This review summarizes the current knowledge of condensed tannins (proanthocyanidins), their chemical structure, classification and biological effects. These compounds are widely distributed in higher plants and are an important part of the human diet. Recent interest in these substances has been stimulated by their potential health benefits, which are believed to arise mainly from their antioxidant activity. The mechanisms of their antioxidation action, like free radical scavenging activity, chelation of transition metals and inhibition of prooxidative enzymes and lipid peroxidation are discussed. Health prevention properties like anticarcinogenic, cardiovascular system preventing and antiinflammatory effects of proanthocyanidins are also presented. Their health benefit is promising, but additional research on the mechanism of action and metabolic fate after consumption of proanthocyanidins is required.
Proces stárnutí je předmětem zájmu mnoha vědních oborů. Život mnohobuněčného organizmu je udržován rovnováhou mezi produkcí nových buněk a zánikem starých. Celý tento proces je řízen řadou faktorů, regulačních mechanizmů. Ve stáři dochází k určitým změnám v oblasti antioxidační kapacity, metabolizmu mastných kyselín a biosyntězy cholesterolu. Studiem těchto změn bychom mohli přispět k podačení nepříznivého účinku aktivních forem kyslíku a zpomalení procesu stárnutí.
The process of ageing has been the focus of many research disciplines. A multicellular organism is kept alive through a balance of new cell production and old cell decay. There are a number of factors - regulating mechanisms controlling the whole process. Old age is characterized by certain changes as to antioxidant capacity, fatty acid netabolism and cholesterol biosynthesis. Research into these changes may help to suppress the undesirable effect of free oxygen radicals and slow down the process of ageing.
- MeSH
- Apoptosis genetics immunology drug effects MeSH
- Cholesterol biosynthesis MeSH
- Homeostasis physiology genetics immunology MeSH
- Humans MeSH
- Lipids MeSH
- Lipid Metabolism MeSH
- Reactive Oxygen Species adverse effects MeSH
- Aging physiology immunology metabolism MeSH
- Vitamins therapeutic use MeSH
- Check Tag
- Humans MeSH
Autori podávajú kritickú analýzu súčasných poznatkov o oxidačnom strese a o aktivite antioxidačných systémov u chorých s chronickými chorobami obličiek so zvláštnym zreteľom na hemodialyzovaných chorých. Napriek tomu, že prítomnosť zvýšeného oxidačného stresu u týchto chorých je dobre dokumentovaná, mnohé otázky ostávajú otvorené. V prehľade je opísaná patobiochémia oxidačného stresu pri hemodialýze, analýza súčasných poznatkov o lipidovej peroxidácii a aktivite antioxidačných enzýmov v červených krvinkách pri týchto ochoreniach. Na záver autori hodnotia názory na opodstatnenosť exogénnej suplementácie antioxidačnými vitamínmi u chorých na hemodialýze. Konštatujú, že zatiaľ jedinou dokázanou možnosťou zníženia oxidačného stresu pri hemodialýze je používanie membrán s obsahom vitamínu E.
The authors present a critical analysis of current knowledge on oxidative stress and on the activity of antioxidative systems in patients with chronic kidney disease with a focus on haemodialysed patients. Even though oxidative stress in these patients is well documented, a number of questions remain unanswered. The overview describes pathobiochemistry of oxidative stress during haemodialysis, analysis of current knowledge on lipid peroxidation and antioxidant enzyme activity in the red blood cells in patients with this disease. Finally, the authors evaluate opinions on justifiability of exogenous supplementation of vitamins with antioxidant properties in patients on haemodialysis. They conclude that the use of vitamin E-containing membranes is the only evidenced option for reducing oxidative stress during haemodialysis.
- MeSH
- Antioxidants * therapeutic use MeSH
- Biomarkers blood MeSH
- Kidney Failure, Chronic * physiopathology MeSH
- Renal Dialysis * instrumentation adverse effects MeSH
- Ascorbic Acid therapeutic use MeSH
- Humans MeSH
- Oxidative Stress * MeSH
- Superoxide Dismutase therapeutic use MeSH
- Vitamin E therapeutic use MeSH
- Check Tag
- Humans MeSH
Cieľom našej štúdie bolo zistiť, aký je vzťah medzi aktivitou antioxidantov a hladinami proteínov akútnej fázy zápalu u pacientov s akútnou exacerbácion chronickej obštrukčnej choroby pľúc. Súbor vyšetrených tvorili 30 pacienti, ktorí boli rozdelení do dvoch skupín podla aktivity erytrocytárnej katalázy (KAT). V súbore pacientov so zvýšenou aktivitou KAT sme zistili vyššie plazmatické hodnoty orosomukoidu (ORM) (p < 0,007) a ceruloplazmínu (CP) (p < 0,02) v porovnaní s pacientmi s normálnou aktivitou KAT. Medzi aktivitou KAT a ORM sme zistili signifikantnú lineárnu koreláciu (r = 0,58; p = 0,0006). Analogický vzťah sme našli medzi aktivitou KAT a CP (r = 0.49; p = 0,005). Výsledky našej štúdie ukazujú, že u pacientov s chronickou obštrukčnou chorobou pľúc existuje úzky vzťah medzi erytrocytárnou aktivitou antioxidantov a plazmatickými hladinami proteínov akútnej fázy zápalu.
The purpose of our study was to establish the relation of antioxidant activity and of the levels of proteins of the acute phase of infiammation in patients presenting an acute exacerbation of chronic obstructive pulmonary disease. We investigated a set of 30 patients, divided into two groups according to the activity of erythrocytic catalase (CAT). In patients with a higher CAT activity we found higher plasma values of orosomucoid (ORM) (p < 0.007) and of ceruloplasmin (CP) (p < 0.02) than in patients with normal CAT activity. We saw a significant linear correlation (r = 0.58; p = 0.0006) between CAT activity and ORM. We saw a similar relatonship of CAT activity and of CP (r = 0.49; p = 0.005). It appears from our results that in patients presenting with a chronic obstructive pulmonary disease there is a close relationship between erythrocytic antioxidant activity and plasma levels of the proteins of the active phase of inflammation.
1 online zdroj
- MeSH
- Antioxidants * MeSH
- Publication type
- Periodical MeSH
- Conspectus
- Biochemie. Molekulární biologie. Biofyzika
- NML Fields
- biochemie
[1st ed.] 457 s.
Methods in enzymology ; Vol.299
506 s.
- MeSH
- Antioxidants MeSH
- Oxidants MeSH
- Conspectus
- Biochemie. Molekulární biologie. Biofyzika
- NML Fields
- biochemie
[1st ed.] xxiv, 562 s. : il.
- Conspectus
- Obecná genetika. Obecná cytogenetika. Evoluce
- NML Fields
- genetika, lékařská genetika
- biologie
