Miconazole Mitigates Acetic Acid-Induced Experimental Colitis in Rats: Insight into Inflammation, Oxidative Stress and Keap1/Nrf-2 Signaling Crosstalk

Suppression of inflammation in ulcerative colitis rats by avocado and pomegranate

BACKGROUND

Pomegranate seed oil (PSO) and avocado seed oil (ASO) are natural polyphenols with established anti-inflammatory activity.

PURPOSE

This study aimed to investigate the molecular mechanisms underlying the therapeutic efficacy of PSO and ASO in experimental ulcerative colitis (UC) with reference to sulfasalazine (SLZ).

METHODS

Eighty male albino rats were divided equally into 8 groups; Normal, PSO, ASO, SLZ, UC-control, (UC + PSO), (UC + ASO) and (UC + SLZ) groups. Colitis was induced by intra-rectal injection of acetic acid. PSO (0.5ml/200g), ASO (1ml/250g) and SLZ (100 mg/kg) were administered orally once/day for 14 days, 24h after colitis induction. Colitis was evaluated by measuring disease activity index (DAI), colon weight/length ratio and histologic inflammatory score. Vascular endothelial growth factor receptor-2 (VEGFR-2), colonic macrophage migration inhibitory factor (MIF), and malondialdehyde (MDA) were determined. Colonic gene expression of TNF-α, VEGF and heme oxygenase-1 (HO-1) were also estimated.

RESULTS

PSO and ASO treatments to UC rats significantly reduced DAI, weight/length ratio, VEGFR-2, and colon histologic inflammatory score versus UC-controls. ASO significantly suppressed MIF levels and TNF-α expression greater than PSO. However, PSO was more significant than ASO in reducing MDA levels and up-regulating HO-1 expression. Both oils significantly down-regulated VEGF expression. The obtained biochemical and histological changes induced by UC were nearly corrected by SLZ.

CONCLUSION

The proved beneficial effect of PSO and ASO as anti-inflammatory, anti-angiogenic, and antioxidant in UC rats could be mediated by suppression of TNF-α, VEGF, and MIF and up-regulation of HO-1.

Anti-ulcerative colitis effects of chemically characterized extracts from Calliandra haematocephala in acetic acid-induced ulcerative colitis

Background: Ulcerative colitis is a chronic immune-mediated inflammatory bowel disease that involves inflammation and ulcers of the colon and rectum. To date, no definite cure for this disease is available. Objective: The objective of the current study was to assess the effect of Calliandra haematocephala on inflammatory mediators and oxidative stress markers for the exploration of its anti-ulcerative colitis activity in rat models of acetic acid-induced ulcerative colitis. Methods: Methanolic and n-hexane extracts of areal parts of the plant were prepared by cold extraction method. Phytochemical analysis of both extracts was performed by qualitative analysis, quantitative methods, and high-performance liquid chromatography (HPLC). Prednisone at 2 mg/kg dose and plant extracts at 250, 500, and 750 mg/kg doses were given to Wistar rats for 11 days, which were given acetic acid on 8th day through the trans-rectal route for the induction of ulcerative colitis. A comparison of treatment groups was done with a normal control group and a colitis control group. To evaluate the anti-ulcerative colitis activity of Calliandra haematocephala, different parameters such as colon macroscopic damage, ulcer index, oxidative stress markers, histopathological examination, and mRNA expression of pro and anti-inflammatory mediators were evaluated. mRNA expression analysis was carried out by reverse transcription quantitative real-time polymerase chain reaction (RT-qPCR). Results: The phytochemical evaluation revealed polyphenols, flavonoids, tannins, alkaloids, and sterols in both extracts of the plant. Results of the present study exhibited that both extracts attenuated the large bowel inflammation and prevented colon ulceration at all tested doses. Macroscopic damage and ulcer scoreswere significantly decreased by both extracts. Malondialdehyde (MDA) levels and nitrite/nitrate concentrations in colon tissues were returned to normal levels while superoxide dismutase (SOD) activity was significantly improved by all doses. Histopathological examination exhibited that both extracts prevented the inflammatory changes, cellular infiltration, and colon thickening. Gene expression analysis by RT-qPCR revealed the downregulation of pro-inflammatory markers such as tumor necrosis factor-alpha (TNF-α) and cyclooxygenase-2 (COX-2) whereas the anti-inflammatory cytokines including Interleukin-4 (IL-4) and Interleukin-10 (IL-10) were found to be upregulated in treated rats. Conclusion: It was concluded based on study outcomes that methanolic and n-hexane extracts of Calliandra haematocephala exhibited anti-ulcerative colitis activity through modulation of antioxidant defense mechanisms and the immune system. In this context, C. haematocephala can be considered as a potential therapeutic approach for cure of ulcerative colitis after bioassay-directed isolation of bioactive phytochemicals and clinical evaluation.

Phytochemical analysis of Origanum majorana L. extract and investigation of its antioxidant, anti-inflammatory and immunomodulatory effects against experimentally induced colitis downregulating Th17 cells

ETHNOPHARMACOLOGICAL RELEVANCE

Origanum majorana L. is a member of the Lamiaceae family and is commonly used in Egyptian cuisine as a seasoning and flavor enhancer. It is also recognized as a well-known traditional medicine in Egypt and is widely used for treating abdominal colic due to its antispasmodic properties. However, the protective effects of Origanum majorana L. against ulcerative colitis and its underlying mechanisms remain unclear.

AIM OF THE STUDY

This study aimed to identify the biologically active components present in methanol extracts of Origanum majorana L. using gas chromatography/mass spectrometry (GC/MS). Additionally, it aimed to investigate the therapeutic effects of these extracts on acetic acid-induced ulcerative colitis and elucidate the potential mechanisms involved.

MATERIALS AND METHODS

We conducted a GC-MS analysis of the methanolic extract obtained from Origanum majorana L. Thirty-two male rats were included in the study and divided into four experimental groups, with eight rats in each group: sham, UC, UC + O. majorana, and UC sulfasalazine. After euthanizing the rats, colon tissue samples were collected for gross and microscopic examinations, assessment of oxidative stress, and molecular evaluation. GC-MS analysis identified 15 components in the extracts. Pretreatment with O. majorana L. extract and sulfasalazine significantly improved the disease activity index (DAI) and resulted in notable improvements in macroscopic and microscopic colon findings. Additionally, both treatments demonstrated preventive effects against colonic oxidative damage by reducing the levels of malondialdehyde (MDA) and increasing the levels of the antioxidant systems superoxide dismutase (SOD), catalase (CAT), and glutathione (GSH), which operate through the Nrf2/HO-1 signaling pathway. Moreover, these treatments downregulated the colonic inflammatory cascade by inhibiting NFκB, TNFα, IL-1β, IL6, IL23, IL17, COX-2, and iNOS, subsequently leading to downregulation of the JAK2/STAT3 signaling pathway and a decrease in the Th17 cell response. Furthermore, a reduction in the number of apoptotic epithelial cells that expressed caspase-3 was observed.

CONCLUSION

pretreatment with O. majorana L. extract significantly ameliorated acetic acid-induced ulcerative colitis. This effect could be attributed to the protective, antioxidant, anti-inflammatory, and anti-apoptotic properties of the extract.

Canagliflozin ameliorates ulcerative colitis via regulation of TLR4/MAPK/NF-κB and Nrf2/PPAR-γ/SIRT1 signaling pathways

Ulcerative colitis (UC) is one of the most common subtypes of inflammatory bowel disease (IBD) that affects the colon and is characterized by severe intestinal inflammation. Canagliflozin is a widely used antihyperglycemic agent, a sodium-glucose cotransporter-2 (SGLT2) inhibitor that enhances urinary glucose excretion. This study aims to provide insights into the potential benefits of canagliflozin as a treatment for UC by addressing possible cellular signals. Acetic acid (AA; 4% v/v) was administered intrarectally to induce colitis. Canagliflozin is given orally at a dose of 10 mg/kg/day. Canagliflozin attenuates inflammation in AA-induced colitis, evidenced by significant and dose-dependently downregulation of p38 MAPK, NF-κB-p65, IKK, IRF3, and NADPH-oxidase as well as colonic levels of IL-6 and IL-1β and MPO enzymatic activity. Canagliflozin mitigates colonic oxidative stress by decreasing MDA content and restoring SOD enzymatic activities and GSH levels mediated by co-activating of Nrf2, PPARγ, and SIRT1 pathways. Moreover, an in-silico study confirmed that canagliflozin was specific to all target proteins in this study. Canagliflozin's binding affinity with its target proteins indicates and confirms its effectiveness in regulating these pathways. Also, network pharmacology analysis supported that canagliflozin potently attenuates UC via a multi-target and multi-pathway approach.

Melatonin alleviates particulate matter-induced liver fibrosis by inhibiting ROS-mediated mitophagy and inflammation via Nrf2 activation

OBJECTIVE

Fine particulate matter (PM2.5) is a source of pollution worldwide, that causes inflammation and liver fibrosis. Melatonin, as the predominant hormone secreted by the pineal gland, can inhibit PM2.5-induced lung injury by activating nuclear factor erythroid 2-related factor 2 (Nrf2) to inhibit ferroptosis. However, the possible role of melatonin in PM2.5-induced liver damage remains unclear.

EXPERIMENTAL APPROACH

In vitro, the effects of melatonin on PM2.5-induced oxidative stress and LX-2 cell activation were examined. In vivo, a PM2.5-induced inflammation and liver fibrosis mouse model was used to evaluate the hepatoprotective effect of melatonin.

RESULTS

In vitro, melatonin induced the expression of Nrf2 and its downstream genes and inhibited PM2.5-induced reactive oxygen species (ROS) production and mitochondrial damage. Melatonin also ameliorated the PM2.5-induced oxidative stress and fibrogenic marker upregulation. However, the antifibrotic effect of melatonin was abolished in siNrf2-treated LX-2 cells. In vivo, we observed mitochondrial abnormalities and mitochondrial fragmentation, which were accompanied by increased PTEN-induced kinase 1 (PINK1) and Parkin expression, in PM2.5-treated mouse hepatocytes. These changes were partially reversed by melatonin. In addition, melatonin activated the Nrf2 signaling pathway and protected against PM2.5-induced oxidative stress. Furthermore, melatonin alleviated inflammation and liver fibrosis. Moreover, Nrf2-KO mice exhibited more severe inflammation and liver fibrosis after PM2.5 exposure than wild-type mice, and the protective effect of melatonin on PM2.5- treated Nrf2-KO mice was greatly compromised.

CONCLUSION

These data suggest that melatonin effectively inhibits PM2.5-induced liver fibrosis by activating Nrf2 and inhibiting ROS-mediated mitophagy and inflammation.

Ferulic acid ameliorates ulcerative colitis in a rat model via the inhibition of two LPS-TLR4-NF-κB and NF-κB-INOS-NO signaling pathways and thus alleviating the inflammatory, oxidative and apoptotic conditions in the colon tissue

INTRODUCTION

Ulcerative colitis is a chronic inflammation of the colon. However, the common treatment for it is accompanied by many complications. Therefore, the present study was aimed to determine the ameliorative effects of ferulic acid on acetic acid-induced colitis in rat.

MATERIALS AND METHODS

To induce ulcerative colitis, animals received 0.8 ml of 7% acetic acid intra-rectally. Ferulic acid in 20, 40, and 60 mg/kg doses was administered orally one hour after the ulcerative colitis induction. Animals received treatments for five consecutive days and then were euthanized on the sixth day. The colon was dissected out and macroscopic lesions were examined. Colon samples were evaluated for histopathological examination, biochemical analysis, determination of the expression of inflammatory, and apoptotic genes as well as total antioxidant capacity.

RESULTS

Ferulic acid significantly inhibited inflammatory and apoptotic genes mRNA expression, also production of MDA and NO. Ferulic acid significantly increased the activity of antioxidant factors (TAC content, and SOD and CAT activity), thereby preventing inflammation and histopathological damage in the colon tissue of colitis rats.

CONCLUSION

The results of the present study confirmed the antioxidant, anti-inflammatory, and anti-apoptotic properties of ferulic acid. About the mechanism of action of this compound, it can be concluded that the ability of ferulic acid in the amelioration of ulcerative colitis is related to the inhibition of two LPS-TLR4-NF-κB and NF-κB-INOS-NO signaling pathways.

Genistein and/or sulfasalazine ameliorate acetic acid-induced ulcerative colitis in rats via modulating INF-γ/JAK1/STAT1/IRF-1, TLR-4/NF-κB/IL-6, and JAK2/STAT3/COX-2 crosstalk

Ulcerative Colitis (UC) is a chronic idiopathic inflammatory bowel disease in which the colon's lining becomes inflamed. Exploring herbal remedies that can recover mucosal damage is becoming popular in UC. The study aims to investigate the probable colo-protective effect of a natural isoflavone, genistein (GEN), and/or a drug, sulfasalazine (SZ), against acetic acid (AA)-induced UC in rats, in addition to exploring the possible underlying mechanisms. UC was induced by the intrarectal installation of 1-2 ml of 5% diluted AA for 24 hours. Ulcerated rats were allocated into the disease group and three treated groups, with SZ (100 mg/kg), GEN (100 mg/kg), and their combination for 14 days, besides the control groups. The anti-colitic efficacy of GEN and/or SZ was evidenced by hindering the AA-induced weight loss, colon edema, and macroscopic scores, besides reduced disease activity index and weight/length ratio. Furthermore, treatments attenuated the colon histopathological injury scores, increased the number of goblet cells, and lessened fibrosis. Both treatments reduced the up-regulation of INF-γ/JAK1/STAT1 and INF-γ /TLR-4/ NF-κB signaling pathways and modulated the IRF-1/iNOS/NO and IL-6/JAK2/STAT3/COX-2 pathways and consequently, reduced the levels of TNF-α and IL-1β. Moreover, both treatments diminished oxidative stress, which appeared by reducing the MPO level and elevating the SOD activity, and hindered apoptosis; by decreasing the immunohistochemical expression of caspase-3. The current findings offer novel insights into the protective effects of GEN and suggest a superior benefit of combining GEN with SZ, over either drug alone, in the UC management.

Samarcandin protects against testicular ischemia/reperfusion injury in rats via activation of Nrf2/HO-1-mediated antioxidant responses

The purpose of this study was to evaluate the effectiveness of samarcandin (SMR) in preventing testicular injury caused by ischemia/reperfusion (I/R) in rats. Rats were divided into 4 groups at random: the sham group, the T/D control group (CONT), the T/D group receiving SMR treatment at 10 mg/kg (SMR-10), and the T/D group receiving SMR treatment at 20 mg/kg (SMR-20). When compared to the CONT group, SMR improved the oxidant/antioxidant balance by reducing malondialdehyde (MDA), nitric oxide (NOx), and increasing reduced glutathione (GSH), gluta-thione peroxide (GSH-Px), and superoxide dismutase (SOD). Moreover, SMR increased the levels of the steroid hormones' testosterone (TST), follicle-stimulating hormone (FSH), and luteinizing hormone (LH) in the blood as well as controlled the inflammatory mediators; interleukin-6 (IL6), tumor necrosis factor alpha (TNF-α), and nuclear factor κB (NF-κB). Nevertheless, SMR-treated animals showed a considerable downregulation of the apoptotic marker caspase-3. The T/D-induced histopathological changes were reduced and Proliferating Cell Nuclear Antigen (PCNA) protein expression was enhanced by SMR. These effects are associated with upregulation of testicular (Nuclear factor erythroid 2-related factor 2 (Nrf2), Heme oxygenase-1 (HO-1), and downregulation of NF-κB mRNA expression levels. These findings suggest that SMR may be able to prevent T/D-induced testis damage by mainly regulating the expression of Nrf2 and NF-B, which seems to mediate its promising antioxidant, anti-inflammatory and antiapoptotic effects seen in this study.

ERBB2-PTGS2 axis promotes intervertebral disc degeneration by regulating senescence of nucleus pulposus cells

Intervertebral disc degeneration (IDD) is considered one of the main causes of low back pain and lumbar disc herniation. Various studies have shown that disc cell senescence plays a critical role in this process. however, its role in IDD is yet unclear. In this study, we explored the role of senescence-related genes (SR-DEGs) and its underlying mechanism in IDD. A total of 1325 differentially expressed genes (DEGs) were identified using Gene Expression Omnibus (GEO) database GSE41883. 30 SR-DEGs were identified for further functional enrichment and pathway analysis, and two hub SR-DEGs (ERBB2 and PTGS2) were selected to construct transcription factor (TF)-gene interaction and TF-miRNA coregulatory networks, and 10 candidate drugs were screened for the treatment of IDD. Last but not least, in vitro experiments show that ERBB2 expression decreased and PTGS2 expression increased in human nucleus pulposus (NP) cell senescence model treated with TNF-α. After lentivirus-mediated overexpression of ERBB2, the expression of PTGS2 decreased and the senescence level of NP cells decreased. Overexpression of PTGS2 reversed the anti-senescence effects of ERBB2. The findings in this study suggested that ERBB2 overexpression further reduced NP cell senescence by inhibiting PTGS2 levels, which ultimately alleviated IDD. Taken together, our findings provide new insights into the roles of senescence-related genes in IDD and highlight a novel target of ERBB2-PTGS2 axis for therapeutic strategies.

Dimethyl Fumarate and Intestine: From Main Suspect to Potential Ally against Gut Disorders

Dimethyl fumarate (DMF) is a well-characterized molecule that exhibits immuno-modulatory, anti-inflammatory, and antioxidant properties and that is currently approved for the treatment of psoriasis and multiple sclerosis. Due to its Nrf2-dependent and independent mechanisms of action, DMF has a therapeutic potential much broader than expected. In this comprehensive review, we discuss the state-of-the-art and future perspectives regarding the potential repurposing of DMF in the context of chronic inflammatory diseases of the intestine, such as inflammatory bowel disorders (i.e., Crohn's disease and ulcerative colitis) and celiac disease. DMF's mechanisms of action, as well as an exhaustive analysis of the in vitro/in vivo evidence of its beneficial effects on the intestine and the gut microbiota, together with observational studies on multiple sclerosis patients, are here reported. Based on the collected evidence, we highlight the new potential applications of this molecule in the context of inflammatory and immune-mediated intestinal diseases.

The coumaric acid and syringic acid ameliorate acetic acid-induced ulcerative colitis in rats via modulator of Nrf2/HO-1 and pro-inflammatory cytokines

BACKGROUND

Ulcerative colitis (UC) is an inflammatory bowel disease (IBD) that causes uncontrolled inflammation and ulcers in your digestive tract. The coumaric acid and syringic acid are phenolic derivative found in many fruits and vegetables and is widely recognized for the ability of anti-parasitic, anti-microbial, anti-viral, anti-inflammatory, and antioxidant. The purpose of this study was to investigate the anti-inflammatory and antioxidant properties of coumaric acid and syringic acid on acetic acid-induced colitis in rats.

METHODS

A total of 64 male Wistar rats were divided into eight equal groups (n = 8). Colitis was induced by intrarectal administration of acetic acid, and rats orally received coumaric acid (100 and 150 mg/kg), syringic acid (10, 25, and 50 mg/kg), and dexamethasone (2 mg/kg) once per day for four days after colitis induction. Then, HO-1, Nrf2, and NQO1 mRNA expression were quantified by real time-PCR. Finally, the tissue levels of TNF-α and IL-1β protein were measured by ELISA.

RESULTS

Colitis led to a decrease in HO-1, Nrf2, and NQO1 mRNA expression and an increase in the tissue levels of TNF-α and IL-1β protein in the colon tissue. Treatment with dexamethasone significantly increased HO-1, Nrf2, and NQO1 mRNA expression and decreased the tissue levels of TNF-α and IL-1β protein compared to the UC group. Treatment with 150 mg/kg of coumaric acid and 50 mg/kg of syringic acid significantly increased HO-1, Nrf2, and NQO1 mRNA expression compared to the UC group. Also, treatment with 100 and 150 mg/kg of coumaric acid and 10, 25, and 50 mg/kg of syringic acid significantly decreased the tissue levels of TNF-α and IL-1β protein compared to the UC group.

CONCLUSION

The coumaric acid and syringic acid, especially at high doses, may be an alternative strategy for the treatment of UC by the reduction of TNF-α and IL-1β levels and upregulation of the Nrf2/HO-1 pathway.

Carbocisteine as a Modulator of Nrf2/HO-1 and NFκB Interplay in Rats: New Inspiration for the Revival of an Old Drug for Treating Ulcerative Colitis

Ulcerative colitis (UC), an inflammatory bowel disease, is a chronic condition of a multifaceted pathophysiology. The incidence of UC is increasing internationally. The current therapies for UC lack relative effectiveness and are associated with adverse effects. Therefore, novel therapeutic options should be developed. It has been well documented that modulating the Nrf2/NFκB is a promising therapeutic target in inflammation. Carbocisteine is a mucoregulatory medication and its efficacy in COPD was found to be more closely related to its antioxidant and anti-inflammatory properties. Carbocisteine has not yet been examined for the management of UC. Hence, our approach was to investigate the potential coloprotective role of carbocisteine in acetic acid-induced colitis in rats. Our results revealed that carbocisteine improved colon histology and macroscopic features and subdued the disease activity as well. Additionally, carbocisteine attenuated colon shortening and augmented colon antioxidant defense mechanisms via upregulating catalase and HO-1 enzymes. The myeloperoxidase activity was suppressed indicating inhibition of the neutrophil infiltration and activation. Consistent with these findings, carbocisteine boosted Nrf2 expression along with NFκB inactivation. Consequently, carbocisteine downregulated the proinflammatory cytokines IL-6 and TNF-α and upregulated the anti-inflammatory cytokine IL-10. Concomitant to these protective roles, carbocisteine displayed anti-apoptotic properties as revealed by the reduction in the Bax: BCL-2 ratio. In conclusion, carbocisteine inhibited oxidative stress, inflammatory response, and apoptosis in acetic acid-induced UC by modulating the Nrf2/HO-1 and NFκB interplay in rats. Therefore, the current study provides a potential basis for repurposing a safe and a commonly used mucoregulator for the treatment of UC.

D-Carvone Attenuates CCl4-Induced Liver Fibrosis in Rats by Inhibiting Oxidative Stress and TGF-ß 1/SMAD3 Signaling Pathway

D-carvone is a natural monoterpene found in abundance in the essential oil of aromatic medicinal plants with a wide range of pharmacological values. However, the impact of D-carvone on liver fibrosis remains unclear. This study aimed to evaluate the anti-fibrotic potential of D-carvone in a rat model of liver fibrosis and to clarify the possible underlying mechanisms. Liver fibrosis was induced in rats by carbon tetrachloride, CCl₄ (2.5 mL/kg, interperitoneally every 72 h for 8 weeks). Oral treatment of rats with D-carvone (50 mg/kg, daily) started on the 3rd week of CCl₄ administration. D-carvone significantly enhanced liver functions (ALT, AST), oxidant/antioxidant status (MDA, SOD, GSH, total antioxidant capacity; TAC), as well as histopathological changes. Moreover, D-carvone effectively attenuated the progression of liver fibrosis, evident by the decreased collagen deposition and fibrosis score by Masson trichrome staining (MT) and α-SMA protein expression. Moreover, D-carvone administration resulted in a significant downregulation of the pro-fibrogenic markers TGF-β1 and SMAD3 and upregulation of MMP9. These findings reveal the anti-fibrotic effect of D-carvone and suggest regulation of the TGF-β1/SMAD3 pathway, together with the antioxidant activity as a mechanistic cassette, underlines this effect. Therefore, D-carvone could be a viable candidate for inhibiting liver fibrosis and other oxidative stress-related hepatic diseases. Clinical studies to support our hypothesis are warranted.