Gut Microbiota In Rats Research Articles

Arabinoxylan from pearl millet bran: Optimized extraction, structural characterization, and its bioactivities

Arabinoxylan (AX) from cereals and millets have garnered attention due to the myriad of their bioactivities. Pearl millet (Pennisetum glaucum) bran, an underexplored milling by-product was used to extract AX (PMAX) by optimized alkali-assisted extraction using Response Surface Methodology and Central Composite Design, achieving a yield of 15.96 ± 0.39 % (w/w) under optimal conditions (0.57 M NaOH, 1:17 g/mL solid-to-liquid ratio, 60 °C, 4 h). Structural analysis revealed that PMAX was primarily composed of arabinose, xylose, glucose, galactose, and mannose (molar ratio 45.1:36.1:10.4:7.1:1.8), with a highly substituted (1 → 4)-linked β-D-xylopyranose backbone and a molecular weight of 794.88 kDa. PMAX displayed a significant reducing power of 0.617, metal chelating activity of 51.72 %, and DPPH, and ABTS radical scavenging activities (64.43 and 75.4 %, respectively at 5 mg/mL). It also demonstrated anti-glycation effects by inhibiting fructosamine (52.5 %), protein carbonyl (53.6 %), and total advanced glycation end products (77.0 %) formation, and reduced protein oxidation products such as dityrosine (84.7 %), kynurenine (80.2 %), and N′-formyl-kynurenine (50.0 %) at 5 mg/mL. PMAX induced the growth of Lactobacillus spp. in vitro and modulate gut microbiota in male Wistar rats by increasing Bacteroidetes and decreasing Firmicutes. These results provide a basis for further research on pearl millet arabinoxylan and its possible nutraceutical application.

Metagenomic analysis of rats with diarrhea treated with mixed probiotics: response to consecutive and alternate-hour supplementation.

Diarrhea is the leading contributory factor of sickness and mortality among children under five and an economic burden for families. This study aimed to investigate the effects of mixed probiotics supplementation at different times (consecutive and alternate-hour) on intestinal microecology in Sprague-Dawley (SD) rats with acute diarrhea. A total of 40 SD rats were randomly assigned to four groups, including the control group, model group, probiotic group A, and probiotic group B. An acute diarrhea model was induced by administration of 5% dextran sulfate sodium. Rats in probiotic group A and probiotic group B were fed with Clostridium butyricum (C. butyricum), Bifidobacterium infantis (B. infantis), and Saccharomyces boulardii (S. boulardii) for a total of 7 days. Probiotic group A was fed with all probiotics simultaneously. Probiotic group B was fed with C. butyricum and B. infantis simultaneously, and then after a 2-hour interval, with S. boulardii. Metagenomic next-generation sequencing was used to analyze the fecal samples from every rat. The metagenomic sequencing used in this experiment was used to evaluate the effect of probiotics on the composition as well as function of the gut microbiota in order to gain a deeper comprehension of probiotic-host interactions on health and disease. The structure of the gut microbiota in probiotic group A showed significant changes. Compared to the model group, the abundance of some beneficial bacteria had increased, including Actinobacteria (P=0.048), Lactobacillus (P=0.050), and Lactobacillus johnsonii (P=0.042), and many opportunistic pathogenic bacteria has decreased, such as Ruminococcus (P=0.001). Compared to the control group, the abundance of some beneficial bacteria had increased, including Fusobacteria (P=0.02) and Phascolarium (P=0.002), and there was a reduction in the abundance of many opportunistic pathogenic bacteria such as Roseburia (P=0.03), Lachnoclosterium (P=0.009), and Oscillibacter_sp_1-3 (P=0.002). In addition, metagenomic analysis showed that as well as an up-regulation of glycoside hydrolase expression, amino acid and inorganic ion transport, and metabolism-related pathways, there was a down-regulation of cell motility. Simultaneous administration of probiotics may have more positive implications in improving the gut microbiota of acute diarrhea rats.

The protective effect of S-adenosylmethionine on chronic adolescent stress-induced depression-like behaviors by regulating gut microbiota

The efficacy and tolerability of current antidepressants for adolescent depression are inadequate. S-adenosylmethionine (SAMe), known for its effectiveness and minimal side effects in adult depression, remains unstudied in adolescents. This study explored the potential of SAMe to address depression-like behaviors in juvenile rats induced by chronic unpredictable mild stress (CUMS), with a focus on gut microbiome interactions. Adolescent male Wistar rats were subjected to a 4-week CUMS regimen and received daily intraperitoneal injections of 300 mg/kg SAMe. Behavioral assessments included the sucrose preference test, elevated plus maze test, open field test, and Y-maze test. Histopathological changes of the hippocampus and colon were observed by Nissl staining and hematoxylin and eosin staining, respectively. Gut microbiome composition was analyzed using Accurate 16S absolute quantification sequencing. The results showed that SAMe significantly improved behavioral outcomes, reduced histopathological damages in hippocampal neurons and colon tissues, and modulated the gut microbiota of depressed rats. It favorably altered the ratio of Bacteroidetes to Firmicutes, decreased the absolute abundance of Deferribacteres, and adjusted levels of key microbial genera associated with depression-like behaviors. These results suggested that SAMe could effectively counter depression-like behaviors in CUMS-exposed adolescent rats by mitigating hippocampal neuronal and colon damage and modulating the gut microbiota. This supports SAMe as a viable and tolerable treatment option for adolescent depression, highlighting the importance of the gut-brain axis in therapeutic strategies.

Early and late gut microbiota signatures of stroke in high salt-fed stroke-prone spontaneously hypertensive rats

The high salt-fed stroke-prone spontaneously hypertensive rat (SHRSP) is a suitable tool to study the mechanisms underlying stroke pathogenesis. Salt intake modifies the gut microbiota (GM) in rats and humans and alterations of the GM have previously been associated with increased stroke occurrence. We aimed to characterize the GM profile in SHRSPs fed a high-salt stroke-permissive diet (Japanese diet, JD), compared to the closely related stroke-resistant control (SHRSR), to identify possible changes associated with stroke occurrence. SHRSPs and SHRSRs were fed a regular diet or JD for 4 weeks (short-term, ST) or a maximum of 10 weeks (long-term, LT). Stroke occurred in SHRSPs on JD-LT, preceded by proteinuria and diarrhoea. The GM of JD-fed SHRSPs underwent early and late compositional changes compared to SHRSRs. An overrepresentation of Streptococcaceae and an underrepresentation of Lachnospiraceae were observed in SHRSPs JD-ST, while in SHRSPs JD-LT short-chain fatty acid producers, e.g. Lachnobacterium and Faecalibacterium, decreased and pathobionts such as Coriobacteriaceae and Desulfovibrio increased. Occludin gene expression behaved differently in SHRSPs and SHRSRs. Calprotectin levels were unchanged. In conclusion, the altered GM in JD-fed SHRSPs may be detrimental to gut homeostasis and contribute to stroke occurrence.

Blueberry extract for the treatment of ischaemic stroke through regulating the gut microbiota and kynurenine metabolism.

Although the gut microbiota and kynurenine (KYN) metabolism have significant protective effects against ischaemic stroke (IS), the exact mechanism has yet to be fully elucidated. Combined serum metabolomics and 16S rRNA gene sequencing were used to reveal the differences between the gut microbiota and metabolites in rats treated with or without blueberry extract. Faecal microbiota transplantation (FMT) was employed to validate the protective role of the gut microbiota in IS. Furthermore, the interaction between Prevotella and IS was also confirmed in patients. Rats with IS experienced neurological impairments accompanied by an impaired intestinal barrier and disturbed intestinal flora, which further contributed to heightened inflammatory responses. Furthermore, Prevotella played a critical role in IS pathophysiology, and a positive correlation between Prevotella and KYN was detected. The role of KYN metabolism in IS was further demonstrated by the finding that IDO was significantly upregulated and that the use of the IDO inhibitor, attenuated KYN metabolic pathway activity and ameliorated neurological damage in rats with IS. Prevotella intervention also significantly improved stroke symptoms and decreasing KYN levels in rats with IS. FMT showed that the beneficial effects of blueberry extract on IS involve gut bacteria, especially Prevotella, which were confirmed by microbiological analyses conducted on IS patients. Moreover, blueberry extract led to significant changes in kynurenic acid levels and tryptophan and IDO levels through interactions with Prevotella. Our study demonstrates for the first time that blueberry extract could modulate "intestinal microecology-KYN metabolism" to improve IS.

Obesity as Inducer of Cognitive Function Decline via Dysbiosis of Gut Microbiota in Rats.

Diet-induced obesity is a global phenomenon that affects the population worldwide with manifestations at both the phenotypic and genotypic levels. Cognitive function decline is a major global health challenge. The relation between obesity and cognitive function is a debatable issue. The main goal of the current research was to study the implications of obesity on cognitive function and gut microbiota diversity and its impact on plasma and brain metabolic parameters in rats. Obesity was induced in rats by feeding on a high-fat (HF) or a high-fat/high-sucrose (HFHS) diet. The results reveal that both the HF (0.683) and HFHS (0.688) diets were effective as obesity inducers, which was confirmed by a significant increase in the body mass index (BMI). Both diet groups showed dyslipidemia and elevation of oxidative stress, insulin resistance (IR), and inflammatory markers with alterations in liver and kidney functions. Obesity led to a reduction in cognitive function through a reduction in short-term memory by 23.8% and 30.7% in the rats fed HF and HFHS diets, respectively, and learning capacity and visuo-spatial memory reduced by 8.9 and 9.7 s in the rats fed an HF or HFHS diet, respectively. Bacteroidetes, Firmicutes, Proteobacteria, Fusobacteria, and Spirochaetes phyla were detected. The Firmicutes/Bacteroidetes ratio (F/B) significantly decreased in the HF group, while it increased in the HFHS group compared to the normal control. The two species, Bacteroides acidifaciens and Bacteroides ovatus, which are associated with IR, were drastically compromised by the high-fat/high-sucrose diet. Some species that have been linked to reduced inflammation showed a sharp decrease in the HFHS group, while Prevotella copri, which is linked to carbohydrate metabolism, was highly enriched. In conclusion: Obesity led to cognitive impairment through changes in short-term and visuo-spatial memory. A metagenomic analysis revealed alterations in the abundance of some microbial taxa associated with obesity, inflammation, and insulin resistance in the HF and HFHS groups.

Mechanism of Action of Qingrekasen Granules in Alleviating Nephrotic Syndrome Evaluated by a Multi-Omics Approach

Objectives In this study, the efficacy of and mechanism of Qingrekasen Granules (QRKSG) is evaluated by metabolomics and transcriptomics using adriamycin (ADR)-induced nephrotic syndrome (NS) in rat model. Methods The model, benazepril, and QRKSG group received a single injection of 6.5 mg/kg ADR via the tail vein of the rats. The untreated group received an equal saline injection. The administration of drugs by gavage began after completing the modeling for one week. Benazepril was given at 0.9 mg/kg/d to the benazepril group and QRKSG was given at 1.62 g/kg/d to the QRKSG group. During gavage, 24 h urine was collected weekly. After four weeks of gavage, rats were anesthetized, and we collected the serum, feces, and kidney samples. The protective effect of QRKSG on NS was assessed by the detection of proteins in the urine at 24 h and serum biochemical indexes, as well as histopathological observation, TUNEL assay, and Western Blot of kidney samples. Moreover, gas chromatography-mass spectrometry (GC-MS) metabolomics sequencing of kidney metabolites helped investigate the significant differential metabolites produced by QRKSG that are implicated in ameliorating the pathological damage to the kidneys of NS rats. Subsequently, the significant targets of QRKSG that had an impact on the action of drugs were investigated by a transcriptome sequencing analysis. The correlation between both sets was also investigated. In addition, the effect of QRKSG on the gut microbiota of NS rats was investigated. Finally, the core targets were validated by molecular docking. Results The results indicated that QRKSG possess significant renoprotective effects in NS rats by reversing the abnormal urinary protein content and serum biochemical disorders, as well as improving renal pathological damage. Multiple genes and metabolites were shown to be back-regulated after QRKSG delivery, based on further multi-omics studies. The integrated metabolomics and transcriptomics analysis showed that QRKSG alleviated NS mainly by regulating amino acid metabolic pathways. Gut microbiota analysis demonstrated that QRKSG could alleviate NS by improving gut microbiota. The molecular docking results showed good binding ability of the QRKSG active ingredient to the core target, and among them, the ingredients with the best docking effect were mainly flavonoids and phenolic acid ingredients. The combined metabolomics and transcriptomics study findings were validated through a TUNEL assay and a Western Blot analysis. Conclusion We have concluded that ADR-induced NS in rats can be treated with QRKSG. The mechanisms used by QRKSG to reduce the symptoms of NS are through the multi-component, multi-target, and multi-pathway therapeutic modulation of inflammation, oxidative stress, energy homeostasis, and apoptosis. Additionally, QRKSG could alleviate NS by regulating gut microbiota.

Non-invasive ventilation restores the gut microbiota in rats with acute heart failure

Heart failure (HF) is an increasingly prevalent disease in humans; it induces multiple symptoms and damages health. The animal gut microbiota has critical roles in host health, which might be related to HF symptoms. Currently, several options are used to treat HF, including non-invasive ventilation (NIV). However, studies on gut microbiota responses to acute HF and associated treatments effects on gut communities in patients are scarce. Here, short-term (1 week after treatments) and long-term (3 months after treatment) variations in gut microbiota variations in rats with acute HF treated were examined NIV through high-throughput sequencing of the bacterial 16S rRNA gene. Through comparison of gut microbiota alpha diversity, it was observed lower gut microbiota richness and diversity in animals with acute HF than in normal animals. Additionally, beta-diversity analysis revealed significant alterations in the gut microbiota composition induced by acute HF, as reflected by increased Firmicutes/Bacteroidetes (F/B) ratios and Proteobacteria enrichment. When network analysis results were combined with the null model, decreased stability and elevated deterministic gut microbiota assemblies were observed in animals with acute HF. Importantly, in both short- and long-term periods, NIV was found to restore gut microbiota dysbiosis to normal states in acute HF rats. Finally, it was shown that considerable gut microbiota variations existed in rats with acute HF, that underlying microbiota mechanisms regulated these changes, and confirmed that NIV is suitable for HF treatment. In future studies, these findings should be validated with different model systems or clinical samples.

Electroacupuncture at different frequencies improves visceral pain in IBS rats through different pathways.

The aim of this study was to investigate the frequency dependence of electroacupuncture (EA) in alleviating chronic visceral pain in patients with irritable bowel syndrome (IBS) and the differences in the gut microbiota and metabolites as potential mechanisms to explain frequency dependence. A visceral hyperalgesia model was established by colorectal instillation of 2,4,6-trinitrobenzene sulfonic acid in rats, and EA treatment at 2/10 Hz, 2/50 Hz and 2/100 Hz was applied at ST25. Visceral sensation was quantified by the abdominal withdrawal reflex score and the area under the curve of the rectus abdominis electromyogram in response to colorectal distension. Ultrastructural morphological damage of colonic tissue of the rats was examined by transmission electron microscopy. 16S rRNA gene sequencing and 1H-nuclear magnetic resonance spectroscopy were applied to study the differences in the gut microbiota and to perform metabonomic profiling of the colonic tissue. EA at ST25 at different frequencies attenuated chronic visceral pain, ultrastructural morphological damage to colonic tissue and disruption of the gut microbiota in IBS rats. The frequency of 2/100 Hz has more regulatory pathways than 2/10 Hz and 2/50 Hz. In addition, IBS rats exhibited colonic metabolic disorders, and pantothenate was significantly upregulated after EA treatment at different frequencies. Very low-density lipoprotein and 2-hydroxybutyrate were significantly increased in the 2/10 Hz group, while low density lipoprotein, very low-density lipoprotein, 2-hydroxybutyrate, methylmalonate and alpha-hydroxyisobutyric acid were significantly increased in the 2/100 Hz group. EA at ST25 at different frequencies attenuated chronic visceral pain through different gut microbiota and metabolic pathways.

Acupuncture ameliorates depression-like behavior of poststroke depression model rats through the regulation of gut microbiota and NLRP3 inflammasome in the colon.

This study was conducted to examine the effects of acupuncture on gut microbiota and expression of NLRP3 inflammasome in the colon in poststroke depression (PSD) model rats. Sprague-Dawley male rats were randomized into four groups: sham surgery group, poststroke depression group, acupuncture group, and probiotics group. Acupuncture therapy at Baihui (GV20), Shenting (GV24), bilateral Zusanli (ST36) acupoints in the acupuncture group and probiotic gavage therapy in the probiotics group were performed once per day for 2 weeks. Behaviors of depression were assessed by using weight measurements, sucrose preference test, open field test, and forced swimming test. Histopathological alterations in the colon were determined by hematoxylin-eosin staining, the expression of NLRP3/ASC/caspase-1 pathway-related proteins was analyzed by western blotting. Serum levels of IL-1β and IL-18 were derived from ELISA. The 16S rRNA gene sequencing was performed to examine and analyze the differences of gut microbiota of rats among all groups. Acupuncture was effective to increase weight and ameliorate depressive-like behaviors in PSD rats. Acupuncture increased the diversity of gut microbiota, upregulated the abundance of Bifidobacteriaceae and Lactobacillaceae, and decreased the relative abundance of Peptostreptococcaceae, Rikenellaceae, Eggerthellaceae, and Streptococcaceae at family level. Acupuncture effectively improved the pathological changes in the colon. Meanwhile, acupuncture reduced NLRP3, ASC, caspase-1 protein expressions in the colon, and serum levels of IL-18 and IL-1β. Acupuncture may reduce depressive-like behaviors of PSD by regulating the gut microbiota and suppressing hyperactivation of NLRP3 inflammasome in the colon. Microbiota-gut-brain axis may be an effective target pathway for acupuncture treatment of PSD.

Changes in the gut microbiota induced by an oral formulation of multiple peptides and plants contribute to its antihypertensive effects

The homeostasis of the gut microbiota is a crucial factor in regulating peripheral and central blood pressure. Formulating a food-derived mixture of antioxidants, anti-inflammatory compounds and prebiotics to maintain the homeostasis of the gut microbiota will be essential for preventing and alleviating hypertension. Although bioactive peptides and plant extracts have been demonstrated not only to be excellent antioxidants and anti-inflammatory agents but also to promote the homeostasis of the microbiota, few studies have investigated the influence of multiple peptides mixed with plant extracts on the gut microbiota of hypertensive rats. This is the first study to characterize the fecal microbiome of spontaneously hypertensive rats supplemented with a mixture of multiple peptides and plant extracts by integrating 16 S rRNA gene sequencing. During the six-week experiment, the animals were healthy and without mortality. The results revealed that oral supplementation with the formulation reduced both systolic and diastolic blood pressure, improved the gut microbiota by increasing the ratio of Bacteroidetes to Firmicutes, and increased the relative abundance of specific genera, such as Lactobacillus. This study suggested that a synergistic formulation of multiple peptides mixed with plant extracts could be a novel strategy for preventing and alleviating hypertensive diseases.Graphical

Hong Guo Ginseng Guo (HGGG) protects against kidney injury in diabetic nephropathy by inhibiting NLRP3 inflammasome and regulating intestinal flora

BackgroundDiabetic nephropathy (DN) is one of the most serious complications of diabetes which leads to end-stage renal failure and approximately one-third of patients need dialysis. There is still a lack of effective and specific treatment for DN. Searching new drugs from natural foods is an alternative approach to treat diabetes and its complications. Hong Guo Ginseng Guo (HGGG), a berry with palatability and nutritional benefits, has exhibited medicinal properties to mitigate the progression of DN. PurposeThis study investigates the effects of HGGG on streptozotocin (STZ)-induced diabetic nephropathy (DN) in rats and elucidates the mechanisms underlying its reno-protective and diabetes management benefits. MethodsThe LC-MS spectra method identified the primary ingredients in HGGG. To induce DN, male Sprague-Dawley (SD) rats received a single intraperitoneal injection of 75 mg/kg STZ. Over an eight-week treatment period, we assessed biochemical parameters including blood glucose, urine albumin-to-creatinine ratio (UACR), blood urea nitrogen (BUN), and urine N-acetyl-beta-d-glucosaminidase (NAG). Tissue pathology was examined using Masson's trichrome, Periodic Acid-Schiff (PAS), and Hematoxylin-Eosin (H&E) stains. We analyzed pro-inflammatory mediators and tissue fibrosis extent using Western blotting and immunohistochemistry. Gut microbiota composition was characterized via 16S rDNA sequencing. ResultsSeventeen chemical compounds were identified, with lobetyolin, luteolin, and rutin highlighted as the primary active elements. HGGG extract appeared to confer renal protection, demonstrated by improvements in UACR, BUN, and urine NAG levels. The reno protective effects in HGGG-treated DN rats were linked to reduced renal fibrosis and inhibition of the NLRP3 inflammasome. Additionally, HGGG administration improved gut barrier integrity and altered the gut microbiota in DN rats, increasing the relative abundance of beneficial bacteria known for regulating polyamines and producing short-chain fatty acids (SCFAs), including Ruminococcus, Barnesiella_sp, Anaerovoracaceae, and Prevotellaceae_NK3B31. Meanwhile, treatment with HGGG decreasing the presence of Oscillospira, potential pathogens responsible for producing lipopolysaccharide (LPS). ConclusionHGGG has potential as a beneficial fruit for managing diabetes and its associated complications through modulation of the gut microbiota.

Exploring the effects of Saorilao-4 on the gut microbiota of pulmonary fibrosis model rats based on 16S rRNA sequencing.

Pulmonary fibrosis (PF) is a progressive and incurable lung disease for which treatment options are limited. Here, we aimed to conduct an exploratory study on the effects of the Mongolian medicine Saorilao-4 (SRL) on the gut microbiota structure, species abundance, and diversity of a rat PF model as well as the mechanisms underlying such effects. Rat fecal samples were analyzed using 16S rRNA sequencing technology. Bioinformatic and correlation analyses were performed on microbiota data to determine significant associations. SRL substantially attenuated the adverse effects exerted by PF on the structure and diversity of gut microbiota while regulating its alpha and beta diversities. Linear discriminant analysis effect size enabled the identification of 62 differentially abundant microbial taxa. Gut microbiota abundance analysis revealed that SRL significantly increased the relative abundance of bacterial phyla such as Firmicutes and Bacteroidetes. Moreover, SRL increased the proportion of beneficial bacteria, such as Lactobacillus and Bifidobacteriales, decreased the proportion of pathogenic bacteria, such as Rikenellaceae, and balanced the gut microbiota by regulating metabolic pathways. SRL may attenuate PF by regulating gut microbiota. This exploratory study establishes the groundwork for investigating the metagenomics of PF.

Berberine attenuates 5-fluorouracil-induced intestinal mucosal injury by modulating the gut microbiota without compromising its anti-tumor efficacy

Background5-Fluorouracil (5-Fu), a prominent chemotherapeutic agent for colorectal cancer (CRC) treatment, is often associated with gastrointestinal toxicities, particularly diarrhea. Our previous study demonstrated that berberine (BBR) ameliorates 5-Fu-induced intestinal mucosal injury by modulating the gut microbiota in rats. Nevertheless, the precise molecular mechanism underlying BBR's protective effect on intestinal mucosa remains elusive, and its impact on the anti-tumor efficacy of 5-Fu warrants further investigation. MethodsThe effect of BBR on 5-Fu-induced intestinal mucosal injury was investigated using a tumor-bearing murine model, employing H&E staining, 16 S rDNA sequencing, transcriptome sequencing, Western blot analysis, cell experiments and constructing a pseudo-germ-free tumor xenograft model. ResultOur findings demonstrate that BBR alleviates intestinal mucosal damage, reduces the levels of inflammatory factors (IL-6, TNF-α, and IL-1β), and inhibits epithelial cell apoptosis in 5-Fu-treated mice without compromising 5-Fu's anti-tumor efficacy. Moreover, 16 S rDNA sequencing indicated that BBR significantly increases the abundance of Akkermansia and decreases the abundance of pathogenic bacteria Escherichia/Shigella at the genus level. Mechanistically, transcriptome sequencing and Western blot analysis confirmed that BBR upregulates PI3K/AKT/mTOR expression in the intestinal mucosa. However, this effect was not observed in tumor tissues. Notably, BBR did not demonstrate a direct protective effect on 5-Fu-treated CCD841 and SW480 cells. Additionally, BBR had no effect on the PI3K/AKT/mTOR pathway in the intestinal tissue of the 5-Fu-treated mouse model with a depleted gut microbiota. ConclusionThis study indicates that BBR alleviates 5-Fu-induced intestinal mucosal injury by modulating the gut microbiota and regulating the PI3K/AKT/mTOR signaling pathway without compromising the anti-tumor efficacy of 5-Fu.

Probiotics Alter the Microbial and Behavioral Consequences of Methamphetamine Exposure in a Sex-Selective Manner

Methamphetamine use disorder (MuD) is a global health problem, with no FDA-approved medications. Our prior work demonstrated that repeated methamphetamine exposure alters the gut microbiota in male rats and results in depressive-like behaviors. In this study, we extend our findings to females and determine whether probiotics block these effects. Male and female rats were administered methamphetamine (2 mg/kg; SC) or saline twice daily with either a combination of two probiotics (Lactobacillus helveticus R0052 and Bifidobacterium longum R0175) or placebo solution for 14 days. Fecal samples were collected at baseline and other days after treatment cessation. Tests of anxiety- and depressive-like behaviors were conducted using open-field and forced-swim assays. Methamphetamine induced anxiety-like behavior in females and anxiety-like and depressive-like behaviors in males. Probiotics blocked the depressive-like effect in males but did not alter anxiety-like effects in either sex. Methamphetamine exposure decreased levels of alpha diversity in both sexes, but sex differences were seen in the ability of probiotics or methamphetamine to alter levels of various bacteria. These findings support the role of the gut–brain microbiome in the depressive effects of repeated methamphetamine exposure in males, suggesting that probiotics may be a viable treatment option for MuD.

Modified Zhizhu Pill improves the loperamide-induced slow transit constipation via gut microbiota and neurotransmitters in microbiota-gut-brain axis

BackgroundSlow-transmission constipation is a type of intractable constipation with unknown etiology and unclear pathogenesis. ObjectiveThe intention of this study was to evaluate the therapeutic effect and possible mechanism of Modified Zhizhu Pills on loperamide-induced slow transit constipation. MethodsThe effects of the Modified Zhizhu Pill were evaluated in a rat model of constipation induced by subcutaneous administration of loperamide. Fecal parameters (fecal count, fecal water content, and fecal hardness) were measured in constipated rats. The substance, target, and pathway basis of the Modified Zhizhu Pill on constipation was investigated using network pharmacology. The microflora in rats was determined. Serum neurotransmitters (acetylcholine and 5-hydroxytryptamine) were measured in rats and their relationship with the gut microbiota was assessed. ResultsModified Zhizhu Pill increased the number of bowel movements and fecal water content, and decreased fecal hardness and transit time. Network pharmacological analysis showed that Modified Zhizhu Pill can target multiple constipation-related targets and pathways through multiple potential active ingredients. Modified Zhizhu Pill alleviated loperamide-induced microbiota dysbiosis. Modified Zhizhu Pill increased serum 5-hydroxytryptamine and acetylcholine. The increase in serum 5-hydroxytryptamine and acetylcholine was associated with rat gut microbiota. ConclusionThese results suggest that Modified Zhizhu Pill may increase intestinal motility and ultimately relieve constipation by improving microecological dysbiosis and neurotransmission.

Characterization of Gut Microbiota in Rats and Rhesus Monkeys After Methamphetamine Self-administration.

Methamphetamine (MA) is one of the most abused drugs globally, but the mechanism of its addiction remains unclear. Several animal studies have shown that the gut microbiota (GM) influences addictive behaviors, but the pattern of GM changes during addiction in animals of different species remains unclear. The aim of this study was to explore the association between dynamic changes in GM and MA self-administration acquisitionamong two classical mammals, rhesus monkeys (Macaca mulatta) and rats, MA self-administration models. Male Sprague-Dawley rats and male rhesus monkeys were subjected to classical MA self-administration training, and fecal samples were collected before and after MA self-administration training, respectively. 16S rRNA sequencing was used for GM analyses. We found that GM changes were more pronounced in rats than in rhesus monkeys, as evidenced by more GM taxa producing significant differences before and after MA self-administration training in rats than in monkeys. We also found that the expression of the genus Clostridia_vadinBB60_group significantly decreased after MA self-administration training in both rats and rhesus monkeys. Lactobacillus changes were significantly negatively correlated with total MA uptake in rats (Pearson R = - 0.666, p = 0.035; Spearman R = - 0.721, p = 0.023), whereas its change was also highly negatively correlated with total MA uptake in rhesus monkeys (Pearson R = - 0.882, p = 0.118; Spearman R = - 1.000, p = 0.083), although this was not significant. These findings suggest that MA causes significant alterations in GM in both rhesus monkeys and rats and that the genus Lactobacillus might be a common therapeutic target for MA uptake prevention across the species.

Heat acclimation with probiotics-based ORS supplementation alleviates heat stroke-induced multiple organ dysfunction via improving intestinal thermotolerance and modulating gut microbiota in rats.

Heat stroke (HS) is a critical condition with extremely high mortality. Heat acclimation (HA) is widely recognized as the best measure to prevent and protect against HS. Preventive administration of oral rehydration salts III (ORSIII) and probiotics have been reported to sustain intestinal function in cases of HS. This study established a rat model of HA that was treated with probiotics-based ORS (ORSP) during consecutive 21-day HA training. The results showed that HA with ORSP could attenuate HS-induced hyperthermia by regulating thermoregulatory response. We also found that HA with ORSP could significantly alleviate HS-induced multiple organ injuries. The expression levels of a series of heat-shock proteins (HSPs), including HSP90, HSP70, HSP60, and HSP40, were significantly up-regulated from the HA training. The increases in intestinal fatty acid binding protein (I-FABP) and D-Lactate typically seen during HS were decreased through HA. The representative TJ proteins including ZO-1, E-cadherin, and JAM-1 were found to be significantly down-regulated by HS, but sustained following HA. The ultrastructure of TJ was examined by TEM, which confirmed its protective effect on the intestinal barrier protection following HA. We also demonstrated that HA raised the intestinal levels of beneficial bacteria Lactobacillus and lowered those of the harmful bacteria Streptococcus through 16S rRNA gene sequencing. These findings suggest that HA with ORSP was proven to improve intestinal thermotolerance and the levels of protective gut microbiota against HS.

Gut microbiota and serum metabolomic alterations in modulating the impact of fecal microbiota transplantation on ciprofloxacin-induced seizure susceptibility.

The gut microbiota and the microbiota-gut-brain axis have gained considerable attention in recent years, emerging as key players in the mechanisms that mediate the occurrence and progression of many central nervous system-related diseases, including epilepsy. In clinical practice, one of the side effects of quinolone antibiotics is a lower seizure threshold or aggravation. However, the underlying mechanism remains unclear. We aimed to unravel the intrinsic mechanisms through 16S rRNA sequencing and serum untargeted metabolomic analysis to shed light on the effects of gut microbiota in ciprofloxacin-induced seizure susceptibility and lithium pilocarpine-induced epilepsy rat models. We observed that ciprofloxacin treatment increased seizure susceptibility and caused gut dysbiosis. We also found similar changes in the gut microbiota of rats with lithium pilocarpine-induced epilepsy. Notably, the levels of Akkermansia and Bacteroides significantly increased in both the ciprofloxacin-induced seizure susceptibility and lithium pilocarpine-induced epilepsy rat models. However, Marvinbryantia, Oscillibacter, and Ruminococcaceae_NK4A214_group showed a coincidental reduction. Additionally, the serum untargeted metabolomic analysis revealed decreased levels of indole-3-propionic acid, a product of tryptophan-indole metabolism, after ciprofloxacin treatment, similar to those in the plasma of lithium pilocarpine-induced epilepsy in rats. Importantly, alterations in the gut microbiota, seizure susceptibility, and indole-3-propionic acid levels can be restored by fecal microbiota transplantation. In summary, our findings provide evidence that ciprofloxacin-induced seizure susceptibility is partially mediated by the gut microbiota and tryptophan-indole metabolism. These associations may play a role in epileptogenesis, and impacting the development progression and treatment outcomes of epilepsy.

Effect of dapagliflozin on ferroptosis through the gut microbiota metabolite TMAO during myocardial ischemia–reperfusion injury in diabetes mellitus rats

Dapagliflozin (DAPA) demonstrates promise in the management of diabetic mellitus (DM) and cardiomyopathy. Trimethylamine N-oxide (TMAO) is synthesized by the gut microbiota through the metabolic conversion of choline and phosphatidylcholine. Ferroptosis may offer novel therapeutic avenues for the management of diabetes and myocardial ischemia–reperfusion injury (IRI). However, the precise mechanism underlying ferroptosis in cardiomyocytes and the specific role of TMAO generated by gut microbiota in the therapeutic approach for DM and myocardial IRI utilizing DAPA need to be further explored. Nine male SD rats with specific pathogen-free (SPF) status were randomly divided equally into the normal group, the DM + IRI (DIR) group, and the DAPA group. The diversity of the gut microbiota was analyzed using 16S rRNA gene sequencing. Additionally, the Wekell technique was employed to measure the levels of TMAO in the three groups. Application of network pharmacology to search for intersection targets of DAPA, DIR, and ferroptosis, and RT-PCR experimental verification. Ultimately, the overlapping targets that were acquired were subjected to molecular docking analysis with TMAO. The changes of Bacteroidetes and Firmicutes in the gut microbiota of DIR rats were most significantly affected by DAPA. Escherichia-Shigella and Prevotella_9 within the phylum Bacteroidetes could be identified as the primary effects of DAPA on DIR. Compared with the normal group, the TMAO content in the DIR group was significantly increased, while the TMAO content in the DAPA group was decreased compared to the DIR group. For the network pharmacology analysis, DAPA and DIR generated 43 intersecting target genes, and then further intersected with ferroptosis-related genes, resulting in 11 overlapping target genes. The mRNA expression of ALB, HMOX1, PPARG, CBS, LCN2, and PPARA decreased in the DIR group through reverse transcription polymerase chain reaction (RT-PCR) validation, while the opposite trend was observed in the DAPA group. The docking score between TMAO and DPP4 was − 5.44, and the MM-GBSA result of − 22.02 kcal/mol. It epitomizes the finest docking performance among all the target genes with the lowest score. DAPA could reduce the levels of metabolite TMAO produced by gut microbiota, thereby regulating related target genes to decrease ferroptosis in DIR cardiomyocytes.