86
4 Alginates
Alginates in forms such as calcium alginate, sodium alginate and alginate gels
have been shown to have the effect of reducing blood sugar level when consumed
orally (Hisni et al. 2016). The mechanism by which this is achieved has been studied
to be due to the suppression of starch digestion while calcium alginate did not affect
the permeability of glucose across membranes nor bind to the glucose to prevent
absorption into the bloodstream as is the mechanism for some blood sugar lowering
substances, calcium alginate acts by inhibiting the action of the enzyme glucosidase
which breaks down starch to sugars. It is thought that at a dosage of 5% body weight
with a particle size of 53 µm, calcium alginate can aid in reducing blood sugar levels
(Idota et al. 2018). Some studies in human subject also indicate potential for alginate
gels to aid in reducing the uptake of cholesterol as well as glucose as a means of
controlling levels in the blood at a dosage of 1.5 g, reduced cholesterol and glucose
levels were measured in the test subjects. The mechanism by which this is achieved is
thought to be through the delay of the uptake by the strong gel (Paxman et al. 2008).
Retention of the glucose and cholesterol within the gel or acting as a barrier between
the intestine wall and the glucose or cholesterol could prevent or delay their uptake
into the bloodstream resulting in more of them being passed along the alimentary
canal along with the alginate fiber.
4.7.4 Biomedical Application
In tissue engineering, different forms of alginate are applied for the production of
biopolymer-based extracellular matrix (ECM) to promote tissue regeneration. Their
ability to provide stability in hydrogel formulations and maintain an aqueous environment by absorbing and retaining biological fluids makes alginates attractive for
such purpose. Advanced studies up to clinical trials on animals and humans have
been carried out on a number of alginate-based hydrogel implants for cardiac regeneration (Liberski et al. 2016). Presently, there is no cure for cardiac failure, and
treatments exist to manage cardiac illnesses. Among the potential approaches to
treat heart failure is the use of alginate-based biomaterials to achieve self-repair of
the cardiac tissue. The properties of alginate which allows them to form viscous
fluids when dissolved in water and to form hydrogel when reacted with calcium salts
such as calcium chloride make them suitable for application as injectable implants
for cardiac repair. Here, the unique hydrogel-forming property of alginate comes as
an advantage as it can form hydrogels in physiological fluid under mild temperatures
~40 °C). These hydrogels can mimic the biomechanical properties of the cardiac tissue. The biodegradability of alginate is also important for such purpose as it remains
stable enough to allow formation of the ECM, and once the tissue is regenerated, it
can biodegrade. Companies such as Life Technology Inc., LoneStar Heart. Inc and
Bellerophon BCM LLC have developed alginate-based products for cardiac tissue
regeneration, some at various stages of clinical trials such as AlgiMatrix, AlgisylLVR and PRESERVATION. Different salts of alginates with varying structures and
molecular weight are used and tailored for specific mechanism of action. In the area
4 Alginates
Alginates in forms such as calcium alginate, sodium alginate and alginate gels
have been shown to have the effect of reducing blood sugar level when consumed
orally (Hisni et al. 2016). The mechanism by which this is achieved has been studied
to be due to the suppression of starch digestion while calcium alginate did not affect
the permeability of glucose across membranes nor bind to the glucose to prevent
absorption into the bloodstream as is the mechanism for some blood sugar lowering
substances, calcium alginate acts by inhibiting the action of the enzyme glucosidase
which breaks down starch to sugars. It is thought that at a dosage of 5% body weight
with a particle size of 53 µm, calcium alginate can aid in reducing blood sugar levels
(Idota et al. 2018). Some studies in human subject also indicate potential for alginate
gels to aid in reducing the uptake of cholesterol as well as glucose as a means of
controlling levels in the blood at a dosage of 1.5 g, reduced cholesterol and glucose
levels were measured in the test subjects. The mechanism by which this is achieved is
thought to be through the delay of the uptake by the strong gel (Paxman et al. 2008).
Retention of the glucose and cholesterol within the gel or acting as a barrier between
the intestine wall and the glucose or cholesterol could prevent or delay their uptake
into the bloodstream resulting in more of them being passed along the alimentary
canal along with the alginate fiber.
4.7.4 Biomedical Application
In tissue engineering, different forms of alginate are applied for the production of
biopolymer-based extracellular matrix (ECM) to promote tissue regeneration. Their
ability to provide stability in hydrogel formulations and maintain an aqueous environment by absorbing and retaining biological fluids makes alginates attractive for
such purpose. Advanced studies up to clinical trials on animals and humans have
been carried out on a number of alginate-based hydrogel implants for cardiac regeneration (Liberski et al. 2016). Presently, there is no cure for cardiac failure, and
treatments exist to manage cardiac illnesses. Among the potential approaches to
treat heart failure is the use of alginate-based biomaterials to achieve self-repair of
the cardiac tissue. The properties of alginate which allows them to form viscous
fluids when dissolved in water and to form hydrogel when reacted with calcium salts
such as calcium chloride make them suitable for application as injectable implants
for cardiac repair. Here, the unique hydrogel-forming property of alginate comes as
an advantage as it can form hydrogels in physiological fluid under mild temperatures
~40 °C). These hydrogels can mimic the biomechanical properties of the cardiac tissue. The biodegradability of alginate is also important for such purpose as it remains
stable enough to allow formation of the ECM, and once the tissue is regenerated, it
can biodegrade. Companies such as Life Technology Inc., LoneStar Heart. Inc and
Bellerophon BCM LLC have developed alginate-based products for cardiac tissue
regeneration, some at various stages of clinical trials such as AlgiMatrix, AlgisylLVR and PRESERVATION. Different salts of alginates with varying structures and
molecular weight are used and tailored for specific mechanism of action. In the area