Bone mineral density and vitamin d receptor polymorphism in beta-thalassemia major

Osteoporosis is the most prevalent bone complication in beta-thalassemic patients despite regular transfusions and iron chelation therapy. Although its etiology is multi-factorial, genetic factors play an important role in pathogenesis. These factors have not yet been clearly defined, however, osteoporosis may be related to vitamin D receptor gene BsmI polymorphism. In this study, BsmI vitamin D receptor gene polymorphism was analyzed using polymerase chain reaction and BsmI restriction fragment length polymorphism in 42 regularly treated- beta-thalassemic patients of different ages. Bone mineral density was measured by peripheral quantitative ultrasound at the heel of the foot. Serum levels of alkaline phosphatase, calcium, phosphorus, ferritin and 25-hydroxyvitamin D[3] were determined. Patients were divided into two groups according to pubertal signs: group I [22 children], and group II [20 adolescents and adults]. The Z-scores of bone mineral density in both groups were -1.32 +/- -0.9 and -2.30 +/- -1.02 respectively, with a significant difference between the two groups. The height standard deviation and 25-hydroxyvitamin D[3] were significantly decreased in group II compared to group I. Moreover, significantly lower bone mineral density and height standard deviation were detected among patients with BB vitamin D receptor genotype. Therefore, this genotype may be considered as a risk factor for osteoporosis in p-thalassemic patients

Potential antidiabetic and hypolipidemic effects of propolis extract in streptozotocin-induced diabetic rats

Free radicals have been implicated in the pathogenesis of diabetes mellitus leading to various complications including atherosclerosis. Propolis was reported to have oxygen radical scavenging activity. The present study was designed to investigate the possible antidiabetic, hypolipidemic and antioxidant effects of ethanolic extract of propolis [EEP]. Type[2] diabetes was induced in rats by injection of streptozotocin [STZ] in a dose of 60 mg/kg bwt, i.p. for 3 consecutive days. After 5 weeks of STZ injection, there were an apparent reduction in the animal body weight amounting to 21% and significant increases in serum glucose [184%], triglycerides [63%], total cholesterol [43%] and low density lipoprotein-cholesterol [LDL-C] [148%] with a concomitant decrease in serum high density lipoprotein-cholesterol [HDL-C] [51%] as compared to the control normal group. In addition, there was significant elevation in pancreatic lipid peroxides measured as malondialdehyde [MDA] and serum nitric oxide [NO] amounting to 185% and 224%, respectively with marked reduction in serum reduced glutathione [GSH] andcatalase [CAT] [66% and 31%, respectively] and pancreatic superoxide dismutase [SOD] [54%] in STZ-treated rats. On the other hand, oral daily treatment of animals with EEP in a dose of 200mg/kg bwt for a period of 5 weeks ameliorated STZ-induced alterations in the animal body weight as well as in serum glucose, lipids, lipoproteins, NO, GSH and CAT and pancreatic MDA and SOD. In conclusion, propolis extract offers promising antidiabetic and hypolipidemic effects that may be mainly attributed to its potent antioxidant potential. Further studies will be needed in future in order to determine which one[or more] of its active constituents has the main antidiabetic and hypolipidemic effects

Experimental diabetic nephropathy can be prevented by propolis: effect on metabolic disturbances and renal oxidative parameters

Oxidative stress may play a key role in the pathogenesis of diabetic nephropathy. Propolis and its extract have antioxidant properties. The effect of ethanolic extract of propolis against experimental diabetes mellitus-associated changes was examined. Diabetes was induced experimentally in rats by i.p. injection of streptozotocin [STZ] in a dose of 60 mg/kg bwt for 3 successive days. Blood urea nitrogen [BNU], creatinine, glucose, lipid profile, malondialdehyde [MDA] and urinary albumin were measured. Superoxide dimutase [SOD], glutathione [GSH], catalase [CAT] and MDA were measured in the renal tissue. The results showed decreased body weight and increased kidney weight in diabetic animals. Compared to the control normal rats, diabetic rats had higher blood glucose, BNU, creatinine, total cholesterol, triglycerides, low-density lipoprotein-cholesterol [LDL-C], MDA and urinary albumin and lower high-density lipoprotein-cholesterol [HDL-C] levels. Moreover, renal tissue MDA was markedly increased while SOD, GSH and CAT were significantly decreased. Oral administration of propolis extract in doses of 100,200 and 300 mg/kg bwt improved the body and kidney weights, serum glucose, lipid profile, MDA and renal function tests. Renal GSH, SOD and CAT were significantly increased while MDA was markedly reduced. These results may suggest a strong antioxidant effect of propolis which can ameliorate oxidative stress and delay the occurrence of diabetic nephropathy in diabetes mellitus

L-arginine augments the antioxidant effect of garlic against acetic acid induced ulcerative colitis in rats

Garlic contains many sulfhydryl compounds that act as antioxidants. However, the role of nitric oxide [NO] in inflammation is controversial. The aim of the present study is to investigate the possible protective effect of garlic against acetic acid-induced ulcerative colitis in rats, as well as the probable modulatory effect of L-arginine [NO precursor] on garlic activity. Intra-rectal inoculation of rats with 4% acetic acid for 3 consecutive days caused a significant increase in the colon weight and marked decrease in the colon length. In addition, acetic acid induced a significant increase in serum levels of nitrate as well as colonic tissue content of malondialdehyde [MDA]. Moreover, colonic tissue contents of glutathione [GSH], superoxide dismutase [SOD] and catalase [CAT] were markedly reduced. On the other hand, pre-treatment of rats with garlic [0.25g/kgbwt, orally] for 4 consecutive weeks and 3days during induction of colitis significantly reduced the increase in the colon weight induced by acetic acid and ameliorated alterations in oxidant and antioxidant parameters. Interestingly, oral co-administration of garlic [0.25g/kgbwt] and L-arginine [625mg/kgbwt] for the same period of garlic administration mitigated the changes in both colon weight and length induced by acetic acid and increased garlic effect on colon tissue contents of MDA and GSH. In conclusion, L-arginine can augment the protective effect of garlic against ulcerative colitis; an effect that might be mainly attributed to its NO donating property resulting in enhancement of garlic antioxidant effect. Further studies will be needed to determine which one of the active ingredients of garlic has the main antioxidant effect to be used with L-arginine

Hesperidin, an antioxidant flavonoid, prevents acrylonitrile-induced oxidative stress in rat brain

Acrylonitrile [ACN] is a volatile, toxic liquid used as a monomer in the manufacture of synthetic rubber, styrene plastics, acrylic fiber and adhesives. ACN is a potent neurotoxin. A role for free radical-mediated lipid peroxidation in the toxicity of ACN has been suggested. We examined the ability of hesperidin, an antioxidant flavonoid, to attenuate ACN-induced alterations in lipid peroxidation in rat brains. The daily oral administration of ACN to male albino rats in a dose of 50 mg/kg bwt for a period of 28 days produced a significant elevation in brain lipid peroxides measured as malondialdehyde [MDA] amounting to 107%, accompanied by a marked decrease in brain reduced glutathione [GSH] content reaching 63%. In addition, ACN administration resulted in significant reductions in the enzymatic antioxidant parameters of brain; superoxide dismutase [SOD], catalase [CAT], glutathione peroxidase [GSH-Px] and glutathione-S-transferase [GST] recording 43%, 64%, 52% and 43%, respectively. On the other hand, pretreatment with hesperidin and its co-administration with ACN once daily in a dose of 200 mg/kg bwt, i.p. for 28 days ameliorated ACN-induced alterations in brain lipid peroxidation. These results suggest that hesperidin may have a beneficial role against ACN-induced oxidative stress in brain; an effect that is mainly attributed to the antioxidant property of hesperidin