Kyle J. Norton
The widespread of incidence of asthma over last 20 years in South East
Asian population, specially in children and aging group has caused some
concerns to the government and scientific community. It may be due to
over intake in artificial ingredients and polluted environment.
Vitamin A is a general term of Vitamin A Retinol, retinal, beta-carotene, alpha-carotene, gamma-carotene,
and beta-cryptoxanthin best known for its functions for vision health
and antioxidant scavenger and essential for growth and differentiation
of a number of cells and tissues.
Recommended intakes of vitamin A, according to the Institute of
Medicine of the National Academies (formerly National Academy of
Sciences) is 600 µg daily as extremely high doses (>9000 mg) can be
toxicity as causes of dry, scaly skin, fatigue, nausea, loss of
appetite, bone and joint pains, headaches, etc.
Epidemiological studies linking vitamin A in reduced risk and treatment
of asthma have been inconclusive(a)(b)(c)(d)(e), but according to the
University G. D'Annunzio, and Respiratory Pathophysiology Center,
dietary supplementation or adequate intake of lycopene and vitamin A rich foods may be beneficial in asthmatic subjects(f).
1. Retinols
Serum vitamin A concentrations was
found significantly lower in asthmatic subjects than healthy control
subjects and administration of all-trans retinoic acid, ATRA
dramatically attenuated airway inflammation through inhibiting Th2 and
Th17 differentiation and/or functions. according to the Ruijin Hospital
Affiliated to Shanghai Jiao Tong University School of Medicine(1).
ORMDL3 is a candidate gene of childhood onset asthma, and high-transcript of ORMDL3 is associated with the development of asthma. According to Nanjing Medical University, all-trans retinoic acid (ATRA) is an active metabolite of Vitamin A, reduced the risk of asthma through maintained airway epithelial integrity, inhibited asthma
effector cells differentiation, modulating immune response, possibly via
facilitates ORMDL3 production probable through PKA/CREB(2). Also in
all-trans retinoic acid, ATRA, the Tehran University of Medical Sciences
study suggested that ATRA diverted the human immune response in neutral
conditions (without adding polarizing cytokines) by increasing FOXP3+
cells and decreasing RORγt+ cells(3). In rats with asthma,
ATRA was found to alleviate airway hyperresponsiveness and airway
remodeling possibly through decreasing the protein expression of
MMP-9(4). The study at 1Inserm
U700 and Université Paris 7, in a mouse model of ovalbumin
(OVA)-induced T helper (Th) 2-type responses and airway remodeling,
indicated a effectiveness of liposomally encapsulated ATRA (Lipo-ATRA)
in exacerbates allergic immune and inflammatory responses, most
likely through promoting Th2 development(5).
Unfortunately, according to Johns Hopkins University, even though animal models suggest that vitamin A
deficiency affects lung development adversely and promotes airway
hyperresponsiveness, and may predispose to an increased risk of asthma, but vitamin A supplementation early in life was not associated with a decreased risk of asthma in an area with chronic vitamin A deficiency(6).
2. Carotenoids (beta-carotene, alpha-carotene, gamma-carotene and beta-cryptoxanthin)
Carotenoids, plant pigments, converted to vitamin A after intake, play
an important role in prevention and treatment of some diseases through
it antioxidant effects. In the study of the effect of vitamin intake
among asthmatic subject, researchers at the Hung Kuang University, found
that nutritional supplement therapy including beta carotene may improve
dysregulated oxidant and antioxidant status, inflammation and immune
responses, pulmonary function, and health-related quality of life in
patients with mild to moderate allergic asthma(7). The John Hunter Hospital study of asthmatic subjects with airway hyper-responsiveness (AHR), indicated a reduced levels of beta-carotene
and alpha-tocopherol compared with those without AHR, possibly due to
impaired antioxidant defences and are thus most susceptible to the
damaging effects of oxidative (8). Other researchers suggested that
the imbalance of antioxidants found in asthmatic patients may be the
possible causes of the disease(9) and modifying the dietary intake of carotenoids alters clinical asthma outcomes with improvements evident only through increased whole foods intake, not supplements(10)
But according to the study of Yamaguchi University, there was no significant association for asthma in Japanese youth(11) and the study of a total of 423 children from a rural area of Thailand, in a Health Interview for Asthma Control questionnaire, showed no correlation of dietary intake of carotenoids between asthmatic and non-asthmatic children(12).
Taken altogether, using vitamin A in prevention and treatment of
asthmatic patient remains controversial. According to the study in summarized the important of vitamin A in treatment of asthma, excessive intake of vitamin A may increase the risk or severity of asthma in industrialized countries whereas vitamin A deficiency continues to increase mortality from infectious diseases in developing countries(12)(13). Overdoses can lead to toxic symptoms. Please
make sure you follow the guideline of the Institute of Medicine of the
National Academies.
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References
(a) Diet and asthma: vitamins and methyl donors by Han YY1, Blatter J1, Brehm JM1, Forno E1, Litonjua AA2, Celedón JC3.(PubMed)
(b) Maternal intake of vitamins A, E and K
in pregnancy and child allergic disease: a longitudinal study from the
Danish National Birth Cohort by Maslova E, Hansen S, Strøm M,
Halldorsson TI, Olsen SF.(PubMed)
(c) Nutritional supplements and plasma antioxidants in childhood asthma by Fabian E1, Pölöskey P, Kósa L, Elmadfa I, Réthy LA.(PubMed)
(d) Nutritional supplement therapy improves oxidative stress, immune
response, pulmonary function, and quality of life in allergic asthma patients: an open-label pilot study by Guo CH1, Liu PJ, Lin KP, Chen PC(PubMed)
(e) Cod liver oil intake and incidence of asthma in Norwegian adults--the HUNT study by Mai XM1, Langhammer A, Chen Y, Camargo CA Jr.(PubMed)
(f) Plasma lycopene and antioxidant vitamins in asthma: the PLAVA study by Riccioni G1, Bucciarelli T, Mancini B, Di Ilio C, Della Vecchia R, D'Orazio N.(PubMed)
(1) All-trans retinoic acid attenuates airway inflammation by inhibiting Th2 and Th17 response in experimental allergic asthma by Wu J1, Zhang Y, Liu Q, Zhong W, Xia Z.(PubMed)
(2) All-trans retinoic acid modulates ORMDL3 expression via transcriptional regulation by Zhuang LL1, Huang BX, Feng J, Zhu LH, Jin R, Qiu LZ, Zhou GP.(PubMed)
(3) Effect of all-trans retinoic acid (ATRA) on viability,
proliferation, activation and lineage-specific transcription factors of
CD4+ T cells by Bidad K1, Salehi E, Oraei M, Saboor-Yaraghi AA, Nicknam MH.(PubMed)
(4) [Effects of all-trans retinoic acid on airway responsiveness and airway remodeling in rats with asthma].[Article in Chinese] by Li WK1, Li Y, Zhong LL.(PubMed)
(5) Liposomal retinoic acids modulate asthma manifestations in mice by Maret M1, Ruffie C, Periquet B, Campo AM, Menevret M, Phelep A, Dziewiszek K, Druilhe A, Pretolani M.(PubMed)
(6) Supplementation with vitamin A early in life and subsequent risk of asthma by Checkley W1, West KP Jr, Wise RA, Wu L, LeClerq SC, Khatry S, Katz J, Christian P, Tielsch JM, Sommer A.(PubMed)
(7) Nutritional supplement therapy improves oxidative stress, immune
response, pulmonary function, and quality of life in allergic asthma patients: an open-label pilot study by Guo CH1, Liu PJ, Lin KP, Chen PC.(PubMed)
(8) Reduced circulating antioxidant defences are associated with airway
hyper-responsiveness, poor control and severe disease pattern in asthma by Wood LG1, Gibson PG.(PubMed)
(9) Antioxidants, oxidative stress, and pulmonary function in individuals diagnosed with asthma or COPD by Ochs-Balcom HM1, Grant BJ, Muti P, Sempos CT, Freudenheim JL, Browne RW, McCann SE, Trevisan M, Cassano PA, Iacoviello L, Schünemann HJ.(PubMed)
(10) Manipulating antioxidant intake in asthma: a randomized controlled trial by Wood LG1, Garg ML, Smart JM, Scott HA, Barker D, Gibson PG.(PubMed)
(11) Association of serum carotenoids and tocopherols with atopic diseases in Japanese children and adolescents by Okuda M1, Bando N, Terao J, Sasaki S, Sugiyama S, Kunitsugu I, Hobara T.(PubMed)
(12) Carotenoid intake and asthma prevalence in Thai children by Rerksuppaphol S1, Rerksuppaphol L.(PubMed)
(13) Vitamin A deficiency decreases and high dietary vitamin A increases disease severity in the mouse model of asthma by Schuster GU1, Kenyon NJ, Stephensen CB.(PubMed)
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