ABSTRACT
We resequenced and phased 27 kb of DNA within 580 kb of the MHC class II region in 158 population chromosomes, most of which were conserved extended haplotypes (CEHs) of European descent or contained their centromeric fragments. We determined the single nucleotide polymorphism and deletion-insertion polymorphism alleles of the dominant sequences from HLA-DQA2 to DAXX for these CEHs. Nine of 13 CEHs remained sufficiently intact to possess a dominant sequence extending at least to DAXX, 230 kb centromeric to HLA-DPB1. We identified the regions centromeric to HLA-DQB1 within which single instances of eight "common" European MHC haplotypes previously sequenced by the MHC Haplotype Project (MHP) were representative of those dominant CEH sequences. Only two MHP haplotypes had a dominant CEH sequence throughout the centromeric and extended class II region and one MHP haplotype did not represent a known European CEH anywhere in the region. We identified the centromeric recombination transition points of other MHP sequences from CEH representation to non-representation. Several CEH pairs or groups shared sequence identity in small blocks but had significantly different (although still conserved for each separate CEH) sequences in surrounding regions. These patterns partly explain strong calculated linkage disequilibrium over only short (tens to hundreds of kilobases) distances in the context of a finite number of observed megabase-length CEHs comprising half a population's haplotypes. Our results provide a clearer picture of European CEH class II allelic structure and population haplotype architecture, improved regional CEH markers, and raise questions concerning regional recombination hotspots.
Subject(s)
Adaptor Proteins, Signal Transducing/genetics , Haplotypes , Major Histocompatibility Complex/genetics , Nuclear Proteins/genetics , Base Sequence , Chromosomes, Human, Pair 6 , Co-Repressor Proteins , Conserved Sequence , Genes, Dominant , HLA-DP beta-Chains/genetics , HLA-DQ Antigens/genetics , HLA-DQ beta-Chains/genetics , Humans , Linkage Disequilibrium , Molecular Chaperones , Mutation , Polymorphism, Single Nucleotide , Recombination, Genetic , White People/geneticsABSTRACT
PURPOSE: Oxidative stress in diabetes coexists with a reduction in the antioxidant status; which can increase the deleterious effects of free radicals. Many plant extracts and plant products have been shown to have significant antioxidant activity. The role of antioxidant plants in diabetes has not been studied. Food additives like spices; which have free radical scavenging activity; may also be useful in maintaining normal glucose levels in diabetic patients. The objective of the study is to evaluate the aqueous extracts of selected umbelliferous fruits for hypoglycaemic and antidiabetic activities in normal and diabetic rats respectively. METHODS: All the aqueous extracts of (Caraway) CA; (Coriander) CO; (Cumin) CU; (Dill) DI and (Fennel) FE were administered at dose levels of 300 mg/kg body weight orally to different groups each containing 5 animals. A control group was also maintained simultaneously and received distilled water orally.Blood samples were collected from retro-orbital plexus of each rat before and at 2; 4; 6 and 8 h after extract administration and were analyzed for glucose content by using glucose oxidase peroxidase (GOD-POD) method using a visible spectrophotometer at 505 nm. RESULTS: In normal rats only caraway extract produced significant hypoglycaemic action. The rest of the extracts produced hypoglycaemia; which was not significant different from that of control animals. In diabetic rats also the caraway was found to be the best among the extracts. CONCLUSION: The study indicates that since the umbelliferous fruits are used in the preparation of foods; they may be useful in the control of postprandial rise of blood glucose particularly in diabetic condition. Additionally; their daily use may help in reducing complications associated with chronic diabetes
Subject(s)
Antioxidants , Apiaceae , Blood Glucose , Diabetes Mellitus , Glucose Oxidase , Oxidative StressABSTRACT
The antioxidant activity of the aqueous extracts of five umbelliferous fruits--caraway (Carum carvi), coriander (Coriandrum sativum), cumin (Cuminum cyminum), dill (Anethum graveolens) and fennel (Foeniculum vulgare)--were investigated in comparison with the known antioxidant ascorbic acid in in vitro studies. The amount of aqueous extract of these five umbelliferous fruits and ascorbic acid needed for 50% scavenging of superoxide radicals was found to be 105 microg (caraway), 370 microg (coriander), 220 microg (cumin), 190 microg (dill), 205 microg (fennel) and 260 microg (ascorbic acid). The amount needed for 50% inhibition of lipid peroxide was 2100 microg (caraway), 4500 microg (coriander), 4300 microg (cumin), 3100 microg (dill), 4600 microg (fennel) and 5000 microg (ascorbic acid). The quantity needed for 50% inhibition of hydroxyl radicals was 1150 microg (caraway), 1250 microg (coriander), 470 microg (cumin), 575 microg (dill), 700 microg (fennel) and 4500 microg (ascorbic acid). The daily use of the above fruits in various forms is very common in India and the present study revealed strong antioxidant activity of their extracts that was superior to known antioxidant ascorbic acid and indicate their intake may be beneficial as food additives.
