GAG 研究:TOWNSEND LETTER 美國醫學期刊 (4) 探討 GAG



醣胺聚醣(GAG)
青邊貽貝提供豐富的 GAG 醣胺聚醣(約12%),這是軟骨和關節中滑液的主要成分。 GAG 由軟骨細胞和其他局部組織所合成,是關節穩定、減震必要的成份。GAG 是複雜的氨基糖,含有磷酸鹽或硫酸鹽基團,與水一起作用即可進入軟骨基質的吸收,對關節潤滑和減震功能極為重要。但是這種「水合作用」隨著年齡的增長而降低,GAG 若損失將導致關節僵硬,並且增加了受傷的可能性。

Glycosaminoglycans (GAGs)
Perna canaliculus provides a rich source of glycosaminoglycans ( approximately 12 % GAGs ) , which are principle components of cartilage and the synovial fluid found in the joint. GAGs are synthesized by the chondrocytes and other local tissues and are essential in stabilizing the joint and providing shock-absorption.GAGs are complex amino sugars that may contain phosphate or sulfate groups that increase the uptake of water into the cartilage matrix. This "hydration" of joints, which decreases with age, is critical to the lubrication and shock absorption property of joints. A loss of GAGs leads to greater stiffness in the joint and increased potential for injury .

有九種主要類別的醣胺聚醣(GAG),它們是由複合糖(二糖重複單元)組成的長的無支鏈。五種與結締組織相關的GAG是:
  • 硫酸軟骨素-4 (Chondroitin-4-Sulfate)
  • 硫酸軟骨素-6 (Chondroitin-6-sulfate)
  • 硫酸角質素 (Keratin sulfate)
  • 硫酸皮膚素 (Dermatan sulfate)
  • 透明質酸 (Hyaluronic acid)
硫酸軟骨素-4和硫酸軟骨素-6 是構成骨和軟骨的基本基質。透明質酸是在蛋白多醣結構中發現的非硫酸化GAG,有助於滑膜的粘度。除了滑膜的潤滑之外,GAG 還為關節軟骨提供柔韌性彈性和拉伸強度。

There are nine principle classes of glycosaminoglycans (GAGs), which are long, unbranched chains made up of complex sugars (disaccharide repeating units). Five GAGs that have relevance to connective tissue are:
Chondroitin-4-Sulfate
Chondroitin-6-sulfate
Keratin sulfate
Dermatan sulfate
Hyaluronic acid

Chondroitin-4-Sulfate and Chondroitin-6-Sulfate make up the basic ground substance of both bone and cartilage. Hyaluronic Acid is a non- sulfated GAG found in the proteoglycan structure and it also contributes to the viscosity of the synovial luid. In addition to lubrication of the synovial membranes, GAGs provide flexibility elasticity and tensile strength to the articular cartilage.

關節炎的嚴重程度與關節和周圍軟骨內 GAG含量的損失直接相關。作為 GAG 的來源,青邊貽貝可以為軟骨細胞提供硫酸軟骨素和其他前體,這些前體可以改善滑液的粘度並增強關節軟骨中蛋白多醣的合成。這種功能對於逆轉關節炎過程極為重要,GAG還可以對結締組織發揮強烈的抗炎作用,有證據表明它們有效地抑制了降解酶的作用,這有助於軟骨的正常代謝。

The severity of arthritis is directly related to the loss of GAG content within the joint and surrounding cartilage. As a source of GAGs, Perna can provide the chondrocytes with chondroitin sulfates and other precursors needed to improve the viscosity of the synovial fluid and enhance synthesis of the proteoglycans in the articular cartilage. Such support is critical for reversing the arthritic process. GAGs can also exert a strong anti-inflammatory action on connective tissue. Evidence suggests that they effectively inhibit the action of degrading enzymes, which contribute to cartilage breakdown.


青邊貽貝如何改善關節功能?

青邊貽貝用於控制及逆轉關節炎的確切機制尚不清楚,但過去20年的研究表明,青邊貽貝含有許多潛在的活性化合物,可以對抗發炎和退化性關節病的破壞性循環。生物活性化合物、複合礦物質、GAG 醣胺聚醣(硫酸軟骨素)、氨基酸、核酸和必需脂肪酸的獨特組合可以產生協同效應,促進關節軟骨的修復並減少關節的進一步惡化。

How Does Perna Work to Improve Joint Function? 
The exact mechanism or mechanisms, by which Perna canaliculus works to control and perhaps reverse arthritis is not yet clearly understood. Research over the past 20 years has revealed that Perna contains a number of potentially active compounds that work against inflammation and the destructive cycle of degenerative joint disease. The unique combination of bioiogically active compounds, chelated minerals, glycosaminoglycans (chondroitin sulfates), amino acids, nucleic acids and essential fatty acids may yield a synergistic effect that promotes repair of the articular cartilage and reduces further deterioration of the joint.

臨床評估顯示,青邊貽貝中的成分可改善關節潤滑、減輕發炎和關節疼痛,並改善受損關節的活動度和活動範圍。作為一種營養補充劑,青邊貽貝提供了身體用於重建軟骨的一些關鍵成分,甚至可能會使酶的活性失效,減少導致關節炎的破壞性循環。青邊貽貝的提取物似乎直接作用於軟骨細胞(參與製造軟骨的細胞)修復受損軟骨並改善結締組織彈性。

克萊姆森大學最近在 John Lawson 博士的指導下發現,骨關節炎(退化性關節炎)和類風濕性關節炎的免疫反應變化可能是疾病進展的重要指標。 Lawson 發現青邊貽貝確實具有免疫調節特性,可實際調整關節炎中的發炎反應。最後,青邊貽貝對減少細胞凋亡是有幫助,這是一種消除異常細胞的機制,可促使關節減緩退化和降低發炎症狀。解釋青邊貽貝逆轉關節炎有益效果的潛在因素包括:
  • 提供必要的構建成份,以氨基酸、複合礦物質、醣胺聚醣(GAG)重建受損軟骨。
  • 發揮抗炎/鎮痛作用。 
  • 含有硫酸軟骨素,可抑制軟骨和結締組織的酶促分解。
  • 調節免疫反應,降低關節炎中的發炎反應。
  • 減少細胞凋亡,降低關節炎的破壞性循環以阻止退化。
  • 含有抗組胺因子和減少發炎的前列腺素抑製劑。
  • 提供極其有價值的Omega-3(ETA),它是環白酶和脂氧合酶途徑的有效抑製劑,抑制軟骨和結締組織的酶促分解。

Clinical evaluation reveals that the components in Perna mussel improve joint lubrication, reduce inflammation and joint pain and improve the mobility and range of motion of the affected joint. As a nutritional supplement, Perna provides some of the key building blocks that the body uses to rebuild cartilage and may even work to deactivate the cartilage-destorying enzymes that cause further deterioration. Perna appears to work directly on chondrocytes (cells that are involved in manufacturing cartilage) to repair damaged cartilage and improve connective tissue elasticity 

Recent work at Clemson University, conducted by John Lawson, PhD, has found that immune response changes in both osteoarthritis (degenerative joint disease) and rheumatoid arthritis may be important indicators in the progression of the disease. Lawson has discovered that Perna canaliculus does have immune modulating properties that may actually down- regulate the pro-inflammatory cascade in arthritis. Last of all, Perna may have an effect on reducing cell apoptosis, a mechanism that eliminates aberrant immune cells that may prompt joint degeneration and inflammation. This finding, correlated with a decrease in inflammation, suggests that there may be a decrease in the generation of pathological immune cells, which the host then attempts to eradicate by apoptosis.

Potential factors that may explain the beneficial effects of Perna canaliculus in reversing arthritis include the fact that it: .
Provides the necessary building blocks to rebuild damaged cartilage in the form of amino acids, chelated minerals, glucosamine and glycosaminoglycans (GAGs) 
Exerts an anti-inflammatory/ analgesic effect. .
Contains chondroitin sulfates that may inhibit enzymatic breakdown of the cartilage and connective tissue. 
Causes an immune response shift which helps down-regulate the inflammatory cytokines.
Causes reduction in apoptosis response that may indicate a decrease of wayward cells contributing to the destructive cycles of arthritis. 
Contains an anti-histamine factor and prostaglandin inhibitors that reduce inflammation.
Provides extremely valuable Omega- 3 eicosatetraenoic acids (ETAs), which are potent inhibitors of the cycloozygenase and lipoxygenase pathways in which leukotrienes and other inflammatory agents produced. 

註:青邊貽貝提取物

紐西蘭特有種青邊貽貝,提取出的成分中以 GAG 醣胺聚醣最為矚目,因為一般的葡萄糖胺(Glucosamine)經過食用後大約6~8週才能轉換成 GAG,成為關節可用的營養,但是青邊貽貝提取物穩定存在豐富的 GAG可直接被關節使用,當然青邊貽貝提取物中含有與人體相似的天然礦物質與其他成分也有助於關節炎的整體改善。

圖片來源 My Swiss Life

青邊貽貝在生長曲線的高峰期(大約18個月)收成,以急速冷凍乾燥的方式加工成細粉,這種方式不會破壞營養與活性,因此完整保存蛋白質、複合碳水化合物、脂質、天然礦物質、氨基酸和粘多醣(GAG醣胺聚醣),為身體尤其是關節提供營養。符合潔淨海域、保存完整營養的青邊貽貝提取物,就會有「ORIGINAL PERNA EXTRAKT」的驗證標章。
圖片來源 My Swiss Life

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