Human Platelet-Rich Plasma- and Extracellular Matrix-Derived Peptides Promote Impaired Cutaneous Wound Healing In Vivo

Previous work in our laboratory has described several pro-angiogenic short peptides derived from endothelial extracellular matrices degraded by bacterial collagenase. Here we tested whether these peptides could stimulate wound healing in vivo. Our experiments demonstrated that a peptide created as combination of fragments of tenascin X and fibrillin 1 (comb1) applied into cranial dermal wounds created in mice treated with cyclophosphamide to impair wound healing, can improve the rate of wound closure. Furthermore, we identify and characterize a novel peptide (UN3) created and modified from two naturally-occurring peptides, which are present in human platelet-rich plasma. In vitro testing of UN3 demonstrates that it causes a 50% increase in endothelial proliferation, 250% increase in angiogenic response and a tripling of epithelial cell migration in response to injury. Results of in vivo experiments where comb1 and UN3 peptides were added together to cranial wounds in cyclophosphamide-treated mice leads to improvement of wound vascularization as shown by an increase of the number of blood vessels present in the wound beds. Application of the peptides markedly promotes cellular responses to injury and essentially restores wound healing dynamics to those of normal, acute wounds in the absence of cyclophosphamide impairment. Our current work is aimed at understanding the mechanisms underlying the stimulatory effects of these peptides as well as identification of the cellular receptors mediating these effects.National Institutes of Health (U.S.) (Grant EY15125)National Institutes of Health (U.S.) (Grant EY19533)Wound Care Partners, LL

Host suitability studies and reporting of resistance to root-knot nematode (Meloidogyne incognita)

Efficient and improved agripreneurship cannot be attained if measures are not put in place to curtail crop losses due to nematode damage. This research was conducted to look at the level of resistance and susceptibility of selected annual crops to guide agripreneurs on what crops to adopt for planting in meloidogyne infested soils and in crop rotation as a method of cultural control. Five crops namely were randomly selected from different crop families and soillorganic manure medium in a 3:1 ratio was used as the planting medium. Nematode inoculum containing about 1000 larvae of the root knot nematode Meloidogyne incognita in 30ml of nematode slurry was used to inoculate the test crops with the control left un-inoculated. Data were collected on plant height, fresh root weight, fresh top weight and number of galls/plant. The data were analyzed using genstat and the mean separation done using Fisher’s least significant difference. The results showed that maize was resistant to the inoculum and a good control crop in nematode infested soils while the other four test crops (water-melon, green beans, tomato and green amaranthus) showed varying degrees of susceptibilities from the effect of the inoculum on all the parameters measured. Maize being immune to the inoculum can be used in rotation programmes as a cultural control crop in M. incognita infested plots to reduce the pest’s population and boost the yield of the follow-up crop.Keywords: Infestation, Nematode inoculum, Meloidogyne incognita, Resistance and Susceptibility