Name/ Lamiaa Fathy Asal Specialization / poultry Advisor / prof .Dr Hassan saber zeweil

The biological role of antioxidants for decreasing the damage impact of free radicals in rabbits

Introduction

What are Free Radicals? A free radical is an unstable molecule that loses one of its electrons and therefore becomes unbalanced and highly reactive. Free radicals damage healthy cells and in turn impair the body’s normal functions.

How are Free Radicals Produced? normal respiration metabolism exposure to air pollutants sun exposure radiation from X-rays drugs viruses bacteria parasites dietary fats stress injury

PHYSIOLOGICAL EFFECTS Free radicals have been implicated as playing a role in the etiology of cardiovascular disease, cancer, Alzheimer's disease, and Parkinson's disease. Harmful free radicals are toxic molecules of oxygen that damage every area of our bodies. One free radical can initiate tens of thousands of chain reactions that cause tremendous harm (destroy cell membranes, disrupt crucial processes in the body, reprogram DNA, form mutant cells, and more).

MEASUREMENT OF FREE RADICALS When a fatty acid is peroxidized it is broken down into aldehydes, which are excreted. Aldehydes such as thiobarbituric acid reacting substances (TBARS) have been widely accepted as a general marker of free radical production. The most commonly measured TBARS is malondialdehyde (MDA)

ANTIOXIDANT DEFENSES Antioxidant means "against oxidation." Antioxidants work to protect lipids from peroxidation by radicals. Antioxidants are effective because they are willing to give up their own electrons to free radicals. When a free radical gains the electron from an antioxidant it no longer needs to attack the cell and the chain reaction of oxidation is broken (4). After donating an electron an antioxidant becomes a free radical by definition. Antioxidants in this state are not harmful because they have the ability to accommodate the change in electrons without becoming reactive. The human body has an elaborate antioxidant defense system. Antioxidants are manufactured within the body and can also be extracted from the food humans eat such as fruits, vegetables, seeds, nuts, meats, and oil. There are two lines of antioxidant defense within the cell. The first line, found in the fat-soluble cellular membrane consists of vitamin E, beta-carotene, and coenzyme Q (10). Of these, vitamin E is considered the most potent chain breaking antioxidant within the membrane of the cell. Inside the cell water soluble antioxidant scavengers are present. These include vitamin C, glutathione peroxidase, superoxide dismutase (SD), and catalase. Only those antioxidants that are commonly supplemented (vitamins A, C, E and the mineral selenium)

An in vitro study on reproductive toxicity of aluminium chloride on rabbit sperm: The protective role of some antioxidants Mokhtar I. Yousef a,∗, Kamel I. Kamelb, Marwa I. El-Guendi a, Fatma M. El-Demerdash a a Department of Environmental Studies, Institute of Graduate Studies and Research, Alexandria University, 163 Horreya Avenue, P.O. Box 832, El-Chatby, Alexandria 21526, Egypt b Animal Production Research Institute, Dokki, Giza, Egypt Received 11 April 2007; received in revised form 10 July 2007; accepted 11 July 2007 Available online 17 July 2007

EXPERIMENTAL design With vit c (1mMol ) With vit E(2mMol) Without vit Positive control 1mMol AlCl3 5 mMol AlCl3 10 mMol AlCl3 15 mMol AlCl3 20 mMol AlCl3 Positive control 1mMol AlCl3 5 mMol AlCl3 10 mMol AlCl3 15 mMol AlCl3 20 mMol AlCl3 Negative control 1mMol AlCl3 5 mMol AlCl3 10 mMol AlCl3 15 mMol AlCl3 20 mMol AlCl3

Results

Fig. 1. Changes in motility (%) and viability (%) of rabbit sperm at 0, 2 and 4 h of incubation with AlCl3 alone or with vitamin C (Vit. C 1mM) (mean±S.E.). Asterisk (*) indicates significant (p < 0.05) effect of treatment with AlCl3 alone compared to control without Vit. C or in combination with Vit. C compared to control with Vit. C.

Fig. 2. Changes in motility (%) and viability (%) of rabbit sperm at 0, 2 and 4 h of incubation with AlCl3 alone or in combination with vitamin E (Vit. E 2mM) (mean±S.E.). Asterisk (*) indicates significant (p < 0.05) effect of treatment with AlCl3 alone compared to control without Vit. E or in combination with Vit. E compared to control with Vit. E.

Fig. 3. Changes in TBARS levels and activities of SOD, CAT, ALT, AST and ACP in rabbit sperm after 2 h incubation with AlCl3 alone or in combination with vitamin C (Vit. C; 1mM) (mean±S.E.). Asterisk (*) indicates significant (p < 0.05) effect of treatment with AlCl3 alone compared to control without Vit. C or in combination with Vit. C compared to control with Vit. C.

Fig. 4. Changes in TBARS levels, activities of SOD,CAT, AST,ALT andACP in rabbit sperm after 2 h incubation with AlCl3 alone or in combination with vitamin E (Vit. E 2mM) (mean±S.E.). Asterisk (*) indicates significant (p < 0.05) effect of treatment with AlCl3 alone compared to control without Vit. E or in combination with Vit. E compared to control with Vit. E.

Fig. 5. Changes in TBARS levels and activities of SOD, CAT, AST, ALT and ACP in rabbit sperm after 4 h incubation with AlCl3 alone or in combination with vitamin C (Vit. C 1mM) (mean±S.E.). Asterisk (*) indicates significant (p < 0.05) effect of treatment with AlCl3 alone compared to control without Vit. C or in combination with Vit. C compared to control with Vit. C.

Fig. 6. Changes in TBARS levels, activities of SOD,CAT, AST,ALT andACP in rabbit sperm after 4 h incubation with AlCl3 alone or in combination with vitamin E (Vit. E 2mM) (mean±S.E.). Asterisk (*) indicates significant (p < 0.05) effect of treatment with AlCl3 alone compared to control without Vit. E or in combination with Vit. E compared to control with Vit. E.

Conclusion

the obtained results showed that aluminium chloride exerted reproductive toxicity in a dose and time-dependent manner on rabbit sperm in vitro. Aluminium chloride increased TBARS level, and changed the activities of antioxidant enzymes, transaminases and acid phosphatase. It also caused a decline in sperm motility and viability more likely through other mechanisms than oxidative injury, which require more investigation. The use of vitamin C or vitamin E disturbing effects on free radicals level and enzymatic activity, but not on motility and viability.

Antioxidant activities and lipid lowering effects of isoflavone in male rabbits Mokhtar I. Yousef a,*, Kamel I. Kamel b, Alshaimaa M. Esmail a, Hoda H. Baghdadi a a Department of Environmental Studies, Institute of Graduate Studies and Research, Alexandria University, 163, Horreya Avenue, P.O. Box 832, Alexandria 21526, Egypt b Animal Production Research Institute, P.O. Box 12618, Dokki, Giza, Egypt Received 27 October 2003; accepted 19 April 2004 Abstract

EXPERIMENTAL Diets Control 6 rabbits 2.5 mg isoflavones /kg B.W

Results

Fig. 1. Changes in plasma thiobarbituric acid-reactive substances (TBARS) and glutathione S-transferase (GST) during treatment of male rabbits with either 2.5 or 5 mg/kg B.W. doses of isoflavone.

Table 1:Thiobarbituric acid-reactive substances (TBARS) and glutathion-Stransferase (GST) activity in plasma, liver, testes and brain during treatment of male rabbits with either 2.5 or 5 mg/kg doses of isoflavones Parameter Isoflavones Control 2.5 mg/kg 5 mg/kg Plasma TBARS (nmol/ml) 1.82±0.06a 1.16±0.07b 1.15±0.08b GST (μmol/h) 0.53±0.007a 0.53±0.006a 0.53±0.005a Liver TBARS* 14.06±0.99a 11.5±0.15b 10.3±1.78b GST** 1.04±0.007a 1.05±0.032a 1.04±0.020a Testes 12.01±0.31a 7.25±0.1.60b 9.45±0.46ab 0.51±0.09a 0.51±0.011a 0.49±0.004a Brain 36.1±2.67a 31.9±4.18ab 24.3±1.6b 0.49±0.003a Kidney 11.8±5.78a 7.3±4.05b 9.5 ±3.75ab 0.56±0.006a 0.54±0.013a 0.57±0.008a Values are expressed as overall means±SE; n ¼ 6 for each treatment group. abWithin row overall mean with different superscript letter differ significantly (P < 0:05). *TBARS is expressed as nmol/g tissue. **GST specific activity: lmol/h/mg protein.

Table 2: Plasma lipid and lipoprotein profiles during treatment of male rabbits with either 2.5 or 5 mg/kg doses of isoflavones Lipids (mg/dl) Isoflavones Control 2.5 mg/kg 5 mg/kg TL 557±38.7a 459±15.4b 440±17.9b Cholesterol 152±2.1a 122±1.9b 121±2.3b TG 168.6±7.8a 139.1±4.8b 129.7±2.7c HDL 34.9±0.33b 44.4±0.67a 45.5±0.89a LDL 108±2.4a 87±2.0b 84±2.2b VLDL 33.7±1.56a 27.8±0.97b 25.9±0.53b LDL:HDL ratio 3.1 ±0.08a 2.0±0.06b 1.9±0.08b Cholesterol (% TL) 30.1±2.79a 28.8±1.01a 29.2±1.13a Values are expressed as overall means±SE; n ¼ 6 rabbits for each treatment group. abcWithin row, means with different superscript letters differ significantly (P < 0:05). TL: total lipids, TG: triglycerides, HDL: high density lipoprotein, LDL: low density lipoprotein, VLDL: very low density lipoprotein

Fig. 2. Changes in plasma total lipids, cholesterol and triglycerides during treatment of male rabbits with either 2.5 or 5 mg/kg B.W. doses of isoflavone.

Fig. 3. Changes in plasma high density lipoproteins (HDL), low density lipoproteins (LDL), very low density lipoproteins (VLDL) and LDL:HDL ratio during treatment of male rabbits with either 2.5 or 5 mg/kg B.W. oses of isoflavone.

Conclusion

The results of the present study led to the conclusion that isoflavone dosages (2.5 or 5 mg/kg body weight), which is more than two or four times to the amounts consumed (40 mg) in many Eastern nations (Adlercreutz et al., 1995), have beneficial effect on plasma lipid and lipoprotein concentrations, TBARS level and antioxidant activities in rabbits. Also, the 5 mg/kg dose of isoflavones was more effective than the 2.5 mg/kg dose on lipids and lipo-protein profiles, but more studies would help to confirm the optimal amount required. Therefore, the animal’s diet must contain an adequate level of soybean, which covers the isoflavones requirements

COMBINED THERAPY WITH ANTIOXIDANTS AGAINST CADMIUM INDUCED TESTICULAR DYSFUNCTION IN RABBITS Magda M. ElTohamy National Research Center, Department of Animal reproduction& AI, Cairo, Egypt

EXPERIMENTAL Diets Control Cadmium Cadmium 12 rabbits 12 rabbits &Antioxidants 12 rabbits

Results

Table 1 Serum parameters of rabbits received cadmium and cadmium and antioxidants. Control Cadmium &Antioxidants AST (U/L) 91.5 ±4.6a 205.9±8.9© 8.15±133.2a ALT(U/L) 1.6± 0.22a 4.99±1.1© 2.37±0.5 a GGT (U/L) 14.9± 1.3a 25.9±1.7© 15.5± 2.7 a LDH (U/L) 1303±69.9a 1177±40.5© 1225±81a ALP (U/L) 1732±101a 1800±199 © 1715±211 a GST((nmol/ml blood x10 0.66±0.04a 0.81±0.04 © 0.59±0.02 a Different superscripts in row indicates significantly different means at(P <0.05).

Table 2 Testicular parameters of rabbits received cadmium and Cadmium and antioxidants. Control Cadmium Cadmium and antioxidants Cd concen. (ug/gm tissue) 0.35±0.04ª 39.33±6.66© 0.33±0.03ª LPO (nmol/gm 142.66±8.5ª 403.76±12.3 © 139.45±7.6ª AcP (IU/mg) 566.0±7.7ª 513.8±8.65© 592.22±32.8ª ALP (IU/mg) 988.32±34.8 ª 867.4±16.6© 122.6±16.8ª LDH (IU/mg) 2110±23.3ª 2860±43.2 © 1992±36.7ª AST (IU/mg) 59.9±2.0ª 48.9±2.33© 58.6±1.65ª ALT (IU/mg) 16.6±4.3ª 12.7±8.8© 18.4±8.6ª SOD (IU/mg) 165.5±22.5ª 99.8±13.3© 177.0±24.6ª GST(IU/mg) 0.35±0.02ª 3.6±0.9© 0.30±0.9ª Different superscripts in row indicates significantly different means at (P < 0.05)

Table 3.GSH-Px, GR, activities in red blood cells, GST in the plasma and GSH in whole blood in the three groups. Parameters Control Cadmium Cadmium and antioxidant GSH-Px(nmol/mlblood x10) 22.0 ± 3.6 ª 34.0 ± 7.4 © 24.0 ± 2.02 ª GR (nmol/ml blood X10) 29.7 ± 4.3 ª 40.0 ± 5.8 © 31.2 ± 6.4 ª GST (nmol/ml bloodX10 34.8 ± 3.2 ª 41.84 ± 1.97 © 28.9 ± 3.31ª GSH (nmol/mlX10 9.9 ± 0.6 ª 13.0 ± 1.72 © 10.2 ± 1.7 ª Different superscripts in row indicate significantly different means at(P < 0.05).

Conclusion

the antioxidant used is effective in combating celldamaging free radicals, which are known to contribute towards testicular dysfunction. Studies have shown that antioxidants are uniquely different from one another and each have a specific function in the body. They are also synergistic, and will work most effectively when they are used together. These combinations can perform a wide range of metabolic activities, free radical scavenging and preventive actions. The present antioxidant formula used as a blend of antioxidants specifically designed to assist the body in overcoming a vast array of physiological stressors and to help avert the effects of Cd-induced testicular dysfunctions.