Důsledky a symptomy deficitu vitamínu C
Anaemia
- Common
- vitamin C may stabilise folate in food and in plasma
- Increased excretion of oxidized folate derivatives in human scurvy was reported [4]
- Vitamin C promotes absorption of soluble non-haem iron
- Chelation [4]
- Maintaining the iron in the reduced (ferrous, Fe2+) form [4]
- Can be achieved with the amounts of vitamin C in foods
- From 25 mg upwards
- Depends largely on the amount of inhibitors:
- Phytates
- Polyphenols in the meal [4]
Asociovaná onemocnění
- Poor VitC status is associated with increased all-cause mortality [3]
- Low plasma concentrations are reported in:
- Patients with diabetes
- Infections
- Smokers
- Diets with a high vitamin C content have been associated with
- Lower cancer risk
- Oral cavity
- Oesophagus
- Stomach
- Colon
- Lung
- no effect of consumption of vitamin C supplements on
- Development of colorectal adenoma
- Stomach cancer
- no consistent evidence from population studies
- Heart disease
- Cancers
- Cataract
Cévní stěny jsou křehčí, méně pevné
- Především vlásečnice
- Zvýšená krvácivost (krvácení dásní typické)
- Snadná tvorba modřin
- X syntézy kolagenu
Mírná hypovitaminóza
- Zpomalený růst
- Zvýšená kazivost zubů
- Narušení stavby kostí (v dětství osteomalacie)
- Krvácení do kloubů a jejich deformace
- Nedostatečná odolnost proti infekcím
- Zvýšená únava
- žaludeční problémy
- Lámavé vlásečnice
- Snížená tvorba mléka
- Formation of brown spots on the skin [12]
- Most abundant on the thighs and legs
- Spongy gums
- Bleeding from all mucous membranes
- Looks pale
- Feels depressed
- Partially immobilized [12]
Dětské kurděje
- Changes are mainly at the sites of most active bone growth
- Pseudoparalysis of the limbs
- By extreme pain on movement
- Caused by haemorrhages under the periosteum
- Swelling and haemorrhages in areas of the gums surrounding erupting teeth
Adult scurvy
- Early signs of clinical deficiency
- Collagen-related pathology
- Impaired wound healing
- Follicular hyperkeratosis [4]
- Petechial haemorrhages
- Swollen or bleeding gums
- Joint pain
- Very low concentrations of ascorbate in plasma, blood, or leukocytes [4]
- Anémie
- Krvácivost
- Otokem kloubů
- Krvácení z dásní
- Ztráta zubů
- Křehkost kostí
- Sterilita
- časté infekce
- Atrofie (oslabováním a prodlužování svalstva)
- žaludeční vředy
- 1700 objev UK loďstva, že lze kurdějům předcházet citrusovými plody
- 1930 izolace vit. C
- K prevenci kurdějí stačí cca 10mg vit. C/den
Extrémní hypovitaminóza (avitaminóza) = kurděje -scurvy = skorbut - advanced scurvy
- Gingival changes
- Pain in the extremities
- Haemorrhagic manifestations
- Preceded oedema
- Ulcerations
- Ultimately death
- Skeletal and vascular lesions in scurvy
- Failure of osteoid formation
- Open, suppurating wounds
- Loss of teeth
- Death
- Progressing to shortness of breath
- Bone pain
- Poor wound healing
- Fever
- Convulsions and eventual death
Terapie
- Until quite late in the disease the damage is reversible
- With vitamin C repletion, healthy collagen replaces the defective collagen
- Treatment can be orally or by intramuscular or intravenous injection
Human dietary studies of experimentally induced scurvy
- During World War II in Britain
- Iowa state prisoners in the late 1960s - 1980
- All obvious symptoms of scurvy induced by an experimental scorbutic diet
- Could be completely reversed by additional vitamin C supplementation of only 10 mg a day [12]
- no clinical difference between men given 70 mg / day
- Blood level of vitamin C of about 0.55 mg/dl
- About 1/3 of tissue saturation levels [12]
- 10 mg per day
- Men in the prison study
- First signs of scurvy about 4 weeks after starting the vitamin C-free diet
- British study, six to eight months were required
- Due to the pre-loading of this group with a 70 mg/day supplement for six weeks before [12]
- Body pool of less than 300 mg
- Daily turnover of only 2.5 mg/day
- Instantaneous half-life of 83 days by this time
- Elimination constant of 4 months [12]
Zvýšená citlivost CNS vůči hyperexcitaci glutamátem
- An increase in the susceptibility to excitotoxicity mediated by the NMDA glutamate receptor in mice with SVCT2 deficiency has also been shown [11]
Progrese nealkoholické steatozy jater - NAFLD progression
- May be accelerated by poor VitC status [3]
- Strongly associated with obesity, dyslipidemia, IR, oxidative stress, inflammation and the metabolic syndrome
- Prevalence of NAFLD in obese patients has been reported to be 74% [3]
- Deficiency per se promotes cellular oxidative stress, e.g., in the liver [3]
Vypadávání vlasů
- X vaziva a kolagenu,...
- + ox. stres
- Horší vstřebávání železa
- ...
Snížená pevnost vaziva
- Snížená pevnost vazivového aparátu zubu
- Viklání a vypadávání zubů typické pro kurděje
