Induction of omega 6 inflammatory pathway by sodium metabisulfite in rat liver and its attenuation by ghrelin

Role of the Ghrelin System in Colitis and Hepatitis as Risk Factors for Inflammatory-Related Cancers

It is not known exactly what leads to the development of colorectal cancer (CRC) and hepatocellular carcinoma (HCC), but there are specific risk factors that increase the probability of their occurrence. The unclear pathogenesis, too-late diagnosis, poor prognosis as a result of high recurrence and metastasis rates, and repeatedly ineffective therapy of both cancers continue to challenge both basic science and practical medicine. The ghrelin system, which is comprised of ghrelin and alternative peptides (e.g., obestatin), growth hormone secretagogue receptors (GHS-Rs), and ghrelin-O-acyl-transferase (GOAT), plays an important role in the physiology and pathology of the gastrointestinal (GI) tract. It promotes various physiological effects, including energy metabolism and amelioration of inflammation. The ghrelin system plays a role in the pathogenesis of inflammatory bowel diseases (IBDs), which are well known risk factors for the development of CRC, as well as inflammatory liver diseases which can trigger the development of HCC. Colitis-associated cancer serves as a prototype of inflammation-associated cancers. Little is known about the role of the ghrelin system in the mechanisms of transformation of chronic inflammation to low- and high-grade dysplasia, and, finally, to CRC. HCC is also associated with chronic inflammation and fibrosis arising from different etiologies, including alcoholic and nonalcoholic fatty liver diseases (NAFLD), and/or hepatitis B (HBV) and hepatitis C virus (HCV) infections. However, the exact role of ghrelin in the progression of the chronic inflammatory lesions into HCC is still unknown. The aim of this review is to summarize findings on the role of the ghrelin system in inflammatory bowel and liver diseases in order to better understand the impact of this system on the development of inflammatory-related cancers, namely CRC and HCC.

Ghrelin Inhibits Intestinal Epithelial Cell Apoptosis Through the Unfolded Protein Response Pathway in Ulcerative Colitis

Ulcerative colitis (UC) is a type of inflammatory bowel disease (IBD) that occurs in the lining of the rectum and colon. Apoptosis of the intestinal epithelial cells (IECs) is common in active UC patients. Ghrelin is reported to be downregulated in apoptosis of IECs induced by tumor necrosis factor-α (TNF-α). Therefore, we hypothesized that ghrelin might play an antiapoptotic role in UC progression, which was investigated using in vitro and in vivo studies. The TNF-α-treated Caco-2 cell model and mouse colitis model induced by dextran sulfate sodium (DSS) or 2,4,6-trinitrobenzenesulfonic acid (TNBS) were established and employed. We found that ghrelin could inhibit the apoptosis of Caco-2 cells induced by TNF-α, which could be disturbed by [D-lys3]-GHRP-6, the antagonist of ghrelin receptor GHS-R1a. Similarly, in the DSS- and TNBS-induced mouse colitis models, ghrelin could also protect intestinal tissues from apoptosis in DSS- and TNBS-induced colitis depending on GHS-R1a. Furthermore, ghrelin modulated the unfolded protein response (UPR) pathway and regulated the expressions of caspase-3, BAX, and Bcl-2, which contributed to the inhibition of cell apoptosis. In conclusion, ghrelin protects IECs from apoptosis during the pathogenesis of colitis by regulating the UPR pathway.

An evaluation of subcutaneous apomorphine for the treatment of Parkinson's disease

INTRODUCTION

Heterogeneity of symptoms and individual variability of progression characterizes Parkinson's disease. Unmet therapeutic needs include a cure, disease modification, and improvement of available marketed dopamine-substituting compounds. Personalized treatment, tailored to the patients' needs and symptoms, aims to ameliorate impaired motor behavior and non-motor features. Injection or infusion of apomorphine is a therapeutic option for more advanced patients with severe levodopa associated motor complications.

AREAS COVERED

This narrative review summarizes the subcutaneous administration, efficacy, and side effects of the non-ergot derivative dopamine agonist apomorphine following a non-systematic literature research.

EXPERT OPINION

Subcutaneous apomorphine hydrochloride application rapidly terminates intervals with severe motor impairment with bolus injections. Oscillation of motor behavior well responds to continuous apomorphine infusions. Long-term application of the commercially available apomorphine hydrochloride solution sooner or later affects skin and oral mucosa. Onset of skin nodules associated with subcutaneous tissue inflammation probably results from the antioxidant preservative sodium metabisulfite in the apomorphine solution. Addition of another better tolerated and safer antioxidant instead of sodium metabisulphite or use of an already available concentrated apomorphine-free base formulation will enhance its future use, its tolerability, safety, and acceptance of subcutaneous and sublingual application.

Effect of Sodium Metabisulfite on Oxidative Stress and Lipid Peroxidation Biomarkers

Background:

Sulfites are widely used as preservatives in the foods and pharmaceutical agents. It has been demonstrated that sulfites can react with a variety of cellular components and cause toxicity.

Objective:

The present study was designed to investigate the effects of ingested sodium metabisulfite (SMB) on serum antioxidant status in rats.

Methods:

Thirty-two male Wistar rats were randomly divided into control and treated groups. Treated groups received 10, 100, and 260 mg/kg body weight of SMB for 28 days. After 28 days, serum was assayed for measuring superoxide dismtase (SOD), glutathione peroxidase (GPx), glutathione reductase (GR), catalase (CAT) activities, glutathion (GSH) level and lipid peroxidation.

Results:

The results showed that the activities of GPx, GR, CAT and GSH levels were significantly decreased in 100 and 260 mg/kg SMB treated rats, while malondialdehyde (MDA) level was significantly increased in 260 mg/kg treated group when compared with the control group.

Conclusion:

It is concluded that SMB administration as dose-dependent is associated with decreased serum antioxidant enzyme activities and increased lipid peroxidation.

Protective effect of vitamin E and vitamin C alone and in combination on testicular damage induced by sodium metabisulphite in rats: A stereological study

The existing investigation was directed to consider the protective role of vitamin C and E alone and in combination on sodium metabisulphite-induced damage on testicular. Experimental animals were received sodium metabisulphite (520 mg/kg) alone and in combination with vitamin E (100 mg/kg), vitamin C (100 mg/kg) and vitamin E + C, while the control groups received 0.9% saline solution and olive oil (the solvent of the vitamin E). Finally, the changes in the testis histology were examined stereologically. Lipid peroxidation was assessed through the measurement of malondialdehyde (MDA) levels in testis tissues. Also, serum testosterone concentrations were measured. The results indicated that 80%-90% (spermatogonia A and B, spermatocyte and Leydig) and 40% of the Sertoli cells were missed in the rats that received sodium metabisulphite, respectively, compared with the controls. The co-supplementation of vitamin E with vitamin C significantly decreased MDA (p = 0.006) and increased testosterone (p = 0.001) concentrations in the rats received SMB which were as much as control and olive groups. Co-supplementation of vitamin E and vitamin C due to their synergistic effects could be an appropriate strategy in preventing testicular from sodium metabisulphite-induced damage.

Attenuation of Sulfite-Induced Testicular Injury in Rats by Zingiber officinale Roscoe

Sulfite salts, including sodium metabisulfte, are widely used as preservatives in foods and pharmaceutical agents. Previous studies suggest that oxidative stress may be an important mediator of testicular injury. The present study was designed to elucidate the effect of exposure to sodium metabisulfite by gavage without or with Zingiber officinale (ginger) extract on the rat testes. Thirty-two male Wistar rats were randomly divided into control, ginger-treated (500 mg/kg/day), sodium metabisulfite- (SMB-) treated (260 mg/kg/day), and SMB + ginger- (SZ-) treated groups. After 28 days, the rats were anesthetized by ether and, after laparotomy, blood was collected from the heart to determine testosterone level by the enzyme-linked immunosorbent assay (ELISA) kit. Then left testes and cauda epididymis of all animals were removed for histological examination and sperm analysis, and right testes were removed for assessing lipid peroxidation (indexed by malondialdehyde [MDA]) and antioxidant enzymes. The results showed that spermatogenesis, epididymal morphometry, and sperm parameters were affected by SMB. There was a significant increase in MDA level and a significant reduction in the activities of glutathione peroxidase (GPx), glutathione reductase (GR), and catalase (CAT) in the SMB-treated rats compared to the control. Ginger treatment of SMB-exposed rats significantly increased testosterone level and the number of different spermatogenic cells. The level of MDA reversed to the control levels and the activities of GPx and GR were significantly increased when SMB was coadministered with ginger extract. It is concluded that coadministration of ginger, through its antioxidant and androgenic properties, exerts a protective effect against SMB-induced testicular oxidative stress.

Using curcumin to prevent structural impairments of testicles in rats induced by sodium metabisulfite

Sodium metabisulfite (Na-MBS) is a disinfectant and preservative agent. Some organ including testicle would be in danger in the case of Na-MBS consumption. Curcumin (CUR) is the constituent of turmeric with protective properties. The effect of CUR on testicles in rats exposed to Na-MBS evaluated using stereological methods. Sprague-Dawley rats were divided into eight groups. The rats in groups I to VIII received the following respectively: distilled water, CUR (100 mg/kg/day), low (0.7 mg/kg/day: acceptable daily intake), intermediate (7 mg/ kg/day), and high (70 mg/kg/day) doses of Na-MBS, and low, intermediate, and high doses of Na-MBS plus CUR. After 7 weeks, the testicles were analyzed. The volume of seminiferous tubule, tubular epithelium and tubule length reduced (25-40 %) on average in the rats that received intermediate and high doses of Na-MBS, while the connective tissue volume increased (15-20 %) in both groups (P<0.01). Besides, 19-36 % and 41-57 % of the cells (spermatogonia types A and B, spermatids, Sertoli and Leydig) were lost in the rats that received intermediate and high doses of Na-MBS respectively in comparison to the control groups. Nonetheless, all the above-mentioned alterations ameliorated drastically in the rats that received Na-MBS plus CUR compared to those exposed to Na-MBS without CUR therapy (P<0.01). The acceptable daily intake of Na-MBS for 7 weeks did not affect on testicular parameters. CUR (100 mg/kg/day) could prevent structural impairments of testicles in the rats induced by Na-MBS (7 and 70 mg/kg/day).