The role of α7nAChR in controlling the anti-inflammatory/anti-arthritic action of galantamine.

OBJECTIVE: The evolution of the "cholinergic anti-inflammatory pathway" and the fact that the α 7 subunit of the nicotinic acetylcholine receptor (α7nAChR) is present in the spleen, joint and on the surface of lymphocytes, opened up the prospective in this study of targeting the α7nAChR by the anticholinesterase and cholinergic drug, galantamine, to control inflammation in rheumatoid arthritis (RA). METHODS: Twelve-adjuvant arthritic rats were exposed to the selective α7nAChR blocker methylcaconitine citrate 15 min before galantamine treatment. As control, six adjuvant arthritic rats were treated with galantamine and six others were untreated. After five days TNF-α levels were assessed in spleen and joints, while reduced glutathione was measured in blood and joint tissue. In the second part, magnetically sorted CD4 + T cells from peripheral blood mononuclear cells of RA patients and healthy donors were used to sort CD4 + CD25 - primary T cells (Tresp) and CD4 + CD25 + CD127low Tregs. The suppressive function of Tregs was investigated after incubation with galantamine using flow cytometry. Cell culture supernatants were analyzed for TNF-α and IL-10 levels after three days incubation period of Tregs with Tresp. The effect of galantamine on Tregs was then blocked by α-Bungarotoxin and the same assay has been repeated. RESULTS & CONCLUSION: Selective α7nAChR blockade interrupted the anti-inflammatory effect of galantamine in the spleen and joints of arthritic rats. In healthy donors, galantamine could strengthen the suppressive activity of Tregs; while in RA patients it did not modulate the function of Tregs significantly. Further studies are necessary to investigate whether modulation of the cholinergic nervous system, especially α7nAChR, could have impact on the disturbed immune system in RA, which may open up a new treatment option of autoimmune diseases.

Evaluating the therapeutic potential of one-carbon donors in nonalcoholic fatty liver disease.

Defect in one-carbon metabolism is one of the multiple underlying pathological pathways contributing to NAFLD pathogenesis. Hence, our study was designed to examine whether different one-carbon donors; betaine, choline, and folic acid would possess beneficial effects in NAFLD treatment. Rats were fed with high fat diet and NAFLD rats were orally treated with different doses of betaine or choline or folic acid for 28 days. All used one-carbon donors had dose-dependent ameliorating effects on NAFLD as they succeeded to reduce body and relative liver weights, serum lipids and liver enzymes. These were accompanied by decreasing hepatic fat accumulation and amending hepatic histological structure. They also improved serum and hepatic redox systems (total glutathione (tGSH), reduced GSH, oxidized GSSG, and GSH/GSSG ratio), hepatic S-adenosylmethionine/S-adenosyl homocysteine (SAM/SAH) ratio and increased hepatic global DNA methylation. There were some discrepancies in the dose and the extent of their effect, where folic acid showed the most prominent effects that could be mediated through the significant surge in hepatic SAM/SAH ratio and better efficient correction of one-carbon metabolism than the other donors. Thus, one-carbon donors can be strongly considered in NAFLD management and might influence the whole therapeutic approaches of fatty liver diseases.

Post-irradiation protective effects of ectoine on brain and testicles in male mice.

BACKGROUND: The present study aimed to investigate the possible post-irradiation protective effects of ectoine on CNS and testes of male mice. METHODS: The study included thirty male Swiss albino mice (20-22 gm). Mice were divided into five groups (six each); controls (injected intraperitoneally with 0.2ml saline), irradiated group 1 (received six Gy whole body x-irradiation single dose, injected with saline, and sacrificed after one day), irradiated group 2 (x-irradiated, injected with saline, and sacrificed after one week), ectoine group 1 (x-irradiated, injected with 200mg/kg ectoine, and sacrificed after one day), and ectoine group 2 (x-irradiated, injected daily with 200mg/kg ectoine, and sacrificed after one week). IL-1ß, IL-6, IL-10, PGE2, MDA, GSH, GSSG, and GSH/GSSG ratio were evaluated in CNS and testes. RESULTS: IL-1ß, IL-6, IL-10, PGE2, and MDA are significantly elevated in the CNS and testes of x-irradiated groups when compared with controls. IL-1ß, IL-6, IL-10, and PGE2 significantly elevated at one week than one day while MDA significantly decreased. A significant decrease in the concentration of GSH and in the GSH/GSSG ratios coupled with an opposite effect on GSSG was noted. Ectoine treatment significantly ameliorated the biochemical effects induced by whole body x-irradiation. All the tested parameters tended to go back to near control values. It was noted that the modulating action was dependent on the accumulation of ectoine as it was more effective after repeated administration. CONCLUSION: Ectoine has post-irradiation protective effects on CNS and testes via its action on inflammatory and oxidative stress pathways.

Combination of Vildagliptin and Pioglitazone in Experimental Type 2 Diabetes in Male Rats.

Preclinical Research The majority of studies on vildagliptin and pioglitazone have focused on their combination in glycemic control. The aim of the present study was to investigate their effects in combination on (i) hyperglycemia-induced oxidative stress and inflammation and (ii) on organs involved in the pathophysiology of diabetes, pancreas, kidney and liver. Type 2 diabetes was induced using low-dose streptozotocin in male Wistar rats. Diabetic rats were treated for 4 weeks, with vildagliptin (10 mg/kg/day), pioglitazone (10 mg/kg/day) and their combination. Diabetic rats showed elevated fasting serum glucose, fasting serum insulin, serum transaminases together with a deleterious lipid profile and elevated serum creatinine and urea concentrations. Serum levels of the inflammatory markers tumor necrosis factor-α (TNF-α) and nitrite/nitrate were also elevated compared to normal rats. Oxidative stress was manifested by lowered hepatic reduced glutathione (GSH) and increased malondialdehyde (MDA) levels. Pancreatic sections from diabetic rats showed degenerated islets with poorly maintained architecture that was prevented by drug treatment. Pioglitazone was generally more effective than vildagliptin in the studied parameters except for the lipid profile where the effect of both drugs was comparable and for the liver enzymes and renal parameters where vildagliptin was more effective. The combination of vildagliptin and pioglitazone produced superior effects than either drug alone. Drug Dev Res 77 : 251-257, 2016. © 2016 Wiley Periodicals, Inc.

Effect of galantamine on adjuvant-induced arthritis in rats.

Stimulation of the vagus nerve suppresses cytokine production and macrophage activation, via the interaction of its neurotransmitter acetylcholine (ACh) with the α7 subunit of the nicotinic acetylcholine receptor (α7nAChR), present on neurons and inflammatory cells. The present study aimed to verify the potential anti-inflammatory effect of galantamine against experimental arthritis induced in rats. Fourteen days post adjuvant injection, Sprague-Dawley rats were treated orally with three doses of galantamine (1.25, 2.5 and 5 mg/kg) or leflunomide (10 mg/kg) for 2 weeks and arthritis progression was assessed by hind paw swelling. Additionally, serum biomarkers, viz., anti-cyclic citrullinated peptide antibodies (Anti-CCP), tumor necrosis factor-α (TNF-α), interleukin-10 (IL-10) and monocyte chemoattractant protein-1 (MCP-1) were measured. Radiological examination of the hind paws was also carried out to evaluate the degree of joint damage. Adjuvant arthritis led to a significant weight loss, marked swelling of the hind paw and alteration in the serum levels of anti-CCP, TNF-α, IL-10 and MCP-1. These alterations were associated with significant radiological changes of the joints. Galantamine, in a dose-dependent manner, reduced significantly all biomarkers of inflammation, with the highest dose showing the best beneficial anti-inflammatory effect that was superior in magnitude to the reference drug leflunomide in most of the studied parameters. In conclusion, these results suggest that galantamine may represent a novel, inexpensive and effective therapeutic strategy in the treatment of rheumatoid arthritis.

The combined effect of metformin and L-cysteine on inflammation, oxidative stress and insulin resistance in streptozotocin-induced type 2 diabetes in rats.

Increasing evidence has established causative links between obesity, chronic inflammation and insulin resistance; the core pathophysiological feature in type 2 diabetes mellitus. This study was designed to examine whether the combination of L-cysteine and metformin would provide additional benefits in reducing oxidative stress, inflammation and insulin resistance in streptozotocin-induced type 2 diabetes in rats. Male Wistar rats were fed a high-fat diet (HFD) for 8 weeks to induce insulin resistance after which they were rendered diabetic with low-dose streptozotocin. Diabetic rats were treated with metformin (300 mg/kg/day), L-cysteine (300 mg/kg/day) and their combination along with HFD for another 2 weeks. Control rats were fed normal rat chow throughout the experiment. At the end of treatment, fasting blood glucose, fasting serum insulin, homeostasis model assessment-insulin resistance index (HOMA-IR) and serum free fatty acids (FFAs) were measured. Serum levels of the inflammatory markers; monocyte chemoattractant protein-1 (MCP-1), C-reactive protein (CRP) and nitrite/nitrate were also determined. The liver was isolated and used for determination of malondialdehyde (MDA), reduced glutathione (GSH), caspase-3 and cytochrome c levels. The hypoglycemic effect of the combination therapy exceeded that of metformin and L-cysteine monotherapies with more improvement in insulin resistance. All treated groups exhibited significant reductions in serum FFAs, oxidative stress and inflammatory parameters, caspase-3 and cytochrome c levels compared to untreated diabetic rats with the highest improvement observed in the combination group. In conclusion, the present results clearly suggest that L-cysteine can be strongly considered as an adjunct to metformin in management of type 2 diabetes.

Evaluation of the effect of losartan and methotrexate combined therapy in adjuvant-induced arthritis in rats.

There is increasing body of evidence documenting the involvement of angiotensin II in inflammatory diseases. Moreover the up-regulation of angiotensin II AT(1) receptors in the synovium of rheumatoid arthritis patients has been previously described. This study aimed at investigating the anti-inflammatory effect of losartan, the selective angiotensin II AT(1) receptor blocker, and comparing the efficacy of methotrexate alone and in combination with losartan in adjuvant arthritis in rats. Twelve days post adjuvant injection, Sprague-Dawley rats were treated with methotrexate (1mg/kg/week), losartan (20mg/kg/day) and their combination for 15 days. Severity of arthritis was assessed by hind paw swelling, arthrogram scores. Serum was analyzed for measurement of albumin, C-reactive protein (CRP), nitrite/nitrate concentrations, interleukin 1ß (IL-1ß), tumor necrosis factor-α (TNF-α), vascular endothelial growth factor (VEGF), aspartate transaminase (AST) and alanine transaminase (ALT). Histopathological examination was done for hind paws and livers. Methotrexate and losartan monotherapies significantly reduced all parameters of inflammation and arthritis with better results in the methotrexate group except for the transaminases where losartan caused more significant reduction in their serum levels. The combined therapy showed better results than methotrexate and losartan alone. Hind paws showed better improvement of inflammatory cell infiltration and bone resorption in the combined therapy group. Disturbances in liver architecture and fibrosis caused by adjuvant arthritis were reverted to normal status in the combined therapy group in contrast to losartan and methotrexate monotherapies. In conclusion, methotrexate and losartan combined therapy provided more effective anti-inflammatory and hepatoprotective effects than either drug alone.