The investigation of the effects of structurally different saponin containing plants on DNA damage, protein oxidation, lipid peroxidation and some biochemical parameters on experimentally induced diabetic rats

XIVSUMMARYThe Investigation Of The Effects Of Structurally Different SaponinContaining Plants On DNA Damage, Protein Oxidation, Lipid PeroxidationAnd Some Biochemical Parameters On Experimentally Induced DiabeticRatsA.Fatih FİDANIn this thesis, the effects of diet suplementation with different types of saponincontaining plant sources such as Yucca schidigera in streoid type saponin orQuillaja saponaria in triterpenoid type saponin or mixture of both plants wereinvestigated on experimentally induced diabetic rats. Experimental diabetes wasapplied by intraperitoneal injection of 50 mg/kg streptozotosin. The blood glucoselevels around 200 mg/dl and higher were considered as diabetic. Animals wereallocated into 5 groups of each containing 10 rats.Non-diabetic control group (K) and diabetic control group (D) were fed bystandart rat feed. The Yucca schidigera group (DY) by standart rat feed+100ppm Yucca schidigera powder (Sarsaponin 30®), Quillaja saponaria group (DQ)by standart rat feed+100 ppm Quillaja saponaria powder (Nutrafito®) and mixgroup (DQY) by standart rat feed+100 ppm Yucca schidigera Quillaja saponariapowder (Nutrafito Plus®) were fed ad libitum for 3 weeks during the study.In this study, the profile of body weight was decreased in diabetic rats comparedto non-diabetic control group (p <0.01). It was observed that diabetic groupsconsumed more water than non-diabetic control group, however, waterconsumption of DY and DQ groups were less when compared to D and DQYgroups. It was seen that in diabetic rats, the increased level of blood glucose waslower in DY and DQ groups than in D and DQY groups (p <0.001). Thedecreased levels of insulin in diabetic groups were increased in DY and DQYgroups (p <0.05), moreover the level of the DQY group almost reached the non-diabetic control group level. In diabetic rats T-cholesterol levels in DY, DQ andDQY groups were found to be decreased compared to D group (p <0.01) and itwas dropped below non-diabetic control group level in DY and DQ groups.Furthermore high trigliserid levels significantly decreased in DY, DQ and DQYgroups (p <0,001). Decreased levels of HDL-cholestrol in diabetic groups werehigher in DQ and DQY groups (p <0.05), whereas DQ group exceeded level ofXVnon-diabetic control group. LDL-cholestrol levels showed non-significantdecrease in DY, DQ and DQY groups. MDA, an oxidative stress parameter, is aresult of increased blood glucose level in diabetic animals, was decreasedsignificantly in DY, DQ and DQY groups rather than in D group (p <0.001).Increased levels of DNA damage of mononuclear leukocytes in D group weredecreased in DY, DQ and DQY groups (p <0.001). In addition DQ group levelwas as low as at the non-diabetic control group level. Although protein oxidationlevel was increased in diabetic groups, it was decreased in DY, DQ and DQYgroups and dropped in DQ and DQY groups as low as at the non-diabetic controlgroup level. Low level of NO in diabetic rats was increased in DQ group (p<0.01). Levels of total antioxidant capacity between groups were higher in D, DYand DQY group than those in non-diabetic control group, however it was lower inDQ group then non-diabetic control group, but these changes were found to benonsignificant.This study indicated that Yucca schidigera and Quillaja saponaria can be used forthe regulation of increased blood glucose level and disturbed lipid metabolism ormodification of metabolic parameters as treatment support entity. Combined useof Yucca schidigera and Quillaja saponaria deppressed the antihyperglycemiceffects on diabetes mellitus when applied seperatelly for each plant. This mightindicate that these plants may have antagonist mechanism on the glucosemetabolism when used together. Thus more detailed studies are needed towardsthe understanding of the mechanism.Our findings suggest that Quillaja saponaria seemed to be more effective thanYucca schidigera on balancing the negative effects of increased oxidative stressand preventing or diminishing diabetic complications in diabetes mellitus.As a result, hyperglisemie could be modarately repressed by adding mentioneddoseges of Quillaja saponaria and Yucca schidigera powders in diets of diabeticanimals. Moreover, it can be considered that these plants could support thetreament at every stage of the disease by hypocholestrolemic and antioxidanteffects.Key words: Diabetes Mellitus, Yucca schidigera, Quillaja saponaria, OxidativeStres, DNA Damage