Subterranean Roots Lecture Notes PDF

 Definition: The root is the plant axis, which grows vertically downwards into the soil away from light.  Origin: The dried peeled or unpeeled root and rhizome of Glycyrrhiza glabra var. typica known as Spanish Liquorice or Glycyrrhiza glabra var. glandulifera known as Russian Liquorice or of...

 Definition: The root is the plant axis, which grows vertically downwards into the soil away from light.  Origin: The dried peeled or unpeeled root and rhizome of Glycyrrhiza glabra var. typica known as Spanish Liquorice or Glycyrrhiza glabra var. glandulifera known as Russian Liquorice or of other varieties of Glycyrrhiza glabra, Family Leguminosae (Fabaceae). G. sources: Spain, France, England, Italy, Germany and USA, Southern Russia and Iran. MACROSCOPICAL CHARACTERS: Externally, the unpeeled is dark-brown to reddish-brown Internally, bright-yellow Liquorice, has a faint characteristic odour and a very sweet taste???? MICROSCOPICAL CHARACTERS Powdered liquorice is light-yellow in colour in the peeled or brownish- yellow in the unpeeled. Microscopically, it is characterised by the following fragments: 1. Fibres with crystal sheath, the fibre has a lignified thick wall, narrow lumen and acute apex. 2. Fragments of xylem vessels. 3.Prismatic crystals of calcium oxalate, free or in cells. 4. Numerous starch granules, free or in parenchyma cells. 5.Cork may be present, consisting of polygonal thin-walled cells with brown contents.  Liquorice (Sweet Wood) Crystal sheath Starch granules some showing slit-like hilum  Microscopical characters of the powder: Cork cells in side view Xylem vessels showing bordered pits Cork cells in surface view  Crystal sheath Starch granules Xylem vessels showing bordered pits Cork cells in surface view ACTIVE CONSTITUENTS Triterpenoidal oleanane saponins: glycyrrhizin about 5-7% (saponin like glycoside). - It is the sodium and calcium salts of glycyrrhizinic (glycyrrhizic) acid which is 50 times as sweet as sugar. - Upon hydrolysis the glycoside loses its sweet taste and converted to the aglycone glycyrrhetic acid (glycyrrhetin) plus 2 molecules of glucuronic acid. Glycyrrhizinic acid Active constituents 2- Flavonoid glycosides: liquiritin, isoliquiritin, liquiritoside, rhamnoliquiritin and rhamnoisoliquiritin. 3- Coumarin derivatives: hermiarin and umbelliferone. 4- Free sugars about 5-15% (glucose and sucrose) and polysaccharides. 5- Bitter principle: glycyramarin (abundant in the outer tissue) and responsible for the bitterness of the unpeeled drug. 6- Asparagine (amino acid for nervous system), proteins, fat and starch 29%. TESTS FOR IDENTITY 1- Mix a little of powdered liquorice with 1-2 drops of sulphuric acid (66% v/v); an orange-red colour is produced. 2- Shake the aqueous decoction of liquorice, a persistent froth is produced. USES AND PHARMACOLOGICAL EFFECTS 1-Treatment of peptic and duodenal ulcers: Glycyrrhizin containing extract showed significant effect in the healing of ulcers. The deglycyrrhizinized fraction (DGL) showed a bit less effect. Glycyrrhizin alone didn’t exhibit any effect !. Conclusion: The antiulcer effect is very obvious on combination of glycyrrhizin with other compounds (synergistic effect). However, DGL is the most common form used for ulcers. MECHANISM OF ULCER TREATMENTXX 1- DGL stimulates normal defense mechanisms (mucosal lining of the digestive tract) slightly than reducing acidity (H2-antagonists( 2- DGL shown to be as effective as H-2 antagonists / antacids in healing ulcers with fewer or no significant side effects. 3- DGL strongly indicated for the prevention of gastric ulcers in patients taking ulcerogenic drugs (aspirin, corticosteroids( 4- dose for DGL is 380 mg chewable tablets between or 20 minutes before meals (2-4 times daily) USES AND PHARMACOLOGICAL EFFECTS 2-Mineralocorticoid like action: This effect is attributed to: A- The affinity of glycyrrhetic acid for kidney aldosterone receptors. B- Glycyrrhetic acid inhibits 5-b-reductase and 11-b - hydroxydehydrogenase leading to accumulation of cortisol and aldosterone and consequently prolongation of their action. Uses and Pharmacological Effects The aforementioned pseudoaldosteronism. Pseudoaldosteronism leads to Na+ retention (hypernatremia) and K + loss (hypokalemia) in addition to hypertension  Causes of hypertension by Liquorice: The prolongation of aldosterone action increases the sensitivity of blood capillaries to catecholamines leading to hypertension. Na+ retention leads to retention of water and an increase in blood volume resulting in severe hypertension.  Uses and Pharmacological Effects 3- Anti-inflammatory effect: This effect is attributed to glycyrrhizin, glycyrrhetic acid, chalcones and flavonoids (especially in case of gastritis) by inhibition of prostaglandins & thromboxanes (aspirin-like) 4- Anit-allergic affect of glycyrrizin: The mechanism of this effect is: A- Inhibition of histamine release from antigen stimulated cells. B- It intensifies the inhibitory action induced by dexamethasone.  Uses and Pharmacological Effects 5- Antiviral activity: Glycyrrhizin inactivates certain types of virus such as Herpes simplex (irreversibly). It’s action based on the interaction with sensitive virus proteins when these proteins are synthesized in host cells.  Uses and Pharmacological Effects 6- Effect on liver : (Hepatoprotective) Glycyrrhizin and its aglycone are able to prevent the development of cirrhosis that was indicated by prevention of liver lesions in rats intoxicated with CCl4. (glycyrrhizin, cysteine, glycine in normal saline), improved liver function in Hepatitis B, HIV “AIDS”  Uses and Pharmacological Effects 7- Immunostimulant effects: glycyrrhizin and glycyrrhetinic acid induce interferons interferons bind to cell surfaces, and stimulate synthesis of intracellular proteins that block viral DNA. interferons also activate macrophages, and increase natural killer cell activity. IV glycyrrhizin daily causes improvement of immune function  Uses and Pharmacological Effects 8- Other uses and effects: Topically used in certain skin diseases as allergic inflammation and dermatitis. Treatment of rheumatic arthritis and Addison’s disease (hypofunction of adrenal gland). Demulcent and expectorant. Eczema and Psoriasis: Topical glycyrrhetinic acid exerted an effect similar to hydrocortisone and may even be better.  Uses and Pharmacological Effects 8- Other uses and effects: Glycyrrhetic Acid Hydrogen Succinate (GAHS) as a disodium salt used for oral and orofacial herpes infection. The nasal absorption of insulin in 1% GAHS is highly enhanced !!.