Science & mechanisms

Photobiomodulation at the cellular level

How can 660 nm red light act on allergic rhinitis? The answer is cellular. Here are the precise biological mechanisms that explain the effects of photobiomodulation.

Definition

What is photobiomodulation?

Photobiomodulation (PBM) is a technique that uses gentle light, typically red or near-infrared, to trigger precise biological mechanisms within cells. Unlike surgical lasers that destroy tissue with heat, PBM acts at non-thermal intensities: it stimulates without burning, activates without aggressing.

The technology relies on low-level lasers or LED diodes emitting at specific wavelengths, generally between 630 and 850 nm. These photons pass through tissue and are absorbed by target molecules within cells, triggering a cascade of beneficial biological reactions.

Applied to the nasal passages at 660 nm, it directly targets the nasal mucosa, the site of inflammatory reactions associated with allergic rhinitis and sinusitis.

Mechanism of action

From light to cell: how it works

01

Absorption by chromophores

660 nm photons penetrate nasal tissue and are absorbed by specific molecules called chromophores. The main chromophore is cytochrome c oxidase, a key enzyme in the mitochondrial respiratory chain.

02

Mitochondrial activation

Light absorption by cytochrome c oxidase stimulates the electron transport chain in mitochondria. This process increases the mitochondrial membrane potential and accelerates cellular energy production.

03

Increased ATP synthesis

Stimulation of the respiratory chain results in increased production of ATP (adenosine triphosphate), the universal fuel for cells. Cells then have more energy to perform their repair and regulatory functions.

The central role

Mitochondria: the cell's power plants

Mitochondria are the organelles responsible for producing ATP, the essential fuel for all cellular functions. Under normal conditions, they operate at a given activity level determined by the cell's metabolic needs.

During inflammation, as in the case of allergic rhinitis, nasal mucosa cells are subjected to significant oxidative stress. This stress impairs mitochondrial function and reduces ATP production, weakening the mucosa's natural defence mechanisms.

660 nm red light acts directly on cytochrome c oxidase, enabling mitochondria to return to optimal activity and produce the energy needed to regulate inflammation.

+ATP
Increased cellular energy production
ROS
Regulation of oxidative free radicals
NO
Release of vasodilatory nitric oxide
CCO
Activation of cytochrome c oxidase
Biological cascade

The four key biological effects

The increase in ATP production triggers a cascade of beneficial reactions in the cells of the nasal mucosa.

Inflammation modulation

Reduction of pro-inflammatory mediators

Photobiomodulation regulates pro-inflammatory signals (cytokines, prostaglandins) produced by mast cells and eosinophils during an allergic reaction. By rebalancing these signals, it helps reduce congestion, sneezing, and nasal itching.

Oxidative stress regulation

Rebalancing the oxidant/antioxidant balance

Free radicals (ROS, reactive oxygen species) play a role in chronic inflammation of the nasal passages. PBM restores the balance between free radical production and the cells' antioxidant capacity, creating a more stable cellular environment without eliminating these necessary phenomena.

Release of nitric oxide (NO)

Improved nasal microcirculation

Light stimulation promotes the release of nitric oxide from cytochrome c oxidase. This vasodilator improves microcirculation in the nasal mucosa, promotes tissue oxygenation, and participates in local immune regulation.

Improved cellular communication

Optimised immune and epithelial coordination

Better ATP availability supports communication between immune, epithelial and nerve cells. This reinforced cellular coordination contributes to a more balanced immune response and better mucosa resilience in the face of allergens.

Technical parameters

What determines treatment effectiveness

The results of photobiomodulation depend directly on the precision of the parameters used. Each variable influences penetration depth and cellular response.

WavelengthCritical
660 nm

The optical window between 630 and 700 nm is optimal for the nasal mucosa. At 660 nm, tissue penetration is maximal and absorption by cytochrome c oxidase is at its peak.

Power densityCalibrated
30–100 mW/cm²

Light intensity must remain within the therapeutic window. Too low: no biological effect. Too high: thermal risk. Rubience is calibrated in the optimal range.

Session durationValidated
10 minutes

Duration validated by clinical studies to deliver a sufficient light dose (6 J/cm²) while remaining comfortable. Auto-shutoff ensures reproducibility.

FrequencyRecommended
1 session/day

Regularity is more important than intensity. A daily 10-minute session enables continuous stimulation of regulation mechanisms without over-exciting cells.

Penetration depthOptimal
2–5 mm

At 660 nm, light penetrates the nasal mucosa (1–3 mm thick) sufficiently to reach epithelial cells, mast cells, and submucosal immune cells.

Time to effectProgressive
2–4 weeks

Biological effects accumulate progressively. First improvements appear from the first week, but significant effects are measurable after 2 to 4 weeks of regular use.

Application for rhinitis & sinusitis

Why red light works on the nasal mucosa

The nasal mucosa is particularly receptive to photobiomodulation for several reasons. First, accessibility: the nostrils allow the light tips to be inserted directly in contact with the mucosa, without the light needing to pass through thick layers of tissue.

Second, the cellular composition of the inflamed nasal mucosa: it is densely populated with mast cells, eosinophils and T lymphocytes, all involved in the allergic cascade and all equipped with mitochondria sensitive to red light.

During allergic rhinitis, exposure to an allergen triggers mast cell degranulation, releasing histamine, leukotrienes and pro-inflammatory cytokines. Photobiomodulation at 660 nm intervenes upstream of this cascade by stabilising mast cells and reducing their reactivity to allergens.

For sinusitis, the anti-inflammatory effects and stimulation of microcirculation help reduce mucosal oedema and improve sinus drainage.

Cellular targets in the nasal mucosa

Mast cells
Stabilisation, reduced degranulation
Less histamine released
Eosinophils
Modulation of activation
Reduced tissue inflammation
Epithelial cells
Strengthening the mucosal barrier
Better resistance to allergens
Endothelial cells
Regulation of vascular permeability
Reduced oedema
Macrophages
Modulation of immune response
Anti-inflammatory phenotype favoured

Important: The results of photobiomodulation vary according to initial cellular state, session frequency, technical parameters used and overall environment. Photobiomodulation is a complementary treatment: it does not replace medical treatment prescribed by a healthcare professional.

Evolving responses

Why effects are progressive

Photobiomodulation does not act like an antihistamine drug that chemically blocks a reaction. Its mode of action is fundamentally different: it supports and optimises the natural biological mechanisms of cells.

As such, effects accumulate progressively. Each session contributes to rebalancing the cellular environment of the nasal mucosa. The most significant benefits are observed after several weeks of regular use, once cells have had time to reconfigure towards a state less reactive to allergens.

Studies have documented benefits persisting for several months after stopping treatment, suggesting that PBM induces lasting changes in the nasal mucosa microenvironment rather than a simple transient symptomatic effect.

Rubience

Nasal photobiomodulation, now accessible at home

Rubience integrates these mechanisms into a compact, calibrated device for daily use. 660 nm red light, 10-minute auto-shutoff, medical-grade silicone tips.