Effect of Ocimum sanctum Linn. on normal and dexamethasone suppressed wound healing.

Ethanolic extract of leaves of O. sanctum was investigated for normal wound healing and dexamethasone depressed healing using incision, excision and dead space wound models in albino rats. The extract of O. sanctum significantly increased the wound breaking strength in incision wound model. The extract treated wounds were found to epithelialize faster and the rate of wound contraction was significantly increased as compared to control wounds. Significant increase in wet and dry granulation tissue weight, granulation tissue breaking strength and hydroxyproline content in dead space wound model was observed. The extract significantly decreased the antihealing activities of dexamethasone in all the wound models. The results indicated that the leaf extract promotes wound healing significantly and able to overcome the wound healing suppressing action of dexamethasone. Histological examination of granulation tissue to determine the pattern of lay-down for collagen confirmed the results.

Wound healing property of ethanolic extract of leaves of Hyptis suaveolens with supportive role of antioxidant enzymes.

Ethanolic extract of leaves of Hyptis suaveolens was evaluated for its wound healing activity in ether-anaesthetized Wistar rats at two different doses (400 and 800 mg/kg) using incision, excision, and dead space wound model. Significant increase in skin breaking strength, granuloma breaking strength, wound contraction, hydroxyproline content and dry granuloma weight and decrease in epithelization period was observed. A supportive study made on granuloma tissue to estimate the levels of catalase and superoxide dismutase recorded a significant increase in the level of these antioxidant enzymes. Granuloma tissue was subjected to histopathological examination to determine the pattern of lay-down for collagen using Van Gieson and Masson Trichrome stains. Enhanced wound healing activity may be due to free radical scavenging action of the plant and enhanced level of antioxidant enzymes in granuloma tissue. Better collagenation may be because of improved antioxidant studies.

Inhibition of lysyl oxidase by isoniazid and its effect on wound healing.

Isoniazid, an antitubercular drug, is known to be a potent inhibitor of monoamine oxidases. Effects of this drug, on lysyl oxidase (also a monoamine oxidase) and other wound healing parameters were studied in albino rats, in presence and absence of pyridoxal phosphate, using a dead space wound model. Tensile strength, collagen and glycosaminoglycan contents as well as lysyl oxidase activity were estimated in the granuloma tissue harvested from 10 day old dead space wounds. Isoniazid inhibited lysyl oxidase activity and a decrease in tensile strength as well as collagen content were observed. The effects were reversed on administration of a stoichiometric amount of pyridoxal phosphate. Hexosamine level was increased and hexuronic acid level decreased in the drug treated animals. Therefore, isoniazid may decrease the mechanical strength of collagen by inhibiting lysyl oxidase, by competiting for its obligatory cofactor pyridoxal phosphate, as well as by interfering in electrostatic interactions between collagen and the ground substance.