Author Archives: Vistpharma

Tamarind Seed Polysaccharide (TSP) is a natural molecule obtained from the tamarind tree and has been used in the food industry for a long time. It is effective in the treatment of dry eye syndrome due to its remarkable similarity with mucins, which are ocular surface molecules.

TS-Polysaccharide is a natural substance extracted from the seeds of the Tamarindus indica plant. Chemically, it is a water-soluble galacto-xylo-glucan polysaccharide with a medium molecular weight of 470 kDa.

It has properties such as high viscosity, wide pH tolerance and stickiness, so it has been used as a stabilizer, thickener, gelling agent and binder in the food and pharmaceutical industries. In addition, it has the properties of non-carcinogenicity, mucoadhesiveness, biocompatibility and high drug retention capacity.

Tamarind Seed Polysaccharide

Tamarindus indica

TS-Polisakkaridin karakteristik müsin benzeri yapısı

It is thought that the increased residence time on the eye surface with Tamarind Seed Polysaccharide can be explained by the similarity of its structure to transmembrane mucins.

Mucins are a group of extremely bulky heterogeneous glycoproteins that can be found as major components in all mucus secretion of moist epithelial surfaces. On the ocular surface, epithelial mucins act as a preocular tear film stabilizer to prevent dehydration of the underlying epithelium, a remarkable barrier against penetration of pathogens and wetting of the epithelial surface of the cornea and conjunctiva during blinking and lubricating substance.

The molecular structure of Tamarind Seed Polysaccharide of the “mucin-like” type is very similar to mucus glycoproteins and MUC 1, a mucin found in the cornea and conjunctiva, especially in its extracellular projection in the glycocalyx.

The branched structure of Tamarind Seed Polysaccharide, which is typical of tear film glycoproteins, allows the polysaccharide to adhere directly to the mucins of the glycocalyx. This interaction gives the molecule a higher residence time on the ocular surface than the most effective product previously available, Hyaluronic acid. Additionally, since the polymer has a high water retention capacity, Tamarind Seed Polysaccharide-based solutions ensure proper hydration of the ocular surface and increase the stability of the pre-corneal tear film, protecting it from environmental hazards by creating a microenvironment suitable for corneal surface repair processes.

Characteristic mucin-like structure of TS-Polysaccharide

Patent for eye drops containing TSP

In 1990, the collaboration of Farmigea, the University of Pisa and Polytech on the study and characterization of Tamarind Seed Polysaccharide led to the product currently used.

On February 5, 1996, an Italian patent application numbered 1,283,911 was filed for “Ophthalmic solutions made viscous with Tamarind Seed Polysaccharide” and was subsequently approved. Farmigea’s challenge during 1998-2001 was to determine whether Tamarind Seed Polysaccharide was a drug suitable for clinical development. During 2002-2005, Farmigea’s challenge was to prove Tamarind Seed Polysaccharide as an effective compound for the treatment of dry eye syndrome[SS1] [SS2] [SS3].

Properties of TSP in the treatment of dry eye syndrome

The rheological behavior of Tamarind Seed Polysaccharide solution is non-Newtonian, accurately mimicking tear fluid, being very viscous when the eyelids are open and more fluid during blinking due to the stress of closing the eyelids. As a result, Tamarind Seed Polysaccharide ophthalmic solutions ensure proper protection of the ocular surface by preventing blinking discomfort.

In terms of the properties of the polymer described above, ophthalmic solutions containing Tamarind Seed Polysaccharide are effective in maintaining proper hydration of the ocular surface by engaging with the tear film and reducing evaporation. By adhering directly to the superficial layer of the corneal epithelium, Tamarind Seed Polysaccharide can form an efficacy barrier that protects the eye from all attacks caused by external factors such as wind, prolonged exposure to sunlight, dry air, chlorinated or salt water, intense sunlight and air conditioning, irritation, burning that may occur. Prevents redness and foreign body sensation. Tamarind Seed Polysaccharide in preservative-free ophthalmic solution can also reduce discomfort caused by wearing contact lenses for long periods of time.

 [SS2]https://www.farmigea.co.uk/the-tamarind-seed-polysaccharide/

 [SS3]https://www.farmigea.co.uk/dry-eye-syndrome/

Resources:

• Ophthalmic solutions viscosified with tamarind seed polysaccharide, Saettone MF, Burgalassi S, Giannaccini B, Boldrini E, Bianchini P, Luciani G, European Patent EP0892636.
• Use of a new lachrymal substitute (TS Polysaccharide) in Contactology, Mannucci LL, Fregona I, Di Gennaro A, J Med Contactology and Low Vision 2000, 1(1): 6–9
• A scintigraphic investigation of the precorneal residence time of TS polysaccharide formulations in mild to moderate KCS patients, B. Lindsay, T. Jones, B. Brown, S. Osborne, C.G. Wilson, E.
• Development of a Simple Dry Eye Model in the Albino Rabbit and Evaluation of Some Tear Substitute, S. Burgalassi, L. Panichi, P. Chetoni, M. F. Saettone, E. Boldrini, Opthalmic Research 1999;31:229-35.
• Effect of Xyloglucan (TSP) on conjunctival cell adhesion to laminin and on corneal epithelium wound healing, S. Burgalassi, L. Raimondi, R. Pirisino, G. Banchelli, E. Boldrini, M. F. Saettone, Eu. J. of Ophthalmology 2000 Jan-Mar;10:71-6.
• Assessment of spontaneous contamination and evolution over tiem of pathogens introduced into ophthalmic formulations with a new lacrimal substitute (TAMARIND SEED POLYSACCHARIDE) after first opening, E. A. Debbia, E. Boldrini, I.Gualco, A.M. Schito, A. Marchese, Italian Journal of Dental and Clinical Microbiology
• Interaction between contact lenses and artificial tears: a Nuclear Magnetic Resonance Study, N. Pescosolido, L. Casciani, C. Castro, C. Manetti, ATO, 2004.
• Comparison between two tear substitutes in contact lens wearers, A,V, Bux, S.Z. Scalinci, L. Scorolli, M.C. Morara, R. Meduri, ATO, 2003.
• Establishing the tolerability and performance of tamarind seed polysaccharide (TSP) in treating dry eye syndrome: results of a clinical study, M. Rolando & C. Valente; BMC Ophthalmology volume 7, Article number: 5, 2007

A complex syndrome with a high impact on visual functionality.

The ocular surface is normally covered by a hydrolipidic tear film that can protect the corneal and conjunctival epithelium from the external environment.

Evidence supports a two-layer model of the tear film, comprising a thin surface lipid layer overlying a thicker mucous-aqueous mixed layer.

The mucin component of this final layer helps wet the surface of the eye, allowing the component to spread across a surface that is not normally wet.

In case of exposure to external or environmental stressors such as wind, sun, dry air, salt water, smoke, bright light, air conditioning, high temperatures, long-term computer use or contact lens wear, the tear film may change or become so inadequate that it cannot fulfill its protective function. It can also cause symptoms such as irritation, burning, redness and foreign body sensation, which are typical symptoms of dry eye.

Conditions that affect the surface of the eye, such as changes in the tear film, vitamin A deficiency, eye allergies, and the use of preservatives in topical medications.

Kuru Göz mekanizması ve tanımı

“Gözyaşı filminin homeostazisinin kaybıyla karakterize edilen ve oküler semptomların eşlik ettiği, gözyaşı filmi instabilitesi ve hiperosmolaritenin, oküler yüzey inflamasyonunun ve hasarının ve nörosensör anormalliklerinin etiyolojik rol oynadığı oküler yüzeyin kuru multifaktöriyel hastalığı.” (Definition of Tear Film & Ocular Society Dry Eye Workshop II).

LASIK surgery and Dry Eye Syndrome

The change in the tear film can be determined by decreased production of tear fluid or increased evaporation of the same fluid, decreased sensitivity of the ocular surface, especially as it can occur with ocular surface inflammation, contact lenses, corneal surgery – including refractive surgery, leading to decreased aqueous production of the lacrimal glands. Dry eyes are an extremely common result of LASIK (Laser-Assisted in Situ Keratomileusis) surgery (laser-assisted in-situ shaping of the cornea).

Corneal and conjunctival epithelial damage

In general, in critical situations such as ocular surface inflammation, contact lenses, corneal surgery, the cornea and conjunctiva epithelium are more exposed to the entry of pathogens and erosion caused by the constant friction of the eyelid against the eye surface. Epithelial damage is demonstrated histologically by a decrease in the number of goblet mucipar cells and abnormal structures of the corneal and conjunctival epithelium and their constituent cell membranes. This type of damage is detected clinically by colorimetric analysis with specific dyes (Fluorescein, Rose Bengal or lissamine green) and the degree of staining determines the cause of ocular dryness.

Artificial tear treatment

Artificial tears are used as the first therapeutic option for treating any stage of dry eye and contain ophthalmic solutions that can properly moisturize and lubricate the ocular surface. These ophthalmic solutions are often designed using the chemical and physical properties of hydrophilic polymers, which have a moisturizing and lubricating effect by retaining water on the ocular surface.

The ideal composition should be compatible with the physiological properties of the ocular surface epithelium and be able to create a microenvironment in which the epithelium can restore its normal structure and functions in case of damage.

Resorces:

•Changes in the tear film and ocular surface from dry eye syndrome, Johnson ME and Murphy PJ, Progr in Retinal and Eye Res, 2004:23, 449-474.

• Post-LASIK dry eye. Roni M Shtein. Expert Rev Ophthalmol. 2011 October ; 6(5): 575–582

• Tear film and ocular surface tests in animal models of dry eye: uses and limitations, Barabino S, Chen W and Dana MR., Exp Eye Res, 2004: 79, 613-621.

• Artificial tear solutions, Lemp MA, Int Ophthalmol Clin 1973:13, 221-9

• Menoapuse and dry eye. A possible relationship, Versura P, Campos EC, Gynecol ENdocrinol. 2005 May; 20(5): 289-98, Review.

• TFOS DEWS II Report Executive Summary. Jennifer P. Craig, J. Daniel Nelson, Dimitri T. Azar, Carlos Belmonte, Anthony J. Bron, Sunil K. Chauhan, Cintia S. de Paiva, Jos e A.P. Gomes, Katherine M. Hammitt, Lyndon Jones, Jason J. Nichols, Kelly K. Nichols, Gary D. Novack, Fiona J. Stapleton, Mark D.P. Willcox, James S. Wolffsohn, David A. Sullivan. The Ocular Surface (2017)

Elderberry is a plant species belonging to the Adoxaceae family. Although the majority of varieties grow in forests and parks, there are also varieties grown for industrial purposes.

Elderberries (Sambuci fructus) are drupes. Their color depends on the stage of maturity. Initially the fruit is green but turns black and purple when fully ripe. Due to the health beneficial properties of elderberry fruits resulting from their rich chemical composition, this raw material is widely used in industry.

The chemical composition of elderberry fruits depends on various factors such as variety, environmental conditions (light, temperature, amount and frequency of rainfall, fertilization, cultivation methods), processing method and storage conditions. Besides containing a small amount of protein (2.7-2.9%), elderberry is also rich in fatty acids. Apart from this, elderberries also contain essential oil consisting of more than 30 different compounds. Elderberry fruits are also a source of minerals and contain various vitamins in their structure.