2,869
edits
Quercetin: Difference between revisions
no edit summary
No edit summary |
|||
| (14 intermediate revisions by the same user not shown) | |||
| Line 1: | Line 1: | ||
'''Quercetin''' is a naturally occurring flavonoid found in a wide variety of fruits, vegetables, and grains. It is one of the most abundant antioxidants in the human diet and plays a significant role in helping to protect cells from damage caused by free radicals. | [[File:Quercetin.svg|right|frameless]] | ||
'''Quercetin''' is a naturally occurring flavonoid found in a wide variety of fruits, vegetables, and grains. It is one of the most abundant [[Antioxidant|antioxidants]] in the human diet and plays a significant role in helping to protect cells from damage caused by free radicals. | |||
Quercetin belongs to the class of polyphenolic compounds known as flavonoids, recognized for their diverse biological activities. It is a pigment that is responsible, in part, for the colors of many fruits, vegetables, and flowers. Structurally, quercetin is characterized by the presence of a 15-carbon skeleton consisting of two phenyl rings and a heterocyclic ring. | Quercetin belongs to the class of polyphenolic compounds known as flavonoids, recognized for their diverse biological activities. It is a pigment that is responsible, in part, for the colors of many fruits, vegetables, and flowers. Structurally, quercetin is characterized by the presence of a 15-carbon skeleton consisting of two phenyl rings and a heterocyclic ring. | ||
| Line 5: | Line 6: | ||
The term "quercetin" is derived from ''quercetum'' (oak forest), reflecting its presence in oak trees. It was first isolated in 1857 by the Austrian chemist Heinrich Hlasiwetz. Since its discovery, quercetin has been the subject of extensive research, with numerous studies exploring its potential health benefits, primarily due to its antioxidant, anti-inflammatory, antiviral, and anticancer properties. | The term "quercetin" is derived from ''quercetum'' (oak forest), reflecting its presence in oak trees. It was first isolated in 1857 by the Austrian chemist Heinrich Hlasiwetz. Since its discovery, quercetin has been the subject of extensive research, with numerous studies exploring its potential health benefits, primarily due to its antioxidant, anti-inflammatory, antiviral, and anticancer properties. | ||
In plants, quercetin serves as a protective substance, defending against microbial infections and environmental stress. For humans, it’s predominantly obtained through the consumption of foods such as onions, apples, berries, and teas. Its biological roles in human health are vast, with studies suggesting benefits ranging from anti-aging and anti-inflammatory effects to potential protective roles against various diseases. | In plants, quercetin serves as a protective substance, defending against microbial infections and environmental stress. This feature positions quercetin as a [[Xenohormetic Compound|xenohormetic compound]], implying that it not only protects the plants producing it but also potentially offers health benefits to humans who consume these plants. For humans, it’s predominantly obtained through the consumption of foods such as onions, apples, berries, and teas. Its biological roles in human health are vast, with studies suggesting benefits ranging from anti-aging and anti-inflammatory effects to potential protective roles against various diseases. | ||
== Natural Occurrence and Derivatives== | == Natural Occurrence and Derivatives== | ||
| Line 77: | Line 78: | ||
|} | |} | ||
In red onions, higher concentrations of quercetin occur in the outermost rings and in the part closest to the root, the latter being the part of the plant with the highest concentration. | In red onions, higher concentrations of quercetin occur in the outermost rings and in the part closest to the root, the latter being the part of the plant with the highest concentration.{{#pmid:17997520|pmid17997520}} One study found that [[wikipedia:Organic_farming|organically grown]] [[wikipedia:Tomato|tomatoes]] had 79% more quercetin than non-organically grown fruit.{{#pmid:17590007|pmid17590007}} Quercetin is present in various kinds of [[wikipedia:Honey|honey]] from different plant sources. {{#pmid:21229237|pmid21229237}} | ||
=== Background Intake === | === Background Intake === | ||
| Line 159: | Line 160: | ||
Quercetin's bioavailability is complex, influenced largely by its poor water solubility, which results in low absorption and extensive metabolism, hence reducing its availability to exert biological effects. It is predominantly found in foods as glycosides, bound to sugar molecules, which impacts its absorption and subsequent bioavailability. | Quercetin's bioavailability is complex, influenced largely by its poor water solubility, which results in low absorption and extensive metabolism, hence reducing its availability to exert biological effects. It is predominantly found in foods as glycosides, bound to sugar molecules, which impacts its absorption and subsequent bioavailability. | ||
In a clinical study with a different formulation of quercetin (Quercetin Phytosome) a ~20 fold relative bioavailability compared to standard quercetin was measured. Given that Quercetin Phytosome contains ~40% quercetin, one can assume that the total bioavailability of standard quercetin is less than 2%. | In a clinical study with a different formulation of quercetin (Quercetin Phytosome) a ~20 fold relative bioavailability compared to standard quercetin was measured. Given that Quercetin Phytosome contains ~40% quercetin, one can assume that the total bioavailability of standard quercetin is less than 2%. {{#pmid:30328058|pmid30328058}} | ||
Quercetin, when consumed, undergoes an absorption process primarily in the small intestine. The glycosidic form of quercetin needs to be hydrolyzed by β-glucosidase to its aglycone form before absorption. Once hydrolyzed, it is absorbed through enterocytes via passive diffusion or through active transport mechanisms. The overall absorption of quercetin is estimated to be relatively low, varying between individuals and dependent on dietary matrix and presence of other flavonoids. | Quercetin, when consumed, undergoes an absorption process primarily in the small intestine. The glycosidic form of quercetin needs to be hydrolyzed by β-glucosidase to its aglycone form before absorption. Once hydrolyzed, it is absorbed through enterocytes via passive diffusion or through active transport mechanisms. The overall absorption of quercetin is estimated to be relatively low, varying between individuals and dependent on dietary matrix and presence of other flavonoids. | ||
Once absorbed, quercetin undergoes extensive first-pass metabolism in the liver and intestines, where it is converted into various metabolites through glucuronidation, sulfation, and methylation. The extensive metabolism significantly reduces the concentrations of free quercetin in the plasma, limiting its bioavailability. The metabolites, however, may retain some biological activity and contribute to the overall effects of quercetin in the body. | Once absorbed, quercetin undergoes extensive first-pass metabolism in the liver and intestines, where it is converted into various metabolites through glucuronidation, sulfation, and methylation. The extensive metabolism significantly reduces the concentrations of free quercetin in the plasma, limiting its bioavailability. The metabolites, however, may retain some biological activity and contribute to the overall effects of quercetin in the body. | ||
It is suggested that individuals with poor vitamin C status might absorb quercetin better than those with adequate vitamin C levels. This could indicate a compensatory mechanism where the body might try to absorb more of certain beneficial compounds, like quercetin, in the absence of others, like vitamin C. However, the exact mechanisms or reasons behind this would need to be further explored. {{#pmid:25280405|pmid25280405}} | |||
===Formulation of Enhanced Bioavailability=== | ===Formulation of Enhanced Bioavailability=== | ||
| Line 197: | Line 200: | ||
===Quercetin Phytosome=== | ===Quercetin Phytosome=== | ||
[[File:Pharmacokinetic profile of quercetin.png|thumb|[[Pharmacokinetic]] profile of standard quercetin and quercetin phytosome in the clinical study. The plasma concentrations of quercetin obtained after single oral administration of the unformulated quercetin at 500 mg/tablet and after single oral administration of its corresponding lecithin formulation, Quercetin Phytosome, at a dose of either 500 or 250 mg are shown. | [[File:Pharmacokinetic profile of quercetin.png|thumb|[[Pharmacokinetic]] profile of standard quercetin and quercetin phytosome in the clinical study. The plasma concentrations of quercetin obtained after single oral administration of the unformulated quercetin at 500 mg/tablet and after single oral administration of its corresponding lecithin formulation, Quercetin Phytosome, at a dose of either 500 or 250 mg are shown. {{#pmid:30328058|pmid30328058}}]] | ||
Quercetin Phytosome is a formulation where quercetin is bound to phospholipids, typically derived from sunflower or soy lecithin, to enhance its bioavailability and absorption. The relevant clinical study used Quercetin Phytosome (QUERCEFIT™) consisting of quercetin and sunflower lecithin in a 1:1 weight ratio along with about a fifth part of food-grade excipients that are added to improve the physical state of the product and to standardize it to an HPLC-measured total quercetin content of about 40%. In the clinical study, a ~20-fold increase in bioavailability was measured compared to standard quercetin with equal doses. | Quercetin Phytosome is a formulation where quercetin is bound to phospholipids, typically derived from sunflower or soy lecithin, to enhance its bioavailability and absorption. The relevant clinical study used Quercetin Phytosome (QUERCEFIT™) consisting of quercetin and sunflower lecithin in a 1:1 weight ratio along with about a fifth part of food-grade excipients that are added to improve the physical state of the product and to standardize it to an HPLC-measured total quercetin content of about 40%. In the clinical study, a ~20-fold increase in bioavailability was measured compared to standard quercetin with equal doses. {{#pmid:30328058|pmid30328058}} | ||
{| class="wikitable" | {| class="wikitable" | ||
|+[[Pharmacokinetic]] parameters (noncompartmental model) | |+[[Pharmacokinetic]] parameters (noncompartmental model) {{#pmid:30328058|pmid30328058}} | ||
! | ! | ||
!Quercetin 500 mg | !Quercetin 500 mg | ||
| Line 240: | Line 243: | ||
In a study sponsored by Natural Factors, the bioavailability of Standard Quercetin, Quercetin Phytosome and Quercetin LipoMicel was evaluated. The results indicated that Quercetin LipoMicel had a relative bioavailability to Standard Quercetin of 8.5, while Quercetin Phytosome exhibited a slightly higher value of 8.9. Notably, LipoMicel maintained more consistent levels of quercetin in the system over a 24-hour period. <ref name=":1">https://jnhpresearch.com/index.php/jnhpr/article/view/17/24</ref> | In a study sponsored by Natural Factors, the bioavailability of Standard Quercetin, Quercetin Phytosome and Quercetin LipoMicel was evaluated. The results indicated that Quercetin LipoMicel had a relative bioavailability to Standard Quercetin of 8.5, while Quercetin Phytosome exhibited a slightly higher value of 8.9. Notably, LipoMicel maintained more consistent levels of quercetin in the system over a 24-hour period. <ref name=":1">https://jnhpresearch.com/index.php/jnhpr/article/view/17/24</ref> | ||
In a second study, the blood concentrations of quercetin in healthy participants after the administration of standard quercetin and LipeMice quercetin was evaluated with over 72 hours and 4 doses in total. Within the first 24 hours, LipeMice (500mg) had a significantly 7-fold increased blood concentrations of quercetin compared to standard quercetin (500 mg). LipeMice administered at a double dose (1000 mg) achieved 15-fold higher absorption, LipeMice tested at half a dose of standard quercetin increased concentration by approx. 3-fold. Quercetin blood concentrations were attained over 72 hours. | In a second study, the blood concentrations of quercetin in healthy participants after the administration of standard quercetin and LipeMice quercetin was evaluated with over 72 hours and 4 doses in total. In contrast to other studies, the administration was given after 10 hours of fasting and continued fasting for 4 hours afterward to reduce potential interactions with food components like fiber and fat. Within the first 24 hours, LipeMice (500mg) had a significantly 7-fold increased blood concentrations of quercetin compared to standard quercetin (500 mg). LipeMice administered at a double dose (1000 mg) achieved 15-fold higher absorption, LipeMice tested at half a dose of standard quercetin increased concentration by approx. 3-fold. Quercetin blood concentrations were attained over 72 hours. {{#pmid:37600550|pmid37600550}} | ||
{| class="wikitable" | {| class="wikitable" | ||
|+[[Pharmacokinetic]] | |+[[Pharmacokinetic]] Parameters of Quercetin | ||
! | ! | ||
! colspan="3" |Study 1 <ref name=":1" /> | ! colspan="3" |Study 1 <ref name=":1" /> | ||
! colspan="4" |Study 2 | ! colspan="4" |Study 2 (with fasting) {{#pmid:37600550|pmid37600550}} | ||
|- | |- | ||
! | ! | ||
! | !Standard | ||
500mg | 500mg | ||
! | !LipoMicel | ||
500mg | 500mg | ||
! | !Phytosome | ||
500mg | 500mg | ||
! | !Standard | ||
500mg | 500mg | ||
! | !LipoMicel | ||
250mg | 250mg | ||
! | !LipoMicel | ||
500mg | 500mg | ||
! | !LipoMicel | ||
1000mg | 1000mg | ||
|- | |- | ||
| Line 268: | Line 271: | ||
| 1477.27 ± 25.57 | | 1477.27 ± 25.57 | ||
| 1536.00 ± 115.66 | | 1536.00 ± 115.66 | ||
|77.3 | |77.3 ± 6.1 | ||
| | |197.0 ± 8.0 | ||
| | |543.1 ± 20.3 | ||
| | |1128.8 ± 52.3 | ||
|- | |- | ||
| colspan="1" rowspan="1" |[[Cmax|C<sub>max</sub>]] (ng/ml) | | colspan="1" rowspan="1" |[[Cmax|C<sub>max</sub>]] (ng/ml) | ||
| Line 277: | Line 280: | ||
| 182.85 ± 106.64 | | 182.85 ± 106.64 | ||
| 150.27 ± 61.43 | | 150.27 ± 61.43 | ||
| | |6.8 ± 9.2 | ||
| | |15.4 ± 22.0 | ||
| | |52.5 ± 51.7 | ||
| | |150.4 ± 117.6 | ||
|- | |- | ||
| colspan="1" rowspan="1" |[[Time to Maximum Concentration (Tmax)|T<sub>max</sub>]] (hours) | | colspan="1" rowspan="1" |[[Time to Maximum Concentration (Tmax)|T<sub>max</sub>]] (hours) | ||
| Line 286: | Line 289: | ||
| 0.5 ± 0.02 | | 0.5 ± 0.02 | ||
| 1 ± 0.30 | | 1 ± 0.30 | ||
| | |3.0 ± 3.2 | ||
| | |1.0 ± 2.7 | ||
| | |5.9 ± 2.7 | ||
| | |0.9 ± 0.2 | ||
|- | |- | ||
| colspan="1" rowspan="1" |[[Elimination Half-Life|''t''<sub>1/2</sub>]] (hours) | | colspan="1" rowspan="1" |[[Elimination Half-Life|''t''<sub>1/2</sub>]] (hours) | ||
| Line 308: | Line 311: | ||
: Quercetin’s potent anti-inflammatory properties have led to its investigation for use in chronic inflammatory conditions such as arthritis and cardiovascular diseases. It modulates inflammatory pathways by inhibiting the release of pro-inflammatory cytokines and reducing the activation of inflammatory cells. | : Quercetin’s potent anti-inflammatory properties have led to its investigation for use in chronic inflammatory conditions such as arthritis and cardiovascular diseases. It modulates inflammatory pathways by inhibiting the release of pro-inflammatory cytokines and reducing the activation of inflammatory cells. | ||
; Antioxidant Properties | ; [[Antioxidant]] Properties | ||
: The antioxidant activity of quercetin is attributed to its ability to neutralize free radicals and reduce oxidative stress, potentially mitigating aging-related cellular damage and dysfunction. Its antioxidant properties are linked to a reduction in the risk of chronic conditions such as cancer and neurodegenerative diseases. | : The antioxidant activity of quercetin is attributed to its ability to neutralize free radicals and reduce oxidative stress, potentially mitigating aging-related cellular damage and dysfunction. Its antioxidant properties are linked to a reduction in the risk of chronic conditions such as cancer and neurodegenerative diseases. | ||
; Impact on Cellular Senescence | ; Impact on [[Cellular Senescence]] | ||
: Research has indicated that quercetin may delay cellular senescence by modulating senescence-associated signaling pathways and reducing the accumulation of senescent cells, potentially impacting aging processes and age-related diseases. | : Research has indicated that quercetin may delay cellular senescence by modulating senescence-associated signaling pathways and reducing the accumulation of senescent cells, potentially impacting aging processes and age-related diseases. | ||
| Line 328: | Line 331: | ||
===Administration Forms and Bioavailability Enhancement=== | ===Administration Forms and Bioavailability Enhancement=== | ||
Quercetin is available in various forms, including tablets, capsules, and powders. To enhance its bioavailability, it is often formulated with bioflavonoids or bromelain, or encapsulated in liposomes or phytosomes. Different formulations may affect the absorption and efficacy of quercetin, and choosing the right form is crucial for optimal results. | Quercetin is available in various forms, including tablets, capsules, and powders. To enhance its bioavailability, it is often formulated with bioflavonoids or bromelain, or encapsulated in [[Liposomes|liposomes]] or phytosomes. Different formulations may affect the absorption and efficacy of quercetin, and choosing the right form is crucial for optimal results. | ||
==Safety and Side Effects== | ==Safety and Side Effects== | ||
| Line 347: | Line 350: | ||
==Conclusions and Future Directions== | ==Conclusions and Future Directions== | ||
'''Quercetin''' has garnered substantial attention in the realm of longevity and health due to its multifaceted biological activities, including antioxidant, anti-inflammatory, and potential anti-aging properties. | '''Quercetin''' has garnered substantial attention in the realm of longevity and health due to its multifaceted biological activities, including [[Antioxidant|antioxidant]], anti-inflammatory, and potential anti-aging properties. | ||
=== Summary of Key Findings=== | === Summary of Key Findings=== | ||
| Line 362: | Line 365: | ||
== See Also == | == See Also == | ||
* | * {{SeeWikipedia|Quercetin}} | ||
== References == | == References == | ||
<references /> | <references /> | ||
[[Category:Orally Consumable Longevity | [[Category:Orally Consumable Longevity Compounds]] | ||
[[Category:Xenohormetic Compounds]] | |||
[[Category:Senolytic Compounds]] | |||
[[Category:Antioxidant Compounds]] | |||