A lecithinized superoxide dismutase (PC-SOD) improves ulcerative colitis

Hyaluronic Acid Receptor-Mediated Nanomedicines and Targeted Therapy

Hyaluronic acid (HA) is a naturally occurring polysaccharide found in the extracellular matrix with broad applications in disease treatment. HA possesses good biocompatibility, biodegradability, and the ability to interact with various cell surface receptors. Its wide range of molecular weights and modifiable chemical groups make it an effective drug carrier for drug delivery. Additionally, the overexpression of specific receptors for HA on cell surfaces in many disease states enhances the accumulation of drugs at pathological sites through receptor binding. In this review, the modification of HA with drugs, major receptor proteins, and the latest advances in receptor-targeted nano drug delivery systems (DDS) for the treatment of tumors and inflammatory diseases are summarized. Furthermore, the functions of HA with varying molecular weights of HA in vivo and the selection of drug delivery methods for different diseases are discussed.

Orally Deliverable Microalgal-Based Carrier with Selenium Nanozymes for Alleviation of Inflammatory Bowel Disease

Excessive reactive oxygen species (ROS) is a hallmark of both the onset and progression of inflammatory bowel disease (IBD), where a continuous cycle of ROS and inflammation drives the progression of diseases. The design of oral antioxidant nanoenzymes for scavenging ROS has emerged as a promising strategy to intervene in IBD. However, the practical application of these nanoenzymes is limited due to their single catalytical property and significantly impacted by substantial leakage in the upper gastrointestinal tract. This study introduces a novel oral delivery system, SP@CS-SeNPs, combining natural microalgae Spirulina platensis (SP), which possesses superoxide dismutase (SOD)-like activity, with chitosan-functionalized selenium nanoparticles (CS-SeNPs) that exhibit catalase-like activity. The SP@CS-SeNPs system leverages the dual catalytic capabilities of these components to initiate a cascade reaction that first converts superoxide anion radicals (O2•-) into hydrogen peroxide (H2O2), and then catalyzes the decomposition of H2O2 into water and oxygen. This system not only utilizes the resistance of the microalgae carrier to gastric acid and its efficient capture by intestinal villi, thereby enhancing intestinal distribution and retention but also demonstrates significant anti-inflammatory effects and effective repair of the damaged intestinal barrier in a colitis mice model. These results demonstrate that this oral delivery system successfully combines the features of microalgae and nanozymes, exhibits excellent biocompatibility, and offers a novel approach for antioxidant nanozyme intervention in IBD.

Hydrogel-forming viscous liquid in response to ROS restores the gut mucosal barrier of colitis mice via regulating oxidative redox homeostasis

The disrupted oxidative redox homeostasis plays a critical role in the progress of ulcerative colitis (UC). Herein, hydrogel-forming viscous liquid (HSD) composed of cysteamine-grafted hyaluronic acid (HS) and superoxide dismutase (SOD) has been designed for UC. When the viscous HSD liquid was infused into colitis colon, SOD would convert the pathological superoxide (O2·-) to hydrogen peroxides (H2O2), which was subsequently scavenged by HS. Accordingly, the sol-gel transition of HSD was initiated by scavenging H2O2, enhancing its adhesion toward colitis colon. H2O2-treated HSD presented the higher storage modulus and stronger adhesion force toward porcine colon than the untreated HSD. Besides, H2O2-treated HSD presented the slower erosion profile in the colitis-mimicking medium (pH 3-5), while its rapid degradation was displayed in physiologic condition (pH7.4). The combination of pH-resistant erosion and ROS-responsive adhesion for HSD rendered it with the specifical retention on the inflamed colonic mucosa of DSS-induced colitis mice. Rectally administrating HSD could effectively hinder the body weight loss, reduce the disease activity index and improve the colonic shorting of DSS-induced colitis mice. Moreover, the pro-inflammatory cytokines (IL-1β, IL-6 and TNF-α) were substantially decreased, the colonic epitheliums were well rearranged and the tight junction proteins were greatly recovered after HSD treatment. Besides, HSD also modulated the gut flora, markedly augmenting the abundance of Firmicutes, Barnesiella and Lachnospiraceae. Moreover, HSD treatment could regulate oxidative redox homeostasis via activating Nrf2-HO-1 pathway to reduce ROS and malondialdehyde and upregulate antioxidant enzymes (SOD, GPx and GSH). Collectively, HSD might be a promising therapy for UC treatments. STATEMENT OF SIGNIFICANCE: Herein, a hydrogel-forming viscous liquid (HSD) was designed by cysteamine-grafted hyaluronic acid (HS) and superoxide dismutase (SOD) for UC treatments. When the viscous HSD liquid was infused into a colitis colon, SOD would convert the pathological superoxide to hydrogen peroxides (H2O2), which was subsequently scavenged by HS. Accordingly, the sol-gel transition of HSD was initiated by scavenging H2O2, enhancing its adhesion to the colitis colon. The colonic epitheliums of DSS-induced colitis mice were well rearranged and the tight junction proteins (Zonula-1 and Claudin-5) were greatly recovered after the HSD treatment. Moreover, the HSD treatment could regulate oxidative redox homeostasis via activating the Nrf2-HO-1 pathway to reduce ROS and malondialdehyde and upregulate antioxidant enzymes (SOD, GPx and GSH).

Disengaging the COVID-19 Clutch as a Discerning Eye Over the Inflammatory Circuit During SARS-CoV-2 Infection

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes the cytokine release syndrome (CRS) and leads to multiorgan dysfunction. Mitochondrial dynamics are fundamental to protect against environmental insults, but they are highly susceptible to viral infections. Defective mitochondria are potential sources of reactive oxygen species (ROS). Infection with SARS-CoV-2 damages mitochondria, alters autophagy, reduces nitric oxide (NO), and increases both nicotinamide adenine dinucleotide phosphate oxidases (NOX) and ROS. Patients with coronavirus disease 2019 (COVID-19) exhibited activated toll-like receptors (TLRs) and the Nucleotide-binding and oligomerization domain (NOD-), leucine-rich repeat (LRR-), pyrin domain-containing protein 3 (NLRP3) inflammasome. The activation of TLRs and NLRP3 by SARS-CoV-2 induces interleukin 6 (IL-6), IL-1β, IL-18, and lactate dehydrogenase (LDH). Herein, we outline the inflammatory circuit of COVID-19 and what occurs behind the scene, the interplay of NOX/ROS and their role in hypoxia and thrombosis, and the important role of ROS scavengers to reduce COVID-19-related inflammation.

Superoxide dismutase: an updated review on its health benefits and industrial applications

Many short-lived and highly reactive oxygen species, such as superoxide anion (O₂^-) and hydrogen peroxide (H₂O₂), are toxic or can create oxidative stress in cells, a response involved in the pathogenesis of numerous diseases depending on their concentration, location, and cellular conditions. Superoxide dismutase (SOD) activities as an endogenous and exogenous cell defense mechanism include the potential use in treating various diseases, improving the potential use in treating various diseases, and improving food-stuffs preparation dietary supplements human nutrition. Published work indicates that SOD regulates oxidative stress, lipid metabolism, inflammation, and oxidation in cells. It can prevent lipid peroxidation, the oxidation of low-density lipoprotein in macrophages, lipid droplets' formation, and the adhesion of inflammatory cells into endothelial monolayers. It also expresses antioxidant effects in numerous cancer-related processes. Additionally, different forms of SOD may also augment food processing and pharmaceutical applications, exhibit anticancer, antioxidant, and anti-inflammatory effects, and prevent arterial problems by protecting the proliferation of vascular smooth muscle cells. Many investigations in this review have reported the therapeutic ability and physiological importance of SOD. Because of their antioxidative effects, SODs are of great potential in the medicinal, cosmetic, food, farming and chemical industries. This review discusses the findings of human and animal studies that support the advantages of SOD enzyme regulations to reduce the formation of oxidative stress in various ways.

Antioxidant Therapy in Inflammatory Bowel Diseases

Inflammatory bowel diseases (IBD) are a group of chronic, incurable diseases of the digestive tract, the etiology of which remains unclear to this day. IBD result in significant repercussions on the quality of patients’ life. There is a continuous increase in the incidence and prevalence of IBD worldwide, and it is becoming a significant public health burden. Pharmaceuticals commonly used in IBD management, for example, mesalamine, sulfasalazine, corticosteroids, and others, expose patients to diverse, potentially detrimental side effects and frequently do not provide sufficient disease control. The chronic inflammation underlies the etiology of IBD and closely associates with oxidative/nitrosative stress and a vast generation of reactive oxygen/nitrogen species. Relative to this, several substances with antioxidant and anti-inflammatory properties are now intensively researched as possible adjunctive or independent treatment options in IBD. Representatives of several different groups, including natural and chemical compounds will be characterized in this dissertation.

Preventing Colitis-Associated Colon Cancer With Antioxidants: A Systematic Review

Inflammatory bowel disease (IBD) patients have an increased risk of developing colitis-associated colon cancer (CAC); however, the basis for inflammation-induced genetic damage requisite for neoplasia is unclear. Several studies have shown that IBD patients have signs of increased oxidative damage, which could be a result of genetic and environmental factors such as an excess in oxidant molecules released during chronic inflammation, mitochondrial dysfunction, a failure in antioxidant capacity, or oxidant promoting diets. It has been suggested that chronic oxidative environment in the intestine leads to the DNA lesions that precipitate colon carcinogenesis in IBD patients. Indeed, several preclinical and clinical studies show that different endogenous and exogenous antioxidant molecules are effective at reducing oxidation in the intestine. However, most clinical studies have focused on the short-term effects of antioxidants in IBD patients but not in CAC. This review article examines the role of oxidative DNA damage as a possible precipitating event in CAC in the context of chronic intestinal inflammation and the potential role of exogenous antioxidants to prevent these cancers.

Arjunarishta alleviates experimental colitis via suppressing proinflammatory cytokine expression, modulating gut microbiota and enhancing antioxidant effect

Traditional ayurvedic medicine, Arjunarishta (AA) is used to treat several inflammatory conditions including dysentery associated with blood. The formulation is a decoction of Terminalia arjuna (Roxb.) Wight and Arn. (TA), Madhuca indica J.F.Gmel., Vitis vinifera L., Woodfordia fruticosa (L.) Kurz., and Saccharum officinarum L. Terminalia arjuna, a major constituent of this formulation has been recognized for anti-inflammatory effects. This study aimed at evaluating beneficial effects of AA and probable mechanism of action in Trinitrobenzenesulphonicacid (TNBS) induced colitis model. Response to AA treatment was explored through determination of disease activity index (DAI), histological assessment and damage scores, colonic pro-inflammatory cytokine/chemokine expression and estimation of oxidative stress biomarkers. Improvement in gut microbiome and plasma zinc level was also assessed. Study findings directed therapeutic effects of AA treatment in colitis model by attenuating the colitis symptoms such as weight loss, diarrhoea, blood in stool; histological damage; and downregulated expression of pro-inflammatory cytokines/chemokine (TNF-α, IL-1β, IL-6) and MCP-1). Similarly reduced oxidative stress by decreased level of Nitric Oxide (NO), Myeloperoxidase (MPO), Malondialdehyde (MDA) and enhanced level of Catalase (CAT), Superoxide dismutase (SOD) and Reduced Glutathione (GSH) was also witnessed. In addition, an improved beneficial fecal microbiome profile and restored plasma zinc status was revealed compared to the TNBS control group. The present study directs that downregulated pro-inflammatory cytokines/chemokine expression, enhancement of antioxidant effect, increased plasma zinc status and promising role in modulating fecal microbiome might be potential mechanisms for the therapeutic effect of AA treatment against colitis.

Characteristics of the Copper,Zinc Superoxide Dismutase of a Hadal Sea Cucumber (Paelopatides sp.) from the Mariana Trench

Superoxide dismutases (SODs) are among the most important antioxidant enzymes and show great potential in preventing adverse effects during therapeutic trials. In the present study, cloning, expression, and characterization of a novel Cu,Zn superoxide dismutase (Ps-Cu,Zn-SOD) from a hadal sea cucumber (Paelopatides sp.) were reported. Phylogenetic analysis showed that Ps-Cu,Zn-SOD belonged to a class of intracellular SOD. Its Km and Vmax were 0.0258 ± 0.0048 mM and 925.1816 ± 28.0430 units/mg, respectively. The low Km value of this enzyme represents a high substrate affinity and can adapt to the low metabolic rate of deep sea organisms. The enzyme functioned from 0 °C to 80 °C with an optimal temperature of 40 °C. Moreover, the enzyme activity was maintained up to 87.12% at 5 °C. The enzyme was active at pH 4 to 12 with an optimal pH of 8.5. Furthermore, Ps-Cu,Zn-SOD tolerated high concentration of urea and GuHCl, resisted hydrolysis by proteases, and maintained stability at high pressure. All these features demonstrated that the deep sea Ps-Cu,Zn-SOD is a potential candidate for application to the biopharmaceutical field.

Pathomechanisms of Oxidative Stress in Inflammatory Bowel Disease and Potential Antioxidant Therapies

Inflammatory bowel disease (IBD) is a chronic gastrointestinal disease whose incidence has risen worldwide in recent years. Accumulating evidence shows that oxidative stress plays an essential role in the pathogenesis and progression of IBD. This review highlights the generation of reactive oxygen species (ROS) and antioxidant defense mechanisms in the gastrointestinal (GI) tract, the involvement of oxidative stress signaling in the initiation and progression of IBD and its relationships with genetic susceptibility and the mucosal immune response. In addition, potential therapeutic strategies for IBD that target oxidative stress signaling are reviewed and discussed. Though substantial progress has been made in understanding the role of oxidative stress in IBD in humans and experimental animals, the underlying mechanisms are still not well defined. Thus, further studies are needed to validate how oxidative stress signaling is involved in and contributes to the development of IBD.

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.

Double-blind controlled trial of lecithinized superoxide dismutase in patients with idiopathic interstitial pneumonia - short term evaluation of safety and tolerability

BACKGROUND

Idiopathic interstitial pneumonias such as idiopathic pulmonary fibrosis or fibrotic nonspecific interstitial pneumonia are irreversible progressive pulmonary diseases that often have fatal outcomes. Although the etiology of idiopathic interstitial pneumonias is not yet fully understood, anti-fibrotic and anti-inflammatory agents have shown limited therapeutic effectiveness. Reactive oxygen species and their cytotoxic effects on the lung epithelial cells have been reported to participate in the pathophysiology of the disease. Because superoxide dismutase catalyzes the detoxification of reactive oxygen species, we developed lecithinized superoxide dismutase for the treatment of patients with idiopathic interstitial pneumonias.

METHODS

A multicenter, randomized, placebo-controlled trial was conducted as a pilot study to investigate the safety and effectiveness of 40 or 80 mg lecithinized superoxide dismutase in patients with progressive idiopathic interstitial pneumonias who presented with either idiopathic pulmonary fibrosis or corticosteroid-resistant fibrotic nonspecific interstitial pneumonia and showed arterial oxygen tension compatible with stage III or IV on the Japanese severity grading scale for idiopathic interstitial pneumonias. Before and following infusion of lecithinized superoxide dismutase for 28 days, the primary endpoint of forced vital capacity and the secondary endpoints of lactate dehydrogenase, surfactant protein-A, surfactant protein-D and Krebs von den Lungen-6 levels were measured in the serum.

RESULTS

The primary endpoint of forced vital capacity did not improve significantly in the lecithinized superoxide dismutase groups in comparison with the placebo group. The secondary endpoints of lactate dehydrogenase and surfactant protein-A levels were significantly attenuated by 28 days in the higher-dose (80 mg) group. However, these changes returned to the baseline levels by 56 days after the cessation of lecithinized superoxide dismutase. Adverse events and mortality in the drug-treated groups did not differ from those in the placebo group.

CONCLUSIONS

Treatment with lecithinized superoxide dismutase is safe and improves the levels of serum markers such as lactate dehydrogenase and surfactant protein-A in patients with advanced idiopathic interstitial pneumonias with severe respiratory dysfunction. Considering the results of the current study, further investigations into the effects and treatment potential of long-term administration of lecithinized superoxide dismutase may be warranted.

TRIAL REGISTRATION

University hospital Medical Information Network (UMIN) clinical trials registry no. 000000752.

High beta-palmitate fat controls the intestinal inflammatory response and limits intestinal damage in mucin Muc2 deficient mice

BACKGROUND

Palmitic-acid esterified to the sn-1,3 positions of the glycerol backbone (alpha, alpha'-palmitate), the predominant palmitate conformation in regular infant formula fat, is poorly absorbed and might cause abdominal discomfort. In contrast, palmitic-acid esterified to the sn-2 position (beta-palmitate), the main palmitate conformation in human milk fat, is well absorbed. The aim of the present study was to examine the influence of high alpha, alpha'-palmitate fat (HAPF) diet and high beta-palmitate fat (HBPF) diet on colitis development in Muc2 deficient (Muc2(-/-)) mice, a well-described animal model for spontaneous enterocolitis due to the lack of a protective mucus layer.

METHODS

Muc2(-/-) mice received AIN-93G reference diet, HAPF diet or HBPF diet for 5 weeks after weaning. Clinical symptoms, intestinal morphology and inflammation in the distal colon were analyzed.

RESULTS

Both HBPF diet and AIN-93G diet limited the extent of intestinal erosions and morphological damage in Muc2(-/-) mice compared with HAPF diet. In addition, the immunosuppressive regulatory T (Treg) cell response as demonstrated by the up-regulation of Foxp3, Tgfb1 and Ebi3 gene expression levels was enhanced by HBPF diet compared with AIN-93G and HAPF diets. HBPF diet also increased the gene expression of Pparg and enzymatic antioxidants (Sod1, Sod3 and Gpx1), genes all reported to be involved in promoting an immunosuppressive Treg cell response and to protect against colitis.

CONCLUSIONS

This study shows for the first time that HBPF diet limits the intestinal mucosal damage and controls the inflammatory response in Muc2(-/-) mice by inducing an immunosuppressive Treg cell response.

Different profile of peripheral antioxidant enzymes and lipid peroxidation in active and non-active inflammatory bowel disease patients

BACKGROUND

The role of oxidative stress in inflammatory bowel diseases (IBD) has been extended lately from a simple consequence of inflammation to a potential etiological factor, but the data are still controversial. Active disease has been characterized before by an enhanced production of reactive oxygen species and the increased peroxidation of lipids, but patients in remission were generally not considered different from healthy people in terms of oxidative stress.

AIMS

We evaluated the antioxidant defense capacity and lipid peroxidation status in the serum of patients with active and non-active disease compared with healthy matched control subjects.

METHODS

The study included 20 patients with confirmed IBD in clinical and biological remission, 21 patients with active disease, and 18 controls. We determined the serum levels of two antioxidant enzymes, superoxide dismutase (SOD) and glutathione peroxidase (GPX), and a lipid peroxidation marker, malondialdehyde (MDA).

RESULTS

Active disease patients had an increased activity of both SOD and GPX, as well as significant high values of MDA versus controls. Furthermore, patients being in remission had significantly lower values of antioxidant enzymes (SOD and GPX) and increased lipid peroxidation measured by MDA serum levels, as compared with healthy control subjects.

CONCLUSIONS

Our study confirmed the presence of high oxidative stress in active IBD. More importantly, we have demonstrated a lower antioxidant capacity of patients in remission versus control group. This may represent a risk factor for the disease and can be an additional argument for the direct implication of oxidative stress in the pathogenesis of IBD.

A Picrorhiza kurroa derivative, picroliv, attenuates the development of dextran-sulfate-sodium-induced colitis in mice

Background. Free radicals and proinflammatory cytokines have been shown to play a critical role in the pathogenesis of ulcerative colitis (UC). Picroliv, a Picrorhiza kurroa derivative, has been demonstrated to have antioxidant and anti-inflammatory effect. The purpose of the study was to investigate the effects of picroliv on experimental model of UC in mice. Materials and Methods. Picroliv was administrated orally by gavage to mice with colitis induced by dextran sulfate sodium (DSS). Disease activity index (DAI), colon length, and histology score were observed. Myeloperoxidase (MPO) activity, and SOD, MDA concentrations were measured by enzyme-linked immunosorbent assay (ELISA) while the expression of cytokine mRNAs was studied by real-time-quantitative polymerase chain reaction and also ELISA. The expression of NF-κB p65 was observed by immunohistochemistry staining and western blotting. Results. A significant improvement was observed in DAI and histological score in mice treated with picroliv, and incerased MPO activity, MDA concentrations, and the expression of IL-1β, TNF-α, and NF-κB p65 in mice with DSS-induced colitis were significantly reduced while decreased SOD level increased following administration of picroliv. Conclusion. The administration of picroliv leads to an amelioration of DSS-induced colitis, suggesting administration of picroliv may provide a therapeutic approach for UC.

Keratinocyte growth factor gene therapy ameliorates ulcerative colitis in rats

AIM: To investigate the effect of keratinocyte growth factor (KGF) gene therapy in acetic acid-induced ulcerative colitis in rat model.

METHODS: The colitis of Sprague-Dawley rats was induced by intrarectal infusion of 1 mL 5% (v/v) acetic acid. Twenty-four hours after exposed to acetic acid, rats were divided into three experimental groups: control group, attenuated Salmonella typhimurium Ty21a strain (SP) group and SP strain carrying human KGF gene (SPK) group, and they were separately administered orally with 10% NaHCO₃, SP or SPK. Animals were sacrificed and colonic tissues were harvested respectively on day 3, 5, 7 and 10 after administration. Weights of rats, colonic weight/length ratio and stool score were evaluated. Histological changes of colonic tissues were examined by hematoxylin and eosin (HE) staining method. The expression of KGF, KGF receptor (KGFR) and TNF-α were measured either by enzyme-linked immunosorbent assay or Western blotting. Immunohistochemistry was used to detect the cellular localization of KGFR and Ki67. In addition, superoxide dismutase (SOD) activity and malondialdehyde (MDA) contents in the homogenate were measured.

RESULTS: Body weight and colonic weight/length ratio were declined in SPK group compared with SP and control groups (body weight: 272.78 ± 17.92 g vs 243.72 ± 14.02 g and 240.68 ± 12.63 g, P < 0.01; colonic weight/length ratio: 115.76 ± 7.47 vs 150.32 ± 5.99 and 153.67 ± 5.50 mg/cm, P < 0.01). Moreover, pathological changes of damaged colon were improved in SPK group as well. After administration of SPK strain, KGF expression increased markedly from the 3rd d, and remained at a high level till the 10th d. Furthermore, KGFR expression and Ki67 expression elevated, whereas TNF-α expression was inhibited in SPK group. In the group administered with SPK, SOD activity increased significantly (d 5: 26.18 ± 5.84 vs 18.12 ± 3.30 and 18.79 ± 4.74 U/mg, P < 0.01; d 7: 35.48 ± 3.35 vs 22.57 ± 3.44 and 21.69 ± 3.94 U/mg, P < 0.01; d 10: 46.10 ± 6.23 vs 25.35 ± 4.76 and 27.82 ± 6.42 U/mg, P < 0.01) and MDA contents decreased accordingly (d 7: 7.40 ± 0.88 vs 9.81 ± 1.21 and 10.45 ± 1.40 nmol/mg, P < 0.01; d 10: 4.36 ± 0.62 vs 8.41 ± 0.92 and 8.71 ± 1.27 nmol/mg, P < 0.01), compared with SP and control groups.

CONCLUSION: KGF gene therapy mediated by attenuated Salmonella ameliorates ulcerative colitis induced by acetic acids, and it may be a safe and effective treatment for ulcerative colitis.

Biopharmacology of enzyme conjugates: vasoprotective activity of supramolecular superoxide dismutase-chondroitin sulfate-catalase derivative

Bienzyme conjugate was obtained by the covalent connection of superoxide dismutase with catalase through endothelial glycocalyx glycosaminoglycan - chondroitin sulfate (SOD-CHS-CAT). This SOD-CHS-CAT conjugate has vasoprotective activity in respect to platelet interactions, tonus of the ring arterial fragment of a rat blood vessel, as well as normalization of hemodynamic parameters in rats and rabbits in conditions of oxidative stress caused by the administration of hydrogen peroxide. The SOD-CHS-CAT conjugate had antiplatelet potential due to its antiaggregation action manifested through the combination of enzyme activities and an acquired supramolecular structure. The influence on arterial fragment tonus was equivalent for SOD and CAT in native and conjugated form. Blood pressure and heart rate were significant and effectively normalized with SOD-CHS-CAT conjugate in rats and rabbits (after hydrogen peroxide administration as a perturbance stimulus). We have discovered the possibility of using the antioxidant bienzyme conjugate in chronic prophylaxis. It is important for a real development of the oral form of the SOD-CHS-CAT conjugate. These results indicate that the development of enzyme conjugates can be medically significant, as a promising approach for the creation of new drugs.

Balsalazine decreases intestinal mucosal permeability of dextran sulfate sodium-induced colitis in mice

AIM

To investigate the effect of balsalazine treatment on intestinal mucosal permeability in dextran sulfate sodium (DSS)-induced colitis and to determine the mechanism of the balsalazine-induced changes.

METHODS

Experimental colitis was induced in C57BL/6J mice by the administration of 5% DSS. Balsalazine was administered intragastrically at doses of 42, 141, and 423 mg/kg. The disease activity index (DAI) score was evaluated and colon tissue was collected for the assessment of histological changes. The amount of malondialdehyde (MDA) in the colon was determined, along with the activity of myeloperoxidase (MPO), superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px). Mucosa from the small intestine was collected to determine the levels of tumor necrosis factor (TNF)-alpha and interferon (IFN)-gamma. The mucosa was ultrastructurally examined with transmission electron microscopy and intestinal permeability was assayed using Evans blue.

RESULTS

Balsalazine was found to reduce the DAI score and the histological index (HI) score, decrease the MDA content and the activity of MPO, and increase the activity of SOD and GSH-Px in colitis mice. At the same time, balsalazine ameliorated microvillus and tight junction structure, resulting in a decrease in the amount of Evans blue permeating into the intestinal wall and the levels of TNF-alpha and IFN-gamma in colitis mice.

CONCLUSION

In colitis mice, the anti-colitis effect of balsalazine results in a decrease in intestinal mucosal permeability. The mechanism of this effect is partly associated with balsalazine's antioxidative and anti-inflammatory effects.Acta Pharmacologica Sinica (2009) 30: 987-993; doi: 10.1038/aps.2009.77.

The preventive effects of heparin-superoxide dismutase on carbon tetrachloride-induced acute liver failure and hepatic fibrosis in mice

In this study, the effects of heparin-superoxide dismutase conjugate (heparin-SOD) on carbon tetrachloride (CCl4)-induced acute liver failure and hepatic fibrosis were evaluated. To investigate the effects of heparin-SOD on acute liver failure, heparin-SOD was administered to CCl4-treated mice by intravenous injection. Biochemical indicators, such as glutamic oxaloacetic transaminase/glutamic pyruvic transaminase (GOT/GPT), GSH (glutathione), lactate dehydrogenase (LDH), and malondialdehyde (MDA) were determined 24 h after CCl4 treatment. The development of CCl4-induced acute liver failure altered the redox state with a decreased hepatic GSH and increased formation of lipid peroxidative products, which were partially normalized by treatment with heparin-SOD or heparin + SOD. Compared with other groups, the acute liver injury of heparin-SOD group was significantly lessened (reduced activities of GOT/GPT, MDA, and increased activities of GSH). To investigate the effects of heparin-SOD on hepatic fibrosis, heparin-SOD and CCl4 were co-administered by intraperitoneal injection twice a week for 12 weeks. Histological and hepatic hydroxyproline examination revealed that heparin-SOD could significantly prevent the progression of hepatic fibrosis. Moreover, real-time PCR was used to determine transforming growth factor-beta1 (TGF-beta1), metalloproteinase-2 (MMP-2), fibronectin, and collagen-I expression. Significantly, greater fibrosis and TGF-beta1, MMP-2, fibronectin, and collagen-I expression were found in the liver of CCl4-induced mice at the end of 12th week. Heparin-SOD could markedly attenuate the mRNA expression of TGF-beta1, MMP-2, and collagen-I. Western blots of tissue homogenates revealed that the protein expression of TGF-beta1 was substantially reduce also by heparin-SOD treatment. These results demonstrate that administration of heparin-SOD may be useful in the treatment and prevention of acute liver failure and hepatic fibrosis.