Key factors in developing the trinitrobenzene sulfonic acid-induced post-inflammatory irritable bowel syndrome model in rats

AIM:To investigate the key factors in developing the trinitrobenzene sulfonic acid(TNBS)-induced postinflammatory irritable bowel syndrome(PI-IBS)model in rats. METHODS:TNBS was administered to rats at the following conditions:(1)with different doses(20,10,5 mg/0.8 mL per rat);(2)with same dose in different concentrations(20 mg/rat,25,50 mg/mL);(3)in different ethanol percentage(25%,50%);and(4)at depth either 4 cm or 8 cm from anus.At 5 d and 4 wk after TNBS administration,inflammation severity and inflammation resolution were evaluated.At 4 and 8 wk after TNBS application,visceral hyperalgesia and enterochromaffin(EC)cell hyperplasia were assayed by abdominal withdrawal reflex test,silver staining and capillary electrophoresis. RESULTS:Our results showed that:(1)TNBS induced dose-dependent acute inflammation and inflammation resolution.At 5 d post TNBS,the pathological score and myeloperoxidase(MPO)activity in all TNBS treated rats were significantly elevated compared to that of the control(9.48±1.86,8.18±0.67,5.78± 0.77 vs 0,and 3.55±1.11,1.80±0.82,0.97±0.08 unit/mg vs 0.14±0.01 unit/mg,P<0.05).At 4 wk post TNBS,the pathological score in high and median dose TNBS-treated rats were still significantly higher than that of the control(1.52±0.38 and 0.80±0.35 vs 0,P<0.05);(2)Intracolonic TNBS administration position affected the persistence of visceral hyperalgesia.At 4 wk post TNBS,abdominal withdrawal reflex (AWR)threshold pressure in all TNBS-treated groups were decreased compared to that of the control(21.52 ±1.73 and 27.10±1.94 mmHg vs 34.44±1.89 mmHg,P<0.05).At 8 wk post TNBS,AWR threshold pressure in 8 cm administration group was still significantly decreased(23.33±1.33 mmHg vs 36.79±2.29 mmHg,P<0.05);(3)Ethanol percentage affected the TNBS-induced inflammation severity and visceral hyperalgesia.In TNBS-25%ethanol-treated group,the pathological score and MPO activity were significantly lowered compared to that of the TNBS-50%ethanoltreated group,while AWR threshold pressure were significantly elevated(36.33±0.61 mmHg vs 23.33±1.33 mmHg,P<0.05);and(4)TNBS(5 mg/0.8 mL per rat, in 50%ethanol,8 cm from anus)-treated rats recovered completely from the inflammation with acquired visceral hyperalgesia and EC cell hyperplasia at 4 wk after TNBS administration.CONCLUSION:TNBS dosage,concentration,intraco-lonic administration position,and ethanol percentage play important roles in developing visceral hyperalgesia and EC cell hyperplasia of TNBS-induced PI-IBS rats.

Modulation of antiviral cytokine production and lung protection against influenza virus by the glycosides from Ligustrum purpurascens

Ligustrum purpurascens has been used as a traditional herb for over 2,000 years in China.This study was design to investigate the modulation of antiviral cytokines and reduction in lung inflammation of virus-infected mice by the glycosides isolated from Ligustrum purpurascens.Methods:Ligustrum purpurascens glycosides(LPG)were isolated from the leaves of Ligustrum purpurascens.Proliferation of spleen lymphocytes were investigated after LPG treatment.The in vitro and in vivo cytokine modulation of LPG was studied.Furthermore,the anti-inflammatory and antiviral activities of LPG,with the potential to reduce inflammatory lung disorders,were investigated by influenza A virus infected mice.Results:LPG could significantly promote the proliferation,and also could stimulate the production of IFN-γby spleen lymphocytes in a dose-dependent manner.IFN-γexpression level was increased significantly compared to the control and presented a dose-dependent manner in vitro.Furthermore,LPG inhibit the expression of TNF-αand IL-10,which return to normal level in the cyclophosphamide-induced mice model in vivo.Besides,the histopathological analysis indicated LPG reduced acute lung injury in mice infected with influenza virus.Conclusion:This study suggested that LPG could increase the exression of IFN-γ,immunoregulation and decrease lung inflammation of virus-infected mice.

Chinese Herbal Medicine for Ulcerative Colitis:A Systematic Review Protocol

Introduction: This manuscript aims to provide a protocol of systematic review to assess the safety and effectiveness of Chinese herbal medicine(CHM) for the treatment of ulcerative colitis(UC). Although CHM has been widely used for UC, its effectiveness and safety has not yet been well defined and analyzed.Methods and analysis: Seven electronic databases were searched, including China National Knowledge Infrastructure(CNKI), Chinese Biomedical literature(CBL), VIP database, Cochrane Library, MEDLINE, PubMed and China Journals Full-text Database. Related Chinese literature will be searched in other Chinese databases. All relevant randomized controlled literature of publication type will be included.Assessment of risk of bias, data synthesis and subgroup analysis will be carried out using Review Manager 5.2.Ethics and dissemination: The results of the systematic review will be disseminated via publication in a peer-reviewed journal and presented at a relevant conference.

First total synthesis of natural products cajanolactone A and cajanonic acid A

First total synthesis of cajanolactone A and cajanonic acid A has been achieved through steps of anion–anion condensations,cyclization,Williams etherification,selective demethylation,1 3-sigmatropic rearrangement and hydrolysis.This work provides an efficient method for future cajanonic acid A derivatives synthesis.

Modified injection technique for improving the treatment of keloids

To the Editor:Keloids are a specific type of scar that exceeds the original wound boundary and unlikely to shrink spontaneously.Numerous methods for treating keloids have been reported,including surgical resection,radiation,injection,laser therapy,and cryotherapy.However,no single method can ensure a complete cure.Among the reported methods,the intralesional injection of steroids is widely used.A large number of studies have shown that the injection of glucocorticoids combined with 5-fluorouracil(5-FU)into the keloid can soften the texture,reduce the volume,and relieve the associated symptoms.[1]The conventional intralesional injection was routinely performed by directly injecting the drug into the parenchyma through the surface of the keloid in a multipoint manner.