Moderating effect of salidroside on intestinal microbiota in mice exposed to PM2.5 / 环境与职业医学

Background Salidroside (SAL) has a protective effect on multiple organ systems. Exposure to fine particulate matter (PM2.5) in the atmosphere may lead to disruptions in gut microbiota and impact intestinal health. The regulatory effect of SAL on the gut microbiota of mice exposed to PM2.5 requires further investigation. Objective To evaluate gut microbiota disruption in mice after being exposed to PM2.5 and the potential effect of SAL. Methods Forty male C57BL/6 mice, aged 6 to 8 weeks, were randomly divided into four groups: a control group, an SAL group, a PM2.5 group, and an SAL+PM2.5 group, each containing 10 mice. In the SAL group and the SAL+PM2.5 group, the mice were administered SAL (60 mg·kg−1) by gavage, while in the control group and the PM2.5 group, sterile saline (10 mL·kg−1) was administered by gavage. In the PM2.5 group and the SAL+PM2.5 group, PM2.5 suspension (8 mg·kg−1) was intratracheally instilled, and in the control group and SAL group, sterile saline (1.5 mL·kg−1) was intratracheally administered. Each experiment cycle spanned 2 d, with a total of 10 cycles conducted over 20 d. Histopathological changes in the ileum tissue of the mice were observed after HE staining. Colon contents were collected for gut microbiota sequencing and short-chain fatty acids (SCFAs) measurements. Results The PM2.5 group showed infiltration of inflammatory cells in the ileum tissue, while the SAL+PM2.5 group exhibited only a small amount of inflammatory cell infiltration. Compared to the control group, the PM2.5 group showed decreased Shannon index (P<0.05) and increased Simpson index (P<0.05), indicating that the diversity of gut microbiota in this group was decreased; the SAL+PM2.5 group showed increased Shannon index compared to the PM2.5 group (P<0.05) and decreased Simpson index (P<0.05), indicating that the diversity of gut microbiota in mice intervened with SAL was increased. The principal coordinates analysis (PCoA) revealed a significant separation between the PM2.5 group and the control group, while the separation trend was less evident among the control group, the SAL group, and the SAL+PM2.5 group. The unweighted pair-group method with arithmetic means (UPGMA) clustering tree results showed that the control group and the SAL group clustered together first, followed by clustering with the SAL+PM2.5 group, and finally, the three groups clustered with the PM2.5 group. The PCoA and UPGMA clustering results indicated that the uniformity and similarity of the microbiota in the PM2.5 group were significantly decreased. Compared to the control group, the PM2.5 group showed decreased abundance of phylum Bacteroidetes and Candidatus_Saccharimonas (P<0.05) and increased abundance of phylum Proteobacteria, genus Escherichia, genus Bacteroides, genus Prevotella, genus Enterococcus, and genus Proteus (P<0.05). Compared to the PM2.5 group, the SAL+PM2.5 group showed decreased abundance of phylum Proteobacteria, phylum Actinobacteria, genus Prevotella, and genus Proteus (P<0.05), and increased abundance of Candidatus_Saccharimonas (P<0.05). The PM2.5 group showed reduced levels of propionic acid, valeric acid, and hexanoic acid compared to the control group (P<0.05), while the SAL+PM2.5 group showed increased levels of propionic acid, isobutyric acid, butyric acid, valeric acid, and hexanoic acid compared to the PM2.5 group (P<0.05). Conclusion Exposure to PM2.5 can cause pathological alterations, microbial dysbiosis, and disturbing production of SCFAs in intestinal tissue in mice. However, SAL can provide a certain degree of protective effect against these changes.

Effect of Gegen Qinliantang on Fecal Short-chain Fatty Acids in Rats with Antibiotic-associated Diarrhea Based on Targeted Metabonomics / 中国实验方剂学杂志

ObjectiveTo explore the impact of Gegen Qinliantang（GQT） on the fecal short-chain fatty acids（SCFAs） metabolism in antibiotic-associated diarrhea（AAD） through targeted metabolomics. MethodA total of 240 SD rats were randomly divided into six groups（n=40， half male and half female）， including blank group， model group， bifidobiogen group（0.15 g·kg-1）， and GQT high-， medium-， and low-dose groups（10.08， 5.04， 2.52 g·kg-1）， except for the blank group， clindamycin（250 mg·kg-1） was given to all groups by gavage for modeling every day for 7 d. After successful modeling， each administered group was gavaged with the corresponding dose of the drug， and the blank and model groups were gavaged with an equal volume of normal saline solution， 1 time/d， for 14 d. At 0， 3， 7， 14 d after the drug intervention， eight rats were randomly selected from each group， respectively. Gas chromatography-time-of-flight mass spectrometry（GC-TOF-MS） was used to perform targeted metabolomic analysis of SCFAs in the feces of rats， and partial least squares-discriminant analysis（PLS-DA） was applied to compare the differences in metabolic profiles between groups at different treatment times， and to compare the changes in the contents of SCFAs in rat feces between groups. ResultPLS-DA results showed that the blank group could be clearly distinguishable from the model group， with GQT exhibiting a closer proximity to the blank group after 7 d of treatment. After further analyzing the composition of SCFAs， it was found that the proportion of acetic acid increased and the proportions of butyric acid， valeric acid， hexanoic acid and isovaleric acid decreased in the model group compared with the blank group. After the treatment with GQT， the proportions of butyric acid， isobutyric acid， valeric acid， and isovaleric acid increased， and the proportions of acetic acid， propionic acid and caproic acid decreased. Subsequent differential analysis revealed that GQT could significantly improve the content of butyric acid， and had a certain retrogressive effect on the contents of valeric acid and hexanoic acid. ConclusionThe medium dose group of GQT can improve the contents of SCFAs in AAD feces after 7 days of treatment， which may be related to the improvement of the composition ratio of SCFAs and the contents of butyric acid， valeric acid and caproic acid.

Potential efficacy and mechanism of eight mild-natured and bitter-flavored TCMs based on gut microbiota: A review / 中草药·英文版

The mild-natured and bitter-flavored traditional Chinese medicines (MB-TCMs) are an important class of TCMs that have been widely used in clinical practice and recognized as safe long-term treatments for chronic diseases. However, as an important class of TCMs, the panorama of pharmacological effects and the mechanisms of MB-TCMs have not been systemically reviewed. Compelling studies have shown that gut microbiota can mediate the therapeutic activity of TCMs and help to elucidate the core principles of TCM medicinal theory. In this systematic review, we found that MB-TCMs commonly participated in the modulation of metabolic syndrome, intestinal inflammation, nervous system disease and cardiovascular system disease in association with promoting the growth of beneficial bacteria Bacteroides, Akkermansia, Lactobacillus, Bifidobacterium, Roseburia as well as inhibiting the proliferation of harmful bacteria Helicobacter, Enterococcus, Desulfovibrio and Escherichia-Shigella. These alterations, correspondingly, enhance the generation of protective metabolites, mainly including short-chain fatty acids (SCFAs), bile acid (BAs), 5-hydroxytryptamine (5-HT), indole and gamma-aminobutyric acid (GABA), and inhibit the generation of harmful metabolites, such as proinflammatory factors trimethylamine oxide (TAMO) and lipopolysaccharide (LPS), to further exert multiplicative effects for the maintenance of human health through several different signaling pathways. Altogether, this present review has attempted to comprehensively summarize the relationship between MB-TCMs and gut microbiota by establishing the TCMs-gut microbiota-metabolite-signaling pathway-diseases axis, which may provide new insight into the study of TCM medicinal theories and their clinical applications.

Effect of Atractylodis Macrocephalae Rhizoma on Short-chain Fatty Acids and Intestinal Barrier in Mice with Slow-transit Constipation / 中国实验方剂学杂志

ObjectiveTo investigate the mechanism of Atractylodis Macrocephalae Rhizoma（AMR） in the treatment of slow-transmission constipation（STC） by observing the effects of AMR on short-chain fatty acids and intestinal barries in STC mice. MethodForty-eight male KM mice were randomly divided into blank group， model group， AMR low-， medium-， high-dose groups（2.5， 5， 10 g·kg-1） and mosapride group（2.5 mg·kg-1）. Except for the blank group， all groups were gavaged with loperamide suspension（5 mg·kg-1） twice daily for 14 d to construct the STC mouse model. At the same time， each drug administration group was given the corresponding drug by gavage for consecutive 14 d， the blank and model groups were gavaged with equal volume of distilled water. The effects of the treatment of AMR on body mass， defecation frequency， fecal water content and intestinal propulsion rate of mice were observed， the pathological changes of mouse colon were observed by hematoxylin-eosin（HE） staining and periodic acid-Schiff（PAS） staining， the levels of gastrin（GAS） and motilin（MTL） in serum were detected by enzyme-linked immunosorbent assay（ELISA）， gas chromatography-mass spectrometry（GC-MS） was used to detect the contents of short-chain fatty acids（SCFAs） in mouse feces， real-time fluorescence quantitative polymerase chain reaction（Real-time PCR） and Western blot were used to determine the mRNA and protein expression levels of zonula occludens-1（ZO-1）， Occludin， and Claudin-1 in the colon of mice. ResultCompared with the blank group， the body mass， defecation frequency， fecal water content and intestinal propulsion rate of mice in the model group were significantly decreased（P<0.05， P<0.01）， the arrangement of colonic tissues was disordered， and the number of goblet cells was reduced， the levels of GAS and MTL in serum were significantly decreased（P<0.01）， and the levels of SCFAs in the feces were on a decreasing trend， with the contents of acetic acid， propionic acid， butyric acid， isobutyric acid and valeric acid were significantly decreased（P<0.05， P<0.01）， the mRNA and protein expression levels of ZO-1， Occludin and Claudin-1 in the colonic tissues were significantly decreased（P<0.01）. The above results suggested that STC mouse model was successfully constructed. Compared with the model group， the body mass， defecation frequency， fecal water content and intestinal propulsion rate of mice in AMP administration groups all increased significantly（P<0.05， P<0.01）， the mucosal layer of the colonic tissues was structurally intact without obvious damage， and the number of goblet cells increased， serum levels of GAS and MTL were significantly increased（P<0.01）， the contents of SCFAs in the feces were all on a rising trend， with the contents of acetic， propionic， butyric and isobutyric acids rising significantly（P<0.05， P<0.01）， the mRNA and protein expression levels of ZO-1， Occludin and Claudin-1 in the colonic tissues were significantly increased（P<0.05， P<0.01）. ConclusionAMR is able to improve the constipation symptoms in STC mice， and its mechanism may be related to increasing the contents of SCFAs in the intestine as well as promoting the mRNA and protein expression levels of ZO-1， Occludin and Claudin-1 in the colon.

Jujubae Fructus alleviates intestinal injury caused by toxic medicinals in Shizao Decoction based on correlation between intestinal flora and host metabolism / 中国中药杂志

Genkwa Fols, Kansui Radix, and Euphorbiae Pekinensis Radix in Shizao Decoction(SZD) are toxic to intestinal tract. Jujubae Fructus in this prescription can alleviate the toxicity, but the mechanism is still unclear. Therefore, this study aims to explore the mechanism. To be specific, 40 normal Sprague-Dawley(SD) rats were classified into the normal group, high-dose and low-dose SZD groups, and high-dose and low-dose SZD without Jujubae Fructus(SZD-JF) groups. The SZD groups were given(ig) SZD, while SZD-JF groups received the decoction without Jujubae Fructus. The variation of body weight and spleen index were recorded. The patho-logical changes of intestinal tissue were observed based on hematoxylin and eosin(HE) staining. The content of malondialdehyde(MDA) and glutathione(GSH) and activity of superoxide dismutase(SOD) in intestinal tissue were measured to evaluate the intestinal injury. Fresh feces of rats were collected to detect intestinal flora structure by 16S ribosomal RNA gene(16S rDNA) sequencing technology. The content of fecal short chain fatty acids and fecal metabolites was determined by gas chromatography-mass spectrometer(GC-MS) and liquid chromatography-mass spectrometer ultra-fast liquid chromatography-quadrupole-time-of-flight mass spectrometer(UFLC-Q-TOF-MS), separately. Spearman's correlation analysis was employed to analyze the differential bacteria genera and differential metabolites. RESULTS:: showed that high-dose and low-dose SZD-JF groups had high content of MDA in intestinal tissue, low GSH content and SOD activity, short intestinal villi(P<0.05), low diversity and abundance of intestinal flora, variation in the intestinal flora structure, and low content of short chain fatty acids(P<0.05) compared with the normal group. Compared with high-dose and low-dose SZD-JF groups, high-dose and low-dose SZD groups displayed low content of MDA in intestinal tissue, high GSH content and SOD activity, recovery of the length of intestinal villi, increased abundance and diversity of intestinal flora, alleviation of dysbacteria, and recovery of the content of short chain fatty acids(P<0.05). According to the variation of intestinal flora and fecal metabolites after the addition of Jujubae Fructus, 6 differential bacterial genera(Lactobacillus, Butyricimonas, Clostridia＿UCG-014, Prevotella, Escherichia-Shigella, Alistipes),4 differential short chain fatty acids(such as acetic acid, propionic acid, butyric acid, valeric acid) and 18 differential metabolites(such as urolithin A, lithocholic acid, and creatinine) were screened out. Beneficial bacteria such as Lactobacillus were in positive correlation with butyric acid and urolithin A(P<0.05). The pathogenic bacteria such as Escherichia-Shigella were in negative correlation with propionic acid and urolithin A(P<0.05). In summary, SZD-JF caused obvious intestinal injury to normal rats, which could lead to intestinal flora disorder. The addition of Jujubae Fructus can alleviate the disorder and relieve the injury by regulating intestinal flora and the metabolites. This study discusses the effect of Jujubae Fructus in relieving the intestinal injury caused by SZD and the mechanism from the perspective of intestinal flora-host metabolism, which is expected to serve as a reference for clinical application of this prescription.

Effects of electroacupuncture at "Siguan" points on the expression of colonic 5-hydroxytryptamine and fecal short-chain fatty acids in rats with post-stroke depression / 中国针灸

OBJECTIVE@#To observe the effects of electroacupuncture at "Siguan" points on behavior, colonic 5-hydroxytryptamine (5-HT) and fecal short-chain fatty acids (SCFAs) in rats with post-stroke depression (PSD), and explore the effect mechanism of electroacupuncture at Siguan points on PSD.@*METHODS@#Fifty SD rats were randomly divided into a sham-operation group, a stroke group, a PSD group, a drug group and an electroacupuncture group, with 10 rats in each one. The stroke model was established by middle cerebral artery occlusion (MCAO) method in the stroke group; except for the sham-operation group, the rats in the other groups were intervened with MCAO combined with solitary and chronic unpredictable mild stress (CUMS) to establish PSD model. In the electroacupuncture group, electroacupuncture was delivered at "Hegu" (LI 4) and "Taichong" (LR 3), with disperse-dense wave, 2 Hz/10 Hz in frequency, for 30 min in each intervention, once daily, for consecutive 21 days. Simultaneously, distilled water (0.01 L•kg-1•d-1) was administrated intragastrically. Fluoxetine solution (2.33 mg•kg-1•d-1) was given by gavage , once a day and for 21 days in the drug group. The same procedure of fixation and gavage with distilled water were adopted in the sham-operation group, the stroke group and the PSD group. Separately, before stroke modeling, after PSD modeling and after 21-day intervention, the consumption of sugar water and the scores of horizontal movement and vertical movement in open-field test were observed. After 21-day intervention, the content of colonic 5-HT was detected by immunohistochemical method, and that of fecal SCFAs was determined by gas chromatography mass spectrometry.@*RESULTS@#After PSD modeling, compared with the stroke group, the sugar water consumption, the horizontal movement scores and vertical movement scores of the open-field test were all reduced in the PSD group, the drug group and the electroacupuncture group (P<0.05). After 21-day intervention, the sugar water consumption and the scores of horizontal movement and vertical movement of the open-field test were increased in the drug group and the electroacupuncture group (P<0.05) when compared with the PSD group; and the horizontal movement score in the electroacupuncture group was lower than that of the drug group (P<0.05). Compared with the sham-operation group, the contents of total fecal SCFAs and acetic acid were lower in the stroke group (P<0.05), and the contents of colonic 5-HT and total fecal SCFAs, acetic acid, propionic acid and butyric acid were reduced in the PSD group (P<0.05). In comparison with the PSD group, the contents of colonic 5-HT and total fecal SCFAs, acetic acid and propionic acid were increased in the drug group and the electroacupuncture group (P<0.05); and the content of colonic 5-HT in the electroacupuncture group was lower than that of the drug group (P<0.05). The level of colonic 5-HT was positively correlated with the contents of total fecal SCFAs and propionic acid (r=0.424, P=0.005; r=0.427, P=0.004).@*CONCLUSION@#Electroacupuncture at "Siguan" points can relieve the depression-like behavior of PSD rats, and its underlying mechanism may be related to the regulation of fecal SCFAs, which affects the release of colonic 5-HT.

Short-chain fatty acids ameliorate spinal cord injury recovery by regulating the balance of regulatory T cells and effector IL-17+ γδ T cells / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

Spinal cord injury (SCI) causes motor, sensory, and autonomic dysfunctions. The gut microbiome has an important role in SCI, while short-chain fatty acids (SCFAs) are one of the main bioactive mediators of microbiota. In the present study, we explored the effects of oral administration of exogenous SCFAs on the recovery of locomotor function and tissue repair in SCI. Allen's method was utilized to establish an SCI model in Sprague-Dawley (SD) rats. The animals received water containing a mixture of 150 mmol/L SCFAs after SCI. After 21 d of treatment, the Basso, Beattie, and Bresnahan (BBB) score increased, the regularity index improved, and the base of support (BOS) value declined. Spinal cord tissue inflammatory infiltration was alleviated, the spinal cord necrosis cavity was reduced, and the numbers of motor neurons and Nissl bodies were elevated. Enzyme-linked immunosorbent assay (ELISA), real-time quantitative polymerase chain reaction (qPCR), and immunohistochemistry assay revealed that the expression of interleukin (IL)‍-10 increased and that of IL-17 decreased in the spinal cord. SCFAs promoted gut homeostasis, induced intestinal T cells to shift toward an anti-inflammatory phenotype, and promoted regulatory T (Treg) cells to secrete IL-10, affecting Treg cells and IL-17+ γδ T cells in the spinal cord. Furthermore, we observed that Treg cells migrated from the gut to the spinal cord region after SCI. The above findings confirm that SCFAs can regulate Treg cells in the gut and affect the balance of Treg and IL-17+ γδ T cells in the spinal cord, which inhibits the inflammatory response and promotes the motor function in SCI rats. Our findings suggest that there is a relationship among gut, spinal cord, and immune cells, and the "gut-spinal cord-immune" axis may be one of the mechanisms regulating neural repair after SCI.

Effect of Zuogui Jiangtang Tongmai Prescription on SCFAs/GPR43/GLP-1/GLP-1R Signaling Pathway in Rats with Diabetes Mellitus Complicated with Cerebral Infarction / 中国实验方剂学杂志

ObjectiveTo explore the potential mechanism of Zuogui Jiangtang Tongmai prescription （ZJT） in the treatment of diabetes mellitus complicated with cerebral infarction （DM-CI） in rats based on the short-chain fatty acids （SCFAs）/G protein-coupled receptor 43 （GPR43）/glucagon-like peptide-1 （GLP-1）/GLP-1 receptor （GLP-1R） signaling pathway. MethodSixty SD rats were randomly divided into sham operation group， model group， low- and high-dose ZJT groups （12， 24 g·kg-1）， western medicine group （140 mg·kg-1 pioglitazone metformin tablets + 27 mg·kg-1 enteric-coated aspirin tablets）. Except for the sham operation group， all other groups were fed a high-sugar high-fat diet for 4 weeks and then subjected to intraperitoneal injection of 1% streptozotocin at 35 mg·kg-1 combined with middle cerebral artery occlusion （MCAO） to establish a DM-CI rat model. The corresponding interventions were performed with distilled water， low-dose ZJT， high-dose ZJT， pioglitazone metformin tablets， and enteric-coated aspirin tablets. After surgery， National Institutes of Health Stroke Scale （NIHSS） scoring and triphenyltetrazolium chloride （TTC） staining to measure the rat's cerebral infarct volume were carried out. Random blood glucose levels were measured， and hematoxylin-eosin （HE） staining was used to observe histopathological changes in rat brain tissues. Gas chromatography was employed to detect the content of SCFAs in the cecum contents. Enzyme-linked immunosorbent assay （ELISA） was adopted to measure serum GLP-1 level. Western blot was used to detect the protein expression of GPR43 in rat ileal tissues and GLP-1R in the ischemic brain tissues. ResultCompared with the sham operation group， the model group showed significantly increased NIHSS scores， random blood glucose levels， and cerebral infarct volumes （P<0.01）， and significantly decreased SCFAs content， GLP-1 levels， and GPR43 and GLP-1R protein expression （P<0.01）. Compared with the model group， the high-dose ZJT group and the western medicine group exhibited significantly reduced NIHSS scores， random blood glucose levels， and cerebral infarct volumes （P<0.05， P<0.01）， and significantly increased SCFAs content， GLP-1 levels， and GPR43 and GLP-1R protein expression （P<0.01）. ConclusionZJT can improve glucose metabolism disorder and reduce neurological damage in DM-CI rats， and its mechanism may be related to the increase in SCFAs content and the upregulation of the GPR43/GLP-1/GLP-1R signaling pathway.

Protective effect of Clostridium butyricum on renal tissue in db/db mice and its mechanism / 中华内分泌代谢杂志

Objective:To investigate the effect of Clostridium butyricum on renal tissue of db/db mice and to explore its mechanism. Methods:Fourteen-week-old db/db mice were divided into db/db group( n=10) and db/db+ Cb group( n=7) according to random number table method. Age-matched db/m mice were selected as the normal control group. The db/m and db/db mice were administered 0.9% sodium chloride solution by gavage, while the db/db+ Cb mice were administered an equivalent amount of Clostridium butyricum solution by gavage for 8 weeks. Serum creatinine , fasting blood glucose, urinary albumin to creatinine ratio(ACR) and other biochemical indicators were also detected. HE staining was used to observe the pathological changes of kidney tissue. The expressions of peroxisome proliferators-activated receptor γ coactivator-1α(PGC-1α) mRNA were detected by realtime PCR, while the expressions of nuclear factor-κB(NF-κB), glucagon-like peptide 1 receptor(GLP-1R), and adenosine monophosphate-activated protein kinase(AMPK) in kidney tissue were determined by immunohistochemistry and Western blotting. The levels of intestinal flora, serum and fecal short-chain fatty acids(SCFAs) were measured by 16S rRNA, liquid chromatograph-mass spectrometer, and gas chromatograohy-mass spectrometry respectively. Results:Compared to db/db mice, db/db+ Cb mice showed improvement in general condition after supplementation with Clostridium butyricum. Fasting blood glucose, blood urea nitrogen, albumin-to-creatinine ratio(ACR), blood creatinine, and levels of interleukin-6(IL-6) in kidney tissue were reduced(all P<0.05). The pathology showed various degrees of amelioration of kidney tissue injury in mice. The expression of PGC-1α mRNA increased in kidney tissue( P<0.05). Decreased expression of NF-κB protein, as well as increased expression of GLP-1R and phosphorylated(p-)AMPK/AMPK protein(all P<0.05) were detected in kidney tissues. Clostridium butyricum modulated the composition of the gut microbiota with elevated total SCFAs in blood and feces. Conclusion:Clostridium butyricum increased the expression of GLP-1R in kidney tissue, promoted AMPK phosphorylation, and alleviated renal tissue damage in mice. This suggests that it may be associated with regulating the abundance of SCFA-producing bacterial populations.

Effects of total ginsenosides from Panax ginseng stems and leaves on gut microbiota and short-chain fatty acids metabolism in acute lung injury mice / 中国中药杂志

This study aimed to investigate the biological effects and underlying mechanisms of the total ginsenosides from Panax ginseng stems and leaves on lipopolysaccharide(LPS)-induced acute lung injury(ALI) in mice. Sixty male C57BL/6J mice were randomly divided into a control group, a model group, the total ginsenosides from P. ginseng stems and leaves normal administration group(61.65 mg·kg~(-1)), and low-, medium-, and high-dose total ginsenosides from P. ginseng stems and leaves groups(15.412 5, 30.825, and 61.65 mg·kg~(-1)). Mice were administered for seven continuous days before modeling. Twenty-four hours after modeling, mice were sacrificed to obtain lung tissues and calculate lung wet/dry ratio. The number of inflammatory cells in bronchoalveolar lavage fluid(BALF) was detected. The levels of interleukin-1β(IL-1β), interleukin-6(IL-6), and tumor necrosis factor-α(TNF-α) in BALF were detected. The mRNA expression levels of IL-1β, IL-6, and TNF-α, and the levels of myeloperoxidase(MPO), glutathione peroxidase(GSH-Px), superoxide dismutase(SOD), and malondialdehyde(MDA) in lung tissues were determined. Hematoxylin-eosin(HE) staining was used to observe the pathological changes in lung tissues. The gut microbiota was detected by 16S rRNA sequencing, and gas chromatography-mass spectrometry(GC-MS) was applied to detect the content of short-chain fatty acids(SCFAs) in se-rum. The results showed that the total ginsenosides from P. ginseng stems and leaves could reduce lung index, lung wet/dry ratio, and lung damage in LPS-induced ALI mice, decrease the number of inflammatory cells and levels of inflammatory factors in BALF, inhibit the mRNA expression levels of inflammatory factors and levels of MPO and MDA in lung tissues, and potentiate the activity of GSH-Px and SOD in lung tissues. Furthermore, they could also reverse the gut microbiota disorder, restore the diversity of gut microbiota, increase the relative abundance of Lachnospiraceae and Muribaculaceae, decrease the relative abundance of Prevotellaceae, and enhance the content of SCFAs(acetic acid, propionic acid, and butyric acid) in serum. This study suggested that the total ginsenosides from P. ginseng stems and leaves could improve lung edema, inflammatory response, and oxidative stress in ALI mice by regulating gut microbiota and SCFAs metabolism.

Gut microbiota-derived short-chain fatty acids ameliorate methamphetamine-induced depression- and anxiety-like behaviors in a Sigmar-1 receptor-dependent manner

Methamphetamine (Meth) abuse can cause serious mental disorders, including anxiety and depression. The gut microbiota is a crucial contributor to maintaining host mental health. Here, we aim to investigate if microbiota participate in Meth-induced mental disorders, and the potential mechanisms involved. Here, 15 mg/kg Meth resulted in anxiety- and depression-like behaviors of mice successfully and suppressed the Sigma-1 receptor (SIGMAR1)/BDNF/TRKB pathway in the hippocampus. Meanwhile, Meth impaired gut homeostasis by arousing the Toll-like receptor 4 (TLR4)-related colonic inflammation, disturbing the gut microbiome and reducing the microbiota-derived short-chain fatty acids (SCFAs). Moreover, fecal microbiota from Meth-administrated mice mediated the colonic inflammation and reproduced anxiety- and depression-like behaviors in recipients. Further, SCFAs supplementation optimized Meth-induced microbial dysbiosis, ameliorated colonic inflammation, and repressed anxiety- and depression-like behaviors. Finally, Sigmar1 knockout (Sigmar1-/-) repressed the BDNF/TRKB pathway and produced similar behavioral phenotypes with Meth exposure, and eliminated the anti-anxiety and -depression effects of SCFAs. The activation of SIGMAR1 with fluvoxamine attenuated Meth-induced anxiety- and depression-like behaviors. Our findings indicated that gut microbiota-derived SCFAs could optimize gut homeostasis, and ameliorate Meth-induced mental disorders in a SIGMAR1-dependent manner. This study confirms the crucial role of microbiota in Meth-related mental disorders and provides a potential preemptive therapy.

Gut microbiota controls the development of chronic pancreatitis: A critical role of short-chain fatty acids-producing Gram-positive bacteria

Chronic pancreatitis (CP) is a progressive and irreversible fibroinflammatory disorder, accompanied by pancreatic exocrine insufficiency and dysregulated gut microbiota. Recently, accumulating evidence has supported a correlation between gut dysbiosis and CP development. However, whether gut microbiota dysbiosis contributes to CP pathogenesis remains unclear. Herein, an experimental CP was induced by repeated high-dose caerulein injections. The broad-spectrum antibiotics (ABX) and ABX targeting Gram-positive (G+) or Gram-negative bacteria (G-) were applied to explore the specific roles of these bacteria. Gut dysbiosis was observed in both mice and in CP patients, which was accompanied by a sharply reduced abundance for short-chain fatty acids (SCFAs)-producers, especially G+ bacteria. Broad-spectrum ABX exacerbated the severity of CP, as evidenced by aggravated pancreatic fibrosis and gut dysbiosis, especially the depletion of SCFAs-producing G+ bacteria. Additionally, depletion of SCFAs-producing G+ bacteria rather than G- bacteria intensified CP progression independent of TLR4, which was attenuated by supplementation with exogenous SCFAs. Finally, SCFAs modulated pancreatic fibrosis through inhibition of macrophage infiltration and M2 phenotype switching. The study supports a critical role for SCFAs-producing G+ bacteria in CP. Therefore, modulation of dietary-derived SCFAs or G+ SCFAs-producing bacteria may be considered a novel interventive approach for the management of CP.

Stoichiometric models for prediction of enteric methane production

This study aimed to empirically evaluate the adjustment quality of two stoichiometric models of methane production from diets that used different rumen fermentation modulators. We used the models proposed by Moss et al. (2000) and Blümmel et al. (1997). The data set consisted of 169 observations of in vitro methane production and volatile fatty acids (acetate, propionate, and butyrate) from dissertations, theses, and scientific articles. The model's adequacy evaluation was only possible through combination of several statistical analyzes. The models were unable to predict the enteric methane precisely and accurately. Despite this, the model proposed by Moss et al. (2000) showed a better fit based on the mean bias (% of observed, MB), MEF, RMSEP, Cb and CCC measures compared to the model proposed by Blümmel et al. (1997). However, both models presented strong evidence against the general hypothesis H0: a = 0 & b = 1. Thus, the model proposed by MOSS et al. (2000) was more efficient, whereas the model by Blümmel et al. (1997) showed a better fit for diets with high availability of H2.

Wang's Yijing Decoction Combined with Conventional Therapy： Performance in Treating Polycystic Ovary Syndrome with Kidney Deficiency and Phlegm-dampness Syndrome and Regulating Effect on Intestine-brain Axis / 中国实验方剂学杂志

ObjectiveTo observe the therapeutic effect of Wang's Yijing decoction combined with conventional therapy on the treatment of polycystic ovary syndrome （PCOS） with kidney deficiency and phlegm-dampness syndrome and its regulating effect on the intestine-brain axis. MethodThe 132 patients from the gynecological clinic of Shanxi Bethune Hospital were randomly assigned into a control group and an observation group， with 66 patients in each group. The patients in the control group were treated with drospirenone and ethinylestradiol tablets and metformin tablets， and those in the observation group were administrated with Wang's Yijing decoction on the basis of the therapy in the control group. The treatment in both groups lasted for 3 menstrual cycles. The changes in menstrual blood volume， color， and texture， as well as that in the menstrual cycle before and after treatment were scored. Further， the Rosenfield， hirsutism， and kidney deficiency and phlegm-dampness syndrome were scored before and after treatment. Pelvic ultrasound was performed before and after treatment to compare the bilateral ovarian volume. The levels of anti-mullerian hormone （AMH）， estradiol （E2）， luteinizing hormone （LH）， follicle-stimulating hormone （FSH）， testosterone （T）， dihydrotestosterone （DHT）， and sex hormone-binding globulin （SHBG） were measured before and after treatment， and the free androgen index （FAI） was calculated. After the fasting insulin and fasting blood glucose were examined before and after treatment， the homeostatic model assessment of insulin resistance （HOMA-IR） was calculated. The levels of ghrelin， glucagon-like peptide-1 （GLP-1）， peptide tyrosine-tyrosine （PYY） in serum and short-chain fatty acids （SCFAs） in fresh stool were measured before and after treatment. ResultThe treatments in both groups lowered the scores of irregular menstruation， Rosenfield， hirsutism， and kidney deficiency and phlegm-dampness syndrome （P<0.01）， and the scores in the observation group were lower than those in the control group （P<0.01）. After treatment， the T， DHT， FAI， AMH， E2， LH， and FSH levels lowered （P<0.01）， while the SHBG level elevated （P<0.01）. In addition， the AMH， E2， LH， T， DHT， and FAI in the observation group were lower than those in control group， while the SHBG level presented an opposite trend （P<0.01）. After treatment， the bilateral ovarian volume and HOMA-IR of the two groups decreased （P<0.01）， and were lower in the observation group than in the control group （P<0.05， P<0.01）. The treatments in both groups elevated the levels of ghrelin， GLP-1， PYY， and SCFAs （P<0.01）， which were higher in the observation group than in the control group （P<0.01）. After treatment， the recovery rate in the observation group was 65.57% （40/61）， which was higher than 44.83% （26/58） in the control group （χ2=5.180， P<0.05）. ConclusionWang's Yijing decoction combined with conventional western medicine treatment can regulate the intestine-brain axis， endocrine and metabolic disorders， and sex hormones， adjust the menstrual cycle， and alleviate clinical symptoms， demonstrating good clinical effect for the PCOS patients with kidney deficiency and phlegm dampness syndrome.

Interactions between gut microbiota and berberine,a necessary procedure to understand the mechanisms of berberine / 药物分析学报

Berberine(BBR),an isoquinoline alkaloid,has been found in many plants,such as Coptis chinensis Franch and Phellodendron chinense Schneid.Although BBR has a wide spectrum of pharmacological effects,its oral bioavailability is extremely low.In recent years,gut microbiota has emerged as a cynosure to un-derstand the mechanisms of action of herbal compounds.Numerous studies have demonstrated that due to its low bioavailability,BBR can interact with the gut microbiota,thereby exhibiting altered pharma-cological effects.However,no systematic and comprehensive review has summarized these interactions and their corresponding influences on pharmacological effects.Here,we describe the direct interactive relationships between BBR and gut microbiota,including regulation of gut microbiota composition and metabolism by BBR and metabolization of BBR by gut microbiota.In addition,the complex interactions between gut microbiota and BBR as well as the side effects and personalized use of BBR are discussed.Furthermore,we provide our viewpoint on future research directions regarding BBR and gut microbiota.This review not only helps to explain the mechanisms underlying BBR activity but also provides support for the rational use of BBR in clinical practice.

Progress of Resistant Starch Diet Therapy in Treatment of Inflammatory Bowel Disease / 胃肠病学

As a disease that requires long-term treatment, the safety of treatment is particularly important in the treatment of inflammatory bowel disease (IBD). Numerous studies have shown that diet can alter the intestinal barrier, IBD susceptibility gene expression, immune function, and microbial metabolites by influencing the balance of gut microbes. Diet is therefore one of the key environmental factors that affect the symptoms and recurrence of IBD. The resistant starch diet can increase the viscosity of feces, promote the proliferation of colon symbiotic bacteria and generate a large number of short-chain fatty acids, which is highly correlated with the course of IBD. This article reviewed the progress of resistant starch in treatment of IBD.

Progress in Research on Regulatory Mechanism of Prebiotics in Inflammatory Bowel Disease / 胃肠病学

Inflammatory bowel disease (IBD) is a non⁃specific chronic inflammatory disease of the intestine, and its pathogenesis is not yet been fully elucidated. At present, it is generally believed that gut microbiota plays a key role in the pathogenesis of IBD. Prebiotics are non⁃digestible food ingredients that can regulate the gut microbiota. Recently, more and more studies support the beneficial effect of prebiotics in IBD. Some prebiotics of dietary supplements can be used as fermentable substrates to promote the growth and metabolic activity of intestinal beneficial bacteria and increase the production of short ⁃ chain fatty acids, thereby exerting anti ⁃ inflammatory effects. This article reviewed the progress in research on the protective mechanism of prebiotics in IBD from the perspective of traditional and emerging prebiotics and providing a theoretical basis for its application in IBD adjuvant therapy.

Research progress of short-chain fatty acids in alleviating organ ischemia-reperfusion injury / 中国临床药理学与治疗学

Short-chain fatty acids (SCFAs) are organic acids with no more than 6 carbon atoms produced during the anaerobic fermentation of dietary fiber in the intestinal tract, which can regulate intestinal flora, repair intestinal mucosal barrier, and reduce intestinal injury.Ischemia-reperfusion injury (IRI) is the main cause of various diseases, and the pathological mechanisms involved are intricate, among which inflammation, oxidative stress, apoptosis and autophagy are the most common. According to current studies, SCFAs can affect the occurrence and development of IRI in various organs by regulating different cell signal transduction. In this paper, the role and mechanism of SCFAs in alleviating tissue and organ ischemia-reperfusion injury were preliminarily summarized, providing theoretical reference for clinical prevention and treatment of IRI.

The effect and mechanism of short-chain fatty acid regulate tacrolimus-related hyperglycemia in mice / 中华泌尿外科杂志

Objective:To investigate the effect and mechanism of short-chain fatty acids (SCFAs) on the side-effect of tacrolimus on blood glucose.Methods:The C57BL/6 mice were treated with tacrolimus orally (10 mg/kg, tacrolimus group), tacrolimus plus 150 mmol/L sodium butyrate and isovalerate mixed solution (SCFAs group), broad-spectrum antibiotics (antibiotic group), and tacrolimus plus broad-spectrum antibiotics (tac&abx group). After 8 weeks intervention, the fasting blood glucose (FBG), oral glucose tolerance test (OGTT), hemoglobin A1C (HbA1c) were tested as indicators of glucose metabolism, and the gut microbiota, SCFAs concentration in the ileocecal, serum glucagon-like peptide-1 (GLP-1), fasting serum insulin, and GLP-1 expression in intestinal mucosa were performed for intestinal-glucose metabolism mechanism.Results:The FBG and HbA1c were significantly increased in tacrolimus group[(7.31±0.97)mmol/L, (8.34±1.12)%] than control group [(5.23±0.30)mmol/L, (4.32±0.80)%, all P<0.05], which remained normal in antibiotic group [(4.92±0.31)mmol/L, (5.61±0.98)%)], tac&abx group[(5.95±0.37)mmol/L, (4.56±0.26)%] and SCFAs groups [(5.87±0.68)mmol/L, (5.07±1.79)%]. The OGTT in the tacrolimus group showed glucose tolerance impairment, while other groups remained normal. The ileocecal butyric acid and isovaleric acid concentrations in the tacrolimus group were (722.3±262.2) μg/g and (10.0±5.1)μg/g, lower than the control group[ (1 321.3±165.5) μg/g, (19.7±3.6)μg/g, P<0.05]. The above acids in the SCFAs group remained normal as in the control group [(1 375.7±451.6) μg/g, (24.5±11.5)μg/g)]. The fasting serum insulin in the tacrolimus group decreased significantly to (3.2 ± 0.6)mIU/L, compared with control[ (4.4±0.9) mIU/L]and SCFAs groups [(7.0±1.1) mIU/L]. The GLP-1 test indicated a significant decrease in the tacrolimus group[ (4.7±2.9)pg/ml, P<0.05] compared with the SCFAs group and control group [(42.5±19.9) pg/ml, (33.1±9.1) pg/ml]. Conclusions:Tacrolimus affects glucose metabolism through the SCFAs-associated GLP-1 pathway in the intestine, and oral supplementation with mixed SCFAs provides a new insight for the prevention and treatment of tacrolimus-induced hyperglycemia in transplant recipients.

Research progress of microbe gut brain axis / 中国综合临床

The emergence of gut microbes has become one of the key regulatory factors of gut brain function, and has made people realize the importance of microbe gut brain axis.The gut microbiota and brain are interconnected through immune system, tryptophan metabolism, vagus nerve and endocrine system.Many factors can affect the composition of gut microbiota, including infection, mode of delivery, use of antibiotics, stress, and host genetics.Recent studies have shown that gut microbiota may be associated with many diseases, including autism, irritable bowel syndrome and so on.Future research will focus on understanding the underlying mechanisms of the microbial gut brain axis and attempt to elucidate microbial based intervention and treatment strategies for neuropsychiatric diseases.