Journal of

Introduction: Delay in wound healing is one of several complications of type 1 diabetes. It has been reported that the use of various herbal extracts such as Morus nigra increase the  wound healing.  Since,there are no studies on investigation of the effects of Morus nigra on wound healing in diabetics so this study was conducted to determine wound healing effects of Morus nigra in diabetic rats.
Methods: In this experimental study, the fresh fruits were blended and pressed. Then, the extract was filtered and then was passed through the filter paper then it was dried in shade. Diabetes was induced by injection of single dose of streptozotocin (60 mg/kg). The circular wound (diameter 8 cm) was created on the back of each rat. The wounds were topically treated with 10 or 20 percent of concentration of the extract. Wounds in control group were treated with saline and normal group received no treatment.  Wound areas were monitored on days 1, 6 and 11; the repaired tissues were removed for histological evaluations.
Result: Daily and local applications of the extract displayed significant wound healing activity through the reducing wound area and acceleration of wound contraction. Histological findings showed that various indices of tissue repairment such as  integrated epithelial,  typical granulated and regular collagen layers were mor obvious in  the treated wounds.
Conclusion: Topical application of the Morus nigra extract can accelrate wound contraction and improve the histological indices inclue formation of epithelial and granulated layers and increase collagen density in the repaired tissue.

Introduction: Collagen bears many applications in pharmacy and medicine, health and cosmetic products as well as food industry. In recent years, much attention has been paid to separation of collagen from marine organisms arising from the fact that its use in the diet is not restricted and triggers no risk of contagious diseases as well as religious restrictions. Moreover, fish collagen is unique in terms of its extremely high solubility in dilute acid on a scale with mammalian and chicken collagen. The purpose of this study was to investigate the isolation and evaluation of collagen from fish skin (Thunnus tonggol) as a biological material for medical tissue engineering.
Methods: Acid-soluble collagen (ASC) was isolated from fish skin using acetic acid. The Thunnus tonggol skin collagen was extracted by acid and base methods and evaluated by PAGE-SDS, FTIR and UV spectrophotography and amino acid composition analysis.
Results: The results, predicated on SDS-PAGE and amino acid compositions, demonstrated that the fish skin collagen is of type I. Fourier transform infrared analysis also revealed helical compositions of both collagens. UV spectrophotometry in the Thunnus tonggol skin collagen indicated a maximum absorption of 235 nm. The amount of collagen extracted from the Thunnus tonggol skin turned out to be 17.3%. Through analysis of collagen amino acid extracted from the mentioned fish, glycine was predominant. The growth and proliferation of human fibroblast cells on the collagen extracted from the Thunnus tonggol skin was more than control.
Conclusion: The results revealed that the fish collagen is an accessible and advantageous material for medical usage and tissue engineering.