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Biology subjects

Zayed, M.

Publications and source records attributed to Zayed, M..

2 recordsLinked to original sources

Sustained Oxygenation Accelerates Diabetic Wound Healing by Simultaneously Promoting Epithelialization and Angiogenesis, and Decreasing Tissue Inflammation

Non-healing diabetic wound is one of the most common complications for diabetic patients. Chronic hypoxia is among the prominent factors that delay the wound healing process. Therefore, sustained oxygenation to alleviate hypoxia is hypothesized to promote diabetic wound healing. Yet it cannot be achieved by current clinical approaches including hyperbaric oxygen therapy. Herein, we developed a sustained oxygenation system consisting of oxygen-release microspheres and a reactive oxygen species (ROS)-scavenging hydrogel. The hydrogel was used to capture the ROS that is elevated in the diabetic wounds, and that may be generated due to oxygen release. The sustainedly released oxygen augmented survival and migration of keratinocytes and dermal fibroblasts; promoted angiogenic growth factor expression, and angiogenesis in the diabetic wounds; and decreased M1 macrophage density. These effects led to a significant increase of wound closure rate. These findings reveal that sustained oxygenation alone without using drugs is capable of healing diabetic wounds.

bioengineering

The possible anti-inflammatory activity of macrolide antibiotics in some animal models

Recently, there has been increasing evidence on the use of macrolide antibiotics in treatment of chronic inflammatory diseases through mechanisms distinct from their antibacterial activity. The key desired effect lies somewhere between these two therapeutic potentials and has not been identified yet. The aim of the present study was to evaluate the anti-inflammatory activity of the macrolide antibiotic azithromycin in formaldehyde induced arthritis and carrageenan induced air pouch in albino rats in comparison to the anti-rheumatic drug meloxicam. Results of Formaldehyde induced arthritis revealed that pretreatment of animals with a single daily dose of either azithromycin (10, 20 and 40 mg/kg) or meloxicam (4 mg/kg) for 15 days produced a significant reduction in inflammation size. Histopathological study showed that Formaldehyde produced marked inflammatory cell infiltration, congestion of blood vessels and soft tissue edema which were attenuated by azithromycin in dose dependent manner. The radiological study revealed that azithromycin attenuates soft tissue edema, periarticular bone resorption, narrowing of joint spaces and joint deformities induced by formaldehyde. This effect was marked with 40mg/kg azithromycin pre-treatment. In carrageenan, induced air pouch, results demonstrate that group of animals pretreated with azithromycin (10, 20 and 40 mg/kg) or meloxicam (4 mg/kg) for 6 days significantly attenuated the mean increase in total leukocyte count in air pouch exudate. In conclusion, the present work showed that azithromycin has antiinflammatory activity in the models tested and suggests that it can exert therapeutics effects independent of its anti-bacterial activity. Also, the anti-inflammatory effect of azithromycin was potent and even comparable to that of meloxicam.

pharmacology and toxicology