Vitexin is an apigenin flavone glucoside occurring in passionflower, chaste tree, bamboo leaves, pearl1 millet, mung bean, hawthorn, fenugreek2 and other plants.
A related compound, isovitexin, is also found in passionflower and mung bean, as well as in açaí, cannabis, buckwheat and wild green oat.
Over the past couple of decades, research has been dominated by studies that have identified the compounds in a number of plants, and investigations into their health benefits has only recently commenced in earnest.
”Vitexin and isovitexin are active components of many traditional Chinese medicines and were found in various medicinal plants,” write M. He and colleagues in a 2016 review. “Vitexin (apigenin-8-C-glucoside) has recently received increased attention due to its wide range of pharmacological effects, including but not limited to antioxidant, anticancer, anti-inflammatory, antihyperalgesic, and neuroprotective effects. Isovitexin (apigenin-6-C-glucoside), an isomer of vitexin, generally purified together with vitexin, also exhibits diverse biological activities.”3
Vitexin and isovitexin have powerful antioxidant properties.4 Research in cultured human skin fibroblasts has revealed a strong ability for vitexin to scavenge free radicals generated by exposure to ultraviolet B radiation.5 This suggests a potential use for vitexin in the prevention of skin damage caused by sun exposure.
2. Protection from Viral and Bacterial Invaders
Vitexin has shown an antiviral action against parainfluenza type 3 and rotavirus.6,7 Vitexin and isovitexin were identified in one study as compounds having an effect against Helicobacter pylori, the bacterium that is the primary cause of gastric ulcers.4 Recent research indicates that vitexin may have an inhibitory effect against bacterial biofilm formation.8
3. Inflammation Management
In an experiment with mice, vitexin was shown to inhibit inflammatory pain.9 It was determined that vitexin prevented a decrease in the animals’ ability to scavenge free radicals and inhibited the production of inflammatory cytokines. Other research conducted on mice found that vitexin relieved pain via mechanisms utilized by opioids.10
In research involving rat tumor cells, vitexin inhibited migration and invasion.11 In human oral cancer cells, vitexin reduced cell viability while decreasing metastasis.12 Vitexin has also shown effects against human breast cancer and leukemia cells.13
Research has shown that vitexin and isovitexin inhibit alpha-glucosidase (an enzyme that breaks down carbohydrates), suggesting a protective action against type 2 diabetes.14 In pancreatic beta cells exposed to an inflammation-inducing compound, vitexin significantly decreased apoptosis and levels of proinflammatory cytokines including tumor necrosis factor-alpha.15 “The present study provided clear evidence indicating that vitexin may be a viable therapeutic strategy for the treatment of diabetes mellitus,” authors F. Wang and colleagues concluded.
6. Heart Health
In isolated rat hearts subjected to ischemia and reperfusion, vitexin enhanced coronary artery blood flow and improved heart muscle pathological scores.16 In rats in which hypertension was induced, an aqueous extract of Colocasia esculenta Linn showed ACE inhibitory, vasodilatory, beta-blocking and/or calcium channel blocking actions thereby lowering blood pressure and providing a diuretic effect.17 These effects were attributed to vitexin, isovitexin and other components present in the plant’s leaves.
7. Antiaging and Cognition
In a mouse model of aging induced by the injection of D-galactose for eight weeks, vitexin improved the animals’ general medical status, increased brain weight, and elevated total antioxidant capacity and the endogenous enzymes superoxide dismutase, catalase, and glutathione peroxidase in brain, kidneys, and liver in comparison with untreated aged mice.18
Vitexin also improved neuronal ultrastructure and lowered levels of malondialdehyde, a marker of lipid peroxidation. A 40 mg per kilogram dose of vitexin was associated with the same antioxidant capacity as vitamin E. Activity and appearance, and hair color and luster all improved in aged mice that received vitexin. “Vitexin can delay aging by maintaining normal cell structures, reducing the aging of brain nerve cells, and thus allowing them to function normally, which could be the mechanism for its anti-aging effects,” Fang An and colleagues concluded.
Further evidence that vitexin could benefit the brain was revealed by a study in rats which found a potential role for vitexin in the enhancement of memory retrieval.19 In cultured cortical neurons in which potentially damaging excitotoxicity was induced by the compound NMDA, pretreatment with vitexin prevented cell loss and reduced the amount of neurons that underwent apoptosis.20 And in mice subjected to ischemia/reperfusion injury, treatment with vitexin decreased neurologic deficits, cerebral infarct volume, and neuronal damage in comparison with mice that also underwent ischemia/reperfusion but did not receive vitexin.21 Other studies indicated a protective effect for vitexin against amyloid beta peptide-induced toxicity and neurotoxicity induced by exposure to the general anesthetic isoflurane.22, 23
As suggested by previous research, the antiaging effect of vitexin could extend lifespan. When tested in the roundworm C. elegans, vitexin extended life and improved survival in stressful environments while not affecting offspring, food intake and growth.24 It also increased antioxidant enzymes and dose-dependently lowered intracellular reactive oxygen species. The improvement in body movement observed in aged worms treated with vitexin suggests that the compound favorably affects healthspan as well as longevity. “These results suggest that vitexin might be a probable candidate which could extend the human lifespan,” E. B. Lee and colleagues concluded.
As indicated by the evidence presented herein, research involving flavonoid C-glycosides such as vitexin and isovitexin is still in its preliminary stages. The number of promising studies reported suggests that we can look forward to further rewarding experimental research and, it is to be hoped, human trials.
“Flavonoid C-glycosides showed significant antioxidant activity, anticancer, and antitumor activity, hepatoprotective activity, anti-inflammatory activity, anti-diabetes activity, antiviral activity, antibacterial and antifungal activity, and other biological effects,” observed J. Xiao and colleagues in a 2016 review. “However, there is a lack of in vivo data on the biological benefits of flavonoid C-glycosides. It is necessary to investigate more on how flavonoid C-glycosides prevent and handle the diseases.”25