Curative effects of fucoidan on acetic acid induced ulcerative colitis in rats via modulating aryl hydrocarbon receptor and phosphodiesterase-4

MIIST305 mitigates gastrointestinal acute radiation syndrome injury and ameliorates radiation-induced gut microbiome dysbiosis

High-dose radiation exposure results in gastrointestinal (GI) acute radiation syndrome identified by the destruction of mucosal layer, intestinal growth barrier dysfunction, and aberrant inflammatory responses. Further, radiation causes gut microbiome dysbiosis characterized by diminished microbial diversity, mostly commensal bacteria, and the spread of bacterial pathogens that trigger the recruitment of immune cells and the production of pro-inflammatory factors that lead to further GI tissue damage. Currently, there are no U.S. Food and Drug Administration (FDA) approved countermeasures that can treat radiation-induced GI injuries. To meet this critical need, Synedgen Inc. has developed a glycopolymer radiomitigator (MIIST305) that is specifically targeted to the GI tract, which acts by intercalating into the mucus layer and the glycocalyx of intestinal epithelial cells that could potentially ameliorate the deleterious effects of radiation. Male C57BL/6J adult mice were exposed to 13 Gy partial body X-irradiation with 5% bone marrow shielding and MIIST305 was administered on days 1, 3, and 5 post-irradiation. Approximately 85% of the animals survived the irradiation exposure and were apparently healthy until the end of the 30-day study period. In contrast, no control, Vehicle-treated animals survived past day 10 at this radiation dose. We show that MIIST305 improved intestinal epithelial barrier function and suppressed systemic inflammatory responses mediated by radiation-induced pro-inflammatory cytokines. Taxonomic profiling and community structure of the fecal and colonic mucosa microbiota demonstrated that MIIST305 treatment increased microbial diversity and restored abundance of beneficial commensal bacteria, including Lactobacillus and Bifidobacterium genera while suppressing potentially pathogenic bacteria Enterococcus and Staphylococcus compared with Vehicle-treated animals. In summary, MIIST305 is a novel GI-targeted therapeutic that greatly enhances survival in mice exposed to lethal radiation and protects the GI tract from injury by restoring a balanced gut microbiota and reducing pro-inflammatory responses. Further development of this drug as an FDA-approved medical countermeasure is of critical importance.

Combining vinpocetine or cocoa with levodopa, Coenzyme Q10 and vitamin B complex mitigates rotenone-induced Parkinson's disease in rats: Impact on Nrf2/HO-1, NF-kB, AMPK/SIRT-1/Beclin-1, AKT/GSK-3β/CREB/BDNF and Apoptotic Pathways

There are no curative treatments for Parkinson's disease (PD), and current treatments focus on symptomatic management. This study aimed to investigate the beneficial effects of combining L-DOPA/Carbidopa with essential cofactors (vitamin (VIT) B complex and coenzyme Q10 (CoQ10)), alone or in conjunction with vinpocetine (VIN) or cocoa, as a potential strategy to enhance neuroprotection in rotenone (RT)-induced PD rat model, highlighting mechanistic insights into their underlying neuroprotective mechanisms and focusing on addressing oxidative stress, inflammation, autophagy, and apoptosis. These combinations were tested on adult male Wistar rats allocated into six groups. Group I received saline (normal control), while groups II-VI were injected with RT for 19 days to induce PD. Group II received RT alone, group III received daily oral L-DOPA/Carbidopa, and groups IV-VI received L-DOPA/Carbidopa with VIT B complex and CoQ10, either alone (Group IV) or combined with cocoa (Group V) or VIN (Group VI). These treatments markedly improved RT-induced perturbations in locomotor and cognitive outcomes; neurotransmitters' levels; oxidative stress (Nrf2/HO-1, MDA, INOS, SOD and TAC); inflammatory (NF-κB, TNF-α, IL-1β, GFAP and COX-2); neurotrophic (AKT/CREB/BDNF); apoptotic (BAX, caspase-3, AIF, and Bcl-2); and autophagic (AMPK/SIRT-1/Beclin-1) biomarkers; histopathological findings and tyrosine hydroxylase (TH) immunoexpression. Furthermore, the best outcomes were observed in cocoa and VIN combinations. These results indicated that combining L-DOPA with CoQ10 and VIT B complex in conjunction with either VIN or cocoa could provide a potential strategy for managing motor impairments and preventing neurodegeneration in PD. The interaction between key signaling pathways, including Nrf2/HO-1, NF-kB, AMPK/SIRT-1, and AKT/GSK-3β/CREB/BDNF, likely mediates this effect. However, further clinical validation is required to assess this approach's real-world applicability and therapeutic potential.

Anti-Inflammatory Effects of Algae-Derived Biomolecules in Gut Health: A Review

Under physiological conditions, the inflammatory response acts as a biological defense against tissue damage or infection, and is rapidly resolved once the infection is cleared. However, chronic inflammatory diseases, including inflammatory bowel disease (IBD), have become increasingly widespread in the last decades, placing a burden on the quality of life of affected people and on healthcare systems worldwide. Available drug therapies are often ineffective due to the chronic nature of these diseases, and prolonged administration of drugs can result in severe side effects for the patient or a lack of efficacy. In addition, there is the growing problem of bacterial resistance to synthetic antibiotics. Together, these factors have led to a strong research focus on the discovery of natural products capable of treating IBD. Recently, there has been a growing interest in compounds derived from marine sources, mainly algae, due to their bioactive secondary metabolites with anti-inflammatory properties well known in the literature. Based on this evidence, this review aimed to evaluate the anti-inflammatory potential of algae-derived biomolecules in IBD. In particular, interesting species from green algae (e.g., Chlorella vulgaris and Ulva pertusa), brown algae (e.g., Macrocystis pyrifera and Ecklonia cava) and red algae (e.g., Porphyra tenera and Grateloupia turuturu) are included in this review due to their proven anti-inflammatory properties. For this purpose, an extensive literature search was conducted using several databases. The results suggest that both macroalgae and microalgae have remarkable potential for IBD therapy due to the anti-inflammatory and antioxidant activities of their bioactive compounds. However, while the preclinical evidence is encouraging, further and long-term clinical studies are needed to better understand their mechanisms of action in order to determine the true efficacy of marine algae in the treatment of IBD.

Ferulic acid inhibits tumor proliferation and attenuates inflammation of hepatic tissues in experimentally induced HCC in rats

Hepatocellular carcinoma (HCC) is a prevalent form of primary liver cancer with a 5-year survival rate of just 18%. Ferulic acid, a natural compound found in fruits and vegetables such as sweet corn, rice bran, and dong quai, is an encouraging drug known for its diverse positive effects on the body, including anti-inflammatory, anti-apoptotic, and neuroprotective properties. Our study aimed to investigate the potential antitumor effects of ferulic acid to inhibit tumor growth and inflammation of HCC in rats. HCC was induced in rats by administering thioacetamide. Additionally, some rats were given 50 mg/kg of ferulic acid three times a week for 16 weeks. Liver function was assessed by measuring serum alpha-fetoprotein (AFP) and examining hepatic tissue sections stained with hematoxylin/eosin or anti-hypoxia induced factor-1α (HIF-1α). The hepatic mRNA and protein levels of HIF-1α, nuclear factor κB (NFκB), tumor necrosis factor-α (TNF-α), mammalian target of rapamycin (mTOR), signal transducer and activator of transcription 3 (STAT3), cMyc, and cyclin D1 were examined. The results showed that ferulic acid increased the rats' survival rate by reducing serum AFP levels and suppressing hepatic nodules. Furthermore, ferulic acid ameliorated the appearance of vacuolated cytoplasm induced by HCC, reduced apoptotic nuclei, and necrotic nodules. Finally, ferulic acid decreased the expression of HIF-1α, NFκB, TNF-α, mTOR, STAT3, cMyc, and cyclin D1. In conclusion, ferulic acid is believed to possess antitumor properties by inhibiting HCC-induced hypoxia through the suppression of HIF-1α expression. Additionally, it helps in reducing the expression of mTOR, STAT3, cMyc, and cyclin D1, thereby slowing down tumor growth. Lastly, ferulic acid reduced hepatic tissue inflammation by downregulating NFκB and TNF-α.

Evaluating anticancer activity of emodin by enhancing antioxidant activities and affecting PKC/ADAMTS4 pathway in thioacetamide-induced hepatocellular carcinoma in rats

Emodin is a naturally occurring anthraquinone derivative with a wide range of pharmacological activities, including neuroprotective and anti-inflammatory activities. We aim to assess the anticancer activity of emodin against hepatocellular carcinoma (HCC) in rat models using the proliferation, invasion, and angiogenesis biomarkers. After induction of HCC, assessment of the liver impairment and the histopathology of liver sections were investigated. Hepatic expression of both mRNA and protein of the oxidative stress biomarkers, HO-1, Nrf2; the mitogenic activation biomarkers, ERK5, PKCδ; the tissue destruction biomarker, ADAMTS4; the tissue homeostasis biomarker, aggregan; the cellular fibrinolytic biomarker, MMP3; and of the cellular angiogenesis biomarker, VEGF were measured. Emodin increased the survival percentage and reduced the number of hepatic nodules compared to the HCC group. Besides, emodin reduced the elevated expression of both mRNA and proteins of all PKC, ERK5, ADAMTS4, MMP3, and VEGF compared with the HCC group. On the other hand, emodin increased the expression of mRNA and proteins of Nrf2, HO-1, and aggrecan compared with the HCC group. Therefore, emodin is a promising anticancer agent against HCC preventing the cancer prognosis and infiltration. It works through many mechanisms of action, such as blocking oxidative stress, proliferation, invasion, and angiogenesis.

MIIST305 mitigates gastrointestinal acute radiation syndrome injury and ameliorates radiation-induced gut microbiome dysbiosis

High-dose radiation exposure results in gastrointestinal (GI) acute radiation syndrome identified by the destruction of mucosal layer, intestinal epithelial barrier dysfunction, and aberrant inflammatory responses. In addition, radiation causes gut microbiome dysbiosis characterized by diminished microbial diversity, reduction in the abundance of beneficial commensal bacteria, and the spread of bacterial pathogens that trigger the recruitment of immune cells and the production of pro-inflammatory factors that lead to further GI tissue damage. Currently, there are no FDA-approved countermeasures that can treat radiation-induced GI injury. To meet this critical need, Synedgen Inc., has developed a glycopolymer radiomitigator (MIIST305) that is specifically targeted to the GI tract which acts by intercalating into the mucus layer and the glycocalyx of intestinal epithelial cells that could potentially ameliorate the deleterious effects of radiation. Male C57BL/6J adult mice were exposed to 13 Gy total body X-irradiation with 5% bone marrow shielding and MIIST305 was administered on days 1, 3, and 5 post-irradiation. Approximately 85% of the animals survived the irradiation exposure and were apparently healthy until the end of the 30-day study period. In contrast, no control, vehicle-treated animals survived past day 10 at this radiation dose. We show that MIIST305 improved intestinal epithelial barrier function and suppressed systemic inflammatory response mediated by radiation-induced pro-inflammatory cytokines. Taxonomic profiling and community structure of the fecal and colonic mucosa microbiota demonstrated that MIIST305 treatment increased microbial diversity and restored abundance of beneficial commensal bacteria, including Lactobacillus and Bifidobacterium genera, while suppressing potentially pathogenic bacteria compared with vehicle-treated animals. In summary, MIIST305 is a novel GI-targeted therapeutic that greatly enhances survival in mice exposed to lethal radiation and protects the GI tract from injury by restoring a balanced gut microbiota and effectively reducing proinflammatory responses. Further development of this drug as an FDA-approved medical countermeasure will be of critical importance in the event of a radiation public health emergency.

Cyclic adenosine 3', 5'-monophosphate (cAMP) signaling is a crucial therapeutic target for ulcerative colitis

The pathogenesis of ulcerative colitis (UC), a chronic intestine inflammatory disease primarily affecting adolescents, remains uncertain. Contemporary studies suggest that a confluence of elements, including genetic predispositions, environmental catalysts, dysregulated immune responses, and disturbances in the gut microbiome, are instrumental in the initiation and advancement of UC. Among them, inflammatory activation and mucosal barrier damage caused by abnormal immune regulation are essential links in the development of UC. The impairment of the mucosal barrier is intricately linked to the interplay of various cellular mechanisms, including oxidative stress, autophagy, and programmed cell death. An extensive corpus of research has elucidated that level of cyclic adenosine 3',5'-monophosphate (cAMP) undergo modifications in the midst of inflammation and participate in a diverse array of cellular operations that mitigate inflammation and the impairment of the mucosal barrier. Consequently, a plethora of pharmacological agents are currently under development, with some advancing through clinical trials, and are anticipated to garner approval as novel therapeutics. In summary, cAMP exerts a crucial influence on the onset and progression of UC, with fluctuations in its activity being intimately associated with the severity of the disease's manifestation. Significantly, this review unveils the paramount role of cAMP in the advancement of UC, offering a tactical approach for the clinical management of individuals afflicted with UC.

Therapeutic effect of oral insulin-chitosan nanobeads pectin-dextrin shell on streptozotocin-diabetic male albino rats

The current study inspects the therapeutic effects of orally ingested insulin-loaded chitosan nanobeads (INS-CsNBs) with a pectin-dextrin (PD) coating on streptozotocin (STZ)-induced diabetes in Wistar rats. The study also assessed antioxidant effects in pancreatic tissue homogenate, insulin, C-peptide, and inflammatory markers interleukin-1 beta and interleukin-6 (IL-1β and IL-6) in serum. Additionally, histopathological and immunohistochemical examination of insulin granules, oxidative stress, nuclear factor kappa B (NF-κB P65), and sirtuin-1 (SIRT-1) protein detection, as well as gene expression of nuclear factor erythroid 2-related factor 2 (Nrf2), heme oxygenase-1 (HO-1), B-cell lymphoma 2 (Bcl2), and Bcl-2-associated X protein (Bax) in pancreatic tissue were investigated. After induction of diabetes with STZ, rats were allocated into 6 groups: the normal control (C), the diabetic control (D), and the diabetic groups treated with INS-CsNBs coated with PD shell (50 IU/kg) (NF), free oral insulin (10 IU/kg) (FO), CsNBs-PD shell (50 IU/kg) (NB), and subcutaneous insulin (10 IU/kg) (Sc). The rats were treated daily for four weeks. Treatment of diabetic rats with INS-CsNBs coated with PD shell resulted in a significant improvement in blood glucose levels, elevated antioxidant activities, decreased NF-κB P65, IL-1β, and IL-6 levels, upregulated Nrf-2 and HO-1, in addition to a marked improvement in the histological architecture and integrity compared to the diabetic group. The effects of oral INS-CsNBs administration were comparable to those of subcutaneous insulin. In conclusion, oral administration of INS-loaded Cs-NBs with a pectin-dextrin shell demonstrated an ameliorative effect on STZ-induced diabetes, avoiding the drawbacks of subcutaneous insulin.

Research progress in the treatment of inflammatory bowel disease with natural polysaccharides and related structure-activity relationships

Inflammatory bowel disease (IBD) comprises a group of highly prevalent and chronic inflammatory intestinal tract diseases caused by multiple factors. Despite extensive research into the causes of the disease, IBD's pathogenic mechanisms remain unclear. Moreover, side effects of current IBD therapies restrict their long-term clinical use. In contrast, natural polysaccharides exert beneficial anti-IBD effects and offer advantages over current anti-IBD drugs, including enhanced safety and straightforward isolation from abundant and reliable sources, and thus may serve as components of functional foods and health products for use in IBD prevention and treatment. However, few reviews have explored natural polysaccharides with anti-IBD activities or the relationship between polysaccharide conformation and anti-IBD biological activity. Therefore, this review aims to summarize anti-IBD activities and potential clinical applications of polysaccharides isolated from plant, animal, microorganismal, and algal sources, while also exploring the relationship between polysaccharide conformation and anti-IBD bioactivity for the first time. Furthermore, potential mechanisms underlying polysaccharide anti-IBD effects are summarized, including intestinal microbiota modulation, intestinal inflammation alleviation, and intestinal barrier protection from IBD-induced damage. Ultimately, this review provides a theoretical foundation and valuable insights to guide the development of natural polysaccharide-containing functional foods and nutraceuticals for use as dietary IBD therapies.

Porcine Brain Enzyme Hydrolysate Enhances Immune Function and Antioxidant Defense via Modulation of Gut Microbiota in a Cyclophosphamide-Induced Immunodeficiency Model

This study examined how consuming porcine brain enzyme hydrolysate (PBEH) affects the immune function and composition of the gut microbiota in an immunodeficient animal model. Male Wistar rats aged 6 weeks were fed casein (control), 100 mg/kg body weight (BW), red ginseng extract (positive-control), and 6, 13, and 26 mg PBEH per kg BW (PBEH-L, PBEH-M, and PBEH-H, respectively) daily for 4 weeks. At 30 min after consuming assigned compounds, they were orally administered cyclophosphamide (CTX; 5 mg/kg BW), an immunosuppressive agent, to suppress the immune system by inhibiting the proliferation of lymphocytes. The normal-control rats were fed casein and water instead of CTX. Natural killer cell activity and splenocyte proliferation induced by 1 μg/mL lipopolysaccharide were lower in the control group than the normal-control group, and they significantly increased with PBEH consumption, particularly at high doses. The PBEH consumption increased dose-dependently in the Th1/Th2 ratio compared to the control. The lipid peroxide contents were lower in the PBEH group than in the control group. Moreover, PBEH m and PBEH-H consumption mitigated white pulp cell damage, reduced red pulp congestion, and increased spleen mast cells in the histological analysis. Intestinal microbiota composition demonstrated differences between the groups at the genus levels, with Akkermansia being more abundant in the control group than the normal-control group and the PBEH-H group showing a decrease. However, Bifidobacterium decreased in the control group but increased in the PBEH-H group. The β-diversity revealed distinct microbial communities of PBEH and positive-control groups compared to the control group (p < 0.05). The metagenome predictions revealed that PBEH-H influenced amino acid metabolism, antioxidant defense, insulin sensitivity, and longevity pathways. In conclusion, PBEH-H intake boosted immune responses and reduced lipid peroxides by modulating gut microbiota composition. These findings suggest that PBEH-H has the potential as a dietary supplement for improving immune function and gut health in individuals with immunodeficiency.

Therapeutic effects of genistein in experimentally induced ulcerative colitis in rats via affecting mitochondrial biogenesis

Ulcerative colitis (UC) is an inflammatory bowel disease that affects the mucosa of the colon, resulting in severe inflammation and ulcers. Genistein is a polyphenolic isoflavone present in several vegetables, such as soybeans and fava beans. Therefore, we conducted the following study to determine the therapeutic effects of genistein on UC in rats by influencing antioxidant activity and mitochondrial biogenesis and the subsequent effects on the apoptotic pathway. UC was induced in rats by single intracolonic administration of 2 ml of 4% acetic acid. Then, UC rats were treated with 25-mg/kg genistein. Colon samples were obtained to assess the gene and protein expression of nuclear factor erythroid 2-related factor-2 (Nrf2), heme oxygenase-1 (HO-1), peroxisome proliferator-activated receptor-gamma coactivator (PGC-1), mitochondrial transcription factor A (TFAM), B-cell lymphoma 2 (BCL2), BCL2-associated X (BAX), caspase-3, caspase-8, and caspase-9. In addition, colon sections were stained with hematoxylin/eosin to investigate the cell structure. The microimages of UC rats revealed inflammatory cell infiltration, hemorrhage, and the destruction of intestinal glands, and these effects were improved by treatment with genistein. Finally, treatment with genistein significantly increased the expression of PGC-1, TFAM, Nrf2, HO-1, and BCL2 and reduced the expression of BAX, caspase-3, caspase-8, and caspase-9. In conclusion, genistein exerted therapeutic effects against UC in rats. This therapeutic activity involved enhancing antioxidant activity and increasing mitochondrial biogenesis, which reduced cell apoptosis.

Short Chain Fatty Acids: Essential Weapons of Traditional Medicine in Treating Inflammatory Bowel Disease

Inflammatory bowel disease (IBD) is a chronic and recurrent intestinal inflammatory disease, mainly including Crohn's disease (CD) and ulcerative colitis (UC). In recent years, the incidence and prevalence of IBD have been on the rise worldwide and have become a significant concern of health and a huge economic burden on patients. The occurrence and development of IBD involve a variety of pathogenic factors. The changes in short-chain fatty acids (SCFAs) are considered to be an important pathogenic mechanism of this disease. SCFAs are important metabolites in the intestinal microbial environment, which are closely involved in regulating immune, anti-tumor, and anti-inflammatory activities. Changes in metabolite levels can reflect the homeostasis of the intestinal microflora. Recent studies have shown that SCFAs provide energy for host cells and intestinal microflora, shape the intestinal environment, and regulate the immune system, thereby regulating intestinal physiology. SCFAs can effectively reduce the incidence of enteritis, cardiovascular disease, colon cancer, obesity, and diabetes, and also play an important role in maintaining the balance of energy metabolism (mainly glucose metabolism) and improving insulin tolerance. In recent years, many studies have shown that numerous decoctions and natural compounds of traditional Chinese medicine have shown promising therapeutic activities in multiple animal models of colitis and thus attracted increasing attention from scientists in the study of IBD treatment. Some of these traditional Chinese medicines or compounds can effectively alleviate colonic inflammation and clinical symptoms by regulating the generation of SCFAs. This study reviews the effects of various traditional Chinese medicines or bioactive substances on the production of SCFAs and their potential impacts on the severity of colonic inflammation. On this basis, we discussed the mechanism of SCFAs in regulating IBD-associated inflammation, as well as the related regulatory factors and signaling pathways. In addition, we provide our understanding of the limitations of current research and the prospects for future studies on the development of new IBD therapies by targeting SCFAs. This review may widen our understanding of the effect of traditional medicine from the view of SCFAs and their role in alleviating IBD animal models, thus contributing to the studies of IBD researchers.

Therapeutic Effects of Arctiin on Alzheimer's Disease-like Model in Rats by Reducing Oxidative Stress, Inflammasomes and Fibrosis

BACKGROUND

Alzheimer's disease (AD) affects approximately 50 million people globally and is expected to triple by 2050. Arctiin is a lignan found in the Arctium lappa L. plant. Arctiin possesses anti-proliferative, antioxidative and anti-adipogenic.

OBJECTIVES

We aimed to explore the potential therapeutic effects of Arctiin on rats with AD by evaluating the expression of TLR4, NLRP3, STAT3, TGF-β, cyclin D1, and CDK2.

METHODS

AD was induced in rats by administering 70 mg/kg of aluminum chloride through intraperitoneal injection daily for six weeks. After inducing AD, some rats were treated with 25 mg/kg of Arctiin daily for three weeks through oral gavage. Furthermore, to examine the brain tissue structure, hippocampal sections were stained with hematoxylin/eosin and anti-TLR4 antibodies. The collected samples were analyzed for gene expression and protein levels of TLR4, NLRP3, STAT3, TGF-β, cyclin D1, and CDK2.

RESULTS

In behavioral tests, rats showed a significant improvement in their behavior when treated with Arctiin. Microimages stained with hematoxylin/eosin showed that Arctiin helped to improve the structure and cohesion of the hippocampus, which was previously impaired by AD. Furthermore, Arctiin reduced the expression of TLR4, NLRP3, STAT3, TGF-β, cyclin D1, and CDK2.

CONCLUSION

Arctiin can enhance rats' behavior and structure of the hippocampus in AD rats. This is achieved through its ability to reduce the expression of both TLR4 and NLRP3, hence inhibiting the inflammasome pathway. Furthermore, Arctiin can improve tissue fibrosis by regulating STAT3 and TGF-β. Lastly, it can block the cell cycle proteins cyclin D1 and CDK2.

Fucoidan's Molecular Targets: A Comprehensive Review of Its Unique and Multiple Targets Accounting for Promising Bioactivities Supported by In Silico Studies

Fucoidan is a class of multifunctional polysaccharides derived from marine organisms. Its unique and diversified physicochemical and chemical properties have qualified them for potential and promising pharmacological uses in human diseases, including inflammation, tumors, immunity disorders, kidney diseases, and diabetes. Physicochemical and chemical properties are the main contributors to these bioactivities. The previous literature has attributed such activities to its ability to target key enzymes and receptors involved in potential disease pathways, either directly or indirectly, where the anionic sulfate ester groups are mainly involved in these interactions. These findings also confirm the advantageous pharmacological uses of sulfated versus non-sulfated polysaccharides. The current review shall highlight the molecular targets of fucoidans, especially enzymes, and the subsequent responses via either the upregulation or downregulation of mediators' expression in various tissue abnormalities. In addition, in silico studies will be applied to support the previous findings and show the significant contributors. The current review may help in understanding the molecular mechanisms of fucoidan. Also, the findings of this review may be utilized in the design of specific oligomers inspired by fucoidan with the purpose of treating life-threatening human diseases effectively.

Lidocaine ameliorates intestinal barrier dysfunction in irritable bowel syndrome by modulating corticotropin-releasing hormone receptor 2

BACKGROUND

Intestinal barrier dysfunction is a prevalent pathogenic factor underlying various disorders. Currently there is no effective resolution. Previous studies have reported the potential anti-inflammatory properties of lidocaine and its ability to alleviate visceral hypersensitivity in individuals with irritable bowel syndrome (IBS). Therefore, our study will further verify the effect of lidocaine on intestinal barrier dysfunction in IBS and investigate the underlying mechanisms.

METHODS

In this study, we investigated the role of lidocaine by assessing visceral hypersensitivity, body weight, inflammatory factors, fluorescein isothiocyanate-dextran 4000 (FD4) flux, tight junctions (TJs) and spleen and thymus index in rats subjected to water avoidance stress (WAS) to mimic intestinal barrier dysfunction in IBS with and without lidocaine. In vitro, we investigated the role of corticotropin-releasing hormone receptor 2 (CRHR2) in lidocaine-treated Caco2 cells using small interfering RNA (siRNA) targeting CRHR2.

KEY RESULTS

In WAS rats, lidocaine significantly restored weight loss, damaged TJs, spleen index and thymus index and inhibited abdominal hypersensitivity as well as blood levels of markers indicating intestinal permeability, such as diamine oxidase (DAO), D-lactic acid (D-Lac) and lipopolysaccharide (LPS). Consequently, the leakage of FD4 flux from intestine was significantly attenuated in lidocaine group, and levels of intestinal inflammatory factors (IL-1β, IFN-γ, TNF-α) were reduced. Interestingly, lidocaine significantly suppressed corticotropin-releasing hormone (CRH) levels in lamina propria cells, while the CRH receptor CRHR2 was upregulated in intestinal epithelial cells. In vitro, lidocaine enhanced the expression of CRHR2 on Caco-2 intestinal epithelial cells and restored disrupted TJs and the epithelial barrier caused by LPS. Conversely, these effects were diminished by a CRHR2 antagonist and siRNA-CRHR2, suggesting that the protective effect of lidocaine depends on CRHR2.

CONCLUSIONS AND INFERENCES

Lidocaine ameliorates intestinal barrier dysfunction in IBS by potentially modulating the expression of CRHR2 on intestinal epithelial cells.

Anti-Inflammatory Effects of Bioactive Compounds from Seaweeds, Bryozoans, Jellyfish, Shellfish and Peanut Worms

Inflammation is a defense mechanism of the body in response to harmful stimuli such as pathogens, damaged cells, toxic compounds or radiation. However, chronic inflammation plays an important role in the pathogenesis of a variety of diseases. Multiple anti-inflammatory drugs are currently available for the treatment of inflammation, but all exhibit less efficacy. This drives the search for new anti-inflammatory compounds focusing on natural resources. Marine organisms produce a broad spectrum of bioactive compounds with anti-inflammatory activities. Several are considered as lead compounds for development into drugs. Anti-inflammatory compounds have been extracted from algae, corals, seaweeds and other marine organisms. We previously reviewed anti-inflammatory compounds, as well as crude extracts isolated from echinoderms such as sea cucumbers, sea urchins and starfish. In the present review, we evaluate the anti-inflammatory effects of compounds from other marine organisms, including macroalgae (seaweeds), marine angiosperms (seagrasses), medusozoa (jellyfish), bryozoans (moss animals), mollusks (shellfish) and peanut worms. We also present a review of the molecular mechanisms of the anti-inflammatory activity of these compounds. Our objective in this review is to provide an overview of the current state of research on anti-inflammatory compounds from marine sources and the prospects for their translation into novel anti-inflammatory drugs.

Vitronectin Destroyed Intestinal Epithelial Cell Differentiation through Activation of PDE4-Mediated Ferroptosis in Inflammatory Bowel Disease

Objective

Vitronectin (VTN) has been reported to trigger cell pyroptosis to aggravate inflammation in our previous study. However, the function of VTN in inflammatory bowel disease (IBD) remains to be addressed.

Methods

Real-time PCR and western blotting were performed to analyze VTN-regulated intestinal epithelial cell (IEC) differentiation through ferroptosis, and immunofluorescence (IF), luciferase, and chromatin immunoprecipitation were used to identify whether VTN-modulated ferroptosis is dependent on phosphodiesterase 4 (PDE4)/protein kinase A (PKA)/cyclic adenosine monophosphate-response element-binding protein (CREB) cascade pathway. In vivo experiment in mice and a pilot study in patients with IBD were used to confirm inhibition of PDE4-alleviated IECs ferroptosis, leading to cell differentiation during mucosal healing.

Results

Herein, we found that caudal-related homeobox transcription factor 2-mediated IECs differentiation was impaired in response to VTN, which was attributed to enhanced ferroptosis characterized by decreased glutathione peroxidase 4 (GPX4) and solute carrier family 7 member 11 expression. Inhibition of ferroptosis in IECs rescued the inhibitory effect of VTN on cell differentiation. Further analysis showed that VTN triggered phosphorylation of PDE4, leading to inhibit PKA/CREB activation and CREB nuclear translocation, which further reduced GPX4 transactivation. Endogenous PKA interacted with CREB, and this interaction was destroyed in response to VTN stimulation. What is more, overexpression of CREB in CaCO₂ cells overcame the promotion of VTN on ferroptosis. Most importantly, inhibition of PDE4 by roflumilast or dipyridamole could alleviate dextran sulfate sodium-induced colitis in mice and in a pilot clinical study confirmed by IF.

Conclusions

These findings demonstrated that highly expressed VTN disrupted IECs differentiation through PDE4-mediated ferroptosis in IBD, suggesting targeting PDE4 could be a promising therapeutic strategy for patients with IBD.

Antitumor Activity of Ferulic Acid Against Ehrlich Solid Carcinoma in Rats via Affecting Hypoxia, Oxidative Stress and Cell Proliferation

Background Ferulic acid is a natural compound commonly found in fruits and vegetables like tomatoes, sweet corn, rice bran, and dong quai. It has various beneficial effects on the body, such as anti-inflammatory, anti-apoptotic, hepatoprotective, cardioprotective, and neuroprotective properties. Aims We conducted a study to investigate the antitumor activity of ferulic acid against Ehrlich solid carcinoma (ESC), specifically by affecting hypoxia-inducible factor (HIF)-1α and its subsequent effects on other factors like nuclear factor erythroid 2-related factor 2 (Nrf2), heme oxygenase-1 (HO-1), cellular Myc (cMyc), cyclin D1, mammalian target of rapamycin (mTOR), and signal transducer and activator of transcription 3 (STAT3). Materials and methods The study involved implanting rats with ESC cells and administering 50 mg/kg of ferulic acid orally daily for eight days. Sections of the muscles with ESC were stained with toluidine blue or immunostained with anti-HIF-1α antibodies. The tumor samples were used to evaluate the expression of HIF-1α, Nrf2, HO-1, cMyc, cyclin D1, mTOR, and STAT3. Results Ferulic acid increased mean survival time, reduced tumor volume and weight, and improved the appearance of the tumor tissue. Furthermore, ferulic acid significantly elevated the expression of Nrf2 and HO-1, while reducing the expression of HIF-1α, Nrf2, HO-1, cMyc, cyclin D1, mTOR, and STAT3. Conclusions Ferulic acid can reduce tumor size and weight while improving the structure of muscle cells, suggesting it may have antineoplastic activity against ESC. Further investigation revealed that ferulic acid downregulates HIF-1α, increasing the expression of antioxidant proteins Nrf2 and HO-1. Additionally, ferulic acid decreases the expression of proliferation markers cMyc and cyclin D1 and downregulates cellular regulators mTOR and STAT3.

Antitumor Activity of Ligustilide Against Ehrlich Solid Carcinoma in Rats via Inhibition of Proliferation and Activation of Autophagy

Background Cancer is the second-leading cause of death worldwide. According to a 2018 WHO report, 9.6 million deaths occurred globally due to cancer. Ehrlich carcinoma is characterized by rapid proliferation and a short survival time. Ligustilide is a phthalide derivative and is one of the main compounds in Danggui essential oil and Rhizoma Chuanxiong. It has many protective effects, such as anticancer, anti-inflammatory, antioxidant, and neuroprotective effects. Aims We conducted this study to investigate the antitumor activity of ligustilide against Ehrlich solid carcinoma (ESC) in rats by affecting beclin 1, mammalian target of rapamycin (mTOR), B-cell lymphoma 2 (BCL2), and 5' AMP-activated protein kinase (AMPK). Materials and methods Twenty rats were intramuscularly implanted in the thigh of the left hind limb with a 200-µL tumor cell suspension in PBS containing 2 × 10⁶ cells. After eight days of inoculation, 10 rats out of the 20 were treated with oral 20 mg/kg ligustilide daily. At the end of the experiment, samples of muscles with ESC were separated. Sections prepared from the muscle samples with ESC were immunohistochemically stained with anti-Ki67 antibodies. Another part of the muscle samples with ESC was used to assess gene expression and protein levels of beclin 1, mTOR, BCL2, and AMPK. Results  Treatment of carcinoma rats with ligustilide elevated the mean survival time and reduced tumor volume and weight. Moreover, examination of tumor tissue stained with hematoxylin/eosin showed an infiltrative, highly cell-dense mass supported by a small to moderate amount of fibrovascular stroma and intersected with multifocal myofibril necrosis. Treatment with ligustilide ameliorated all these effects in the carcinoma group without affecting the control group. Finally, treatment with ligustilide significantly decreased the expression of beclin 1, mTOR, and AMPK associated with elevated expression of BCL2. Conclusions  Our study aimed to explore the potential chemotherapeutic activity of ligustilide against ESC. We found that ligustilide effectively reduced tumor size and weight, indicating its antineoplastic activity against ESC. We further investigated that ligustilide inhibits cell proliferation by suppressing Ki67 and mTOR and activates autophagy through beclin 1 activation. Moreover, ligustilide inhibits apoptosis by upregulating BCL2. Finally, ligustilide reduced the expression of AMPK, preventing its ability to promote tumor cell growth.

Curative effects of crocin in ulcerative colitis via modulating apoptosis and inflammation

Ulcerative colitis (UC) is an inflammatory bowel disease with characteristic inflammation to mucosal cells in rectum and colon leading to lesions in mucosa and submucosa. Moreover, crocin is a carotenoid compound among active constituents of saffron with many pharmacological effects as antioxidant, anti-inflammatory and anticancer activities. Therefore, we aimed to investigate therapeutic effects of crocin against UC through affecting the inflammatory and apoptotic pathways. For induction of UC in rats, intracolonic 2 ml of 4% acetic acid was used. After induction of UC, part of rats was treated with 20 mg/kg crocin. cAMP was measured using ELISA. Moreover, we measured gene and protein expression of B-cell lymphoma 2 (BCL2), BCL2-associated X (BAX), caspase-3/8/9, NF-κB, tumor necrosis factor (TNF)-α and IL-1β/4/6/10. Colon sections were stained with hematoxylin-eosin and Alcian blue or immune-stained with anti-TNF-α antibodies. Microscopic images of colon sections in UC group revealed destruction of intestinal glands associated with infiltration of inflammatory cell and severe hemorrhage. While images stained with Alcian blue showed damaged and almost absent intestinal glands. Crocin treatment ameliorated morphological changes. Finally, crocin significantly reduced expression levels of BAX, caspase-3/8/9, NF-κB, TNF-α, IL-1β and IL-6, associated with increased levels of cAMP and expression of BCL2, IL-4 and IL-10. In conclusion, protective of action of crocin in UC is proved by restoration of normal weight and length of colon as well as improvement of morphological structure of colon cells. The mechanism of action of crocin in UC is indicated by activation of anti-apoptotic and anti-inflammatory effects.

Effects of Medicinal Plants and Phytochemicals in Nrf2 Pathways during Inflammatory Bowel Diseases and Related Colorectal Cancer: A Comprehensive Review

Inflammatory bowel diseases (IBDs) are related to nuclear factor erythroid 2-related factor 2 (Nrf2) dysregulation. In vitro and in vivo studies using phytocompounds as modulators of the Nrf2 signaling in IBD have already been published. However, no existing review emphasizes the whole scenario for the potential of plants and phytocompounds as regulators of Nrf2 in IBD models and colitis-associated colorectal carcinogenesis. For these reasons, this study aimed to build a review that could fill this void. The PubMed, EMBASE, COCHRANE, and Google Scholar databases were searched. The literature review showed that medicinal plants and phytochemicals regulated the Nrf2 on IBD and IBD-associated colorectal cancer by amplifying the expression of the Nrf2-mediated phase II detoxifying enzymes and diminishing NF-κB-related inflammation. These effects improve the bowel environment, mucosal barrier, colon, and crypt disruption, reduce ulceration and microbial translocation, and consequently, reduce the disease activity index (DAI). Moreover, the modulation of Nrf2 can regulate various genes involved in cellular redox, protein degradation, DNA repair, xenobiotic metabolism, and apoptosis, contributing to the prevention of colorectal cancer.