Vitamin C Is an Essential Factor on the Anti-viral Immune Responses through the Production of Interferon-α/β at the Initial Stage of Influenza A Virus (H3N2) Infection.
Level 5 - mechanism / opinion, no new human data
Animal research using knockout mice without human data
PubMed 23700397 · doi:10.4110/in.2013.13.2.70
What was done
Researchers infected vitamin C-deficient Gulo (-/-) mice (a genetic knockout model unable to synthesize vitamin C, mimicking human physiology) intranasally with influenza A virus (H3N2/Hongkong). They evaluated survival, lung viral titers, antiviral cytokine production (interferon-alpha/beta), pulmonary inflammatory cell infiltration, and proinflammatory cytokine levels (TNF-alpha and IL-1alpha/beta).
What was found
The abstract reports directional findings without numerical values or exact statistics. Vitamin C-insufficient mice died within 1 week of infection. In these mice, lung viral titers were increased, interferon (IFN)-alpha/beta production was decreased, and lung inflammatory cell infiltration and proinflammatory cytokines (TNF-alpha and IL-1alpha/beta) were increased compared to vitamin C-sufficient controls.
Why it matters
This study provides mechanistic evidence in a mammalian model that basal vitamin C is necessary for early type I interferon antiviral responses and for limiting pulmonary inflammatory pathology during influenza A infection.
Limits
This is an animal study using knockout mice; results cannot be directly generalized to human clinical outcomes or supplement dosing. The abstract does not report sample sizes (n), quantitative measurements, variance, or statistical significance thresholds.
Cited by
- supports Vitamin C is involved in the production of interferon cytokines in mice.
- supports In a vitamin C-deficient mouse model of viral infection, deficient mice had a 10- to 15-fold increase in lung viral titers and 100% mortality after one week, while 100% of normal mice survived.
- supports Supplementing vitamin C-deficient mice with vitamin C prior to viral infection achieved plasma levels of 80 to 100 micromolar, prevented increased lung viral titers, increased antiviral cytokines, and protected against death.