmacokinetics equivalence between MDA and OG was demonstrated for pregabalin administration but not for aripiprazole. Despite the use of a sweet vehicle, the MDA method does not result in weight gain or significant elevation of blood glucose and fructosamines level. Regarding the time needed to administrate the solution, the MDA method is significantly faster than OG. COMPARISON WITH EXISTING METHOD(S): Contrastingly to procedures using food or water, this method allows for a rigorous control of the time and dose administered and is delivered in discrete administration windows which is therefore closer to the clinical reality. This method appears particularly suitable for pharmacological evaluation of hydrophilic compounds. CONCLUSIONS: The MDA procedure represents a respectful and adapted pharmacological administration method to study the effects of chronic oral administration in rats.

Exacerbating effects of single-dose acute ethanol exposure on neuroinflammation and amelioration by GPR110 (ADGRF1) activation.

BACKGROUND: Neuroinflammation is a widely studied phenomenon underlying various neurodegenerative diseases. Earlier study demonstrated that pharmacological activation of GPR110 in both central and peripheral immune cells cooperatively ameliorates neuroinflammation caused by systemic lipopolysaccharide (LPS) administration. Ethanol consumption has been associated with exacerbation of neurodegenerative and systemic inflammatory conditions. The goal of this study is to determine the effects of single-dose acute ethanol exposure and GPR110 activation on the neuro-inflammation mechanisms. METHODS: For in vivo studies, GPR110 wild type (WT) and knockout (KO) mice at 10-12 weeks of age were given an oral gavage of ethanol (3 g/kg) or maltose (5.4 g/kg) at 1-4 h prior to the injection of LPS (1 mg/kg, i.p.) followed by the GPR110 ligand, synaptamide (5 mg/kg). After 2-24 h, brains were collected for the analysis of gene expression by RT-PCR or protein expression by western blotting and enzyme-linked immunosorbent assay (ELISA). Microglial activation was assessed by western blotting and immunohistochemistry. For in vitro studies, microglia and peritoneal macrophages were isolated from adult WT mice and treated with 25 mM ethanol for 4 h and then with LPS (100 ng/ml) followed by 10 nM synaptamide for 2 h for gene expression and 12 h for protein analysis. RESULTS: Single-dose exposure to ethanol by gavage before LPS injection upregulated pro-inflammatory cytokine expression in the brain and plasma. The LPS-induced Iba-1 expression in the brain was significantly higher after ethanol pretreatment in both WT and GPR110KO mice. GPR110 ligand decreased the mRNA and/or protein expression of these cytokines and Iba-1 in the WT but not in GPR110KO mice. In the isolated microglia and peritoneal macrophages, ethanol also exacerbated the LPS-induced expression of pro-inflammatory cytokines which was mitigated at least partially by synaptamide. The expression of an inflammasome marker NLRP3 upregulated by LPS was further elevated with prior exposure to ethanol, especially in the brains of GPR110KO mice. Both ethanol and LPS reduced adenylate cyclase 8 mRNA expression which was reversed by the activation of GPR110. PDE4B expression at both mRNA and protein level in the brain increased after ethanol and LPS treatment while synaptamide suppressed its expression in a GPR110-dependent manner. CONCLUSION: Single-dose ethanol exposure exacerbated LPS-induced inflammatory responses. The GPR110 ligand synaptamide ameliorated this effect of ethanol by counteracting on the cAMP system, the common target for synaptamide and ethanol, and by regulating NLRP3 inflammasome.

Case report: An adverse response to cyclosporin A treatment in BALB/cJ mice.

Cyclosporin A (CsA) is an immunosuppressive drug that has been widely used in mice at a range of doses from 10 to 200 mg/kg. Our group carried out an experiment in 2016 where we delivered 75 mg/kg CsA (NeoralTM) to BALB/cJ mice by oral gavage to enable wart formation in mice, which was moderately well-tolerated. We recently commenced another study using the same dose and route of delivery of CsA in BALB/cJ mice in order to immune suppress mice to make them susceptible for mouse papillomavirus infection. We highlight in this case report that in contrast to our earlier study, we observed almost immediate unexpected toxicity and had to terminate the recent experiment after only five days of treatment. Seven to eight-week-old female BALB/cJ mice were treated with 75 mg/kg of CsA by oral gavage daily for five days before treatment was stopped due to body weight loss and mice becoming moribund. The probability of survival of the mice following CsA treatment was 80% in this study, compared with 98% in our 2016 study. Mice showed signs of probable acute kidney injury, which was reversible following withdrawal of CsA. Although it is unclear why the clinical response to CsA in BALB/cJ mice differed markedly between the two experiments, this case report highlights the risk of CsA to mouse welfare. CD3 depletion has been used rather than CsA treatment in other studies and should be considered as an alternative to CsA treatment as it is immune-selective, and may be more effective at enabling wart formation in mice.

Can antibiotics for enteritis or for urinary tract infection disrupt the urinary microbiota in rats?

Background: To establish antibiotic preregimes and administration routes for studies on urinary microbiota. Methods and materials: Antibiotics for enteritis (Abx-enteritis) and UTIs (Abx-UTI) were administered via gavage and/or urinary catheterisation (UC) for 1 and/or 2 weeks. The effects of these Abx on the urinary microbiota of rats were examined via 16S rRNA sequencing and urine culture, including anaerobic and aerobic culture. Additionally, the safety of the Abx was examined. Results: Abx-enteritis/Abx-UTI (0.5 g/L and 1 g/L) administered via gavage did not alter the microbial community and bacterial diversity in the urine of rats (FDR > 0.05); however, Abx-UTI (1 g/L) administered via UC for 1 and 2 weeks altered the urinary microbial community (FDR < 0.05). Rats administered Abx-UTI (1 g/L) via UC for 1 week demonstrated a distinct urinary microbiota in culture. Abx-enteritis/Abx-UTI administered via gavage disrupted the microbial community and reduced bacterial diversity in the faeces of rats (FDR < 0.05), and Abx-UTI administered via UC for 2 weeks (FDR < 0.05) altered the fecal microbiota. Abx-UTI (1 g/L) administered via UC did not alter safety considerations. In addition, we noticed that UC did not induce infections and injuries to the bladder and kidney tissues. Conclusions: Administration of Abx-UTI via UC for 1 week can be considered a pre-treatment option while investigating the urinary microbiota.

Red osier dogwood extract versus Trimethoprim-sulfadiazine (Part 1). Effects on the growth performance, blood parameters, gut histomorphometry, and Salmonella excretion of broiler chickens orally challenged with Salmonella Enteritidis.

The poultry industry has not been spared from the prevalent incidence of diseases caused by invasive pathogens, especially Salmonella. Due to the pressing need to identify a suitable antibiotic alternative for use in poultry production, this study investigated the efficacy of red osier dogwood (ROD) extract on the growth, blood parameters, gut morphology, and Salmonella excretion in broiler chickens orally challenged with Salmonella Enteritidis (SE). A 4 × 2 factorial experiment was conducted based on 2 main factors, namely dietary treatments, and SE challenge. A total of 404, one-day-old male Ross broiler chicks were randomly assigned to 4 dietary treatments; 1) Negative control (NC), 2) NC + 0.075 ppm of Trimethoprim-sulfadiazine (TMP/SDZ)/kg of diet, 3) NC + 0.3% ROD extract, and 4) NC + 0.5% ROD extract. The absence of SE in the fecal samples obtained from chick delivery boxes was confirmed on d 0. On d 1, half of the birds were orally gavaged with 0.5 mL of phosphate-buffered saline each (noninfected group) and the remaining with 0.5 mL of 3.1 × 105 CFU/mL SE (infected group) in all treatment groups. Dietary treatments were randomly assigned to 8 replicate cages at 6 birds/cage. On 1-, 5-, 12-, and 18-day postinfection (DPI), cloacal fecal samples were collected on the 6 birds/cage to assess SE excretion. Average weight gain (AWG), average feed intake (AFI), feed conversion ratio (FCR), and mortality were determined weekly. On d 21, 10 chickens/treatment were euthanized to perform hematology, gut histomorphometry, serum immunoglobulins G and M (IgG and IgM), and superoxide dismutase measurements. Both ROD extract levels did not affect (P > 0.05) growth performance; however, the SE-infected birds showed increased (P < 0.05) AFI and FCR throughout the experimental period. Regardless of the SE-infection, both ROD extract levels improved (P < 0.05) duodenal villus height: crypt depth compared to other treatments. 0.5% ROD extract improved (P < 0.05) ileal villus width (VW) of noninfected birds and ileal crypt depth of infected birds, but it decreased (P < 0.05) the ileal VW of infected birds, compared to other treatments. The SE-infected birds showed lower (P < 0.05) lymphocytes (L) but increased (P < 0.05) heterophils (H), H:L, and monocytes (MON). Both ROD extract levels did not affect (P > 0.05) white blood cell differential, while dietary 0.3% ROD extract increased (P < 0.05) MON of the birds, regardless of infection model. Regardless of infection model, both TMP/SDZ and 0.5% ROD extract reduced the concentration of IgM in the serum, compared to the control and 0.3% ROD (P = 0.006). Conclusively, both ROD extract levels improved duodenal histomorphology and body defense against SE infection in broiler chickens; however, the 0.3% ROD extract was better.

Toxicity and Impact of Silica Nanoparticles on the Configuration of Gut Microbiota in Immunodeficient Mice.

Nanoparticles (NPs), having exceptional physicochemical and electrical characteristics with lower toxicity, have evolved as dynamic drug delivery carriers in living organisms. Potentially, the intragastric gavage of silica nanoparticles (SiNPs) affects gut microbiota profiles in immunodeficient mice. In this study, the impact of SiNPs of variable size and dosage was investigated in cyclophosphamide (Cy)-induced immunodeficient mice, specifically on their immune functions and gut microbiota, through physicochemical and metagenomic analysis. SiNPs of different sizes and doses were gavaged to Cy-induced immunodeficient mice for 12 days at an interval of 24 h to investigate their effects on immunological functions and the gut microbiome of mice. Our results showed that SiNPs had no significant toxicological effects on the cellular and hematological activities of immunodeficient mice. Furthermore, after the administration of different levels of SiNPs, no immune dysfunction was found in the immunosuppressed mice groups. However, gut-microbial studies and comparisons of characteristic bacterial diversity and compositions demonstrated that SiNPs significantly affect the abundance of different bacterial communities. LEfSe analysis revealed that SiNPs significantly increased the abundance of Lactobacillus, Sphingomonas, Sutterella, Akkermansia, and Prevotella, and potentially reduced Ruminococcus and Allobaculum. Thus, SiNPs significantly regulate and modify the configuration of the gut microbiota in immunodeficient mice. These dynamic variations in the intestinal bacterial community, abundance, and diversity provide new insight into the regulation and administration of silica-based NPs. This would be helpful for the further demonstration of the mechanism of action and prediction of the potential effects of SiNPs.

Leucine (and lysine) increased plasma levels of the satiety hormone cholecystokinin (CCK), and phenylalanine of the incretin glucagon-like peptide 1 (GLP-1) after oral gavages in pigs.

Excess dietary amino acids (AA) has been associated with reduced feed intake, increased satiation, and extended satiety in pigs. Recent ex vivo studies suggested that satiety peptide cholecystokinin (CCK) and insulinotropic glucagon-like peptide 1 (GLP-1), mediated the anorexigenic or insulinotropic effects of Lys, Glu, Phe, Ile, and Leu. However, the ex vivo model limitations require validation in vivo. The aim of the present study was to assess the effect of orally administered AA in vivo in pigs. It was hypothesized that oral Lys, Ile, and Leu have an anorexigenic effect via CCK, while Glu and Phe have an insulinotropic effect increasing circulating levels of GLP-1. Eight entire male pigs (Landrace × Large White) of 18.23 ±â€…1.06 kg of body weight were administered an oral gavage of water (control) or a 3 mmol/kg of Glu, Ile, Leu, Lys, Phe, or glucose (positive control for GLP-1 release) following an overnight fasting during 5 consecutive days using an incomplete latin square design. Blood samples were collected from the jugular vein before (-5 min, baseline value) and after the gavage (5, 15, 30, 60 and 90 min) to assess CCK and GLP-1 plasma levels. Pigs administered the oral gavage of Leu (P < 0.05), or Lys (P < 0.1) had increased levels of plasma CCK from 0 to 90 min post-gavage when compared to the control. A strong association (P < 0.001) was observed between GLP-1 plasma levels with Phe intake. The impact was significant starting 30 min post-gavage and was sustained until the end of the experiment (90 min post-gavage). Glucose administration increased GLP-1 early after the intake at the 5 min mark (P < 0.1). A positive correlation (P < 0.05, r = 0.89) driven by the impact of Phe at the 60 to 90 min post-gavage was identified between CCK and GLP-1 indicating feedback mechanisms between proximal and distal small intestine. In conclusion, oral gavages of Leu and Lys increased anorexigenic hormone CCK plasma levels in pigs. Phe caused a significant long-lasting increase in incretin GLP-1 plasma levels. Blood CCK and GLP-1 concentrations in Phe gavaged pigs were positively correlated indicating a potential feedback mechanism between proximal (CCK) and distal (GLP-1) small intestine. The present results are compatible with the known anorexigenic effects of excess dietary Leu and Lys, and the insulinotropic effect of Phe in pigs. These results demonstrate the relevance of accurate feed formulation practices particularly in post weaning pigs.

Previous ex vivo studies showed how the amino acids (AA) Lys, Leu, Ile, Phe, and Glu increased satiety peptide cholecystokinin (CCK) and/or insulinotropic hormone glucagon-like peptide 1 (GLP-1) model in pigs. The objective of this study was to validate the ex vivo model by testing the AA of interest in live pigs. Following the oral administration by gavage Leu increased plasma CCK compared to water. Phe showed a sustained long-lasting increase in GLP-1 plasma levels appearing 30 min after the gavage. A positive correlation between CCK and GLP-1 blood levels was observed for Phe treated pigs between 60 and 90 min after the treatment indicating that GLP-1 may induce the release of CCK in the small intestine via feedback mechanisms. The results also showed a trend for Lys increasing CCK congruent with previous data reporting an inhibition of appetite by dietary excess of this AA. These findings are relevant for commercial feeding practices since Lys is often supplemented and dietary Leu is commonly high in pig feeds. Finally, our results highlight the relevance of aromatic AA (i.e., Phe), in pig nutrition that deserves additional attention. There is significant room for improving the understanding of optimal AA levels in pig feeds.

Subchronic toxicity study of ferric oxide nanoparticles through intragastric administration: A 94-d, repeated dose study in Sprague Dawley rats.

In this study, the toxicity of ferric oxide nanoparticles (Fe2O3 NPs) administered through gavage to Sprague Dawley (SD) rats for 94 d, consecutively and the recovery after Fe2O3 NPs withdrawal for 30 d were evaluated. The vehicle control group, low-, medium-, and high-dose groups were administered with the vehicle (0.5% sodium carboxymethyl cellulose [CMC-Na]), 125, 250, and 500 mg/kg of Fe2O3 NPs, respectively, administered every morning for 94 d. There was no significant difference in the body weight, food intake, hematological, blood biochemical, and urine indices of SD rats in each administration group and the control group (P > 0.05). There was no significant difference in organ weight, organ indices, and the coefficient of the visceral brain between the SD rats in the different dosage groups and the SD rats in the vehicle control group (P > 0.05). Histopathological observations showed that there was no correlation between the pathological lesions of the organs observed in this study and the dose of Fe2O3 NPs (P > 0.05). The no-observed-adverse-effect level (NOAEL) dose of Fe2O3 NPs was initially determined to be 500 mg/kg administered to SD rats through oral gavage for 94 d, consecutively, followed by recovery after Fe2O3 NPs withdrawal for 30 d.

Comparing the Efficacy of a New Clinical Skills Model with a Traditional Method to Teach Tube Feeding of an Avian Patient.

Interactive clinical skills models have been demonstrated to be useful for teaching medical and veterinary clinical skills, yet to date, very few exist for teaching skills relevant to zoological companion animals and wildlife species including birds. This two-part study aimed to create, develop, and validate a model. Interviews and a survey were conducted using veterinary and wildlife professionals to select an avian clinical skill that is challenging and performed frequently. Tube/gavage feeding, or "crop tubing" satisfied both criteria; on average it was performed 71 times a year by surveyed respondents was rated 3.4/9 for difficulty of teaching and 3.5/9 for difficulty of learning. Therefore, a new model of a bird, made from a soft toy, silicone, and 3D printed parts, was designed to train students to perform this technique. Forty-two participants were recruited and divided into two groups; one used the model the other watched an instructional video on crop tubing. The students completed a self-evaluated confidence questionnaire, before and after, using either resource. They then performed the technique on a dead bird and their proficiency at 10 different actions that comprised the technique was evaluated by two assessors. The model group performed significantly better than the video group on all evaluated actions (U ≤ 143.5, p ≤ .0031), and reported significantly higher confidence (U = 129.5, p = 0.018). In conclusion, the newly developed model in combination with an instruction booklet offers an effective and inexpensive alternative way to teach crop tubing in a teaching environment, without compromising animal welfare.

Nifty Cup Versus Katori-Spoon Feeding in Preterm Infants: A Randomized Controlled Trial.

Background: Many preterm infants cannot breastfeed directly and depend on other feeding methods. Multiple studies have compared feeding methods for such infants; however, the best method remains unknown. We compared Nifty cup with Katori-spoon feeding in preterm neonates deemed fit for oral feeding. Methods: This open-label randomized controlled trial was performed in a level III neonatal unit. Preterm (<34 weeks) neonates deemed fit to initiate oral feeding were randomly allocated to the Nifty cup and Katori-spoon groups. Patients were followed up until 40 (±2) weeks of postmenstrual age or until death, whichever occurred earlier. The primary outcome was time to achieve full oral feeding. The secondary outcomes included the time spent per feeding session, time to full direct breastfeeding, anthropometry at discharge, duration of hospitalization, and mortality. The opinions of mothers and nurses were recorded using a structured questionnaire. Results: A total of 106 participants (53 in each group) were randomized and analyzed for the primary outcome. The median (1st, 3rd quartile) time to achieve complete oral feeds was 5 (2, 11) versus 6 (4, 11) days in the Nifty cup versus Katori-spoon groups, respectively (p = 0.2). Infants in the Nifty cup group reached full breastfeeds earlier (mean difference = 12.6 days; 95% confidence interval: 4.3 to 20.8, p = 0.003) and had less vomiting (9.4% versus 26.4%, p = 0.023). Mothers and nurses felt that breast milk expression and feeding with a Nifty cup was easier. Conclusions: Compared to the Katori-spoon, feeding with a Nifty cup did not shorten the time to full oral feeds. However, it helps in attaining full breastfeeds earlier than the Katori-spoon. Trial Registration: Clinical Trials Registry-India (CTRI/2021/06/034252).

Single-day and multi-day exposure to orogastric gavages does not affect intestinal barrier function in mice.

Animals involved in common laboratory procedures experience minor levels of stress. The direct effect of limited amounts of stress on gastrointestinal function has not been reported yet. Therefore, this study aimed to assess the effect of single-day and multi-day orogastric gavages on gut physiology in mice. To this end, 12-wk-old female C57Bl6/J mice were randomized to receive treatment with sterile water (200 µL) delivered by orogastric gavages twice daily for a total of 1 or 10 day(s). Control animals did not receive any treatment. Subsequently, gastrointestinal function was assessed by measuring fecal pellet production. Furthermore, ex vivo intestinal barrier and secretory function of the distal colon, proximal colon, and terminal ileum were quantified in Ussing chambers. In mice, single-day gavages did neither influence corticosterone levels nor gastrointestinal function. In mice exposed to multi-day gavages, corticosterone levels were slightly but significantly increased compared with controls after 10 days of treatment. Gastrointestinal motor function was altered, as evidenced by increased fecal pellet counts and a small increase in fecal water content. However, exposure to repeated gavages did not lead to detectable alterations in gastrointestinal barrier function as quantified by the paracellular flux of the probe 4 kDa FITC-dextran as well as transepithelial resistance measurements. Thus, the administration of drugs via single-day or multi-day orogastric gavages leads to no or minor stress in mice, respectively. In both cases, it does not hamper the study of the intestinal barrier function and therefore remains a valuable administration route in preclinical pharmacological research.NEW & NOTEWORTHY Exposure of mice to serial orogastric gavages over the course of 10 days leads to a small but significant increase in plasma corticosterone levels, indicating the presence of a limited amount of stress that is absent after a single-day treatment. This minor stress after multi-day gavages results in increased fecal pellet production and fecal water content in exposed compared with nontreated mice but does not affect the intestinal barrier function in the distal colon, proximal colon, or terminal ileum.

Effect of different ways of ingesting orange essential oil on blood immune index and intestinal microflora in mice.

BACKGROUND: Studies have found that the addition of plant essential oils to feed had a positive effect on intestinal microflora and immunity in mice. However, the effect of different ways of ingestion of orange essential oil on mice has seldom been reported. In the present study, we investigated the effects of ingestion of orange essential oil by gavage, sniffing and feeding on intestinal microflora and immunity in mice. RESULTS: The results obtained showed that a low concentration of essential oil feeding significantly increased the spleen index of mice (P < 0.05). The effect of different ways of ingestion on the thymus index, immunoglobulin G and immunoglobulin M of mice was not significant (P > 0.05). High and medium concentrations of essential oil feeding increased the level of interleukin-2 in mice (P < 0.05). H+ K+ -ATPase activity was significantly increased in mice fed with gavage and different concentrations of essential oil feed compared to the control group (P < 0.05). The analysis of the results of the microflora in the cecum and colon of mice indicated that the medium concentration of essential oil feeding group and the sniffing group significantly changed the structure of the flora and increased the diversity of the intestinal microflora. All three essential oil ingestion methods increased the abundance of Bacteroidetes and Lactobacillus in the intestine of mice. CONCLUSION: Compared with gavage and feeding, sniffing had a significant effect on immunoglobulins in mice. All the three ingestion methods could affect the intestinal microflora of mice and increase the abundance of Lactobacillus. © 2022 Society of Chemical Industry.

Distribution and toxicity of submicron plastic particles in mice.

Although microplastics (MPs) have become a global issue, the biodistribution and toxicities of MPs were still unclear. In this study, c57BL/6 mice were treated with submicron-sized MPs labeled with Nile red fluorescence by oral gavage three times a week for four consecutive weeks. Flow cytometry and microscopy technique were used to examine the concentration and distribution of MPs in various tissues and biofluids. The oxidative stress and inflammation were assessed via liquid chromatography-mass spectrometry and enzyme-linked immunosorbent assay, respectively. Submicron-sized MP signals were found in the intestines, liver, spleen, kidney, lungs, blood, and urine of mice after MP exposure. Increased oxidative stress in mouse urine and elevated inflammatory cytokines in mouse kidney were also recorded. In conclusion, flow cytometry is a useful tool for examining the number concentrations of MPs. Increased oxidative stress and inflammation after MP treatment indicates that the toxicity of MP warrants further investigation.

Transdermal Application of Soluble CuII(atsm) Increases Brain and Spinal Cord Uptake Compared to Gavage with an Insoluble Suspension.

CuII(atsm) is a blood-brain barrier permeant copper(II) compound that is under investigation in human clinical trials for the treatment of neurodegenerative diseases of the central nervous system (CNS). Imaging in humans by positron emission tomography shows the compound accumulates in affected regions of the CNS in patients. Most therapeutic studies to date have utilised oral administration of CuII(atsm) in an insoluble form, as either solid tablets or a liquid suspension. However, two pre-clinical studies have demonstrated disease-modifying outcomes following transdermal application of soluble CuII(atsm) prepared in dimethyl sulphoxide. Whether differences in the method of administration lead to different degrees of tissue accumulation of the compound has never been examined. Here, we compare the two methods of administration in wild-type mice by assessing changes in tissue concentrations of copper. Both administration methods resulted in elevated copper concentrations in numerous tissues, with the largest increases evident in the liver, brain and spinal cord. In all instances where treatment with CuII(atsm) resulted in elevated tissue copper, transdermal application of soluble CuII(atsm) led to higher concentrations of copper. In contrast to CuII(atsm), an equivalent dose of copper(II) chloride resulted in minimal changes to tissue copper concentrations, regardless of the administration method. Data presented herein provide quantitative insight to transdermal application of soluble CuII(atsm) as a potential alternative to oral administration of the compound in an insoluble formulation.

Pre-feeding premature infant oral motor intervention (PIOMI) for transition from gavage to oral feeding: A randomised controlled trial.

PURPOSE: To assess the performance of premature infant oral motor intervention for transition from gavage to full spoon feeding in preterm infants. METHODS: Preterm neonates born between 28 + 0-32 + 6 weeks gestation (n = 32) were randomised into an intervention group (premature infant oral motor intervention) for five minutes twice a day along with routine care (n = 16) and a control group (routine care, n = 16) once they reached a feed volume of at least 150 ml/kg/day administered by gavage method. The primary outcome measure was time (in days) to transition from gavage to full spoon feeds. RESULTS: The mean (SD) time to transition from gavage to full spoon feeds was attained significantly earlier in the intervention group than the control group (9.93 [5.83] vs 16.43 [10.46] days; mean difference, -6.5 days; 95% CI, -12.58 to -0.41). There was no significant difference between the two groups in terms of the duration of hospital stay, rates of physiological stability, and culture positive sepsis. CONCLUSION: Premature infant oral motor intervention, as used in this specific population, significantly reduces the time to transition to full spoon feeds without increasing culture positive sepsis and physiological instability.