Since ancient times, humans have been using plant resources to treat various diseases. With the development of modern medicine today, natural products and their improved derivatives are still one of the important sources for the development of new drugs. Among them, flavonoids, a type of polyphenolic compounds widely found in the plant kingdom, have attracted much attention due to their rich biological activities.
Among them, quercetin is undoubtedly one of the most famous flavonoids. This natural polyphenol compound is widely found in various fruits, vegetables and herbs and has demonstrated significant biological activities in wound healing, neuroprotection and anti-aging. However, quercetin has poor water solubility, which limits its clinical application to a certain extent. To this end, scientific researchers have been working hard to improve the solubility and stability of quercetin and its analogs through chemical modification, in order to further unleash its therapeutic potential in tissue repair and other fields.
Biological properties of quercetin
Quercetin is a flavonoid polyphenol compound that is widely found in various fruits, vegetables and herbs, such as onions, apples, grapes and tea. As a powerful antioxidant, quercetin scavenges free radicals and protects cells from oxidative stress. In addition, it can also regulate the regenerative response of cells by activating sirtuin proteins, playing an important role in wound healing, neuroprotection and anti-aging.
However, quercetin has poor water solubility, which limits its bioavailability and clinical application to a certain extent. To this end, scientific researchers have been exploring various methods to improve the solubility and stability of quercetin and its analogs, in order to expand their application prospects in the therapeutic field.
Quercetin application in tissue repair
Quercetin and its derivatives have shown good promise in wound healing, anti-fibrosis and treatment of ophthalmic diseases.
Wound healing
Studies have found that topical application of quercetin can effectively reduce scarring of corneas and skin wounds. Animal experiments show that quercetin can promote the healing of diabetic wounds and prevent the formation of scar tissue after corneal trauma. This is mainly due to the antioxidant and anti-inflammatory properties of quercetin, which can regulate cell metabolism and inhibit the occurrence of fibrosis.
Anti-fibrosis
Quercetin acts as a metabolic regulator at the cellular and tissue levels. It can inhibit the occurrence of fibrosis by reducing the production of lactic acid and regulating redox components. This lays the foundation for the application of quercetin in the treatment of fibrosis-related diseases such as skin scars, pulmonary fibrosis, and liver cirrhosis.
Eye diseases
The antioxidant properties of quercetin show its potential in preventing diabetes-related cataracts. Topical application of quercetin can also reduce ocular inflammation and levels of pro-inflammatory cytokines, helping to maintain ocular surface health. Animal experiment results show that quercetin can increase tear secretion, improve dry eye symptoms, and reduce the release of inflammatory factors. These findings lay the foundation for the application of quercetin in the treatment of various eye diseases.
Improve bioavailability
Although quercetin shows good promise in tissue repair, its oral bioavailability is low, which limits its clinical application to a certain extent. To this end, scientific researchers have been exploring various methods to improve the solubility and stability of quercetin and its analogs.
A common strategy is to introduce flexible amino-containing functional groups into the quercetin molecule. These amino functional groups can form salt compounds, which help to improve the solubility in water-soluble systems, and may also enhance the binding affinity to the pharmacological target, thereby improving the efficacy. In addition, depending on the chemical nature of the functional groups, these modifications may also increase the lipophilicity of the compounds, thereby improving the permeability of biological membranes.
For example, researchers have synthesized a quercetin analog containing a tertiary amine group. Its water solubility in the hydrochloride form exceeds 1 mg/mL, and its activity in inhibiting the proliferation of leukemia cells is improved compared with natural quercetin. More than 25 times. In addition, this compound can also induce apoptosis in a dose-dependent manner, and its mechanism of action may involve inhibiting the AKT signaling pathway.
Another example is that researchers synthesized a chrysin derivative that introduced a tertiary amine group at the C7 position. The C5 hydroxyl and C4 ketone groups of this compound may play a copper chelating effect, which is considered to be the key to its antioxidant and Aβ1-42 aggregation-inhibiting activity.
Through these chemical transformation methods, researchers have successfully improved the solubility and stability of quercetin analogues, laying the foundation for their clinical application in tissue repair and other fields.
Mechanism
The mechanism of action of quercetin and its derivatives in promoting tissue repair mainly includes the following aspects:
- Antioxidant activity: Quercetin is a powerful free radical scavenger that can protect cells from oxidative stress, thereby reducing inflammatory responses and inhibiting the fibrosis process.
- Anti-inflammatory effect: Quercetin can regulate the release of cytokines, inhibit the occurrence of inflammatory reactions, and is beneficial to wound healing and tissue repair.
- Metabolic regulation: Quercetin acts as a metabolic regulator at the cellular and tissue levels, inhibiting fibrosis by regulating redox status and lactate metabolism.
- Promote regeneration: Quercetin can activate sirtuin protein, regulate cell regeneration response, and play an important role in wound healing and tissue repair.
- Anti-fibrosis: Quercetin can inhibit the activation of myofibroblasts and collagen deposition, reduce the formation of scar tissue, and shows good prospects in the prevention and treatment of fibrosis-related diseases.
- Regulate cell signaling: Quercetin can exert its biological functions by regulating key intracellular signaling pathways (such as AMPK, Nrf2, etc.), thereby promoting tissue repair.
Quercetin and its derivatives have shown broad application prospects in wound healing, anti-fibrosis and treatment of ophthalmic diseases due to their diverse biological activities.
Outlook
Although quercetin and its analogs have shown good therapeutic potential in the field of tissue repair, further research is still needed to achieve successful clinical translation.
First, the precise mechanisms of action of these compounds need to be explored in depth. Through cell and animal experiments, we further elucidate their specific action processes in regulating cell signaling pathways, inhibiting inflammatory responses, and promoting tissue regeneration, laying the foundation for optimizing molecular structures and improving efficacy.
Secondly, it is necessary to further optimize the administration method and dosage form design of quercetin and its analogs. At present, most research focuses on local administration, while the pharmacokinetic properties of systemic administration still need to be studied in depth. By optimizing the administration route and dosage form, the enrichment and residence time of these compounds in target organs can be improved, thereby enhancing their therapeutic effect.
In addition, more preclinical and clinical trials are needed to evaluate the safety and effectiveness of these compounds in humans. Although quercetin has been deemed "Generally Recognized as Safe" (GRAS) by the US FDA as a dietary supplement, a large amount of preclinical research and clinical trial data are still needed to obtain approval for any therapeutic use.
In general, quercetin and its derivatives, as a class of natural products with diverse biological activities, have shown broad application prospects in the field of tissue repair. Through continuous research and innovation and further optimization of their delivery methods and dosage form design, it is believed that these compounds will eventually become an important class of therapeutic bioactive substances and play an important role in clinical practice.
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