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Walnut (Juglans regia L., fam. Juglandaceae) fruit is found to be very rich in phenolic compounds and thus to show wide spectrum of biological activities like antioxidant, anti-inflammatory, or antitumour properties. Ethanol or methanol are preferentially used for preparation of walnut extracts for cosmetic applications. However, it is commonly known that alcohol causes dehydration and redness of the skin. The aim of this work was to prepare aqueous extract of undamaged walnut seeds rich in pellicles and to evaluate its antioxidant, anti-apoptotic, anti-inflammatory, and anti-aging properties in vitro. Conducted research clearly demonstrated that simple water extraction of undamaged kernels with pellicles allows to obtain rich in phenolic compounds (36-38 mg per g of lyophilisate) walnut extract, which protects fibroblasts and keratinocytes against oxidative stress induced by UVB dose of 35 mJ/cm2 (5-6-h exposure on a sunny day), protects keratinocytes against UVB-induced apoptotic death, limits the development of the inflammation in epidermis, and also possesses ability to inhibit collagenase and elastase. Thus, obtained aqueous walnut extract (at relatively low concentration of 5 µg/ml) is found to be a promising compound of sunscreen and anti-aging cosmetic formulations.
Significant protease activity has been detected in somatic extract of adults and microfilarial stage of Setaria cervi, using general protease substrates and collagen. The pH optima studies of the somatic extract of adult females showed two peaks at 7.0 and 5.0 for collagenase activity. Both forms were purified using sequential DEAE-sepharose and Sephadex G-100 column chromatography. The purified enzymes had the molecular masses of 175 and 20 kDa and pH optima at 7.0 and 5.0, respectively. The 175 kDa collagenase was more sensitive to metal chelators and serine protease inhibitors. However, 20 kDa collagenase was sensitive to cysteine protease inhibitors. The IgG antibodies from W. bancrofti infected human sera inhibited both enzymes. Further the purified collagenases were used to digest total human IgG at their respective pH and for different lengths of time. The 175 kDa protein was capable of cleaving human IgG. The digestion appeared to be restricted to a single cleavage point of H-chain within the hinge region of IgG molecule and produced fragments of similar molecular mass (27 kDa) indicating cleavage to Fab and Fc fragments. The degree of digestion was found to be proportional to the incubation time at 37°C. No further digestion of either fragments were observed. The L-chains were apparently resistant to collagenase digestion in all cases. Thus, the results suggest that S. cervi collagenase might be involved in the defense mechanisms of the parasite against the immune response of the host.
Podisus maculiventris (Say) is a generalist predator attacking many insect species from different orders. The bug injects saliva into its prey's body. The ingested hemolymph and liquefied internal tissues pass through the bug's alimentary tract. Collagenase working on peptide bonds of collagen and basement membrane proteins, leads to the disintegration of the prey's internal organs. As yet, there is an almost complete lack of knowledge on the collagenase activity in P. maculiventris. The collagenase activity of the salivary glands and midgut was optimum at pH 8.0 which was congruent with the optimal pH of the total proteolytic activity of the salivary glands. More collagenolytic activity was determined in the posterior lobe of the salivary glands and anterior midgut. Significant inhibition of collagenolytic activity by ethylenediaminetetraacetic acid (EDTA) revealed the enzyme is a metalloproteinase. The collagenase activity notably decreased when the bug went hungry. The salivary gland collagenase is a vital enzyme in extra-oral digestion and facilitates the action of other digestive enzymes. The midgut collagenase may be involved in the digestion of the ingested muscle fibers. The collagenase probably acts as an intoxicating agent in the saliva (venom) of P. maculiventris. Paralysing toxins are present in the salivary gland secretion.
The ability of various peptides cleaved by plasmin from human fibrinogen and fibronectin or fibrinogen- and fibronectin- related synthetic peptides to induce histamine release from mast cells and collagenase and elastase from PMN- leukocytes was examined. Low molecular weight fibrinogen degradation products showed dose dependent secretion of collagenase. These peptides (mol. wt. 1.4 kD) at the concentration of 10⁻⁵ M released about 47% of collagenase and 13% of elastase. Synthetic fib- rinopeptides A and В had a similar strong collagenase releasing potency and also released histamine from mast cells. Peptides from plasmin digestion of fibronectin containing cell attachment site with sequence Arg-Gly-Asp-Ser and also synthetic peptide reproducing this aminoacid sequence at the concentration of 1000 µg/ml released about 50% of collagenase and 55% of elastase from PMN-leukocytes. Moreover peptides containing cell attachment and gelatin binding site induced histamine release from mast cells. The association of fibrinogen and fibronectin degradation with activation of mast cells may motivate the treatment with antihistaminic drugs of all pathological conditions where the intensive protein degradation takes place.
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