Protection by Ziziphora clinopoides of acetic acid-induced toxic bowel inflammation through reduction of cellular lipid peroxidation and myeloperoxidase activity

Possible Curative Effects of Boric Acid and Bacillus clausii Treatments on TNBS-Induced Ulcerative Colitis in Rats

Crohn's disease (CD) and ulcerative colitis (UC) are two chronic relapsing inflammatory bowel diseases (IBD). Although there are several treatment options available to improve the symptoms of IBD patients, there is no effective treatment that provides a definitive solution. In the present study, we aim to investigate the antioxidative/anti-inflammatory effects of oral administration of boric acid and Bacillus clausii in a rat trinitrobenzenesulfonic acid (TNBS)-induced colitis model. The effects of boric acid and B. clausii were examined in serum and colon tissues with the help of some biochemical and histological analyses. Elevated inflammation and oxidative damage were found in the blood and colon tissue samples in the TNBS-induced group according to the complete blood count (CBC), tumor necrosis factor (TNF) alpha, interleukin-35 (IL-35), malondialdehyde (MDA), glutathione peroxidase (GPx), myeloperoxidase (MPO), nitric oxide (NO), and histological findings. Particularly, the highest IL-35 level (70.09 ± 12.62 ng/mL) in the combined treatment group, highest catalase activity (5322 ± 668.1 U/mg protein) in the TNBS-induced group, and lower relative expression of inducible nitric oxide synthase in the TNBS-induced group than the control group were striking findings. According to our results, it can be concluded that boric acid showed more curative effects, even if B. clausii probiotics was partially ameliorative.

Umbelliferone ameliorates ulcerative colitis induced by acetic acid via modulation of TLR4/NF-κB-p65/iNOS and SIRT1/PPARγ signaling pathways in rats

Ulcerative colitis (UC) is a common chronic, idiopathic inflammatory bowel disease associated with inflammatory perturbation and oxidative stress. Umbelliferone (UMB) is a potent anti-inflammatory and antioxidant coumarin derivative. Depending on the possible mechanisms, we aimed to explore and elucidate the therapeutic potential of UMB on UC-inflammatory response and oxidative injury-induced via intrarectal administration of acetic acid (AA) in rats. Animals were assigned into four groups: control group, UMB (30 mg/kg, oral)-treated group, AA-induced colitis model group (2 ml of AA; 3% v/v), and colitis treated with UMB group. The results showed that UMB improved macroscopic and histological tissue injury caused by the AA. Mechanistically, UMB reduced the elevated colonic TNF-α, IL-6, MPO, and VCAM-1 and downregulated the gene and protein expression of TLR4, NF-κB, and iNOS signaling factors, exhibiting potent anti-inflammatory effects. Moreover, UMB upregulated the gene and protein expression of both SIRT1 and PPARγ signaling pathways, thereby inhibiting both oxidative injury and inflammatory response. Conclusively, UMB protected rats against AA-induced UC by suppressing the TLR4/NF-κB-p65/iNOS signaling pathway and promoting the SIRT1/PPARγ signaling. Our results showed the effectiveness of UMB in alleviating the pathogenesis of UC and introduced it as a possible therapeutic applicant for clinical application.

Myrica salicifolia Hochst. ex A. Rich. suppress acetic acid-induced ulcerative colitis in rats by reducing TNF-alpha and interleukin-6, oxidative stress parameters and improving mucosal protection

Ulcerative colitis (UC) is an inflammatory bowel disease (IBD) with rising prevalence in developing countries, and limited success of current therapies, natural products have immense potential for therapy due to their "disease modifying and side-effect neutralizing" potential. Myrica salicifolia is traditionally used for gastrointestinal diseases and have reported antiinflammatory activities, but its use in IBD has not yet been studied. Therefore, in the present study, the effects of the root extract of M. salicifolia (Ms.Cr) were investigated using the acetic acid-induced UC model in rats. For 6 days, the rats were given either vehicle (10 mL/kg), lower (200 mg/kg), and higher (400 mg/kg) doses of Ms.Cr, or the positive control drug (prednisolone; 2 mg/kg) orally. A single dosage of 5% acetic acid (1.0 mL) was administered intrarectally to rats on day 6 to induce UC. Disease activity index (DAI), histological observations, the biochemical parameters related to oxidative stress, and specific cytokines such as interleukin-6 (IL-6) and the tumor necrosis factor-α (TNF-α) were determined to assess the effect of Ms.Cr. In comparison to the AA-induced colitis rats, Ms.Cr's pretreatment significantly decreased DAI, colonic ulceration, and inflammatory score. Total glutathione levels and catalase activity were considerably recovered in the colitis group treated with Ms.Cr, whereas enhanced lipid peroxidation in colon tissues was significantly decreased. Moreover, Ms.Cr pretreatment also caused inhibition of the activation of IL-6 and TNF-α in the colonic tissues of respective groups. Based on these findings, Ms.Cr might be developed to treat UC in the future.

The physiological and pharmacological effects of Ziziphoratenuior L.: A review study

Objective:

Many reports have revealed preventive and therapeutic effects of Ziziphoratenuior; however, few systematic reviews have evaluated such effects. The present study reviews the physiological and pharmacological effects of Z. tenuior extract and its components.

Materials and Methods:

English articles were searched in international databases, such as Embase, Scopus, and PubMed; Persian studies were also searched in national databases such as SID and Magiran.

Results:

Pulegone is one of the most important effective compounds of Z. tenuior, which has analgesic, anti-inflammatory, and anti-stress properties as it affects serotonergic and opioidergic systems and decreases the gastric acid secretion. Moreover, this compound inhibits cholesterol absorption and synthesis, resulting in hyperlipidemic effects and weight loss. In addition to its antioxidant, antitumor, and antibacterial properties, this herb contains an antidiabetic effect mediated by increasing the number of pancreatic beta cells and insulin secretion, and inhibiting alpha-amylase. Although its effective dosage has no side effects, the overuse of its effective compounds, such as pulegone, may raise some liver and pulmonary disorders.

Conclusion:

Z. tenuior and its extract can have preventive and therapeutic effects on diabetes and hyperlipidemia-associated diseases. Since most studies on this herb were in vivo, it is necessary to design clinical trials to evaluate its effects.

Novel green synthesis and antioxidant, cytotoxicity, antimicrobial, antidiabetic, anticholinergics, and wound healing properties of cobalt nanoparticles containing Ziziphora clinopodioides Lam leaves extract

The aim of the experiment was a green synthesis of cobalt nanoparticles from the aqueous extract of Ziziphora clinopodioides Lam (CoNPs) and assessment of their cytotoxicity, antioxidant, antifungal, antibacterial, and cutaneous wound healing properties. The synthesized CoNPs were characterized using different techniques including UV-Vis., FT-IR spectroscopy, X-ray diffraction (XRD), energy dispersive X-ray spectrometry (EDS), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). According to the XRD analysis, 28.19 nm was measured for the crystal size of NPs. TEM and SEM images exhibited a uniform spherical morphology and average diameters of 29.08 nm for the biosynthesized nanoparticles. Agar diffusion tests were done to determine the antibacterial and antifungal characteristics. Minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), and minimum fungicidal concentration (MFC) were specified by macro-broth dilution assay. CoNPs indicated higher antibacterial and antifungal effects than many standard antibiotics (p ≤ 0.01). Also, CoNPs prevented the growth of all bacteria at 2-4 mg/mL concentrations and removed them at 2-8 mg/mL concentrations (p ≤ 0.01). In the case of antifungal effects of CoNPs, they inhibited the growth of all fungi at 1-4 mg/mL concentrations and destroyed them at 2-16 mg/mL concentrations (p ≤ 0.01). The synthesized CoNPs had great cell viability dose-dependently and indicated this method was nontoxic. DPPH free radical scavenging test was done to assess the antioxidant potentials, which revealed similar antioxidant potentials for CoNPs and butylated hydroxytoluene. In vivo experiment, after creating the cutaneous wound, the rats were randomly divided into six groups: untreated control, treatment with Eucerin basal ointment, treatment with 3% tetracycline ointment, treatment with 0.2% Co(NO₃)₂ ointment, treatment with 0.2% Z. clinopodioides ointment, and treatment with 0.2% CoNPs ointment. These groups were treated for 10 days. For histopathological and biochemical analysis of the healing trend, a 3 × 3 cm section was prepared from all dermal thicknesses at day 10. Use of CoNPs ointment in the treatment groups substantially raised (p ≤ 0.01) the wound contracture, hydroxyl proline, hexosamine, hexuronic acid, fibrocyte, and fibrocytes/fibroblast rate and remarkably decreased (p ≤ 0.01) the wound area, total cells, neutrophil, and lymphocyte compared to other groups. In conclusion, CoNPs can be used as a medical supplement owing to their non-cytotoxic, antioxidant, antibacterial, antifungal, and cutaneous wound healing effects. Additionally, the novel nanoparticles (Co(NO₃)₂ and CoNPs) were good inhibitors of the α-glycosidase, and cholinesterase enzymes.

Protoscolicidal and immunomodulatory activity of Ziziphora tenuior extract and its fractions

OBJECTIVE

To evaluate the scolicidal and immunomodulatory effect of the Ziziphora tenuior (Z. tenuior) extract and its fractions.

METHODS

Protoscolices were treated with six concentrations (3, 5, 10, 25, 50, and 100 mg/mL) of Z. tenuior extract and its fractions (ethanol, petroleum ether, ethyl acetate and chloroform) in periods of 10, 20, 30, 40, 50 and 60 min, and viability of protoscolices was evaluated using the 1.0% eosin. To examine the immunomodulatory effects of Ziziphora and its fractions on macrophage cells, the non-toxic concentration of extract and different fractions determined by MTT assay, and the Griess reaction was used to measure the level of nitrite as an indicator of nitric oxide by the macrophage cells in 10, 100 and 200 μg/mL in 24 h at 37 °C.

RESULTS

In this study, the Z. tenuior extract at 10 mg/mL concentration was able to kill all protoscolices during 20 min. By increasing the concentration to 25 mg/mL, the scolicidal time reduced to 10 min. Regarding the effect of different fractions of Z. tenuior, the ethanolic fraction showed the highest scolicidal activity. The extract demonstrated an inhibitory effect on the activity of macrophages and reduced nitric oxide production. Although the petroleum ether and ethanolic fractions of the extract reduced nitric oxide production, nevertheless, this effect was only significant at 10 and 100 μg/mL concentrations (P < 0.05).

CONCLUSION

The Z. tenuior extract and its fractions were effective against protoscolices yet the effect of total extract was considerable. Our findings indicates that the extract and its ethanolic and petroleum ether fractions could have anti-inflammatory properties.

Kazakh Ziziphora Species as Sources of Bioactive Substances

Ziziphora species represent the prototypical example of the Lamiaceae family. The phytochemicals present in Ziziphora include monoterpenic essential oils, triterpenes and phenolic substances belonging to the flavonoids. In Kazakh traditional medicine, Ziziphora species possess several medicinal uses. In particular, Z. bungeana Lam. and Z. clinopodioides Lam. are used for the treatment of illnesses related to the cardiovascular system or to combat different infections. Unfortunately, the majority of the information about the complex Ziziphora species is only available in Russian and Chinese language, therefore, we decided gather all available information on Kazakhstan Ziziphora, namely its content compounds, medicinal uses and published patents, to draw the attention of scientists to this very interesting plant with high medicinal potential.

The implications of oxidative stress and antioxidant therapies in Inflammatory Bowel Disease: Clinical aspects and animal models

Inflammatory bowel disease (IBD), including Crohn's disease (CD) and ulcerative colitis (UC), is a chronic inflammatory disorder characterized by alternating phases of clinical relapse and remission. The etiology of IBD remains largely unknown, although a combination of patient's immune response, genetics, microbiome, and environment plays an important role in disturbing intestinal homeostasis, leading to development and perpetuation of the inflammatory cascade in IBD. As chronic intestinal inflammation is associated with the formation of reactive oxygen and reactive nitrogen species (ROS and RNS), oxidative and nitrosative stress has been proposed as one of the major contributing factor in the IBD development. Substantial evidence suggests that IBD is associated with an imbalance between increased ROS and decreased antioxidant activity, which may explain, at least in part, many of the clinical pathophysiological features of both CD and UC patients. Hereby, we review the presently known oxidant and antioxidant mechanisms involved in IBD-specific events, the animal models used to determine these specific features, and also the antioxidant therapies proposed in IBD patients.

Immunomodulatory effects of Ziziphora tenuior L. extract on the dendritic cells

Background

Ziziphora tenuior L. (Kakuti in Persian) is used in traditional medicine for treatment of gastrointestinal disorders as carminative and analgesic plant. The other usages of this plant are included treatment of diarrhea and nausea. Therefore in the present study we evaluated the immunomodulatory effects of the ethanolic extract of this plant on the dendritic cells (DCs).

Results

Ziziphora tenuior L. extract significantly (p = 0.002) increased the level of surface expression of CD40 as an important co-stimulatory marker on DCs compared to the control. However this extract did not change CD86 and MHC-II molecules, so it could promote DCs phenotypic maturation. Treatment of DCs with the extract resulted in slightly increased of the production of (IL-12); however, this change was not significant. In addition, the ability of treated DCs to stimulate allogenic T cells proliferation and cytokines secretion was examined in the co-cuture of these cells with T cells in mixed lymphocyte reaction (MLR). Z. tenuior L. at the 100 μg/ml concentration inhibited the proliferation of allogenic T cells and also significantly (P < 0.001) increased the level of IL-10. Moreover, the extract at 10–100 μg/ml concentration caused slightly increase in IFN-γ production and decreased IL-4 cytokines but these changes were not significant.

Conclusions

These findings indicated that Z. tenuior L. extract can modulate immune response by induction of CD40 expression on DCs and cytokine production; whereas it can inhibit T cell stimulating activity of DCs in high concentration. These findings possibly in part explain the traditional use of this plant in treatment of immune-mediated disorders. However future studies are needed.

In vitro evaluation of anti-herpes simplex-1 activity of three standardized medicinal plants from Lamiaceae

BACKGROUND

Rosmarinic acid (RA) is a phenolic acid with antioxidant and anti-viral effects. We have studied anti-herpes simplex virus type 1 (HSV-1) effect of three medicinal plants from Lamiaceae family which have been standardized on the basis of RA content.

MATERIALS AND METHODS

Methanolic extract of Teucrium polium, Ziziphora clinopoides, and Salvia rhytidea was prepared by maceration method and RA content of the plants was determined using a spectrophotometric method. Maximum nontoxic concentration (MNTC) of the extracts was determined using neutral red method. Serial dilutions of extracts up to MNTC were examined on Vero cells for anti-HSV-1 effect by plaque assay in comparison to acyclovir as a positive control.

RESULTS

Among the tested extracts, T. polium contained the highest percentage of RA (1.8%w/w) and exhibited the least toxicity (MNTC = 1000 μg/ml). The greatest anti-HSV-1 was shown by T. polium and Z. clinopoides extracts which exhibited both time and concentration-dependent plaque inhibition.

CONCLUSION

Considering the low toxicity and significant anti-viral effect of T. polium extract, this plant would prove valuable as an active anti-viral drug.

Toxicological and pharmacological concerns on oxidative stress and related diseases

Although reactive oxygen species (ROS) such as superoxide, hydrogen peroxide and hydroxyl radical are generated as the natural byproduct of normal oxygen metabolism, they can create oxidative damage via interaction with bio-molecules. The role of oxidative stress as a remarkable upstream part is frequently reported in the signaling cascade of inflammation as well as chemo attractant production. Even though hydrogen peroxide can control cell signaling and stimulate cell proliferation at low levels, in higher concentrations it can initiate apoptosis and in very high levels may create necrosis. So far, the role of ROS in cellular damage and death is well documented with implicating in a broad range of degenerative alterations e.g. carcinogenesis, aging and other oxidative stress related diseases (OSRDs). Reversely, it is cleared that antioxidants are potentially able to suppress (at least in part) the immune system and to enhance the normal cellular protective responses to tissue damage. In this review, we aimed to provide insights on diverse OSRDs, which are correlated with the concept of oxidative stress as well as its cellular effects that can be inhibited by antioxidants. Resveratrol, angiotensin converting enzyme inhibitors, angiotensin receptor blockers, statins, nebivolol and carvedilol, pentaerythritol tetranitrate, mitochondria-targeted antioxidants, and plant-derived drugs (alone or combined) are the potential medicines that can be used to control OSRD.

Promising effect of Magliasa, a traditional Iranian formula, on experimental colitis on the basis of biochemical and cellular findings

AIM: To investigate the efficacy of Magliasa, a traditional Iranian formula, on experimental colitis.

METHODS: After botanical authentication of herbal ingredients, formulation of Magliasa, quantitative determination of total glucosinolates and total phenolic content, and analysis of the thin layer chromatography profile were performed. Colitis was then induced in male rats by instillation of 2,4,6-trinitrobenzenesulfonic acid (TNBS) in all groups, aside from the Sham group. The experimental groups consisted of: the Sham group that received only normal saline; the Mag-50, Mag-100 and Mag-200 groups, which received 50, 100 and 200 mg/kg per day of Magliasa, respectively; the control group, which received vehicle water orally; the infliximab group, which received infliximab (5 mg/kg per day, subcutaneously); and the Dexa group, which received dexamethasone (1 mg/kg per day, orally). After completing the treatment period (2 wk), the rats were sacrificed, the colon was removed, its macroscopic and microscopic changes were recorded, and tumor necrosis factor-alpha (TNF-α), interleukin-1 beta (IL-1β), total antioxidant capacity, myeloperoxidase (MPO), and lipid peroxidation (LPO) were assessed in colon homogenate.

RESULTS: The mean value of total glucosinolates in one gram of Magliasa was 19 ± 1 μmol. The mean value of the total phenolic content was 293.8 ± 17.6 mg gallic acid equivalents per 100 gram of Magliasa. Macroscopic scores were significantly decreased in Mag-100 (1.80 ± 0.58, P = 0.019) and Mag-200 (1.20 ± 0.20, P = 0.001) compared to the control group (3.40 ± 0.24), although some inflammation and hyperemia were evident. Treatment of rats by dexamethasone (0.33 ± 0.21, P < 0.001) and infliximab (0.83 ± 0.31, P < 0.001) remarkably attenuated scores where mild hyperemia was observed macroscopically. In comparison to the control group (4.00 ± 0.32), only Mag-200 (1.60 ± 0.40) showed a significant decrease in colonic histopathological scores (P = 0.005). Minimal mucosal inflammation was observed in the Dexa group (0.67 ± 0.21, P < 0.001). The levels of TNF-α, IL-1β and MPO were significantly lower in all groups compared to the controls (P < 0.05). A significant decrease in LPO was seen in the Mag-200 (3.27 ± 0.77, P = 0.01) and Dexa (3.44 ± 0.22, P = 0.011) groups in comparison to the control group (6.43 ± 0.61). Only dexamethasone caused a significant increase in antioxidant power in comparison to the control group (346.73 ± 9.9 vs 228.33 ± 2.75, P < 0.001). Infliximab and different doses of Magliasa did not show any remarkable increase in antioxidant capacity (P > 0.05). The effect of Magliasa in all of mentioned parameters, except antioxidant capacity, was dose dependent.

CONCLUSION: The effects of Magliasa in TNBS-induced colitis are encouraging and warrant clinical trials for further confirmation.

Beneficial effect of phosphodiesterase-5 inhibitor in experimental inflammatory bowel disease; molecular evidence for involvement of oxidative stress

ABSTRACT Inflammatory bowel disease (IBD) is a common and chronic gastrointestinal disorder characterized by intestinal inflammation and mucosal tissue damage. Reactive oxygen metabolites (ROMs) play a pathogenic role in IBD. We aimed to examine the protective effect of sildenafil, a cGMP phosphodiesterase inhibitor, in the experimental mouse model of IBD. Intrarectal instillation of acetic acid was used to induce IBD. Prednisolone was used as the standard drug for comparison. Sildenafil was used at doses of 0.75, 1.5, and 3 mg/kg. Biochemicals and macroscopic and microscopic examinations of colonic tissue were performed. Results indicated that activity of myeloperoxidase (MPO) and lipid peroxidation product (TBARS) markers of oxidative stress are increased in acetic acid-treated groups and are recovered by sildenafil pretreatment and prednisolone. Sildenafil- (1.5 and 3 mg/kg) and prednisolone-treated groups showed significantly lower score values of macroscopic and microscopic characters when compared to the acetic acid-treated group. The beneficial effect of sildenafil (3 mg/kg) was comparable to that of prednisolone. It is concluded that sildenafil is helpful in the management of IBD, which is presumably related to its strong antioxidative stress potential mediated through enhanced cGMP. Results of proper clinical trials will determine the possible efficacy of phosphodiesterase-5 inhibitors in human IBD.

A randomized, double blinded, placebo-controlled clinical trial of silymarin in ulcerative colitis

OBJECTIVE

To evaluate the clinical efficacy of silymarin in ulcerative colitis (UC) patients.

METHODS

A randomized double blinded placebo-controlled clinical trial was conducted in 80 UC patients whose disease had been documented and were in remission state between September 2009 and October 2010. Patients were assigned to silymarin group (42 cases) and placebo group (38 cases) using a random number table. Either silymarin (140 mg) or placebo (lactose mono-hydrate, corn starch magnesium stearate) tablets were given once daily for 6 months along with their standard therapy. The efficacies were assessed by disease activity index (DAI), frequency difference of the disease flare-up, and paraclinical data.

RESULTS

Ten patients (4 in the silymarin group due to nausea and 6 in the placebo group due to disease flare-up and abdominal pain) discontinued the study. An improvement in hemoglobin level (11.8±1.6 g/dL vs. 13.4±1.2 g/dL,P<0.05) and erythrocyte sedimentation rate (23.7±11.5 mm/h vs.10.8±3.2 mm/h,P<0.05) was observed in the silymarin group but not in the placebo group. DAI significantly decreased in the silymarin group and reached from 11.3±3.5 to 10.7±2.8 (P<0.05). Thirty-five out of 38 patients in the silymarin group were in complete remission with no flare-up after 6 months as compared to 21 out of 32 patients in the placebo group (P=0.5000).

CONCLUSION

Silymarin as a natural supplement may be used in UC patients to maintain remission.

On the benefit of Teucrium in murine colitis through improvement of toxic inflammatory mediators

Regarding the role of free radicals in pathogenesis of inflammatory bowel disease (IBD), we were interested to investigate the effects of Teucrium persicum with approved antioxidant and anti-inflammatory properties in an experimental model of colitis. Immunologic colitis was induced by rectal administration of a mixture of 2,4,6-trinitrobenzene sulphonic acid (TNBS) and ethanol through rubber cannula into rats. Three different doses of Teucrium (100, 200, and 400 mg/kg) were gavaged in a duration of 10 days to rats. Endpoint markers of colitis included macroscopic and microscopic examination of colon tissue and measuring colonic cells concentrations of tumor necrosis factor-alpha (TNF-alpha), interlukin-1beta (IL-1beta), total antioxidant power as ferric reducing antioxidant power (FRAP), myeloperoxidase (MPO), and lipid peroxidation as thiobarbitoric acid-reactive substance (TBARS). Teucrium at all doses improved both macroscopic and histological damages of rats with colitis. Teucrium reduced colonic MPO activity and concentrations of cellular lipid peroxides, TNF-alpha, and IL-1beta, with a concomitant increase in FRAP value in rats with colitis. It is concluded that beneficial effects of Teucrium in experimental colitis is mediated through its antioxidant and anti-inflammatory potentials. Examination of this herbal medicine in patients with IBD as a supplement would further reveal the potential of Teucrium.

Inhibition of tumor necrosis factor and nitrosative/oxidative stresses by Ziziphora clinopoides (Kahlioti); a molecular mechanism of protection against dextran sodium sulfate-induced colitis in mice

Inflammatory bowel disease (IBD) is a chronic condition of the intestine with unknown etiology involving multiple immune genetic and environmental factors. The authors were interested in examining the protective effect of Ziziphora clinopoides methanolic extract, an Iranian folk herbal medicine, on inflammatory mediators in experimental colitis. Colitis in NMRI mice was induced by oral administration of dextran sodium sulfate (DSS, 3%). Z. clinopoides was administrated orally at doses of 75, 150, and 300 mg/kg/day for 7 days. The level of lipid peroxidation (LP), total antioxidant capacity (TAC), total thiol molecules (TTM), antioxidant enzymes including superoxide dismutase (SOD) and catalase (CAT), and nitric oxide (NO) as a marker of nitrosative stress, and tumor necrosis factor alpha (TNF-alpha) as a mediator of inflammation and apoptosis were measured in the colon homogenate. Treatment by DSS increased bowel LP, NO, and TNF-alpha while decreasing TAC, SOD, CAT, and TTM. All measured parameters were improved by Z. clinopoides treatment and reached close to normal levels. The present study further supports the role of oxidative/nitrosative stresses and TNF-alpha in the pathogenesis of colitis and protective effects of this herb. The data are promising for further preclinical studies directed towards understanding mechanism of action and cross-species and cross-model comparisons for potential protective effects.

On the benefits of silymarin in murine colitis by improving balance of destructive cytokines and reduction of toxic stress in the bowel cells

Inflammatory bowel disease (IBD) is a multifactorial disease with an unknown etiology characterized by oxidative stress, leucocyte infiltration and a rise in inflammatory cytokines. In this study, we have investigated the effects of silymarin, a mixture of several flavonolignans with established antioxidant and anti-inflammatory properties, on trinitrobenzene sulphonic acid (TNBS)-induced colitis in rats. Experimental colitis was induced in male Wistar-albino rats by delivering TNBS to the distal colon. All the medicines were administered by gavage for seven days. Thirty-six male rats were divided into six groups containing six rats in each one. Control rats received only TNBS. In the treated groups, animals were given different doses of silymarin (40, 80, and 160 mg/kg). Dexamethasone (1 mg/kg) was used as the positive treatment. Colonic status was investigated seven days post induction of colitis through macroscopic, histological, and biochemical analyses. Amelioration of the morphological signs including macroscopic damage, necrotic area, and histology were seen subsequent to treating animals with silymarin. These observations were accompanied by a significant reduction in the degree of both neutrophil infiltration, indicated by decreased myeloperoxidase activity, and lipid peroxidation, as measured by a decline in malodialdehyde content in inflamed colon as well as a decrease in levels of inflammatory cytokines (TNF-α and IL-1β). The results of the present study reveal that the beneficial effect of silymarin in bowel cells is mediated through its anti-oxidant and anti-inflammatory potentials.

On the use of herbal medicines in management of inflammatory bowel diseases: a systematic review of animal and human studies

Because of potential adverse events and lack of effectiveness of standard therapies, the use of complementary and alternative medicines (CAM), particularly of herbal therapies, for inflammatory bowel disease (IBD) is increasing. Results from the use of herbal therapies for managing IBD are promising, and no serious adverse events have been reported from them. Herbal therapies show their benefit in managing IBD by different mechanisms such as immune system regulation, antioxidant activity, inhibition of leukotriene B4, inhibition of nuclear factor-kappa B (NF-kappaB), and antiplatelet activity. In this paper, all reported herbal therapies established in animal IBD models or used for managing human IBD are systematically reviewed and their possible mechanisms of action discussed. Conducting clinical trials with high quality and validity (randomized, double blinded, controlled, on a large number of patients) to obtain more conclusive results about the use of herbal therapies in IBD is recommended.

Benefit of nicorandil using an immunologic murine model of experimental colitis

Inflammatory bowel disease (IBD) is a chronic inflammatory condition with an unknown etiology. Nicorandil, a potassium channel opener, has been used for many years for the treatment of angina. Recently, it has been shown that nicorandil possesses some novel traits such as anti-apoptotic, gastroprotective, free radical scavenging, and anti-inflammatory properties. Therefore, we set out to examine the possible beneficial effect of nicorandil in a rat model of IBD. Colitis was induced by rectal administration of 2,4,6-trintrobenzene sulphonic acid (TNBS) into rats. Groups of animals used in this study were sham, control, and exposure to dexamethasone, nicorandil, glibenclamid (a pure adenosine triphosphate sensitive potassium channel (KATP) blocker), or nicorandil plus glibenclamid. Drugs were administered by gavage and animals were sacrificed after 7 days. Biochemical markers, including TNF-α and IL-1β, ferric reducing/antioxidant power (FRAP), myeloperoxidase (MPO) activity and thiobarbitoric acid-reactive substance (TBARS), were measured in the homogenate of colonic tissue. Results indicate that nicorandil significantly reduces macroscopic and histological damage induced by TNBS. Nicorandil diminishes MPO activity and levels of TBARS, TNF-∢, and IL-1β in damaged colonic tissue with a concomitant increase in FRAP value (P<0.01). These effects were not reversed by coadministration of glibenclamide. In conclusion, nicorandil is able to ameliorate experimental IBD with a dose in which it does not show any anti-hypertensive effect, and the mechanism of which is partially or totally independent from KATP channels. It is hypothesized that nitric oxide donation and free-radical scavenging properties of nicorandil upregulate endothelial nitric oxide synthase may be responsible for this phenomenon. These findings suggest that nicorandil can be useful in treatment of IBD, although further investigations are needed to elucidate the mechanisms involved.

Molecular evidences on the benefit of N-acetylcysteine in experimental colitis

Inflammatory bowel disease (IBD) is a chronic recurrent disease of the digestive tract with an unknown etiology. The aim of this study was to examine the possible protective effects of N-acetylcysteine (NAC) in the mouse model of IBD by measuring specific biomarkers in the colon cells. Colitis was induced by administration of dextran sodium sulfate (DSS) in drinking water (3%) for 7 days. Three doses of NAC (106, 160, and 240 mg/kg) were given after induction of colitis (4 days post DSS) for 4 days by gavage. Lipid peroxides (LP), total antioxidant power (TAP), total thiol molecules (TTM), tumor necrosis factor-α (TNF-α), nitric oxide (NO), superoxide dismutase (SOD), and catalase (CAT) were measured in the colon homogenate of the treated animals. NAC (160 and 240 mg/kg) significantly decreased LP, TNF-α, NO and increased TTM, SOD, and CAT. The TAP was also increased by NAC (240 mg/kg). It is concluded that moderate to high doses of NAC improves cellular biomarkers of IBD in mice. Further studies should be trialled in humans suffering from two common inflammatory bowel disease called ulcerative colitis and Crohn’s disease.

Oxidative stress and pathogenesis of inflammatory bowel disease: an epiphenomenon or the cause?

Crohn's disease (CD) and ulcerative colitis (UC), known as inflammatory bowel disease (IBD), are fairly common chronic inflammatory conditions of the gastrointestinal tract. Although the exact etiology of IBD remains uncertain, dysfunctional immunoregulation of the gut is believed to be the main culprit. Amongst the immunoregulatory factors, reactive oxygen species are produced in abnormally high levels in IBD. Their destructive effects may contribute to the initiation and/or propagation of the disease. We provided an extensive overview on the evidences from animal and human literature linking oxidative stress to IBD and its activity. Moreover, the effects of antioxidant therapy on IBD patients in randomized, controlled trials were reviewed and the need for further studies elaborated. We also summarized the evidence in support for causality of oxidative stress in IBD.