What are the different effects of different molecular weights of sodium hyaluronate in the treatment of knee osteoarthritis?

What is Sodium Hyaluronate?

Sodium hyaluronate (SH), also known as Hyaluronic Acid, is a linear polysaccharide compound widely found in human synovial fluid and other tissues. It was first isolated in 1934 and began to be used in the treatment of osteoarthritis in 1971. Intra-articular injection of exogenous sodium hyaluronate replenishes the sodium hyaluronate lost in the synovial fluid of patients, relieving pain and improving joint function. It is an important non-surgical treatment for mild to moderate knee arthritis (KOA).

What is the molecular weight of sodium hyaluronate?

The molecular weight (SH) in kDa is the core indicator determining its physicochemical properties and efficacy. The SH molecular weight varies considerably depending on the source and process: naturally extracted sodium hyaluronate has a wide molecular weight range, while artificially synthesized sodium hyaluronate can be precisely controlled between 550-2500 kDa. The SH molecular weight of synovial fluid in healthy individuals is 6000-7000 kDa, while in KOA patients it drops to 3000-5000 kDa. Clinically, <1000 kDa is generally defined as low molecular weight, 1000-3000 kDa as medium molecular weight, and >3000 kDa as high molecular weight. Intra-articular injection preparations are mainly of low and high molecular weights.

What are the Physicochemical Differences in Sodium Hyaluronate at Different Molecular Weights? 

1) High vs. Low Molecular Weight Sodium Hyaluronate Characteristics

The physicochemical properties of sodium hyaluronate vary with its molecular weight, which affects its clinical application: 

Low molecular weight sodium hyaluronate: High hydration, good permeability, and low viscosity make it easier to inject and diffuse faster.

High molecular weight sodium hyaluronate: Forms a more stable gel, has higher viscosity, and provides a longer-lasting effect, but with greater injection resistance.

These differences determine how sodium hyaluronate interacts within the joint and its efficacy in treating knee osteoarthritis. Low molecular weight sodium hyaluronate distributes more evenly within the joint, while high molecular weight sodium hyaluronate has better retention, thus enhancing therapeutic efficacy.

What are the different therapeutic effects of sodium hyaluronate with varying molecular weights in knee osteoarthritis treatment?

Low molecular weight sodium hyaluronate (SH) has anti-inflammatory and analgesic effects; high molecular weight SH provides cartilage protection and joint lubrication.

Low molecular weight SH focuses on anti-inflammatory and analgesic effects, has strong permeability, and can quickly inhibit inflammatory mediators and relieve nerve excitation, improving pain within 1-2 weeks. It is suitable for acute flare-ups of knee osteoarthritis (KOA), but the effect only lasts for 1-2 months, requiring weekly injections. High molecular weight SH emphasizes lubrication and cartilage protection, replacing damaged synovial fluid, inhibiting cartilage degradation, and promoting cartilage repair. Its analgesic effect is slower but longer-lasting, lasting 3-6 months, requiring monthly injections. Medium molecular weight SH has efficacy between the two and is less commonly used clinically.

Is sodium hyaluronate safe for knee osteoarthritis treatment?

SH joint injections are highly safe. Adverse reactions are mostly mild local pain and swelling, which subside spontaneously within 3-7 days. High molecular weight hyaluronic acid (SH) has a slightly higher incidence of adverse reactions than low molecular weight SH (approximately twice as high), but requires less frequent injection; low molecular weight SH requires frequent injections, which may increase the risk of infection. Proper use can reduce adverse reactions. Patients with allergies or joint infections should avoid use.

Focusfreda Pharma Grade Sodium Hyaluronate FAQ: 

Q1: What are the sources of sodium hyaluronate?

Initially, it was extracted from rooster combs internationally; now, microbial fermentation is widely used for safe production.

Q2: What are the quality standards?

Focusfreda products meet pharmaceutical-grade safety and efficacy standards. Currently, pharmaceutical-grade raw materials have obtained CEP and WC certifications, and more specifications are under registration.

Q3: How is sodium hyaluronate used?

Focusfreda supplies raw materials to pharmaceutical or cosmetic companies, who manufacture related therapeutic drugs or injections. The final product is used for intra-articular injection, or as an ophthalmic viscoelastic agent, hyaluronic acid filler injection, etc.

Q4: What types of pharmaceutical-grade Sodium Hyaluronate does Focusfreda offer?

Focusfreda supplies pharmaceutical grade sodium hyaluronate raw materials includes SH-EP2.3 (CEP), SH-EP-N1.8 (KFDA), SH-EP-NO.8 (KFDA) for API; medical Device grade includes SH-MDI, SH-MDE and SH-MDN.