Investigation of the cell composition and gene expression in the delayed-type hypersensitivity tuberculin skin test

Dear Editor,The tuberculin skin test(TST)reagents have continuously improved,with the ESAT6-CFP10(EC)test having recently been introduced,but are seldom based on the direction of the delayed-type hypersensitivity(DTH)mechanism.Previous studies only partially showed the infiltration and activation of immune cells and the production of cytokines of the skin induration[1,2],and lack the detailed measurements of cell proportions and gene expression in the DTH response.Therefore,in this study,we revealed the comprehensive characteristics of DTH by single-cell RNA sequencing(scRNA-seq)in the guinea pig tuberculosis(TB)model[Experimental Animal Welfare Ethics Committee,Beijing Tuberculosis and Thoracic Tumor Research Institute(2021-064)].

Analysis of T-lymphocyte subtypes of the peripheral blood and skindelayed-type hypersensitivity in patients with hyper-IgE syndrome

Objective: To study the function of ce ll ular immunity in patients with hyper-IgE syndrome (HIE). Methods: T-lymphocyte subtypes of the peripheral blood and cutaneous delayed-typ e hypersensitivity (DTH) response to two recall antigens, tetanus toxoid (TT) an d purified protein derivative(PPD), were measured in five patients with HIE and 15 healthy controls, respectively. Results: The CD4+ cell cou nts in HIE group were significantly lower than those in control group (P<0. 01). In contrast, CD8+ cells were significantly higher than those in the contro l (P<0.01). The induration sizes of DTH response to two recall antigens wer e smaller in HIE group than those in the control group (P<0.01). Co nclusion: There was an immunologic dysfunction of T lymphocytes in the p atients with HIE.

Intermittent Fasting Ameliorates Delayed-Type Hypersensitivity in NC/Nga Mice

It is well documented that dietary restriction can prevent many different diseases and extend the life spans of different rodent species. In the previous study, we reported that intermittent fasting (IF) as well as moderate dietary restriction ameliorated the allergic dermatitis in ICR mice. In the present study, we demonstrated the ameliorative effects of IF on allergic dermatitis in NC/Nga mice, a strain known as a model for atopic dermatitis. Interestingly, the total number of CD4+CD8+ double positive thymocyte in mice after IF significantly decreased in comparison to that in mice fed ad libitum. Although it was reported that an immunosuppressive compound inhibited the contact allergic response by inducing the CD4+CD25+ regulatory T-cells, IF did not affect regulatory T cells in the present study. These results suggested that CD4+CD8+ double positive thymocytes play an important role in the regulation of allergy by IF in NC/Nga mice.

Evaluation of Recombinant <i>Mycobacterium tuberculosis</i>Antigens MPT64, CFP10, and ESAT6 for Delayed-Type Hypersensitivity Responses in Guinea Pigs

The tuberculin Purified Protein Derivative (PPD) skin test is widely used;however, the results are often inaccurate. Positive results can be observed in patients with active tuberculosis (TB) as well as in BCG-vaccinated persons and individuals who are infected with mycobacteria but have not developed the disease. MPT64, an antigen secreted from actively growing Mycobacterium tuberculosis and some strains of M. bovis BCG such as BCG Tokyo and BCG Russia, is immunogenic and elicits delayed-type hypersensitivity (DTH) in guinea pigs and humans. This antigen has been used to develop a new skin test for the diagnosis of active TB infection. Two of the antigens encoded by the M. tuberculosis-specific region of difference 1 (RD1, deleted in M. bovis BCG strains), CFP10 (culture filtrate protein 10) and ESAT6 (early secreted antigenic target-6), also induce M. tuberculosis-specific DTH responses. The aim of this study was to investigate the DTH responses in guinea pigs infected with M. tuberculosis or M. bovis BCG Tokyo elicited by three purified recombinant proteins (rMPT64, rCFP10 and rESAT6) compared to those elicited by PPD. In this study genes encoding MPT64, CFP10, and ESAT6 were cloned and expressed as recombinant proteins with the addition of a C-terminal His6 tag for ease of purification by Immobilized Metal ion Affinity Chromatography (IMAC). The recombinant proteins (rMPT64, rCFP10, and rESAT6) were purified to homogeneity and were used to elicit DTH responses in guinea pigs infected with M. tuberculosis or M. bovis BCG Tokyo. The results showed that rMPT64 elicits a DTH response comparable to that of PPD in M. bovis BCG Tokyo-vaccinated animals. However, M. tuberculosis-infected animals show less reactivity to rMPT64 than they do to PPD. Although single rCFP10 or rESAT6 did not readily elicit a DTH response in M. tuberculosis-infected animals, combining these antigens with rMPT64 led to an increased DTH response, thus enabling the detection of TB infection.

The Beneficial Effect of 3-Month-Induction Therapy with Corticosteroids and Mycophenolate Mofetil Followed by Maintenance Therapy with Yearly Rituximab Infusions as Sole Maintenance Therapy in Cryptogenic Chronic Hypersensitivity Pneumonitis

Background: The available data on cryptogenic chronic hypersensitivity pneumonitis (ccHP) indicate an inherited predisposition to disease with triggering autoimmune phenomena. Hence, we evaluated prospectively the role of a new autoimmune regimen in treatment of its severe and progressive disease. Patients and Methods: A total of 9 patients were included in the study. They had criteria for ccHP viz. 1) clinical features of cryptogenic progressive restrictive lung disease, 2) high-resolution computed tomographic pulmonary abnormalities, and 3) bronchoalveolar lavage lymphocytosis (>30%). The regimen consisted of an initial induction phase of 3-month Solumedrol 1 g IV daily for 3 days followed by 1 month of Prednisone (P) 60 mg/day to tapered down to discontinuation by 3rd month. They also had received Mycophenolate mofetil (MMF) 1 g twice daily for 3 months. This stage was followed by a maintenance phase of yearly Rituximab infusions (1 g followed by 1 g 2 weeks later). Results: compared to their previous 6 months deterioration;all patients showed significant improvement in their forced vital volume, diffusion capacity for carbon monoxide, 6-minutes-walk after the induction phase (at 3 months) which improved further at 15 months with Rituximab therapy. Conclusion: After 3-month induction therapy with P and MMF;yearly R treatment is a safe, practical and effective long-term therapy for ccHP.

A Selective‑Response Hypersensitive Bio‑Inspired Strain Sensor Enabled by Hysteresis Effect and Parallel Through‑Slits Structures

Flexible strain sensors are promising in sensing minuscule mechanical signals,and thereby widely used in various advanced fields.However,the effective integration of hypersensitivity and highly selective response into one flexible strain sensor remains a huge challenge.Herein,inspired by the hysteresis strategy of the scorpion slit receptor,a bio-inspired flexible strain sensor(BFSS)with parallel through-slit arrays is designed and fabricated.Specifically,BFSS consists of conductive monolayer graphene and viscoelastic styrene–isoprene–styrene block copolymer.Under the synergistic effect of the bio-inspired slit structures and flexible viscoelastic materials,BFSS can achieve both hypersensitivity and highly selective frequency response.Remarkably,the BFSS exhibits a high gage factor of 657.36,and a precise identification of vibration frequencies at a resolution of 0.2 Hz through undergoing different morphological changes to high-frequency vibration and low-frequency vibration.Moreover,the BFSS possesses a wide frequency detection range(103 Hz)and stable durability(1000 cycles).It can sense and recognize vibration signals with different characteristics,including the frequency,amplitude,and waveform.This work,which turns the hysteresis effect into a"treasure,"can provide new design ideas for sensors for potential applications including human–computer interaction and health monitoring of mechanical equipment.

Hypersensitivity Reaction Caused by Intravenous Gadolinium-based MRI Contrast Agents

Objective To present a rare case of skin allergic reaction to gadobutrol,a magnetic resonance imaging(MRI)contrast agent,in a 37-year-old man.Methods The adverse reactions of gadobutrol were analyzed combined with the instructions and related literatures.Results and Conclusion The presence of this patient is consistent with the adverse reactions in the instructions of gadobutrol.The incidence of ADR in gadobutrol is considered to be low,although sometimes patients report a hypersensitivity reaction when undergoing MRI.There are only a few cases of immediate adverse reactions to gadobutrol.However,we should improve the ability of medical staff to use drugs safely and take preventive measures.

Antinociceptive effect of berberine on visceral hypersensitivity in rats

AIM: To assess the protective effect of berberine administration and the role of nitric oxide (NO) in visceral hypersensitivity. METHODS: Fifty male Sprague-Dawley rats were randomly assigned to five groups. An inflammatory bowel disease model was induced in rats by intracolonic instillation of 1 mL 4% acetic acid at 8 cm proximal to the anus for 30 s and restraint stress. After subsidence of inflammation on day 7 of the experiment, the rats were subjected to rectal distension, performed by a balloon (6-Fr, 2 mm external diameter, disposable silicon balloon-urethral catheter for pediatric use) which was rapidly inflated with increasing volumes of prewarmed (37 ℃) water (0.1, 0.2, 0.3, 0.4, 0.6, 0.8 and 1 mL) for 30 s at four-minute intervals, and then the abdominal withdrawal reflex (AWR) and the level of fecal output were measured, respectively. AWR scores either 0, 1, 2, 3 or 4 were obtained by blinded observers. Rats had been pretreated with berberine or aminoguanidine (NO synthetase inhibitor) or berberine + aminoguanidine before measurement. RESULTS: The rats in the placebo group showed a hypersensitive response to rectal distension (2.69 ± 0.08 vs 1.52 ± 0.08, P = 0.000) and defecated more frequently than those in the control group (5.0 ± 0.16 vs 0.44 ± 0.16, P = 0.000). Comparing the berberine with placebo group, the AWR scores were reduced for all distension volumes and were significant at 0.2-1 mL (1.90 ± 0.08 vs 2.69 ± 0.08, P = 0.000), while the numbers of hard pellets, soft pellets, formless stools, and total fecal output in the placebo group were significantly larger than in the berberine group (5.0 ± 0.16 vs 2.56 ± 0.16, P = 0.000). Administration of aminoguanidine or berberine + aminoguanidine before VH score measurement reversed the antinociceptive effect of berberine (2.52 ± 0.08 vs 1.90 ± 0.08, P = 0.000; 2.50 ± 0.08 vs 1.90 ± 0.08, P = 0.000). The numbers of hard pellets, soft pellets, formless stool, and total of fecal output in aminoguanidine group were significantly larger than the corresponding values in control group, berberine group, and berberine + aminoguanidine group (4.81 ± 0.16 vs 0.44 ± 0.16, P = 0.000; 4.81 ± 0.16 vs 2.56 ± 0.16, P = 0.000; 4.81 ± 0.16 vs 3.75 ± 0.16, P = 0.000). The berberine and berberine + aminoguanidine groups showed reduced defecation, but aminoguanidine alone did not reduce defecation (2.56 ± 0.16 vs 4.81 ± 0.16, P = 0.000; 3.75 ± 0.16 vs 4.81 ± 0.16, P = 0.000). CONCLUSION: Berberine had an antinociceptive effect on visceral hypersensitivity, and NO might play a role in this effect.

Comparison of the analgesic effects between electro-acupuncture and moxibustion with visceral hypersensitivity rats in irritable bowel syndrome

AIM To observe whether there are differences in the effects of electro-acupuncture(EA) and moxibustion(Mox) in rats with visceral hypersensitivity. METHODS EA at 1 m A and 3 m A and Mox at 43?℃ and 46?℃ were applied to the Shangjuxu(ST37, bilateral) acupoints in model rats with visceral hypersensitivity. Responses of wide dynamic range neurons in dorsal horns of the spinal cord were observed through the extracellular recordings. Mast cells(MC) activity in the colons of rats were assessed, and 5-hydroxytryptamine(5-HT), 5-hydroxytryptamine 3 receptor(5-HT3R) and 5-HT4Rexpressions in the colons were measured.RESULTS Compared with normal control group, responses of wide dynamic range neurons in the dorsal horn of the spinal cord were increased in the EA at 1 m A and 3 m A groups(1 m A: 0.84 ± 0.74 vs 2.73 ± 0.65, P < 0.001; 3 m A: 1.91 ± 1.48 vs 6.44 ± 1.26, P < 0.001) and Mox at 43?℃ and 46?℃ groups(43?℃: 1.76 ± 0.81 vs 4.14 ± 1.83, P = 0.001; 46?℃: 5.19 ± 2.03 vs 7.91 ± 2.27, P = 0.01). MC degranulation rates and the expression of 5-HT, 5-HT3 R and 5-HT4 R in the colon of Mox 46?℃ group were decreased compared with model group(MC degranulation rates: 0.47 ± 0.56 vs 0.28 ± 0.78, P < 0.001; 5-HT: 1.42 ± 0.65 vs 7.38 ± 1.12, P < 0.001; 5-HT3R: 6.62 ± 0.77 vs 2.86 ± 0.88, P < 0.001; 5-HT4R: 4.62 ± 0.65 vs 2.22 ± 0.97, P < 0.001). CONCLUSION The analgesic effects of Mox at 46?℃ are greater than those of Mox at 43?℃, EA 1 m A and EA 3 m A.

Increased expression of brain-derived neurotrophic factor is correlated with visceral hypersensitivity in patients with diarrheapredominant irritable bowel syndrome

BACKGROUND Visceral hypersensitivity is considered to play a vital role in the pathogenesis of irritable bowel syndrome(IBS). Neurotrophins have drawn much attention in IBS recently. Brain-derived neurotrophic factor(BDNF) was found to mediate visceral hypersensitivity via facilitating sensory nerve growth in pre-clinical studies. We hypothesized that BDNF might play a role in the pathogenesis of diarrhea-predominant IBS(IBS-D).AIM To investigate BDNF levels in IBS-D patients and its role in IBS-D pathophysiology.METHODS Thirty-one IBS-D patients meeting the Rome IV diagnostic criteria and 20 ageand sex-matched healthy controls were recruited. Clinical and psychological assessments were first conducted using standardized questionnaires. Visceral sensitivity to rectal distension was tested using a high-resolution manometry system. Colonoscopic examination was performed and four mucosal pinch biopsies were taken from the rectosigmoid junction. Mucosal BDNF expression and nerve fiber density were analyzed using immunohistochemistry. Mucosal BDNF mRNA levels were quantified by quantitative real-time polymerase chain reaction. Correlations between these parameters were examined.RESULTS The patients had a higher anxiety score [median(interquartile range), 6.0(2.0-10.0) vs 3.0(1.0-4.0), P = 0.003] and visceral sensitivity index score [54.0(44.0-61.0)vs 21.0(17.3-30.0), P < 0.001] than controls. The defecating sensation threshold[60.0(44.0-80.0) vs 80.0(61.0-100.0), P = 0.009], maximum tolerable threshold[103.0(90.0-128.0) vs 182.0(142.5-209.3), P < 0.001] and rectoanal inhibitory reflex threshold [30.0(20.0-30.0) vs 30.0(30.0-47.5), P = 0.032] were significantly lower in IBS-D patients. Intestinal mucosal BDNF protein [3.46 E-2(3.06 E-2-4.44 E-2) vs3.07 E-2(2.91 E-2-3.48 E-2), P = 0.031] and mRNA [1.57(1.31-2.61) vs 1.09(0.74-1.42), P = 0.001] expression and nerve fiber density [4.12 E-2(3.07 E-2-7.46 E-2) vs1.98 E-2(1.21 E-2-4.25 E-2), P = 0.002] were significantly elevated in the patients.Increased BDNF expression was positively correlated with abdominal pain and disease severity and negatively correlated with visceral sensitivity parameters.CONCLUSION Elevated mucosal BDNF may participate in the pathogenesis of IBS-D via facilitating mucosal nerve growth and increasing visceral sensitivity.

Visceral hypersensitivity and electromechanical dysfunction as therapeutic targets in pediatric functional dyspepsia

Functional gastrointestinal disorders(FGID) are common clinical syndromes diagnosed in the absence of biochemical,structural,or metabolic abnormalities. They account for significant morbidity and health care expenditures and are identifiable across variable age,geography,and culture. Etiology of abdominal pain associated FGIDs,including functional dyspepsia(FD),remains incompletely understood,but growing evidence implicates the importance of visceral hypersensitivity and electromechanical dysfunction. This manuscript explores data supporting the role of visceral hypersensitivity and electromechanical dysfunction in FD,with focus on pediatric data when available,and provides a summary of potential therapeutic targets.

Role of nesfatin-1 in a rat model of visceral hypersensitivity

AIM: To explore the role of nesfatin-1 on irritable bowel syndrome (IBS)-like visceral hypersensitivity. METHODS: The animal model of IBS-like visceral hypersensitivity was induced by intracolonic infusion of 0.5% acetic acid (AA) in saline once daily from postnatal days 8-21. Experiments were performed when rats became adults. The visceral sensitivity of rats was evaluated by abdominal withdrawal reflex (AWR) and electromyographic (EMG) activity of the external oblique muscle to graded colorectal distension. The content of nesfatin-1 in serum was determined using enzyme-linked immunosorbent assay. After implantation of an intracerebroventricular (ICV) cannula and two electrodes into the external oblique muscle, model rats were randomly divided into four groups. Animals then received ICV injection of 8 μg of anti-nesfatin-1/ nucleobindin-2 (NUCB2), 50 μg of α-helical cortico-tropin releasing factor (CRF) 9-41 (non-selective CRF receptor antagonist), 50 μg of NBI-27914 (selective CRF1 receptor antagonist) or 5 μL of vehicle. After 1 h of ICV administration, visceral sensitivity of each group was measured again, and comparisons between groups were made. RESULTS: Rats treated with AA showed higher mean AWR scores and EMG activity at all distension pressures compared with controls (P < 0.05). On histopathologic examination, no evidence of inflammation or abnormalities in structure were noted in the colon of either control or AA-treated groups. Myeloperoxidase values were not significantly different between the two groups. The level of nesfatin-1 in serum was significantly higher in the AA-treated group than in the control group (5.34 ± 0.37 ng/mL vs 4.81 ± 0.42 ng/mL, P < 0.01). Compared with rats injected with vehicle, rats which received ICV anti-nesfatin-1/NUCB2, α-helical CRF9-41 or NBI-27914 showed decreased mean AWR scores and EMG activity at all distension pressures (P < 0.05). CONCLUSION: Nesfatin-1 may be associated with IBS-like visceral hypersensitivity, which may be implicated in brain CRF/CRF1 signaling pathways.

Delayed hypersensitivity reaction resulting in maculopapular-type eruption due to entecavir in the treatment of chronic hepatitis B

Several clinical trials have demonstrated the potent antiviral efficacy of entecavir(ETV), and this relatively new nucleoside analogue drug has rapidly become a frequently prescribed therapy for chronic hepatitis B(CHB) worldwide. While the studies have also shown a good overall safety profile for ETV, adverse drug reactions(ADRs) in patients with advanced cirrhosis have been reported and represent a broad spectrum of drug-induced injuries, including lactic acidosis, myalgia, neuropathy, azotemia, hypophosphatemia, muscular weakness, and pancreatitis, as well as immunemediated responses(i.e., allergic reactions). Cutaneous ADRs associated with ETV are very rare, with only two case reports in the publicly available literature; both of these cases were classified as unspecified hypersensitivity allergic(type I) ADR, but neither were reported as pathologically proven or as evaluated by cytokine release analysis. Here, we report the case of a 45-yearold woman who presented with a generalized maculopapular rash after one week of ETV treatment for lamivudine-resistant CHB. The patient reported having experienced a similar skin eruption during a previous three-month regimen of ETV, for which she had selfdiscontinued the medication. Histopathological analysis of a skin biopsy showed acanthotic epidermis with focal parakeratosis and a perivascular lymphocytic infiltrate admixed with interstitial eosinophils in the papillary and reticular dermis, consistent with a diagnosis of drug sensitivity. A lymphocyte stimulation test showed significantly enhanced IL-4, indicating a classification of type Ⅳb delayed hypersensitivity. The patient was switched to an adefovir-lamivudine combination regimen and the skin eruption resolved two weeks after the ETV withdrawal. This case represents the first pathologically and immunologically evidenced ETV-induced delayed type hypersensitivity skin reaction reported to date. Physicians should be aware of the potential, although rare, for cutaneous ADRs associated with ETV treatment.

TLR4 upregulates CBS expression through NF-κB activation in a rat model of irritable bowel syndrome with chronic visceral hypersensitivity

AIM:To investigate the roles of toll-like receptor 4(TLR4) and nuclear factor(NF)-κB on cystathionine βsynthetase(CBS) expression and visceral hypersensitivity in rats.METHODS:This study used 1-7-wk-old male SpragueDawley rats.Western blot analysis was employed to measure the expression of TLR4,NF-kB and the endogenous hydrogen sulfide-producing enzyme CBS in colon dorsal root ganglia(DRG) from control and "irritable bowel syndrome" rats induced by neonatal colonic inflammation(NCI).Colon-specific DRG neurons were labeled with Dil and acutely dissociated to measure excitability with patch-clamp techniques.Immunofluorescence was employed to determine the co-expression of TLR4,NF-kB and CBS in Dil-labeled DRG neurons.RESULTS:NCI significantly upregulated the expression of TLR4 in colon-related DRGs(0.34 ± 0.12 vs 0.72 ±0.02 for the control and NCI groups,respectively,P <0.05).Intrathecal administration of the TLR4-selective inhibitor CLI-095 significantly enhanced the colorectal distention threshold of NCI rats.CLI-095 treatment also markedly reversed the hyperexcitability of colonspecific DRG neurons and reduced the expression of CBS(1.7 ± 0.1 vs 1.1 ± 0.04,p < 0.05) and of the NF-kB subunit p65(0.8 ± 0.1 vs 0.5 ± 0.1,P< 0.05).Furthermore,the NF-KB-selective inhibitor pyrrolidine dithiocarbamate(PDTC) significantly reduced the upregulation of CBS(1.0 ± 0.1 vs 0.6 ± 0.1,P< 0.05)and attenuated visceral hypersensitivity in the NCI rats.In vitro,incubation of cultured DRG neurons with the TLR4 agonist lipopolysaccharide significantly enhanced the expression of p65(control vs 8 h:0.9 ± 0.1 vs1.3 ± 0.1;control vs 12 h:0.9 ± 0.1 vs 1.3 ± 0.1,P< 0.05;control vs 24 h:0.9 ± 0.1 vs 1.6 ± 0.1,P <0.01) and CBS(control vs 12 h:1.0 ± 0.1 vs 2.2 ±0.4;control vs 24 h:1.0 ± 0.1 vs 2.6 ± 0.1,P< 0.05),whereas the inhibition of p65 via pre-incubation with PDTC significantly reversed the upregulation of CBS expression(1.2 ± 0.1 vs 0.6 ± 0.0,P< 0.01).CONCLUSION:Our results suggest that the activation of TLR4 by NCI upregulates CBS expression,which is mediated by the NF-kB signaling pathway,thus contributing to visceral hypersensitivity.

Berberine prevents stress-induced gut inflammation and visceral hypersensitivity and reduces intestinal motility in rats

BACKGROUND Irritable bowel syndrome (IBS) is a common chronic non-organic disease of the digestive system. Berberine (BBR) has been used to treat patients with IBS, but the underlying therapeutic mechanism is little understood. We believe that BBR achieves its therapeutic effect on IBS by preventing stress intestinal inflammation and visceral hypersensitivity and reducing bowel motility. AIM To test the hypothesis that BBR achieves its therapeutic effect on IBS by preventing subclinical inflammation of the intestinal mucosa and reducing visceral hypersensitivity and intestinal motility. METHODS IBS was induced in rats via water avoidance stress (WAS). qRT-PCR and histological analyses were used to evaluate the levels of cytokines and mucosal inflammation, respectively. Modified ELISA and qRT-PCR were used to evaluate the nuclear factor kappa-B (NF-κB) signal transduction pathway. Colorectal distention test, gastrointestinal transit measurement, Western blot, and qRT-PCR were used to analyze visceral sensitivity, intestinal motility, the expression of Ckit (marker of Cajal mesenchymal cells), and the expression of brain derived neurotrophic factor (BDNF) and its receptor TrkB.RESULTS WAS led to mucosal inflammation, visceral hyperalgesia, and high intestinal motility. Oral administration of BBR inhibited the NF-κB signal transduction pathway, reduced the expression of pro-inflammatory cytokines [interleukin (IL)- 1β, IL-6, interferon-γ, and tumor necrosis factor-α], promoted the expression of anti-inflammatory cytokines (IL-10 and transforming growth factor-β), and improved the terminal ileum tissue inflammation. BBR inhibited the expression of BDNF, TrkB, and C-kit in IBS rats, leading to the reduction of intestinal motility and visceral hypersensitivity. The therapeutic effect of BBR at a high dose (100 mg/kg) was superior to than that of the low-dose (25 mg/kg) group. CONCLUSION BBR reduces intestinal mucosal inflammation by inhibiting the intestinal NF-κB signal pathway in the IBS rats. BBR reduces the expression of BDNF, its receptor TrkB, and C-kit. BBR also reduces intestinal motility and visceral sensitivity to achieve its therapeutic effect on IBS.

Preinduced intestinal HSP70 improves visceral hypersensitivity and abnormal intestinal motility in PI-IBS mouse model

Objective:To investigate the impact of the preinduced intestinal heat shock protein 70(HSP70)on the visceral hypersensitivity and abnormal intestinal motility in a post-infectious irritable bowel syndrome(PI-IBS) mouse model.Methods:Eighty-four female C57BL/6 mice were randomly assigned to four groups:control group(n=21) and induction+PI-IBS group(n=21),PI-IBS group(n=21) and induction group(n=21).The mice in PI-IBS group were infected in vivo with trichinella spiralis by oral administration.The visceral hypersensitivity and intestinal motility were evaluated respectively with abdominal withdrawal reflex and colon transportation test.The intestinal HSP70 protein and mRNA level was measured by Western blot and realtime PCR.Meanwhile,the intestinal proinflammatory cytokines IL-10 and TNF-α level was detected by ELISA.Results:Compared with their counterparts in PI-IBS group,the animals in the Induction+PI-IBS group show significantly increased intestinal level of HSP70 and obviously ameliorative clinical tigurcs.including abdominal withdrawal reflex score,intestine transportation time and Bristol scores(P<0.05).Meanwhile,the intestinal post-inflammatory cytokines remarkably changed,including increased IL-10 level and decreased TNF-αlevel(P<0.05).Conclusions:Intestinal IISP70 may play a potential protective role through improving the imbalance between the intestinal post-inflammatory and anti-inflammatory cytokines in PI-IBS.

Altered profiles of fecal metabolites correlate with visceral hypersensitivity and may contribute to symptom severity of diarrhea-predominant irritable bowel syndrome

BACKGROUND Fecal metabolites are associated with gut visceral sensitivity,mucosal immune function and intestinal barrier function,all of which have critical roles in the pathogenesis of irritable bowel syndrome(IBS).However,the metabolic profile and pathophysiology of IBS are still unclear.We hypothesized that altered profiles of fecal metabolites might be involved in the pathogenesis of IBS with predominant diarrhea(IBS-D).AIM To investigate the fecal metabolite composition and the role of metabolites in IBSD pathophysiology.METHODS Thirty IBS-D patients and 15 age-and sex-matched healthy controls(HCs)underwent clinical and psychological assessments,including the IBS Symptom Severity System(IBS-SSS),an Italian modified version of the Bowel Disease Questionnaire,the Bristol Stool Form Scale(BSFS),the Hospital Anxiety and Depression Scale,and the Visceral Sensitivity Index.Visceral sensitivity to rectal distension was tested using high-resolution manometry system by the same investigator.Fecal metabolites,including amino acids and organic acids,were measured by targeted metabolomics approaches.Correlation analyses between these parameters were performed.RESULTS The patients presented with increased stool water content,more psychological symptoms and increased visceral hypersensitivity compared with the controls.In fecal metabolites,His[IBS-D:0.0642(0.0388,0.1484),HC:0.2636(0.0780,0.3966),P=0.012],Ala[IBS-D:0.5095(0.2826,0.9183),HC:1.0118(0.6135,1.4335),P=0.041],Tyr[IBS-D:0.1024(0.0173,0.4527),HC:0.5665(0.2436,1.3447),P=0.018],Phe[IBS-D:0.1511(0.0775,0.3248),HC:0.3967(0.1388,0.7550),P=0.028],and Trp[IBS-D:0.0323(0.0001,0.0826),HC:0.0834(0.0170,0.1759),P=0.046]were decreased in IBS-D patients,but isohexanoate[IBS-D:0.0127(0.0060,0.0246),HC:0.0070(0.0023,0.0106),P=0.028]was significantly increased.Only Tyr was mildly correlated with BSFS scores in all subjects(r=-0.347,P=0.019).A possible potential biomarker panel was identified to correlate with IBS-SSS score(R2 Adjusted=0.693,P<0.001).In this regression model,the levels of Tyr,Val,hexanoate,fumarate,and pyruvate were significantly associated with the symptom severity of IBS-D.Furthermore,visceral sensation,including abdominal pain and visceral hypersensitivity,was correlated with isovalerate,valerate and isohexanoate.CONCLUSION Altered profiles of fecal metabolites may be one of the origins or exacerbating factors of symptoms in IBS-D via increasing visceral sensitivity.

Ulcerative colitis flair induced by mesalamine suppositories hypersensitivity

Mesalamine suppositories have been used widely for the treatment of distal ulcerative colitis and considered to be safer than systemic administration for its limited systemic absorption.However,previous studies have shown that mesalamine suppository occasionally causes severe hypersensitivity reactions including fever,rashes,colitis exacerbation and acute eosinophilic pneumonia.Here we present a 25-year-old woman with ulcerative colitis with bloody diarrhea accompanied by abdominal pain and fever which were aggravated after introduction of mesalamine suppositories.In light of symptom exacerbation of ulcerative colitis,increased inflammatory injury of colon mucosa shown by colonoscopy and elevated peripheral eosinophil count after mesalamine suppositories administration,and the Naranjo algorithm score of 10,the possibility of hypersensitivity reaction to mesalamine suppositories should be considered,warning us to be aware of this potential reaction after administration of mesalamine formulations even if it is the suppositories.

Potential rat model of anxiety-like gastric hypersensitivity induced by sequential stress

AIM To establish a rat model of anxiety-like gastric hyper-sensitivity(GHS) of functional dyspepsia(FD) induced by novel sequential stress.METHODS Animal pups were divided into two groups from postnatal day 2: controls and the sequential-stress-treated. The sequential-stress-treated group received maternal separation and acute gastric irritation early in life and restraint stress in adulthood; controls were reared undisturbed with their mothers. Rats in both groups were followed to adulthood(8 wk) at which point the anxietylike behaviors and visceromotor responses to gastric distention(20-100 mm Hg) and gastric emptying were tested. Meanwhile, alterations in several anxiety-related brain-stomach modulators including 5-hydroxytryptamine(5-HT), γ-aminobutyric acid(GABA), brain-derived neurotrophic factor(BDNF) and nesfatin-1 in the rat hippocampus, plasma and gastric fundus and the 5-HT1 A receptor(5-HT1 AR) in the hippocampal CA1 subfield and the mucosa of the gastric fundus were examined.RESULTS Sequential-stress-treated rats simultaneously demonstrated anxiety-like behaviors and GHS in dose-dependent manner compared with the control group. Although rats in both groups consumed similar amount of solid food, the rate of gastric emptying was lower in the sequentialstress-treated rats than in the control group. Sequential stress significantly decreased the levels of 5-HT(51.91 ± 1.88 vs 104.21 ± 2.88, P < 0.01), GABA(2.38 ± 0.16 vs 5.01 ± 0.13, P < 0.01) and BDNF(304.40 ± 10.16 vs 698.17 ± 27.91, P < 0.01) in the hippocampus but increased the content of nesfatin-1(1961.38 ± 56.89 vs 1007.50 ± 33.05, P < 0.01) in the same site; significantly decreased the levels of 5-HT(47.82 ± 2.29 vs 89.45 ± 2.61, P < 0.01) and BDNF(257.05 ± 12.89 vs 536.71 ± 20.73, P < 0.01) in the plasma but increased the content of nesfatin-1 in it(1391.75 ± 42.77 vs 737.88 ± 33.15, P < 0.01); significantly decreased the levels of 5-HT(41.15 ± 1.81 vs 89.17 ± 2.31, P < 0.01) and BDNF(226.49 ± 12.10 vs 551.36 ± 16.47, P < 0.01) in the gastric fundus but increased the content of nesfatin-1 in the same site(1534.75 ± 38.52 vs 819.63 ± 38.04, P < 0.01). The expressions of 5-HT1 AR in the hippocampal CA1 subfield and the mucosa of the gastric fundus were down-regulated measured by IHC(Optical Density value: Hippocampus 15253.50 ± 760.35 vs 21149.75 ± 834.13; gastric fundus 15865.25 ± 521.24 vs 23865.75 ± 1868.60; P < 0.05, respectively) and WB(0.38 ± 0.01 vs 0.57 ± 0.03, P < 0.01)(n = 8 in each group). CONCLUSION Sequential stress could induce a potential rat model of anxiety-like GHS of FD, which could be used to research the mechanisms of this intractable disease.