Electroacupuncture protects the intestinal mucosal barrier in diarrhea-predominant Irritable Bowel Syndrome rats by regulating the MCs/Tryptase/PAR-2/MLCK pathway.

OBJECTIVE: The pathogenesis of diarrhea-predominant irritable bowel syndrome (IBS-D) is related to damage to the intestinal mucosal barrier function. Based on the Mast cell (MC)/Tryptase/Protease-activated receptor-2 (PAR-2)/Myosin light chain kinase (MLCK) pathway, this study explored the effect of electroacupuncture (EA) on IBS-D rats and its possible mechanism of protecting the intestinal mucosal barrier. METHODS: The IBS-D rat model was established by mother-offspring separation, acetic acid enema, and chronic restraint stress. The efficacy of EA on IBS-D rats was evaluated by observing the rate of loose stool (LSP) and the minimum volume threshold of abdominal withdrawal reflex (AWR) in rats. Mast cells and the ultrastructure of intestinal mucosa were observed by H&E staining, toluidine blue staining, and transmission electron microscopy. The expression levels of Tryptase, PAR-2, MLCK, zonula occludens-1 (ZO-1), and Occludin in rats were detected by ELISA, qRT-PCR, and western blot. RESULTS: After 7 days of intervention, compared to the IBS-D group, the loose stool rates of rats in IBS-D + EA group and IBS-D + ketotifen group were decreased (P < 0.01), the minimum volume thresholds of AWR were improved (P < 0.01), the inflammation of colon tissue decreased, the number of MCs were decreased (P < 0.01), the expression of Tryptase, PAR-2, and MLCK were lowered (P < 0.01, P < 0.05), and the expression of ZO-1 and Occludin were enhanced (P < 0.01, P < 0.05). Compared to the EA group, there was no significant difference in each index between the ketotifen groups (P > 0.05). CONCLUSION: EA has a good therapeutic effect on IBS-D rats. Regulating the MCs/Tryptase/PAR-2/MLCK pathway may be a mechanism to protect the intestinal mucosal barrier.

Moxibustion ameliorates visceral hypersensitivity by regulating hypothalamus-spinal cord-colon axis in rats with irritable bowel syndrome with diarrhea. / 基于下丘脑-脊髓-ç»“è‚ è½´æŽ¢è®¨è‰¾ç¸æ”¹å–„è ¹æ³»åž‹è‚ æ˜“æ¿€ç»¼åˆå¾å¤§é¼ å† è„é«˜æ•æ„Ÿçš„ä½œç”¨æœºåˆ¶.

OBJECTIVES: To observe the effect of moxibustion intervention on the hypothalamus-spinal cord-colon axis of rats with irritable bowel syndrome with diarrhea (IBS-D) and explore the mechanism of moxibustion in improving visceral hypersensitivity in rats with IBS-D. METHODS: A total of 36 SD rats were randomly divided into normal, model, and moxibustion groups, with 12 rats in each group. The IBS-D model was established by maternal separation + acetic acid stimulation + chronic restraint. Rats of the moxibustion group received bilateral moxibustion on "Tianshu" (ST25) and "Shangjuxu" (ST37) for 15 min, once a day for 7 consecutive days. The body weight, loose stool rate, and minimum threshold volume of abdominal withdrawal reflex (AWR) were measured before and after moxibustion intervention, respectively. The histopathological changes in the colon tissue were observed after HE staining. The number of colonic mucosal mast cells (MCs) was measured by toluidine blue staining. The activation of MCs was determined by tryptase positive expression level and examined by immunohistochemical staining. The content, protein and mRNA expression levels and positive expression levels of corticotropin releasing factor (CRF), substance P (SP), and calcitonin gene-related peptide (CGRP) in the hypothalamus, spinal cord and colon tissues were measured by ELISA, Western blot, real-time fluorescent quantitative PCR and immunofluorescence staining, respectively. RESULTS: Compared with the normal group, the loose stool rate was increased (P<0.01)；the body weight and minimum threshold volume of AWR were decreased (P<0.01)；the inflammatory infiltration of colon tissues was obvious；the number of MCs and positive expression level of tryptase in the colon tissue were increased (P<0.01)；the contents, positive expression le-vels, protein and mRNA expression levels of CRF, SP and CGRP in the hypothalamus, spinal cord and colon tissues were increased (P<0.01, P<0.05) in the model group. After the intervention, compared with the model group, all these indicators showed opposite trends (P<0.01, P<0.05) in the moxibustion group. CONCLUSIONS: Moxibustion can improve visceral hypersensitivity in rats with IBS-D, and its mechanism may be related to regulating the hypothalamic-spinal-colon axis to reduce the release of CRF, SP and CGRP, and thus to inhibite MC in colon tissue.

[Moxibustion relieves colonic inflammation by up-regulating expression of miR-345-3p/miR-216a-5p and down-regulating NF-κB p65 in colonic tissue of rats with diarrhea-predominant irritable bowel syndrome].

OBJECTIVE: To observe the effect of moxibustion on the expression of miR-345-3p, miR-216a-5p and nuclear factor-κB p65(NF-κB p65) in colonic tissue of rats with diarrhea-predominant irritable bowel syndrome (IBS-D), so as to explore its anti-inflammatory mechanism in relieving IBS-D. METHODS: SD rats were randomly divided into normal control (n=12), model (n=12), moxibustion (n=12) and ammonium pyrrolidine dithiocarbamate (PDTC,n=12) groups. The IBS-D model was established by neonatal mother-child separation combined with acetic acid enema stimulation and chronic binding methods. The rats in the moxibustion group received moxibustion stimulation of "Tianshu"(ST25) and "Shangjuxu"(ST37) for 20 min, once a day, for 7 days, and those of the PDTC group received intraperitoneal injection of PDTC (50 mg·kg-1·d-1) once daily for 7 days. After the intervention, the body weight, loose stool rate and the minimum volume threshold of abdominal withdrawal reflex (AWR) were observed, and histopathological changes of colonic mucosa were observed by HE staining. The contents of interleukin-1ß (IL-1ß), interleukin-4 (IL-4), interleukin-6 (IL-6) and tumor necrosis factor α (TNF- α) in serum were measured by ELISA. The expression of miR-345-3p, miR-216a-5p and NF-κB p65 mRNA in the colon tissue were detected by quantitative real-time PCR, and the immunoactivities of IL-1ß, IL-6, TNF-α and NF-κB p65 in the colon tissue were determined by immunofluorescence histochemistry. RESULTS: Compared with the normal control group, the loose stool rate, contents of IL-1ß, IL-6 and TNF-α, experssion of NF-κB p65 mRNA and the immunoactivities of IL-1ß, IL-6, TNF-α and NF-κB p65 were significantly increased (P<0.01), whereas the body weight, minimum volume threshold of AWR, content of IL-4, and the relative expression of miR-345-3p and miR-216a-5p were remarkably decreased in the model group (P<0.01). In comparison with the model group, the loose stool rate, contents of IL-1ß, IL-6, TNF-α, expression of NF-κB p65 mRNA and the immunoactivities of IL-1ß, IL-6, TNF-α and NF-κB p65 were considerably down-regulated (P<0.01), while the content of IL-4 and the relative expressions of miR-345-3p and miR-216a-5p were obviously up-regulated in both moxibustion and PDTC groups (P<0.01, P<0.05). The content of IL-6 in serum was significantly lower in the PDTC group than in the moxibustion group (P<0.01). CONCLUSION: Moxibustion can reduce the level of intestinal inflammation and visceral hypersensitivity in IBS-D rats, which may be related to its functions in increasing the expression levels of miR-345-3p and miR-216a-5p and in inhibiting the expression of NF-κB p65, thus reducing the levels of inflammatory factors.

[Effect of moxibustion on immune function homeostasis in rats with diarrhea irritable bowel syndrome based on SCF/c-kit signaling pathway].

OBJECTIVE: To observe the effects of moxibustion on the stem cell factor (SCF)/tyrosine kinase receptor (c-kit) signaling pathway and immune function in rats with diarrhea irritable bowel syndrome (IBS-D), and to explore the mechanism of moxibustion for IBS-D. METHODS: Among 52 young rats born from 6 healthy pregnant SPF rats, 12 rats were randomly selected into the normal group, and the remaining 40 rats were treated with the three-factor combination method of maternal separation, acetic acid enema and chronic restraint stress to establish the IBS-D rat model. Thirty-six rats with successful IBS-D model were randomly divided into a model group, a moxibustion group, and a medication group, 12 rats in each group. The rats in the moxibustion group were treated with suspension moxibustion at "Tianshu" (ST 25) and "Shangjuxu" (ST 37); the rats in the medication group were treated with intragastric administration of rifaximin suspension (150 mg/kg). All the treatments were given once a day for 7 consecutive days. The body mass, loose stool rate (LSR), the minimum volume threshold when abdominal withdrawal reflex (AWR) scored 3 were measured before acetic acid enema (35 days old), after modeling (45 days old), and after intervention (53 days old). After intervention (53 days old), HE staining was used to observe the morphology of colon tissue, and spleen and thymus coefficients were measured; ELISA method was used to detect serum inflammatory factors (tumor necrosis factor a [TNF-a], interleukin [IL]-10, IL-8), T-lymphocyte subsets (CD+4, CD+8, CD+45), value of CD+4/CD+8 and immune globulin (IgA, IgG, IgM); real-time PCR method and Western blot method was used to detect the expression of SCF, c-kit mRNA and protein in colon tissue; immunofluorescence staining method were used to detect positive expression of SCF and c-kit. RESULTS: After intervention, compared with the normal group, in the model group, the body mass and the minimum volume threshold when AWR scored 3 were decreased (P<0.01), LSR, spleen and thymus coefficients, serum levels of TNF-α, IL-8, CD+4, CD+45, CD+4/CD+8, IgA, IgG, IgM were increased (P<0.01), serum IL-10 level and protein and mRNA expression of SCF and c-kit in colon tissue were decreased (P<0.01), and the positive expression of SCF and c-kit was decreased (P<0.01). Compared with the model group, in the moxibustion group and the medication group, the body mass and the minimum volume threshold when AWR scored 3 were increased (P<0.01, P<0.05), LSR, spleen and thymus coefficients, serum levels of TNF-α, IL-8, CD+4, CD+8, CD+45, CD+4/CD+8, IgA, IgG, IgM were decreased (P<0.01, P<0.05), serum IL-10 level and protein and mRNA expression of SCF and c-kit in colon tissue were increased (P<0.01), and the positive expression of SCF and c-kit was increased (P<0.01). Compared with the medication group, in the moxibustion group, the level of serum CD+4 was decreased (P<0.05), the value of CD+4/CD+8 was increased (P<0.01), and there was no significant difference in other indexes (P>0.05). The expression of SCF and c-kit mRNA was positively correlated with the minimum volume threshold when AWR scored 3 and IL-10 (P<0.01), and negatively correlated with remaining indexes (P<0.01, P<0.05). CONCLUSION: Moxibustion could reduce visceral hypersensitivity, improve symptoms of abdominal pain and diarrhea in IBS-D rats, and its mechanism may be related to up-regulation of the expression of SCF/c-kit signaling pathway and improvement of IBS-D immune function.

The Effects of Patchouli Alcohol on Diarrhea-Predominant Irritable Bowel Syndrome are Correlated with Phenotypic Plasticity in Myenteric Neurons and the Targeted Regulation of Myosin Va.

Patchouli alcohol (PA) has been widely used for the treatment of diarrhea-predominant irritable bowel syndrome (IBS-D) in traditional Chinese medicine, and the related mechanism remains to be fully understood. Our previous study has indicated that PA significantly reduced visceral sensitivity and defecation area in IBS-D rats. In this study, we prepared an IBS-D rat model and observed the dynamic intestinal motility and colonic longitudinal muscle and myenteric plexus (LMMP) neurons, as well as their subtypes at D14, D21, and D28. After PA administration, we observed the effects on the changes in intestinal motility, colonic LMMP neurons, and LMMP Myosin Va in IBS-D rats and their co-localization with inhibitory neurotransmitter-related proteins. The results indicated that PA treatment could alleviate IBS-D symptoms, regulate the abnormal expression of LMMP neurons, increase Myosin Va expression, up-regulate co-localization levels of Myosin Va with neuronal nitric oxide synthase (nNOS), and promote co-localization levels of Myosin Va with vasoactive intestinal polypeptide (VIP). In conclusion, this study demonstrated the neuropathic alterations in the colon of chronic restraint stress-induced IBS-D rat model. PA reversed the neuropathological alteration by affecting the transport process of nNOS and VIP vesicles via Myosin Va and the function of LMMP inhibitory neurons, and these effects were related to the mechanism of enteric nervous system (ENS) remodeling.

[Anti-inflammation effect of moxibustion for rats with diarrhea-predominant irritable bowel syndrome based on multiple miRNAs regulating NF-κB signal pathway].

OBJECTIVE: To observe the effect of moxibustion on the regulation of nuclear factor-kappa B (NF-κB) and inflammatory factors by multiple microRNAs (miRNAs) in rats with diarrhea-predominant irritable bowel syndrome (IBS-D), and to explore the anti-inflammatory mechanism of moxibustion on IBS-D. METHODS: Twelve of 52 newborn rats were randomly selected into a normal group. The remaining rats were made into IBS-D model. A total of 36 rats with successful model were randomly divided into a model group, a medication group and a moxibustion group, 12 rats in each group. The rats in the medication group were intraperitoneally injected with pyrrolidine dithiocarbamate (PDTC). The rats in the moxibustion group were treated with moxibustion at "Tianshu" (ST 25) and "Shangjuxu" (ST 37) for 20 min each time. All the intervention was given once a day for 7 days. Before and after modeling as well as after intervention, the body mass, loose stool rate and the minimum volume threshold of abdominal withdrawal reflex (AWR) were measured. After intervention, the contents of serum tumor necrosis factor α (TNF-α), interleukin (IL)-1ß and IL-8 were detected by ELISA method; the morphology of colon tissues was observed by HE staining, and the expressions of miR-155, miR-125b, miR-29b, miR-31, miR-18a and NF-κB p65 mRNA in colon tissues were detected by real-time PCR. The expressions of NF-κB p65, TNF-α, IL-1ß and IL-8 protein in colon tissues were detected by immunofluorescence. RESULTS: After modeling, the body mass and the minimum volume threshold of AWR in the model group were lower than those in the normal group (P<0.01); the rates of loose stool in the model group were higher than those in the normal group (P<0.01); after intervention, in the model group, the inflammatory infiltration of colon tissues was obvious, and the serum levels of TNF-α, IL-1 ß, IL-8 were higher than those in the normal group (P<0.05); the expression of miR-155, miR-125b, miR-29b, miR-31, miR-18a and NF-κB p65 mRNA in colon tissues was higher than that in the normal group (P<0.05); the protein expression of NF-κB p65, TNF-α, IL-1ß, IL-8 was also higher than that in the normal group (P<0.01). After intervention, the body mass and the minimum volume threshold of AWR in the medication group and the moxibustion group were both higher than those in the model group (P<0.05); the loose stool rate in the medication group and the moxibustion group were lower than those in model group (P<0.05); the inflammatory cells infiltration in the colon tissues was less, the serum levels of TNF-α, IL-1ß and IL-8 as well as the protein expression of NF-κB p65, TNF-α, IL-1ß and IL-8 in the colon tissues in the medication group and the moxibustion group were lower than those in the model group (P<0.05, P<0.01). The expression of miR-125b, miR-31, miR-18a and NF-κB p65 mRNA in the medication group were lower than those in the model group (P<0.05). The expression of miR-155, miR-125b, miR-29b, miR-31, miR-18a and NF-κB p65 mRNA in the moxibustion group were lower than those in the model group (P<0.05). The miR-155, miR-125b, miR-29b, miR-31, miR-18a were positively correlated with NF-κB p65 mRNA (0

Effective Sb(V) removal from aqueous solution using phosphogypsum-modified biochar.

Antimonate is the dominant form of antimony (Sb) in Sb mine water. The treatment of high-Sb mine water essentially reduces the discharge of antimonate oxyanions ([Sb(OH)6]-) in it. Biochar obtained from phosphogypsum-modified anaerobic digested distillers' grain (PADC) can effectively adsorb antimonate from water. In this work, using batch adsorption experiments, mathematical models, and characterization methods, the mechanism of Sb(V) adsorption by PADC was studied. Compared with pristine biochar, PADC biochar showed abundant lamellar and vesicular structures with significant calcium ion loading on the surface. The kinetics data of the adsorption of Sb(V) on the PADC biochar followed the Elovich equation (R2 = 0.992), indicating that heterogeneous adsorption had occurred. The results also showed that intraparticle diffusion played an important role in controlling Sb(V) adsorption by PADC biochar. The Redlich-Peterson model best fit the Sb(V) adsorption isotherm (R2 = 0.997), indicating that the adsorption was a combination of the Langmuir and Freundlich models. The maximum adsorption capacity of PADC biochar for Sb(V) is 8123 mg/kg, which is more than twice that of the pristine biochar (3487 mg/kg) and is sufficient for Sb(V) treatment in most mine water. Fourier transform infrared (FTIR) spectra, X-ray photoelectron spectroscopy (XPS), X-ray diffractometry (XRD), and Transmission electron microscopy with energy dispersive X-ray spectroscopy (TEM-EDS) analyses revealed that the dominant mechanism of Sb(V) removal by PADC biochar was the formation of Ca-O-Sb complexes or amorphous surface precipitation as well as electrostatic adsorption. This work demonstrated the potential of PADC biochar in the treatment of Sb-contaminated mine water.

Therapeutic Effects of Berberine Hydrochloride on Stress-Induced Diarrhea-Predominant Irritable Bowel Syndrome Rats by Inhibiting Neurotransmission in Colonic Smooth Muscle.

The etiology of diarrhea-predominant irritable bowel syndrome (IBS-D) is complicated and closely related to neurotransmission in the gastrointestinal (GI) tract. Developing new strategies for treating this disease is a major challenge for IBS-D research. Berberine hydrochloride (BBH), the derivative of berberine, is a herbal constituent used to treat IBS. Previous studies have shown that BBH has potential anti-inflammatory, antibacterial, analgesic, and antidiarrheal effects and a wide range of biological activities, especially in regulating the release of some neurotransmitters. A modified IBS-D rat model induced by chronic restraint stress was used in all experiments to study the effects of BBH on the GI tract. This study measured the abdominal withdrawal reflex (AWR) response to graded colorectal distention (CRD; 20, 40, 60, and 80 mmHg) and observed the fecal areas of stress-induced IBS-D model. Experiments were conducted using organ bath techniques, which were performed in vitro using strips of colonic longitudinal smooth muscle. Inhibitory and excitatory neurotransmitter agents were added to each organ bath to observe contractile responses on the strips and the treatment effect exerted by BBH. The IBS-D rat model was successfully induced by chronic restraint stress, which resulted in an increased defecation frequency and visceral hypersensitivity similar to that of humans. BBH could reduce 4-h fecal areas and AWR response to CRD in IBS-D. The stress-induced IBS-D model showed upregulated colonic mRNA expression levels of 5-hydroxytryptamine-3A receptor and downregulated expression levels of neuronal nitric oxide synthase. Meanwhile, BBH could reverse this outcome. The responses of substances that regulate the contraction induced by related neurotransmission in the longitudinal smooth muscle of IBS-D colon (including the agonist of acetylcholine, carbachol; NOS inhibitor, L-NAME; and P2Y1 receptor antagonist, MRS2500) can be inhibited by BBH. In summary, BBH promotes defecation frequency and visceral hypersensitivity in IBS-D and exerts inhibitory effects on contractile responses in colonic longitudinal smooth muscle. Thus, BBH may represent a new therapeutic approach for treating IBS-D.

Influence of Orally Administered Borneol on the Expression of Hepatic Transporters in Rats.

BACKGROUND AND OBJECTIVE: Borneol, a traditional Chinese medicine (TCM), is often orally co-administered with other TCM and chemical drugs, but the drug-drug interactions between borneol and the other compounds remains unclear. This work investigates the effect of orally administered borneol on the transcription and expression of hepatic uptake transporters (Ntcp, Oatp2b1, Oatp1a1, Oatp1a4, Oct1, Oct2, Octn2 and Oat2) and efflux transporters (Mdrla, Mrp2, Mrp4 and Mrp5) in rats, aiming to obtain essential information to guide its clinical applications. METHODS: Rats were administered borneol (33, 100 and 300 mg/kg/day, respectively) and vehicle (control) orally via intragastric gavage for 7 consecutive days. The mRNA levels of rat hepatic uptake transporters (Ntcp, Oatp2b1, Oatp1a1, Oatp1a4, Oct1, Oct2, Octn2 and Oat2) and efflux transporters (Mdrla, Mrp2, Mrp4 and Mrp5) were determined using real-time quantitative PCR, while the hepatic Ntcp, Mdrla, Mrp2, Mrp4 and Mrp5 proteins were quantified using western blotting. RESULTS: The oral administration of borneol led to dose-dependent inhibition of mRNA and protein expression of Mrp4 and Mdr1a, dose-independent inhibition of mRNA and protein expression of Mrp2, and inverse dose-dependent inhibition of mRNA and protein expression of Ntcp. No significant effects were observed for mRNA expression of the other transporters tested following borneol administration. CONCLUSIONS: Oral administration of borneol may affect the metabolism of substances that are involved in bile acid enterohepatic circulation and substrates of Ntcp, Mdrla, Mrp2 and Mrp4 transporters.