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Marine Polysaccharides in Pharmaceutical Applications
Published in Se-Kwon Kim, Marine Biochemistry, 2023
Riyasree Paul, Sourav Kabiraj, Sreejan Manna, Sougata Jana
Hyaluronan is glycosaminoglycans (GAG) based linear mucopolysaccharide containing alternative units of uronic acid and N-acetylated hexosamine in a repeating configuration. Hyaluronan is a non-sulfated polysaccharide, which is commonly known as hyaluronic acid. It is a negatively charged heteropolysaccharide. This marine polysaccharide consist of D-glucuronic acid unit and N-acetyl-D-glucosamine unit linked with glycosidic bonds (Gupta et al. 2019). Hyaluronic acid is commonly used in the cosmetic industry, tissue regeneration, wound healing, cell proliferation and as a polymer in drug delivery application (Goldberg and Buckwalter 2005). Apart from these, it is also used as a biological marker in determining the fraction of synovial fluids in different body joints for arthritis patients (Papakonstantinou et al. 2012).
Structure and Function of Cartilage
Published in Kyriacos A. Athanasiou, Eric M. Darling, Grayson D. DuRaine, Jerry C. Hu, A. Hari Reddi, Articular Cartilage, 2017
Kyriacos A. Athanasiou, Eric M. Darling, Grayson D. DuRaine, Jerry C. Hu, A. Hari Reddi
Water is the main liquid component in articular cartilage, as well as in the synovial fluid present in the joint capsule. Synovial fluid is a viscous liquid within the joint possessing non-Newtonian properties. Synovial fluid, which as we discussed earlier is derived from interstitial fluid as a blood ultrafiltrate, provides nourishment and waste product removal, and has a critical function in lubrication. Synovial fluid contains large amounts of hyaluronic acid (∼3 mg/ml) (Decker et al. 1959) and other lubricating molecules (such as SZP/lubricin/PRG4) secreted by specialized tissues lining the joint. Synovial fluid also functions to provide a smooth layer to the articular cartilage by filling in valleys between asperities on the cartilage surface. This layer is replenished not only from the reserve fluid in the joint space but also from fluid exuded from the cartilage matrix. These actions maintain a layer of fluid at the articulating surface, enabling “weeping lubrication” to produce the low-friction surface necessary for cartilage function. The non-Newtonian properties of synovial fluid (provided mostly by the viscosity enhancement of hyaluronic acid) allow for absorption of shock as the fluid viscosity increases at the moment shear is applied. However, synovial fluid then immediately decreases in viscosity and thins with prolonged stress.
Measurement Method for Orthopaedics
Published in P. Arpaia, U. Cesaro, N. Moccaldi, I. Sannino, Non-Invasive Monitoring of Transdermal Drug Delivery, 2022
P. Arpaia, U. Cesaro, N. Moccaldi, I. Sannino
In order to facilitate fluid bending/straightening motions and to protect the joint against weight-bearing stresses, as well as to reduce the internal friction in the joint, all articular surfaces are covered with cartilage, a special protective and flexible connective tissue. The synovial fluid is the thick liquid that lubricates joints and keeps them moving smoothly. The knee joint is enclosed by a joint capsule, with four sturdy ligaments: two collateral ligaments placed along the sides of the knee that gives stability to the knee, limiting the sideways motion. Instead, two cruciate ligaments, crossing within the joint, connects the tibia to the femur for controlling rotation, forward and backward movements of the tibia [185, 186].
Comparative study on the mechanical behavior of the interface between natural cartilage and artificial cartilage
Published in Soft Materials, 2021
Yuhe Fan, Guangyi Zhou, Guitang Zhang, Feng Li
The function of synovial fluid is to lubricate the friction between the femur and the natural cartilage. Severe arthritis or joint necrosis will lead to the decrease of synovial fluid production. The use of artificial cartilage to replace the damaged transparent cartilage will not produce synovial fluid in the prosthesis tissue, so the lack of synovial fluid will lead to the loosening of the prosthesis, thus affecting the life of the artificial cartilage.[57] Domestic and foreign cartilage lubricants pure water, Ringer’s solution, hypertonic acid, sodium hyaluronate solution, calf serum, etc., are used as lubricating fluid in most studies.[58–60] Feng L [61] et al. pointed out in the friction and wear experiment of natural cartilage and medical stainless steel that when the lubricating liquid changed from normal saline to hypertonic acid, the friction coefficient decreased from 0.148 to 0.132. Yang Z et al.[62] pointed out in the comparative experiment of the friction behavior of articular cartilage with two kinds of lubricating media that the contact angle of cartilage surface became larger, the friction coefficient became smaller and the deformation of cartilage became smaller when the normal saline was changed to calf serum. The tribological behavior of UHMWPE on a hip joint simulator by Raffi N. M et al.[63] pointed out that contact load and melt temperature are the main factors affecting the tribological properties of UHMWPE. The effective component of natural lubricating liquid is polysaccharide hypertonic acid. The results showed that there was a linear increasing trend, which indicated that the lubricant without activator would affect the service life of artificial cartilage; the activator of hypertonic acid + γ-globulin/ activator, hypertonic acid + Lα-DPPC/ phospholipid, hypertonic acid + γ-globulin/ + Lα-DPPC/ phospholipid could reduce the service life of artificial cartilage. From Figure 15 (b), it can be seen that when the compression amount is 10%, Maximum real maximum principal stress value of PVA hydrogel and hypertonic acid increased from 0MPa to 83769.2 MPa, and the maximum principal stress values of hypertonic acid +γ -globulin/ activator, hypertonic acid +Lα-DPPC/ phosphatidylcholine, hypertonic acid + γ-globulin/ +Lα-DPPC/ phospholipid were 2856.59 MPa, 2102.78MPa, and 1678.35 MPa respectively. This shows that the maximum true principal stress between the artificial cartilage and the femur can be significantly reduced by using the activator of hypertonic acid + γ-globulin/ + Lα-DPPC/ phospholipid, and the effect of reduction is better than that of hypertonic acid + γ-globulin/ activator, hypertonic acid + Lα-DPPC/ phospholipid activator.