Bioflavonoids: Benefits, Dosage, Contraindications

Antioxidant

Citrus bioflavonoids, thanks to their exceptional antioxidant properties, play an important role in combating oxidative stress and cellular aging. These natural compounds act in multiple ways: they neutralize various free radicals such as hydroxyl and superoxide radicals, prevent lipid peroxidation, and chelate metals, thus preventing oxidation catalyzed by these metals. Their "free radical scavenger" activity is mainly due to their ability to donate hydrogen atoms through the phenolic groups they possess, allowing the stabilization of radicals on their molecular structure. Research shows that orange juices rich in flavonoids and other polyphenols offer significant antioxidant capacity, suggesting that daily intake of orange juice could provide additional protection against oxidation.

Anti-inflammatory

Citrus bioflavonoids, notably hesperidin and nobiletin, have demonstrated a notable capacity to modulate immune and inflammatory responses. Their anti-inflammatory effects can be attributed to the inhibition of key regulatory enzymes such as protein kinase C, phosphodiesterase, phospholipase, lipoxygenase, and cyclooxygenase, which play a crucial role in the formation of biological mediators activating endothelial and other specialized cells in inflammation. For instance, hesperidin can reduce inflammation in cases of pleurisy (a medical condition characterized by inflammation of the pleura, a thin membrane surrounding the lungs and lining the inner wall of the thoracic cavity), decreasing fluid and the number of involved white blood cells. Nobiletin, on the other hand, has shown selective action in down-regulating the expression of cyclooxygenase-2 without affecting cyclooxygenase-1, and has reduced the production of prostaglandin E2 and the expression of pro-inflammatory cytokines.

Vein Tonic

Bioflavonoids, including hesperidin, significantly improve venous health through several interdependent mechanisms that have been widely documented through clinical and experimental studies. These natural compounds mainly act by enhancing venous tone and reducing venous stasis, which is crucial for preventing and managing chronic venous insufficiency (CVI) symptoms. Hesperidin plays a vital role in modulating inflammation and protecting venous structures from damage. It inhibits the synthesis of prostaglandins and free radicals, reduces microvascular leaks induced by bradykinin (a vasodilator peptide that helps increase blood flow), and limits leukocyte activation and migration. These actions decrease leukocyte infiltration and tissue damage associated with CVI, facilitating the healing of venous ulcers and reducing edema. In clinical practice, the use of hesperidin has shown improvement in endothelial function, essential for maintaining the integrity of blood vessels and preventing vascular complications. Hesperidin supplementation could thus represent a promising therapeutic approach for treating venous insufficiency.

Usages associés

Anticancer

Citrus bioflavonoids, by their antimutagenic effects, significantly inhibit tumor development and cell proliferation. They protect DNA from damage caused by UV rays and neutralize free radicals that can induce mutations near DNA. Furthermore, flavonoids such as naringin and nobiletin have shown their ability to inhibit enzymes involved in tumor promotion and reduce the expression of certain pro-inflammatory genes, thereby limiting the development and progression of cancer cells. Studies have revealed that citrus flavonoids can delay tumor development, notably by positively influencing cell metabolism and inhibiting key metabolic pathways in tumor cells. They also exert a direct cytotoxic effect on various types of cancer cells, inducing apoptosis (programmed cell death) without affecting surrounding healthy cells.

Cardiovascular

Citrus flavonoids, including hesperidin, naringin, and nobiletin, have demonstrated a wide range of beneficial effects on cardiovascular and metabolic health, partly due to their powerful antioxidant activity, ability to improve glucose tolerance and insulin sensitivity, and modulatory effect on lipid metabolism and adipocyte differentiation. Additionally, they contribute to the suppression of inflammation and apoptosis and improve endothelial function, a critical factor in the prevention of cardiovascular diseases. Hesperidin, for instance, acts by inhibiting phosphodiesterase and increasing intracellular cAMP, resulting in a reduction in the production of inflammatory prostaglandins and thromboxane B2. This action is crucial for its anti-inflammatory effects and for reducing platelet aggregation, helping prevent thrombus formation. Preliminary clinical research has shown that daily intake of 500 mg of hesperidin increases flow-mediated dilation, indicating an improvement in endothelial function in patients with metabolic syndrome, in addition to reducing inflammatory biomarkers such as C-reactive protein.

Usages associés

Antimicrobial

Studies have shown that bioflavonoids possess significant antimicrobial activity, particularly against various viruses and bacteria. This activity is primarily due to non-glycosylated compounds, and the presence of a hydroxyl group at position 3 is essential for antiviral activity. 40-hydroxy-3-methoxy flavones have demonstrated efficacy against rhino and polio viruses. The structure of these flavonoids, especially multiple substitutions in the A-ring, is crucial for their superior antiviral activity. For example, quercetin and hesperidin inhibit the replication of several viruses, including herpes simplex and poliovirus. However, not all flavonoids exert this activity; naringenin from grapefruit, for instance, has not shown this efficacy.

Neurological

Bioflavonoids such as hesperidin demonstrate a notable neuroprotective potential, particularly relevant for neurodegenerative disorders like Parkinson's and Alzheimer's disease. Hesperidin protects against hydrogen peroxide-induced neurotoxicity in a laboratory model. It acts by attenuating behavioral alterations, oxidative stress, and mitochondrial enzyme complex dysfunctions, possibly through a mechanism related to nitric oxide. In the context of Parkinson's disease, hesperidin improves vascular tone and reduces stasis, contributing to the normalization of capillary permeability and lymphatic drainage, which is crucial for modulating inflammatory responses in the brain. It also inhibits phosphodiesterase, thus increasing intracellular cAMP, reducing the production of inflammatory prostaglandins and thromboxane, key molecules in inflammatory and coagulation processes associated with neurodegeneration. Moreover, hesperidin has shown positive effects on endothelial function, which is essential for preventing cardiovascular complications often associated with neurodegenerative diseases. It also helps modulate leukocyte gene expression, which could contribute to its anti-atherogenic and cardioprotective effects, thereby reducing the risks of progression of neurodegenerative diseases. By regulating Glutathione (GSH) levels, Glutathione Peroxidase (GPx) and Catalase activities, and preventing the formation of reactive oxygen species, hesperidin could help prevent the depletion of dopamine and its metabolites, essential in the context of diseases like Parkinson's.