Protective effect of embelin against acetic acid induced ulcerative colitis in rats

Amino acid HPLC-FLD analysis of spirulina and its protective mechanism against the combination of obesity and colitis in wistar rats

Objective

The cafeteria diet (CD), designed as an experimental diet mimicking the obesogenic diet, may contribute to the pathogenesis of inflammatory bowel diseases (IBD). This study delves into the influence of spirulina (SP) on obesity associated with colitis in Wistar rats.

Methods

The amino acids composition of SP was analyzed using HPLC-FLD. Animals were equally separated into eight groups, each containing seven animals and treated daily for eight weeks as follows: Control diet (SD), cafeteria diet (CD) group, CD + SP (500 mg/kg) and SD + SP. Ulcerative colitis was provoked by rectal injection of acetic acid (AA) (3 % v/v, 5 ml/kg b.w.) on the last day of treatment in the following groups: SD + AA, SD + AA + SP, CD + AA, and CD + AA + SP.

Results

Findings revealed that UC and/or CD increased the abdominal fat, weights gain, and colons. Moreover, severe colonic alteration, perturbations in the serum metabolic parameters associated with an oxidative stress state in the colonic mucosa, defined by overproduction of reactive oxygen species (ROS) and increased levels of plasma scavenging activity (PSA). Additionally, obesity exacerbated the severity of AA-induced UC promoting inflammation marked by the overexpression of pro-inflammatory cytokines. Significantly, treatment with SP provided notable protection against inflammation severity, reduced histopathological alterations, attenuated lipid peroxidation (MDA), and enhanced antioxidant enzyme activities (CAT, SOD, and GPX) along with non-enzymatic antioxidants (GSH and SH-G).

Conclusions

Thus, the antioxidant effects and anti-inflammatory proprieties of SP could be attributed to its richness in amino acids, which could potentially mitigate inflammation severity in obese subjects suffering from ulcerative colitis. These results imply that SP hold promise as a therapeutic agent for managing of UC, particularly in individuals with concomitant obesity. Understanding SP's mechanisms of action may lead novel treatment strategies for inflammatory bowel diseases and hyperlipidemia in medical research.

Recent advances in anti-inflammatory active components and action mechanisms of natural medicines

Inflammation is a series of reactions caused by the body's resistance to external biological stimuli. Inflammation affects the occurrence and development of many diseases. Anti-inflammatory drugs have been used widely to treat inflammatory diseases, but long-term use can cause toxic side-effects and affect human functions. As immunomodulators with long-term conditioning effects and no drug residues, natural products are being investigated increasingly for the treatment of inflammatory diseases. In this review, we focus on the inflammatory process and cellular mechanisms in the development of diseases such as inflammatory bowel disease, atherosclerosis, and coronavirus disease-2019. Also, we focus on three signaling pathways (Nuclear factor-kappa B, p38 mitogen-activated protein kinase, Janus kinase/signal transducer and activator of transcription-3) to explain the anti-inflammatory effect of natural products. In addition, we also classified common natural products based on secondary metabolites and explained the association between current bidirectional prediction progress of natural product targets and inflammatory diseases.

The lncRNAs UCA1 and CRNDE target miR-145/TLR4/NF-қB/TNF-α axis in acetic acid-induced ulcerative colitis model: The beneficial role of 3,3-Diindolylmethane

INTRODUCTION

Ulcerative colitis (UC) is a chronic disease that alters the colonic and rectal mucosa. The high prevalence rates of UC make it a worldwide healthcare problem. However, its underlying molecular mechanisms remain vague.

AIM OF THE STUDY

To investigate the molecular mechanisms underlying UC and to study the cross-talk among the regulatory role of the lncRNAs UCA1, CRNDE, and miR-145 on TLR4/NF-κB/TNF-α signaling pathway. Moreover, the study was extended to examine the beneficial effects of 3,3-Diindolylmethane (DIM) on relieving UC.

METHODS

UC was induced in rats by injecting 2 ml of 4% acetic acid (AA) solution transrectally. After 24 h, rats were treated with either DIM (20 mg/kg) or sulphasalazine (SSZ) (500 mg/kg) orally for 7 days.

RESULTS

The present study revealed that the gene expression of the lncRNAs UCA1 and CRNDE were significantly upregulated in the AA-induced UC model compared with the control group, whereas miR-145 was significantly downregulated. There was a significant association between the expression of these non-coding RNAs and TLR4/ NF-κB/TNF-α axis as well as malondialdehyde and glutathione levels. Favorably, the DIM-treated group showed significant downregulation of the lncRNAs UCA1 and CRNDE along with upregulated miR-145 compared with the AA-induced UC model. Furthermore, DIM showed remarkable inhibition of the TLR4/ NF-κB /TNF-α cascade compared with non-treated UC rats.

CONCLUSIONS

The present study is the first to document the interrelated role of the lncRNAs UCA1 and CRNDE in UC via orchestrating miR-145/TLR4/ NF-κB /TNF-α inflammatory cascade. Furthermore, the study demonstrated a new molecular basis for the pleiotropic activities of DIM in relieving UC.

Acetic acid-induced colitis modulating potential of total crude alkaloidal extract of Picralima nitida seeds in rats

PURPOSE

The total crude alkaloidal extract of Picralima nitida seeds (PNE) is known to possess anti-inflammatory activity among other therapeutic benefits although its benefits in colitis has not been investigated. The current study therefore seeks to investigate the anti-colitis potential of PNE using acetic acid-induced colitis model in rats.

METHODS

Sprague Dawley rats were treated with oral 500 mg/kg sulphasalazine or 30, 100, and 300 mg/kg of PNE daily for 8 days with induction of colitis on the fourth day with acetic acid. Rats were killed 24 h after the last treatment and whole blood was obtained from the jugular vein for hematological analysis and biochemical assays. Colons were extirpated for assessment of macroscopic and histological damage to the colon.

RESULTS

Treatment with PNE protected against colonic injury induced with acetic acid by decreasing mucosal ulceration, epithelial erosion, inflammatory cell infiltration, and colonic edema. Thus, PNE preserved mucosal architecture and suppressed goblet cells depletion. Moreover, treatment with PNE was associated with improved hematological parameters and reductions in the expression of serum tumor necrosis factor-alpha, interleukin-1β, and p38 mitogen-activated protein kinase. Also, PNE treatment exerted antioxidant effects by reducing nitric oxide production and increasing glutathione levels. In addition, PNE inhibited colonic lipid peroxidation by decreasing myeloperoxidase activity and malondialdehyde production.

CONCLUSION

It can be concluded that PNE attenuates intestinal oxidative and inflammatory damages following intrarectal acetic acid challenge. Thus, demonstrates potential for use in chronic intestinal inflammatory diseases such as ulcerative colitis.

Apigenin and Exposure to Low Dose Gamma Radiation Ameliorate Acetic Acid-Induced Ulcerative Colitis in Rats

Ulcerative colitis (UC) is an inflammatory bowel disease involving chronic and recurring colon inflammation. Current management protocols are limited by adverse effects or short-term symptomatic relief. We aimed to investigate the possible therapeutic prospect of low dose gamma (γ) irradiation or apigenin treatment in acetic acid-induced UC in rats. Induction of UC was carried out by installation of acetic acid intra-rectally. One hour post-induction, rats received a sole dose of γ-radiation (0.5 Gray) or were treated with apigenin (3 mg/kg/day, peroral) for 7 successive days. Antioxidant and anti-inflammatory effects of both agents were assessed via determination of colon malondialdehyde (MDA), reduced glutathione (GSH), total nitrate/nitrite (NOx), mucosal addressin cell adhesion molecule-1 (MAdCAM-1), and interleukin-1beta (IL-1β) contents as well as myeloperoxidase (MPO) activity. Body weight (BW), colon weight/length (W/L) ratio, disease activity index (DAI), and histopathological changes were evaluated. Gamma irradiation and apigenin significantly ameliorated the acetic acid-induced biochemical and histopathological changes. Both therapeutic approaches significantly restored colon contents of the investigated biomarkers. They modulated BW, colon W/L ratio and DAI. This study proposes low dose γ-irradiation as a new therapeutic candidate for the management of UC. We also concluded that apigenin exhibited therapeutic benefits in UC management.

Salkini M, Soliman GA, Alharthy KM, Hamad A, Abdel-Kader MS. Anti-ulcerative colitis effect of Calligonum comosum L'Hér. using rat model: Chemical, pharmacological and histopathological evidences

Calligonum comosum is a perennial shrub growing and widely used in traditional medicinal system in Saudi Arabia. The total phenolic content and in vitro antioxidant activity were compared between the water extract (WE) and methanol extract (ME). The protective potential against acetic acid (AA) induced ulcerative colitis (UC) was also evaluated in rats. The obtained results showed that the total phenolic content of the WE and ME were 8.378 ± 0.738 and 33.819 ± 0.488 µg/mL. The antioxidant properties of the two extracts were directly influenced by their total phenolic contents. The ME with higher phenolic contents and stronger antioxidant power was more effective than the WE in protection against AA-induced colitis. Phytochemical study of the ME led to the identification of three flavonoid derivatives: (-)-epi-catechin, quercetin-3-O-α-l-arabinofuranoside (Avicularin) and quercetin-3-O-β-d-glucuronide-6″-methyl ester by various spectroscopic methods. (-)-Epi-catechin was the major component while the other two compounds were obtained in minute quantities. The anti-ulcerative colitis effect of the ME can be explained by the presence of the antioxidant flavonoids since AA-induced colitis featured by imbalance between oxidant and antioxidant substances. Further support of such explanation was provided by HPLC quantification of (-)-epi-catechin in the ME and WE. The percentage in ME was higher than the WE but the difference was higher in term of Total Phenolic Content (TPC). These results support the traditional use of C. comosum as anti-ulcerative colitis.

Qu-Yu-Jie-Du Decoction Ameliorates Dextran Sulfate Sodium-Induced Colitis in Mice by Modulation of Neutrophils and Macrophage Infiltration

Background. Inflammatory bowel disease (IBD) is becoming a global disease. A percentage of IBD patients will not react to therapy or will lose their response. Qu-Yu-Jie-Du Decoction (QYJD) is a traditional Chinese medicine formula commonly used for intestinal diseases. It has been reported that QYJD has an anti-inflammatory effect, but the mechanism is not fully understood. In this study, we mainly evaluated the anti-inflammatory effect of QYJD and explored the possible mechanisms. Methods. Twenty-four BALB/c mice were randomly divided into 4 groups according to their body weight, namely, the control group, the dextran sulfate sodium (DSS) group, the DSS + QYJD group, and the QYJD group. Mice were given 3% DSS drinking water freely, and at the same time, mice were given normal saline or QYJD (4.44 mg/g/d), respectively. Mental state, faeces, and weight were recorded every day. On the 10th day, the mice were sacrificed and collected for investigation. The length of the mice colon was measured. Histological analysis was used to detect the morphological changes in the colon. Immunohistochemistry was used to measure the infiltration of macrophages (F4/80, CD163) and neutrophils (Ly6G). Colorimetry was used to detect the myeloperoxidase (MPO) activity of colon tissues. ELISA was utilized to detect associated inflammatory cytokines and chemokines in colon tissues. Results. QYJD alleviated the weight loss and colitis symptoms of mice caused by DSS. QYJD fought against the shortening of the intestine caused by DSS; that is, it improved the decline of intestinal compliance in mice and had a protective effect on colon tissues. The mechanisms were related to downregulating macrophages and neutrophils in colon tissues of infiltration. Besides, QYJD simultaneously reduced the activity of myeloperoxidase activity (MPO) and the contents of IL-1β, IL-6, TNF-α, TGF-β, CCL2, and CXCL2 in colon tissues. Conclusions. QYJD can ameliorate DSS-induced colitis in mice and the mechanism is connected with a reduction in neutrophil and macrophage infiltration.

Optimization of Extraction Conditions and Cytotoxic Activity of Rapanone in Comparison to Its Homologue, Embelin

Rapanone is a plant-derived simple alkyl-dihydroxybenzoquinone structurally close to embelin, a well-known cytotoxic agent. The pharmacological characterization of rapanone is still incomplete, and to fill the data gap, a good source for its acquisition is required to conduct further research. This study aimed to optimize the conditions for the extraction of rapanone from the leaves of white-berried Ardisia crenata Sims. For this purpose, three methods were employed: heat reflux (HRE), shaking (SE), and ultrasound-assisted extraction (UAE), and such parameters as the extraction time, solvent, and the number of extractions from the same sample were set as experimental variables. Furthermore, cytotoxic activity toward prostate cancer, thyroid cancer, and colorectal carcinoma cell lines was investigated and compared with doxorubicin and embelin. The most effective and economical method for the extraction of rapanone was shown to be 20 min UAE with ethyl acetate or chloroform. Rapanone exhibited high cytotoxic activity against PC3 (IC₅₀ = 6.50 μg/mL), Du145 (IC₅₀ = 7.68 μg/mL), FTC133 (IC₅₀ = 6.01 μg/mL), 8505C (IC₅₀ = 7.84 μg/mL), and Caco-2 (IC₅₀ = 8.79 μg/mL) cell lines after 24 h and against the HT29 cell line after 48 h (IC₅₀ = 11.67 μg/mL). Furthermore, it revealed a more favorable safety profile than either its homologue, embelin, or doxorubicin. The set of optimal extraction parameters obtained may be utilized for scientific and industrial purposes to achieve the best rapanone yield. Moreover, this benzoquinone revealed a high cytotoxic activity with good selectivity.

Evaluation of Anticolitis and Antioxidant Properties of Bixa orellana (Bixaceae) Leaf Hydroethanolic Extract on Acetic Acid-Induced Ulcerative Colitis in Rats

Background

Ulcerative colitis is an idiopathic inflammatory bowel disease characterized by tissue damage, diarrhea, anemia, and loss of body weight. Tissue damage occurs as a result of uncontrolled activation of the immune response and an increase in free radicals, which have a strong effect on the pathogenesis of inflammatory bowel disease. The incidence and prevalence of this inflammatory disease continue to increase worldwide. Maceration of Bixa orellana leaves in palm wine is used in traditional medicine to treat diarrhea, dysentery, and hemorrhoids in the Adamaoua region of Cameroon.

Objective

The present work evaluated the preclinical effects (ie, antioxidant, hematological, and histological activities) of the hydroethanolic extract of Bixa orellana leaves in an in vivo, rat acetic acid-induced ulcerative colitis model.

Methods

Thirty-six female rats weighing between 165 and 180 g were fasted for 18 hours and then anesthetized with ether. A dose of 1 mL acetic acid (5%) was administered rectally through a catheter in all rats except the normal control group, which received distilled water (1 mL) instead. Treatments began 48 hours after rectal administrations of acetic acid or water, and all animals were treated twice daily for 7 days. The normal control group and the colitis control group received PO distilled water (10 mL/kg), the positive control received orally loperamide (5 mg/kg, and the 3 test groups received orally the hydroethanolic extract of Bixa orellana at 100, 200, and 400 mg/kg, respectively. During treatment, the number of diarrheal stools and weight change were assessed. At the end of the treatment, the animals were put to death under ether anesthesia. Blood was collected postmortem for evaluation of hematological and antioxidant parameters. The abdomen was opened via a midline incision and the colon was removed and emptied of all contents to assess histological and antioxidant parameters.

Results

During treatment, the number of diarrheal stools was significantly decreased from day 3 in animals treated with 100 (P < 0.05), 200 (P < 0.05), and 400 (P < 0.01) mg/kg extract compared with the colitis control group. The change in body weight of all extract-treated rats decreased significantly from day 3 (–5.55%; P < 0.05) to day 8 (–13.80%; P < 0.01) compared with the normal control. In the colitis control, this change ranges from –6.15% on day 2 to –15.13% on day 8. Extract treatment with 100, 200, and 400 mg/kg significantly reduced (P < 0.05) the number of lesions and the relative weight of the colon. The levels of red blood cells, neutrophils, and total white blood cells decreased in the colitis control group, whereas treatment with the extract at doses of 100, 200, and 400 mg/kg was associated with a significant increase in these hematological parameters. Catalase and superoxide dismutase activity and glutathione concentrations all increased significantly (P < 0.01) in blood and colon in all extract-treated animals, whereas levels of malondialdehyde and nitric oxide were significantly decreased (P < 0.01) compared with the colitis control animals.

Conclusions

The hydroethanolic extract of Bixa orellana leaves had protective effects against acetic acid-induced ulcerative colitis in rats that was associated with inhibited production of free radicals believed to be responsible for oxidative stress, hematological disorders, and tissue damage in this animal model.

Embelin Alleviates Severe Airway Inflammation in OVA-LPS-Induced Rat Model of Allergic Asthma

BACKGROUND

Asthma is a chronic lung disease, which causes wheezing, tightness in the chest, shortness of breath and coughing. In the wake of coronavirus disease 2019 (COVID-19), which affect the lungs, asthma patients are at high risk. Embelin, a natural benzoquinone obtained mainly from Embelia ribes Burm, has excellent biological properties, including protection against acute asthma. However, since asthma is a chronic and multi-factorial inflammatory disease, asthma conferred by a single allergen in an animal may not be clinically significant. Therefore, the purpose of the current study was to evaluate the effectiveness of embelin against ovalbumin (OVA)-lipopolysaccharide (LPS)-induced severe airway inflammation in experimental animals and to investigate the plausible mechanism of action.

METHODS

Rats (n=36) were divided into six groups. Group I served as a normal control. Groups II-VI were sensitised with severe allergens (OVA and LPS) on day 7, 14 and 21, followed by OVA and LPS challenge for 30 min three times/week for 3 weeks. Group II acted as an asthmatic disease control and received only vehicle. On the other hand, groups III-V received embelin (12.5, 25 and 50 mg/kg, P.O. respectively) while group VI received a standard dexamethasone (2.5 mg/kg, P.O.) for 15 days from day 27. Lung function parameters, including the respiratory rate, tidal volume and airflow rate were measured at the end of the experiment (day 42). The total and differential counts of leukocytes in the blood and bronchoalveolar fluid (BALF) were calculated. Th2-mediated serum pro-inflammatory cytokines such as interleukin (IL)-4, IL-5 and IL-13 levels were analyzed. At the end of the study protocol, the lung tissues were removed for a histopathology study. Additionally, a molecular docking simulation on embelin and standard dexamethasone was applied to support the in vivo findings.

RESULTS

Significant inhibition of eosinophils, neutrophils, lymphocytes and monocytes in the blood and the BALF was seen in the groups, which received embelin (25 and 50 mg/kg) and dexamethasone (2.5 mg/kg). Moreover, the lung function parameters were normalised by embelin (25 and 50 mg/kg) treatment significantly. The lung histopathological changes confirmed the protective effect of embelin against severe airway inflammation. The docking findings indicated good binding efficacy of embelin to IL-13.

CONCLUSION

Overall, our findings indicate that embelin can alleviate severe airway inflammation in OVA-LPS-induced model of allergic asthma occurring by suppression of Th2-mediated immune response. Due to its promising anti-asthmatic effect, it is recommended that embelin should be investigated in clinical trials against asthma. It should also be further explored against COVID-19 or COVID-like diseases due to its ameliorative effects on cytokines and immune cell infiltration.

Embelin: A novel XIAP inhibitor for the prevention and treatment of chronic diseases

Chronic diseases are a serious health concern worldwide, especially in the elderly population. Most chronic diseases like cancer, cardiovascular ailments, neurodegenerative disorders, and autoimmune diseases are caused due to the abnormal functioning of multiple signaling pathways that give rise to critical anomalies in the body. Although a lot of advanced therapies are available, these have failed to entirely cure the disease due to their less efficacy. Apart from this, they have been shown to manifest disturbing side effects which hamper the patient's quality of life to the extreme. Since the last few decades, extensive studies have been done on natural herbs due to their excellent medicinal benefits. Components present in natural herbs target multiple signaling pathways involved in diseases and therefore hold high potential in the prevention and treatment of various chronic diseases. Embelin, a benzoquinone, is one such agent isolated from Embelia ribes, which has shown excellent biological activities toward several chronic ailments by upregulating a number of antioxidant enzymes (e.g., SOD, CAT, GSH, etc.), inhibiting anti-apoptotic genes (e.g., TRAIL, XIAP, survivin, etc.), modulating transcription factors (e.g., NF-κB, STAT3, etc.) blocking inflammatory biomarkers (e.g., NO, IL-1β, IL-6, TNF-α, etc.), monitoring cell cycle synchronizing genes (e.g., p53, cyclins, CDKs, etc.), and so forth. Several preclinical studies have confirmed its excellent therapeutic activities against malicious diseases like cancer, obesity, heart diseases, Alzheimer's, and so forth. This review presents an overview of embelin, its therapeutic prospective, and the molecular targets in different chronic diseases.

Antioxidant and anti-inflammatory effects of hesperidin methyl chalcone in experimental ulcerative colitis

Neutrophil infiltration, pro-inflammatory cytokines, and reactive oxygen species (ROS) production have been implicated in development and progression of ulcerative colitis (UC), an inflammatory bowel disease (IBD) characterized by ulcerating inflammation of the mucosal layer generally restricted to the colon. The side effects, safety and human intolerance are limitations of the currently approved treatments for UC. Hesperidin methyl chalcone (HMC) is a flavonoid used to treat chronic venous disease, which shows anti-inflammatory, analgesic, and antioxidant properties in pre-clinical studies, however, its effects on colitis have never been described. Therefore, we aimed to evaluate the protective effects of HMC in a mouse model of acetic acid-induced colitis. Treatment with HMC significantly reduced neutrophil infiltration, edema, colon shortening, macro and microscopic damages induced by intracolonic administration of acetic acid. The improvement of colitis after HMC treatment is related to the increase in colon antioxidant status, and the inhibition of pro-inflammatory cytokines TNF-α, IL-6, IL-1β, and IL-33 in the colon. We observed, moreover, that HMC inhibited NF-κB activation in the colon, which might explain the reduction of the cytokines we observed. Finally, these results demonstrate a novel applicability of HMC to increase antioxidant response and reduce inflammation during acetic acid-induced colitis suggesting it as a promising therapeutic approach for the treatment of ulcerative colitis.

Quinones as preventive agents in Alzheimer's diseases: focus on NLRP3 inflammasomes

OBJECTIVES

Alzheimer's disease (AD) is a hidden neurological degenerative disease, which main clinical manifestations are cognitive dysfunction, memory impairment and mental disorders. Neuroinflammation is considered as a basic response of the central nervous system. NLRP3 (Nucleotide-binding domain leucine-rich repeat (NLR) and pyrin domain containing receptor 3) inflammasome is closely related to the occurrence of neuroinflammation. Activation of the NLRP3 inflammasome results in the release of cytokines, pore formation and ultimately pyroptosis, which has demonstrated one of the critical roles in AD pathogenesis. Inhibition of the activity of NLRP3 is one of the focuses of the research. Therefore, NLRP3 represents an attractive pharmacological target, and discovery compounds with good NLRP3 inhibitory activity are particularly important.

KEY FINDINGS

Quinones have good neuroprotective effects and prevent AD, which may be related to their regulation of inflammatory response. The molecular docking was used to explore 12 quinones with AD prevention and treatment and NLRP3. Docking results showed that the combination of anthraquinones and NLRP3 were the best, and the top two chemical compounds were Purpurin and Rhein, which are the most promising NLRP3 inhibitors.

SUMMARY

These quinones may provide the theoretical basis for finding lead compounds for novel neuroprotective agents.

Phloretin Ameliorates Acetic Acid Induced Colitis Through Modulation of Immune and Inflammatory Reactions in Rats

BACKGROUND

Adverse effects associated with current therapy for Ulcerative colitis (UC) over prolonged treatment periods and the high relapse rate limit their use. Incorporating fruits as regular diet has beneficial role in the management of UC. Phloretin, a dihydrochalcone of apple is reported for its anti-oxidant and anti-inflammatory effects. Our study aims to evaluate the effectiveness of phloretin on experimentally induced ulcerative colitis in rats.

METHODS

In vitro study was performed using Raw 264.7 cells stimulated with LPS (1μg/mL) and in in-vivo study, colitis was induced by intra rectal administration of 4% Acetic acid. Phloretin (50 mg/kg) was given orally for 3 days to Wistar rats after induction for the post-treatment group and 1 day before induction to the pre-treatment group. Macroscopical, biochemical and histopathological evaluations were performed to assess the effectiveness.

RESULTS

A concentration dependent inhibition of MPO and iNOS activity was obtained in LPS stimulated neutrophil cells. Phloretin exerted ameliorative effect in both pre and post-treatment groups by restoring plasma ALP and LDH level and reduce inflammatory markers like myeloperoxidase, nitric oxide and eosinophil peroxidase level as well as downregulates colon ICAM-1 gene in acetic acid induced ulcerative colitis in rats. Antioxidative potency was confirmed by restoring tissue GSH level. Phloretin prevents mucosal damage and it was confirmed by histopathological analysis.

CONCLUSION

Collectively, our findings provide evidence that phloretin might be useful as a natural therapeutic agent in the management of UC as well as may pose a promising outcome for future clinical usage.

Natural Product-Based Nanomedicine in Treatment of Inflammatory Bowel Disease

: Many synthetic drugs and monoclonal antibodies are currently in use to treat Inflammatory Bowel Disease (IBD). However, they all are implicated in causing severe side effects and long-term use results in many complications. Numerous in vitro and in vivo experiments demonstrate that phytochemicals and natural macromolecules from plants and animals reduce IBD-related complications with encouraging results. Additionally, many of them modify enzymatic activity, alleviate oxidative stress, and downregulate pro-inflammatory transcriptional factors and cytokine secretion. Translational significance of natural nanomedicine and strategies to investigate future natural product-based nanomedicine is discussed. Our focus in this review is to summarize the use of phytochemicals and macromolecules encapsulated in nanoparticles for the treatment of IBD and IBD-associated colorectal cancer.

Anti-melanoma potential of two benzoquinone homologues embelin and rapanone - a comparative in vitro study

Rapanone and embelin are simple alkyl benzoquinone derivatives, mainly distributed in the Primulaceae. They have an interesting scope of biological activities including cytotoxicity. As melanoma is one of the most common types of cancer, in many cases resistant to current treatment regimens, the aim of this study was to assess and compare anti-melanoma activity of the two benzoquinones. Cytotoxicity of both compounds towards different melanoma cell lines (A375, HTB140, WM793) and selectivity with respect to normal keratinocytes (HaCaT) were investigated. Furthermore, interactions with a reference chemotherapeutic, doxorubicine, were assessed. Finally, analysis of anti-inflammatory, antioxidant and anti-tyrosinase activities of both benzoquinones was conducted as well. Rapanone showed selective and higher than doxorubicine cytotoxic potential against primary melanoma cell line, WM793. Although embelin was also highly cytotoxic, its selectivity was much poorer. Interestingly, in case of HTB140 and HaCaT cell lines a combination of each benzoquinone with doxorubicine potentiated the cytotoxic potential in a synergistic manner. Embelin revealed higher albumin anti-denaturation potential than rapanone but lower than diclofenac sodium. Anti-hyaluronidase effect of both benzoquinones was higher than quercetin. Both compounds showed antioxidant potential although significantly lower as compared to vitamin C. Finally, neither embelin nor rapanone had any inhibitory effect on tyrosinase.

Potential effects of xylopic acid on acetic acid-induced ulcerative colitis in rats

BACKGROUND/AIMS

Xylopic acid (XA) has been reported to exhibit analgesic activity, alleviate neuropathic pain in rodents, and demonstrate anti-inflammatory effects. Intrarectal challenge of rats with acetic acid induces colitis that bears resemblance in terms of its pathogenesis, histopathology, and inflammatory profile to that in humans. Reactive oxygen species are implicated as the main driving force in this inflammatory bowel disease. This study aimed to investigate the anti-colitic potential of XA.

MATERIALS AND METHODS

We investigated the effect of XA on body weight, disease activity, inflammatory cell infiltration, and generation of reactive oxygen species. Rats were treated with XA or sulphasalazine, challenged intrarectally with acetic acid with macroscopic and microscopic findings made after eight days.

RESULTS

Administration of XA to rats with colitis resulted in an increase in body weight with significant (p<0.05) improvement of the disease profile macroscopically. We observed decreased gross mucosal injury, reduced inflammation, and cellular proliferation with XA administration. Treatment with XA also resulted in decreased colonic epithelial expression of argyrophylic nucleolar organizer regions (AgNORs) with significant decrease (p<0.0001) in the quantitative expression of AgNORs/nucleus ratio to levels comparable with non-colitic control. We also observed reduced proliferation of mucosal mast cell in the colonic segment of the rats treated with XA. Treatment with XA also significantly (p<0.0001) increased the activity of SOD, CAT, and APx while it decreased the activity of MPO and MDA levels.

CONCLUSION

Xylopic acid possesses anti-colitic activity in rats induced with acetic acid colitis.

Comparison of Antioxidant and Anti-Inflammatory Effects of Honey and Spirulina platensis with Sulfasalazine and Mesalazine on Acetic Acid-Induced Ulcerative Colitis in Rats

Background:

Antioxidant therapy has gained attention for the treatment of ulcerative colitis (UC). The excessive generation of reactive oxygen/nitrogen species in the gastrointestinal tract increases oxidative stress, thereby leading to antioxidant defense depletion, lipid peroxidation, inflammation, tissue damage, and ulceration. Spirulina platensis (SP) and honey are excellent sources of potent antioxidants such as polyphenols and other bioactive compounds. We aimed to investigate antioxidant and anti-inflammatory effects of honey and SP in comparison with sulfasalazine (SSZ) and mesalazine on acetic acid-induced colitis (AA-colitis) in rats.

Materials and Methods:

Fifty-six Sprague Dawley male rats were allocated to seven groups, with each group comprising eight rats. UC was induced, except in normal controls (NC). All groups received oral treatments for seven days. The normal saline solution of 2 mL was intrarectally administered to the NC group. The AA-colitis and NC groups received 2 mL acetic acid intrarectally as a single dose and 2 mL normal saline for seven consecutive days orally. The mesalazine group received 100 mg/kg mesalazine, the SSZ group 360 mg/kg SSZ, the honey or H group 1 mL honey diluted with 1 mL distilled water, the SH group 1g/kg SP and 1 mL honey, and the SP group 1g/kg SP. After clinical activity score assessment, the rats were sacrificed. Colonic weight/length ratio, prostaglandin E2 (PGE2), myeloperoxidase (MPO), nitric oxide (NO), malondialdehyde (MDA), interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), glutathione peroxidase (GPx), total antioxidant capacity (TAC), reduced glutathione (GSH), and superoxide dismutase (SOD) were measured. Colonic histopathological changes were observed microscopically.

Results:

Treatment of UC with SP, honey, and combination regimen significantly reduced TNF-α, IL-1β, IL-6, MDA, MPO, NO, and PGE2, and increased TAC, GSH, GPx, and SOD in interventional groups compared to the AA-colitis group (P<0.05).

Conclusion:

Honey and SP might be beneficial food supplements for medical nutrition therapy in UC.

Pharmacokinetic and Bioavailability Studies of Embelin after Intravenous and Oral Administration to Rats

Embelin exhibits the broad bioactivities such as antitumor, antifertility, antidiabetic, anti-inflammatory, antioxidant, anticonvulsant, anxiolytic, antimicrobial, and hepatoprotective activity. In order to further understand the pharmacokinetic characteristics and oral bioavailability of embelin in vivo, the concentration of embelin in rat plasma was determined by a sensitive high-performance liquid chromatography with diode array detector (HPLC-DAD). The preparation of samples was accomplished by a simple precipitating protein with methanol. Emodin was selected as the internal standard (IS). Embelin and IS were completely separated on an analytical column (Extend-C18, 4.6 × 250 mm, 5 μm) using 0.1% phosphoric acid in methanol and 0.1% phosphoric acid in aqueous solution (90:10, v/v) as the mobile phase. The lower limit of quantification was 0.15 μg/mL. Oral bioavailability of embelin was 30.2 ± 11.9%. This study could provide the information about pharmacokinetics and oral bioavailability of embelin, which was useful to assess the clinic efficacy and safety and promote further development of embelin.

A systematic review of nano formulation of natural products for the treatment of inflammatory bowel disease: drug delivery and pharmacological targets

Inflammatory bowel diseases (IBD), which is classified into Crohn's disease and ulcerative colitis, are among chronic gastrointestinal diseases with unknown pathogenesis. Diverse strategies have been applied for the treatment of this chronic disease. However, selective and site-specific routes of drug delivery to the inflamed location of the colon remain of high importance. Consequently, the application and effects of natural products in the form of nanoformulation and stimuli responsive nanoparticles as a novel strategy for the treatment of IBD are discussed in this review article. This approach may potentially overcome some complications that are associated with conventional means of colon drug delivery. Meanwhile, in vitro and in vivo studies pave the way for understanding of the mechanism that lies behind this chronic relapsing disease and potentially more effective treatment. Graphical abstract ᅟ.

Fresh Fruit Juice of Opuntia dillenii Haw. Attenuates Acetic Acid-Induced Ulcerative Colitis in Rats

The present study aimed to evaluate the protective effect of fresh fruit juice of Opuntia dillenii Haw. (FJOD) on acetic acid-induced ulcerative colitis in rats. Fresh FJOD (2.5 and 5 ml/kg) and sulfasalazine (100 mg/kg) were given orally for seven consecutive days prior to colitis induction on the eighth day by intrarectal acetic acid (4% v/v) administration. Macroscopic, clinical activity scoring, biochemical, and histopathological examinations of colon were used to assess colonic damage. FJOD and sulfasalazine treatment significantly attenuated the macroscopic damage, clinical activity score, and wet weight of the colon when compared to disease control and further showed significantly reduced levels of myeloperoxidase, malondialdehyde, and serum lactate dehydrogenase and enhanced colonic levels of reduced glutathione. The protective effect of FJOD may be attributed to its antioxidant and anti-inflammatory activities in ulcerative colitis. The observed effects may be due to the presence of phenolics, flavonoids, and betalains in the fruit juice of Opuntia dillenii.

Protective effects of conventional and colon-targeted lycopene and linalool on ulcerative colitis induced by acetic acid in rats

OBJECTIVE

To compare the potential protective effects of conventional and colon-targeted lycopene (TLC) and linalool (TLN) on acetic acid (AA)-induced ulcerative colitis (UC) in rats.

METHODS

Conventional and colon-targeted LC (10 mg/kg) and LN (200 mg/kg) were administered in vivo orally for 7 days and sulfasalazine (100 mg/kg) was also used as reference drug. Then, 4% AA was administered intrarectally to induce UC. Subsequently, the colon tissues were taken as samples for biochemical and histopathological analysis.

RESULTS

Malondialdehyde (MDA), interleukin 1β (IL-1β), IL-6, cyclooxygenase-2 (COX-2) and nuclear factor kappa B (NF-κB) levels were decreased (p < 0.05) in the targeted groups compared to the AA group, whereas nuclear factor-erythroid 2-related factor 2 (Nrf-2) level was increased (p < 0.05). Tumor necrosis factor α (TNF-α) level was also decreased (p < 0.05) and catalase activity (CAT) was increased (p < 0.05) in the TLC group compared to the AA group. IL-1β and IL-6 levels were lower in the TLC group compared to the conventional LC and sulfasalazine groups (p < 0.05). COX-2 and NF-κB levels were lower, while the Nrf-2 level was higher in the targeted groups compared to the conventional groups (p < 0.05). Furthermore, COX-2 level was lower and Nrf-2 level was higher in the targeted groups compared to the sulfasalazine group (p < 0.05).

CONCLUSION

As expected, sulfasalazine was effective on all parameters analyzed, but the colon-targeted pretreatments were more effective from sulfasalazine on some parameters. Therefore, colon-targeted plant-derived therapies might be alternative approaches to provide protection against UC, which deserves to be investigated further.

Mechanism & inhibition kinetics of bioassay-guided fractions of Indian medicinal plants and foods as ACE inhibitors

Hypertension is a becoming a major threat to the world. Angiotensin converting enzyme (ACE) is a key part in the renin angiotensin aldosterone system (RAAS) which control blood pressure. Over expression of RAAS is related with vascular hypertension, ACE inhibition has turned into a noteworthy target for controlling hypertension. In the search of lead molecules from plant origin as a substitute for toxic synthetic drugs, 25 Indian medicinal plants and foods were screened for their ACE inhibitory activity. IC₅₀ (50% inhibition of ACE) values of hydroalcoholic crude extracts and fraction were determined by a colorimetric method. Active fractions were further screened to determine the enzyme kinetics, mode, specificity and mechanism of inhibition. Standardization was done by determining total phenolics and flavonoids as gallic acid and quercetin equivalents/mg of extract respectively. Among 25 crude extracts, Cynara scolymus extract showed the best activity, IC₅₀ value 356.62 μg/mL. ACE inhibition resulting from protein precipitation was highest in Coscinium fenestratum. Lineweaver-Burk plots revealed a competitive mode of inhibition for Punica granatum ethyl acetate fraction. Fractions of Cassia occidentalis, Cynara scolymus and Embelia ribes were found to be non-specific inhibitors of ACE. Embelia ribes, Cassia occidentalis and Coscinium fenestratum fractions inhibited the ACE by Zn²⁺ ion chelation. Research revealed the potential of tested plants fractions as ACE inhibitors along with their inhibition kinetics and mechanism of inhibition. These active plant fractions might find importance in the development of potential antihypertensive agents after further investigations using preclinical and clinical trials.

Embelin: a benzoquinone possesses therapeutic potential for the treatment of human cancer

Natural products have been gaining recognition and are becoming a significant part of research in the area of drug development and discovery. Phytochemicals derived from these sources have been comprehensively studied and have displayed a wide range of activities against many fatal diseases including cancer. One such product that has gained recognition from its pharmacological properties and nontoxic nature is embelin, obtained from Embelia ribes. Amid all the vivid pharmacological activities, embelin has gained its prominence in the area of cancer research. Embelin binds to the BIR3 domain of XIAP, preventing the association of XIAP and caspase-9 resulting in the suppression of cell growth, proliferation and migration of various types of cancer cells. Furthermore, embelin modulates anti-apoptotic pathways by suppressing the activity of NF-κB, PI3-kinase/AKT, JAK/STAT pathway - among others. The present review summarizes the various reported effects of embelin on different types of cancer cells and highlights the cellular mechanisms of action.

Beneficial effect of Amorphophallus paeoniifolius tuber on experimental ulcerative colitis in rats

CONTEXT

The tuber of Amorphophallus paeoniifolius (Dennst.) Nicolson (Araceae), commonly called Suran or Jimmikand, has high medicinal value and is used ethnomedicinally for the treatment of different gastrointestinal and inflammatory disorders.

OBJECTIVE

The present study evaluated the effects of extracts of Amorphophallus paeoniifolius tubers on acetic acid-induced ulcerative colitis (UC) in rats.

MATERIALS AND METHODS

Wistar rats were orally administered methanol extract (APME) or aqueous extract (APAE) (250 and 500 mg/kg) or standard drug, prednisolone (PRDS) (4 mg/kg) for 7 days. On 6th day of treatment, UC was induced by transrectal instillation of 4% acetic acid (AA) and after 48 h colitis was assessed by measuring colitis parameters, biochemical estimations and histology of colon.

RESULTS

APME or APAE pretreatment significantly (p < .05-.001) prevented AA-induced reduction in body weight and increase in colitis parameters viz. stool consistency, colon weight/length ratio and ulcer score, area and index. Extracts treatment attenuated (p < .001) increase in alkaline phosphatase and lactate dehydrogenase in serum and myeloperoxidase activity and cytokines in colon tissue due to AA administration. Extracts treatment prevented AA-induced elevation in lipid peroxidation and decline in activities of superoxide dismutase and catalase and reduced-glutathione content (p < .05-.001) along with histopathological alterations. PRDS also showed similar ameliorative effect on colitis.

DISCUSSION AND CONCLUSION

APME and APAE showed a preventive effect on UC, and ameliorated inflammation and oxidative damage in colon. The effects may be attributed to presence of phytochemicals, betulinic acid, β-sitosterol, and glucomannan. In conclusion, the tuber of Amorphophallus paeoniifolius exhibited an anticolitic effect through anti-inflammatory and antioxidant action.

Ameliorative effect of chromium-d-phenylalanine complex on indomethacin-induced inflammatory bowel disease in rats

Present study was designed to evaluate the effect of chromium-d-phenylalanine complex (Cr (d-phe)₃) on indomethacin-induced inflammatory bowel disease (IBD) in rats. Adult Wistar rats were pretreated with vehicle/Cr (d-phe)₃ (30, 60 and 90μg/kg, p.o.) for 11days. On day 8 and 9, after one h of the above mentioned treatment, indomethacin (7.5mg/kg/day,s.c.) was administered to induce IBD. On day 12, blood samples were collected from animals for lactate dehydrogenase (LDH) estimation and ileum was isolated for macroscopic scoring, biochemical estimation (lipid peroxidation, reduced glutathione and myeloperoxidase activity) and histopathological study. Administration of indomethacin significantly altered the serum LDH, macroscopic and microscopic appearance and biochemical parameters in ileum tissue. Cr (d-phe)₃, at all the tested doses, caused a significant reversal of changes induced by indomethacin. Present study demonstrates the protective effect of Cr (d-phe)₃ against indomethacin-induced IBD in rats. The observed protective effect might be attributed to the antioxidant and anti-inflammatory properties of Cr (d-phe)₃.

Curative effect of Amorphophallus paeoniifolius tuber on experimental hemorrhoids in rats

ETHNOPHARMACOLOGICAL RELEVANCE

Amorphophallus paeoniifolius (Dennst.) Nicolson (Family- Araceae) is a crop of south East Asian origin. In India, its tuber is widely used in ethnomedicinal practices by different tribes for the treatment of piles (hemorrhoids).

AIM

The present study evaluated the effect of methanolic and aqueous extract of Amorphophallus paeoniifolius tuber on croton oil induced hemorrhoids in rats.

MATERIALS AND METHODS

The methanolic extract was standardized with the major phenolic compound, betulinic acid, by HPLC. The hemorrhoids were induced by applying 6% croton oil preparation in the ano-rectal region. Rats were orally administered methanolic and aqueous extract at doses of 250 and 500mg/kg, each for 7 days. Pilex (200mg/kg) was used as reference anti-hemorrhoidal drug. Hemorrhoids were assessed on eighth day by measuring hemorrhoidal and biochemical parameters along with histology of ano-rectal tissue.

RESULTS

Croton oil application caused induction of hemorrhoids as indicated by significant (p<0.001) increase in plasma exudation of Evans blue in ano-rectal tissue, macroscopic severity score and ano-rectal coefficient as compared to normal rats. It significantly (p<0.001) elevated lactate dehydrogenase and cytokines (TNF-α and IL-6) levels in serum and increased myeloperoxidase activity and lipid peroxidation in ano-rectal tissue along with marked histological damage as compared to normal rats. Treatment with tuber extracts and pilex significantly (p<0.05-p<0.001) ameliorated Evans blue exudation, hemorrhoidal parameters and other biochemical parameters with attenuation of tissue damage compared to hemorrhoid control rats. The results indicate that tuber extracts exhibited curative action on hemorrhoids. The aqueous extract showed more pronounced effect than methanolic extract. The effects may be attributed to anti-inflammatory and antioxidant properties.

CONCLUSION

Results indicate that tuber of Amorphophallus paeoniifolius exhibited curative action on hemorrhoids through anti-inflammatory and antioxidant properties. The study validates the ethnomedicinal use of tuber in hemorrhoids and implicates its therapeutic potential as an anti-hemorrhoidal agent.

Development of enteric-coated microspheres of embelin for their beneficial pharmacological potential in ulcerative colitis

The aim of the present study is to develop embelin-loaded enteric-coated microspheres and investigate their pharmacological potential in acetic acid induced ulcerative colitis. The optimized formulation of embelin-loaded microspheres has shown significant sustained release of embelin. Further this formulation significantly reduced the ulcer activity score and oxidative stress, and attenuated the inflammatory changes. Thus it may be concluded that embelin-loaded enteric-coated microspheres have shown delayed release capacity than plain embelin and exerts colon ulcer protective effect in rats.

Coatless alginate pellets as sustained-release drug carrier for inflammatory bowel disease treatment

Conventional alginate pellets underwent rapid drug dissolution and failed to exert colon targeting unless subjected to complex coating. This study designed coatless delayed-release oral colon-specific alginate pellets for ulcerative colitis treatment. Alginate pellets, formulated with water-insoluble ethylcellulose and various calcium salts, were prepared using solvent-free melt pelletization technique which prevented reaction between processing materials during agglomeration and allowed reaction to initiate only in dissolution. Combination of acid-soluble calcium carbonate and highly water-soluble calcium acetate did not impart colon-specific characteristics to pellets due to pore formation in fragmented matrices. Combination of moderately water-soluble calcium phosphate and calcium acetate delayed drug release due to rapid alginate crosslinking by soluble calcium from acetate salt followed by sustaining alginate crosslinking by calcium phosphate. The use of 1:3 ethylcellulose-to-alginate enhanced the sustained drug release attribute. The ethylcellulose was able to maintain the pellet integrity without calcium acetate. Using hydrophobic prednisolone as therapeutic, hydrophilic alginate pellets formulated with hydrophobic ethylcellulose and moderately polar calcium phosphate exhibited colon-specific in vitro drug release and in vivo anti-inflammatory action. Coatless oral colon-specific alginate pellets can be designed through optimal formulation with melt pelletization as the processing technology.

Microparticles as controlled drug delivery carrier for the treatment of ulcerative colitis: A brief review

Ulcerative colitis is the chronic relapsing multifactorial gastrointestinal inflammatory bowel disease, which is characterized by bloody or mucus diarrhea, tenesmus, bowel dystension, anemia. The annual incidence of ulcerative colitis in Asia, North America and Europe was found to be 6.3, 19.2 and 24.3 per 100,000 person-years. The major challenge in the treatment of ulcerative colitis is appropriate local targeting and drug related side-effects. To overcome these challenges, microparticulate systems seem to be a promising approach for controlled and sustained drug release after oral administration. The main goal of this article is to explore the role of microparticles in ulcerative colitis for the appropriate targeting of drugs to colon. There are different approaches which have been studied over the last decade, including prodrugs, polymeric approach, time released system, pH sensitive system, which show the site specific drug delivery to colon. Among these approaches, microparticulate drug delivery system has been gaining an immense importance for local targeting of drug to colon at a controlled and sustained rate. Combined approaches such as pH dependent and time dependent system provide the maximum release of drug into colon via oral route. This article embraces briefly about pathophysiology, challenges and polymeric approaches mainly multiparticulate systems for site specific drug delivery to colon in sustained and controlled manner so that drug related side-effects by reducing dosage frequency can be minimized.

Fisetin, a dietary flavonoid, ameliorates experimental colitis in mice: Relevance of NF-κB signaling

Fisetin, a dietary flavonoid, is commonly found in many fruits and vegetables. Although studies indicate that fisetin has an anti-inflammatory property, little is known about its effects on intestinal inflammation. The present study investigated the effects of the fisetin on dextran sulphate sodium (DSS)-induced murine colitis, an animal model that resembles human inflammatory bowel disease. Fisetin treatment to DSS-exposed mice significantly reduced the severity of colitis and alleviated the macroscopic and microscopic signs of the disease. Moreover, fisetin reduced the levels of myeloperoxidase activity, the production of proinflammatory cytokines, tumor necrosis factor-alpha (TNF-α), interleukin-1 beta (IL-1β) and interleukin-6 (IL-6) and the expressions of COX-2 and iNOS in the colon tissues. Further studies revealed that fisetin suppressed the activation of NF-κB (p65) by inhibiting IκBα phosphorylation and NF-κB (p65)-DNA binding activity and attenuated the phosphorylation of Akt and the p38, but not ERK and JNK MAPKs in the colon tissues of DSS-exposed mice. In addition, DSS-induced decline in reduced glutathione (GSH) and the increase in malondialdehyde (MDA) levels were significantly restored by oral fisetin. Furthermore, the results from in vitro studies showed that fisetin significantly reduced the pro-inflammatory cytokine and mediator release and suppressed the degradation and phosphorylation of IκBα with subsequent nuclear translocation of NF-κB (p65) in lipopolysaccharide (LPS)-stimulated mouse primary peritoneal macrophages. These results suggest that fisetin exerts anti-inflammatory activity via inhibition of Akt, p38 MAPK and NF-κB signaling in the colon tissues of DSS-exposed mice. Thus, fisetin may be a promising candidate as pharmaceuticals or nutraceuticals in the treatment of inflammatory bowel disease.

Antioxidant therapy for treatment of inflammatory bowel disease: Does it work?

Oxidative stress (OS) is considered as one of the etiologic factors involved in several signals and symptoms of inflammatory bowel diseases (IBD) that include diarrhea, toxic megacolon and abdominal pain. This systematic review discusses approaches, challenges and perspectives into the use of nontraditional antioxidant therapy on IBD, including natural and synthetic compounds in both human and animal models. One hundred and thirty four papers were identified, of which only four were evaluated in humans. Some of the challenges identified in this review can shed light on this fact: lack of standardization of OS biomarkers, absence of safety data and clinical trials for the chemicals and biological molecules, as well as the fact that most of the compounds were not repeatedly tested in several situations, including acute and chronic colitis. This review hopes to stimulate researchers to become more involved in this fruitful area, to warrant investigation of novel, alternative and efficacious antioxidant-based therapies.

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Major biomarkers used for evaluation of antioxidant therapy were MPO, TBARS/MDA and glutathione levels.

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Challenges were identified for the yet poor use of antioxidant therapy in IBD.

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This review stimulates the investigation of alternative and efficacious antioxidant therapies.

Animal models of ulcerative colitis developed with chemicals

In recent years, the incidence of ulcerative colitis (UC) has been rising obviously with the changes in people's diet (e.g., high fat diet), and it has become a common digestive system disease as well as a main cause of chronic diarrhea. Patients usually suffer from great pain because of the delayed recovery and repeated attacks of UC, and some of the patients may develop into colon cancer. At present, the pathogenesis of UC is not fully clear, anti-inflammatory drugs are mostly used clinically for the treatment of UC, but their efficacy is not satisfying. Therefore, it is of great significance to further investigate the etiology, mechanisms and new treatment strategies for UC using effective animal models of UC. There are many methods to establish animal models of UC. The present review mainly focuses on the mechanisms, characteristics and applications of UC animal models established using chemical substances.

The X-Linked Inhibitor of Apoptosis Protein Inhibitor Embelin Suppresses Inflammation and Bone Erosion in Collagen Antibody Induced Arthritis Mice

Objective. To investigate the effect of Embelin, an inhibitor of X-Linked Inhibitor of Apoptosis Protein (XIAP), on inflammation and bone erosion in a collagen antibody induced arthritis (CAIA) in mice. Methods. Four groups of mice (n = 6 per group) were allocated: CAIA untreated mice, CAIA treated with Prednisolone (10 mg/kg/day), CAIA treated with low dose Embelin (30 mg/kg/day), and CAIA treated with high dose Embelin (50 mg/kg/day). Joint inflammation was evaluated using clinical paw score and histological assessments. Bone erosion was assessed using micro-CT, tartrate resistant acid phosphatase (TRAP) staining, and serum carboxy-terminal collagen crosslinks (CTX-1) ELISA. Immunohistochemistry was used to detect XIAP protein. TUNEL was performed to identify apoptotic cells. Results. Low dose, but not high dose Embelin, suppressed inflammation as reflected by lower paw scores (P < 0.05) and lower histological scores for inflammation. Low dose Embelin reduced serum CTX-1 (P < 0.05) and demonstrated lower histological score and TRAP counting, and slightly higher bone volume as compared to CAIA untreated mice. XIAP expression was not reduced but TUNEL positive cells were more abundant in Embelin treated CAIA mice. Conclusion. Low dose Embelin suppressed inflammation and serum CTX-1 in CAIA mice, indicating a potential use for Embelin to treat pathological bone loss.

Embelia ribes ameliorates lipopolysaccharide-induced acute respiratory distress syndrome

ETHNOPHARMACOLOGICAL RELEVANCE

Embelia ribes Burm. f. (Fam. Myrsinaceae) locally known as Vidanga have been used for treating tumors, ascites, bronchitis, jaundice, diseases of the heart and brain in traditional Indian medicine. However, no scientific studies providing new insights in its pharmacological properties with respect to acute respiratory distress syndrome have been investigated.

AIM

The present investigation aimed to elucidate the effectiveness of Embelin isolated from Embelia ribes seeds on attenuation of LPS-induced acute respiratory distress syndrome in murine models.

METHODS

Embelin (5, 10 and 20 mg/kg/day, i.p.) and Roflumilast (1 mg/kg/day, p.o.) were administered for four days and prior to LPS in rats (i.t.). Four hour after LPS challenge animals were anesthesized and bronchoalveolar lavage was done with ice-cold phosphate buffer. Assessment of BAL fluid was done for albumin, total protein, total cell and neutrophil count, TNF-α levels, nitrosoative stress. Superior lobe of right lung was used for histopathologic evaluation. Inferior lobe of right lung was used to obtain lung edema. Left lung was used for myeloperoxidase estimation. Arterial blood was collected immediately and analyzed for pH, pO2 and pCO2 were estimated.

RESULTS

Pretreatment with embelin (5, 10 and 20 mg/kg, i.p.) decreased lung edema, mononucleated cellular infiltration, nitrate/nitrite, total protein, albumin concentrations, TNF-α in the bronchoalveolar lavage fluid and myeloperoxidase activity in lung homogenate. Embelin markedly prevented pO2 down-regulation and pCO2 augmentation. Additionally, it attenuated lung histopathological changes in acute respiratory distress syndrome model.

CONCLUSION

The study demonstrates the effectiveness of Embelia ribes Burm. f. (Fam. Myrsinaceae) seeds in acute respiratory distress syndrome possibly related to its anti-inflammatory and protective effect against LPS induced airway inflammation by reducing nitrosative stress, reducing physiological parameters of blood gas change, TNF-α and mononucleated cellular infiltration indicating it as a potential therapeutic agent for acute respiratory distress syndrome.

Evaluation of the protective effect of Pterocarpus marsupium on acetic acid-induced ulcerative colitis in rats

The aim of the study was to evaluate the effect of Pterocarpus marsupium (PM) on acetic acid (AA)-induced ulcerative colitis (UC) in rats. The rats were divided into five groups, each having six rats. PM extract 100 mg and 200 mg/kg was given orally to groups four and five, respectively, and standard drug sulfasalazine (100 mg/kg, p.o) to group three. Group two served as UC control animals, and group one control animals received vehicle for 7 days. UC was induced by administering AA (3 % v/v of 2 ml) to all the animals except group one. After 72 h, the animals were killed and the colon was dissected out for microscopic, clinical evaluation, histopathological study and biochemical estimation. PM (100 and 200 mg/kg)-treated group had significantly reduced colon inflammation and mucosal damage. The treatment also normalized the altered antioxidant enzyme levels (LPO, SOD and GSH). Histopathological studies support the effect. The protective effect of PM may be due to antiinflammatory and antioxidant properties.

Embelin lipid nanospheres for enhanced treatment of ulcerative colitis - Preparation, characterization and in vivo evaluation

Aim of the present study is to develop embelin lipid nanospheres (LNE) for better treatment of ulcerative colitis. Embelin LNs were developed using soya bean oil/virgin coconut oil as liquid lipid carrier and soya/egg lecithin as stabilizer by hot homogenization followed by ultrasonication technique. The particle size of LNEs ranged from 196.1±3.57 to 269.2±1.05nm with narrow polydispersity index values whereas zeta potential was from -36.6 to -62.0mV. Embelin was successfully incorporated into lipid nanospheres with entrapment efficiency about 99%. There was no interaction between embelin and selected liquid lipids which was confirmed by FTIR studies. In vitro drug release studies performed using Franz diffusion cell and results showed sustained release of embelin. Embelin LNs were stabilized with egg and soya lecithin, embelin release from these LNs followed Higuchi model and first order model, respectively, however mechanism of drug release in both LNs was non-Fickian. In vivo studies were carried out using acetic acid induced ulcerative colitis rat model and results revealed that treatment with embelin LNs significantly reduced clinical activity and macroscopic scores compared to embelin conventional suspension. Treatment with embelin LNs decreased MPO, LDH and LPO levels, increased reduced GSH levels which indicated better treatment of ulcerative colitis was achieved. This was also confirmed by improved histopathological conditions. Thus embelin LNs could be favourably used for treatment of ulcerative colitis.