Liposomal Vitamin C, a Nano Solution for Knee Health


Did you know that osteoarthritis affects more than 50% of over 60 year olds?

This disease, indeed, is the most common degenerative joint disorder that affects both small and large joints and it is a leading cause of disability in older adults. The knee is the principal peripheral joint affected resulting in progressive loss of function, pain and stiffness with a negative impact on health-related quality of life.

Because this disease is so prevalent the relevance of this disease, let’s discover together its pathology, risk factors and treatment options to prevent/retard the progress of osteoarthritis and maintain the knee’s function and health.

Impact of Osteoarthritis on Cartilage and Collagen

Osteoarthritis significantly impacts articular cartilage, which gets severely degraded over the course of the disease. The figure below shows a comparison between healthy (left) and osteoarthritic (right) cartilage in the knee.

Articular cartilage is a specialized type of connective tissue found at the end of long bones and within the intervertebral discs. Its unique structure forms a smooth and lubricated surface that allows for a proper joint motion with a low friction coefficient, good shock-absorbing capabilities and minimized pressure on the bone.

Water accounts for 65–80% of the weight of cartilage providing it the possibility of deformation under load, while 10-15% is made up of collagen, which provides tensile strength (defined as the ability to resist a force that tends to pull the system apart).

Notably, type II collagen constitutes 90% to 95% of the total collagen and is specific to articular cartilage. Although it is normally resistant to degradation, specific enzymes called collagenases, are able to degrade it and they have been implicated in the pathogenesis of osteoarthritis.

A measurable increase in type II collagen degradation is seen in an early stage of the disease with a net loss of this type of collagen. This is accompanied by an increase in the synthesis of collagen II to reconstitute the physiological and functional properties of the cartilage.

However, the newly synthesized molecules are often damaged, compromising any effective attempts at cartilage repair.

Osteoarthritis is a multifactorial disease that affects the entire joint.  Due to the intimate contact between bone and cartilage, any changes in either tissue will influence the other components (the figure above shows the loss of cartilage and how the bone structure is remodeled).

Risk Factors for Cartilage Loss 

There are multiple risk factors for cartilage loss in osteoarthritis. As shown in the image below, the aetiology of this disease is a complex interplay between genetic and environmental factors.

Generalized constitutional factors are related to age, obesity and occupation, adverse mechanical factors include trauma, surgery on the joint structures while some genetic syndromes lead to joint malformations and early-onset osteoarthritis.

By analyzing these risk factors and considering the fact that knee injuries are associated with accelerated osteoarthritis, it is evident that nobody can feel safe!

Thus, let’s discover together the treatment options.

The Therapeutic Challenge of Osteoarthritis

Unfortunately, there are no approved drugs able to stop the disease progression and pharmacological treatments aimed at osteoarthritis are mostly to combat symptoms like pain.  On the other hand, non-pharmacological treatments include exercise, physiotherapy, weight loss, and surgical joint replacements.

On the basis of the fact that once the collagen network is degraded, it cannot be repaired to its original state, the crucial therapeutic challenge is the prevention of these damages.

In this context, the regulation of oxidative stress, which has been described to play an important role in the pathogenesis (a fancy term for how you get sick) of osteoarthritis, offers a promising therapeutic approach.

Although reactive oxygen species (free radicals responsible for oxidative stress) at moderate levels are essential in many physiological processes of our body, their overproduction in the knee joints is responsible for the destruction of the articular cartilage. Oxidative stress is also strictly correlated with the severity of osteoarthritis of the knee.

Oxidative stress is also strictly correlated with the severity of osteoarthritis of the knee.

Collectively, it has been demonstrated that oxidative stress has a double negative effect:

  1. decreases in the synthesis of collagen II;
  2. promotes the breakdown of molecules of type II collagen.

Do not forget that type II collagen constitutes 90% to 95% of the total collagen of the articular cartilage!

Thus, the maintenance of optimal levels of free radicals is essential for healthy knee joints. Normally, our body gets rid of the excess of free radicals using natural antioxidants such as vitamins C and E, glutathione and various enzymes.

Vitamin C, in particular, is not only a powerful antioxidant but also plays a key role in collagen production. As reported in the image below, limited vitamin C intake is associated with an increased risk of joint injury and pain, cartilage loss and osteoarthritis.

This body of evidence provides for the rationale that a good bioavailability of vitamin C may retard the progress of osteoarthritis.

Vitamin C

Vitamin C (ascorbic acid) is a water-soluble vitamin that was first isolated in 1923 by Nobel laureate Szent-Gyorgyi. The excellent antioxidant effect of vitamin C is due to the fact that it can exist both in reduced (ascorbate) and oxidized forms as dehydroascorbic acid which are easily inter-convertible and biologically active.

Roles and Benefits of Vitamin C

Ascorbic acid is not only an important co-factor for collagen production, the body requires vitamin C also for normal physiological functions essential for our health. It takes part in enzyme activation, oxidative stress reduction and immune system response and contributes to brain health playing a role in Central Nervous System functions.

Vitamin C also helps in the synthesis and metabolism of tyrosine, folic acid and tryptophan and facilitates the conversion of cholesterol into bile acids. Furthermore, some academic articles have shown that it protects against respiratory tract infections and reduces the risk of cardiovascular disease (i. e. hemorrhagic stroke) and certain cancers.

Even though it has so many key roles, our body cannot synthesize ascorbic acid (from glucose) due to the deficiency of the specific enzyme (gluconolactone oxidase). Thus, vitamin C has to be obtained from the diet.

Let the food be the medicine and the medicine be the food

This phrase, stated by Hippocrates around 2500 years ago, seems to be more accurate than ever!

Dietary Sources of Vitamin C 

Vitamin C is found in a variety of fruits (i.e. citrus fruits, kiwi, etc.), vegetables (green and red peppers, broccoli, etc.) and juices while animal sources are poor in it (<30–40 mg/100 g).

Vitamin C content, evaluated by the food, is reported in the table below, however, it is important to highlight that the stability of this vitamin is precarious and highly influenced by oxygen, heat, pH, and metallic ions. It is well preserved in frozen foods, indeed, the vitamin C losses during vegetable and fruit storage are up to 70%.

Cooking also reduces the vitamin C content of vegetables by 40% to 60%.

When we think of vitamin C, we probably consider oranges and orange juice as good sources, thus it is interesting to learn that orange juice reconstituted from frozen concentrate is a better source of vitamin C as compared with liquid ready-to-drink juice (86 mg per serving vs 39-46 mg per serving).

Fertilization also impacts vitamin C content: the highest concentrations of vitamin C are usually recorded in fruits and vegetables from organic farming.

How Much Vitamin C Does Your Body Need?

Recommended doses of vitamin C range from 45 mg/day to 155 mg/day. In the table below are reported the reference intake values for children, adolescents, males, females and smokers. Elderly people require higher intakes because of their lower blood concentrations of vitamin C which may be due to chronic diseases or other factors like permanent medication, but not to an effect of aging itself.

Smokers have more metabolic losses and consequently lower plasma levels of vitamin C than non-smokers. Interestingly, when smokers stop smoking, their vitamin C plasma levels increase.

Vitamin C is transported in the plasma as ascorbate. As described earlier, ascorbate is the reduced form of vitamin C. The plasma ascorbate concentration is a good indicator of the vitamin C status. A plasma ascorbate concentration of 50 μmol/l or higher represents an adequate status while levels between 10 and 50 μmol/l indicate an increased risk of deficiency which requires a vitamin C dietary supplement.

Since vitamin C deficiency is a risk factor in the development of knee osteoarthritis, the correction of its concentration is crucial both for primary prevention and as a therapeutic intervention.  In addition, vitamin C supplement has been found to yield multiple potential pain-reduction benefits in knee osteoarthritis.


Vitamin C Supplements

Several strategies can be used for the correction of vitamin C deficiency.

The first recommendation is a diet rich in vegetables and fruits which naturally contain vitamin C, however, it might not work! In many diseases and in people with very poor vitamin C status, including smokers, the dietary intake may be insufficient to provide adequate amounts of vitamin C.

If you wonder why, the answer is the bioavailability of vitamin C.

In pharmacology, bioavailability, also defined as absorption rate, is the fraction of an administered dose of a substance that reaches the systemic circulation.

The absorption rate of vitamin C is 80% or higher for vitamin C dosages from 15 to 100 mg/day and drops to less than 50% at an intake level of 1250 mg/day. Thus, the higher the vitamin C intake, the lower the adsorption rate!

Following food ingestion, the bioavailability of vitamin C is largely determined by rates of intestinal absorption and further influenced by renal reabsorption and excretion. Anyway, stomach acid does not destroy ascorbic acid but simply oxidizes it to dehydroascorbic acid which is still effective.

Unfortunately, even the assumption of vitamin C through capsules or effervescent tablets, which represents a daily routine for many people, leads to the same diminishing returns as food.

Traditional supplements of vitamin C (usually in the form of sodium ascorbate)

Photo by Adam Nieścioruk on Unsplash


Oral administration–swallowing a pill– of traditional supplements that usually contain vitamin C in the form of sodium ascorbate, indeed, is made ineffective by the slow and regulated pattern of intestinal absorption of ascorbic acid.

Infusion of vitamin C, via arteries or veins, is extremely efficient. By definition, when a medication is administered intravenously, its absorption rate is 100%. This vitamin C supplement, bypassing the dependency on intestinal absorption, results in high circulating plasma concentrations that will remain constant until the infusion is discontinued.

On the other hand, giving your self Vitamin C shots is impractical. You could give yourself an infection, discomfort and phlebitis. I don’t know about you, but I hate shots anyway!

That’s why, liposomal vitamin C, a supplement of vitamin C encapsulated in liposomes, is showing promise and may become the Holy Grail of vitamin C supplementation.

Liposomal Vitamin C

Dietary supplements based on liposomal vitamin C exploit the unique properties and advantages of liposomes to override the limitations of vitamin C absorption.

What Are Liposomes?

Liposomes are nanoparticles of spherical shape that can be synthesized from cholesterol and other phospholipids. The similarity of liposomes to cell membranes (which are made of phospholipids) provides unique opportunities for the delivery of drugs into target cells. The image below shows the structure of a liposome with a focus on phospholipids.


Liposomes have a long and successful clinical history as drug delivery systems because of their ability to:

  1. protect the payload (drugs, nutrients, vitamins, etc.) from premature degradation in the biological environment;
  2. enhance the bioavailability;
  3. prolong the presence in the blood;
  4. deliver to target cells more precisely with a controlled release.

These nanoparticles are non-toxic, biocompatible and biodegradable and their size and chemical-physical properties can be precisely controlled during the synthesis obtaining tailored nanocarriers.

Another key advantage of a liposomal delivery system is the ability to encapsulate and store both hydrophilic and hydrophobic molecules. It is due to the fact that phospholipids tails are nonpolar (hydrophobic) while phospholipids heads are polar as reported in the image above. The image below clearly shows that hydrophilic vitamins like vitamin C stay in the liquid aqueous compartment of liposomes while the lipophilic ones are adsorbed in the membrane made of phospholipids tails.

Applications of liposomes

Because of these unique properties, liposomes are the most successful drug delivery system with more than 12 nanodrugs approved by the Food and Drug Administration (i. e. Doxil®/Caelyx®, Myocet®, etc). Initially, liposomes have been exploited in cancer therapy to improve the efficiency of chemotherapeutics. Later, pharmaceutical and food industries have started to extensively study the use of liposomes to encapsulate bioactive elements, nutrients and antioxidants, including vitamin C.

In this context, liposomal vitamin C has gained more and more attention in academic research resulting in the publication of many articles focused on the exploitation of liposomes as vitamin C transporters to safely deliver this key molecule to target cells.

Clinical studies on oral liposomal vitamin C have clearly demonstrated the ability of liposomes to increase vitamin C bioavailability almost 2 times more than an equivalent dose of unencapsulated molecule. These good results are the demonstration that the liposomal technology protects ascorbic acid from premature degradation, reduces its absorption by intestinal and renal systems extending its circulation in blood.

PuraTHRIVE® Liposomal Vitamin C as a dietary supplement

Among the plethora of liposomal vitamin C products, the PuraTHRIVE® Liposomal Vitamin C, a liquid formulation made in the United States, can be considered as the golden standard of vitamin C supplements.

The image below shows a comparison among standard vitamin C supplements, intravenous vitamin C and PuraTHRIVE Liposomal Vitamin C. It is interesting to observe that PuraTHRIVE Liposomal Vitamin C represents the best compromise between the efficiency of an intravenous supplement and the affordability and easy-administration of standard pills of vitamin C.

This innovative product is a safe, non-GMO, biodegradable and effective liquid source of vitamin C which is indispensable for knee health and more in general for our body well being.

Although PuraTHRIVE® Liposomal vitamin C is a preparation for the entire family, supplementation is required in case of deficiency or in a period of intense stress. Thus, the main targets for a routine use of this product are smokers, adults over 65 years of age, patients with chronic diseases, injury and osteoarthritis (after consulting a physician, practitioner).

Purathrive Liposomal Vitamin C

Ingredients like citrus oils and vanilla extracts (non-GMO) make PuraTHRIVE Liposomal Vitamin C a pleasant-tasting liquid supplement. The serving dose is 15 ml (1000 mg of ascorbic acid) and it is also possible to mix it into any liquid such as smoothies but it is important to not exceed the dosage.

Although vitamin C is not believed to cause serious adverse effects in case of high intakes (more than 2000 mg/day) complaints are usually diarrhea, nausea and abdominal cramps, this issue is still a matter of discussion.

To recap, although knee osteoarthritis is the most common degenerative joint disorder, nowadays there is no disease-modifying osteoarthritis drug.

– PuraTHRIVE Liposomal Vitamin C is not a specific drug for osteoarthritis! PuraTHRIVE Liposomal vitamin C is a dietary liquid supplement and is not intended to diagnose, treat, cure or prevent any disease 

However, since vitamin C deficiency is a risk factor in the development of knee osteoarthritis, its supplementation is crucial (not only for knee health but also to boost the immune system and for other essential physiological processes of our body). Among the plethora of supplements, liposomal vitamin C, and in particular PuraTHRIVE Liposomal Vitamin C, by bringing together the best of standard supplements and infusion, represents a revolutionary liquid source of vitamin C both in terms of efficiency, safety and cost-effectiveness, and it is also non-GMO!

To find out more information and how to get Purathrive, click on the link!

Thanks for Reading!

About the Author, Valentina Colapicchioni, Ph. D.

Valentina Colapicchioni is a Scientific Writer and Researcher in Chemical Sciences. She has been working in several academic institutions across Europe:  CNR – National Research Council (Italy), Centre for Life Nano Science (CLNS@Sapienza) at the Italian Institute of Technology- IIT, Centre for BioNano Interactions (CBNI) at the University College Dublin (Ireland) and the University of Rome La Sapienza where she took an active role in several research projects.

Part of her research is focused on preparative

nano-chemistry for diverse range of biomedical applications including

development of organic (liposomes, polymers, etc). and inorganic

nanoplatforms (silica, quantum dots, etc.) for targeted delivery of drugs, genes

and vitamins.

Her work aimed at better understanding the

interactions of liposome-based nanoparticles with biological fluids after their

introduction in the bloodstream. Dr. Colapicchioni and co-workers have developed

several liposome formulations with a distinct skill in killing human prostate

and breast cancer cells.


addition to her extensive experience in the field of Nanomedicine, Dr.

Colapicchioni investigates the health and environmental risks correlated with

the emission of organic micropollutants.


of research: Nanomedicine, Liposomes,

Nanoparticle Synthesis and Characterisation, Bio-Nano Interactions, Proteomics,

Cancer Therapy, Organic Micropollutants, Chemical Sciences.



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